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91.
A phage-display technology was used to produce a single-chain Fv antibody fragment (scFv) from the 30AA5 hybridoma secreting anti-glycoprotein monoclonal antibody (MAb) that neutralizes rabies virus. ScFv was constructed and then cloned for expression as a protein fusion with the g3p minor coat protein of filamentous phage. The display of antibody fragment on the phage surface allows its selection by affinity using an enzyme-linked immunosorbent assay (ELISA); the selected scFv fragment was produced in a soluble form secreted by E. coli. The DNA fragment was sequenced to define the germline gene family and the amino-acid subgroups of the heavy (VH) and light (VL) chain variable regions. The specificity characteristics and neutralization capacity of phage-displayed and soluble scFv fragments were found to be identical to those of the parental 30AA5 MAb directed against antigenic site II of rabies glycoprotein. Phage-display technology allows the production of new antibody molecule forms able to neutralize the rabies virus specifically. The next step could be to engineer and produce multivalent and multispecific neutralizing antibody fragments. A cocktail of multispecific neutralizing antibodies could contain monovalent, bivalent or tetravalent scFv fragments, for passive immunoglobulin therapy.  相似文献   
92.
The concentrations of the soluble adhesion molecules E-cadherin, E-selectin, intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were investigated in 48 patients with colorectal cancer before treatment, and their relation to clinical, histological and routine laboratory parameters was examined. Data were collected on tumour stage at presentation, presence and sites of metastatic disease, tumour pathology and results of routine laboratory tests. Serum concentrations of ICAM-1 and VCAM-1 were significantly elevated in the patients with colorectal cancer in comparison with a group of healthy subjects (P < 0.00001). Levels of circulating ICAM-1 and VCAM-1 were increased both in patients with local and those with metastatic disease. Although elevated in some patients soluble E-cadherin and E-selectin concentrations were not significantly elevated compared with the control group (P = 0.71 and P = 0.052 respectively). The levels of circulating ICAM-1 were significantly correlated with those of VCAM-1 and E-selectin. A correlation was also found between the serum concentrations of E-selectin and ICAM-1 and alkaline phosphatase, total white cell count and platelet count. VCAM-1 was positively correlated with age and negatively with degree of tumour differentiation and haemoglobin concentration. The biological implications and possible clinical relevance of these findings are discussed.  相似文献   
93.
GM1 gangliosidosis is an inherited metabolic disease characterized by progressive neurological deterioration with premature death seen in children and numerous animals, including cats. We have observed that thymuses from affected cats greater than seven months of age (GM1 mutant cats) show marked thymic reduction compared to age-matched normal cats. The studies reported here were done to describe alterations in the thymus prior to (less then 90 days of age) and during the development of mild (90 to 210 days of age) to severe (greater than 210 days of age) progressive neurologic disease and to explore the pathogenesis of the thymic abnormality. Although histologic examination of the thymus from GM1 affected cats less than 210 days of age showed no significant differences from age-matched control cats, thymuses from GM1 mutant cats greater than 210 days of age were significantly reduced in size (approximately 3-fold). Histologic sections of lymph nodes, adrenal glands, and spleens from GM1 gangliosidosis-affected cats showed no significant differences. Flow cytometric analyses showed a marked decrease in the percentage of immature CD4+CD8+ thymocytes (p < 0.001) and significantly increased CD4-CD8+ cells (p < 0.01) in GM1 mutant cats greater than 210 days of age when compared to normal age matched cats. Co-labelling with CD4, CD8, and CD5 indicated an increase in the percentage of GM1 mutant cat thymocytes at this age which were CD5high, suggesting the presence of more mature cells. Cytometric analyses of subpopulations of peripheral lymphocytes indicated an increase in CD4-CD8+ cells (p < 0.05) with concurrent decreases in CD4+CD8- and CD4-CD8- cells (which were not significant). Similar analyses of thymocyte and lymphocyte subpopulations from cats < 210 days of age showed no significant differences between GM1 mutant and normal cells. GM1 mutant cats at all ages had increased surface binding of Cholera toxin B on thymocytes, indicating increased surface GM1 ganglioside expression. Increases were highly significant in GM1 mutant cats greater than 210 days of age. In situ labelling for apoptosis was increased in GM1 mutant cats between 90 to 200 days of age when thymic masses were within normal limits. In GM1 mutant cats over 200 days of age, decreased labelling was observed when thymic mass was reduced and the CD4+CD8+ subpopulation, known to be very susceptible to apoptosis, was significantly decreased. These data describe premature thymic involution in feline GM1 gangliosidosis and suggest that increased surface GM1 gangliosides alters thymocyte development in these cats.  相似文献   
94.
