lncRNA-Induced Spread of Polycomb Controlled by Genome Architecture, RNA Abundance, and CpG Island DNA.

Long noncoding RNAs (lncRNAs) cause Polycomb repressive complexes (PRCs) to spread over broad regions of the mammalian genome. We report that in mouse trophoblast stem cells, the Airn and Kcnq1ot1 lncRNAs induce PRC-dependent chromatin modifications over multi-megabase domains. Throughout the Airn-targeted domain, the extent of PRC-dependent modification correlated with intra-nuclear distance to the Airn locus, preexisting genome architecture, and the abundance of Airn itself. Specific CpG islands (CGIs) displayed characteristics indicating that they nucleate the spread of PRCs upon exposure to Airn. Chromatin environments surrounding Xist, Airn, and Kcnq1ot1 suggest common mechanisms of PRC engagement and spreading. Our data indicate that lncRNA potency can be tightly linked to lncRNA abundance and that within lncRNA-targeted domains, PRCs are recruited to CGIs via lncRNA-independent mechanisms. We propose that CGIs that autonomously recruit PRCs interact with lncRNAs and their associated proteins through three-dimensional space to nucleate the spread of PRCs in lncRNA-targeted domains.

Anthropometric and bioimpedance equations for fat and fat-free mass in Chilean children 7-9 years of age.

Assessing children's growth adequately is important due to the necessary prevention of adequate body composition, especially at pre-pubertal age. Simpler measurements such as anthropometry or bioimpedance, using equations validated in Caucasian children, have been demonstrated to overestimate or underestimate fat mass percentage (FM%) or fat-free mass (FFM) in Chilean children. In a sample of 424 children (198 boys and 226 girls) of 7-9 years old, the three component (3C) model was assessed, where total body water was determined by 2H dilution and body volume by air displacement plethysmography, in order to design and validate anthropometry and bioimpedance equations. The FM (%) equation specific for Chilean children was validated as (1·743 × BMI z-score) + (0·727 × triceps skinfold) + (0·385 × biceps skinfold) + 15·985, against the 3C model (R2 0·79). The new FFM equation (kg) generated was (log FFM = (0·018 × age) + (0·047 × sex) + (0·006 × weight) + (0·027 × resistance) + 2·071), with an R2 0·93 (female = 1 and male = 2). The Bland-Altman analysis shows a mean difference of 0·27 (sd 3·5) for the FM% in the whole group as well as 0·004 (sd 0·9) kg is the mean difference for the bioelectrical impedance analysis (BIA) FFM (kg) equation. The new equations for FM (%) and FFM (kg) in Chilean children will provide a simple and valid tool for the assessment of body composition in cohort studies or to assess the impact of nutritional programmes or public policies.

Glia multitask to compensate for neighboring glial cell dysfunction.

As glia mature, they undergo glial tiling to abut one another without invading each other's boundaries. Upon the loss of the secreted neurotrophin Spätzle3 (Spz3), Drosophila cortex glia transform morphologically and lose their intricate interactions with neurons and surrounding glial subtypes. Here, we reveal that all neighboring glial cell types (astrocytes, ensheathing glia, and subperineurial glia) react by extending processes into the previous cortex glial territory to compensate for lost cortex glial function and reduce the buildup of neuronal debris. However, the loss of Spz3 alone is not sufficient for glia to cross their natural borders, as blocking CNS growth via nutrient-restriction blocks the aberrant infiltration induced by the loss of Spz3. Surprisingly, even when these neighboring glia divert their cellular resources beyond their typical borders to take on new compensatory roles, they are able to multitask to continue to preserve their own normal functions to maintain CNS homeostasis.

Actionable mutations in non-small cell lung cancer in patients at hospital de Especialidades Eugenio Espejo, Ecuador 2017-2020.

OBJECTIVES: Determine the frequency of actionable mutations in non-small cell lung cancer (NSCLC) and their correlation with overall survival (OS) and the site of metastases. METHODS: We performed a descriptive cross-sectional study at the Hospital de Especialidades Eugenio Espejo, Ecuador, between 2017 and 2020. Demographic, pathological, and molecular alterations in epidermal growth factor (EGFR), Anaplastic lymphoma kinase (ALK), ROS proto-oncogene 1 (ROS1), Programmed death-ligand 1 (PD-L1) expression, and clinical data detailed in patients' medical records with metastatic NSCLC were collected and analyzed. Seventy-nine stage IV patients had NSCLC; adenocarcinoma histology represents 56 (70.9%). The predominant mutation was in EGFR (22.8%); the most common variant was the deletion of exon 19 (72.2%). The most common metastatic site was in the contralateral lung (22.3%); however, this variable showed no significant correlation to the molecular markers (p=0.057). The overall survival (OS) and the status of molecular markers are not statistically significant (p=0.27). OS was better for non-mutated EGFR than for mutated EGFR (p=0.012). However, the frequency values are unrelated to contralateral lung metastasis or survival. CONCLUSIONS: Our frequency mutations are concordant with those found in other studies in Latin America. EGFR was the most common biomarker mutation, and there was a better OS in EGFR non-mutated patient.

