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Biomedical subjects

S K Roy

Publications and source records attributed to S K Roy.

At least 145 records · Page 8Linked to original sources
PubMed1989

Effect of clomiphene on nuclear estrogen receptor of the fallopian tube during ovum transport in rabbits.

The effect of clomiphene on nuclear estrogen receptors of the Fallopian tube during ovum transport in the rabbit has been studied. Nuclear binding capacity was observed in ampulla (A), ampullary-isthmic junction (AIJ), isthmus (I), uterine-isthmic junction (UIJ) and uterus (U). Receptor concentration decreased in all segments of the tube after administration of clomiphene in mated animals. The bindings are of high affinity and low capacity. Important alterations were observed during transport when compared to that of 14, 24, 34, 48, 72, 144 and 168 hr post-coitum (p.c). At 24 hr p.c binding increased only in I and decreased in A and AIJ. Retention of eggs at I at 24 hr p.c showed as increase in binding at I. Egg transport was accelerated and eggs reached prematurely in the uterus due to the influence of clomiphene. Binding in I remained constant from 48 hr p.c to 144 hr p.c but concurrently the binding level increased in U from 34 hr p.c. The elevation of nuclear estrogen receptor level was maximum at 24 hr p.c which coincided with increased plasma estrogen level. The result of such study showed that clomiphene depleted nuclear estrogen receptor complex in the fallopian tube before transfer to the uterus. Further, observation indicated that clomiphene acted directly on the rate of egg transport because of the variations in estrogen receptors during different time periods. Thus, clomiphene reduced the quantity of estrogen receptor i.e., insensitiveness to estrogen. The variations in estrogen binding to its receptor and plasma level at different post-coital periods are modulated by clomiphene resulting in the acceleration of egg transport and prevention of pregnancy.

Animals↗
PubMed1988

Genetic studies among the sedentes and migrant Oraons of eastern India.

A total of 334 Oraons of both sexes from two localities in eastern India were tested for 11 polymorphic and six monomorphic blood genetic markers. The sample comprised 130 sedentes from the Gumla district in Bihar and 204 migrants to the Jalpaiguri district of North Bengal. At the hemoglobin locus one example of HbAS was observed in the Gumla sample, while two cases of HbAS were found in the Jalpaiguri group. The Oraons are a distinct tribe and are characterized by a very low frequency of Hp1, TFC2, and a high frequency of TfD1 and GcIF at the serum protein loci. In the red cell enzyme systems the Oraons have a higher frequency of pa at the acid phosphatase locus and GLO1 at the Glyoxalase I locus. Absence of red cell lactate dehydrogenase and very low HbS and GdB- is also characteristic of the Oraons. A probable new nondeficient slow variant of Gd has been observed in polymorphic frequency in the Oraons of Gumla. There was an excess of homozygotes at the Gc locus. No significant difference in the gene frequency between the two groups of Oraons was observed at any of the loci. Genetic distance estimates using the gene frequency data indicate that the Oraons of the two localities are genetically homogeneous and form one cluster with the Bhils. They are nearer to the Irula and Kurumba tribes of the Nilgiris rather than the other Dravidian tribes, Tamils, or Nayars.

Blood Proteins↗
PubMed1988

Induction and Catabolite Repression of beta-Glucosidase Synthesis in Myceliophthora thermophila D-14 (= ATCC 48104).

beta-Glucosidase activity in Myceliophthora thermophila D-14 (= ATCC 48104) was inducible and was produced in culture filtrate during growth with various inducers, of which PNPG (p-nitrophenyl-beta-d-glucoside) was the most efficient. Induction of beta-glucosidase also occurred when the organism was grown in medium supplemented with different carbon sources. Carboxymethyl cellulose, cellobiose, and Solka-Floc were found effective for induction of enzyme biosynthesis. The addition of glucose to the culture medium severely repressed beta-glucosidase synthesis, which could not be reversed by exogenous cyclic AMP or dibutyryl cyclic AMP.

Journal Article↗
PubMed1988

In vitro effects of follicle-stimulating hormone, luteinizing hormone, and prolactin on follicular deoxyribonucleic acid synthesis in the hamster.

