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Biomedical subjects

R Sarkar

Publications and source records attributed to R Sarkar.

At least 91 records · Page 5Linked to original sources
PubMed1991

Hypertensive primary intraventricular haemorrhage.

A case of hypertensive primary intraventricular haemorrhage is reported. The patient recovered with conservative management. To the best of our knowledge, there has been no previous report of this rare entity in Indian literature.

Adult↗
PubMed1991

Mortality in neonatal septicemia with involvement of mother in management.

In most Special Care Neonatal Units (SCNUs) in India, mothers are excluded from the care of their sick babies for fear of over-crowding and dislocation. We have attempted to study the feasibility of involving mothers in the care of their babies admitted for neonatal septicemia and to analyse whether this changed the sepsis related case fatality rate. The study material consisted of 158 neonates with blood culture positive neonatal septicemia whose mothers were actively involved in their care during their stay in the SCNU of LNJPN Hospital throughout 1987-88. The mothers lived in with their sick neonates and were extremely useful in feeding, cleaning, and monitoring for some important signs and symptoms. There were no epidemics of infection in the nursery during this period. All the babies discharged were receiving breast feeds, and the mothers were confident in taking care of them before discharge. The mortality in this group was 43%. The onset of septicemia was most often in the first week (36%) being 25.9% in second week, 26.6% in the third, and 11.4% in the fourth. Mortality was maximum (64.5%) when the onset of illness was in the first 3 days. Klebsiella and S. aureus were commonly isolated organisms (38.6 and 21.5%, respectively). Gram negative organisms were isolated in 66.5% cases with higher mortality in this group. Nearly 46% of the babies weighed 2 kg or less, with a mortality of 60.2% compared to 28.2% in those more than 2 kg. Only 3 to 5% and 40 to 66.7% of Gram negative and 23 and 70% of Gram positive organisms were sensitive to ampicillin and gentamicin, respectively.

Bacteremia↗
PubMed1991

Antimicrobial resistance among gram-negative bacilli to newer aminoglycosides and beta-lactams.

Two hundred and fifty nine i.e. 30.72% of 843 strains of gram negative bacilli were resistant to gentamicin. When tested against newer aminoglycosides, 48.9% were resistant to tobramycin, 4.1% to amikacin and 20.5% to netilmicin. Marked cross-resistance between gentamicin and tobramycin was seen. All these strains were resistant to ampicillin, amoxycillin and co- trimoxazole. However, a high level of antimicrobial activity was seen with third generation cephalosporins, cefotaxime and ceftriaxone. Minimum inhibitory concentrations of gentamicin and tobramycin were of significant level. Gentamicin resistance could be transferred directly in 20 of 45 strains of S. typhimurium where conjugation experiments were done.

Aminoglycosides↗
PubMed1991

Arterial aneurysms in children: clinicopathologic classification.

Thirty-one arterial macroaneurysms in 23 pediatric-aged patients (16 boys and 7 girls) were treated at the University of Michigan. The average age at time of diagnosis was 10.2 years (range 6 months to 18 years). Vessels involved the aorta (4), as well as hepatic (1), splenic (2), gastroepiploic (1), renal (12), iliac (1), superficial femoral (4), popliteal (1), brachial (1), radial (2), and ulnar (2) arteries. Twelve children exhibited overt clinical manifestations including presence of a mass (7), local pain (3), hematemesis (1), and painless obstructive jaundice (1). Eleven children had asymptomatic lesions. Aneurysm existence was confirmed by arteriography or operation. All but one child underwent surgical therapy, with 20 long-term survivors (mean follow-up 3.5 years). One operative death occurred and one death occurred 6 years after surgery. This experience and a review of previously reported cases served as a basis for categorization of childhood aneurysmal disease as true aneurysms associated with (I) arterial infection, (II) giant-cell aortoarteritis, (III) autoimmune connective tissue disease, (IV) Kawasaki's disease, (V) Ehlers-Danlos syndrome or Marfan's syndrome, (VI) other forms of noninflammatory medial degeneration, (VII) arterial dysplasias, (VIII) congenital-idiopathic factors, as well as (IX) false aneurysms associated with extravascular events causing vessel wall injury or disruption. Knowledge of the varied clinicopathologic characteristics of arterial aneurysms in children is important in treating these patients.

Adolescent↗
PubMed1991

Abdominal aneurysms in childhood: report of a case and review of the literature.

