[Reduction in Helicobacter pylori infection among patients referred for upper gastrointestinal endoscopy in Santiago, Chile, between 2010-2020]. / Reducción de la infección por Helicobacter pylori en pacientes derivados a endoscopia digestiva alta en Santiago de Chile entre 2010-2020.

Latin America presents a high prevalence of Helicobacter pylori(Hp) infection. Between1996-2003, the prevalence in Santiago, Chile, was 70%; recent studies indicate a decreasein this infection. Updating the frequency of Hp is crucial due to its associated health impact. OBJECTIVE: Our objective was to describe the trend in Hp infection in patients undergoingambulatory esophagogastroduodenoscopy (EGD) in a Chilean population. MATERIALS AND METHODS: A retrospective observational study was conducted on patients over 18 years old who attended a first EGD with a rapid urease test between 2010-2020. Time trendswere described through time series analysis. A Poisson model was constructed to estimatethe risk of infection, adjusted for age and gender. RESULTS: 11,355 patients were included[66.9% females; mean age 52 years; Hp 41.6%]. Male gender presented a higher frequencyof Hp infection [RR 1.13; (95% CI: 1.08-1.18)].Hp frequency infection decreased significantlyfrom 45.1% in 2010 to 29% in 2020, with a 36% lower probability of Hp infection in 2020 compared to 2010 [RR 0.64;(95% CI: 0.55-0.74)]. A progressive decline in Hp infectiontrend was projected, reaching values close to 25% by year 2025. CONCLUSION: A significantreduction in Hpinfection was observed between 2010-2020. This decrease could be explained by the implementation of public health policies in the last decade associated with socio-sanitary changes.

Arsenic and fluoride in groundwater triggering a high risk: Probabilistic results using Monte Carlo simulation and species sensitivity distribution.

The widespread presence of arsenic (As) and fluoride (F-) in groundwater poses substantial risks to human health on a global scale. These elements have been identified as the most prevalent geogenic contaminants in groundwater in northern Mexico. Consequently, this study aimed to evaluate the human health and ecological risks associated with the content of As and F- in the Meoqui-Delicias aquifer, which is in one of Mexico's most emblematic irrigation districts. Concentrations of As and F- were measured in 38 groundwater samples using ICP-MS and ion chromatography, respectively. Overall, these elements showed a similar trend across the aquifer, revealing a positive correlation between them and pH. The concentration of As and F- in the groundwater ranged from 5.3 µg/L to 303 µg/L and from 0.5 mg/L to 8.8 mg/L, respectively. Additionally, the levels of As and F- surpassed the established national standards for safe drinking water in 92% and 97% of samples, respectively. Given that groundwater is used for both agricultural purposes and human activities, this study also assessed the associated human health and ecological risks posed by these elements using Monte Carlo simulation and Species Sensitivity Distribution. The findings disclosed a significant noncarcinogenic health risk associated with exposure to As and F-, as well as an unacceptable carcinogenic health risk to As through water consumption for both adults and children. Furthermore, a high ecological risk to aquatic species was identified for F- and high to medium risks for As in the sampling sites. Therefore, the findings in this study provide valuable information for Mexican authorities and international organizations (e.g., WHO) about the adverse effects that any exposure without treatment to groundwater from this region represents for human health.

Identifying Progression-Specific Alzheimer's Subtypes Using Multimodal Transformer.

Alzheimer's disease (AD) is the most prevalent neurodegenerative disease, yet its current treatments are limited to stopping disease progression. Moreover, the effectiveness of these treatments remains uncertain due to the heterogeneity of the disease. Therefore, it is essential to identify disease subtypes at a very early stage. Current data-driven approaches can be used to classify subtypes during later stages of AD or related disorders, but making predictions in the asymptomatic or prodromal stage is challenging. Furthermore, the classifications of most existing models lack explainability, and these models rely solely on a single modality for assessment, limiting the scope of their analysis. Thus, we propose a multimodal framework that utilizes early-stage indicators, including imaging, genetics, and clinical assessments, to classify AD patients into progression-specific subtypes at an early stage. In our framework, we introduce a tri-modal co-attention mechanism (Tri-COAT) to explicitly capture cross-modal feature associations. Data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) (slow progressing = 177, intermediate = 302, and fast = 15) were used to train and evaluate Tri-COAT using a 10-fold stratified cross-testing approach. Our proposed model outperforms baseline models and sheds light on essential associations across multimodal features supported by known biological mechanisms. The multimodal design behind Tri-COAT allows it to achieve the highest classification area under the receiver operating characteristic curve while simultaneously providing interpretability to the model predictions through the co-attention mechanism.

Characterization of PEGylation sites in Neulasta and a biosimilar candidate with a combined fragmentation strategy in mass spectrometry analysis.

