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Decision tree as a tool for the management of coastal aquifers of limited saturated thickness

In this paper, a decision tree is presented, constructed on the basis of hydrogeological characteristics (water table depth, freshwater thickness, surface area required and distance between wells), to choose the optimal groundwater extraction method in the case of a coastal unconfined aquifer. A comparison is made of the groundwater extraction methods in a freshwater aquifer of limited thickness occurring in coastal dunes in the eastern region of the Province of Buenos Aires (Argentina). The negative effects brought about by the wrong use of the groundwater extraction methods are analysed, because, as a result of excessive extraction, such methods lead to the dramatic decrease of the freshwater reserves. The decision tree is a useful tool to assist decision-makers as it suggests the most suitable groundwater extraction method options (vertical wells or wellpoints), as well as identifying areas that are unsuitable for sustainable groundwater extraction.




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Fluorescent Hybridization of Mycobacterium leprae in Skin Samples Collected in Burkina Faso [Mycobacteriology and Aerobic Actinomycetes]

Leprosy is caused by Mycobacterium leprae, and it remains underdiagnosed in Burkina Faso. We investigated the use of fluorescent in situ hybridization (FISH) for detecting M. leprae in 27 skin samples (skin biopsy samples, slit skin samples, and skin lesion swabs) collected from 21 patients from Burkina Faso and three from Côte d’Ivoire who were suspected of having cutaneous leprosy. In all seven Ziehl-Neelsen-positive skin samples (four skin biopsy samples and three skin swabs collected from the same patient), FISH specifically identified M. leprae, including one FISH-positive skin biopsy sample that remained negative after testing with PCR targeting the rpoB gene and with the GenoType LepraeDR assay. Twenty other skin samples and three negative controls all remained negative for Ziehl-Neelsen staining, FISH, and rpoB PCR. These data indicate the usefulness of a microscopic examination of skin samples after FISH for first-line diagnosis of cutaneous leprosy. Accordingly, FISH represents a potentially useful point-of-care test for the diagnosis of cutaneous leprosy.




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High-Content Screening, a Reliable System for Coxiella burnetii Isolation from Clinical Samples [Bacteriology]

Q fever, caused by Coxiella burnetii, is a worldwide zoonotic disease that may cause severe forms in humans and requires a specific and prolonged antibiotic treatment. Although current serological and molecular detection tools allow a reliable diagnosis of the disease, culture of C. burnetii strains is mandatory to assess their susceptibility to antibiotics and sequence their genome in order to optimize patient management and epidemiological studies. However, cultivating this fastidious microorganism is difficult and restricted to reference centers, as it requires biosafety level 3 laboratories and relies on cell culture performed by experienced technicians. In addition, the culture yield is low, which results in a small number of isolates being available. In this work, we developed a novel high-content screening (HCS) isolation strategy based on optimized high-throughput cell culture and automated microscopic detection of infected cells with specifically designed algorithms targeting cytopathic effects. This method was more efficient than the shell vial assay, at the level of time dependency, when applied to both frozen specimens (7 isolates recovered by HCS only, sensitivity 91% versus 78% for shell vial) and fresh samples (1 additional isolate using HCS, sensitivity 7% versus 5% for shell vial), for which most strains were recovered more rapidly with the new technique. In addition, detecting positive cultures by an automated microscope reduced the need for expertise and saved 24% of technician working time. Application of HCS to antibiotic susceptibility testing of 12 strains demonstrated that it was as efficient as the standard procedure that combines shell vial culture and quantitative PCR.




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Pooling Pharyngeal, Anorectal, and Urogenital Samples for Screening Asymptomatic Men Who Have Sex with Men for Chlamydia trachomatis and Neisseria gonorrhoeae [Bacteriology]

Screening for Chlamydia trachomatis and Neisseria gonorrhoeae at the pharyngeal, urogenital, and anorectal sites is recommended for men who have sex with men (MSM). Combining the three individual-site samples into a single pooled sample could result in significant cost savings, provided there is no significant sensitivity reduction. The aim of this study was to examine the sensitivity of pooled samples for detecting chlamydia and gonorrhea in asymptomatic MSM using a nucleic acid amplification test. Asymptomatic MSM who tested positive for chlamydia or gonorrhoea were invited to participate. Paired samples were obtained from participants prior to administration of treatment. To form the pooled sample, the anorectal swab was agitated in the urine specimen transport tube and then discarded. The pharyngeal swab and 2 ml of urine sample were then added to the tube. The difference in sensitivity between testing of pooled samples and individual-site testing was calculated against an expanded gold standard, where an individual is considered positive if either pooled-sample or individual-site testing returns a positive result. All samples were tested using the Aptima Combo 2 assay. A total of 162 MSM were enrolled in the study. Sensitivities of pooled-sample testing were 86% (94/109; 95% confidence interval [CI], 79 to 92%]) for chlamydia and 91% (73/80; 95% CI, 83 to 96%) for gonorrhea. The sensitivity reduction was significant for chlamydia (P = 0.02) but not for gonorrhea (P = 0.34). Pooling caused 22 infections (15 chlamydia and 7 gonorrhoea) to be missed, and the majority were single-site infections (19/22). Pooling urogenital and extragenital samples from asymptomatic MSM reduced the sensitivity of detection by approximately 10% for chlamydia but not for gonorrhea.




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Recombinase Polymerase Amplification and Lateral Flow Assay for Ultrasensitive Detection of Low-Density Plasmodium falciparum Infection from Controlled Human Malaria Infection Studies and Naturally Acquired Infections [Parasitology]

Microscopy and rapid diagnostic tests (RDTs) are the main diagnostic tools for malaria but fail to detect low-density parasitemias that are important for maintaining malaria transmission. To complement existing diagnostic methods, an isothermal reverse transcription-recombinase polymerase amplification and lateral flow assay (RT-RPA) was developed. We compared the performance with that of ultrasensitive reverse transcription-quantitative PCR (uRT-qPCR) using nucleic acid extracts from blood samples (n = 114) obtained after standardized controlled human malaria infection (CHMI) with Plasmodium falciparum sporozoites. As a preliminary investigation, we also sampled asymptomatic individuals (n = 28) in an area of malaria endemicity (Lambaréné, Gabon) to validate RT-RPA and assess its performance with unprocessed blood samples (dbRT-RPA). In 114 samples analyzed from CHMI trials, the positive percent agreement to uRT-qPCR was 90% (95% confidence interval [CI], 80 to 96). The negative percent agreement was 100% (95% CI, 92 to 100). The lower limit of detection was 64 parasites/ml. In Gabon, RT-RPA was 100% accurate with asymptomatic volunteers (n = 28), while simplified dbRT-RPA showed 89% accuracy. In a subgroup analysis, RT-RPA detected 9/10 RT-qPCR-positive samples, while loop-mediated isothermal amplification (LAMP) detected 2/10. RT-RPA is a reliable diagnostic test for asymptomatic low-density infections. It is particularly useful in settings where uRT-qPCR is difficult to implement.




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A Fully Automated Multiplex Assay for Diagnosis of Lyme Disease with High Specificity and Improved Early Sensitivity [Immunoassays]

Lyme borreliosis is a tick-borne disease caused by the Borrelia burgdorferi sensu lato complex. Bio-Rad Laboratories has developed a fully automated multiplex bead-based assay for the detection of IgM and IgG antibodies to B. burgdorferi. The BioPlex 2200 Lyme Total assay exhibits an improved rate of seropositivity in patients with early Lyme infection. Asymptomatic subjects from endemic and nonendemic origins demonstrated a seroreactivity rate of approximately 4% that was similar to other commercial assays evaluated in this study. Coupled to this result was the observation that the Lyme Total assay retained a high first-tier specificity of 96% while demonstrating a relatively high sensitivity of 91% among a well-characterized CDC Premarketing Lyme serum panel. The Lyme Total assay also performs well under a modified two-tier algorithm (sensitivity, 84.4 to 88.9%; specificity, 98.4 to 99.5%). Furthermore, the new assay is able to readily detect early Lyme infection in patient samples from outside North America.




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Development of a Sensitive and Rapid Recombinase Polymerase Amplification Assay for Detection of Anaplasma phagocytophilum [Chlamydiology and Rickettsiology]

Human granulocytic anaplasmosis (HGA) is a tick-borne disease caused by the obligate intracellular Gram-negative bacterium Anaplasma phagocytophilum. The disease often presents with nonspecific symptoms with negative serology during the acute phase. Direct pathogen detection is the best approach for early confirmatory diagnosis. Over the years, PCR-based molecular detection methods have been developed, but optimal sensitivity is not achieved by conventional PCR while real-time PCR requires expensive and sophisticated instruments. To improve the sensitivity and also develop an assay that can be used in resource-limited areas, an isothermal DNA amplification assay based on recombinase polymerase amplification (RPA) was developed. To do this, we identified a 171-bp DNA sequence within multiple paralogous copies of msp2 within the genome of A. phagocytophilum. Our novel RPA assay targeting this sequence has an analytical limit of detection of one genome equivalent copy of A. phagocytophilum and can reliably detect 125 bacteria/ml in human blood. A high level of specificity was demonstrated by the absence of nonspecific amplification using genomic DNA from human or DNA from other closely-related pathogenic bacteria, such as Anaplasma platys, Ehrlichia chaffeensis, Orientia tsutsugamushi, and Rickettsia rickettsii, etc. When applied to patient DNA extracted from whole blood, this new RPA assay was able to detect 100% of previously diagnosed A. phagocytophilum cases. The sensitivity and rapidness of this assay represents a major improvement for early diagnosis of A. phagocytophilum in human patients and suggest a role for better surveillance in its reservoirs or vectors, especially in remote regions where resources are limited.




