Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1297202 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The non-typhoidal Salmonella enterica serotype Heidelberg is a major foodborne pathogen primarily transmitted to humans through contaminated poultry products. Current control measures emphasize novel approaches to mitigate Salmonella Heidelberg colonization in poultry and the contamination of poultry products, thereby reducing its transmission to humans. This study highlight that commensal E. coli 47-1826 can potentially be used to control of S. Heidelberg 18-9079 in poultry
2024-09-17 | GSE276976 | GEO
Project description:The emergence and fast global spread of COVID-19 has presented one of the greatest public health challenges in modern times with no proven cure or vaccine. Africa is still early in this epidemic, therefore the extent of disease severity is not yet clear. We used a mathematical model to fit to the observed cases of COVID-19 in South Africa to estimate the basic reproductive number and critical vaccination coverage to control the disease for different hypothetical vaccine efficacy scenarios. We also estimated the percentage reduction in effective contacts due to the social distancing measures implemented. Early model estimates show that COVID-19 outbreak in South Africa had a basic reproductive number of 2.95 (95% credible interval [CrI] 2.83–3.33). A vaccine with 70% efficacy had the capacity to contain COVID-19 outbreak but at very higher vaccination coverage 94.44% (95% Crl 92.44–99.92%) with a vaccine of 100% efficacy requiring 66.10% (95% Crl 64.72–69.95%) coverage. Social distancing measures put in place have so far reduced the number of social contacts by 80.31% (95% Crl 79.76–80.85%). These findings suggest that a highly efficacious vaccine would have been required to contain COVID-19 in South Africa. Therefore, the current social distancing measures to reduce contacts will remain key in controlling the infection in the absence of vaccines and other therapeutics.
2024-09-02 | BIOMD0000000978 | BioModels
Project description:Esophageal squamous cell carcinoma (ESCC) is an aggressive cancer with one of the highest world incidences in the Eastern Cape region of South Africa. Several genome wide studies have been performed on ESCC cohorts from Asian countries, North America, Malawi and other parts of the world but none has been conducted on ESCC tumors from South Africa to date, where the molecular pathology and etiology of this disease remains unclear. We report here tumor associated copy number changes observed in 51 ESCC patients’ samples from the Eastern Cape province of South Africa. We extracted tumor DNA from 51 archived ESCC specimens and interrogated tumor associated DNA copy number changes using Affymetrix® 500K SNP array technology. The Genomic Identification of Significant Targets in Cancer (GISTIC) algorithm was applied to identify significant focal regions of gains and losses. Gains of the top recurrent cancer genes were validated by fluorescence in situ hybridization and their protein expression assessed by immunohistochemistry. Twenty-three significant focal gains were identified across samples. Gains involving the CCND1, MYC, EGFR and JAG1 loci recapitulated those described in studies on Asian and Malawian cohorts. The two most significant gains involved the chromosomal sub-bands 3q28, encompassing the TPRG1 gene and 11q13.3 including the CTTN, PPFIA1and SHANK2 genes. There was no significant homozygous loss and the most recurrent hemizygous deletion involved the B3GAT1 gene on chromosome11q25. Focal gains on 11q13.3 in 37% of cases (19/51), consistently involved CTTN and SHANK2 genes. Twelve of these cases (23,5%), had a broader region of gain that also included the CCND1, FGF19, FGF4 and FGF3 genes. SHANK2 and CTTN are co-amplified in several cancers, these proteins interact functionally together and are involved in cell motility. Immunohistochemistry confirmed both Shank2 (79%) and cortactin (69%) protein overexpression in samples with gains of these genes. In contrast, cyclin D1 (65%) was moderately expressed in samples with CCND1 DNA gain. This study reports copy number changes in a South African ESCC cohort and highlights similarities and differences with cohorts from Asia and Malawi. Our results strongly suggest a role for CTTN and SHANK2 in the pathogenesis of ESCC in South Africa.
