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221.
Spencer T. Mukai Tafazzal Hoque Fumihiro Morishita A. Saber M. Saleuddin 《Invertebrate Biology》2004,123(1):83-92
Abstract. The albumen gland is a female accessory sex gland that synthesizes and secretes perivitelline fluid around pulmonate eggs. The perivitelline fluid is composed of mainly galactogen and proteins, and is thought to provide nourishment to the embryos during development. We have previously identified the major secretory protein of the albumen gland of the freshwater snail Helisoma duryi as a native glycoprotein of ∼288 kDa, consisting of four 66-kDa subunits. In this study, the major albumen gland protein in H. duryi was purified, cloned, and the full-length cDNA sequence determined. Nucleotide sequence analysis revealed that the albumen gland protein (HdAGP) shared 83% identity with a partial cDNA sequence from a developmentally regulated albumen gland protein in Biomphalaria glabrata . The HdAGP mRNA was detected by RT-PCR in the albumen gland, ovotestis, mantle and digestive gland. SDS-PAGE analysis of the albumen gland protein in egg masses at different stages of development showed that the amount of HdAGP steadily decreased during embryogenesis, suggesting its possible catabolism by the developing embryos. Protein domain searches suggested that the HdAGP shared limited sequence identity, and adopted a similar three-dimensional conformation to the bactericidal, permeability increasing, protein family, raising the possibility of a potential bactericidal function for this important reproductive/developmental protein. 相似文献
222.
Eight methods were evaluated for assessment of the likely soil S-supply to a crop and in particular to identify likely deficiencies
in this supply. Of the methods, only sulphate production from incubated soil amended both with a S-containing amino acid and
elemental S correlated with field response of grass yield to S-fertilizer applications. Tissue S-concentrations in plants
grown for a short-term bioassay also correlated with field S-fertilizer response. Neither sulphate extracted by 3 different
salt extractions, nor sulphate production from unamended incubated soil, nor soil arylsulphatase activity, correlated with
field fertilizer response. 相似文献
223.
Nazim Uddin Emon Md Munsur Alam Md Solaman Uddin Sawon Ezazul Hoque Rana Marufa Afroj Mohammad Mehedi Hasan Tanvir 《Biochemistry and Biophysics Reports》2021
Caesalpinia digyna (Rottl.) (Family: Fabaceae) is an essential medicinal plant for it's conventional uses against a kind of human disorders. This research aims to investigate the antidiarrheal, antibacterial and antifungal properties of the methanol extract of the stems extracts of the C. digyna (MECD). The in vivo antidiarrheal activity of the stem extracts were evaluated by using castor oil-induced diarrhea, castor oil-induced enteropooling and charcoal induced intestinal transit in mice model. Besides, in vitro antimicrobial potentiality of MECD was investigated by the disc diffusion method. In silico activity of the isolated compounds were performed by Schrödinger-Maestro (Version 11.1) software. In addition, The ADME/T analysis and PASS prediction were implemented by using pass online tools. In the antidiarrheal investigation, the MECD exhibited a notable inhibition rate in all test approaches which were statistically significant (p < 0.05, p < 0.1, p < 0.01). MECD 400 mg/kg showed the maximum antidiarrheal potency in all the test methods. In vitro antimicrobial analysis unveiled that, MECD revealed higher potentiality against almost all pathogens and indicates dose-dependent activity against almost all the bacteria and fungi. In the case of in silico evaluation of anti-diarrheal, anti-bacterial and anti-fungal activity, all three isolated compounds met the pre-conditions of Lipinski's five rules for drug discovery. Pass predicted study also employed for all compounds. However, The chemical constituents of the C. digyna can be a potent source of anti-diarrheal, anti-bacterial and anti-fungal medicine and further modification and simulation studies are required to establish the effectiveness of bioactive compounds. 相似文献
224.
Md. Aminul Hoque Atefeh Taherian Fard Mosfequr Rahman Omar Alattas Kohei Akazawa Amir Feisal Merican 《Biologia》2011,66(6):954-966
We conducted an integrated study of cell growth parameters, product formation, and the dynamics of intracellular metabolite
concentrations using Escherichia coli with genes knocked out in the glycolytic and oxidative pentose phosphate pathway (PPP) for glucose catabolism. We investigated
the same characteristics in the wild-type strain, using acetate or pyruvate as the sole carbon source. Dramatic effects on
growth parameters and extracellular and intracellular metabolite concentrations were observed after blocking either glycolytic
breakdown of glucose by inactivation of phosphoglucose isomerase (disruption of pgi gene) or pentose phosphate breakdown of glucose by inactivation of glucose-6-phosphate dehydrogenase (disruption of zwf gene). Reducing power (NADPH) was mainly produced through PPP when the pgi gene was knocked out, while NADPH was produced through the tricarboxylic acid (TCA) cycle by isocitrate dehydrogenase or
NADP-linked malic enzyme when the zwf gene was knocked out. As expected, when the pgi gene was knocked out, intracellular concentrations of PPP metabolites were
high and glycolytic and concentrations of TCA cycle pathway metabolites were low. In the zwf gene knockout, concentrations of PPP metabolites were low and concentrations of intracellular glycolytic and TCA cycle metabolites
were high. 相似文献
225.
