Immobilization of Nickel by Bacterial Isolates from the Indian Ridge System and the Chemical Nature of the Accumulated Metal

Bacterial isolates from Carlsberg-Ridge waters were tested for their ability to immobilize Ni. For this, test cultures were suspended for 60 d in seawater with and without added Ni at concentrations of 10 to 10,000 μ M. At an initial concentration of 100 μ M, isolates CR35 and CR48 caused a 89.8 and 6.95 μ M decrease in dissolved Ni at 28 2°C and a 14.75 and 6.38 μ M at 3 1°C. Analyses showed the contribution of hydroxyl, carbonyl, sulfide and phosphoryl groups in Ni binding. The study proves that Ni immobilization can occur even in the absence of Mn and suggests their plausible role in the ridge ecosystem.     

A preliminary study of anaerobic thiosulfate‐oxidizing bacteria as denitrifiers in the Arabian Sea

Bacteria which oxidize thiosulfate and reduce nitrate (TONRB) and bacteria which oxidize thiosulfate and denitrify (TODB) sampled at 5‐, 100‐, 200‐ and 300‐m depths were enumerated in agar shake cultures by colony counting and by applying MPN technique, respectively. Lithotrophic denitrification was generally high at the surface but did not vary much with the distance from shore as indicated by the number of TODB. The number of TONRB shows that nitrate‐reduction was much higher at near‐shore stations. The low TODBITONRB ratios at intermediate depths and at 100 m show in particular that the relative abundance of these organisms could be one of the possible reasons for higher nitrite concentrations sometimes reported at these depths. Thiosulfate‐oxidizing and simultaneous nitrate‐reducing abilities of the isolates indicated that the strains isolated from near shore and surface waters were more active nitrate reducers than their counterparts in offshore or deeper waters. The growth yield values of these organisms ranged from 1.1 to 17.9 mg protein mmol^‐1 thiosulfate and from 11.7 to 36.3 mg protein mmol^‐1 sulfide and suggest that they could contribute to chemosynthetic production.     

Atherosclerotic cardiovascular disease and dermatomyositis: an analysis of the Nationwide Inpatient Sample survey

Introduction

Increased rates of cardiovascular disease are implicated in several rheumatologic diseases. Our aim was to characterize dermatomyositis hospitalizations and evaluate cardiovascular-associated mortality in this patient population.

Methods

We examined the frequency and mortality rates of several atherosclerotic cardiovascular diagnoses and procedures among hospitalized adult patients with dermatomyositis using data from the US Nationwide Inpatient Sample (NIS) from 1993 to 2007. We compared the odds of death among hospitalized dermatomyositis patients with each cardiovascular diagnosis or procedure to those without, as well as to controls with cardiovascular diagnoses, using logistic regression.

Results

A total of 50,322 hospitalizations of dermatomyositis patients occurred between 1993 and 2007 (mean age 58 years, and 73% female). Of all dermatomyositis hospitalizations, 20% were associated with a concurrent atherosclerotic cardiovascular diagnosis or procedure. The overall in-hospital mortality was 5.7%. Dermatomyositis patients with any associated atherosclerotic cardiovascular diagnosis or procedure were twice as likely to die during the inpatient stay compared to dermatomyositis patients who did not have atherosclerotic cardiovascular disease (OR = 2.0 95% CI 1.7-2.5, p < 0.0001). The odds ratio for death in patients with both dermatomyositis and cardiovascular disease compared to controls with cardiovascular disease alone was 1.98 (95% CI 1.57-2.48) in multivariate adjusted models.

Conclusions

Approximately one fifth of dermatomyositis hospitalizations in the US were associated with an atherosclerotic cardiovascular diagnosis or procedure. These patients have double the risk of in-hospital death in comparison with controls and dermatomyositis patients without a cardiovascular diagnosis, making identification of these groups important for both prognostic purposes and clinical care.     

