ABSTRACT Introduction: based on the report of a cluster of pneumonia cases of unknown etiology on December 31, 2019 in Wuhan, China, the World Health Organization declared the outbreak to be a public health emergency of international concern; COVID-19 became a pandemic. The process of collecting the sample in the detection of SARS-CoV-2 represents one of the initial and highly relevant stages for carrying out an efficient and robust diagnosis. Objective: to characterize aspects related to the detection of SARS-CoV-2 and the taking of samples in the Province of Villa Clara. Methods: a descriptive, observational, retrospective investigation was carried out with the objective of characterizing aspects related to the detection of SARS-CoV-2 and the taking of samples in the Province of Villa Clara from the 157 confirmed cases with the disease in the period of study. Results: more than half of the cases were taken for bilateral nasal exudate, with a mean threshold cycle of 27.9, with a standard deviation of 7.1. 53.3% of the means of transport corresponded to the Sensure Biotech brand; this type of transport medium was the one with the most samples, with a threshold cycle below 20. Conclusions: the sample with the highest positivity was the bilateral nasal exudate, which coincides with international authors. Of the means of transport evaluated, Sensure Biotech was the one that offered the best results. In the case of asymptomatic patients, the sample that presented the best results was bilateral nasal exudate.

RESUMEN Introducción: a partir del informe de un grupo de casos de neumonía con etiología desconocida el 31 de diciembre de 2019 en Wuhan, China, la Organización Mundial de la Salud declaró que el brote iniciado era una emergencia de salud pública de importancia internacional; la COVID-19 se convertía en una pandemia. El proceso de la recolección de la muestra en la detección del SARS-CoV-2 representa una de las etapas iniciales y de gran relevancia para la realización de un diagnóstico eficiente y robusto. Objetivo: caracterizar aspectos relacionados con la detección del SARS-CoV-2 y la toma de muestra en la Provincia de Villa Clara. Métodos: se realizó una investigación descriptiva, observacional, retrospectiva con el objetivo de caracterizar aspectos relacionados con la detección del SARS-CoV-2 y la toma de muestra en la Provincia de Villa Clara a los 157 casos confirmados con la enfermedad en el período de estudio. Resultados: más de la mitad de los casos se tomaron por exudado nasal bilateral, con un ciclo umbral medio de 27,9, con una desviación estándar de 7,1. El 53,3% de los medios de transporte correspondieron a la marca de Sensure Biotech; este tipo de medio de transporte fue el que tuvo más muestras, con un ciclo umbral por debajo de 20. Conclusiones: la muestra con mayor positividad fue el exudado nasal bilateral, lo que coincide con autores internacionales. De los medios de transporte evaluados fue Sensure Biotech el que ofreció mejores resultados. En el caso de los pacientes asintomáticos la muestra que mejores resultados presentó fue el exudado nasal bilateral.

RESUMEN Introducción: La rehospitalización temprana en unidades de salud mental (USM) es la necesidad de hospitalización de un paciente en los primeros 30 días tras el alta, principalmente por descompensación recurrente de su enfermedad mental. Este fenómeno se relaciona con un peor pronóstico y tiene impacto en el entorno familiar, social y laboral. El ausentismo laboral y las estancias hospitalarias adicionales son gastos para el sistema de salud y de empleo que han hecho de la rehospitalización un fenómeno de especial interés. El presente estudio se llevó a cabo con el objetivo de explorar los factores asociados con el reingreso de los pacientes con enfermedad psiquiátrica atendidos en 2 USM en 2018, así como aquellos modificables que actúen como protección contra esta condición. Métodos: Estudio observacional descriptivo con componente analítico de tipo casos y controles en 2 USM de distintas ciudades de Colombia. Se obtuvo información por medio de una ficha de recolección de datos tomados de los registros de historias clínicas de los pacientes que ingresaron entre el 1 de enero y el 31 de diciembre de 2018. La recolección de datos se hizo del 20 de febrero al 27 de mayo de 2019. Compusieron la muestra todos los pacientes que cumplían los criterios de reingreso temprano en ambas instituciones. El grupo de estudio estuvo conformado por 113 pacientes: 28 casos y 85 controles, emparejados por las variables edad, sexo, lugar de hospitalización y diagnóstico. Resultados: En las 2 USM hospitalarias, los diagnósticos encontrados fueron: depresión (15,5%), trastorno afectivo bipolar (33,1%) y esquizofrenia (37,3%); en Bogotá la más prevalente fue la depresión (31,1%) y en Tunja, la esquizofrenia (44,8%). Para ambas instituciones, el factor que más se asocia con el reingreso es el consumo de alcohol, pero otras variables de tratamiento, núcleo familiar e intervención individual también se asociaron con mayor probabilidad de reingreso temprano. Conclusiones: Se pudo demostrar que el uso de antipsicóticos atípicos y/o de depósito, las hospitalizaciones de más de 15 días y la prescripción de menos de 3 medicamentos al alta disminuyen el número de reingresos tempranos en las USM.

