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91.
OBJECTIVE: To collect information on clinical practice and current management strategies in 22 Italian neurosurgical hospitals for patients with aneurysmal subarachnoid hemorrhage. DESIGN AND SETTING: Observational 6-month study for prospective data collection. PATIENTS: 350 cases of aneurysmal subarachnoid hemorrhage. MEASUREMENTS AND RESULTS: Each center enrolled from 4-36 patients. Neurological deterioration (24%) was more frequent in patients with higher Fisher classification, and with pretreatment rebleeding and it was associated with an unfavorable outcome (46%, 36/78, vs. 33%, 83/251). Aneurysms were mainly secured by clipping (55%, 191/350). An endovascular approach was utilized in 35% (121/350). The more frequent medical complications were fever, recorded in one-half of cases, pneumonia (18%), sodium disturbances (hyponatremia 22%, hypernatremia 17%), cardiopulmonary events as neurogenic pulmonary edema (4%) and myocardial ischemia (5%). Intracranial hypertension was experienced in one-third of the patients, followed by hydrocephalus (29%) and vasospasm (30%). Cerebral ischemia was found in an about one-quarter of the cohort. To identify the independent predictors of outcome we developed a model in which the dichotomized Glasgow Outcome Scale was tested as function of extracranial and intracranial complications. Only high intracranial pressure and deterioration in neurological status were independent factors related to unfavorable outcome. CONCLUSIONS: Our data confirm that in every step of care there is extreme heterogeneity among centers. These patients are complex, with comorbidities, immediate risk of rebleeding, and delayed risk of intracranial and medical complications. Following SAH early treatment and careful intensive care management requires the careful coordination of the various clinical specialties. 相似文献
92.
93.
Neurotrophins promote revascularization by local recruitment of TrkB+ endothelial cells and systemic mobilization of hematopoietic progenitors 总被引:1,自引:0,他引:1
Kermani P Rafii D Jin DK Whitlock P Schaffer W Chiang A Vincent L Friedrich M Shido K Hackett NR Crystal RG Rafii S Hempstead BL 《The Journal of clinical investigation》2005,115(3):653-663
The neurotrophin brain-derived neurotrophic factor (BDNF) is required for the maintenance of cardiac vessel wall stability during embryonic development through direct angiogenic actions on endothelial cells expressing the tropomysin receptor kinase B (TrkB). However, the role of BDNF and a related neurotrophin ligand, neurotrophin-4 (NT-4), in the regulation of revascularization of the adult tissues is unknown. To study the potential angiogenic capacity of BDNF in mediating the neovascularization of ischemic and non-ischemic adult mouse tissues, we utilized a hindlimb ischemia and a subcutaneous Matrigel model. Recruitment of endothelial cells and promotion of channel formation within the Matrigel plug by BDNF and NT-4 was comparable to that induced by VEGF-A. The introduction of BDNF into non-ischemic ears or ischemic limbs induced neoangiogenesis, with a 2-fold increase in the capillary density. Remarkably, treatment with BDNF progressively increased blood flow in the ischemic limb over 21 days, similar to treatment with VEGF-A. The mechanism by which BDNF enhances capillary formation is mediated in part through local activation of the TrkB receptor and also by recruitment of Sca-1+CD11b+ pro-angiogenic hematopoietic cells. BDNF induces a potent direct chemokinetic action on subsets of marrow-derived Sca-1+ hematopoietic cells co-expressing TrkB. These studies suggest that local regional delivery of BDNF may provide a novel mechanism for inducing neoangiogenesis through both direct actions on local TrkB-expressing endothelial cells in skeletal muscle and recruitment of specific subsets of TrkB+ bone marrow-derived hematopoietic cells to provide peri-endothelial support for the newly formed vessels. 相似文献
94.
