Detection of rotavirus and norovirus among children with acute gastroenteritis in Merida and Chihuahua cities, Mexico.

INTRODUCTION: Infantile acute gastroenteritis (AGE) is a leading cause of morbidity and mortality, particularly in developing countries. The most frequent etiological agents of viral gastroenteritis in children are adenovirus, astrovirus, rotavirus, and norovirus, the last two, leading causes. Thus, the aim of this study was to identify the presence of these two viruses in children with AGE, from two cities located in the Southeast and the Northwest regions of México. METHODOLOGY: HuNoVs were detected and characterized by RT-PCR and sequencing, while RVs were detected by RNA electrophoresis. RESULTS: The presence of RV and HuNoV was evaluated in 81 stool samples; 37 were collected between April and July 2013 from patients with acute diarrhea in Merida, and 44 were collected between January and June 2017 in Chihuahua, who attended health services. Despite vaccination, RV resulted in the predominant viruses detected, with 30.8% (25/81) positivity, while HuNoV infection was present in 8.6% (7/81) of the stool samples; GII strains were identified circulating in the Southeast, while GI strains were identified in the Northwest. Moreover, co-infections with both viruses were detected at a prevalence rate of 2.4% (2/81). CONCLUSIONS: The circulation of RV and HuNoV in the country is continuous and should be constantly monitored due to their impact on public health.

Pepper growth promotion and biocontrol against Xanthomonas euvesicatoria by Bacillus cereus and Bacillus thuringiensis formulations.

Background: Bacillus genus has been used in horticultural crops as a biocontrol agent against insect pests, microbial phytopathogens, and plant growth-promoting bacteria (PGPB), representing an alternative to agrochemicals. In particular, B. cereus (Bc) and B. thuringiensis (Bt) have been studied for their fungicidal and insecticidal activities. However, their use as biofertilizer formulations and biocontrol agents against phytopathogenic bacteria is limited. Objective: To evaluate Bc and Bt formulations as PGPB and biocontrol agents against the bacterial spot agent Xanthomonas euvesicatoria (Xe) in greenhouse-grown chili peppers. Methods: Bc and Bt isolates obtained from soil samples were identified and characterized using conventional biochemical and multiplex PCR identification methods. Bioassays to determine Bc and Bt isolates potential as PGPB were evaluated on chili pepper seedlings in seedbeds. In addition, formulations based on Bc (F-BC26 and F-BC08) and Bt (F-BT24) strains were assessed as biofertilizers on pepper, under controlled conditions. Furthermore, in vitro antagonism assays were performed by confronting Bc and Bt isolate formulations against Xe isolates in direct (foliage) and indirect (resistance induction) phytopathogen biocontrol assays on pepper plants, which were grown under controlled conditions for 15 d after formulations treatment. Results: Isolates were identified as Bc and Bt. Formulations significantly improved pepper growth in seedbeds and pots, whereas in vitro bioassays demonstrated the bactericidal effect of Bc and Bt strains against Xe isolates. Furthermore, assays showed significant plant protection by F-BC26, F-BC08, and F-BT24 formulated strains against Xe. Conclusion: Results indicated that F-BT24 and F-BC26 isolates formulations promoted pepper growth and protected it against Xanthomonas euvesicatoria.

Prevalence of Xanthomonas euvesicatoria (formally X. perforans) associated with bacterial spot severity in Capsicum annuum crops in South Central Chihuahua, Mexico.

BACKGROUND: Xanthomonas spp. causes bacterial spot disease, which reduces quality and yield of pepper crops in Mexico. Identification of phytopathogen species is necessary to implement more effective control strategies. OBJECTIVE: The aim of this study was to isolate and identify infecting Xanthomonas species in South Central Chihuahua pepper-producing areas. METHODS: Diseased plants were collected from 30 cultivation lots and bacteria were isolated from damaged tissues. Potential causative agents were isolated, identified, and characterized by biochemical and molecular analysis. Pathogenicity tests from each isolate were then performed on 30-d-old pepper seedlings, exposing five leaves to 10 µL of 1 × 108 CFU/mL bacterial suspensions of each isolate, using sterile distilled water as a control. Disease severity was determined after 10 d by calculating leaf damage percentage. Furthermore, we evaluated the susceptibility of the highest bacterial spot severity-causing isolates (13 isolates) to copper sulphate (CuS), copper gluconate (CuG), copper oxychloride + oxytetracycline hydrochloride (Cu + Ox), gentamicin + oxytetracycline hydrochloride (Gen + Ox), and gentamicin sulphate (GenS). Copper-resistance genes (copLAB) were detected by PCR analysis among isolates. RESULTS: Thirty-seven foliage isolates were identified as Xanthomonas euvesicatoria (14%), which were associated with bacterial spot disease in jalapeño pepper. Tested Xanthomonas isolates were resistant to Cu-based compounds, but susceptible to Cu + Ox. All isolates were susceptible to Gen + Ox and GenS. CopLAB genes were detected in all but one strain. CONCLUSIONS: X. euvesicatoria (formally X. perforans) may be considered as an emerging pathogen of bacterial spot pepper in Mexico. Among disease management strategies, alternatives to copper should be taken into consideration.

