96 research outputs found

    Social-Cultural Environment and Performance of Donor Funded Health Projects in Kenya

    Get PDF
    This study provides an empirical investigation on the effect of the social-cultural environment; local community literacy levels, support from local communities, language, and corruption levels on the performance of donor-funded health projects in Kenya. Empirical evidence indicatesthat most donor-funded health projects in Kenya experience time and cost overruns as well as quality issues. This study investigated a population of 69 donor-funded health projects that were initiated between 2008 and 2018 and were ongoing during the study period. A census study was conducted to ensure efficiency, representativeness, reliability, and flexibility since the population was small. The study adopted explanatory and descriptive research designs. Regression results indicated that language, support from the local communities, and the level of literacy in the local communities had positive relationships with the performance of donor-funded health projects in Kenya with coefficients of 0.021, 0.045, and 0.042 respectively. These factors were significant at a 5 percent significance level with p-values of 0.018, 0.019, and 0.047 respectively. Corruption levels had a negative relationship with the performance of donor-funded health projects in Kenya with a coefficient of - 0.031 that was significant at a 5 percent significance level with a p-value of 0.013. The study recommends that the government develops policies and frameworks that will help projects to minimize the negative effects of the social-cultural environment and enhance the positive effects, and that all decision-makers and other donor-funded health project stakeholders devise policies and strategies for controlling the effect of the social-cultural environment on the donor-funded health projects

    Deciphering the distance to antibiotic resistance for the pneumococcus using genome sequencing data

    Get PDF
    Advances in genome sequencing technologies and genome-wide association studies (GWAS) have provided unprecedented insights into the molecular basis of microbial phenotypes and enabled the identification of the underlying genetic variants in real populations. However, utilization of genome sequencing in clinical phenotyping of bacteria is challenging due to the lack of reliable and accurate approaches. Here, we report a method for predicting microbial resistance patterns using genome sequencing data. We analyzed whole genome sequences of 1,680 Streptococcus pneumoniae isolates from four independent populations using GWAS and identified probable hotspots of genetic variation which correlate with phenotypes of resistance to essential classes of antibiotics. With the premise that accumulation of putative resistance-conferring SNPs, potentially in combination with specific resistance genes, precedes full resistance, we retrogressively surveyed the hotspot loci and quantified the number of SNPs and/or genes, which if accumulated would confer full resistance to an otherwise susceptible strain. We name this approach the € distance to resistance'. It can be used to identify the creep towards complete antibiotics resistance in bacteria using genome sequencing. This approach serves as a basis for the development of future sequencing-based methods for predicting resistance profiles of bacterial strains in hospital microbiology and public health settings

    Characterization of the Theileria parva sporozoite proteome

    Get PDF
    East Coast fever is a lymphoproliferative disease caused by the tick-borne protozoan parasite Theileria parva. The sporozoite stage of this parasite, harboured and released from the salivary glands of the tick Rhipicephalus appendiculatus during feeding, invades and establishes infection in bovine lymphocytes. Blocking this initial stage of invasion presents a promising vaccine strategy for control of East Coast fever and can in part be achieved by targeting the major sporozoite surface protein p67. To support research on the biology of T. parva and the identification of additional candidate vaccine antigens, we report on the sporozoite proteome as defined by LC–MS/MS analysis. In total, 4780 proteins were identified in an enriched preparation of sporozoites. Of these, 2007 were identified as T. parva proteins, representing close to 50% of the total predicted parasite proteome. The remaining 2773 proteins were derived from the tick vector. The identified sporozoite proteins include a set of known T. parva antigens targeted by antibodies and cytotoxic T cells from cattle that are immune to East Coast fever. We also identified proteins predicted to be orthologs of Plasmodium falciparum sporozoite surface molecules and invasion organelle proteins, and proteins that may contribute to the phenomenon of bovine lymphocyte transformation. Overall, these data establish a protein expression profile of T. parva sporozoites as an important starting point for further study of a parasitic species which has considerable agricultural impact

    Opportunistic bacteria confer the ability to ferment prebiotic starch in the adult cystic fibrosis gut

    Get PDF
    Chronic disruption of the intestinal microbiota in adult cystic fibrosis (CF) patients is associated with local and systemic inflammation, and has been linked to the risk of serious comorbidities. Supplementation with high amylose maize starch (HAMS) might provide clinical benefit by promoting commensal bacteria and the biosynthesis of immunomodulatory metabolites. However, whether the disrupted CF gut microbiota has the capacity to utilise these substrates is not known. We combined metagenomic sequencing, in vitro fermentation, amplicon sequencing, and metabolomics to define the characteristics of the faecal microbiota in adult CF patients and assess HAMS fermentation capacity. Compared to healthy controls, the faecal metagenome of adult CF patients had reduced bacterial diversity and prevalence of commensal fermentative clades. In vitro fermentation models seeded with CF faecal slurries exhibited reduced acetate levels compared to healthy control reactions, but comparable levels of butyrate and propionate. While the commensal genus Faecalibacterium was strongly associated with short chain fatty acid (SCFA) production by healthy microbiota, it was displaced in this role by Clostridium sensu stricto 1 in the microbiota of CF patients. A subset of CF reactions exhibited enterococcal overgrowth, resulting in lactate accumulation and reduced SCFA biosynthesis. The addition of healthy microbiota to CF faecal slurries failed to displace predominant CF taxa, or substantially influence metabolite biosynthesis. Despite significant microbiota disruption, the adult CF gut microbiota retains the capacity to exploit HAMS. Our findings highlight the potential for taxa associated with the altered CF gut microbiotato mediate prebiotic effects in microbial systems subject to ongoing perturbation, irrespective of the depletion of common commensal clades

