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RDC : Les leçons du scrutin présidentiel

Trois semaines après la réélection contestée de Joseph Kabila en République démocratique du Congo (RDC), Thierry Vircoulon, responsable de l'Afrique centrale à l'International Crisis Group dresse un premier bilan des élections congolaises.




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Imaginación para salvar República Centroafricana. Cómo actuar con rapidez y eficacia para evitar la somalización del país.

Los conflictos en los países pequeños suelen agravarse debido a la indiferencia internacional. Sin embargo, en el caso de la República Centroafricana (RCA), el problema es ligeramente distinto. Hay una importante presencia internacional en este Estado, pero los actores principales han decidido mantenerse al margen y esperar en vez de intervenir activamente en la crisis.




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Gesucht: Neue Ideen für alte Probleme

Die Zentralafrikanische Republik trägt einen nüchternen, doch gerade in jüngster Zeit allzu treffenden Namen. Denn sie scheint tatsächlich zum Zentrum oder zumindest zum Ballungsraum all der vielfältigen Probleme geworden zu sein, unter denen der Kontinent seit langem leidet und von denen sich aber mittlerweile viele afrikanische Länder befreien können. Da sind die Konflikte um den Abbau wertvoller Ressourcen, besonders von Diamanten. Aus einer kleinen Elite ist eine Reihe unfähiger politischer Führer hervorgegangen. Es mehren sich Konflikte zwischen nomadischen Stämmen und der sesshaften Bevölkerung, was Ursachen auch im Klimawandel hat, und zu neuen Konkurrenzen zwischen den beiden Bevölkerungsteilen führt. Aus Rivalitäten zwischen ethnischen Gemeinschaften erwuchsen blutige Kämpfe und neue Feindschaften: die altbekannte, berüchtigte Kombination von historischen Altlasten und politischem Opportunismus schuf Konflikte auf der Grundlage religiöser Gruppenzugehörigkeit, wie jetzt zwischen Christen und Muslimen. Die schwierige Lage hat dem Land international eine erhöhte, aber nicht immer nützliche Aufmerksamkeit verschafft: des Nachbarlands Tschad, der Zentralafrikanischen Wirtschaftsgemeinschaft, von der Afrikanischen Union und von den Vereinten Nationen. Außerdem von multilateralen und Nicht­regierungs­organisationen, von der ehemaligen Kolonialmacht Frankreich und von weiteren internationalen Akteuren wie den Vereinigten Staaten, Südafrika, der Europäischen Union und unlängst auch von Deutschland. In kürzester Zeit ist die Zentralafrikanische Republik zu trauriger Berühmtheit gelangt. Doch so stark die Aufmerksamkeit auch gestiegen ist, so viel Wissen ist über dieses Land nachzuholen – Wissen, das man braucht, um vernünftig zu handeln. Mein Kollege Thibaud Lesueur und ich haben in den vergangenen drei Jahren viele Monate in der Zen­tralafrikanischen Republik verbracht. Wir konnten vor Ort beobachten, wie der Staat erst allmählich, dann rasant auseinanderfiel. Wir verfolgten, wie ein französisches Expeditionskorps, die Operation Sangaris, den afrikanischen Truppen zu Hilfe kam, um noch eine Spur von Ordnung vor dem drohenden Chaos zu retten, wie es nur eine gut ausgestattete Berufsarmee kann. Wir sahen, wie aus der einst stabilen Bevölkerung eine Generation plündernder Krieger hervorging. Und wir erlebten, wie aus Bangui, der Hauptstadt am Ubangi Fluss mit 750 000 Einwohnern, ein Schauplatz von Lynchjustiz wurde, was 90 Prozent der muslimischen Bevölkerung in die Flucht trieb. Ein Opfer dieser Selbstjustiz wurde auch Jean-Emmanuel Ndjaroua, ein Mitglied des nationalen Übergangsrats. Er machte im Februar den verhängnisvollen Fehler, öffentlich zu Toleranz und Frieden aufzurufen, und wurde auf offener Straße erschossen. Die große Herausforderung besteht nun darin zu verhindern, dass aus Tausenden viele Zehntausende Tote werden. Noch besteht Hoffnung, dass ein solches Blutvergießen vermieden werden kann. Die neue Regierung unter Präsidentin Catherine Samba-Panza hat Potenzial, und die von der Zentralafrikanischen Wirtschaftsgemeinschaft zügig entsandten – aber zu schwachen – Truppen hat man durch eine hoffentlich zielgerichtetere Mission unter Führung der ­Afrikanischen Union ersetzt. Unter der Federführung Frankreichs hat der UN-Sicherheitsrat am 10. April eine Resolution zum Einsatz einer neuen UN-Friedensmission beschlossen. Diese sieht vor, dass die Truppen der Afrikanischen Union im September 2014 unter das Kommando der Vereinten Nationen gestellt werden und die Zahl der internationalen Friedenssoldaten nahezu verdoppelt wird. Die Europäische Union hat derweil für Mai die Stationierung einer „Überbrückungsmission“ angekündigt. Diese Einsatzverpflichtungen sind mehr als bloße Versprechen, aber sie bleiben dennoch hinter dem zurück, was man als entschiedenes Handeln bezeichnen würde. Was also ist zu tun? Vertrauen zwischen den Religionen Es ist entscheidend, zwischen den Bevölkerungsteilen wieder Vertrauen aufzubauen. Der Imam, der Erzbischof und Vertreter der anderen christlichen Kirchen in Bangui arbeiten bereits eng zusammen, aber ihre Anstrengungen sind bisher auf die Hauptstadt begrenzt – aus der fast alle Muslime geflohen sind. Ein interkonfessioneller