Postnatal development of cyclooxygenase-2 in the rat kidney

Prostaglandins are local mediators/modulators of kinin effects in the kidney. The prostaglandin G2/H2 synthase (cyclooxygenase, COX) is the key regulatory enzyme of prostanoid synthesis pathway. Two COX isoenzymes (constitutive or COX-1 and inducible or COX-2) have been described in the rat kidney. We have demonstrated the presence of COX-2 in a subset of thick ascending limb of Henle (TAL) cells in normal adult rats [Vio, C.P., Cespedes, C., Gallardo, P., Masferrer, J.L., 1997. Renal identification of cyclooxygenase-2 in a subset of thick ascending limb cells. Hypertension 30, 687-692]. The present work was designed to evaluate COX-2 during the postnatal development of the rat kidney. Kidneys from Sprague-Dawley rats were studied during postnatal days 5, 10, 15 days and adult (60 days) (n = 8 each group). Renal tissue was immunostained with specific antibodies against COX-2. COX-2 was observed exclusively in TAL. A small number of COX-2 cells were observed during early postnatal life, increasing from day 5 to 15, and decreasing thereafter to reach adult levels. During maximal expression, near 20% of TAL were COX-2 positive whereas in early postnatal period and adults, only 2% of TAL cells contain COX-2. This transient induction of COX-2 during development suggest that the enzyme is necessary for the postnatal development of the kidney. This change in COX-2 seems to correspond to a derepression of COX-2 gene expression secondary to low levels of glucocorticoids.     

Complex fractures of the clivus: diagnosis with CT and clinical outcome in 11 patients

During a 20-month period, fractures of the clivus occurring after craniocerebral trauma were diagnosed with computed tomography (CT) in 11 patients. Five patients had longitudinally oriented fractures; these were fatal in four patients due to either vertebral-basilar artery occlusion, brain stem trauma, or both. Six other patients had transversely oriented fractures that extended through the carotid canal and petrous temporal bone. While less frequently contributing directly to mortality, transverse fractures were also associated with cerebrospinal fluid leaks (two patients) and a cavernous sinus-carotid fistula (one patient). They were not as frequently associated with Horner syndrome or cranial nerve deficits as suggested in the current literature. This retrospective evaluation reveals two distinct injury patterns that demonstrate a difference in related morbidity and mortality.     

Distal esophageal ballooning following Heller myotomy

Eccentric ballooning of the distal esophagus was observed radiographically in 11 of 23 patients (48%) who underwent Heller myotomy for achalasia. While, to the authors' knowledge, ballooning at the site of myotomy incision has not been described previously in the radiologic literature, it should be recognized as a normal and frequent postoperative finding. Radiologists should be aware of this finding so that it is not mistaken for postoperative abnormalities following esophagomyotomy or an epiphrenic diverticulum.     

高位腰椎间盘突出症

目的：通过147例高位腰椎间盘突出症的回顾性研究,旨在提高对本症的认识,减少漏诊,误诊,方法：回顾性分析报告147例高位腰椎间盘突出,结果：治疗腰1,210例,腰2。3 32例,腰3,4 105例,其中双间隙突出34例,跳跃性突出27例,伴椎管狭窄31例。瘫痪3例,非手术治疗34例,手术113例,优47例,良8例,差92例,重点讨论了高位腰椎及椎间盘和神经根的解剖特点和临床三大特征及诊断治疗,提出对不同程度的病人用不同治疗方式以及手术中需要注意的六个问题。     

Reversible oxidant-induced increases in albumin transfer across cultured endothelium: alterations in cell shape and calcium homeostasis

To determine whether reactive oxygen molecules could directly and reversibly increase the transfer of albumin across an endothelial barrier, we measured albumin transfer across monolayers of endothelium cultured on micropore filters before and after exposure to xanthine and xanthine oxidase. Xanthine and xanthine oxidase increased endothelial albumin transfer in a dose-dependent fashion. Parallel phase contrast and fluorescence microscopy demonstrated retraction of adjacent cells from one another and disruption of the actin filaments. The oxidant- induced increases in albumin transfer and changes in cell shape were reversed by removing xanthine oxidase and then incubating the monolayers for 3 1/2 hours in tissue culture media enriched with fetal bovine serum. However, incubation in tissue culture media without serum resulted in progressive injury and cell death. Hence, the brief exposure to oxidants initiated a progressive injury process that was reversed by incubation in serum. Because intracellular and extracellular calcium are important determinants of cell shape, and because some oxidized membrane lipids act as calcium ionophores, we asked whether oxidants altered endothelial calcium homeostasis. Xanthine-xanthine oxidase increased release of 45Ca++ from preloaded cells. The calcium antagonist lanthanum chloride prevented xanthine- xanthine oxidase increases in endothelial albumin transfer and prevented the changes in cell shape; chelation of extracellular calcium inhibited lysis of endothelium by xanthine-xanthine oxidase; and the calcium ionophore A23187 increased endothelial albumin transfer and mimicked the oxidant-induced changes in cell shape. Lanthanum chloride inhibited these effects of A23187. These data suggest that oxygen radicals can reversibly increase endothelial permeability to macromolecules, that this is associated with reversible changes in endothelial cell shape and actin filaments, and that the changes in cell shape are related to oxidant-induced changes in endothelial calcium homeostasis.     

蒙药如达溃疡散对大鼠乙酸性胃溃疡及其血清促胃液素的影响

目的:探讨如达溃疡散对大鼠乙酸性胃溃疡的作用及对其血清促胃液素(gastrin)含量的影响.方法:采用乙酸法复制胃溃疡模型,将大鼠随机分为对照组、如达溃疡散组、雷尼替丁组,观察如达溃疡散对大鼠胃溃疡的作用,并检测其对大鼠血清中促胃液素含量的影响.结果:与对照组相比,如达溃疡散能明显抑制溃疡的发生,抑制血清促胃液素含量.结论:如达溃疡散具有抗胃溃疡的作用,其作用机理可能是通过抑制促胃液素释放,进一步减少胃酸分泌来实现的.