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61.
Y.H.?Dewir D.?Chakrabarty M.B.?Ali E.J.?Hahn K.Y.?PaekEmail author 《Plant Growth Regulation》2005,46(3):241-251
In vitro regenerated shoots of Spathiphyllum from bioreactor were hydroponically cultured for 30 days. The response of plant growth and photosynthesis to different substrates,
photosynthetic photon flux (PPF), nutrient scheduling and electrical conductivity (EC) of hydroponic solution were studied.
The best plant growth response was observed in perlite based substrates with moderate PFF (70–100μmol m−2 s−1). Highest fresh weight, dry weight, shoot length, root length, root number and photosynthetic characteristics (chlorophyll,
carotenoids and Fv/Fm) was observed in continuous immersion system. Plant growth responses, photosynthetic rate, stomatal
conductance and transpiration rate were also found to be affected by EC levels. The optimum EC of a balanced nutrient solution
was recorded as 1.2 dS m−1. Photosynthetic activity was also characterized in terms of photochemical efficiency using measurements of chlorophyll fluorescence.
Fv/Fm (it is a measure of the intrinsic or maximum efficiency of PSII i.e. the quantum efficiency if all PSII centers were
open) also decreased significantly in plants grown under higher EC level; a decrease in this parameter indicates down regulation
of photosynthesis or photoinhibition. Antioxidant defense enzymes such as catalase (CAT), ascorbate peroxidase (APX), peroxidase
(POD), glutathione reductase (GR) and monodehydroascorbate reductase (MDHAR) significantly elevated in the leaves and roots
of plantlets at higher EC levels. This increase could reflect a defense response to the cellular damage provoked by higher
EC levels in the nutrient solution. 相似文献
62.
Enantiomerically pure (S)-atenolol was prepared by using (R,R) salen Co(III) complex for the resolution of terminal epoxide. This process was carried out at room temperature in excellent enantio selectivity. The method can be applied for large-scale preparation of (S)-atenolol without any problem. 相似文献
63.
Mazumder UK Gupta M Karki SS Bhattacharya S Rathinasamy S Sivakumar T 《Bioorganic & medicinal chemistry》2005,13(20):5766-5773
A series of mononuclear Ru(II) complexes of the type [Ru(M)2(U)]2+, where M = 2,2'-bipyridine/1,10-phenanthroline and U = tpl (Ru1), 4-Cl-tpl (Ru2), 4-CH3-tpl (Ru3), 4-CH3O-tpl (Ru4), and 4-NO2-tpl (Ru5), -pai (Ru6), where tpl = thiopicolinanilide and pai = 2-phenyl-azo-imidazole, have been prepared and characterized by IR, UV-Vis, 1H NMR, 13C-NMR, FAB-Mass spectrophotometer, and elemental analysis. The complexes display metal-ligand charge transfer (MLCT) transitions in the visible region. The title complexes were subjected to in vivo anticancer activity tests against a transplantable murine tumor cell line, Ehrlich's ascitic carcinoma (EAC) and in vitro antibacterial activity against Gram positive and Gram negative microorganisms. Ru1-Ru6 were found to increase the life span of the tumor hosts by 19-52%, and decreased tumor volume and viable ascitic cell count. The results of the present study clearly demonstrated the tumor inhibitory activity of the ruthenium chelates against transplantable murine tumor cell line. The treatment with ruthenium complexes could be secondary to tumor regression or due to the action of the compounds itself. The significant antibacterial activity was observed for Ru1-Ru4 against microorganisms like Vibrio cholera 865, Staphylococcus aureus 6571, and Shigella flexneri as compared to that of standard drug chloramphenical. Ru5 showed moderate activity against S. aureus 8530. However, all the complexes fail to show significant antibacterial activity against V. cholera 14033 and Shigella sonnai. 相似文献
64.
Wu WX Coksaygan T Chakrabarty K Collins V Rose JC Nathanielsz PW 《Biology of reproduction》2005,73(2):343-350
The purposes of this study were to determine the separate and interactive functions of progesterone and estradiol in regulating the cervical prostaglandin (PG) system in pregnant sheep at 0.7 gestations. At 106-108 days of gestational age (dGA), ewes were treated with vehicle for 14 days (n = 5) or vehicle for 12 days followed by estradiol 5 mg twice a day, intramuscularly for 2 days (n = 5) or progesterone 100 mg, twice a day, intramuscularly for 14 days (n = 5) or progesterone 100 mg twice a day, intramuscularly for 10 days and then 2 days vehicle followed by estradiol 5 mg twice a day intramuscularly for 2 days (n = 5). At 121-123 dGA, cervical tissues were obtained under halothane anesthesia. Cervical RNA and protein were extracted and analyzed for prostaglandin-endoperoxide synthase 2 (COX2), two PGE(2) receptors, PTGER2 and PTGER4, and estrogen receptor alpha (ESR1) by Northern and Western blot analysis. Immunocytochemistry and in situ hybridization were applied to localize cellular distribution of COX2, PTGER2, and PTGER4 in the cervix. Data were analyzed by ANOVA. COX2 and PTGER4 mRNAs and proteins were increased (P < 0.05) in ewes treated with combined estradiol and progesterone but not in ewes treated with estradiol or progesterone alone compared with controls. ESR1 mRNA was increased in ewes treated with progesterone and estradiol plus progesterone. In contrast, PTGER2 mRNA and protein remained the same after all treatments. COX2 mRNA and protein were localized only in cervical glandular epithelial cells, whereas PTGER2 and PTGER4 were localized in both cervical glandular epithelial and smooth muscle cells. In conclusion, these data suggest that additional progesterone priming at 0.7 gestations synergizes with estradiol to induce cervical COX2, PTGER4, and ESR1 and support our hypothesis that stimulation of the cervical PG system by estradiol is optimized by sufficient progesterone priming in the pregnant sheep cervix. 相似文献
65.