ABSTRACT Introduction: Early rehospitalisation in mental health units (SMHUs) is when a patient needs to be readmitted in the first 30 days after receiving discharge, and is mainly due to recurrent decompensation of their mental illness. This phenomenon is related to a worse prognosis and has an impact on the family, social and work environment. Absenteeism from work and additional hospital time are expenses for the health and employment system which have made rehospitalisation a phenomenon of special interest. The present study was carried out with the objective of exploring the factors associated with the readmission of patients with psychiatric illnesses treated in two MHUs during 2018, as well as those modifiable factors that act as protection for this condition. Methods: Observational, descriptive study with analytical component of cases and controls in two MHUs in different cities of Colombia. Information was obtained by collecting data from the medical records of patients who were admitted between 1 January 2018 and 31 December 2018. The data were collected between 20 February and 27 May 2019. The sample was composed of all the patients who met the criteria for early readmission in both institutions. The study group consisted of 113 patients: (28 cases and 85 controls), matched by the variables: age, sex, place of hospitalisation and diagnosis. Results: In the two hospital MHUs the diagnoses found were: depression (15.5%), bipolar affective disorder (33.1%) and schizophrenia (37.3%). In Bogotá, the most prevalent was depression (31.1%) and, in Tunja, it was schizophrenia (44.8%). For both institutions, the factor most associated with readmission was alcohol consumption, but other variables of treatment, family nucleus, and individual intervention were also associated with a greater probability of early readmission. Conclusions: It was possible to demonstrate that the use of atypical and/or depot antipsychotics, hospitalisations longer than 15 days, and prescriptions of less than three drugs at discharge, reduce the number of early readmissions to MHUs.

RESUMO Introdução: Síndrome de Guillain-Barré (SGB), uma polirradiculoneuropatia aguda que ocorre devido a uma resposta inflamatória anormal no sistema nervoso periférico, é caracterizada clinicamente por paralisia flácida aguda e arreflexia, com ou sem sintomas sensitivos. Essa síndrome pode deixar sequelas incapacitantes ou até ameaçar a vida. Objetivo: Apresentar os aspectos clínicos e epidemiológicos da SGB em pacientes internados em um hospital terciário do Distrito Federal, no período de janeiro/2013 a junho/2019. Métodos: Estudo observacional, transversal e retrospectivo, no qual pacientes com diagnóstico de polirradiculoneuropatia desmielinizante inflamatória aguda, neuropatia axonal motora aguda ou neuropatia axonal sensitivo motora aguda a partir dos achados eletroneuromiográficos foram selecionados e seus dados clínicos coletados retrospectivamente em seus prontuários. Resultados: Um total de 100 pacientes (63 homens e 37 mulheres; proporção de 1,7:1), com idades entre 2–86 anos (média, 36,4 anos), foram incluídos. A taxa média anual de incidência de SGB foi de 0,54 casos/100.000 habitantes, com 52 e 49% dos casos ocorrendo entre outubro e março (período chuvoso) e entre abril e setembro (período seco), respectivamente. A proporção de pacientes que apresentaram cada variante de SGB foi a seguinte: formas desmielinizantes, 57%; formas axonais, 39%; e indeterminado, 4%. A duração média da hospitalização foi de 8‒15 dias para a maioria dos pacientes (38%). Durante a hospitalização, 14% dos pacientes necessitaram de ventilação mecânica e 20% apresentaram complicações infecciosas. Conclusão: Os resultados indicam aumento na incidência de GBS durante a estação chuvosa. Além disso, não observamos a distribuição bimodal típica em relação à idade de início.

