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.     

Anticancer potential of Himalayan plants

Plants used in traditional medicine have stood up to the test of time and contributed many novel compounds for preventive and curative medicine to modern science. India is sitting on a gold mine of well recorded and traditionally well practiced knowledge of herbal medicine. Specially, plants growing at high altitude in Himalayan pastures are time-honored sources of health and general well being of local inhabitants. As of today, Himalayan plants are a major contributor to the herbal pharmaceutical industry both of India and other countries. Plants growing at higher altitudes are subjected to an assault of diverse testing situations including higher doses of mutagenic UV-radiation, physiological drought, desiccation and strong winds. Plants interact with stressful environments by physiological adaptation and altering the biochemical profile of plant tissues and producing a spectrum of secondary metabolites. Secondary metabolites are of special interest to scientists because of their unique pharmacophores and medicinal properties. Secondary metabolites like polyphenols, terpenes and alkaloids have been reported to possess antimutagenic and anticancer properties in many studies. The fundamental aspiration of the current review is to divulge the antimutagenic/anticancer potential of five alpine plants used as food or medicine by the populations living at high altitudes.     

Loss of p53 Ser18 and Atm results in embryonic lethality without cooperation in tumorigenesis

Phosphorylation at murine Serine 18 (human Serine 15) is a critical regulatory process for the tumor suppressor function of p53. p53Ser18 residue is a substrate for ataxia-telangiectasia mutated (ATM) and ATM-related (ATR) protein kinases. Studies of mice with a germ-line mutation that replaces Ser18 with Ala (p53(S18A) mice) have demonstrated that loss of phosphorylation of p53Ser18 leads to the development of tumors, including lymphomas, fibrosarcomas, leukemia and leiomyosarcomas. The predominant lymphoma is B-cell lymphoma, which is in contrast to the lymphomas observed in Atm(-/-) animals. This observation and the fact that multiple kinases phosphorylate p53Ser18 suggest Atm-independent tumor suppressive functions of p53Ser18. Therefore, in order to examine p53Ser18 function in relationship to ATM, we analyzed the lifespan and tumorigenesis of mice with combined mutations in p53Ser18 and Atm. Surprisingly, we observed no cooperation in survival and tumorigenesis in compound p53(S18A) and Atm(-/-) animals. However, we observed embryonic lethality in the compound mutant animals. In addition, the homozygous p53Ser18 mutant allele impacted the weight of Atm(-/-) animals. These studies examine the genetic interaction of p53Ser18 and Atm in vivo. Furthermore, these studies demonstrate a role of p53Ser18 in regulating embryonic survival and motor coordination.     

Virtual screening, identification and in vitro testing of novel inhibitors of O-acetyl-L-serine sulfhydrylase of Entamoeba histolytica

The explosive epidemicity of amoebiasis caused by the facultative gastrointestinal protozoan parasite Entamoeba histolytica is a major public health problem in developing countries. Multidrug resistance and side effects of various available antiamoebic drugs necessitate the design of novel antiamobeic agents. The cysteine biosynthetic pathway is the critical target for drug design due to its significance in the growth, survival and other cellular activities of E. histolytica. Here, we have screened 0.15 million natural compounds from the ZINC database against the active site of the EhOASS enzyme (PDB ID. 3BM5, 2PQM), whose structure we previously determined to 2.4 Å and 1.86 Å resolution. For this purpose, the incremental construction algorithm of GLIDE and the genetic algorithm of GOLD were used. We analyzed docking results for top ranking compounds using a consensus scoring function of X-Score to calculate the binding affinity and using ligplot to measure protein-ligand interactions. Fifteen compounds that possess good inhibitory activity against EhOASS active site were identified that may act as potential high affinity inhibitors. In vitro screening of a few commercially available compounds established their biological activity. The first ranked compound ZINC08931589 had a binding affinity of ∼8.05 µM and inhibited about 73% activity at 0.1 mM concentration, indicating good correlation between in silico prediction and in vitro inhibition studies. This compound is thus a good starting point for further development of strong inhibitors.     

Use of a Label-Free Quantitative Platform Based on MS/MS Average TIC to Calculate Dynamics of Protein Complexes in Insulin Signaling

A label-free quantification strategy including the development of in-house software (NakedQuant) to calculate the average TIC across all spectral counts in tandem affinity purification (TAP)-tagging liquid chromatography-mass spectrometry MS/MS (LC/MS/MS) experiments was applied to a large-scale study of protein complexes in the MAPK portion of the insulin signaling pathway from Drosophila cells. Dynamics were calculated under basal and stimulating conditions as fold changes. These experiments were performed in the context of a core service model with the user performing the TAP immunoprecipitation and the MS core performing the MS and informatics stops. The MS strategy showed excellent coverage of known components in addition to potentially novel interactions.     