Plasmonics - A broadband nanostructure metamaterial absorber (MA) based on tri-layer metallic-optical-thin film molded shape is proposed for visible spectrum solar energy scavenging. This MA is... 相似文献
226.
Guillaume P. Gruere Imdadul Hoque Rowena Valmonte-Santos Mark W. Rosegrant 《Plant Cell, Tissue and Organ Culture》2006,86(3):411-415
This note summarizes the results of a consultation of scientific and regulatory experts in July 2005 on the potential of transgenic crops in Bangladesh. We find that Bangladeshi experts are optimistic on the potential of agricultural biotechnology to respond to biotic and abiotic stresses in their country in the future. Public research is constrained by human capacities, infrastructure and capital investment, and transgenic crop development will require the active involvement of outside partners, such as international organizations or collaboration with private companies. We also find that social acceptance of genetic engineering is not considered a major issue, but could become one, and prompted experts to call for a wider awareness campaign on the technology.This research project was conducted as part of the South Asia Biosafety Program (SABP), a project funded by the US Agency for International Development (USAID) and jointly managed by the International Food Policy Research Institute and AGBIOS Canada. The authors would like to thank the Bangladesh Agricultural
Research Council and all the participants to the
meetings in Dhaka and Mymensingh for their help. 相似文献
227.
In many longitudinal studies, the number and timing of measurements differ across study subjects. Statistical analysis of such data requires accounting for both the unbalanced study design and the unequal spacing of repeated measurements. This paper proposes a time-heterogeneous D-vine copula model that allows for time adjustment in the dependence structure of unequally spaced and potentially unbalanced longitudinal data. The proposed approach not only offers flexibility over its time-homogeneous counterparts but also allows for parsimonious model specifications at the tree or vine level for a given D-vine structure. It further provides a robust strategy to specify the joint distribution of non-Gaussian longitudinal data. The performance of the time-heterogeneous D-vine copula models are evaluated through simulation studies and by a real data application. Our findings suggest improved predictive performance of the proposed approach over the linear mixed-effects model and time-homogeneous D-vine copula model. 相似文献
228.
Christopher G. Langendorf Matthew T. O'Brien Kevin R. W. Ngoei Luke M. McAloon Urmi Dhagat Ashfaqul Hoque Naomi X. Y. Ling Toby A. Dite Sandra Galic Kim Loh Michael W. Parker Jonathan S. Oakhill Bruce E. Kemp John W. Scott 《The Journal of biological chemistry》2020,295(48):16239
The calcium-calmodulin–dependent protein kinase kinase-2 (CaMKK2) is a key regulator of cellular and whole-body energy metabolism. It is known to be activated by increases in intracellular Ca2+, but the mechanisms by which it is inactivated are less clear. CaMKK2 inhibition protects against prostate cancer, hepatocellular carcinoma, and metabolic derangements induced by a high-fat diet; therefore, elucidating the intracellular mechanisms that inactivate CaMKK2 has important therapeutic implications. Here we show that stimulation of cAMP-dependent protein kinase A (PKA) signaling in cells inactivates CaMKK2 by phosphorylation of three conserved serine residues. PKA-dependent phosphorylation of Ser495 directly impairs calcium-calmodulin activation, whereas phosphorylation of Ser100 and Ser511 mediate recruitment of 14-3-3 adaptor proteins that hold CaMKK2 in the inactivated state by preventing dephosphorylation of phospho-Ser495. We also report the crystal structure of 14-3-3ζ bound to a synthetic diphosphorylated peptide that reveals how the canonical (Ser511) and noncanonical (Ser100) 14-3-3 consensus sites on CaMKK2 cooperate to bind 14-3-3 proteins. Our findings provide detailed molecular insights into how cAMP-PKA signaling inactivates CaMKK2 and reveals a pathway to inhibit CaMKK2 with potential for treating human diseases. 相似文献
229.
5-Aminolevulinic acid (ALA), a precursor of porphyrin synthesis, increased the production of various porphyrin compounds in Candida guilliermondii cells. Metalloporphyrins and protoporphyrin IX (PPIX) were predominantly accumulated, respectively, at ALA concentrations of 0.2-0.4 mM and at those higher than 1.5 mM. 2,2;-Dipyridyl which complexed with bivalent metals significantly increased the content of endogenous PPIX even at ALA concentrations lower than 0.5 mM. Under these conditions, the yeast sensitivity to photodynamic effect of visible light (400-600 nm) dramatically increased due to photosensitization by endogenous PPIX. 相似文献
230.