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Background: Thyroid hormones significantly influence cardiovascular pathophysiology, yet their prognostic role in acute aortic dissection (AAD) remains inadequately explored. This study assesses the prognostic value of thyroid hormone levels in AAD, focusing on the mediating roles of renal function and coagulation. Methods: We included 964 AAD patients in this retrospective cohort study. Utilizing logistic regression, restricted cubic splines, and causal mediation analysis, we investigated the association between thyroid hormones and inhospital mortality and major adverse cardiovascular events (MACEs). Results: In AAD patients overall, an increase of one standard deviation in FT4 levels was associated with a 31.9% increased risk of MACEs (OR 1.319; 95% CI 1.098-1.584) and a 36.1% increase in in-hospital mortality (OR 1.361; 95% CI 1.095-1.690). Conversely, a higher FT3/FT4 ratio was correlated with a 20.2% reduction in risk of MACEs (OR 0.798; 95% CI 0.637-0.999). This correlation was statistically significant predominantly in Type A AAD, while it did not hold statistical significance in Type B AAD. Key renal and coagulation biomarkers, including blood urea nitrogen, creatinine, cystatin C, prothrombin time ratio, prothrombin time, and prothrombin time international normalized ratio, were identified as significant mediators in the interplay between thyroid hormones and MACEs. The FT3/FT4 ratio exerted its prognostic influence primarily through the mediation of renal functions and coagulation, while FT4 levels predominantly impacted outcomes via a partial mediation effect on coagulation. Conclusion: FT4 levels and the FT3/FT4 ratio are crucial prognostic biomarkers in AAD patients. Renal function and coagulation mediate the association between the thyroid hormones and MACEs. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the role and mechanism of long non-coding RNA (lncRNA) HIF1A antisense RNA 2 (HIF1A-AS2) in regulating imatinib (IM) resistance in gastrointestinal stromal tumor (GIST) cells under hypoxia. The expression of HIF1A-AS2 was silenced by siRNA in GIST cells. Cytotoxicity, apoptosis, and autophagy were evaluated under normoxic and hypoxic conditions. The expression levels of HIF1A-AS2, HIF1A, apoptosis-associated genes, and autophagy-associated genes were determined by qRT-PCR analysis and western blot. We found that lncRNA HIF1A-AS2 was highly expressed in GIST tissues and cells. Knockdown of HIF1A-AS2 increased the sensitivity of GIST cells to IM and increased apoptosis. Moreover, a hypoxic environment decreased the sensitivity of GIST cells to IM, and the knockdown of HIF1A-AS2 reversed this effect. Mechanistically, the knockdown of HIF1A-AS2 inhibited IM-mediated autophagy. Finally, HIF1A was found to positively regulate HIF1A-AS2 under hypoxic conditions. Collectively, these data demonstrate that hypoxia-induced HIF1A-AS2 promotes IM resistance in GIST cells by regulating autophagy. [ABSTRACT FROM AUTHOR]

Introduction: Acute ischemic stroke (AIS) is a disease with high morbidity and mortality in the clinic. The current experiments aimed to study the effects of UCA1 interfering miR-18a-5p on cerebral ischemia-reperfusion (CI/R). Material and methods: For rat models undergoing middle cerebral artery infarction (MCAO) surgery, the expression of UCA1 and miR-18a-5p was evaluated by qRT-PCR, and underlying function was identified by detecting infarct size, neurological scores, and inflammation. Luciferase report was applied to verify the relationship between UCA1 and miR-18a-5p. In the cell models, the impacts of UCA1 and miR-18a-5p were validated by CCK-8 assay, flow cytometry analysis, and ELISA. In patients with AIS, Pearson correlation was carried out to unveil the association between UCA1 and miR-18a-5p. Results: The expression of UCA1 was at high levels and miR-18a-5p was at low levels in AIS patients. UCA1 knockdown showed a protective role in infarct size, neurofunction, and inflammation via binding miR-18a-5p. MiR-18a-5p participated in the regulation of UCA1 on cell viability, cell apoptosis, lactate dehydrogenase (LDH) levels, and inflammation. In patients with AIS, overexpression of UCA1 and underexpression of miR-18a-5p had a reverse correlation. Conclusions: Elimination of UCA1 was favourable to the recovery of the rat model and cells from CI/R damage by efficaciously sponging miR-18a-5p. [ABSTRACT FROM AUTHOR]

