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61.
A gram-negative, moderately halophilic bacterium was isolated from ?amalt? Saltern area, located in the Aegean Region of Turkey. Analysis of its 16S rRNA gene sequence and physiological characteristics showed that this strain belonged to the genus Halomonas ; hence, it was designated as Halomonas sp. strain AAD12. The isolate tolerated up to 800 mg?L(-1) phenol; however, at elevated concentrations, phenol severely retarded cell growth. The increase in lag phase with increasing phenol concentrations indicated that the microorganism was undergoing serious adaptative changes. To understand the physiological responses of Halomonas sp. strain AAD12 to phenol, a 2-dimensional electrophoresis approach combined with mass spectrometric analysis was used. This approach showed that the expression of 14 protein spots were altered as phenol concentration increased from 200 to 800 mg?L(-1). Among the identified proteins were those involved in protein biosynthesis, energy, transport, and stress metabolism. So far, this is the first study on phenolic adaptation of a gram-negative, moderately halophilic bacteria using proteomic tools. The results provided new insights for understanding the general mechanism used by moderately halophilic bacteria to tolerate phenol and suggested the potential for using these microorganisms in bioremediation.  相似文献   
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Substituted polyaniline/chitosan (sPANI/Ch) composites were chemically synthesized in H2SO4 and CH3COOH synthesis media. Structural and physical properties of the composites were characterized by using FTIR, SEM, TGA, UV–vis, XRD techniques, and conductivity measurements. The effect of synthesis media on morphology, thermal stability, conductivity, and crystalline properties was investigated. Chemical interactions between substituted polyanilines and chitosan were explained using FTIR spectra results. The different morphological surfaces were observed in SEM images of the composites. The size of the substituted polyaniline/chitosan (sPANI/Ch) composites was in nanoscale, and the composites synthesized in acetic acid media showed smaller structures than those of H2SO4 media and pure chitosan. It was interpreted from XRD results that the composites have amorphous structure and the PNEANI/Ch–CH3COOH composite has the highest crystallinity.  相似文献   
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The therapeutic effects of melatonin or vitamin E plus Se (vE + Se) on the restrain of the heroin withdrawal-induced oxidative stress were studied. For this, rats were divided into ten groups. The rats were injected by fixed or variable doses of heroin for 16 consecutive days, and naloxone was given 1 h after the last heroin injection. One hour after naloxone administration, some groups were treated with melatonin or vE + Se. After 1 h this, blood samples were taken, and the levels of malondialdehyde (MDA) and reduced glutathione (GSH) in whole blood, ascorbic acid, α-tocopherol, retinol, β-carotene, nitrite, nitrate, and ceruloplasmin levels in the serum were measured. Our findings showed that, naloxone administration precipitated the heroin withdrawal. This also increased the level of MDA and decreased the levels of GSH in blood. Melatonin or vE + Se administration prevented the rise in MDA levels and increased the GSH levels. On the other hand, there were some significant differences between α-tocopherol, retinol, β-carotene, nitrite, nitrate, and ceruloplasmin levels of experimental groups. Results of present study showed that heroin withdrawal increased the lipid peroxidation and depressed endogenous antioxidative systems. Additionally, melatonin or vE + Se administrations prevented lipid peroxidation and augmented endogenous antioxidant defense systems.  相似文献   
64.
