Biomedical subjects

Sami T Azar

Publications and source records attributed to Sami T Azar.

11 recordsLinked to original sources

PubMed2006

Intravenous zoledronic acid treatment in thalassemia-induced osteoporosis: results of a phase II clinical trial.

Osteoporosis is an important cause of morbidity in beta-thalassemia patients. Bisphosphonates have been recently used for the treatment of osteoporosis in beta-thalassemia. This study is a prospective quasi-experimental study to assess the efficacy and safety of zoledronic acid in thalassemics with osteoporosis. Eighteen thalassemia patients with osteoporosis were given zoledronic acid 4 mg intravenously every 3 months over a period of 12 months. The efficacy of treatment was assessed by measuring (BMD) at the lumbar spine, femoral neck, and hip at baseline, 6, and 12 months. Z-score was used to measure the BMD. Other medical assessments included markers of bone formation and resorption (bone alkaline phosphatase (BAP), osteocalcin (OC), and urinary deoxypyridinoline), and the assessment of pain score, analgesic score, and performance score. Ten thalassemic osteoporotic patients were followed up only with serial BMDs as controls. Both groups had no significant difference with respect to age, gender, and baseline BMD. Patients taking zoledronic acid had a significant increase in their lumbar spine, femoral neck, trochanter, and total hip BMD measurements over the 12-month period. Patients in the control group did not have any significant change in BMD measurements. There was a significant change in the levels of OC and BAP over the 12-month follow-up period. There was also a significant decrease in the number of painful sites experienced by the patients. Treatment of thalassemic osteoporotic patients with zoledronic acid is very effective in increasing BMD at the lumbar spine and hip and in reducing pain; it is also well-tolerated.

Adolescent↗

PubMed2006

Impact of seafood and fruit consumption on bone mineral density.

OBJECTIVES: Over the past decade, dietary choices and nutrition have proven to be major modulators of bone mineral density (BMD) in men and women. We investigated environmental determinants, specifically dietary habits, of BMD by using multiple regression models in a rural Chinese population. METHODS: BMDs were measured at the hip and total body in 5848 men and 6207 women, aged 25-64. Dietary and supplemental intakes were assessed by a simple, one-page questionnaire tailored to collect nutritional information from large rural populations. Another questionnaire was used to collect information on the subjects' age, disease history, smoking, alcohol consumption, physical activity as well as women's menstrual status and reproductive history. Multiple regression models were used to assess the relationships among dietary variables and BMD, after adjusting for age, BMI (body mass index), weight, occupation, smoking status, and alcohol consumption. RESULTS: Increasing seafood consumption was significantly associated with greater BMD in women (p<0.001), especially those consuming more than 250 g per week of seafood. One thousand and three hundred and twenty-four men and 1479 women consumed >250 g of fruit per week. Higher fruit intake was found to be significantly associated with higher BMD in both sexes (p<0.05). High vegetable consumption, however, did not positively impact BMD. CONCLUSIONS: This study with its large population size has identified preventive measures, as well as some risk factors, involved in bone loss and osteoporosis. Our results highlight the importance of several dietary variables as significant determinants of BMD. It also emphasizes the role of dietary intake in general and shows that specific foods, such as fruits and seafood, can positively impact BMD.

Absorptiometry, Photon↗

PubMed2006

Variations in postprandial ghrelin status following ingestion of high-carbohydrate, high-fat, and high-protein meals in males.

