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Left and right superior parietal lobule in tactile object discrimination   总被引:3,自引:0,他引:3  
Tactile object discrimination is one of the major manual skills of humans. While the exploring finger movements are not perceived explicitly, attention to the movement-evoked kinaesthetic information gates the tactile perception of object form. Using event-related functional magnetic resonance imaging in seven healthy subjects we found one area in the right superior parietal cortex, which was specifically activated by kinaesthetic attention during tactile object discrimination. Another area with similar location in the left hemisphere was related to the maintenance of tactile information for subsequent object discrimination. We conclude that kinaesthetic information is processed in the anterior portion of the superior parietal cortex (aSPL) with a right hemispheric predominance for discrimination and a left hemispheric predominance for information maintenance.  相似文献   
63.
Obesity-linked insulin resistance is associated with chronic inflammation and cardiovascular complications. Free fatty acids (FFAs) are prominent candidates for the molecular link between these disorders. In this study, we determined whether FFAs contribute to vascular inflammation via induction of interleukin (IL)-6 in coronary artery endothelial cells (CAECs) and coronary artery smooth muscle cells (CASMCs) and whether this is reflected in vivo. In contrast to our findings regarding IL-6 and gp130 (the glycoprotein of 130 kDa) expression, IL-6 receptor mRNA expression was very low in these cells. Palmitate, but not linoleate, induced a significant increase in IL-6 mRNA expression in CAECs (P < 0.001) and, to a less relevant extent, in CASMCs (P < 0.01). gp130 remained unaffected. As to potency, palmitate was comparable with the IL-6-inducer IL-1beta. To substantiate our in vitro data, we examined the plasma FFA pattern in 54 healthy human subjects and studied the relation of individual FFAs with plasma IL-6. IL-6 levels correlated with palmitate, but not with other abundant FFAs, even after adjusting for body fat (r = 0.33, P < 0.05) and total FFAs (r = 0.29, P < 0.05). We show here that the common plasma FFA palmitate induces high levels of IL-6 in CAECs. Furthermore, palmitate correlates with IL-6 in vivo. This points to a potential contribution of palmitate to vascular inflammation.  相似文献   
64.
BACKGROUND: Health departments use reactor grids (sex, age, and serologic test for syphilis [STS] titer criteria) to determine which persons to evaluate for untreated syphilis. GOAL: The goal of the study was to assess reactor grid performance in Chicago and reactor grid use nationally in 1999 to 2000. STUDY DESIGN: We reviewed Chicago health department records to identify characteristics of persons with a reactive STS excluded from evaluation by reactor grid criteria and syphilis cases not meeting evaluation criteria. We surveyed health departments regarding reactor grid use. RESULTS: Of persons with a reactive STS, 46% did not meet criteria for health department evaluation, including 62% of men, 29% of women, and 21% with titers > or =1:8. The reactor grid would have excluded 17% of primary syphilis cases. Overall, 82% of health departments use reactor grids. CONCLUSIONS: Reactor grids are widely used and may exclude persons with infectious syphilis from health department evaluation, especially men. The impact of reactor grid use on syphilis control and surveillance in the United States should be evaluated.  相似文献   
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Ligneous conjunctivitis is a rare and unusual form of chronic pseudomembranous conjunctivitis which usually starts in early infancy. Plasminogen deficiency has recently been associated with ligneous conjunctivitis. The disease may be associated with pseudomembranous lesions of other mucous membranes in the mouth, nasopharynx, trachea, and female genital tract and also with congenital hydrocephalus. In this report, a 1-month-old Turkish boy who had pseudomembranous conjunctivitis, occlusive hydrocephalus, and hydrocele is presented. After surgery for ventriculo-peritoneal shunt establishment, he developed inspiratory stridor, respiratory distress, and pulmonary atelectasis. Tracheal pseudomembranes were also demonstrated by bronchoscopy. Plasminogen antigen level and plasminogen activity were very low. Genomic DNA from the patient was screened for mutations in the plasminogen gene and a homozygous L650fsX652 mutation (deletion of 2081C) was detected. Both of his parents were heterozygous for this mutation. He died due to respiratory failure during follow-up. CONCLUSION: Ligneous conjunctivitis related to type I plasminogen deficiency is relatively common in the Turkish population, however, mutations are heterogeneous and a common founder is unlikely.  相似文献   
