Association of virulence plasmid and antibiotic resistance determinants with chromosomal multilocus genotypes in Mexican Salmonella enterica serovar Typhimurium strains

<p>Abstract</p> <p>Background</p> <p>Bacterial genomes are mosaic structures composed of genes present in every strain of the same species (core genome), and genes present in some but not all strains of a species (accessory genome). The aim of this study was to compare the genetic diversity of core and accessory genes of a <it>Salmonella enterica </it>subspecies <it>enterica </it>serovar Typhimurium (Typhimurium) population isolated from food-animal and human sources in four regions of Mexico. Multilocus sequence typing (MLST) and macrorestriction fingerprints by pulsed-field gel electrophoresis (PFGE) were used to address the core genetic variation, and genes involved in pathogenesis and antibiotic resistance were selected to evaluate the accessory genome.</p> <p>Results</p> <p>We found a low genetic diversity for both housekeeping and accessory genes. Sequence type 19 (ST19) was supported as the founder genotype of STs 213, 302 and 429. We found a temporal pattern in which the derived ST213 is replacing the founder ST19 in the four geographic regions analyzed and a geographic trend in the number of resistance determinants. The distribution of the accessory genes was not random among chromosomal genotypes. We detected strong associations among the different accessory genes and the multilocus chromosomal genotypes (STs). First, the <it>Salmonella </it>virulence plasmid (pSTV) was found mostly in ST19 isolates. Second, the plasmid-borne betalactamase <it>cmy-2 </it>was found only in ST213 isolates. Third, the most abundant integron, IP-1 (<it>dfrA12</it>, <it>orfF </it>and <it>aadA2</it>), was found only in ST213 isolates. Fourth, the <it>Salmonella </it>genomic island (SGI1) was found mainly in a subgroup of ST19 isolates carrying pSTV. The mapping of accessory genes and multilocus genotypes on the dendrogram derived from macrorestiction fingerprints allowed the establishment of genetic subgroups within the population.</p> <p>Conclusion</p> <p>Despite the low levels of genetic diversity of core and accessory genes, the non-random distribution of the accessory genes across chromosomal backgrounds allowed us to discover genetic subgroups within the population. This study provides information about the importance of the accessory genome in generating genetic variability within a bacterial population.</p

Does an L-glutamine-containing, Glucose-free, Oral Rehydration Solution Reduce Stool Output and Time to Rehydrate in Children with Acute Diarrhoea? A Double-blind Randomized Clinical Trial

This study assessed whether an oral rehydration solution (ORS) in which glucose is replaced by L-glutamine (L-glutamine ORS) is more effective than the standard glucose-based rehydration solution recommended by the World Health Organization (WHO-ORS) in reducing the stool volume and time to rehydrate in acute diarrhoea. In a double-blind, randomized controlled trial in a Mexican hospital, 147 dehydrated children, aged 1–60 month(s), were assigned either to the WHO-ORS (74 children), or to the L-glutamine ORS (73 children) and followed until successful rehydration. There were no significant differences between the groups in stool output during the first four hours, time to successful rehydration, volume of ORS required for rehydration, urinary output, and vomiting. This was independent of rotavirus-associated infection. An L-glutamine-containing glucose-free ORS seems not to offer greater clinical benefit than the standard WHO-ORS in mildly-to-moderately-dehydrated children with acute non-cholera diarrhoea

Does an L-glutamine-containing, Glucose-free, Oral Rehydration Solution Reduce Stool Output and Time to Rehydrate in Children with Acute Diarrhoea? A Double-blind Randomized Clinical Trial

This study assessed whether an oral rehydration solution (ORS) in which glucose is replaced by L-glutamine (L-glutamine ORS) is more effective than the standard glucose-based rehydration solution recommended by the World Health Organization (WHO-ORS) in reducing the stool volume and time to rehydrate in acute diarrhoea. In a double-blind, randomized controlled trial in a Mexican hospital, 147 dehydrated children, aged 1-60 month(s), were assigned either to the WHO-ORS (74 children), or to the L-glutamine ORS (73 children) and followed until successful rehydration. There were no significant differences between the groups in stool output during the first four hours, time to successful rehydration, volume of ORS required for rehydration, urinary output, and vomiting. This was independent of rotavirus-associated infection. An L-glutamine-containing glucose-free ORS seems not to offer greater clinical benefit than the standard WHO-ORS in mildly-to-moderately-de\uadhydrated children with acute non-cholera diarrhoea

