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Weakening of the Summer Monsoon Over the Past 150 Years Shown by a Tree-Ring Record From Shandong, Eastern China, and the Potential Role of North Atlantic Climate
No full textThe causes of the decreased intensity of the East Asian summer monsoon (EASM) over the past 150 years are still not fully understood, although several studies have linked the monsoon weakening to the warming of tropical oceans. Here, we use pine tree-rings to reconstruct the precipitation total for April-August from 1810 to 2018, in south-central Shandong Province, in the EASM region. The reconstruction accounts for 41.8% of the instrumental precipitation variance during 1965-2018. The EASM precipitation reconstruction shows extreme pluvial conditions in 1832, 1833, 1886, and 1998, and extreme droughts in 1878, 1901, and 1910, which correspond precisely to extreme climatic events recorded in historical documents. The reconstructed precipitation reveals a drying trend since the 1870s, which matches well with the decreasing trend of the EASM inferred from stalagmite oxygen isotope (d(18)O) records and climate simulations. The trend of decreasing precipitation since the 1870s, indicated by our reconstruction, is significantly correlated with the spring sea surface temperature (SST) of the North Atlantic Ocean, which suggests that the EASM weakening was linked to North Atlantic SST variations during the past 150 years. This potential role of North Atlantic SST variability is supported by climate sensitivity simulations of the Community Earth System Model. North Atlantic SST variability induces two teleconnections of Rossby-like wave propagation from the North Atlantic into East Asia, resulting in anomalous precipitation in this region.This work was supported by the National Natural Science Foundation (32061123008),~the National Key R&D Program of China, Ministry of Science and Technology of the People's Republic of China(2018YFA0606401)
Whole-exome sequencing of oral epithelial dysplasia samples reveals an association with new genes
No full textThe genetic basis of oral epithelial (OED) is unknown, and there is no reliable method for evaluating the risk of malignant transformation. Somatic mutations are responsible for the transformation of dysplastic mucosa to invasive cancer. In addition, these genomic variations could represent objective markers of the potential for malignant transformation. We performed whole-exome sequencing of 10 OED samples from Brazilian and Chilean patients. Using public genetic repositories, we identified 41 deleterious variants that could produce high-impact changes in the amino acid structures of 38 genes. In addition, the variants were filtered according to normal skin and Native American genome profiles. Finally, 13 genes harboring 15 variants were found to be exclusively related to OED. High-grade epithelial dysplasia samples showed a tendency to accumulate highly deleterious variants. We observed that 62% of 13 OED genes identified in our study were also found in head and neck squamous cell carcinoma. Among the shared genes, eight were not identified in oral squamous cell carcinoma. To our knowledge, we have described for the first time 13 genes that are found in OED in a Latin American population, of which five genes have already been observed in oral squamous cell carcinoma. Through this study, we identified genes that may be related to basal biological functions in OED.All procedures performed in this study were in accordance with the ethical standards of the Scholl Dentistry of the University of Chile (Approval No. 2014/29) committee and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards. The patients were not directly involved in this study. Funding: FONDECYT no 11140281 (Ricardo Fernandez-Ramires), Centro Ciencia & Vida, FB210008, Financiamiento Basal para Centros Cientificos y Tecnologicos de Excelencia de ANID
Does substance use disorder treatment completion reduce the risk of treatment readmission in Chile?
No full textBackground: Recovery from substance use disorders (SUD) often entails multiple treatment episodes, which clashes with a context of a treatment system with limited resources and long waiting. Treatment retention and completion have been pointed out as key elements for sustainable achievement; however, most of the evidence generated focuses on opioids and injected substances, which is hardly transferable to the Latin American context.Objectives: This study aims to estimate the effect of SUD treatment completion on the risk of being readmitted to a SUD treatment in Chile.Methods: We conducted a retrospective analysis on a database of 107,559 treatment episodes from 85,048 adult patients admitted to SUD treatment during 2010-2019 in Chile. We adjusted two separate Prentice Williams and Petersen Gap Time models, to explore the association between treatment completion (vs. non-completion) and up to the third treatment readmission among residential and ambulatory modalities while controlling for time-varying covariates. To examine whether the effect of treatment completion differs between events, we included an interaction term with the stratification variable.Results: We found that completing the treatment cuts readmission risk for the first event by 17% (Average Hazard Ratio [95% CI] = 0.83 [0.78, 0.88]) and by 14% for the second entry (Average Hazard Ratio [95% CI] = 0.86 [0.78, 0.94]) in ambulatory treatments. We did not find evidence that completing a treatment reduces the readmission risk for residential treatments or third attempts in ambulatory ones. Conclusion: Treatment completion was associated with benefits in cutting readmission risk for the first and second episodes in ambulatory treatments among Chilean adults. It is important to explore different mechanisms than treatment retention for residential treatments.This work was supported by FONDECYT Regular No. 1191282 and from ANID - Millennium Science Initiative Program, no. NCS2021_003 and no. NCS2021_013. TRJ was funded by FONDECYT de Iniciacion No. 11200486
Aromatic Bromination Abolishes Deficits in Visuospatial Learning Induced by MDMA ("Ecstasy") in Rats While Preserving the Ability to Increase LTP in the Prefrontal Cortex
No full textIt has recently been demonstrated that aromatic bromination at C(2) abolishes all typical psychomotor, and some key prosocial effects of the entactogen MDMA in rats. Nevertheless, the influence of aromatic bromination on MDMA-like effects on higher cognitive functions remains unexplored. In the present work, the effects of MDMA and its brominated analog 2Br-4,5-MDMA (1 mg/kg and 10 mg/kg i.p. each) on visuospatial learning, using a radial, octagonal Olton maze (4 x 4) which may discriminate between short-term and long-term memory, were compared with their influence on in vivo long-term potentiation (LTP) in the prefrontal cortex in rats. The results obtained indicate that MDMA diminishes both short- and long-term visuospatial memory but increases LTP. In contrast, 2Br-4,5-MDMA preserves long-term visuospatial memory and slightly accelerates the occurrence of short-term memory compared to controls, but increases LTP, like MDMA. Taken together, these data are consistent with the notion that the modulatory effects induced by the aromatic bromination of the MDMA template, which abolishes typical entactogenic-like responses, might be extended to those effects affecting higher cognitive functions, such as visuospatial learning. This effect seems not to be associated with the increase of LTP in the prefrontal cortex
Exchanging Screen For Non Screen Sitting Time Or Physical Activity Might Attenuate Depression And Anxiety: A Cross Sectional Isotemporal Analysis During Early Pandemics In South America
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Hyperbaric Oxygen Treatment Increases Intestinal Stem Cell Proliferation Through The M Torc1/S6 K1 Signaling Pathway In
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