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51.
S. K. Sahoo S. S. Giri S. Chandra A. K. Sahu 《Zeitschrift fur angewandte Ichthyologie》2010,26(4):609-611
The aim of the experiment was to evaluate the growth and survival of Horabagrus brachysoma larvae at different stocking densities (3, 7, 13, 20, 27 and 33 larvae L?1) during their hatchery phase. Total length and wet weight of the larvae consistently decreased (P < 0.05) at the end of 14 and 28 days of rearing as the density increased. The specific growth rate was significantly (P < 0.05) highest at three larvae L?1 compared to the other five densities. The percent weight gain and survival of larvae was also highest at lowest density. The observation corroborates that catfish larvae can be reared at low densities in stagnant water conditions. Considering the value of larval growth, survival and overall weight gain, the stocking density of seven larvae L?1 has been identified as the maximum for larval rearing of H. brachysoma under hatchery conditions. 相似文献
52.
53.
Soma Roy Kiranmayee Rao Ch. Bhuvaneswari Archana Giri Lakshmi Narasu Mangamoori 《World journal of microbiology & biotechnology》2010,26(1):85-91
The present study describes the phytochemical profile and antimicrobial activity of Andrographis paniculata. For the present investigation, two samples of A. paniculata extracts, obtained by extraction in chloroform and chloroform + HCl, respectively, were compared for their antimicrobial
activity and further subjected to GC-MS analysis to find out the nature of the compounds responsible for the antimicrobial
activity. The antibacterial activities were assessed by measuring the diameter of the inhibition zones, MIC and MBC values.
Compared to the chloroform + HCl extract, the chloroform extract showed better antimicrobial activity against all the nine
pathogenic bacterial strains tested. The chloroform extract was observed to be active against the opportunistic and pathogenic
gram-negative bacteria, indicating its potential application related to noscomial infections. GC-MS results revealed phenols,
aromatic carboxylic acids and esters in the chloroform extract to be the molecules responsible for the antimicrobial activity
of A. paniculata. This is the first report on analysis of antimicrobial components from A. paniculata, and our results confer the utility of this plant extract in developing a novel broad spectrum antimicrobial agent. 相似文献
54.
Danilo E Xavier Renata C Picão Raquel Girardello Lorena CC Fehlberg Ana C Gales 《BMC microbiology》2010,10(1):217
Background
Multi-drug efflux pumps have been increasingly recognized as a major component of resistance in P. aeruginosa. We have investigated the expression level of efflux systems among clinical isolates of P. aeruginosa, regardless of their antimicrobial susceptibility profile. 相似文献55.
The role of actin cytoskeleton in oscillatory fluid flow-induced signaling in MC3T3-E1 osteoblasts 总被引:1,自引:0,他引:1
Malone AM Batra NN Shivaram G Kwon RY You L Kim CH Rodriguez J Jair K Jacobs CR 《American journal of physiology. Cell physiology》2007,292(5):C1830-C1836
Fluid flow due to loading in bone is a potent mechanical signal that may play an important role in bone adaptation to its mechanical environment. Previous in vitro studies of osteoblastic cells revealed that the upregulation of cyclooxygenase-2 (COX-2) and c-fos induced by steady fluid flow depends on a change in actin polymerization dynamics and the formation of actin stress fibers. Exposing cells to dynamic oscillatory fluid flow, the temporal flow pattern that results from normal physical activity, is also known to result in increased COX-2 expression and PGE2 release. The purpose of this study was to determine whether dynamic fluid flow results in changes in actin dynamics similar to steady flow and to determine whether alterations in actin dynamics are required for PGE2 release. We found that exposure to oscillatory fluid flow did not result in the development of F-actin stress fibers in MC3T3-E1 osteoblastic cells and that inhibition of actin polymerization with cytochalasin D did not inhibit intracellular calcium mobilization or PGE2 release. In fact, PGE2 release was increased threefold in the polymerization inhibited cells and this PGE2 release was dependent on calcium release from the endoplasmic reticulum. This was in contrast to the PGE2 release that occurs in normal cells, which is independent of calcium flux from endoplasmic reticulum stores. We suggest that this increased PGE2 release involves a different molecular mechanism perhaps involving increased deformation due to the compromised cytoskeleton. mechanotransduction; cell mechanics 相似文献
56.