AIM: The purpose of this study was to investigate the response of postprandial acylated ghrelin to changes in macronutrient composition of meals in healthy adult males. METHODS: A randomized crossover study was performed. Ten healthy adult males were recruited. All subjects received, on separate occasions, a high-carbohydrate (HC), a high-fat (HF), and a high-protein (HP) meal. Blood samples were collected before and 15, 30, 60, 120, and 180 min following the ingestion of each meal. Plasma acylated ghrelin as well as serum insulin, glucose, and triglycerides were measured. RESULTS: The levels of acylated ghrelin fell significantly following the three meals. The HC meal induced the most significant decrease in postprandial ghrelin secretion (-15.5 +/- 2.53 pg/ml) as compared with HF (-8.4 +/- 2.17 pg/ml) and HP (-10.0 +/- 1.79 pg/ml) meals (p < 0.05). However, at 180 min, the HP meal maintained significantly lower mean ghrelin levels (29.7 +/- 3.56 pg/ml) than both HC (58.4 +/- 5.75 pg/ml) and HF (45.7 +/- 5.89 pg/ml) meals and lower levels than baseline (43.4 +/- 5.34 pg/ml) (p <0.01). The postprandial insulin levels increased to significantly higher levels following the HC meal (+80.6 +/- 11.14 microU/ml) than following both HF (37.3 +/- 4.82 microU/ml) and HP (51.4 +/- 6.00 microU/ml) meals (p < 0.001). However, at 180 min, the mean insulin levels were found to be significantly higher following the HP meal (56.4 +/- 10.80 microU/ml) as compared with both HC (30.9 +/- 4.31 microU/ml) and HF (33.7 +/- 4.42 microU/ml) meals (p < 0.05). Acylated ghrelin was also found to be negatively correlated with circulating insulin levels, across all meals. CONCLUSIONS: These results indicate that the nutrient composition of meals affects the extent of suppression of postprandial ghrelin levels and that partial substitution of dietary protein for carbohydrate or fat may promote longer-term postprandial ghrelin suppression and satiety. Our results also support the possible role of insulin in meal-induced ghrelin suppression.

Adult↗

PubMed2005

Predictors of coronary artery disease in the Lebanese population.

BACKGROUND: Coronary artery disease (CAD) is one of the major causes of morbidity and mortality in the world. The disease is determined by many risk factors such as age, gender, diabetes, dyslipidemia, smoking, as well as elevated serum levels of lipoprotein (a) (Lp(a)), homocysteine, C-reactive protein (CRP) and uric acid. In this study, we evaluated the association of biologic and metabolic parameters with CAD in a group of Lebanese patients. METHODS: Three hundred patients were recruited for the study. Biologic and blood metabolic parameters were measured. Patients were then divided into 3 groups according to their catheterization result: 0% stenosis (controls), <50% stenosis and >or=50% stenosis. RESULTS: Hyperlipidemias, CRP, homocysteine and uric acid levels in CAD patients were not different from those of the controls. However, age, elevated fasting blood glucose (FBG) and elevated serum Lp(a) levels were found to be strong independent predictors of CAD in our study population. Association with CAD was also shown for gender, hypertension, diabetes and family history of CAD. CONCLUSION: We report the importance of serum Lp(a) levels and FBG in the prediction and prevention of CAD in our population.

Aged↗

PubMed2005

Hypertriglyceridemia and peripheral neuropathy in neurologically asymptomatic patients.

OBJECTIVES: In this study we intended to find a correlation between hypertriglyceridemia and peripheral neuropathy (PN) in patients with a high triglyceride level and no neurological complaints. METHODS: We recruited 24 patients (21 males and 3 females) having a triglyceride level above 300 mg/dl with no neurologic complaints and none of the other common causes of PN and they underwent an electroneurographic study. The distal motor or sensory latencies (DL), motor or sensory conduction velocities (CV), and motor or sensory amplitudes (AMP) were collected for the peroneal, posterior tibial, sural, median, and ulnar nerves and were considered abnormal if they fall above or below 2 standard deviations of reference values. RESULTS: Our results show that 70.8% of the patients had a significant delay in the DL of the sural nerves and 66.7% had a significant delay in the DL of the median sensory fibers. 54.2% of the patients had a significant decrease in the motor CV in the posterior tibial nerves and 33.3% had a significant decrease in the sensory CV in the sural nerves. The means of the DL and CV were significantly different from reference values in most of the nerves. Amplitudes were the least if at all affected. CONCLUSION: The pattern of the abnormalities affecting more the DL, the sensory nerves and the longer nerves of the lower extremities is suggestive of an early axonal polyneuropathy. We conclude that hypertriglyceridemia affects conduction parameters in peripheral nerves in a trend suggestive of early peripheral neuropathy.