Early Draper-mediated glial refinement of neuropil architecture and synapse number in the Drosophila antennal lobe.

Glial phagocytic activity refines connectivity, though molecular mechanisms regulating this exquisitely sensitive process are incompletely defined. We developed the Drosophila antennal lobe as a model for identifying molecular mechanisms underlying glial refinement of neural circuits in the absence of injury. Antennal lobe organization is stereotyped and characterized by individual glomeruli comprised of unique olfactory receptor neuronal (ORN) populations. The antennal lobe interacts extensively with two glial subtypes: ensheathing glia wrap individual glomeruli, while astrocytes ramify considerably within them. Phagocytic roles for glia in the uninjured antennal lobe are largely unknown. Thus, we tested whether Draper regulates ORN terminal arbor size, shape, or presynaptic content in two representative glomeruli: VC1 and VM7. We find that glial Draper limits the size of individual glomeruli and restrains their presynaptic content. Moreover, glial refinement is apparent in young adults, a period of rapid terminal arbor and synapse growth, indicating that synapse addition and elimination occur simultaneously. Draper has been shown to be expressed in ensheathing glia; unexpectedly, we find it expressed at high levels in late pupal antennal lobe astrocytes. Surprisingly, Draper plays differential roles in ensheathing glia and astrocytes in VC1 and VM7. In VC1, ensheathing glial Draper plays a more significant role in shaping glomerular size and presynaptic content; while in VM7, astrocytic Draper plays the larger role. Together, these data indicate that astrocytes and ensheathing glia employ Draper to refine circuitry in the antennal lobe before the terminal arbors reach their mature form and argue for local heterogeneity of neuron-glia interactions.

The IPDGC/GP2 Hackathon - an open science event for training in data science, genomics, and collaboration using Parkinson's disease data.

Open science and collaboration are necessary to facilitate the advancement of Parkinson's disease (PD) research. Hackathons are collaborative events that bring together people with different skill sets and backgrounds to generate resources and creative solutions to problems. These events can be used as training and networking opportunities, thus we coordinated a virtual 3-day hackathon event, during which 49 early-career scientists from 12 countries built tools and pipelines with a focus on PD. Resources were created with the goal of helping scientists accelerate their own research by having access to the necessary code and tools. Each team was allocated one of nine different projects, each with a different goal. These included developing post-genome-wide association studies (GWAS) analysis pipelines, downstream analysis of genetic variation pipelines, and various visualization tools. Hackathons are a valuable approach to inspire creative thinking, supplement training in data science, and foster collaborative scientific relationships, which are foundational practices for early-career researchers. The resources generated can be used to accelerate research on the genetics of PD.

Observational analysis of clinical and pathological characteristics and their prognostic impact in Mexican patients with breast cancer: A multi-center study.

Breast cancer is the most incidental and deadly neoplasm worldwide; in Mexico, very few epidemiologic reports have analyzed the pathological features and its impact on their clinical outcome. Here, we studied the relation between pathological features and the clinical presentation at diagnosis and their impact on the overall and progression-free survival of patients with breast cancer. For this purpose, we collected 199 clinical records of female patients, aged at least 18 years old (y/o), with breast cancer diagnosis confirmed by biopsy. We excluded patients with incomplete or conflicting clinical records. Afterward, we performed an analysis of overall and progression-free survival and associated risks. Our results showed an average age at diagnosis of 52 y/o (24-85), the most common features were: upper outer quadrant tumor (32%), invasive ductal carcinoma (76.8%), moderately differentiated (44.3%), early clinical stages (40.8%), asymptomatic patients (47.8%), luminal A subtype (47.8%). Median overall survival was not reached, but median progression-free survival was 32.2 months (29.75-34.64, CI 95%) associated risk were: clinical stage (p < 0.0001) symptomatic presentation (p = 0.009) and histologic grade (p = 0.02). Therefore, we concluded that symptom presence at diagnosis impacts progression-free survival, and palpable symptoms are related to an increased risk for mortality.

