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91.

Objective

The aim of this study was to address the question of whether bone marrow-originated mononuclear cells (MNC) or mesenchymal stem cells (MSC) induce neural regeneration when implanted intraspinally.

Materials and Methods

The study design included 4 groups of mice: Group 1, non-traumatized control group; Groups 2, 3 and 4 spinal cord traumatized mice with 1 g force Tator clips, which received intralesionally either no cellular implants (Group 2), luciferase (Luc) (+) MNC (Group 3) or MSC (Group 4) obtained from CMV-Luc or beta-actin Luc donor transgenic mice. Following the surgery until decapitation, periodical radioluminescence imaging (RLI) and Basso Mouse Scale (BMS) evaluations was performed to monitor neural activity. Postmortem immunohistochemical techniques were used to analyze the fate of donor type implanted cells.

Results

All mice of Groups 3 and 4 showed various degrees of improvement in the BMS scores, whereas there was no change in Groups 1 and 2. The functional improvement was significantly better in Group 4 compared to Group 3 (18 vs 8, p?=?0.002). The immunohistochemical staining demonstrated GFP+Luc+ neuronal/glial cells that were also positive with one or more of these markers: nestin, myelin associated glycoprotein, microtubule associated protein or myelin oligodendrocyte specific protein, which is considered as indicator of donor type neuronal regeneration. Frequency of donor type neuronal cells; Luc + signals and median BMS scores were observed 48–64 % and 68–72 %; 44–80 %; 8 and 18 within Groups III and IV respectively.

