Pulse electrodeposition of CuSbS2 thin films: Role of Cu/Sb precursor ratio on the phase formation and its performance as photocathode for hydrogen evolution§.

In this paper, we outline the development of stoichiometric chalcostibite, CuSbS2 thin films, from a single bath by pulse electrodeposition for its application as a photocathode in photoelectrochemical cells (PEC). The Cu/Sb precursor molar ratio of the deposition bath was varied to obtain stoichiometric CuSbS2 thin films. The optimized deposition and dissolution potentials were -0.72 V and -0.1 V vs saturated calomel electrode, respectively. The formation of CuSbS2 was analyzed using different characterization tools. X-ray diffraction and Raman results showed the formation of the pure chalcostibite phase from a precursor bath with molar ratio Cu/Sb = 0.41. The heterostructure CuSbS2/CdS/Pt was tested as a photocathode in the PEC. The energy positions of the conduction and valence bands were estimated from the Mott Schottky plots. The conduction band and valence band offset of CuSbS2/CdS heterojunction were 0.1 eV and 1.04 eV, respectively. The electric field created in the junction reduced the recombination of the electron/hole pairs and improved charge transfer in the interface. The heterostructure CuSbS2/CdS/Pt demonstrated an improved photocurrent density of 3.4 mA cm-2 at 0 V vs reversible hydrogen electrode. The PEC efficiency obtained from the CuSbS2/CdS heterojunction was 0.56 %. Therefore, we demonstrated the feasibility of an inexpensive technique like electrodeposition for the development of an efficient earth-abundant photocathode.

Changes in air quality in Mexico City, London and Delhi in response to various stages and levels of lockdowns and easing of restrictions during COVID-19 pandemic.

The impacts of COVID-19 lockdown restrictions have provided a valuable global experiment into the extent of improvements in air quality possible with reductions in vehicle movements. Mexico City, London and Delhi all share the problem of air quality failing WHO guideline limits, each with unique situations and influencing factors. We determine, discuss and compare the air quality changes across these cities during the COVID-19, to understand how the findings may support future improvements in their air quality and associated health of citizens. We analysed ground-level PM10, PM2.5, NO2, O3 and CO changes in each city for the period 1st January to August 31, 2020 under different phases of lockdown, with respect to daily average concentrations over the same period for 2017 to 2019. We found major reductions in PM10, PM2.5, NO2 and CO across the three cities for the lockdown phases and increases in O3 in London and Mexico City but not Delhi. The differences were due to the O3 production criteria across the cities, for Delhi production depends on the VOC-limited photochemical regime. Levels of reductions were commensurate with the degree of lockdown. In Mexico City, the greatest reduction in measured concentration was in CO in the initial lockdown phase (40%), in London the greatest decrease was for NO2 in the later part of the lockdown (49%), and in Delhi the greatest decrease was in PM10, and PM2.5 in the initial lockdown phase (61% and 50%, respectively). Reduction in pollutant concentrations agreed with reductions in vehicle movements. In the initial lockdown phase vehicle movements reduced by up to 59% in Mexico City and 63% in London. The cities demonstrated a range of air quality changes in their differing geographical areas and land use types. Local meteorology and pollution events, such as forest fires, also impacted the results.

Incontinencia urinaria de urgencia en mujeres adultas: ¿Qué tratamientos ofrecer en APS? / Emergency Urinary Incontinence in Adult Women: what treatments do we offer at PHC?

La incontinencia urinaria de urgencia corresponde a la pérdida involuntaria de orina, cuya causa es presumida multifactorial: hiperactividad del detrusor, hipersensibilidad vesical y distensibilidad reducida del detrusor. Esta patología es bastante frecuente tanto en Chile como en el mundo, con una prevalencia local entre 10% y 15%, a su vez genera un gran impacto en el bienestar físico, mental y socioeconómico del paciente. El diagnóstico es clínico, con apoyo en el uroanálisis y su tratamiento de primera línea puede ser realizado en APS. En cuanto al tratamiento existen tanto terapias no farmacológicas como farmacológicas; correspondiendo las técnicas de reentrenamiento vesical, los cambios de estilo de vida y los fármacos anticolinérgicos a tratamientos efectivos de primera línea. Existen, además, otros fármacos que pueden ser utilizados para el tratamiento de la IUU, cuya evidencia será igualmente revisada en este artículo.