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Development of a Novel and Rapid Antibody-Based Diagnostic for Chronic Staphylococcus aureus Infections Based on Biofilm Antigens [Immunoassays]

Prosthetic joint infections are difficult to diagnose and treat due to biofilm formation by the causative pathogens. Pathogen identification relies on microbial culture that requires days to weeks, and in the case of chronic biofilm infections, lacks sensitivity. Diagnosis of infection is often delayed past the point of effective treatment such that only the removal of the implant is curative. Early diagnosis of an infection based on antibody detection might lead to less invasive, early interventions. Our study examined antibody-based assays against the Staphylococcus aureus biofilm-upregulated antigens SAOCOL0486 (a lipoprotein), glucosaminidase (a domain of SACOL1062), and SACOL0688 (the manganese transporter MntC) for detection of chronic S. aureus infection. We evaluated these antigens by enzyme-linked immunosorbent assay (ELISA) using sera from naive rabbits and rabbits with S. aureus-mediated osteomyelitis, and then we validated a proof of concept for the lateral flow assay (LFA). The SACOL0688 LFA demonstrated 100% specificity and 100% sensitivity. We demonstrated the clinical diagnostic utility of the SACOL0688 antigen using synovial fluid (SF) from humans with orthopedic implant infections. Elevated antibody levels to SACOL0688 in clinical SF specimens correlated with 91% sensitivity and 100% specificity for the diagnosis of S. aureus infection by ELISA. We found measuring antibodies levels to SACOL0688 in SF using ELISA or LFA provides a tool for the sensitive and specific diagnosis of S. aureus prosthetic joint infection. Development of the LFA diagnostic modality is a desirable, cost-effective option, potentially providing rapid readout in minutes for chronic biofilm infections.




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Direct Determination of Pyrazinamide (PZA) Susceptibility by Sputum Microscopic Observation Drug Susceptibility (MODS) Culture at Neutral pH: the MODS-PZA Assay [Mycobacteriology and Aerobic Actinomycetes]

Pyrazinamide (PZA) is considered the pivot drug in all tuberculosis treatment regimens due to its particular action on the persistent forms of Mycobacterium tuberculosis. However, no drug susceptibility test (DST) is considered sufficiently reliable for routine application. Although molecular tests are endorsed, their application is limited to known PZA resistance associated mutations. Microbiological DSTs for PZA have been restricted by technical limitations, especially the necessity for an acidic pH. Here, for the first time, MODS culture at neutral pH was evaluated using high PZA concentrations (400 and 800 μg/ml) to determine PZA susceptibility directly from sputum samples. Sputum samples were cultured with PZA for up to 21 days at 37°C. Plate reading was performed at two time points: R1 (mean, 10 days) and R2 (mean, 13 days) for each PZA concentration. A consensus reference test, composed of MGIT-PZA, pncA sequencing, and the classic Wayne test, was used. A total of 182 samples were evaluated. The sensitivity and specificity for 400 μg/ml ranged from 76.9 to 89.7 and from 93.0 to 97.9%, respectively, and for 800 μg/ml ranged from 71.8 to 82.1 and from 95.8 to 98.6%, respectively. Compared to MGIT-PZA, our test showed a similar turnaround time (medians of 10 and 12 days for PZA-sensitive and -resistant isolates, respectively). In conclusion, MODS-PZA is presented as a fast, simple, and low-cost DST that could complement the MODS assay to evaluate resistance to the principal first-line antituberculosis drugs. Further optimization of test conditions would be useful in order to increase its performance.




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Improved Molecular Diagnosis of COVID-19 by the Novel, Highly Sensitive and Specific COVID-19-RdRp/Hel Real-Time Reverse Transcription-PCR Assay Validated In Vitro and with Clinical Specimens [Virology]

On 31 December 2019, the World Health Organization was informed of a cluster of cases of pneumonia of unknown etiology in Wuhan, China. Subsequent investigations identified a novel coronavirus, now named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), from the affected patients. Highly sensitive and specific laboratory diagnostics are important for controlling the rapidly evolving SARS-CoV-2-associated coronavirus disease 2019 (COVID-19) epidemic. In this study, we developed and compared the performance of three novel real-time reverse transcription-PCR (RT-PCR) assays targeting the RNA-dependent RNA polymerase (RdRp)/helicase (Hel), spike (S), and nucleocapsid (N) genes of SARS-CoV-2 with that of the reported RdRp-P2 assay, which is used in >30 European laboratories. Among the three novel assays, the COVID-19-RdRp/Hel assay had the lowest limit of detection in vitro (1.8 50% tissue culture infective doses [TCID50]/ml with genomic RNA and 11.2 RNA copies/reaction with in vitro RNA transcripts). Among 273 specimens from 15 patients with laboratory-confirmed COVID-19 in Hong Kong, 77 (28.2%) were positive by both the COVID-19-RdRp/Hel and RdRp-P2 assays. The COVID-19-RdRp/Hel assay was positive for an additional 42 RdRp-P2-negative specimens (119/273 [43.6%] versus 77/273 [28.2%]; P < 0.001), including 29/120 (24.2%) respiratory tract specimens and 13/153 (8.5%) non-respiratory tract specimens. The mean viral load of these specimens was 3.21 x 104 RNA copies/ml (range, 2.21 x 102 to 4.71 x 105 RNA copies/ml). The COVID-19-RdRp/Hel assay did not cross-react with other human-pathogenic coronaviruses and respiratory pathogens in cell culture and clinical specimens, whereas the RdRp-P2 assay cross-reacted with SARS-CoV in cell culture. The highly sensitive and specific COVID-19-RdRp/Hel assay may help to improve the laboratory diagnosis of COVID-19.




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Rapid evolution of piRNA-mediated silencing of an invading transposable element was driven by abundant de novo mutations [RESEARCH]

The regulation of transposable element (TE) activity by small RNAs is a ubiquitous feature of germlines. However, despite the obvious benefits to the host in terms of ensuring the production of viable gametes and maintaining the integrity of the genomes they carry, it remains controversial whether TE regulation evolves adaptively. We examined the emergence and evolutionary dynamics of repressor alleles after P-elements invaded the Drosophila melanogaster genome in the mid-twentieth century. In many animals including Drosophila, repressor alleles are produced by transpositional insertions into piRNA clusters, genomic regions encoding the Piwi-interacting RNAs (piRNAs) that regulate TEs. We discovered that ~94% of recently collected isofemale lines in the Drosophila melanogaster Genetic Reference Panel (DGRP) contain at least one P-element insertion in a piRNA cluster, indicating that repressor alleles are produced by de novo insertion at an exceptional rate. Furthermore, in our sample of approximately 200 genomes, we uncovered no fewer than 80 unique P-element insertion alleles in at least 15 different piRNA clusters. Finally, we observe no footprint of positive selection on P-element insertions in piRNA clusters, suggesting that the rapid evolution of piRNA-mediated repression in D. melanogaster was driven primarily by mutation. Our results reveal for the first time how the unique genetic architecture of piRNA production, in which numerous piRNA clusters can encode regulatory small RNAs upon transpositional insertion, facilitates the nonadaptive rapid evolution of repression.




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Circular RNA hsa_circ_0014130 Inhibits Apoptosis in Non-Small Cell Lung Cancer by Sponging miR-136-5p and Upregulating BCL2

Previous studies indicated that circular RNAs (circRNA) played vital roles in the development of non–small cell lung cancer (NSCLC). Although hsa_circ_0014130 might be a potential NSCLC biomarker, its function in NSCLC remains unknown. Thus, this study aimed to investigate the role of hsa_circ_0014130 in the progression of NSCLC. The levels of hsa_circ_0014130 in NSCLC tissues and adjacent normal tissues were determined by qRT-PCR. In addition, the expressions of Bcl-2 and cleaved caspase-3 in A549 cells were detected with Western blot analysis. Meanwhile, the dual luciferase reporter system assay was used to determine the interaction of hsa_circ_0014130 and miR-136-5p or Bcl-2 and miR-136-5p in NSCLC, respectively. The level of hsa_circ_0014130 was significantly upregulated in NSCLC tissues. Downregulation of hsa_circ_0014130 markedly inhibited the proliferation and invasion of A549 cells via inducing apoptosis. In addition, downregulation of hsa_circ_0014130 inhibited the tumorigenesis of subcutaneous A549 xenograft in mice in vivo. Meanwhile, mechanistic analysis indicated that downregulation of hsa_circ_0014130 decreased the expression of miR-136-5p–targeted gene Bcl-2 via acting as a competitive "sponge" of miR-136-5p. In this study, we found that hsa_circ_0014130 was upregulated in NSCLC tissues. In addition, hsa_circ_0014130 functions as a tumor promoter in NSCLC to promote tumor growth through upregulating Bcl-2 partially via "sponging" miR-136-5p.

