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991.
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Loss of dopaminergic neurons in the substantia nigra (A9 cells) and ventral tegmental area (VTA) (A10 cells) has been reported in Parkinson's disease with reference to causing motor and non-motor deficits, although clinical and laboratory animal studies on the degeneration of VTA neurons are less emphasized comparative to the degeneration of substantia nigra neurons. In the present study, we examined the VTA dopaminergic neurons in a chronic mouse model of Parkinson's disease induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine and probenecid at a level showing moderate neurodegeneration and studied the impact of endurance exercise on VTA neurons in this model. In comparison to the normal control animals, the chronic mouse model of Parkinson's disease with moderate neurodegeneration demonstrated a significant reduction of VTA neurons (52% loss), when these animals were kept sedentary throughout the study. Morphologically, the VTA dopaminergic neurons in this model displayed a decrease in cell volume and showed irregular or disparaging axonal and dendritic projections. When the chronic Parkinsonian mice were exercised on a motorized rodent treadmill up to 15 m/min, 40 min/day, 5 days/week for 10 and 18 weeks, the total number of VTA dopaminergic neurons were significantly higher than the sedentary Parkinsonian animals. Especially noted with the 18-week exercised Parkinsonian mice, the number of VTA neurons returned to normal range and the cells were densely populated and displayed distinctive axons and dendritic arborization. These results demonstrate that prolonged exercise training is neuroprotective to the dopaminergic neurons in the VTA of the chronic mouse model of Parkinson's disease with moderate neurodegeneration. 相似文献
994.
Hamid Reza Jamaati Mohammad Behgam Shadmehr Bahare Saidi Adnan Khosravi Mehrdad Arab Forouzan Mohammadi 《Endocrine pathology》2009,20(2):133-136
A 24-year-old man presented to our center with a huge goiter compressing his airway. He had a previous diagnosis of Langerhans
cell histiocytosis (LCH) of the lung. Core needle biopsy was consistent with histiocytosis. Thyroidectomy was performed. A
very invasive mass was encountered at the time of surgery. Histopathology result was consistent with an invasive papillary
cancer of thyroid co-occurring with LCH. Although association of LCH with different malignancies has been reported, co-existing
invasive papillary thyroid cancer and LCH is a rare combination. 相似文献
995.
Shaghayegh Haghjooy Javanmard Mehdi Nematbakhsh Farzaneh Mahmoodi Mohamad Reza Mohajeri 《Pathophysiology》2009,16(1):9-13
Introduction: Diminished bioavailability of nitric oxide is crucial in endothelial dysfunction and the development of atherosclerosis. Several studies have found that l-arginine as a nitric oxide (NO) donor has beneficial effect in prevention of atherosclerosis, but the mechanism is not completely known. We hypothesized that increased endothelial nitric oxide synthase (eNOS) and/or decreased inducible NOS (iNOS) expressions might be involved in the preventive effects of l-arginine in hypercholesterolemic rabbits. Methods: Seventeen male rabbits were divided randomly in two groups. They received rabbits chow supplemented with 1% cholesterol (group 1, n = 8) and the other group received also l-arginine (3% in drinking water) (group 2, n = 9) for 1 month. Blood samples were obtained before and after the experiment. At the end of experiment, the aortas were harvested. The serum levels of cholesterol and low-density lipoproteins (LDL) were measured. The intima/media thickness (IMT) ratio was measured and the determination of fatty streak formation was done with the aid of light microscopy. eNOS and iNOS expression in aorta were studied with immuohistochemistery. Results: The IMT ratio in first group having fatty streaks was 0.287 ± 0.15. No fatty streak lesion was detected in l-arginine-treated group. The results also indicated that eNOS expression (intensity) in aortas was significantly higher in l-arginine-treated group (group 1: 13.62 ± 2.7 and group 2: 21.77 ± 2.8; p < 0.05), but no significant difference was observed for iNOS expression between the groups. Conclusion: The expression of eNOS plays an important role in the protection of the vessel wall from atherosclerosis. l-Arginine in drinking water has a beneficial effect in the enhancement of eNOS protein expression. 相似文献
996.
Nutrition in severe acute pancreatitis is a critical aspect in the management of this condition. This review aims to systematically review the evidence available to inform the use of nutritional support in severe acute pancreatitis. High quality (level 1) evidence supports naso–jejunal enteral nutrition (NJ-EN) over parenteral nutrition (PN) reducing infectious morbidity and showing a trend towards reduced organ failure although there is no detectable difference in mortality. Trial data may underestimate benefit as patients are often recruited with predicted rather than proven severe disease. NJ-EN is safe when started immediately (level 3 evidence). NJ-EN is often impractical and naso-gastric (NG) feeding seems to be equivalent in terms of safety and outcomes whilst being more practical (level 2 evidence).Regarding feed supplementation, probiotic feed supplementation is not beneficial (level 1 evidence) the and may cause harm with excess mortality (level 2 evidence). No evidence exists to confirm benefit of the addition of prokinetics in severe acute pancreatitis (SAP) although their use is proven in other critically ill patients. Level 2 evidence does not currently support the use of combination immuno-nutrition though further work on individual agents may provide differing results. Level 2 evidence does not support intravenous supplementation of anti-oxidants and has demonstrated that these too may cause harm. 相似文献
997.
