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151.
Hairtail fillets are marketed as both fresh and frozen forms in retail outlets within Japan. The present study was undertaken
to develop a rapid and reliable method for identification of the hairtail species in commercial fillets. A total of 64 fillet
samples, caught from various localities within Japan and purchased from various supermarkets, were analyzed. Polymerase chain
reaction (PCR) amplification of a portion of the mitochondrial DNA encoding 16S ribosomal RNA gene and subsequent restriction
digestion of the amplified products, using Vspl endonuclease, generated different restriction patterns indicating two different species of hairtails in the fillet samples.
The results indicated that the commercial hairtail fillets, labeled and marketed as ‘Tachiuo’ in Japan, were comprised of
two species of hairtails with Trichiurus japonicus (commonly called Tachiuo) accounting for 47% and Trichiurus sp. 2 (commonly called Tenjikutachi) accounting for 53% of the analyzed samples. This simple and inexpensive PCR-restriction
fragment length polymorphism analysis can be routinely applied to determine species composition of hairtails in commercial
fillets. 相似文献
152.
In the absence of viable alternative technology of hybrid wheat development, chemical induction of male sterility mediated technology based on chemical hybridizing agents (CHAs) holds a great potential. N-Acylaniline derivatives, namely, ethyl 4'-fluoro oxanilate (1) and ethyl 4'-trifluoromethyl oxanilate (2) containing halogen atoms in the para position of the aryl ring and substituted amide linkage (-CO-NH-) in the acyl side chain induced >98% spikelet sterility on three genotypes of wheat, namely, PBW 343, HD 2046 and HD 2733, at 1500 ppm. The active moieties were incorporated in the form of herbicide-CHA chimera and amino acid analogues using glycine and alanine as templates. The target activity was made more selective by synthesizing chimeric structure of herbicide (2,4-dichlorophenoxyacetic acid and dalapon) and the most active CHA templates, namely, 4- fluoroanilinyl and beta-ethoxycarbonyl moieties. Among herbicide-CHA chimera ethyl 2',4'-dichlorophenyl oxalate (14) induced 79.11% male sterility, whereas benzyl methyl 2-oxo-3-azaadipate (20) was the best, inducing 73.87% male sterility in HD 2733, among amino acid analogues. The CHAs were found to modify the reproductive biology to ensure cross-pollination in the cleistogamous wheat flowers, increasing the probability for the development of hybrids. 相似文献
153.
Sar TK Bagchi B Das SK Mandal TK Chakraborty AK Bhattacharyya A Choudhury A 《Journal of agricultural and food chemistry》2002,50(15):4202-4209
Toxicokinetic behavior, recovery, and metabolism studies of ACTP ester and its effect on cytochrome P(450) content of liver microsomal pellet were carried out in black Bengal goat after a single intravenous administration of 11.88 mg kg(-1) and consecutive oral administration of 79.22 mg kg(-1) for 7 days. ACTP ester achieved a maximum blood concentration of 42.64 +/- 4.26 microg mL(-1) at 0.08 h after intravenous administration followed by a sharp decline until 0.5 h, and the minimum blood concentration was recorded at 36 h (1.93 +/- 0.14 microg mL(-1)) postdosing. The kinetic behavior of ACTP ester followed a "two-compartment open model". Comparatively shorter alpha (0.81 +/- 0.02 h(-1)) and greater t1/2 (alpha) (0.86 +/- 0.03 h) indicated a slower rate of distribution of ACTP ester in goat. The t1/2(beta)()) (14.83 +/- 1.49 h) and V(d(area)) (0.91 +/- 0.19 L kg(-1)) suggested a longer elimination phase with general distribution in all compartments of the body. The higher T/B and K12/K21 values associated with a lower f(c) value suggested longer persistence in the tissue compartment at higher concentration. The higher Cl(R) compared to Cl(H) indicated the major amount was eliminated by the kidney. Maximum concentration of ACTP ester including its metabolites, triclopyr acid and trichloropyridinol, was excreted through urine at 48 h. The recovery of ACTP ester including metabolites after repeated nontoxic oral dose administration was 70.09%, of which recovery from feces was 4.45%, suggesting the major portion of administered ACTP ester was absorbed through the gastrointestinal tract of the goat. All of the tissues contained ACTP ester and its metabolites. ACTP ester did not alter the cytochrome P(450) content of the liver tissue following repeated nontoxic oral dose administration for 7 days. 相似文献
154.
