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Streamlit is an open-source Python coding framework for building web-applications or "web-apps" and is now being used by researchers to share large data sets from published studies and other resources. Here we present Stmol, an easy-to-use component for rendering interactive 3D molecular visualizations of protein and ligand structures within Streamlit web-apps. Stmol can render protein and ligand structures with just a few lines of Python code by utilizing popular visualization libraries, currently Py3DMol and Speck. On the user-end, Stmol does not require expertise to interactively navigate. On the developer-end, Stmol can be easily integrated within structural bioinformatic and cheminformatic pipelines to provide a simple means for user-end researchers to advance biological studies and drug discovery efforts. In this paper, we highlight a few examples of how Stmol has already been utilized by scientific communities to share interactive molecular visualizations of protein and ligand structures from known open databases. We hope Stmol will be used by researchers to build additional open-sourced web-apps to benefit current and future generations of scientists.

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The accumulation of four human pharmaceuticals active compounds (HPhAC) in the muscle of four fish species of the Rio de la Plata Basin were assessed regarding the compound logP and pKa, and fish trophic levels. For Prochilodus lineatus, accumulation was compared to hepatic biotransformation enzymes and fish from two sampling areas with different urbanization degree. Species were the detritivore Prochilodus lineatus, the omnivores Megaleporinus obtusidens and Pimelodus maculatus, and the piscivorous Salminus brasiliensis. Sampling areas were the Inner Rio de la Plata Estuary (RLP), in front of the Buenos Aires Metropolitan Area, and at the Lower Uruguay River (URU), a relatively unpopulated area. Carbamazepine, atenolol, enalapril, and sildenafil concentrations in fish muscle were analyzed by HPLC-MS. EROD, BROD, and GST activities were measured in P. lineatus liver. Average (maximum) concentrations and detection frequency were: Atenolol 24.4 (69.4) µg kg-1, 60%; carbamazepine 5.5 (45.8) µg kg-1, 19%; enalapril 7.0 (56.9) µg kg-1, 28%; sildenafil 17.1 (71.6) µg kg-1, 56%. Enalapril and sildenafil detection in fish was first-time reported. Atenolol and carbamazepine concentrations were positively correlated. No correlation was observed between HPhAC accumulation and logP or pKa. A potential biomagnification trend was observed for atenolol, showing higher accumulation in S. brasiliensis. HPhACs accumulation was higher for P. lineatus collected at URU, but GST and BROD were significantly higher for individuals sampled at RLP and were positively correlated. A significant negative correlation was observed for enalapril and BROD. The study contributes to the knowledge of the accumulation of HPhACs in fish.

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OBJECTIVE: To examine the associations of maternal and child overweight status across multiple time-points with liver fat content in the offspring during young adulthood. DESIGN: Cohort study. SETTING: ELEMENT Cohort in Mexico City. POPULATION: Pregnant women with singleton births (n = 97). METHODS: We quantified hepatic triglyceride content (liver fat content) by proton magnetic resonance spectroscopy (1H MRS) and conventional T2-weighted MRIs (3T scanner) in 97 young adults from the ELEMENT birth cohort in Mexico City. Historical records of the cohort were used as a source of pregnancy, and childhood and adolescence anthropometric information, overweight and obesity (OWOB) were defined. Adjusted structural equation models were run to identify the association between OWOB in different life stages with liver fat content (log-transformed) in young adulthood. MAIN OUTCOME: Maternal OWOB at the time of delivery was directly and indirectly associated with the liver fat content in the offspring at young adulthood. RESULTS: Seventeen percent of the participants were classified as having NAFLD. We found a strong association of OWOB between all periods assessed. Maternal OWOB at time of delivery (ß = 1.97, 95% CI 1.28-3.05), and OWOB status in the offspring at young adulthood (ß = 3.17, 95% CI 2.10-4.77) were directly associated with the liver fat content in the offspring. Also, maternal OWOB was indirectly associated with liver fat content through offspring OWOB status. CONCLUSION: We found that maternal OWOB status is related to fatty liver content in the offspring as young adults, even after taking into account OWOB status and lifestyle factors in the offspring. TWEETABLE ABSTRACT: There was an association between pre-pregnancy overweight and the development of NAFLD in adult offspring.

