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1.
Overpressure blast-wave induced brain injury (OBI) leads to progressive pathophysiologic changes resulting in a reduction in brain blood flow, blood brain barrier breakdown, edema, and cerebral ischemia. The aim of this study was to evaluate cerebral vascular function after single and repeated OBI. Male Sprague-Dawley rats were divided into three groups: Control (Naive), single OBI (30 psi peak pressure, 1 to 2 msec duration), and repeated (days 1, 4, and 7) OBI (r-OBI). Rats were killed 24 hours after injury and the basilar artery was isolated, cannulated, and pressurized (90 cm H2O). Vascular responses to potassium chloride (KCl) (30 to 100 mmol/L), endothelin-1 (10−12 to 107 mol/L), acetylcholine (ACh) (1010 to 104 mol/L) and diethylamine-NONO-ate (DEA-NONO-ate) (10−10 to 104 mol/L) were evaluated. The OBI resulted in an increase in the contractile responses to endothelin and a decrease in the relaxant responses to ACh in both single and r-OBI groups. However, impaired DEA-NONO-ate-induced vasodilation and increased wall thickness to lumen ratio were observed only in the r-OBI group. The endothelin-1 type A (ETA) receptor and endothelial nitric oxide synthase (eNOS) immunoreactivity were significantly enhanced by OBI. These findings indicate that both single and r-OBI impairs cerebral vascular endothelium-dependent dilation, potentially a consequence of endothelial dysfunction and/or vascular remodelling in basilar arteries after OBI.  相似文献   
2.
Legg‐Calvé‐Perthes disease (LCPD) is a childhood hip disorder of ischemic osteonecrosis of the femoral head. Hip joint synovitis is a common feature of LCPD, but the nature and pathophysiology of the synovitis remain unknown. The purpose of this study was to determine the chronicity of the synovitis and the inflammatory cytokines present in the synovial fluid at an active stage of LCPD. Serial MRI was performed on 28 patients. T2‐weighted and gadolinium‐enhanced MR images were used to assess synovial effusion and synovial enhancement (hyperemia) over time. A multiple‐cytokine assay was used to determine the levels of 27 inflammatory cytokines and related factors present in the synovial fluid from 13 patients. MRI analysis showed fold increases of 5.0 ± 3.3 and 3.1 ± 2.1 in the synovial fluid volume in the affected hip compared to the unaffected hip at the initial and the last follow‐up MRI, respectively. The mean duration between the initial and the last MRI was 17.7 ± 8.3 months. The volume of enhanced synovium on the contrast MRI was increased 16.5 ± 8.5 fold and 6.3 ± 5.6 fold in the affected hip compared to the unaffected hip at the initial MRI and the last follow‐up MRI, respectively. In the synovial fluid of the affected hips, IL‐6 protein levels were significantly increased (LCPD: 509 ± 519 pg/mL, non‐LCPD: 19 ± 22 pg/mL; p = 0.0005) on the multi‐cytokine assay. Interestingly, IL‐1β and TNF‐α levels were not elevated. In the active stage of LCPD, chronic hip synovitis and significant elevation of IL‐6 are produced in the synovial fluid. Further studies are warranted to investigate the role of IL‐6 on the pathophysiology of synovitis in LCPD and how it affects bone healing. © 2015 American Society for Bone and Mineral Research  相似文献   
3.