Discussion

MSCs were more effective than MNC in obtaining neuronal recovery. Substantial but incomplete functional improvement was associated with donor type in vivo imaging signals more frequently than the number of neuronal cells expressing donor markers in spinal cord sections in vitro. Our results are in favor of functional recovery arising from both donor MSC and MNCs, contributing to direct neuronal regeneration and additional indirect mechanisms.  相似文献   
92.
Although T and B cell alloimmunity contribute to transplant injury, autoimmunity directed at kidney-expressed, non-HLA antigens may also participate. Because the specificity, prevalence, and importance of antibodies to non-HLA antigens in late allograft injury are poorly characterized, we used a protein microarray to compare antibody repertoires in pre- and post-transplant sera from several cohorts of patients with and without transplant glomerulopathy. Transplantation routinely induced changes in antibody repertoires, but we did not identify any de novo non-HLA antibodies common to patients with transplant glomerulopathy. The screening studies identified three reactivities present before transplantation that persisted after transplant and strongly associated with transplant glomerulopathy. ELISA confirmed that reactivity against peroxisomal-trans-2-enoyl-coA-reductase strongly associated with the development of transplant glomerulopathy in independent validation sets. In addition to providing insight into effects of transplantation on non-HLA antibody repertoires, these results suggest that pretransplant serum antibodies to peroxisomal-trans-2-enoyl-coA-reductase may predict prognosis in kidney transplantation.  相似文献   
93.
94.
Pseudoexfoliation syndrome (PEX) is the most common clinical precursor of open-angle glaucoma. Recent studies have shown that pseudoexfoliative material is widely distributed throughout the body, including blood vessels. The aim of our study was to evaluate endothelial function in the brachial artery of patients with pseudoexfoliation syndrome. We prospectively examined 23 patients with PEX (mean age, 70 +/- 8 years) and 20 healthy age- and sex-matched individuals (mean age, 68 +/- 9 years) as a control group. Brachial artery endothelial function was assessed by vascular response to reactive hyperemia (flow-mediated dilation (FMD) and sublingual nitroglycerin (NTG-mediated dilation) using high-resolution ultrasound. Flow-mediated and NTG-induced dilation were expressed as the percent change in diameter after reactive hyperemia and after NTG administration relative to the baseline value, respectively. Patients with cardiovascular disease and other conditions associated with endothelial dysfunction were excluded. When compared with controls, patients with PEX had significantly lower flow-mediated dilation (4.5 +/- 2.8 versus 8.2 +/- 3.7, P = 0.01) and NTG-mediated dilation (10.9 +/- 3.1 versus 15.8 +/- 3.8, P = 0.0001). Flow-mediated dilation and NTG-mediated dilation were similar in PEX patients with glaucoma (n = 11) and without glaucoma (n = 12). Flow-mediated and NTG-mediated dilation did not correlate with any measured parameter in any patient or control subject. The findings indicate that systemic endothelial function is impaired in PEX syndrome patients.  相似文献   
95.
BackgroundWe conducted this prospective study to evaluate the efficacy of percutaneous catheter drainage as a minimally invasive treatment in the management of symptomatic bile leak following biliary injuries associated with laparoscopic cholecystectomy.MethodsTwenty two patients with symptomatic bile leak following laparoscopic cholecystectomy underwent percutaneous drainage of the bile collection under ultrasound control. In patients with jaundice and in those with persistent drainage, endoscopic retrograde cholecysto-pancreatography (ERCP) was performed immediately for diagnostic and for therapeutic intervention when appropriate. In other patients, ERCP was performed 4–6 weeks after the discharge from the hospital to document the healing of the leaking site.ResultsFive patients with jaundice were initially treated by a combination of endoscopic plus percutaneous drainage. One of them required surgical treatment following diagnosis of a major duct injury. The other 17 were treated by percutaneous drainage initially and for 14 of them it was definitive treatment. Three patients required sphincterotomy as additional treatment for stopping the leak. There were no complications related to the percutaneous drainage procedure.ConclusionsMost patients with bile leakage can be managed successfully by percutaneous drainage. If biliary output does not decrease, endoscopy is needed. In patients with jaundice endoscopic diagnostic and therapeutic procedures should be performed immediately.  相似文献   
96.
This study was designed to examine the relationship between pericardial fluid and plasma CRP levels, and to alterations in other biochemical parameters in patients undergoing Coronary Artery Bypass Grafting (CABG). The study group consisted of 96 Coronary Artery Disease (CAD) patients who were referred to our clinic for a CABG procedure and from whom sufficient amount of pericardial fluid could be collected. The patients were classified into 3 groups: Stable Angina Pectoris (SAP) (n=27), Unstable Angina Pectoris (USAP) (n=36), and Post-Myocardial Infarction (PMI) (n=33). Levels of CRP, glucose, albumin, total protein, Creatine Kinase (CK), Creatine Kinase-MB (CK-MB), and Lactate Dehydrogenase (LDH) were determined in pericardial fluid samples and in simultaneously collected blood samples from radial artery. The pericardial CRP and LDH levels in the PMI group were higher than in the SAP (p=0.015 and p=0.000, respectively) and USAP (p=0.011, p=0.047) groups. Serum CRP levels in USAP (p=0.014) and PMI (p= 0.000) groups were higher than those in the SAP group. Pericardial albumin levels in the PMI group were higher than in the USAP group (p=0.038). In all groups, the pericardial fluid/serum protein ratio was > 0.5, the LDL ratio was > 0.6, and pericardial fluid LDH concentrations were > 300 mg/dl. CRP level of pericardial fluid was significantly higher in the PMI group than in other groups. However, pericardial fluid LDH levels were higher than blood LDH levels in this group and were also higher than pericardial fluid LDH levels of other groups.  相似文献   
97.
Klippel-Trenaunay syndrome (KTS) manifests cutaneous vascular nevus, superficial venous varicosities, and hypertrophy of the affected limb. KTS may be associated with other developmental anomalies such as polydactyly, syndactyly, and macrocephaly. We present a case with KTS associated with polydactyly.  相似文献   
98.
99.
L-carnitine (LC) protects cells from peroxidative damage. In this study, we tested whether L-carnitine (LC) prevents radiation-induced cochlear damage after total cranial irradiation (radiotherapy; RT). Male albino guinea pigs were randomly distributed in 3 groups. The Control group (n = 11) received neither LC nor irradiation, but saline solution ip and sham irradiation for 5 days. The RT group (n = 32) received saline solution ip as placebo therapy and exposure to total cranial irradiation of 33 Gy in 5 fractions of 6.6 Gy/day on 5 successive days, with a calculated (alpha/beta = 3.5) biological effective dose of fractionated irradiation equal to 60 Gy conventional fractionation. The LC + RT group (n = 36) received total cranial irradiation, plus LC (100 mg/kg/day, ip) for 5 days. The guinea pigs were killed at 4, 24, or 96 hr after the last dose of RT and the cochleas were enucleated for histopathologic examination. There was no cochlear degeneration in the control group. In the RT group, total cranial irradiation caused degeneration in stria vascularis (SV), spiral ganglion (SG), outer hair cells (OHC), and inner hair cells (IHC) of cochleas at 4, 24, and 96 hr. In the LC + RT group, LC administration reduced radiation-induced cochlear degeneration in SV and SG at 4, 24, and 96 hr, and in OHC and IHC at 24 and 96 hr (p <0.05). Thus, this study shows that L-carnitine can ameliorate radiation-induced cochlear damage in guinea pigs.  相似文献   
100.
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