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21.
Solid-phase enzyme immunoassay for Chlamydial antibodies.   总被引:1,自引:1,他引:1       下载免费PDF全文
An enzyme immunoassay (EIA) for chlamydial immunoglobulin G antibodies was developed by using microtiter wells coated with partially purified reticulate bodies of Chlamydia trachomatis serotype L2, grown in McCoy cells, and uninfected McCoy cells as a control. Duplicate testing of a single serum dilution, 1:500, was found to be sufficient. A good correlation between positive reactions was observed in a comparative study of 421 patient sera with the EIA and an inclusion immunofluorescence test. A good correlation between positive reactions was also observed in a comparative study of 140 patient sera with EIA and microimmunofluorescence tests in which chlamydial elementary or reticulate bodies were used as antigens. Sera of 77 healthy control individuals with low titers in inclusion immunofluorescence or complement fixation tests gave negative results in the EIA. Immunoblotting experiments showed that the major antigenic component in the EIA antigen was a protein with an Mr of 39,000.  相似文献   
22.
The presence of centromeric DNA was studied in micronuclei isolatedfrom the blood of male ddY mic after five weekly intraperitonealinjections of mitomycu C (MMC), 1-ß-D-arabinofuranosylcytosine(Ara-C), colchi cine (COL) or vinblastine sulfate (VBL). Inagreement with our earlier findings, about half of the micronucleiisolate* from vehicle control mice showed centromere signalsa analyzed by fluorescence in situ hybridization (FISH) witha mouse major (gamma) satellite DNA probe. In an earlie experimentwith mice acutely exposed to the same chem icals, the clastogensMMC and Ara-C did not reduce thi proportion of micronuclei withcentromere signals. In the present study, however, MMC and Ara-Cdecreased the proportion of micronuclei with centromeres. Incontrast the spindle poisons COL and VBL increased the proportionof micronuclei that contained centromeres. 3To whom correspondence should be addressed  相似文献   
23.
Summary Guinea-pigs were treated with chlorpromazine or 0.9% NaCl and exposed to +4° C or +23° C for 2 h. Hypothalamic noradrenaline (NA), dopamine (DA), 5-hydroxytryptamine (5HT), 3-methoxy-4-hydroxyphenylethylene-glycol (MHPG), homovanillinic acid (HVA) and 5-hydroxyindoleacetic acid (5-HIAA) were determined by high-performance liquid chromatography. Serum and urinary catecholamines, muscle and liver glycogen and blood glucose were also measured. Chlorpromazine caused deep hypothermia at this moderately cold temperature and slight hypothermia at room temperature. Cold increased the activity of noradrenergic and serotonergic neurons, as indicated by the increase in hypothalamic MHPG and 5-HIAA and also the MHPG∶NA and 5-HIAA∶5-HT ratios. A tendency towards drug-induced inhibition of hypothalamic serotonergic neurons was seen, although this was not significant. A drug-induced inhibition of noradrenergic neurons could not be ruled out. Increased drug-induced turnover of DA was observed in the cold, and a tendency in the same direction was seen at room temperature. Excretion of DA into the urine was induced by chlorpromazine. The hypothermic guinea-pigs had low serum catecholamines, indicating diminished sympathetic activity, but high urinary catechols, a sign of cold stress.  相似文献   
24.
Lymphocyte homing is initiated by their tethering to and rolling on the high endothelium and is followed by extravasation into the lymph nodes. We show here that glycosylated cell adhesion molecule-1 (GlyCAM-1), CD34, and sialyl Lewis x (sLex) are present on rat lymph node high endothelium analyzed by using monoclonal antibodies. α(1,3)fucosyltransferase VII (Fuc-TVII), the last enzyme involved in the synthesis of the sLex sequence is also expressed on the rat lymph node high endothelium. We have synthesized a family of sLex-decorated oligosaccharide structures and used them to inhibit lymphocyte binding to high endothelium in the Stamper-Woodruff assay. Monovalent sLex, branched di- and tetravalent sLex, as well as a linear tetravalent sLex significantly reduce lymphocyte binding to endothelium. The branched and linear forms of tetravalent sLex were clearly superior inhibitors of the L-selectin-dependent lymphocyte adhesion, with IC50 values in low nanomolar range. In contrast, the fucose-free analogs having the same charge and approximately the same size as the corresponding sLex glycans had no effect on lymphocyte binding and served as negative controls. Taken together, these data show the crucial importance of sLex in the endothelial ligands for L-selectin. Furthermore, we suggest that L-selectin acts as an oligomer on the lymphocyte surface as it binds multivalent sLex glycans.  相似文献   
25.
Familial amyloidosis, Finnish type (FAF) (gelsolin-related amyloidosis) is an autosomal dominant form of systemic amyloidosis characterized by corneal lattice dystrophy and peripheral polyneuropathy. The accumulating protein in FAF consists of fragments of gelsolin, an actin-modulating protein. The gelsolin mutation G654A has been found in both Finnish and Japanese patients. To study the origin of the gelsolin mutation in these patients we performed haplotype analysis in 10 Finnish and 2 Japanese FAF families. Poymorphic DNA markers GSN, D9S103, AFMa061xd9, and AFMa139xb9 revealed a uniform disease haplotype in all the disease-associated chromosomes of the Finnish FAF families, which was different from the one observed in the Japanese families. The present results and the previously detected gelsolin mutation G654T in Czech and Danish FAF patients suggest that nucle otide 654 may represent a mutation hot spot in the gelsolin gene. The DNA markers studied here will be useful in future genealogical analyses of FAF. © 1995 Wiley-Liss, Inc.  相似文献   
26.
