ai

Fin24.com | Erdogan says Khashoggi murder was planned, rejecting Saudi claim

Turkish President Recep Tayyip Erdogan rejected Riyadh’s account of the killing of dissident journalist Jamal Khashoggi at Saudi Arabia’s consulate in Istanbul, saying the murder was the result of a meticulously planned plot and calling on the Saudi king to hold all culprits to account.




ai

Fin24.com | Saudi Crown Prince has `blood on his hands', Erdogan aide says

Saudi Crown Prince Mohammed bin Salman has “blood on his hands” in the killing of journalist Jamal Khashoggi, a top aide to Turkey’s president said, in his country’s first direct accusation against the power behind the Saudi throne.




ai

Fin24.com | Pakistan's 'penniless billionaires' expose money laundering frenzy

It took rickshaw driver Mohammad Rasheed a year to save 300 rupees to buy his daughter a bike, so when he found three billion rupees ($22.5 million) had passed through an unused bank account in his name, he was stunned ... and scared.




ai

Fin24.com | Trump, Xi set for `big meeting' as investors await trade truce

President Donald Trump and China’s Xi Jinping will sit down for a highly anticipated dinner with investors and allies eager for a truce in the trade war between the world’s two largest economies.




ai

Fin24.com | Dowdy sectors prevail

There's something distinctly un-sexy about the BFA Index by sector.




ai

Fin24.com | OPINION | Air travel shutdowns herald peak oil demand

The future choices made by airlines matter a great deal for the oil market, say Liam Denning and Brooke Sutherland.




ai

A Framework for Responsible Aid to Burundi




ai

Maintaining Momentum in the Congo: The Ituri Problem




ai

The Congo's Transition Is Failing: Crisis in the Kivus




ai

Africa Needs Aid for Security not Just Poverty




ai

Maintain the UN Mission in the Democratic Republic Of Congo




ai

Difficile transition vers la démocratie et la paix au Congo




ai

Espoir de paix durable au Burundi, si les derniers rebelles hutus y sont intégrés




ai

Congo: Four Priorities for Sustainable Peace in Ituri




ai

Burundi: Arusha Spirit Must Prevail




ai

UN Must Stop Backing Congo's Disastrous Operation Against Marauding Rebel Militias




ai

After MONUC, Should MONUSCO Continue to Support Congolese Military Campaigns?

For more than a year and a half, UN peacekeepers have continuously supported military operations conducted by the Congolese armed forces (FARDC) against the Rwandan rebels of the Democratic Forces for the Liberation of Rwanda (FDLR) in North and South Kivu.




ai

Derrière le problème des minerais des conflits, la gouvernance du Congo

A la veille de l’entrée en vigueur le 15 avril de l’obligation de rendre publique l’origine des minerais pour les grandes compagnies basées aux Etats-Unis, ICG a effectué une mission au Nord Kivu afin d’évaluer les différentes stratégies de lutte contre les minerais des conflits et leur impact sur le terrain.




ai

Afrique centrale : la corruption - l'obstacle majeur à la consolidation de la paix

La rechute est le risque majeur des pays post-conflit et l'une des principales raisons de cette rechute s'appelle la corruption.




ai

Eastern Congo: Why Stabilisation Failed

The Kivus region of eastern Congo again faces escalating violence, including by a rebel force acting as a proxy of neighbouring Rwanda. To stop the repetitive cycle of rebellion and avoid large-scale killing, donors and African mediators need to move from crisis management to conflict resolution with the right set of pressures on Kigali and Kinshasa.




ai

Understanding Conflict in Eastern Congo (I): The Ruzizi Plain

The Framework Agreement signed by the UN, African organisations and eleven countries and the deployment of an intervention brigade in North Kivu are positive steps, but conflicts in the Kivu region of the Democratic Republic of the Congo also require a bottom-up approach aimed at improving intercommunal relations and restoring peace at the local level.




ai

Semaine critique pour Bangui

Depuis jeudi et l’attaque de Bangui par les groupes anti-balaka qui viennent de province et sont composés de villageois et d’anciens militaires constitués en milices d’autodéfense, un calme précaire est revenu dans la capitale centrafricaine grâce au déploiement des militaires français.




ai

Danger de rechute au Burundi : question foncière et consolidation de la paix

Le Burundi est l’un des pays les plus pauvres (le taux de pauvreté atteint 67 %) et les plus petits d’Afrique (27 834 kilomètres carrés) avec l’une des plus grandes densités humaines du continent (près de 400 habitants par kilomètre carré). C’est du reste un pays profondément rural où seulement 11 % de la population réside en ville. Alors que l’accès à la terre et à la propriété est un véritable enjeu socio-économique, le Burundi fait face à de sérieux problèmes agricoles.