Adult↗

PubMed2004

Patients with early onset of type 1 diabetes have significantly higher GG genotype at position 49 of the CTLA4 gene.

Type 1 diabetes (T1D) is a complex autoimmune disease. Several genetic loci have been implicated in the susceptibility to this illness. Evaluated was the role of the CTLA4 exon 1 A49G polymorphism and its role as a risk factor for T1D in our population. DNA from 190 patients with T1D and their families and 96 control individuals were genotyped for CTLA4 exon 1 polymorphism and human leukocyte antigen (HLA)-DQB1*0201 and *0302 haplotypes by polymerase chain reaction (PCR) amplification-restriction enzyme analysis and PCR amplification that used sequence-specific primers, respectively. Patients were nonobese and <26 years old. The CTLA4 G allele was found to be more frequently present in patients with T1D (32.4%) as compared with its frequency in control individuals (24.5%). The GG genotype was also significantly higher among patients (12.6%) than in controls (4.2%). chi(2) analysis and family-based association studies were performed and suggested the association of CTLA4 exon 1 G polymorphism with T1D (p = 0.0229). Furthermore, in HLA-DQB1*0201-positive patients with T1D, the GG and AA genotypes were higher and lower, respectively, than those found in control individuals. This study suggests that CTLA4 is a candidate susceptibility gene for T1D.

Adolescent↗

PubMed2003

No association between the -1031 polymorphism in the TNF-alpha promoter region and type 1 diabetes.

Tumor necrosis factor alpha (TNF-alpha) is an important immunomodulator and is believed to be involved in the development or progression of type 1 diabetes. In the following study, we evaluated TNF-alpha promoter polymorphisms at positions -863 and -1031 and their association with type 1 diabetes in a group of 210 diabetic patients from Lebanon. Our results show that in our population, the C allele is predominant at position -863, whereas the A allele is very rare (2%). At position -1031, however, the C and T allele distribution was similar in both the patient (17.8% vs 82.2%, respectively) and the control (21.4% vs 79.6%) groups. No association of TNF-alpha genotype at position 1031 with type 1 diabetes was found as demonstrated by the family-based association test and the transmission disequilibrium test. However, when patient genotypes were compared, the recessive CC genotype was only found in type 1 diabetic males but not in type 1 diabetic females. This observation, however, requires further investigation in a larger sample before conclusive association to gender is suggested. In conclusion, our results demonstrate that no association between TNF-alpha polymorphism and type 1 diabetes seems to exist in our population.

Adolescent↗

PubMed2003

Endocrine changes in a rat model of chronic hypoxia mimicking cyanotic heart disease.

OBJECTIVE: The endocrine system plays an important role in the adaptation to hypoxia. The aim of this study is to assess the effect of chronic hypoxia on endocrine changes in a neonatal animal model mimicking cyanotic heart disease. METHODS: Sprague-Dawley rats were placed in a normobaric hypoxic environment at birth and oxygen levels were maintained at 10% in an airtight Plexiglas chamber. Controls remained in room air. Animals were sacrificed at 4 and 8 weeks of life. Hematocrit, Free T4 (FT4), Thyrotropin (TSH), corticosterone, and Growth hormone (GH) were measured. RESULTS: Significant polycythemia developed in the hypoxic rats. Free T4 levels were significantly lower in the hypoxic (H) group compared to the control (C) group at 4 and 8 weeks with FT4 of 2.44 +/- 1.11 ng/dL (H) and 4.35 +/- 1.62 (C) at 4 weeks with a p value < 0.005 and FT4 of 2.01 +/- 0.36 (H) and 3.25 +/- 0.54 (C) ng/dL at 8 weeks with p < 0.01. At 8 weeks TSH levels were significantly lower in the hypoxic group (1.84 +/- 0.9 ng/mL (H) vs. 3.11 +/- 1.1 (C)) with p < 0.05. Corticosterone levels were higher in the hypoxic group with values of 126 +/- 14.8 ng/mL (H) and 114.1 +/- 12.6 (H) at 4 and 8 weeks respectively, when compared to the control group with values of 82.9 +/- 18.1 (C) and 92.7 +/- 10.3 (C) and 4 and 8 weeks with p < 0.0005 and < 0.05 respectively. Growth hormone levels were lower in the hypoxic group at 4 and 8 weeks with p < 0.05 and p < 0.001, respectively. CONCLUSION: Chronic hypoxia in our neonatal rat model was associated with decrease in growth hormone levels and an increase in corticosterone levels. Furthermore, hypoxia resulted in thyroid hormone axis suppression. This effect seems to centrally mediated.