Elevated Risk of Overweight/Obesity-Related Markers and Low Muscular Fitness in Children Attending Public Schools in Chile.

In Chile, children of low socioeconomic status usually attend public schools and have few opportunities to engage in healthy behaviors. This may increase their risk of overweight/obesity and low muscular fitness. Therefore, we aimed to determine the association between the school type attended with overweight/obesity-related markers and the muscular fitness of children in Chile. We included 1410 children (6-13 years old) attending public, subsidized, or private schools. Overweight/obesity-related markers included BMI Z-scores, waist circumference, and body fat percentage. Muscular fitness assessment included handgrip strength and standing long jump. The odds ratios [95% CI] of overweight/obesity, elevated waist circumference, elevated body fat, low handgrip strength, and low standing long jump were compared between school types. Compared with boys attending public schools, those attending subsidized or private schools had lower odds ratios of low handgrip strength (0.63 [0.42-0.94] and 0.44 [0.25-0.78], respectively). Girls attending subsidized schools, compared with those in public schools, had lower odds of overweight/obesity (0.63 [0.44-0.90]) and of having low handgrip strength (0.51 [0.34-0.78]). Compared with girls in public schools, those attending private schools had lower odds (vs. public schools) of overweight/obesity (0.45 [0.28-0.74]), of having elevated body fat (0.53 [0.29-0.96]), and of having low standing long jump (0.41 [0.21-0.77]). The elevated risk of overweight/obesity-related markers and lower muscular fitness in children, particularly girls, attending public schools increase their current and future disease risk. This suggests that childhood socioeconomic status plays a central role in determining disease risk. Health-promoting interventions specifically focused on children from disadvantaged contexts are required.

The influence of body composition on the six-minute walk test in Chilean preschool and school children.

INTRODUCTION: Background: the six minutes' walk test (6MWT) measures submaximal physical activity. Objective: this study determines the association of children´s nutritional status and body composition with the results of the 6MWT. Methods: a sample of 1419 Chilean children, 4 to 10 years of age, were assessed including anthropometry, body composition by validated equations, the 6MWT test, and in 50 % of the sample heart rate prior the test, at one minute into the test, and at one minute posttest with a Polar watch. Results: the distance walked ranged from 473.1 ± 47.8 meters in preschool children to 584.2 ± 65.7 meters in school children. In heart rate there was a significant difference between obese and eutrophic children. The distance walked in the 6MWT was positively associated with fat-free mass (p < 0.05) and BMI (R2 = 0.49). Body composition influences 6MWT quartile distribution, as well as nutritional status. Age and height explained 49 % of the variance (R2 = 0.42 and 0.47, respectively) in the 6MWT, and there are significant differences in this variable by sex, body composition, and nutritional status. Conclusions: body composition was associated with walking performance in children. Thus, it is important to evaluate height and body composition when assessing the six-minute walk test because of this important relationship.

INTRODUCCIÓN: Introducción: el test de la marcha de seis minutos (TM6M) mide una actividad física submáxima. Este estudio evaluó el efecto del test de la marcha sobre la composición corporal y el estado nutricional en niños. Métodos: en una muestra de 1419 niños chilenos de 4 a 10 años de edad se evaluaron la antropometría, la composición corporal por ecuaciones validadas, el TM6M y, en el 50 % de la muesta, la frecuencia cardíaca mediante un reloj Polar. Resultados: la distancia caminada varió desde 473,1 ± 47,8 metros en los niños preescolares hasta 584,2 ± 65,7 metros en los escolares. En la frecuencia cardíaca hubo una diferencia significativa entre niños obesos y eutróficos. La distancia caminada se asoció positivamente con la masa libre de grasa (R2 = 0,37) y el IMC (R2 = 0,49). Por otra parte, la composición corporal varía en función de los cuartiles de composición corporal y el estado nutricional. La edad y la altura explicaron el 49 % de la varianza de la prueba (R2 = 0,42 and 0,47, respectivamente). Existen diferencias significativas en la distancia recorrida en el TM6M en función del sexo, la composición corporal y el estado nutricional. Conclusiones: composición corporal, talla e IMC se asociaron a la distancia recorrida en el TM6M. Por tanto, se sugiere medir estas variables cuando se evalúe el test de marcha de seis minutos.

