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41.
42.
目的:观察氯化钆(GdCl3)诱导急性坏死性胰腺炎(ANP)肺泡巨噬细胞(AM)凋亡时核因子-κB(NF-κB)表达情况,探讨NF-κB在其中的作用及机制。
方法:36只SD大鼠随机分为正常对照组,ANP组,GdCl3治疗组。逆行性胰胆管注射5%牛磺胆酸钠建立ANP大鼠模型,正常对照组大鼠以同法注入生理盐水,GdCl3治疗组制模后即刻自阴茎背静脉注射GdCl3。各组大鼠于成模后6 h经支气管肺泡灌洗获取AM,检测支气管肺泡灌洗液(BALF)中TNF-α和IL-1β含量及肺组织髓过氧化物酶(MPO)水平。用琼脂糖凝胶电泳、流式细胞仪检测AM的凋亡情况;Western-blot检测AM中NF-κB活性。同时对肺组织行病理学检查。
结果:ANP组TNF-α和IL-1β含量高于对照组(P<0.05),而治疗组显著低于ANP组(P<0.05)。仅治疗组DNA电泳见典型的细胞凋亡的梯状条带。对照组,ANP组,治疗组AM凋亡率分别为(10.81±0.86)%,(6.47±1.52)%,(17.41±3.36)%,3组间差异均有统计学意义(P<0.05);Western-blot检测3组AM中NF-κB表达的相对灰度值分别为(0.80±0.05),(1.96±0.15),(1.42±0.10),3组间差异亦有统计学意义(P<0.05)。AM的凋亡率与NF-κB活性呈负相关(r=-0.554,P<0.01)。
结论:GdCl3可能通过抑制NF-κB的活化诱导大鼠ANP肺泡巨噬细胞凋亡,从而减轻肺损伤。  相似文献   
43.
A 61-year-old female with refractory corrosive esophageal stenosis repeatedly underwent endoscopic balloon dilation at another hospital; however, no improvements were observed in the esophageal stenosis. Consequently, she had been on a liquid diet for the previous three years. She was admitted to our department for further treatment. A radial incision was made, by use of the SB knife Jr, for a pinhole-like stenosis in a short segment 39 cm from the incisor, and dilation was safely performed by use of a CRE balloon dilator. Subsequently, prednisolone was orally administered to prevent re-stenosis. This was followed by a favorable clinical course.  相似文献   
44.
Blood flow directions of the portal trunk, splenic vein, and superior mesenteric vein were studied using an ultrasonic Doppler duplex system in 146 healthy adults, 132 patients with liver cirrhosis, 76 with hepatocellular carcinoma, 32 with idiopathic portal hypertension, 134 with chronic hepatitis, 18 with acute hepatitis, and 142 with other diseases. Spontaneous hepatofugal flow in one or more of the three vessels examined was detected in 14 patients. Spontaneous hepatofugal flow in the portal trunk was detected in three patients with liver cirrhosis. In two of these three patients, the hepatofugal flow in the portal trunk disappeared after medication. This is interesting, since hepatofugal flow may, in fact, be more common than we suspected in patients who, because of the severity of their disease, are not able to undergo invasive examination. Postoperative hepatofugal flow in the portal system was detected in 20 of 71 cases: 15/17 patients after interposition mesocaval shunting, 2/17 after distal splenorenal shunting, 2/31 after splenectomy, and 1/6 after splenic artery occlusion with steel coils. In more than half the cases of interposition mesocaval shunting (9/17 patients), blood flow in the portal trunk was hepatofugal. However, hepatopetal blood flow in the portal trunk was maintained in most cases of distal splenorenal shunting (13/17), showing the merits of this technique as a selective portosystemic shunt operation.  相似文献   
45.
Gene expression for growth hormone (GH)/prolactin (PRL)/somatolactin (SL) family hormones in the pituitaries of homing chum salmon were examined, because gene expression for these hormones during ocean-migrating phases remains unclear. Fish were collected in the winter Gulf of Alaska, the summer Bering Sea and along homing pathway in the Ishikari River-Ishikari Bay water system in Hokkaido, Japan in autumn. The oceanic fish included maturing adults, which had developing gonads and left the Bering Sea for the natal river by the end of summer. The absolute amounts of GH, PRL and SL mRNAs in the pituitaries of the maturing adults in the summer Bering Sea were 5- to 20-fold those in the winter Gulf of Alaska. The amount of GH mRNA in the homing adults at the coastal seawater (SW) areas was smaller than that in the Bering fish, while the amount of PRL mRNA remained at the higher level until fish arrived at the Ishikari River. The gill Na+,K+-ATPase activity in the coastal SW fish and the plasma Na+ levels in the brackish water fish at the estuary were lowered to the levels that were comparable to those in the fresh water (FW) fish. In conclusion, gene expression for GH, PRL and SL was elevated in the pituitaries of chum salmon before initiation of homing behavior from the summer Bering Sea. Gene expression for GH is thereafter lowered coincidently with malfunction of SW adaptability in the breeding season, while gene expression for PRL is maintained high until forthcoming FW adaptation.  相似文献   