Abstract Background: Guillain-Barré syndrome (GBS), an acute polyradiculoneuropathy that occurs because of an abnormal inflammatory response in the peripheral nervous system, is clinically characterized by acute flaccid paresis and areflexia with or without sensory symptoms. This syndrome can lead to disabling or even life-threatening sequelae. Objective: This study aimed to present the clinical and epidemiological aspects of GBS in patients admitted to a tertiary-level hospital in the Federal District between January 2013 and June 2019. Methods: In this observational, cross-sectional and retrospective study, medical records of patients diagnosed with acute inflammatory demyelinating polyradiculoneuropathy, acute motor axonal neuropathy or acute axonal motor-sensitive neuropathy based on electromyographic findings were included, and clinical data were collected retrospectively. Results: A total of 100 patients (63 males and 37 females; ratio, 1.7:1) aged 2–86 years (mean, 36.4 years) were included. The mean annual incidence rate of GBS was 0.54 cases/100,000 inhabitants, with 52 and 49% of the cases occurring between October and March (rainy season) and between April and September (dry season), respectively. The proportions of patients showing each GBS variant were as follows: demyelinating forms, 57%; axonal forms, 39%; and undetermined, 4%. The mean duration of hospitalization was 8–15 days for most patients (38%). During hospitalization, 14% of the patients required mechanical ventilation and 20% experienced infectious complications. Conclusion: The findings indicate that there was an increase in the incidence of GBS during the rainy season. Moreover, we did not observe the typical bimodal distribution regarding age at onset.

ABSTRACT Introduction: bacillary dysentery was described in the Ebers papyri 2000 years before our era by Hippocrates, Father of Medicine, in the 5th century. It is one of the most important causes of medical care in the presence of unfavorable hygienic conditions. Objective: to characterize the antimicrobial resistance of Shigella strains isolated in children attended at the University Pediatric Hospital “José Luis Miranda” in the period from January to December 2018. Methods: a cross-sectional descriptive study was performed. The 25 Shigella strains selected by non-probabilistic purposive sampling were used for the investigation. Descriptive statistical methods were used. The ethical norms established in the context and the bioethical principles of autonomy, beneficence, non-maleficence and justice were taken into account. Results: the most representative serogroup in the sample was Shigella sonnei, with 19 strains, for 76% of the total number of isolates in the year. 84% of the strains were Shigella sonnei. Eighty-four percent of the strains were resistant to nalidixic acid. It was found that 16% of the isolated strains were resistant to three or more antibiotics, therefore, they were considered multidrug resistant. Conclusions: ciprofloxacin was sensitive to all the strains under study. Multidrug resistance was found in a small, although not ligible, percentage of the samples, which highlights the need to maintain active surveillance of this health problem.

RESUMEN Introducción: la disentería bacilar fue descrita en los papiros de Ebers 2000 años antes de nuestra era por Hipócrates, Padre de la Medicina, en el siglo V. Es una de las causas más importantes de atención médica en presencia de condiciones higiénicas desfavorables. Objetivo: caracterizar la resistencia antimicrobiana de cepas de Shigella aisladas en niños atendidos en el Hospital Pediátrico Universitario “José Luis Miranda” en el período de enero a diciembre de 2018. Métodos: se realizó un estudio descriptivo transversal. Se utilizaron para la investigación las 25 cepas de Shigella seleccionadas por un muestreo no probabilístico intencionado. Se emplearon métodos de estadística descriptiva. Se tuvieron presentes las normas éticas establecidas en el contexto y los principios bioéticos de autonomía, beneficencia, no maleficencia y justicia. Resultados: el serogrupo más representativo en la muestra fue Shigella sonnei, con 19 cepas, para un 76% del total de aislamientos en el año. El 84% de las cepas eran resistentes al ácido nalidíxico. Se pudo constatar que el 16% de las cepas aisladas presentaba resistencia a tres o más antibióticos, por tanto, fueron consideradas multidrogorresistentes. Conclusiones: el ciprofloxacino fue sensible ante la totalidad de las cepas de estudio. Se constató multidrogorresistencia en un pequeño, aunque no despreciable, por ciento de las muestras, lo que alerta la necesidad de mantener una activa vigilancia en este problema de salud.

