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971.
Novel cognitive improving and neuroprotective activities of Polygala tenuifolia Willdenow extract,BT-11 总被引:2,自引:0,他引:2
Park CH Choi SH Koo JW Seo JH Kim HS Jeong SJ Suh YH 《Journal of neuroscience research》2002,70(3):484-492
We carried out this study to search a new active constituent that had cognitive enhancing activity and low side effects from natural source. We found that the extract of dried root of Polygala tenuifolia Willdenow (BT-11, 10 mg/kg, i.p.) could significantly reverse scopolamine-induced cognitive impairments in rat, using a passive avoidance and a water maze test. We also investigated the effects of BT-11 on neurotoxicity induced by glutamate (Glu) and toxic metabolites of amyloid precursor protein (APP) such as amyloid beta protein (A beta) and C-terminal fragment of APP (CT) in primary cultured neurons of rat. The pretreatment of BT-11 (0.5, 3, and 5 micro g/ml) significantly reduced cell death induced by Glu (1 mM), A beta (10 micro M) and CT105 (10 micro M) in a dose-dependent manner. In addition, BT-11 inhibited acetylcholinesterase (AChE) activity in a dose-dependent and non-competitive manner (IC(50) value; 263.7 micro g/ml). Our novel findings suggest the possibility that this extract may have some protective effects against neuronal death and cognitive impairments in Alzheimer's disease (AD), or other neurodegenerative diseases related to excitotoxicity and central cholinergic dysfunction. 相似文献
972.
Kim JM Shin IS Jeong SJ Gormley N Yoon JS 《International journal of geriatric psychiatry》2002,17(2):101-106
BACKGROUND: Many studies have sought to determine the predictors of institutionalization of patients with dementia. Such studies, performed in developed western societies, have come to various conclusions which may not be supported in an East Asian culture such as that found in Korea. OBJECTIVES: This study aimed to determine the factors that predict institutionalization of patients in Korea diagnosed with dementia. METHODS: Seventy-nine cases (37 institutionalized, 42 community-dwelling) in the Kwangju area were evaluated for patient characteristics, severity of dementia symptoms, caregiver characteristics, burden and distress. Logistic regression was performed to determine predictors of actual institutionalization. RESULTS: Six predictors of institutionalization were identified. Of these, three were patient-related factors: higher score on the Clinical Dementia Rating, higher score on the Brief Psychiatric Rating Scale, and shorter duration of dementia. The other three were caregiver-related factors: younger age, higher education (formal schooling), and higher cost of home care. CONCLUSIONS: As seen in previous western studies, institutionalization of dementia sufferers was influenced by both patient and caregiver factors. But, the specific predictors and their relative influences might be explained best by the particular social, cultural and economic situation in Korea. This study was the first of its kind in Korea and, as such, could serve as a reference for future intra-cultural and cross-cultural comparisons. 相似文献
973.
Genistein-induced apoptosis of p815 mastocytoma cells is mediated by Bax and augmented by a proteasome inhibitor,lactacystin 总被引:3,自引:0,他引:3
Park BS Baek SJ Song KH Kim KH Jeong SJ Jeong MH Seo SY Lee SW Yoo KS Yoo YH 《Nutrition and cancer》2002,42(2):248-255
Although genistein has been demonstrated to induce apoptosis of various cells, there is no report of its effect on mast cell proliferation. Here we show that genistein reduced the viability of mast cell tumor cell lines, p815 and RBL-2H, but not of a human mast cell line, HMC-1. Further investigation on its growth-inhibitory mechanism was undertaken on p815 mastocytoma cells. Genistein induced G2/M arrest and subsequent apoptotic death. p815 cells undergoing apoptosis showed many apoptotic manifestations, such as reduction of mitochondrial membrane potential, release of cytochrome c to cytosol, translocation of apoptosis-inducing factor to nucleus, activation of caspase-3, nuclear condensation, and generation of DNA fragmentation. Genistein treatment resulted in the increase of Bax expression and its translocation into mitochondria, whereas expression levels of Bcl-2 remained unchanged. Proteasome activity decreased at the early time points after genistein treatment, but thereafter it fluctuated at increased levels. A proteasome inhibitor, lactacystin, potentiated the induction of apoptosis. Taken together, genistein-induced apoptosis of p815 mastocytoma cells is at least in part mediated by proteasome, Bax, apoptosis-inducing factor, and caspase and augmented by cotreatment with a proteasome inhibitor, lactacystin. 相似文献
974.