Dialog und eine Versöhnungskampagne müssen an der Basis beginnen und mithilfe der Übergangsregierung und ihrer internationalen Unterstützer auf die Provinzen ausgeweitet werden. Die Bausteine dafür existieren bereits – im Westen des Landes beispielsweise sind die verbliebenen muslimischen Flüchtlinge mehrheitlich bei christlichen Missionen untergekommen. Erinnern wir uns: Religiöse Gruppenzugehörigkeiten sind noch nicht lange eine Konfliktursache in der Zentralafrikanischen Republik. Zwei frühere Präsidenten, Bokassa und Patassé, konvertierten zum Islam, und diverse ethnische Gruppen setzen sich aus Christen und Muslimen zusammen. Bis heute sind im vorwiegend muslimischen nordöstlichen Distrikt, in dem sich auch viele aus Bangui vertriebene Krieger aufhalten, die Christen des Saraa-Stammes (zu dem auch viele Muslime gehören) nicht angegriffen worden, und auch nicht das zahlenmäßig große christliche Volk der Banda in Bria. In Bangui entstand als Reaktion auf die Morde eine Nichtregierungsorganisation, Les Frères Centrafricains, die über Aufkleber an Taxis zur Versöhnung aufrief. Junge Christen taten sich zusammen, um gemeinsam Moscheen vor Angriffen zu beschützen. Ankurbelung der Wirtschaft Die Wirtschaft des Landes muss neu belebt werden. Die wichtigsten Exportgüter des Landes sind Holz und Diamanten – und der Handel mit diesen Gütern setzt Sicherheit voraus. Von den fünf privaten Firmen, die bislang die Holzindustrie dominierten, arbeiten nur noch zwei. Ein Angestellter vor Ort erzählte uns, wie sein Betrieb zuerst Anfang 2013 von der Präsidentengarde durchsucht wurde, daraufhin von den muslimisch dominierten Séléka-Rebellen und schließlich von der prochristlichen Anti-Balaka-Bewegung, und wie alle von ihnen Fahrzeuge stahlen. Der Diamantenhandel ist ebenfalls in eine schwere Schieflage geraten, denn die Händler waren fast ausschließlich Muslime. Mit Beginn des Gegenaufstands der Anti-Balaka-Milizen flohen sie aus den Städten, ihre Geschäfte wurden geplündert. Auf lange Sicht muss der Staat seine Kontrolle über die Diamantenfelder wiederherstellen und für die Sicherheit der Händler sowie die Transparenz der Handelswege sorgen. Dazu müssen Zivilbeamte und Polizei eingesetzt werden. Zum jetzigen Zeitpunkt können allein Friedenstruppen dafür sorgen, dass der Handel wieder sicher aufgenommen werden kann. Der bedeutendste nicht exportorientierte Wirtschaftszweig des Landes ist die landwirtschaftliche Selbstversorgung. Auch sie leidet unter der problematischen Sicherheitslage, besonders dort, wo Nomaden und Farmer in Konkurrenz um Land aufeinandertreffen. Die Wanderungen der nomadischen Hirten aus dem Tschad im Norden in die Zentralafrikanische Republik müssen dringend unter eine von allen Seiten ausgehandelte Regelung gestellt werden, von der Art, wie sie in Niger und Tschad bereits erfolgreich ist. In den größeren Städten des Landes muss indessen Arbeit für die ­dortigen Kämpfer geschaffen werden. In der Hauptstadt Bangui herrscht Gewalt. Dort wird neben einer verbesserten Sicherheitslage dringend mehr Beschäftigung für die Jugendlichen gebraucht, damit diese eine Alternative zu den Milizen finden, die ihnen bisher „Arbeit“ verschafft haben. Die Hauptstadt und weitere Landesteile leiden unter infrastrukturellen Problemen, die durch beschäftigungsintensive Maßnahmen zu lösen wären, für die ungelernte und angelernte Arbeitskräfte eingesetzt werden können. Sicherheit Um die Sicherheit im Land wiederherzustellen, muss die Afrikanische Union mit den Vereinten Nationen zusammenarbeiten. Die neue UN-­Resolution will aus den 6000 AU-Soldaten UN-Blauhelme machen, aber Streit um Zuständigkeiten könnte die Umsetzung erschweren. Auch Frankreich und die Europäische Union müssen eine Grundlage zur Zusammenarbeit finden. Hier wird vermutlich Deutschland eine Schlüsselrolle spielen. Die deutsche Koalitionsregierung hat den Versuch gestartet, die deutsch-französische ­Zusammenarbeit neu zu beleben, gerade auf außenpolitischem Gebiet. Im April sprach Bundeskanzlerin Angela Merkel von Frankreich und Deutschland als „Motor“ der Beziehungen zwischen der EU und Afrika, und Frankreichs Staatspräsident François Hollande unterstrich die „besondere Freundschaft“ beider Länder. Deutschland hat sich in bisher nicht gekannter Weise verpflichtet, in Mali und der Zentralafrikanischen Republik militärische Hilfen bereitzustellen – dies soll jeweils in enger Abstimmung mit Frankreich geschehen. Hinzu kommt eine bedeutsame entwicklungspolitische Unterstützung. Diese französisch-deutsche Führung hat aus einem vagen Plan ein handfestes Unternehmen gemacht; mittlerweile haben sich Estland, Finnland, Frankreich, Deutschland, Italien, Lettland, Litauen, Luxemburg, Polen, Portugal, Schweden, Spanien, Großbritannien sowie Georgien zur Mission bekannt. Der Großteil der Truppen wird von Estland, Frankreich, Georgien, Polen und Spanien gestellt. Deutschland legt seinen Schwerpunkt auf den strategischen Lufttransport, Großbritannien kümmert sich um logistische Fragen und Italien um die Technik. Selbst wenn die EU-Überbrückungsmission Realität wird und sich die Beziehungen zur Afrikanischen Union verbessern, wird es für den ­Sicherheitsrat der Vereinten Nationen und die