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111.
Mycophenolic acid (MPA; 1,3-dihydro-4-hydroxy-6-methoxy-7-methyl-3-oxo-5-isobenzylfuranyl)-4-methyl-4-hexenoate), the active metabolite of the immunosuppressant prodrug, mycophenolate mofetil, undergoes glucuronidation to its 7-O-glucuronide as a primary route of metabolism. Because differences in glucuronidation may influence the efficacy and/or toxicity of MPA, we investigated the MPA UDP-glucuronosyltransferase (UGT) activities of human liver microsomes (HLMs) and rat liver microsomes with the goal of identifying UGTs responsible for MPA catalysis. HLMs (n = 23) exhibited higher average MPA glucuronidation rates (14.7 versus 6.0 nmol/mg/min, respectively, p < 0.001) and higher apparent affinity for MPA (K(m) = 0.082 mM versus 0.20 mM, p < 0.001) compared with rat liver microsomes. MPA UGT activities were reduced >80% in liver microsomes from Gunn rats. To identify the active enzymes, human and rat UGT1A enzymes were screened for MPA-glucuronidating activity. UGT1A9 was the only human liver-expressed UGT1A enzyme with significant activity and exhibited both high affinity (K(m) = 0.077 mM) and high activity (V(max) = 28 nmol x min(-1) x mg(-1)). Spearman correlation analyses revealed a stronger relationship between HLM MPA UGT activities and 1A9-like content (r(2) = 0.79) relative to 1A1 (r(2) = 0.20), 1A4-like (r(2) = 0.22), and 1A6 (r(2) = 0.41) protein. A different profile was observed for rat with three active liver-expressed UGT1A enzymes: 1A1 (medium affinity/capacity), 1A6 (low affinity/medium capacity), and 1A7 (high affinity/capacity). Our data suggest that UGT1A enzymes are the major contributors to hepatic MPA metabolism in both species, but 1A9 is dominant in human, whereas 1A1 and 1A7 are likely the principal mediators in control rat liver. This information should be useful for interpretation of MPA pharmacokinetic and toxicity data in clinical and animal studies.  相似文献   
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113.
Intraoperative sestamibi scanning in reoperative parathyroidectomy   总被引:2,自引:0,他引:2  
Rossi HL  Ali A  Prinz RA 《Surgery》2000,128(4):744-750
BACKGROUND: Reoperative neck exploration for hyperparathyroidism is often difficult even for experienced surgeons. Recent advances in preoperative and intraoperative localization techniques have improved successful resection rates. This prospective study evaluates the accuracy and clinical utility of intraoperative technetium 99m sestamibi scanning for localizing hyperfunctioning parathyroid tissue in reoperative neck explorations. PATIENTS AND METHODS: Eleven patients underwent reoperative neck exploration for hyperparathyroidism. Two patients had 3 prior neck explorations, 1 had 2 prior neck explorations, and 8 patients had 1 prior neck operation. Preoperative studies included sestamibi scintigraphy and ultrasound in all patients, magnetic resonance imaging in 4, computed tomography scan in 3, parathyroid arteriogram in 1, and selective venous sampling in 1. All patients underwent intraoperative technetium 99m sestamibi scanning and parathyroid hormone assay. RESULTS: Preoperative technetium 99m sestamibi scanning and ultrasound each successfully localized 7 of 11 hyperfunctioning glands (64%). Intraoperative technetium 99m sestamibi scanning correctly localized 10 of 11 hyperfunctioning glands (91%). Intraoperative parathyroid hormone assay confirmed successful excision of hyperfunctioning tissue in all 11 patients. Postoperatively, all 11 patients had low-normal or normal calcium levels. CONCLUSIONS: Intraoperative technetium 99m sestamibi correctly localized 91% of hyperfunctioning glands compared with 64% localization for preoperative technetium 99m sestamibi and preoperative ultrasound. Intraoperative technetium 99m sestamibi scanning and parathyroid hormone monitoring are useful in reoperative neck explorations for hyperparathyroidism.  相似文献   
114.