Crosstalk between VEGF and novel angiogenic protein regulates tumor angiogenesis and contributes to aggressiveness of breast carcinoma

We have identified and characterized a novel proangiogenic glycoprotein (NAP) with molecular weight of 67 kDa from synovial fluid of rheumatoid arthritis patients. Proteomic analysis of the protein revealed 29% sequence coverage with maximum identity for human retinoblastoma binding protein 2. N-terminal amino acid sequence showed no identity to recently discovered protein sequences. NAP was also identified in both normal and tumor cell lines by Western blotting. NAP is a permeability factor as verified by miles permeability assay. The proangiogenic potential of NAP was identified using shell less CAM, rat cornea and tumor on CAM assays. NAP induces expression of VEGF and Flt-1 gene as verified by promoter reporter gene analysis. Further NAP induces proliferation of endothelial cells and formation of tube like structures. NAP is also involved in migration and invasion of tumor cells. Clinical data revealed the presence of NAP in breast cancer biopsies. We have developed monoclonal antibody (mAb), and specific ELISA, which confirmed the presence of NAP in the cytosol of tumor cells. The mAb effect was evaluated with established angiogenic assays. Further, we investigated the detailed mechanism by which NAP induces angiogenesis. NAP is phosphorylated by VEGF induced activation of MAPK and JNK pathways through VEGFR2 phosphorylation. NAP involves JNK pathway predominantly with further activation of NFκB in downstream processing of VEGF activation. Together these findings establish that NAP displays angiogenic properties and promotes efficient neovascularization both in vitro and in vivo models. These observations suggest that anti-NAP-mAb can be targeted for antiangiogenic therapy of cancer.     

Purification and characterization of butyrate-induced protein phosphatase involved in apoptosis of Ehrlich ascites tumor cells

Short chain fatty acids including butyrate exhibit wide variety of biological effects towards cell growth, morphology and gene expression. In this report, we study the mechanism by which butyrate (BuA) modulates the expression of protein phosphatase when treated to the cells. As a model system, we used Ehrlich Ascites Tumor (EAT) cells in which BuA-treatment induces expression of a protein phosphatase enzyme. Subsequently, BuA-induced protein phosphatase has been biochemically purified and characterized. Further, pretreatment of caspase-3 inhibitor abolished the activity of BuA-induced protein phosphatase indicating the involvement of caspase-3 in the activation of BuA-induced protein phosphatase. In addition, the relationship between BuA-induced protein phosphatase and apoptosis has been verified. Activation of endonuclease-II has been shown in BuA-treated EAT cells and that activity was completely inhibited by sodium orthovanadate, a tyrosine phosphatase inhibitor suggesting that endonuclease-II may serve as a possible down-stream target for BuA-induced protein phosphatase. Together, the data suggest that activation of protein phosphatase may be an early and essential step in BuA-mediated apoptotic signaling pathway in EAT cells.     

Synthesis and biological evaluation of anilino substituted pyrimidine linked pyrrolobenzodiazepines as potential anticancer agents

A series of new anilino substituted pyrimidine linked pyrrolo[2,1-c][1,4]benzodiazepine (PBD) conjugates were prepared and evaluated for their anticancer activity. The effects of four promising PBD conjugates on cell cycle of cancerous cell line A375 were investigated. These compounds showed the characteristic features of apoptosis like enhancement in the levels of p53, release of cytochrome c, and cleavage of PARP.     

Modulation of AP and DV signaling pathways by the homeotic gene Ultrabithorax during haltere development in Drosophila

Suppression of wing fate and specification of haltere fate in Drosophila by the homeotic gene Ultrabithorax is a classical example of Hox regulation of serial homology (Lewis, E.B. 1978. Nature 276, 565-570) and has served as a paradigm for understanding homeotic gene function. We have used DNA microarray analyses to identify potential targets of Ultrabithorax function during haltere specification. Expression patterns of 18 validated target genes and functional analyses of a subset of these genes suggest that down-regulation of both anterior-posterior and dorso-ventral signaling is critical for haltere fate specification. This is further confirmed by the observation that combined over-expression of Decapentaplegic and Vestigial is sufficient to override the effect of Ubx and cause dramatic haltere-to-wing transformations. Our results also demonstrate that analysis of the differential development of wing and haltere is a good assay system to identify novel regulators of key signaling pathways.     