Neuronal exocytosis is mediated by soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins. Before fusion, SNARE proteins form complexes bridging the membrane followed by assembly toward the C-terminal membrane anchors, thus initiating membrane fusion. After fusion, the SNARE complex is disassembled by the AAA-ATPase N-ethylmaleimide-sensitive factor that requires the cofactor α-SNAP to first bind to the assembled SNARE complex. Using chromaffin granules and liposomes we now show that α-SNAP on its own interferes with the zippering of membrane-anchored SNARE complexes midway through the zippering reaction, arresting SNAREs in a partially assembled trans-complex and preventing fusion. Intriguingly, the interference does not result in an inhibitory effect on synaptic vesicles, suggesting that membrane properties also influence the final outcome of α-SNAP interference with SNARE zippering. We suggest that binding of α-SNAP to the SNARE complex affects the ability of the SNARE complex to harness energy or transmit force to the membrane.  相似文献   
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Three flavonoid glycosides were isolated and characterized, together with a further 13 substances belonging to various classes of compounds, in particular two phenolic acids, a coumarin, a sugar and nine flavonoids from the flowered aerial parts of Centaurea pseudoscabiosa subsp. pseudoscabiosa Boiss. et Buhse (Asteraceae). Some considerations about their evolutionary meaning are provided.  相似文献   
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International Journal of Peptide Research and Therapeutics - Vascular endothelial growth factor 165 (VEGF165) is the best characterized member and most potent endothelial cell mitogenic factor...  相似文献   
67.
Reconstruction of orbital floor fracture using solvent-preserved bone graft   总被引:8,自引:0,他引:8  
The orbital floor is one of the most frequently damaged parts of the maxillofacial skeleton during facial trauma. Unfavorable aesthetic and functional outcomes are frequent when it is treated inadequately. The treatment consists of spanning the floor defect with a material that can provide structural support and restore the orbital volume. This material should also be biocompatible with the surrounding tissues and easily reshaped to fit the orbital floor. Although various autografts or synthetic materials have been used, there is still no consensus on the ideal reconstruction method of orbital floor defects. This study evaluated the applicability of solvent-preserved cadaveric cranial bone graft and its preliminary results in the reconstruction of the orbital floor fractures. Twenty-five orbital floor fractures of 21 patients who underwent surgical repair with cadaveric bone graft during a 2-year period were included in this study. Pure blowout fractures were determined in nine patients, whereas 12 patients had other accompanying maxillofacial fractures. Of the 21 patients, 14 had clinically evident diplopia (66.7 percent), 12 of them had enophthalmos (57.1 percent), and two of them had gaze restriction preoperatively. Reconstruction of the floor of the orbit was performed following either the subciliary or the transconjunctival approach. A cranial allograft was placed over the defect after sufficient exposure. The mean follow-up period was 9 months. Postoperative diplopia, enophthalmos, eye motility, cosmetic appearance, and complications were documented. None of the patients had any evidence of diplopia, limited eye movement, inflammatory reactions in soft tissues, infection, or graft extrusion in the postoperative period. Providing sufficient orbital volume, no graft resorption was detected in computed tomography scan controls. None of the implants required removal for any reason. Enophthalmos was seen in one patient, and temporary scleral show lasting up to 3 to 6 weeks was detected in another three patients. Satisfactory cosmetic results were obtained in all patients. This study showed that solvent-preserved bone, which is a nonsynthetic, human-originated, processed bioimplant, can be safely used in orbital floor repair and can be considered as another reliable treatment alternative.  相似文献   
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The paradigm of a single gene associated with one specific phenotype and mode of inheritance has been repeatedly challenged. Genotype-phenotype correlations can often be traced to different mutation types, localization of the variants in distinct protein domains, or the trigger of or escape from nonsense-mediated decay. Using whole-exome sequencing, we identified homozygous variants in EMC1 that segregated with a phenotype of developmental delay, hypotonia, scoliosis, and cerebellar atrophy in three families. In addition, a de novo heterozygous EMC1 variant was seen in an individual with a similar clinical and MRI imaging phenotype. EMC1 encodes a member of the endoplasmic reticulum (ER)-membrane protein complex (EMC), an evolutionarily conserved complex that has been proposed to have multiple roles in ER-associated degradation, ER-mitochondria tethering, and proper assembly of multi-pass transmembrane proteins. Perturbations of protein folding and organelle crosstalk have been implicated in neurodegenerative processes including cerebellar atrophy. We propose EMC1 as a gene in which either biallelic or monoallelic variants might lead to a syndrome including intellectual disability and preferential degeneration of the cerebellum.  相似文献   
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