Implications:

In conclusion, hsa_circ_0014130 might function as a prognostic factor for patients with NSCLC and might be a therapeutic target for the treatment of NSCLC in future.




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Hepatic Transporter Alterations by Nuclear Receptor Agonist T0901317 in Sandwich-Cultured Human Hepatocytes: Proteomic Analysis and PBPK Modeling to Evaluate Drug-Drug Interaction Risk [Metabolism, Transport, and Pharmacogenomics]

In vitro approaches for predicting drug-drug interactions (DDIs) caused by alterations in transporter protein regulation are not well established. However, reports of transporter regulation via nuclear receptor (NR) modulation by drugs are increasing. This study examined alterations in transporter protein levels in sandwich-cultured human hepatocytes (SCHH; n = 3 donors) measured by liquid chromatography–tandem mass spectrometry–based proteomic analysis after treatment with N-[4-(1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)phenyl]-N-(2,2,2-trifluoroethyl)benzenesulfonamide (T0901317), the first described synthetic liver X receptor agonist. T0901317 treatment (10 μM, 48 hours) decreased the levels of organic cation transporter (OCT) 1 (0.22-, 0.43-, and 0.71-fold of control) and organic anion transporter (OAT) 2 (0.38-, 0.38-, and 0.53-fold of control) and increased multidrug resistance protein (MDR) 1 (1.37-, 1.48-, and 1.59-fold of control). The induction of NR downstream gene expression supports the hypothesis that T0901317 off-target effects on farnesoid X receptor and pregnane X receptor activation are responsible for the unexpected changes in OCT1, OAT2, and MDR1. Uptake of the OCT1 substrate metformin in SCHH was decreased by T0901317 treatment. Effects of decreased OCT1 levels on metformin were simulated using a physiologically-based pharmacokinetic (PBPK) model. Simulations showed a clear decrease in metformin hepatic exposure resulting in a decreased pharmacodynamic effect. This DDI would not be predicted by the modest changes in simulated metformin plasma concentrations. Altogether, the current study demonstrated that an approach combining SCHH, proteomic analysis, and PBPK modeling is useful for revealing tissue concentration–based DDIs caused by unexpected regulation of hepatic transporters by NR modulators.

SIGNIFICANCE STATEMENT

This study utilized an approach combining sandwich-cultured human hepatocytes, proteomic analysis, and physiologically based pharmacokinetic modeling to evaluate alterations in pharmacokinetics (PK) and pharmacodynamics (PD) caused by transporter regulation by nuclear receptor modulators. The importance of this approach from a mechanistic and clinically relevant perspective is that it can reveal drug-drug interactions (DDIs) caused by unexpected regulation of hepatic transporters and enable prediction of altered PK and PD changes, especially for tissue concentration–based DDIs.




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PIP3 depletion rescues myoblast fusion defects in human rhabdomyosarcoma cells [SHORT REPORT]

Yen-Ling Lian, Kuan-Wei Chen, Yu-Ting Chou, Ting-Ling Ke, Bi-Chang Chen, Yu-Chun Lin, and Linyi Chen

Myoblast fusion is required for myotube formation during myogenesis, and defects in myoblast differentiation and fusion have been implicated in a number of diseases, including human rhabdomyosarcoma. Although transcriptional regulation of the myogenic program has been studied extensively, the mechanisms controlling myoblast fusion remain largely unknown. This study identified and characterized the dynamics of a distinct class of blebs, termed bubbling blebs, which are smaller than those that participate in migration. The formation of these bubbling blebs occurred during differentiation and decreased alongside a decline in phosphatidylinositol-(3,4,5)-trisphosphate (PIP3) at the plasma membrane before myoblast fusion. In a human rhabdomyosarcoma-derived (RD) cell line that exhibits strong blebbing dynamics and myoblast fusion defects, PIP3 was constitutively abundant on the membrane during myogenesis. Targeting phosphatase and tensin homolog (PTEN) to the plasma membrane reduced PIP3 levels, inhibited bubbling blebs and rescued myoblast fusion defects in RD cells. These findings highlight the differential distribution and crucial role of PIP3 during myoblast fusion and reveal a novel mechanism underlying myogenesis defects in human rhabdomyosarcoma.




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Encoding, Consolidation, and Renormalization in Depression: Synaptic Homeostasis, Plasticity, and Sleep Integrate Rapid Antidepressant Effects [Review Articles]

Recent studies have strived to find an association between rapid antidepressant effects and a specific subset of pharmacological targets and molecular pathways. Here, we propose a broader hypothesis of encoding, consolidation, and renormalization in depression (ENCORE-D), which suggests that, fundamentally, rapid and sustained antidepressant effects rely on intrinsic homeostatic mechanisms evoked as a response to the acute pharmacological or physiologic effects triggered by the treatment. We review evidence that supports the notion that various treatments with a rapid onset of action, such as ketamine, electroconvulsive therapy, and sleep deprivation, share the ability to acutely excite cortical networks, which increases synaptic potentiation, alters patterns of functional connectivity, and ameliorates depressive symptoms. We proceed to examine how the initial effects are short-lived and, as such, require both consolidation during wake and maintenance throughout sleep to remain sustained. Here, we incorporate elements from the synaptic homeostasis hypothesis and theorize that the fundamental mechanisms of synaptic plasticity and sleep, particularly the homeostatic emergence of slow-wave electroencephalogram activity and the renormalization of synaptic strength, are at the center of sustained antidepressant effects. We conclude by discussing the various implications of the ENCORE-D hypothesis and offer several considerations for future experimental and clinical research.

Significance Statement

Proposed molecular perspectives of rapid antidepressant effects fail to appreciate the temporal distribution of the effects of ketamine on cortical excitation and plasticity as well as the prolonged influence on depressive symptoms. The encoding, consolidation, and renormalization in depression hypothesis proposes that the lasting clinical effects can be best explained by adaptive functional and structural alterations in neural circuitries set in motion in response to the acute pharmacological effects of ketamine (i.e., changes evoked during the engagement of receptor targets such as N-methyl-D-aspartate receptors) or other putative rapid-acting antidepressants. The present hypothesis opens a completely new avenue for conceptualizing and targeting brain mechanisms that are important for antidepressant effects wherein sleep and synaptic homeostasis are at the center stage.




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Proposal for Systemic-Therapy Response-Assessment Criteria at the Time of PSMA PET/CT Imaging: The PSMA PET Progression Criteria

In around 20% of men with prostate cancer, metastasis develops during the course of their disease. Accordingly, discovering and developing new potent treatment strategies for patients with metastatic prostate cancer has been a major research focus during the last few decades. Identifying disease progression, especially within clinical trials, is essential in determining drug effectiveness. One major remaining question is how best to define disease progression. The criteria of the Prostate Cancer Clinical Trials Working Group (PCWG2) include clinical and laboratory parameters, as well as conventional imaging modalities such as MRI, CT, and bone scan findings, but advanced molecular imaging techniques, especially prostate-specific membrane antigen (PSMA) PET findings, are not considered. This is a problem because PSMA PET is used not only for detecting biochemical recurrence but also for restaging and as an intermediate-endpoint biomarker in ongoing clinical trials. Therefore, response criteria and PSMA PET progression (PPP) criteria need to be established with some urgency. The intent of this article is therefore to define prostate cancer progression by PSMA PET criteria. Our PPP proposal is based on the same principles as were applied for the PCGW2 criteria but adds value by including PSMA PET criteria. PPP defines PSMA treatment response using 3 different criteria. The first is the appearance of 2 or more new PSMA-positive distant lesions. The second is the appearance of 1 new PSMA-positive lesion plus consistent clinical or laboratory data and recommended confirmation by biopsy or correlative imaging within 3 mo of PSMA PET. The third is an increase in size or PSMA uptake of 1 or more existing lesions by at least 30%, plus consistent clinical or laboratory data or confirmation by biopsy or correlative imaging within 3 mo of PSMA PET.




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A Conversation Between Ignasi Carrio and Ken Herrmann




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Efficacy and safety of two doses of budesonide/formoterol fumarate metered dose inhaler in COPD

Inhaled corticosteroid/long-acting β2-agonist combination therapy is a recommended treatment option for patients with chronic obstructive pulmonary disease (COPD) and increased exacerbation risk, particularly those with elevated blood eosinophil levels. SOPHOS (NCT02727660) evaluated the efficacy and safety of two doses of budesonide/formoterol fumarate dihydrate metered dose inhaler (BFF MDI) versus formoterol fumarate dihydrate (FF) MDI, each delivered using co-suspension delivery technology, in patients with moderate-to-very severe COPD and a history of exacerbations.