Follicles were dissected by hand or enzymatically from the ovary of the proestrous hamster at 0900 h and classified into 10 stages: stages 1-4, follicles with 1-4 layers of granulosa cells and no theca; stages 5-8, preantral follicles with 5 or more layers of granulosa cells and theca to small antral follicles; stage 9, intermediate-sized atretic antral follicles; and stage 10, healthy preovulatory antral follicles. Follicles were then incubated for 2 h with [3H]thymidine [( 3H]Tdr) in the absence or presence of gonadotropins and with incorporation of radionuclide into DNA as the end point. FSH (25 ng) significantly stimulated [3H]Tdr incorporation in all stages of follicular development with a latency of 2 h, and this effect was inhibited by 2 micrograms unlabeled Tdr. While FSH and PRL (25 and 100 ng) stimulated [3H]Tdr incorporation in all stages, LH (0.2-5 ng) action began from stage 5 onward, when definitive thecal cells and LH receptors started appearing. LH (5 ng) also suppressed 25 ng FSH-induced DNA synthesis in stages 5-10; however, stages 1-4 were unaffected. Significant increases in both intra- and extracellular cAMP levels occurred in follicles at stages 2-10 after FSH administration. In contrast, LH was active in stages 5-10, whereas PRL was ineffective. Follicular DNA synthesis increased markedly when stimulated by 8-bromo-cAMP (0.01-2 mM). These results show that gonadotropins act directly as a primary stimulus at the level of small primary and secondary follicles to regulate DNA synthesis and, thus, perhaps the growth and differentiation of granulosa and thecal cells; cAMP functions as one of the possible intracellular mediators of gonadotropin action in initiating DNA replication.

1-Methyl-3-isobutylxanthine↗
PubMed1987

Effect of tamoxifen on cytosolic estrogen receptor in the different parts of fallopian tube and uterus during ovum transport.

The effect of tamoxifen (ICI-46474) (alpha-[4-(beta-N-dimethylamino ethoxy)-phenyl]alpha'-ethyl trans stilbene on estrogen cytosolic receptor was observed in different parts of fallopian tube and uterus of rabbits during ovum transport. Tubal segments viz. ampulla (A), ampullary isthmic junction (AIJ), isthmus (I), uterine isthmic junction (UIJ) and uterus (U) were studied during the passage of ovum. Significant differences were observed in normal, drug treated and pregnant animals at 14, 24, 34, 48, 72, 144 and 168 h. In treated animals during 14 h post-coitum (p.c.) to 34 h p.c. the ampullary cytosol receptor concentration increased and suddenly decreased at 48 h p.c. whereas from 72 h p.c. to 144 h p.c. it increased gradually. Tamoxifen accelerated the rate of egg transport decreasing tubal cytosolic receptors at 48 h p.c. However, beyond 48 h p.c. receptors increased till 144 h p.c. Results suggest that tamoxifen modulated tubal cytosolic estrogen receptors during egg transport and prevents pregnancy.

Animals↗
PubMed1987

In vitro steroidogenesis by primary to antral follicles in the hamster during the periovulatory period: effects of follicle-stimulating hormone, luteinizing hormone, and prolactin.

Hamster ovarian follicles at Stages 1 to 10 (Stages 1-4: follicles with 1-4 layers of granulosa cells (GC); Stages 5-7: 5-10 layers GC plus theca; Stages 8-10: antral follicles) were isolated on the morning of proestrus or estrus and incubated for 2 h in the absence or presence of follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (Prl), progesterone (P4), 17 alpha-hydroxyprogesterone (17OHP), or androstenedione (A). Steroid accumulations in the media were measured by radioimmunoassay (RIA). On proestrus, without any hormonal stimulus, consistent accumulation of P4 through estradiol-17 beta (E2) occurred in low amounts only from Stage 6 and on; both FSH (5-25 ng) and LH (1-25 ng) significantly stimulated steroidogenesis by Stage 6-10 follicles, and the effects of FSH, except for Stage 10, were largely attributable to LH contamination. However, 25 ng FSH significantly stimulated A production by Stages 1-4, whereas 1-25 ng LH was ineffective. On estrus, follicles at all stages, especially 1-6, showed significant and dose-dependent increases in P4 production in response to FSH; both FSH and LH significantly stimulated P4 and 17OHP accumulation from Stage 5 onwards; however, there was no increase in A and E2 compared to controls. Even the smallest estrous follicles showed a shift to predominance of P4 accumulation. On proestrus, Prl had a negative influence on LH-induced accumulation of P4 and 17OHP by Stages 7-9 and 6-8, respectively, without affecting A or E2.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1987

Radioreceptor and autoradiographic analysis of FSH, hCG and prolactin binding sites in primary to antral hamster follicles during the periovulatory period.

As measured by radioreceptor assays, binding sites for FSH and prolactin were present at 09:00 h on the day of pro-oestrus in Stage 1-10 follicles (primary to antral) with prolactin receptors 3-6 times higher than FSH sites in Stages 1-3 (3 layers of granulosa cells). Specific binding sites for hCG were present in Stage 1 and 2 follicles (2 layers of granulosa cells) but thereafter their distribution was erratic and they were not consistently detectable until Stage 5, when thecal cells first appeared. Using topical autoradiography, specific binding for FSH was evident in Stage 1-4 follicles (4 layers granulosa cells) whereas specific hCG-binding was not. After the preovulatory gonadotrophin surges, by 21:00 h on pro-oestrus, FSH receptors declined in Stages 5-10, prolactin receptors fell in Stages 8 and 10 (small and large antral follicles) and hCG receptors were reduced in Stages 7 (start of antral cavity) to 10. On the morning of oestrus, for follicles from Stage 4 onwards, receptor numbers usually returned to levels found at 09:00 h on pro-oestrus. At oestrus, the few remaining Stage 10 follicles were all atretic and contained significantly reduced FSH and prolactin receptors but numbers of hCG binding sites comparable to those at 09:00 h of pro-oestrus. These results provide evidence of gonadotrophin receptors in small primary and secondary follicles which is consistent with increased DNA synthesis in small hamster follicles on the afternoon of pro-oestrus and on the morning and afternoon of oestrus. Periovulatory changes in gonadotrophin concentrations may therefore affect early stages of folliculogenesis.