Anna CC Aguiar Ananda C Cunha Isabela Penna Ceravolo Regina A Correia Gon?alves Arildo JB Oliveira Antoniana Ursine Krettli 《Memórias do Instituto Oswaldo Cruz》2015,110(7):906-913
Several species of Aspidosperma plants are used to treat diseases in
the tropics, including Aspidosperma ramiflorum, which acts against
leishmaniasis, an activity that is experimentally confirmed. The species, known as
guatambu-yellow, yellow peroba,
coffee-peroba andmatiambu, grows in the Atlantic
Forest of Brazil in the South to the Southeast regions. Through a guided
biofractionation of A. ramiflorum extracts, the plant activity
against Plasmodium falciparum was evaluated in vitro for toxicity
towards human hepatoma G2 cells, normal monkey kidney cells and nonimmortalised human
monocytes isolated from peripheral blood. Six of the seven extracts tested were
active at low doses (half-maximal drug inhibitory concentration < 3.8 µg/mL); the
aqueous extract was inactive. Overall, the plant extracts and the purified compounds
displayed low toxicity in vitro. A nonsoluble extract fraction and one purified
alkaloid isositsirikine (compound 5) displayed high selectivity indexes (SI) (= 56
and 113, respectively), whereas compounds 2 and 3 were toxic (SI < 10). The
structure, activity and low toxicity of isositsirikine in vitro are described here
for the first time in A. ramiflorum, but only the neutral and
precipitate plant fractions were tested for activity, which caused up to 53%
parasitaemia inhibition of Plasmodium berghei in mice with
blood-induced malaria. This plant species is likely to be useful in the further
development of an antimalarial drug, but its pharmacological evaluation is still
required. 相似文献
57.
CH Balachiranjeevi Naik S. Bhaskar V. Abhilash S. Akanksha B. C. Viraktamath M. S. Madhav A. S. Hariprasad G. S. Laha M. S. Prasad S. M. Balachandran C. N. Neeraja M. Satendra Kumar P. Senguttuvel K. B. Kemparaju V. P. Bhadana T. Ram G. Harika H. K. Mahadeva Swamy S. K. Hajira A. Yugander K. Pranathi M. Anila G. Rekha M. B. V. N. Kousik T. Dilip Kumar R. K. Swapnil Archana Giri R. M. Sundaram 《Molecular breeding : new strategies in plant improvement》2015,35(7):1-12
58.
Zaware P Shah SR Pingali H Makadia P Thube B Pola S Patel D Priyadarshini P Suthar D Shah M Jamili J Sairam KV Giri S Patel L Patel H Sudani H Patel H Jain M Patel P Bahekar R 《Bioorganic & medicinal chemistry letters》2011,21(2):628-632
A novel series of oxime containing benzyl-1,3-dioxane-r-2-carboxylic acid derivatives (6a-k) were designed as selective PPARα agonists, through bioisosteric modification in the lipophilic tail region of PPARα/γ dual agonist. Some of the test compounds (6a, 6b, 6c and 6f) showed high selectivity towards PPARα over PPARγ in vitro. Further, highly potent and selective PPARα agonist 6c exhibited significant antihyperglycemic and antihyperlipidemic activity in vivo, along with its improved pharmacokinetic profile. Favorable in-silico interaction of 6c with PPARα binding pocket correlate its in vitro selectivity profile toward PPARα over PPARγ. Together, these results confirm discovery of novel series of oxime based selective PPARα agonists for the safe and effective treatment of various metabolic disorders. 相似文献
59.
Dissection and cytological mapping of barley chromosome 2H in the genetic background of common wheat
We used gametocidal (Gc) chromosomes 2C and 3C(SAT) to dissect barley 2H added to common wheat. The Gc chromosome induces chromosomal breakage resulting in chromosomal aberrations in the progeny of the 2H addition line of common wheat carrying the monosomic Gc chromosome. We conducted in situ hybridization to select plants carrying structurally rearranged aberrant 2H chromosomes and characterized them by sequential C-banding and in situ hybridization. We established 66 dissection lines of common wheat carrying single aberrant 2H chromosomes. The aberrant 2H chromosomes were of either deletion or translocation or complicated structural change. Their breakpoints were distributed in the short arm (2HS), centromere (2HC) and the long arm (2HL) at a rough 2HS/2HC/2HL ratio of 2:1:2. We conducted PCR analysis of the 66 dissection lines using 115 EST markers specific to chromosome 2H. Based on the PCR result, we constructed a physical or cytological map of chromosome 2H that were divided into 34 regions separated by the breakpoints of the aberrant 2H chromosomes. Forty-seven markers were present in 2HS and 68 in 2HL. We compared the 2H cytological map with a previously reported 2H genetic map using 44 markers that were used in common to construct both maps. The order of markers in the distal region was the same on both maps but that in the proximal region was somewhat contradictory between the two maps. We found that the markers distributed rather evenly in the genetic map were actually concentrated in the distal regions of both arms as revealed by the cytological map. We also recognized an EST-marker or gene-rich region in the 2HL interstitial region slightly to the telomere. 相似文献