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991.

Background:

Renal sympathetic nerves are involved in the reflective activation of the sympathetic nervous system in circulatory control. Catheter-based renal denervation (RDN) ameliorated treatment-resistant hypertension safely, but 10%–20% of treated patients are nonresponders to radiofrequency denervation. The purpose of this study was to investigate the safety and efficiency of cryoablation for sympathetic denervation in a swine model and to explore a new way of RDN.

Methods:

Seven swines randomly assigned to two groups: Renal cryoablation (CR) group and control group. The control group underwent renal angiogram only. The CR group underwent renal angiogram plus bilateral renal cryoablation. Renal angiograms via femoral were performed before denervation, after denervation and prior to the sacrifice to access the diameter of renal arterial and the pressure of aorta abdominalis. Euthanasia of the swine was performed on 28-day to access norepinephrine (NE) changes of the renal cortex and the changes of renal nerves.

Results:

Cryoablation did not induce severe complications at any time point. There was no significant change in diameter of renal artery. CR reduced systolic blood pressure (BP) from 145.50 ± 9.95 mmHg at baseline to 119.00 ± 14.09 mmHg. There was a slight but insignificant decrease in diastolic BP. The main nerve changes at 28-day consisted of necrosis with perineurial fibrosis at the site of CR exposure in conjunction with the nerve vacuolation. Compared with the control group, renal tissue NE of CR group decreased by 89.85%.

Conclusions:

Percutaneous catheter-based cryoablation of the renal artery is safe. CR could effectively reduce NE storing in the renal cortex, and the efficiency could be maintained 28-day at least.  相似文献   
992.
AIM: To provide hepatic protection through administration of doxorubicin before stop-flow chemotherapy (SFC) and to investigate the expression of heat shock protein 72 (HSP72) and role of nuclear factor kappa B (NF-κB) in this effect. METHODS: The hepatic preconditioning of doxorubicin was established in a porcine model by injection of doxorubicin (1 mg/kg) before SFC. The experimental animals were randomized into two groups: groups receiving doxorubicin (DOX) and normal saline (NS). Serial serum and tissue samples were taken from both groups to evaluate the protection of doxorubicin. Western blot and immunoprecipitation were applied to detect the expression of HSP72, NF-κB p65 protein, inhibitor κB-α (IκB-α) and phosphorylated IκB-α as well. The expression of tumor necrosis factor α (TNF-α) was estimated by semiquantitative RT-PCR. And the extent of the hepatic injury was estimated with the level of serum aminotransferases. RESULTS: An abundance production of HSP72 in porcine liver was observed after 24 h of intravenous administration of doxorubicin, but without any change in the expression of NF-κB p65 subunit in cytoplasm. NF-κB p65 subunit accumulated in nuclei at the end of SFC and reached its highest level at 30 min after the restoration of the abdominal circulation and decreased gradually during the 6 h after SFC in NS group, while there was little change in DOX group. There was also a slight decrease of IκB-α at 30 min after the restoration of the abdominal circulation in NS group accompanying with the appearance of phosphorylated IκB-α. The expression of TNF-α was significantly higher in NS group than that in DOX group (average 1.40±0.17 vs 0.62±0.22, P<0.01) at serial time points after SFC. Serum ALT and AST levels of NS group were higher after 24 h than those of DOX group (93.2±7.8 IU/L vs 53.3±13.9 IU/L, 217.0±29.4 IU/L vs 155.0±15.6 IU/L for ALT and AST respectively, P<0.05) and after 48 h than those of DOX group (66.6±18.1 IU/L vs 43.3±16.7 IU/L, 174.4±21.3 IU/L vs 125.7±10.5 IU/L for ALT and AST respectively, P<0.05). CONCLUSION: Doxorubicin renders the liver to be tolerant to the hepatic influence in SFC in a porcine model through the NF-κB/IκB-αpathway with the expression of HSP72.  相似文献   
993.
994.

Purpose

The magnitude of the risk of severe hypoglycemia associated with sulfonylureas as the initial treatment for type 2 diabetes in the real-world setting is unknown. We assessed the risk of severe hypoglycemia associated with initiating monotherapy with sulfonylurea compared with metformin for the treatment of type 2 diabetes.

Methods

By using the UK Clinical Practice Research Datalink and Hospital Episode Statistics linked to the Office for National Statistics, we identified a cohort of patients with type 2 diabetes who initiated sulfonylureas or metformin monotherapy between April 1, 1998, and December 31, 2012, with follow-up until December 31, 2013. Sulfonylurea users were matched one-to-one to metformin users by high-dimensional propensity scores. Hazard ratios (HRs) and 95% confidence intervals (CIs) of severe hypoglycemia, defined as requiring hospitalization, were estimated using Cox proportional hazards models comparing sulfonylureas with metformin monotherapy.