Quantifying Glial-Glial Tiling Using Automated Image Analysis in Drosophila.

Not only do glia form close associations with neurons throughout the central nervous system (CNS), but glial cells also interact closely with other glial cells. As these cells mature, they undergo a phenomenon known as glial tiling, where they grow to abut one another, often without invading each other's boundaries. Glial tiling occurs throughout the animal kingdom, from fruit flies to humans; however, not much is known about the glial-glial interactions that lead to and maintain this tiling. Drosophila provide a strong model to investigate glial-glial tiling, where tiling occurs both among individual glial cells of the same subtype, as well as between those of different subtypes. Furthermore, the spatial segregation of the CNS allows for the unique ability to visualize and manipulate inter-subtype interactions. Previous work in Drosophila has suggested an interaction between cortex glia and astrocytes, where astrocytes cross the normal neuropil-cortex boundary in response to dysfunctional cortex glia. Here, we further explore this interaction by implementing an automated pipeline to more fully characterize this astrocyte-cortex glial relationship. By quantifying and correlating the extent of cortex glial dysfunction and aberrant astrocyte infiltration using automated analysis, we maximize the size of the quantified dataset to reveal subtle patterns in astrocyte-cortex glial interactions. We provide a guide for creating and validating a fully-automated image analysis pipeline for exploring these interactions, and implement this pipeline to describe a significant correlation between cortex glial dysfunction and aberrant astrocyte infiltration, as well as demonstrate variations in their relationship across different regions of the CNS.

Cross-sectional association between physical fitness and cardiometabolic risk in Chilean schoolchildren: the fat but fit paradox.

Background: Previous studies have examined the "fat but fit" paradox, revealing that greater levels of physical fitness may diminish the harmful consequences of excess weight on cardiometabolic risk. Despite the above, specific information about the "fat but fit" paradox in prepuberal population is scarce. The aim of this study was to determine the relationship between cardiometabolic risk across (individual and combined) physical fitness and excess weight status and whether the "fat but fit" paradox is met in the sample of schoolchildren analyzed. Methods: A cross-sectional study was conducted including 452 children (59.1% girls), aged 7-9 years from Santiago (Chile). Physical fitness was assessed as cardiorespiratory fitness and muscular fitness. Cardiorespiratory fitness was determined by the 6-minute-walk-test and muscle strength was assessed by the handgrip and standing long jump tests. Excess weight (overweight and obesity) was computed through body mass index (z-score). Cardiometabolic risk was established by summing the z-score of the serum glucose, triglycerides, high-density lipoprotein, insulin and waist-to-height ratio. Results: Schoolchildren with high physical fitness (individual or combined) showed the lowest cardiometabolic risk mean scores (P for trend <0.001 for all physical fitness groups). Conversely, schoolchildren with low physical fitness (individual or combined) showed the highest cardiometabolic risk mean scores (P for trend <0.001 for all categories). Additionally, schoolchildren without excess weight and with high individual or combined physical fitness status exhibits lower cardiometabolic risk mean scores compared to schoolchildren with excess weight and low physical fitness status (individual or combined) (P for trend <0.001 for all physical fitness groups). A lower odd of having high cardiometabolic risk was found in schoolchildren without excess weight and with both high physical fitness (both cardiorespiratory fitness and muscular fitness) [odds ratio (OR) =0.08; 95% confidence interval (CI): 0.04 to 0.16] in comparison to those with excess weight and low physical fitness. Conclusions: Our results suggest that improvements in both fatness and aerobic fitness could be associated with lower cardiometabolic risk.

Evaluation of the anxiolytic-like effects of clomipramine in two rat strains with different anxiety vulnerability (Wistar and Wistar-Kyoto rats): participation of 5-HT1A receptors.

The main aim of this study was to evaluate the anxiolytic-like effects of the serotonergic antidepressant, clomipramine (0.6-5.0 mg/kg), and the 5-HT1A agonist, (±)8-hydroxy-2-(di-n)-propil-aminotetraline hydrobromide (8-OH-DPAT; 0.01-0.5 mg/kg), in two strains of rat with different anxiety vulnerability: Wistar-Kyoto (WKY; with trait anxiety) and Wistar rats (control strain). The anxiety model used was the burying behavior test; decreases in burying, grooming of the snout, and freezing were interpreted as a reduction of anxiety-like levels. A second objective was to explore the participation of 5-HT1A receptors in the effects of clomipramine and 8-OH-DPAT. Behavior in the burying behavior test was strain dependent. In addition to the burying behavior, WKY rats showed high levels of freezing and grooming of the snout. Clomipramine and 8-OH-DPAT decreased the burying behavior in both strains of rats through a direct interaction with the 5-HT1A receptor. 8-OH-DPAT decreased freezing behavior in both strains through a mechanism that was not related to 5-HT1A receptors. Finally, clomipramine was able to block freezing and grooming behaviors only in WKY rats. In conclusion, strains with different anxiety vulnerability express different behavioral responses toward the same aversive stimulus, and the anxiolytic-like effects of clomipramine and 8-OH-DPAT are both behavior and strain dependent.

