Synthesis of chloroplast DNA in isolated chloroplasts.

Chloroplasts isolated from Euglena gracilis incorporated both tritiated thymidine 5'-triphosphate and tritiated deoxyadenosine 5'-triphosphate into an acid-stable fraction. The incorporation was dependent on the presence of all four deoxynucleoside triphosphates and was sensitive to treatment with deoxyribonuclease and actinomycin D. It was demonstrated that bacterial contamination could not account for the incorporation of label. Extraction of DNA from the chloroplasts and subsequent density gradient centrifugation of the DNA in CsCl(2) showed that the incorporation was into chloroplast DNA (rho = 1.686) of high molecular weight.

Chonemorphine, stigmasterol, and ecdysterone: steroids isolated through bioassay-directed plant screening programs.

In a bioassay-directed screening programme of plants for the identification of active constituents the following steroids were isolated. Chonemorphine was identified as the antiamoebic and antitrichomonad principle of Chonemorpha fragrans. Stigmasterol from Coleus forskohlii and ecdysterone from Diploclisia glaucescens were inactive constituents isolated during the process of purifying the active principles of the plants. D. glaucescens roots are a high-yielding source (0.5% of the dry root weight) of ecdysterone.

Genotoxic effects of MeCCNU on human peripheral blood lymphocytes.

MeCCNU (semustine, 1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea, NSC 95441) is successfully used in the treatment of various human malignancies. The drug was tested for its in vitro genotoxic effects on human peripheral blood lymphocytes. Several drug concentrations were studied considering mean plasma level achieved in patients after the receipt of MeCCNU therapy. Induction of chromosome aberrations and sister chromatid exchange frequency had shown dose-effect relationship. Reduced mitotic activity and prolonged average generation time was observed in MeCCNU treated cultures. The results suggest that 'therapeutic' MeCCNU concentrations have genotoxic effects on human peripheral blood lymphocytes.

Serum lipoperoxide levels in pregnancy induced hypertension.

With present day awareness of role and toxicity of lipid peroxides, serum levels of lipoperoxides have been investigated in forty pregnancy induced hypertension (PIH) subjects, before and after antihypertensive drug therapy, using full term normotensive patients as control. PIH subjects demonstrated highly significant elevated serum levels of lipoperoxides (mean 3.60 nmol/ml) in comparison (mean 2.15 nmol/ml) with full term normotensive subjects. At post-partum PIH subjects following antihypertensive drug therapy and becoming normotensive showed highly significant fall in serum lipoperoxide (mean level 2.27 nmol/ml). Full term normotensive subjects at post-partum also demonstrated the same pattern. However, observed levels of serum lipoperoxide in PIH subjects at post-partum even after becoming normotensive following treatment were found to be significantly elevated when compared with those of full term normotensives at post-partum (mean level 1.94 nmol/ml). It is felt that monitoring of serum lipoperoxide level can serve as one of the useful parameters in PIH subjects.

Serum immunoglobulin status of psychiatric in-patients.

In view of the fact that substantial evidence today links psyche, brain, stress and immune system, the serum immunoglobulin (viz. IgG, IgA, IgM) levels in 40 patients with psychiatric disorders (viz. Schizophrenia, Affective disorder and generalized Anxiety disorders) have been investigated. With the exception of IgA, all psychiatric patients had significantly elevated IgG, IgM levels (p less than 0.001) when compared with healthy controls. Surprisingly these immunoglobulin levels irrespective of prevalent psychiatric disorder were almost similar to those of the hospitalized surgical patients pre-operatively (preferable controls), suggestive of no direct linear causal relationship between the psychiatric disorder and serum immunoglobulin levels. Factors affecting immunoglobulins have been discussed. Considering a probable viral association in Schizophrenia it is felt that simultaneous monitoring of viruses (affecting the nervous system) in the form of antigen/antibodies may be more informative.

Serum lipoperoxide levels in surgical stress of abdominal hysterectomy.

In continuation of our studies on stress situations in female reproductive life span, serum lipid peroxide levels in terms of malondialdehyde (nmol/ml) have been determined in females [(n = 40) (aged between 35-40 years)] to undergo total abdominal hysterectomy (due to dysfunctional uterine bleeding). There occurred a statistically significant though within physiological limits, progressive rise in serum lipid peroxide levels right from preoperative stage 3.51, per operatively 3.56 to a maximum of 4.10 postoperative stage I with a tendency of fall at postoperative stage II 3.94 in comparison with self control on admission 2.97. It is suggestive of the balancing and protective role of scavenging enzyme system like superoxide dismutase also backed by improvement in health status of abdominal hysterectomy patients in terms of ambulation, free intake of food and behavioural positive attitude within 24 hours following operation presumably due to relief from stress of DUB. It is felt from the results of the present investigation that patients undergoing abdominal hysterectomy were free from free radical toxicity.

Effects of CCNU therapy on human chromosomes.

Peripheral blood lymphocytes of 9 patients under CCNU therapy were examined for frequency of sister-chromatid exchanges (SCEs) and chromosomal aberrations (CAs). 7 out of 9 patients were treated with only CCNU, whereas the remaining 2 were treated with other chemotherapeutic agents in combination with CCNU. Compared to normal individuals, a significantly increased frequency of SCE was observed in the patients before starting anticancer therapy (P less than 0.001). Increased incidences of structural changes in chromosomes were observed in cells from all the treated patients. The most frequent aberrations were of chromatid type. After administration of a single dose of CCNU, an increase in SCE frequencies was observed which remained elevated even after 6 weeks. It was concluded that increases in SCEs and CAs in lymphocytes were caused by CCNU treatment. Further studies are needed to elucidate whether any CAs observed in the present study could participate in the induction of second neoplasm.

Three siblings with Harlequin Ichthyosis in an Indian family.

The Harlequin fetus is a distinct genetic entity with a strikingly grotesque appearance. Three siblings (two males, one female) with Harlequin Ichthyosis, a rare form of congenital disorder, born to the same parents are presented. The genetic aspects are discussed and the relevant literature is reviewed.

Cytogenetic effects of Me-CCNU on sister chromatid exchange frequency, cellular kinetics and chromosome aberrations.

1-(2-Chloroethyl)-3-(trans-4-methylcyclohexyl)-1-nitrosourea (Me-CCNU) was tested for its in vitro effects on sister chromatid exchanges (SCE), cellular kinetics and chromosome aberrations in CHO cells. There was a relationship between the inhibitory activity of the drug and the cytogenetic damage, which was dose dependent. Increase in SCE values were highly significant (p less than 0.001) for all the four concentrations used. It also delayed the cell cycle progression. Inhibition of DNA synthesis results in increased frequency of chromosomal aberrations, which was highly significant for the higher concentrations, i.e. 5 micrograms and 10 micrograms Me-CCNU/ml.

Cytogenetic studies in a population suspected to have chromosomal abnormalities.

The present study describes the cytogenetic findings in cases suspected with chromosomal abnormalities, in cases of mental retardation, multiple congenital malformations, clinical features of Down's syndrome, Klinefelter's syndrome, Turner's syndrome, ambiguous sex, sterility, amenorrhea and history of repeated spontaneous abortions in couples. Cytogenetic studies were done in 144 of the total 205 cases. In all, 57 (39.58%) were shown to have chromosomal abnormality and of these, 34 cases (25.7%) were Down's syndrome. Sex chromosome abnormality was found in 19 cases (13.2%). The results confirm the significant contribution of chromosomal abnormalities in the genesis of mental retardation, and abnormal sexual development.