Results

The study cohort consisted of 14,012 initiators of sulfonylureas matched to 14,012 initiators of metformin. The mean treated follow-up time was 1.41 (standard deviation, 1.84) years. Use of sulfonylurea was associated with an elevated incidence of severe hypoglycemia compared with metformin as the initiating monotherapy for type 2 diabetes (incidence rate, 2.4/1000 person-years; 95% CI, 1.90-2.90; HR, 4.53; 95% CI, 2.76-7.45).

Conclusions

Sulfonylureas, when prescribed as the initiating monotherapy for the treatment of type 2 diabetes, is associated with a 4.5-fold increase in the risk of severe hypoglycemia. Given the negative consequences of this outcome, clinicians should consider alternative hypoglycemic agents when metformin is not tolerated or contraindicated.  相似文献   
995.

Background and aims

Dyslipidemia predicts higher risk of coronary events and stroke and might be associated with cerebral small vessel disease (SVD). Previous studies linking blood lipids and SVD have yielded inconsistent results, which may be attributable to sex differences in lipids metabolism. The aim of this study was to investigate the relationships between blood lipids and SVD in neurologically healthy men and women.

Methods and results

Consecutive 817 people aged 50 years or more were enrolled and underwent magnetic resonance imaging scans to evaluate the periventricular white matter lesions (PVWMLs), deep white matter lesions (DWMLs) and silent brain infarction (SBI). Fasting total cholesterol, triglyceride, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol, apolipoprotein A-1 (apoA-1) and apolipoprotein B were assessed. Multivariable logistic regression analyses were performed to determine the associations of blood lipids with PVWMLs, DWMLs and SBI. HDL-C (for PVWMLs: OR 0.36, 95% CI 0.19–0.71; for DWMLs: OR 0.35, 95% CI 0.20–0.63) and apoA-1 (for PVWMLs: OR 0.27, 95% CI 0.11–0.66; for DWMLs: OR 0.22, 95% CI 0.10–0.48) were inversely associated with the severity of PVWMLs and DWMLs in women but not in men after adjustment for age, hypertension, diabetes, current smoking, daily drinking, body mass index and uric acid. Additionally, no blood lipids were significantly associated with SBI.

