Search PubMed⌕ Search

Biomedical subjects

S Sanyal

Publications and source records attributed to S Sanyal.

At least 37 records · Page 2Linked to original sources
PubMed1997

Cell mediated immune status in malignancy--pretherapy and post-therapy assessment.

Twenty-eight cases of malignancies of different kinds were studied to assess T-cell activity and population before and after institution of therapy. Fifteen cases were diagnosed as non-metastasising squamous cell carcinoma of larynx, pharynx, laryngopharynx, hypopharynx and tonsils. Seven cases were non-metastasising infiltrating duct carcinoma of breast and 6 cases were non-Hodgkin's lymphoma (NHL). It was observed that 3 out of 15 cases (20%) of squamous cell carcinoma cases were Mantoux test (MT) negative with a T-cell population of less than 40%, 2 out of 7 cases (28.6%) of infiltrating duct carcinoma of breast were MT negative with a T-cell population of less than 40% and 3 out of 6 cases (50%) of NHL were MT negative with a T-cell population of less than 40%. The normal controls, consisting of apparently normal healthy adults, had a T-cell population of more than 40% and were all MT positive. The patients who showed a negative skin test and a T-cell population less than 40% were further subjected to assessment of T-cell population and activity after appropriate therapy, and clinical cure of the disease. It was observed that 2 out of 3 cases (66.66%) of squamous cell carcinomas, 2 out of 2 cases (100%) of adenocarcinomas and one out of 3 cases (33.33%) of NHL showed positive conversion with a T-cell population of more than 40%.

Adult↗
PubMed1997

A comparative study of silver binding nucleolar organiser regions (AgNORs) of breast lesions in histological sections and fine needle aspiration smears.

The study presents a comparative profile of AgNOR dot counting in different types of breast lesions in histopathological (HP) sections and fine needle aspiration cytology (FNAC) smears. The breast lesions chosen were non-neoplastic lesion like fibroadenosis, benign neoplastic lesion like fibroadenoma and malignant neoplastic lesion like infiltrating duct carcinoma-grade 2. The AgNOR counts of non-neoplastic lesion were significantly less in number than the neoplastic lesions--both benign and malignant, in both the HP section and FNAC smear. But the counts did not show significant difference in the two neoplastic lesions eg, fibroadenoma and infiltrating duct carcinoma-grade 2, in both the HP section and FNAC smear. The appearance of the dots, as felt by the observers, were more discriminating between the three lesions, eg, uniform small compact centrally placed in fibroadenosis; mostly uniform small compact but occasional large irregular in fibroadenoma and large irregular marginally located in infiltrating duct carcinoma. Counting was easier and the appearance of the dots more easily discernible in FNAC smear than the HP section as the smear was monolayer and the malignant cells were easily detected from macrophages and stromal cells. But the tissue fluid or secretions or blood when present in the smear gave the smear a dirty background which was disturbing to the observers. Thus this AgNOR technique, when applied in HP section or FNAC smear, appears cost ineffective, lengthy and tedious procedure; did not offer absolute histochemical discriminant for malignancy from benignancy. But the shape and size distribution and appearance of the dots showing much variability in FNAC smear than the HP section, might be of some help in the diagnosis of malignancy and discriminating from benignancy.

Biopsy, Needle↗
PubMed1997

Pre-labour rupture of membrane: the histological study of membrane and bacteriological profile.

One hundred two (102) cases of pre-labour rupture of membrane (PROM) were studied and special attention was given to the histological study of the amniotic membrane as well as to the bacteriological study of high vaginal flora, cervical flora and flora of amniotic fluid, in search of probable causes or factors leading to PROM. The incidence was found to be 3.16% in the age group of 20-25 years without any relation to parity; and the duration of gestation was 38 to 40 weeks in most of the cases. The histological study revealed: (a) Focally denuded amniotic epithelium, focally separated amniotic epithelium from chorion layer, lesser density of focal squamoid change of the epithelium and thicker chorion layer probably indicating focal immaturity of the chorio-amnion, (b) lesser thickness of collagen layer, focal hydropic degeneration and mild cellular infiltrate, (c) presence of focal hyaline degeneration and focal calcification of chorio-amnion. Microbial culture revealed: (a) Higher rate of positive culture in high vaginal swab, cervical swab and amniotic fluid showing presence predominantly of Esch coli, Strept haemolyticus, klebseilla species, Staph aureus, Strept non-haemolyticus, proteus species and pseudomonas species against that of positive cultures in the control cases, (b) no anaerobic bacteria from high vaginal swab, cervical swab or from amniotic fluid. It was presumed that focal immaturity of chorio-amnion or focal irregularity in the chorio-amnion at the microscopical level, focal degeneration of collagen superadded with bacterial infection, however mild, could be the factors leading to weakness in the tensile strength of chorio-amnion, again leading to PROM, in the face of stress factors of foetal origin.

Adult↗
PubMed1996

Cryptic initiation at the human D4 receptor reveals a functional role for the amino terminus.