ai

Afrique Centrale: Pour une mission efficace en République centrafricaine

Incapable d’agir quand Crisis Group et d’autres organisations envoyaient des signaux d’alerte et qualifiaient la Centrafrique d’Etat fantôme, la communauté internationale doit dorénavant s’impliquer massivement, à des coûts largement supérieurs, suite aux pertes humaines considérables et aux déplacements massifs de population, et avec des chances de succès beaucoup plus faibles.




ai

Burundi: Godefroid Niyombaré avait mis en garde Nkurunziza

Alors qu’une tentative de coup d’Etat contre Pierre Nkurunziza, émanant de l’ex-chef d’état-major, Godefroid Niyombaré, est en cours au Burundi, Thierry Vircoulon chercheur à l'International Crisis Group, explique qui est le général putschiste et analyse, plus généralement, l'appareil sécuritaire du Burundi.




ai

Some Waiver States Can Seek Pause on School Ratings

States looking to renew NCLB waivers while they transition to new assessments ask to freeze school ratings in place for one year, the Education Department says.




ai

Ed. Dept., Virginia Stumble Over Waiver

Flawed achievement-gap targets in the state's NCLB flexibility waiver force a do-over and highlight complexities.




ai

Panel Finds Few Learning Gains From Testing Movement

A 10-year study by a blue-ribbon panel of scientists concludes that high-stakes testing and other accountability measures have largely failed to translate to real improvements in student achievement.




ai

An engineered double lipid II binding motifs-containing lantibiotic displays potent and selective antimicrobial activity against E. faecium [Chemistry; Biosynthesis]

Lipid II is an essential precursor of the bacterial cell wall biosynthesis and thereby an important target for various antibiotics. Several lanthionine-containing peptide antibiotics target lipid II with lanthionine-stabilized lipid II-binding motifs. Here, we used the biosynthesis system of the lantibiotic nisin to synthesize a two lipid II binding motifs-containing lantibiotic, termed TL19, which contains the N-terminal lipid II binding motif of nisin and the distinct C-terminal lipid II binding motif of one peptide of the two-component haloduracin (i.e. HalA1). Further characterization demonstrated that (i) TL19 exerts 64-fold stronger antimicrobial activity against E. faecium than nisin (1-22), which has only one lipid II binding site, and (ii) both the N- and C-terminal domains are essential for the potent antimicrobial activity of TL19, as evidenced by mutagenesis of each single and double domains. These results show the feasibility of a new approach to synthesize potent lantibiotics with two different lipid II binding motifs to treat specific antibiotic-resistant pathogens.




ai

Evaluation of the efficacy of antibiotic combinations against multidrug-resistant Pseudomonas aeruginosa in automated time-lapse microscopy and static time-kill experiments [Clinical Therapeutics]

Objectives: Antibiotic combination therapy is used for severe infections caused by multidrug-resistant (MDR) Gram-negative bacteria. Yet, data of which combinations are most effective is lacking. This study aimed to evaluate the in vitro efficacy of polymyxin B in combination with 13 other antibiotics against four clinical strains of MDR Pseudomonas aeruginosa.

Methods: We evaluated the interactions of polymyxin B in combination with amikacin, aztreonam, cefepime, chloramphenicol, ciprofloxacin, fosfomycin, meropenem, minocycline, rifampicin, temocillin, thiamphenicol or trimethoprim by automated time-lapse microscopy using predefined cut-off values indicating inhibition of growth (≤106 CFU/mL) at 24 h. Promising combinations were subsequently evaluated in static time-kill experiments.

Results: All strains were intermediate or resistant to polymyxin B, anti-pseudomonal β-lactams, ciprofloxacin and amikacin. Genes encoding β-lactamases (e.g., blaPAO and blaOXA-50) and mutations associated with permeability and efflux were detected in all strains. In the time-lapse microscopy experiments, positive interactions were found with 39 of 52 antibiotic combination/bacterial strain setups. Enhanced activity was found against all four strains with polymyxin B used in combination with aztreonam, cefepime, fosfomycin, minocycline, thiamphenicol and trimethoprim. Time kill experiments showed additive or synergistic activity with 27 of the 39 tested polymyxin B combinations, most frequently with aztreonam, cefepime, and meropenem.