目的:研究开角型青光眼患者非穿透性深层巩膜切除术后高阶像差的变化。

方法:研究包括20例患者20眼, 其中10例为原发性开角型青光眼, 10例为继发性开角型青光眼。患者术前接受非穿透性深层巩膜切除术,并辅以Tenon囊下注射(0.02% of MMC)。术前及术后1、3mo用i-Trace分析仪测定角膜总高阶像差。每次随访时评估眼压(IOP)、最佳矫正视力(BCVA)和眼泡形态。手术的成功率分为完全成功、相对成功和失败。

结果:术前IOP为24.05±3.07 mmHg,平均用药2.85±0.67次,随访3mo后,IOP为12.30±3.32 mmHg,平均用药0.70±0.98次。随访期间IOP均明显下降(P<0.001)。术后随访1mo,总高阶像差(HOT)均方根(RMS)和总球型像差值明显升高,3mo后下降。术后各时间段三叶肌和全眼昏迷样像差变化无统计学意义。术后1mo HOT RMS及球形角膜均明显增加,3mo随访后明显减少。术后角膜三叶肌变化与术前相比无统计学意义。患者年龄和IOP对HOT和角膜HOT的变化无显著影响。

结论:深度巩膜切除术后1mo内角膜和眼部高阶像差增加,3mo后下降,与术前相比无统计学意义。在3mo随访时,患者的BCVA和等效球镜(SE)与术前相比无统计学差异。  相似文献   

