Biodegradation of vinyl chloride and cis-dichloroethene by a Ralstonia sp. strain TRW-1

An aerobic bacterium, Ralstonia sp. strain TRW-1, that assimilates vinyl chloride (VC) or ethene (ETH) as the sole carbon source was isolated from a chloroethene-degrading enrichment culture. Phylogenetic analysis of 16S rDNA sequence of the isolate revealed almost 99% sequence similarity to Ralstonia pickettii. To our knowledge, this is the first report describing the isolation of a member of Ralstonia that can degrade VC as the growth substrate. The measured growth yield values for VC and ETH were 11.27 and 18.90 g protein/mole, respectively. The estimated half-velocity constant K _m values for VC and ETH were 9.09±2.97 and 5.73±2.96 μM, respectively. These values are almost three- to tenfold higher than for other VC-assimilating Mycobacterium sp. The strain also degrades cis-dichloroethene (cis-DCE) in mineral salts medium containing yeast-extract, beef-extract, casamino acids, or peptone. This ability of the strain TRW-1 to degrade cis-DCE in the presence of a nontoxic, water-soluble substrate is relevant to in-situ remediation of cis-DCE-contaminated aquifers.     

Fluorescence studies on the interaction of choline-binding domain B of the major bovine seminal plasma protein,PDC-109 with phospholipid membranes

The microenvironment and accessibility of the tryptophan residues in domain B of PDC-109 (PDC-109/B) in the native state and upon ligand binding have been investigated by fluorescence quenching, time-resolved fluorescence and red-edge excitation shift (REES) studies. The increase in the intrinsic fluorescence emission intensity of PDC-109/B upon binding to lysophosphatidylcholine (Lyso-PC) micelles and dimyristoylphosphatidylcholine (DMPC) membranes was considerably less as compared to that observed with the whole PDC-109 protein. The degree of quenching achieved by different quenchers with PDC-109/B bound to Lyso-PC and DMPC membranes was significantly higher as compared to the full PDC-109 protein, indicating that membrane binding afforded considerably lesser protection to the tryptophan residues of domain B as compared to those in the full PDC-109 protein. Finally, changes in red-edge excitation shift (REES) seen with PDC-109/B upon binding to DMPC membranes and Lyso-PC micelles were smaller that the corresponding changes in the REES values observed for the full PDC-109. These results, taken together suggest that intact PDC-109 penetrates deeper into the hydrophobic parts of the membrane as compared to domain B alone, which could be the reason for the inability of PDC-109/B to induce cholesterol efflux, despite its ability to recognize choline phospholipids at the membrane surface.     

Antimalarial and antileishmanial activities of histone deacetylase inhibitors with triazole-linked cap group

Histone deacetylase inhibitors (HDACi) are endowed with plethora of biological functions including anti-proliferative, anti-inflammatory, anti-parasitic, and cognition-enhancing activities. Parsing the structure–activity relationship (SAR) for each disease condition is vital for long-term therapeutic applications of HDACi. We report in the present study specific cap group substitution patterns and spacer-group chain lengths that enhance the antimalarial and antileishmanial activity of aryltriazolylhydroxamates-based HDACi. We identified many compounds that are several folds selectively cytotoxic to the plasmodium parasites compared to standard HDACi. Also, a few of these compounds have antileishmanial activity that rivals that of miltefosine, the only currently available oral agent against visceral leishmaniasis. The anti-parasite properties of several of these compounds tracked well with their anti-HDAC activities. The results presented here provide further evidence on the suitability of HDAC inhibition as a viable therapeutic option to curb infections caused by apicomplexan protozoans and trypanosomatids.     