Conclusion: Positive interactions were frequently found with the tested combinations, also against strains that harboured several resistance mechanisms to the single drugs and with antibiotics that are normally not active against P. aeruginosa. Further study is needed to explore the clinical utility of these combinations.




ai

Ceftobiprole Activity against Bacteria from Skin and Skin Structure Infections in the United States from 2016 through 2018 [Susceptibility]

Ceftobiprole medocaril is an advanced-generation cephalosporin prodrug that has qualified infectious disease product status granted by the US-FDA and is currently being evaluated in phase 3 clinical trials in patients with acute bacterial skin and skin structure infections (ABSSSIs) and in patients with Staphylococcus aureus bacteremia. In this study, the activity of ceftobiprole and comparators was evaluated against more than 7,300 clinical isolates collected in the United States from 2016 through 2018 from patients with skin and skin structure infections. The major species/pathogen groups were S. aureus (53%), Enterobacterales (23%), Pseudomonas aeruginosa (7%), β-hemolytic streptococci (6%), Enterococcus spp. (4%), and coagulase-negative staphylococci (2%). Ceftobiprole was highly active against S. aureus (MIC50/90, 0.5/1 mg/L; 99.7% susceptible by EUCAST criteria; 42% methicillin-resistant S. aureus [lsqb]MRSA[rsqb]). Ceftobiprole also exhibited potent activity against other Gram-positive cocci. The overall susceptibility of Enterobacterales to ceftobiprole was 84.8% (>99.0% susceptible for isolate subsets that exhibited a non-extended-spectrum β-lactamase [lsqb]ESBL[rsqb]-phenotype). A total of 74.4% of P. aeruginosa, 100% of β-hemolytic streptococci and coagulase-negative staphylococci, and 99.6% of Enterococcus faecalis isolates were inhibited by ceftobiprole at ≤4 mg/L. As expected, ceftobiprole was largely inactive against Enterobacterales that contained ESBL genes and Enterococcus faecium. Overall, ceftobiprole was highly active against most clinical isolates from the major Gram-positive and Gram-negative skin and skin structure pathogen groups collected at U.S. medical centers participating in the SENTRY Antimicrobial Surveillance Program during 2016–2018. The broad-spectrum activity of ceftobiprole, including potent activity against MRSA, supports its further evaluation for the potential ABSSSI indication.




ai

A Comparison of Clinical Outcomes among Intensive Care Unit Patients Receiving Ceftriaxone 1 gram daily or 2 grams daily [Clinical Therapeutics]

Background: Intensive care unit (ICU) patients may experience ceftriaxone underexposure but clinical outcomes data are lacking. The objective of this study was to determine the impact of ceftriaxone dosing on clinical outcomes amongst ICU patients without central nervous system (CNS) infection.

Methods: A retrospective study of ICU patients receiving intravenous, empiric ceftriaxone for non-CNS infections was conducted. Patients ≥18 years of age who received ≤2 grams of ceftriaxone daily for ≥72 hours were included and categorized as receiving ceftriaxone 1 gram or 2 grams daily. The primary, composite outcome was treatment failure: inpatient mortality and/or antibiotic escalation due to clinical worsening. Propensity score matching was performed based on the probability of receiving ceftriaxone 2 grams daily. Multivariable logistic regression determined the association between ceftriaxone dose and treatment failure in a propensity-matched cohort.

Results: A total of 212 patients were included in the propensity-matched cohort. The most common diagnoses (83.0%) were pneumonia and urinary tract infection. Treatment failure occurred in 17.0% and 5.7% of patients receiving 1 gram and 2 grams daily, respectively (p=0.0156). Overall inpatient mortality was 8.5%. Ceftriaxone 2 gram dosing was associated with a reduced likelihood of treatment failure (adjusted odds ratio=0.190; 95% confidence interval: 0.059 – 0.607). Other independent predictors of treatment failure included sequential organ failure assessment score (aOR 1.440, 95% CI 1.254 – 1.653) and creatinine clearance at 72 hours from ceftriaxone initiation (aOR 0.980, 95% CI (0.971 – 0.999).

