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K. M. Bhaskara Reddy Dokka Mallikarjunasarma Kamana Bulliraju Vanjivaka Sreelatha Y. Bharathi Kumari Ramesh Dandala Kuppanna Ananda 《International journal of peptide research and therapeutics》2011,17(2):113-121
Abstract
An efficient stepwise synthesis of homo-oligomers and mixed oligomers of gabapentin and pregabalin on solid support using Fmoc-protected derivatives and HBTU/HOBt/DIEA as coupling agent is described. The synthesis was also carried out using solution phase methodology. The Gpn/Pgn homo oligomers and mixed oligomers forms C9 helix in solution as determined by NMR study. Chiral as well as achiral gamma amino acids were used for the synthesis of oligomers in order to investigate the secondary structural preferences. 相似文献3.
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Ananda B. Assis Catherine R. Bevier Cristine Chaves Barreto Carlos Arturo Navas 《Ecology and evolution》2020,10(2):901-913
The composition of the skin microbiota of amphibians is related to the biology of host species and environmental microbial communities. In this system, the environment serves as a microbial source and can modulate the hosted community. When habitats are fragmented and the environment disturbed, changes in the structure of this microbial community are expected. One important potential consequence of fragmentation is a compromised protective function of the microbiota against pathogenic microorganisms. In this study, the skin microbiota of the amphibian Proceratophrys boiei was characterized, evaluated for relationships with environmental variables and environmental sources of microbial communities, and its diversity evaluated for frog populations from fragmented and continuous forests. In addition, the antimicrobial activity of this skin community was studied in frogs from both forest types. Culture methods and 16S rRNA high‐throughput gene sequencing were used to characterize the microbial community and demonstrated that the skin microbiota of P. boiei is more closely related to the soil microbial communities than those inhabiting water bodies or fragment matrix, the unforested area around the forested fragment. The microbial diversity and abundance of P. boiei skin microbiota are different between continuous forests and fragments. This community is correlated with environmental variables, especially with temperature of microhabitat and distance to human dwelling. All individuals of P. boiei harbored bacteria capable of inhibiting the growth of pathogenic bacteria and different strains of the pathogenic fungus Batrachochytrium dendrobatidis, and a total of 27 bacterial genera were detected. The results of this study indicate that the persistence of populations of this species will need balanced and sustained interactions among host, microorganisms, and environment. 相似文献
5.
Gangadhar Barlaya Pinky Basumatary Raghavendra Channaveer Huchchappa Banahalli Sriramreddy Ananda Kumar Hemaprasanth Kannur 《Zeitschrift fur angewandte Ichthyologie》2021,37(5):748-758
A study was conducted with non-conventional ingredients to test their efficacy as fishmeal (FM) replacers in the diet of fringe- lipped carp. Labeo fimbriatus first feeding larvae and fry were reared for 30 and 60 days in indoor, 50 L, aerated, circular plastic tanks at 100 and 30 numbers tank−1, respectively. In the first feeding larvae to fry rearing experiment (Exp. 1), the fish were fed with either of the following isonitrogenous and isocaloric diets – live plankton, FM diet, green bottle fly (Lucilia sericata) larvae meal (GBFLM) diet and silkworm pupa (SWP) diet. The fry to fingerling rearing (Exp. 2), was also conducted using the same diets described above except live plankton. All compounded diets were formulated to contain 40% crude protein for the experiment 1 and 35% for experiment 2 and were fed ad libitum. Triplicate tanks were maintained for each treatment in both the experiments. In Exp. 1, the mean final weight of fry was higher with plankton and FM diets, while no difference (p > .05) was observed between FM and GBFLM diets. Weight of fish fed SWP diets was not statistically different from those fed GBFLM diet. No difference (p > .05) in final length, survival and condition factor was recorded. Analysis of digestive enzyme activity of whole fish revealed lower (p < .05) activity of amylase in fish fed plankton. In Exp. 2, no difference (p > .05) was observed between the different diet groups in terms of mean final weight, length, survival and condition factor. Analysis of digestive enzyme activity of whole fish revealed no difference (p > .05) in the activity of digestive enzymes between the treatments except a lower (p < .05) activity of trypsin in FM diet and lipase in FM and GBFLM diets. Since the survival and condition factors of animals is the most important aspect during nursery rearing, similar (p > .05) values recorded in different treatments indicate the possibility of incorporation of these non-conventional protein sources in the diet of L. fimbriatus during first feeding larvae to fry and fry to fingerling rearing. 相似文献
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Maia A. Rabaa Chonticha Klungthong In-Kyu Yoon Edward C. Holmes Piyawan Chinnawirotpisan Butsaya Thaisomboonsuk Anon Srikiatkhachorn Alan L. Rothman Darunee Tannitisupawong Jared Aldstadt Ananda Nisalak Mammen P. Mammen Robert V. Gibbons Timothy P. Endy Thanyalak Fansiri Thomas W. Scott Richard G. Jarman 《PLoS neglected tropical diseases》2013,7(1)
Revealing the patterns and determinants of the spread of dengue virus (DENV) at local scales is central to understanding the epidemiology and evolution of this major human pathogen. We performed a phylogenetic analysis of the envelope (E) genes of DENV-1, -2, -3, and -4 isolates (involving 97, 23, 5, and 74 newly collected sequences, respectively) sampled from school-based cohort and village-based cluster studies in Kamphaeng Phet, Thailand, between 2004 and 2007. With these data, we sought to describe the spatial and temporal patterns of DENV spread within a rural population where a future vaccine efficacy trial is planned. Our analysis revealed considerable genetic diversity within the study population, with multiple lineages within each serotype circulating for various lengths of time during the study period. These results suggest that DENV is frequently introduced into both semi-urban and rural areas in Kamphaeng Phet from other populations. In contrast, the persistence of viral lineages across sampling years was observed less frequently. Analysis of phylogenetic clustering indicated that DENV transmission was highly spatially and temporally focal, and that it occurred in homes rather than at school. Overall, the strength of temporal clustering suggests that seasonal bottlenecks in local DENV populations facilitate the invasion and establishment of viruses from outside of the study area, in turn reducing the extent of lineage persistence. 相似文献
7.
