Physiological characterization and stress-induced metabolic responses of Dunaliella salina isolated from salt pan

A Dunaliella strain was isolated from salt crystals obtained from experimental salt farm of the institute (latitude 21.46 N, longitude 72.11 degrees E). The comparative homology study of amplified molecular signature 18S rRNA, proves the isolated strain as D. salina. The growth pattern and metabolic responses such as proline, glycine betaine, glycerol, total protein and total sugar content to different salinity (from 0.5 to 5.5 M NaCl) were studied. The optimum growth was observed at 1.0 M NaCl and thereafter it started to decline. Maximum growth was obtained on 17th day of inoculation in all salt concentrations except 0.5 M NaCl, whereas maximum growth was observed on 13th day. There were no significant differences (P < 0.01) in chlorophyll a/b contents (1.0-1.16 +/- 0.05 mug chl. a and 0.2-0.29 +/- 0.01 mug chl. b per 10(6) cells) up to 2.0 M NaCl, however at 3.0 M NaCl a significant increase (2.5 +/- 0.12 mug chl. a and 0.84 +/- 0.4 mug chl. b per 10(6) cells) was observed which declined again at 5.5 M NaCl concentration (2.0 +/- 0.1 mug chl. a and 0.52 +/- 0.03 mug chl. b per 10(6) cells). Stress metabolites such as proline, glycine betaine, glycerol and total sugar content increased concomitantly with salt concentration. Maximum increase in proline (1.4 +/- 0.07 mug), glycine betaine (5.7 +/- 0.28 mug), glycerol (3.7 +/- 0.18 ml) and total sugar (250 +/- 12.5 mug) per 10(5) cells was observed in 5.5 M NaCl. A decrease in total protein with reference to 0.5 M NaCl was observed up to 3.0 M NaCl, however, a significant increase (P < 0.01) was observed at 5.5 M NaCl (0.19 +/- 0.01 mug per 10(5) cells). Inductive coupled plasma (ICP) analysis shows that intracellular Na(+) remained unchanged up to 2.0 M NaCl concentration and thereafter a significant increase was observed. No relevant increase in the intracellular level of K(+) and Mg(++) was observed with increasing salt concentration. Evaluation of physiological and metabolic attributes of Dunaliella salina can be used to explore its biotechnological and industrial potential.     

Solubility Enhancement of Lovastatin by Modified Locust Bean Gum Using Solid Dispersion Techniques

The aim of the present study was to improve the solubility of poorly water soluble drug lovastatin (LS) by solid dispersion (SD) techniques using modified locust bean gum (MLBG) as a carrier. The locust bean gum (LBG) was modified by heating and there observed irreversible decrease in viscosity, whereas swelling property remains unaffected. The advantage of modification of LBG was illustrated by difference in dissolution profiles of their SD. Effect of polymer concentration and methods of preparation on solubility enhancement were studied using solubility and dissolution studies, respectively. The result of solubility study showed increase in solubility of LS with increase in concentration of MLBG. It was found that the dissolution rate of LS from its SD was dependent on the method of preparation of solid dispersions. Dissolution study revealed that the modified solvent evaporation is most convenient and effective method for solubility enhancement of poorly water soluble drug LS, among various methods of preparation of SD. The prepared SDs were characterized by differential scanning calorimetry, scanning electron microscopy, and X-ray diffraction study. In vivo study was performed by measuring 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG Co-A) reductase inhibition activity. Significant reduction in HMG Co-A reductase activity was observed in case of solid dispersions of LS than plain LS. In conclusion, MLBG could be used as a potential carrier in enhancing the dissolution rate and bioavailability of LS.     

Plasma IP-10, apoptotic and angiogenic factors associated with fatal cerebral malaria in India

Background

Knowledge on insecticide resistance in target species is a basic requirement to guide insecticide use in malaria control programmes. Malaria transmission in the Mekong region is mainly concentrated in forested areas along the country borders, so that decisions on insecticide use should ideally be made at regional level. Consequently, cross-country monitoring of insecticide resistance is indispensable to acquire comparable baseline data on insecticide resistance.

