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61.
Norah K. Alsaif Eman M. Al-Sharif Sarah K. Alsaif Ahmed Mousa Abdulrahman M. Al-Muammar 《Saudi medical journal》2020,41(2):168
Objectives:To report the corneal elevation and thickness values for Saudi myopes and to evaluate the differences between these parameters in subgroups of this target population.Methods:Pentacam corneal topographic maps of the right eyes of patients visiting Al-Hokama Eye Clinic, Riyadh, Saudi Arabia, a tertiary eye center between January 2009 and December 2015 were retrospectively analyzed in this cross-sectional study. The patients were grouped into 3 categories based on their spherical readings: mild (-0.25 to -2.75D), moderate (-3.00 to -5.75D), and severe (≥-6.00D). Furthermore, patients with cylindrical readings of ≥-1.00 diopter were categorized as having myopic astigmatism, whereas those with less than -1.00 cylindrical diopter were categorized as having simple myopia.Results:Our sample was comprised of 1,276 patients; 838 (65.7%) had simple myopia and 438 (34.3%) had myopic astigmatism. The values for the whole myopic group were as follows: anterior corneal elevation (AE) at the apex= 2.60±1.48 (standard deviation), thinnest AE= 2.56±1.68, posterior elevation (PE) at the apex= 3.67±3.58, thinnest PE= 4.92±3.81, central pachymetry= 550.09±34.29, apical pachymetry=550.73±34.64, and thinnest pachymetry= 546.30±34.61. All of the measurements, except the apical PE and thinnest PE, were statistically significant across the simple and myopic astigmatism groups (p<0.05). Comparing the mild to moderate myopia groups revealed a significant difference in the apical AE (p=0.037). Moreover, the comparison between the mild and severe myopia groups revealed that the apical PE and the thinnest PE, as well as the central, apical, and thinnest pachymetry values were statistically significantly different (p<0.05).Conclusion:The corneal elevation indices and thicknesses specific to the Saudi myopes were found to be comparable to the international databases in terms of the elevation and thickness in some of the parameters. 相似文献
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63.
Preeclampsia is characterized by increased thromboxane and decreased prostacyclin levels, which predate symptoms, and can explain some of the clinical manifestations of preeclampsia, including hypertension and thrombosis. In this study, we examined DNA methylation of the promoter region of the thromboxane synthase gene (TBXAS1) and the expression of thromboxane synthase in systemic blood vessels of normal pregnant and preeclamptic women. Thromboxane synthase is responsible for the synthesis of thromboxane A(2), a potent vasoconstrictor and activator of platelets. We also examined the effect of experimentally induced DNA hypomethylation on the expression of thromboxane synthase in a neutrophil-like cell line (HL-60 cells) and in cultured vascular smooth muscle and endothelial cells. We found that DNA methylation of the TBXAS1 promoter was decreased and thromboxane synthase expression was increased in omental arteries of preeclamptic women as compared with normal pregnant women. Increased thromboxane synthase expression was observed in vascular smooth muscles cells, endothelial cells, and infiltrating neutrophils. Experimentally induced DNA hypomethylation only increased expression of thromboxane synthase in the neutrophil-like cell line, whereas tumor necrosis factor-α, a neutrophil product, increased its expression in cultured vascular smooth muscle cells. Our study suggests that epigenetic mechanisms and release of tumor necrosis factor-α by infiltrating neutrophils could contribute to the increased expression of thromboxane synthase in maternal systemic blood vessels, contributing to the hypertension and coagulation abnormalities associated with preeclampsia. 相似文献
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65.