46.
Objective The change in serum lipid levels by direct-acting antiviral (DAA) treatment for chronic hepatitis C varies depending on the type of DAA. How the lipid level changes induced by glecaprevir-pibrentasvir (G/P) treatment contribute to the clinical outcome remains unclear. We conducted a prospective observational study to evaluate the effectiveness of G/P treatment and the lipid level changes. Methods The primary endpoint was a sustained virologic response at 12 weeks (SVR12). The total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglyceride (TG) levels and LDL-C/HDL-C (L/H) ratio were measured every two weeks. Patients This study included 101 patients. Seventeen cases of liver cirrhosis and nine cases of DAA retreatment were registered. The G/P treatment period was 8 weeks in 74 cases and 12 weeks in 27 cases. Results SVR12 was evaluated in 96 patients. The rate of achievement of SVR12 in the evaluable cases was 100%. We found significantly elevated TC and LDL-C levels over the observation period compared to baseline. The serum levels of HDL-C did not change during treatment but were significantly increased after treatment compared to baseline. The L/H ratio was significantly increased two weeks after the start of treatment but returned to the baseline after treatment. Conclusion The primary endpoint of the SVR12 achievement rate was 100%. G/P treatment changed the serum lipid levels. Specifically, the TC and LDL-C levels increased during and after treatment, and the HDL-C levels increased after treatment. G/P treatment may be associated with a reduced thrombotic risk. Therefore, validation in large trials is recommended.  相似文献   
47.
Immunoglobulin G (IgG) antibodies to Epstein-Barr virus (EBV) nuclear antigens 2 and 1 (EBNA-2 and EBNA-1, respectively) were studied using sera from healthy individuals of a population with a high incidence of asymptomatic primary EBV infections during infancy or childhood in Japan. Two CHO-K1 cell lines expressing EBNA-2 and EBNA-1 were used for anticomplement and indirect immunofluorescence assays. The positivity rate for EBNA-2 IgG rose in the 1- to 2-year age group, increased and remained at a plateau ( approximately 45%) between 3 and 29 years of age (3- to 4-, 5- to 9-, 10- to 14-, and 15- to 29-year age groups), and then reached 98% by age 40 (>/== 40-year age group). Both seropositivity for EBNA-1 and seropositivity for EBNAs in Raji cells (EBNA/Raji) were detected in the 1- to 2-year age group, remained high, and finally reached 100% by age 40. The geometric mean titer (GMT) of EBNA-2 IgG reached a plateau in the 5- to 9- and 10- to 14-year-old groups and remained elevated in the older age groups (15 to 29 and >/== 40 years). The GMT of EBNA-1 IgGs increased to a plateau in the 1- to 2-year-old group and remained unchanged in the older age groups. The GMT of EBNA/Raji IgGs also reached a plateau in the 1- to 2-year-old group, remained level throughout the 3- to 14-year age groups, and decreased in the 15- to 29-year-olds. EBNA-2 IgGs emerged earlier than EBNA-1 IgGs in 8 of 10 patients with infectious mononucleosis, who were between 1 and 27 years old, and declined with time in three of eight cases. These results suggest that EBNA-2 IgG antibodies evoked in young children by asymptomatic primary EBV infections remain elevated throughout life, probably because of reactivation of latent and/or exogenous EBV superinfection.  相似文献   
48.