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The accumulation of 17 human pharmaceuticals (HPs) was investigated in the muscle of three fish species characteristic of the "Rio de la Plata Basin" with different feeding habits and of relevance for human consumption: Megaleporinus obtusidens, Salminus brasiliensis, and Prochilodus lineatus. Fish were sampled in fall and spring from 8 localities distributed along 500 Km of the Uruguay River. Atenolol and carbamazepine were the most frequently detected HPs (>50%), but at concentrations always below 1 µg/kg wet weight (w/w). Hydrochlorothiazide, metoprolol, venlafaxine, propranolol, codeine, and the carbamazepine metabolite, 2-hydroxycarbamazepine, were accumulated at higher levels showing maximum concentrations between 1 and 10 µg/kg (w/w), but infrequently (<50%). The other HPs were always below 1 µg/kg (w/w) and at frequencies lower than 50%. Distinctive accumulation patterns were observed among species at different trophic levels. However, biomagnification trends were not identified for any compound. The highest number and concentration of HPs were found in M. obtusidens (omnivorous), followed by P. lineatus (detritivorous), and lastly S. brasiliensis (piscivorous). The most recurrent HPs (i.e. carbamazepine and atenolol) were present in all species, but others exclusively in one. Geographical variations were only found for carbamazepine and atenolol in M. obtusidens and P. lineatus, showing higher concentrations in localities closer to the Rio de la Plata estuary. Differences in the HPs concentrations among seasons were not identified. Acceptable daily intake and predicted no effect concentrations would indicate that measured muscle concentrations in fish from the Uruguay River do not pose a serious risk for human consumption nowadays. Further studies will be necessary for assessing the potential adverse effects on studied fish species.

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Animal and cross-sectional epidemiological studies suggest that prenatal lead exposure is related to delayed menarche, but this has not been confirmed in longitudinal studies. We analyzed this association among 200 girls from Mexico City who were followed since the first trimester of gestation. Maternal blood lead levels were analyzed once during each trimester of pregnancy, and daughters were asked about their first menstrual cycle at a visit between the ages of 9.8 and 18.1 years. We estimated hazard ratios (HRs) and 95% confidence intervals (CI) for probability of menarche over the follow-up period using interval-censored Cox models, comparing those with prenatal blood lead level ⩾5 µg/dl to those with prenatal blood lead <5 µg/dl. We also estimated HRs and 95% CI with conventional Cox regression models, which utilized the self-reported age at menarche. In adjusted analyses, we accounted for maternal age, maternal parity, maternal education, and prenatal calcium treatment status. Across trimesters, 36-47% of mothers had blood lead levels ⩾5 µg/dl. Using interval-censored models, we found that during the second trimester only, girls with ⩾5 µg/dl prenatal blood lead had a later age at menarche compared with girls with prenatal blood lead levels <5 µg/dl (confounder-adjusted HR=0.59, 95% CI 0.28-0.90; P=0.05). Associations were in a similar direction, although not statistically significant, in the conventional Cox regression models, potentially indicating measurement error in the self-recalled age at menarche. In summary, higher prenatal lead exposure during the second trimester could be related to later onset of sexual maturation.

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BACKGROUND: Bisphenol A (BPA) and phthalates metabolites are linked to a variety of adverse health consequences but studies have not explored their association with growth trajectories. OBJECTIVE: Explore body mass index (BMI) trajectories for tertile exposures to BPA and phthalates metabolites in the third trimester of pregnancy. METHODS: We constructed BMI (kg/m2 ) trajectories from birth to 14 years in a birth cohort of 249 children from Mexico City using tertiles of third trimester maternal urinary concentrations of BPA and phthalates metabolites. Fractional age polynomials and mixed effects models were fit separately by sex. Predicted models were plotted for each metabolite tertile with the covariates mother's education and BMI centered at average values. RESULTS: Highest predicted BMI trajectories for female children were observed for third tertile exposure to the phthalate metabolite mono(2-ethyl-5-carboxypentyl) phthalate. In male children, first tertile exposure to mono-isobutyl phthalate and monobenzyl phthalate and second tertile exposure to mono(2-ethylhexyl) phthalate and mono(2-ethyl-5-hydroxyhexyl) phthalate predicted the highest BMI trajectory by adolescence. There was no relationshsip between BPA and child growth trajectory. CONCLUSIONS: These results suggest sex-specific differences in BMI trajectories by levels of metabolite exposure. Additional studies are needed to consider growth through adolescence in assessing the association of pregnancy exposures on child's BMI.