Urge incontinence is defined as an involuntary leakage of urine, presumably with a multifactorial cause: detrusor overactivity, bladder hypersensibility and a reduced bladder compliance. It's a common disease worldwide, with local studies reporting a prevalence around 10-15%, causing a great impact in the physical, mental and socioeconomic well-being of the affected patients. Diagnosis is mainly based on the clinical history, supporting it with laboratory tests to rule out other conditions, and uncomplicated cases can be treated and followed in a primary care setting. There are pharmacologic and non-pharmacologic therapies, being healthy lifestyles changes, bladder retraining programs and anticholinergic drugs the first line of treatment. Additional pharmacologic treatments will be revised in this article.

A simple method to evaluate groundwater vulnerability in urbanizing agricultural regions.

A methodology to evaluate groundwater vulnerability was developed and tested in a case study in the Central Valleys of the state of Oaxaca, Mexico, a region known for intensive agricultural activities and poor water management policies. An analysis was conducted to create and evaluate scenarios reflecting anthropogenic and natural stressors on groundwater using an analytical hierarchy process (AHP) and geographic information systems. Uncertainty in the vulnerability model was assessed using a Monte Carlo analysis. Five indices (abstraction (Abs), pollution (Po), runoff (Ru), groundwater recharge (Re), and marginalization (Ma)) were selected after an evaluation of the effects of population growth, climatology, hydrogeological features, and social marginalization on access to groundwater. Abstraction, pollution, and recharge rates are the main drivers of groundwater vulnerability, accounting for 87% of the vulnerability. The analysis revealed that the proposed model generates consistent results and contains low uncertainty. It also showed that more than 50% of the region's groundwater is moderately, and the vulnerability has become increasingly with abstraction, reduced recharge, and pollution (the most sensitive indices), indicating that groundwater in the Central Valleys is under great stress. Pollution and abstraction of groundwater resources are expected to rise in the more vulnerable areas, which will increase water crises and reduce access to water in rural communities. The approach and the indicators establish a baseline for the management and protection of water resources in developing countries where high-resolution data are lacking.

Study of the Huntington's disease IT-15 gene in different ethnic groups in Ecuador.

This study aims to establish the current state of the IT-15 (HTT) gene in different Ecuadorian ethnic groups and patients by determining CAG triplet repeats, compared with the ethnicity of individuals. A total of 412 individuals were studied using nested polymerase chain reaction and Sanger sequencing: 75 individuals were indigenous (Kichwas), 211 mestizos, and 65 Afro-Ecuadorians. We included 31 patients who were clinically diagnosed with Huntington's disease (HD) and relatives of the affected patients (n = 30). Moreover, we correlated the presence of HD in Ecuadorian patients with 46 genetic ancestry-informative insertion-deletion polymorphic markers. We found that 77.20% had <28 CAG repetitions, 18.80% had mutable alleles, 2.27% had incomplete penetrance, and 1.70% reflected >39 repetitions. The average of CAG repetitions was 24 ± 3 for indigenous people; 28 ± 2 for mestizos; and 24 ± 3.2 repetitions for the Afro-Ecuadorians. The ancestral component showed that the main ancestry corresponded to Native Americans (0.873) and European ascendants (0.145), Africans were less represented in the evaluated population (0.018). There was a significant difference between the number of CAG repeats in mestizos and indigenous people (P < .01), suggesting that the Ecuadorian mestizo population has a risk factor for the gene mutation.

The anti-estrogenic activity of indole-3-carbinol in neonatal rat osteoblasts is associated with the estrogen receptor antagonist 2-hydroxyestradiol.