Chemotherapy- or radiation-induced myelosuppression results in apoptosis of cycling hematopoietic cells and induces regression of bone marrow (BM) sinusoidal vessels. Moreover, timely regeneration of BM neovessels is essential for reconstitution of hematopoiesis. However, the identity of angiogenic factors that support reconstitution of BM's vasculature is unknown. Here, we demonstrate that angiopoietin/tyrosine kinase with immunoglobulin and epidermal growth factor homology domains-2 (Tie2) signaling contributes to the assembly and remodeling of BM neovessels after myelosuppression. Using transgenic mice where the Tie2 promoter drives the reporter LacZ gene (Tie2-LacZ), we demonstrate that at steady state, there was minimal expression of Tie2 in the BM vasculature. However, after 5-fluorouracil (5-FU) treatment, there was a rapid increase in plasma vascular endothelial growth factor A (VEGF-A) levels and expansion of Tie2-positive neovessels. Inhibition of Tie2 resulted in impaired neoangiogenesis, leading to a delay in hematopoietic recovery. Conversely, angiopoietin-1 (Ang-1) stimulated hematopoiesis both in wild-type and thrombopoietin-deficient mice. In addition, Ang-1 shortened the duration of chemotherapy-induced neutropenia in wild-type mice. Exogenous VEGF-A and Ang-1 stimulated Tie2 expression in the BM vasculature. These data suggest that VEGF-A-induced up-regulation of Tie2 expression on the regenerating vasculature after BM suppression supports the assembly of sinusoidal endothelial cells, thereby promoting reconstitution of hematopoiesis. Angiopoietins may be clinically useful to accelerate hemangiogenic recovery after myelosuppression. 相似文献
95.
Farshad Arsalandeh Fariba Khodagholi Shahin Ahmadian Forough Foolad Hamed Mohammadi Kamsorkh Mahdi Moridi Farimani 《Nutritional neuroscience》2019,22(4):295-301
Growing evidence sheds light on the use of flavonoids as the promising alternatives for the treatment of chronic conditions, including cancer and neurodegenerative disorders. Accordingly, in the present study, we aimed at evaluating the effects of oral intake of two structurally different flavonoids 5-hydroxy-6,7,4?-trimethoxyflavone (flavone 1) and 5,7,4?-trihydroxyflavone (flavone 2) on recognition memory, hippocampal protein level of immediate early gene cFos and mitochondrial dynamic markers in Amyloid β (Aβ)-injected rats. Recognition aspect of memory and level of proteins were measured using novel object recognition test and Western blot, respectively. Our data indicated that even though flavone 1 was more effective than flavone 2 to prevent memory impairment, feeding with both flavones alleviated memory in Aβ-injected rats. Furthermore, in flavones-administered rats, mitochondrial dynamic balancing returned to the control level by the decline in Dynamin-related protein-1 protein level, a known marker for mitochondrial fission, and elevation in protein level of mitochondrial fusion factors Mitofusins 1 and 2. In parallel with behavior results, flavone 1 was more effectual on mitochondrial dynamic moderating. The more neuroprotective effects of flavone 1 could be attributed to its methylated structure leading to crossing of the blood-brain barrier with ease and metabolic stability and bioactivity. 相似文献
96.
Liver Histology Changes in Nonalcoholic Steatohepatitis after One Year of Treatment with Probucol 总被引:3,自引:0,他引:3
Merat S Aduli M Kazemi R Sotoudeh M Sedighi N Sohrabi M Malekzadeh R 《Digestive diseases and sciences》2008,53(8):2246-2250
BACKGROUND: Probucol, a lipid-lowering agent with antioxidant effects, is effective in normalizing liver enzymes in patients with nonalcoholic steatohepatitis (NASH). We studied changes in the liver histology of patients with NASH after use of probucol for one year. METHODS: Ten patients with biopsy-proven NASH were included. Subjects were given 500 mg probucol daily. Liver biopsies were performed before treatment and after one year. RESULTS: Eight patients completed treatment. The mean alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels decreased from 94 and 55 to 41 and 26, respectively (P = 0.004 and 0.001 respectively). The scores for hepatic steatosis and necroinflammation decreased from 7.4 to 5.6 (P = 0.03). The fibrosis score changed from 1.1 to 1.3 (P = 0.79). No adverse drug effects were observed. CONCLUSION: Probucol is effective in normalizing aminotransferase levels in patients with NASH. It also significantly reduces the histology grade of steatohepatitis after one year of treatment. 相似文献
97.
Shahin Merat Shadi Khalili Pardise Mostajabi Anahita Ghorbani Reza Ansari Reza Malekzadeh 《Digestive diseases and sciences》2010,55(5):1385-1390
Herbal remedies, particularly peppermint, have been reported to be helpful in controlling symptoms of irritable bowel syndrome
(IBS). We conducted a randomized double-blind placebo-controlled study on 90 outpatients with IBS. Subjects took one capsule
of enteric-coated, delayed-release peppermint oil (Colpermin) or placebo three times daily for 8 weeks. We visited patients
after the first, fourth, and eighth weeks and evaluated their symptoms and quality of life. The number of subjects free from
abdominal pain or discomfort changed from 0 at week 0 to 14 at week 8 in the Colpermin group and from 0 to 6 in controls (P < 0.001). The severity of abdominal pain was also reduced significantly in the Colpermin group as compared to controls. Furthermore,
Colpermin significantly improved the quality of life. There was no significant adverse reaction. Colpermin is effective and
safe as a therapeutic agent in patients with IBS suffering from abdominal pain or discomfort. 相似文献
98.
