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51.
目的 探讨双歧杆菌对坏死性小肠结肠炎(necrotizing enterocolitis,NEC)新生大鼠模型肠道通透性及血清Zonulin表达的影响,分析双歧杆菌保护NEC可能的机制.方法 将60只新生1d的SD大鼠按随机数字表法分为3组(n=20):对照组、坏死性小肠结肠炎新生大鼠组(NEC组)及双歧杆菌干预坏死性小肠结肠炎新生大鼠组(NEC+ BIF组).3组于第1、2、3天固定时间点测量体质量;第4天处死大鼠,HE染色观察回盲部肠组织病理学变化并行病理学评分,异硫氰酸荧光素-葡聚糖(FITC-Dextran)示踪法检测肠黏膜通透性,ELISA检测血清Zonulin的水平,Western blot及免疫组化检测肠组织紧密连接蛋白的表达及分布,将3组大鼠血清Zonulin水平与肠道通透性及紧密连接蛋白表达量行相关性分析.结果 与NEC组相比,双歧杆菌干预后大鼠肠上皮损伤明显改善;而与对照组相比,NEC组肠道通透性显著增高(P<0.05),血清Zonulin表达明显增加(P<0.05),肠上皮紧密连接蛋白Claudin-1、Occludin、ZO-1的表达明显减少(P<0.05),且分布不连续;与NEC组相比,NEC+BIF组肠道通透性降低(P<0.05),血清Zonulin表达降低(P<0.05),肠上皮紧密连接蛋白的表达增加(P<0.05).相关性分析显示,3组大鼠血清Zonulin水平与肠道通透性呈正相关(r=0.923,P<0.01),而血清Zonulin水平与肠组织紧密连接Claudin-1、Occludin、ZO-1蛋白表达量均呈负相关(r=-0.779,P<0.01;r=-0.920,P<0.01;r=-0.619,P<0.01).结论 双歧杆菌可明显改善NEC大鼠的肠道通透性,其机制可能与抑制Zonulin的表达有关.  相似文献   
52.
This study set out to determine whether the fat pad at the attachment of the Achilles tendon has features enabling it to function as an immune organ and a mechanosensory device, and to be a source of pain in insertional tendon injuries. Sections for histology and immunohistochemistry were cut from the Achilles tendon enthesis organ of 1 day old, 1 month, 4 month and 24 month old rats. For fluorescence and peroxidase immunohistochemistry, cryosections were labelled with primary antibodies directed against PGP9.5, substance P, neurofilament 200, calcitonin gene related peptide, CD68, CD36, myeloid related protein 14, actin and vinculin. The fat pad contained not only adipocytes, but also fibrous tissue, mast cells, macrophages, fibroblasts and occasional fibrocartilage cells. It was richly innervated with nerve fibres, some of which were likely to be nociceptive, and others mechanoreceptive (myelinated fibres, immunoreactive for neurofilament 200). The fibres lay between individual fat cells and in association with blood vessels. In marked contrast, the enthesis itself and all other components of the enthesis organ were aneural at all ages. The presence of putative mechanoreceptive and nociceptive nerve endings between individual fat cells supports the hypothesis that the fat pad has a proprioceptive role monitoring changes in the insertional angle of the Achilles tendon and that it may be a source of pain in tendon injuries. The abundance of macrophages suggests that the adipose tissue could have a role in combating infection and/or removing debris from the retrocalcaneal bursa.  相似文献   
53.
54.
目的探讨山姜素对葡聚糖硫酸钠诱导的溃疡性结肠炎小鼠的保护作用及其作用机制。方法 C57BL/6小鼠随机分为对照组、模型组和25、50、100 mg/kg山姜素组。模型组和治疗组每天给予3%葡聚糖硫酸钠溶液,连续7 d。治疗组每日ip生理盐水0.5 m L+25、50、100 mg/kg山姜素,对照组和模型组每天ip生理盐水0.5 m L,连续7 d。观察小鼠体质量变化、结肠长度、疾病活动指数(DAI)评分、组织学损伤评分等炎症反应;透射电镜观察肠上皮细胞间连接;免疫组织化学法、Western blotting法检测肠道紧密连接蛋白claudin-2、occludin、ZO-1、STAT3、p STAT3、IL-6的表达和STAT3/IL-6信号通路的表达情况。结果与模型组比较,山姜素能够显著缓解小鼠体质量减轻和肠管缩短,降低DAI和组织学评分。山姜素可增强小鼠肠黏膜occludin、ZO-1表达,减弱claudin-2表达,并能够抑制STAT3/IL-6信号通路。结论山姜素能够上调葡聚糖硫酸钠诱导的溃疡性结肠炎小鼠结肠组织occludin、ZO-1的表达,下调claudin-2的表达,通过调节紧密连接蛋白的表达,保护肠上皮细胞屏障的完整性和通透性。通过抑制IL-6/STAT3通路,减轻结肠炎症反应。  相似文献   
55.
《Foot and Ankle Surgery》2022,28(8):1314-1320
Orthoses are an important part of both conservative and operative treatment of acute Achilles tendon rupture as they can be used to position the foot in equinus and protect the torn tendon from strain in the healing phase. The aim of the study was to test four different orthoses ability to position the foot in equinus. The study was performed as a cross-sectional study. 15 healthy study participants underwent radiographic examination with 11 true lateral radiographs of the right ankle and foot, one with the ankle joint in neutral position; one of a circular equinus cast (CEC); three of an adjustable equinus boot (AEB) with the foot in 30°, 15°, and 0° of plantar flexion, respectively; three of a fixed angle orthosis with 1, 2, and 3 wedges with a plateau (WWP); and three of a fixed angle orthosis with 1, 2, and 3 wedges without plateau (WWOP). The primary outcome was the Achilles Relief Distance (ARD). Secondary outcomes were the tibiocalcaneal angle (TCA), the tibiotalar angle (TTA), and the tibio- 1st metatarsal angle (1MTP). All measurements were performed by a radiologist. The mean (SD) ARD was 11 mm (7) in CEC, 23 mm (6) with 3 WWP, 11 mm (5) with 3 WWOP, and 15 mm (5) using AEB in 30° of plantarflexion. The mean (SD) TCA was 86° (7,8) in CEC, 76° (7,3) with 3 WWP, 90° (6,9) with 3 WWOP, and 84° (6,6) using the AEB in 30° of plantarflexion. CEC, AEB, and WWOP showed statistically significantly larger plantarflexion than WWP. CEC, AEB and WWOP produced significantly greater plantarflexion compared to WWP.  相似文献   
56.
《Surgery (Oxford)》2020,38(2):100-107
The complexity of foot and ankle anatomy and biomechanics gives imaging an essential role in the diagnosis and management of foot and ankle pathology. This article will focus on the common non-traumatic and non-neoplastic conditions routinely encountered in orthopaedics and musculoskeletal radiology practice.  相似文献   
57.
Ossification of the Achilles tendon is a relatively common finding. However, a large ossification covering more than two third of the tendon is rarely seen. A 70 year old patient with a 12 cm long Achilles tendon ossification is discussed. The ossification was surgically removed and the tendon was subsequently reconstructed using a fascia lata autograft. Postoperatively the ankle was immobilised for 3 months. One year postoperatively the patient was completely recovered with the ability to stand on his toes, and minimal loss in range of motion.Level of clinical evidence4  相似文献   
58.
Cisplatin (CP) is an antineoplastic agent that induces nephrotoxicity and oxidative stress. It is unknown whether renal tight junction (TJ) proteins expression and localization are modified in CP-induced nephrotoxicity.