Molecular-typing can help in unraveling epidemiological scenarios and improvement for disease control strategies. A literature review of Mycobacterium tuberculosis transmission in Brazil through genotyping on 56 studies published from 1996-2019 was performed. The clustering rate for mycobacterial interspersed repetitive units - variable tandem repeats (MIRU-VNTR) of 1,613 isolates were: 73%, 33% and 28% based on 12, 15 and 24-loci, respectively; while for RFLP-IS6110 were: 84% among prison population in Rio de Janeiro, 69% among multidrug-resistant isolates in Rio Grande do Sul, and 56.2% in general population in São Paulo. These findings could improve tuberculosis (TB) surveillance and set up a solid basis to build a database of Mycobacterium genomes.

ABSTRACT Introduction: invasive mycoses caused by Candida spp remain the most diagnosed in neonatal, pediatric and adult patients hospitalized in intensive care rooms at the provincial level. Objective: to identify the main type of sample by age group and Candida species by type of sample in neonates and children under 18 years. Methods: a descriptive, cross-sectional study on the isolates of Candida spp in blood cultures, urine cultures, cerebrospinal fluid, endotracheal tube and catheter tip obtained from neonatal, pediatric and adult patients hospitalized in serious care rooms in the five provincial hospitals of Villa Clara between on January 1, 2018 until August 31, 2019. The sample was 114 positive isolates. Absolute, relative, percent, and statistical frequency distributions were obtained as Pearson's chi-square. Results: adults provided higher numbers of positive isolates, followed by neonates and pediatric age, mainly in 2018. Blood samples, followed by urine samples in neonates and pediatric patients were the most diagnosed; in adults it was the other way around. In neonates Candida tropicalis and Candida spp were the most isolated species, without statistical significance, in pediatric patients were Candida spp and Candida krusei, both with statistical significance in blood cultures and catheter tip. Conclusions: invasive candidiasis was diagnosed in the three age groups, mainly in blood and urine, and with variability in Candida species.

RESUMEN Introducción: las micosis invasivas por Candida spp se mantienen como las más diagnosticadas en pacientes neonatales, pediátricos y adultos hospitalizados en salas de atención al grave a nivel provincial. Objetivo: identificar el principal tipo de muestra por grupo de edades y especie de Candida por tipo de muestra en neonatos y niños menores de 18 años. Métodos: estudio descriptivo, transversal sobre los aislamientos de Candida spp en hemocultivos, urocultivos, líquido cefalorraquídeo, tubo endotraqueal y punta de catéter obtenidos de pacientes neonatales, pediátricos y adultos hospitalizados en salas de atención al grave en los cinco hospitales provinciales de Villa Clara entre el primero de enero de 2018 hasta el 31 de agosto de 2019. La muestra fue de 114 aislamientos positivos. Se obtuvieron distribuciones de frecuencias absolutas, relativas, porcientos y análisis estadístico como Ji cuadrado de Pearson. Resultados: los adultos aportaron mayores números de aislamientos positivos, seguidos de los neonatos y de edad pediátrica, principalmente en el año 2018. Las muestras de sangre, seguidas de las de orina en neonatos y pacientes pediátricos fueron las más diagnosticadas; en los adultos fue a la inversa. En neonatos la Candida tropicalis y la Candida spp fueron las especies más aisladas, sin significación estadística, en pacientes pediátricos fueron la Candida spp y la Candida krusei, ambas con significación estadística en hemocultivos y punta de catéter.

