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31.

Background

Among the strategies to increase the number of lung transplants, ex vivo lung perfusion (EVLP) represents a novel technique to expand the donor pool.

Methods

Data from donors referred to our center were retrospectively analyzed to identify grafts that could potentially be potentially reconditioned by EVLP and for comparison with those obtained by clinical application of EVLP program in our center.

Results

Among 75 rejected lungs, 23 organs have been identified as potentially treatable with EVLP with a hypothetic increase of lung transplant activity of 53%. After the introduction of the EVLP program in our center, lung transplantation with reconditioned grafts was performed in 7 (23%) patients with a 30% increase in transplant procedures.

Conclusion

Although less than expected, EVLP increased the number of lungs suitable for transplantation.  相似文献   
32.
PurposeTo explore the effect of gaze direction and eyelid closure on intraocular pressure (IOP).MethodsEleven patients with primary open-angle glaucoma previously implanted with a telemetric IOP sensor were instructed to view eight equally-spaced fixation targets each at three eccentricities (10°, 20°, and 25°). Nine patients also performed eyelid closure. IOP was recorded via an external antenna placed around the study eye. Differences of mean IOP between consecutive gaze positions were calculated. Furthermore, the effect of eyelid closure on gaze-dependent IOP was assessed.ResultsThe maximum IOP increase was observed at 25° superior gaze (mean ± SD: 4.4 ± 4.9 mm Hg) and maximum decrease at 25° inferonasal gaze (−1.6 ± 0.8 mm Hg). There was a significant interaction between gaze direction and eccentricity (P = 0.003). Post-hoc tests confirmed significant decreases inferonasally for all eccentricities (mean ± SEM: 10°: −0.7 ± 0.2, P = 0.007; 20°: −1.1 ± 0.2, P = 0.006; and 25°: −1.6 ± 0.2, P = 0.006). Eight of 11 eyes showed significant IOP differences between superior and inferonasal gaze at 25°. IOP decreased during eyelid closure, which was significantly lower than downgaze at 25° (mean ± SEM: −2.1 ± 0.3 mm Hg vs. −0.7 ± 0.2 mm Hg, P = 0.014).ConclusionsOur data suggest that IOP varies reproducibly with gaze direction, albeit with patient variability. IOP generally increased in upgaze but decreased in inferonasal gaze and on eyelid closure. Future studies should investigate the patient variability and IOP dynamics.  相似文献   
33.
34.

Background

Genetic risk factors play an important role in the pathogenesis of Alzheimer's disease (AD). In this case-control study, we examined the C677T and A1298C polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene and their correlation with this pathology.

Objective

To verify the association between MTHFR C677T and A1298C polymorphisms and Alzheimer's disease.

Method

This work was conducted as a case–control study. Cases consisted of thirty-eight patients and 100 individuals without dementia constituted the control group. Genotyping of MTHFR polymorphisms was performed on patients and controls.

Result

Genetic analyses did not indicate a significant association between the MTHFR C677T mutation and AD (C/T: 63.15% versus 39%, p = 0.087). However, the genotype prevalence of the missense variant MTHFR A1298C was significantly different between patients and controls (A/C: 55% versus 7%, p < 10−3). Our data suggest an association between the MTHFR A1298C mutation and AD; however, the MTHFR C677T mutation did not contribute to susceptibility for AD.

