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991.
992.
Bacterial Diversity Dynamics Associated with Different Diets and Different Primer Pairs in the Rumen of Kankrej Cattle 总被引:1,自引:0,他引:1
Dipti W. Pitta Nidhi Parmar Amrut K. Patel Nagaraju Indugu Sanjay Kumar Karsanbhai B. Prajapathi Anand B. Patel Bhaskar Reddy Chaitanya Joshi 《PloS one》2014,9(11)
The ruminal microbiome in herbivores plays a dominant role in the digestion of lignocellulose and has potential to improve animal productivity. Kankrej cattle, a popular native breed of the Indian subcontinent, were used to investigate the effect of different dietary treatments on the bacterial diversity in ruminal fractions using different primer pairs. Two groups of four cows were assigned to two primary diets of either dry or green forages. Each group was fed one of three dietary treatments for six weeks each. Dietary treatments were; K1 (50% dry/green roughage: 50% concentrate), K2 (75% dry/green roughage: 25% concentrate) and K3 (100% dry/green roughage). Rumen samples were collected using stomach tube at the end of each dietary period and separated into solid and liquid fractions. The DNA was extracted and amplified for V1–V3, V4–V5 and V6–V8 hypervariable regions using P1, P2 and P3 primer pairs, sequenced on a 454 Roche platform and analyzed using QIIME. Community compositions and the abundance of most bacterial lineages were driven by interactions between primer pair, dietary treatment and fraction. The most abundant bacterial phyla identified were Bacteroidetes and Firmicutes however, the abundance of these phyla varied between different primer pairs; in each primer pair the abundance was dependent on the dietary treatment and fraction. The abundance of Bacteroidetes in cattle receiving K1 treatment indicate their diverse functional capabilities in the digestion of both carbohydrate and protein while the predominance of Firmicutes in the K2 and K3 treatments signifies their metabolic role in fibre digestion. It is apparent that both liquid and solid fractions had distinct bacterial community patterns (P<0.001) congruent to changes in the dietary treatments. It can be concluded that the P1 primer pair flanking the V1–V3 hyper-variable region provided greater species richness and diversity of bacterial populations in the rumen of Kankrej cattle. 相似文献
993.
N. V. Joshi 《Journal of genetics》2000,79(1):9-15
The very insightful Trivers-Willard hypothesis, proposed in the early 1970s, states that females in good physiological condition
are more likely to produce male offspring when the variance of reproductive success among males is high. The hypothesis has
inspired a number of studies over the last three decades aimed at its experimental verification, and many of them have found
adequate supportive evidence in its favour. Theoretical investigations, on the other hand, have been few, perhaps because
formulating a population-genetic model for describing the Trivers-Willard hypothesis turns out to be surprisingly complex.
The present study is aimed at using a minimal population-genetic model to explore one specific scenario, namely how is the
preference for a male offspring by females in good condition altered wheng, the proportion of such females in the population, changes from a low to a high value. As expected, when the proportion of
such females in good condition is low in the population, i.e. for low values ofg, the Trivers-Willard (TW) strategy goes to fixation against the equal investment strategy. This holds true up to gmax, a critical value ofg, above which the two strategies coexist, but the proportion of the TW strategy steadily decreases asg increases to unity. Similarly, when the effect of well-endowed males attaining disproportionately high number of matings
is more pronounced, the TW strategy is more likely to go to fixation. Interestingly, the success of the TW strategy has a
complex dependence on the variance of the physiological condition of females. If the difference in the two types of conditions
is not large, TW strategy is favoured, and its success is more likely as the difference increases. However, beyond a critical
value of the difference, the TW strategy is found to be less and less likely to succeed as the difference becomes larger.
Possible reasons for these effects are discussed.
This paper is dedicated to the memory of W. D. Hamilton. 相似文献
994.
Two specimens of Valenciennea helsdingenii (Bleeker, 1858) were collected off Punnakayal coast, from Gulf of Mannar, southeast coast of India in November 2012. The morphometric and meristic characters of the recorded specimens are described and discussed. This is the first record of the species from the Indian waters that is a range extension of its known range within the Indian Ocean. 相似文献
995.
996.