BACKGROUND The evaluation of procedures for drug susceptibility prediction of Mycobacterium tuberculosis based on genomic data against the conventional reference method test based on culture is realistic considering the scenario of growing number of tools proposals based on whole-genome sequences (WGS). OBJECTIVES This study aimed to evaluate drug susceptibility testing (DST) outcome based on WGS tools and the phenotypic methods performed on isolates of M. tuberculosis Lineage 1 from the state of Pará, Brazil, generally associated with low levels of drug resistance. METHODOLOGY Culture based DST was performed using the Proportion Method in Löwenstein-Jensen medium on 71 isolates that had been submitted to WGS. We analysed the seven main genome sequence-based tools for resistance and lineage prediction applied to M. tuberculosis and for comparison evaluation we have used the Kappa concordance test. FINDINGS When comparing the WGS-based tools against the DST, we observed the highest level of agreement using TB-profiler. Among the tools, TB-profiler, KvarQ and Mykrobe were those which identified the largest number of TB-MDR cases. Comparing the four most sensitive tools regarding resistance prediction, agreement was observed for 43 genomes. MAIN CONCLUSIONS Drug resistance profiling using next-generation sequencing offers rapid assessment of resistance-associated mutations, therefore facilitating rapid access to effective treatment.

ABSTRACT Physical, chemical and biological parameters were measured in March and November 2014. These water analyses were carried out at 22 sites on the coast of Puerto San Carlos (Magdalena Bay, Baja California Sur, Mexico), with the objective of assessing water quality and identifying possible sources of water pollution and its status according to Mexican regulations. The study area was divided into three zones according to its main activity: (1) thermoelectric power station, (2) fiscal port harbor and (3) San Carlos estuary, adjacent to the to the town of the same name. The measured physical, chemical and biological parameters were temperature, salinity, dissolved oxygen, chlorophyll-a, nutrients, dissolved trace metals, and coliform bacteria. The results showed poor water quality in the three areas studied, in accordance with NOM-001-SEMARNAT-1996 and the ecological criteria for water quality CE-CCA-001/89, in particular regarding phosphate, ammonium, and silicate (unregulated) concentrations, as well as the presence of Escherichia coli. The three zones are considered sources of anthropogenic contamination whose impact is greater in the warmest month and dead tides, probably due to the entry of water contaminated by anthropogenic waste derivatives. According to the sanitary authorities of the state of Baja California Sur, the certification of water quality in Magdalena Bay has been variable: it was not certified in 2014, whilst in the period 2015-2017 it was re-certified. Although this region is an important touristic and fishing site, it is at risk of contamination due to the lack of a wastewater treatment system in the town and the inadequate disposal of raw sewage from the port.

RESUMEN En marzo y noviembre de 2014 se llevaron a cabo mediciones de parámetros físicos, químicos y biológicos del agua superficial en 22 sitios del litoral de Puerto San Carlos (Bahía Magdalena, Baja California Sur, México), con el objetivo de evaluar la calidad del agua, identificar las posibles fuentes de contaminación y su estatus de acuerdo con la reglamentación mexicana. El área de estudio fue dividida en tres zonas según su actividad principal: 1) central termoeléctrica, 2) muelle fiscal portuario y (3) estero San Carlos, aledaño al poblado del mismo nombre. Los parámetros físicos, químicos y biológicos medidos fueron: temperatura, salinidad, oxígeno disuelto, clorofila-a, nutrientes, metales traza disueltos y bacterias coliformes. Los resultados mostraron una mala calidad del agua en las tres zonas estudiadas, de acuerdo con la NOM-001-SEMARNAT-1996 y los Criterios Ecológicos de Calidad del Agua CE-CCA-001/89, en particular con relación a los niveles de fosfato, amonio, silicato (no reglamentado) y la presencia de Escherichia coli. Las tres zonas se consideran fuentes de contaminación y su impacto es mayor en el mes más cálido y en mareas muertas, debido probablemente a la entrada de aguas contaminadas con derivados de residuos antrópicos. De acuerdo con las autoridades sanitarias del estado de Baja California Sur, la certificación de calidad del agua en Bahía Magdalena ha sido variable: en 2014 no fue certificada, mientras que en el periodo 2015-2017 fue nuevamente certificada. Esta región, que constituye un importante sitio de aprovechamiento pesquero y turístico, se encuentra en riesgo de contaminación debido a la falta de un sistema de tratamiento de aguas residuales en el poblado y a la inadecuada disposición de aguas grises y negras del puerto.