Helopeltis theivora Waterhouse (Heteroptera: Miridae), is a major sucking pest of tea in North East India along with other tea growing countries. In West Bengal, tea is cultivated in three sub-Himalayan regions, Terai (foothill plains western to river Teesta), the Dooars (foothill plains eastern to river Teesta) and the Darjeeling hill slopes. Most plantations, in these regions are managed conventionally i.e. by spraying different synthetic insecticides and a few by organic farming using different herbal and microbial insecticides. In conventional plantations, continuous application of insecticides may lead to the selection of more tolerant H. theivora populations making the pest difficult to control. So, there is a pressing need to know the biochemical variability in relation to the metabolic resistance in the pest populations and develop a population specific control strategy. Activity of three principal insecticide detoxifying enzymes in H. theivora populations were studied from three tea growing regions of North Bengal. Higher levels of activity of all the studied enzymes were found from conventional tea plantations. In male H. theivora, the activity of general esterases (GEs) was 6.6–11.2 and 10.5–11.4 fold higher, cytochrome P450 (CYPs) was 2.0–3.2 and 3.0–3.2 fold higher and glutathione S-transferase (GSTs) was 5.2–8.3 and 6.4–8.7 fold higher in Terai and the Dooars populations, respectively than organic populations from Darjeeling hill slopes. Similarly, in female H. theivora, activity of GEs was 6.2–10.3 and 8.3–9.6 folds higher, CYPs was 1.9–3.2 and 3.0–3.3 fold, and GSTs was 3.5–5.4 and 4.4–6.0 fold higher in Terai and the Dooars, respectively than the organic populations from Darjeeling hill slopes. The activities of all three enzymes were found to be significantly low in organic plantations from Darjeeling hill slopes. Esterase I–VI isozymes with higher level of expression were found in specimens from conventional tea plantations than organic populations of H. theivora from Darjeeling hill slopes in isozymes study. 相似文献
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Libraty DH Myint KS Murray CK Gibbons RV Mammen MP Endy TP Li W Vaughn DW Nisalak A Kalayanarooj S Hospenthal DR Green S Rothman AL Ennis FA 《PLoS neglected tropical diseases》2007,1(3):e111
Background
Leptospirosis is an emerging zoonosis that is often under-recognized in children and commonly confused with dengue in tropical settings. An enhanced ability to distinguish leptospirosis from dengue in children would guide clinicians and public health personnel in the appropriate use of limited healthcare resources.Methodology/Principal Findings
We conducted a prospective, hospital-based, study of children with acute febrile illnesses and dengue in Thailand. Among the children without dengue, we identified those with leptospirosis using anti-leptospira IgM and microscopic agglutination titers in paired acute and convalescent blood samples. We then performed a case-control comparison of symptoms, signs, and clinical laboratory values between children with leptospirosis and dengue.In a semi-rural region of Thailand, leptospirosis accounted for 19% of the non-dengue acute febrile illnesses among children presenting during the rainy season. None of the children with leptospirosis were correctly diagnosed at the time of hospital discharge, and one third (33%) were erroneously diagnosed as dengue or scrub typhus. A predictive model to distinguish pediatric leptospirosis from dengue was generated using three variables: the absolute neutrophil count, plasma albumin, and aspartate aminotransferase levels in the first 72 hours of illness.Conclusions/Significance
Unrecognized leptospirosis can be a significant cause of “dengue-like” febrile illness in children. Increased awareness of pediatric leptospirosis, and an enhanced ability to discriminate between leptospirosis and dengue early in illness, will help guide the appropriate use of healthcare resources in often resource-limited settings. 相似文献10.
Density functional theory (DFT) calculations and molecular dynamics (MD) simulations on the atomic level were performed on
three different substituted banana-shaped compounds derived from 1,3-phenylene bis[4-(4-n-hexyloxyphenyliminomethyl)benzoate]
(P-6-O-PIMB). The DFT studies were carried out on the isolated molecules, and in the MD simulations clusters were treated
with up to 64 monomers. The effect of polar substituents, such as chlorine and the nitro group, on the central 1,3-phenylene
unit of banana-shaped compounds was investigated. In particular, flexibility, polarity, electrostatic potential (ESP) group
charge distributions, B-factors, bending angles and molecular lengths were considered. The MD results were analysed by trajectories
of significant torsion angles as well as order parameters such as radial atom pair distribution functions g(r), orientational
correlation functions g(o), diffusion coefficients (D) and root mean square deviations (RMSD) values. The g(r) and g(o) values
show that a certain long range order is generated by the introduction of a NO2 group in the 2-position of the central 1,3-phenylene ring. In contrast, the chlorination at the 4 and 6 positions of the
central 1,3-phenylene unit decreases the long range order tendency by its perturbation effect on the conformations in such
molecules. Moreover, g(r) and g(o) values, as well as diffusion coefficients, show that in the NO2 substituted compound the formation of microphase areas is preferred. Finally, the aggregation effect in such compounds was
studied in a systematic way by a comparison of the conformational properties of the isolated molecules and the monomers in
the clusters.
Figure Molecular dynamics (MD) simulations on the aggregation behaviour of substituted banana-shaped compounds
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献