S. Chakraborty 《Soil biology & biochemistry》1983,15(6):661-664
Populations of soil amoebae were estimated throughout two wheat crops and a fallow from wheat rotations suppressive and non-suppressive to take-all. The suppressive pasture-pasture-wheat plot showed higher rhizosphere populations of mycophagous amoebae and higher associations of mycophagous and other amoebae with wheat roots throughout the crop period than the non-suppressive continuous-wheat plot. Populations of mycophagous amoebae were positively and significantly (P = 0.05) correlated with populations of the take-all fungus in both soils, and with soil moisture in the non-suppressive soil. The possible role of mycophagous amoebae in the wheat rhizosphere in suppressive soil is discussed. 相似文献
155.
Lee KH Dinner AR Tu C Campi G Raychaudhuri S Varma R Sims TN Burack WR Wu H Wang J Kanagawa O Markiewicz M Allen PM Dustin ML Chakraborty AK Shaw AS 《Science (New York, N.Y.)》2003,302(5648):1218-1222
The immunological synapse is a specialized cell-cell junction between T cell and antigen-presenting cell surfaces. It is characterized by a central cluster of antigen receptors, a ring of integrin family adhesion molecules, and temporal stability over hours. The role of this specific organization in signaling for T cell activation has been controversial. We use in vitro and in silico experiments to determine that the immunological synapse acts as a type of adaptive controller that both boosts T cell receptor triggering and attenuates strong signals. 相似文献
156.
Ferguson AD Chakraborty R Smith BS Esser L van der Helm D Deisenhofer J 《Science (New York, N.Y.)》2002,295(5560):1715-1719
Siderophore-mediated acquisition systems facilitate iron uptake. We present the crystallographic structure of the integral outer membrane receptor FecA from Escherichia coli with and without ferric citrate at 2.5 and 2.0 angstrom resolution. FecA is composed of three distinct domains: the barrel, plug, and NH2-terminal extension. Binding of ferric citrate triggers a conformational change of the extracellular loops that close the external pocket of FecA. Ligand-induced allosteric transitions are propagated through the outer membrane by the plug domain, signaling the occupancy of the receptor in the periplasm. These data establish the structural basis of gating for receptors dependent on the cytoplasmic membrane protein TonB. By compiling available data for this family of receptors, we propose a mechanism for the energy-dependent transport of siderophores. 相似文献
157.
M. Parameswaran S. R. Parmar K. S. Prajapati M. K. Chakraborty 《Plant foods for human nutrition (Dordrecht, Netherlands)》1988,38(4):269-276
A tobacco leaf protein concentrate (TLPC) from bidi tobacco leaves was prepared by a heat coagulation method which contained 52% protein and was free from nicotine and polyphenols. When TLPC was fed to weanling wistar albino rats to supplement 25% of the dietary protein, the growth of the animals was found to be comparable to control animals. Reproductive performance of male and female rats fed the TLPC supplemented diet was normal and no histopathological changes were seen in their tissues. 相似文献
158.
This is a study of trace metal competition in the complexation of Pb(II) by well-characterized humic substances, namely Suwannee River Fulvic Acid (SRFA) in model solutions. It was found that Cu(II) seems to compete with Pb(II) for strong binding sites of SRFA when present at the same concentration as Pb(II). However, Cd(II) and Zn(II) did not seem to compete with Pb(II) for strong binding sites of SRFA. These two metals did compete with Pb(II) for the weaker binding sites of SRFA. Heterogeneity of SRFA was found to play a crucial role in metal–SRFA interactions. The environmental significance of this research for freshwater is that even at relatively low Pb(II) loadings, the metals associated with lead in minerals, e.g. Cu(II), may successfully compete with Pb(II) for the same binding sites of the naturally occurring organic complexants, with the result that some of the Pb(II) may exist as free Pb2+ ions, which has been reported to be one of the toxic forms of Pb in aquatic environment. 相似文献
159.
The loss of shattering of rice has long been acknowledged as a crucial step sweeping the path of domestication. Here, we collated evidence from genetics, and anthropology to challenge this long-held view. Our discussion dwelt on arguments that (1) undermined the effect of a mutation in the key locus (sh4) which does not always confer non-shattering, (2) identified the involvement of other loci, (3) uncovered natural variation in shatterability still existing in domesticated landraces, and (4) relatively recent fixation of the mutation. Similarly, cultural attributes asserted a long tradition of naturally shattering wild rice cultivation and adaptive strategies of gathering which is still widely exercised in many parts of South and South-East Asia, Africa, and Australia. Altogether, it strongly suggests that primitive agriculture thrived largely relying on wild rice or semi-domesticated shattering phenotype but non-shattering emerged into conspicuity much later in the history. 相似文献