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BACKGROUND AND OBJECTIVE: To determine the effectiveness of subthreshold (invisible) diode laser (810 nm) modified grid photocoagulation for the treatment of diffuse diabetic macular edema (DDME). METHODS: Fifty eyes of 29 patients were treated with subthreshold (invisible) diode laser modified grid photocoagulation for DDME in a prospective pilot clinical trial. Follow-up was conducted for a minimum of 6 months (average: 14.11 +/- 6.15 months). Re-treatment was performed for residual edema involving the foveal avascular zone. Ten patients were tested with Goldman visual field pre- and post-treatment. Visual improvement, visual loss, visual field, reduction/elimination of macular edema, and the number of treatments per eye were studied. RESULTS: Reduction/elimination of DDME was observed in 39% of the eyes after 1 to 3 treatments (2.22 +/- 0.84 treatments) in 6 to 12 months; and in 74% of eyes after 1 to 5 treatments (2.90 +/- 1.02 treatments) 15-24 months follow-up. The presence of cystoid macular edema, initial poor visual acuity, or a history of systemic hypertension did not affect the outcome. Patients without a history of systemic vascular diseases had a better chance of visual stabilization or improvement. Eighty-eight percent of the patients had at least stable vision at the last follow-up. Two out of 10 visual field tests showed a decrease in paracentral scotomas; no post-treatment subjective complaints of increased paracentral scotomas were encountered. CONCLUSION: Subthreshold (invisible) diode laser modified grid photocoagulation is effective in reducing/eliminating DDME, although resolution of edema may be slightly prolonged. However, this method may be advantageous in that it appears to reduce the objective and subjective effect on the paracentral visual field. Subthreshold (invisible) diode laser modified grid photocoagulation substantially reduces the post-treatment atrophic scarring.  相似文献   
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Familial Mediterranean fever (FMF) is an autosomal-recessive disease. It is characterized by recurring fever, abdominal pain, and serositis. The Mediterranean fever (MEFV) gene is localized on 16p13.3 and more than 35 mutations have been described to date. There are some differences in the gene mutations of FMF in the various ethnic groups. The aim of this study is to determine the frequency of the mutations which has been reported comparatively rare, to define the most effective mutation set, and to select the most suitable DNA analysis system for Turkish FMF patients. Mutations in 330 Turkish FMF patients with typical phenotypes from various regions of Turkey were evaluated for the research purposes. These patients were analyzed for six MEFV gene mutations by the NanoChip® Molecular Genetics Workstation. The most frequent mutation was M694V, identified in 50.00% of the alleles examined; M680I followed with 14.10% and V726A—9.70%. Consequently, we determined that R761H (n?=?23; 3.48%) was the most frequent rare mutations in Turkish FMF patients. Frequency of the rare mutations were R761H (3.48%), E148Q (1.36%), and M694I (1.21%). All of these mutations were in the compound heterozygote state. Our study showed that R761H mutations were higher than it has been reported in literature until now and were mainly associated with M694V. We suggest that mutation R761H should be included in the mutation scanning analysis researches or considered if the patient has M694V/? mutation especially in Turkish FMF patients. Larger serial studies need to be done to investigate the rate and coexistence of these mutations.  相似文献   
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Poly(methyl methacrylate-glycidyl methacrylate) [Poly(MMA-GMA)] cryogels were synthesized using monomers of methylmethacrylic acid and epoxy group bearing GMA via radical cryopolymerization technique. Synthesized cryogels were used for the immobilization of amyloglucosidase to the cryogel surface using epoxy chemistry. Characterizations of the free and immobilized amyloglucosidase were carried out by comparing the optimum and kinetic parameters of enzymes. For this, pH and temperature profiles of free and immobilized preparation were studied and, it was found that, optimum pH of enzyme was not change upon immobilization (pH 5.0), while optimum temperature of the enzyme shifted 10 °C to warmer region after immobilization (optimum temperatures for free and immobilized enzyme were 55 and 65 °C, respectively). Kinetic parameters of free and immobilized enzyme were also investigated and Km values of free and immobilized amyloglucosidase were found to be 2.743 and 0.865 mg/mL, respectively. Vmax of immobilized amyloglucosidase was found to be (0.496 µmol/min) about four times less than that of free enzyme (2.020 µmol/min). Storage and operational stabilities of immobilized amyloglucosidase were also studied and it was showed that immobilized preparation had much more stability than free preparation. In the present work, amyloglucosidase immobilized poly(MMA-GMA) cryogels were used for continuous glucose syrup production from starch for the first time. Efficiency of immobilized enzyme was investigated and released amount of glucose was found to be 2.54 mg/mL at the end of the 5 min of hydrolysis. The results indicate that the epoxy functionalized cryogels offer a good alternative for amyloglucosidase immobilization applications with increased operational and thermal stability, and reusability. Also, these cryogels can be used for immobilization of other industrially valuable enzymes beyond amyloglucosidase.  相似文献   