Animals↗
PubMed1987

Isolation, structural elucidation and biological properties of neoenactins B1, B2, M1 and M2, neoenactin congeners.

The structures of three neoenactin congeners, designated as neoenactins B1, B2 and M2 were elucidated by 1H and 13C NMR and mass spectroscopic studies. Another minor component, neoenactin M1, isolated from the crude mixture, was identified as lipoxamycin. All three new compounds were structurally related to neoenactin A. While B1 was proved to be a positional isomer of B2, M2 was found to be a dihydro derivative of A. All the compounds were active against yeasts and fungi and potentiated the activities of polyene antifungal antibiotics such as trichomycins A and B and amphotericin B.

Antifungal Agents↗
PubMed1986

Parkinson's disease: disability, review, and management.

Data from a descriptive study of idiopathic Parkinson's disease were analysed aimed at getting a clearer picture of the impact of the disease on the community and the help available to patients and carers. Altogether 267 patients aged 40-92 were identified, and the median duration of disease in those in whom this could be assessed was 7.2 years. Of the 267 patients, 204 (76.4%) were living in the community, 51 alone. A total of 201 patients were taking levodopa, 29 out of 102 had retired early, and 60 out of 84 (71.4%) had given up driving. Most patients had symptoms at the time of study, and signs such as bradykinesia, rigidity, impaired speech, and abnormal gait were often moderate or severe. Of 214 patients whose disease was assessed using the scoring system of Hoehn and Yahr, 78 (36.4%) had grade 4 and 23 (10.7%) grade 5 disability. Despite this, however, 105 of 265 patients (39.6%) were not subject to regular medical review and only 57 of 227 patients (25.1%) had been seen by an occupational therapist, 16 (7.0%) by a physiotherapist, and 10 (4.4%) by a speech therapist. Patients with Parkinson's disease may benefit from regular medical review and being seen by therapists.

Adult↗
PubMed1986

Parkinson's disease in a Scottish city.

In a detailed community study the total prevalence of idiopathic Parkinson's disease in Aberdeen was 164.2/10(5) of the population. The age and sex specific prevalence rose to 2657.8/10(5) (2.7%) of men and 2071.0/10(5) (2.0%) of women aged over 84. The mean age at onset, irrespective of sex, was 65.3 years (SD 12.6) and varied little compared with similar studies over the past 25 years. Half of patients were independent but 78/225 (34.7%) were considerably disabled and 23/225 (10.2%) were confined to bed or a wheelchair. Disability increased with age and also with a low minimental state questionnaire score. The score was less than or equal to 7/10 (graded 0-10) in 93/252 (37%) of patients and less than 5/10 in 28/252 (11%). Parkinson's disease remains a common and disabling condition in the community.

Adult↗
PubMed1986

Effects of altitude, ethnicity-religion, geographical distance, and occupation on adult anthropometric characters of eastern Himalayan populations.

With a view to estimating the effect of altitude on body dimensions vis-à-vis ethnicity-religion, geographical distance, and occupation, a comprehensive multivariate statistical analysis was performed on data pertaining to 16 anthropometric characters collected from 1,103 individuals (643 males and 460 females) belonging to two ethnic groups-Sherpa and Lepcha. Samples were drawn from several locations in the eastern Himalayan region-Darjeeling and Kalimpong in West Bengal (India), and Nepal, situated at low (1,000-2,000 meters) and high (above 3,500 meters) altitudes. The individuals sampled practice different occupations and follow different religions. Significant age and sex effects were observed. The data were age-adjusted, and sexes were treated separately. A test of equality of mean vectors indicated heterogeneity among population groups. Almost all characters were found to contribute significantly to the ability to discriminate between the groups. The overall probability of correctly classifying an individual based on body dimensions into the group in which she or he actually belongs was high (between 0.64 and 0.77). Shape and size factors could be identified that explained about 50% of the total variance and yielded a reasonable separation of the groups. Results of four different types of multivariate statistical analyses were in agreement, and showed that altitude is most highly associated with body dimensions.

Adult↗
PubMed1986

Fulminant amebic colitis.

Nine patients with fulminating amebic colitis who were treated surgically from 1975 to 1982 are presented. Only those who had bowel resections with exteriorization of the cut ends survived. The pertinent literature is reviewed briefly.

Adolescent↗