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1.
Oren S Cohen Eli Vakil David Tanne Zeev Nitsan Roseline Schwartz Sharon Hassin-Baer 《Cognitive and behavioral neurology》2007,20(1):68-72
OBJECTIVES: To test a possible association between the educational level (EL), cognitive performance, and neuropsychiatric features in Parkinson disease (PD). BACKGROUND: An inverse association has been reported between EL and cognitive dysfunction in patients with senile dementia of Alzheimer type but it is yet unsettled whether education has a similar effect on cognition in PD. METHODS: Seventy-two PD patients (45 males, mean age 68.7+/-11.6 y) underwent a detailed neurologic examination, a battery of neuropsychologic tests, and questionnaires for the evaluation of psychosis, sleep disturbances, and depression. According to the number of educational years, patients were divided into 3 groups: low EL (0 to 8 y), (15 patients), intermediate EL (9 to 12 y) (28 patients), and high EL (>/=13 y) (29 patients). RESULTS: Patients with a higher EL had a better cognitive function and an association was found between the patients' EL and their scores in various neuropsychologic tests mainly those sensitive to frontal lobe dysfunction. Low education was associated with an increased risk for hallucinations and a trend for more depression, delusions, and sleep disturbances. CONCLUSIONS: The association between high educational attainment and the lower risk of cognitive dysfunction suggest that education might modulate cognitive performance in PD. 相似文献
2.
Andrea Berger Michelle Sadeh Gabriel Tzur I Avinoam Shuper Liora Kornreich Dov Inbar Ian J Cohen Shalom Michowiz Isaac Yaniv Shlomi Constantini Eli Vakil 《Journal of the International Neuropsychological Society》2005,11(4):482-487
Cerebellar involvement in motor and non-motor sequence learning was examined with serial reaction time tasks (SRT). Our sample consisted of 8 children and adolescents who had undergone surgical removal of a benign posterior fossa tumor (PFT) during childhood. None of them had undergone chemotherapy or cranial radiation therapy (CRT). Ages ranged from 1-11 years at surgery and 9-17 years at testing. The children were tested not earlier than 2.5 years after surgery (M = 5.9 years), enabling brain plasticity and recovery of functions. Their performance was compared with a matched control sample. The PFT group was not impaired in the implicit learning of sequences, as reflected in their performance in blocks with a repeated sequence, both before and after a random block. However, in the perceptual task, their performance deteriorated more than that of the control group when a random block was introduced, suggesting that it was more difficult for the patients to respond flexibly or change their response set when encountering changing task demands. These results are in line with another study by our group on task switching with the same patients. 相似文献
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Localization of Helicobacter pylori urease and heat shock protein in human gastric biopsies. 总被引:7,自引:0,他引:7
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B E Dunn N B Vakil B G Schneider M M Miller J B Zitzer T Peutz S H Phadnis 《Infection and immunity》1997,65(4):1181-1188
Helicobacter pylori is a spiral, gram-negative bacterium which causes chronic gastritis and plays a critical role in peptic ulcer disease, gastric carcinoma, and gastric lymphoma. H. pylori expresses significant urease activity which is an essential virulence factor. Since a significant fraction of urease activity is located on the surface of the bacterium, the urease molecule is a logical choice as an antigen for a vaccine; currently recombinant urease apoenzyme is being tested as a vaccine in phase II clinical trials. We have recently demonstrated that urease and HspB (a homolog of the GroEL heat shock protein) become associated with the surface of H. pylori in vitro in a novel manner: these cytoplasmic proteins are released by bacterial autolysis and become adsorbed to the surface of intact bacteria, reflecting the unique characteristics of the outer membrane. To determine if similar mechanisms are operative in vivo, we determined the ultrastructural locations of urease and HspB within bacteria present in human gastric biopsies. Our results demonstrate that both urease and HspB are located within the cytoplasm of all bacteria examined in human gastric biopsies. Interestingly, a significant proportion of the bacteria examined also possessed variable amounts of surface-associated urease and HspB antigen (from 5 to 50% of the total antigenic material), indicating that in vivo, H. pylori has surface characteristics which enable it to adsorb cytoplasmic proteins. This is consistent with our altruistic autolysis model in which H. pylori uses genetically programmed bacterial autolysis to release urease and other cytoplasmic proteins which are subsequently adsorbed onto the surface of neighboring viable bacteria. These observations have important implications regarding pathogenesis and development of vaccines for H. pylori. 相似文献
8.