Conclusion

The MTHFR A1298C polymorphism is a possible risk factor for Alzheimer's disease.  相似文献   
35.
Exposure to cigarette smoke is emerging as an environmental risk factor for multiple sclerosis (MS). We investigated the possible association between environmental tobacco smoke, its cumulative exposure, and MS risk. We used data from the Iranian Multiple Sclerosis Registry to identify a case-control of 662 patients who had MS and a comparison group of 394 patients. Information regarding current smoking status, including the number of cigarettes smoked per day, duration, and smoking pack-years indicative of cumulative dose of tobacco smoked was obtained. We analyzed the incidence of MS among ever–smokers who had been smokers during their disease course and prior to disease onset in comparison with never–smokers who had never been exposed by calculating the odds ratio (OR) with a 95% confidence interval (CI) employing logistic regression. Of the 662 MS patients, there were 523 women (79.0%) and 139 men (21.0%), with a mean age of 31 ± 10.0 years at disease onset. The risk for MS was increased among ever–smokers (OR = 1.78, 95% CI = 1.22–2.59, p = 0.03) compared to never–smokers. As compared with never smokers, the OR for patients with 6–10 pack years was 2.91 for men (95% CI = 1.11–9.47, p = 0.03) and 1.69 for women (95% CI = 1.02–6.45, p = 0.04). Our results demonstrate that cigarette smoking is significantly associated with an increased risk for MS. The risk effects of smoking were more noticeable in male patients and at higher tobacco doses.  相似文献   
36.
Two important pathophysiological mechanisms involved during cerebral ischemia are oxidative stress and inflammation. In pathological conditions such as brain ischemia the ability of free radicals production is greater than that of elimination by endogenous antioxidative systems, so brain is highly injured due to oxidation and neuroinflammation. Fibrates as peroxisome proliferator-activated receptor (PPAR)-α ligands, are reported to have antioxidant and anti-inflammatory actions. In this study, gemfibrozil, a fibrate is investigated for its therapeutic potential against global cerebral ischemia–reperfusion (I/R) injury of male and female rats. This study particularly has focused on inflammatory and antioxidant signaling pathways, such as nuclear factor erythroid-related factor (Nrf)-2, as well as the activity of some endogenous antioxidant agents. It was found that pretreatment of animals with gemfibrozil prior to I/R resulted in a sexually dimorphic outcome. Within females it proved to be protective, modulating inflammatory factors and inducing antioxidant defense system including superoxide dismutase (SOD), catalase, as well as glutathione level. However, Nrf-2 signaling pathway was not affected. It also decreased malondialdehyde level as an index of lipid peroxidation. In contrast, gemfibrozil pretreatment was toxic to males, enhancing the expression of inflammatory factors such as tumor necrosis factor-α, nuclear factor-κB, and cyclooxygenase-2, and decreasing Nrf-2 expression and SOD activity, leading to hippocampal neurodegeneration. Considering that gemfibrozil is a commonly used anti-hyperlipidemic agent in clinic, undoubtedly more investigations are crucial to exactly unravel its sex-dependent neuroprotective/neurodegenerative potential.  相似文献   
37.
38.
The syntheses and biological studies of O-oxime ethers having α-amino acid residues as new analogs of IPS-339 have been described. In this synthesis, the reaction of fluorene and/or benzophenone O-oxime with epichlorohydrin or epibromohydrin afforded the corresponding O-oxime ether adducts. The N-alkylation of amino acid with O-oxime ether adducts led to synthesis of new analogs of IPS-339. The products were examined for their cardiovascular property. It was demonstrated that 2-(3-(9H-fluoren-9-ylideneaminooxy)-2-hydroxypropylamino)-3-methyl-butanoic acid as the most potent compound substantially reduces the heart rate of dogs. Compounds were also evaluated for their in vitro antibacterial activity against some Gram-negative and Gram-positive bacteria. The antibacterial screening proved the considerable antibacterial activity against both groups of bacteria. The docking analysis demonstrated the appropriate fitting of 2-(3-(9H-fluoren-9-ylideneaminooxy)-2-hydroxy-propylamino)-3-methyl-butanoic acid in human β2-adrenergic receptor active site. Potential drug toxicity for some active compounds has also been predicted.  相似文献   
39.
Context: Solanum xanthocarpum Schard. and Wendl. (Solanaceae) has been used in traditional Indian medicines for its antioxidant, anti-inflammatory, and antiasthmatic properties.

Objective: The present study demonstrates the antioxidant and hepatoprotective effects of S. xanthocarpum. On the basis of in vitro antioxidant properties, the active fraction from column chromatography of the methanol extract of S. xanthocarpum leaves (SXAF) was chosen as the potent fraction and used for hepatoprotective studies in rats.

Materials and methods: The antioxidant activity was evaluated by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), and reducing power assays. Rats were pre-treated with 100 and 200?mg/kg b.w. of SXAF for 14?d with a single dose of CCl4 in the last day. Hepatoprotective properties were determined by serum biochemical enzymes, aspartate transaminase (AST), alanine transaminase (ALT), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), antioxidant enzymes (SOD, CAT, GSH, and GST), and histopathology studies.

Results: SXAF exhibited significant antioxidant activity in scavenging free radicals with IC50 values of 11.72?µg (DPPH) and 17.99?µg (ABTS). Rats pre-treated with SXAF demonstrated significantly reduced levels of serum LDH (1.7-fold), ALP (1.6-fold), and AST (1.8-fold). Similarly, multiple dose SXAF administration at 200?mg/kg b.w. demonstrated significantly enhanced levels of SOD (1.78?±?0.13), CAT (34.63?±?1.98), GST (231.64?±?14.28), and GSH (8.23?±?0.48) in liver homogenates. Histopathological examination showed lowered liver damage in SXAF-treated groups.

Discussion and conclusion: These results demonstrate that SXAF possesses potent antioxidant properties as well as hepatoprotective effects against CCl4-induced hepatotoxicity.  相似文献   
40.
In order to develop a possible C-X-C chemokine receptor type 4 (CXCR4) imaging agent for oncological scintigraphy, [67Ga]-labeled 1,1′-[1,4-Phenylene-bis(methylene)]bis(1,4,8,11-tetraazacyclotetradecane) ([67Ga]-AMD3100) was prepared by using [67Ga]GaCl3 and AMD-3100 for 2 h at 50 °C (radiochemical purity: >95% ITLC, >99% HPLC, specific activity: 1800–2000 TBq/mmol) in acetate buffer. The stability of the complex was checked in the presence of human serum (37 °C) and in the final formulation for four days. The biodistribution of the labeled compound in the vital organs of wild type Sprague-Dawley rats was determined and compared with that of the free Ga3+ cation up to 48 h. Considering the spleen as the target organ, the best target:non target ratios were obtained 48 h post-injection (spleen:blood ratio; 14.5 and spleen:muscle ratio; 88.4). Initial SPECT images and biodistribution results in the wild type rats matched each other and demonstrated rapid washout of the tracer from the urinary tract. SPECT images in human breast carcinoma-bearing mice demonstrated a detectable tumor uptake in 48 h post-injection.  相似文献   
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