It was found that deletion of the initiator methionine of the D4 receptor results in the use of a cryptic initiation site in the putative first transmembrane region. We made use of this observation to investigate the role of the amino terminus of the D4 receptor. In vitro transcription and translation of D4.4 and a D4.4 deleted for the initiation codon (D4.4 delta NH2) resulted in the formation of protein products with a molecular mass of about 44 and 40.5 kDa, respectively. The molecular mass of 40.5 kDa suggests initiation in the putative first transmembrane region. Transient expression of various deletion mutants indicated that this receptor form can be expressed at up to 70% of the D4.4 control levels and provided support for the existence for an alternative translation initiation site in the first transmembrane domain, most likely at nucleotide +112 (the initiator methionine codon is designated as +1). The D4.4 delta NH2 mutant was stably expressed in CHO cells. Pharmacological analysis demonstrated no major differences in antagonist binding with the regular D4.4 receptor, while dopamine and quinpirole binding affinities were about 5-fold decreased. The half-maximal level (EC50) for blocking forskolin-stimulated cAMP levels by dopamine was about 10-fold lower as compared to D4.4. Furthermore, the functional efficacy is decreased by about 40%. These data suggest that the amino-terminal domain is not essential for proper expression, but does interfere with the functional activity of the receptor, possibly through stabilization of the active state. To our knowledge this is the first demonstration that the amino terminus of a dopamine receptor is involved in signal transduction.

Animals↗
PubMed1996

Dopamine D4 receptor variant in Africans, D4valine194glycine, is insensitive to dopamine and clozapine: report of a homozygous individual.

The D4Valine194Glycine receptor is a variant of the dopamine D4 receptor and is found in 12.5% of the Afro-Caribbean population. Glycine replaces valine at a position one amino acid away from a serine which is critical for the attachment of dopamine. To determine whether this mutation had an effect on the properties of the dopamine D4 receptor, we constructed this variant and tested the sensitivity of the expressed protein with various drugs. We found that the variant receptor was two orders of magnitude less sensitive to dopamine, clozapine and olanzapine. The variant receptor was insensitive to guanine nucleotide, indicating the absence of a high-affinity state or functional state. The one 15-year-old individual found homozygous for this variant also had sickle cell disease. The patient revealed an overall pattern of low weight and no axillary or pubic hair.

Adolescent↗
PubMed1996

Fine needle aspiration cytology of ophthalmic lesions.

Forty cases of ophthalmic lesions were subjected to fine needle aspiration cytology for pre-operative diagnosis which included retinoblastomas (5 cases), inflammatory and neoplastic lesions of the eyelid and lacrimal glands (29 cases) and extra-ocular orbital lesions (6 cases) inclusive of 3 cases of rhabdomyosarcomas. The lesions were distributed in both the eyes almost in equal proportions. Histological confirmation was obtained in 85% of cases; false positive in only one case with malignant neoplasm of the eyelid and false negative also in only one case with inflammatory pseudotumour which were, histologically, proved to be adenoma of tarsal gland and lymphocytic lymphoma respectively.

Biopsy, Needle↗
PubMed1995

Modulation of intracellular cyclic AMP levels by different human dopamine D4 receptor variants.

To investigate whether polymorphic forms of the human dopamine D4 receptor have different functional characteristics, we have stably expressed cDNAs of the D4.2, D4.4, and D4.7 isoforms in several cell lines. Chinese hamster ovary CHO-K1 cell lines expressing D4 receptor variants displayed pharmacological profiles that were in close agreement with previous data from transiently expressed D4 receptors in COS-7 cells. Dopamine stimulation of the D4 receptors resulted in a concentration-dependent inhibition of the forskolin-stimulated cyclic AMP (cAMP) levels. The potency of dopamine to inhibit cAMP formation was about twofold reduced for D4.7 (EC50 of approximately 37 nM) compared with the D4.2 and D4.4 variants (EC50 of approximately 16 nM). Antagonists block the dopamine-mediated inhibition of cAMP formation with a rank order of potency of emonapride > haloperidol = clozapine >> raclopride. There was no obvious correlation between the efficacy of inhibition of forskolin-stimulated cAMP levels and the D4 subtypes. Dopamine could completely reverse prostaglandin E2-stimulated cAMP levels for all three D4 receptor variants. Deletion of the repeat sequence does not affect functional activity of the receptor. The data presented indicate that the polymorphic repeat sequence causes only small changes in the ability of the D4 receptor to block cAMP production in CHO cells.

Animals↗
PubMed1995

Study of benign superficial cysts by fine needle aspiration cytology.

Fine needle aspiration cytology of 213 cases of different cystic lesions from various regions of body and different superficial organs was analysed in an attempt to present the experience of the authors in the diagnosis of such lesions. The predominant lesion diagnosed by fine needle aspiration cytology was adnexal cyst/sebaceous cyst (41 cases) followed by vascular hamartoma (40 cases) and thyroglossal cyst (9 cases). One hundred fifty-eight (74.2%) out 213 cases were confirmed histopathologically. There was false negative diagnosis in 14 cases (6.6%). The remaining 41 (19.2%) cases did not turn up for further treatment. The fallacies that have been recorded in the diagnosis of thyroid cysts, salivary gland cysts and breast cysts in respect of papillary cystic thyroid carcinoma, muco-epidermoid carcinoma of salivary gland and intraductal carcinoma with fibrocystic disease of breast respectively have been highlighted in the present study.

Biopsy, Needle↗
PubMed1995

Fine needle aspiration cytology of bone and joint lesions: an assessment.

Fine needle aspiration cytology and subsequent correlation with histology and therapeutic follow-up was done in 198 cases of bone and joint lesions. Overall accuracy was found to be 87.34%; false diagnosis was recorded in 4.5% of cases; 8.08% cases were excluded from correlation as they did not turn up for further treatment or follow-up after the diagnosis. False diagnosis was encountered mostly with inflammatory lesions and primary neoplasms, diagnosing osteosarcoma and Ewing's sarcoma as chronic inflammatory lesion, chondroma as chondrosarcoma and vice versa. The possible cause of default has been discussed. The benign cystic lesions could be diagnosed with almost 100% accuracy by fine needle aspiration cytology where 10% cases were excluded as they could not be followed up.

Biopsy, Needle↗