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Biomedical subjects

S Pal

Publications and source records attributed to S Pal.

At least 127 records · Page 7Linked to original sources

Effect of nerve growth factor and forskolin on glycosyltransferase activities and expression of a globo-series glycosphingolipid in PC12D pheochromocytoma cells.

The glycosphingolipid (GSL) composition of cells changes dramatically during cellular differentiation. Nerve growth factor (NGF) or forskolin (FRK) are known to induce cellular differentiation including process formation in PC12 pheochromocytoma cells. In this respect, we present the NGF/FRK-dependent regulation of glycosyltransferase activities and the corresponding GSL expression in PC12D cells. After treatment of PC12D cells with NGF or FRK, the cell processes, including varicoses and growth cones, became strongly immunoreactive with an antibody against a unique globo-series neutral GSL, Gal alpha 1-3Gal alpha 1-4Gal beta 1-4Glc beta 1-1'Cer (GalGb3), and the activity of GalGb3-synthase increased significantly. Other glycosyltransferase activities, including GM1 containing blood group B determinant (BGM1)-, GM3-, GD1a-, and GM2-synthases, also increased significantly upon NGF treatment, but the immunoreactivity against BGM1 did not show any appreciable change. For the parent PC12 cells, NGF/FRK treatment significantly increased the percentage of anti-GalGb3 positive cells and induced some immunoreactive cell processes. Because the parent PC12 cells do not express appreciable amounts of GalGb3, and because PC12D cells are considered to be more differentiated than the parent PC12 cells, the expression of GalGb3 and the increase of GalGb3-synthase activity may be closely related to the cellular differentiation process in this cell line.

Animals↗

Historical introduction of acupuncture in India.

Acupuncture, though originated in oriental countries in the ancient times but, its philosophical understanding is amazingly wide open to the modern medical science. Historically, records are there regarding its Indian origin. However, acupuncture practised today in Indian sub-continent mainly shows Chinese origin and its introduction to India was pioneered by Dr. B.K. Basu, the first Indian who learned Chinese acupuncture from mainland China during 1959. It is interesting enough to note that though acupuncture is successfully practised in India in a rejuvenated form for the last few decades but due to lack of proper Governmental support this thereby suffers from under utilization and under development. While WHO suggested for its wider application and development through concerted Governmental efforts.

Acupuncture Therapy↗

Survivability and leucocyte migration inhibition in mice immunized with cryotreated ascites fibrosarcoma cells using different freeze-thaw cycles.

Attempts have been made to assess as to what extent in vitro assay of cellular immunity, e.g. leucocyte migration inhibition (LMI) in mice immunized with different freeze-thaw cycles could reflect host resistance in vivo. While survivability of animals improved significantly by immunization with single cycle (P < 0.05) to three cycle (P < 0.001) and programmed three cycle (P < 0.001) cryo-treated tumor cells compared to controls, the percentage LMI in the same groups of animals decreased progressively. The KCl(3M) extracted tumor cell protein (antigen) of both viable and cryo-treated cells showed a progressively increased protein concentrations per 1 x 10(6) tumor cells with viable cells being least and programmed three cycle cryo-treated cells highest. The apparent discrepancy observed between percentage migration inhibition and survivability may be due to the fact that (1) survivability is a function of body's total immune response while LMI represents the response of one effector limb only; (2) immuno-regulatory mechanisms depend on a balance between activation and suppression and suppressor cells being more sensitive and of shorter life span, affect migration inhibition but not the survivability; (3) cryo-treatment alters tumor cell surface antigen affecting immunological balance; and (4) suppressor and antitumor activities against antigenic stimulation develop simultaneously in different organs and LMI performed with sensitized splenic cells, where, perhaps, suppressor cell activity dominates.

Animals↗

Haemagglutinating property & cell surface hydrophobicity of Vibrio cholerae 0139.

Cell-associated haemagglutinating activity was detected in all the epidemic strains of V. cholerae 0139 and 01, isolated in different parts of the country, with erythrocytes from rabbit, rat, chicken and guinea pig. Sheep erythrocytes were unresponsive to both groups of strains. While D-mannose, alpha-methyl-D-mannoside, glucosamine, N-acetyl-D-glucosamine, thyroglobuline were effective inhibitors of the haemagglutinating activity of the V. cholerae 0139 and 01 strains, galactose and N-acetyl-D-galactosamine sensitive haemagglutinins (HAs) were detected in the V. cholerae 01 but not in the V. cholerae 0139 strains. The best medium for expression of HAs in V. cholerae 01 and 0139 strains were observed to be penassay broth and tryptic soy broth respectively. The expression of HA in V. cholerae 01 was stimulated by Ca++ and Fe in the growth medium unlike that of V. cholerae 0139 which remained unaffected by these ions.