National Prevalence and Trends of HIV Transmitted Drug Resistance in Mexico

BACKGROUND: Transmitted drug resistance (TDR) remains an important concern for the management of HIV infection, especially in countries that have recently scaled-up antiretroviral treatment (ART) access. METHODOLOGY/PRINCIPAL FINDINGS: We designed a study to assess HIV diversity and transmitted drug resistance (TDR) prevalence and trends in Mexico. 1655 ART-naïve patients from 12 Mexican states were enrolled from 2005 to 2010. TDR was assessed from plasma HIV pol sequences using Stanford scores and the WHO TDR surveillance mutation list. TDR prevalence fluctuations over back-projected dates of infection were tested. HIV subtype B was highly prevalent in Mexico (99.9%). TDR prevalence (Stanford score>15) in the country for the study period was 7.4% (95% CI, 6.2∶8.8) and 6.8% (95% CI, 5.7∶8.2) based on the WHO TDR surveillance mutation list. NRTI TDR was the highest (4.2%), followed by NNRTI (2.5%) and PI (1.7%) TDR. Increasing trends for NNRTI (p = 0.0456) and PI (p = 0.0061) major TDR mutations were observed at the national level. Clustering of viruses containing minor TDR mutations was observed with some apparent transmission pairs and geographical effects. CONCLUSIONS: TDR prevalence in Mexico remains at the intermediate level and is slightly lower than that observed in industrialized countries. Whether regional variations in TDR trends are associated with differences in antiretroviral drug usage/ART efficacy or with local features of viral evolution remains to be further addressed

Patrones biogeográficos de la avifauna de la Sierra Madre del Sur Biogeographic patterns of the avifauna of the Sierra Madre del Sur

Analizamos la avifauna de 26 subcuencas de la provincia biótica de la Sierra Madre del Sur y sus relaciones biogeográficas utilizando el análisis de parsimonia de endemismos (PAE). A partir de información distributional de las especies obtenida de la base de datos del Atlas de las aves de México y de la literatura disponible, construimos una matriz de datos para 26 subcuencas y 437 especies. Se obtuvo un cladograma que sugiere la existencia de 3 grupos de subcuencas: el primero agrupa subcuencas de climas áridos, ubicadas geográficamente de norte a sureste en el estado de Oaxaca; el segundo, otras subcuencas de ambientes climáticos subhúmedos, y el tercero, las restantes subcuencas de ambientes climáticos húmedos de mayor complejidad ambiental.<br>We analyzed the avifauna of 26 sub-basins of the Sierra Madre del Sur biotic province and their biogeographical relationships applying a parsimony analysis of endemicity (PAE). Based on the distributional information of the species obtained from the Atlas de las aves de México and published literature, we built a data matrix for 26 sub-basins and 437 species. The single cladogram obtained suggests the existence of three groups of sub-basins:the first with 5 sub-basins from arid environments, geographically located in north-southeastern Oaxaca; the second with another 5 sub-basins form subhumid environments; and the third one with the remaining sub-basins, from humid and environmentally more complex habitats

The Expression of PNPLA3 Polymorphism could be the Key for Severe Liver Disease in NAFLD in Hispanic Population

Background: Nonalcoholic fatty liver disease (NAFLD) encompasses: fatty liver (SS), steatohepatitis (NASH) with or without fi-brosis and cirrhosis. Patatine-like phosphatas in domain 3 (PNPLA3; adiponutrin; SNP rs738409 C/G, M148I) shows anabolic and catabolic activities on lipid metabolism and significant association to fatty liver content; however, I148M demographics and ethnics, as its role with NAFLD have not been fully elucidated. Material and methods: PNPLA3 genotyping from peripheral blood DNA by polymerase chain reaction (PCR) and direct sequencing, 211 patients diagnosed with NAFLD including SS, NASH and fibrosis spectrum. Results: Eighty nine per cent showed the G risk allele [CC: 23 (10.5%), GC: 73 (34.7%), GG 115 (54.7%)], the allele frequency was 77%, NASH (71%), SS (80%) and fibrosis (73%). GG genotype carriers showed 3.8 times (CI 95%: 3.03 - 4.79) of increased risk of steatohepatitis and 2.3 times more (CI 95%: 1.77 ~ 3.23) risk of having liver fibrosis (CC). PNPLA3 (GC, GG) conditioned higher probability of low levels of HDL cholesterol (p 0.675 (p < 0.001) and altered serum alanine aminotransferase (p < 0.05). Conclusion: PNPLA3 expression in Hispanics could be decisive in NAFLD pathogenesis, it's highly prevalent and it's a key to condition and determine the spectrum associated, SS, NASH and fibrosis

Real Time Monitoring of Children, and Adults with Mental Disabilities Using a Low-Cost Non-Invasive Electronic Device

There are a growing number of small children—as well as adults—with mental disabilities (including elderly citizens with Alzheimer’s disease or other forms of age-related dementia) that are getting lost in rural and urban areas for various reasons. Establishing their location within the first 72 h is crucial because lost people are exposed to all kinds of adverse conditions and in the case of the elderly, this is further aggravated if prescribed medication is needed. Herein we describe a non-invasive, low-cost electronic device that operates constantly, keeping track of time, the geographical location and the identification of the subject using it. The prototype was made using commercial low-cost electronic components. This electronic device shows high connectivity in open and closed areas and identifies the geographical location of a lost subject. We freely provide the software and technical diagrams of the prototypes