Plasma marker for systemic inflammation is increased in Mexican Tarahumara following ultra-distance running.

OBJECTIVES: Previous studies have suggested that acute exercise-induced cardiac and kidney damage following ultra-distance running is low in Mexican Tarahumara even though C-reactive protein (CRP) remained elevated 24 hours post-race. We aimed to study if the plasma biomarker, soluble urokinase-type plasminogen activator receptor (suPAR), could replace or complement CRP as a systemic inflammation biomarker in Tarahumara men and women following ultra-distance running. METHODS: Plasma samples were collected pre-race and at three to six different time points post-race in Mexican Tarahumara competing in three independent ultramarathons; men running 78 km (GroupI, n = 9), women running 52 km (GroupII, n = 3), and men running 63 km (GroupIII, n = 10). Baseline anthropometry, blood pressure, glycated hemoglobin, and hemoglobin were measured, aerobic fitness was estimated by submaximal step test, absolute and relative running intensity assessed using combined heart rate and accelerometry. Plasma was collected pre- and post-race to analyze concentrations of suPAR, and-for women only-a panel of inflammatory, cardiac and kidney plasma biomarkers. Mixed-effect models were used to evaluate the effect of ultramarathon running on plasma suPAR concentrations. RESULTS: Compared to pre-race values, suPAR was significantly elevated in plasma <5 minutes after the three ultramarathon races (70%-109% increase of the mean for the three groups). Furthermore, plasma suPAR remained significantly elevated up to 6 hours post-race for all three groups of runners independent of running intensity. CONCLUSIONS: The results suggest that suPAR can complement, but not replace CRP following ultra-distance running in Tarahumara men and women.

Transient cardiac dysfunction but elevated cardiac and kidney biomarkers 24 h following an ultra-distance running event in Mexican Tarahumara.

BACKGROUND: The Mexican Tarahumara are accustomed to running ultra-distance races. No data exist on the acute physiological changes following ultra-distance running and physiological-biomarker associations in this population. Thus, we aimed to investigate the acute impact (≤ 24 h) on functional and biochemical changes of the cardiac muscle and biochemical changes associated with kidney function following a 63-km ultra-distance race with an altitude difference of 1800 m in Mexican Tarahumara athletes. METHODS: Ten Tarahumara male athletes (mean ± SD age = 29.9 ± 6.6 years) volunteered to participate in the study. VO2max was assessed by a sub-maximal step test individually calibrated combining heart rate and accelerometry. Standard transthoracic echocardiography methodology and venipuncture blood tests were carried out at four time points: pre-race, immediately post-race, 6 h, and 24 h post-race. RESULTS: Estimated mean VO2max was 54.5 (± 8.8) mL O2 min-1 kg-1 and average physiological activity intensity was 746 (± 143) J min-1 kg -1 (~ 11.5 METs). When compared to pre-race values, significant changes in left ventricular ejection fraction (LVEF) and LV end-diastolic volume (- 15%, p < 0.001 for both parameters), cardiac output (39%, p < 0.001), and maximal longitudinal velocity (- 13%, p < 0.009) were seen post-race with LVEF also being decreased at < 6 h post-race (- 8%, p < 0.014). Plasma biomarkers mid-regional pro-atrial natriuretic peptide, copeptin-ultra sensitive, and high-sensitivity cardiac troponin T remained significantly elevated at 24 h post-race, and the two latter were inversely associated with LVEF (p < 0.04). Kidney dysfunction was indicated by increased post-race copeptin-ultra sensitive. CONCLUSIONS: The athletes participating in this study had acute transient cardiac dysfunction as assessed by echocardiography but elevated cardiac and kidney biomarkers at 24 h following a 63-km race with extreme altitude variation.