PURPOSE: To gain new insight into the roles of cruciferous vegetable-derived bioactive phytochemicals in bone cells, we investigated the effects of indole-3-carbinol (I3C) on cell proliferation and differentiation in estradiol (E2)-exposed calvarial osteoblasts that were obtained from neonatal rats. METHODS: Osteoblast activity was assessed by analyzing cellular DNA, cell-associated osteocalcin (OC) levels and alkaline phosphatase (AP) activity. We also examined [(3)H]-estrone (E1) metabolism and estrogen-agonistic and estrogen-antagonistic activities of 2-hydroxy (OH) E1 and 2-OHE2 and their capacity to displace [(3)H]-E2 at ER binding sites using competition studies. RESULTS: I3C did not affect on cellular DNA, OC levels or AP activity. However, I3C completely inhibited E2-induced increases in cell proliferation and differentiation in neonatal rat osteoblasts. Metabolic studies demonstrated that I3C promoted the conversion of [(3)H]-E1 to 2-OHE1 and 2-OHE2 and those higher rates of conversion (twofold-threefold) were archived when a higher dose of I3C was applied. Proliferation and differentiation studies showed that 2-OHE2 but not 2-OHE1 inhibited E2-induced increases in cell proliferation and differentiation via an ER-mediated mechanism. Likewise, Esr1 was expressed at high level than Esr2. 2-OHE1 showed no activity or affinity for ER. CONCLUSIONS: This study is the first to show that a bioactive compound derived from cruciferous vegetables, I3C, abolishes the E2-mediated stimulation of cell activities including, proliferation and differentiation, in rat osteoblasts and increases the 2-hydroxylation of E1, resulting in the formation of inactive and anti-estrogenic metabolites. These results suggest that in neonatal rat osteoblasts, the anti-estrogenic effect of I3C is mediated by 2-OHE2 through ER-α.

[Prevalence of hip, femur and knee fractures at the High Specialty Medical Unit, Hospital de Traumatología y Ortopedia "Lomas Verdes", Instituto Mexicano del Seguro Social]. / Prevalencia de fracturas de cadera, fémur y rodilla en la Unidad Médica de Alta Especialidad Hospital de Traumatología y Ortopedia "Lomas Verdes" del Instituto Mexicano del Seguro Social.

BACKGROUND: Lower limb fractures are more frequent among older patients with osteopenia after a low energy fall and/or among young patients who sustain a high energy trauma. The prevalence of hip, femur and knee fractures at the High Specialty Medical Unit, Hospital de Traumatología y Ortopedia "Lomas Verdes" is unknown. MATERIAL AND METHODS: Cross-sectional study, descriptive and retrospective design. Cases with low extremity fractures treated from January 1st, 2012 to December 31st, 2013 at the Hip, Femur and Knee Service, High Specialty Medical Unit, Hospital de Traumatología y Ortopedia "Lomas Verdes", were reviewed. RESULTS: Most patients (52.2%) were females; 64.1% of patients were over 60 years of age. Fracture distribution according to the segment involved was as follows: 73.4% (n = 1,327) were femur fractures, 13.5% (n = 244) tibial plateau fractures, and 13.2% (n = 238) patellar fractures. 66.8% (n = 1,209) of patients had a long hospital stay (more than 10 days). According to the anatomical location of fractures, transtrochanteric fractures (49.1%) were the most frequent ones, followed by patellar fractures (13.2%), and femur shaft fractures (12.7%). CONCLUSIONS: The prevalence of lower limb fractures at our hospital corresponds to what has been reported internationally.

Allergy and acute leukaemia in children with Down syndrome: a population study. Report from the Mexican inter-institutional group for the identification of the causes of childhood leukaemia.