Conclusions

Our findings demonstrate that sex differences may exist in the associations between lipids and SVD. HDL-C and apoA-1 levels were inversely associated with the severity of PVWMLs and DWMLs in women.  相似文献   
996.
茶多酚治疗慢性酒精性肝损伤的实验研究   总被引:8,自引:0,他引:8  
目的 建立酒精性肝病大鼠模型,观察茶多酚对酒精性肝病大鼠血清氨基转移酶活性和肝脏病理变化的影响,探讨茶多酚对酒精性肝损伤的防治作用。 方法 SD大鼠分成3组:酒精组(酒精7g·kg-1·d-1灌胃)、茶多酚组(酒精7g·kg-1·d-1 茶多酚0.25g·kg-1·d-1灌胃)和对照组(等渗盐水灌胃)。各组分别于4周末、12周末和24周末处死大鼠留取肝脏标本,用于HE染色和Masson染色。 结果 酒精组大鼠血清氧基转移酶水平较对照组升高,茶多酚组大鼠与酒精组相比,其值有明显降低,差异有统计学意义(P<0.05)。HE染色显示酒精组大鼠肝细胞浆出现不同程度的脂肪变性,小叶各带可见不同程度的点、灶状或片状坏死,24周大鼠可见桥接坏死。Masson三色染色可见24周大鼠汇管区边缘有绿染胶原纤维包绕增生,肝窦中可见绿染胶原纤维分布。茶多酚组肝脂肪变和炎症程度轻于酒精组,未发现桥接坏死。 结论 茶多酚对酒精性肝损伤具有一定的保护作用。  相似文献   
997.
998.
INTRODUCTION: The effect of different treatment strategies of atrial fibrillation on left atrial (LA) size has not been compared in lone paroxysmal atrial fibrillation. The objective of the present study was to evaluate the evolution of LA size over time in patients who underwent different treatment interventions. METHODS AND RESULTS: Two hundred forty patients with lone paroxysmal atrial fibrillation were assigned to four groups. The circumferential pulmonary vein ablation (CPVA) group (n = 60) was treated with CPVA, segmental pulmonary vein isolation (SPVI) group (n = 60) with SPVI, AMIO group (n = 60) with amiodarone alone, and AMIO + LO group (n = 60) with amiodarone plus losartan. LA diameter was measured with transthoracic echocardiogram at baseline, 3, 6, 9, and 12 months after the interventions. In the CPVA group, LA size at third, sixth, ninth, and 12th month had a significant decrease than that at baseline and in the other three groups. LA size in patients with atrial fibrillation recurrence in the four groups was significant higher than that in patients with no atrial fibrillation recurrence (P = 0.002-0.001). CONCLUSION: The results suggested that a shortened LA size is not consistent with improved sinus rhythm maintenance. Although maintenance of sinus rhythm is not the only factor in determining shrinking or enlargement of the left atrium, inhibiting or eliminating activity of the pulmonary vein is very important for paroxysmal atrial fibrillation. Atrial fibrillation recurrence is a main factor contributing to enlargement of the LA.  相似文献   
999.
目的探讨伴髓上皮瘤和间叶分化大脑内含有神经毡和菊形团的胚胎性肿瘤的临床病理特点、诊断与鉴别诊断。方法对1例发生在左侧颞顶叶的含有神经毡和菊形团的胚胎性肿瘤伴髓上皮瘤和间叶分化进行组织学、免疫组化观察,并结合文献复习。结果患儿男性,5岁。头颅CT示左侧颞顶叶肿瘤性病变伴钙化,左侧颞骨骨质破坏,考虑左颞顶叶占位。光镜下瘤组织由疏密相间区域构成,致密区域见原始小圆核或短梭形瘤细胞呈片状密集分布,核染色质深,异型性明显,见核分裂象伴多灶性坏死,可见横纹肌样细胞,部分区域见柱状上皮构成的原始神经管样结构或Homer-Wright菊形团形成伴结缔组织增生;稀疏区见分化良好的胶质神经毡样基质内有小型神经元样瘤细胞或节细胞样瘤细胞散在分布。免疫组化:原始神经管样结构基底部vimentin(+),原始瘤细胞和横纹肌样细胞nestin、INI-1和p53(+),横纹肌样细胞NF、Syn、MAP2和Cg A(+),Ki-67为局灶20%,原始神经管样结构CK和EMA(-),横纹肌样细胞SMA(-),横纹肌样细胞GFAP和NSE灶(+),小型神经元样瘤细胞S-100和Neu N(+),Olig2(-/+),β-catenin和desmin(-)。结论大脑内含有多量神经毡和真性菊形团的胚胎性肿瘤伴髓上皮瘤和间叶分化确诊依赖于影像、组织学和免疫组化,需要与髓母细胞瘤、非典型畸胎样/横纹肌样瘤、室管膜母细胞瘤和脉络丛乳头状癌鉴别。  相似文献   
1000.
Objective: To investigate the relation of Fas and Fas ligand (FasL) protein expression with carcinogenesis and metastasis of cardiac carcinoma. Methods: Immunohistochemistry was used to detect Fas and FasL protein expression in 64 cardiac carcinoma tissue samples and 20 normal gastric tissue samples. Relation between FasL and Fas expression, age and gender of gastric cancer patients, and pathological subtype and lymph node metastasis of gastric cancer was analyzed. Results: The Fas expression level was significantly higher in normal gastric tissue samples than in cardiac carcinoma tissue samples (85.0% vs. 25.0%, P<0.001), while the FasL expression level was significantly lower in normal gastric tissue samples than in cardiac carcinoma tissue samples (30.0% vs. 81.3%, P<0.001). The Fas expression level was significantly higher in invasive lymph nodes than in non-invasive lymph nodes (82.9% vs. 56.5%, P<0.003) and in well-differentiated gastric carcinoma tissue samples than in poorly-differentiated cardiac carcinoma tissue samples (50.0% vs. 18.0%, P=0.015). The FasL expression level was significantly lower in well-differentiated cardiac carcinoma tissue samples than in poorly- differentiated cardiac carcinoma tissue samples (42.9% vs. 84.0%, P=0.021). The Fas and FasL expression levels (25.0% and 81.3%) were significantly different in cardiac carcinoma tissue samples (P<0.001), but had a non-linear correlation (P=0.575). Conclusion: Abnormal Fas and FasL expressions in cardiac carcinoma and lymph node tissues are involved in carcinogenesis and metastasis of gastric cancer.  相似文献   
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