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1.
KV Thomas 《Biofouling》2013,29(1):73-86
Antifouling paint booster biocides are a group of organic compounds added to antifouling paints to improve their efficacy. They have become prevalent since the requirement for alternative antifouling paints formulations for small boats (< 25 m). This need followed a ban on the use of triorganotin biocides in antifouling paints for small boats, in the late 1980's. Worldwide, around eighteen compounds are currently used as antifouling biocides, viz. benzmethylamide, chlorothalonil, copper pyrithione, dichlofluanid, diuron, fluorofolpet, Irgarol 1051, Sea‐Nine 211, Mancozeb, Polyphase, pyridine‐triphenyl‐borane, TCMS (2,3,5,6‐tetrachloro‐4‐methylsulfonyl) pyridine, TCMTB [2‐(thiocyanomethylthio)benzothia‐zole], Thiram, tolyfluanid, zinc pyrithione (ZPT), ziram and Zineb. Any booster biocide released into the environment is subjected to a complex set of processes. These processes include transport mechanisms, transformation, degradation, cross media partitioning, and bioaccumulation. This paper reviews the fate and behaviour data currently available in the public domain concerning antifouling paint booster biocides. 相似文献
2.
Steroid hormones play a key role in the beginning, development and termination of gestation. This reveiw is devoted for physiological effects of estrogens, progesterone, cortisole, ACTH, CRH in various pregnancy events: implantation, fetus development, maternal adaptation and birth initiation. Priority is fixed for estrogens--steroids that vastly increase maternal circulating blood value, induce progesterone action on uterus, regulate fetal "hypothalamic-pituitary-adrenocortical" axis, control free cortisole level in feminine blood. Diagnostic criterions of steroid hormone determination durijng pregnancy are presented. To day unconjugated estriol is the only steroid hormone that implicated in total pregnancy screening programs. Its concentration reduction has been noted in pregnancies with Dawn syndrome, some child enzyme defetcs, intrauterine growth retardation and fetal death incidents. 相似文献
3.
Background
The function of proteins is a direct consequence of their three-dimensional structure. The structural classification of proteins describes the ways of folding patterns all proteins could adopt. Although, the protein folds were described in many ways the functional properties of individual folds were not studied.Results
We have analyzed two β-barrel folds generally adopted by small proteins to be looking similar but have different topology. On the basis of the topology they could be divided into two different folds named SH3-fold and OB-fold. There was no sequence homology between any of the proteins considered. The sequence diversity and loop variability was found to be important for various binding functions.Conclusions
The function of Oligonucleotide/oligosaccharide-binding (OB) fold proteins was restricted to either DNA/RNA binding or sugar binding whereas the Src homology 3 (SH3) domain like proteins bind to a variety of ligands through loop modulations. A question was raised whether the evolution of these two folds was through DNA shuffling. 相似文献4.
Basavegowdanadoddi Marinaik Chandranaik Sonnahallipura Munivenkatappa Byregowda Mudalagiri Dasappagupta Venkatesha Kantharajapura Ramanna Ramesha Poojappa Nandini Poorvi Reddy Thushara Bindu KV Beechagondahalli Papanna Shivashankar Byadarahalli Puttaswamy Shankar Methuku Sobha Rani 《European Journal of Wildlife Research》2018,64(1):4
We report the molecular epidemiology of highly pathogenic avian influenza (HPAI) virus involved in an outbreak causing death in free-ranging wild birds at Mysore, Karnataka state of India. The virus was typed as HPAI A(H5N8) by conventional and TaqMan probe based real-time PCR assays. Six isolates of HPAI virus were recovered in 9-day-old embryonated chicken eggs. Haemagglutinin gene-based phylogeny of virus isolates showed >?99.9% nucleotide sequence identity with HPAI A(H5N8) isolates from migratory birds and domestic poultry from China and Korea indicating either these wild birds have routed their migration through Korea and/or eastern China or these dead birds must have directly or indirectly contacted with wild birds migrating from Eastern China and/or Korean regions. The study emphasises the role of migratory wild birds in spread of HPAI across the globe. 相似文献
5.
Bruntje Lüdtke Isabelle Moser Diego Santiago-Alarcon Markus Fischer Elisabeth KV. Kalko H. Martin Schaefer Marcela Suarez-Rubio Marco Tschapka Swen C. Renner 《PloS one》2013,8(12)
Human-induced forest modification can alter parasite-host interactions and might change the persistence of host populations. We captured individuals of two widespread European passerines (Fringilla coelebs and Sylvia atricapilla) in southwestern Germany to disentangle the associations of forest types and parasitism by haemosporidian parasites on the body condition of birds. We compared parasite prevalence and parasite intensity, fluctuating asymmetries, leukocyte numbers, and the heterophil to lymphocyte ratio (H/L-ratio) among individuals from beech, mixed-deciduous and spruce forest stands. Based on the biology of bird species, we expected to find fewer infected individuals in beech or mixed-deciduous than in spruce forest stands. We found the highest parasite prevalence and intensity in beech forests for F. coelebs. Although, we found the highest prevalence in spruce forests for S. atricapilla, the highest intensity was detected in beech forests, partially supporting our hypothesis. Other body condition or health status metrics, such as the heterophil to lymphocyte ratio (H/L-ratio), revealed only slight differences between bird populations inhabiting the three different forest types, with the highest values in spruce for F. coelebs and in mixed-deciduous forests for S. atricapilla. A comparison of parasitized versus non-parasitized individuals suggests that parasite infection increased the immune response of a bird, which was detectable as high H/L-ratio. Higher infections with blood parasites for S. atricapilla in spruce forest indicate that this forest type might be a less suitable habitat than beech and mixed-deciduous forests, whereas beech forests seem to be a suboptimal habitat regarding parasitism for F. coelebs. 相似文献
6.