In this phase 3, randomised, double-blind, parallel-group, 12–52-week, variable length study, patients received twice-daily BFF MDI 320/10 µg or 160/10 µg, or FF MDI 10 µg. The primary endpoint was change from baseline in morning pre-dose trough forced expiratory volume in 1 s (FEV1) at week 12. Secondary and other endpoints included assessments of moderate/severe COPD exacerbations and safety.

The primary analysis (modified intent-to-treat) population included 1843 patients (BFF MDI 320/10 µg, n=619; BFF MDI 160/10 µg, n=617; and FF MDI, n=607). BFF MDI 320/10 µg and 160/10 µg improved morning pre-dose trough FEV1 at week 12 versus FF MDI (least squares mean differences 34 mL [p=0.0081] and 32 mL [p=0.0134], respectively), increased time to first exacerbation (hazard ratios 0.827 [p=0.0441] and 0.803 [p=0.0198], respectively) and reduced exacerbation rate (rate ratios 0.67 [p=0.0001] and 0.71 [p=0.0010], respectively). Lung function and exacerbation benefits were driven by patients with blood eosinophil counts ≥150 cells·mm–3. The incidence of adverse events was similar, and pneumonia rates were low (≤2.4%) across treatments.

SOPHOS demonstrated the efficacy and tolerability of BFF MDI 320/10 µg and 160/10 µg in patients with moderate-to-very severe COPD at increased risk of exacerbations.




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An Extensive Meta-Metagenomic Search Identifies SARS-CoV-2-Homologous Sequences in Pangolin Lung Viromes

ABSTRACT

In numerous instances, tracking the biological significance of a nucleic acid sequence can be augmented through the identification of environmental niches in which the sequence of interest is present. Many metagenomic data sets are now available, with deep sequencing of samples from diverse biological niches. While any individual metagenomic data set can be readily queried using web-based tools, meta-searches through all such data sets are less accessible. In this brief communication, we demonstrate such a meta-metagenomic approach, examining close matches to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in all high-throughput sequencing data sets in the NCBI Sequence Read Archive accessible with the "virome" keyword. In addition to the homology to bat coronaviruses observed in descriptions of the SARS-CoV-2 sequence (F. Wu, S. Zhao, B. Yu, Y. M. Chen, et al., Nature 579:265–269, 2020, https://doi.org/10.1038/s41586-020-2008-3; P. Zhou, X. L. Yang, X. G. Wang, B. Hu, et al., Nature 579:270–273, 2020, https://doi.org/10.1038/s41586-020-2012-7), we note a strong homology to numerous sequence reads in metavirome data sets generated from the lungs of deceased pangolins reported by Liu et al. (P. Liu, W. Chen, and J. P. Chen, Viruses 11:979, 2019, https://doi.org/10.3390/v11110979). While analysis of these reads indicates the presence of a similar viral sequence in pangolin lung, the similarity is not sufficient to either confirm or rule out a role for pangolins as an intermediate host in the recent emergence of SARS-CoV-2. In addition to the implications for SARS-CoV-2 emergence, this study illustrates the utility and limitations of meta-metagenomic search tools in effective and rapid characterization of potentially significant nucleic acid sequences.

IMPORTANCE Meta-metagenomic searches allow for high-speed, low-cost identification of potentially significant biological niches for sequences of interest.




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Exceptionally well-preserved Permocalculus cf. tenellus (Pia) (Gymnocodiaceae) from Upper Permian Khuff Formation limestones, Saudi Arabia

An exceptionally well-preserved specimen of the articulated rhodophyte Permocalculus, compared with P. tenellus sensu Elliott, 1955, is described from fine-grained Upper Permian limestones of the Khuff Formation of Saudi Arabia. Longitudinal medullary and sheaf-like cortical filaments extend through the uniserial series of elongate-globular, concave- and convex-terminating, interlocking segments for which they are interpreted to have functioned in articulation. The filaments tend to splay and branch laterally into the cortex where they terminate at the pores. At the terminal aperture, the filaments extend as bifurcating and possibly trifurcating branches and may serve as the origin of a new segment. Numerous elongate-globular chambers, up to five in each row and intimately involved with the filaments, are developed in the outer medulla and are considered to represent reproductive sporangia. The specimen is considered to have occupied predominantly low-energy, normal to slightly elevated salinity, shallow conditions within the subtidal regime of a lagoon.




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Two-Way Short Message Service (SMS) Communication May Increase Pre-Exposure Prophylaxis Continuation and Adherence Among Pregnant and Postpartum Women in Kenya

ABSTRACTIntroduction:We evaluated a 2-way short message service (SMS) communication platform to improve continuation of pre-exposure prophylaxis (PrEP) for HIV prevention among Kenyan women who initiated PrEP within routine maternal child health (MCH) and family planning clinics.Methods:We adapted an existing SMS platform (Mobile WACh [mWACh]) to send PrEP-tailored, theory-based SMS and allow clients to communicate with a remote nurse. Women who did not have HIV and who were initiating PrEP at 2 MCH/family planning clinics in Kisumu County, Kenya, from February to October 2018, were offered enrollment into the mWACh-PrEP program; SMS communication was free. We evaluated acceptability, satisfaction, and implementation metrics. In a pre/postevaluation, we compared PrEP continuation at 1-month postinitiation among women who initiated PrEP in the period before (n=166) versus after mWACh-PrEP implementation, adjusting for baseline differences.Results:Of the 334 women who were screened for enrollment into the mWACh-PrEP program; 193 (58%) were eligible and of those, 190 (98%) accepted enrollment. Reasons for ineligibility (n=141) included no phone access (29%) and shared SIM cards (25%). Median age was 25 years (interquartile range=22–30), and 91% were MCH clients. Compared to women who initiated PrEP in the month before mWACh-PrEP implementation, women who enrolled in mWACh-PrEP were more likely to return for their first PrEP follow-up visit (40% vs. 53%; adjusted risk ratio [aRR]=1.26; 95% confidence interval [CI]= 1.06, 1.50; P=.008) and more likely to continue PrEP (22% vs. 43%; aRR=1.75; 95% CI=1.21, 2.55; P=.003). Among those who returned, 99% reported successful receipt of SMS through the mWACh-PrEP system and 94% reported that mWACh-PrEP helped them understand PrEP better. Concerns about PrEP use, how it works, and side effects accounted for the majority (80%) of issues raised by participants using SMS.Conclusions:Two-way SMS expanded support for PrEP and opportunities for dialogue beyond the clinic and enabled women to ask and receive answers in real time regarding PrEP, which facilitated its continued use.




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National Surgical, Obstetric, and Anesthesia Plans Supporting the Vision of Universal Health Coverage




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Intrahepatic Fat and Postprandial Glycemia Increase After Consumption of a Diet Enriched in Saturated Fat Compared With Free Sugars

OBJECTIVE

Debate continues regarding the influence of dietary fats and sugars on the risk of developing metabolic diseases, including insulin resistance and nonalcoholic fatty liver disease (NAFLD). We investigated the effect of two eucaloric diets, one enriched with saturated fat (SFA) and the other enriched with free sugars (SUGAR), on intrahepatic triacylglycerol (IHTAG) content, hepatic de novo lipogenesis (DNL), and whole-body postprandial metabolism in overweight males.

RESEARCH DESIGN AND METHODS

Sixteen overweight males were randomized to consume the SFA or SUGAR diet for 4 weeks before consuming the alternate diet after a 7-week washout period. The metabolic effects of the respective diets on IHTAG content, hepatic DNL, and whole-body metabolism were investigated using imaging techniques and metabolic substrates labeled with stable-isotope tracers.

RESULTS

Consumption of the SFA diet significantly increased IHTAG by mean ± SEM 39.0 ± 10.0%, while after the SUGAR diet IHTAG was virtually unchanged. Consumption of the SFA diet induced an exaggerated postprandial glucose and insulin response to a standardized test meal compared with SUGAR. Although whole-body fat oxidation, lipolysis, and DNL were similar following the two diets, consumption of the SUGAR diet resulted in significant (P < 0.05) decreases in plasma total, HDL, and non-HDL cholesterol and fasting β-hydroxybutyrate plasma concentrations.

CONCLUSIONS

Consumption of an SFA diet had a potent effect, increasing IHTAG together with exaggerating postprandial glycemia. The SUGAR diet did not influence IHTAG and induced minor metabolic changes. Our findings indicate that a diet enriched in SFA is more harmful to metabolic health than a diet enriched in free sugars.