BACKGROUND: Allergies have been described as protective factors against the development of childhood acute leukaemia (AL). Our objective was to investigate the associations between allergy history and the development of AL and acute lymphoblastic leukaemia (ALL) in children with Down syndrome (DS). METHODS: A case-control study was performed in Mexico City. The cases (n=97) were diagnosed at nine public hospitals, and the controls (n=222) were recruited at institutions for children with DS. Odds ratios (OR) were calculated. RESULTS: Asthma was positively associated with AL development (OR=4.18; 95% confidence interval (CI): 1.47-11.87), whereas skin allergies were negatively associated (OR=0.42; 95% CI: 0.20-0.91). CONCLUSION: Our findings suggest that allergies and AL in children with DS share biological and immune mechanisms. To our knowledge, this is the first study reporting associations between allergies and AL in children with DS.

Obtaining Ca(H2PO4)(2)·H2O, monocalcium phosphate monohydrate, via monetite from brushite by using sonication.

Brushite was synthesized by precipitation of calcium chloride (CaCl(2)) and sodium phosphate monobasic (Na(2)HPO(4)) dried in vacuum and monetite was obtained from this brushite by sonication with a frequency of 90kHz at 500W for 90min. Monetite itself was also transformed in Ca(H(2)PO(4))(2)·H(2)O, monocalcium phosphate monohydrate (MCPM), by sonication with a frequency of 90kHz at 500W for 60min followed by lyophilization. The MCPM was sonicated and lyophilized by three times more until reach over 240min, but any other phase transformation was observed. All these phase transformations were analyzed by X-ray diffraction (XRD) and infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated a grain size of about 200nm in all the samples. The morphology observed was a corn-flake-like grain for brushite, a pseudo-needle-like grains for monetite, and lamellar-like grains for MCPM.

IFN-g response to vaccination against tuberculosis in dairy heifers under commercial settings.

The purpose was to determine IFN-g release as a response to vaccination against tuberculosis in dairy heifers under commercial settings. Four-hundred pregnant heifers from ten herds were randomly allocated into four groups: (1) unvaccinated, (2) BCG vaccinated, (3) BCG vaccinated plus a CFPP400 µg+polygen boost, and (4) BCG vaccinated plus a CFP200 µg+polygen boost, under a completely randomized blocks design. A dose of 106CFU of BCG was delivered SC in the neck, then blood samples were taken at days 0, 30, 120, 210, 300 and 720 to estimate IFN-g release in response to bovine-PPD antigen. No significant difference (P > 0.05) was observed in IFN-g release between groups at days 0 and 120. At days 30 and 210, vaccinated groups show higher IFN-g release than the control group but only difference of group 3 was significant (P < 0.05). At day 300, group 1 showed significantly higher IFN-g release. No significant difference was observed at day 720. Using IFN-g release as a surrogate for vaccine efficacy, BCG plus a boost with CFP or CFPP combined with an adjuvant that improves cellular immune response has the potential to protect cattle against tuberculosis for moderate periods of time in vaccinated cattle under commercial settings.

The role of sulphate reduction on the reductive S decolorization of the azo dye reactive orange 14.

The aim of this study was to investigate the impact of a broad range of sulphate concentrations (0-10g SO4(-2) L(-1)) on the reduction of an azo dye (reactive orange 14 (RO14)) by an anaerobic sludge. An increase in the sulphate concentration generally stimulated the reduction of RO14 by sludge incubations supplemented with glucose, acetate or propionate as electron donor. Sulphate and azo dye reductions took place simultaneously in all incubations. However, there was a decrease on the rate of decolorization when sulphate was supplied at 10g SO4(-2) L(-1). Abiotic incubations at different sulphide concentrations (0-2.5 g sulphide L(-1)) promoted very poor reduction of RO14. However, addition of riboflavin (20 microM), as a redox mediator, accelerated the reduction of RO14 up to 44-fold compared to a control lacking the catalyst. Our results indicate that sulphate-reduction may significantly contribute to the reduction of azo dyes both by biological mechanisms and by abiotic reductions implicating sulphide as an electron donor. The contribution of abiotic decolorization by sulphide, however, was only significant when a proper redox mediator was included. Our results also revealed that sulphate-reduction can out-compete with azo reduction at high sulphate concentrations leading to a poor decolorising performance when no sufficient reducing capacity is available.