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Systemic sclerosis (SSc) is a disease characterized by skin and internal organ involvement. There is progressive accumulation of extracellular matrix components in the skin and involved organs. Tissue fibrosis is the prominent reason for mortality, and still, there is no satisfactory treatment. The aim of this study was to evaluate the effects of urotensin-II (U-II) antagonist palosuran in an animal model of scleroderma. We also planned to measure U-II, endothelin-1 (ET-1), and transforming growth factor-β1 (TGF-β1) levels, as well as the association of these levels with dermal thickness. Twenty-four male mice were included in this study and they were divided into three groups—group 1: control group, group 2: fibrosis group, and group 3: fibrosis + palosuran treatment group. Fibrosis + palosuran treatment in group 3 reduced ET-1, U-II, and TGF-β1 levels. In total, the diminished values were statistically significant in the ET-1 and TGF-β1 levels (p?<?0.05). Dermal thickness was higher in the fibrosis group, when compared with the other groups. There was no significant relationship between dermal thickness and ET-1, U-II, or TGF-β1 levels (p?>?0.05). It is believed that U-II is an important mediator in SSc, and its antagonism with palosuran could be a new treatment choice in SSc.  相似文献   
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Pulmonary arterial hypertension (PAH) is a progressive and a life-threatening disease with its high morbidity and mortality ratios. On searching for new shining targets in pathogenesis, we noticed, in our previous studies, urotensin-II (UII) in systemic sclerosis with potent angiogenic and pro-fibrotic features. Owing to the mimicking properties of UII with endothelin-1 (ET1), we attempted to investigate the effect of palosuran in a PAH rat model. Thirty rats were randomly divided into three groups, with each group comprising 10 rats: group 1 (control group) received the vehicle subcutaneously, instead of monocrotaline (MCT) and vehicle; group 2 (MCT group) received subcutaneous MCT and vehicle; and group 3 (MCT + palosuran group) received subcutaneous MCT and palosuran. Serum UII, ET1, transforming growth factor-β1 (TGF-β1) levels, pulmonary arteriolar pathology of different diameter vessels, and cardiac indices were evaluated. The ET1, TGF-β1, and UII levels were significantly diminished in the treatment group, similar to the controls (p?<?0.001). Right ventricular hypertrophy index and mean pulmonary arterial pressure scores were also significantly reduced in the treatment group (p?=?0.001). Finally, in the 50–125-μm diameter arterioles, in contrast to Groups 3 and 1, there was a statistically significant thickness (p?<?0.01) in the arteriolar walls of rats in Group 2. The treatment effect on arteries of more than 125-μm diameters was found to be valuable but not significant. Owing to its healing effect on hemodynamic, histological, and biochemical parameters of MCT-induced PAH, palosuran as an antagonist of UII might be an optional treatment alternative for PAH.  相似文献   
7.
New files (ProTaper Next/HyFlex/OneShape) are made from novel nickel‐titanium (NiTi) alloys/treatments. The purpose of this study was to compare the cyclic fatigue resistance of these new instruments with that of Revo‐S instruments. Four groups of 20 NiTi endodontic instruments were tested in steel canals with a 3 mm radius and a 60° angle of curvature. The cyclic fatigue of the following NiTi instruments with a tip size 25 and 0.06 taper that were manufactured with different alloys was tested: ProTaper Next X2 (M‐Wire), OneShape (conventional NiTi), Revo‐S Shaping Universal (conventional NiTi) and HyFlex 25/0.6 (controlled memory NiTi wire). A one‐way anova and post‐hoc Tukey's test (α = 0.05) revealed that the HyFlex files had the highest fatigue resistance and the Revo‐S had the least fatigue resistance among the groups (P < 0.001).  相似文献   
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ObjectivesThe aim of this age-matched, controlled, prospective clinical study was to investigate frequency and degree of erectile dysfunction (ED) in patients with obstructive sleep apnea syndrome (OSAS) and to evaluate the results of only continuous positive airway pressure (CPAP) therapy on ED in patients with OSAS.ResultsWhen compared to the control group, a decrease in IIEF-5 scores was found in patients with OSAS. However, this decrease was not statistically significant. After 3 months of CPAP usage in patients with mild to moderate and severe degree OSAS, improvement in IIEF-5 scores was statistically significant. Mean value of IIEF-5 score was 16.63±5.91 before CPAP and were improved up to 20.92±6.79 (P=0.001).ConclusionIt is not certainly possible to say that OSAS is clearly associated with ED. However, after 3 months of regular CPAP usage, ED complaints in patients with OSAS might improve positively. Trials with larger series may give more conclusive data.  相似文献   
10.
Functional limitations for the vitamin K cycle, caused either by mutations in gamma-glutamyl carboxylase or vitamin K epoxide reductase genes, result in hereditary deficiency of vitamin K-dependent coagulation factors (VKCFD1 and VKCFD2, respectively). Patients suffering from VKCFD often share several other anatomical irregularities which are not related to haemostasis. Here we report on nine patients, eight of them previously unreported, who presented with VKCFD1. All were examined with special attention to vitamin K-dependent coagulation factors as well as to bone and heart development and to other anatomical signs of embryonal vitamin K deficiency. In total, we detected ten mutations in the gamma-glutamyl carboxylase gene of which seven have not been previously reported. Most interestingly, additional non-bleeding phenotypes were observed in all patients including midfacial hypoplasia, premature osteoporosis, cochlear hearing loss, heart valve defects, pulmonary stenosis, or pseudoxanthoma elasticum-like phenotype. Undercarboxylated matrix Gla protein, osteocalcin, and periostin appear to be responsible for these defects which are also observed in cases of fetal warfarin syndrome.  相似文献   
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