115.
Our patient is a 3‐week‐old female neonate, presented with complaints of low‐grade fever and a congested nose for one day. Eventually, she developed progressive desaturation, hypotension, and poor perfusion due to severe pulmonary hemorrhage. Then, she developed cardiac arrest and was declared dead.  相似文献   
116.
Background:Virtual reality (VR) is an advanced technique used in physical rehabilitation of neurological disorders, however the effects of VR on balance, gait, and motor function in people with Parkinson’s (PD) are still debated. Therefore, the systematic review aimed to determine the role of VR on motor function, balance and gait in PD patients.Methods:A comprehensive search to identify similar randomised controlled trials was conducted targeting 5 databases including Web of Science, PubMed, CINHAL, Cochrane Library, and Physiotherapy Evidence Database. A total of 25 studies were found eligible for this systematic review, and the methodological assessment of the quality rating of the studies was accomplished using the physiotherapy evidence database scale by 2 authors.Results:Out of the 25 included studies, 14 studies reported on balance as the primary outcome, 9 studies were conducted to assess motor function, and 12 assessed gait as the primary outcome. Most studies used the Unified Parkinson disease rating scale UPDRS (part-III) for evaluating motor function and the Berg Balance Scale as primary outcome measure for assessing balance. A total of 24 trials were conducted in clinical settings, and only 1 study was home-based VR trainings. Out of 9 studies on motor function, 6 reported equal improvement of motor function as compared to other groups. In addition, VR groups also revealed superior results in improving static balance among patient with PD.Conclusion:This systemic review found that the use of VR resulted in substantial improvements in balance, gait, and motor skills in patients with PD when compared to traditional physical therapy exercises or in combination with treatments other than physical therapy. Moreover, VR can be used as a supportive method for physical rehabilitation in patients of PD. However, the majority of published studies were of fair and good quality, suggesting a demand for high quality research in this area.  相似文献   
117.
There is conflicting evidence for the association between smoking and dry eye disease (DED). We conducted a meta-analysis to determine the true relationship between smoking and DED. A systematic literature search was performed using electronic databases, including PubMed, Embase and Cochrane Library, till August 2021 to identify observational studies with data on smoking as risk factor of DED. Quality assessment of the included studies was conducted using Joanna Briggs Institute (JBI) critical appraisal checklists. The random-effects model was used to calculate the pooled odds ratio (OR). Heterogeneity was evaluated by Cochrane Q and I2 index; in addition, subgroup, sensitivity, and meta-regression analyses were performed. Publication bias was assessed using funnel plot and Egger’s regression test. A total of 22 studies (4 cohort and 18 cross-sectional studies) with 160,217 subjects met the inclusion criteria and were included in this meta-analysis. There is no statistically significant relationship between current smokers (ORadjusted = 1.14; 95% CI: 0.95–1.36; P = 0.15; I2 = 84%) and former smokers (ORadjusted = 1.06; 95% CI: 0.93–1.20; P = 0.38; I2 = 26.7%) for the risk of DED. The results remained consistent across various subgroups. No risk of publication bias was detected by funnel plot and Eggers’s test (P > 0.05). No source of heterogeneity was observed in the meta-regression analysis. Our meta-analysis suggest current or former smoking may not be involved in the risk of dry eye disease. Further studies to understand the mechanism of interaction between current smokers and formers smokers with DED are recommended.  相似文献   
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119.
Migraine is a neurological disorder characterized by severe headaches, visual aversions, auditory, and olfactory disorders, accompanied by nausea and vomiting. Zolmitriptan (ZMT®) is a potent 5HT1B/1D serotonin receptor agonist frequently used for the treatment of migraine. It has erratic absorption from the gastrointestinal tract (GIT), but its oral bioavailability is low (40–45%) due to the hepatic metabolism. This makes it an ideal candidate for oral fast dissolving formulations. Hence, the current study was undertaken to design and develop oral fast-dissolving films (OFDFs) containing ZMT for migraine treatment. The OFDFs were formulated by the solvent casting method (SCM) using Pullulan (PU) and maltodextrin (MDX) as film-forming agents and propylene glycol (PG) as a plasticizer. The strategy was designed using Box–Behnken experimental design considering the proportion of PU:MDX and percentage of PG as independent variables. The effectiveness of the OFDF’s was measured based on the following responses: drug release at five min, disintegration time (D-time), and tensile strength (TS). The influence of formulation factors, including percent elongation (%E), thickness, water content, moisture absorption, and folding endurance on ZMT-OFDFs, were also studied. The results showed a successful fabrication of stable ZMT-OFDFs, with surface uniformity and amorphous shape of ZMT in fabricated films. The optimized formulation showed a remarkable rapid dissolution, over 90% within the first 5 min, a fast D-time of 18 s, and excellent mechanical characteristics. Improved maximum plasma concentration (C max) and area under the curve (AUC 0–t) in animals (rats) treated with ZMT-OFDFs compared to those treated with an intra-gastric (i-g) suspension of ZMT were also observed. Copolymer OFDFs with ZMT is an exciting proposition with great potential for the treatment of migraine headache. This study offers a promising strategy for developing ZMT-OFDFs using SCM. ZMT-OFDFs showed remarkable rapid dissolution and fast D-time, which might endeavor ZMT-OFDFs as an auspicious alternative approach to improve patient compliance and shorten the onset time of ZMT in migraine treatment.  相似文献   
120.
Recycled rubber waste (RW) is produced at an alarming rate due to the deposition of 1.5 billion scrap tires annually around the globe, which causes serious threats to the environment due to its open land filling issues. This study investigates the potential application of RW in concrete structures for mitigating the alkali–silica reaction (ASR). Various proportions of RW (5%, 10%, 15%, 20%, and 25%) partially replaced the used aggregates. RW was procured from a local rubber recycling unit. Cubes, prisms, and mortar bar specimens were prepared using a mixture design recommended by ASTM C1260 and tested for evaluating the compressive and flexural strengths and expansion in an ASR conducive environment for specimens incorporating RW. It was observed that the compressive and flexural strength decreased for specimens incorporating RW compared to that of the control specimens without RW. For example, an 18% and an 8% decrease in compressive and flexural strengths, respectively, were observed for specimens with 5% of RW by aggregates volume at 28 days. Mortar bar specimens without RW showed an expansion of 0.23% and 0.28% at 14 and 28 days, respectively, indicating the potential ASR reactivity in accordance with ASTM C1260. A decrease in expansion was observed for mixtures incorporating RW. Specimens incorporating 20% of RW by aggregate volume showed expansions of 0.17% at 28 days, within the limit specified by ASTM C1260. Moreover, specimens incorporating RW showed a lower reduction in compressive and flexural strengths under an ASR conducive environment compared to that of the control specimen without RW. Micro-structural analysis also showed significant micro-cracking for specimens without RW due to ASR. However, no surface cracks were observed for specimens incorporating RW. It can be argued that the use of RW in the construction industry assists in reducing the landfill depositing issues with the additional benefit of limiting the ASR expansion.  相似文献   
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