Thirty-two glass jars (3 L each) in the laboratory and outdoor tanks (300 L) were used to examine the influence of common carp ( Cyprinus carpio L. ) in increasing the fertilizer value of phoshate rock in eight treatment combinations in quadruplicate. Input of water soluble hosphate was determined to quantify the effects of bioturbation, fish excrements and soil. The level of orthophosphate in water was always lowest in the control series. Introduction of common carp fry resulted in a net increase of 0.1 to 0.114 mg. L-1 of orthophosphate attributable to the effect of fish excrement. Bioturbation caused by common carp resulted in as high as a 72 to 100 % influx of phosphate from bottom soil in the presence of phosphate rock but only about 7 to 8 % in the absence of phosphate rock.
Die Bedeutung eingesetzter Karpfen (Cyprinus carpio L.) zur Steigerung des Düngerwertes von Phosphatgestein
32 Glasgefäße (3 L Volumen) wurden im Labor und 4 Behälter (300 L) im Freien aufgestellt urn den Einfluß zunehmender Düngung durch Phosphatgestein auf Karpfen ( Cyprinus carpio L. ) in 8 unterschiedlichen Applikationen mit jeweils 4 Replikaten zu testen. Der Eintrag wasserloslichen Phosphats wurde bestimmt, urn die Wirkung von Bioturbation, Fischexkrementen und Bodensubstrat zu prüfen. Die Konzentration an Orthophosphat war in den Kontrollen am niedrigsten. Das Einsetzen von Karpfen-Jungfischen erhöhte die Nertozunahme des Orrhophosphats auf 0,1 bis 0,114 mg.-1 und diese Zunahme muß den Ausscheidungen der Fische zugeschrieben werden. Die durch die Karpfen verursachte Bioturbation resultiene in einer 72 bis 100% igen Zunahme des Influx des Phosphats aus dem Bodensubstrat wenn Phosphatgestein dem Boden zugegeben wurde, wahrend dieser Wert nur 7–8%) ohne Phosphatgestein betrug. 相似文献
Zusammenfassung
Die Bedeutung eingesetzter Karpfen (Cyprinus carpio L.) zur Steigerung des Düngerwertes von Phosphatgestein
32 Glasgefäße (3 L Volumen) wurden im Labor und 4 Behälter (300 L) im Freien aufgestellt urn den Einfluß zunehmender Düngung durch Phosphatgestein auf Karpfen ( Cyprinus carpio L. ) in 8 unterschiedlichen Applikationen mit jeweils 4 Replikaten zu testen. Der Eintrag wasserloslichen Phosphats wurde bestimmt, urn die Wirkung von Bioturbation, Fischexkrementen und Bodensubstrat zu prüfen. Die Konzentration an Orthophosphat war in den Kontrollen am niedrigsten. Das Einsetzen von Karpfen-Jungfischen erhöhte die Nertozunahme des Orrhophosphats auf 0,1 bis 0,114 mg.
66.
Sen U Dasgupta J Choudhury D Datta P Chakrabarti A Chakrabarty SB Chakrabarty A Dattagupta JK 《Biochemistry》2004,43(39):12477-12488
Hemoglobin A(2) (alpha(2)delta(2)) is an important hemoglobin variant which is a minor component (2-3%) in the circulating red blood cells, and its elevated concentration in beta-thalassemia is a useful clinical diagnostic. In beta-thalassemia major, where there is beta-chain production failure, HbA(2) acts as the predominant oxygen deliverer. HbA(2) has two more important features. (1) It is more resistant to thermal denaturation than HbA, and (2) it inhibits the polymerization of deoxy sickle hemoglobin (HbS). Hemoglobin E (E26K(beta)), formed as a result of the splice site mutation on exon 1 of the beta-globin gene, is another important hemoglobin variant which is known to be unstable at high temperatures. Both heterozygous HbE (HbAE) and homozygous HbE (HbEE) are benign disorders, but when HbE combines with beta-thalassemia, it causes E/beta-thalassemia which has severe clinical consequences. In this paper, we present the crystal structures of HbA(2) and HbE at 2.20 and 1.74 A resolution, respectively, in their R2 states, which have been used here to provide the probable explanations of the thermal stability and instability of HbA(2) and HbE. Using the coordinates of R2 state HbA(2), we modeled the structure of T state HbA(2) which allowed us to address the structural basis of the antisickling property of HbA(2). Using the coordinates of the delta-chain of HbA(2) (R2 state), we also modeled the structure of hemoglobin homotetramer delta(4) that occurs in the case of rare HbH disease. From the differences in intersubunit contacts among beta(4), gamma(4), and delta(4), we formed a hypothesis regarding the possible tetramerization pathway of delta(4). The crystal structure of a ferrocyanide-bound HbA(2) at 1.88 A resolution is also presented here, which throws light on the location and the mode of binding of ferrocyanide anion with hemoglobin, predominantly using the residues involved in DPG binding. The pH dependence of ferrocyanide binding with hemoglobin has also been investigated. 相似文献
67.