In the development of biosimilar products to Neulasta, it is essential to determine the intact molecular mass and confirm precise PEGylation sites. In this study, we applied a combination of techniques, including post-column addition of triethylamine in reversed-phase liquid chromatography-mass spectrometry (RPLC-MS) to determine the intact molecular mass, and in-source fragmentation (ISF) and higher-energy collision dissociation-tandem mass spectrometry (HCD-MS/MS) to identify the PEGylation site. Our results show that both the pegfilgrastim biosimilar candidate and Neulasta lots are mono-PEGylated at the N-terminal end. Furthermore, we show that the combined ISF and HCD-MS/MS method can be used for identifying the PEGylation sites in the diPEGylated variant of pegfilgrastim. The diPEGylated variant has modification sites at the N-terminal end and a lysine at position 35 in the protein sequence.

Reducción de la infección por Helicobacter pylori en pacientes derivados a endoscopia digestiva alta en Santiago de Chile entre 2010-2020 / Reduction in Helicobacter pylori infection among patients referred for upper gastrointestinal endoscopy in Santiago, Chile, between 2010-2020

RESUMEN Latinoamérica presenta una alta prevalencia de infección por Helicobacter pylori (Hp). Entre 1996-2003 la prevalencia en Santiago de Chile fue del 70%; estudios recientes presentan una disminución en esta infección. Actualizar la frecuencia de Hp es fundamental debido a su impacto en la salud asociado. Objetivo: Nuestro objetivo fue describir la tendencia de la infección por Hp en pacientes que asisten a endoscopía digestiva alta (EDA) ambulatoria en una población chilena. Materiales y métodos: Se realizó un estudio observacional retrospectivo de pacientes mayores de 18 años que asistieron a una primera EDA con test rápido de ureasa entre 2010-2020. La tendencia en el tiempo fue descrita mediante análisis de series de tiempo. Se construyó un modelo Poisson para estimar el riesgo de infección, ajustado por edad y sexo. Resultados: Se incluyeron 11 355 pacientes [66,9% mujeres; edad media 52 años; Hp 41,6%]. El sexo masculino presentó una mayor frecuencia de infección por Hp [RR 1,13; (IC95%:1,08-1,18)]. La frecuencia de Hp disminuyó significativamente desde 45,1% en 2010 hasta 29% en 2020, con 36% menor probabilidad de presentar infección por Hp en 2020 con respecto al 2010 [RR 0,64; (IC95%:0,55-0,74)]. Se proyectó un descenso progresivo en la tendencia de infección por Hp hasta valores cercanos al 25% para el año 2025. Conclusión: Se observó una reducción significativa en la infección por Hp entre los años 2010-2020. Esta disminución pudiese ser explicada mediante la incorporación de políticas públicas de salud en la última década asociadas a cambios sociosanitarios.

ABSTRACT Latin America presents a high prevalence of Helicobacter pylori (Hp) infection. Between 1996-2003, the prevalence in Santiago, Chile, was 70%; recent studies indicate a decrease in this infection. Updating the frequency of Hp is crucial due to its associated health impact. Objective: Our objective was to describe the trend in Hp infection in patients undergoing ambulatory esophagogastroduodenoscopy (EGD) in a Chilean population. Materials and methods: A retrospective observational study was conducted on patients over 18 years old who attended a first EGD with a rapid urease test between 2010-2020. Time trends were described through time series analysis. A Poisson model was constructed to estimate the risk of infection, adjusted for age and gender. Results: 11,355 patients were included [66.9% females; mean age 52 years; Hp 41.6%]. Male gender presented a higher frequency of Hp infection [RR 1.13; (95% CI: 1.08-1.18)]. Hp frequency infection decreased significantly from 45.1% in 2010 to 29% in 2020, with a 36% lower probability of Hp infection in 2020 compared to 2010 [RR 0.64; (95% CI: 0.55-0.74)]. A progressive decline in Hp infection trend was projected, reaching values close to 25% by year 2025. Conclusion: A significant reduction in Hp infection was observed between 2010-2020. This decrease could be explained by the implementation of public health policies in the last decade associated with socio-sanitary changes.

An acute lymphoblastic leukemia cell-based preclinical assay revealed functional differences between commercial brands of L-asparaginase administered in Colombia.

