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61.
Paddy rice samples were parboiled by soaking at 65 °C for 180 min and steaming at 96 °C for 2–10 min, and then dried to achieve the final moisture content of 11% ± 1%. The degree of starch gelatinization(DSG) and several quality attributes(head rice yield(HRY), color value and hardness) of parboiled rice were measured. Results showed that DSG(46.8%–77.9%), color value(18.08–19.04) and hardness(118.6–219.2 N) all increased following steaming. In contrast, the HRY increased(64.8%–67.1%) for steaming times between 2–4 min but decreased(67.1%–65.0%) for steaming times between 4–10 min. Linear relations between DSG and color value(R~2 = 0.87), and DSG and hardness(R~2 = 0.88) were observed. The suitable DSG of parboiled rice leading to the highest HRY was found to be 62.5%, obtained following 4 min of steaming.  相似文献   
62.

Background

Recently, botulinum neurotoxin (BoNT)-derived recombinant proteins have been suggested as potential botulism vaccines. Here, with concentrating on BoNT type E (BoNT/E), we studied two of these binding domain-based recombinant proteins: a multivalent chimer protein, which is composed of BoNT serotypes A, B and E binding subdomains, and a monovalent recombinant protein, which contains 93 amino acid residues from recombinant C-terminal heavy chain of BoNT/E (rBoNT/E-HCC). Both proteins have an identical region (48 aa) that contains one of the most important BoNT/E epitopes (YLTHMRD sequence).

Methods

The recombinant protein efficiency in antibody production, their structural differences, and their BoNT/E-epitope location were compared by using ELISA, circular dichroism, computational modeling, and hydrophobicity predictions.

Results

Immunological studies indicated that the antibody yield against rBoNT/E-HCC was higher than chimer protein. Cross ELISA confirmed that the antibodies against the chimer protein recognized rBoNT/E-HCC more efficiently. However, both antibody groups (anti-chimer and anti-rBoNT/E-HCC antibodies) were able to recognize other proteins. Structural studies with circular dichroism showed that chimer proteins have slightly more secondary structures than rBoNT/E-HCC.

