colonizes hosts by interacting with Blood Group Antigens (BgAgs) on the surface of gastrointestinal epithelia. Genetic variations in BgAg expression affects host susceptibility to
. Here, we show ...that the essential major outer membrane protein (MOMP) of
NCTC11168 binds to the Lewis b (Le
) antigen on the gastrointestinal epithelia of host tissues and this interaction can be competitively inhibited by ferric quinate (QPLEX), a ferric chelate structurally similar to bacterial siderophores. We provide evidence that QPLEX competitively inhibits the MOMP-Le
interaction. Furthermore, we demonstrate that QPLEX can be used as a feed additive in broiler farming to significantly reduce
colonization. Our results indicate that QPLEX can be a viable alternative to the preventative use of antibiotics in broiler farming to combat
infections.
COVID-19 in Africa: an ovarian victory? Dufailu, Osman A; Afriyie-Asante, Afrakoma; Gyan, Bernard ...
Journal of ovarian research,
05/2021, Letnik:
14, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Coronavirus disease 2019 (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) mainly attacks the respiratory system and is characterized by pneumonia, cytokine storm, ...coagulation disorders and severe immune downregulation. Although public health experts predicted worst outcomes in Africa, the incidence, hospitalization and mortality rates have been lower in Africa compared to other continents. Interestingly, lower incidence and mortality rates have been observed in women from Africa compared to their cohorts from other continents. Also, in the US non-Hispanic Black females have lower COVID-19 and death rates compared to their white counterparts. It's unclear why this significant difference exists; however, the ovarian function, genetics and immunological statuses could play a major role. Women of African descent have elevated levels of estrogen compared with Caucasians hence we anticipate that estrogen might offer some protection against the SARS-CoV-2 infections. The racial differences in lifestyle, age and inaccessibility to contraceptive usage might also play a role. Here, we provide insight on how the high levels of estrogen in African women might contribute to the lower cases and fatalities in Africa. Specifically, estrogen might offer protection against COVID-19 by suppressing hyper-production of cytokines, promoting anti-inflammatory cytokines, stimulating antibody production and suppressing endoplasmic reticulum (ER) stress. This will as well provide useful information on how future pandemics could be managed using Africa as a case study.
Cysticercosis caused by the larval stages of Taenia hydatigena has a significant global impact on livestock production, particularly of goats and sheep. Despite this, global data on prevalence and ...genetic variance of this parasite are still scarce. In Ghana, as in most African countries, numerous anecdotal observations agree that it is widespread and frequent. To obtain baseline data, we screened 251 goats and 248 sheep in northern Ghana (Upper East Region) for T. hydatigena metacestode and molecularly characterized the isolates using the mtDNA cox1 gene sequence. Prevalence was 58.57% in goats and 60.48% in sheep, confirming the abundance of this parasite in the region. Gene sequences revealed high diversity (π 0.00346, hd 0.809) and significant negative Tajima D and Fu's Fs values, a characteristic of a population experiencing an expansion after a recent bottleneck. This is the first account of the genetic structure of T. hydatigena in Ghana, intended as a basis for subsequent studies in the region.
•Prevalence of Taenia hydatigena in goat and sheep from Ghana's Upper East Region is above 50%.•Taenia hydatigena populations exhibit high genetic variance and expanding demography.•Taenia hydatigena haplotypes in northern Ghana are in a star-like distribution.
Neisseria meningitidis is normally a human nasopharyngeal commensal but is also capable of causing life-threatening sepsis and meningitis. N. meningitidis secretes several virulence-associated ...proteins including Neisserial autotransporter lipoprotein (NalP), an immunogenic, type Va autotransporter harboring an S8-family serine endopeptidase domain. NalP has been previously characterized as a cell-surface maturation protease which processes other virulence-associated meningococcal surface proteins, and as a factor contributing to the survival of meningococci in human serum due to its ability to cleave complement factor C3. Here, recombinant NalP (rNalP) fragments were purified and used to investigate the interaction of NalP with host cells. Flow cytometry and confocal microscopy demonstrated binding and uptake of rNalP into different human cell types. High-resolution microscopy confirmed that internalized rNalP predominantly localized to the perinuclear region of cells. Abolition of rNalP protease activity using site-directed mutagenesis did not influence uptake or sub-cellular localization, but inactive rNalP (rNalPS426A) was unable to induce an increase in human brain microvascular endothelial cell metabolic activity provoked by proteolytically-active rNalP. Our data suggests a more complex and multifaceted role for NalP in meningococcal pathogenesis than was previously understood which includes novel intra-host cell functions.