Web-based virtual microscopy in teaching and standardizing Gleason grading   总被引:6,自引:0,他引:6  
Gleason grading forms the basis of prognostic and therapeutic assessment in prostatic carcinoma despite its subjective nature and substantial interobserver variation. The accuracy of Gleason grading can be improved by the use of educational tools such as reference images. However, conventional microscopy images are of limited educational value because it is neither possible to view the sample at different magnifications nor to navigate into different areas of the specimen. This limitation can be overcome by the use of virtual microscopy, which allows viewing entire digitized microscope slides. We created an interactive Web site ( www.webmicroscope.net/gleason ) featuring a comprehensive set of prostatic needle biopsies as virtual slides, which can be viewed with a standard Web browser (Internet Explorer or Netscape). To evaluate the validity of Web-based virtual microscopy for Gleason grading, an experienced uropathologist (TK) scored a series of 62 biopsies from the original glass slides and 6 weeks later from virtual slides on the Web site using an ordinary desktop computer. The intraobserver agreement was excellent, with identical Gleason scores found in 48 of the 62 cases ( kappa = 0.73). The 14 remaining scores differed only by 1 point on the Gleason scale (2-10). The virtual slides were viewed by 2 other uropathologists (PM and HH), with interobserver kappa coefficients ranging from 0.55 to 0.62, which is within the range of previously reported studies using glass slides. The 3 uropathologists' Gleason scores were included as reference scores on the Web site, which now serves as a publicly open platform for self-testing and learning of Gleason grading. We conclude that Web-based virtual microscopy is a promising new tool for teaching and standardizing Gleason grading.  相似文献   
27.
Lymphocyte infiltrate is a hallmark of inflammatory responses. We have previously shown that de novo-induced endothelial sialyl Lewis x (sLex) expression guides lymphocytes in an L-selectin-dependent manner to sites of acute organ transplant rejections. In this research, we have analyzed five groups of chronic lung inflammations to determine the presence of properly glycosylated, i.e., sulfated, sLex-decorated, L-selectin ligands. Two anti-sLex (2F3 and HECA-452) and one anti-6- and/or 6'-sulfated and/or 6,6'-bisulfated (MECA-79) monoclonal antibodies (mAbs) were used. The control lung specimens did not express L-selectin ligands on endothelium. In contrast, the endothelial staining intensity and the number of positive peribronchial venules and capillaries with mAbs 2F3, HECA-452, and MECA-79 were significantly greater in bronchial biopsies from patients with asthma compared with normal specimens (P<0.003). However, no significant increase of peribronchial endothelial reactivity with these antibodies was observed in adult respiratory distress syndrome, chronic bronchitis, fibrosing alveolitis, and granulomatous inflammation compared with controls. These data suggest that sulfated sLex glycans, acting putatively as ligands for L-selectin, could be instrumental in lymphocyte extravasation into human peribronchial lung tissue during asthma, but not so important in several other inflammatory lung diseases.  相似文献   
28.
Eight human myeloma proteins, two of each IgG subclass, were studied for binding to solid-phase C3c and C3d by the ELISA technique. Myeloma IgG1κ, IgG1λ, IgG3κ and IgG3λ proteins bound to C3c and C3d, while two IgG2κ, and two IgG4κ proteins failed to show significant binding affinity. The results suggest that like C1q, the stable binding sites of C3, located on the C3c and C3d parts of the molecule, have affinity for IgG subclasses 1 and 3.  相似文献   
29.
Retinoblastoma family proteins pRb, p107 and p130 are differentially expressed in the rat testis. They function in specific cell types during testicular development and spermatogenesis, participating in the control of proliferation, differentiation, and survival. Their expression levels and phosphorylation status are modulated during germ cell cycle progression and apoptosis. Hyperphosphorylated states and elevated levels of p107 are correlated with cell cycle progression, whereas hypophosphorylated states and reduced levels are associated with suppression of proliferation and apoptosis in germ cells and Leydig cells. These proteins may also serve as markers of cell cycle status of germ cells during spermatogenesis.  相似文献   
30.
OBJECTIVE: Ospemifene, a novel selective estrogen receptor modulator (SERM), shows promise for bone preservation in postmenopausal women. This study examined the effects of ospemifene on different vascular surrogate markers. DESIGN: A double-blinded study was conducted in 160 healthy, postmenopausal women who used, in a randomized order, ospemifene (at daily doses of 30, 60, or 90 mg) or placebo for 3 months. RESULTS: Although ospemifene caused falls from basal levels in total cholesterol, low-density lipoprotein cholesterol, oxidized low-density lipoprotein cholesterol, and a rise in high-density lipoprotein cholesterol, the only statistically significant difference between ospemifene and placebo was an increase of triglyceride levels (11.3%) in the 90-mg group. Ospemifene caused no significant effect on endothelial markers or homocysteine. Of the markers reflecting coagulation and fibrinolysis, plasma fibrinogen was significantly reduced in the 60- and 90-mg groups of ospemifene (8.7% and 8.5%, respectively) when compared with the placebo group. No changes were seen in generation of thrombin or degradation of crosslinked fibrin D-dimer. The uterine or carotid arteries and 24-h ambulatory blood pressure were not affected by ospemifene. Ospemifene caused no changes in basal insulin or in a 2-h glucose tolerance test, suggesting unaltered insulin sensitivity. CONCLUSIONS: Neutral effects of short-term use of ospemifene on vascular surrogate markers imply no effect for ospemifene on the risk for cardiovascular disorders in healthy, postmenopausal women.  相似文献   
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