Long-term conservation through cryopreservation of immature seed of Mantisia spathulata and Mantisia wengeri; two endangered plants of north-east India.

A successful protocol for long-term conservation of two endangered plants viz. Mantisia spathulata and M. wengeri has been devised through cryopreservation of immature seeds. Immature seeds of both the species were precultured in 0.6 M Sucrose and 2 M Glycerol for 3 h at 24 ± 2 degree C. Precultured seeds were then desiccated under the airflow of 27 ± 3 m min -1 velocity inside laminar air flow cabinet for different time periods. The seeds were then cryostored in liquid nitrogen for an hour. A maximum of 40 percent and 36.6 percent seed germination was recorded after cryostorage at moisture contents of 26.0 percent and 16.2 percent for M. spathulata and M. wengeri respectively. To protect these rare plants against loss due to disease, insect damage, or natural disaster a back up collection has been established using the protocol and applied to a large number of immature seeds that were obtained from the ex situ plants growing in the experimental garden of the North-eastern Hill University, Shillong.

First-pass metabolism of 1,3-butadiene in once-through perfused livers of rats and mice.

First-pass metabolism of 1,3-butadiene (BD) leading to 1,2-epoxy-3-butene (EB), 1,2:3,4-diepoxybutane (DEB), 3-butene-1,2-diol (B-diol), 3,4-epoxy-1,2-butanediol (EBD) and crotonaldehyde (CA) was studied quantitatively in the once-through BD perfused liver of mouse and rat by means of an all-glass gas-tight perfusion system. Metabolites were analyzed using gas chromatography equipped with mass selective detection. The perfusate consisted of Krebs-Henseleit buffer (pH 7.4) containing bovine erythrocytes (40%v/v) and BD. The perfusion flow rates through the livers were 3-4 ml/min (mouse) and 17-20 ml/min (rat). The BD concentrations in the liver perfusates were 330 nmol/ml (mouse) and 240 nmol/ml (rat) being high enough to reach almost saturation of BD metabolism. The mean rates of BD transformation were about 0.014 and 0.055 mmol/h per liver of a mouse and a rat, respectively, being similar to the values expected from in-vivo measurements. There were marked species differences in the formation of BD metabolites. In the effluent of mouse livers, all three epoxides (EB: 9.4 nmol/ml; DEB: 0.06 nmol/ml; EBD: 0.07 nmol/ml) and B-diol (8.2 nmol/ml) were detected. In the perfusate leaving naïve rat livers, only EB and B-diol were found. In that of rat liver, EB concentration was 8.5 times smaller than in that of mouse liver, whereas B-diol concentrations were similar in the effluent liver perfusate of both species. CA was below the limit of its detection (60 nmol/l) in the liver perfusate of mice and of naïve rats. Of BD metabolized, the sum of the metabolites investigated in the effluent amounted to only 30% (mouse) and 20% (rat). In first experiments with rat liver, glutathione (GSH) was depleted by pretreating the animals with diethylmaleate. With the exception of EBD (not quantifiable due to an interfering peak), all other metabolites including CA were found in the effluent perfusate summing up to about 70 and 100% of BD metabolized, which indicates the quantitative importance of the GSH dependent metabolism. In summary, the results demonstrate the relevance of an intrahepatic first-pass metabolism for metabolic intermediates of BD, which undergo further transformation immediately after their production in the liver before leaving this organ. Hitherto, the occurrence of this first-pass metabolism was only hypothesized. The findings will help to explain the drastic species difference between mice and rats in the carcinogenic potency of BD.

Antagonistic effect of FePP on the ethanol mediated induction of hepatic, renal and splenic δ-amino levulinic acid synthase activityin vivo in rats.

In the current study, we report perturbations in hepatic, renal and splenic heme synthesis at the level of the rate limiting enzyme, δ-amino levulinic acid synthase (ALA-S) on ethanol administration independently and in conjunction with iron-protoporphyrin (FePP) in male Wistar rats. Excessive ethanol administration (5 ml/kg bw) resulted in a significant induction of hepatic, splenic and renal ALA-S activity. Simultaneous administration of FePP (50 µmol/kg bw) reverted the observed induction response to a sharp decline. The features of the action of ethanol and FePP togetherin vivo, i.e. a substantial inhibition of ALA-S is suggestive of the beneficial effects of this formulation in acute attacks of porphyria.

