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171.
Birt-Hogg-Dube (BHD) is a tumor suppressor gene disorder characterized by skin hamartomas, cystic lung disease, and renal cell carcinoma. The fact that hamartomas, lung cysts, and renal cell carcinoma can also occur in tuberous sclerosis complex (TSC) suggests that the BHD and TSC proteins may function within a common pathway. To evaluate this hypothesis, we deleted the BHD homolog in Schizosaccharomyces pombe. Expression profiling revealed that six permease and transporter genes, known to be down-regulated in Deltatsc1 and Deltatsc2, were up-regulated in Deltabhd, and levels of specific intracellular amino acids known to be low in Deltatsc1 and Deltatsc2 were elevated in Deltabhd. This "opposite" profile was unexpected, given the overlapping clinical phenotypes. The TSC1/2 proteins inhibit Rheb in mammals, and Tsc1/Tsc2 inhibit Rhb1 in S. pombe. Expression of a hypomorphic allele of rhb1(+) dramatically increased permease expression levels in Deltabhd but not in wild-type yeast. Loss of Bhd sensitized yeast to rapamycin-induced increases in permease expression levels, and rapamycin induced lethality in Deltabhd yeast expressing the hypomorphic Rhb1 allele. In S. pombe, it is known that Rhb1 binds Tor2, and Tor2 inhibition leads to up-regulation of permeases including those that are regulated by Bhd. Our data, therefore, suggest that Bhd activates Tor2. If the mammalian BHD protein, folliculin, similarly activates mammalian target of rapamycin, it will be of great interest to determine how mammalian target of rapamycin inhibition in BHD patients and mammalian target of rapamycin activation in TSC patients lead to overlapping clinical phenotypes.  相似文献   
172.
The study of conserved protein interaction networks seeks to better understand the evolution and regulation of protein interactions. Here, we present a quantitative proteomic analysis of 18 orthologous baits from three distinct chromatin‐remodeling complexes in Saccharomyces cerevisiae and Homo sapiens. We demonstrate that abundance levels of orthologous proteins correlate strongly between the two organisms and both networks have highly similar topologies. We therefore used the protein abundances in one species to cross‐predict missing protein abundance levels in the other species. Lastly, we identified a novel conserved low‐abundance subnetwork further demonstrating the value of quantitative analysis of networks.  相似文献   
173.
Elongation of very long-chain fatty acids (ELOVL) members were overexpressed in two preadipocyte cell lines, ELOVL2 and ELOVL3 in 3T3-L1 cells, and ELOVL1-3 in F442A cells. Cells overexpressing ELOVL2, whose preferred substrates are arachidonic acid (AA, C20:4n-6) and eicosapentaenoic acid (EPA, C20:5n-3), showed an enhanced triacylglycerol (TAG) synthesis and subsequent accumulation of lipid droplets. Incorporation of fatty acid (FA) but not of glucose into TAG was enhanced by ELOVL2-overexpression. Two lipogenic genes encoding diacylglycerol acyltransferase-2 (DGAT2) and fatty acid-binding protein-4 (FABP4, aP2) were induced in ELOVL2-overexpressing cells, whereas no such effect was seen on the fatty acid synthase (FAS) gene.  相似文献   
174.
Preemptive analgesia aims to prevent the sensitization of central nervous system, hence the development of pathologic pain after tissular injury. The aim of the study was to assess the effect of preincisional clonidine treatment on analgesic consumption and hemodynamic stability compared to clonidine administered at the end of the operation and control group. Ninety-one patients undergoing elective colorectal surgery were randomly assigned to four groups: peroral clonidine before operation, epidural clonidine before operation, epidural clonidine at the end of operation, and epidural saline before operation as a control group. After the operation, patient-controlled analgesia with epidural morphine was instituted. Analgesic consumption, blood pressure and heart rate were obtained at 1, 2, 6 and 24 h postoperatively, and the cumulative consumption of analgesics was assessed at the end of the study period. Significant differences (p < 0.05) in postoperative systolic blood pressure, with highest hemodynamic stability was observed at 1 h and 6 h in the group of patients administered epidural clonidine before operation. In this group of patients we found significant reduction in analgesic consumption during the study period (p < 0.05), compared to other groups. The cumulative consumption of analgesics assessed at the end of the study period was significantly reduced (p < 0.05) in the group of patients administered epidural clonidine before operation (8.40 +/- 3.74, respectively) as compared with the peroral clonidine before operation (16.79 +/- 5.75, respectively), epidural clonidine at the end of the operation (11.11 +/- 4.24, respectively) and control group of patients (18.00 +/- 6.45, respectively). Preincisional administration of epidural clonidine was associated with a significantly lower analgesic use, lower cumulative analgesic consumption and greater hemodynamic stability, in comparison with other groups.  相似文献   
175.
