Biomedical subjects

M Sujatha

Publications and source records attributed to M Sujatha.

8 recordsLinked to original sources

PubMed2004

Stable genetic transformation of castor (Ricinus communis L.) via Agrobacterium tumefaciens-mediated gene transfer using embryo axes from mature seeds.

A protocol for the transformation of castor embryo axes using the pCAMBIA vector 1304 in disarmed Agrobacterium tumefaciens strain EHA105 is presented. Co-cultivated explants were initially subjected to expansion and proliferation on MS medium with 0.5 mg l(-1) TDZ followed by three cycles of selection on medium with 0.5 mg l(-1) BA and increasing concentrations of hygromycin (20-40-60 mg l(-1)). Selected shoot clusters were transferred to medium with 0.5 mg l(-1) BA for proliferation and 0.2 mg l(-1) BA for shoot elongation. Elongated shoots were rooted on half-strength MS medium with 2.0 mg l(-1) NAA. The presence and stable integration of the hpt gene was confirmed through PCR, RT-PCR, PCR-Southern blot, sequence analysis, Southern blot analysis and PCR analysis of progeny. Southern blot analysis of the primary transformants showed single copy integration and progeny analysis revealed monogenic inheritance of the introduced gene. This paper reports the first successful attempt at producing transgenic castor.

Agrobacterium tumefaciens↗

PubMed2001

Parental age and the origin of extra chromosome 21 in Down syndrome.

We present a report of the parental ages (n = 865) and parental origin of meiotic nondisjunction (n = 236) that are likely to show a predisposition in the etiology of Down syndrome (DS). Chromosomal analysis, performed over a 20-year period, on 1,001 Down syndrome subjects, revealed pure trisomy 21 karyotype in 880 subjects (87.92%), mosaic trisomy karyotype in 77 (7.69%), and translocation karyotype in 44 (4.39%). The mean maternal age was found to be 30.34 years, and mean paternal age was 31.04 years. Nondisjunctional error was 79.24% maternal and 20.76% paternal. The findings of the study revealed the significant contribution of advanced parental age and increased maternal meiotic nondisjunctional error to the origin of trisomy 21 Down syndrome.

Adult↗

PubMed2000

Cytogenetic studies of 1001 Down syndrome cases from Andhra Pradesh, India.

Cytogenetic data obtained from investigating 1001 patients of Down syndrome (DS) and their parents over a period of 20 years (January 1979-January 1999) are presented. The frequency of pure trisomy, mosaicism and translocation was 87.92, 7.69 and 4.39 per cent respectively. The origin of the extra chromosome 21 due to meiotic non-disjunction was 79.24 per cent maternal and 20.76 per cent paternal. A high frequency of acrocentric chromosome associations was also observed in mothers of children of Down syndrome, this might have predisposed to an enhanced risk for non-disjunction. Birth order of DS showed a higher number of first and second borns. Reproductive performances of the parents indicated a high rate of abortions, compared to controls. Cytogenetic investigations carried out over these years greatly helped in the management of these children and for counseling the affected families.

Adolescent↗

PubMed1999

Serum and erythrocyte magnesium levels in hypertensives and their first degree relatives.

Essential hypertension is an arbitrarily defined disorder to which both genetic and environmental factors contribute. Magnesium and its interactions with other cations may play an important role in the pathogenesis of essential hypertension. Various studies have been carried out on the levels of serum and erythrocyte magnesium in hypertensives and the results are controversial and there is no systematic study in Indian population. In the present study serum and erythrocyte magnesium levels in 86 hypertensives and their 77 first degree relatives as well as in sex and age matched controls were studied. Serum and erythrocyte magnesium levels showed a significant decrease both in the hypertensives and their first degree relatives (p < 0.01). The significantly decreased levels of magnesium in the first degree relatives suggest genetic basis of essential hypertension and may be used as marker to identify those at risk.

Biomarkers↗

PubMed1998

Erythrocyte sodium and Na+, K(+)-ATPase activity in untreated hypertensives and their first degree relatives.

In this paper we report the erythrocyte sodium concentration and Na+, K(+)-ATPase activity in 86 untreated hypertensives and their 77 first degree relatives and also in sex and age matched controls. There was significant increase in erythrocyte sodium both in the hypertensives and their first degree relatives (p < 0.01), whereas Na+, K(+)-ATPase activity was significantly reduced in the study group when compared with controls. The possibility of using these parameters as genetic markers is suggested.

Blood Pressure↗

PubMed1997

Maternal reproductive history and the occurrence of Down's syndrome.

Reproductive history of mothers of 115 Down's syndrome children was studied and compared with 200 control mothers who gave birth to normal children. The frequency of spontaneous abortions in mothers of Down's syndrome babies was found to be elevated significantly (p < 0.05). The data suggest that the maternal health and reproductive potential have a prominent aetiological significance in the occurrence of Down's syndrome.

Abortion, Spontaneous↗

PubMed1991

Identification of two novel cerebrospinal fluid proteins in non specific mental retardation.

Cerebrospinal fluid (CSF) from twenty three patients with non specific mental retardation and fourteen age matched normal samples was subjected for qualitative analysis of protein profiles by two-dimensional gel electrophoresis (2-DE) and the proteins were visualised by ultra sensitive silver staining. Two proteins designated as mental retardation associated proteins (MRAP-I and MRAP-II) were identified in six male patients out of twenty three patients CSF samples. MRAP-I had an isoelectric point of 7.4 with a relative molecular weight 16.5 kDa, while MRAP-II had an iso-electric point of 7.2 with a relative molecular weight 16.8 kDa. The two proteins are presumed to be originated from brain, as they could not be traced in the serum of patients, nor due to proteolytic degradation. Despite unknown origin and identity, their presence in the CSF of a specific group of mentally retarded male patients suggest their possible clinical utility and to define protein alterations in mental retardation.

Adolescent↗

PubMed1989

Segregation frequency in microcephaly.

A total of 118 cases of microcephaly were clinically evaluated under two main groups: primary microcephaly (61 cases) and secondary microcephaly (57 cases). Secondary cases were generally characterized by convulsions, spasticity, and other congenital anomalies. Estimates of segregation frequency obtained separately in primary and secondary cases indicated that the primary consanguineous cases were most probably due to a single recessive gene. The segregation frequency was substantially less in other types, indicating much lower genetic risks in these cases.

Consanguinity↗