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101.
Tatsuya Ishiguro Yoshikatsu Ozaki M. Mitsuo Yokoyama C. Howard Tseng William Chao 《Immunobiology》1980,157(1):24-29
Peripheral blood samples from 52 women including 16 with herpes genitalis and 36 healthy persons were studied to enumerate subpopulations of lymphocytes. T lymphocyte counts were done by SRBC rosette tests and B lymphocytes by immunobead rosette tests using antibody-coated polyacrylamide beads. It was found that the mean percentage of «active T lymphocytes was significantly less in the patients with herpes genitalis than in the controls (herpes genitalis; 13.9 ± 6.8%, controls; 25.0 ± 8.3%, p < 0.001). No difference was noted in the percentage of «total» T lymphocytes, «total» B lymphocytes and subsets of B lymphocytes (IgG-, IgA- and IgM-bearing lymphocytes) between the patients and controls. The present findings suggest that cell-mediated immune function associated with «active» T lymphocytes is suppressed in patients with herpes genitalis. 相似文献
102.
Bonnie B. Punske Wayne E. Cascio Connie Engle H. Troy Nagle Leonard S. Gettes Timothy A. Johnson 《Annals of biomedical engineering》1998,26(6):1010-1021
This study applied zero-delay wave number spectral estimation as a means of quantifying the changes in activation and recovery sequences of propagating plane waves on the epicardial surface of in situ porcine hearts during regional hyperkalemia and ischemia. Unipolar electrograms (104) were recorded from the left ventricular surface of nine hearts using a plaque electrode array with 1 mm spatial sampling intervals. The objectives were (1) to define a set of parameters capable of quantifying the spatial and temporal changes in measured extracellular potentials associated with localized ischemia prior to the onset of conduction block; (2) to elevate regional levels of extracellular potassium ion concentration and quantify potential changes due to this known physiologic manipulation; and (3) to use quantitative parameters to make statistical comparisons in order to distinguish wave fronts during normal, ischemic and hyperkalemic conditions. Results showed that the parameters of wave number and average temporal frequency and the associated power, as determined from the wave number spectrum, provided statistically significant (p < 0.05) quantification of changes in wave front features during normal and ischemic or hyperkalemic conditions. The results were consistent with results obtained from conventional time–space domain methods like isochronal mapping and electrograms, with the advantage of a quantitative result enabling simple comparisons and trend analysis for large numbers of heart beats. © 1998 Biomedical Engineering Society.
PAC98: 8759Wc, 8722Fy, 8780+s 相似文献
103.
104.
Morita Y Ujike H Tanaka Y Uchida N Nomura A Ohtani K Kishimoto M Morio A Imamura T Sakai A Inada T Harano M Komiyama T Yamada M Sekine Y Iwata N Iyo M Sora I Ozaki N Kuroda S 《Neuroscience letters》2005,376(3):182-187
Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia. 相似文献
105.
Takehara H Tada S Kataoka M Matsuo K Ueno Y Ozaki S Miyake T Fujimori Y Yamadori I Harada M 《Acta medica Okayama》2001,55(4):205-211
This study focuses on a possible role of intercellular adhesion molecule-1 (ICAM-1) in interstitial pulmonary diseases. We determined a soluble form of ICAM-1 in serum and bronchoalveolar lavage fluid (BALF) using ELISA in patients with usual interstitial pneumonia (UIP), bronchiolitis obliterance organizing pneumonia (BOOP), or nonspecific interstitial pneumonia (NSIP). In addition, we investigated the expression of ICAM-1 in the lung tissues of these patients by means of immunohistochemical staining. Serum levels of soluble ICAM-1 were significantly higher in patients with UIP or NSIP than in healthy subjects, and were also high in patients with BOOP. The soluble ICAM-1 in BALF tended to be higher in patients with UIP, BOOP, or NSIP than in normal subjects. A significant correlation was seen between soluble levels of ICAM-1 in serum and BALF. In the immunostaining of ICAM-1 of the lung tissues, ICAM-1 expression was more pronounced in patients with UIP than in those with BOOP or NSIP. The increased expression of ICAM-1 was seen in type II alveolar epithelium and vascular endothelium in patients with interstitial pneumonia. A positive correlation was observed between the degree of ICAM-1 expression in the lung tissues and the BALF levels of soluble ICAM-1. The expression of ICAM-1 in type II alveolar epithelium suggests that ICAM-1 plays a specific role in the fibrotic process of the lung, and that the measurement of soluble ICAM-1 in sera and BALF could be a useful marker for evaluating the progression of fibrosis. 相似文献
106.