Conclusions: Ceftriaxone 2 grams daily when used as appropriate antimicrobial coverage may be appropriate for ICU patients with lower mortality risk.




ai

Updated approaches against SARS-CoV-2 [Minireviews]

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lies behind the ongoing outbreak of coronavirus disease 2019 (COVID-19). There is a growing understanding of SARS-CoV-2 in the virology, epidemiology and clinical management strategies. However, no anti-SARS-CoV-2 drug or vaccine has been officially approved due to the absence of adequate evidence. Scientists are racing towards the development of treatment for COVID-19. Recent studies have revealed many attractive threptic options, even if some of them remain to be further confirmed in rigorous preclinical models and clinical trials. In this minireview, we aim to summarize the updated potential approaches against SARS-CoV-2. We emphasize that further efforts are warranted to develop the safest and most effective approach.




ai

Mutations in ArgS arginine-tRNA synthetase confer additional antibiotic-tolerance protection to ESBL-producing Burkholderia thailandensis [Mechanisms of Resistance]

Highly conserved PenI-type class A β-lactamase in pathogenic members of Burkholderia can evolve to extended-spectrum β-lactamase (ESBL), which exhibits hydrolytic activity towards third-generation cephalosporins, while losing its activity towards the original penicillin substrates. We describe three single-amino-acid-substitution mutations in the ArgS arginine-tRNA synthetase that confer extra antibiotic tolerance protection to ESBL-producing Burkholderia thailandensis. This pathway can be exploited to evade antibiotic tolerance induction in developing therapeutic measures against Burkholderia species, targeting their essential aminoacyl-tRNA synthetases.




ai

Spectrum of Beta-Lactamase Inhibition by the Cyclic Boronate QPX7728, an Ultra-Broad-Spectrum Beta-lactamase Inhibitor of Serine and Metallo Beta-Lactamases: Enhancement of Activity of Multiple Antibiotics Against Isogenic Strains Expressing Single {beta}

QPX7728 is an ultra-broad-spectrum boronic acid beta-lactamase inhibitor with potent inhibition of key serine and metallo beta-lactamases observed in biochemical assays. Microbiological studies using characterized strains were used to provide a comprehensive characterization of the spectrum of beta-lactamase inhibition by QPX7728. The MIC of multiple IV only (ceftazidime, piperacillin, cefepime, ceftolozane and meropenem) and orally bioavailable (ceftibuten, cefpodoxime, tebipenem) antibiotics alone and in combination with QPX7728 (4 μg/ml), as well as comparator agents, were determined against the panels of laboratory strains of P. aeruginosa and K. pneumoniae expressing over 55 diverse serine and metallo beta-lactamases. QPX7728 significantly enhanced the potency of antibiotics against the strains expressing Class A extended spectrum beta-lactamases (CTX-M, SHV, TEM, VEB, PER) and carbapenemases (KPC, SME, NMC-A, BKC-1), consistent with beta-lactamase inhibition demonstrated in biochemical assays. It also inhibits both plasmidic (CMY, FOX, MIR, DHA) and chromosomally encoded (P99, PDC, ADC) Class C beta-lactamases and Class D enzymes including carbapenemases such as OXA-48 from Enterobacteriaceae and OXA enzymes from Acinetobacter baumannii (OXA-23/24/72/58). QPX7728 is also a potent inhibitor of many class B metallo beta-lactamases (NDM, VIM, CcrA1, IMP, GIM but not SPM or L1). Addition of QPX7728 (4 μg/ml) reduced the MICs in a majority of strains to the level observed for the vector alone control, indicative of complete beta-lactamase inhibition. The ultra-broad-spectrum beta-lactamase inhibition profile makes QPX7728 a viable candidate for further development.




ai

Efficacy of bedaquiline, alone or in combination with imipenem, against Mycobacterium abscessus in C3HeB/FeJ mice [Experimental Therapeutics]

Mycobacterium abscessus lung infections remain difficult to treat. Recent studies have recognized the power of new combinations of antibiotics such as bedaquiline and imipenem although in vitro data have questioned this combination. We report that the efficacy of the bedaquiline plus imipenem treatment relies essentially on the activity of bedaquiline in a C3HeB/FeJ mice model of infection with a rough variant of M. abscessus. The addition of imipenem contributed at clearing the infection in the spleen.




ai

In vitro and in vivo study on the synergistic effect of minocycline and azoles against pathogenic fungi [Susceptibility]

