Chidambaram, India
Chidambaram, India

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PubMed | University of New South Wales, Macquarie University, College Rd, Smithsonian Environmental Research Center and 4 more.
Type: | Journal: Scientific reports | Year: 2015

Strategies for managing biological invasions are often based on the premise that characteristics of invading species and the invaded environment are key predictors of the invaders distribution. Yet, for either biological traits or environmental characteristics to explain distribution, adequate time must have elapsed for species to spread to all potential habitats. We compiled and analyzed a database of natural history and ecological traits of 138 coastal marine invertebrate species, the environmental conditions at sites to which they have been introduced, and their date of first introduction. We found that time since introduction explained the largest fraction (20%) of the variability in non-native range size, while traits of the species and environmental variables had significant, but minimal, influence on non-native range size. The positive relationship between time since introduction and range size indicates that non-native marine invertebrate species are not at equilibrium and are still spreading, posing a major challenge for management of coastal ecosystems.


Davidson A.T.,Australian Antarctic Division | Davidson A.T.,University of Tasmania | McKinlay J.,Australian Antarctic Division | Westwood K.,Australian Antarctic Division | And 8 more authors.
Marine Ecology Progress Series | Year: 2016

The impacts of anthropogenic enhancement of the partial pressure of carbon dioxide (pCO2) on marine organisms remain unclear, especially in Antarctic waters, which are predicted to be amongst the earliest and most severely affected by the consequent changes in ocean chemistry. Marine microbes are the base of the Antarctic food chain, and the nature of their response to elevated pCO2 is important as they are key determinants of the biogeochemical cycles that affect global climate. We studied the response of a natural community of Antarctic marine microbes from near-shore waters off Davis Station, Antarctica, to pCO2 ranging from the concentration in the water column at the time the experiment began (ambient, 84 μatm) to that predicted by the year 2300 (2423 μatm) using 6 gas-tight, environmentally controlled tanks (minicosms; 650 l) to which CO2-saturated seawater was added. The microbial community showed little difference between 84 and 643 μatm CO2 (0.2 to 1.7 times present), indicating that they can tolerate the large seasonal range in pCO2 in Antarctic coastal waters. Concentrations ≤1281 μatm reduced the accumulation rate of chlorophyll and particulate carbon, changed the microbial community, and enhanced the relative abundance of small phytoplankton. If our results are indicative of the future responses of Antarctic marine microbes, elevated CO2 could profoundly affect the structure and function of the Antarctic food web by reducing the availability of food for higher trophic levels and decreasing the efficiency of the biological pump. © 2016 Inter-Research.


Tamilselvam K.,College Rd | Braidy N.,University of Sydney | Manivasagam T.,College Rd | Essa M.M.,Sultan Qaboos University | And 5 more authors.
Oxidative Medicine and Cellular Longevity | Year: 2013

Rotenone a widely used pesticide that inhibits mitochondrial complex I has been used to investigate the pathobiology of PD both in vitro and in vivo. Studies have shown that the neurotoxicity of rotenone may be related to its ability to generate reactive oxygen species (ROS), leading to neuronal apoptosis. The current study was carried out to investigate the neuroprotective effects of hesperidin, a citrus fruit flavanol, against rotenone-induced apoptosis in human neuroblastoma SK-N-SH cells. We assessed cell death, mitochondrial membrane potential, ROS generation, ATP levels, thiobarbituric acid reactive substances, reduced glutathione (GSH) levels, and the activity of catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) using well established assays. Apoptosis was determined in normal, rotenone, and hesperidin treated cells, by measuring the protein expression of cytochrome c (cyt c), caspases 3 and 9, Bax, and Bcl-2 using the standard western blotting technique. The apoptosis in rotenone-induced SK-N-SH cells was accompanied by the loss of mitochondrial membrane potential, increased ROS generation, the depletion of GSH, enhanced activities of enzymatic antioxidants, upregulation of Bax, cyt c, and caspases 3 and 9, and downregulation of Bcl-2, which were attenuated in the presence of hesperidin. Our data suggests that hesperidin exerts its neuroprotective effect against rotenone due to its antioxidant, maintenance of mitochondrial function, and antiapoptotic properties in a neuroblastoma cell line. © 2013 Kuppusamy Tamilselvam et al.