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Efficacy and Safety of Liraglutide 3.0 mg in Individuals With Overweight or Obesity and Type 2 Diabetes Treated With Basal Insulin: The SCALE Insulin Randomized Controlled Trial

OBJECTIVE

Most individuals with type 2 diabetes also have obesity, and treatment with some diabetes medications, including insulin, can cause further weight gain. No approved chronic weight management medications have been prospectively investigated in individuals with overweight or obesity and insulin-treated type 2 diabetes. The primary objective of this study was to assess the effect of liraglutide 3.0 mg versus placebo on weight loss in this population.

RESEARCH DESIGN AND METHODS

Satiety and Clinical Adiposity—Liraglutide Evidence (SCALE) Insulin was a 56-week, randomized, double-blind, placebo-controlled, multinational, multicenter trial in individuals with overweight or obesity and type 2 diabetes treated with basal insulin and ≤2 oral antidiabetic drugs.

RESULTS

Individuals were randomized to liraglutide 3.0 mg (n = 198) or placebo (n = 198), combined with intensive behavioral therapy (IBT). At 56 weeks, mean weight change was –5.8% for liraglutide 3.0 mg versus –1.5% with placebo (estimated treatment difference –4.3% [95% CI –5.5; –3.2]; P < 0.0001). With liraglutide 3.0 mg, 51.8% of individuals achieved ≥5% weight loss versus 24.0% with placebo (odds ratio 3.41 [95% CI 2.19; 5.31]; P < 0.0001). Liraglutide 3.0 mg was associated with significantly greater reductions in mean HbA1c and mean daytime glucose values and less need for insulin versus placebo, despite a treat-to-glycemic-target protocol. More hypoglycemic events were observed with placebo than liraglutide 3.0 mg. No new safety or tolerability issues were observed.

CONCLUSIONS

In individuals with overweight or obesity and insulin-treated type 2 diabetes, liraglutide 3.0 mg as an adjunct to IBT was superior to placebo regarding weight loss and improved glycemic control despite lower doses of basal insulin and without increases in hypoglycemic events.




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Global Disability Burdens of Diabetes-Related Lower-Extremity Complications in 1990 and 2016

OBJECTIVE

No study has reported global disability burden estimates for individual diabetes-related lower-extremity complications (DRLECs). The Global Burden of Disease (GBD) study presents a robust opportunity to address this gap.

RESEARCH DESIGN AND METHODS

GBD 2016 data, including prevalence and years lived with disability (YLDs), for the DRLECs of diabetic neuropathy, foot ulcer, and amputation with and without prosthesis were used. The GBD estimated prevalence using data from systematic reviews and DisMod-MR 2.1, a Bayesian meta-regression tool. YLDs were estimated as the product of prevalence estimates and disability weights for each DRLEC. We reported global and sex-, age-, region-, and country-specific estimates for each DRLEC for 1990 and 2016.

RESULTS

In 2016, an estimated 131 million people (1.8% of the global population) had DRLECs. An estimated 16.8 million YLDs (2.1% global YLDs) were caused by DRLECs, including 12.9 million (95% uncertainty interval 8.30–18.8) from neuropathy only, 2.5 million (1.7–3.6) from foot ulcers, 1.1 million (0.7–1.4) from amputation without prosthesis, and 0.4 million (0.3–0.5) from amputation with prosthesis. Age-standardized YLD rates of all DRLECs increased by between 14.6% and 31.0% from 1990 estimates. Male-to-female YLD ratios ranged from 0.96 for neuropathy only to 1.93 for foot ulcers. The 50- to 69-year-old age-group accounted for 47.8% of all YLDs from DRLECs.

CONCLUSIONS

These first-ever global estimates suggest that DRLECs are a large and growing contributor to the disability burden worldwide and disproportionately affect males and middle- to older-aged populations. These findings should facilitate policy makers worldwide to target strategies at populations disproportionately affected by DRLECs.




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Meningioma 1 is indispensable for mixed lineage leukemia-rearranged acute myeloid leukemia

Mixed lineage leukemia (MLL/KMT2A) rearrangements (MLL-r) are one of the most frequent chromosomal aberrations in acute myeloid leukemia. We evaluated the function of Meningioma 1 (MN1), a co-factor of HOXA9 and MEIS1, in human and murine MLL-rearranged leukemia by CRISPR-Cas9 mediated deletion of MN1. MN1 was required for in vivo leukemogenicity of MLL positive murine and human leukemia cells. Loss of MN1 inhibited cell cycle and proliferation, promoted apoptosis and induced differentiation of MLL-rearranged cells. Expression analysis and chromatin immunoprecipitation with sequencing from previously reported data sets demonstrated that MN1 primarily maintains active transcription of HOXA9 and HOXA10, which are critical downstream genes of MLL, and their target genes like BCL2, MCL1 and Survivin. Treatment of MLL-rearranged primary leukemia cells with anti-MN1 siRNA significantly reduced their clonogenic potential in contrast to normal CD34+ hematopoietic progenitor cells, suggesting a therapeutic window for MN1 targeting. In summary, our findings demonstrate that MN1 plays an essential role in MLL fusion leukemias and serve as a therapeutic target in MLL-rearranged acute myeloid leukemia.




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"Take Me To Your Leader": An Electrophysiological Appraisal of the Role of Hub Cells in Pancreatic Islets

The coordinated electrical activity of β-cells within the pancreatic islet drives oscillatory insulin secretion. A recent hypothesis postulates that specially equipped "hub" or "leader" cells within the β-cell network drive islet oscillations and that electrically silencing or optically ablating these cells suppresses coordinated electrical activity (and thus insulin secretion) in the rest of the islet. In this Perspective, we discuss this hypothesis in relation to established principles of electrophysiological theory. We conclude that whereas electrical coupling between β-cells is sufficient for the propagation of excitation across the islet, there is no obvious electrophysiological mechanism that explains how hyperpolarizing a hub cell results in widespread inhibition of islet electrical activity and disruption of their coordination. Thus, intraislet diffusible factors should perhaps be considered as an alternate mechanism.




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Starvation causes female-to-male sex reversal through lipid metabolism in the teleost fish, medaka (Olyzias latipes) [RESEARCH ARTICLE]

Yuta Sakae, Akira Oikawa, Yuki Sugiura, Masatoshi Mita, Shuhei Nakamura, Toshiya Nishimura, Makoto Suematsu, and Minoru Tanaka

The teleost fish, medaka (Oryzias latipes), employs the XX/XY genetic sex determination system. We show here that the phenotypic sex of medaka is affected by changes in lipid metabolism. Medaka larvae subjected to 5 days of starvation underwent female-to-male sex reversal. Metabolomic and RT-qPCR analyses indicated that pantothenate metabolism was suppressed by starvation. Consistently, inhibiting the pantothenate metabolic pathway caused sex reversal. The final metabolite in this pathway is coenzyme A, an essential factor for lipogenesis. Inhibiting fatty acid synthesis, the first step of lipogenesis, also caused sex reversal. The expression of dmrt1, a critical gene for male development, was suppressed by starvation, and a dmrt1 (13) mutant did not show sex reversal under starvation. Collectively, these results indicate that fatty acid synthesis is involved in female-to-male sex reversal through ectopic expression of male gene dmrt1 under starvation.




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Guidance for psychological therapists: information for GPs advising patients on antidepressant withdrawal




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Efficacy and Safety of Use of the Fasting Algorithm for Singaporeans With Type 2 Diabetes (FAST) During Ramadan: A Prospective, Multicenter, Randomized Controlled Trial [Original Research]

PURPOSE

We aimed to evaluate the efficacy and safety of use of the Fasting Algorithm for Singaporeans with Type 2 Diabetes (FAST) during Ramadan.

METHODS

We performed a prospective, multicenter, randomized controlled trial. The inclusion criteria were age ≥21 years, baseline glycated hemoglobin (HbA1c) level ≤9.5%, and intention to fast for ≥10 days during Ramadan. Exclusion criteria included baseline estimated glomerular filtration rate <30 mL/min, diabetes-related hospitalization, and short-term corticosteroid therapy. Participants were randomized to intervention (use of FAST) or control (usual care without FAST) groups. Efficacy outcomes were HbA1c level and fasting blood glucose and postprandial glucose changes, and the safety outcome was incidence of major or minor hypoglycemia during the Ramadan period. Glycemic variability and diabetes distress were also investigated. Linear mixed models were constructed to assess changes.

RESULTS

A total of 97 participants were randomized (intervention: n = 46, control: n = 51). The HbA1c improvement during Ramadan was 4 times greater in the intervention group (–0.4%) than in the control group (–0.1%) (P = .049). The mean fasting blood glucose level decreased in the intervention group (–3.6 mg/dL) and increased in the control group (+20.9 mg/dL) (P = .034). The mean postprandial glucose level showed greater improvement in the intervention group (–16.4 mg/dL) compared to the control group (–2.3 mg/dL). There were more minor hypoglycemic events based on self-monitered blood glucose readings in the control group (intervention: 4, control: 6; P = .744). Glycemic variability was not significantly different between the 2 groups (P = .284). No between-group differences in diabetes distress were observed (P = .479).

