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51.
Kelly K. Hunt Masahiko Shibata Rishab K. Gupta Donald L. Morton 《Cancer immunology, immunotherapy : CII》1992,34(6):377-382
Summary We developed a high-titer polyclonal antiserum to a glycoprotein tumor-associated antigen (TAA) by immunization of a baboon with the purified glycoprotein antigen. The baboon serum was fractionated into IgG and IgM components by DEAE Affi-Gel blue chromatography. The ability of the baboon IgM anti-TAA antibody to effect tumor cell lysis in the presence of complement was tested using a chromium-release assay. The baboon antibody was able to lyse melanoma target cells (20.8%–71.4% cytolysis), breast carcinoma cells (36.5%–38.9% cytolysis), and a neuroblastoma cell line (35.5% cytolysis) in the presence of complement but did not effect significant lysis of autologous lymphoblastoid cell lines (4.9% cytolysis) or peripheral blood lymphocytes from healthy volunteers (12.6% cytolysis). Cytolysis of melanoma target cells was completely inhibited by preabsorption of the IgM anti-TAA antibody with UCLA-SO-M14 (M14) cells and partially inhibited by preabsorption with several other melanoma cell lines. There was no significant inhibition of tumor cell lysis after preabsorption of the antibody with lymphoblastoid cell lines. Complement-dependent lysis of M14 targets could be blocked by addition of the purified antigen to the antibody prior to incubation with the tumor cells. Our results suggest that the glycoprotein TAA resides on the tumor cell surface and that the baboon IgM anti-TAA antibody recognizes the antigen on the cell surface and is able to fix complement and effect the lysis of the tumor cells. 相似文献
52.
K. C. Malhotra T. S. Vasulu Y. S. Dikshitulu R. C. Gupta 《International Journal of Anthropology》1992,7(1):23-40
An attempt was made to investigate dermatoglyphic variation between four sex-crimes (SC) and four sex and other crime (SOC) convicts. These were compared with 10 endogamous and 11 penal populations. The results indicate that the two closely related sex crime cases IPC-363 and IPC 366 («kidnap» and «abducting») show wide differences in dermatoglyphic characters. A comparison of sex crimes with sex and other crime cases showed least differences in the case of IPC-363, IPC-363 KC and in IPC 366 and IPC-366 AC but wide differences in IPC-354 («molestation») cases. The dendrograms suggest that the eight sex crime cases cluster together and are different from other endogamous and penal populations. The significant low mean finger ridge count observed in the case of IPC-366 is in agreement with other studies, suggesting a strong association between crime (sex) and dermatoglyphics. 相似文献
53.
A M Deffie J P McPherson R S Gupta D W Hedley G J Goldenberg 《Biochimie et biologie cellulaire》1992,70(5):354-364
54.
Flavonoid glycosides from Cassia alata. 总被引:1,自引:0,他引:1
Two new glycosides, chrysoeriol-7-O-(2"-O-beta-D-mannopyranosyl)-beta-D-allopyranos ide and rhamnetin-3-O-(2"-O-beta-D-mannopyranosyl)-beta-D-allopyranosid e, were isolated from the seeds of Cassia alata. The structures were established on the basis of chemical evidence and spectroscopic methods, especially NMR. 相似文献
55.
P Lemansky D K Gupta S Meyale G Tucker A M Tartakoff 《Molecular and cellular biology》1991,11(8):3879-3885
Essentially all eukaryotic cells, including murine lymphomas, express surface proteins, such as Thy-1, which are anchored by a phosphoinositol mannolipid. Putative mannolipid anchor precursors can be detected in these cells. Six distinct Thy-1-negative lymphoma mutants lack complete mannolipids, and three mutants synthesize atypical mannolipids. The absence of complete mannolipids can account for the lack of expression of multiple mannolipid-anchored proteins and may also account for the lack of lipid anchoring in the human disease paroxysmal nocturnal hemoglobinuria. Structural information on the mannolipids of wild-type and mutant cells indicates that anchor biosynthesis in these cells may involve both transmembrane flip-flop of intermediates and a deacylation step. 相似文献
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1988. Homosexual male pairing in Schistosoma mansoni.International Journal for Parasitology 18: 1115–1117. To see whether male worms within the gynecophoral canal of another male worm would become feminized (i.e. express vestigial female-associated genes), we established homosexual pairs by twice exposing mice to male cercariae with a 4 or 6-week interval, and perfusing 3–5 weeks later. From 13 to 34% of these worms were found in pairs, compared with 0 to 7% in singly exposed controls. ‘Inner’ males in homosexual pairs showed no histological evidence of female reproductive structures, but were stunted, had poorly developed testes, and the high nuclear density characteristic of mature females. More vitelline follicles occurred in unpaired unisexual males than in homosexually paired males, fewest in bisexually paired males. Uptake of tyrosine, an indicator of vitelline development, occurred in the same relative order. The gynecophoral microenvironment often led to stunting, probably through starvation induced by the relative inaccessibility of host blood to homosexually clasped males. 相似文献
59.
Immunocytochemical localization of hexosaminidase activity in human males revealed that the enzyme activity is localized mainly in the Sertoli cells and interstitial tissue of the testis and in the columnar cells of the epididymis. In seminal vesicles, activity was observed around the glandular epithelium in the form of fine granules. 相似文献
60.
Studies on the interaction of anesthetic steroids with phosphatidylcholine using 2H and 13C solid state NMR 总被引:1,自引:0,他引:1
A Makriyannis D J Siminovitch S K Das Gupta R G Griffin 《Biochimica et biophysica acta》1986,859(1):49-55
The effects of the anesthetic steroid alphaxalone and its inactive analog delta 16-alphaxalone on model phospholipid membranes were studied using 13C and 2H solid-state nuclear magnetic resonance spectroscopy. Aqueous multilamellar dispersions of dipalmitoylphosphatidylcholine (DPPC) with specific 13C and 2H labels as endogenous probes at the carbonyl and the C-7 methylene groups, respectively, of the sn-2 chain were used to study the conformational and dynamical properties of the bilayer as a function of temperature. There were no significant changes between the 13C and 2H spectra of the DPPC preparation containing the inactive steroid and that of DPPC with no drug. However, the physiologically active steroid produces significant spectral 2H and 13C changes. These changes include a reduction of the main phase transition temperature and a broadening of that transition. Alphaxalone also increases the relative number of gauche conformers in the liquid-crystalline phase of DPPC and increases the rate of axial diffusion in both the gel and liquid-crystalline phase. The thermotropic properties of the above preparations, as monitored by differential scanning calorimetry, were congruent with the spectroscopic data. 相似文献