•Recombinant NalP is internalized by a variety of human cell types.•Internalized NalP is localized predominantly to the perinuclear region of cells.•Exposure to NalP provokes increases in cell metabolic activity.•Effects on cell metabolic activity are dependent on NalP proteolytic activity.
Summary
Neisseria meningitidis, a major cause of bacterial meningitis and septicaemia, secretes multiple virulence factors, including the adhesion and penetration protein (App) and meningococcal ...serine protease A (MspA). Both are conserved, immunogenic, type Va autotransporters harbouring S6‐family serine endopeptidase domains. Previous work suggested that both could mediate adherence to human cells, but their precise contribution to meningococcal pathogenesis was unclear. Here, we confirm that App and MspA are in vivo virulence factors since human CD46‐expressing transgenic mice infected with meningococcal mutants lacking App, MspA or both had improved survival rates compared with mice infected with wild type. Confocal imaging showed that App and MspA were internalized by human cells and trafficked to the nucleus. Cross‐linking and enzyme‐linked immuno assay (ELISA) confirmed that mannose receptor (MR), transferrin receptor 1 (TfR1) and histones interact with MspA and App. Dendritic cell (DC) uptake could be blocked using mannan and transferrin, the specific physiological ligands for MR and TfR1, whereas in vitro clipping assays confirmed the ability of both proteins to proteolytically cleave the core histone H3. Finally, we show that App and MspA induce a dose‐dependent increase in DC death via caspase‐dependent apoptosis. Our data provide novel insights into the roles of App and MspA in meningococcal infection.
The microbial quality of household water is an important issue in developing countries, especially in Ghana, where many people still depend on unimproved sources of water. The present study ...investigated the prevalence, genetic characteristics, and antimicrobial resistance profile of Escherichia coli from surface water sources. Fifty-two water samples were analyzed by using a spread plate, a biochemical test, and multiplex polymerase chain reactions. E. coli was isolated from each of the 52 water samples. Of these isolates, 75% were noted to possess virulence genes. Approximately 54% of the isolates were characterized as follows: enterotoxigenic E. coli (ETEC, 10.26%), enteropathogenic E. coli (EPEC, 17.95%), verotoxigenic E. coli (VTEC, 23.07%), and enteroinvasive E. coli (EIEC, 2.57%). Eighteen of the fifty-two isolates could not be characterized due to heterogeneity in banding. The disc diffusion method was used to test for antimicrobial susceptibility. The isolates were most resistant to ceftazidime, augmentin, and cefuroxime. Multidrug resistance was recorded in 48.1% of the isolates. In contrast, the isolates were most susceptible to ciprofloxacin (86.5%), nitrofurantoin (84.6%), and ofloxacin (75%). These results revealed a high diversity and widespread of E. coli in northern Ghana. The study provides important data for public health nationwide surveillance of E. coli in surface water across the country.
Honey is often considered a good substitute for sugar. However, concerns about the poor quality of locally produced honey have necessitated the importation of honey to meet the domestic demand in ...spite of Ghana’s good climatic conditions suitable for honey production. Due to the increasing level of demand for honey both locally and internationally, we highlighted here the need for an assessment of the physicochemical, microbiological quality, and antibiotics resistance of microbes isolated from the imported and locally produced honey vis-à-vis international standards. Thirty honey samples which comprise 7 imported and 23 locally produced were randomly sampled from retail outlets consisting of supermarkets, marts, shops, and open markets as well as from production sites within the northern region for physicochemical analysis, microbial analysis, and antibiogram. Results of the physicochemical quality analysis showed that sampled honey (both imported and locally produced) was within acceptable set standards. However, microbial quality was poor as a high incidence of bacterial contamination and resistance was recorded in the study. The High incidence of bacterial contamination and antibiotic resistance recorded in this study gives an indication that all is not well in the honey industry and therefore the need for appropriate measures to avert possible health issues associated with the consumption of honey found within the region.
