The influence of gender on auditory and language cortical activation patterns: preliminary data

PURPOSE AND BACKGROUND: Intersex cortical and functional asymmetry is an ongoing topic of investigation. In this pilot study, we sought to determine the influence of acoustic scanner noise and sex on auditory and language cortical activation patterns of the dominant hemisphere. MATERIALS AND METHODS: Echoplanar functional MR imaging (fMRI; 1.5T) was performed on 12 healthy right-handed subjects (6 men and 6 women). Passive text listening tasks were employed in 2 different background acoustic scanner noise conditions (12 sections/2 seconds TR [6 Hz] and 4 sections/2 seconds TR [2 Hz]), with the first 4 sections in identical locations in the left hemisphere. Cross-correlation analysis was used to construct activation maps in subregions of auditory and language relevant cortex of the dominant (left) hemisphere, and activation areas were calculated by using coefficient thresholds of 0.5, 0.6, and 0.7. RESULTS: Text listening caused robust activation in anatomically defined auditory cortex, and weaker activation in language relevant cortex of all 12 individuals. As a whole, there was no significant difference in regional cortical activation between the 2 background acoustic scanner noise conditions. When sex was considered, men showed a significantly (P < .01) greater change in left hemisphere activation during the high scanner noise rate condition than did women. This effect was significant (P < .05) in the left superior temporal gyrus, the posterior aspect of the left middle temporal gyrus and superior temporal sulcus, and the left inferior frontal gyrus. CONCLUSION: Increase in the rate of background acoustic scanner noise caused increased activation in auditory and language relevant cortex of the dominant hemisphere in men compared with women where no such change in activation was observed. Our preliminary data suggest possible methodologic confounds of fMRI research and calls for larger investigations to substantiate our findings and further characterize sex-based influences on hemispheric activation patterns.     

Electrooculography After Photodynamic Therapy

Purpose: To evaluate the changes in electrooculography (EOG) after photodynamic therapy (PDT). Methods: Thirty-eight eyes of 38 patients (21 males, 17 females) with choroidal neovascularization secondary to age related macular degeneration were included in this study. Standart PDT with verteporfin was performed on each patient. Serial EOG recordings were performed before, 1 week, and 1 month after PDT. Results: Mean age of the patients was 69.8±9.7 years (range 56 and 90 years). Seven days after PDT the visual acuity improved in 17 eyes, remained unchanged in 16 eyes and deteriorated in 5 eyes. One month after PDT the visual acuity findings were the same as the first week. New hemorrhages were seen in three eyes in the first week after PDT and visual acuity was decreased in those patients. No other patient complained of ocular and systemic adverse events. There was a statistically significant reduction in the Arden ratio of the EOG 1 week after PDT and the reduction persisted in the first month recordings. Conclusions: The reduction in Arden ratio of EOG findings may indicate that retina pigment epithelium function could be affected after PDT.     

Diazinon-induced hepatotoxicity and protective effect of vitamin E on some biochemical indices and ultrastructural changes

Diazinon, an organophosphate insecticide has been used in agriculture and domestic for several years. The aim of present study was to analyze the hepatotoxic effect of diazinon which caused biochemical and ultrastructural changes in adult male Wistar rats and to evaluate the possible protective effect of vitamin E. Vitamin E (200 mg/kg, twice a week), diazinon (10 mg/kg per day, once a day in corn oil) and vitamin E (200 mg/kg, twice a week)+diazinon (10 mg/kg per day, once a day in corn oil) combination were given to rats (n=8) orally via gavage for 7 weeks. Biochemical indices in serum [total protein, albumin, alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol, triglyceride and low density lipoprotein cholesterol (VLDL-cholesterol)] and ultrastructural changes were investigated at the end of the 1st, 4th and 7th weeks comparatively with control group (n=8). It was observed that; at the end of 1st week, there was a statistically significance in all parameters except total protein and albumin, and at the end of 4th and 7th weeks, there was a statistically significance in all parameters when diazinon-treated group compared to control group (P<0.01). At the end of 1st week, ALP, ALT, total cholesterol and triglyceride, at the end of 4th week, all parameters except VLDL-cholesterol, at the end of 7th week, all parameters were statistically significant when vitamin E+diazinon-treated group compared with diazinon-treated group (P<0.01). In our electron microscopic investigations, while swelling of mitochondria and breaking up of the mitochondrial cristae of hepatocytes in diazinon-treated groups were observing, no pathological findings were observed in vitamin E+diazinon-treated groups. We conclude that vitamin E decreases diazinon hepatotoxicity, but vitamin E does not protect completely.     