Animals↗

A chlamydial major outer membrane protein extract as a trachoma vaccine candidate.

PURPOSE: As shown in infected humans and in animal models of chlamydial infection, the major outer membrane protein (MOMP) of Chlamydia trachomatis is immunogenically potent. The purpose of this investigation was to test in the cynomolgus monkey model of trachoma a new extract of MOMP as a candidate vaccine against ocular chlamydial infection. METHOD: The nonionic detergent octyl-beta-D glucopyranoside (OGP) was used to extract MOMP from purified C. trachomatis (serovar C) elementary bodies. Protective immunization with OGP-MOMP by mucosal and systemic routes was compared in the cynomolgus monkey model of trachoma. All control and immunized monkeys were challenged by topical application of infectious C. trachomatis to the conjunctivae 35 days after the initiation of immunization. RESULTS: Immunization with OGP-extracted MOMP successfully induced chlamydia-specific local and systemic immunity to MOMP and to whole organism before challenge and early clearance of infection by systemically immunized monkeys. Although ocular disease was not significantly reduced in either immunized group compared to control animals, the lowest clinical and microbiologic disease scores developed in two animals in the mucosal group with the highest immunoglobulin A tear antibody titers at day 0 to 14, whereas higher tear and serum immunoglobulin G correlated with reduced disease in the systemically immunized group. CONCLUSIONS: These data demonstrate that despite evidence of vigorous MOMP-specific and other chlamydia-specific serologic and cell-mediated immunity, as well as anamnestic serologic responses to chlamydia, vaccination with OGP-MOMP was only partially protective against chlamydial ocular disease. The partial protection correlated best with tear immunoglobulin A responses after mucosal immunization and with local and systemic immunoglobulin G responses after peripheral immunization, suggesting that alternative chlamydial antigens may have to be considered in future vaccine development to induce more effective protective immunity and that evaluation of efficacy must be appropriate to route of immunization.

Administration, Oral↗

Immunological parameters in leprosy patients with and without arthritis.

Twelve patients of leprosy with arthritis and 161 patients without arthritis were studied for immunological parameters like immunoglobulins (IgG, IgM, IgA), C-reactive proteins and rheumatoid factor. There was increase in the levels of IgG, IgA value in leprosy patients with and without arthritis compared to healthy control. IgM level was decreased in both the groups compared to control, but significant decrease was observed (p < .01) in patients with arthritis. C-reactive protein was significantly positive in leprosy with arthritis group (p < .01) and positive in 12 cases of leprosy without arthritis group compared to negative control group. Rheumatoid factor was present in leprosy with arthritis (16.6%) compared to both the control group and leprosy without arthritis group. This study concluded the presence of arthritis in leprosy patients as a definite entity which showed changes in immunological parameters.

Adult↗

Anti-tumor efficacy of glutaminase-copper-ATP combination in mice bearing Ehrlich ascites carcinoma.

Glutaminase is a hematotoxic anti-tumor agent, and copper-ATP complex (Cu-ATP) is both anti-neoplastic and hematostimulatory. Combination chemotherapy with these two agents has been performed in mice bearing Ehrlich ascites carcinoma, to elucidate whether this could result in augmented tumor inhibition with reduced hematotoxicity. Glutaminase-Cu-ATP combination (glutaminase 250 IU/kg per day intraperitoneally for 10 days and Cu-ATP 2.5 mg/kg per day intraperitoneally for 10 days) was observed to be more effective in inhibiting tumor growth and in increasing the life span of the tumor hosts, compared with the individual efficacies of these two agents. Moreover, addition of Cu-ATP successfully prevented the hematotoxic effects of glutaminase in normal and in tumor-bearing animals. Thus glutaminase in combination with Cu-ATP holds promise for an effective cancer chemotherapeutic regimen.

Adenosine Triphosphate↗

Intravaginal inoculation of mice with the Chlamydia trachomatis mouse pneumonitis biovar results in infertility.

In an attempt to establish a model of chlamydial ascending salpingitis and infertility, three inbred strains of mice, C3H/HeN (H-2k), C57BL/6N (H-2b), and BALB/cAnN (H-2d), were inoculated intravaginally with 3 x 10(7) inclusion-forming units of the Chlamydia trachomatis mouse pneumonitis biovar. Mice mated 6 weeks following inoculation were found to have a significant decrease in fertility rate compared with the control groups, as shown by a reduction in the number of pregnant mice and a decrease in the number of embryos.

Animals↗

Protection against infertility in a BALB/c mouse salpingitis model by intranasal immunization with the mouse pneumonitis biovar of Chlamydia trachomatis.