BACKGROUND: L-asparaginase (L-ASNase) is an essential component of chemotherapy strategies due to its differential action between normal and leukemic cells. Recently, concerns about the efficiency of commercial formulations administered in developing countries have been reported, and available methods have limitations for directly determining the quality of the formulation of the medications. PROCEDURE: We developed a cell-based protocol to analyze the activity of different L-ASNase formulations used in Colombia to induce apoptosis of the NALM-6 cell line after 24, 48, and 72 hours, using flow cytometry. Then we compared results and determined the statistically significant differences. RESULTS: Three statistically different groups, ranging from full to no activity against leukemic cells, using 0.05, 0.5, and 5.0 IU/ml concentrations, were identified. Group 1 (asparaginase codified [ASA]2-4) exhibited very low to no activity against B-cell acute lymphoblastic leukemia (B-ALL) cells. Group 2 (ASA6) exhibited intermediate-level activity, and group 3 (ASA1 and ASA5) exhibited high activity. CONCLUSIONS: Differences found between the therapeutic formulations of L-ASNase distributed in Colombia raise concerns about the quality of the treatment administered to patients in low- and middle-income countries. Therefore, we recommend a preclinical evaluation of formulations of L-ASNase in order to prevent therapeutical impacts on the outcome of ALL patients.

FairPRS: adjusting for admixed populations in polygenic risk scores using invariant risk minimization.

Polygenic risk scores (PRS) are increasingly used to estimate the personal risk of a trait based on genetics. However, most genomic cohorts are of European populations, with a strong under-representation of non-European groups. Given that PRS poorly transport across racial groups, this has the potential to exacerbate health disparities if used in clinical care. Hence there is a need to generate PRS that perform comparably across ethnic groups. Borrowing from recent advancements in the domain adaption field of machine learning, we propose FairPRS - an Invariant Risk Minimization (IRM) approach for estimating fair PRS or debiasing a pre-computed PRS. We test our method on both a diverse set of synthetic data and real data from the UK Biobank. We show our method can create ancestry-invariant PRS distributions that are both racially unbiased and largely improve phenotype prediction. We hope that FairPRS will contribute to a fairer characterization of patients by genetics rather than by race.

High prevalence of SARS-CoV-2 detection and prolonged viral shedding in stools: A systematic review and cohort study / Elevada detección de SARS-CoV-2 y prolongada excreción viral en deposiciones: Estudio de cohorte y revisión sistemática

Objectives: To: 1. Describe the frequency of viral RNA detection in stools in a cohort of patients infected with SARS-CoV-2, and 2. Perform a systematic review to assess the clearance time in stools of SARS-CoV-2. Methods: We conducted a prospective cohort study in two centers between March and May 2020. We included SARS-CoV-2 infected patients of any age and severity. We collected seriated nasopharyngeal swabs and stool samples to detect SARS-CoV-2. After, we performed a systematic review of the prevalence and clearance of SARS-CoV-2 in stools (PROSPERO-ID: CRD42020192490). We estimated prevalence using a random-effects model. We assessed clearance time by using Kaplan–Meier curves. Results: We included 32 patients; mean age was 43.7±17.7 years, 43.8% were female, and 40.6% reported gastrointestinal symptoms. Twenty-five percent (8/32) of patients had detectable viral RNA in stools. The median clearance time in stools of the cohort was 11[10–15] days. Systematic review included 30 studies (1392 patients) with stool samples. Six studies were performed in children and 55% were male. The pooled prevalence of viral detection in stools was 34.6% (twenty-four studies, 1393 patients; 95%CI:25.4–45.1); heterogeneity was high (I2:91.2%, Q:208.6; p≤0.001). A meta-regression demonstrates an association between female-gender and lower presence in stools (p=0.004). The median clearance time in stools was 22 days (nineteen studies, 140 patients; 95%CI:19–25). After 34 days, 19.9% (95%CI:11.3–29.7) of patients have a persistent detection in stools. Conclusions: Detection of SARS-CoV-2 in stools is a frequent finding. The clearance of SARS-CoV-2 in stools is prolonged and it takes longer than nasopharyngeal secretions.(AU)

Objetivos: 1. Evaluar la detección de ARN viral en deposiciones y su tiempo de excreción en una cohorte de pacientes con SARS-CoV-2; 2. Realizar una revisión sistemática para evaluar el tiempo de excreción en deposiciones del SARS-CoV-2. Métodos: Estudio de cohorte prospectiva en dos centros entre marzo-mayo del 2020. Incluimos pacientes infectados con SARS-CoV-2 de cualquier edad y gravedad. Recolectamos secreciones nasofaríngeas y deposiciones en forma seriada para detectar SARS-CoV-2. También realizamos una revisión sistemática de la prevalencia y excreción del SARS-CoV-2 en deposiciones (PROSPERO-ID: CRD42020192490). Estimamos la prevalencia usando un modelo de efectos aleatorios. Evaluamos el tiempo de excreción usando curvas Kaplan-Meier. Resultados: Incluimos 32 pacientes; edad media 43 ± 17,7 años, 43,8% eran mujeres y 40,6% reportaron síntomas gastrointestinales. Veinticinco por ciento (8/32) tenían ARN viral detectable en deposiciones. La mediana de excreción en deposiciones fue 11 [10-15] días. La revisión sistemática incluyó 30 estudios (1.392 pacientes) con muestras en deposiciones. Seis estudios fueron realizados en niños y 55% eran hombres. La prevalencia estimada de detección viral en deposiciones fue de 34,6% (24 estudios, 1.393 pacientes; IC 95%: 25,4-45,1); la heterogeneidad fue elevada (I2: 91,2%; Q: 208,6; p ≤ 0,001). Una metarregresión demostró una asociación entre el género femenino y menor prevalencia en deposiciones (p = 0,004). La mediana de tiempo de excreción fueron 22 días (19 estudios, 140 pacientes; IC 95%: 19-25). Tras 34 días, 19,9% (IC 95%: 11,3-29,7) de los pacientes tenían detección persistente en deposiciones. Conclusiones: La detección de SARS-CoV-2 en deposiciones es un hallazgo frecuente. La excreción del SARS-CoV-2 en deposiciones es prolongada y es más tardía que en secreciones nasofaríngeas.(AU)