Cumulative funnel plots for the early detection of interoperator variation: retrospective database analysis of observed versus predicted results of percutaneous coronary intervention

Objective To use funnel plots and cumulative funnel plots to compare in-hospital outcome data for operators undertaking percutaneous coronary interventions with predicted results derived from a validated risk score to allow for early detection of variation in performance.Design Analysis of prospectively collected data.Setting Tertiary centre NHS hospital in the north east of England.Participants Five cardiologists carrying out percutaneous coronary interventions between January 2003 and December 2006.Main outcome measures In-hospital major adverse cardiovascular and cerebrovascular events (in-hospital death, Q wave myocardial infarction, emergency coronary artery bypass graft surgery, and cerebrovascular accident) analysed against the logistic north west quality improvement programme predicted risk, for each operator. Results are displayed as funnel plots summarising overall performance for each operator and cumulative funnel plots for an individual operator’s performance on a case series basis.Results The funnel plots for 5198 patients undergoing percutaneous coronary interventions showed an average observed rate for major adverse cardiovascular and cerebrovascular events of 1.96% overall. This was below the predicted risk of 2.06% by the logistic north west quality improvement programme risk score. Rates of in-hospital major adverse cardiovascular and cerebrovascular events for all operators were within the 3σ upper control limit of 2.75% and 2σ upper warning limit of 2.49%.Conclusion The overall in-hospital major adverse cardiovascular and cerebrovascular events rates were under the predicted event rate. In-hospital rates after percutaneous coronary intervention procedure can be monitored successfully using funnel and cumulative funnel plots with 3σ control limits to display and publish each operator’s outcomes. The upper warning limit (2σ control limit) could be used for internal monitoring. The main advantage of these charts is their transparency, as they show observed and predicted events separately. By this approach individual operators can monitor their own performance, using the predicted risk for their patients but in a way that is compatible with benchmarking to colleagues, encapsulated by the funnel plot. This methodology is applicable regardless of variations in individual operator case volume and case mix.     

Proinflammatory cytokines dominate the early immune response to filarial parasites

Although the early human immune response to the infective-stage larvae (L3) of Brugia malayi has not been well-characterized in vivo (because of the inability to determine the precise time of infection), the consensus has been that it must involve a predominant Th2 environment. We have set up an in vitro system to study this early immune response by culturing PBMC from unexposed individuals with live L3 of B. malayi. After 24 h of culture, T cell responses were examined by flow cytometry and by quantitative real-time RT-PCR for multiple cytokines. T cells were activated early following exposure to L3 as indicated by up-regulation of surface markers CD69 and CD71. The frequency of T cells expressing proinflammatory Th1 cytokines (IFN-gamma, TNF-alpha, GM-CSF, IL-1alpha, and IL-8) but not Th2 cytokines (IL-4, IL-5, IL-6, IL-10, and IL-13) was significantly increased in response to L3. This T cell response occurred in both the CD4 and CD8 T cell compartment and was restricted to the effector/memory pool (CD45RO(+)). This T cell response was not due to LPS activity from the parasite or from its endosymbiont, Wolbachia; moreover, it required the presence of APC as well as direct contact with live L3. Real-time RT-PCR analysis of multiple cytokines in the T cells confirmed the increased expression of proinflammatory Th1 cytokines. Up-regulation of these cytokines suggests that the primary immune response to the live infective stage of the parasite is not predominantly Th2 in nature but rather dominated by a proinflammatory response.     

Isolation, purification and characterization of collagenase from hepatopancreas of the land snail Achatina fulica

Collagenase (matrix metalloproteinase-1, EC:3.4.24.7) was isolated from the hepatopancreas of Achatina fulica and characterized for its enzymatic activity and immunological properties. Procollagenase was isolated using ammonium sulphate precipitation and gel filtration, followed by purification by reverse-phase high performance liquid chromatography in the presence of trifluoroacetic acid and by dialysis in neutral buffer. In the presence of SDS and beta-mercaptoethanol, the procollagenase resolved into two subunits with molecular masses of 63 and 28 kDa, respectively. The 63 kDa fragment retained its ability to bind and degrade gelatin, but the 28 kDa was inactive. Analysis by 2D gel electrophoresis revealed that the 63 kDa fragment was basic (pIs 7.6, 7.8 and 8.15), while the 28 kDa fragment was acidic (pI 4.7 and 5.1). Western blot analysis confirmed the identity of collagenase, as only matrix metalloproteinase-1 rabbit antibodies against human matrix metalloproteinase-1 (N-terminal region) recognized both the isolated procollagenase and the 63 kDa fragment.     