Abstract INTRODUCTION: Laboratory and clinical features of childhood tuberculosis (TB) are non-specific and establishing an accurate diagnosis remains a challenge. This study evaluated a Single tube nested-PCR (STNPCR) to detect genomic DNA of Mycobacterium tuberculosis complex in blood and urine. METHODS: Biological samples were obtained from children (<15 years old) with clinical suspicion of pulmonary and extrapulmonary TB at public hospitals in Recife-Pernambuco, Brazil. Cultures yielded negative results in a majority of childhood TB cases, which are generally paucibacillary. A set of clinical, epidemiological, radiological, and laboratory criteria with evident clinical improvement after anti-TB treatment were frequently used to define childhood TB cases. RESULTS: Ninety children with clinical suspicion were enrolled in this study (44 with TB and 46 without TB). The pulmonary TB group had 20 confirmed cases and 46 negative controls, while the extrapulmonary TB group had 24 confirmed cases. The STNPCR showed sensitivities to pulmonary and extrapulmonary TB of 47.4% and 52.2% (blood) and 38.8% and 20% (urine), respectively. Considering the low performance of STNPCR on separate samples, we decided to perform a combined analysis (parallel sensitivity analysis) of the results from blood and urine samples. The parallel sensitivity increased to 65% in blood and 62.5% in urine. The specificity in both samples ranged from 93.5-97.8%. CONCLUSIONS: Although STNPCR showed moderate sensitivity, the specificity is high; therefore, the test can be used as an auxiliary tool to diagnose TB in children. It is a rapid test that demonstrated better performance than other diagnostic tests in paucibacillary samples as it does in childhood tuberculosis.

Bacillus Calmette Guerin (BCG) vaccines comprise a family of related strains. Whole genome sequencing has allowed the better characterisation of the differences between many of the BCG vaccines. As sequencing technologies improve, updating of publicly available sequence data becomes common practice. We hereby announce the draft genome of four commonly used BCG vaccines in Brazil, Argentina and Venezuela.

ABSTRACT Introduction: candidiasis is a fungal infection caused mainly by non-albicans Candida species that usually appears on the skin or mucous membranes of patients. Objective: to characterize the incidence of Candida species with the highest number of isolates in hospitalized pediatric patients, at Mariana Grajales Hospital (Neonatology Service) and José Luis Miranda Hospital, in the period 2013 - 2018, in Villa Clara. Methods: descriptive and cross-sectional study with 50 Candida genus isolates in blood cultures of patients hospitalized at Mariana Grajales Hospital (Neonatology Service) and José Luis Miranda Hospital (Intensive Care Service), Villa Clara, from January 2013 to September 2018. Descriptive and inferential statistics using Pearson's chi-squared test (χ2) or Fisher's exact test to the variables: year of study, type of hospital, type of service and isolated Candida species. Results: the largest isolates of invasive candidiasis corresponded to the Intensive Therapy service from the pediatric hospital in 2018 (only with statistical significance). In this same hospital, the Candida spp group obtained the highest index, followed by Candida tropicalis, without statistical significance. The largest number of isolates corresponded to Candida spp in the Neonatology service, followed by Candida guillermondii, both without statistical significance. Conclusions: the Intensive Therapy service was the one with the highest number of cases of invasive candidiasis and the year 2018 was the most representative. The group of Candida spp was the most isolated species in both hospitals.

RESUMEN Introducción: la candidiasis es una infección fúngica causada principalmente por especies de candida no albicans que aparece generalmente en la piel o las membranas mucosas de los pacientes. Objetivos: caracterizar la incidencia de especies de candida con mayor número de aislamientos en los pacientes pediátricos hospitalizados, en el Hospital Mariana Grajales (Servicio de Neonatología) y Hospital José Luis Miranda, en el período 2013 - 2018, en Villa Clara. Métodos: estudio descriptivo y transversal con 50 aislamientos del género candida en hemocultivos de pacientes hospitalizados Hospital Mariana Grajales (Servicio de Neonatología) y Hospital José Luis Miranda (Servicio de Terapia Intensiva), Villa Clara, de enero 2013 - septiembre 2018. Se utilizó la estadística descriptiva e inferencial, mediante el test de Ji cuadrado de Pearson (x2) o el test exacto de Fisher a las variables: año de estudio, tipo de hospital, tipo de servicio y especie de candida aislada. Resultados: los mayores aislamientos de candidiasis invasiva correspondieron al pediátrico, en el servicio de Terapia Intensiva, 2018 (única con significación estadística).En esta misma unidad, el grupo de candida spp obtuvo el mayor índice, seguido de candida tropicalis, sin significaciones estadísticas. En el servicio de Neonatología el mayor número de aislamientos correspondió a candida spp, seguido de candida guillermondii, ambas sin significación estadística. Conclusiones: el servicio de Terapia Intensiva fue el que mayor número de casos de candidiasis invasiva y el año 2018 fue el más representativo. El grupo de candida spp fueron las especies que más se aislaron en ambos hospitales.