Female BALB/c mice were immunized intranasally with the mouse pneumonitis biovar of Chlamydia trachomatis and subsequently challenged in the ovarian bursa (C. trachomatis immunized, C. trachomatis challenged). Two groups of mice served as controls. One group was sham immunized intranasally with mock-infected HeLa 229 cell extracts and was challenged in the ovarian bursa with C. trachomatis MoPn (sham immunized, C. trachomatis challenged). The second control group was sham immunized and not challenged (sham immunized, nonchallenged). Before challenge, the C. trachomatis-immunized, C. trachomatis-challenged animals mounted a significant humoral response as shown by high immunoglobulin G (IgG), IgM, and IgA levels and high levels of neutralizing antibodies in serum and moderate IgG and IgA titers in vaginal secretions. Reactivity by Western blot (immunoblot) to the lipopolysaccharide, 30-, 40- (major outer membrane protein), and 60-kDa cysteine-rich proteins and 75- and 100-kDa chlamydial components could be demonstrated. However, reactivity to the 60-kDa heat shock protein was only observed 22 days after challenge. In addition, this group of animals mounted a significant immune response to chlamydial antigens, as shown by a lymphocyte proliferation assay, compared with the sham-immunized nonchallenged mice. After intrabursal challenge, there was no C. trachomatis shedding from the vagina in the C. trachomatis-immunized, C. trachomatis-challenged animals, while 63% of the sham-immunized, C. trachomatis-challenged mice had a positive C. trachomatis culture. In addition, histological sections from the genital tract showed, at 2 weeks postchallenge, a marked acute inflammatory reaction in the sham-immunized, C. trachomatis-challenged animals while in the C. trachomatis-immunized, C. trachomatis-challenged mice there was minimal inflammatory reaction. When the animals were mated, only 12% of the mice from the sham-immunized, C. trachomatis-challenged mice were fertile. In contrast, 94 and 80% of the sham-immunized, nonchallenged and C. trachomatis-immunized, C. trachomatis-challenged mice, respectively, were fertile.

Administration, Intranasal↗

Efficient copying of nonhomologous sequences from ectopic sites via P-element-induced gap repair.

P-element-induced gap repair was used to copy nonhomologous DNA into the Drosophila white locus. We found that nearly 8,000 bp of nonhomologous sequence could be copied from an ectopic template at essentially the same rate as a single-base substitution at the same location. An in vitro-constructed deletion was also copied into white at high frequencies. This procedure can be applied to the study of gene expression in Drosophila melanogaster, especially for genes too large to be manipulated in other ways. We also observed several types of more complex events in which the copied template sequences were rearranged such that the breakpoints occurred at direct duplications. Most of these can be explained by a model of double strand break repair in which each terminus of the break invades a template independently and serves as a primer for DNA synthesis from it, yielding two overlapping single-stranded sequences. These single strands then pair, and synthesis is completed by each using the other as a template. This synthesis-dependent strand annealing (SDSA) model as a possible general mechanism in complex organisms is discussed.

Animals↗

Induction of infertility by the Chlamydia trachomatis mouse pneumonitis biovar in strains of mice that differ in their response to the 60 kDa heat shock protein.

To determine the role that the host response to the chlamydial 60 kDa heat shock protein (hsp) plays in the pathogenesis of infertility, C3H/HeN (H-2k) and C57BL/6 (H-2b) mice were inoculated in the left ovarian bursa with 1 x 10(5) inclusion forming units of the Chlamydia trachomatis mouse pneumonitis (MoPn) biovar, and in the right ovarian bursa with mock-infected HeLa-229 cell extracts. Control mice were inoculated with mock-infected HeLa-229 cell extracts. These two strains of mice were chosen because the C3H mice mount a strong immune response to the 60 kDa hsp, whereas the C57BL/6 mice respond only weakly. Vaginal cultures obtained after inoculation were positive for 4 weeks in both strains of mice. Histological sections showed a marked acute inflammatory infiltrate that permeated all the layers of the oviduct and lasted for approximately 2 weeks in both strains. By the third week, mononuclear inflammatory cells were also observed and from 4 weeks after inoculation, hydrosalpinx formation was observed, particularly in the C3H mice. An inclusion immunofluorescence assay detected antibodies specific for chlamydia in the serum and the vaginal washes of the C3H and C57BL/6 mice. Western blot analysis of the serum samples showed an immune response to lipopolysaccharide, and the 30, 40 (major outer membrane protein) and 60 kDa cysteine-rich protein in both strains of mice. In addition, in the C3H mice a strong immune reaction was mounted against a 50 kDa component and the 60 kDa hsp. Six weeks after inoculation, the female mice were mated with male mice of proven fertility and the outcome of the pregnancies evaluated.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