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Geir Håland Kai-Håkon Carlsen Chandra Sekhar Devulapalli Morten Pettersen Petter Mowinckel Karin C. Lødrup Carlsen 《Pediatric allergy and immunology》2007,18(6):528-534
The aim of the study was to assess if lung function at birth predicts lung function at 2 yr and secondly, if lung function development was influenced by the common phenotypes of recurrent bronchial obstruction (rBO) or atopic eczema (AE) by 2 yr. Lung function was assessed at birth (n = 802) and at 2 yr within the prospective birth cohort study 'the Environment and Childhood Asthma Study' in Oslo. The 135 children with lung function measured at birth by tidal flow volume (TFV) loops and passive respiratory mechanics, who were included in a nested case-control study were reinvestigated at 2 yr with clinical examination, TFV loops (n = 90) (mean age 26.6 (3.7 s.d.) months), skin prick test and parental interview. Children were categorized into quartiles (lower, middle two, upper) according to time to peak tidal expiratory flow/total expiratory time (t(PTEF)/t(E)) at birth as well as clinical phenotype based on the presence of rBO and/or AE (ever) by 2 yr. The observed reduction in mean t(PTEF)/t(E) from birth to 2 yr within the quartiles, were not significantly different after controlling for 'regression to the mean'. t(PTEF)/t(E) at birth correlated significantly with t(PTEF)/t(E) at 2 yr, (r = 0.475, p < 0.001). Children with both rBO and AE by 2 yr had significantly lower t(PTEF)/t(E) at 2 yr (p = 0.002) and at birth (p = 0.027), compared with children with no rBO or AE. Clinical phenotype at 2 yr did not influence the change in t(PTEF)/t(E) from birth to 2 yr. This study demonstrates a clear tracking of lung function from birth, not influenced by rBO or AE by 2 yr. 相似文献
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In Vivo Molecular Imaging Characterizes Pulmonary Gene Expression During Experimental Lung Transplantation 总被引:2,自引:0,他引:2
Sekhar Dharmarajan Makio Hayama James Kozlowski Takaaki Ishiyama Mikio Okazaki Phillip Factor G. Alexander Patterson Daniel P. Schuster 《American journal of transplantation》2005,5(6):1216-1225
Experimental gene therapy is a promising strategy to prevent ischemia-reperfusion (I/R) injury and allograft rejection after lung transplantation, and methods will eventually be needed to characterize pulmonary transgene expression in vivo in humans. Therefore, we studied positron emission tomography (PET) as a means of performing in vivo molecular imaging in rodent models of lung transplantation. Rats were transfected endotracheally with adenovirus encoding a fusion gene of a mutant Herpes simplex virus-1 thymidine kinase and the green fluorescent protein gene (the former serving as an imaging reporter gene). Twenty-four hours after transfection, lungs were transplanted in groups representing normal transplantation, I/R injury and acute allograft rejection. Imaging was obtained either 24 h after transplantation to study reperfusion injury or 4 days after transplantation to study graft rejection. After imaging, lungs were excised and analyzed for thymidine kinase activity. Imaging detected transgene expression in transplanted lungs even in the presence of acute rejection or I/R injury. The PET imaging signal correlated with in vitro lung tissue assays of thymidine kinase activity (r(2) = 0.534). Thus, noninvasive molecular imaging with PET is a feasible, sensitive and quantitative method for characterizing pulmonary transgene expression in experimental lung transplantation. 相似文献
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Protection Against Chemically-Induced Oxidative Gastrointestinal Tissue Injury in Rats by Bismuth Salts 总被引:1,自引:0,他引:1
Debasis Bagchi Owen R. Carryl Minh X. Tran Manashi Bagchi Phillip J. Vuchetich Roger L. Krohn Siddhartha D. Ray Sekhar Mitra Sidney J. Stohs 《Digestive diseases and sciences》1997,42(9):1890-1900
Oxygen free radicals (OFR) are implicated in thepathogenesis of stress, chemically induced gastriclesions, and gastrointestinal injury. Theconcentration-dependent scavenging abilities of bismuthsubsalicylate (SBS), colloidal bismuth subcitrate (CBS), andselected OFR scavengers, including superoxide dismutase(SOD), catalase, mannitol, and allopurinol were examinedagainst biochemically or chemically generated superoxide anion, hydroxyl radical, andhypochlorite radical plus hypochlorous acid based on achemiluminescence assay. Furthermore, both gastric (GM)and intestinal mucosa (IM) were individually exposed in vitro to these free radical generatingsystems, and the concentration-dependent protectiveabilities of SBS and CBS against lipid peroxidation (LP)were compared with selected OFR scavengers. In addition, 24-hr fasted rats were orally treated with thenecrotizing agents 0.6 M HCl, 0.2 M NaOH, 80% ethanol,and aspirin (200 mg/kg). The extent of tissue injury inthe GM and IM was determined by assessing LP, DNA fragmentation, and membrane microviscosity.Dose- and time-dependent in vivo protective abilities ofCBS (100 mg/kg) and SBS (15 mg/kg) were also assessed.Following incubations with superoxide anion and hydroxyl radical generating systems in thepresence of 125 mg SBS/liter, approximately 47% and 61%inhibitions were observed in the chemiluminescenceresponse, respectively, while 48% and 46% inhibitions were observed with 125 mg CBS/liter. SBS andCBS exerted similar abilities towards hypochloriteradical plus hypochlorous acid. Approx. 