CONCLUSIONS

Our findings emphasize the importance of efficacious, safe, and culturally tailored epistemic tools for diabetes management.




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Anticoagulants Safety and Effectiveness in General Practice: A Nationwide Prospective Cohort Study [Original Research]

PURPOSE

Most real-world studies on anticoagulants have been based on health insurance databases or performed in secondary care. The aim of this study was to compare safety and effectiveness between patients treated with vitamin K antagonists (VKAs) and patients treated with direct oral anticoagulants (DOACs) in a general practice setting.

METHODS

The CACAO study (Comparison of Accidents and their Circumstances with Oral Anticoagulants) is a multicenter prospective cohort study conducted among ambulatory patients taking an oral anticoagulant. Participants were patients from the study’s cross-sectional phase receiving oral anticoagulants because of nonvalvular atrial fibrillation, for secondary prevention of venous thromboembolism, or both. They were followed as usual for 1 year by their general practitioners, who collected data on changes in therapy, thromboembolic events, bleeding, and deaths. All events were adjudicated by an independent committee. We used a propensity score and a Cox regression model to derive hazard ratios.

RESULTS

Between April and December 2014, a total of 3,082 patients were included. At 1 year, 42 patients (1.7%) had experienced an arterial or venous event; 151 (6.1%) had experienced bleeding, including 47 (1.9%) who experienced major bleeding; and 105 (4.1%) had died. There was no significant difference between the VKA and DOAC groups regarding arterial or venous events, or major bleeding. The VKA group had a lower risk of overall bleeding (hazard ratio = 0.65; 95% CI, 0.43-0.98) but twice the risk of death (hazard ratio = 1.98; 95% CI, 1.15-3.42).

CONCLUSIONS

VKAs and DOACs had fairly similar safety and effectiveness in general practice. The substantially higher incidence of deaths with VKAs is consistent with known data from health insurance databases and calls for further research to understand its cause.




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Predicting Opioid Use Following Discharge After Cesarean Delivery [Original Research]

PURPOSE

Although cesarean delivery is the most common surgical procedure in the United States, postoperative opioid prescribing varies greatly. We hypothesized that patient characteristics, procedural characteristics, or both would be associated with high vs low opioid use after discharge. This information could help individualize prescriptions.

METHODS

In this prospective cohort study, we quantified opioid use for 4 weeks following hospital discharge after cesarean delivery. Predischarge characteristics were obtained from health records, and patients self-reported total opioid use postdischarge on weekly questionnaires. Opioid use was quantified in milligram morphine equivalents (MMEs). Binomial and Poisson regression analyses were performed to assess predictors of opioid use after discharge.

RESULTS

Of the 233 patients starting the study, 203 (87.1%) completed at least 1 questionnaire and were included in analyses (86.3% completed all 4 questionnaires). A total of 113 patients were high users (>75 MMEs) and 90 patients were low users (≤75 MMEs) of opioids postdischarge. The group reporting low opioid use received on average 44% fewer opioids in the 24 hours before discharge compared with the group reporting high opioid use (mean = 33.0 vs 59.3 MMEs, P <.001). Only a minority of patients (11.4% to 15.8%) stored leftover opioids in a locked location, and just 31 patients disposed of leftover opioids.

CONCLUSIONS

Knowledge of predischarge opioid use can be useful as a tool to inform individualized opioid prescriptions, help optimize nonopioid analgesia, and reduce opioid use. Additional studies are needed to evaluate the impact of implementing such measures on prescribing practices, pain, and functional outcomes.




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On the Frontline of the COVID-19 Outbreak: Keeping Patients on Long-Term Dialysis Safe




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A Sampling of Highlights from the Literature: Article Recommendations from Our Deputy and Senior Editors




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Multifunctional Acidocin 4356 Combats Pseudomonas aeruginosa through Membrane Perturbation and Virulence Attenuation: Experimental Results Confirm Molecular Dynamics Simulation [Biotechnology]

A longstanding awareness in generating resistance to common antimicrobial therapies by Gram-negative bacteria has made them a major threat to global health. The application of antimicrobial peptides as a therapeutic agent would be a great opportunity to combat bacterial diseases. Here, we introduce a new antimicrobial peptide (~8.3 kDa) from probiotic strain Lactobacillus acidophilus ATCC 4356, designated acidocin 4356 (ACD). This multifunctional peptide exerts its anti-infective ability against Pseudomonas aeruginosa through an inhibitory action on virulence factors, bacterial killing, and biofilm degradation. Reliable performance over tough physiological conditions and low hemolytic activity confirmed a new hope for the therapeutic setting. Antibacterial kinetic studies using flow cytometry technique showed that the ACD activity is related to the change in permeability of the membrane. The results obtained from molecular dynamic (MD) simulation were perfectly suited to the experimental data of ACD behavior. The structure-function relationship of this natural compound, along with the results of transmission electron microscopy analysis and MD simulation, confirmed the ability of the ACD aimed at enhancing bacterial membrane perturbation. The peptide was effective in the treatment of P. aeruginosa infection in mouse model. The results support the therapeutic potential of ACD for the treatment of Pseudomonas infections.

IMPORTANCE Multidrug-resistant bacteria are a major threat to global health, and the Pseudomonas bacterium with the ability to form biofilms is considered one of the main causative agents of nosocomial infections. Traditional antibiotics have failed because of increased resistance. Thus, finding new biocompatible antibacterial drugs is essential. Antimicrobial peptides are produced by various organisms as a natural defense mechanism against pathogens, inspiring the possible design of the next generation of antibiotics. In this study, a new antimicrobial peptide was isolated from Lactobacillus acidophilus ATCC 4356, counteracting both biofilm and planktonic cells of Pseudomonas aeruginosa. A detailed investigation was then conducted concerning the functional mechanism of this peptide by using fluorescence techniques, electron microscopy, and in silico methods. The antibacterial and antibiofilm properties of this peptide may be important in the treatment of Pseudomonas infections.




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The N-Acetylglucosaminidase LytB of Streptococcus pneumoniae Is Involved in the Structure and Formation of Biofilms [Genetics and Molecular Biology]

The N-acetylglucosaminidase LytB of Streptococcus pneumoniae is involved in nasopharyngeal colonization and is responsible for cell separation at the end of cell division; thus, lytB mutants form long chains of cells. This paper reports the construction and properties of a defective pneumococcal mutant producing an inactive LytB protein (LytBE585A). It is shown that an enzymatically active LytB is required for in vitro biofilm formation, as lytB mutants (either lytB or producing the inactive LytBE585A) are incapable of forming substantial biofilms, despite that extracellular DNA is present in the biofilm matrix. Adding small amounts (0.5 to 2.0 μg/ml) of exogenous LytB or some LytB constructs restored the biofilm-forming capacity of lytB mutants to wild-type levels. The LytBE585A mutant formed biofilm more rapidly than lytB mutants in the presence of LytB. This suggests that the mutant protein acted in a structural role, likely through the formation of complexes with extracellular DNA. The chain-dispersing capacity of LytB allowed the separation of daughter cells, presumably facilitating the formation of microcolonies and, finally, of biofilms. A role for the possible involvement of LytB in the synthesis of the extracellular polysaccharide component of the biofilm matrix is also discussed.

IMPORTANCE It has been previously accepted that biofilm formation in S. pneumoniae must be a multigenic trait because the mutation of a single gene has led to only to partial inhibition of biofilm production. In the present study, however, evidence that the N-acetylglucosaminidase LytB is crucial in biofilm formation is provided. Despite the presence of extracellular DNA, strains either deficient in LytB or producing a defective LytB enzyme formed only shallow biofilms.




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Unexpected Abundance and Diversity of Phototrophs in Mats from Morphologically Variable Microbialites in Great Salt Lake, Utah [Microbial Ecology]

Microbial mat communities are associated with extensive (~700 km2) and morphologically variable carbonate structures, termed microbialites, in the hypersaline Great Salt Lake (GSL), Utah. However, whether the composition of GSL mat communities covaries with microbialite morphology and lake environment is unknown. Moreover, the potential adaptations that allow the establishment of these extensive mat communities at high salinity (14% to 17% total salts) are poorly understood. To address these questions, microbial mats were sampled from seven locations in the south arm of GSL representing different lake environments and microbialite morphologies. Despite the morphological differences, microbialite-associated mats were taxonomically similar and were dominated by the cyanobacterium Euhalothece and several heterotrophic bacteria. Metagenomic sequencing of a representative mat revealed Euhalothece and subdominant Thiohalocapsa populations that harbor the Calvin cycle and nitrogenase, suggesting they supply fixed carbon and nitrogen to heterotrophic bacteria. Fifteen of the next sixteen most abundant taxa are inferred to be aerobic heterotrophs and, surprisingly, harbor reaction center, rhodopsin, and/or bacteriochlorophyll biosynthesis proteins, suggesting aerobic photoheterotrophic (APH) capabilities. Importantly, proteins involved in APH are enriched in the GSL community relative to that in microbialite mat communities from lower salinity environments. These findings indicate that the ability to integrate light into energy metabolism is a key adaptation allowing for robust mat development in the hypersaline GSL.

