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11.
12.
Eight cases of spinal brucellosis are included in this study. Diagnosis was established by positive serology. Back pain was the most common complaint. Functional disturbance in walking was observed in three cases; in two others this was because of impairment of cord function. Clinical hepatosplenomegaly was found in one case. Subclinical organomegaly was diagnosed in two other patients. Psoas abscess was identified by computed tomographic scan in two separate cases. Response to drug therapy and surgical decompression, when indicated, resulted in complete recovery in all patients. 相似文献
13.
Our data suggest that DOX resistance in P388/R-84 cells may result, at least in part, from reduced free radical formation by both suppression of flavin reductase(s) and overexpression of certain antioxidant enzymes such as GSH peroxidase and catalase. In addition, our results, in conjunction with other studies, indicate that flavin reductase(s) and antioxidant enzymes are differentially altered in cancer cells with acquired or de novo resistance to DOX. Further studies are needed, however, to elucidate the mechanism(s) by which the gene expression of these enzymes is regulated in drug-sensitive and -resistant cells. 相似文献
14.
Hu WG Thompson HG Alvi AZ Nagata LP Suresh MR Fulton RE 《Journal of immunological methods》2004,289(1-2):27-35
A genetically biotinylated single chain fragment variable antibody (scFv) against Venezuelan equine encephalitis virus (VEE) was applied in a system consisting of an immunofiltration enzyme assay (IFA) with a light addressable potentiometric sensor (LAPS) for the rapid identification of VEE. The IFA involved formation of an immunocomplex sandwich consisting of VEE, biotinylated antibody, fluoresceinated antibody and streptavidin, capture of the sandwich by filtration on biotinylated membrane, and labeling of the sandwich by anti-fluorescein urease conjugate. The concentration ratio of biotinylated to fluoresceinated antibodies was investigated and optimized. By the IFA/LAPS assay, the limit of detection (LOD) of VEE was approximately 30 ng/ml, similar to that achieved when chemically biotinylated monoclonal antibody (mAb) was applied. Total assay variance of the IFA/LAPS assay for both intra- and inter-assay precision was less than 20%. Assay accuracy was measured by comparing VEE concentrations estimated by IFA/LAPS standard curve to those obtained by conventional protein assay. VEE concentrations were found to differ by no more than 10%. The IFA/LAPS assay sensitivity was approximately equal to that of a conventional enzyme-linked immunosorbent assay (ELISA) utilizing polystyrene plates and a chromogenic substrate; however, less time and effort were required for performance of the IFA/LAPS assay. More importantly, use of genetically biotinylated scFv in the IFA/LAPS assay obviates the need for chemical biotinylation of antibody with resultant possible impairment of the antigen-binding site. Furthermore, the potential for batch-to-batch variability resulting from inequality in the number of biotin molecules labeled per antibody molecule is eliminated. 相似文献
15.
Meksem K Njiti VN Banz WJ Iqbal MJ Kassem MM Hyten DL Yuang J Winters TA Lightfoot DA 《Journal of biomedicine & biotechnology》2001,1(1):38-44
Soy products contain isoflavones (genistein, daidzein, andglycitein) that display biological effects when ingested byhumans and animals, these effects are species, dose and agedependent. Therefore, the content and quality of isoflavones insoybeans is a key to their biological effect. Our objective wasto identify loci that underlie isoflavone content in soybeanseeds. The study involved 100 recombinant inbred lines (RIL) fromthe cross of ‘Essex' by ‘Forrest,' two cultivars that contrastfor isoflavone content. Isoflavone content of seeds from each RILwas determined by high performance liquid chromatography (HPLC).The distribution of isoflavone content was continuous andunimodal. The heritability estimates on a line mean basis were79% for daidzein, 22% for genistein, and 88% for glycitein.Isoflavone content of soybean seeds was compared against 150polymorphic DNA markers in a one-way analysis of variance. Fourgenomic regions were found to be significantly associated withthe isoflavone content of soybean seeds across both locations andyears. Molecular linkage group B1 contained a major QTLunderlying glycitein content (P = 0.0001, R2 = 50.2%), linkagegroup N contained a QTL for glycitein (P = 0.0033, R2 = 11.1%)and a QTL for daidzein (P = 0.0023, R2 = 10.3%) and linkagegroup A1 contained a QTL for daidzein (P = 0.0081, R2 = 9.6%).Selection for these chromosomal regions in a marker assistedselection program will allow for the manipulation of amounts andprofiles of isoflavones (genistein, daidzein, and glycitein)content of soybean seeds. In addition, tightly linked markers canbe used in map based cloning of genes associated withisoflavone content. 相似文献
16.
Accumulation of filamentous tau in the cerebral cortex of human tau R406W transgenic mice 总被引:4,自引:0,他引:4
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Ikeda M Shoji M Kawarai T Kawarabayashi T Matsubara E Murakami T Sasaki A Tomidokoro Y Ikarashi Y Kuribara H Ishiguro K Hasegawa M Yen SH Chishti MA Harigaya Y Abe K Okamoto K St George-Hyslop P Westaway D 《The American journal of pathology》2005,166(2):521-531
Missense mutations of the tau gene cause autosomal dominant frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17), an illness characterized by progressive personality changes, dementia, and parkinsonism. There is prominent frontotemporal lobe atrophy of the brain accompanied by abundant tau accumulation with neurofibrillary tangles and neuronal cell loss. Using a hamster prion protein gene expression vector, we generated several independent lines of transgenic (Tg) mice expressing the longest form of the human four-repeat tau with the R406W mutation associated with FTDP-17. The TgTauR406W 21807 line showed tau accumulation beginning in the hippocampus and amygdala at 6 months of age, which subsequently spread to the cortices and subcortical areas. The accumulated tau was phosphorylated, ubiquitinated, conformationally changed, argyrophilic, and sarcosyl-insoluble. Activation of GSK-3beta and astrocytic induction of mouse tau were observed. Astrogliosis and microgliosis correlated with prominent tau accumulation. Electron microscopic examination revealed the presence of straight filaments. Behavioral tests showed motor disturbances and progressive acquired memory loss between 10 to 12 months of age. These findings suggested that TgTauR406W mice would be a useful model in the study of frontotemporal dementia and other tauopathies such as Alzheimer's disease (AD). 相似文献
17.