We investigated the prostate cancer detection rates upon transrectal ultrasound (TRUS)-guided biopsy in relation to digital rectal examination (DRE) and prostate-specific antigen (PSA), and risk factors of prostate cancer detection in the Chinese population. Data from all consecutive Chinese men who underwent first TRUS-guided prostate biopsy from year 2000 to 2013 was retrieved from our database. The prostate cancer detection rates with reference to DRE finding and PSA level of < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 were investigated. Multivariate logistic regression analyses were performed to investigate for potential risk factors of prostate cancer detection. A total of 2606 Chinese men were included. In patients with normal DRE, the cancer detection rates were 8.6%, 13.4%, 21.8%, 41.7% and 85.2% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. In patients with abnormal DRE, the cancer detection rates were 12.4%, 30.2%, 52.7%, 80.6% and 96.4% in patients with PSA < 4, 4–10, 10.1–20, 20.1–50 and > 50 ng ml−1 respectively. Older age, smaller prostate volume, larger number of biopsy cores, presence of abnormal DRE finding and higher PSA level were associated with increased risk of prostate cancer detection upon multivariate logistic regression analyses (P < 0.001). Chinese men appeared to have lower prostate cancer detection rates when compared to the Western population. Taking the different risk factors into account, an individualized approach to the decision of TRUS-guided biopsy can be adopted.  相似文献   
4.
5.
BACKGROUND: Platelets become activated during storage, which results in secretion of granules, vesiculation of microparticles, secretion of protein, and a number of other biochemical and morphologic processes that decrease the utility of platelet concentrates stored for transfusion. STUDY DESIGN AND METHODS: To evaluate the quality of stored platelet concentrates, the cell surface expression of specific activation-dependent antigens (CD62 and lysosome-associated membrane proteins 1 and 2 [LAMP-1, LAMP-2]) on platelets stored in a hospital blood bank over a 7-day period was examined. Relative microparticle counts and the expression of CD62 by microparticles, as well as platelet concentrate supernatant levels of soluble CD62, were determined. RESULTS: The percentage of platelets expressing CD62 increased significantly from Day 1 to Day 5 (p < 0.05) of storage; the mean fluorescence values for CD62 did not. In contrast, the mean fluorescence values of LAMP-1 and LAMP-2 rose significantly (p < 0.01 and p < 0.05, respectively) between Days 1 and 5. Significant declines in CD62, LAMP-1, and LAMP-2 percent expression and mean fluorescence were seen on Day 6 of storage (p < 0.001). Microparticle numbers increased significantly during storage and correlated with levels of CD62 protein (free and membrane-bound) (r = 0.95 vs. Day 2, p < 0.05; r = 0.88 vs. Day 5, p < 0.05). CONCLUSION: Flow cytometric evaluations of the expression of cell surface CD62, LAMP-1, and LAMP-2 are complementary tests that, especially when used in conjunction with the quantitation of CD62 protein, provided a simple and effective means of evaluating the quality of platelet concentrates stored for transfusion.  相似文献   
6.
ObjectiveBilateral oophorectomy leads to reduced bone mineral density (BMD), and reduced BMD is associated with increased marrow fat and reduced marrow perfusion. Purpose of this study was to investigate how soon these changes occur following surgical oophorectomy.ResultsReduced BMD, increased marrow FF, and reduced marrow perfusion occurred synchronously post-oophorectomy. There was a sharp decrease of 12.5 ± 7.2% in BMD (n = 6), a sharp increase of 92.2 ± 46.3% (n = 6) in FF, a sharp decrease of 23.6 ± 3.9% in maximum contrast enhancement (n = 5), and of 45.4 ± 7.7% for enhancement slope (n = 5) during the initial 3 months post surgery. BMD and marrow perfusion continued to decrease, and marrow FF continued to increase at a slower rate during the following 18 months. Friedman test showed a significant trend for these changes (p < 0.05).ConclusionBilateral oophorectomy leads to a rapid decrease in lumbar BMD, an increase in marrow fat content, and a decrease in marrow blood perfusion.  相似文献   
7.