    From microbial gene essentiality to novel antimicrobial drug targets

    Get PDF
    Background: Bacterial respiratory tract infections, mainly caused by Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis are among the leading causes of global mortality and morbidity. Increased resistance of these pathogens to existing antibiotics necessitates the search for novel targets to develop potent antimicrobials. Result: Here, we report a proof of concept study for the reliable identification of potential drug targets in these human respiratory pathogens by combining high-density transposon mutagenesis, high-throughput sequencing, and integrative genomics. Approximately 20% of all genes in these three species were essential for growth and viability, including 128 essential and conserved genes, part of 47 metabolic pathways. By comparing these essential genes to the human genome, and a database of genes from commensal human gut microbiota, we identified and excluded potential drug targets in respiratory tract pathogens that will have off-target effects in the host, or disrupt the natural host microbiota. We propose 249 potential drug targets, 67 of which are targets for 75 FDA-approved antimicrobials and 35 other researched small molecule inhibitors. Two out of four selected novel targets were experimentally validated, proofing the concept. Conclusion: Here we have pioneered an attempt in systematically combining the power of high-density transposon mutagenesis, high-throughput sequencing, and integrative genomics to discover potential drug targets at genome-scale. By circumventing the time-consuming and expensive laboratory screens traditionally used to select potential drug targets, our approach provides an attractive alternative that could accelerate the much needed discovery of novel antimicrobials

    Intestinal microbiology shapes population health impacts of diet and lifestyle risk exposures in torres strait islander communities

    Get PDF
    Poor diet and lifestyle exposures are implicated in substantial global increases in non-communicable disease burden in low-income, remote, and Indigenous communities. This observational study investigated the contribution of the fecal microbiome to influence host physiology in two Indigenous communities in the Torres Strait Islands: Mer, a remote island where a traditional diet predominates, and Waiben a more accessible island with greater access to takeaway food and alcohol. Counterintuitively, disease markers were more pronounced in Mer residents. However, island-specific differences in disease risk were explained, in part, by microbiome traits. The absence of Alistipes onderdonkii, for example, significantly (p=0.014) moderated island-specific patterns of systolic blood pressure in multivariate-adjusted models. We also report mediatory relationships between traits of the fecal metagenome, disease markers, and risk exposures. Understanding how intestinal microbiome traits influence response to disease risk exposures is critical for the development of strategies that mitigate the growing burden of cardiometabolic disease in these communities

    Phage-derived protein induces increased platelet activation and is associated with mortality in patients with invasive pneumococcal disease

    Get PDF
    To improve our understanding about the severity of invasive pneumococcal disease (IPD), we investigated the association between the genotype of Streptococcus pneumoniae and disease outcomes for 349 bacteremic patients. A pneumococcal genome-wide association study (GWAS) demonstrated a strong correlation between 30-day mortality and the presence of the phage-derived gene pblB, encoding a platelet-binding protein whose effects on platelet activation were previously unknown. Platelets are increasingly recognized as key players of the innate immune system, and in sepsis, excessive platelet activation contributes to microvascular obstruction, tissue hypoperfusion, and finally multiorgan failure, leading to mortality. Our in vitro studies revealed that pblB expression was induced by fluoroquinolones but not by the beta-lactam antibiotic penicillin G. Subsequently, we determined pblB induction and platelet activation by incubating whole blood with the wild type or a pblB knockout mutant in the presence or absence of antibiotics commonly administered to our patient cohort. pblB-dependent enhancement of platelet activation, as measured by increased expression of the ɑ-granule protein P-selectin, the binding of fibrinogen to the activated ɑ IIbβ3 receptor, and the formation of platelet-monocyte complex occurred irrespective of antibiotic exposure. In conclusion, the presence of pblB on the pneumococcal chromosome potentially leads to increased mortality in patients with an invasive S. pneumoniae infection, which may be explained by enhanced platelet activation. This study highlights the clinical utility of a bacterial GWAS, followed by functional characterization, to identify bacterial factors involved in disease severity. IMPORTANCE The exact mechanisms causing mortality in invasive pneumococcal disease (IPD) patients are not completely understood. We examined 349 patients with IPD and found in a bacterial genome-wide association study (GWAS) that the presence of the phage-derived gene pblB was associated with mortality in the first 30 days after hospitalization. Although pblB has been extensively studied in Streptococcus mitis, its consequence for the interaction between platelets and Streptococcus pneumoniae is largely unknown. Platelets are important in immunity and inflammation, and excessive platelet activation contributes to microvascular obstruction and multiorgan failure, leading to mortality. We therefore developed this study to assess whether the expression of pblB might increase the risk of death for IPD patients through its effect on enhanced platelet activation. This study also shows the value of integrating extensive bacterial genomics and clinical data in predicting and understanding pathogen virulence, which in turn will help to improve prognosis and therapy
    • …
    corecore