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AIMS: To isolate and characterize native yeast strains from broilers' environment as feedstuff, faeces and gut, and to evaluate their binding capacity for aflatoxin B1 (AFB1 ). METHODS AND RESULTS: A total of nine yeast strains were isolated: three from feedstuff identified as Pichia kudriavzevii (2) and Clavispora lusitaniae (1), two from gut identified as Candida tropicalis and four from faeces identified as Cl. lusitaniae (3) and Cyberlindnera fabianii (1). AFB1 binding percentages varied among yeast strains and with AFB1 concentrations. To carry out adsorption studies, one strain from each genus and each origin was selected as follows: Cl. lusitaniae and P. kudriavzevii from feedstuff, Cl. lusitaniae and Cy. fabianii from faeces and Ca. tropicalis from gut. The most appropriate concentrations for cells and toxin were 107 cells per ml and 100 ng ml-1 of AFB1 respectively. All the tested yeast strains showed similar adsorption capacities independently of the origin. The adsorption isotherm studies in all yeasts assayed showed behaviour of L type or Langmuir and a varied affinity for the toxin. The stability of the AFB1 -yeast complex demonstrated the irreversibility of the binding process. CONCLUSION: Yeast strains tested in this study constitute potential AFB1 adsorbents and they possess the advantage to be native from the avian environment. SIGNIFICANCE AND IMPACT OF THE STUDY: This study makes a contribution to using native yeasts from broilers' environment for controlling chronic aflatoxicosis in avian production.

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BACKGROUND: Consumption of sugar-sweetened beverages (SSB) has been associated with risk of obesity, but little evidence exists to evaluate if age of introduction and cumulative SSB consumption increases risk in children. OBJECTIVES: The objective of the study was to estimate the relationship between age of introduction and cumulative SSB consumption with risk of obesity in 227 Mexican children. METHODS: SSB intake was measured every 6 months; age of introduction and cumulative consumption during the pre-school period were calculated. Height, weight, waist circumference, SSB intake and other relevant variables were measured at age 8-14 years and obesity defined using standard criteria. RESULTS: All participants were introduced to SSB before age 24 months and most (73%) before 12 months. Early SSB introduction (≤12 months) was not significantly associated with increased odds of obesity (odds ratio [OR] = 2.00, 95% confidence interval [CI]: 0.87, 4.59). However, children in the highest tertile of cumulative SSB consumption, compared with the lowest, had almost three times the odds of general (OR = 2.99, 95% CI: 1.27, 7.00) and abdominal (OR = 2.70, 95% CI: 1.03, 7.03) obesity at age 8-14 years. CONCLUSIONS: High SSB consumption increased the likelihood of obesity in 8-14-year-old children. Our results suggest that SSB intake should be delayed and excessive SSB consumption in pre-school period should be avoided.

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The effect of pH (1.7-3.2) and sugar concentration (64-68 °Brix) on the growth of Zygosaccharomyces rouxii MC9 using response surface methodology was studied. Experiments were carried out in concentrated grape juice inoculated with Z. rouxii at isothermal conditions (23 °C) for 60 days. pH was the variable with the highest effect on growth parameters (potential maximum growth rate and lag phase duration), although the effect of sugar concentration were also significant. In a second experiment, the time for spoilage by this microorganism in concentrated grape juice was evaluated at isothermal (23 °C) and non-isothermal conditions, in an effort to reproduce standard storage and overseas shipping temperature conditions, respectively. Results show that pH was again the environmental factor with the highest impact on delaying the spoilage of the product. Thereby, a pH value below 2.0 was enough to increase the shelf life of the product for more than 60 days in both isothermal and non-isothermal conditions. The information obtained in the present work could be used by producers and buyers to predict the growth and time for spoilage of Z. rouxii in concentrated grape juice.