Abdominal aneurysms are rare in children and are usually found in association with congenital cardiac or aortic malformations, connective tissue disorders, trauma, or previous arterial catheter placement. A 4-year-old girl who had a common iliac artery aneurysm, who had no history of arterial catheter placement or trauma, and who had no evidence of Marfan's or Ehlers-Danlos syndrome, arteritis, coarctation of the aorta, or other diseases associated with childhood aneurysms is presented. Resection of the aneurysm and arterial reconstruction were performed without the use of prosthetic material or vein graft. Pathologic examination showed no evidence of inflammation or medial degeneration in any of the layers of the arterial wall. This is the fourth report found in the literature of documented idiopathic abdominal aneurysm in a child. The conditions associated with abdominal aneurysms in childhood are discussed, and the literature is reviewed.

Abdomen↗
PubMed1990

Elevated G gamma:A gamma globin chain ratio in homozygous beta thalassemia.

G gamma:A gamma chain ratios were determined in homozygous beta thalassemia and cord blood samples using triton-urea polyacrylamide gel electrophoresis. The mean G gamma/G gamma + A gamma proportion in the two groups were 0.62 +/- 0.10 and 0.72 +/- 0.03, respectively. There was no significant correlation of the gamma chain composition in either fetal hemoglobin or total hemoglobin levels; this suggests that these two factors do not influence gamma chain ratios. There was also no marked variation in the G gamma:A gamma ratios in beta thalassemia patients when they were divided into higher fetal hemoglobin (greater than 50%) and lower fetal hemoglobin (less than 50%) groups. These observations are consistent with the finding of a selective advantage of G gamma chains over A gamma chains in disorders where the erythropoietic stress is higher than normal, and may be inherited as a specific genetic entity in haplotypic polymorphism.

Fetal Blood↗
PubMed1990

The polymorphic human DNA sequence D8S8 assigned to 8q13-21.1, close to the carbonic anhydrase gene cluster, by isotopic and nonisotopic in situ hybridization and by linkage analysis.

Restriction fragment length polymorphism at the D8S8 locus is explained by the occurrence of at least two alternative alleles at two separate TaqI sites; TaqI-A allele frequencies 0.73 and 0.27 and TaqI-B allele frequencies 0.94 and 0.06. The D8S8 locus has been assigned to 8q13-21.1, near to the carbonic anhydrase (CA) gene cluster, by in situ hybridization to metaphase chromosomes using both tritium and immunofluorescently labelled probes. Linkage analysis using the CEPH family DNA panel indicates a close genetic linkage between D8S8 and CA3, with a lod score of +7.80 at theta = 0.05 in males.

Alleles↗
PubMed1990

The role of adrenalectomy in Cushing's syndrome.

Forty-four patients with Cushing's syndrome were treated by adrenalectomy between 1975 and 1989. Twenty patients had adrenal adenomas: 13 with obvious Cushing's syndrome and 7 whose disease was subclinical, detected after evaluation of an incidentally discovered adrenal mass (es). Twelve patients underwent bilateral adrenalectomies for Cushing's disease after failed transsphenoidal explorations and pituitary irradiation. Six patients had primary adrenal hyperplasia, five as manifestations of Carney's complex. Two others underwent bilateral adrenalectomies for ectopic adrenocorticotropic hormone from carcinoid tumors. Four patients had adrenocortical carcinoma treated with transabdominal adrenalectomy. Three are alive from 8 years to 5 months. There was one postoperative death (2.3%) caused by coagulopathy and multiple organ failure and three (7%) minor postoperative complications. Follow-up showed good to excellent results in 95% of patients. It is concluded that adrenalectomy provides prompt relief from the severe morbidity of Cushing's syndrome regardless of the cause. It is the treatment of choice for adrenal adenomas, carcinomas, primary hyperplasia, and selected patients with Cushing's disease.

Adenoma↗
PubMed1990

Cronkhite-Canada syndrome with hypothyroidism.

An elderly man with non-familial gastrointestinal polyposis, malabsorption and progressive hypoproteinemia is reported. Associated alopecia, cutaneous hyperpigmentation and nail dystrophy with loss of nails were consistent with the diagnosis of Cronkhite-Canada syndrome. Hypothyroidism was present in this patient and the rare association of these two conditions is discussed.