Back ground

Stroke produces a wide range of mental and emotional disorders. Neuropsychiatric complications associated with stroke may have negative effects on the social functioning, overall quality of life and the recovery of motor functioning of stroke survivors.

Objective

To determine the prevalence and nature of psychiatric morbidity among stroke patients attending neurology outpatient clinic of the University of Ilorin Teaching Hospital (UITH), Ilorin-Nigeria.

Methods

All patients with stroke aged 18 years and above at an outpatient neurology clinic in Ilorin, Nigeria were assessed for mental and emotional disorders using the Schedule for Clinical Assessment in Neuropsychiatry (SCAN) over one year (March 2009 to February 2010).

Results

Overall prevalence of psychiatric morbidity was 36.0% (30/83) among 83 patients who constituted the study population. Specific diagnoses recorded were depression (19.2%), generalised anxiety disorder (9.6%), harmful alcohol use (2.4%); dementia, somatoform disorder, phobia and delusional disorder each had a prevalence of 1.2%. Clinical and sociodemographic variables were not significantly associated with psychiatric morbidity.

Conclusion

Psychiatric disorders are often associated with stroke. Identifying and treating stroke patients with these psychiatric co-morbidities could thus help to improve the overall quality of life of these patients.  相似文献   
8.
目的在甲状腺手术中缺少术中神经监测(intra operative neuromonitoring,IONM)的标准化操作可导致结果变异性强,这些结果可产生错误信息并增加喉返神经损伤的危险性。因此有必要进行IONM操作的标准化。方法本研究共招募了289例进行过甲状腺切除术的患者(435根神经有危险),均由一位外科医师实施手术。每例患者均由同一位麻醉师使用EMG气管导管进行插管。每例患者均进行标准化IONM操作。该操作包括术前和术后对声带运动进行录像监测、保证电极在正确位置、喉返神经剥离前后刺激迷走神经并记录EMG信号,并摄像记录暴露的喉返神经。结果5例患者出现IONM波形异常,是由于电极错位所致,这一问题被立刻监测到。监测到1例患者在手术较早阶段出现非喉返神经损伤。甲状腺剥离时18例患者的神经失去了EMG信号,使用我们的标准化IONM操作后神经损伤的原因得以清楚阐明。结论标准化IONM操作不仅在消除错误的IONM结果方面有用且有帮助,而且有助于阐明喉返神经损伤的机制。在确定外科手术的缺陷并提高外科手术技巧后,本研究显著降低了神经麻痹的发生率。  相似文献   
9.
Solary  E; Bertrand  R; Kohn  KW; Pommier  Y 《Blood》1993,81(5):1359-1368
The effects of monocytic/macrophage and granulocytic differentiation induced by phorbol myristate acetate (TPA) and all-trans retinoic acid, respectively, were tested on the induction of apoptosis in human promyelocytic leukemia HL-60 cells treated with topoisomerase I and II inhibitors. Using a filter-binding assay, we observed a strong inhibition of DNA fragmentation induced by 3- and 24-hour continuous exposure to camptothecin, VP-16, VM-26, and m-AMSA in TPA- differentiated cells. The inhibition of the typical internucleosomal DNA fragmentation was confirmed by agarose gel electrophoresis. By contrast, drug-induced DNA fragmentation was not inhibited in retinoic acid-differentiated cells, and apoptosis occurred in these cells after 4 to 5 days in the absence of drug treatment. The TPA inhibitory effect was maximal after 24 hours of treatment and was correlated with differentiation, because phorbol dibutyrate ester was active, whereas 4- alpha-TPA, a nontumor promoter that does not induce differentiation, was not active. Using alkaline elution, we observed that TPA and retinoic acid differentiation were associated with changes in topoisomerase-mediated DNA breaks that were not correlated with their differential effects on drug-induced DNA fragmentation. Moreover, TPA also inhibited DNA fragmentation induced by vinblastine, cycloheximide, calphostin C, and x-rays. Using a cell-free system, we observed that DNA fragmentation was not inhibited in nuclei from TPA-differentiated cells. Rather, inhibition of apoptosis seemed to take place in the cytoplasm. We conclude that phenotypic changes associated with TPA- induced differentiation include inactivation of a cytoplasmic activity that can induce DNA fragmentation associated with apoptosis.  相似文献   
10.

Background:

The surgeon''s contribution to patients with localized pancreatic adenocarcinoma (PAC) is a margin negative (R0) resection. We hypothesized that a prediction rule based on pre-operative imaging would maximize the R0 resection rate while reducing non-therapeutic intervention.

Methods:

The prediction rule was developed using computed tomography (CT) and endoscopic ultrasound (EUS) data from 65 patients with biopsy-proven PAC who underwent attempted resection. The rule classified patients as low or high risk for non-R0 outcome and was validated in 78 subsequent patients.

Results:

Model variables were: any evidence of vascular involvement on CT; EUS stage and EUS size dichotomized at 2.6 cm. In the validation cohort, 77% underwent resection and 58% achieved R0 status. If only patients in the low-risk group underwent surgery, the prediction rule would have increased the resection rate to 92% and the R0 rate to 73%. The R0 rate was 40% higher in low-risk compared with high-risk patients (P < 0.001). High risk was associated with a 67% rate of non-curative surgery (unresectable disease and metastases).

Conclusion:

The prediction rule identified patients most likely to benefit from resection for PAC using pre-operative CT and EUS findings. Model predictions would have increased the R0 rate and reduced non-therapeutic interventions.  相似文献   
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