Evaluation of the toxicity and teratogenity of six commercial textile dyes using the frog embryo teratogenesis assay-Xenopus

Potential developmental toxicities of six different textile dyes were evaluated using the frog embryo teratogenesis assay-Xenopus (FETAX). Xenopus laevis embryos were exposed to astrazon red FBL, astrazon blue FGRL, remazol red RR, remazol turquoise blue G-A, cibacron red FN-3G, and cibacron blue FN-R from stage 8 to 11 for a 96-h exposure period in static renewal test conditions. A minimum of 17 concentration-response tests were performed with tested dyes, excluding a control group for each dye. Median lethal concentration (LC50), malformation (EC50), non observed adverse effect concentration (NOAEC), and lowest observed adverse effect concentration (LOAEC) were calculated. Also, teratogenic index (TI), minimum concentration to inhibit growth (MCIG), and MCIG/LC50 values were determined for each of the tested dyes. Characteristic abnormalities induced by a given test material were determined by the relationship between concentration and dye in the study. Results from these studies suggested that each tested dye is teratogenic for X. laevis embryos. The lowest LC50 was determined for astrazon red exposure corresponding to a value of 4.73 mg/L. The LC50 value was similar for this dye and astrazon blue; the highest TI was calculated for astrazon blue exposure. Tests with X. laevis indicated that each of the tested compounds possessed teratogenic potential with varying degrees of potency: astrazon blue FGRL > remazol turquoise blue G-A > astrazon red FBL > cibacron blue FN-R > cibacron red FN-3G > remazol red RR. Different types of malformations occurred in the embryos, depending on concentration and dye. From these results, we can suggest that astrazon blue is the most toxic compound, but that the others are also highly toxic and teratogenic substances for X. laevis embryos. Results of the study confirmed that the FETAX assay can be useful in an integrated biological hazard assesment for the preliminary screening of textile dye stuff.     

Identification and characterization of a functional TATA box polymorphism of the UDP glucuronosyltransferase 1A7 gene

UDP glucuronosyltransferases (UGT) detoxify bilirubin and therapeutic drugs, a process influenced by single nucleotide polymorphisms (SNPs) in their structural genes and promoter elements. UGT1A1*28 is a functional UGT promoter polymorphism associated with Gilbert's disease and severe irinotecan toxicity, which also occurs in the absence of UGT1A1*28. The aim of this study was to identify and characterize UGT promoter variants relevant for irinotecan detoxification. Recombinant UGT1A proteins were analyzed for irinotecan metabolite glucuronidation by UGT activity assays. In 427 healthy blood donors and 71 homozygous UGT1A1*28 carriers, the 5'-untranslated region of the UGT1A7 gene locus was studied. An SNP was detected by allelic discrimination and characterized by reporter gene experiments. A novel -57 T--> G SNP with a gene frequency of 0.39 in healthy blood donors was identified in the putative TATA box of the UGT1A7 gene, reducing promoter activity to 30%. It is in linkage dysequilibrium with a variant of the UGT1A7 first exon that is present in the reduced-activity UGT1A7*3 and UGT1A7*4 alleles. Homozygous UGT1A1*28 carriers simultaneously carried this variant in 97%. We identified a novel reduced-function TATA box SNP of the UGT1A7 gene that catalyzes irinotecan metabolite detoxification. Its association with variants of the UGT1A1 promoter and UGT1A7 gene may influence irinotecan metabolism. Our finding emphasizes the importance of combinations of structural and regulatory gene polymorphisms that may be useful as markers of drug toxicity.     

The relationship between risk factors for falling and the quality of life in older adults

Background  

Falls are one of the major health problems that effect the quality of life among older adults. The aim of this study was to explore the relationship between quality of life (Short Form-12) and the risk factors of falls (balance, functional mobility, proprioception, muscle strength, flexibility and fear of falling) in older adults.     

Postoperative infections in cirrhotic patients

An overview of the impairments of immune function present and the type as well as frequency of infections seen in individuals with advanced liver disease is presented. Where data are available, the use of antibiotic prophylaxis to prevent these complications is identified. Physicians and surgeons caring for individuals with advanced liver disease need to be aware of these issues and be vigilant to the recognition, early detection and aggressive treatment of infections in patients with advanced liver disease and particularly cirrhosis of any etiology.