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Functional imaging and clinical studies in children and adults have provided evidence of developmental changes in the hemispheric specialization for language. Whereas cytoarchitectonic asymmetry has been demonstrated in Broca's region of adults, the anatomical correlates of developmental changes in language dominance are largely unknown. In the present postmortem study of 34 human brains (ages ranging from 3.5 months to 85 years), the cytoarchitecture of areas 44 and 45 as the putative anatomical correlates of Broca's region, their developmental changes, and interhemispheric asymmetry were analyzed. Asymmetry as estimated by Euclidean distances between feature vectors of cytoarchitectonic profiles of left and right areas 44 and 45 was already found in 1-year-old infants. Asymmetry tended to increase with age, which was significant in area 45, but not in area 44. An adult-like, left-larger-than-right asymmetry in the volume fraction of cell bodies [gray level index (GLI)] was reached at approximately 5 years in area 45 and 11 years in area 44. These time points indicate a delayed development of the cytoarchitectonic asymmetry in Broca's region in comparison with that of the primary motor cortex. It may be hypothesized that the delayed maturation is the microstructural basis of the development of language abilities and the influence of language practice on cytoarchitecture during childhood. Interhemispheric asymmetry in the cytoarchitecture of areas 44 and 45 continues to change throughout life. We conclude that the cytoarchitectonic asymmetry of areas 44 and 45 is a result of microstructural plasticity that endures throughout almost the whole lifespan.  相似文献   
69.
The cellular receptor for urokinase-type plasminogen activator, uPAR, plays a central role in both cell surface-associated proteolysis and cellular adhesion. In the present study, we systematically searched for splice variants of uPAR mRNA in human cells and tumor tissues by qualitative RT-PCR using specific primers for uPAR exons 1 and 6. Beside the wild-type (wt) uPAR mRNA and the previously described splice variant lacking exon 5 (uPAR-del5), a novel splice variant lacking both exons 4 and 5 (uPAR-del4/5) was found predominantly in various cancer cell lines. To elucidate whether alternatively spliced uPAR mRNA may be translated and post-translationally processed, we generated stably transfected Chinese hamster ovary cells, which harbor expression plasmids of wt uPAR and various uPAR variants including uPAR-del5 and uPAR-del4/5. By ELISA, flow cytofluorometry, and Western blot analysis, we confirmed synthesis and secretion of wt uPAR and the uPAR variants by the use of domain-specific monoclonal antibodies against uPAR. For quantification of uPAR mRNA variants, we established two highly sensitive real-time RT-PCR assays based on LightCycler technology. Study of their expression in a representative set of breast cancer tissues indicated that the novel mRNA variant uPAR-del4/5 was expressed very frequently and independently of uPAR mRNA variants covering exon 4 (uPAR-wt and uPAR-del5). Higher uPAR-del4/5 expression was significantly associated with shorter disease-free survival (p = 0.0004) of breast cancer patients. These results suggest that uPAR-del4/5 mRNA may serve as a novel prognostic marker in breast cancer.  相似文献   
70.
Noxious digital nerve stimulation during isometric contraction of hand muscles leads to transient suppression of the electromyographic activity, the so-called cutaneous silent period (CSP), which is mostly due to a spinal reflex mediated by A-delta fibers. We investigated two patients with carpal tunnel syndrome (CTS) and two patients with ulnar entrapment at the elbow (UNE), in whom routine sensory conduction studies failed to document afferent fiber continuity across the lesion site. In three patients, motor nerve conduction studies and electromyography failed to demonstrate intact efferent fibers. Noxious stimulation of digit II elicited distinct CSPs in ulnar-innervated hand muscles in both patients with CTS, and stimulation of digit V evoked CSPs in median-innervated hand muscles in both UNE patients. The presence of a CSP can only be explained by preserved A-delta fibers crossing the respective lesion site. Thus, preserved CSPs may serve to document residual nerve continuity in severe entrapment neuropathies when fast-conducting fibers are so compromised that their continuity cannot be detected by standard electrodiagnostic techniques.  相似文献   
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