Macleod IJ O'Donnell B Moyo S Lockman S Shapiro RL Kayembe M van Widenfelt E Makhema J Essex M Wester C 《Journal of medical virology》2011,83(10):1689-1695
Human papillomaviruses (HPV) constitute one of the most prevalent sexually transmitted infections and are the etiological agents for invasive cervical cancer, the predominant cancer among women in Botswana. However, the prevalence of HPV genotypes in Botswana has yet to be reported. One hundred thirty‐nine endocervical swabs were taken at baseline from HIV‐1 infected, HSV‐2 seropositive women enrolled in a longitudinal cohort study designed to assess the influence of herpes simplex virus‐2 (HSV‐2) infection on genital tract shedding of HIV‐1. Extracted DNA was evaluated for the presence of low‐risk and high‐risk HPV using the Roche Linear Array. Genotyping identified HPV in 95 of 139 women of which 61/95 were infected with high‐risk HPV and 56/95 with low‐risk HPV. The median number of genotypes was 2 (IQR: 1–4). The most prevalent HPV genotype in HIV‐infected women was HPV 58. Abnormal cervical cytology was detected in 87/127 women and was associated with contemporaneous HPV infection (RR = 1.43, 95% CI: 1.05–1.93; P = 0.02). HPV prevalence was high among HIV‐infected women with infection by multiple genotypes being widespread. The associations attributed to specific oncogenic HPV subtypes and cervical squamous intraepithelial lesions presented here provide critical information to inform future vaccine policy within Botswana. J. Med. Virol. 83:1689–1695, 2011. © 2011 Wiley‐Liss, Inc. 相似文献
99.
Locatelli M Caroli M Pluderi M Motta F Gaini SM Tschabitscher M Scarone P 《Surgical and radiologic anatomy : SRA》2011,33(3):257-262
Purpose
The endoscopic transnasal, transsphenoidal approach is considered by many a valid option to reach the sellar region and, in selected cases, to decompress the optic nerve. However, few data are available in literature about the real effectiveness of the procedure and the extent of nerve decompression needed to obtain a clinical result. The aim of this anatomical study was to describe the most important landmarks of the endoscopic transsphenoidal approach to the optic nerve. 相似文献100.
Arzu Oezcelik Jeffrey A. Hagen James M. Halls Jessica M. Leers Emmanuele Abate Shahin Ayazi Joerg Zehetner Steven R. DeMeester Farzaneh Banki John C. Lipham Tom R. DeMeester 《Journal of gastrointestinal surgery》2009,13(1):14-18
Introduction The timed barium study (TBS) is used to assess esophageal emptying in patients with achalasia. Improvement in emptying correlates
with outcome after endoscopic therapy, but the results of the TBS have been variable after myotomy. Our aim was to evaluate
a new method for assessing improvement in emptying after myotomy.
Methods A TBS was performed before and 3–6 months after myotomy in 30 patients. Emptying was assessed by measuring the percent difference
in area of the barium column on films obtained 1 and 5 min after ingesting 150 ml of barium. Initial esophageal clearance
was also assessed by comparing the area of the barium column on 1-min images obtained before and after therapy. Both measures
were compared to clinical outcome.
Results After myotomy, 21 patients (70%) had no symptoms, four (13%) had mild, and five (17%) had moderate/severe symptoms. Using
the standard method, esophageal emptying before and after surgery were not significantly different (25% vs. 37%; p = 0.22) and did not correlate with clinical outcome. In contrast, initial esophageal clearance improved significantly (median
81%) and correlated with clinical outcome.
Conclusion Esophageal emptying measured by the standard method is not useful to assess outcome after myotomy. However, initial esophageal
clearance correlates well with clinical outcome.
Previous presentations: 49th SSAT Annual Meeting at Digestive Disease Week, San Diego, 2008 and 23rd Annual SSAT Residents
and Fellows Research Conference, San Diego, 2008 相似文献