Blue light can damage retina and cause age related macular degeneration. After cataract surgery and lens removal retina stays unprotected. Blue light filtering intraocular lenses (IOL) increase protection of the retina. In our prospective study we investigated clinical results after bilateral implantation of Acrysof Natural IOL to 30 patients (N = 60 eyes). In a control group (N = 60 eyes, 30 patients), standard acrysof IOL was implanted bilaterally. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA) and Nd YAG laser capsulotomy rate were measured and compared with control group. Subjective patient's satisfaction and subjective colour perception were also investigated. There was no significant difference in UCVA, BCVA and Nd YAG laser capsulotomy rate between the two groups. High patient's satisfaction was noticed (96.7% of patients would implant Acrysof Natural IOL again). Acrysof Natural IOL enables good visual acuity VA, low rate of Nd YAG laser capsulotomy and high patient's satisfaction without colour perception disturbances.  相似文献   
176.
To evaluate photodynamic therapy with verteporfin combined with intravitreal bevacizumab in minimally classic and occult choroidal neovascularization secondary to age-related macular degeneration. 46 eyes of 46 patients (mean age 74.5) included in this prospective, noncomparative, interventional case series. Median follow-up was 24 weeks (12-36). Verteporfin photodynamic therapy (PDT) was followed by 0.05 mL (1.25 mg) of bevacizumab injected intravitreally within 24 hours and again after 6 weeks. Whole procedure was repeated in 3-month intervals in case of leakage. Visual acuity (VA) improved in majority of patients (baseline VA 1.041 log MAR) by mean increase of 1.45 lines (last follow-up) (p = 0.001). Central foveal thickness (CFT) and total macular volume (TMV) decreased by 53 microm (p = 0.03) and 1.04 mm3 (p < 0.001) respectively. No serious complications were observed. Combined treatment may improve outcome of monotherapy. Significant improvement in VA, CFT and TMA was noted in majority of patients and maintained during follow-up.  相似文献   
177.
Gait pattern is a frequent problem in cerebral palsy. The aim of the investigation is the evaluation of proximal femur normalization and/or pelvis normalization after surgical correction and simultaneous operations on soft tissues of lower limbs, as well as walk analysis. From 1980. to 2000. were operated 856 patients, 476 male and 380 female, between 1-51 years. Basic walk parameters were analyzed: step length, speed and the number of steps in one minute (cadence). 75.25% of patients had good results with improved of centrum collum diaphysis (CCD) and angle of anteversion (AV) or antetorsion (AT) for 70%, and more independent walking with contracture corrections and decreased spasticism. The best results were achieved with simultaneous two-side operations, with patients' age between 1 and 3, achieving independent walking. More operations at the same time significantly reduce spasticism--one anesthesia, one immobilization, and later same time post-operative physical therapy and satisfactory better results.  相似文献   
178.
Female athletes participating in high-risk sports suffer anterior cruciate ligament (ACL) knee injury at a 4- to 6-fold greater rate than do male athletes. ACL injuries result either from contact mechanisms or from certain unexplained non-contact mechanisms occurring during daily professional sports activities. The occurrence of non-contact injuries points to the existence of certain factors intrinsic to the knee that can lead to ACL rupture. When knee joint movement overcomes the static and the dynamic constraint systems, non-contact ACL injury may occur. Certain recent results suggest that balance and neuromuscular control play a central role in knee joint stability, protection and prevention of ACL injuries. The purpose of this study is to evaluate balance neuromuscular skills in healthy Croatian female athletes by measuring their balance index score, as well as to estimate a possible correlation between their balance index score and balance effectiveness. This study is conducted in an effort to reduce the risk of future injuries and thus prevent female athletes from withdrawing from sports prematurely. We analysed fifty-two female athletes in the high-risk sports of handball and volleyball, measuring for their static and dynamic balance index scores, using the Sport KAT 2000 testing system. This method may be used to monitor balance and coordination systems and may help to develop simpler measurements of neuromuscular control, which can be used to estimate risk predictors in athletes who withdraw from sports due to lower sports results or ruptured anterior cruciate ligament and to direct female athletes to more effective, targeted preventive interventions. The tested Croatian female athletes with lower sports results and ACL knee injury incurred after the testing were found to have a higher balance index score compared to healthy athletes. We therefore suggest that a higher balance index score can be used as an effective risk predictor for lower sports results and lesser sports motivation, anterior cruciate ligament injury and the ultimate decision to withdraw from active participation in sports. If the balance testing results prove to be effective in predicting the occurrence of ligament injuries during future sports activities, we suggest that prophylactic training programs be introduced during athlete training, since the prevention of an initial injury will be more effective than prevention of injury recurrence.  相似文献   
179.
Trigonopsis variabilis D-amino acid oxidase accounts for 35% of Escherichia coli protein when added D-methionine suppresses the toxic activity of the recombinant product. Permeabilized E. coli cells are reusable and stabilized enzyme preparations. The purified oxidase lacks the microheterogeneity of the natural enzyme. Oriented immobilization of a chimeric oxidase maintains 80% of the original activity in microparticle-bound enzymes.  相似文献   
180.
The recB268::Tn10 mutation was introduced into the HfrH strain of Escherichia coli. Compared with recB F and recB F+ cells, the viability of this mutant strain was much lower. Compared with wild-type HfrH, the recB derivative donated much shorter fragments of its chromosome to the recipient. It is suggested that the recB gene product (i.e., RecBCD enzyme) participates in Hfr transfer.  相似文献   
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