Terapias cuádruples son superiores a terapia triple estándar en primera línea de erradicación de Helicobacter pylori en Chile / Quadruple therapies are superior to standard triple therapy for Helicobacter pylori first-line eradication in Chile

Introducción: La infección por Helicobacter pylori afecta aproximadamente al 70% de la población chilena. Es un problema de salud pública cuyo tratamiento de erradicación forma parte de políticas públicas en Chile. Objetivos: Caracterizar los esquemas de erradicación de primera línea de H. pylori más utilizados en nuestro medio y evaluar su eficacia. Métodos: Se realizó un estudio observacional retrospectivo donde, en pacientes con infección por H. pylori certificada, se evaluó el esquema de erradicación indicado por el médico tratante, su eficacia, adherencia y efectos adversos. Resultados: Se analizaron 242 pacientes y 4 esquemas de erradicación; terapia triple estándar, terapia dual, concomitante y cuadriterapia con bismuto. Se observaron tasas de erradicación de 81,9% (IC 95% 74,44-87,63), 88,5% (IC 95% 73,13-95,67), 93,7% (IC 95% 78,07-98,44) y 97,6% (IC 95% 84,81-99,67) respectivamente, siendo más eficaces la terapia concomitante (RR: 1,14; IC 95% 1,01-1,29; p=0,028) y cuadriterapia con bismuto (RR: 1,19; IC 95% 1,09-1,31; p<0,001) que la triple terapia estándar. La tasa de efectos adversos reportados fue de 58,5% (IC 95% 50,66-65,92), 35,4% (IC 95% 24,6-48,11), 22,9% (IC 95% 11,81-37,14) y 63,4% (IC 95% 47,8-76,64), para la terapia triple estándar, dual, concomitante, y cuádruple con bismuto, respectivamente. La terapia dual y concomitante tuvieron menos efectos adversos en comparación con la terapia estándar. Conclusiones: Las cuadriterapias son superiores a la triple terapia estándar por lo que deberían ser consideradas como tratamiento de primera línea en Chile. La terapia dual es promisoria. Más estudios serán requeridos para determinar qué esquemas son más costo-efectivos.(AU)

Introduction: Helicobacter pylori infection affects approximately 70% of the Chilean population. It is a public health problem whose eradication treatment is part of the explicit health guarantees in Chile. Objectives: Characterize the most widely used H. pylori first-line eradication therapies in our environment and evaluate their efficacy. Methods: A retrospective observational study was carried out where, in patients with certified H. pylori infection, the eradication therapy indicated by the treating physician, its efficacy, adherence and adverse effects, in addition to the eradication certification method used, were evaluated. Results: 242 patients and 4 main therapies were analyzed: standard triple therapy, dual therapy, concomitant therapy, and bismuth quadruple therapy. Eradication rates of 81.9% (95% CI 74.44–87.63), 88.5% (95% CI 73.13–95.67), 93.7% (95% CI 78.07–98.44) and 97.6% (95% CI 84.81–99.67) were observed respectively, with concomitant therapy (RR: 1.14; 95% CI 1.01–1.29; p=.028) and quadruple therapy with bismuth (RR: 1.19; 95% CI 1.09–1.31; p<.001) being significantly more effective than standard triple therapy. Regarding the rate of reported adverse effects, it was 58.5% (95% CI 50.66–65.92), 35.4% (95% CI 24.6–48.11), 22.9% (95% CI 81–37.14) and 63.4% (95% CI 47.8–76.64), having the dual and concomitant therapy significantly fewer adverse effects compared with standard therapy. Conclusions: Quadruple therapies are superior to standard triple therapy and should be considered as first-line treatment in Chile. Dual therapy is promising. More studies will be required to determine which therapies are most cost-effective.(AU)