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The diffusive relaxation of a colloidal fluid adsorbed in a porous medium depends on many factors, including the concentration and composition of the adsorbed colloidal fluid, the average structure of the porous matrix, and the nature of the colloid-colloid and colloid-substrate interactions. A simple manner to describe these effects is to model the porous medium as a set of spherical particles fixed in space at random positions with prescribed statistical structural properties. Within this model one may describe the relaxation of concentration fluctuations of the adsorbed fluid by simply setting to zero the short-time mobility of one species (the porous matrix) in a theory of the dynamics of equilibrium colloidal mixtures, or by extending such dynamic theory to explicitly consider the porous matrix as a random external field, as recently done in the framework of mode coupling theory [V. Krakoviack, Phys. Rev. Lett. 94, 065703 (2005)]. Here we consider the first approach and employ the self-consistent generalized Langevin equation (SCGLE) theory of the dynamics of equilibrium colloidal mixtures, to describe the dynamics of the mobile component. We focus on the short- and intermediate-time regimes, which we compare with Brownian dynamics simulations involving a binary mixture with screened Coulomb interactions for two models of the average static structure of the matrix: a porous matrix constructed by quenching configurations of an equilibrium mixture in which both species were first equilibrated together, and a preexisting matrix with prescribed average structure, in which we later add the mobile species. We conclude that in both cases, if the correct static structure factors are provided as input, the SCGLE theory correctly predicts the main features of the dynamics of the permeating fluid.

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This paper presents a recently developed theory of colloid dynamics as an alternative approach to the description of phenomena of dynamic arrest in monodisperse colloidal systems. Such theory, referred to as the self-consistent generalized Langevin equation (SCGLE) theory, was devised to describe the tracer and collective diffusion properties of colloidal dispersions in the short- and intermediate-time regimes. Its self-consistent character, however, introduces a nonlinear dynamic feedback, leading to the prediction of dynamic arrest in these systems, similar to that exhibited by the well-established mode coupling theory of the ideal glass transition. The full numerical solution of this self-consistent theory provides in principle a route to the location of the fluid-glass transition in the space of macroscopic parameters of the system, given the interparticle forces (i.e., a nonequilibrium analog of the statistical-thermodynamic prediction of an equilibrium phase diagram). In this paper we focus on the derivation from the same self-consistent theory of the more straightforward route to the location of the fluid-glass transition boundary, consisting of the equation for the nonergodic parameters, whose nonzero values are the signature of the glass state. This allows us to decide if a system, at given macroscopic conditions, is in an ergodic or in a dynamically arrested state, given the microscopic interactions, which enter only through the static structure factor. We present a selection of results that illustrate the concrete application of our theory to model colloidal systems. This involves the comparison of the predictions of our theory with available experimental data for the nonergodic parameters of model dispersions with hard-sphere and with screened Coulomb interactions.

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One of the main elements of the self-consistent generalized Langevin equation (SCGLE) theory of colloid dynamics [Phys. Rev. E 62, 3382 (2000); 72, 031107 (2005)] is the introduction of exact short-time moment conditions in its formulation. The need to previously calculate these exact short-time properties constitutes a practical barrier for its application. In this Brief Report, we report that a simplified version of this theory, in which this short-time information is eliminated, leads to the same results in the intermediate and long-time regimes. Deviations are only observed at short times, and are not qualitatively or quantitatively important. This is illustrated by comparing the two versions of the theory for representative model systems.

