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81.
OBJECTIVE: Angiotensin (Ang) II increases reactive oxygen species (ROS), decreases nitric oxide (NO) bioavailability and promotes cardiovascular remodeling. ROS have been identified as critical second messengers of the trophic responses by Ang II. In rats with Ang II-induced hypertension, we investigated the role of ROS in cardiac hypertrophy as well as the remodeling of aortas and mesenteric (resistance) arteries. METHODS: Sprague-Dawley rats received Ang II (0.7 mg/kg per day by mini-pump, n = 7) or vehicle (n = 7) for 5 days. Endothelium-dependent relaxation to acetylcholine (EDR) in aortas was determined in organ baths and in mesenteric resistance vessels in a pressurized myograph. Superoxide (O2) production was measured by lucigenin chemiluminescence, laser-confocal fluorescence microscopy (LCM) and NADPH oxidase assay. RESULTS: Ang II-treated rats developed hypertension (183 +/- 3 versus 138 +/- 4 mmHg, P < 0.05), increased aortic O2 (50%), aortic hypertrophy (12%) and impaired EDR. Mesenteric arteries manifested impaired EDR, increased NADPH oxidase activity (356%) and eutrophic inward remodeling (decreased lumen diameter and increased wall/lumen ratio). However, although Ang II-treated rats developed cardiac hypertrophy (13%), this was not accompanied by an increase in cardiac O2, as measured by lucigenin, LCM or NADPH oxidase assay. On the other hand, cardiac calcineurin, a molecule that promotes cardiac hypertrophy linked to Ang II, was increased by 40% (52 +/- 8 versus 33 +/- 5 pmol/min per mg protein, P < 0.05). CONCLUSION: These studies demonstrate that the role of ROS in Ang II-induced vascular remodeling differ across vascular territories. Although in conduit and resistance vessels, vascular hypertrophy and endothelial dysfunction are linked to increased ROS production, cardiac hypertrophy is not. Instead, cardiac hypertrophy is associated, at least in part, with an increase in calcineurin. These studies unveil novel mechanisms that may play an important role in the pathogenesis of cardiac and vascular injury in hypertension. 相似文献
82.
Costi R Violi V Roncoroni L Sarli L 《Hepatology (Baltimore, Md.)》2005,42(3):736; author reply 736-736; author reply 737
83.
Pumar JM Blanco M Vázquez F Castiñeira JA Guimaraens L Garcia-Allut A 《AJNR. American journal of neuroradiology》2005,26(10):2573-2577
We report initial experience with the use of a new intracranial stent, the Leo microstent in combination with detachable coils in treatment of patients with wide-necked cerebral aneurysms. The Leo stent represents a significant advance in the vascular treatment of intracranial aneurysm with high radial force and an easy delivery system. It is a feasible, secure, and effective system. 相似文献
84.
Costi R Himpens J Iusco D Sarli L Violi V Roncoroni L Cadière GB 《Chirurgia italiana》2004,56(3):321-331
Presented as a possible "second" revolution in general surgery after the introduction of laparoscopy during the last few years, the robotic approach to mini-invasive surgery has not yet witnessed wide, large-scale diffusion among general surgeons and is still considered an "experimental approach". In general surgery, the laparoscopic treatment of gastrooesophageal reflux is the second most frequently performed robot-assisted procedure after cholecystectomy. A review of the literature and an analysis of the costs may allow a preliminary evaluation of the pros and cons of robotic fundoplication, which may then be applicable to other general surgery procedures. Eleven articles report 91 cases of robotic fundoplication (75 Nissen, 9 Thal, 7 Toupet). To date, there is no evidence of benefit in terms of duration of surgery, rate of complications and hospital stay. Moreover, robotic fundoplication is more expensive than the traditional laparoscopic approach (the additional cost per procedure due to robotics is 1,882.97 euros). Only further technological upgrades and advances will make the use of robotics competitive in general surgery. The development of multi-functional instruments and of tactile feedback at the console, enlargement of the three-dimensional laparoscopic view and specific "team" training will enable the use of robotic surgery to be extended to increasingly difficult procedures and to non-specialised environments. 相似文献
85.
Romero-Terán O Torres-Contreras LM Mora-Fol JR Andrade-Sepúlveda VR Baeza-Herrera C 《Cirugia y cirujanos》2004,72(3):217-220
Renal artery aneurysm is a rare disease in children and usually is due to fibromuscular dysplasia. Clinical symptoms are frequently high blood pressure, abdominal pain, and hematuria. Diagnosis is carried out by means of angiography. We report the case of a 13-year-old male patient who had renovascular hypertension due to calcification and aneurysm of fibromuscular dysplasia-associated renal artery. We carried out total nephrectomy to resolve high blood pressure. We suggested that presence of discreet calcification in region of renal artery in a boy with renovascular high blood pressure should guide us toward diagnosis of fibromuscular dysplasia-related renal artery aneurysm. 相似文献
86.
CD44 is a polymorphic family of adhesion molecules widely distributed on cells and tissues. CD44 is up-regulated on activated lymphocytes, and it can function as a receptor, mediating rolling and migration. Although it has been demonstrated that anti-CD44 antibodies bound to tissue-culture plates induce multidirectional emission of retractile dendrites ("spreading") in activated murine B lymphocytes, the involvement of cytoskeleton elements in this phenomenon is largely unknown. In this work, it is shown that the generation of dendrites induced by CD44 cross-linking in activated B cells depends on actin, microtubules, and vimentin reorganization. Immunofluorescence analysis showed that dendrite formation began with actin polymerization, and its extension was favored by microtubules and intermediate filaments of vimentin oriented to the polymerized actin. Pretreatment of activated B lymphocytes with cytochalasin E inhibited the dendrites formation; moreover, when cells were treated with this drug at different time points during the dendrite formation process, the stability of the dendrites was affected. In contrast, although the treatment with colchicine and nocodazole (tubulin polymerization inhibitors) inhibited the dendrites formation, it did not inhibit the initial phase of actin polymerization. According to these results, B cell spreading and dendrite formation induced by anti-CD44 antibodies require coordinated rearrangements of actin, microtubules, and vimentin, being the actin cytoskeleton, the most important element that confers stability and drives the morphological changes during B cell spreading, conceivably preparing B lymphocytes for locomotion. 相似文献
87.