It is controversial whether gastrooesophageal reflux disease represents a spectrum disease from a nonerosive to a complicated one, or whether it is a categorial disease, i.e. it can be divided into three categories, such as nonerosive gastrooesophageal reflux disease, erosive gastrooesophageal reflux disease and Barrett's esophagus (BE) with little or no transition from one category to the other. This controversy might be of general interest, because it has some implications in the management of the patient. However, literature data concerning the natural history of gastrooesophageal reflux disease are very limited, and in particular very few papers have dealt with the issue of describing the natural history of patients with nonerosive gastrooesophageal reflux disease. Aim of the present review is to reassess these scanty data, and to try to demonstrate that progression from milder to more severe forms of gastrooesophageal reflux disease is possible and documented. 相似文献
9.
Arvydas Vanagunas M.D. Pothen Jacob M.D. Nimesh Vakil M.D. 《The American journal of gastroenterology》1989,84(4):383-385
Patients with diminutive polyps in the rectum or sigmoid colon were randomized to "hot biopsy" treatment for either 1) electrocautery for 2 s (fixed duration cautery) or 2) cautery until visible necrosis of the polyp base was evident (variable duration cautery). Sigmoidoscopy was performed 4 wk after treatment to determine the adequacy of polyp eradication. In the fixed duration cautery group, 11 of 21 polyps (52%) were eradicated, compared with 12 of 14 polyps (86%) in the variable duration cautery group (p = 0.04). When analyzed according to whether or not visible necrosis was achieved (some of the polyps in the fixed duration cautery group showed necrosis with 2 s cautery), 19 of 23 polyps (83%) were eradicated when necrosis was evident, compared to 5 of 12 (42%) without necrosis (p = 0.004). We conclude that hot biopsy treatment for diminutive polyps is significantly more effective when visible necrosis is achieved during cautery. Furthermore, even with visible necrosis, there is a 17% failure rate of polyp eradication. 相似文献
10.
In inbred strains of mice, antiphosphorylcholine (PC) and anti-α1,3 dextran (DEX). antibodies
are structurally distinct from each other and have been shown to exhibit noncrossreactive
antigen binding and idiotypic specificities. However, the prototype anti-PC and
anti-DEX antibodies, TEPC15 and J558, respectively, were shown to be connected via a
common autoantiidiotypic monoclonal antibody isolated from newborn BALB/c mice. The
capacity of various monoclonal anti-PC and anti-DEX antibodies as well as the antigens PC
and DEX to modulate T15 and J558 idiotypes in BALB/c mice was tested by their administration
to newborn mice. Anti-PC antibodies of the .T15 idiotype injected into 2-4-day-old
mice, at a time when T15 anti-PC precursors develop in BALB/c mice, suppressed the anti-
PC response of these mice at 6 weeks of age. Similarly, J558 antibodies injected into 8-12-day-old mice, at a time when J558 precursors normally develop, suppressed the response to
DEX. As a further demonstration of this connectivity, the injection of J558 into 4-day-old
mice led to a down modulation of T15 idiotype, whereas both T15 and a minor idiotypeexpressing
antibody M167 when injected into 8-12-day-old mice caused a reduction in
expression of the J558 idiotype. As predicted from in vitro analysis, injection of anti-PC
antibodies of the M167 idiotype 2 to 4 days after birth enhanced the subsequent response to
PC. However, anti-PC antibodies expressing another minor M603 idiotype did not affect the
PC. response. The results parallel the in vitro enhancement of M167 antibodies but not M603
on T15 binding to antiidiotype in vitro. Similarly, anti-DEX antibodies expressing the M104E
idiotype had no detectable effects on the capacity to respond to PC or DEX or on the expression
of T15 and J558 idiotypes as adults. Exposure of newborn mice to PC led to a dramatic
reduction in the response to DEX as adults, whereas exposure to DEX at this stage of
development had no effect on response to PC as adults. Collectively, these observations provide
evidence for a complex functional connectivity between T15 and J558 idiotype-bearing B
cells during ontogeny and extend our previous observations that development of these idiotypes
is regulated by idiotype-directed interactions between B cells or their immunoglobulin
products. 相似文献