Antimicrobial resistant Gram-positive cocci in pregnant mothers with aerobic vaginitis

The vaginal microbiota of a healthy asymptomatic woman consists of an extensive diversity of anaerobic and aerobic bacterial genera and species dominated by the microaerophilic genus Lactobacillus , known to inhibit the growth of potentially pathogenic non-acid tolerant microorganisms. An imbalance of species within this biofilm may result in endogenous opportunistic infections such as aerobic vaginitis (AV) caused by S. agalactiae and E. faecalis, which have been implicated in neonatal and obstetric sepsis. The prevalence and antimicrobial susceptibility of E. faecalis and S. agalactiae in pregnant women with AV in the Western Cape, South Africa was determined using standard microbiological culture methods and the Sensititre TREK system. AV was detected in 26.13% of the 199 tested pregnant women, with S. agalactiae and E. faecalis isolated from 32 and 20 mothers respectively. S. agalactiae and E. faecalis showed resistance to 12 of the 17 antibiotics tested, including those recommended for prophylaxis according to the CDC guidelines. The resistance of S. agalactiae and E. faecalis to commonly administered antimicrobials highlights the need for alternative treatment regimens for AV during pregnancy to reduce the risk of AV-associated negative pregnancy outcomes.National Research Foundation of South Afric

Drug susceptibility profiles of Candida species isolated from the oral mucosa of HIV-positive West African patients using the TREK Sensititre system

Poster presented at ASM2013, 113th General Meeting, American Society of Microbiology, 18-21 May, Denver, ColoradoBACKGROUND: Candida infections are a common cause of death in immunocompromised patients. The prevalence and anti-mycotic drug susceptibility profiles of Candida species from Cameroon in Africa are unavailable. This study was prompted by an increasing incidence of treatment failure. Drug susceptibility profiles, necessary to improve treatment outcomes, is particularly important in countries where the sale of antimicrobials and antifungals is uncontrolled and resistance may emerge due to the indiscriminate use. OBJECTIVE: The goal of this study was to characterize and determine drug susceptibility of oral Candida species in Cameroonian patients with HIV/AIDS. MATERIALS AND METHODS: Candida species were isolated from the oral cavity of 126 HIV-positive patients attending a local HIV/AIDS clinic in the Cameroon. Drug susceptibility to azoles and echinocandins was determined using the commercial TREK Sensititre® YeastOne™ platform that provides the minimal inhibitory concentration of amphotericin B, 5-flucytosine, anidulafungin, caspofungin, micafungin, fluconazole, itraconazole, posaconazole, and voriconazole. RESULTS: Ninety two isolates identified were Candida albicans. Remaining isolates were C. glabrata (24), C. tropicalis (4), C. krusei (3), C. parapsilopsis/lusitanreae/keyfr (2), and one isolate was C. dubliniensis. More than 50% of C. albicans isolated were resistant to azoles but 115 Candida species (87%) were susceptible to amphotericin B. Twenty one of the twenty four C.glabrata identified (88%) were resistant to micafungin. The majority of Cameroonian Candida species were sensitive to flucytosine (5-FC) (95%) and echinocandins (79%). CONCLUSIONS: The report of azole resistance in all Candida species isolated from immunocompromised patients in Cameroon is a new and important observation. We found the approach using a broad screening platform an effective means to obtain data rapidly. We propose confirmation of these data and regional surveillance of Candida species in other areas in Cameroon and surrounding countries to develop an effective public health management and treatment strategy

HPLC-MS identification and expression of Candida drug-resistance proteins from African HIV-infected patients

The objective of this study was to elucidate the proteomic mechanisms of drug resistance in HIV-infected African patients. Cell membrane fractions from forty oral Candida isolates isolated from African HIV-positive patients were analysed using HPLC-MS with the aim of identifying proteins associated with their pathogenicity and drug resistance. Heat shock proteins that mediate the fungicidal activity of salivary peptides were found in all tested Candida fractions, with pH-responsive proteins associated with increased pathogenicity only being present in the three most commonly isolated species. ABC multidrug transporter efflux pumps and estrogen binding proteins were only found in C. albicans fractions, while ergosterol biosynthesis proteins were identified in four species. The combination of various adherence, invasion, upregulation and efflux pump mechanisms appear to be instrumental for the Candida host colonization and drug resistance emergence in HIV-infected individuals.This material is based upon work partially supported financially by the National Research Foundation of South Africa [Grant number TTK2008052700013]

Stelleninhaber geht – Wissen bleibt!

