Corpus callosum and optic chiasm in early blind adults

Certain callosal dimensions, callosal areas, and the optic chiasm [OC] thickness were measured in order to detect any morphometric difference that would imply plastic changes in a selected group of adults. Seventeen early blinds were selected among a group of blind adults after performing interviews. These selected blind subjects, and 23 adults with normal vision of both genders were examined by MRI. The study was conducted in Mersin, Turkey between the years 2004 and 2006. Only 14 early blind subjects completed the MR imaging procedure. Statistically significant difference between the OC thicknesses of 2 groups was found whereas no statistically significant difference was detected for the callosal dimensions. The difference in the OC dimensions of the 2 groups may be explained by the disuse atrophy. It has been known that if a cortical area of any sense is deprived of stimulus within the critical period, then it may take on another cortical activity. The reasons for the unaffected dimensions of the corpus callosum [CC] in this study may be either the relatively small percentage of the fibers related to vision within the total CC, such as auditory function, of the "normally" visual cortex

Cytokine profile and nitric oxide levels in sera from patients with brucellosis

The aims of this study were to investigate the serum levels of some cytokines [tumor necrosis factor-alpha (TNF-alpha), interleukin 1ß (IL-1ß), IL-2R, IL-6, and IL-8] and nitric oxide (NO) levels in patients with untreated brucellosis and to test the correlation of these parameters with each other. The study was conducted on 67 subjects, 37 patients with brucellosis and 30 healthy individuals with no history of Brucella infection. Brucellosis was identified by a positive blood culture and/or increased Brucella antibodies in serological tests in addition to compatible clinical symptoms. Cytokine profile analysis was performed by the immulite chemiluminescent enzyme immunometric assay whose inter- and intra-assay coefficients of variance were 2.6-3.6 and 4.4-8.5 percent, respectively. The levels of nitrites/nitrates, which are representative of NO levels, were measured by the Griess method. Patients with brucellosis had significantly elevated serum levels of nitrites/nitrates, IL-2R, IL-6 and IL-8 (mean ± SD, 102.8 ± 23.8 æmol/l, 806.1 ± 58.5 U/ml, 21.1 ± 2.3 pg/ml, and 8.8 ± 1.6 pg/ml, respectively) compared to healthy controls, whereas TNF-alpha and IL-1ß levels were unchanged. No statistically significant correlation was detected between any of the studied cytokine levels and nitrate/nitrite concentrations according to Pearson's linear correlation test. We conclude that only IL-6, IL-8 and IL-2R are elevated in brucellosis and the extent of elevation depends on the severity and clinical pattern of the disease. Moderate elevation in serum NO was comparable to that observed in previous studies. This explains the absence or very rare occurrence of septic shock in brucellosis.