In vitro and in vivo interactions of minocycline and azoles including itraconazole, voriconazole, and posaconazole against filamentous pathogenic fungi were investigated. A total of 56 clinical isolates were studied in vitro via broth microdilution checkerboard technique, including 20 strains of Aspergillus fumigatus, 7 strains of A. flavus, 16 strains of Exophiala dermatitidis, 10 strains of Fusarium solani and 3 strain s of F. oxysporum. The results revealed that minocycline individually did not exhibit any significant antifungal activity against all tested strains. However, favorable synergy of minocycline with itraconazole, voriconazole, or posaconazole were observed against 34 (61%), 28 (50%), and 38 (69%) isolates, respectively, including azole resistant A. fumigatus and Fusarium spp. with inherently high MICs of azoles. Synergistic combinations resulted in 4 fold to 16-fold reduction of effective MICs of minocycline and azoles. No antagonism was observed. In vivo effect of minocycline-azole combinations were evaluated by survival assay in Galleria mellonella model infected with E. dermatitidis strain BMU00034, F. solani strain FS9, A. fumigatus strain AF293, AFR1 and AFR2 . Minocycline acted synergistically with azoles and significantly increased larvae survival in all isolates (P<0.001), including azole resistant A. fumigatus and azole-inactive Fusarium spp.. In conclusion, the results suggested that minocycline combined with azoles may help to enhance the antifungal susceptibilities of azoles against pathogenic fungi and had the potential to overcome azole resistance issues.




ai

The Added Value of Longitudinal Imaging for Preclinical In vivo Efficacy Testing of Therapeutic Compounds against Cerebral Cryptococcosis [Experimental Therapeutics]

Brain infections with Cryptococcus neoformans are associated with significant morbidity and mortality. Cryptococcosis typically presents as meningoencephalitis or fungal mass lesions called cryptococcomas. Despite frequent in vitro discoveries of promising novel antifungals, the clinical need for drugs that can more efficiently treat these brain infections remains. A crucial step in drug development is the evaluation of in vivo drug efficacy in animal models. This mainly relies on survival studies or post-mortem analyses in large groups of animals, but these techniques only provide information on specific organs of interest at predefined time points. In this proof-of-concept study, we validated the use of non-invasive preclinical imaging to obtain longitudinal information on the therapeutic efficacy of amphotericin B or fluconazole monotherapy in meningoencephalitis and cryptococcoma mouse models. Bioluminescence imaging (BLI) enabled the rapid in vitro and in vivo evaluation of drug efficacy while complementary high-resolution anatomical information obtained by magnetic resonance imaging (MRI) of the brain allowed a precise assessment of the extent of infection and lesion growth rates. We demonstrated a good correlation between both imaging readouts and the fungal burden in various organs. Moreover, we identified potential pitfalls associated with the interpretation of therapeutic efficacy based solely on post-mortem studies, demonstrating the added value of this non-invasive dual imaging approach compared to standard mortality curves or fungal load endpoints. This novel preclinical imaging platform provides insights in the dynamic aspects of the therapeutic response and facilitates a more efficient and accurate translation of promising antifungal compounds from bench to bedside.




ai

Novel ionophores active against La Crosse virus identified through rapid antiviral screening [Antiviral Agents]

Bunyaviruses are significant human pathogens, causing diseases ranging from hemorrhagic fevers to encephalitis. Among these viruses, La Crosse virus (LACV), a member of the California serogroup, circulates in the eastern and midwestern United States. While LACV infection is often asymptomatic, dozens of cases of encephalitis are reported yearly. Unfortunately, no antivirals have been approved to treat LACV infection. Here, we developed a method to rapidly test potential antivirals against LACV infection. From this screen, we identified several potential antiviral molecules, including known antivirals. Additionally, we identified many novel antivirals that exhibited antiviral activity without affecting cellular viability. Valinomycin, a potassium ionophore, was among our top targets. We found that valinomycin exhibited potent anti-LACV activity in multiple cell types in a dose-dependent manner. Valinomycin did not affect particle stability or infectivity, suggesting that it may preclude virus replication by altering cellular potassium ions, a known determinant of LACV entry. We extended these results to other ionophores and found that the antiviral activity of valinomycin extended to other viral families including bunyaviruses (Rift Valley fever virus, Keystone virus), enteroviruses (Coxsackievirus, rhinovirus), flavirivuses (Zika), and coronaviruses (HCoV-229E and MERS-CoV). In all viral infections, we observed significant reductions in virus titer in valinomycin-treated cells. In sum, we demonstrate the importance of potassium ions to virus infection, suggesting a potential therapeutic target to disrupt virus replication.