Kelly P.,HSE North West | Perry I.J.,College Rd
Irish Medical Journal | Year: 2011

We have carried out an audit of outcomes from a pre-school stammering intervention offered to all 64 children, aged under 5 years referred from a defined catchment population to a single speech and language therapist over an 11 year period (1993 -2003 inclusive). Therapy was based on a client centred eclectic approach which combines elements of direct therapy focused on the child s speech and a number of indirect approaches to treatment which focus on changing the child s environment. Follow-up was conducted by means of a short questionnaire to the parents. Non responders were assessed informally by a school nurse with responsibility for the clinic catchment area. Questionnaires were returned for 46 of the 64 children in the audit, of whom 43 were reported as not stammering, 2 with persistent stammer and there was one child with missing data on fluency status. No stammering was detected by the school nurse in the 2 8 non-respondents. Thus 62 of the 63 children (97%; 95% C.I. 88.9% to 99.6%) with documented fluency status were reported as free of stammer at follow-up. These outcomes exceed natural recovery rates and highlight the importance of early referral of children with pre-school stammering to a specialist speech and language clinic.


Rotenone a widely used pesticide that inhibits mitochondrial complex I has been used to investigate the pathobiology of PD both in vitro and in vivo. Studies have shown that the neurotoxicity of rotenone may be related to its ability to generate reactive oxygen species (ROS), leading to neuronal apoptosis. The current study was carried out to investigate the neuroprotective effects of hesperidin, a citrus fruit flavanol, against rotenone-induced apoptosis in human neuroblastoma SK-N-SH cells. We assessed cell death, mitochondrial membrane potential, ROS generation, ATP levels, thiobarbituric acid reactive substances, reduced glutathione (GSH) levels, and the activity of catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx) using well established assays. Apoptosis was determined in normal, rotenone, and hesperidin treated cells, by measuring the protein expression of cytochrome c (cyt c), caspases 3 and 9, Bax, and Bcl-2 using the standard western blotting technique. The apoptosis in rotenone-induced SK-N-SH cells was accompanied by the loss of mitochondrial membrane potential, increased ROS generation, the depletion of GSH, enhanced activities of enzymatic antioxidants, upregulation of Bax, cyt c, and caspases 3 and 9, and downregulation of Bcl-2, which were attenuated in the presence of hesperidin. Our data suggests that hesperidin exerts its neuroprotective effect against rotenone due to its antioxidant, maintenance of mitochondrial function, and antiapoptotic properties in a neuroblastoma cell line.


PubMed | College rd
Type: Journal Article | Journal: International journal of molecular sciences | Year: 2012

Domain III of the dengue virus envelope protein (EDIII, aa295-395) has an immunoglobulin fold and is the proposed receptor-binding domain of the virus. Previous studies have shown that monoclonal antibodies against EDIII can be neutralizing and have therapeutic potential. Here, cloned Fab-phage libraries of human and mouse origin were screened for DENV specific antibodies. Firstly, bacterially expressed EDIII or whole virus particles were used as bait in biopanning against a large nave human Fab-phage library (>10 billion independent clones). Multiple panning strategies were employed, and in excess of 1000 clones were screened, but all of the antibodies identified bound the envelope in regions outside EDIII suggesting EDIII antibodies are virtually absent from the nave human repertoire. Next, a chimeric Fab-phage library was constructed from a panel of EDIII specific mouse hybridomas by pooling the VH and VL chain sequences from the hybridomas and cloning these into the pComb3X phagemid vector with human CH and CL encoding sequences. Biopanning against EDIII identified a unique antibody (C9) that cross-reacts with EDIII from DENV1-3 and, in the IgG format, binds and neutralizes DENV2 in cell-based assays. Sequence analysis and saturation mutagenesis of complementary determining regions (CDR) in the C9 light chain suggest an antigen recognition model in which the LCDR3 is a key determinant of EDIII specificity, while modifications in LCDR1 and LCDR2 affect DENV serotype cross-reactivity. Overall, this study supports the current prevailing opinion that neutralizing anti-EDIII monoclonal antibodies can be readily generated in murine systems, but in humans the anti-DENV immune response is directed away from domain III.

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