Background
Most mathematical models of biochemical pathways consider either signalling events that take place within a single cell in isolation, or an 'average' cell which is considered to be representative of a cell population. Likewise, experimental measurements are often averaged over populations consisting of hundreds of thousands of cells. This approach ignores the fact that even within a genetically-homogeneous population, local conditions may influence cell signalling and result in phenotypic heterogeneity. We have developed a multi-scale computational model that accounts for emergent heterogeneity arising from the influences of intercellular signalling on individual cells within a population. Our approach was to develop an ODE model of juxtacrine EGFR-ligand activation of the MAPK intracellular pathway and to couple this to an agent-based representation of individual cells in an expanding epithelial cell culture population. This multi-scale, multi-paradigm approach has enabled us to simulate Extracellular signal-regulated kinase (Erk) activation in a population of cells and to examine the consequences of interpretation at a single cell or population-based level using virtual assays.Results
A model consisting of a single pair of interacting agents predicted very different Erk activation (phosphorylation) profiles, depending on the formation rate and stability of intercellular contacts, with the slow formation of stable contacts resulting in low but sustained activation of Erk, and transient contacts resulting in a transient Erk signal. Extension of this model to a population consisting of hundreds to thousands of interacting virtual cells revealed that the activated Erk profile measured across the entire cell population was very different and may appear to contradict individual cell findings, reflecting heterogeneity in population density across the culture. This prediction was supported by immunolabelling of an epithelial cell population grown in vitro, which confirmed heterogeneity of Erk activation.Conclusion
These results illustrate that mean experimental data obtained from analysing entire cell populations is an oversimplification, and should not be extrapolated to deduce the signal:response paradigm of individual cells. This multi-scale, multi-paradigm approach to biological simulation provides an important conceptual tool in addressing how information may be integrated over multiple scales to predict the behaviour of a biological system. 相似文献7.
Nandakumar KV Karthickeyan Duraisamy Shibu Balakrishnan Sunilkumar M Jaya Sankar S Karuna D. Sagili Srinath Satyanarayana Ajay Kumar MV Donald A. Enarson 《PloS one》2013,8(10)
Settings
Kerala State, India has reported the greatest dual burden of Tuberculosis (TB) and Diabetes Mellitus (DM). Malappuram district in Kerala has monitored and recorded DM status and its control from 2010 under Revised National Tuberculosis Control Program (RNTCP).Objectives
To assess, under programme conditions, comprehensiveness of recording DM status among TB cases and the TB treatment outcomes among DM patients (disaggregated by glycemic control) and compare with-non DM patients.Design
This retrospective record review included 3,116TB patients from April 2010 to September 2011.DM was defined as per international guidelines and TB treatment outcomes were categorized as favourable(cured and treatment completed) and unfavourable(death, default, failure and transfer out). Relative Risk (RR) and 95% confidence intervals(CI) were calculated to assess the risk of unfavourable outcomes.Results
DM status was recorded in 90% of TB cases and 667 (24%) had DM. 17% of DM patients and 23% of patients with unknown DM status had unfavourable outcomes but this difference was not statistically significant. Unadjusted RR for poor glycemic control or unknown control status for unfavourable outcome were (2.00; 95% CI 0.97–4.13) and (2.14; 95% CI 1.11–4.13).Conclusion
This study could not confirm an adverse association between DM or its control during treatment and the course of response to TB treatment.DM screening in TB cases and recording of DM care needs to be improved to enable more conclusive evidence. 相似文献8.
The objective of this work was to prepare and evaluate ketorolac tromethamine-loaded albumin microspheres using a factorial
design. Albumin microspheres were prepared by emulsion cross-linking method. Selected formulations were characterized for
their entrapment efficiency, particle size, surface morphology, and release behavior. Analysis of variance (ANOVA) for entrapment
efficiency indicated that entrapment efficiency is best fitted to a response surface linear model. From the statistical analysis
it was observed that as the drug:polymer (D∶P) ratio and volume of glutaraldehyde increased, there was a significant increase
in the encapsulation efficiency. Scanning electron microscopy of the microspheres revealed a spherical, nonporous and uniform
appearance, with a smooth surface. Based on the entrapment efficiency and physical appearance, 9 formulations were selected
for release study. The maximum particle size observed was below 40 μm. The release pattern was biphasic, characterized by
an initial burst effect followed by a slow release. All selected microspheres, except those having less polymer proportion
(D∶P ratio is 1∶1), exhibited a prolonged release for almost 24 hours. On comparingr
2 values for Higuchi and Peppas kinetic models, different batches of microspheres showed Fickian, non-Fickian, and diffusion
kinetics. The release mechanism was regulated by D∶P ratio and amount of cross-linking agent. From the experimental data obtained
with respect to particle size and extent of drug relaase, it could be concluded that the prepared microspheres are useful
for once-a-day intramuscular administration of ketorolac tromethamine.
Published: February 23, 2007 相似文献
9.
Analysis of optimal phenotypic space using elementary modes as applied to Corynebacterium glutamicum
Background
Quantification of the metabolic network of an organism offers insights into possible ways of developing mutant strain for better productivity of an extracellular metabolite. The first step in this quantification is the enumeration of stoichiometries of all reactions occurring in a metabolic network. The structural details of the network in combination with experimentally observed accumulation rates of external metabolites can yield flux distribution at steady state. One such methodology for quantification is the use of elementary modes, which are minimal set of enzymes connecting external metabolites. Here, we have used a linear objective function subject to elementary modes as constraint to determine the fluxes in the metabolic network of Corynebacterium glutamicum. The feasible phenotypic space was evaluated at various combinations of oxygen and ammonia uptake rates. 相似文献10.