[Identification of the patient with acute severe pancreatitis. A prospective, comparative study of the Ranson and the Salvador Zubirán National Institute of Nutrition criteria]. / La identificación del enfermo con pancreatitis aguda grave. Un estudio prospectivo, comparativo entre los criterios de Ranson y los del Instituto Nacional de la Nutrición Salvador Zubirán.

Early detection of severe acute pancreatitis could represent a formidable task for the clinician with limited resources. We have previously proposed a series of parameters that can identify patients with severe acute pancreatitis. The aim of this prospective study was to compare Ranson criteria with those previously described by the authors (INNSZ criteria) in 78 patients with acute pancreatitis. Sensitivity, specificity, positive and negative predictive values and accuracy were similar in both scores. We found a good correlation (r = 0.65, p < 0.001) and agreement (z = 5.0, Kappa 0.69, p < 0.001) between Ranson and INNSZ criteria. Our results allow us to propose INNSZ severity criteria as an easy and inexpensive alternative in the evaluation of patients with acute pancreatitis.

Asociación de absceso cerebral y cardiopatía congénita / Association of cerebral abscess and congenital cardiopathy

Analiza que el absceso cerebral constituye una entidad relevante entre las causas de mortalidad en países en desarrollo. En el Hospital de Niños Baca Ortiz, del Ecuador se estudia 30 casos de absceso cerebral encontrándose 8 pacientes portadores de cardiopatía congénita para determinar su influencia, comportamiento, factores añadidos y se demuestra la importancia del diagnóstico y tratamiento precoz de cardiopatías congénitas, así como la utilización de profilaxis.

5alpha-reduction of norethisterone enhances its binding affinity for androgen receptors but diminishes its androgenic potency.

Norethisterone (NET), a 19-nor synthetic progestin, undergoes enzyme-mediated 5alpha-reduction and exerts potent androgenic effects in target organs. To investigate its mode of androgenic action we examined, in a comparative manner, the in vitro metabolism of NET and testosterone (T), as well as the binding affinities to androgen receptors (AR) and the androgenic potency of NET, T, and their 5alpha-reduced derivatives. Bioconversion of [3H]-NET and [3H]-T was studied in rat prostate homogenates, AR binding affinity was assessed in rat ventral prostates using [3H]-mibolerone as the radioligand, and the androgenic potency was evaluated by the increase of beta-glucuronidase activity in the mouse kidney, and by the growth of accessory sex organs in castrated male rats. The results demonstrated that 5alpha-NET displayed a higher AR binding affinity but a significantly lower androgenic potency than unchanged NET. The bioconversion studies indicated that the metabolism of NET was similar to that of T, although to a lesser extent, thus ruling out the possibility that the synthetic progestin metabolizes rapidly into less active derivatives. To investigate the nature of the paradoxical effect of 5alpha-reduction upon the NET molecule, the interaction with AR and the androgenic potency of T, 19-nortestosterone (19norT), 17alpha-ethynyl testosterone (ET) and their 5alpha-reduced derivatives were examined. The results of AR binding studies revealed that 5alpha-reduction of T and ET significantly enhanced their affinities, and that the 5alpha-derivative of 19norT displayed a similar binding affinity to that exhibited by 19norT. In terms of biological activity, the results showed that 5alpha-reduction of T and 19norT significantly increased their androgenic potency, whereas 5alpha-reduction of ET resulted in a significant diminution of its androgenicity in a manner similar to that observed with the 5alpha-reduction of NET. When NET and 19norT were simultaneously administered with 5alpha-dihydrotestosterone they exhibited a potent synandrogenic activity, an effect that was cancelled by their 5alpha-reduction. Interestingly, ET displayed an antiandrogenic activity, an effect that was also suppressed by its 5alpha-reduction. The overall results demonstrated a distinctive, paradoxical effect of 5alpha-reduction upon the NET molecule, which was different from that seen in naturally occurring androgens, and which suggests that the presence of the 17alpha-ethynyl group plays a key role in this phenomenon. The data provided further evidence that the metabolism of synthetic contraceptive progestins modulates the expression of their hormone-like actions.