Evaluation of polymerase chain reaction for rapid diagnosis of clinically suspected tuberculous meningitis.

SETTING: Since conventional bacteriological methods rarely detect Mycobacterium tuberculosis in cerebrospinal fluid (CSF) and are of limited use in the diagnosis of tuberculous meningitis (TBM), clinical features suggestive of TBM supported by indirect evidence such as CSF examination and computerized tomography (CT) of the head have been used for the early diagnosis of TBM. OBJECTIVE: We evaluated the efficacy of polymerase chain reaction (PCR) in the diagnosis of TBM. METHODS: Coded CSF samples from 40 patients with TBM and from 49 patients with other neurological disorders were processed. In the absence of a reliable sensitive and specific test for M. tuberculosis in CSF, we used a set of established clinical criteria as the gold standard. Accordingly, the patients were divided into definite, highly probable, probable and possible TBM. The samples were decoded only after completion of the laboratory tests. RESULTS: PCR was positive in 2/4, 19/20, 13/16 patients with highly probable, probable and possible TBM respectively. None of the samples were positive by conventional bacteriological methods. However, 3/49 CSF samples from non-TBM patients were also found positive by PCR. PCR detected M. tuberculosis genomic DNA in the CSF of 85% of clinically suspected TBM cases and 6.1% of non-tuberculous controls. CONCLUSION: PCR, along with the suggested clinical criteria, offers a rapid and fairly accurate diagnosis of TBM.

Expression of keratins in mouse vaginal epithelium.

In the epithelium of the rodent vagina proliferation and differentiation are tightly regulated by ovarian hormones. Estrogens stimulate proliferation and squamous differentiation, whereas progesterone redirects differentiation to a mucus-secreting epithelium formed by goblet-like cells. In the present study, we used monospecific keratin antibodies to show the expression and distribution of keratins in SENCAR mouse vaginal epithelium in different stages of the estral cycle and in ovariectomized animals. In ovariectomized animals, the vaginal epithelium expressed K6, K8, K13 and K14, but not K1. After estrogen treatment, K1 was expressed. During proestrus and estrus, the keratin pattern was essentially identical to that observed in 17 beta-estradiol-stimulated animals. In contrast, during the progestational stages (metaestrus and diestrus) or after progesterone treatment of ovariectomized mice, the most relevant change was the loss of K1. Together, these results show that K1 expression is induced by estrogens in the vaginal epithelium. In contrast, K6, K8, K13 and K14 are constitutively expressed even when squamous differentiation is not observed.

Topical corticosteroids usage in dermatology.

Prescribing of topical corticosteroids was studied in 200 patients attending the dermatology outpatients, randomly auditing the written prescriptions. Data with regard to potency, quantity, frequency, duration and site of application was collected and analyzed. Potent topical steroids were commonly used in 86 (43%) patients. The quantity of topical steroid was mentioned in only 4% patients whereas the frequency was specified in 77%, the site in 69% and the duration in 55% patients, respectively. The importance of these parameters is discussed, guidelines regarding use of topical steroids suggested.

Drug use in dermatology.

Prescription of drugs was studied for 197 outpatients and 93 inpatients seeking treatment under the specialized services of the Dermatology Department of the Nehru Hospital attached to the Postgraduate Institute of Medical Education and Research, (PGIMER) Chandigarh. Disease patterns in both settings and drugs prescribed for them were analyzed from prescriptions, retrospectively. Brand drugs were prescribed to the tune of 60-65%, in both settings, some lacunae in prescription are discussed.

Drug usage in chest diseases.

A survey of prescribing trends was carried out on 70 admitted patients and 210 outpatients presenting themselves for treatment at the chest disease unit of the Nehru Hospital attached to the Postgraduate Institute of Medical Education and Research. Drug usage was found to be very rational and scientific, other findings are discussed.