Methods

A network for the monitoring of insecticide resistance, MALVECASIA, was set up in the Mekong region in order to assess the insecticide resistance status of the major malaria vectors in Cambodia, Laos, Thailand, and Vietnam. From 2003 till 2005, bioassays were performed on adult mosquitoes using the standard WHO susceptibility test with diagnostic concentrations of permethrin 0.75% and DDT 4%. Additional tests were done with pyrethroid insecticides applied by the different national malaria control programmes.

Results

Anopheles dirus s.s., the main vector in forested malaria foci, was susceptible to permethrin. However, in central Vietnam, it showed possible resistance to type II pyrethroids. In the Mekong delta, Anopheles epiroticus was highly resistant to all pyrethroid insecticides tested. It was susceptible to DDT, except near Ho Chi Minh City where it showed possible DDT resistance. In Vietnam, pyrethroid susceptible and tolerant Anopheles minimus s.l. populations were found, whereas An. minimus s.l. from Cambodia, Laos and Thailand were susceptible. Only two An. minimus s.l. populations showed DDT tolerance. Anopheles vagus was found resistant to DDT and to several pyrethroids in Vietnam and Cambodia.

Conclusion

This is the first large scale, cross-country survey of insecticide resistance in Anopheles species in the Mekong Region. A unique baseline data on insecticide resistance for the Mekong region is now available, which enables the follow-up of trends in susceptibility status in the region and which will serve as the basis for further resistance management. Large differences in insecticide resistance status were observed among species and countries. In Vietnam, insecticide resistance was mainly observed in low or transmission-free areas, hence an immediate change of malaria vector control strategy is not required. Though, resistance management is important because the risk of migration of mosquitoes carrying resistance genes from non-endemic to endemic areas. Moreover, trends in resistance status should be carefully monitored and the impact of existing vector control tools on resistant populations should be assessed.     

The influence of alkali pretreatments in lyocell resin finishing – Fiber structure

The fiber structure was investigated in lyocell fabrics treated with NaOH (120 g/l), or KOH (250 g/l), and compared with that in untreated fabrics. The alkali treatments caused some degree of degradation in fibers, but no significant changes in carboxyl contents or crystallinity. There were indications of transitions of porosity in the morphology of lyocell fibers, with accessibility at the fiber centers being distinctly lower than that at the outer edges. Both alkali treatments appeared to increase accessibility at the peripheral region in fibers, though to different extents; but there were no evident changes of accessibility at fiber centers. A model is proposed of changes in fiber structure due to the two alkali treatments.     

Synthesis and biological evaluation of indolyl bisphosphonates as anti-bone resorptive and anti-leishmanial agents

A series of indole conjugated bisphosphonate derivatives have been synthesized and evaluated for their in vitro anti-bone resorptive activity using bone marrow osteoclast culture. Two bisphosphonates 23 and 24 significantly inhibited osteoclastogenesis, 23 showed inhibition at 10 and 100 pM which was lower than the concentration of standard drug alendronate, and 24 inhibited osteoclastogenesis at 100 nM which was comparable to alendronate. Two other compounds 13 and 14 also showed inhibition comparable to alendronate, but were cytotoxic in the osteoblast cells. The two active bisphosphonates 23 and 24 induced significant osteoclast apoptosis at concentrations 100 nM for compound 24 and at 10 pM for compound 23 compared to alendronate. In vivo effect of active bisphosphonates 23 and 24 resulted in osteoclastogenesis of bone marrow cells (BMCs) to almost 40-50% (23 showing 8.4% decrease and 24 showing 9.0%) compared to 16.5% of the ovariectomized group. Further, screening of anti-leishmanial activity, four compounds 24-25 and 27-28 showed more than 80% inhibition against both the promastigote and amastigote stages of the Leishmania parasite.     