UN-Organisationen sehr schwierig werden, erfolgreich eine Blauhelmtruppe in der Zentralafrikanischen Republik zu etablieren. Die Vereinten Nationen müssen die Frage beantworten, welche ihrer Mitgliedstaaten die Truppen stellen. Dabei sollten sie Tschad außen vor lassen. Das Land ist schon zu sehr in die Angelegenheiten der Zentralafrikanischen Republik verstrickt und hat seine Friedensmission Anfang April aufgekündigt, nachdem tschadische Soldaten beschuldigt wurden, für den Tod von Zivilisten verantwortlich zu sein. Die Befehlsgewalt über die Truppen wird zwar formal im September von der AU auf die UN übergehen. Aber praktisch wird die UN-Mission wahrscheinlich nicht vor Ende des Jahres in vollem Umfang anlaufen. Dabei erfordert die Entwaffnung der Milizen schnelles Handeln: Die verbliebene muslimische Bevölkerung in Bangui hat sich in der PK5 genannten muslimischen Enklave bewaffnet, und auch die Anti-Balaka-Milizen haben bisher keine Probleme, in der Hauptstadt an Waffen zu kommen – obwohl Tausende französische und afrikanische Friedenssoldaten durch die Straßen der Hauptstadt patrouillieren. Der muslimische Bürgermeister von Banguis drittem Bezirk, zu dem auch PK5 gehört, sagte im März: „Wenn wir PK5 verlassen, um in ein benachbartes Gebiet zu gehen, werden wir noch am gleichen Tag getötet.“ Die Franzosen verpassten im Dezember und Januar die Gelegenheit zur weitgehenden Entwaffnung der Séléka-Truppen, als diese noch in vier Lagern festgehalten wurden. Eine UN-Mission wird es mit der Entwaffnung nicht leichter haben als die Franzosen. Der Plan der Vereinten Nationen sieht vor, dass zuerst Soldaten stationiert werden, dann eine funktionierende Polizei aufgebaut wird, und dann ein Justizsystem. Die größten Schwachstellen sind die Soldaten und Geld: Von beiden gibt es viel zu wenig. Ein strategischer Fahrplan Die Übergangsregierung der Zentralafrikanischen Republik wie auch die internationale Gemeinschaft brauchen dringend einen Plan. Auf nationaler Ebene hatte es Ende vergangenen Jahres einen gegeben – einen mangelhaften, aber immerhin etwas. Die neue Regierung unter Catherine Samba-Panza ist die dritte Regierung innerhalb eines Jahres, aber sie ist vielversprechend. Die meisten wichtigen Ministerien sind mit Technokraten statt mit Parteigenossen besetzt. Präsidentin Samba-Panza hat bereits zu Beginn ihrer Amtszeit die Bedeutung von Justiz und Versöhnung betont. In einem Gespräch im April mit Crisis-Group-Präsidentin Louise Arbour bestätigte sie dies und unterstrich, dass ihr Land auf die Hilfe ausländischer Richter angewiesen sei, um ein effektives Justizsystem aufzubauen. All dies gibt Anlass zur Hoffnung. Was man jedoch für die erweiterte internationale Intervention braucht, sind eine kohärente Führung, strategisches Denken sowie einen gemeinsamen Stabilisierungsplan, der es der Übergangsregierung ermöglicht, mittel- und langfristige Prioritäten zu setzen. Die internationale Kontaktgruppe sowie der jüngste Bericht des UN-Generalsekretärs betonen zu Recht, wie wichtig es ist, die Sicherheit im Land wiederherzustellen, die staatlichen Dienste zu reaktivieren und Wahlen vorzubereiten. Aber sie gehen nicht auf die tieferliegenden Probleme ein, insbesondere nicht auf den wirtschaftlichen Niedergang, der die Hauptursache für den Staatszerfall ist. Jemand – beispielsweise die EU oder Mitglieder der internationalen Kontaktgruppe – sollte dafür sorgen, dass die bisherigen Entwicklungs- und Aufbauprogramme überprüft werden. Eine solche Überprüfung ist aus zwei Gründen wichtig: erstens um zu verstehen, was bei der Reform des Sicherheitssektors, bei der Entwaffnung und Demobilisierung von Kämpfern sowie den Reintegrationsmaßnahmen schiefgelaufen ist. Und zweitens, um eine Stabilisierungsstrategie zu entwerfen, die die Wirtschaft in den Mittelpunkt stellt und das bietet, was zurzeit fehlt: neue Ideen für alte Probleme sowie eine langfristige Roadmap für die nationalen und internationalen Akteure. Auf diese Weise hätte man eine Grundlage für die angedachte Geberkonferenz im späteren Jahresverlauf und es wäre einfacher, eine sinnvolle Aufgabenverteilung unter den internationalen Akteuren zu verabreden. Ein solcher Rahmen ist unverzichtbar, um der neuen Regierung ein Fundament für ihre Herkulesaufgabe zu geben, nämlich aus dem Land wieder einen funktionierenden Staat zu machen und die Wirtschaft wieder aufzubauen, die Grundlage eines jeden zukunftsfähigen Staates. Bei dieser Überprüfung sollte man keine Zeit verlieren. Denn wie schon in der Vergangenheit könnte das ­Interesse der in­ternationalen Gemeinschaft an der Zentralafrikanischen Republik wieder schwinden. Gerade dies war in der Vergangenheit ein Hauptgrund dafür, dass sich die Probleme des Landes so häufig wiederholten. Geschieht das nicht, könnte es passieren, dass die geplante Überbrückungsmission schon in einem Jahr nur noch eine vage Erinnerung ist, dass der Fall Zentralafrikanische Republik Frankreich aufgebürdet wird, dass die afrikanischen Staaten gerade genug Mittel haben, um einzuschreiten, aber zu wenig, um irgendetwas langfristig zu stabilisieren, und dass die Übergangsregierung dann nur noch damit beschäftigt ist, die Fassade eines Staates aufrechtzuerhalten.