Importance No antivirals are approved for the treatment of bunyavirus infection. The ability to rapidly screen compounds and identify novel antivirals is one means to accelerate drug discovery for viruses with no approved treatments. We used this approach to screen hundreds of compounds against La Crosse virus, an emerging bunyavirus that causes significant disease, including encephalitis. We identified several known and previously unidentified antivirals. We focused on a potassium ionophore, valinomycin, due to its promising in vitro antiviral activity. We demonstrate that valinomycin, as well as a selection of other ionophores, exhibits activity against La Crosse virus as well as several other distantly related bunyaviruses. We finally observe that valinomycin has activity against a wide array of human viral pathogens, suggesting that disrupting potassium ion homeostasis with valinomycin may be a potent host pathway to target to quell virus infection.




ai

Therapeutic efficacy of a mixed formulation of conventional and PEGylated liposomes containing meglumine antimoniate, combined with allopurinol, in dogs naturally infected with Leishmania infantum [Experimental Therapeutics]

Treatment of dogs naturally infected with Leishmania infantum using meglumine antimoniate (MA) encapsulated in conventional liposomes (LC) in association with allopurinol has been previously reported to promote marked reduction in the parasite burden in the main infection sites. Here, a new assay in naturally infected dogs was performed using a novel liposome formulation of MA consisting of a mixture of conventional and long-circulating (PEGylated) liposomes (LCP), with expected broader distribution among affected tissues of the mononuclear phagocyte system. Experimental groups of naturally infected dogs were as follows: LCP+Allop, receiving LCP intravenously as 2 cycles of 6 doses (6.5 mg Sb/kg/dose) at 4-day intervals, plus allopurinol at 30 mg/kg/12 h p.o. during 130 days; LC+Allop, receiving LC intravenously as 2 cycles of 6 doses (6.5 mg Sb/kg/dose), plus allopurinol during 130 days; Allop, treated with allopurinol only; non-treated control. Parasite loads were evaluated by quantitative PCR in liver, spleen and bone marrow and by immunohistochemistry in the ear skin, before, just after treatment and 4 months later. LCP+Allop and LC+Allop groups, but not the Allop group, showed significant suppression of the parasites in the liver, spleen and bone marrow 4 months after treatment, compared to the pre-treatment period or the control group. Only LCP+Allop group showed significantly lower parasite burden in the skin, in comparison to the control group. On the basis of clinical staging and parasitological evaluations, LCP formulation exhibited a more favorable therapeutic profile, when compared to LC one, being therefore promising for treatment of canine visceral leishmaniasis.




ai

Pharmacokinetic-Pharmacodynamic Characterization of Omadacycline Against Haemophilus influenzae Using a One-Compartment In Vitro Infection Model [Pharmacology]

Omadacycline is a novel aminomethylcycline with activity against Gram-positive and -negative organisms, including Haemophilus influenzae, which is one of the leading causes of community-acquired bacterial pneumonia (CABP). The evaluation of antimicrobial agents against H. influenzae using standard murine infection models is challenging due to the low pathogenicity of this species in mice. Therefore, 24-hour dose-ranging studies using a one-compartment in vitro infection model were undertaken with the goal of characterizing the magnitude of the ratio of the area under the concentration-time curve (AUC) to the MIC (AUC/MIC ratio) associated with efficacy for a panel of five clinical H. influenzae isolates. These five isolates, which had MIC values of 1 or 2 mg/L, were exposed to omadacycline total-drug epithelial lining fluid (ELF) concentration-time profiles based on those observed in healthy volunteers following intravenous omadacycline administration. Relationships between change in log10 colony forming units (CFU) from baseline at 24 hours and total-drug ELF AUC/MIC ratio for each isolate and the isolates pooled together were evaluated using Hill-type models and non-linear least squares regression. As evidenced by the high coefficient of determination (r2) of 0.88 to 0.98, total-drug ELF AUC/MIC ratio described the data well for each isolate and the isolates pooled together. The median total-drug ELF AUC/MIC ratio associated with net bacterial stasis and 1- and 2-log10 CFU/mL reductions from baseline at 24 hours was 6.91, 8.91, and 11.1, respectively. These data were useful to support the omadacycline dosing regimens selected for the treatment of patients with CABP, as well as susceptibility breakpoints for H. influenzae.




ai

Population pharmacokinetics of piperacillin following continuous infusion in critically ill patients: Impact of renal function on target attainment [Clinical Therapeutics]