A new doubly labelled water anthropometry-based equation for prediction of total daily energy expenditure in older people from low- and middle-income countries.

BACKGROUND: For community-living older people, the ability to estimate total daily energy expenditure (TDEE) with validated predictive equations based on anthropometry is limited. To our knowledge no studies exist for non-Caucasian populations OBJECTIVE: To design and validate an anthropometry-based equation to estimate TDEE using doubly-labelled water (DLW) as the criterion measure, and to assess the performance of three other published equations in community-living older people from rural and urban areas of Brazil, Chile, Guatemala, Senegal, Cuba, and Mexico METHODS: This cross-sectional study measured anthropometry and TDEE using DLW in 69 men and 43 women aged 60-89 years. TDEE was also estimated with an anthropometry-based equation derived from the sub-sample of Mexico (n = 38) and with three other published equations. Predictive accuracy of the equations was tested by an external validation procedure RESULTS: TDEE by DLW in the six country sample was 2411 ± 41 kcal/day (mean ± SE) in men and 1939 ± 51 kcal/day in women. The best new Mexican equation was TDEE, kcal/d = [223.4 + (27.9 × weight, kg) + (239.7 × sex)]; where sex: Man = 1 and Woman = 0; having high precision; R2 = 0.89, lowest RMSE = 149.2, and Cp value of 2.0. This new Mexican equation estimated TDEE accurately in the five country sample and at country level after correction for Guatemalan older men, while the published equations performed poorly CONCLUSIONS: The Mexican equation performed better that other published equations and is recommended to accurately estimate energy requirements for community-living older people in five Latin American and one African country.

SAPS 3 in the modified NUTrition RIsk in the Critically ill score has comparable predictive accuracy to APACHE II as a severity marker. / Uso do SAPS 3 no escore NUTrition RIsk in the Critically ill modificado tem precisão preditiva comparável ao uso do APACHE II como marcador de gravidade.

OBJECTIVE: To evaluate the substitution of Acute Physiology and Chronic Health Evaluation II (APACHE II) by Simplified Acute Physiology Score 3 (SAPS 3) as a severity marker in the modified version of the NUTrition RIsk in the Critically ill score (mNUTRIC); without interleukin 6) based on an analysis of its discriminative ability for in-hospital mortality prediction. METHODS: This retrospective cohort study evaluated 1,516 adult patients admitted to an intensive care unit of a private general hospital from April 2017 to January 2018. Performance evaluation included Fleiss' Kappa and Pearson correlation analysis. The discriminative ability for estimating in-hospital mortality was assessed with the Receiver Operating Characteristic curve. RESULTS: The sample was randomly divided into two-thirds for model development (n = 1,025; age 72 [57 - 83]; 52.4% male) and one-third for performance evaluation (n = 490; age 72 [57 - 83]; 50.8% male). The agreement with mNUTRIC was Kappa of 0.563 (p < 0.001), and the correlation between the instruments was Pearson correlation of 0.804 (p < 0.001). The tool showed good performance in predicting in-hospital mortality (area under the curve 0.825 [0.787 - 0.863] p < 0.001). CONCLUSION: The substitution of APACHE II by SAPS 3 as a severity marker in the mNUTRIC score showed good performance in predicting in-hospital mortality. These data provide the first evidence regarding the validity of the substitution of APACHE II by SAPS 3 in the mNUTRIC as a marker of severity. Multicentric studies and additional analyses of nutritional adequacy parameters are required.