Abstract The β-Glucans content has straight influence on the quality of malt and beer, mainly during the filtration step. Barley presenting high β-Glucan content demands longer germination time at malting. The application of commercial β-Glucanase is an alternative to accelerate the process and preserve the quality of malt. This work aimed to evaluate the effect of commercial β-Glucanase addition in malt produced within reduced germination time (64 h). Micro-malting was conducted with BRS-Caue and Elis barley cultivars at germination time 64 h and 96 h. The β-Glucanase concentration applied were 0, 25, 50 and 100 mg.kg-1. Barley, malt and wort samples were analyzed to check their physical-chemical features. Beers were produced with BRS-Caue malt and the physical-chemical and sensory attributes were analyzed. The commercial enzyme addition in BRS-Caue and Elis (64 h), at concentration 25 and 50 mg.kg-1, resulted in wort presenting proper β-Glucan content (≤ 178 mg.L-1). The beer produced with malt germinated for 64 h and added with 50 mg.kg-1 of β-glucanase was the one showing the largest number of physical-chemical and sensory parameters similar to the beer made with malt germinated for 96 h (conventional process). Commercial β-glucanase application in malt allowed accelerating the malting process without affecting the quality of the malt for beer production.

Abstract Sixteen monthly cruises were carried out at a station 6.5 km to the NW of the mouth of Magdalena Bay (Mexico) to study the temporal variability of phytoplankton biomass and primary production rates, and the response of phytoplankton to the prevailing hydrographic characteristics. During each cruise, temperature and salinity were measured in the water column, and discrete samples were collected to measure inorganic nutrient concentrations (nitrate, phosphate, and silicate) and chlorophyll a content (as a proxy for phytoplankton biomass); in addition, in situ incubations were performed to estimate primary production (PP) rates using the 14C technique. During spring and early summer (March-July), the water column at the study site was cold (14.4 ºC at 80 m depth and 17.7 ºC at the surface) and well mixed, with high nutrient concentrations (nitrate = 6.39 μM, phosphate = 0.91 μM, and silicate = 11.87 μM) at the surface, typical of intense upwelling systems. On the contrary, from August to February the water column was stratified (23.5 ± 3.2 ºC above the thermocline and 17.0 ± 1.7 ºC at 80 m depth) and had low nutrient concentrations (nitrate = 3.90 μM, phosphate = 0.47 μM, and silicate = 10.30 μM) at the surface. Phytoplankton abundance, chlorophyll a concentration, and PP rates in the euphotic zone were higher during the upwelling season, with maximum cell density of 1.7 × 106 cells·L-1 (nanoplankton fraction), integrated chlorophyll a content of 231 mg·m-2, and integrated PP rates of 553 mg Cm-2·h-1). Abundance of cells <20 μm, as determined by flow cytometry, revealed the importance of the nanoplankton and picoplankton fractions in this region. This study showed the seasonal variability of phytoplankton communities (biomass and productivity) in waters off Magdalena Bay and the coupling of phytoplankton to environmental variability. Seasonal variability was similar to that observed for other typical coastal upwelling regions, that is, higher phytoplankton abundances and PP rates in spring and summer and lower values in autumn and winter.

