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21.
Faruque M. Omar Farzana T. Seraj Zeba I. Sarker R.H. Khatun A.A. 《Plant Cell, Tissue and Organ Culture》1998,54(3):191-195
The green plant regeneration ability from anthers of BR-7, a high yielding indica cultivar, Binnatoa (BA), a salt tolerant
indica land race and IR-43 was tested in N6, M8, He2 and R2 media. The response was calculated on the basis of number of anthers
producing green plants. The number of green plants per responding anther was also recorded. The response of BR-7 and BA was
poor compared to the indica cultivar IR-43 in three of the media that were tested. In N6 medium, green plant regeneration
of BA and BR-7 was respectively 10-fold and 100-fold less than the japonica cultivar Taipei 309 (T-309). No anther-derived
green regenerant was obtained from another salt tolerant indica land race, Rajashail (RAJ). The N6 medium was selected to
test green plant regeneration frequency from anthers obtained from the F1 crosses of T-309 × BR-7, T-309 × BA, T-309 × RAJ
and T-309 × BR-7 AC regenerants backcrossed with BA. Our objective was to combine the salt tolerant trait of BA and the high
yield of BR-7 in a single line. The intermediate crossing step with T-309 was performed to increase the green plant regenerability
of the anthers. All F1 progeny from the crosses with T-309 showed significantly increased callus induction compared to the
indica parent although the values were lower than the midparent means. Green plant regeneration compared to their respective
indica parents either increased or decreased but never approached the level of T-309.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
22.
A. Khatun L. Laouar M. R. Davey J. B. Power B. J. Mulligan K. C. Lowe 《Plant Cell, Tissue and Organ Culture》1993,34(2):133-140
The effects have been studied of the non-ionic surfactant, Pluronic F-68, on the growth in culture of jute (Corchorus capsularis L.) cotyledons with attached petioles, cotyledon explants and transformed roots. Supplementation of culture medium with 0.001–0.5% (w/v) of either commercial grade Pluronic F-68 or a purified fraction prepared by passage through silica gel, stimulated shoot production from the petioles of C. capsularis var. D154 and C134 cotyledons. This effect was most marked in C134, because of the failure of control cotyledons to produce shoots in the absence of Pluronic. Plants regenerated from Pluronic-treated cotyledons were morphologically normal. Growth of transformed roots of C. capsularis var. D154 was stimulated in medium supplemented with commercial grade or purified Pluronic F-68, with maximum increases in both fresh and dry weights with 0.1% (w/v) of the surfactant. Roots cultured in the presence of Pluronic F-68 could be maintained without sub-culture for up to 70 days, whereas roots cultured in the absence of Pluronic required subculture every 7 days, to prevent necrosis. Transformed roots also produced callus in the presence of 0.001–1.0% (w/v) of either commercial grade or purified Pluronic. The biotechnological implications of these results are discussed in relation to the potential value of non-ionic surfactants as growth-stimulating additives to plant culture media.Abbreviations NAA
-naphthaleneacetic acid
- BA
6-benzyladenine
- IAA
indole-3-acetic acid
- MS
Murashige & Skoog (1962) 相似文献
23.
The conformational changes accompanying thermal denaturation under neutral, acidic and reducing conditions of Cajanus cajan proteinase inhibitor were investigated using near- and far-ultraviolet circular dichroism (CD) spectroscopy. The protein inhibitor shows a reversible N<-->D transition at neutral pH with a Tm approximately equal to 63 degrees C. The negative CD band intensities at 200 nm (far-UV) and near about 280 nm (near-UV) decrease as a result of thermal stress. The effect is more pronounced at low pH and in the presence of dithiothreitol. Only partial reversibility is observed under acidic conditions. Significant changes in the near- as well as far-ultraviolet CD spectrum are observed in the presence of dithiothreitol suggestive of the importance of disulfide linkages in maintaining the structure of C. cajan proteinase inhibitor. 相似文献
24.
The present study was designed to investigate whether calcium ionophore-induced activation and apoptosis are associated with the generation of hydrogen peroxide (H2O2) in rat eggs cultured in vitro. Culture of metaphase-II (M-II) arrested eggs in Ca2+/Mg2+-deficient medium did not induce egg activation, while a second polar body was observed in 20% of eggs when cultured in Ca2+/Mg2+-supplemented medium. In Ca2+/Mg2+-deficient medium, lower concentrations of calcium ionophore (0.2,0.4 and 0.8 µm) not only induced egg activation in a dose-dependent manner but also generation of intracellular H2O2 (84.40±0.50 ng/egg) when compared to control eggs (80.46±1.34 ng/egg). The higher concentration of calcium ionophore (1.6 µm) induced apoptosis and pronounced generation of intracellular H2O2 (92.43±0.93 ng/egg) in treated eggs. Conversely, cell-permeant antioxidant such as 2(3)-tert-butyl-4-hydroxyanisole (BHA) reduced intracellular H2O2 level (81.20±1.42 ng/egg) and protected against calcium ionophore-induced morphological changes characteristics of egg activation and apoptosis. These results clearly suggest that calcium ionophore-induced activation and apoptosis are associated with the generation of intracellular H2O2 in rat eggs. 相似文献
25.
