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131.
132.

Background

Studies from high-income countries have shown that women receive less aggressive diagnostics and treatment than men in acute coronary syndromes (ACS), though their short-term mortality does not appear to differ from men. Data on gender differences in ACS presentation, management, and outcomes are sparse in India.

Methods and Results

The Detection and Management of Coronary Heart Disease (DEMAT) Registry collected data from 1,565 suspected ACS patients (334 women; 1,231 men) from ten tertiary care centers throughout India between 2007–2008. We evaluated gender differences in presentation, in-hospital and discharge management, and 30-day death and major adverse cardiovascular event (MACE; death, re-hospitalization, and cardiac arrest) rates. Women were less likely to present with STEMI than men (38% vs. 55%, p<0.001). Overall inpatient diagnostics and treatment patterns were similar between men and women after adjustment for potential confounders. Optimal discharge management with aspirin, clopidogrel, beta-blockers, and statin therapy was lower for women than men, (58% vs. 65%, p = 0.03), but these differences were attenuated after adjustment (OR = 0.86 (0.62, 1.19)). Neither the outcome of 30-day mortality (OR = 1.40 (0.62, 3.16)) nor MACE (OR = 1.00 (0.67, 1.48)) differed significantly between men and women after adjustment.

Conclusions

ACS in-hospital management, discharge management, and 30-day outcomes did not significantly differ between genders in the DEMAT registry, though consistently higher treatment rates and lower event rates in men compared to women were seen. These findings underscore the importance of further investigation of gender differences in cardiovascular care in India.  相似文献   
133.
Over the past decades the role of nitric oxide (NO) and reactive oxygen species (ROS) in signaling and cellular responses to stress has witnessed an exponential trend line. Despite advances in the subject, our knowledge of the role of NO and ROS as regulators of stress and plant growth and their implication in signaling pathways is still partial. The crosstalk between NO and ROS during root formation offers new domains to be explored, as it regulates several plant functions. Previous findings indicate that plants utilize these signaling molecules for regulating physiological responses and development. Depending upon cellular concentration, NO either can stimulate or impede root system architecture (RSA) by modulating enzymes through post-translational modifications. Similarly, the ROS signaling molecule network, in association with other hormonal signaling pathways, control the RSA. The spatial regulation of ROS controls cell growth and ROS determine primary root and act in concert with NO to promote lateral root primordia. NO and ROS are two central messenger molecules which act differentially to upregulate or downregulate the expression of genes pertaining to auxin synthesis and to the configuration of root architecture. The investigation concerning the contribution of donors and inhibitors of NO and ROS can further aid in deciphering their role in root development. With this background, this review provides comprehensive details about the effect and function of NO and ROS in the development of RSA.  相似文献   
134.
Protoplasma - Absorption of excess excitation energy induces overproduction of singlet oxygen (1O2) in plants. The major sources of singlet oxygen production are chlorophyll and its intermediates...  相似文献   
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Kumar  Alok  Kalita  J.  Sinha  Rohit A.  Singh  Gajendra  B  Anjum  Shukla  Mukti  Tiwari  Swasti  Dhole  T. N.  Misra  U. K. 《Neurochemical research》2020,45(9):2184-2195
Neurochemical Research - Role of autophagy in Japanese encephalitis viral (JEV) infection is not well known. In the present study, we reported the role of autophagy flux in microglia activation,...  相似文献   
138.