P Karagianni SA Polyzos N Kartali I Zografou C Sambanis 《Advances in medical sciences》2013,58(1):38-43
PurposeComparative efficacy of exenatide versus insulin glargine primarily on glucemic control, and secondarily on body mass index (BMI), lipid profile and blood pressure, in type 2 diabetes mellitus (T2DM) patients suboptimally treated with metformin monotherapy.Material/MethodsForty-seven inadequately treated T2DM patients on metformin assigned to exenatide (n=18) or insulin glargine (n=29) for 26 weeks. Glycosylated hemoglobin (HbA1c), serum lipids, BMI, systolic and diastolic blood pressure, and adverse events, including episodes of hypoglycemia and gastrointestinal symptoms, were recorded.ResultsEither treatment had a similar favorable mean reduction in HbA1c. However, more patients in exenatide group achieved HbA1c ≤ 7% at the 26th week compared with insulin glargine group (p=0.036). Insulin glargine group had significantly more episodes of hypoglycemia compared with exenatide group (p=0.039). Gastrointestinal adverse events were non-significantly higher in the exenatide group. A significantly greater BMI reduction was observed in exenatide group, whereas BMI was not altered in insulin glargine group. Total and LDL cholesterol (p=0.012), and triglycerides (p=0.016) significantly decreased, whereas HDL cholesterol increased (p=0.021) in the exenatide group, whereas only total cholesterol decreased in insulin glargine group. Changes in systolic and diastolic blood pressure were insignificant in both groups.ConclusionsExenatide provided similar reduction in HbA1c, but fewer episodes of hypoglycemia, compared with insulin glargine. Exenatide had also a favorable effect on weight loss, although more gastrointestinal adverse events. Exenatide may provide a justified alternative in second line treatment of T2DM, but more trials are required to elucidate its long-term safety and cost-effectiveness. 相似文献
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Acute painful crisis is a common sequela that can cause significant morbidity and negatively impact the quality of life of patients with sickle cell disease (SCD). Plasma levels of several chemokines and cytokines including tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), IL-6, IL-8, monocyte chemoattractant protein 1 (MCP-1), macrophage inflammatory protein 1α (MIP-1α), and interferon γ (IFN-γ) in patients with SCD showed a distinct and statistically significant rise either during painful crisis or at steady state. Plasma levels of various growth factors, including human vascular endothelial growth factor (VEGF), human basic fibroblast growth factor (FGF), and human hepatocyte growth factor (HGF), showed a sustained 2- to 3-fold increase either during painful crisis or at steady state in patients with SCD. Furthermore, plasma levels of the biomarker d-Dimer, a marker of hypercoagulation, showed a 2- to 3-fold increase either during painful crisis or at steady state in patients with SCD as compared to that in healthy participants, suggesting an increased risk of thrombosis. 相似文献
68.
Khattab MA Eslam M Aly MM Shatat M Mousa YI Abd-Aalhalim H Aly H Shaker Y 《Annals of hepatology》2012,11(1):37-46
Background &; aim. Metabolic abnormalities are common in chronic hepatitis C infection (CHC). However, the genotypic differences of these disarrangements in patients infected with CHC genotype 4 (HCV-4) and its association with liver histology and viral loads remain unknown.Material and methods. We consecutively enrolled 183 HCV-4 patients and 106 healthy matched controls; to compare metabolic profiles and assess pattern of association of HCV RNA levels as well as histological factors with the serum lipid profile.Results. HCV-4 infection is associated with higher homeostasis model assessment of insulin resistance (HOMA-IR) index, despite that, a favourable lipid pattern, consisting of an elevation in HDLC and a reduction in serum cholesterol (TC), LDL-C and triglyceride (TG) levels, in comparison with normal matched adults. Significant fibrosis was independently associated with HOMA-IR, portal/periportal inflammation grade, serum cholesterol and age. Univariate association was elucidated between lower LDL-C and TC and Metavir activity score and between higher TG and TC and steatosis. In multivariate analysis, severe hepatitis activity, milder hepatic fibrosis, and triglyceride levels are associated with higher HCV RNA levels.Conclusion. HCV-4 is associated with wide metabolic changes. A proportional relationship is found between serum lipid profiles and hepatitis C viral load and liver histology in patients with HCV-4. 相似文献
69.
70.
J. Butterworth Trent Cross William Butterworth Paul Mousa S. Thomas 《International journal of surgery case reports》2013,4(7):568-570
INTRODUCTIONTransmesenteric herniae are a rare cause of bowel ischaemia in adults with few reported cases in published literature.PRESENTATION OF CASEWe report a rare case of a 26-year-old female with spontaneous transmesenteric hernia of jejunum and proximal ileum due to a congenital mesenteric defect resulting in bowel gangrene, presenting initially with no haemodynamic or biochemical abnormalities. The hernia was reduced, small bowel resected and primary side to side anastomosis performed, following which the patient made a good recovery and was discharged 5 days later.DISCUSSIONThe insidious onset of transmesenteric herniae and lack of specific radiological or laboratory investigations reaffirms the importance of surgeons maintaining a high index of suspicion for this critical surgical emergency.CONCLUSIONClose monitoring of the patient's general condition in cases of non-specific abdominal pain is essential to identify the rare deteriorating patient for early surgical intervention and optimal outcome. 相似文献