Aims of the study

Meconopsis quintuplinervia, a medicinal herb endemic to the Tibetan region, is used to treat hepatitis. The aim of this study is to evaluate the antioxidant potential of the ethanolic extract of this herb using different assays.

Materials and methods

The antioxidant capacity of Meconopsis quintuplinervia was investigated using various established in vitro systems. An in vivo study of carbon tetrachloride (CCl4)-induced antioxidant activity in mice was also conducted by examining the levels of malondialdehyde (MDA) and the activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH).

Results

The extract showed strong in vitro antioxidant ability. In the in vivo study, CCl4-induced oxidative stress caused significant decreases in the SOD, CAT, and GSH levels and a significant increase in the MDA level, most of which were significantly reversed (except for SOD in the liver.) by treatment with the extract and standard Vitamin E.

Conclusion

This study clearly indicates that the ethanolic extract of Meconopsis quintuplinervia is a valuable source of natural antioxidants. These findings provide scientific support for the traditional use of this herb as a Tibetan medicine for liver diseases.  相似文献   
49.
We previously reported that angiotensin II type 1 receptor (AT1R) blockade attenuates renal inflammation/fibrogenesis in immune-mediated glomerulonephritis via angiotensin II type 2 receptor (AT2R). In the present study, further in vivo experiments revealed that AT2R was expressed in tubular epithelial cells of nephritic kidneys in mice, and feedback activation of the renin-angiotensin system during AT1R blockade significantly reduced p-ERK, but not intranuclear nuclear factor-kappaB, levels via AT2R. This led to reduction in mRNA levels of the proinflammatory mediator monocyte chemoattractant protein-1 and overall interstitial inflammation and subsequent fibrogenesis. Specific blockade of ERK expression in tubular epithelium by anti-sense oligodeoxynucleotides also attenuated interstitial inflammation, mimicking the anti-inflammatory action of AT2R in nephritic kidneys. Alternatively, we succeeded in confirming such an AT(2)R function by demonstrating that AT1R blockade did not confer renoprotection in nephritic, AT2R gene-deficient mice. Additional in vitro experiments revealed that AT2R activation did not affect nuclear factor-kappaB activation by tumor necrosis factor-alpha in cultured tubular epithelial cells, although it inhibited ERK phosphorylation, which reduced monocyte chemoattractant protein-1 mRNA levels. These results suggest that feedback activation of AT2Rs in tubular epithelium of nephritic kidneys plays an important role in attenuating interstitial inflammation.  相似文献   
50.
血浆TPO水平变化与血小板减少疾病的关系   总被引:2,自引:0,他引:2  
目的:探讨血浆血小板生成素(Thrombopoietin,TPO)水平变化与血小板减少疾病的关系。方法:采用多抗夹心酶联免疫吸附法对68例各种不同原因致血小板减少患者通过应用白介素-11(rhIL-11)来动态检测TPO水平,rhIL-11剂量为25μg/(kg.d),皮下注射,连用10天。结果:(1)急性白血病(Acute leukemia,AL)化疗后血小板减少患者TPO水平低于正常对照组;再生障碍性贫血(Aplastic anemia,AA)及骨髓增生异常综合征(Myelodysplastic syndrome,MDS)患者TPO水平高于正常对照组;原发性血小板减少性紫癜(Idiopathic thrombocytopenic purpura,ITP)及肝硬化(Liver cirrhosis)患者TPO水平与正常对照组无明显差异。而其中的白血病化疗后血小板减少患者和AA患者的骨髓巨核细胞数较TPO正常组显著降低。(2)上述疾病患者用rhIL-11有效者TPO水平趋于正常,无效或疗效欠佳者,则TPO无变化。有效者TPO水平与血小板计数呈负相关。结论:血浆TPO检测,有助于临床鉴别各种血小板减少疾病的病因,对血小板减少患者合理应用rhIL-11提供理论的依据。  相似文献   
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