OBJETIVO: Avaliar o Simplified Acute Physiology Score 3 (SAPS 3) como substituto do Acute Physiology and Chronic Health Evaluation II (APACHE II) como marcador de gravidade na versão modificada do escore NUTrition RIsk in the Critically ill (mNUTRIC; sem interleucina 6), com base em uma análise de sua capacidade discriminativa para predição de mortalidade hospitalar. MÉTODOS: Este estudo de coorte retrospectiva avaliou 1.516 pacientes adultos internados em uma unidade de terapia intensiva de um hospital geral privado entre abril de 2017 e janeiro de 2018. A avaliação de desempenho incluiu as análises Kappa de Fleiss e correlação de Pearson. A capacidade discriminativa para estimar a mortalidade hospitalar foi avaliada com a curva Característica de Operação do Receptor. RESULTADOS: A amostra foi dividida aleatoriamente em dois terços para o desenvolvimento do modelo (n = 1.025; idade 72 [57 - 83]; 52,4% masculino) e um terço para avaliação do desempenho (n = 490; idade 72 [57 - 83]; 50,8 % masculino). A concordância com o mNUTRIC foi Kappa de 0,563 (p < 0,001), e a correlação entre os instrumentos foi correlação de Pearson de 0,804 (p < 0,001). A ferramenta mostrou bom desempenho para prever a mortalidade hospitalar (área sob a curva de 0,825 [0,787 - 0,863] p < 0,001). CONCLUSÃO: A substituição do APACHE II pelo SAPS 3 como marcador de gravidade no escore mNUTRIC mostrou bom desempenho para predizer a mortalidade hospitalar. Esses dados fornecem a primeira evidência sobre a validade da substituição do APACHE II pelo SAPS 3 no mNUTRIC como marcador de gravidade. São necessários estudos multicêntricos e análises adicionais dos parâmetros de adequação nutricional.

[Body composition assessment before and after weight loss following a Roux-en-Y gastric bypass. Are bioimpedanciometry estimations reliable?] / Evaluación de la composicion corporal antes y después de la reducción de peso con baipás gastrico en Y de Roux. ¿Son confiables las mediciones de la bioimpedanciometría?

INTRODUCTION: Introduction: in patients with severe and morbid obesity it has been observed that bioimpedance (BIA) assessment generates an underestimation of fat mass (FM) and weight loss as FM after bariatric surgery, overestimating the loss of fat-free mass (FFM) and muscle mass. Objective: to evaluate the reliability of bioelectrical impedance analysis (BIA) to estimate total body water (TBW), fat-free mass (FFM), fat mass (FM), and its changes after 6 months of a Roux-en-Y gastric bypass (RYGBP), in patients with severe and morbid obesity. Methods: thirty-six patients approved for RYGBP were prospectively studied. TBW was measured by deuterium (D), and FM and FFM were calculated. A dual-frequency BIA device (5 and 200 kHz) (Bodystat Dualscan®) was used to estimate FM, FFM, TBW, extracellular water (ECW), intracellular water (ICW), and ECW/ICW ratio. Results: before RYGBP, BIA overestimated TBW by 2.6 ± 4.3 L (p = 0.002) and FFM by 3.5 ± 5.7 kg (p = 0.002), and underestimated FM% by 2.98 ± 4.7% (p = 0.002). The ECW/ICW ratio showed a significant and positive correlation with the difference BIA-D for FFM (r = 0.49; p = 0.002). After surgery, the differences between BIA and D were not significant, and the estimation error of FFM did not correlate with the ECW/ICW ratio. Conclusions: BIA generates an underestimation of FM as reported in patients with severe and morbid obesity, which is attenuated after weight reduction, underestimating weight loss as FM and overestimating FFM loss. Future research may assess whether these errors are reproduced by other BIA devices.

INTRODUCCIÓN: Introducción: en pacientes con obesidad severa y mórbida se ha observado que la evaluación por bioimpedanciometría (BIA) genera una subestimación de la masa grasa (MG) y del peso perdido como MG después de la cirugía bariátrica, sobreestimándose la pérdida de masa libre de grasa (MLG) y la masa muscular. Objetivo: evaluar la confiabilidad de la BIA para estimar el agua corporal total (ACT), la MLG, la MG y sus cambios después de 6 meses de un baipás gástrico en Y de Roux (BPGYR) en pacientes con obesidad severa y mórbida. Métodos: 36 adultos con indicación de BPGYR se estudiaron prospectivamente. Se midió el ACT por deuterio (D) y se calcularon la MLG y MG. Con BIA de doble frecuencia (5 y 200 kHz) (Bodystat Dualscan®) se estimaron la MG, la MLG, el ACT, el agua extracelular (AEC), el agua intracelular (AIC) y la relación AEC/AIC. Resultados: antes del BPGYR, la BIA sobreestimó el ACT en 2,6 ± 4,3 L (p = 0,002) y la MLG en 3,5 ± 5,7 kg (p = 0,002), y subestimó el %MG en 2,98 ± 4,7% (p = 0,002). La relación AEC/AIC mostró una correlación positiva con la sobreestimación de la MLG por BIA (r = 0,49; p = 0,002). Después de la cirugía, las diferencias entre BIA y D no fueron significativas y el error de estimación de la MLG no se correlacionó con la relación AEC/AIC. Conclusiones: la BIA genera una subestimación de la MG como la reportada, la cual se atenúa después de la reducción de peso, subestimando el peso perdido como MG y sobreestimando la pérdida de MLG. Futuras investigaciones podrán evaluar si estos errores se reproducen con otros equipos de BIA.