Rapid diagnosis of human herpesvirus 6 infection by a novel DNA amplification method, loop-mediated isothermal amplification 总被引:13,自引:0,他引:13
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Ihira M Yoshikawa T Enomoto Y Akimoto S Ohashi M Suga S Nishimura N Ozaki T Nishiyama Y Notomi T Ohta Y Asano Y 《Journal of clinical microbiology》2004,42(1):140-145
A novel nucleic acid amplification method, termed loop-mediated isothermal amplification (LAMP), which amplifies DNA with high specificity, efficiency, and rapidity under isothermal conditions, may be a valuable tool for the rapid detection of infectious agents. LAMP was developed for human herpesvirus 6 (HHV-6), and its reliability was evaluated in this study. Although LAMP products were detected in HHV-6 B and HHV-6 A DNA, they were not detected in HHV-7 and human cytomegalovirus DNA. The sensitivity of the original HHV-6 LAMP protocol was 50 copies/tube. In order to increase the method's sensitivity, HHV-6 LAMP was modified by increasing the primer concentration. As a result of the modification, sensitivity increased to 25 copies/tube. After these initial validation studies, 13 patients with fever were tested for HHV-6 by viral isolation, serological analysis, and HHV-6 LAMP. In three of the eight patients with primary HHV-6 infection, HHV-6 DNA was detected in whole blood by the original HHV-6 LAMP protocol in not only the acute phase but also the convalescent phase. HHV-6 DNA was detected by modified HHV-6 LAMP in all eight plasma samples collected in the acute phase; however, no HHV-6 DNA was detected in plasma samples collected in the convalescent phase. Although HHV-6 DNA was detected in both the acute and convalescent phases of whole-blood samples in patients with past HHV-6 infection, it was not detected in plasma samples that did not contain latent viral DNA. Thus, detection of HHV-6 DNA in plasma by using this modified HHV-6 LAMP protocol is appropriate for diagnosis of active HHV-6 infection. 相似文献
107.
108.
109.
Immunoprecipitation of radiolabeled polypeptides from complex mixtures of proteins was performed in polystyrene microtiter plates using staphylococcus protein A and various antibody preparations. The method is (1) rapid, (2) uses multichannel micropipettor technology, (3) handles large numbers of specimen easily, (4) requires very small volumes of antigen and antibody (5–50 μl), (5) provides replicates for statistical analysis and (6) allows recovery of precipitated proteins for direct SDS-PAGE analysis of precipitated proteins. We have shown it is useful as a test to screen large numbers of sera or to characterize monoclonal antibody-containing samples. 相似文献
110.
Joseph. H. Lee Maruit Chulikavit Deborah Pang Warren B. Zigman Wayne Silverman Nicole Schupf 《Neuroscience letters》2007
Recent reports have suggested that variants in the sortilin-related receptor gene (SORL1) increase the risk of late onset Alzheimer's disease (AD) in Northern European, Hispanic, African–American and Isreali–Arab populations. SORL1 directs trafficking of amyloid precursor protein (APP) and under-expression of SORL1 may lead to over-expression of β amyloid peptides. Adults with Down syndrome (DS) over-express APP and have early onset and high risk for AD. We investigated the relation of seven variants in the gene for SORL1 to age at onset and risk for AD among 208 adults with DS, 45–70 years of age at baseline. Participants were ascertained through the New York State developmental disability service system and followed at 18-month intervals. Information from cognitive assessments, caregiver interviews, medical record review and neurological examination was used to establish the diagnosis of dementia. Homozygosity for the minor T allele in rs556349 and for the minor C allele in rs536360 was associated with later age at onset and reduced risk of AD (HR = 0.26, 95% CI: 0.08–0.86; and HR = 0.40, 95% CI: 0.16–0.98, respectively). Mean age at onset was approximately four years later in individuals who were homozygous for those alleles compared with those who had at least one major allele. These findings indicate a modest association of variants in SORL1 with AD. In addition, we did not observe the same alleles to be associated with AD compared with earlier studies, suggesting that these SNPs are in linkage disequilibrium (LD) with the putative functional variants or that expression of the SORL1 gene and hence its interaction with APP might be modified by the extremely high levels of APP characteristic of Down syndrome. Thus, further studies are needed to identify functional variants that influence risk for AD in this uniquely vulnerable population. 相似文献