PubMed Health⌕ Search

Biomedical subjects

I Sharma

Publications and source records attributed to I Sharma.

16 recordsLinked to original sources
PubMed2001

Complete nucleotide sequence of the 6 kb element and conserved cytochrome b gene sequences among Indian isolates of Plasmodium falciparum.

The malaria parasite contains a nuclear genome with 14 chromosomes and two extrachromosomal DNA molecules of 6 kb and 35 kb in size. The smallest genome, known as the 6 kb element or mitochondrial DNA, has been sequenced from several Plasmodium falciparum isolates because this is a potential drug target. Here we describe the complete nucleotide sequence of this element from an Indian isolate of P. falciparum. It is 5967 bp in size and shows 99.6% homology with the 6 kb element of other isolates. The element contains three open reading frames for mitochondrial proteins-cytochrome oxidase subunit I (CoI), subunit III (CoIII) and cytochrome b (Cyb) which were found to be expressed during blood stages of the parasite. We have also sequenced the entire cyb gene from several Indian isolates of P. falciparum. The rate of mutation in this gene was very low since 12 of 14 isolates showed the identical sequence. Only one isolate showed a maximum change in five amino acids whereas the other isolate showed only one amino acid change. However, none of the Indian isolates showed any change in those amino acids of cyb which are associated with resistance to various drugs as these drugs are not yet commonly used in India.

Amino Acid Sequence↗
PubMed2001

Allelic variation in the cg2 gene does not correlate with chloroquine resistance among Indian Plasmodium falciparum isolates.

The cg2 gene of Plasmodium falciparum has been proposed to be associated with chloroquine resistance. Here we describe PCR amplification and sequencing of all the four repeat regions (kappa (kappa), gamma (gamma), psi (psi) and omega (omega)) of this gene, from Indian isolates. There were variant forms for each of these repeat regions (two for kappa and gamma, and three for psi and omega) among the 123 Indian isolates of P. falciparum. Among these isolates certain forms of psi and omega repeats were uniquely present while some of the reported forms of the kappa and omega repeats were absent. The pattern of combination of all four repeat regions of cg2 gene (genotype) was analysed from 52 isolates. A total of 11 different genotypes were observed among these cases, of which 10 were unique to Indian isolates. Certain genotypes were more common than others. The nucleotide sequencing of all the four repeat regions revealed that Indian isolates have some unique repeating units within the gamma and omega domains. Altogether, the PCR and sequencing results showed that there was an unrelatedness between cg2 repeats and chloroquine resistance.

Alleles↗
PubMed1994

Antiatherosclerotic effects of fish extract feeding in rabbits.

The feeding of a fish extract, prepared by extracting whole fish with 80% ethanol, prevented abdominal, thoracic aorta and coronary atheroma in cholesterol-fed rabbits. Daily fish extract feeding reduced serum cholesterol and LDL-cholesterol levels by 41.8 and 38.0%, respectively. In addition, triglyceride levels were reduced by 52.8%. Hepatic and aortic contents of cholesterol and phospholipids approached normal levels in cholesterol-fed rabbits on the fish extract diet. Fish extract feeding induced a greater fecal excretion of cholesterol. Plaque formation was very little or absent in the aorta of fish-fed rabbits.

Animals↗
PubMed1993

Psychiatric morbidity in the first-degree relatives of schizophrenic patients.

First-degree relatives (FDRs) of 162 schizophrenic and 106 control probands were investigated [corrected]. Psychiatric morbidity was present in 34.8% of FDRs of schizophrenic probands and in 9.2% of FDRs of controls. There was significantly more psychiatric illness in the siblings and parents than in the offspring of both schizophrenic and control subjects. The morbidity risks for schizoid-schizotypal personality disorders, cannabis-use disorder and paranoid personality disorder were significantly higher in the FDRs of schizophrenic patients than in those of controls, suggesting a biological relationship.

Adolescent↗
PubMed1992

Psychiatric morbidity in the families of paranoid and non-paranoid schizophrenia patients.

A total of 1018 and 812 first degree relatives (FDR) of schizoprencies and controls respectively, were studied to find out the psychiatric morbidity in the families of paranoid and non-paranoid schizophrenia patients. The risk of schizophrenia and affective disorders was found to be independent of the probands subtype diagnosis. The risk for schizoid-schizotypal and paranoid personality disorders was found to be increased in the first degree relatives of paranoid schizophrenic, as compared to non-paranoid schizophrenic, thus suggesting that the psychopathology in the FDR may differ with the subtype diagnosis of the proband.

Adolescent↗
PubMed1991

Hypolipidaemic and antiatherosclerotic effects of plumbagin in rabbits.

Plumbagin (2-methyl-5-hydroxy, 1:4 naphthoquinone) isolated from the roots of Plumbago zeylanica when administered to hyperlipidaemic rabbits, reduced serum cholesterol and LDL-Chol. by 53 to 86 percent and 61 to 91 percent respectively. It lowered cholesterol/phospholipid ratio by 45.8 percent and elevates the decreased HDL-Chol significantly. Further, Plumbagin treatment prevented the accumulation of cholesterol and triglycerides in liver and aorta and regressed atheromatous plaques of thoracic and abdominal aorta. Plumbagin treated hyperlipidaemic subjects excreted more fecal cholesterol and phospholipids. In conclusion-Plumbagin feeding brings about a definite regression of atheroma and prevents the accumulation of cholesterol and triglycerides in liver and aorta.

Animals↗
PubMed1988

C-nor-9,11-secoestranes as modified estrogens and fertility regulation.

The synthesis of C-nor-9,11-secoestradiol (4) has been achieved from 17 beta-acetoxy-11-chloro-3-methoxy-C-nor-9,11-secoestra-1,3,5(10)-tr ien-9-one (1) through a sequence of reactions without affecting the stereochemistry of estradiol-17 beta. Removal of the 9-keto function of 1 by hydrogenolysis and its subsequent treatment with Na/NH3 gives C-nor-9,11-secoestradiol 3-(methyl ether) (3), which has been demethylated under alkaline conditions to furnish C-nor-9,11-secoestradiol (4). Pyridinium chlorochromate oxidation of 3 gives the corresponding 17-ketone 6. Jones' oxidation of 4 to the ketone 5 and reaction of 5 and 6 with lithium acetylide gives corresponding 17 alpha-ethynyl derivatives 7 and 8. Relative binding affinity to estradiol-17 beta receptors and uterotropic, antiuterotrophic, and antiimplantation activities of compounds 3-8 have been studied. The effect of conformational flexibility on ligand-receptor interaction of these compounds is discussed.

Animals↗