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951.
Extraction of brown seaweed (Undaria pinnatifida) oil was carried out by using supercritical carbon dioxide (SCO2) and ethanol as co-solvent. The flow rate of ethanol was 3.0% (v/v) as compared to that of SCO2. Experiments were performed in a semi-batch flow apparatus on dried samples at temperatures from 303 to 333 K and pressures from 80 to 300 bar. Fucoxanthin and polyphenol were quantitatively analyzed by using HPLC and UV-spectrometer. The highest yields of fucoxanthin and polyphenol were shown at 200 bar, 323 K and 250 bar, 333 K, respectively. The solubility of fucoxanthin in SCO2 agreed well with the Chrastil model.  相似文献   
952.
Chromium-reducing and plant growth–promoting potential, including production of siderophores by chromium(VI)-resistant Mesorhizobium species RC1 and RC4, isolated from chickpea nodules, was assessed both in the presence and absence of chromium(VI) under in vitro conditions. The Mesorhizobium strains displayed a high level of tolerance to chromium (400 μg ml? 1), and showed a varied sensitivity to antibacterial drugs, on yeast extract mannitol (YEM) agar plates. Mesorhizobium strains RC1 and RC4 reduced chromium(VI) by 84% and 83%, respectively at pH 7 in YEM broth after 120 h of incubation. Mesorhizobial strains RC1 and RC4 produced 27 and 35 μg ml? 1 of indole acetic acid (IAA), respectively, in Luria-Bertani broth with 100 μg ml? 1 of tryptophan. The IAA production by the mesorhizobial strains did not differ significantly (p ≤ .05) under chromium stress and showed a positive reaction for siderophore, HCN, and ammonia, both in the absence and presence of chromium(VI).The present observations suggest that the chromium reducing and plant growth promoting activities of the Mesorhizobium strains could be exploited for bioremediation of chromium(VI) and to enhance the legume productivity for chromium-contaminated soils.  相似文献   
953.
A sequence alignment of yeast cytochrome-c (y-cyt-c) with mammalian cyts-c shows that the yeast protein has a five residue long N-terminal extension. A question arises: Does this N-terminal extension play any roles in the stability, structure, and folding of the yeast protein? To answer this question, in silico and in vitro studies were carried out on the wild type (WT) protein and its five deletants (Δ(?5/?5), Δ(?5/?4), Δ(?5/?3), Δ(?5/?2), and Δ(?5/?1) where Δ denotes the deletion and the numbers refer to the residues deleted, e.g. Δ(?5/?1) denotes the deletion of residues numbered from ?5 to ?1 (TEFKA), while Δ(?5/?2) denotes the deletion of resides numbered from ?5 to ?2 (TEFK) and so on). The main conclusion of the in silico study is that the order of stability of deletants and WT protein is Δ(?5/?4) > WT > Δ(?5/?3) > Δ(?5/?5) > Δ(?5/?1) ~ Δ(?5/?2). In vitro studies involved (i) measurements of thermodynamic stability of all proteins by differential scanning calorimetry and from sigmoidal curves of two different structural properties ([θ]222, a probe for detecting change in secondary structure, and Δε405, a probe for detecting alteration in the heme environment), and (ii) characterization of all proteins by various spectral properties. The main conclusions of the in vitro studies are as follows: (i) The order of thermodynamic stability of all proteins is in excellent agreement with that predicted by in silico studies, and (ii) A sequential deletion of the N-terminal extension has no effects on protein structure and folding.  相似文献   
954.
Meat-type chickens show high feed efficiency and have a very rapid growth rate compared with laying-type chickens. To clarify whether the type-specific difference in feed conversion efficiency is involved in mitochondrial bioenergetics, modular kinetic analysis was applied to oxidative phosphorylation in skeletal muscle mitochondria of both type chickens. Mitochondria from skeletal muscle of meat-type chickens showed greater substrate oxidation and phosphorylating activities, and less proton leak than those of the laying-type, resulting in a higher efficiency of oxidative phosphorylation. Gene expression and protein content of uncoupling protein (avUCP) but not adenine nucleotide translocase (avANT) gene expression were lower in skeletal muscle mitochondria of meat-type chickens than the laying-type. The current results regarding a higher efficiency of oxidative phosphorylation and UCP content may partially support the high feed efficiency of meat-type chickens.  相似文献   
955.
Mammalian mitochondrial initiation factor 3 (IF3mt) has a central region with homology to bacterial IF3. This homology region is preceded by an N-terminal extension and followed by a C-terminal extension. The role of these extensions on the binding of IF3mt to mitochondrial small ribosomal subunits (28S) was studied using derivatives in which the extensions had been deleted. The Kd for the binding of IF3mt to 28S subunits is ~30 nM. Removal of either the N- or C-terminal extension has almost no effect on this value. IF3mt has very weak interactions with the large subunit of the mitochondrial ribosome (39S) (Kd = 1.5 μM). However, deletion of the extensions results in derivatives with significant affinity for 39S subunits (Kd = 0.120.25 μM). IF3mt does not bind 55S monosomes, while the deletion derivative binds slightly to these particles. IF3mt is very effective in dissociating 55S ribosomes. Removal of the N-terminal extension has little effect on this activity. However, removal of the C-terminal extension leads to a complex dissociation pattern due to the high affinity of this derivative for 39S subunits. These data suggest that the extensions have evolved to ensure the proper dissociation of IF3mt from the 28S subunits upon 39S subunit joining.  相似文献   
956.