In vitro selection of resistant/tolerant mutants lines of Citrus jambhiri Lush. using crude culture filtrate of Phytophthora parasitica and their randomly amplified polymorphic DNA analysis

This study deals with in vitro‐induced mutagenesis and selection of Phytophthora tolerant lines of Citrus jambhiri and their regeneration. For in vitro‐induced mutagenesis, cotyledons were treated with ethyl methane sulfonate (EMS) 100, 200 and 300 mm for different time durations viz. 1, 3, 6 and 9 hr. Callus cultures were established from EMS treated cotyledon explants on MS medium supplemented with 2.0 mg/L of 2,4‐D and 500 mg/L of malt extract. Calli derived from cotyledon were challenged in vitro on selective MS medium containing 5%–100% of culture filtrate (CF) of the Phytophthora parasitica. Selected mutagen‐treated calli showed resistance in vitro on media containing CF. Calli treated with 100 mm EMS for 6‐hr duration showed tolerance (24%) up to 75% CF after 4th selection cycle. While, calli treated with 200 mm for 6‐hr duration showed maximum tolerance (76%) up to 75% CF. Resistant calli were then transferred to MS regeneration medium for shoot bud regeneration. A dose‐dependent decrease in the regeneration capacity of the selected calli was observed with the increasing concentration of the CF. In randomly amplified polymorphic DNA analysis, plantlets showed different banding pattern in comparison with the control plant, which confirms the presence of variations at genetic level.     

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.     

Precise molecular weight determination of PCR products of the rRNA intergenic spacer region using electrospray quadrupole mass spectrometry for differentiation of B. subtilis and B. atrophaeus, closely related species of bacilli

Assessment of 16S–23S rRNA intergenic spacer region (ISR) sequence variability is an important supplement to 16S rRNA sequencing for differentiating closely related bacterial species. Species differentiation can also be achieved by determination of approximate size of PCR (polymerase chain reaction) products of ISRs, based on their relative electrophoretic mobility on agarose gels. Closely-related species can have ISR PCR products that are similar in size. More precise molecular weight (M.W.) determination of these products might allow improved discrimination of such species. Electrospray quadrupole mass spectrometry (ESI-Q-MS) has the potential to provide such precision. For ESI-Q-MS analysis, size limitation of PCR products is currently limited to around 130 base pairs (bp). Bacillus subtilis and Bacillus atrophaeus are two closely related species with few distinguishing phenotypic characteristics. B. subtilis has recently been sub-divided into two subgroups, W23 (type strain, W23) and 168 (type strain, 168). PCR products amplified from the ISR including the 5′ terminal end of the 23S rRNA and a conserved portion of the ISR were analyzed by ESI-Q-MS. A 119 or 120 bp PCR product was produced for B. atrophaeus strains. However, strains of B. subtilis subgroups W23 and 168 each produced 114 bp products. In summary, a mass spectrometry method was developed for differentiation of B. subtilis and B. atrophaeus. Also, the genetic similarity of B. subtilis subgroups W23 and 168 was confirmed. Accurate determination of the molecular weight of PCR products from the 16S–23S rRNA intergenic spacer region using electrospray quadrupole mass spectrometry has great potential as a general technique for characterizing closely related bacterial species.     

AXR2 encodes a member of the Aux/IAA protein family

The dominant gain-of-function axr2-1 mutation of Arabidopsis causes agravitropic root and shoot growth, a short hypocotyl and stem, and auxin-resistant root growth. We have cloned the AXR2 gene using a map-based approach, and find that it is the same as IAA7, a member of the IAA (indole-3-acetic acid) family of auxin-inducible genes. The axr2-1 mutation changes a single amino acid in conserved domain II of AXR2/IAA7. We isolated loss-of-function mutations in AXR2/IAA7 as intragenic suppressors of axr2-1 or in a screen for insertion mutations in IAA genes. A null mutant has a slightly longer hypocotyl than wild-type plants, indicating that AXR2/IAA7 controls development in light-grown seedlings, perhaps in concert with other gene products. Dark-grown axr2-1 mutant plants have short hypocotyls and make leaves, suggesting that activation of AXR2/IAA7 is sufficient to induce morphological responses normally elicited by light. Previously described semidominant mutations in two other Arabidopsis IAA genes cause some of the same phenotypes as axr2-1, but also cause distinct phenotypes. These results illustrate functional differences among members of the Arabidopsis IAA gene family.