Enhanced abundance of tintinnids under elevated CO<Subscript>2</Subscript> level from coastal Bay of Bengal

The role of microzooplankton (MZP) in the pelagic trophodynamics is highly significant, but the responses of marine MZP to increasing CO₂ levels are rather poorly understood. Hence the present study was undertaken to understand the responses of marine plankton to increasing CO₂ concentrations. Natural water samples from the coastal Bay of Bengal were incubated under the ambient condition and high CO₂ levels (703–711 μatm) for 5 days in May and June 2010. A significant negative correlation was obtained between phytoplankton and MZP abundance which indicated that phytoplankton community structure can considerably be controlled by MZP in this region. The average relative abundances of tintinnids under elevated CO₂ levels were found to be significantly higher (68.65 ± 5.63% in May; 85.46 ± 9.56% in June) than observed in the ambient condition (35.68 ± 6.83% in May; 79 ± 5.36% in June). The observed dominance of small chain forming diatom species probably played a crucial role as they can be potentially grazed by tintinnids. This fact was strengthened by the observed high negative correlations between the relative abundance of major phytoplankton and tintinnids. Moreover, particulate organic carbon and total bacterial counts were also enhanced under elevated CO₂ level and can serve as additional food source for ciliates. The observed responses of tintinnids to increasing CO₂ might have multiple impacts on the energy transfer, nutrient and carbon cycling in the coastal water. The duration of the present study was relatively short and therefore further investigation on longer time scale needs to be done and might give us a better insight about phytoplankton and MZP species succession under elevated CO₂ level.     

Biochemical properties of pigeon milk and its effect on growth

Summary The avian juvenile food pigeon milk was studied for its chemical composition and effect on growth in vivo and in vitro. Pigeon milk on a wet weight basis consisted of 9–13% protein, 9–11% fat, 0.9–1.5% carbohydrate, 0.8–1.1% ash, 0.10–0.12% non-protein nitrogen, energy content 5.6–6.8 kcal·g^-1. Except for proteins there was little or no decrease in pigeon milk constitutents during the first week of secretion. Pigeon milk proteins consisted of trichloroacetic acid (precipitable), trichloroacetic acid (soluble), and free amino acid components in the ranges 8.4–12.1%, 0.5–0.7% and 1.4–2.5%, respectively; whereas the level of trichloroacetic acid (precipitable) and trichloroacetic acid (soluble) components decreased by about 30%, that of the free amino acids increased by 9% in the first week. About 0.6–1.0% of pigeon milk sugar was found in the trichloroacetic acid (soluble) fraction and increased by 67% in the first week. The remainder was found in the trichloroacetic acid (precipitable) fraction and did not change during this period. Major lipids of pigeon milk were the neutral lipids (7.8–8.4%); the minor lipids were glycolipids (0.9–1.6%), phospholipids (0.5–1.4%) and cholesterol (0.5–0.6%). Squabs fed pigeon milk increased their body weight by 22-fold in the first 3 weeks after hatching, and crude extracts of pigeon milk stimulated the growth of cultured hamster ovary cells. These results reflect the ability of pigeon milk to stimulate growth both in vivo and in vitro.Abbreviations AOAC association of official analytical chemists - BRIT board of radiation and isotope technology - CHO chinese hamster ovary - DNA deoxyribonucleic acid - EDTA ethylenediaminetetra-acetic acid - FCS foetal calf serum - GF growth factor - GS goat serum - MEM minimum essential medium - NPN nonprotein nitrogen - PBS phosphate-buffered saline - PM pigeon milk - TCA(P) trichloroacetic acid precipitable fraction - TCA(S) trichloroacetic acid soluble fraction