Spatial models for disease mapping should ideally account for covariates measured both at individual and area levels. The newly available “indiCAR” model fits the popular conditional autoregresssive (CAR) model by accommodating both individual and group level covariates while adjusting for spatial correlation in the disease rates. This algorithm has been shown to be effective but assumes log‐linear associations between individual level covariates and outcome. In many studies, the relationship between individual level covariates and the outcome may be non‐log‐linear, and methods to track such nonlinearity between individual level covariate and outcome in spatial regression modeling are not well developed. In this paper, we propose a new algorithm, smooth‐indiCAR, to fit an extension to the popular conditional autoregresssive model that can accommodate both linear and nonlinear individual level covariate effects while adjusting for group level covariates and spatial correlation in the disease rates. In this formulation, the effect of a continuous individual level covariate is accommodated via penalized splines. We describe a two‐step estimation procedure to obtain reliable estimates of individual and group level covariate effects where both individual and group level covariate effects are estimated separately. This distributed computing framework enhances its application in the Big Data domain with a large number of individual/group level covariates. We evaluate the performance of smooth‐indiCAR through simulation. Our results indicate that the smooth‐indiCAR method provides reliable estimates of all regression and random effect parameters. We illustrate our proposed methodology with an analysis of data on neutropenia admissions in New South Wales (NSW), Australia.  相似文献   
957.
Oxidative stress and mitochondrial dysfunction induced by metabolic insults are both hallmarks of various neurological disorders, whereby neuronal cells are severely affected by decreased glucose supply to the brain. Likely injured, astrocytes are important for neuronal homeostasis and therapeutic strategies should be directed towards improving astrocytic functions to improve brain's outcome. In the present study, we aimed to assess the actions of raloxifene, a selective estrogen receptor modulator in astrocytic cells under glucose deprivation. Our findings indicated that pretreatment with 1 µM raloxifene results in an increase in cell viability and attenuated nuclei fragmentation. Raloxifene's actions also rely on the reduction of oxidative stress and preservation of mitochondrial function in glucose-deprived astrocytic cells, suggesting the possible direct effects of this compound on mitochondria. In conclusion, our results demonstrate that raloxifene's protective actions might be mediated in part by astrocytes in the setting of a metabolic insult.  相似文献   
958.
959.
The present work deals with the development of an enzymatic treatment aiming at producing high-quality olive oil with increased phenolics content and antioxidant activity. Three different enzyme formulations, specifically pectinase, hemicellulase and cellulase (A), pectinase and hemicellulase (B), and only pectinase (C), were used either at three different level of each or in ternary and binary mixtures at a constant level. All of them were added to the olive paste (Italian cultivar Coratina) at the beginning of the malaxation step. Results demonstrated that an increased enzyme level led to higher phenolics content in the oils, and such an effect was found to be enzyme dependent, being greater when using formulation A, followed by formulations B and C. Two significant correlations were obtained between total polyphenols and o-diphenols contents versus antiradical power (R2 = 0.8743 and R2 = 0.8635, respectively), which pointed out the effectiveness of the proposed enzymatic treatment to produce olive oils characterized by low susceptibility to oxidation. A synergistic effect between the different enzymatic activities contained in the single formulations was observed by combining enzymes A and B. The ternary mixture was selected as the most efficient enzymatic system ensuring the highest phenolics content increase (40 and 37% for total polyphenols and o-diphenols contents, respectively) compared to the other enzymes when used at the same level.  相似文献   
960.
Non-healing skin ulcers are often resistant to most common therapies. Treatment with growth factors has been demonstrated to improve closure of chronic wounds. Here we investigate whether lyophilized culture supernatant of freshly isolated peripheral blood mononuclear cells (PBMC) is able to enhance wound healing. PBMC from healthy human individuals were prepared and cultured for 24 hours. Supernatants were collected, dialyzed and lyophilized (SECPBMC). Six mm punch biopsy wounds were set on the backs of C57BL/6J-mice and SECPBMC containing emulsion or controls were applied daily for three days. Morphology and neo-angiogenesis were analyzed by H&E-staining and CD31 immuno-staining, respectively. In vitro effects on diverse skin cells were investigated by migration assays, cell cycle analysis, and tube formation assay. Signaling pathways were analyzed by Western blot analysis. Application of SECPBMC on 6 mm punch biopsy wounds significantly enhanced wound closure. H&E staining of the wounds after 6 days revealed that wound healing was more advanced after application of SECPBMC containing emulsion. Furthermore, there was a massive increase in CD31 positive cells, indicating enhanced neo-angiogenesis. In primary human fibroblasts (FB) and keratinocytes (KC) migration but not proliferation was induced. In endothelial cells (EC) SECPBMC induced proliferation and tube-formation in a matrigel-assay. In addition, SECPBMC treatment of skin cells led to the induction of multiple signaling pathways involved in cell migration, proliferation and survival. In summary, we could show that emulsions containing the secretome of PBMC derived from healthy individuals accelerates wound healing in a mouse model and induce wound healing associated mechanisms in human primary skin cells. The formulation and use of such emulsions might therefore represent a possible novel option for the treatment of non-healing skin ulcers.  相似文献   
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