Leopoldo M Berardi F Colabufo NA Contino M Lacivita E Niso M Perrone R Tortorella V 《Journal of medicinal chemistry》2004,47(26):6616-6624
A series of N-(1,2,3,4-tetrahydronaphthalen-1-yl)-4-aryl-1-piperazinealkylamides was prepared and their affinity for serotonin (5-hydroxytryptamine, 5-HT) 5-HT7, 5-HT(1A), and 5-HT(2A) receptors was measured by in vitro binding assays. In relation to 5-HT7 receptor affinity, receptor binding studies indicated that (i) the optimal alkyl chain length was five methylenes, (ii) an unsubstituted 1,2,3,4-tetrahydronaphthalenyl nucleus was preferred, and (iii) the substitution pattern of the aryl ring linked to the piperazine ring played a crucial role. Several compound with high affinity for 5-HT7 receptors were identified. Among them, 4-(2-methoxyphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (28), 4-(2-acetylphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (34), 4-(2-methylthiophenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (44), 4-(2-hydroxyphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (46), and 4-(2-methylphenyl)-N-(1,2,3,4-tetrahydronaphthalen-1-yl)-1-piperazinehexanamide (49) were assayed for the 5-HT7 receptor-mediated relaxation of substance P-induced guinea pig ileum contraction. Compounds 28, 44, and 49 behaved as full agonists and compound 34 as a partial agonist, whereas derivative 46 acted as an antagonist. Among the compounds presented here, it emerged that 44 was identified as a potent 5-HT7 receptor agonist (Ki = 0.22 nM, EC50 = 2.56 microM), endowed with selectivity over 5-HT(1A) and 5-HT(2A) receptors (200-fold and >1000-fold, respectively). 相似文献
88.
Bignardi M Antognoni P Sanguineti G Magli A Molteni M Merlotti A Richetti A Tordiglione M Conte L Magno L 《Tumori》2004,90(3):317-323
AIMS AND BACKGROUND: To report results of hyperfractionated radiotherapy for T2N0 glottic carcinoma at a single institution after extended follow-up. METHODS: Between 1980 and 1988 at Varese University Hospital, 60 consecutive patients with T2N0 glottic carcinoma received exclusive radiotherapy consisting of 1.5 Gy/fraction twice a day. Treatment gaps during the radiotherapy course were allowed according to individual tolerance. This policy resulted in a wide range of elapsed treatment time: median, 5.7 weeks; range, 3.7-8.9. Median follow-up is 9.8 years. RESULTS: As a result of dose/time distribution, 16, 20 and 24 patients received an average weekly dose rate of <10 Gy/week, equal to 10 Gy/week or >10 Gy/week, respectively. Mean total dose for each group was 62.8 Gy, 63.7 Gy and 63.8 Gy, respectively. Five-year local-regional control was 69 +/- 6% (95% CI); ultimate local-regional control, including salvage surgery, was 78 +/- 5%. All failures were at the primary site, and no patient developed neck recurrence as first site of failure. The actuarial incidence of grade 2-3 late reactions at 5 years was 42 +/- 6%. Most late toxicity events were grade 2: only 2 patients developed grade 3 reactions and none grade 4. None of the several clinical and treatment-related variables showed any statistically significant impact on local-regional control or late toxicity at univariate and multivariate analysis. In particular, 3-year local-regional control rates were 73 +/- 11%, 84 +/- 8% and 69 +/- 10% for an average weekly dose rate of <10 Gy/week, equal to 10 Gy/week and >10 Gy/week, respectively (not significantly different). CONCLUSIONS: At a very long follow-up, the hyperfractionated regimen tested in the study was shown to be effective and devoid of major complications, provided individual patient acute tolerance is carefully taken into account. Also, time factor did not affect outcome in this series. 相似文献
89.
Enhancing the functioning of parents, teachers, juvenile justice authorities, and other health and mental heal professionals who direct children and adolescents to services is a major mental health services concern. The Gateway Provider Model is an elaborated testable subset of the Network-Episode Model (NEM; B. A. Pescosolido & C. A. Boyer, 1999) that synthesizes it with Decision (D. H. Gustafson, et al., 1999) and organizational theory (C. Glisson, 2002; C. Glisson & L. James, 1992, 2002). The Gateway Provider Model focuses on central influences that affect youth's access to treatment, i.e., the individual who first identifies a problem and sends a youth to treatment (the "gateway provider"); and the need those individuals have for information on youth problems and relevant potential resources. Preliminary studies by the authors and other applicable studies (D. Carise & O. Gurel, 2003) show that providers' perception of need, and their knowledge of resources, and their environment are related to the decision to offer or refer to services, supporting key aspects of the Model. 相似文献
90.
Rueda LM Pecor JE Yuen MC Lee MW 《Journal of the American Mosquito Control Association》2004,20(2):204-207
Mosquito collections were carried out during April 2002 in Hong Kong. Twenty-six species of mosquitoes in 9 genera were collected, including 1 new record, Culex (Culiciomyia) nigropunctatus. Characteristics of larval habitats of these species are described and an updated checklist is included. 相似文献