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WITHDRAWN: Very strong synergy between modified RANTES and gp41 binding peptides leads to potent anti-HIV-1 activity [Article]

This article, published ahead of print on 28 July 2008, has been withdrawn by the authors. Although moderate synergy between P2-RANTES and C peptides can be observed with high statistical significance in cell fusion assays, this synergy was not able to be verified in HIV viral assays. The authors regret the overstatement of synergy and will revise the paper for publication at a later date.




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Significant efficacy of single low dose primaquine compared to stand alone artemisinin combination therapy in reducing gametocyte carriage in Cambodian patients with uncomplicated multidrug resistant Plasmodium falciparum malaria [Epidemiology and Surveil

Since 2012, single low dose of primaquine (SLDPQ, 0.25mg/kg) has been recommended with artemisinin-based combination therapies, as first-line treatment of acute uncomplicated Plasmodium falciparum malaria, to interrupt its transmission, especially in low transmission settings of multidrug, including artemisinin, resistance. Policy makers in Cambodia have been reluctant to implement this recommendation due to primaquine safety concerns and lack of data on its efficacy.

In this randomized controlled trial, 109 Cambodians with acute uncomplicated P. falciparum malaria received dihydroartemisinin-piperaquine (DP) alone or combined with SLDPQ on the first treatment day. Transmission-blocking efficacy of SLDPQ was evaluated on Days 0, 1, 2, 3, 7, 14, 21, 28 and recrudescence by reverse transcriptase polymerase chain reaction (RT-PCR) (gametocyte prevalence) and membrane-feeding assays with Anopheles minimus mosquitoes (gametocyte infectivity). Without the influence of recrudescent infections, DP+SLDPQ reduced gametocyte carriage 3 fold compared to DP. Of 48 patients tested on Day 0, only three patients were infectious to mosquitoes (~6%). Post-treatment, three patients were infectious: on D14 (3.5%, 1/29), and on the first and seventh day of recrudescence (8.3%, 1/12 for each); this overall low infectivity precluded our ability to assess its transmission blocking efficacy.

Our study confirms effective gametocyte clearance of SLDPQ when combined with DP in multidrug resistant P. falciparum and the negative impact of recrudescent infections due to poor DP efficacy. Artesunate-mefloquine (ASMQ) has replaced DP and ASMQ-SLDPQ has been deployed to treat all P. falciparum symptomatic patients to further support the elimination of multidrug resistant P. falciparum in Cambodia.




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Novel peptide from commensal Staphylococcus simulans blocks MRSA quorum sensing and protects host skin from damage [Mechanisms of Action]

Recent studies highlight the abundance of commensal coagulase-negative staphylococci (CoNS) on healthy skin. Evidence suggests that CoNS actively shape the skin immunological and microbial milieu to resist colonization or infection by opportunistic pathogens, including methicillin resistant Staphylococcus aureus (MRSA), in a variety of mechanisms collectively termed colonization resistance. One potential colonization resistance mechanism is the application of quorum sensing, also called the Accessory Gene Regulator (agr) system, which is ubiquitous among staphylococci. Common and rare CoNS make autoinducing peptides (AIPs) that function as MRSA agr inhibitors, protecting the host from invasive infection. In a screen of CoNS spent media we found that Staphylococcus simulans, a rare human skin colonizer and frequent livestock colonizer, released potent inhibitors of all classes of MRSA agr signaling. We identified three S. simulans agr classes, and have shown intraspecies cross-talk between non-cognate S. simulans agr types for the first time. The S. simulans AIP-I structure was confirmed, and the novel AIP-II and AIP-III structures were solved via mass spectrometry. Synthetic S. simulans AIPs inhibited MRSA agr signaling with nanomolar potency. S. simulans in competition with MRSA reduced dermonecrotic and epicutaneous skin injury in murine models. Addition of synthetic AIP-I also effectively reduced MRSA dermonecrosis and epicutaneous skin injury in murine models. These results demonstrate potent anti-MRSA quorum sensing inhibition by a rare human skin commensal, and suggest that cross-talk between CoNS and MRSA may be important in maintaining healthy skin homeostasis and preventing MRSA skin damage during colonization or acute infection.




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Repurposing the antiamoebic drug diiodohydroxyquinoline for treatment of Clostridioides difficile infections [Experimental Therapeutics]

Clostridioides difficile, the leading cause of nosocomial infections, is an urgent health threat worldwide. The increased incidence and severity of disease, the high recurrence rates, and the dearth of effective anticlostridial drugs have created an urgent need for new therapeutic agents. In an effort to discover new drugs for treatment of Clostridioides difficile infections (CDIs), we investigated a panel of FDA-approved antiparasitic drugs against C. difficile and identified diiodohydroxyquinoline (DIHQ), an FDA-approved oral antiamoebic drug. DIHQ exhibited potent activity against 39 C. difficile isolates, inhibiting growth of 50% and 90% of these isolates at the concentrations of 0.5 μg/mL and 2 μg/mL, respectively. In a time-kill assay, DIHQ was superior to vancomycin and metronidazole, reducing a high bacterial inoculum by 3-log10 within six hours. Furthermore, DIHQ reacted synergistically with vancomycin and metronidazole against C. difficile in vitro. Moreover, at subinhibitory concentrations, DIHQ was superior to vancomycin and metronidazole in inhibiting two key virulence factors of C. difficile, toxin production and spore formation. Additionally, DIHQ did not inhibit growth of key species that compose the host intestinal microbiota, such as Bacteroides, Bifidobacterium and Lactobacillus spp. Collectively, our results indicate that DIHQ is a promising anticlostridial drug that warrants further investigation as a new therapeutic for CDIs.