Aged↗
PubMed1989

Serum calcium level in patients with carcinoma of the cervix in relation to menstrual status.

Serum levels of calcium and phosphorous were evaluated in patients with carcinoma of the cervix between pre- and post-menopausal women and compared the same with various normal female populations of different physiological status, involving premenopause, postmenopause and third trimester of pregnancy. Hypercalcemia was noted both in premenopausal and postmenopausal cervix cancer patients although this is more marked in the latter. No definite relationship was observed between serum calcium and phosphorous (inorganic) level. The discordance in serum calcium level assumes significance in the light of hormonal status between the pre- and postmenopausal state of cancer patients.

Adult↗
PubMed1988

Sensitivity of a human oral carcinoma cell line to retinoic acid.

We have examined the effect of retinoic acid (RA) on proliferation of KB cells in both anchorage dependent and independent growth conditions. Our study shows that RA can cause a reduction in cell proliferation rate both in monolayer and in agar cultures. After 48 h of exposure to RA, the cells started to assume a flattened appearance and no longer formed multilayers. RA treatment also caused increase in generation time, reduction in saturation density and induced cell-to-substratum adhesiveness. These changes were reversed within 48 h after removal of RA from growth medium. The results show that this cell line is sensitive to RA-induced growth inhibition and morphologic alterations which are generally associated with reduced expression of the malignant phenotype.

Cell Adhesion↗
PubMed1988

Infrared laser bone ablation.

The bone ablation characteristics of five infrared lasers, including three pulsed lasers (Nd:YAG, lambda = 1,064 micron; Hol:YSGG, lambda = 2.10 micron; and Erb:YAG, lambda = 2.94 micron) and two continuous-wave lasers (Nd:YAG, lambda = 1.064 micron; and CO2, lambda = 10.6 micron), were studied. All laser ablations were performed in vitro, using moist, freshly dissected calvarium of guinea pig skulls. Quantitative etch rates of the three pulsed lasers were calculated. Light microscopy of histologic sections of ablated bone revealed a zone of tissue damage of 10 to 15 micron adjacent to the lesion edge in the case of the pulsed Nd:YAG and the Erb:YAG lasers, from 20 to 90 micron zone of tissue damage for bone ablated by the Hol:YSGG laser, and 60 to 135 micron zone of tissue damage in the case of the two continuous-wave lasers. Possible mechanisms of bone ablation and tissue damage are discussed.

Animals↗
PubMed1986

Electrostatic attraction governs the dimer assembly of human hemoglobin.

We have investigated the effect of surface charge on the rate of assembly of alpha beta dimers of human hemoglobin A: alpha + beta k a----alpha beta. Heme intact beta A subunits were compared with four mutant subunits which differ by integral units of charge: beta N(Lys-95----Glu) (2-); beta J(Gly-16----Asp) (1-); beta S(Glu-6----Val) (1+); beta C(Glu-6----Lys) (2+). Subunit competition experiments were performed as follows. Varying amounts of 3H-labeled alpha A subunits were added to a mixture containing equal amounts of beta A and beta X subunits so that alpha/(beta A + beta X) ranged from 0.05-1.0. The reconstituted 3H-labeled Hbs A and X were analyzed by ion-exchange high pressure liquid chromatography as well as by gel electrofocusing and fluorography. Under the solvent conditions employed (10 mM PO4(Na), pH 7.0, 0 degrees C) a predominant proportion of the beta subunits was monomeric. Therefore, the ratio of Hb X to Hb A formed from subunit reconstitution when alpha/(beta X + beta A) approached zero provides a direct measure of the relative rates of monomer combination: kXa/kAa. The experimental values of this ratio decreased monotonically with the overall charge of the variant beta subunit: beta N = 2.6; beta J = 1.5; beta S = 0.41; beta C = 0.13. In contrast surface charge had no significant effect on the rate of dissociation of the alpha beta dimer: alpha beta kd----alpha + beta. At pH 8.0, where the alpha chains lack a net surface charge, they combined equally well to beta A and beta C chains. These experiments are consistent with a two-step mechanism, alpha + beta in equilibrium (alpha...beta) in equilibrium alpha beta, where the oppositely charged monomers diffuse together under the influence of their mutual electrostatic interaction to form a nonspecifically bound encounter complex [alpha...beta] that undergoes a surface charge-independent rearrangement to form the stable dimer.

Chromatography, High Pressure Liquid↗