Sahida Akter Israt Jahan Mst. Riniara Khatun Mohammad
Forhad Khan Laiba Arshad Md. Jakaria Md. Areeful Haque 《Bioscience reports》2021,41(1)
Merremia vitifolia (Burm.f.) Hallier f., an ethnomedicinally important plant, used in the tribal areas to treat various ailments including fever, headache, eye inflammation, rheumatism, dysentery, jaundice and urinary diseases. The present study explored the biological efficacy of the aqueous fraction of M. vitifolia leaves (AFMV) through in vitro and in vivo experimental models. The thrombolytic and anti-arthritic effects of AFMV were evaluated by using the clot lysis technique and inhibition of protein denaturation technique, respectively. The anti-nociceptive activity of AFMV was investigated in Swiss Albino mice by acetic acid-induced writhing test and formalin-induced paw licking test. The antioxidant activities of AFMV, including 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical and total reducing power, were also tested. The qualitative phytochemical assays exhibited AFMV contains secondary metabolites such as alkaloid, carbohydrate, flavonoid, tannin, triterpenoids and phenols. In addition, AFMV showed strong antioxidant effects with the highest scavenging activity (IC50 146.61 µg/mL) and reducing power was increased with a dose-dependent manner. AFMV also revealed notable clot lysis effect and substantial anti-arthritic activity at higher doses (500 µg/mL) as compared with the control. The results demonstrated a promising reduction of the number of writhing and duration of paw licking in acetic acid-induced writhing test and formalin-induced paw licking test in a dose-dependent manner, respectively. In conclusion, AFMV provides the scientific basis of its folkloric usage, suggesting it as the vital source of dietary supplement. 相似文献
26.
Ajmeri Sultana Shimu Masum Miah Mutasim Billah Sumon Karmakar Sumon Chandro Mohanto Ratna Khatun Md. Abu Reza Kazi Md. Faisal Hoque 《Saudi Journal of Biological Sciences》2021,28(3):2014-2022
Medicinal plant-derived bioactive compounds have recently gained more interest in biological research as an important source of novel drug candidates. Phyllanthus acidus (L.) is a widely distributed herbal medicinal plant naturally used in Ayurvedic medicine in Bangladesh. The present study focused on exploring the biological potential as well as the inhibitory effect of EAC cell growth with a comparative analysis between Phyllanthus acidus fruit pulp and seed. Crude methanol extract of P. acidus (MEPA) fruit pulp and seed was assessed as DPPH and NO free radical scavengers. While Brine Shrimp lethality bioassay, the standard protocol of phytochemical screening and hemagglutination assay were performed successively to determine the toxic effect on normal cells, the identification of some crucial phytochemicals, and the existence of lectin protein. EAC (Ehrlich’s Ascites Carcinoma) cell growth inhibition was determined by hemocytometer and morphological changes of EAC cells were observed by a fluorescence microscope using Swiss albino mice. The IC50 value of MEPA fruit pulp and seed was obtained as 57.159 µg/ml and 288.743 µg/ml respectively where minimal toxic effects on Brine Shrimp nauplii demonstrates that it is a good source of natural antioxidant compounds. Again, MEPA fruit pulp and seed-mediated effective agglutination of mouse blood erythrocyte strongly support the presence of lectin protein. Furthermore, MEPA fruit pulp and seed extract-treated EAC cells showed 65.71% and 28.57% growth inhibition respectively. The fluorescent microscopic examination of EAC cells treated with MEPA fruit pulp has shown more remarkable structural changes in the nucleus than that of seed. Based on the above findings, the present study reveals that MEPA fruit pulp can be considered as a novel biological candidate for the treatment of fatal diseases shortly. 相似文献
27.
EcoHealth - An increase in surface and ground-water salinity due to climate change is reported to have become a great threat to the health of coastal inhabitants in Bangladesh. However, little is... 相似文献
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29.
M. Abubakar Siddique M. Asha Khatun M. Mashiur Rahman Gias Uddin Ahmed Mohammad Moniruzzaman 《Molluscan research.》2020,40(1):36-43
ABSTRACTWe investigated the annual gametogenic phenology of the freshwater pearl mussel, Lamellidens marginalis (Lamarck, 1819), collected from a lentic habitat at Mymensingh, Bangladesh, using biometry and histology through monthly sampling from August 2015 to July 2016. After biometric measurements, thin slices of dorso-ventral sections were cut from the middle of the mussels for histology to determine sex and level of gonadal maturation. The condition index (CI) ranged from 0.64 (March) to 0.99 (January) over the study period. The CI peaked three times (January, April and July) indicating that the mussels were ripe during these months and subsequent decreases in CI indicated spawning, which was consistent with histology. Both males and females exhibited similar patterns in terms of gonadal development, maturation and spawning activity. It was confirmed that natural populations of L. marginalis spawn throughout the year with remarkable temporal variations, except during December when the surface water temperature reaches annual minima (16.5°C). Highest spawning activity of L. marginalis was noted during February–March, May and July–November. The data obtained in the present study could be useful for the conservation managers of this commercial species by allowing harvesting of better quality mussels to be timed without interrupting major spawning activity. 相似文献
30.
Linear B-cell epitopes are critically important for immunological applications, such as vaccine design, immunodiagnostic test, and antibody production, as well as disease diagnosis and therapy. The accurate identification of linear B-cell epitopes remains challenging despite several decades of research. In this work, we have developed a novel predictor, Identification of Linear B-cell Epitope (iLBE), by integrating evolutionary and sequence-based features. The successive feature vectors were optimized by a Wilcoxon-rank sum test. Then the random forest (RF) algorithm using the optimal consecutive feature vectors was applied to predict linear B-cell epitopes. We combined the RF scores by the logistic regression to enhance the prediction accuracy. iLBE yielded an area under curve score of 0.809 on the training dataset and outperformed other prediction models on a comprehensive independent dataset. iLBE is a powerful computational tool to identify the linear B-cell epitopes and would help to develop penetrating diagnostic tests. A web application with curated datasets for iLBE is freely accessible at http://kurata14.bio.kyutech.ac.jp/iLBE/. 相似文献