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1.
Background and objective: Myocardial infarction (MI) is a common critical disease of the cardiovascular system. The process of MI is often accompanied by the excessive activation of cardiac sympathetic nerves, which leads to arrhythmia. Resiniferatoxin (RTX) is a transient receptor potential vanilloid 1 (TRPV1), involved in the cardiac sympathetic afferent reflex. However, whether RTX can reduce the occurrence of arrhythmia and exert a cardioprotective effect by inhibiting the sympathetic reflex during MI is still unknown. Methods: The left anterior descending artery of cardiac was clamped to construct a model of MI. RTX (50 μg/ml) was used by epicardial application in MI rats. Ventricular electrophysiologic properties were continuously monitored by a body surface ECG. Yrosine hydroxylase (TH) and growth associated protein 43 (GAP43) were detected by Immunofluorescence staining. Connexin43 and transforming growth factor beta receptor 1 (TGF-β1) were detected by western blot. Norepinephrine (NE) and BNP levels in blood and tissue were determined by ELISA. Cardiac function was assessed by echocardiography. Results: The ERP, APD90, QRS, QT and the Tend-Tpeak intervals in MI rats were all prolonged, but decreased after RTX treatment (n = 3, P<0.05). In contrast, the RR interval was shortened in the MI group, but prolonged in the MI+RTX group (n = 3, P<0.05). RTX treatment significantly reduced ventricular arrhythmias after MI. TH- and GAP43-positive nerve densities and TGF-β1, and cx-43 protein expression were up-regulated in the MI group compared to the sham group, and they were decreased in the MI+RTX group compared to the MI group (n = 3, P<0.05). RTX can decrease serum and tissue NE and BNP levels (n = 3, P<0.05). RTX pretreatment significantly decreased heart rate, HW/BW ratio and LVIDS, and increased LVEF andLVFS values (n = 3, P<0.05). Conclusion: RTX improved cardiac dysfunction, ventricular electrophysiologic properties, and sympathetic nerve remodeling in rats with MI by inhibiting the excessive cardiac sympathetic drive.  相似文献   
2.
We propose a high order finite difference linear scheme combined with a high order bound preserving maximum-principle-preserving (MPP) flux limiter to solve the incompressible flow system. For such problem with highly oscillatory structure but not strong shocks, our approach seems to be less dissipative and much less costly than a WENO type scheme, and has high resolution due to a Hermite reconstruction. Spurious numerical oscillations can be controlled by the weak MPP flux limiter. Numerical tests are performed for the Vlasov-Poisson system, the 2D guiding-center model and the incompressible Euler system. The comparison between the linear and WENO type schemes, with and without the MPP flux limiter, will demonstrate the good performance of our proposed approach.  相似文献   
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Stellate ganglion (SG) modification has been investigated for arrhythmia treatment. In this study, transesophageal SG imaging and intervention were explored using a homemade 30F integrated focused ultrasonic catheter in healthy mongrel canines in vivo. Anatomic details of SGs were ultrasonically imaged and evaluated. SG had a heterogeneous echoic structure and characteristic profiles sketched by hyper-echoic outlines in an ultrasonogram. Left SGs in the experimental group were successfully ablated through the esophagus under ultrasonic guidance provided by the catheter itself. Two weeks after the ablation, the QT and QTc of the experimental group decreased compared with those of the sham group and at baseline (both p values < 0.001). Histologic examination revealed that left SGs were destroyed. No major complications were observed. This approach may be further explored as a method for ganglia remodeling evaluation and as a strategy of ganglia modification for arrhythmia and for other diseases.  相似文献   
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Abstract