Resumen En el periodo de la primavera de 2013 al verano de 2014 se llevaron a cabo 16 muestreos mensuales a 6.5 km al noroeste de la boca de bahía Magdalena (México) con el propósito de estudiar la variabilidad temporal de la biomasa y las tasas de producción primaria del fitoplancton y la respuesta del mismo a las características hidrográficas predominantes. En cada muestreo se midieron la temperatura y salinidad en la columna de agua y se determinaron las concentraciones de nutrientes inorgánicos (nitrato, fosfato y silicato) y el contenido de clorofila a (como proxy de la biomasa del fitoplancton); además, se hicieron incubaciones in situ para estimar la producción primaria (PP) con el método de 14C. En primavera y principios de verano (marzo-julio), el sitio presentó, en promedio, una columna de agua fría (14.4 ºC a 80 m de profundidad y 17.7 ºC en superficie) y mezclada con concentraciones de nutrientes altas en superficie (nitrato = 6.39 µM, fosfato = 0.91 µM y silicato = 11.87µM; valores característicos de zonas de afloramiento intenso). Por el contrario, de agosto a febrero se observó una columna de agua estratificada (23.5 ± 3.2 ºC arriba de la termoclina y 17.0 ± 1.7 ºC a 80 m de profundidad) con menor contenido de nutrientes en superficie (nitrato = 3.90 µM, fosfato = 0.47 µM y silicato = 10.30 µM). La abundancia del fitoplancton, la concentración de clorofila a y las tasas de PP en la zona eufótica fueron mayores en la temporada de surgencias, con densidad celular máxima de 1.7 × 106 cél·L-1 (fracción del nanoplancton), contenido de clorofila a integrada de 231 mg·m-2 y tasa de producción integrada de 553 mg C·m-2·h-1. Las abundancias de células <20 µm determinadas por citometría de flujo mostraron la importancia de las fracciones del nano y picoplancton en la región. Este estudio mostró la variabilidad estacional de las comunidades del fitoplancton (biomasa y productividad) en las aguas frente a bahía Magdalena y su acoplamiento al cambio ambiental. La variabilidad estacional fue similar a la observada en otras regiones características de afloramientos costeros, esto es, mayores abundancias y tasas de PP en primavera y verano y valores menores en otoño e invierno.

Abstract Background: Magdalena Bay is a subtropical coastal lagoon of northwestern Mexico with important ecological con siderations and numerous fisheries. Knowledge of hydrodynamics and water quality are essential for establishing best management practices for the Bay. Goals: The aim of the study was to analyze the influence of the tide on the variation and transport of nutrients and chlorophyll a between the inner lagoon and the adjacent ocean as a fertilization mechanism in the area. Methods: Samples were obtained in June, August, and November 2005 at a site close to the mouth (24o 57´ N and 112o 03´ W). The samples were obtained every 2 hours during each tidal cycle at three different depths (0, 15, and 30 m). Temperature and salinity were measured using a CTD. Nutrients, chlorophyll a, and oxygen were measured at a laboratory. Results: Three climatic-oceanographic conditions were identified: upwelling (June), stratification (August), and negative effects during the ENSO (November). The correlation between tidal range and other variables was significant (p <0.05) in August, compared to June and November. Conclusions: The transport of net nutrients associated with the tidal cycle depends on the season and the state of the tide and is considered high compared to other smaller systems. This explains the high organic productivity in this coastal region.

Resumen Antecedentes: Bahía Magdalena es una laguna costera subtropical de alta importancia ecológica y pesquera del noroes te (NO) de México, donde se requiere consolidar el conocimiento de los procesos hidrodinámicos y la calidad de sus aguas para mejorar su aprovechamiento. Objetivos: Analizar la influencia de la marea en la variación y transporte de nutrientes y clorofila a entre la laguna y el océano adyacente como mecanismo de fertilización de la región. Métodos: Se realizaron tres muestreos en junio, agosto y noviembre de 2005 en un sitio aproximadamente a 5 km de la boca (24o 57´ N y 112o 03´ O). Se tomaron muestras cada 2 horas durante cada ciclo de marea para medir nutrientes, clorofila a y oxígeno a tres profundidades (0, 15 y 30 m), así como temperatura y salinidad mediante un CTD. Resultados: Se identificaron tres condiciones climático-oceanográficas: surgencias (junio), estratificación (agosto) y ENSO (El Niño Southern Oscilation) ne gativo (noviembre). La relación entre amplitud de marea y las variables medidas fue mayor en agosto (p < 0.05) respecto a junio y noviembre. Conclusiones: El transporte neto de nutrientes por ciclo de marea depende de la época del año y el estado de la marea y se considera alto comparado con otros sistemas de menores dimensiones y explica la elevada productividad orgánica en esta región costera.