Iosef C Van Nguyen T Jeong Ki Bengtsson K Morein B Kim Y Chang KO Azevedo MS Yuan L Nielsen P Saif LJ 《Vaccine》2002,20(13-14):1741-1753
The undesirable side effects and variable efficacy of some oral live rotavirus vaccines in infants have necessitated alternative vaccine approaches. We evaluated a recombinant RFVP2/WaVP6 rotavirus-like-particle (2/6VLP) oral vaccine, using an immunostimulating complex (ISCOM) matrix as adjuvant, in a gnotobiotic (Gn) pig model of human rotavirus (HRV) disease. The 2/6VLPs adhered to the ISCOM-matrix (2/6VLP-ISCOM ) and were antigenic, but they failed to induce protection. However, when combined with attenuated (Att) HRV for oral priming, the 2/6VLP-ISCOM vaccine was effective as a booster and induced partial protection against virulent Wa HRV. The 250 microg 2/6VLP dose was more effective than 100 microg. The highest mean numbers of IgA antibody secreting cells evaluated by ELISPOT in intestinal lymphoid tissues were in pigs receiving AttHRV+2/6VLP-ISCOM or three doses of AttHRV and were associated with the highest protection rates. 相似文献
975.
Migraine and isolated recurrent vertigo of unknown cause 总被引:4,自引:0,他引:4
Chronic recurrent attacks of vertigo, not associated with any auditory or neurological symptoms, are a common reason for referral to our neurotology clinic. Even after an extensive neurotological evaluation, some cases remain undiagnosed. We prospectively evaluated 72 consecutive patients who presented to the clinic with isolated recurrent vertigo of unknown cause. All patients underwent diagnostic evaluation to exclude identifiable causes of isolated recurrent vertigo. We compared the prevalence of migraine, according to the International Headache Society (IHS) criteria, in the isolated recurrent vertigo group, with a sex- and age-matched control group of orthopedic patients. The prevalence of migraine according to IHS criteria was higher in the isolated recurrent vertigo group (61.1%) than in the control group (10%; p < 0.01). Only 16.7% of patients had an abnormal vestibular function test. The most common abnormal finding was a unilateral vestibular weakness to caloric stimulation. Our results suggest that migraine should be considered in the differential diagnosis of isolated recurrent vertigo of unknown cause. 相似文献
976.
977.
978.
Jeong HJ Min JJ Park JM Chung JK Kim BT Jeong JM Lee DS Lee MC Han SK Shim YS 《Nuclear medicine communications》2002,23(9):865-870
The aim of this study was to determine whether quantitative information obtained from [(18)F]fluorodeoxyglucose positron emission tomography ((18)F-FDG PET) has a prognostic significance for patients with non-small cell lung cancer (NSCLC). We investigated (18)F-FDG PET imaging of 73 patients with NSCLC. The maximum standardized uptake value (SUV(max)) was significantly different between the histopathological types of tumour (squamous cell carcinoma (n=37, 12.4+/-5.1), adenocarcinoma (n=30, 8.2+/-5.8), bronchioloalveolar carcinoma (n=4, 2.6+/-1.7), <0.01). In the univariate analysis of all patients, staging (P=0.0001), tumour cell type (P=0.013), and a SUV(max) greater than 7 (P=0.0011) was correlated with survival. However, a multivariate analysis identified staging and SUV(max) greater than 7 were affected survival adversely. The mortality rate of patients with group I disease (stage I to stage IIIA) was 5.8 times lower than that of patients with group II disease (stage IIIB to stage IV). Patients with a high SUV(max) (> or =7) had a 6.3 times higher mortality than those with a low SUV(max)(<7). By multivariate analysis of patients with squamous cell carcinoma, only grouping affected survival (P=0.008, relative risk=4.3). In the case of adenocarcinoma, the SUV(max) (>10) correlated exclusively with poorer survival (P=0.031, relative risk=11.152). (18)F-FDG uptake correlated with survival in NSCLC. Especially in adenocarcinomas, the SUV(max) was complementary to other known prognostic factors. 相似文献
979.
Heterotopic paragonimiasis in the omentum 总被引:1,自引:0,他引:1
Jeong WK Kim Y Kim YS Park DW Park CK Baek HK Park YW 《Journal of computer assisted tomography》2002,26(6):1019-1021
Paragonimus westermani is a lung fluke but may be found in organs other than the lungs. A case of omental paragonimiasis was found incidentally by plain radiography and computed tomography and showed multiple, irregularly shaped, conglomerated calcifications in the intraperitoneum. Many P. westermani ova were detected in the resected omentum. This uncommon calcification on the plain abdominal radiography and computed tomography scan was considered to represent radiologic findings of ectopic paragonimiasis. 相似文献
980.
Thirteen patients with gallbladder disease underwent power Doppler ultrasound (PDUS) before and after microbubble contrast agent injection. Lesion and liver bed vascularity was evaluated. Pathological diagnoses in nine patients were two acute cholecystitis, four chronic inflammation, one adenoma and two adenocarcinoma. Two cases of cancer were included on clinical and radiological findings. Two cases were excluded because no pathologic diagnosis was available. Liver bed hyperemia was noted only in acute cholecystitis. Contrast-enhanced PDUS was superior to nonenhanced PDUS in the demonstration of vascularity of gallbladder diseases. However, contrast-enhanced PDUS has limited value in the differentiation. 相似文献