Md. Iqbal Hossain Chowdhury Yoshio Koyanagi Michihiko Suzuki Susumu Kobayashi Kazuhito Yamaguchi Naoki Yamamoto 《Virus genes》1992,6(1):63-78
Syncytia or multinucleated giant-cell formation is one of the major cytopathic effects induced by human immunodeficiency virus (HIV) infection. Cell fusion results from the strong interaction of CD4 molecules on the surface of the uninfected T cells and gp120, an external envelope glycoprotein of HIV on the infected T cells. We studied the production of HIV in fusion cells between MOLT-4 and virus-infected MOLT-4/HIV cells and found that HIV production was enhanced up to three- to fivefold, which showed a good correlation with the appearance and extent of syncytia formation. Blocking the fusion by monoclonal antibody against a binding epitope of CD4 molecule to gp120 decreased the HIV production significantly. Enhancement of HIV production was observed by more than five-fold in comparison with chronically infected cells, which were fusion free 20 hr postcocultivation. Electron microscopic observation also showed the presence of abundant HIV particles inside the fused cells and on the outer surface. AZT blocked the HIV augmentation of fused cells in coculture completely. Southern blot analysis revealed that both integrated and unintegrated HIV DNA were highly accumulated in fusion cells, as compared with fusion-free MOLT-4/HIV cells. Among unintegrated DNA, circular and linear DNA were accumulated to a similar degree. Northern blot hybridization showed that rapid enhancement of all three species of HIV-specific RNA containing genomic (9.2 kb) and subgenomic (4.3 and 1.9 kb) RNAs were found 20 hr postinfection in fusion cells. These data suggest that syncytia formation is an extremely active infection process of HIV, by which multiple rounds of reinfection might take place. 相似文献
18.
For several years, the primary function of CD40 ligand (CD40L) has been believed to be in regulation of contact-dependent, CD40-CD40L-mediated signals between B-and T-cells, which are essential for the regulation of thymus-dependent (TD) humoral immune responses. Recently, a flurry of reports indicate that CD40 is expressed by variety of cell types other than B-cells that include dendritic cells, follicular dendritic cells, monocytes, macrophages, fibroblasts, and endothelial cells. These studies show that CD40-CD40L interactions are important in inflammatory process. For the past few years, through the availability of CD40L-knockout mice, new data have emerged to support the belief that CD40L has many more functions than its role in TD humoral immunity. CD40L-deficient mice have provided significant information towards our understanding of the in vivo role of CD40L. The current picture that emerges indicates that CD40-CD40L interactions mediate many cell-mediated immune responses and T-cell-mediated effector functions that are required for proper functioning of the host defense system. This article focuses on the in vivo role of the CD40L in regulation of cell-mediated effector functions. 相似文献
19.
Partial duplication 16q: report of two affected siblings resulting from a maternal translocation and literature review 总被引:1,自引:0,他引:1
Two siblings with a partial duplication 16q, born to a woman with a balanced translocation (6;16), are described. The first infant died at 8 weeks of age; the second died at 4 months. Fifteen other cases of duplications involving 16q have been reported, all of them derived from a balanced parental translocation. The most frequent physical findings have included dysmorphic facies characterized by high forehead, prominent nose, antimongoloid slant, malformed ears, and micrognathia, as well as flexion contractures of the joints, deformity of the feet, and genital hypoplasia in the male. Anorectal, intestinal and cardiac malformations were less frequent findings. Most of the affected infants died at ages ranging from 8 days to 6 months. The few with longer survival (up to 6 years) had a shorter, more distal segment duplication of chromosome 16. Although intrauterine growth retardation and microcephaly were not always present at birth, most of the infants had postnatal growth failure. The phenotypic and clinical findings of the two infants in this report are compared with those of previously reported cases, from which there appears to be correlation of the length of the 16q duplication with clinical phenotype and survivals. 相似文献
20.
Protective cytotoxic T lymphocyte responses against paramyxoviruses induced by epitope-based DNA vaccines: involvement of IFN-gamma 总被引:1,自引:0,他引:1
Hsu SC; Obeid OE; Collins M; Iqbal M; Chargelegue D; Steward MW 《International immunology》1998,10(10):1441-1447
Plasmid DNA vectors have been constructed with minigenes encoding a single
cytotoxic T lymphocyte (CTL) epitope from either the M2 protein of
respiratory syncytial virus (RSV) or from the nucleoprotein of measles
virus (MV) with or without a signal sequence (also called secretory or
leader sequence). Following intradermal immunization, plasmids in which the
CTL epitopes were expressed in-frame with the signal sequence were more
effective at inducing peptide- and virus- specific CTL responses than
plasmids expressing CTL epitopes without the signal sequence. This
immunization resulted in protection against MV-induced encephalitis and a
significant reduction in viral load following RSV challenge. The reduction
of viral load following RSV challenge was abrogated by prior injection with
anti-IFN-gamma antibodies. These results highlight the ability of
epitope-based DNA immunization to induce protective immune responses to
well-defined epitopes and indicate the potential of this approach for the
development of vaccines against infectious diseases.
相似文献