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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.




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Structural basis of reduced susceptibility to ceftazidime-avibactam and cefiderocol in Enterobacter cloacae due to AmpC R2 loop deletion [Mechanisms of Resistance]

Ceftazidime–avibactam and cefiderocol are two of the latest generation β-lactam agents that possess expanded activity against highly drug-resistant bacteria, including carbapenem-resistant Enterobacterales. Here we show that structural changes in AmpC β-lactamases can confer reduced susceptibility to both agents. A multidrug-resistant Enterobacter cloacae clinical strain (Ent385) was found to be resistant to ceftazidime–avibactam and cefiderocol without prior exposure to either agent. The AmpC β-lactamase of Ent385 (AmpCEnt385) contained an alanine–proline deletion at positions 294–295 (A294_P295del) in the R2 loop. AmpCEnt385 conferred reduced susceptibility to ceftazidime–avibactam and cefiderocol when cloned into Escherichia coli TOP10. Purified AmpCEnt385 showed increased hydrolysis of ceftazidime and cefiderocol compared with AmpCEnt385Rev, in which the deletion was reverted. Comparisons of crystal structures of AmpCEnt385 and AmpCP99, the canonical AmpC of E. cloacae, revealed that the two-residue deletion in AmpCEnt385 induced drastic structural changes of the H-9 and H-10 helices and the R2 loop, which accounted for the increased hydrolysis of ceftazidime and cefiderocol. The potential for a single mutation in ampC to confer reduced susceptibility to both ceftazidime–avibactam and cefiderocol requires close monitoring.

Importance Ceftazidime–avibactam and cefiderocol are newly approved β-lactam agents that possess broad spectrum activity against multidrug-resistant (MDR) Gram-negative bacteria. We show here that a two amino-acid deletion in the chromosomal AmpC β-lactamase, identified in a clinical strain of Enterobacter cloacae, confers reduced susceptibility to both agents. By crystallographic studies of free and drug-bound forms of enzyme, we demonstrate that this deletion in AmpC induces slanting of the H-9 helix that is directly connected with the R2 loop, and disappearance of the H-10 helix, is directly responsible for increased hydrolysis of ceftazidime and cefiderocol. These findings provide novel insights into how MDR Gram-negative bacteria may evolve their β-lactamases to survive selective pressure from these newly developed β-lactam agents.




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Epidemiological study on prevalence, serovar diversity, multi-drug resistance and CTX-M-type extended-spectrum {beta}-lactamases of Salmonella spp. from patients with diarrhea, food of animal origin, and pets in several provinces of China [Epidemiology an

A total of 2,283 Salmonella spp. isolates were recovered from 18,334 samples including patients with diarrhea, food of animal origin and pets across 5 provinces of China. The highest prevalence of Salmonella spp. was detected in chicken meats (39.3%, 486/1,237). Fifteen serogroups and 66 serovars were identified, with Typhimurium and Enteritidis being the most dominant. Most (85.5%, 1,952/2,283) isolates exhibited resistant to ≥ 1 antimicrobial and 56.4% were multi-drug resistant (MDR). A total of 222 isolates harbored extended-spectrum β-lactamases (ESBLs), 200 of which were CTX-M-type that were mostly detected from chicken meat and turtle fecal. Overall, eight blaCTX-M genes were identified, with blaCTX-M-65, blaCTX-M-123, blaCTX-M-14, blaCTX-M-79, and blaCTX-M-130 being the most prevalent. Totally, 166 of the 222 ESBL-producing isolates had amino acid substitutions in GyrA (S83Y, S83F, D87G, D87N, and D87Y) and ParC (and S80I), whilst the PMQR-encoding genes oqxA/B, qepA, and qnrB/S were detected in almost all isolates. Of the fifteen sequence types (STs) identified in the 222 ESBLs, ST17, ST11, ST34, and ST26 ranked among the top 5 in the number of isolates. Our study revealed considerable serovars diversity, high prevalence of co-occurrence of MDR determinants, including CTX-M-type ESBLs, QRDRs mutations and PMQR genes. This is the first report of CTX-M-130 Salmonella spp. from patients with diarrhea and QRDRs mutations from turtle fecal samples. Our study emphasizes the importance of actions, both in the health care settings and in the veterinary medicine sector, to control the dissemination of MDR, especially the CTX-M Salmonella spp. isolates.




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Development of Novel Anti-influenza Thiazolides with Relatively Broad-spectrum Antiviral Potentials [Antiviral Agents]

Seasonal and pandemic influenza causes 650,000 deaths annually in the world. The emergence of drug-resistance to specific anti-influenza drugs such as oseltamivir and baloxavir marboxil highlights the urgency of novel anti-influenza chemical entity discovery. In this study, we report a series of novel thiazolides derived from an FDA-approved drug nitazoxanide with antiviral activity against influenza and a broad range of viruses. The preferred candidates 4a and 4d showed significantly enhanced anti-influenza potentials with 10-fold improvement, compared with nitazoxanide, and were effective against a variety of influenza subtypes including oseltamivir-resistant strains. Notably, the combination using of compounds 4a/4d and oseltamivir carboxylate or zanamivir displayed synergistic antiviral effect against oseltamivir-resistant strain. Mode of action analysis demonstrated that compounds 4a/4d acted at the late phase of viral infection cycle through inhibiting viral RNA transcription and replication. Further experiments showed that treatment with compounds 4a/4d significantly inhibited influenza virus infection in human lung organoids, suggesting the druggability of the novel thiazolides. In-depth transcriptome analysis revealed a series of up-regulated cellular genes that may contribute to the antiviral activities of 4a/4d. Together, our study pointed the optimization direction of nitazoxanide as anti-influenza drug, and discovered two novel-structured candidates 4a/4d with relatively broad-spectrum antiviral potential.