Background

Comorbidities are commonly seen in patients with coronavirus disease 2019 (COVID-19), but the clinical implication is not yet well-delineated. We aim to characterize the prevalence and clinical implications of comorbidities in patients with COVID-19.  相似文献   
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In order to solve the problem of long-term (>9 months) efficacy in the treatment of Alzheimer''s disease (AD) by conventional therapy (CT), a staged and multiply-targeted sequential therapy based on the evolvement of patterns (STEP) was developed. Its main innovations include: (1) the time order of evolution of patterns defined by Chinese medicine (CM) in AD was found, that is, "the orderly pattern evolution starting from Shen (Kidney) deficiency, progressing to phlegm, stasis and fire, and worsening to severe toxin as well as functional collapse"; (2) the cascade hypothesis of Shen deficiency in AD and its sequential therapy based on Shen-reinforcing was proposed, that is, "reinforcing Shen in the early stage and throughout the whole process, resolving phlegm, activating blood and purging fire in the middle stage, detoxifying and replenishing vitality to stop the collapse in the advanced stage", and through meta-analysis, clinical drug use was optimized, thus the leap from "inferential selection" to "evidence-based selection" was realized; (3) the STEP regimen combined with CT maintained cognitive and behavioral stability in AD patients for at least 12 months, with cognitive enhancement and behavioral synergy after 9 months, and cognitive benefit was superior to CT at 9, 12, 15, 18, 21, and 24 months, respectively. The 2-year cognitive improvement rate was increased by 25.64% (P=0.020) and the cognitive deterioration rate was decreased by 48.71% (P=0.000). Among them, the cognitive and functional benefits of Shen-reinforcing therapy for very early AD (350 cases) for 1 year were better than the placebo (P<0.001), and the dementia conversion rate was reduced by 8.85% (P=0.002). The behavioral symptomatic relief of patients with vascular dementia received fire-purging therapy (540 cases) was superior to those received CT (P=0.016). These data suggested that the STEP regimen has synergistic effects on CTs at least in terms of cognitive benefit, and the earlier the use, the greater the benefit will have. Therefore, the STEP regimen should be considered as one of the clinical options, particularly for the dearth of effective pharmaceutical or immunological interventions that are currently available for AD.  相似文献   
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ABSTRACT

Objectives: Limited evidence has suggested that cefoperazone-sulbactam causes coagulation disorders and bleeding.

Methods: The authors conducted a retrospective study to compare patients receiving cefoperazone-sulbactam versus those treated with cefoperazone-tazobactam or ceftazidime. Propensity-score matching was used to explore whether treatment with cefoperazone-sulbactam increased the risk of prothrombin time (PT) prolongation, coagulation disorders, and bleeding, or decreased platelets (PLT).

Results: The cohort included 23,242 patients. Among patients receiving cefoperazone-sulbactam, the risk of PT prolongation, coagulation disorders, decreased PLT, and bleeding was 5.3%, 9.2%, 15.7%, and 4.2%, respectively. Propensity-score matching analyses suggested that cefoperazone-sulbactam increased the risk of PT prolongation (aOR 2.26, 95% CI 1.61–3.18), coagulation disorders (aOR 1.81, 95% CI 1.43–2.30), and decreased PLT (aOR 1.46, 95% CI 1.25–1.72), but not increase bleeding (aOR 1.05, 95% CI 0.79–1.40) compared with ceftazidime. Patients receiving cefoperazone-sulbactam had higher risk of PT prolongation (aOR 1.53, 95% CI 1.11–2.10), coagulation disorders (aOR 1.53, 95% CI 1.21–1.95), but not decreased PLT (aOR 0.93, 95% CI 0.81–1.07) or bleeding (aOR 1.11, 95% CI 0.87–1.42), compared with those receiving cefoperazone-tazobactam.

Conclusion: Cefoperazone-sulbactam may be associated with a higher risk of PT prolongation and coagulation disorders compared with cefoperazone-tazobactam and ceftazidime.  相似文献   
10.
Pancreatic cancer is a lethal disease characterized by early metastasis, local invasion, and resistance to conventional therapies. To understand its etiology and eventually make prevention of it possible and effective, appropriate carcinogenesis models will certainly help us understand the effects of environmental and genetic elements on pancreatic carcinogenesis. The development of new treatment strategies to control cancer metastasis is of immediate urgency. Fulfillment of this task relies on our knowledge of the cellular and molecular biology of pancreatic cancer metastasis and the availability of biologically and clinically relevant model systems. Many of the existing pancreatic cancer carcinogenesis and metastasis animal models are described in this review. The advantages and disadvantages of each model and their clinical implications are discussed, and special attention is focused on experimental therapeutic strategies targeting pancreatic cancer metastasis.  相似文献   
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