Pharmacokinetic changes are often seen in patients with severe infections. Administration by continuous infusion has been suggested to optimize antibiotic exposure and pharmacokinetic/pharmacodynamic (PK/PD) target attainment for β-lactams. In an observational study, unbound piperacillin concentrations (n=196) were assessed in 78 critically ill patients following continuous infusion of piperacillin/tazobactam (ratio 8:1). The initial dose of 8, 12 or 16 g (piperacillin component) was determined by individual creatinine clearance (CRCL). Piperacillin concentrations were compared to the EUCAST clinical breakpoint MIC for Pseudomonas aeruginosa (16 mg/L), and the following PK/PD targets were evaluated: 100% fT>1xMIC and 100% fT>4xMIC. A population pharmacokinetic model was developed using NONMEM 7.4.3 consisting of a one-compartment disposition model with linear elimination separated into non-renal and renal (linearly increasing with patient CRCL) clearances. Target attainment was predicted and visualized for all individuals based on the utilized CRCL dosing algorithm. The target of 100% fT>1xMIC was achieved for all patients based on the administered dose, but few patients achieved the target of 100% fT>4xMIC. Probability of target attainment for a simulated cohort of patients showed, that increasing the daily dose by 4 g increments (piperacillin component) did not result in substantially improved target attainment for the 100% fT>4xMIC target. To conclude, in patients with high CRCL combined with high-MIC bacterial infections, even a CI regimen with a daily dose of 24 g may be insufficient to achieve therapeutic concentrations.




ai

Efficacy of neuraminidase inhibitors against H5N6 highly pathogenic avian influenza virus in a non-human primate model [Antiviral Agents]

Attention has been paid to H5N6 highly pathogenic avian influenza virus (HPAIV) because of its heavy burden on the poultry industry and human mortality. Since an influenza A virus carrying N6 neuraminidase (NA) has never spread in humans, the potential for H5N6 HPAIV to cause disease in humans and the efficacy of antiviral drugs against the virus need to be urgently assessed. We used non-human primates to elucidate the pathogenesis of H5N6 HPAIV as well as to determine the efficacy of antiviral drugs against the virus. H5N6 HPAIV infection led to high fever in cynomolgus macaques. The lung injury caused by the virus was severe with diffuse alveolar damage and neutrophil infiltration. In addition, an increase in IFN-α showed an inverse correlation with virus titers during the infection process. Oseltamivir was effective for reducing H5N6 HPAIV propagation, and continuous treatment with peramivir reduced virus propagation and severity of symptoms in the early stage. This study also showed the pathologically severe lung injury states in the cynomolgus macaques infected with H5N6 HPAIV, even in those that received early antiviral drug treatments, indicating the need for close monitoring and the need for further studies on the virus pathogenicity and new antiviral therapies.




ai

Concurrent local delivery of diflunisal limits bone destruction but fails to improve systemic vancomycin efficacy during Staphylococcus aureus osteomyelitis [Clinical Therapeutics]

Staphylococcus aureus osteomyelitis is a debilitating infection of bone. Treatment of osteomyelitis is impaired by the propensity of invading bacteria to induce pathologic bone remodeling that may limit antibiotic penetration to the infectious focus. The nonsteroidal anti-inflammatory drug diflunisal was previously identified as an osteoprotective adjunctive therapy for osteomyelitis, based on the ability of this compound to inhibit S. aureus quorum sensing and subsequent quorum-dependent toxin production. When delivered locally during experimental osteomyelitis, diflunisal significantly limits bone destruction without affecting bacterial burdens. However, because diflunisal's "quorum-quenching" activity could theoretically increase antibiotic recalcitrance, it is critically important to evaluate this adjunctive therapy in the context of standard of care antibiotics. The objective of this study is to evaluate the efficacy of vancomycin to treat osteomyelitis during local diflunisal treatment. We first determined that systemic vancomycin effectively reduces bacterial burdens in a murine model of osteomyelitis, and identified a dosing regimen that decreases bacterial burdens without eradicating infection. Using this dosing scheme, we found that vancomycin activity is unaffected by the presence of diflunisal in vitro and in vivo. Similarly, locally-delivered diflunisal still potently inhibits osteoblast cytotoxicity in vitro and bone destruction in vivo in the presence of sub-therapeutic vancomycin. However, we also found that the resorbable polyurethane foams used to deliver diflunisal serve as a nidus for infection. Taken together, these data demonstrate that diflunisal does not significantly impact standard of care antibiotic therapy for S. aureus osteomyelitis, but also highlight potential pitfalls encountered with local drug delivery.




ai

Manogepix (APX001A) displays potent in vitro activity against human pathogenic yeast, but with an unexpected correlation to fluconazole MICs [Susceptibility]

Manogepix (APX001A) is the active moiety of the novel drug candidate fosmanogepix (APX001). We previously reported the broad-spectrum activity of manogepix but also observed a correlation between increased manogepix and fluconazole MICs. Here we extended this study and included isolates with acquired fluconazole resistance.

