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731.
AIMS: The objective of the present investigation was to examine the relationship of three polymorphisms, Thr394Thr, Gly482Ser and +A2962G, of the peroxisome proliferator activated receptor-gamma co-activator-1 alpha (PGC-1alpha) gene with Type 2 diabetes in Asian Indians. METHODS: The study group comprised 515 Type 2 diabetic and 882 normal glucose tolerant subjects chosen from the Chennai Urban Rural Epidemiology Study, an ongoing population-based study in southern India. The three polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Haplotype frequencies were estimated using an expectation-maximization (EM) algorithm. Linkage disequilibrium was estimated from the estimates of haplotypic frequencies. RESULTS: The three polymorphisms studied were not in linkage disequilibrium. With respect to the Thr394Thr polymorphism, 20% of the Type 2 diabetic patients (103/515) had the GA genotype compared with 12% of the normal glucose tolerance (NGT) subjects (108/882) (P = 0.0004). The frequency of the A allele was also higher in Type 2 diabetic subjects (0.11) compared with NGT subjects (0.07) (P = 0.002). Regression analysis revealed the odds ratio for Type 2 diabetes for the susceptible genotype (XA) to be 1.683 (95% confidence intervals: 1.264-2.241, P = 0.0004). Age adjusted glycated haemoglobin (P = 0.003), serum cholesterol (P = 0.001) and low-density lipoprotein (LDL) cholesterol (P = 0.001) levels and systolic blood pressure (P = 0.001) were higher in the NGT subjects with the XA genotype compared with GG genotype. There were no differences in genotype or allelic distribution between the Type 2 diabetic and NGT subjects with respect to the Gly482Ser and +A2962G polymorphisms. CONCLUSIONS: The A allele of Thr394Thr (G --> A) polymorphism of the PGC-1 gene is associated with Type 2 diabetes in Asian Indian subjects and the XA genotype confers 1.6 times higher risk for Type 2 diabetes compared with the GG genotype in this population.  相似文献   
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The novel coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2, has challenged the medical community. Several ocular manifestations secondary to COVID-19 have been documented. Prolonged hospitalization exposes the patient to various multiresistant bacteria making them prone to various secondary infections. This case series describes four cases of presumed fungal endogenous endophthalmitis in patients who recovered from COVID-19.  相似文献   
735.
Endovascular repair of abdominal aortic aneurysm is a common procedure and not without complications. The aim of this study was to evaluate the early results of the Anaconda endograft (Vascutek Ltd., Inchinnan, Scotland, UK) in 106 patients in three hospitals in the west of Scotland. A prospective registry of 106 consecutive patients undergoing endoluminal repair of their abdominal aortic aneurysms using the Anaconda device was set up to record the clinical outcomes, with a mean follow-up of two years. There was no 30-day perioperative mortality in the 106 patients. Only type II endoleaks were detected on serial computed tomography scanning at follow-up. Technical success was achieved in 99% (105/106) in this study; one patient was converted to open surgical repair. Two cases of proximal device migration (>1 cm) were detected at one month and 19 months, respectively, with no associated endoleak or sac enlargement. Five cases of endograft limb thrombosis were noted in this study. Our early clinical experience with the Anaconda endograft compares favourably with other commercially available endografts in the treatment of abdominal aortic aneurysms. The main advantages of this device are that it is re-deployable and that it has a magnetic wire system which makes it easy to implant.  相似文献   
736.
Edited MRS sequences are widely used for studying γ-aminobutyric acid (GABA) in the human brain. Several algorithms are available for modelling these data, deriving metabolite concentration estimates through peak fitting or a linear combination of basis spectra. The present study compares seven such algorithms, using data obtained in a large multisite study. GABA-edited (GABA+, TE = 68 ms MEGA-PRESS) data from 222 subjects at 20 sites were processed via a standardised pipeline, before modelling with FSL-MRS, Gannet, AMARES, QUEST, LCModel, Osprey and Tarquin, using standardised vendor-specific basis sets (for GE, Philips and Siemens) where appropriate. After referencing metabolite estimates (to water or creatine), systematic differences in scale were observed between datasets acquired on different vendors' hardware, presenting across algorithms. Scale differences across algorithms were also observed. Using the correlation between metabolite estimates and voxel tissue fraction as a benchmark, most algorithms were found to be similarly effective in detecting differences in GABA+. An interclass correlation across all algorithms showed single-rater consistency for GABA+ estimates of around 0.38, indicating moderate agreement. Upon inclusion of a basis set component explicitly modelling the macromolecule signal underlying the observed 3.0 ppm GABA peaks, single-rater consistency improved to 0.44. Correlation between discrete pairs of algorithms varied, and was concerningly weak in some cases. Our findings highlight the need for consensus on appropriate modelling parameters across different algorithms, and for detailed reporting of the parameters adopted in individual studies to ensure reproducibility and meaningful comparison of outcomes between different studies.  相似文献   
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Purpose: To retrospectively analyze clinical features, laboratory investigations, treatment and visual outcomes in patients with tubercular subretinal abscess.

Methods: A total of 12 eyes of 12 patients receiving a diagnosis of subretinal abscess, between 2004 and 2014, were included for this retrospective study.

Results: The mean age of the presentation was 29.75 ± 16.72 years (range: 14–62 years) and seven (58.3%) were male. The most common anterior segment presentation was anterior uveitis (75%). The mean BCVA at presentation was 1.62 (in logMAR). A tuberculin skin test was positive in seven patients (58.3%) and five patients had a history of pulmonary tuberculosis. Polymerase chain reaction for the Mycobacterium tuberculosis genome was positive in 6 of 11 eyes from aqueous aspirate (54%) and 4 of 7 eyes from vitreous aspirates (57.14%). All patients were started on systemic steroids and an anti-tubercular regimen. The mean duration of follow-up was 134.28 days. The mean BCVA at final presentation was 1.19 (in logMAR). Chorioretinal scar was the most common finding after resolution.

Conclusions: Subretinal abscess is a rare manifestation of ocular tuberculosis. A high degree of suspicion and timely management of the condition can prevent loss of vision.  相似文献   

739.
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