Conclusion

The immunological results suggested that the above-mentioned identical region in rBoNT/E-HCC is more exposed. Circular dichroism, computational protein modeling and hydrophobicity predictions indicated a more exposed location for the identical region in rBoNT/E-HCC than the chimer protein, which is strongly in agreement with immunological results. Iran. Biomed. Key Words: Botulinum neurotoxin type E (BoNT/E), Cross ELISA, circular dichroism, Computational modeling, recombinant vaccine-candidates  相似文献   
63.
W Ebrahim  J Kjer  M El Amrani  V Wray  W Lin  R Ebel  D Lai  P Proksch 《Marine drugs》2012,10(5):1081-1091
Chemical investigation of the EtOAc extract of the endophytic fungus Bionectria ochroleuca, isolated from the inner leaf tissues of the plant Sonneratia caseolaris (Sonneratiaceae) from Hainan island (China), yielded two new peptides, pullularins E and F (1 and 2) together with three known compounds (3–5). The structures of the new compounds were unambiguously determined on the basis of one- and two-dimensional NMR spectroscopy as well as by high-resolution mass spectrometry. The absolute configurations of amino acids were determined by HPLC analysis of acid hydrolysates using Marfey’s method. The isolated compounds exhibited pronounced to moderate cytotoxic activity against the mouse lymphoma cells (L5178Y) with EC50 values ranging between 0.1 and 6.7 µg/mL.  相似文献   
64.
Receptor tyrosine kinases are key regulators of cellular growth and proliferation. Dysregulations of receptor tyrosine kinases in cancer cells may promote tumorigenesis by multiple mechanisms including enhanced cell survival and inhibition of cell death. Araguspongines represent a group of macrocyclic oxaquinolizidine alkaloids isolated from the marine sponge Xestospongia species. This study evaluated the anticancer activity of the known oxaquinolizidine alkaloids araguspongines A, C, K and L, and xestospongin B against breast cancer cells. Araguspongine C inhibited the proliferation of multiple breast cancer cell lines in vitro in a dose-dependent manner. Interestingly, araguspongine C-induced autophagic cell death in HER2-overexpressing BT-474 breast cancer cells was characterized by vacuole formation and upregulation of autophagy markers including LC3A/B, Atg3, Atg7, and Atg16L. Araguspongine C-induced autophagy was associated with suppression of c-Met and HER2 receptor tyrosine kinase activation. Further in-silico docking studies and cell-free Z-LYTE assays indicated the potential of direct interaction between araguspongine C and the receptor tyrosine kinases c-Met and HER2 at their kinase domains. Remarkably, araguspongine C treatment resulted in the suppression of PI3K/Akt/mTOR signaling cascade in breast cancer cells undergoing autophagy. Induction of autophagic death in BT-474 cells was also associated with decreased levels of inositol 1,4,5-trisphosphate receptor upon treatment with effective concentration of araguspongine C. In conclusion, results of this study are the first to reveal the potential of araguspongine C as an inhibitor to receptor tyrosine kinases resulting in the induction of autophagic cell death in breast cancer cells.  相似文献   
65.
66.
Background: The ovariectomized animals are good models to evaluate the effect of different steroid hormone treatments on implantation events and the pattern of integrin expression. Therefore, this study was performed to compare the expression of integrins and osteopontin (OPN) in correlation with pinopode development in ovariectomized mice endometrium which was subjected to steroid hormones. Methods: Ovariectomized mice were subjected to estrogen, progesterone and estrogen-progesterone hormones. Their uterine horns were evaluated for integrin expression by immunohistochemistry and real-time RT-PCR and for pinopode development by transmission and scanning electron microscopic studies. Results: No immunostaining for integrin and OPN molecules were detected in the endometrium of non-ovariectomized mice except in metestrus phase. The α4 and β1 integrin genes were expressed in all phases of estrous cycle. In ovariectomized mice, no reaction was detected in the endometrium of control, sham and estrogen-treated groups, but in both progesterone-treated groups, all examined genes were expressed. There was not any correlation between pinopodes and integrin expression in ovariectomized mice. Conclusion: The progesterone is more effective on endometrial integrin expression than estrogen and differences in the expression pattern of integrins reflect their important and different roles in embryo implantation. The pinopodes may have minor effect in mice implantation or have some delay in their expressions in ovariectomized mice which were subjected to exogenous hormones. Key Words: Endometrium, Estrogen, Integrin, Ovariectomized mice, Osteopontin (OPN)  相似文献   
67.