P. K. Chakrabarty R. L. Chavhan A. Ghosh D. W. Gabriel 《Journal of plant biochemistry and biotechnology.》2010,19(1):99-102
Efficient protocols developed to isolate low copy plasmid DNA from Xanthomonas axonopodis pv malvacearum (Xam) and high copy recombinant plasmid DNA from Escherichia coli are described. The protocol for extraction of low copy plasmid DNA from strains of Xam yielded high concentrations of plasmid DNA and used easily available and inexpensive chemicals in simple steps. The protocol for plasmid extraction from E. coli was rapid, cost-effective and yet yielded high concentrations of plasmid DNA. The procedures are simple and can be used to process several samples at one time. The plasmid DNA extracted by two methods was sufficiently pure, free from protein and other cellular contaminants and amenable to various molecular manipulations. 相似文献
68.
Molecular phylogeny of silk producing insects based on internal transcribed spacer DNA1 总被引:1,自引:0,他引:1
Silk moths are the best studied silk secreting insects and belong to the families Bombycidae and Saturniidae. The phylogenetic relationship between eleven silk producing insects was analyzed using the complete DNA sequence of the internal transcribed spacer DNA 1 locus. The PCR amplification and sequence analysis showed variation in length ranging from 138 bp (Antheraea polyphemus) to 911 bp (Hyalopora cecropia). Microsatellite sequences were found and was be used to distinguish Saturniidae and Bombycidae members. The nucleotide sequences were aligned manually and used for construction of phylogenetic trees based on Maximum parsimony and Maximum likelihood methods. The topology in both the approaches yielded a similar tree that supports the ancestral position of the Antheraea assama. 相似文献
69.
A microbial biodegradation of monocrotophos was studied in the present investigation. The monocrotophos-degrading enzyme was purified and characterized from two soil bacterial strains. The cells were disrupted and the membrane-bound fractions were studied for purification and characterization. Solubilization of the membrane-bound fractions released nearly 80% of the bound protein. Phase separation further enriched the enzyme fraction 34-41 times. The enzyme phosphotriesterase (PTE) from both the strains was purified to more than 1000-fold with 13%-16% yield. Purified PTE from Clavibacter michiganense subsp. insidiosum SBL11 is a monomeric enzyme with a molecular mass of 43.5 kDa (pI of 7.5), while PTE from Pseudomonas aeruginosa F10B is a heterodimeric enzyme with a molecular mass of 43 and 41 kDa (pI of 7.9 and 7.35). Both purified enzymes are stable enzymes with peak activity at pH 9.0. The enzyme from strain F10B was more thermostable (half-life=7.3 h) than that from SBL11 (half-life=6.4 h at 50 degrees C), while both showed the same temperature optimum of 37 degrees C. Inhibitors like dithiothreitol and EDTA inhibited the purified enzyme, while p-chloromercuribenzoic acid and indoleacetic acid had a very little effect. 相似文献
70.
Rathinasamy S Karki SS Bhattacharya S Manikandan L Prabakaran SG Gupta M Mazumder UK 《Journal of enzyme inhibition and medicinal chemistry》2006,21(5):501-507
Bis(1,10-phenanthroline/2,2'-bipyridine) ruthenium(II)complexes containing TCP, TTZ OPBI, and BTSC ligands (where, TCP = 1-thiocarbamoyl-3,5-diphenyl-2-pyrazoline, TTZ = 2-(3,5-diphenyl-4,5-dihydropyrazol-1-yl)-4-phenylthiazole, OPBI = 2-hydroxyphenyl benzimidazole and BTSC = benzoin thiosemicarbazone) have been prepared and characterized. The spectral data suggested that the ligands were coordinated with the metal through nitrogen, sulfur and oxygen atoms. The target complexes were tested in vivo for anticancer activity against transplantable murine tumor cell line, Ehrlich's Ascitic Carcinoma (EAC). All these complexes increased the life span of the EAC-bearing mice, decreased their tumor volume and viable ascitic cell count as well as improved Hb, RBC and WBC counts. These results suggest that the Ru(II) complexes exhibit significant antitumor activity in EAC-bearing mice. It was also observed that the ruthenium complexes protected red blood cells from 2,2'-azo-bis(2-methylpropionamidine) dihydrochloride (AAPH)- induced hemolysis. The inhibitory effect was dose-dependent at a concentration of 20-120 microg/ml. 相似文献