Effect of long term starvation on the biochemical composition of the muscles and hepatopancreas in the crab Menippe rumphii (Fabricius) (Crustacea: Brachyura)

During the process of long term starvation both muscles and hepatopancreas are affected in their biochemical composition at different rates. During early days of starvation an increase in the muscular and hepatopancreatic glycogen is observed. At the same time a simultaneous decrease in the muscular lipid content is also observed. At a slightly later period a decrease in the hepatopancreatic lipid content is also noticed. This amount of decrease is slow in the early days of starvation and rapid in later days. Decrease in the muscular and hepatopancreatic protein content is observed when there is not an adequate quantity of hepatopancreatic lipid to be consumed.     

Synthesis, antimalarial, antileishmanial, antimicrobial, cytotoxicity, and methemoglobin (MetHB) formation activities of new 8-quinolinamines

We report the synthesis, in vitro antiprotozoal (against Plasmodium and Leishmania), antimicrobial, cytotoxicity (Vero and MetHb-producing properties), and in vivo antimalarial activities of two series of 8-quinolinamines. N1-{4-[2-(tert-Butyl)-6-methoxy-8-quinolylamino]pentyl}-(2S/2R)-2-aminosubstitutedamides (21-33) and N1-[4-(4-ethyl-6-methoxy-5-pentyloxy-8-quinolylamino)pentyl]-(2S/2R)-2-aminosubstitutedamides (51-63) were synthesized in six steps from 6-methoxy-8-nitroquinoline and 4-methoxy-2-nitro-5-pentyloxyaniline, respectively. Several analogs displayed promising antimalarial activity in vitro against Plasmodium falciparum D6 (chloroquine-sensitive) and W2 (chloroquine-resistant) clones with high selectivity indices versus mammalian cells. The most promising analogs (21-24) also displayed potent antimalarial activity in vivo in a Plasmodium berghei-infected mouse model. Most interestingly, many analogs exhibited promising in vitro antileishmanial activity against Leishmania donovani promastigotes, and antimicrobial activities against a panel of pathogenic bacteria and fungi. Several analogs, notably 21-24, 26-32, and 60, showed less MetHb formation compared to primaquine indicating the potential of these compounds in 8-quinolinamine-based antimalarial drug development.     

Sequence Analysis of 16S rRNA and secA Genes Confirms the Association of 16SrI‐B Subgroup Phytoplasma with Oil Palm (Elaeis guineensis Jacq.) Stunting Disease in India

During January 2010, severe stunting symptoms were observed in clonally propagated oil palm (Elaeis guineensis Jacq.) in West Godavari district, Andhra Pradesh, India. Leaf samples of symptomatic oil palms were collected, and the presence of phytoplasma was confirmed by nested polymerase chain reaction (PCR) using universal phytoplasma‐specific primer pairs P1/P7 followed by R16F2n/R16R2 for amplification of the 16S rRNA gene and semi‐nested PCR using universal phytoplasma‐specific primer pairs SecAfor1/SecArev3 followed by SecAfor2/SecArev3 for amplification of a part of the secA gene. Sequencing and BLAST analysis of the ～1.25 kb and ～480 bp of 16S rDNA and secA gene fragments indicated that the phytoplasma associated with oil palm stunting (OPS) disease was identical to 16SrI aster yellows group phytoplasma. Further characterization of the phytoplasma by in silico restriction enzyme digestion of 16S rDNA and virtual gel plotting of sequenced 16S rDNA of ～1.25 kb using iPhyClassifier online tool indicated that OPS phytoplasma is a member of 16SrI‐B subgroup and is a ‘Candidatus Phytoplasma asteris’‐related strain. Phylogenetic analysis of 16S rDNA and secA of OPS phytoplasma also grouped it with 16SrI‐B. This is the first report of association of phytoplasma of the 16SrI‐B subgroup phytoplasma with oil palm in the world.     

Pregnane glycosides from Caralluma adscendens var. fimbriata

Eleven novel pregnane glycosides, 2-7 and 9-13, of which four, i.e., 10-13, comprised a new pregnane-type genin exhibiting a hydroxymethylene instead of a Me group at C(19), and the known pregnane glycoside stalagmoside V (8) were isolated from whole plants of Caralluma adscendens var. fimbriata, a native Indian succulent plant. Their structures were elucidated by extensive 2D-NMR spectroscopic studies.