Steroid 5 alpha-reductase activity in the harderian glands of male and female Syrian hamster (Mesocricetus auratus).

The activity of the enzyme steroid 5 alpha-reductase in Harderian glands of adult syrian hamsters was assessed by measuring the conversion of testosterone (T) to 5 alpha-dihydrotestosterone (DHT). The optimal conditions for this reaction were determined in vitro using whole gland homogenates and [3H]testosterone as substrate. Enzyme activity was maximal at pH 5.5. The Michaelis-Menten constant of the Harderian enzyme for T was 4.6 +/- 1.2 x 10(-6) M in females and 4.2 +/- 0.39 x 10(-6) M in males, estimated by Eadie-Hofstee plots. On the basis of relative maximum velocity values, there was 9 or 10 times more 5 alpha-reductase in females (2.8 +/- 0.67 nmol/mg protein/hr) than in males (0.289 +/- 0.029 nmol/mg protein/hr). Consistently, glands of intact male hamsters had lower 5 alpha-reductase activities than those of females. Castration of males significantly increased the enzymatic activity, which within 4 weeks reached female-like values. The levels of 5 alpha-reductase mRNA also increased with castration. There was a direct correlation between activity and mRNA levels of the enzyme in castrated male glands. Further, the administration of T or DHT to ovariectomized hamsters led to intact male values in the enzymatic activity of the gland. The sex differences in 5 alpha-reductase activity may be of relevance to the differential regulation exerted by androgen upon the physiology of male and female glands. The results are consistent with the view that 5 alpha-dihydrotestosterone is the active androgen in the Harderian gland.

[Serum macroamylase in a subject with non-Hodgkin's lymphoma]. / Macroamilasemia en un sujeto con linfoma no-Hodgkin.

Macroamylasemia (MA) is a rare condition characterized by an active macromolecular complex formed by normal amylase with abnormal proteins; to our knowledge, it has not been previously described in Mexico. The size of the macromolecular complex precludes its renal excretion; thus MA is characterized by high levels of amylase in serum with normal amylasuria. We report a 53-year-old male with abdominal pain and hyperamylasemia who was erroneously diagnosed as pancreatitis. Amylase in urine was normal and a protein electrophoresis demonstrated hyperglobulinemia. Several months after the initial work-up, the diagnosis of non-Hodgkin's lymphoma was established. Serum pancreatic amylase was again found elevated with normal urinary amylase. Precipitation of amylase with polyethylene-glycol was of 81% (normal: less than 70%). This established the diagnosis of MA associated to non-Hodgkin's lymphoma. After chemotherapy, the abnormal macroamylasemia and hyperglobulinemia disappeared.

[Systolic stress in mitral stenosis]. / Estrés sistólico en la estenosis mitral.

Left ventricular systolic stress was studied in nineteen patients with mitral stenosis, twelve in sinus rhythm and seven in atrial fibrillation. Left ventricular dimensions and volumes and septal and posterior wall thickness were measured by means of M and two bidimensional echocardiography at rest and during isometric exercise. Expulsive indices: fractional shortening, ejection fraction and mean circumferential shortening rate were calculated. Ventricular mass, meridional stress and several end-systolic stress or pressure/volume relationships were estimated. Patients with atrial fibrillation were older and had systolic dysfunction: greater end-systolic volumes and depression of both expulsive fractions and some of the end-systolic indices. Preload and wall thickness were normal. Patients with atrial fibrillation showed higher ventricular stress as a consequence of greater ventricular dimensions. Ejection fraction correlates directly with mitral valve area and inversely with inotropic state and heart rate. It is concluded that systolic dysfunction in mitral stenosis is multifactorial. The most important determinants of the abnormality are heart rate and inotropic state. The study did not show any primary abnormality of afterload or hypotrophy of the left ventricle.