Ginsenoside Rb1 (GRb1), which is one of the main ingredients derived from Panax ginseng, has been widely used to treat various gastrointestinal disorders. The present study aimed to determine whether GRb1 was able to prevent intestinal mucosal barrier damage in rats following peritoneal air exposure for 3 h. GRb1 (5, 10, and 20 mg/kg) was orally administrated via gavage four times prior to and following surgery. Blood and terminal ileum were sampled 24 h following surgery. Levels of serum D-lactate (D-LA) were detected using an enzyme-linked immunosorbent assay kit. Intestinal permeability was assessed by determining the intestinal clearance of fluorescein isothiocyanate-dextran (FD4). Activity of intestinal myeloperoxidase was measured to assess intestinal inflammation, and intestinal histopathology was assessed by light microscopy. The results showed that GRb1 reduced the level of serum D-LA, intestinal clearance of FD4, and the activity of intestinal myeloperoxidase. Intestinal edema and inflammation were also ameliorated by GRb1, and the Chiu's scores employed for assessing intestinal mucosal damage were also reduced in the GRb1-treated peritoneal air exposure group. In addition, GRb1 induced a significant difference at 10 and 20 mg/kg, indicating a dose-dependent effect. The results of the present study suggest that GRb1 may be able to protect the intestinal mucosal barrier against damage induced by peritoneal air exposure, which may be associated with its anti-inflammatory action. [ABSTRACT FROM AUTHOR]

Abstract: Three days old cucumber (Cucumis sativus L.) was grown in a factorial design under two levels of water condition (well watered and drought) and two supplemental levels of ultraviolet-B(280-320 nm) irradiance(0, 0.24, 0.42 W/m[sup 2]) for 30 days. Plants were grown in a greenhouse under visible light with 400 Mu mol/(m[sup 2] x s), day-night temperature 32/20 Celsius and relative humidity 70 +/- 10%. The combination of UV-B radiation and water stress resulted in the decrease in plant height, leaf area ratio and relative growth rate, and increase in specific leaf mass and net assimilation rate. There was almost no effect of ultraviolet-B radiation on the contents of chlorophyll a and b under water stress. However, interactive effects of ultraviolet-B radiation and water conditions on the content of anthocyanin were much great. UV-B irradiance with water stress also caused a reduction in net photosynthesis, apparent quantum efficiency, gas exchange and stomatal resistance, and an increase in evaporation. [ABSTRACT FROM AUTHOR]

This work reports a bioinspired anisotropic nanocomposite by polar solution assisted mechanical stretching method, consisting of polyvinyl alcohol (PVA) and silicon carbide nanowires (SiCNWs) with aligned morphology in one direction. Inspired by the structural mimicry of myofibers, in which the uniaxial mechanical property of materials can be improved evidently, highly-aligned SiCNWs and PVA chains that interact using intermolecular force can be obtained. Hysteresis is observed and reversible deformation occurs while tensile–relaxation cycles are applied to the 100% stretched SiCNWs/PVA nanocomposites. The nanocomposites exhibit excellent properties and the tensile strength of 100% stretched SiCNWs/PVA nanocomposites is 188.30 ± 4.2 MPa and elastic modulus is 6.95 GPa, which are increased by 421.90% and 581.37% compared with pure PVA. Finite element simulation of fracture mechanism shows good agreement with the experimental results. An improvement of thermal conductivity is also achieved in well-aligned SiCNWs/PVA. The work imitates the structure of mammal muscle and also has great potential for the macroscopic application of one-dimensional nanomaterials as super flexible heat dissipation materials. [ABSTRACT FROM AUTHOR]