[Obesity prevention in preschool and schoolchildren attending public schools from a district of Santiago, Chile: pilot project 2006]. / Prevención de obesidad en preescolares y escolares de escuelas municipales de una Comuna de Santiago de Chile: proyecto piloto 2006.

Childhood obesity in Chile has been recognized as a public health problem. In 2006, we developed a school-based obesity prevention pilot project to intervene during 5 months preschool and schoolchildren from 1st to 4th grades attending 7 public schools located in a district of Santiago, Chile of medium-low and low SES. The objective of this project was to evaluate the feasibility of implementing a longer intervention giving recommendations to the educational authorities to better implement it. We trained teachers to apply educational activities ( in nutrition and physical activity) for the children in the 7 schools, but additionally in 4 of these schools, teachers of those grades participated in a Counselling program on healthy lifestyle applied individually, anthropometric evaluation and blood tests. The initiatives were evaluated on a sample of 522 schoolchildren (nutritional status and physical fitness), 38 teachers with Counselling (BMI, waist circumference or WC, blood sugar, HDL, triglycerides, cholesterol) and 19 teachers with no counselling (BMI and WC). Additionally, we evaluated the quality of PE classes. The results on the children show a trend on only the younger ones to decrease the % obesity, improving significantly their physical fitness. In teachers with counselling, a trend toward decreasing BMI and WC was observed, while biochemical parameters remained unchanged. We showed that it is feasible to implement a longer intervention recommending improving the quality of PE classes and allowing more time to train teachers and for individual counselling.

High-throughput screening and classification of chemicals and their effects on neuronal gene expression using RASL-seq.

We previously used RNA-seq to identify chemicals whose effects on neuronal gene expression mimicked transcriptional signatures of autism, aging, and neurodegeneration. However, this approach was costly and time consuming, which limited our study to testing a single chemical concentration on mixed sex cortical neuron cultures. Here, we adapted a targeted transcriptomic method (RASL-seq, similar to TempO-seq) to interrogate changes in expression of a set of 56 signature genes in response to a library of 350 chemicals and chemical mixtures at four concentrations in male and female mouse neuronal cultures. This enabled us to replicate and expand our previous classifications, and show that transcriptional responses were largely equivalent between sexes. Overall, we found that RASL-seq can be used to accelerate the pace at which chemicals and mixtures that transcriptionally mimic autism and other neuropsychiatric diseases can be identified, and provides a cost-effective way to quantify gene expression with a panel of marker genes.

Choice of vehicle affects pyraclostrobin toxicity in mice.

Pyraclostrobin is a strobilurin fungicide that inhibits mitochondrial complex III of fungal and mammalian cells. In toxicity studies that were used to estimate the safety factor, pyraclostrobin was added to animal feed or to aqueous vehicles. However, foods containing residues of pyraclostrobin and other strobilurin fungicides (azoxystrobin, trifloxystrobin, fluoxastrobin) are frequently prepared in vegetable oil prior to human consumption. The primary objective of this study was to determine if pyraclostrobin dissolved in an oil-based vehicle had adverse health outcomes in mice when compared to aqueous-based vehicles. We found that pyraclostrobin does not fully dissolve in aqueous methyl cellulose (MC) or carboxymethyl cellulose (CMC), two vehicles used in industry-sponsored toxicity studies, but does fully dissolve in corn oil. Moreover, C57BL/6 mice receiving pyraclostrobin in corn oil displayed adverse health outcomes, including loss of body weight, hypothermia and diarrhea at lower doses than when added to feed or to aqueous vehicles. Our data suggest that previous studies underestimated the true toxicity of pyraclostrobin in mammals. Additional toxicity tests using oil-based vehicles are recommended to verify current safety recommendations for strobilurin fungicides.