Objective: To study if the expression of the TJ proteins occludin, claudin-2, claudin-5 and zonula occludens-1 (ZO-1) is modified in rats with CP-induced nephrotoxicity.

Materials and methods: Male Wistar rats (n?=?5/group) were injected with saline solution (V group), and the other group (CP group) was injected with a single dose of saline solution and CP (7.5?mg/kg i.p.). Rats were sacrificed 72?h after CP injection and blood, and 24-h urine samples were collected. Several plasma and urinary injury biomarkers as well as renal histopathology lesions, oxidative and nitrosative stress markers were evaluated, and protein levels of ocludin, claudin-2, claudin-5, ZO-1 were measured by Western blot. Statistically significant changes noted with different p?Results: Nephrotoxicity was evident by histological alterations, glycosuria, decrease in creatinine clearance, increase in fractional excretion of sodium, serum creatinine and kidney injury molecule-1. These changes were associated with oxidative/nitrosative stress (increased renal abundance of 3-nitrotyrosine and protein kinase Cβ2 and decreased renal expression of nuclear factor-erythroid-2-related factor 2) and decreased activity of antioxidant enzymes. Finally, it was found that CP-induced renal damage was associated with decreased renal expression of occludin and claudin-2.

Discussion and conclusion: CP altered the TJ proteins expression and localization in the proximal tubule that was associated with oxidative/nitrosative stress.  相似文献   
59.
60.
The percutaneous technique of Achilles tendon repair seems to offer satisfactory clinical and functional results, although these results have been evaluated mainly using objective rating scales. Recently, some “subjective” rating scales have been combined to evaluate the results of various surgical treatments. The purpose of the present study was to compare the results of a percutaneous Achilles tendon repair evaluated objectively using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score and subjectively using the Medical Outcomes Study, short-form, 36-item questionnaire (SF-36) questionnaire. A total of 17 consecutive patients were treated for acute Achilles tendon rupture using the modified percutaneous Ma and Griffith technique. We reviewed all patients with a follow-up of 24 to 64 months (mean 45.5). At the final follow-up visit, the AOFAS ankle-hindfoot score of each patient was compared with each 1 of the 8 domains of the SF-36 questionnaire, using the parametric Pearson correlation coefficient and the equivalent nonparametric Spearman rho correlation coefficient. The relation between the objective (AOFAS) and subjective (SF-36) results showed a significant correlation (Pearson's correlation coefficient) between the physical functioning (r = 0.597, p = .011) and bodily pain (r = 0.663, p = .004) SF-36 domains, and a nonstatistically significant correlation with the other SF-36 domains. Very similar results were found using the nonparametric Spearman rho correlation coefficient. These results suggest that regarding pain and function, the AOFAS ankle-hindfoot score and SF-36 provide complementary information; therefore, we believe that the SF-36 questionnaire should be used with the AOFAS ankle-hindfoot score for a more complete evaluation of the outcome.  相似文献   
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