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221.
David D. Haines Bela Juhasz Arpad Tosaki 《Journal of cellular and molecular medicine》2013,17(8):936-957
Progressively sophisticated understanding of cellular and molecular processes that contribute to age‐related physical deterioration is being gained from ongoing research into cancer, chronic inflammatory syndromes and other serious disorders that increase with age. Particularly valuable insight has resulted from characterization of how senescent cells affect the tissues in which they form in ways that decrease an organism's overall viability. Increasingly, the underlying pathophysiology of ageing is recognized as a consequence of oxidative damage. This leads to hyperactivity of cell growth pathways, prominently including mTOR (mammalian target of rapamycin), that contribute to a build‐up in cells of toxic aggregates such as progerin (a mutant nuclear cytoskeletal protein), lipofuscin and other cellular debris, triggering formation of senescent cellular phenotypes, which interact destructively with surrounding tissue. Indeed, senescent cell ablation dramatically inhibits physical deterioration in progeroid (age‐accelerated) mice. This review explores ways in which oxidative stress creates ageing‐associated cellular damage and triggers induction of the cell death/survival programs’ apoptosis, necrosis, autophagy and ‘necroapoptophagy’. The concept of ‘necroapoptophagy’ is presented here as a strategy for varying tissue oxidative stress intensity in ways that induce differential activation of death versus survival programs, resulting in enhanced and sustained representation of healthy functional cells. These strategies are discussed in the context of specialized mesenchymal stromal cells with the potential to synergize with telocytes in stabilizing engrafted progenitor cells, thereby extending periods of healthy life. Information and concepts are summarized in a hypothetical approach to suppressing whole‐organism senescence, with methods drawn from emerging understandings of ageing, gained from Cnidarians (jellyfish, corals and anemones) that undergo a unique form of cellular regeneration, potentially conferring open‐ended lifespans. 相似文献
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223.
Md Habibullah BAHAR Mahmud AL PARVEZ Saidur RAHMAN Rejaul ISLAM 《Entomological Research》2011,41(2):46-52
Five cultivated mulberry plant varieties, BSRM‐34, BSRM‐56, BSRM‐57, BSRM‐58 and BSRM‐59, were used to evaluate the effects of plant variety on larval and cocoon characteristics of mulberry silkworm Bombyx mori L. Silkworm larvae undergo their entire larval periods on leaves of mulberry varieties. Different larval characteristics of larval weight, larval length and larval breadth were measured in different growth stages. After rearing, the fifth instar larvae were transferred into a mountage (Chandraki) structure for cocoon rearing for spinning and cocoon production. The cocoons were then harvested and different cocoon characteristics like cocoon weight, shell weight and shell percentage; and other characters like pupal weight and effective rate of rearing were measured. The results showed statistically significant differences among different varieties on larval and cocoon characteristics. The highest performance was observed by feeding the variety BSRM‐34 in respect of the average weight of 10 mature larvae (40.5 g), single mature larval length (7.6 cm) and breadth (1.0 cm), single cocoon weight (1.4 g), shell weight (0.2 g) and pupal weight (1.2 g) while the average performance was recorded by feeding varieties BSRM‐57 and BSRM‐59. The poorest performance was showed by feeding the variety BSRM‐56 (in case of larval characters) and BSRM‐58 (in case of cocoon characteristics). These two varieties also showed the poorest performance for silk yield. Through comparing all the above parameters it was concluded that BSRM‐34 is the best mulberry variety and it is recommended that Bangladeshi farmers adopt that variety for better yield of silk. 相似文献
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226.
Biofloc Technology: Emerging Microbial Biotechnology for the Improvement of Aquaculture Productivity
MAMDOH T. JAMAL MOHAMMED BROOM BANDAR A. AL-MUR MAMDOUH AL HARBI MOHAMMED GHANDOURAH AHMED AL OTAIBI MD FAZLUL HAQUE 《Polish journal of microbiology》2020,69(4):401
With the significant increases in the human population, global aquaculture has undergone a great increase during the last decade. The management of optimum conditions for fish production, which are entirely based on the physicochemical and biological qualities of water, plays a vital role in the prompt aquaculture growth. Therefore, focusing on research that highlights the understanding of water quality and breeding systems’ stability is very important. The biofloc technology (BFT) is a system that maximizes aquaculture productivity by using microbial biotechnology to increase the efficacy and utilization of fish feeds, where toxic materials such as nitrogen components are treated and converted to a useful product, like a protein for using as supplementary feeds to the fish and crustaceans. Thus, biofloc is an excellent technology used to develop the aquaculture system under limited or zero water exchange with high fish stocking density, strong aeration, and biota. This review is highlighted on biofloc composition and mechanism of system work, especially the optimization of water quality and treatment of ammonium wastes. In addition, the advantages and disadvantages of the BFT system have been explained. Finally, the importance of contemporary research on biofloc systems as a figure of microbial biotechnology has been emphasized with arguments for developing this system for better production of aquaculture with limited natural resources of water.Key words: biofloc, BFT, aquaculture, microbes, water quality, wastes 相似文献
227.
Transduction, the transfer of genetic information from one bacterial host to another by bacteriophage, has been demonstrated
inMycobacterium phlei. The ability to utilized-xylose as a sole carbon source could be transferred fromM. phlei strain SN109 (xyl
+,str-s) toM. phlei strain F89 (xyl
−,str-r) by a bacterially sterile, DNase-treated phage Bo2-lysate of donorM. phlei SN109. The marker was expressed within 15 minutes of phage infection, but the recipient bacteria had to be in early stationary
phase for transduction to occur. Controls employed in these experiments were bacteria incubated with heat-killed phage, with
phage plus antiphage serum, or with sterile broth in place of phage. Phage conversion, the appearance of a new character due
solely to phage infection, could not account for the observed phenomenon since phage Bo2, which was not previously propagated
on axyl
+ donor, failed to confer the ability to utilize xylose on axyl
− repicient.
High frequency transduction (HFT) also could be demonstrated by using phage lysates obtained fromxyl
+ transductants.
This work was presented in part at the 71st Annual Meeting of the American Society for Microbiology, Minneapolis, 2–8 May,
1971. Submitted by the senior author in partial fulfillment of the requirement for the Ph.D. degree at the Department of Microbiology,
Loyola University — Stritch School of Medicine, Maywood, Illinois. 相似文献
228.
AL. Ionescu 《Biologia Plantarum》1969,11(5):370-374
In experiments with double-hybrid maize grown in the field and in a greenhouse, we analysed the value of the suction force as related to the regime of irrigation. The results showed that the level of water supply to the plants is in good connection with the value of the suction force and the coefficient H (the relative degree of water saturation of the cells) analysed at the same time. In the case of the 2 hybrids under investigation the highest value of coefficient H was found to be between 35–48. The data indicate that the use of these two indices should take part in a physiological method for the settlement and the application of water rules in irrigation. 相似文献
229.
Cluster Computing - High-density, high-sampling rate EEG measurements generate large amounts of measurement data. When coupled with sophisticated processing methods, this presents a storage,... 相似文献
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