Whole genome sequencing of a copper resistant (CuR) black rot strain of Xanthomonas campestris pv. campestris (Xcc) isolated from a broccoli plant in Trinidad revealed a unique operon for copper resistance. The cop genes of strain Xcc-BrA1 were determined to be present on a 160 to 180 kb plasmid shown to be non-conjugative with other xanthomonads. While nucleotide comparison of a putative 8.0 Kbp copLABMGF gene cluster identified in Xcc-BrA1 genome did not reveal any homologous region with other known CuR Xanthomonas strains from diverse origins, the comparison of the translated amino acid sequence indicated similarity with X. citri, X. c. pv. citrumelonis and X. vesicatoria Cop proteins. Cloning of the copLAB gene cluster from Xcc-BrA1 conferred copper resistance to other copper-sensitive xanthomonads. Although Xcc-BrA1 harbors copLAB genes with similar sizes and organization and is able to grow on Cu-amended medium as other CuR xanthomonads, the phylogenetic analysis of nucleotide sequences indicates that the cop cluster in Xcc-BrA1 is unique and distantly related to other copLAB genes from Xanthomonas and Stenotrophomonas. The origin of copper resistance genes in Xcc-BrA1 is likely a result of horizontal gene acquisition from a still unknown phylloplane cohabitant. The findings of this study have implications for the management of crop diseases caused by CuR xanthomonads. Future studies could focus on and determining the distribution, overall importance and appropriate control measures for strains harbouring these unique genes.  相似文献   
68.
A 10 weeks trial was performed to investigate how different carbon sources (sugar beet molasses: SBM+BFT, sugar: S+BFT, corn starch: CS+BFT) along with control affect welfare status of common carp (Cyprinus carpio L.) fingerlings in biofloc‐based tanks. Three hundred healthy fingerlings (22.5 ± 0.2 g) were randomly distributed in 12 tanks (70 L) at a density of 8.02 kg/m3 (25 fish/tank). The fish in BFT treatments fed only 75% feeding rate of control. At the end of the experiment no differences were seen between the groups in case of growth performance, but the fish reared in CS+BFT had a significant lower food conversion ratio compared with the others (p < .05). Different carbon sources did not affect on haematological parameters (p > .05). Total serum protein and antibody concentration differed in treatments, and the highest values were found in S+BFT and CS+BFT treatments (p < .05). No significant differences were observed in case of lysozyme, superoxide dismutase and complement activity in treatments (p > .05), whereas the fish in BFT treatments showed a significant higher total antioxidant capacity and lower glutathione peroxidase than the control (p < .05). Different carbon sources resulted in no change in goblet and kupffer cells in intestine and liver respectively. The highest relative percentage survival was obtained in the CS+BFT and S+BFT (50%) in comparison with SBM+BFT (20%) treatment. The results obtained in this experiment, suggest that corn starch improves immune response, diseases resistance and histology of digestive and respiratory systems in carp fingerlings when used as a carbon source in zero water exchange system.  相似文献   
69.
Potato is a staple food crop and the most important agricultural commodity, which critically affects food security and economic stability in Hamadan Province, Iran. Ex-ante sustainability appraisal of new cropping systems and their comparisons with conventional systems can increase the efficiencies of innovations and changes within the production process. This study aimed to explore the sustainability levels of potato cropping systems in Hamadan Province, Iran. To this end, DEXi methodology was developed for the sustainability assessment of the cropping systems. For assessing the three dimensions of environmental, economic, and social sustainability in the four systems of traditional potato system (TPS), Quasi-industrial potato system (QIPS), industrial potato system (IPS), and government-promoted potato system (GPPS), five groups of features were utilized: (1) irrigation method; (2) seed placement; (3) farm machinery use; (4) agrochemical use; and (5) rotation. The impact assessments of the cropping systems were based on two, three, and two groups of ecological, social, and economic indicators, respectively. Employment, supply chain, protection, operational difficulty, productivity, profitability, input use, and biodiversity resulted in 21 basic indicators and 13 aggregated indicators, by which the cropping systems were described. The results revealed that GPPS with distinctive economic and social profiles could have a better overall sustainability despite the fact that some indicators like biodiversity could be negatively affected. Finally, three strategies were recommended for the sustainability of GPPS as follows: biodiversity enhancement, input substitution, and integrated water management.  相似文献   
70.
We investigated the effects of soybean phosphatidylcholine (PtCho) on the growth, fatty acid (FA) profile, and body composition of juvenile Caspian brown trout. Juvenile trout, initial average weight 0.8 ± 0.12 g, were fed semi-purified formulated diets supplemented with 2, 4, and 6% PtCho for 5 weeks. Results showed that fish with diets containing 4 or 6% PtCho had significantly greater growth. The FA profiles of both the polar lipids (PL) and neutral lipids (NL) in juvenile tissues were influenced by dietary FA, although the effects of PtCho supplementation were more marked for PL than for NL. Fish fed PtCho in the diet also had higher levels of 18:2n-6, 20:4n-6 and n-6, and significantly lower levels of docosahexaenoic acid and eicosapentaenoic acid in both PL and NL. The lipid contents of whole-body tissues and liver were positively affected by PtCho percentage in the diet. Specific growth rate, hepatosomatic index, visceralsomatic index, and protein efficiency ratio were also significantly influenced by dietary PtCho. The results of our study indicate that dietary PtCho has a growth-promoting effect and that juvenile Caspian brown trout have a relatively moderate PtCho requirement (at least 4% dry weight of the diet).  相似文献   
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