IMPORTANCE The earliest evidence of life on Earth is from organosedimentary structures, termed microbialites, preserved in 3.481-billion-year-old (Ga) rocks. Phototrophic microbial mats form in association with an ~700-km2 expanse of morphologically diverse microbialites in the hypersaline Great Salt Lake (GSL), Utah. Here, we show taxonomically similar microbial mat communities are associated with morphologically diverse microbialites across the lake. Metagenomic sequencing reveals an abundance and diversity of autotrophic and heterotrophic taxa capable of harvesting light energy to drive metabolism. The unexpected abundance of and diversity in the mechanisms of harvesting light energy observed in GSL mat populations likely function to minimize niche overlap among coinhabiting taxa, provide a mechanism(s) to increase energy yield and osmotic balance during salt stress, and enhance fitness. Together, these physiological benefits promote the formation of robust mats that, in turn, influence the formation of morphologically diverse microbialite structures that can be imprinted in the rock record.




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Inactivation of Pseudomonas aeruginosa Biofilms by 405-Nanometer-Light-Emitting Diode Illumination [Physiology]

Biofilm formation by Pseudomonas aeruginosa contributes to its survival on surfaces and represents a major clinical threat because of the increased tolerance of biofilms to disinfecting agents. This study aimed to investigate the efficacy of 405-nm light-emitting diode (LED) illumination in eliminating P. aeruginosa biofilms formed on stainless steel coupons under different temperatures. Time-dependent killing assays using planktonic and biofilm cells were used to determine the antimicrobial and antibiofilm activities of LED illumination. We also evaluated the effects of LED illumination on the disinfectant susceptibility, biofilm structure, extracellular polymeric substance (EPS) structure and composition, and biofilm-related gene expression of P. aeruginosa biofilm cells. Results showed that the abundance of planktonic P. aeruginosa cells was reduced by 0.88, 0.53, and 0.85 log CFU/ml following LED treatment for 2 h compared with untreated controls at 4, 10, and 25°C, respectively. For cells in biofilms, significant reductions (1.73, 1.59, and 1.68 log CFU/cm2) were observed following LED illumination for 2 h at 4, 10, and 25°C, respectively. Moreover, illuminated P. aeruginosa biofilm cells were more sensitive to benzalkonium chloride or chlorhexidine than untreated cells. Scanning electron microscopy and confocal laser scanning microscopic observation indicated that both the biofilm structure and EPS structure were disrupted by LED illumination. Further, reverse transcription-quantitative PCR revealed that LED illumination downregulated the transcription of several genes associated with biofilm formation. These findings suggest that LED illumination has the potential to be developed as an alternative method for prevention and control of P. aeruginosa biofilm contamination.

IMPORTANCE Pseudomonas aeruginosa can form biofilms on medical implants, industrial equipment, and domestic surfaces, contributing to high morbidity and mortality rates. This study examined the antibiofilm activity of 405-nm light-emitting diode (LED) illumination against mature biofilms formed on stainless steel coupons. We found that the disinfectant susceptibility, biofilm structure, and extracellular polymeric substance structure and composition were disrupted by LED illumination. We then investigated the transcription of several critical P. aeruginosa biofilm-related genes and analyzed the effect of illumination temperature on the above characteristics. Our results confirmed that LED illumination could be developed into an effective and safe method to counter P. aeruginosa biofilm contamination. Further research will be focused on the efficacy and application of LED illumination for elimination of complicated biofilms in the environment.




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Unnecessary antibiotic prescribing in a Canadian primary care setting: a descriptive analysis using routinely collected electronic medical record data

Background:

Unnecessary antibiotic use in the community in Canada is not well defined. Our objective was to quantify unnecessary antibiotic prescribing in a Canadian primary care setting.

Methods:

We performed a descriptive analysis in Ontario from April 2011 to March 2016 using the Electronic Medical Records Primary Care database linked to other health administrative data sets at ICES. We determined antibiotic prescribing rates (per 100 patient–physician encounters) for 23 common conditions and estimated rates of unnecessary prescribing using predefined expected prescribing rates, both stratified by condition and patient age group.

Results:

The study included 341 physicians, 204 313 patients and 499 570 encounters. The rate of unnecessary antibiotic prescribing for included conditions was 15.4% overall and was 17.6% for those less than 2 years of age, 18.6% for those aged 2–18, 14.5% for those aged 19–64 and 13.0% for those aged 65 or more. The highest unnecessary prescribing rates were observed for acute bronchitis (52.6%), acute sinusitis (48.4%) and acute otitis media (39.3%). The common cold, acute bronchitis, acute sinusitis and miscellaneous nonbacterial infections were responsible for 80% of the unnecessary antibiotic prescriptions. Of all antibiotics prescribed, 12.0% were for conditions for which they are never indicated, and 12.3% for conditions for which they are rarely indicated. In children, 25% of antibiotics were for conditions for which they are never indicated (e.g., common cold).

Interpretation:

Antibiotics were prescribed unnecessarily for 15.4% of included encounters in a Canadian primary care setting. Almost one-quarter of antibiotics were prescribed for conditions for which they are rarely or never indicated. These findings should guide safe reductions in the use of antibiotics for the common cold, bronchitis and sinusitis.




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The SARS-CoV-2 Outbreak: Diagnosis, Infection Prevention, and Public Perception

At the end of 2019 and early 2020, an outbreak of pneumonia of unknown etiology emerged in the city of Wuhan in China. The cases were found to be caused by a novel beta coronavirus, which was subsequently named SARS-CoV-2 by the World Health Organization (WHO). The virus has since spread further in China and to other regions of the world, having infected more than 88 K people, and causing close to 3000 deaths as of March 1, 2020. More than 50 million people remain in quarantine at this time. Scientists and clinicians globally are working swiftly to combat COVID-19, the respiratory disease caused by the virus. Notably, diagnostic assays have been developed rapidly in many countries, and have played significant roles in diagnosis, monitoring, surveillance, and infection control. Starting February 29, 2020, the development and performance of molecular testing for SARS-CoV-2 in high complexity Clinical Laboratory Improvement Amendments (CLIA) laboratories prior to emergency use authorization was allowed by the US FDA. Although the epidemic is evolving rapidly, many valuable lessons have been learned and many questions remain to be answered. Here we invited multiple experts across the globe from clinical laboratories, public health laboratories, infection control, and diagnostic industry to share their views on the diagnosis, infection control, and public perception of SARS-CoV-2.




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Salivary AMY1 Copy Number Variation Modifies Age-Related Type 2 Diabetes Risk

Abstract
Background
Copy number variation (CNV) in the salivary amylase gene (AMY1) modulates salivary α-amylase levels and is associated with postprandial glycemic traits. Whether AMY1-CNV plays a role in age-mediated change in insulin resistance (IR) is uncertain.
Methods
We measured AMY1-CNV using duplex quantitative real-time polymerase chain reaction in two studies, the Boston Puerto Rican Health Study (BPRHS, n = 749) and the Genetics of Lipid-Lowering Drug and Diet Network study (GOLDN, n = 980), and plasma metabolomic profiles in the BPRHS. We examined the interaction between AMY1-CNV and age by assessing the relationship between age with glycemic traits and type 2 diabetes (T2D) according to high or low copy numbers of the AMY1 gene. Furthermore, we investigated associations between metabolites and interacting effects of AMY1-CNV and age on T2D risk.
Results
We found positive associations of IR with age among subjects with low AMY1-copy-numbers in both studies. T2D was marginally correlated with age in participants with low AMY1-copy-numbers but not with high AMY1-copy-numbers in the BPRHS. Metabolic pathway enrichment analysis identified the pentose metabolic pathway based on metabolites that were associated with both IR and the interactions between AMY1-CNV and age. Moreover, in older participants, high AMY1-copy-numbers tended to be associated with lower levels of ribonic acid, erythronic acid, and arabinonic acid, all of which were positively associated with IR.
Conclusions
We found evidence supporting a role of AMY1-CNV in modifying the relationship between age and IR. Individuals with low AMY1-copy-numbers tend to have increased IR with advancing age.