Adaptation, Physiological↗

PubMed2002

Higher serum leptin level in women than in men with type 1 diabetes.

Leptin is the protein product of the obese (ob) gene, a lipostatic hormone that contributes to body weight regulation through suppressing appetite and/or stimulating energy expenditure in humans and/or rodents. In humans, serum leptin concentrations are increased in relation to increased body fat content. Studies have shown a higher leptin level in women compared with men. However, the gender influence on serum leptin concentrations has never been evaluated in patients with type 1 diabetes. In this study, serum leptin levels and percentage body fat mass were measured in men and women with type 1 diabetes. Fasting serum leptin levels were higher in women (16.7 + 11.6 ng/mL) than in men (3.0 +/- 1.5 ng/mL; P < 0.05) and were independent of exogenous insulin intake and of glucose control. Percentage body fat and fat mass were significant determinants of leptin concentration, whereas age and duration of diabetes were not related to leptin concentration. Subgroups of men (n = 12) and women (n = 11) with total body fat between 20 and 30% were compared. Leptin levels were also higher in women compared with men (13.5 +/- 8.3 ng/mL versus 3.2 +/- 1.7 ng/mL; P < 0.05, respectively). In conclusion, our findings indicate that gender is an important determinant of serum leptin concentration in type 1 diabetics, this gender difference is partly explained by body fat distribution and that type 1 diabetic women may be more resistant than type 1 diabetic men to leptin's alleged lipostatic actions.

Adipose Tissue↗

PubMedDate not supplied

Silent pituitary infarction after coronary artery bypass grafting procedure: case report and review of literature.

OBJECTIVE: To report a case of silent pituitary infarction that occurred after a coronary artery bypass grafting procedure and review the relevant literature. METHODS: We describe a female patient with silent pituitary infarction several months after a coronary artery bypass operation and discuss her presentation, clinical findings, and laboratory evaluation. We also review similar cases in the literature. RESULTS: A 73-year-old woman presented with generalized fatigue, weakness, and an elevated creatine kinase level several months after she had undergone a coronary artery bypass procedure. The findings on laboratory evaluation were consistent with hypogonadism, growth hormone deficiency, central hypothyroidism, and adrenal insufficiency. Magnetic resonance imaging of the pituitary fossa showed an empty sella turcica and no sellar enlargement. The patient had no headaches, no neuro-ophthalmologic symptoms, and no focal neurologic deficits. The presentation was slow and insidious. The patient received glucocorticoid and thyroid hormone replacement therapy, after which her clinical status improved substantially. Silent pituitary infarction after coronary artery bypass grafting has been reported previously in 3 male patients, but our current case is the first such report in a female patient. CONCLUSION: Silent pituitary infarction can be a complication of a coronary artery bypass grafting procedure, with a delayed and insidious presentation.

Aged↗

PubMedDate not supplied

Erectile dysfunction in diabetic patients.

Erectile dysfunction (ED) appears to be highly prevalent in diabetic patients (around 50% at 50 years of age) and more severe than in the rest of the population. Its etiology is multifactorial in this subset of patients. ED is highly correlated to multiple vascular risk factors and can be considered as a manifestation of endothelial dysfunction in general, alerting the physician to look at underlying silent coronary bed atherosclerosis. It is also dependent on the poor control of diabetes and on the presence of its chronic complications. Because of the multiple etiologies of ED in diabetics, a multifactorial approach is warranted to get an optimal response in treating such patients: diabetes control, use of phosphodiesterase 5 inhibitors, psychosexual counseling, and choice of antihypertensive medications.

Diabetic Angiopathies↗