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GL Paniagua-Contreras,1 E Monroy-Pérez,1 CE Díaz-Velásquez,2 A Uribe-García,1 A Labastida,3 F Peñaloza-Figueroa,3 P Domínguez-Trejo,4 LR García,4 F Vaca-Paniagua,2,5,6 S Vaca11Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, México; 2Laboratorio Nacional en Salud: Diagnóstico Molecular y Efecto Ambiental en Enfermedades Crónico- Degenerativas, FES-Iztacala, UNAM, Tlalnepantla, Edo. de México, México; 3OMICS Analysis, Ciudad de México, México; 4Instituto Mexicano del Seguro Social, México City, México; 5Subdirección de Investigación Básica, Instituto Nacional de Cancerología, México City, México; 6Unidad de Biomedicina, Facultad de Estudios Superiores Iztacala, Universidad Nacional Autónoma de México, Tlalnepantla, MéxicoBackground: Escherichia coli is the main bacterium associated with urinary tract infections (UTIs), including cystitis and pyelonephritis. Uropathogenic E. coli (UPEC) harbors numerous genes that encode diverse virulence factors contributing to its pathogenicity. The treatment of UTIs has become complicated due to the natural selection of E. coli strains that are multiresistant to several groups of antibiotics regularly used in clinical settings such as hospitals. Genomic reports of the global composition and distribution of the antibiotic resistance and virulence genes of these pathogenic strains are lacking in the Mexican population.Purpose and methods: The aim of this study was to globally characterize the genomes of a group of UPEC strains by massive parallel sequencing to determine the prevalence and distribution of virulence and antibiotic resistance genes associated with different serotypes and phylogenetic groups.Results: The strains exhibited 138-197 virulence genes and 29 antibiotic resistance genes related to antibiotics that are commonly used in clinical practice.Conclusions: These findings are relevant to the definition of new strategies for treating urinary tract infections in public hospitals and private practice. To further define the epidemiological distribution and composition of these virulence and antibiotic resistance genes, larger studies are needed.Keywords: whole-genome sequencing, virulence genes, antibiotic resistance genes

Abstract: Recently, attention has turned to the possibility that endocrine adiposity hormones, such as leptin, may regulate appetitively motivated behavior by modulating brain dopamine function. By extension, it has been hypothesized that the increased behavioral sensitivity of food-restricted, underweight rats to psychostimulant challenge may be triggered by the accompanying hypoleptinemia. The purpose of the present study was to determine whether two weeks of continuous intracerebroventricular (ICV) infusion of leptin alters the motor-activating effect of d-amphetamine (0.75 mg/kg, IP) in food-restricted rats. Lateral ventricular infusion of leptin, using a regimen that decreases food intake and body weight in ad libitum fed rats (12 μg/day), had no effect on the locomotor response to d-amphetamine in food-restricted rats that were maintained at 80% of prerestriction body weight. This result may indicate that hypoleptinemia is not involved in the induction/maintenance of neuroadaptations that mediate enhanced behavioral sensitivity to psychostimulant challenge. Interestingly, ad libitum fed rats treated with leptin displayed an increased locomotor response to d-amphetamine that was most prominent 3–5 days after termination of the infusion. Body weights and d-amphetamine sensitivity of these subjects returned to control values by 8–10 days postinfusion. The enhanced behavioral sensitivity to d-amphetamine in leptin-treated ad libitum fed rats may be a by-product of adipose depletion and, if so, would further support involvement of a peripheral signal other than hypoleptinemia in the modulation of central sensitivity to psychostimulant challenge. [Copyright &y& Elsevier]

Presents a study to evaluate behavioral and cellular effects of the preferential D(3) dopamine receptor antagonist U99194A. Methods; Results; Conclusion that results indicate that U99194A has psychostimulant-like effects on motor activity and striatal c-fos expression that are dependent upon the D(1) DA receptor.

Abstract Background Helicobacter pylori has been strongly associated with chronic gastritis, peptic and duodenal ulcers, and it is a risk factor for gastric cancer. Three major virulence factors of H. pylori have been described: the vacuolating toxin (VacA), the cytotoxin-associated gene product (CagA) and the adhesion protein BabA2. Since considerable geographic diversity in the prevalence of H. pylori virulence factors has been reported, the aim of this work was to establish the H. pylori and vacA, cagA and babA2 gene status in 238 adult patients, from a marginal urban area of Mexico, with chronic gastritis. Methods H. pylori was identified in cultures of gastric biopsies by nested PCR. vacA and cagA genes were detected by multiplex PCR, whereas babA2 gene was identified by conventional PCR. Results H. pylori-positive biopsies were 143 (60.1%). All H. pylori strains were vacA+; 39.2% were cagA+; 13.3% were cagA+ babA2+ and 8.4% were babA2+. Mexican strains examined possessed the vacA s1, m1 (43.4%), s1, m2 (24.5%), s2, m1 (20.3%) and s2, m2 (11.9%) genotypes. Conclusion These results show that the Mexican patients suffering chronic gastritis we have studied had a high incidence of infection by H. pylori. Forty four percent (63/143) of the H. pylori strains analyzed in this work may be considered as highly virulent since they possessed two or three of the virulence markers analyzed: vacA s1 cagA babA2 (9.8%, 14/143), vacA s1 babA2 (4.9%, 7/143), and vacA s1 cagA (29.4%, 42/143). However, a statistically significant correlation was not observed between vacAs1, cagA and babA2 virulence markers (χ2 test; P > 0.05).