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BACKGROUND: Retinoblastoma (RB) is a relatively uncommon tumour in childhood. The incidence of retinoblastoma in Mexico is probably higher than the incidence reported worldwide, however there is not enough information about the characteristics of this illness in Mexico. This report aims to present the results of a multicentre clinical survey of RB in Mexico. METHODS: A retrospective study was carried out on all RB cases treated in 16 institutions during the last six years. The variables analysed were age at diagnosis, sex, affected eyes, treatment modalities, and pathological staging. Overall survival was obtained. RESULTS: The authors analysed 500 cases; age range was 0-182 months. There were 364 unilateral cases (72.8%). Enucleation was performed in 84.9% of the patients. The St Jude's staging was: 7.4% stage I, 52.8% stage II, 18.0% stage III, 11.4% stage IV, 7.2% not evaluated, and 3.2% missing data. Chemotherapy was used in 74.4% of the patients. Disease free survival was 89% at 73 months follow up. CONCLUSIONS: The paper presents a great number of cases and pioneers multicentre studies in paediatric ophthalmology and oncology in this country. Given the great number of patients in advanced stages and the variability on treatment schemes, it is evident that it is mandatory to work in a cooperative group and develop a national early detection programme as well as a treatment protocol which include all specialists involved in the care of patients with RB.

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BACKGROUND: Secondary exposure to lead has been identified as a public health problem since the late 1940s; we investigate the risk of lead exposure among families of radiator repair workers. METHODS: A sample of the wives and children, aged 6 months to 6 years (exposed children) (n = 19), of radiator repair workers and a sample of children whose parents were not occupationally exposed to lead (non-exposed children) (n = 29) were matched for age and residence; their geometric mean blood lead levels are compared. Blood samples were obtained by the finger stick method and environmental dust samples by the wipe method; both were analyzed using a portable anodic stripping voltameter. RESULTS: Dust lead levels were significantly higher in the houses of exposed children (143.8 vs. 3.9 microg/g; P < 0.01). In crude analyses, the highest lead levels were observed among children whose fathers worked in home-based workshops (22.4 microg/dl)(n = 6). Children whose fathers worked in an external workshop (n = 13) also had high levels (14.2 microg/dl) (P < 0.01), while blood lead levels in non-exposed children were significantly lower (5.6 microg/dl)(P < 0.01). The observed differences remained significant after adjustment for age and gender. CONCLUSIONS: This study confirms that children of radiator repair workers are at increased risk of lead exposure and public health interventions are needed to protect them.

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BACKGROUND: The role of single micronutrient deficiencies in the etiology of growth retardation has recently gained attention. However, because multiple micronutrient deficiencies are common in children in developing countries, it is possible that more than one micronutrient may limit growth and, hence, the correction of a single deficiency may not be enough to improve growth substantially. OBJECTIVE: The objective was to evaluate the effect of multiple micronutrient supplementation on the growth of children aged 8-14 mo whose diets were poor in several micronutrients. DESIGN: Children were randomly assigned to 1 of 2 groups. One group received a multiple micronutrient supplement containing the recommended dietary allowance (RDA) or 1.5 times the RDA of vitamins A, D, E, K, C, B-1, B-6, B-12, riboflavin, niacin, biotin, folic acid, and pantothenic acid, and iron, zinc, iodine, copper, manganese, and selenium. The other group received a placebo. Supplements were administered 6 d/wk for an average of 12.2 mo. Body length was measured at baseline and monthly thereafter until the end of supplementation. RESULTS: Supplemented infants initially aged <12 mo had significantly greater length gains than did the placebo group, with a difference of 8.2 mm (length-for-age z score: 0.3) at the end of supplementation. In contrast, differences in length gains between the supplemented and placebo groups initially aged > or =12 mo were not significant. CONCLUSIONS: Micronutrient deficiencies limited the growth of the Mexican infants studied. Improving micronutrient intakes should be a component of interventions to promote growth in infants living in settings where micronutrient intakes are inadequate.