The role of beta3- and other putative atypical beta-adrenoceptors in human white adipocytes and right atrial appendage has been investigated using CGP 12177 and novel phenylethanolamine and aryloxypropanolamine beta3-adrenoceptor (beta3AR) agonists with varying intrinsic activities and selectivities for human cloned betaAR subtypes. The ability to demonstrate beta1/2AR antagonist-insensitive (beta3 or other atypical betaAR-mediated) responses to CGP 12177 was critically dependent on the albumin batch used to prepare and incubate the adipocytes. Four aryloxypropanolamine selective beta3AR agonists (SB-226552, SB-229432, SB-236923, SB-246982) consistently elicited beta1/2AR antagonist-insensitive lipolysis. However, a phenylethanolamine (SB-220646) that was a selective full beta3AR agonist elicited full lipolytic and inotropic responses that were sensitive to beta1/2AR antagonism, despite it having very low efficacies at cloned beta1- and beta2ARs. A component of the response to another phenylethanolamine selective beta3AR agonist (SB-215691) was insensitive to beta1/2AR antagonism in some experiments. Because no [corrected] novel aryloxypropanolamine had a beta1/2AR antagonist-insensitive inotropic effect, these results establish more firmly that beta3ARs mediate lipolysis in human white adipocytes, and suggest that putative 'beta4ARs' mediate inotropic responses to CGP 12177. The results also illustrate the difficulty of predicting from studies on cloned betaARs which betaARs will mediate responses to agonists in tissues that have a high number of beta1- and beta2ARs or a low number of beta3ARs.  相似文献   
95.
PURPOSE: To determine the frequency of remission in patients with essential blepharospasm and Meige syndrome. METHOD: Retrospective analysis of patients by means of questionnaire in an institutional setting. RESULTS: Among 238 patients diagnosed in a single institution as having essential blepharospasm or Meige syndrome, 27 (11.3%) claimed to be symptom free without curative surgery. The average time between onset and resolution in the patients who claimed remission was 4.85 years (range, 3 months to 22 years). Among these patients, the duration of remission averaged 6.33 years (range, 1 year to 14 years). CONCLUSION: Patients with essential blepharospasm or Meige syndrome have a small but definite potential for spontaneous remission of symptoms, particularly within the first 5 years after onset of symptoms.  相似文献   
96.
97.
Treatments of Chinese hamster V79 cells during one cell cycle with a new type of topoisomerase II inhibitor, ICRF-193, which does not accumulate cleavable topoisomerase-DNA complexes induced both chromosome- and chromatid-type aberrations with high frequencies. Furthermore, ICRF-193 synergistically enhanced the yield of UVB-induced chromatid-type aberrations, chromatid exchanges in particular. Treated with ICRF-193 for the last 3 h before harvest, cells showed frequent incidence of chromatid-type aberrations and synergistic enhancement of UVB-induced chromatid-type aberrations, chromatid exchanges in particular. These results suggest that spontaneous and UVB-induced lesions might be ultimately transformed into chromatid-type aberrations by topoisomerase II-dependent checkpoint process(es) in the G2 phase of the cell cycle.  相似文献   
98.