In S. richardsonii, unlike its testis, the whole of the ovary is fertile. The oogonia pass through seven maturation stages to form the ripe ova. The residual oogonia are responsible for the development of the new crop of oogonia. The zonation of the ooplasm reveals that a majority of the oocytes have a darkly stained inner and a lightly stained outer zone. The yolk nucleus probably has some relationship with the process of vitellogenesis. The nucleoli are produced by the division and fragmentation of the nucleolus. Extrusion of nucleoli appears to be associated with the formation of yolk. The formation of yolk globules in the oocyte begins in the periphery of the ooplasm and moves inward till the whole of the ooplasm in impregnated with yolk. As the yolk vesicles are PAS-positive in this fish, they contain mucopolysaccharides. The ovarian cycle can be divided into five stages. The ovary becomes much enlarged and distended in the month of October and delicate and thin in March. The spawning season extends from late October to December and the ovary exhibits asynchronism. 相似文献
997.
A Joshi H Moss P Riesz 《International journal of radiation biology and related studies in physics, chemistry, and medicine》1978,34(2):165-176
The post-irradiation growth of the spin-adduct nitroxide radical produced by the addition of the thymine--OD radical to t-nitrosobutane (tNB) in gamma-irradiated, de-aerated D2O solutions was investigated by e.s.r. The thymine--OD radical was formed by the addition of an OD radical to the C(5) position of thymine. Growth reached a greater maximum value and was more rapid with increasing dose. At a fixed dose, growth was also greater and more rapid if oxygen was present after gamma-radiolysis. The addition of a second radical to the spin-adduct nitroxide during radiolysis to give a diamagnetic intermediate, which can regenerate the spin-adduct radical during storage in air-free and in air-saturated solutions at room temperature, was inferred to be responsible for post-irradiation growth. U.V. photolysis at 260-280 nm of a solution containing the diamagnetic intermediate rapidly regenerates the spin-adduct nitroxide. The longer lifetime of the diamagnetic intermediate in oxygen-free solutions may be relevant to an understanding of the anoxic sensitization by nitroxides in cellular systems. 相似文献
998.
999.
Alfredi A. Moyo Kishor S. Jagadhane Sneha R. Bhosale Devashree N. Patil Vinod B. Shimpale Prashant V. Anbhule 《化学与生物多样性》2023,20(8):e202300332
The present study shows the chemical profile, antimicrobial, antiproliferative, and apoptotic effects of Stemodia viscosa extracts. Thirteen bioactive compounds were identified in the 80 % ethanolic extract by GC/MS analysis. The acetone extract exhibited a higher content of flavonoids and phenols of 805.10 μg QE/mg DW and 89.31 μg GAE/mg DW extracts, respectively. Furthermore, the acetone extract possessed the highest antioxidant activity (IC50=9.96 μg/mL). The 80 % ethanolic extract exhibited significant antimicrobial activity; the highest activity was observed against Staphylococcus aureus with a zone of inhibition of 25±0.51 mm, MIC value of 4 mg/mL, and MBC value of 8 mg/mL. The antiproliferative results revealed the presence of anticancer activity with an IC50=91.562 and 74.362 μg/mL against the B16F10 skin and COLO205 colon cancer cells, respectively. The flow cytometric analysis shows that the plant extracts cause cancer cell death through the induction of apoptosis. Our findings confirmed that Stemodia viscosa is a potential source of biologically active compounds. 相似文献
1000.
Siva Kumar Rokkam Dr. Javier A. Mas-Rosario Bishnu P. Joshi Dr. Mayank Joshi Dr. Angshuman Roy Choudhury Dr. Swayamsiddha Kar Prof. Dr. Nageswara Rao Golakoti Prof. Dr. Michelle E. Farkas 《化学与生物多样性》2023,20(9):e202300822
Curcumin has antioxidant properties resulting from its radical scavenging ability and inhibition of inflammation-associated factors. However, its lack of solubility, instability, and poor bioavailability are impediments to its therapeutic use. As potential alternatives, we synthesized and performed chemical analysis of thirty diarylidene-N-methyl-4-piperidone (DANMP), diheteroarylidene-N-methyl-4-piperidone (DHANMP), and spirobibenzopyran (SBP) derivatives, one of which was also characterized by single crystal X-ray diffraction. All compounds were evaluated for antioxidant activity via 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and for drug-like properties in silico. A subset of five compounds was investigated in terms of aqueous solubilities, which were significantly improved compared to that of curcumin. In vitro assessments of cellular and anti-inflammatory effects were conducted via real time polymerase chain reaction (RT-PCR) and Griess assays to evaluate the presence of inflammatory/activated (M1) markers and production of nitric oxide (NO) species, which are associated with inflammation. The five compounds reduced levels of markers and NO to extents similar to or better than curcumin in inflamed cells, and showed no adverse effects on cell viability. We show that these compounds possess anti-inflammatory properties and may be used as curcumin-substitutes with improved characteristics. 相似文献