Sameer M. Alarrayed Amgad E. El-Agroudy Ahmad S. Alarrayed Sumaya M. Al Ghareeb Taysir S. Garadah Salah Y. El-Sharqawi Ali H. Al-Aradi Balaji G. Dandi Sadiq Abdulla 《Clinical and experimental nephrology》2010,14(3):248-255
Background/aim
This observational study was conducted to evaluate the safety and efficacy of the conversion from calcineurin inhibitors (CNIs) to sirolimus (SRL)-based immunosuppressive therapy in kidney transplantation. 相似文献998.
Mohammad Reza Hasanjani Roushan Mohammad Jafar Soleimani Amiri Abolghasem Laly Amrollah Mostafazadeh A. Bijani 《International journal of infectious diseases》2010,14(3):e250-e253
BackgroundThe standard agglutination (SAT) and 2-mercaptoethanol (2-ME) tests are usually used in the follow-up of treated cases of human brucellosis. The purpose of this study was to monitor the levels of these tests, two years after clinical cure in cases of brucellosis.MethodsFrom April 2003 to September 2008, 175 clinically cured cases of brucellosis (103 males, 72 females) were evaluated. Diagnosis of brucellosis was established with a SAT of ≥1:320 and a 2-ME of ≥1:80, with clinical symptoms and signs compatible with brucellosis. SAT and 2-ME were retested at the end of therapy and at 3-monthly intervals for two years. Serologic cure was considered in the event of a SAT titer decrease to ≤1:160 or a 2-ME decrease to < 1:80.ResultsThe mean age of study patients was 31 ± 13.5 years. At 6, 12, 18, and 24 months after treatment, SAT titers ≥1:320 were seen in 41 (23.4%), 22 (12.6%), 7 (4%), and 6 (3.4%) cases, respectively, whereas 2-ME titers ≥1:80 were seen in 51 (29.1%), 24 (13.7%), 12 (6.9%), and 8 (4.6%) cases, respectively. The probability of serologic cure for patients with SAT titers ≤1:640 was higher than for those >1:640 (95% confidence interval (CI) 2.5–3.47, p = 0.023). The probability of serologic cure for patients with 2-ME titers ≤1:320 was higher than for those >1:320 (95% CI 2.48–3.5, p = 0.04).ConclusionsSAT and 2-ME may be found in significant titers in less than 5% of clinically treated cases after two years. Serologic cure for both tests with lower titers were higher than with higher titers. 相似文献
999.
Husain A. Saleh M.D. F.I.A.C. M.B.A. Mohammad El‐Fakharany M.D. Hassan Makki M.D. F.C.C.P. Ahmad Kadhim M.D. Shahla Masood M.D. 《Diagnostic cytopathology》2009,37(5):324-332
Differentiating reactive mesothelial cells (RMs) from metastatic adenocarcinoma cells (MAC) in serous fluids based on cytomorphologic features alone can be very challenging. Various immunocytochemical (ICC) markers have been used to maximize the diagnostic accuracy, however, cytopathologists still encounter difficulties in effusion cytologic diagnosis. The aim of this study was to evaluate previous and recent ICC stains to identify the most sensitive and specific markers and the best panel for differentiating RM from MAC. Cell block sections from 41 MAC and 43 RM effusions cases were subjected to ICC staining for MOC‐31, BerEp4, carcinoembryonic antigen (CEA), calretinin, HBME‐1, CK5/6, and D2‐40. For the MAC cases, the sensitivity of BerEp4, MOC‐31, and CEA was 82.9, 92.6, and 17%, respectively, and the specificity was 95.3, 93, and 100%, respectively. For the RM cases, the sensitivity of calretinin, CK5/6, D2‐40, and HBME‐1 was 95.3, 27.9, 58.1, and 93%, respectively, and the specificity was 70.7, 73.1, 75.6, and 82.9%, respectively. The results show that BerEp4 and MOC‐31 are highly sensitive and specific for detecting MAC, whereas calretinin and HBME1 are highly sensitive but only modestly specific for detecting RM cases (P < 0.05). Forced entry logistic regression revealed that using MOC‐31, BerEp4, HBME‐1, and calretinin, is an excellent panel for making correct diagnosis with 97.6% sensitivity in detecting MAC and 90.7% specificity in detecting RM. We conclude that adding a panel of MOC‐31, BerEp4, calretinin, and HBME‐1 immunostains to routine cytomorphologic features can greatly enhance the diagnostic accuracy of serous effusions. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc. 相似文献
1000.