Prevalence and risk factors of retinal vein occlusion: the Gutenberg Health Study.

OBJECTIVE: To determine the age- and sex-specific prevalence and determinants of retinal vein occlusions (RVOs) in a large population-based German cohort. METHODS: The investigation included 15,010 participants (aged 35-74 years) from the Gutenberg Health Study. We determined the prevalence of RVO (central retinal vein occlusion [CRVO] and branch retinal vein occlusion [BRVO]) for the local population by assessing fundus photographs of 12 954 (86.3%; 49.8% women and 50.2% men) participants. Further, we analyzed the associations of RVO with cardiovascular, anthropometric, and ophthalmic parameters. RESULTS: The weighted prevalences of RVO, CRVO, and BRVO were 0.40%, 0.08%, and 0.32%, respectively. Men were 1.7 times more frequently affected by RVO than were women. Prevalence of RVO was 0.2% in participants aged 35-44 and 45-54 years, respectively, 0.48% in those aged 55-64 years, and 0.92% in those aged 65-74 years. Of persons with RVO, 91.5% had one or more cardiovascular risk factor or disease vs. 75.9% of persons without RVO. BRVO was associated with arterial hypertension (odds ratio 2.69, 95% confidence interval 1.27-5.70) and atrial fibrillation (3.37, 1.24-9.12) and CRVO with higher age (7.02, 1.63-30.19) and a family history of stroke (4.64, 1.18-18.25). Median visual acuity (base 10 logarithm of minimum angle of resolution) was 0.2 in persons with RVO vs. 0.05 in those without. CONCLUSION: The prevalence of RVO in this German population was 0.4%, and men were 1.7 times more frequently affected than women. CRVO was associated with higher age and a family history of stroke, and BRVO was associated with arterial hypertension and atrial fibrillation.

Real-time analysis of the effects of toxic, therapeutic and sub-therapeutic concentrations of digitoxin on lung cancer cells.

Digitoxin belongs to a naturally occurring class of cardiac glycosides (CG); digitoxin is clinically approved for heart failure and known for its anti-cancer effects against non-small lung cancer cells (NSCLC). However, concerns associated with its narrow therapeutic index and its concentration-dependent mechanism of action are rising. Thus, before digitoxin implementation in designing and developing safer and more effective CG-based anti-cancer therapies, its pharmacological and safety profiles need to be fully elucidated. In this research we used a combinatorial approach to evaluate the anti-cancer mechanisms of digitoxin in real-time. Our approach employed a non-invasive electric cell impedance sensing technique as a proxy to monitor NSCLC behavior post-exposure to toxic, therapeutic and sub-therapeutic concentrations of the drug. By developing structure-function combinatorial relations we showed that digitoxin targets cancer cells in a time and dose-dependant manner by activating pro-apoptotic and anti-proliferative signaling cascades that results in strengthening cellular adhesion and sequestration of key regulatory proliferation protein from the nucleus.

The prevalence of antibodies to hepatitis C virus in Hail region, Saudi Arabia.

The prevalence of subjects positive for anti-HCV antibodies was studied at Hail region Kingdom of Saudi Arabia (KSA). The study involved 8862 subjects tested for anti-HCV antibodies at King Khalid General Hospital during the years 1994-Using Elisa, a total prevalence of 5.09% positive subjects was found. The disease is shown to be mainly acquired at school age and adulthood. Unlike hepatitis B virus, vertical transmission among preschool children does not seem to have an important role in transmission of HCV virus. Egyptians had a high prevalence of 26% as compared to other expatriates. Blood donors had a prevalence of 4.3% which is higher than that reported from other regions in Saudi Arabia. Medical staff had a prevalence rate of 2.2% indicating a relatively low risk of infection. Dialysis patients had a prevalence of 6.9% which is lower than that reported from other regions in Saudi Arabia. The higher prevalence of HCV infection in Hail (which has a lower socioeconomic status) compared to those in Riyadh and Eastern province suggests the possibility of other modes of transmission.

Sequestration and microsomal C-25 hydroxylation of [3H]-vitamin D3 by the rat liver.

A study of the vitamin D3 (D3) 25-hydroxylase was undertaken in an in vivo-in vitro model. [3H]-D3 (0.7, 1.0, 10, or 100 nmol/100 g of body weight) was injected into the portal vein and the liver was excised 18 seconds later. The liver homogenate was then submitted to differential centrifugation and the amount of [3H]-D3 incorporated in the subcellular fractions was evaluated. The microsomal fraction was also incubated in vitro and the appearance of [3H]-25-hydroxyvitamin D3 [25(OH)D3] was determined by high performance liquid chromatography (HPLC). Results showed that the fractional liver [3H]-D3 uptake varied between 37 percent and 48 percent of the dose injected. The intracellular distribution of [3H]-D3 showed that most of the vitamin was incorporated into the microsomal fraction (45% to 50% of the intracellular [3H]-D3) except at the highest dose of [3H]-D3 where the cytosolic fraction contained the highest amount (56.4%) of the incorporated vitamin. Mathematical analysis of the intracellular [3H]-D3 distribution showed that the microsomal fraction was the only subcellular fraction that was found to incorporate [3H]-D3 in relation to the total liver uptake of the vitamin. The apparent Michaelis-Menten kinetics of the [3H]-D3-25-hydroxylase showed that with substrate concentration of up to 88.5 nM, the apparent Km and Vmax were 28.2 nM and 25.8 fentomoles (fmol) X min-1 X mg microsomal pro-1, respectively, but the reaction lost considerable efficiency with higher substrate concentrations. With the in vivo-in vitro model used, the cytosolic fraction was not essential for the optimal C-25 hydroxylation of D3. These results show that the endoplasmic reticulum of rat hepatocytes possess a high capacity for D3 incorporation.(ABSTRACT TRUNCATED AT 250 WORDS)