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Genetic Mutations Associated with Isoniazid Resistance in Mycobacterium tuberculosis in Mongolia [Epidemiology and Surveillance]

Globally, mutations in the katG gene account for the majority of isoniazid-resistant strains of Mycobacterium tuberculosis. Buyankhishig et al analyzed a limited number of Mycobacterium tuberculosis strains in Mongolia and found that isoniazid resistance was mainly attributable to inhA mutations. The GenoType® MTBDRplus assay was performed for isolates collected in the First National Tuberculosis Prevalence Survey and the Third Anti-Tuberculosis Drug Resistance Survey to investigate genetic mutations associated with isoniazid resistance in Mycobacterium tuberculosis in Mongolia. Of the 409 isoniazid-resistant isolates detected by the GenoType® MTBDRplus assay, 127 (31.1%) were resistant to rifampicin, 294 (71.9%) had inhA mutations without katG mutations, 113 (27.6%) had katG mutations without inhA mutations, and two (0.5%) strains had mutations in both the inhA and katG genes. Of the 115 strains with any katG mutation, 114 (99.1%) had mutations in codon 315 (S315T). Of the 296 trains with any inhA mutation, 290 (98.0%) had a C–15T mutation. The proportion of isoniazid-resistant strains with katG mutations was 25.3% among new cases and 36.2% among retreatment cases (p=0.03), as well as 17.0% among rifampicin-susceptible strains and 52.8% among rifampicin-resistant strains (p<0.01). Rifampicin resistance was significantly associated with the katG mutation (adjusted odds ratio 5.36, 95% CI 3.3–8.67, p<0.001). Mutations in inhA predominated in isoniazid-resistant tuberculosis in Mongolia. However, the proportion of katG mutations in isolates from previously treated cases was higher than that among new cases, and that in cases with rifampicin resistance was higher than that in cases without rifampicin resistance.




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Prediction of antibiotic susceptibility for urinary tract infection in a hospital setting [Epidemiology and Surveillance]

Objectives: Empiric antibiotic prescribing can be supported by guidelines and/or local antibiograms, but these have limitations. We sought to use data from a comprehensive electronic health record to use statistical learning to develop predictive models for individual antibiotics that incorporate patient-, and hospital-specific factors. This paper reports on the development and validation of these models on a large retrospective cohort.

Methods: This is a retrospective cohort study including hospitalized patients with positive urine cultures in the first 48 hours of hospitalization at a 1500 bed, tertiary care hospital over a 4.5 year period. All first urine cultures with susceptibilities were included. Statistical learning techniques, including penalized logistic regression, were used to create predictive models for cefazolin, ceftriaxone, ciprofloxacin, cefepime, and piperacillin-tazobactam. These were validated on a held-out cohort.

Results: The final dataset used for analysis included 6,366 patients. Final model covariates included demographics, comorbidity score, recent antibiotic use, recent antimicrobial resistance, and antibiotic allergies. Models had acceptable to good discrimination in the training dataset and acceptable performance in the validation dataset, with a point estimate for area under the receiver operating characteristic curve (AUC) that ranged from 0.65 for ceftriaxone to 0.69 for cefazolin. All models had excellent calibration.

Conclusion: In this study we used electronic health record data to create predictive models to estimate antibiotic susceptibilities for UTIs in hospitalized patients. Our models had acceptable performance in a held-out validation cohort.




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Emergence of Mycobacterium leprae rifampicin resistance evaluated by whole-genome sequencing after 48 years of irregular treatment [Epidemiology and Surveillance]

A case of M. leprae rifampicin resistance after irregular anti-leprosy treatments since 1971 is reported. Whole-genome sequencing from four longitudinal samples indicated relapse due to acquired rifampicin resistance and not to reinfection with another strain. A putative compensatory mutation in rpoC was also detected. Clinical improvement was achieved using an alternative therapy.




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Impact of vanA-positive Enterococcus faecium exhibiting diverse susceptibility phenotypes to glycopeptides on 30-day mortality of patients with a bloodstream infection [Epidemiology and Surveillance]

Introduction: This study was performed to evaluate the impacts of vanA-positivity of Enterococcus faecium (EFM) exhibiting diverse susceptibility phenotypes to glycopeptides on clinical outcomes in patients with a bloodstream infection (BSI) through a prospective, multicenter, observational study.

Methods: A total of 509 patients with an EFM BSI from eight sentinel hospitals in South Korea during a two-year period were enrolled in this study. Risk factors of the hosts and causative EFM isolates were assessed to determine associations with the 30-day mortality of EFM BSI patients via multivariable logistic regression analyses.

Results: The vanA gene was detected in 35.2% (179/509) of EFM isolates; 131 EFM isolates exhibited typical VanA phenotypes (group vanA-VanA), while the remaining 48 EFM isolates exhibited atypical phenotypes (group vanA-Atypical), including VanD (n = 43) and vancomycin-variable phenotypes (n = 5). A multivariable logistic regression indicated that vanA-positivity of causative pathogens was independently associated with the increased 30-day mortality rate in the patients with an EFM BSI; however, there was no significant difference in the survival rates between the patients of the vanA-VanA and vanA-Atypical groups (log-rank test, P = 0.904).

Conclusions: A high 30-day mortality rate was observed in patients with vanA-positive EFM BSIs, and vanA-positivity of causative EFM was an independent risk factor for early mortality irrespective of the susceptibility phenotypes to glycopeptides; thus, intensified antimicrobial stewardship is needed to improve clinical outcome of patients with vanA-positive EFM BSI.