Prevalence of Rotavirus Genogroup A and Norovirus Genogroup II in Bassaseachic Falls National Park Surface Waters in Chihuahua, Mexico.

In areas lacking potable water treatment, drinking contaminated water may represent a public health threat. In addition to enteropathogenic bacteria and parasites, fecal contamination in water environments is associated with the transmission of enteric viruses and other causal agents of infectious disease. Rotavirus and norovirus are the main enteric viral agents responsible for diarrheic outbreaks. The aim of the present study was to detect seasonal variation of rotavirus and norovirus in the surface water at Bassaseachic Falls National Park during 2013. Rivers and streams within and nearby this park were sampled once in each season during 2013. Viral concentration was carried out by a handmade filtration equipment, using a commercial electropositive membrane coupled with the virus absortion elution technique (VIRADEL©). Detection of rotavirus and norovirus was performed by SYBR Green reverse transcription-real time polymerase chain reaction (SYBR GREEN© RT-qPCR) analyses. Norovirus genogroup II was detected in samples collected in June and October 2013. In the case of rotavirus, genogroup A was detected in March and June. The presence of rotavirus and norovirus was related to viral acute diarrhea in children less than five years of age, who were inhabiting the sampled areas. This may indicates that the contaminated water was potentially a risk factor for regional diarrheic outbreaks.

Multidrug-Resistant Bacteria Isolated from Surface Water in Bassaseachic Falls National Park, Mexico.

Bacterial pathogens are a leading cause of waterborne disease, and may result in gastrointestinal outbreaks worldwide. Inhabitants of the Bassaseachic Falls National Park in Chihuahua, Mexico show seasonal gastroenteritis problems. This aim of this study was to detect enteropathogenic microorganisms responsible for diarrheal outbreaks in this area. In 2013, 49 surface water samples from 13 selected sampling sites along the Basaseachi waterfall and its main rivers, were collected during the spring, summer, autumn, and winter seasons. Fecal and total coliform counts were determined using standard methods; the AutoScan-4 system was used for identification of isolates and the antibiotic resistance profile by challenging each organism using 21 antibiotics. Significant differences among seasons were detected, where autumn samples resulted in the highest total (p < 0.05) and fecal (p < 0.001) coliform counts, whereas the lowest total coliform counts were recorded in spring. Significant differences between sampling sites were observed, where samples from sites 6, 8, and 11 had the highest total coliform counts (p < 0.009), whereas samples from site 9 exhibited the lowest one. From the microbiological analysis, 33 bacterial isolates from 13 different sites and four sampling seasons were selected; 53% of isolates were resistant to at least one antibiotic, and 15% exhibited a multidrug resistance (MDB) phenotype. MDB were identified as Klebsiella oxytoca (two out of four identified isolates), Escherichia coli (2/7), and Enterobacter cloacae (1/3). In addition, some water-borne microorganisms exhibited resistance to cefazoline, cefuroxime, ampicillin, and ampicillin-sulbactam. The presence of these microorganisms near rural settlements suggests that wastewater is the contamination source, providing one possible transmission mechanism for diarrheal outbreaks.

Genetic and serologic surveillance of rotavirus with P[8] and P[4] genotypes in feces from children in the city of Chihuahua, northern Mexico

Rotavirus vaccine was developed using the most prominent G and P genotypes circulating in children population. Therefore, severe gastroenteritis has been reduced around the world. This study investigated the G and P rotavirus genotypes circulating in children from two hospitals in the city of Chihuahua, Mexico. Additionally, polyclonal antibodies against Rotavirus Wa strain were used to determine their homotypic and heterotypic reactivity to both P[8] and P[4] genotypes. G1, G2, and G3 VP7 genotypes and P[8] and P[4] VP4 genotypes were detected in common and uncommon combinations as well as mixed infectious. The predominant combination was G1P[8]. Phylogenetic analysis of VP4 gene revealed the presence of P[8]-1 and P[8]-3 lineages of P[8] genotype and P[4]-5 lineage of P[4] genotype. All but five G1P[8] rotavirus were detected by polyclonal anti-Rotavirus Wa strain. Mutation analysis revealed differences in three of the four neutralizing epitopes previously reported to VP8* subunit of VP4 protein. Results of this study offer insights over genetic variants of field rotavirus that could be detected in a homotypic and heterotypic way by antibodies elicited to rotavirus with P[8] genotype (AU)

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Prenatal Exposure to Sodium Arsenite Alters Placental Glucose 1, 3, and 4 Transporters in Balb/c Mice.