Antemortem serum and postmortem serum and tissues were evaluated to determine if postmortem redistribution of the antidepressant, fluoxetine (Prozac) and its major active metabolite, norfluoxetine, occurred in dogs following oral administration of fluoxetine hydrochloride. Beagle dogs (four males) received daily oral doses of 10 mg fluoxetine/kg for five days. Antemortem serum concentrations of fluoxetine and norfluoxetine were determined 3 and 24 h following administration of the first four daily doses of fluoxetine and 3 h after the fifth dose in order to monitor for steady-state serum concentrations of parent and metabolite prior to postmortem serum concentration determinations. Antemortem serum concentrations of fluoxetine and norfluoxetine 3 h postdose on Day 5 ranged from 530 to 1210 ng/mL and 1460 to 1980 ng/ mL, respectively. Immediately following the 3 h blood sample on Day 5, each dog was euthanized. Serum concentrations of fluoxetine and norfluoxetine were determined from blood samples collected from the vena cava, heart, and clotted blood within the heart at 2 h after death in two dogs and 12 h after death in the remaining two dogs. Similarly, tissue concentrations of fluoxetine and norfluoxetine in heart, liver, and lung were determined 2 and 12 h postmortem. Serum concentrations of fluoxetine and norfluoxetine from the vena cava and heart 2 h postmortem were 2.2- to 6.0-fold and 2.3- to 3.6-fold higher, respectively, than antemortem serum concentrations. Similarly, serum concentrations of fluoxetine and norfluoxetine from vena cava and heart 12 h postmortem were 1.3- to 3.5-fold and 1.7- to 3.3-fold higher, respectively, than antemortem serum concentrations. However, 2-h and 12-h postmortem serum concentrations of fluoxetine and norfluoxetine from clotted blood within the heart were equal to or less than levels determined in antemortem serum. Results from 2-h and 12-h postmortem average tissue concentrations of fluoxetine and norfluoxetine in heart, liver, and lung demonstrated that fluoxetine and norfluoxetine concentrations in myocardium were similar 2 h and 12 h postmortem. However, in liver, fluoxetine concentrations decreased 39% and norfluoxetine concentrations decreased 23% from 2 h to 12 h postmortem. Even greater postmortem decreases in fluoxetine and norfluoxetine concentrations were observed in lung. Fluoxetine and norfluoxetine concentrations in lung decreased 49% and 39%, respectively, from 2 h to 12 h postmortem. In conclusion, this study demonstrated that fluoxetine and norfluoxetine undergo postmortem redistribution in the dog. Furthermore, postmortem serum concentrations appear to be dependent on the sample site and the degree of coagulation of the blood. Finally, postmortem decreases in concentrations of fluoxetine and norfluoxetine in liver and lung may, in part, explain the observed increase in serum concentrations at 2 and 12 h postmortem.  相似文献   
99.
100.
The two temperature-sensitive (ts) lesions present in influenza A/Hong Kong/68-ts-1[E] (H3N2 68) virus were transferred via genetic reassortment to influenza A/Georgia/74 (H3N2 74) wild-type virus. A recombinant clone possessing both ts lesions and the shutoff temperature of 38 C of the Hong Kong/68 ts donor and the two surface antigens of the Georgia/74 wild-type virus was administered to 32 seronegative adult volunteers. Thirty-one volunteers were infected, of whom only five experienced mild afebrile upper respiratory tract illness. The wild-type recipient virus was a cloned population that induced illness in five of six infected volunteers. Therfore, the attenuation exhibited by the Georgia/74-ts-1[E] virus could reasonably be assumed to be due to the acquisition of the two ts-1[E] lesions by the Georgia/74 wild-type virus. The serum and nasal wash antibody responses of the ts-1[E] vaccinees were equivalent to those of the volunteers who received wild-type virus. The two ts lesions present in the Hong Kong/68-ts-1[E] virus have now been transferred three times to a wild-type virus bearing a new hemagglutinin, and in each instance the new ts recombination exhibited a similar, satisfactory level of attenuation and antigenicity for adults. It seems likely that the transfer of the ts-1[E] lesions to any new influenza virus will regularly result in attenuation of a recombinat virus possessing the new surface antigens.  相似文献   
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