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OBJECTIVE: To assess the prevalence and severity of asthma and allergic diseases in schoolchildren residing in Ciudad Juarez, Chihuahua. MATERIAL AND METHODS: A cross-sectional study was conducted from April 1998 to May 1999, among 6,174 children from 53 schools in Ciudad Juarez, Chihuahua. The method used was the one recommended by the International Study of Asthma and Allergies in Childhood (ISAAC) to determine the prevalence and severity of asthma, rhinitis, and eczema. Parents were asked to answer a standardized questionnaire on current and cumulative prevalence of asthma, rhinitis, and eczema. A sample stratified by level of pollution was selected. RESULTS: The cumulative prevalence of medically diagnosed asthma and wheezing was 6.8% (95% CI 6.2, 7.4) and 20% (95% CI 19.7, 21.8), respectively. The prevalence of wheezing in the last 12 months was higher in the group aged 6-8 years than in those aged 11-14 years (9.7% vs. 5.8%, p < 0.01). The prevalence of medically diagnosed rhinitis was 5.0% (95% CI 4.5, 5.6). The prevalence of medically diagnosed eczema was 4.9% (4.3, 5.4). The prevalence of eczema symptoms in the last 12 months was 12.7% in the 6-8 years group and 13.3% in the 11-14 year group, respectively. Severe symptoms of asthma were significantly higher in the 6-8 years group and during the autumn months. CONCLUSIONS: The prevalence of medically diagnosed and symptomatic asthma was relatively low in comparison with findings from others studies that use similar methods, but the prevalence rates of rhinitis and eczema were higher.

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Significant associations have been reported between particles with a 50% cut-off aerodynamic diameter of 10 mm (PM10) and ozone ambient concentrations, and daily number of deaths from respiratory causes. The aim of the present study was to assess such associations among elderly (> or =65 yrs) residents of Mexico City. Ambient air pollution data were provided by the Metropolitan Monitoring Network. During the study period, the average daily PM10 ranged 23.4-175.3 microg x m(-3), and ozone 1 h daily maximums ranged 39.4-216.7 ppb. Information was compiled on the primary and underlying causes of death. The analyses were conducted separately according to place of death (within or out of a hospital unit) using time-series methodology. The total number of deaths from all respiratory causes and mortality for chronic obstructive pulmonary diseases (COPD) were significantly related to PM10 over different lags: an increase of 10 microg x m(-3) was related to a 2.9% (95% (CI): 0.9-4.9%) increase and to a 4.1% (95% CI: 1.3%-6.9%) increase with a 3-day lag when death occurred out of medical units, respectively. For deaths occurring in medical units, a longer lag and smaller risk estimate was observed. An interactive effect between PM10 and ozone was detected. This study confirms that there is an important impact of PM10 on respiratory morbidity among elderly subjects. It also indicates that accounting for primary and underlying causes of death, and considering place of death may reduce misclassification and provide more accurate estimates of the adverse impact of PM10 on mortality.

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OBJECTIVE: To assess the relationship of < or = 10 microns particles (PM10) and atmospheric ozone concentrations, with the daily number of emergency visits due to asthma and acute respiratory diseases, among children aged under 15, living in Ciudad Juarez, Chihuahua, Mexico. MATERIAL AND METHODS: Between 1998 and 1999, an ecologic study was conducted. Atmospheric data were obtained from the Environmental Protection Agency (EPA), from eight monitoring stations located in Ciudad Juarez, Chihuahua, and EI Paso, Texas. From July 1997 to December 1998, data from emergency room visits for respiratory illness were abstracted from existing medical records of two Mexican Institute of Social Security (IMSS) hospitals in Ciudad Juarez. Diagnoses were classified into two groups: a) asthma, and b) upper respiratory infections (URI), according to the International Classification of Diseases (ICD-9 and/or IDC-10). Statistical analysis was carried out using the Poisson regression time series method. RESULTS: During the study period, the mean 24-hour PM10 level was 34.46 micrograms/m3 (SD = 17.99) and the mean ozone level was 51.60 ppb (SD = 20.70). The model shows that an increase of 20 micrograms/m3 in the mean 24-hour exposure to PM10 was related to an increase of 4.97% (95% CI 0.97-9.13) in emergency visits for asthma, with a 5-day lag, as well as to an increase of 9% (95% CI 1.8-16.8) when a cumulative 5-day exposure was considered. URI increased 2.95% as a cause of emergency room visits, for each 20 micrograms/m3 increase in the mean 24-hour exposure to PM10. The impact of PM10 on emergency visits for asthma was greater on days with ozone ambient levels exceeded 49 ppb (median value). CONCLUSIONS: A positive association was found between environmental PM10 and ozone concentrations and the daily number of emergency room visits due to asthma and acute respiratory diseases, even with levels lower than the Mexican standard levels. Also, a synergic effect between PM10 and O3 was found.

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