Presence and diversity of Salmonella isolated from layer farms in central Ecuador.

Background: Given the considerable role played by Salmonella in the incidence of food poisoning around the world, surveillance of this infection is prioritized by both food producers and health care authorities. Data remains insufficient concerning the prevalence of Salmonella in poultry systems in Ecuador and in Latin America in general. Methods: In this study we evaluated the prevalence and diversity of Salmonella serovars in samples taken from 21 layer farms and backyard layers in central Ecuador during August-November 2017.   Salmonella was isolated following standardized methods (ISO 6579) and the serovar determination was carried out by PCR. Results: A significant presence of Salmonella was detected, with an incidence of 76% (95% confidence interval (CI): 58-94) in farms, 33% (95%CI: 13-53) in pooled cloacal swabs from layer hens, 33% (95%CI: 12-55) on feed samples, and 10% (95%CI: 0-22) in backyard layer feces from traditional local markets. The dominant serovars detected were S. Infantis and S. Typhimurium. Conclusions: This study forms a basis for further surveillance of Salmonella serovars in layer farms in central Ecuador.

Nutritional profile and mortality in patients undergoing percutaneous endoscopic gastrostomy.

INTRODUCTION: Background: malnutrition is a common problem in hospitalized patients, being associated with increased morbidity, mortality and costs. Multiple factors contribute to a deficient nutritional status, making malnutrition the cause or consequence of severe diseases. Percutaneous endoscopic gastrostomy (PEG) is a minimally invasive procedure indicated for long-term administration of enteral nutrition in patients with limited ability for oral intake who have an intact, functional gastrointestinal tract. The aim of this study was to determine the profile of patients undergoing PEG in a tertiary hospital in southern Brazil. Methods: single-center retrospective study of all patients who underwent PEG from January 1st to December 31st, 2016, in a private tertiary hospital located in southern Brazil. Data were collected retrospectively from the patients' medical records, including nutritional status, indications, complications and outcomes. Results: one hundred and thirty-three patients underwent PEG at our institution and were eligible for inclusion in the study. Median patient age was 82 years, and 57.9% were females. The main indication for PEG was dementia syndrome, followed by stroke. As much as 68.4% were diagnosed as severely malnourished and 23.0% had procedure-related complications. Conclusions: PEG tubes are being increasingly used for enteral nutrition in patients with dysphagia or inability to maintain adequate nutritional intake. The findings of the present study highlight the importance of regular nutritional risk screening by a multidisciplinary team, paying special attention to the patient's nutritional status and conditions that may place the patient at risk of developing dysphagia, with the implementation of measures to minimize malnutrition in hospitalized patients.

INTRODUCCIÓN: Introducción: la desnutrición es común en pacientes hospitalizados y se está convirtiendo en causa o consecuencia de enfermedades graves, asociándose a morbilidad, mortalidad y costos aumentados. Múltiples factores contribuyen a un estado nutricional deficiente. La gastrostomía endoscópica percutánea (PEG) es un procedimiento mínimamente invasivo para la administración de nutrición enteral en pacientes con capacidad limitada de ingesta oral que tengan el tracto gastrointestinal intacto y funcional. El objetivo de este estudio fue determinar el perfil de pacientes sometidos a PEG en un hospital terciario del sur de Brasil. Métodos: estudio retrospectivo unicéntrico de todos los pacientes sometidos a PEG del 1 de enero al 31 de diciembre de 2016 en un hospital terciario privado del sur de Brasil. Se recolectaron los datos retrospectivamente en los registros médicos, incluyendo estado nutricional, indicaciones, complicaciones y evolución. Resultados: ciento treinta y tres pacientes se sometieron a PEG en nuestra institución y fueron elegibles para el estudio. La edad mediana fue de 82 años y el 57,9% eran mujeres. Las principales indicaciones para PEG fueron demencia y accidente cerebrovascular. El 68,4% fueron diagnosticados con desnutrición grave y el 23,0% presentaron complicaciones relacionadas al procedimiento. Conclusiones: se utilizan cada vez más tubos de PEG para nutrición enteral en pacientes disfágicos o incapaces de mantener una ingesta nutricional adecuada. Nuestros hallazgos señalan la importancia del cribado para riesgo nutricional por un equipo multidisciplinario, con atención especial al estado nutricional del paciente y a condiciones que pueden ponerlo en riesgo para disfagia y la implementación de medidas para minimizar la desnutrición.