Ecoinformatics using wireless sensor networks: An overview

Wireless sensor networks have the potential to become significant subsystems of ecological experiment. Sensor networks consist of large number of tiny sensor nodes, all of which have sensing capabilities. These networks allow coordinated signal detection, monitoring, and tracking to enable sensor nodes to simultaneously capture geographically distinct measurements. Sensor nodes do not require predetermined positioning making such networks especially useful for applications in remote, inhospitable environments. In this paper we have tried to see the various ecological experimental scenarios, and how wireless sensor networks can be used in that field. One of the most challenging bottlenecks in the usage of wireless sensor networks in large scale experiments is the energy constraint. Various routing protocols which have tried to optimize the energy usage are also studied in the paper.     

Stimulatory effects of Cuminum cyminum and flavonoid glycoside on Cyclosporine-A and restraint stress induced immune-suppression in Swiss albino mice

Many herbs and spices are known to modulate the immune system and have been shown to restore the immunity in immuno-compromised individuals. Spices generally used to increase the taste and flavor of food also has the history of usage as an ayurvedic medicine. Therefore to explore the health modulating effects of Cuminum cyminum and to identify the active compound, immunomodulatory properties were evaluated using flowcytometry and ELISA in normal and immune-suppressed animals. C. cyminum and compound 1 stimulated the T cells and Th1 cytokines expression in normal animals. Swiss albino mice subjected to Cyclosporine-A induced immune-suppression were dosed orally with C. cyminum (25, 50, 100 and 200 mg/kg) on consecutive days. The results showed that administration significantly increased T cells (CD4 and CD8) count and Th1 predominant immune response in a dose dependent manner thereby suggesting immunomodulatory activity through modulation of T lymphocytes expression. In restraint stress induced immune-suppressed animals, compound 1 countered the depleted T lymphocytes, decreased the elevated corticosterone levels and size of adrenal glands and increased the weight of thymus and spleen. Based on the data we may conclude that C. cyminum is a potent immunomodulator and may develop as a lead to recover the immunity of immuno-compromised individuals.     

Phytochemical and genetic analysis in selected chemotypes of Withania somnifera

The main active components and genetic profile of 15 selected accessions of Withania somnifera Dunal. were analysed. Ethanolic extract of the dried roots/leaves of the plant was concentrated under pressure at 50+/-5 degrees C and was analysed for main compounds (withanolides and withaferin A) by HPLC. All the main components were found to be present in accessions (AGB 002, AGB 009, RSS 009, RSS 033). Correlation of these main components with their genetic factors, was undertaken using AFLP (amplified fragment length polymorphism) markers. Among 64 primers 7 yielded optimum polymorphism. A total of 913 polymorphic peaks were generated using these primers. Jaccard's similarity coefficient indicated that accessions having almost the same active compounds clustered together. The present study demonstrates that AFLP can be successfully used to resolve the correlation of AFLP data with the presence of secondary metabolites.     

A gold nanoparticles based immuno-bioprobe for detection of Vi capsular polysaccharide of Salmonella enterica serovar Typhi

A rapid and sensitive gold-nanobioprobe based immunoassay format has been presented for the detection of capsular Vi polysaccharide of Salmonella enterica serovar Typhi (surface antigen) using anti-Vi antibodies. The Vi antigen was extracted from serovar Typhi cells, under the optimised growth conditions for its over-expression. Anti-Vi antibodies were produced and conjugated with gold nanoparticles (GNPs) of definite size (~30 nm), which served as the nano-bioprobe in the detection system. A sandwich immunoassay was developed using nitrocellulose dot blot comb (8/12 wells) membranes immobilized with anti-Salmonella antibodies at the optimal concentration (43 ng spot(-1)). The Vi antigen in the clinical isolates, spiked samples and also in the standard strain (serovar Typhi Ty2) was detected by measuring the colour intensity of GNPs and correlating it with the concentration of serovar Typhi in samples. Using this developed immunoassay technique Vi positive serovar Typhi strains could be detected with a sensitivity of up to 10(2) cells mL(-1) in the clinical isolates as well as in the spiked samples. The developed immunoassay technique could be useful for the detection of typhoid fever and may be important from an epidemiological point of view.     