Inorganic arsenic (iAs) exposure induces a decrease in glucose type 4 transporter (GLUT4) expression on the adipocyte membrane, which may be related to premature births and low birth weight infants in women exposed to iAs at reproductive age. The aim of this study was to analyze the effect of sodium arsenite (NaAsO2) exposure on GLUT1, GLUT3, and GLUT4 protein expression and on placental morphology. Female Balb/c mice (n = 15) were exposed to 0, 12, and 20 ppm of NaAsO2 in drinking water from 8th to 18th day of gestation. Morphological changes and GLUT1, GLUT3, and GLUT4 expression were evaluated in placentas by immunohistochemical and image analysis and correlated with iAs and arsenical species concentration, which were quantified by atomic absorption spectroscopy. NaAsO2 exposure induced a significant decrease in fetal and placental weight (P < 0.01) and increases in infarctions and vascular congestion. Whereas GLUT1 expression was unchanged in placentas from exposed group, GLUT3 expression was found increased. In contrast, GLUT4 expression was significantly lower (P < 0.05) in placentas from females exposed to 12 ppm. The decrease in placental GLUT4 expression might affect the provision of adequate fetal nutrition and explain the low fetal weight observed in the exposed groups.

Genetic and serologic surveillance of rotavirus with P[8] and P[4] genotypes in feces from children in the city of Chihuahua, northern Mexico.

Rotavirus vaccine was developed using the most prominent G and P genotypes circulating in children population. Therefore, severe gastroenteritis has been reduced around the world. This study investigated the G and P rotavirus genotypes circulating in children from two hospitals in the city of Chihuahua, Mexico. Additionally, polyclonal antibodies against Rotavirus Wa strain were used to determine their homotypic and heterotypic reactivity to both P[8] and P[4] genotypes. G1, G2, and G3 VP7 genotypes and P[8] and P[4] VP4 genotypes were detected in common and uncommon combinations as well as mixed infectious. The predominant combination was G1P[8]. Phylogenetic analysis of VP4 gene revealed the presence of P[8]-1 and P[8]-3 lineages of P[8] genotype and P[4]-5 lineage of P[4] genotype. All but five G1P[8] rotavirus were detected by polyclonal anti-Rotavirus Wa strain. Mutation analysis revealed differences in three of the four neutralizing epitopes previously reported to VP8* subunit of VP4 protein. Results of this study offer insights over genetic variants of field rotavirus that could be detected in a homotypic and heterotypic way by antibodies elicited to rotavirus with P[8] genotype. [Int Microbiol 2016; 19(1):27-32].

Normalization of elevated cardiac, kidney, and hemolysis plasma markers within 48 h in Mexican Tarahumara runners following a 78 km race at moderate altitude.

OBJECTIVES: The aim of this study was to examine to what extent extreme endurance exercise results in changes of plasma markers associated with cardiac and renal damage, as well as hemolysis in male, Mexican Tarahumara runners. METHODS: Ten Tarahumara runners (mean (sd) age of 38 (12) years) participated in a 78 km race in Chihuahua, Mexico at 2,400 m above sea level. Cardiac, kidney, and hematology plasma markers were measured pre-race and <5 min, 1 h, 3 h, 6 h, 24 h, and 48 h post-race. Anthropometry, blood pressure, pulse rate, electrocardiography, HbA1c, hemoglobin and VO2max (estimated from heart rate following step test) were assessed pre-race, while physical activity energy expenditure and intensity were estimated during the race, and oxygen partial pressure saturation (SpO2 ) <30 min post-race. RESULTS: Estimated mean VO2max was 48 (9) mLO2 min(-1) kg(-1) and relative intensity during the race was 68 (11)%VO2 max. Mean SpO2 was 92 (3)% <30 min post-race. Plasma concentrations of especially total creatine kinase, creatine kinase-MB isoform, and haptoglobin changed significantly from pre-race values (P < 0.001) up to 24 h post-race, but had returned to pre-race values after 48 h. The plasma concentrations of mid-regional proatrial natiuretic peptide and copeptin returned to pre-race concentrations after 1 and 6 h, respectively. CONCLUSIONS: Altered cardiac, renal, and hemolysis plasma markers were normalized after 48 h following 78 km of running, suggesting that the impact of exercise-induced cardiac and kidney damage as well as hemolysis in the Mexican Tarahumara is low.