Alzheimer’s disease pathogenesis is measured by two key hallmarks viz extracellular senile plaques composed of insoluble amyloid beta (Aβ) and neurofibrillary tangles composed of hyperphosphorylated tau, resulting in microtubule destabilization, synaptic damage and neurodegeneration. Accumulation of Aβ is an introducing pathological incident in Alzheimer’s disease; hence, the effect of dimethyl fumarate (DMF) on Aβ1-42-induced alterations in phosphorylated tau, related protein kinases, fibrillogenesis and microtubule assembly in neuroblastoma SH-SY5Y cells was determined. DMF attenuated Aβ1-42-induced neuronal apoptosis by down-regulating protein levels of Bcl-2/Bax, cleaved caspase-3 and caspase-9. Aβ1-42-induced upsurge in tau phosphorylation at Ser396 and Thr231 epitopes was found to be declined by DMF pretreatment. The upregulated activity of glycogen synthase kinase-3 beta (GSK-3β) by Aβ1?42 treatment was blocked by DMF pretreatment. PI3K substrate Akt (at Ser473) as well as Wnt dependent β-catenin and cyclin D1 activity was found to be upregulated by DMF pretreatment in Aβ1-42 treated cells. ThT fluorescence and MTT assay showed that DMF reduces Aβ fibrillogenesis and inhibit related cytotoxicity. Also, DMF exerts a protective effect on Aβ1-42-induced microtubule disassembly caused due to a reduction in polymerized β3-and α-tubulin. These results indicate that down-regulation of GSK-3β activity and subsequent activation of PI3K/Akt and Wnt/β-catenin signaling pathways are closely involved in the shielding effect of DMF against Aβ1-42-induced tau hyperphosphorylation. Modulating cellular events related to Aβ1-42-induced tau hyperphosphorylation, aggregation and microtubule stabilization offers new molecular insights into the defensive outcome of DMF towards appropriate management for Alzheimer’s disease.

  相似文献   
139.
Abstract

This study identifies and validates hexokinase type 4 (HK4), an isozyme of hexokinase in the liver and pancreas, as an important target of C2-β-D-glucopyranosyl-1,3,6,7-tetrahydroxyxanthone (βdGT), a xanthone glucoside suggested to have antidiabetic property. In the study, we applied the computational pipeline of molecular docking followed by the molecular dynamics simulations to shortlist potential βdGT protein targets. The analysis of protein dynamics and the binding free energy (ΔG) led us to the identification of HK4 as a key βdGT target, whereby the binding mode and domain dynamics suggested the activator function of βdGT. βdGT bound to the allosteric site of the isozyme ~13?Å away from the substrate (glucose)-binding site. The binding free energy of the ligand-protein complex was energetically feasible (ΔG, –41.61?kcal/mol) and the cleft angle deviation between the two (small and large) domains of HK4 revealed differential HK4 dynamics in response to βdGT binding. 3D structure analysis of the isozyme-ligand complex highlighted the role of Arg63, Glu67 and Lys458 in ligand stabilization and hydrophobic interactions mediated by Tyr214 and Met235. Experimental validation of the results of computational analysis confirmed the activator function of βdGT on HK4. The study has implication in diabetes as βdGT may be used to lower the blood glucose level by activating hepatic and pancreatic hexokinase without the risk of hypoglycemia.

Communicated by Ramaswamy H. Sarma  相似文献   
140.
Mouse embryonic stem cells (mESCs) display unique mechanical properties, including low cellular stiffness in contrast to differentiated cells, which are stiffer. We have previously shown that mESCs lacking the clathrin heavy chain (Cltc), an essential component for clathrin-mediated endocytosis (CME), display a loss of pluripotency and an enhanced expression of differentiation markers. However, it is not known whether physical properties such as cellular stiffness also change upon loss of Cltc, similar to what is seen in differentiated cells, and if so, how these altered properties specifically impact pluripotency. Using atomic force microscopy (AFM), we demonstrate that mESCs lacking Cltc display higher Young''s modulus, indicative of greater cellular stiffness, compared with WT mESCs. The increase in stiffness was accompanied by the presence of actin stress fibers and accumulation of the inactive, phosphorylated, actin-binding protein cofilin. Treatment of Cltc knockdown mESCs with actin polymerization inhibitors resulted in a decrease in the Young''s modulus to values similar to those obtained with WT mESCs. However, a rescue in the expression profile of pluripotency factors was not obtained. Additionally, whereas WT mouse embryonic fibroblasts could be reprogrammed to a state of pluripotency, this was inhibited in the absence of Cltc. This indicates that the presence of active CME is essential for the pluripotency of embryonic stem cells. Additionally, whereas physical properties may serve as a simple readout of the cellular state, they may not always faithfully recapitulate the underlying molecular fate.  相似文献   
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