3.1- and3.7-fold increases in LP were observed in the GM and IMof rats following oral administration of 0.6 MHCl. Pretreatment of the rats with SBS and CBS decreased0.6 M HCl-induced LP in the GM by approx. 39% and 27%,respectively, with similar decreases in LP in the IM. SBS exhibited better protectiveabilities towards 0.6 M HCl and 0.2 m NaOH-induced GMand IM injury as compared to CBS. SBS and CBS providedsimilar protection towards 80% ethanol-induced gastric injury, while CBS exerted a superior protectiveability towards aspirin-induced gastric injury. Theresults demonstrate that both SBS and CBS can scavengereactive oxygen species and prevent tissue damage produced by OFR. 相似文献
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Forty-two patients with neoplasms involving the cavernous sinus had operations between 1983 and 1987. The lesions included 25 benign tumors (e.g., meningioma, neurilemoma) and 17 malignant tumors (e.g., chondrosarcoma, adenoid cystic carcinoma). The cavernous sinus was entered by inferior, anterolateral, or medial extradural approaches or by superior or lateral intradural approaches. The intracavernous internal carotid artery was managed by dissecting tumor away from it or by occlusion and excision with or without direct vein graft reconstruction, based on the results of a preoperative balloon occlusion test. Cranial nerves III, IV, V, and VI usually were dissected from tumor, but in 3 cases of tumor invasion, the excised nerve segment was reconstructed by direct suture or with a sural nerve interposition graft. Twenty-one of the benign tumors and 8 of the malignant tumors were excised totally and the remainder subtotally. On follow-up ranging from 3 to 48 months, one subtotally excised meningioma recurred and was treated with re-excision and adjuvant radiation therapy. Two "totally" excised malignant tumors recurred outside the cavernous sinus at the margins of excision. There was no operative mortality or permanent cerebral morbidity. Postoperatively, the ocular and neurological function of most patients was similar to the preoperative status; in some, it was significantly improved. Thirteen additional patients with intracavernous neoplasms also were evaluated during the same period and followed without operation. The early follow-up information regarding these patients is provided. 相似文献
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An ophthalmic evaluation was undertaken in 250 consecutive cases of mental retardation where no specific etiological diagnosis could be established, ie, "idiopathic" mental retardation. Visual impairment was noted in 59 of these patients, and was mainly due to primary optic atrophy, besides cortical blindness, strabismus, nystagmoid eye movements, refractive errors and various associated congenital ocular anomalies. It was encouraging to find that 191 children had active vision, including 10 patients with definite disc pallor. The importance of useful vision in these retarded children cannot be overemphasized. This is probably the first report in the literature analyzing the ocular changes and their significance in a fairly large series of idiopathic mental retardation. 相似文献
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Objectives To evaluate the efficacy of early arytenoid adduction in the management of vagal paralysis after skull base surgery. Study Design Retrospective evaluation at a tertiary care skull base center. Methods Aggressive surgical management of skull base lesions has become increasingly popular owing to advances in surgical technique and intraoperative monitoring. Temporary and permanent lower cranial neuropathies occur frequently, especially after the surgical management of lesions involving the vertebrobasilar system and the jugular foramen. An injury to the proximal vagus nerve is usually associated with dysphonia and swallowing dysfunction. An early arytenoid adduction has been employed in 26 patients with a vagal paralysis after skull base surgery. Most commonly, the neurosurgical patient underwent an arytenoid adduction under general anesthesia on postoperative day 2. Results Videostroboscopy after arytenoid adduction demonstrated 76% of patients had complete glottic closure. Of those with inadequate glottic closure, all demonstrated a well‐medialized posterior glottis with a persistent anterior glottal gap. These patients were easily treated with a secondary type I thyroplasty under local anesthesia with sedation resulting in complete glottic closure. Despite excellent voice outcomes, 66% of these patients had dysphagia requiring enteral feedings for nutritional support. Conclusions An early arytenoid adduction is an excellent medialization technique that can be performed safely in the early postoperative period under general anesthesia after skull base surgery. 相似文献
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