In Deutschland nimmt der Anteil älterer Arbeitnehmerinnen und Arbeitnehmer tendenziell zu. Deshalb muss sich die Bibliotheksleitung verstärkt auf das altersbedingte Ausscheiden älterer Arbeitnehmer einstellen. Eine langjährige Fachkraft verfügt über spezielles Erfahrungswissen im direkten Aufgabenfeld. Die Bibliotheksleitung muss den Transfer allen relevanten Wissens, dazu gehört das Erfahrungswissen, vom Stelleninhaber auf seinen Nachfolger ermöglichen und unterstützen. Am Beispiel der Universitätsbibliothek der Bergakademie Freiberg wird untersucht, wie das Wissensmanagement im Rahmen eines Stellenwechsels derzeit geregelt ist. Das geschieht mit Hilfe von Tiefeninterviews in verschiedenen Abteilungen. Die Auswertung der Interviews bildet die Basis für ein Konzept für das Wissensmanagement beim Stellenwechsel an der UB Freiberg. Das Konzept benennt u. a. Maßnahmen zur Identifikation des stellenbezogenen Wissens, Maßnahmen zur Dokumentation des relevanten Wissens und Instrumente zur Wissensweitergabe beim Stellenwechsel

Phylogeny and Diversification Patterns among Vesicomyid Bivalves

Vesicomyid bivalves are among the most abundant and diverse symbiotic taxa in chemosynthetic-based ecosystems: more than 100 different vesicomyid species have been described so far. In the present study, we investigated the phylogenetic positioning of recently described vesicomyid species from the Gulf of Guinea and their western Atlantic and Pacific counterparts using mitochondrial DNA sequence data. The maximum-likelihood (ML) tree provided limited support for the recent taxonomic revision of vesicomyids based on morphological criteria; nevertheless, most of the newly sequenced specimens did not cluster with their morphological conspecifics. Moreover, the observed lack of geographic clustering suggests the occurrence of independent radiations followed by worldwide dispersal. Ancestral character state reconstruction showed a significant correlation between the characters “depth” and “habitat” and the reconstructed ML phylogeny suggesting possible recurrent events of ‘stepwise speciation’ from shallow to deep waters in different ocean basins. This is consistent with genus or species bathymetric segregation observed from recent taxonomic studies. Altogether, our results highlight the need for ongoing re-evaluation of the morphological characters used to identify vesicomyid bivalves

Games of Incomplete Information and Myopic Equilibria

A new concept of an equilibrium in games is introduced that solves an open question posed by A. Neyman

Role of CCL3L1-CCR5 Genotypes in the Epidemic Spread of HIV-1 and Evaluation of Vaccine Efficacy

Polymorphisms in CCR5, the major coreceptor for HIV, and CCL3L1, a potent CCR5 ligand and HIV-suppressive chemokine, are determinants of HIV-AIDS susceptibility. Here, we mathematically modeled the potential impact of these genetic factors on the epidemic spread of HIV, as well as on its prevention.Ro, the basic reproductive number, is a fundamental concept in explaining the emergence and persistence of epidemics. By modeling sexual transmission among HIV+/HIV- partner pairs, we find that Ro estimates, and concordantly, the temporal and spatial patterns of HIV outgrowth are highly dependent on the infecting partners' CCL3L1-CCR5 genotype. Ro was least and highest when the infected partner possessed protective and detrimental CCL3L1-CCR5 genotypes, respectively. The modeling data indicate that in populations such as Pygmies with a high CCL3L1 gene dose and protective CCR5 genotypes, the spread of HIV might be minimal. Additionally, Pc, the critical vaccination proportion, an estimate of the fraction of the population that must be vaccinated successfully to eradicate an epidemic was <1 only when the infected partner had a protective CCL3L1-CCR5 genotype. Since in practice Pc cannot be >1, to prevent epidemic spread, population groups defined by specific CCL3L1-CCR5 genotypes might require repeated vaccination, or as our models suggest, a vaccine with an efficacy of >70%. Further, failure to account for CCL3L1-CCR5-based genetic risk might confound estimates of vaccine efficacy. For example, in a modeled trial of 500 subjects, misallocation of CCL3L1-CCR5 genotype of only 25 (5%) subjects between placebo and vaccine arms results in a relative error of approximately 12% from the true vaccine efficacy.CCL3L1-CCR5 genotypes may impact on the dynamics of the HIV epidemic and, consequently, the observed heterogeneous global distribution of HIV infection. As Ro is lowest when the infecting partner has beneficial CCL3L1-CCR5 genotypes, we infer that therapeutic vaccines directed towards reducing the infectivity of the host may play a role in halting epidemic spread. Further, CCL3L1-CCR5 genotype may provide critical guidance for optimizing the design and evaluation of HIV-1 vaccine trials and prevention programs