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In vitro and in vivo antibiotic capacity of two host defence peptides [Mechanisms of Action]

Two non-amidated host defence peptides named Pin2[G] and FA1 were evaluated against three types of pathogenic bacteria; two isolated from diabetic foot ulcer patients, Staphylococcus aureus UPD13 and Pseudomonas aeruginosa UPD3, and another from a commercial collection, Salmonella enterica serovar Typhimurium (ATCC 14028). In vitro experiments showed that the antimicrobial performance of the synthetic peptides, Pin2[G] and FA1, was modest, although FA1 was more effective than Pin2[G]. In contrast Pin2[G] had superior in vivo anti-infective activity to FA1 in rabbit wound infections by the diabetic foot ulcer pathogens S. aureus UPD13 and P. aeruginosa UPD3. Indeed, Pin2[G] reduced bacterial colony counts of both S. aureus UPD13 and P. aeruginosa UPD3 by >100,000-fold after 48-72 h on skin wounds of infected rabbits, while in similar infected wounds, FA1 had no major effects at 72-96 h of treatment. Ceftriaxone was equally effective vs. Pseudomonas but less effective vs. S. aureus infections. Additionally, the two peptides were evaluated in mice against intragastrically inoculated S. enterica ser. Typhimurium (ATCC 14028). Only Pin2[G], at 0.56 mg/kg, was effective in reducing systemic (liver) infection by >67-fold, equivalent to the effect of treatment with levofloxacin. Pin2[G] showed superior immunomodulatory activity in increasing chemokine production by a human bronchial cell line and suppressing poly(IC)-induced pro-inflammatory IL6 production. These data showed that the in vitro antimicrobial activity of these peptides was not correlated with their in vivo anti-infective activity, and suggest that other factors such as immunomodulatory activity were more important.




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Optimal dose or optimal exposure? Consideration for linezolid in tuberculosis treatment [Letters]

Exploring different ways of minimising linezolid toxicity without compromising efficacy is a major quest in the treatment of drug resistant tuberculosis (TB)....




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Clinically relevant epithelial lining fluid concentrations of meropenem with ciprofloxacin provide synergistic killing and resistance suppression of hypermutable Pseudomonas aeruginosa in a dynamic biofilm model [Pharmacology]

Treatment of exacerbations of chronic Pseudomonas aeruginosa infections in patients with cystic fibrosis (CF) is highly challenging due to hypermutability, biofilm formation and an increased risk of resistance emergence. We evaluated the impact of ciprofloxacin and meropenem as monotherapy and in combination in the dynamic in vitro CDC biofilm reactor (CBR). Two hypermutable P. aeruginosa strains, PAOmutS (MICciprofloxacin 0.25 mg/L, MICmeropenem 2 mg/L) and CW44 (MICciprofloxacin 0.5 mg/L, MICmeropenem 4 mg/L), were investigated for 120h. Concentration-time profiles achievable in epithelial lining fluid (ELF) following FDA-approved doses were simulated in the CBR. Treatments were ciprofloxacin 0.4g every 8h as 1h-infusions (80% ELF penetration), meropenem 6 g/day as continuous infusion (CI; 30% and 60% ELF penetration) and their combinations. Counts of total and less-susceptible planktonic and biofilm bacteria and MICs were determined. Antibiotic concentrations were quantified by UHPLC-PDA. For both strains, all monotherapies failed with substantial regrowth and resistance of planktonic (≥8log10 CFU/mL) and biofilm (>8log10 CFU/cm2) bacteria at 120h (MICciprofloxacin up to 8 mg/L, MICmeropenem up to 64 mg/L). Both combination treatments demonstrated synergistic bacterial killing of planktonic and biofilm bacteria of both strains from ~48h onwards and suppressed regrowth to ≤4log10 CFU/mL and ≤6log10 CFU/cm2 at 120h. Overall, both combination treatments suppressed amplification of resistance of planktonic bacteria for both strains, and biofilm bacteria for CW44. The combination with meropenem at 60% ELF penetration also suppressed amplification of resistance of biofilm bacteria for PAOmutS. Thus, combination treatment demonstrated synergistic bacterial killing and resistance suppression against difficult-to-treat hypermutable P. aeruginosa strains.




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Reply to Kim et al., "Optimal Dose or Optimal Exposure? Consideration for Linezolid in Tuberculosis Treatment" [Author Reply]

We thank Kim and colleagues for their interest in our study....




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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.




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Comparative Genomic Analysis of Third Generation Cephalosporin-Resistant Escherichia coli Harboring blaCMY-2-Positive IncI1 group, IncB/O/K/Z, and IncC Plasmids Isolated from Healthy Broilers in Japan. [Epidemiology and Surveillance]

The off-label use of third generation cephalosporin (3GC) during in ovo vaccination or vaccination of newly hatched chicks, was a common practice worldwide. CMY-2-producing Escherichia coli have been disseminated among broiler production. The objectives of this study were to determine the epidemiological linkage of blaCMY-2-positive plasmids among broilers both within and outside Japan because grandparent stock and parent stock were imported in Japan. We examined the whole genome sequences of 132 3GC-resistant E. coli isolates collected from healthy broilers during 2002-2014. The predominant 3GC-resistance gene was blaCMY-2, which was detected in the plasmids of 87 (65.9%) isolates. The main plasmid replicon types were IncI1-I (n=21; 24.1%), IncI (n=12; 13.8%), IncB/O/K/Z (n=28; 32.2%), and IncC (n=22; 25.3%). Those plasmids were subjected to gene clustering and network analyses and plasmid multi-locus sequence typing (pMLST). The chromosomal DNA of isolates was subjected to MLST and single nucleotide variant (SNV)-based phylogenetic analysis.