Isolates (n=835) were identified using CHROMagar, MALDI-TOF and, when needed, ITS-sequencing. EUCAST E.Def 7.3.1 susceptibility testing included manogepix, amphotericin B, anidulafungin, micafungin, fluconazole and voriconazole. Manogepix wildtype-upper-limit (WT-UL) values were established following EUCAST-principles for ECOFF setting allowing wildtype/non-wildtype classification. Drug-specific MIC correlations were investigated using Pearson's correlation.

Manogepix modal MICs were low (range 0.004-0.06 mg/L against 16/20 included species). Exceptions were C. krusei and C. inconspicua, and to a lesser extent C. kefyr and Pichia kluyveri. The activity was independent of Fks echinocandin hot-spot alterations (n=17). Adopting the WT-UL established for C. albicans, C. dubliniensis, C. glabrata, C. parapsilosis and C. tropicalis, 14/724 (1.9%) isolates were non-wildtype for manogepix. Twelve of these (85.7%) were also non-wildtype for fluconazole. A statistically significant correlation was observed between manogepix and fluconazole MICs for C. albicans, C. dubliniensis, C. glabrata, C. parapsilosis and C. tropicalis (Pearson r=0.401-0.575), but not between manogepix and micafungin or amphotericin B MICs for any species except C. tropicalis (r=0.519 for manogepix versus micafungin).

Broad-spectrum activity was confirmed for manogepix against contemporary yeast. However, a 1-4 two-fold-dilution increase in manogepix MICs is observed in a subset of isolates with acquired fluconazole resistance. Further studies on the potential underlying mechanism and implication for optimal dosing are warranted.




ai

Identification of antiviral drug candidates against SARS-CoV-2 from FDA-approved drugs [Antiviral Agents]

Drug repositioning is the only feasible option to address the COVID-19 global challenge immediately. We screened a panel of 48 FDA-approved drugs against SARS-CoV-2 which were pre-selected by an assay of SARS-CoV and identified 24 potential antiviral drug candidates against SARS-CoV-2 infection. Some drug candidates showed very low micromolar IC50s and in particular, two FDA-approved drugs - niclosamide and ciclesonide – were notable in some respects.




ai

Evaluation of leishmanicidal activity of an in silico screened novel inhibitor against ascorbate peroxidase of Leishmania donovani [Mechanisms of Action]

Peroxidases are a group of heterogeneous family of enzyme that plays diverse biological functions. Ascorbate peroxidase is a redox enzyme that is reduced by trypanothione, which plays a central role in the redox defence system of Leishmania. In view of developing new and novel therapeutics, we have performed in silico studies in order to search for ligand library and identification of new drug candidates and its physiological role against promastigotes and intracellular amastigotes of Leishmania donovani. Our results demonstrated that the selected inhibitor ZINC96021026 has significant anti-leishmanial effect and effectively killed both free and intracellular forms of the parasite. ZINC96021026 was found to be identical to ML-240, a selective inhibitor of Valosin-containing protein (VCP) or p97, a member of AAA-ATPase protein family which was derived from the scaffold of DBeQ, targeting the D2-ATPase domain of the enzyme. ZINC96021026 (ML-240) thus have broad range of cellular functions, thought to be derived from its ability to unfold proteins or disassemble protein complexes besides inhibiting the ascorbate peroxidase activity. ML-240 may inhibits the parasite's ascorbate peroxidase leading to extensive apoptosis and inducing generation of reactive oxygen species. Taken together, our results demonstrated that ML-240 could be an attractive therapeutic option for treatment against leishmaniasis.




ai

Activity of epigenetic inhibitors against Plasmodium falciparum asexual and sexual blood stages. [Susceptibility]

Earlier genetic and inhibitor studies have shown that epigenetic regulation of gene expression is critical for malaria parasite survival in multiple life stages and a promising target for new anti-malarials. We therefore evaluated the activity of 350 diverse epigenetic inhibitors against multiple stages of Plasmodium falciparum. We observed ≥90% inhibition at 10 μM for 28% of compounds against asexual blood stages and early gametocytes, of which a third retained ≥90% inhibition at 1 μM.




ai

Save 30 Percent on Keeper, Never Click 'Forgot Password' Again

The password-fatigued masses will be pleased to find Keeper's new 30 percent off deal, which brings it down to $20.99 per year from its typical $29.99.




ai

New Coronavirus Strain? Nope, Just Hackers Trying to Spread Malware

The hackers have been using files and emails that warn about a new coronavirus strain to trick users into opening them. Doing so can secretly deliver malware to the victim's machine.