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A Yellow-Green Cerebrospinal Fluid Sample

body fluidsCSF




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Sailing through the Three Gorges in China

At about 6300 km, Chang Jiang or Long River (长江) is the longest river in Asia and third longest in the world. It is the longest in the world to flow entirely within one country and plays a large role in the history, culture, and economy of China. For thousands of years, the river has been used for water, irrigation, sanitation, transportation, industry, boundary-marking, and war. Passing through 10 provinces, it commences its flow from the Tanggula Mountains (唐古拉山) in ethnic Tibetan Qinghai (青海) Province in northwest China and ends at the East China Sea in Shanghai (上海). Along the middle reaches of the river, between the western upstream Baidi City (白帝城) of Chongqing (重庆) Municipality and Yichang (宜昌) city of Hubei (湖北) Province downstream, the river passes through 3 adjacent gorges, known as the Three Gorges (三峡): Qutang, Wuxia, and Xiling gorge (瞿塘, 巫峡, 西陵峡) cutting through the Wu Mountains (巫山). Spanning a distance of about 120 km, these gorges are noted for their natural beauty: unusual-looking mountain peaks ranging from 800 m to 2000 m, precipitous valleys, dense forest, and spectacular landscape. Many ancient government officials, scholars, poets, and painters visited the Three Gorges and left their impressions and praises in writings. Archeological discoveries in recent years have shown for the first time that the Three Gorges area should be recognized as the birthplace of Chinese civilization.




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"ERS International Congress 2019: highlights from Best Abstract awardees". Lorna E. Latimer, Marieke Duiverman, Mahmoud I. Abdel-Aziz, Gulser Caliskan, Sara M. Mensink-Bout, Alberto Mendoza-Valderrey, Aurelien Justet, Junichi Omura, Karthi Srika




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Additional safety consideration for azithromycin in the management of SARS-CoV-2 infection [Letters]




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Efficacy and Safety of Pembrolizumab in Previously Treated Advanced Neuroendocrine Tumors: Results From the Phase II KEYNOTE-158 Study

Purpose:

KEYNOTE-158 (ClinicalTrials.gov identifier: NCT02628067) investigated the efficacy and safety of pembrolizumab across multiple cancers. We present results from patients with previously treated advanced well-differentiated neuroendocrine tumors (NET).

Patients and Methods:

Pembrolizumab 200 mg was administered every 3 weeks for 2 years or until progression, intolerable toxicity, or physician/patient decision. Tumor imaging was performed every 9 weeks for the first year and then every 12 weeks. Endpoints included objective response rate (ORR) per RECIST v1.1 by independent central radiologic review (primary) and duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety (secondary).

Results:

A total of 107 patients with NETs of the lung, appendix, small intestine, colon, rectum, or pancreas were treated. Median age was 59.0 years (range, 29–80), 44.9% had ECOG performance status 1, 40.2% had received ≥3 prior therapies for advanced disease, and 15.9% had PD-L1–positive tumors (combined positive score ≥1). Median follow-up was 24.2 months (range, 0.6–33.4). ORR was 3.7% (95% CI, 1.0–9.3), with zero complete responses and four partial responses (three pancreatic and one rectal) all in patients with PD-L1–negative tumors. Median DOR was not reached, with one of four responses ongoing after ≥21 months follow-up. Median PFS was 4.1 months (95% CI, 3.5–5.4); the 6-month PFS rate was 39.3%. Median OS was 24.2 months (95% CI, 15.8–32.5). Treatment-related adverse events (AE) occurred in 75.7% of patients, 21.5% of whom had grade 3–5 AEs.

Conclusions:

Pembrolizumab monotherapy showed limited antitumor activity and manageable safety in patients with previously treated advanced well-differentiated NETs.




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Efficacy and Safety of Duvelisib Following Disease Progression on Ofatumumab in Patients with Relapsed/Refractory CLL or SLL in the DUO Crossover Extension Study

Purpose:

In the phase III DUO trial, duvelisib, an oral dual PI3K-, inhibitor, demonstrated significantly improved efficacy versus ofatumumab [median (m) progression-free survival (PFS), 13.3 vs. 9.9 months (HR, 0.52; P < 0.0001); overall response rate [ORR], 74% vs. 45% (P < 0.0001)], with a manageable safety profile in patients with relapsed/refractory (R/R) chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL). We report results from patients with progressive disease (PD) after ofatumumab who crossed over to duvelisib in the DUO trial.

Patients and Methods:

Patients with radiographically confirmed PD after ofatumumab received duvelisib 25 mg twice daily in 28-day cycles until PD, intolerance, death, or study withdrawal. The primary endpoint was ORR per investigator. Secondary endpoints included duration of response (DOR), PFS, and safety.

Results:

As of December 14, 2018, 90 ofatumumab-treated patients in the DUO trial prior to crossover had an ORR of 29%, mDOR of 10.4 months, and mPFS of 9.4 months. After crossover, 77% of patients (69/90) achieved a response, with an mDOR of 14.9 months and mPFS of 15.7 months. Patients with del(17p) and/or TP53 mutations had similar outcomes [ORR, 77% (20/26); mPFS, 14.7 months]. Notably, 73% of patients (47/64) with disease previously refractory to ofatumumab achieved a response. The most frequent any-grade/grade 3/4 treatment-emergent adverse events were diarrhea (47%/23%), neutropenia (26%/23%), pyrexia (24%/4%), cutaneous reactions (23%/4%), and thrombocytopenia (10%/6%).

Conclusions:

Duvelisib demonstrated high response rates with good durability and a manageable safety profile in patients with R/R CLL/SLL who progressed on ofatumumab, including patients with high-risk disease and disease previously refractory to ofatumumab.




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Importation of Extensively Drug-Resistant Salmonella enterica Serovar Typhi Cases in Ontario, Canada [Susceptibility]

A strain of extensively drug-resistant (XDR) Salmonella enterica serovar Typhi has caused a large ongoing outbreak in Pakistan since 2016. In Ontario, Canada, 10 cases of mainly bloodstream infections (n = 9) were identified in patients who traveled to Pakistan. Whole-genome sequencing showed that Canadian cases were genetically related to the Pakistan outbreak strain. The appearance of XDR typhoid cases in Ontario prompted a provincial wide alert to physicians to recommend treatment with carbapenems or azithromycin in suspected typhoid cases with travel history to Pakistan.




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Using Genetic Distance from Archived Samples for the Prediction of Antibiotic Resistance in Escherichia coli [Epidemiology and Surveillance]

The rising rates of antibiotic resistance increasingly compromise empirical treatment. Knowing the antibiotic susceptibility of a pathogen’s close genetic relative(s) may improve empirical antibiotic selection. Using genomic and phenotypic data for Escherichia coli isolates from three separate clinically derived databases, we evaluated multiple genomic methods and statistical models for predicting antibiotic susceptibility, focusing on potentially rapidly available information, such as lineage or genetic distance from archived isolates. We applied these methods to derive and validate the prediction of antibiotic susceptibility to common antibiotics. We evaluated 968 separate episodes of suspected and confirmed infection with Escherichia coli from three geographically and temporally separated databases in Ontario, Canada, from 2010 to 2018. Across all approaches, model performance (area under the curve [AUC]) ranges for predicting antibiotic susceptibility were the greatest for ciprofloxacin (AUC, 0.76 to 0.97) and the lowest for trimethoprim-sulfamethoxazole (AUC, 0.51 to 0.80). When a model predicted that an isolate was susceptible, the resulting (posttest) probabilities of susceptibility were sufficient to warrant empirical therapy for most antibiotics (mean, 92%). An approach combining multiple models could permit the use of narrower-spectrum oral agents in 2 out of every 3 patients while maintaining high treatment adequacy (~90%). Methods based on genetic relatedness to archived samples of E. coli could be used to predict antibiotic resistance and improve antibiotic selection.




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Safety and Pharmacokinetic Characterization of Nacubactam, a Novel {beta}-Lactamase Inhibitor, Alone and in Combination with Meropenem, in Healthy Volunteers [Clinical Therapeutics]

Nacubactam is a novel β-lactamase inhibitor with dual mechanisms of action as an inhibitor of serine β-lactamases (classes A and C and some class D) and an inhibitor of penicillin binding protein 2 in Enterobacteriaceae. The safety, tolerability, and pharmacokinetics of intravenous nacubactam were evaluated in single- and multiple-ascending-dose, placebo-controlled studies. Healthy participants received single ascending doses of nacubactam of 50 to 8,000 mg, multiple ascending doses of nacubactam of 1,000 to 4,000 mg every 8 h (q8h) for up to 7 days, or nacubactam of 2,000 mg plus meropenem of 2,000 mg q8h for 6 days after a 3-day lead-in period. Nacubactam was generally well tolerated, with the most frequently reported adverse events (AEs) being mild to moderate complications associated with intravenous access and headache. There was no apparent relationship between drug dose and the pattern, incidence, or severity of AEs. No clinically relevant dose-related trends were observed in laboratory safety test results. No serious AEs, dose-limiting AEs, or deaths were reported. After single or multiple doses, nacubactam pharmacokinetics appeared linear, and exposure increased in an approximately dose-proportional manner across the dose range investigated. Nacubactam was excreted largely unchanged into urine. Coadministration of nacubactam with meropenem did not significantly alter the pharmacokinetics of either drug. These findings support the continued clinical development of nacubactam and demonstrate the suitability of meropenem as a potential β-lactam partner for nacubactam. (The studies described in this paper have been registered at ClinicalTrials.gov under NCT02134834 [single ascending dose study] and NCT02972255 [multiple ascending dose study].)