MLST and SNV-based phylogenetic analysis revealed high diversity of E. coli isolates. ST429 harboring blaCMY-2-positive IncB/O/K/Z was closely related to isolates from broiler in Germany harboring blaCMY-2-positive IncB/O/K/Z. pST55-IncI and pST12-IncI1-I and pST3-IncC were prevalent in western Japan. pST12-IncI1-I and pST3-IncC were closely related to those detected in E. coli isolates from chicken in American continent, whereas 26 IncB/O/K/Z were related to those in Europe. These data will be useful to reveal the whole picture of transmission of CMY-2-producing bacteria in and out of Japan.




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Google Photos Videos Were Shared With Strangers

Google's Takeout service was designed to let people download their data, but accidentally sent videos from Google Photos accounts to strangers.




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RHSU Classic: How Education Philanthropy Can Accidentally Promote Groupthink and Bandwagonism

In number 10 in our countdown, I tried to offer a few thoughts to funders as they embraced new agendas and looked to avoid repeating yesterday's missteps.




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Champions League Fantasy: Inside info

Who takes the penalties? Who can't you afford to ignore? And who are the bargain signings that could make all the difference?




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Penn State Health selects president for its new Hampden Medical Center

Penn State Health has appointed Don McKenna as president of Penn State Health Hampden Medical Center.




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New guide curates COVID-19 related resources for researchers

Penn State University Libraries has developed a curated guide to COVID-19 related resources for researchers, including ongoing research at Penn State.




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Transgender Adolescent Suicide Behavior

Russell B. Toomey
Oct 1, 2018; 142:e20174218-e20174218
ARTICLES




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Mental Health of Transgender Children Who Are Supported in Their Identities

Kristina R. Olson
Mar 1, 2016; 137:e20153223-e20153223
ARTICLES




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Bone Age: A Handy Tool for Pediatric Providers

Ana L. Creo
Dec 1, 2017; 140:e20171486-e20171486
STATE-OF-THE-ART REVIEW ARTICLES




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Epidemiology of COVID-19 Among Children in China

Yuanyuan Dong
Apr 8, 2020; 0:peds.2020-0702v2-e20200702
ARTICLES




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Fin24.com | 3 'practicalities' to consider before investing in property in Africa – expert

Africa can be a challenging place to do business and property investment is not exempt from some, often unique, challenges, says a Nedbank expert.




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Futsal EURO qualifying main round: full guide

Seven of the 12 places at UEFA Futsal EURO 2018 in Slovenia will be decided when the main round is played between Saturday and Tuesday, with Spain beginning their title defence.




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Futsal rules: a quick guide

The laws of futsal are similar to those of football but with some important differences: let us talk you through the rolling substitutions, accumulated fouls, double penalties and four-second count.




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New Virtual Idea TestLab application deadline is May 15

Happy Valley LaunchBox powered by PNC Bank is accepting applications through May 15 for its Idea TestLab that will now be hosted virtually in June. Open to the community, the four-week Idea TestLab program is designed to help teams evaluate the viability of their business ideas by coaching them through a proven method of customer discovery and problem analysis.




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Video-Based Teacher Collaboration Helps Teachers Find the 'Story of Science'

After a successful pilot, a professional development program is looking to expand its lesson-study approach to rural teachers.




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Clinical Practice Guideline: Nosebleed (Epistaxis)




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UEFA Futsal Cup elite round guide

The UEFA Futsal Cup elite round runs from Wednesday to Sunday, with holders Inter FS and former champions Kairat Almaty and Barcelona among those chasing four available finals spots.




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Lenovo IdeaCentre 510A

Lenovo's IdeaCentre 510A is an unassuming budget desktop in every sense. It'll perform basic tasks without hurting your wallet, but some alternatives do it better at this price point.




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Special Ed. Administrators Press Congress for IDEA Waivers During Pandemic

The requests put the nation's special education administrators in conflict with disability rights advocates who fear waivers will place millions of special education students at risk.




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Sixth resident dies from Covid-19 at Skye Home Farm care home where more than 50 have tested positive

A sixth resident has died from coronavirus in a care home on Skye.




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Three Questions to Guide Your Evaluation of Educational Research

To better understand educational research, start by asking "who?" Who wrote the study; who published it; and who did the authors intend as their audience?




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Teachers of Students With Behavior Problems Want Help Finding Evidence-Based Tools

A survey of educators around the country found that many reported looking up interventions on their own, when they really wanted more formal training, a survey found.




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The Side Effects of Education: Research and Practice

If researchers hope to identify programs that will prepare students for the future, then they cannot continue to measure innovation based on the ideas from the past.




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Video showcases Penn State Berks’ impact on community

Watch Penn State Berks’ new video titled “One Community Impacting Many,” which showcases the depth and breadth of the college’s positive effects on the surrounding region.




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Are Vouchers Hurting or Helping Education? (Video)

Indiana has one of the largest voucher programs in the country, with over 34,000 students receiving tax dollars to pay for private schools. With the Trump administration favoring school choice, many wonder if vouchers help or hurt education.




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Worldwide Timing of Growth Faltering: Revisiting Implications for Interventions

Cesar Gomes Victora
Mar 1, 2010; 125:e473-e480
ARTICLES




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Language of Early- and Later-identified Children With Hearing Loss

Christine Yoshinaga-Itano
Nov 1, 1998; 102:1161-1171
ARTICLES




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An Epidemiologic Profile of Children With Special Health Care Needs

Paul W. Newacheck
Jul 1, 1998; 102:117-123
ARTICLES




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U19 ambassador Mkhitaryan's Armenian pride

Armenia's most famous footballing son, Henrikh Mkhitaryan is the U19 EURO ambassador and looks back at his own youth career.




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Canon CanoScan LiDE 400

The entry-level Canon CanoScan LiDE 400 is a software-rich flatbed photo scanner that also handles text documents with ease.