First signature of islet beta-cell-derived naturally processed peptides selected by diabetogenic class II MHC molecules

The diversity of Ags targeted by T cells in autoimmune diabetes is unknown. In this study, we identify and characterize a limited number of naturally processed peptides from pancreatic islet beta-cells selected by diabetogenic I-A(g7) molecules of NOD mice. We used insulinomas transfected with the CIITA transactivator, which resulted in their expression of class II histocompatibility molecules and activation of diabetogenic CD4 T cells. Peptides bound to I-A(g7) were isolated and examined by mass spectrometry: some peptides derived from proteins present in secretory granules of endocrine cells, and a number were shared with cells of neuronal lineage. All proteins to which peptides were identified were expressed in beta cells from normal islets. Peptides bound to I-A(g7) molecules contained the favorable binding motif characterized by acidic amino acids at the P9 position. The draining pancreatic lymph nodes of prediabetic NOD mice contained CD4 T cells that recognized three different natural peptides. Furthermore, four different peptides elicited CD4 T cells, substantiating the presence of such self-reactive T cells. The overall strategy of identifying natural peptides from islet beta-cells opens up new avenues to evaluate the repertoire of self-reactive T cells and its role in onset of diabetes.     

A heat-activated MAP kinase (HAMK) as a mediator of heat shock response in tobacco cells

A heat-activated MAP kinase (HAMK), immunologically related to the extracellular signal-regulated kinase (ERK) super-family of protein kinases, has been identified in BY2 cells of tobacco. The activation of HAMK at 37 degrees C was transient and detected within 2 min and reached a maximum level within 5 min. Ca(2+) chelators and channel blockers, and the known inhibitors of MEK, a MAP kinase kinase, prevented the heat activation of HAMK. This suggests that HAMK activation is part of a heat-triggered MAP kinase cascade that requires Ca(2+) influx. The heat shock protein HSP70 accumulated at 37 degrees C, but not when HAMK activation was prevented with the inhibitors of MEK or with Ca(2+) chelators or channel blockers. As previously shown for heat activation of HAMK, heat-induced accumulation of HSP70 requires membrane fluidization and reorganization of cytoskeleton. We concluded that heat-triggered HAMK cascade might play an essential role in the launching of heat shock response and hsp gene expression in tobacco cells.     

Non-cell-autonomous effects of Ret deletion in early enteric neurogenesis

Neural crest cells (NCCs) form at the dorsal margin of the neural tube and migrate along distinct pathways throughout the vertebrate embryo to generate multiple cell types. A subpopulation of vagal NCCs invades the foregut and colonises the entire gastrointestinal tract to form the enteric nervous system (ENS). The colonisation of embryonic gut by NCCs has been studied extensively in chick embryos, and genetic studies in mice have identified genes crucial for ENS development, including Ret. Here, we have combined mouse embryo and organotypic gut culture to monitor and experimentally manipulate the progenitors of the ENS. Using this system, we demonstrate that lineally marked intestinal ENS progenitors from E11.5 mouse embryos grafted into the early vagal NCC pathway of E8.5 embryos colonise the entire length of the gastrointestinal tract. By contrast, similar progenitors transplanted into Ret-deficient host embryos are restricted to the proximal foregut. Our findings establish an experimental system that can be used to explore the interactions of NCCs with their cellular environment and reveal a previously unrecognised non-cell-autonomous effect of Ret deletion on ENS development.     

In APCs, the autologous peptides selected by the diabetogenic I-Ag7 molecule are unique and determined by the amino acid changes in the P9 pocket.

We demonstrate in this study the great degree of specificity in peptides selected by a class II MHC molecule during processing. In this specific case of the diabetogenic I-A(g7) molecule, the P9 pocket of I-A(g7) plays a critical role in determining the final outcome of epitope selection, a conclusion that is important in interpreting the role of this molecule in autoimmunity. Specifically, we examined the display of naturally processed peptides from APCs expressing either I-A(g7) molecules or a mutant I-A(g7) molecule in which the beta57Ser residue was changed to an Asp residue. Using mass spectrometry analysis, we identified over 50 naturally processed peptides selected by I-A(g7)-expressing APCs. Many peptides were selected as families with a core sequence and variable flanks. Peptides selected by I-A(g7) were unusually rich in the presence of acidic residues toward their C termini. Many peptides contained short sequences of two to three acidic residues. In binding analysis, we determined the core sequences of many peptides and the interaction of the acidic residues with the P9 pocket. However, different sets of peptides were isolated from APCs bearing a modified I-A(g7) molecule. These peptides did not favor acidic residues toward the carboxyl terminus.