Abstract Background Diarrhoeal diseases constitute a major public health problem, particularly in the developing world, where the rate of mortality and morbidity is very high. The purpose of this study was to conduct a 2 years and 3 months study in order to determine the prevalence of five enteropathogen diarrheogenic agents in Mexico City. Methods Faecal samples were obtained from 300 Mexican children diagnosed as positive for diarrhoea, aged > 2 to < 12 years old, and from 80 children matched for age but with no symptoms of the disease (control group). Two multiplex PCR were used to detect Escherichia coli, Salmonella spp., and Shigella spp. In addition, the two protozoan parasites Entamoeba histolytica/Entamoeba dispar and Giardia intestinalis were detected by conventional methods. Results All diarrhoeal samples were positive for one or more enteropathogens. The most common enteropathogens in diarrhoeal samples were E. histolytica/E. dispar (70.3%), Salmonella (ohio 28.3%; typhimurium 16.3%; infantis 8%; anatum 0.6%; Newport 0.3%), G. intestinalis (33%), E. coli (ETEC 13.3%; EPEC 9.3%; VTEC 8.6%; EIEC 1%) and Shigella spp. (flexneri 1.6%, sonnei 1%). Infections by two (24%) three (16%) and four (12%) pathogens were observed. Conclusion This study revealed that 52% of the patients were infected by more than one enteropathogen, notably E. histolitica/E. dispar and Salmonella ohio. These results are useful for clinicians to improve the empiric treatment used in such cases.

The circadian rhythms generated by the master biological clock located in the brain's hypothalamus influence central physiological processes. At the molecular level, a core set of clock genes interact to form transcription-translation feedback loops that provide the molecular basis of the circadian rhythm. In animal models of disease, a desynchronization of clock genes in peripheral tissues with the central master clock has been detected. Interestingly, patients with vascular dementia have sleep disorders and irregular sleep patterns. These alterations in circadian rhythms impact hormonal levels, cardiovascular health (including blood pressure regulation and blood vessel function), and the pattern of expression and activity of antioxidant enzymes. Additionally, oxidative stress in vascular dementia can arise from ischemia-reperfusion injury, amyloid-beta production, the abnormal phosphorylation of tau protein, and alterations in neurotransmitters, among others. Several signaling pathways are involved in the pathogenesis of vascular dementia. While the precise mechanisms linking circadian rhythms and vascular dementia are still being studied, there is evidence to suggest that maintaining healthy sleep patterns and supporting proper circadian rhythm function may be important for reducing the risk of vascular dementia. Here, we reviewed the main mechanisms of action of molecular targets related to the circadian cycle and oxidative stress in vascular dementia.

In recent years the most studied carbon allotrope has been graphene, due to the outstanding properties that this two-dimensional material exhibits; however, it turns out to be a difficult material to produce, pattern, and transfer to a device substrate without contamination. Carbon microelectromechanical systems are a versatile technology used to create nano/micro carbon devices by pyrolyzing a patterned photoresist, making them highly attractive for industrial applications. Furthermore, recent works have reported that pyrolytic carbon material can be graphitized by the diffusion of carbon atoms through a transition metal layer. In this work we take advantage of the latter two methods in order to produce multilayer graphene by improving the molecular ordering of photolithographically-defined pyrolytic carbon microstructures, through the diffusion (annealing) of carbon atoms through nickel, and also to eliminate any further transfer process to a device substrate. The allotropic nature of the final carbon microstructures was inspected by Raman spectroscopy (Average I D / I G of 0.2348 ± 0.0314) and TEM clearly shows well-aligned lattice planes of 3.34 Å fringe separation. These results were compared to measurements made on pyrolytic carbon (Average I D / I G of 0.9848 ± 0.0235) to confirm that our method is capable of producing a patterned multilayer graphene material directly on a silicon substrate., (© 2021 IOP Publishing Ltd.)

Background/purpose: The aim of this study was to characterize the Staphylococcus aureus strains isolated from periodontal lesions of patients, to determine the expression of genes involved in cell adhesion upon their infection of human epithelial cells using an in vitro model, its biofilm formation, and its resistance to antibiotics., Methods: S. aureus was analysed by PCR, Kirby-Bauer, and pulsed-field gel electrophoresis (PFGE), measuring gene expression by real-time PCR after infection of human cells in vitro., Results: S. aureus was identified in 18.6% (50/268) of the samples. All strains (n = 50) possessed the virulence genes spa (Staphylococcal protein A), coa (coagulase), and icaAB (intercellular adhesin); 96% (n = 48) possessed clfB (clumping factor B), and 88% (n = 44) possessed ebps (elastin-binding protein) and sdrD (serine aspartate repeat protein D). All strains were resistant to methicillin, ampicillin, dicloxacillin, cefotaxime, and penicillin, and were multidrug resistant to 6-12 antibiotics. PFGE analysis showed 37 different pulsed-field types and most strains (60.4%) had a unique pulsed-field type. Twenty-four distinct combinations of virulence genes and antibiotic-resistant phenotypes were identified., Conclusion: Although S. aureus has been considered a transient member of the oral microbiota, our results indicate a high-level expression of virulence genes and multidrug resistance in the strains isolated from periodontal lesions. These strains might complicate the successful treatment of the disease., (Copyright © 2019. Published by Elsevier B.V.)

