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961.
Finger millet (Eleusine coracana (L.) Gaertn.), an economically important food crop is cultivated widely in the arid and semi-arid tropics of Africa and Asia. In the present study, an efficient micropropagation protocol has been established for finger millet genotypes CO 9, CO (Ra) 14 and GPU 28 using shoot apical meristems (SAMs). Shoot proliferation medium (SPM) containing Murashige and Skoog’s (MS) medium amended with 3.0 mg/l 6-benzylaminopurine produced the highest shoot regeneration frequency (86.60%) with an average of 26.45?±?0.34 shoots per explant and 6.26?±?0.38 cm shoot length in CO 9. An increase in the number of shoots per explant was observed when SAMs were repeatedly sub-cultured in SPM at 2 weeks interval for 8 weeks. Rooting of the regenerated shoots was achieved in full-strength MS medium containing indole-3-acetic acid (IAA) or indole-3-butyric acid. Rooting medium containing 0.25 mg/l IAA exhibited highest rooting frequency (100%) with an average root length of 4.44?±?0.15 cm. In vitro rooted shoots transferred to the field conditions resulted in 100% survivability.Genetic fidelity of 3-month old mother plant and micropropagated plantlets was confirmed using 3′-anchored dinucleotide inter simple sequence repeats. A total of 115 amplicons generated for CO 9, CO (Ra) 14 and GPU 28 were monomorphic, revealing no variation among mother plant and micropropagated plantlets. Thus, SAMs could serve as a suitable explant for the mass multiplication of true-to-type plants and genetic transformation in finger millet. 相似文献
962.
Prem Kumar Viji Babu Carmela Rianna Gazanfer Belge Ursula Mirastschijski Manfred Radmacher 《Journal of molecular recognition : JMR》2018,31(9)
Mechanical properties of myofibroblasts play a key role in Dupuytren's disease. Here, we used atomic force microscopy to measure the viscoelastic properties of 3 different types of human primary fibroblasts derived from a same patient: normal and scar dermal fibroblasts and palmar fascial fibroblasts from Dupuytren's nodules. Different stiffness hydrogels (soft ~1 kPa and stiff ~ 50 kPa) were used as cell culture matrix to mimic the mechanical properties of the natural tissues, and atomic force microscopy step response force curves were used to discriminate between elastic and viscous properties of cells. Since transforming growth factor‐β1 (TGF‐β1) is known to induce expression of α–smooth muscle actin positive stress fibers in myofibroblasts, we investigated the behavior of these fibroblasts before and after applying TGF‐β1. Finally, we performed an in vitro cell motility test, the wound healing or scratch assay, to evaluate the migratory properties of these fibroblasts. We found that (1) Dupuytren's fibroblasts are stiffer than normal and scar fibroblasts, the elastic modulus E ranging from 4.4, 2.1, to 1.8 kPa, for Dupuytren's, normal and scar fibroblasts, respectively; (2) TGF‐β1 enhances the level of α–smooth muscle actin expression and thus cell stiffness in Dupuytren's fibroblasts (E, ~6.2 kPa); (3) matrix stiffness influences cell mechanical properties most prominently in Dupuytren's fibroblasts; and (4) Dupuytren's fibroblasts migrate slower than the other fibroblasts by a factor of 3. Taking together, our results showed that mechanical and migratory properties of fibroblasts might help to discriminate between different pathological conditions, helping to identify and recognize specific cell phenotypes. 相似文献
963.