PCR based molecular technique for identification and discrimination of quarantined and non-quarantined Tilletia sps

Polymerase chain reaction (PCR) based RAPD profiles, in conjunction with six primers, of Karnal bunt of wheat and rice bunt exhibiting distinct polymorphic DNA. A total of 84 RAPD loci were observed on polyacrylamide gel for both Tilletia sps. Out of 84, 16 loci were found monomorphic, while other 68 loci were unique. Usefulness of random primers was also checked with other seed borne fungal pathogens of wheat and rice. None of primers gave amplification with Magnaporthe grisea, a causative agent of rice blast. However, distinct RAPD profiles were obtained with Alternaria triticina, Fusarium monaliforme, Helminthosporium sativum and Rhizoctonia solani. These six arbitrary primers could distinguish T. indica, a quarantine fungal pathogen from a non-quarantine fungal pathogen, T. barclayana. The two Tilletia sps. could be discriminated not only on the basis of distinct RAPD profiles, but also by presence of few unique gene fragments amplified using all six primers.     

Biodegradation and in vivo biocompatibility of rosin: a natural film-forming polymer

The specific aim of the present study was to investigate the biodegradation and biocompatibility characteristics of rosin, a natural film-forming polymer. Both in vitro as well as in vivo methods were used for assessment of the same. The in vitro degradation of rosin films was followed in pH 7.4 phosphate buffered saline at 37°C and in vivo by subdermal implantation in rats for up to 90 days. Initial biocompatibility was followed on postoperative days 7, 14, 21, and 28 by histological observations of the surrounding tissues around the implanted films. Poly (DL-lactic-co-glycolic acid) (PLGA) (50∶50) was used as reference material for biocompatibility. Rate and extent of degradation were followed in terms of dry film weight loss, molecular weight (MW) decline, and surface morphological changes. Although the rate of in vitro degradation was slow, rosin-free films showed complete degradation between 60 and 90 days following subdermal implantation in rats. The films degraded following different rates, in vitro and in vivo, but the mechanism followed was primarily bulk degradation. Rosin films demonstrated inflammatory reactions similar to PLGA, indicative of good biocompatibility. Good biocompatibility comparable to PLGA is demonstrated by the absence of necrosis or abscess formation in the surrounding tissues. The study provides valuable insight, which may lead to new applications of rosin in the field of drug delivery.     

Comparing the success of different prediction software in sequence analysis: a review

The abundance of computer software for different types of prediction in DNA and protein sequence analyses raises the problem of adequate ranking of prediction program quality. A single measure of success of predictor software, which adequately ranks the predictors, does not exist. A typical example of such an incomplete measure is the so-called correlation coefficient. This paper provides an overview and short analysis of several different measures of prediction quality. Frequently, some of these measures give results contradictory to each other even when they relate to the same prediction scores.This may lead to confusion. In order to overcome some of the problems, a few new measures are proposed including some variants of a 'generalised distance from the ideal predictor score'; these are based on topological properties, rather than on statistics. In order to provide a sort of a balanced ranking, the averaged score measure (ASM) is introduced.The ASM provides a possibility for the selection of the predictor that probably has the best overall performance.The method presented in the paper applies to the ranking problem of any prediction software whose results can be properly represented in a true positive-false positive framework, thus providing a natural set-up for linear biological sequence analysis.     

Growth suppression of human transformed cells by treatment with bark extracts from a medicinal plant, Terminalia arjuna

Summary We have investigated the effects of acetone and methanol extracts of a medicinal plant, Terminalia arjuna, on the growth of human normal fibroblasts (WI-38), osteosarcoma (U2OS), and glioblastoma (U251) cells in vitro. We found that both extracts at 30 μg and 60 μg/ml concentrations inhibit the growth of transformed cells; the growth of normal cells was least affected. Although the transformed cells appeared to have fragmented nucleus by Hoechst staining, no deoxyribonucleic acid laddering effect was observed. In response to the extract treatment, the tumor suppressor protein, p53, was induced in U2OS but not in U251 and WI-38 cells. A cyclin-dependent kinase inhibitor, p21^WAF1, was induced in transformed cells only. The study suggests that the bark extract of medicinal plant, T. arjuna, has components that can induce growth arrest of transformed cells by p53-dependent and-independent pathways.