Background and Aim: Obesity increases the risk of atrial fibrillation (AF) while it may impact the outcome of patients with AF. The clinical implications of this relationship are not completely clear. We aimed to analyze the association of traditional anthropometric measures of excessive adiposity with 12 month case fatality rate (CFR) in patients with AF., Methods: This was a multicenter, longitudinal, observational study on adults with documented AF, excluding records of AF secondary to reversible causes. Anthropometric variables were registered at baseline, and a central committee validated the 12 month outcomes., Results: We studied 1193 patients (median age: 69.14 years, 55.2% women). At baseline, rhythm control was established for 476 (39.9%) subjects, while frequency control was offered to 717 (60.1%) participants. The 12 month all-cause CFR was 8.9%. A high basal body mass index (BMI), waist-to-height ratio (WHtR) and waist circumference (WC) were associated with lower CFR in bivariate analyses. In a Cox-proportional hazards model, variables associated with 12 month all-cause CFR were BMI categories (HR: 0.736, 95% CI: 0.584-0.928), chronic heart failure (HR: 1.738, 95% CI: 1.127-2.680), chronic kidney disease (HR: 2.269, 95% CI: 1.162-4.429) and carotid stenosis >50% (HR: 5.342, 95% CI: 1.661-17.181)., Conclusion: The risk of death at one year in patients with AF is inversely associated with a high BMI and directly associated with the presence of chronic kidney disease, carotid stenosis, and chronic heart failure in this cohort of patients with AF. The causes and implications of this apparent obesity paradox should be addressed in the future., (Copyright © 2021 IMSS. Published by Elsevier Inc. All rights reserved.)

Informal caregivers are the main providers of care for the elderly. The aim of this study is to examine the predictive value of different variables regarding caregivers and their elderly patients with respect to the caregiver's burden. A convenience sample of 688 informal caregivers and 688 elderly people from Ecuador was surveyed. Only households with one caregiver and one elderly person were considered for the study. For informal caregivers, the following standardized measures were obtained: burden (Zarit Burden Interview), neuroticism (Eysenck Personality Questionnaire Revised-Abbreviated, EPQR-A), caregiver's general health (GHQ-12), and social support (modified Duke-UNC Functional Social Support Questionnaire, FSSQ11). For the elderly, we employed standardized measures of cognitive function (short portable mental status questionnaire, SPMSQ), Pfeiffer's test, and functional dependency (Barthel scale/Index, BI). Females were over-represented in caregiving and reported significantly higher burden levels than those of males. In both male and female caregivers, the burden was best predicted by the time of caring, neuroticism, and elderly cognitive impairment. However, some predictors of burden were weighted differently in males and females. The functional independence of the elderly was a significant predictor of burden for male caregivers but not females, while caregiver competence was a significant predictor for females but not males. These variables accounted for more than 88% of the variability in informal caregivers.

The pathogenicity of Escherichia coli strains that cause cervico-vaginal infections (CVI) is due to the presence of several virulence genes. The objective of this study was to define the variability regarding the genotype of antibiotic resistance, the transcription profiles of virulence genes after in vitro infection of the vaginal cell line A431 and the phylogroup composition of a group of cervico-vaginal E. coli strains (CVEC). A total of 200 E. coli strains isolated from Mexican women with CVI from two medical units of the Mexican Institute of Social Security were analysed. E. coli strains and antibiotic resistance genes were identified using conventional polymerase chain reaction (PCR), and phylogroups were identified using multiplex PCR. Virulence gene transcription was measured through reverse-transcriptase real-time PCR after infection of the vaginal cell line A431. The most common antibiotic resistance genes among the CVEC strains were aac(3)II, TEM, dfrA1, sul1, and qnrA. The predominant phylogroup was B2. The genes most frequently transcribed in these strains were fimH, papC, irp2, iroN, kpsMTII, cnf1, and ompT, mainly in CVEC strains isolated from chronic and occasional vaginal infections. The strains showed a large diversity of transcription of the virulence genes phenotype and antibiotic resistance genotype, especially in the strains of phylogroups, B2, A, and D. The strains formed 2 large clusters, which contained several subclusters. The genetic diversity of CVEC strains was high. These strains have a large number of transcription patterns of virulence genes, and one-third of them carry three to seven antibiotic resistance genes., Competing Interests: The authors have declared that no competing interests exist.