Rural chicken production in Ghana is predominantly done under the extensive system that exposes birds to parasitic infections. We investigated the prevalence of Ascaridia spp. and Heterakis spp. and ...as a preliminary study characterized the genetic variance of the Ascaridia galli isolates from rural chicken in Kumbungu, Savelugu and Tolon Districts in the Northern Region, Ghana. A total of 86 chickens aged 6–10 weeks were dissected and GIT inspected for nematodes. Nematode were described based on morphological features to be A. galli and H. gallinarum. Additionally, the mitochondrial cox1 gene (475 bp) of Ascaridia isolates was amplified and sequenced. The overall prevalence of nematodes was 47.67%: A. galli 37.21% and H. gallinarum 20.93%. Prevalence values of A. galli in the Kumbungu, Savelugu and Tolon Districts were 25.00%, 36.00%, 56.00%, respectively, and that of H. gallinarum, respectively were 16.67%, 28.00% and 20.00%. A Chi-square test (x2 = 6.0907, p < 0.048) showed an association of A. galli prevalence to the district of origin of birds. From 20 A. galli cox1 sequences analyzed, all sequences were identified as A. galli. Two haplotypes were recorded, namely, GHA1 and GHA2. Haplotype GHA1 was found to have wide distribution globally, whereas GHA2 appear to be novel in the present study. The data shows the importance of A. galli and H. gallinarum infection in rural chicken in northern Ghana and pave way for further epidemiological study of avian nematodes.
•Prevalence of Ascaridia galli in rural chicken in Ghana's Northern Region is above 30%.•Prevalence of Heterakis gallinarum in rural chicken in Ghana's Northern Region is at least 20%.•A. galli population in rural chicken in northern Ghana revealed two haplotypes based on the cox1 gene.•A. galli population in rural chicken exhibit low genetic variance and expanding demography.
Gonorrhoea is a disease associated with humans and caused by
s ability to evolve and evade various treatment regimens can lead to untreatable gonorrhoea. In the absence of a viable vaccine and a ...national database on the antimicrobial resistance (AMR) and molecular characteristics of
and with reliance on a syndromic management regime, continuous national antimicrobial resistance surveillance and molecular characterization of
remain imperative. Only two gonococcal studies have described
molecular characteristics linked to AMR in Ghana.
Secondary
isolates (
=4) were collected from two metropolises in Ghana: Tamale in the northern sector (
=1) and Accra in the southern sector (
=3). The isolates were confirmed and characterized using polymerase chain reaction (PCR) targeting the
B and
B genes, and the disc diffusion method was used to evaluate AMR.
multi-antigen sequence typing (NG-MAST) and porin B (
B) gene sequence analyses were employed to reveal the molecular epidemiology and evolutionary trajectory, respectively.
All four isolates showed resistance to at least four of the tested antibiotics. One isolate showed resistance to all seven antibiotics, i.e. ceftriaxone, azithromycin, ciprofloxacin, tetracycline, erythromycin, togamycin and penicillin. NG-MAST typing revealed isolate S3 (MZ313864) as ST211. The locus of S2 (MZ313863) (transferrin-binding protein B;
B) was identified as
B1844, and its
B locus, as
B6412, with only 4 closely related variants but with 15 nucleotide differences. However, its sequence type does not exist. The
B analysis identified isolate S3 (MZ313864) to be found globally, while S2 (MZ313863) is unique to this study.
Despite the small number of isolates tested, this study recorded multidrug resistance and previously unknown gonococcal variants based on
B gene. Additionally, the molecular typing schemes revealed a disparity between NG-MAST and the National Center for Biotechnology Information (NCBI) platforms. There is a need for continuous gonococcal AMR and molecular surveillance in Ghana to contribute to the global efforts to describe circulating strains and support proper application of the syndromic management regime to gonorrhoea.
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