Causality between six psychiatric disorders and digestive tract cancers risk: a two-sample Mendelian randomization study.

Associations between psychiatric disorders and digestive tract cancers have been proposed. However, the causal link between these factors remains unclear. This study pioneers Mendelian randomization (MR) analysis to explore the genetic link between psychiatric disorders and digestive tract cancers risk. We analysed data on six psychiatric disorders [schizophrenia, bipolar disorder, major depressive disorder (MDD), attention deficit hyperactivity disorder, autism spectrum disorder, and panic disorder (PD)] and digestive tract cancers [esophagus cancer (EC), gastric cancer (GC), and colorectal cancer (CRC)] from genome-wide association studies databases. Using instrumental variables identified from significant single nucleotide polymorphism associations, we employed the inverse variance weighted (IVW) method alongside the weighted median (WM) method and MR-Egger regression. The results revealed no causal link between psychiatric disorders and the risk of EC or GC. Psychiatric disorders were not identified as risk factors for CRC. Notably, PD demonstrated a lower CRC risk (OR = 0.79, 95% CI 0.66-0.93, P = 0.01). This MR analysis underscores the lack of a causal association between psychiatric disorders and digestive tract cancers risk while suggesting a potential protective effect of PD against CRC.

Isotopic Constraints on Sources and Transformations of Nitrate in the Mount Everest Proglacial Water.

Glacier melting exports a large amount of nitrate to downstream aquatic ecosystems. Glacial lakes and glacier-fed rivers in proglacial environments serve as primary recipients and distributors of glacier-derived nitrate (NO3-), yet little is known regarding the sources and cycling of nitrate in these water bodies. To address this knowledge gap, we conducted a comprehensive analysis of nitrate isotopes (δ15NNO3, δ18ONO3, and Δ17ONO3) in waters from the glacial lake and river of the Rongbuk Glacier-fed Basin (RGB) in the mountain Everest region. The concentrations of NO3- were low (0.43 ± 0.10 mg/L), similar to or even lower than those observed in glacial lakes and glacier-fed rivers in other high mountain regions, suggesting minimal anthropogenic influence. The NO3- concentration decreases upon entering the glacial lake due to sedimentation, and it increases gradually from upstream to downstream in the river as a soil source is introduced. The analysis of Δ17ONO3 revealed a substantial contribution of unprocessed atmospheric nitrate, ranging from 34.29 to 56.43%. Denitrification and nitrification processes were found to be insignificant in the proglacial water of RGB. Our study highlights the critical role of glacial lakes in capturing and redistributing glacier-derived NO3- and emphasizes the need for further investigations on NO3- transformation in the fast-changing proglacial environment over the Tibetan Plateau and other high mountain regions.

Real-world outcomes of anti-vascular endothelial growth factor therapy for retinal vascular vein occlusion in Tibet, China.

AIM: To evaluate the outcomes of intravitreal anti-vascular endothelial growth factor (anti-VEGF) agents for patients with retinal vein occlusion (RVO) related-macular edema (ME) in Tibetan. METHODS: A retrospective, observational, single-center study. The demographic and clinical data of 90 RVO Tibetan patients (93 eyes) treated with either ranibizumab or conbercept in Tibet Autonomous Region People's Hospital from Jan 2018 to December 2019 were collected. RESULTS: The mean patient age was 56.8±10.6y, 45 (50%) of them were female. The mean living altitude was 3867.8±567.9 m. At the last visit, the best-corrected visual acuity (BCVA) significantly increased (52.2±21.8 letters) in comparison with the baseline (38.2±24.1 letters, P<0.001); while the central retinal thickness (CRT) significantly reduced (245.5±147.6 µm) in comparison with the baseline (504.1±165.2 µm, P<0.001). The 43.0% of the eyes gained ≥15 letters, 60.2% of the eyes gained ≥10 letters, and 78.5% of the eyes gained ≥5 letters. No vision loss was noted in 92.5% of the eyes, 4 eyes lost more than 10 letters during follow-up period. The mean number of injections was 2.4±1.8. No severe ocular or systemic adverse events related to either the drug or injection were noted. CONCLUSION: Anti-VEGF therapy is effective and safe in Tibetan patients for the treatment of RVO related ME.