2020-04-07 | GSE59105 | GEO
Project description:Background. The bacterial foodborne pathogen Campylobacter jejuni is a common cause of acute gastroenteritis and is also associated with the postinfectious neuropathies, Guillain-Barré and Miller Fisher syndromes. This study described the use of multilocus sequence typing and DNA microarrays to examine the genetic content of a collection of South African C. jejuni strains, recovered from patients with enteritis, Guillain-Barré or Miller Fisher syndromes. Methodology/Principal Findings. The comparative genomic analysis by using multilocus sequence typing and DNA microarrays demonstrated that the South African strains with Penner heat-stable (HS) serotype HS:41 were clearly distinct from the other South African strains. Further analysis of the DNA microarray data demonstrated that the serotype HS:41 strains from South African GBS and enteritis patients are highly similar in gene content. Interestingly, the South African HS:41 strains were distinct in gene content when compared to serotype HS:41 strains from other geographical locations due to the presence of genomic islands, referred to as Campylobacter jejuni integrated elements. Only the genomic integrated element CJIE1, a Campylobacter Mu-like prophage, was present in the South African HS:41 strains whereas absent in the closely-related HS:41 strains from Mexico. A more distantly-related HS:41 strain from Canada possessed both genomic integrated elements CJIE1 and CJIE2. Conclusion/Significance. These findings demonstrated that these C. jejuni integrated elements may contribute to the differentiation of closely-related C. jejuni strains. In addition, the presence of bacteriophage-related genes in CJIE1 may probably contribute to increasing the genomic diversity of these C. jejuni strains. This comparative genomic analysis of the foodborne pathogen C. jejuni provides fundamental information that potentially could lead to improved methods for analyzing the epidemiology of disease outbreaks and their sources. Keywords: comparative genomic indexing analysis
2007-12-19 | GSE9862 | GEO
Project description:Non-typhoidal Salmonella (NTS) are among of the most important food-borne pathogens. Recently, a highly invasive multi-drug resistant S. Typhimurium of a distinct multilocus sequence type (MLST), ST313, has emerged across sub-Saharan Africa as a major cause of lethal bacteraemia in children and immunosuppressed adults. Encounters between dendritic cells (DCs) and invading bacteria determine the course of infection but whether or how ST313 might usurp DC mediated defence has not been reported. Here we utilised fluorescently labelled invasive and non-invasive strains of Salmonella combined with single-cell RNA sequencing to study the transcriptomes of individual infected and bystander DCs. The transcriptomes displayed a repertoire of cell instrinsic and extrinsic innate response states that differed between invasive and non-invasive strains. Gene expression heterogeneity was increased in DCs challenged with invasive Salmonella. DCs exposed but not harbouring invasive Salmonella exhibited a hyper-activated profile that likely facilitates trafficking of infected cells and dissemination of internalised intact bacteria. In contrast, invasive Salmonella containing DCs demonstrate reprogramming of trafficking genes required to avoid autophagic destruction. Furthermore, these cells displayed differential expression of tolerogenic IL10 and MARCH1 enabling CD83 mediated adaptive immune evasion. Altogether our data illustrate pathogen cell-to cell variability directed by a Salmonella invasive strain highlighting potential mechanisms of host adaption with implications for dissemination in vivo.
2018-10-25 | GSE111545 | GEO
Project description:Non-typhoidal Salmonella (NTS) are among of the most important food-borne pathogens. Recently, a highly invasive multi-drug resistant S. Typhimurium of a distinct multilocus sequence type (MLST), ST313, has emerged across sub-Saharan Africa as a major cause of lethal bacteraemia in children and immunosuppressed adults. Encounters between dendritic cells (DCs) and invading bacteria determine the course of infection but whether or how ST313 might usurp DC mediated defence has not been reported. Here we utilised fluorescently labelled invasive and non-invasive strains of Salmonella combined with single-cell RNA sequencing to study the transcriptomes of individual infected and bystander DCs. The transcriptomes displayed a repertoire of cell instrinsic and extrinsic innate response states that differed between invasive and non-invasive strains. Gene expression heterogeneity was increased in DCs challenged with invasive Salmonella. DCs exposed but not harbouring invasive Salmonella exhibited a hyper-activated profile that likely facilitates trafficking of infected cells and dissemination of internalised intact bacteria. In contrast, invasive Salmonella containing DCs demonstrate reprogramming of trafficking genes required to avoid autophagic destruction. Furthermore, these cells displayed differential expression of tolerogenic IL10 and MARCH1 enabling CD83 mediated adaptive immune evasion. Altogether our data illustrate pathogen cell-to cell variability directed by a Salmonella invasive strain highlighting potential mechanisms of host adaption with implications for dissemination in vivo.
2018-10-25 | GSE111543 | GEO
Project description:Salmonella Infantis from United Kingdom and South Africa
| PRJEB62677 | ENA
Project description:Salmonella Heidelberg is currently the 9th common serovar and has more than twice the average incidence of blood infections in Salmonella. A recent Salmonella Heidelberg outbreak in chicken infected 634 people during 2013-2014, with a hospitalization rate of 38% and an invasive illness rate of 15%. While the company’s history suggested longstanding sanitation issues, the strains’ characteristics which may have contributed to the outbreak are unknown. We hypothesized that the outbreak strains of S. Heidelberg might possess enhanced stress tolerance or virulence capabilities. Consequently, we obtained nine food isolates collected during the outbreak investigation and several reference isolates and tested their tolerance to processing stresses, their ability to form biofilms, and their invasiveness in vitro. We further performed RNA-sequencing on three isolates with varying heat tolerance to determine the mechanism behind our isolates’ enhanced heat tolerance. Ultimately, we determined that (i) many Salmonella Heidelberg isolates associated with a foodborne outbreak have enhanced heat resistance (ii) Salmonella Heidelberg outbreak isolates have enhanced biofilm-forming ability under stressful conditions, compared to the reference strain (iii) exposure to heat stress may also increase Salmonella Heidelberg isolates’ antibiotic resistance and virulence capabilities and (iv) Salmonella Heidelberg outbreak-associated isolates are primed to better survive stress and cause illness. This data helps explain the severity and scope of the outbreak these isolates are associated with and can be used to inform regulatory decisions on Salmonella in poultry and to develop assays to screen isolates for stress tolerance and likelihood of causing severe illness.
2018-09-01 | GSE103418 | GEO