P.V. Sri Ramya Lalita Guntuku Srinivas Angapelly Shailaja Karri Chander Singh Digwal Bathini Nagendra Babu V.G.M. Naidu Ahmed Kamal 《Bioorganic & medicinal chemistry letters》2018,28(5):892-898
Synthesis of twenty new curcumin inspired 2-chloro/phenoxy quinoline derivatives is outlined in this study. The obtained new chemical entities were screened in vitro for their cytotoxic activity towards various tumor cell lines. Of the compounds screened, 6c and 9d exhibited significant activity and the most active analogue 6c displayed promising cytotoxicity against PC-3 (IC50 of 3.12?±?0.11?μM), DU-145, NCI-H460 and 4?T1 cell lines. Further, 6c and 9d have 2.1 and 1.4 times more aqueous solubility, respectively, than curcumin. Additionally, the promising candidate 6c could induce G2/M cell cycle arrest and apoptosis in PC-3 cells, as determined by AO-EB staining, DAPI staining, analysis of ROS levels as well as annexin binding assay. 相似文献
964.
Hem Bahadur Katuwal Narendra Man Babu Pradhan Jyotendra Jyu Thakuri Krishna Prasad Bhusal Prakash Chandra Aryal Ishana Thapa 《Proceedings of the Zoological Society》2018,71(2):103-113
Kathmandu Valley, Nepal is undergoing rapid urbanization but its effects on the bird communities have not been reported till date. Kathmandu Valley was categorized into urban, sub-urban and rural to study the impact of urbanization in bird communities. By mobilizing volunteers, we monitored 24 transects each with one km long in summer and winter seasons of 2016. A total of 13,749 individuals of birds belonging to 102 species were recorded. Species richness and diversity of all birds declined from rural to urban areas and showed significant variation along urban–rural gradients. Insectivore was the most species-rich guild while nectarivore the least. The richness of insectivore, frugivore and carnivore guilds showed significant variations along the urban–rural gradients and higher preference towards the rural areas. Similarly, species richness of all birds and richness of insectivore and carnivore guilds showed significant seasonal variation and were higher in the winter season. Our results indicate that richness, diversity and feeding guilds of birds show different response towards the urbanization gradients and seasons. Sub-urban areas can function as bird refugia, however, habitat enrichments (like increasing green spaces, setting up new parks and gardens, plantation of native fruiting trees etc.) are utmost necessary to support the bird communities in urban areas of Kathmandu Valley. 相似文献
965.
Effect of acidosis on Ca2+ sensitivity of skinned cardiac muscle with troponin C exchange. Implications for myocardial ischemia 总被引:1,自引:0,他引:1
By using a novel approach for the study of the effects of pH variation in skinned myocardium, the present experiments were aimed to provide new insights into the mechanism of ischemia. Ca2+ sensitivity is decreased by acid pH, but the effect is more than double in cardiac myofilaments than that in fast-twitch skeletal muscle fibers. With the technique of troponin C exchange in myocytes, we find here that the effect of pH is the same with cardiac or skeletal troponin C. These results rule out a direct H+-Ca2+ competition on the Ca2+-binding sites of troponin C as a significant mechanism of ischemia. The findings provide conclusive evidence in favor of the idea that acidosis modulates the protein-protein interactions in the regulatory complex in cardiac muscle. 相似文献
966.
The morphological and histological characteristics of the foregut of the crab Portunus sanguinolentus (Herbst) are described, with special reference to the lining and glands of the oesophagus. The oesophagus is lined throughout with an outer keratin and an inner collagen layer. Glands secreting mucopolysaccharides are to be found embedded in the connective tissue of the oesophagus. Details of the armature of the pyloric stomach are given. 相似文献
967.
W. L. BROWN JR. 《Biological journal of the Linnean Society. Linnean Society of London》1987,31(4):383-404
The four original stipulations of the definition of punctuated equilibrium (PE; Eldredge & Gould, 1972) are shown to be unsupported, and even contradicted, by the two evidential examples these authors supplied: the trilobite Phacops rana of the Middle Devonian, and the land snail Poecilozonites bermudensis of Late Pleistocene Bermuda.
