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Biomedical subjects

R Shah

Publications and source records attributed to R Shah.

At least 199 records · Page 11Linked to original sources
PubMed1971

Production of anticapsin by Streptomyces griseoplanus.

Anticapsin is a new fermentation product which inhibits formation of the hyaluronic acid capsule of Streptococcus pyogenes. Production of this metabolite in a complex medium by S. griseoplanus is enhanced by high levels of carbohydrate. A number of carbon sources support biosynthesis but sucrose is most effective, the optimum level being 150 g/liter. Neither glucose nor fructose, alone or in combination, serves as an equivalent substitute for sucrose. The addition of dibasic potassium phosphate to the medium further increases anticapsin production. Dissolved oxygen levels are important for synthesis and stability of the metabolite. Anticapsular activity diminishes rapidly in previously aerated broths which are held under static conditions. This decrease does not occur in pasteurized broths or unpasteurized filtrates.

Aerobiosis↗
PubMed1970

The structure of anticapsin, a new biologically active metabolite of Streptomyces griseoplanus.

1. Physical and analytical data obtained on crystalline anticapsin indicated the empirical formula C(9)H(13)NO(4). Spectral data (u.v., i.r. and proton magnetic resonance) and formation of l-tyrosine on hydrolysis revealed the functionalities and carbon skeleton of the new epoxy keto amino acid. 2. The optical properties of anticapsin (optical rotatory dispersion and circular dichroism) permitted assignment of absolute configuration to the new metabolite. 3. Treatment of anticapsin with hot methanolic hydrochloric acid followed by acetylation gave C(18)H(19)NO(5), the alpha-alkoxycyclohexenone derivative. Analysis of the nuclear-magnetic-resonance and mass spectra of the latter allowed its structure to be determined and confirmed the assigned structure of anticapsin.

Amino Acids↗
PubMedDate not supplied

Measurement of apoptosis, proliferation and three cytokines in 46 patients with myelodysplastic syndromes.

Extensive apoptosis or programmed cell death (PCD) of both hematopoietic (erythroid, myeloid, megakaryocytic) and stromal cells in myelodysplastic syndromes (MDS) cancels the high birth-rate resulting in ineffective hematopoiesis and has been demonstrated as the probable basis for peripheral cytopenias in MDS by our group. It is proposed that factors present in the microenvironment are inducing apoptosis in all the cells whether stromal or parenchymal. To investigate this hypothesis further, bone marrow biopsies from 46 MDS patients and eight normal individuals were examined for the presence of three cytokines, tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and granulocyte macrophage-colony stimulating factor (GM-CSF) and one cellular component, macrophages, by the use of monoclonal antibodies immunohistochemically. Results showed the presence of TNF-alpha and TGF-beta in 41/46 and 40/46 cases of MDS respectively, while only 15 cases showed the presence of GM-CSF. Further a significant direct relationship was found between the degree of TNF-alpha and the incidence of PCD (p= 0.0015). Patients who showed high PCD also had an elevated TNF-alpha level. Thus, the expression of high amounts of TNF-alpha and TGF-beta and low amounts of the viability factor GM-CSF may be responsible for the high incidence of PCD leading to ineffective hematopoiesis in MDS. Future studies will be directed at attempting to reverse the lesion in MDS by using anti-TNF-alpha drugs such as pentoxifylline.

Apoptosis↗
PubMedDate not supplied

Poor quality of sperm as it affects repeated early pregnancy loss.

A study was carried out to determine whether males contribute to repeated early pregnancy loss. Semen samples were analyzed from proven-fertile men (n = 51 group I) and from men whose partners presented with early pregnancy loss (>3 first trimester abortions, n = 32 group II). Routine analysis, sperm function tests, and ultrastructural studies of sperms were carried out. Female factor could be identified in 25 (78%) couples, and in 7 (22%) no cause either male or female could be identified and the semen analysis was normal. Percent morphologically normal did not differ significantly between the groups, but increased sperm head abnormalities were seen. The functional tests were all normal except for a significant decrease in the capacity of nuclear chromatin to decondense in vitro. The ultrastructural studies showed defects of chromatin condensation and irregular nuclei with vacuoles. This study points to the loss of chromatin integrity as a possible contributing factor from males to early pregnancy loss.

Abortion, Habitual↗
PubMedDate not supplied

A study of hospital based ambulance systems in Wisconsin.

This study was undertaken to determine the advantages and disadvantages of a hospital-based emergency medical service system with hospital employees serving as emergency medical technicians. This type of service is operating in thirteen hospitals in Wisconsin. A series of interviews was conducted to obtain pertinent information regarding the hospital, emergency medical vehicles, ambulance attendants, finances, communications and personal reactions to the system. The data indicate that hospital-based services using hospital employees can operate with minimal interference to regular patient care, and with apparent advantages to the emergency patients. In the rural, sparsely populated areas which were studied, response times from the hospital-based systems were comparable to other rural systems, and the financial and administrative aspects of the system were reviewed.

Allied Health Personnel↗
PubMedDate not supplied

The investigation of major salivary gland agenesis: a case report.

Salivary gland agenesis is an extremely uncommon congenital anomaly, which may cause a profound xerostomia in children. The oral sequelae includes dental caries, candidosis, and ascending sialadenitits. The present report details a child with rampant dental caries secondary to xerostomia. Despite having oral disease for many years, the congenital absence of all the salivary glands failed to be established until early adulthood. The appropriate investigation and management of the xerostomic child allows a definitive diagnosis to be made and attention focused on the prevention and treatment of resultant oral disease.

Candidiasis, Oral↗
PubMedDate not supplied

Laparoscopic gastropexy for chronic intermittent gastric volvulus.

The traditional surgical treatment of chronic gastric volvulus involves laparotomy for derotation of the stomach and its fixation to the patients. We describe a 36-year-old man with organoaxial gastric volvulus who was treated successfully with laparoscopic gastropexy. He is asymptomatic four months later.

Adult↗
PubMedDate not supplied

Prognostic implications of white cell differential count and white cell morphology in Malaria.

BACKGROUND: Malaria is of immense importance amongst the tropical diseases in India. There is a need to develop newer diagnostic aids and research is necessary to identify new prognostic markers for prediction of the course and complications. AIMS: To evaluate the white cell differential count and morphology in Plasmodium vivax and Plasmodium falciparum malaria and study their prognostic utility. SUBJECTS AND METHODS: Two hundred and sixty-four adult patients in the age range of 20 to 65 years presenting to the hospital over a period of 4 months with clinical features of malaria and a positive peripheral smear examination were studied. RESULTS: No statistically significant difference was noted in the white blood cell (WBC) count and neutrophil count in P.vivax versus P. falciparum malaria. Band cells were more frequently noted in P. falciparum malaria than in P.vivax malaria (p < 0.0001). Toxic granulation of the neutrophils was noted in 9.5% of the patients and exclusively in P. falciparum malaria. Presence of toxic granulation of the polymorphs in subjects with P. falciparum malaria was significantly associated with anaemia (p=0.019), jaundice, cerebral involvement, adult respiratory distress syndromes, renal dysfunction and death (p < 0.0001 for all these parameters). CONCLUSION: Band cells were seen in P. vivax and P. falciparum malaria, although in higher numbers in P. falciparum malaria. Toxic granulation of the neutrophils was noted only in the presence of P. falciparum malaria in this study and correlated with severity.

Adult↗