The additional, much-discussed example of Bellamya unicolor and the accompanying suite of molluscan species of Pliocene-Recent African Lake Turkana, studied by Williamson, also fails to exemplify PE. In particular, the data produced for these cases appear to represent counterexamples to Mayr's paradigm of peripatric speciation , embraced by Eldredge and Gould as the central effective mechanism of PE. The data actually illustrate instead a prevailingly centrifugal pattern of speciation that will accommodate and explain episodic aspects of microevolution in a more realistic way. 相似文献
The additional, much-discussed example of Bellamya unicolor and the accompanying suite of molluscan species of Pliocene-Recent African Lake Turkana, studied by Williamson, also fails to exemplify PE. In particular, the data produced for these cases appear to represent counterexamples to Mayr's paradigm of peripatric speciation , embraced by Eldredge and Gould as the central effective mechanism of PE. The data actually illustrate instead a prevailingly centrifugal pattern of speciation that will accommodate and explain episodic aspects of microevolution in a more realistic way. 相似文献
968.
The heterochromatin in Indian muntjac (Muntiacus muntjak) is located at the periphery of primary constrictions of all the chromosomes. The X chromosome contains significantly larger amounts of heterochromatin than the rest of the complement by C-banding technique. However, the small portion of C-band region was found to be resistant by restriction endonuclease HaeIII (5'...GG decreases CC...3') and was clearly visible on the nucleus. Therefore, the position of this large heterochromatic segment is examined at somatic metaphases. The distribution of the heterochromatin of the X chromosome observed in Indian muntjac is contrary to the general pattern observed in other species, i.e., the chromosomes consisting greater amount of heterochromatin are located more peripherally than those with lesser amount. However, the smaller Y chromosome (Y1) is frequently found at the periphery. The present findings suggest that the role of heterochromatin organization in the nucleus vary between different heterochromatic segments of the same species and vary from species to species. 相似文献
969.
TOLLEY-HENRY LESLIE; RAPER C. DAVID JR.; GRANATO TOM C. 《Journal of experimental botany》1988,39(5):613-622
Net uptake of by non-nodulated soybean plants [Glycine max (L.) Merr.cv. Ransom] growing in flowing hydroponiccultures containing 05, 1.0 and 10-0 mol m3 was measured daily during a 24-d period of vegetativedevelopment to determine if amplitude of maximum and minimumrates of net uptake are responsive to external concentrations of . Removal of from the replenished solutions during each 24-h period was determinedby ion chromatography. Neither dry matter accumulation nor theperiodicity of oscillations in net uptakerate was altered bythe external concentrations. The maxima of the oscillations in net uptake rate, however, increased nearly3-fold in response to external concentrations. The maxima and minima, respectively, changed from 4.0 and 06mmol per gram root dry weight per day at an external solution level of 05 mol m3 to 152and -27 mmol per gram root dry weight per day at an external solution level of 100mol m3 . The negative values for minimum net uptake rate from100 mol m3 solutions show that net efflux was occurring andindicate thatthe magnitude of the efflux component of net uptake was responsiveto external concentration of . Key words: Nitrate uptake rate, carbon-nitrogen partitioning, flowing solution culture 相似文献
970.
Microfibrillar structure, cortical microtubule orientation andthe effect of amiprophos-methyl (APM) on the arrangement ofthe most recently deposited cellulose microfibrils were investigatedin the marine filamentous green alga, Chamaedoris orientalis.The thallus cells of Chamaedoris showed typical tip growth.The orientation of microfibrils in the thick cell wall showedorderly change in longitudinal, transverse and oblique directionsin a polar dependent manner. Microtubules run parallel to thelongitudinally arranged microfibrils in the innermost layerof the wall but they are never parallel to either transverseor obliquely arranged microfibrils. The ordered change in microfibrilorientation is altered by the disruption of the microtubuleswith APM. The walls, deposited in the absence of the microtubules,showed typical helicoidal pattern. However, the original crossedpolylamellate pattern was restored by the removal of APM. Thissuggests that cortical microtubules in this alga do not controlthe direction of microfibril orientation but control the orderedchange of microfibril orientation. Amiprophos-methyl, Chamaedoris orientalis, coenocytic green alga, cortical microtubule, microfibrillar structure, tip growth 相似文献