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101.
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The production of enriched fructose syrups and ethanol from beet molasses using Saccharomyces cerevisiae ATCC 36858 was studied. In batch experiments with a total sugar concentration between 94.9 and 312.4 g/L, the fructose yield was above 93% of the theoretical value. The ethanol yield and volumetric productivity in the beet molasses media with sugar concentration below 276.2 g/L were in the range of 59-76% of theoretical value and between 0.48 and 2.97 g of ethanol/(L x h), respectively. The fructose fraction in the carbohydrates content of the produced syrups was more than 95% when the total initial sugar concentration in the medium was below 242.0 g/L. Some oligosaccharides and glycerol were also produced in all tested media. Raffinose and the produced oligosaccharides were completely consumed by the end of the fermentation process when the total initial sugar concentration was below 190.1 g/L. The glycerol concentration was below 16.1 g/L. The results could be useful for a potential industrial production of ethanol and high-fructose syrup from sugar beet molasses.  相似文献   
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Treatment of infected tibial nonunion with bone defect represents a challenge for every orthopaedic surgeon. Various methods of treatment have been described for nonunions with infection, bone loss or both. One of them is the central bone grafting technique, which is a safe and effective treatment for nonunions of the tibia. The technique involves placement of autogenous cancellous bone from the iliac crest on the anterior surface of the interosseous membrane with the aim of creating a tibiofibular synostosis. We present the results of uncontrolled, retrospective and continuous series of ten patients treated by a central bone grafting technique for infected tibial nonunion with bone loss. Mean follow-up period was 12 (10-15) years. Most injuries were a result of war injuries. Clinically and radiologically confirmed bony healing with total consolidation of the graft was achieved in all patients within a period of 10-12 months without further bone grafting. The newly-formed bone mass was able to fulfil the mechanical and functional demands of everyday life activities. Once again, the central bone grafting technique has shown to be a safe, reliable and effective method of treatment for infected tibial nonunion with bone defect.  相似文献   
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Dendrites and dendritic spine density regress extensively during aging in rats housed under standard conditions (SC), which can be ameliorated by housing in the enriched environment (EE). This event is particularly pronounced on neurons where high rates of plasticity are conceivable, such as on projection neurons of archicortical regions of dentate gyrus'. However, effects of EE on neocortical projection neurons are still poorly understood. Therefore, we investigated the effect of EE housing on a deep layer III (L3) and layer V pyramidal cell (L5) morphology in the associative occipital neocortex of male Sprague-Dawley rats at 24 months of age. Rats were randomly distributed in two groups and reared under either SC (n=5) or EE conditions (n=6) for 26 days. In depth quantitative analysis of dendritic tree morphology and spine density on occipital projection neurons, from Golgi-Cox stained sections, showed similar trend in both EE occipital layers L3 and L5. Significant increase was found in total number of dendritic segments (L3 - 37.5 %, L5 - 33 %) and in dendritic diameter of intermediate segments (for more than 20 %), while increase in total spine number was around the level of significance (p>0.55; L3 - 30 %, L5 - 64 %). These findings suggest an outgrowth of new dendritic segments, When compared to archicortical region of dentate gyrus, effects of aging in the associative occipital cortex were less pronounced. Taken together, these findings suggest that structures being more affected by the aging process are more susceptible to the environmental enrichment in old age.  相似文献   
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Twelve new thiazolidinones were synthesized and, together with 41 previously synthesized thiazolidinones, evaluated for inhibitory activity against deoxyribonuclease I (DNase I) in vitro. Ten compounds inhibited commercial bovine pancreatic DNase I with an IC50 below 200 μM and showed to be more potent DNase I inhibitors than crystal violet (IC50 = 365.90 ± 47.33 μM), used as a positive control. Moreover, three compounds were active against DNase I in rat liver homogenate, having an IC50 below 200 μM. (3-Methyl-1,4-dioxothiazolidin-2-ylidene)-N-(2-phenylethyl)ethanamide ( 41 ) exhibited the most potent DNase I inhibition against both commercial and rat liver DNase I with IC50 values of 115.96 ± 11.70 and 151.36 ± 15.85 μM, respectively. Site Finder and molecular docking defined the thiazolidinones interactions with the most important catalytic residues of DNase I, including the H-acceptor interaction with residues His 134 and His 252 and/or H-donor interaction with residues Glu 39 and Asp 168. The three most active compounds against both commercial and rat liver DNase I ( 31 , 38 , and 41 ) exhibited favorable physico-chemical, pharmacokinetic, and toxicological properties. These observations could be utilized to guide the rational design and optimization of novel thiazolidinone inhibitors. Thiazolidinones as novel DNase I inhibitors could have potential therapeutic applications due to the significant involvement of DNase I in the pathophysiology of many disease conditions.  相似文献   
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Equinatoxin II is a cysteineless pore-forming protein from the sea anemone Actinia equina. It readily creates pores in membranes containing sphingomyelin. Its topology when bound in lipid membranes has been studied using cysteine-scanning mutagenesis. At approximately every tenth residue, a cysteine was introduced. Nineteen single cysteine mutants were produced in Escherichia coli and purified. The accessibility of the thiol groups in lipid-embedded cysteine mutants was studied by reaction with biotin maleimide. Most of the mutants were modified, except those with cysteines at positions 105 and 114. Mutants R144C and S160C were modified only at high concentrations of the probe. Similar results were obtained if membrane-bound biotinylated mutants were tested for avidin binding, but in this case three more mutants gave a negative result: S1C, S13C and K43C. Furthermore, mutants S1C, S13C, K20C, K43C and S95C reacted with biotin only after insertion into the lipid, suggesting that they were involved in major conformational changes occurring upon membrane binding. These results were further confirmed by labeling the mutants with acrylodan, a polarity-sensitive fluorescent probe. When labeled mutants were combined with vesicles, the following mutants exhibited blue-shifts, indicating the transfer of acrylodan into a hydrophobic environment: S13C, K20C, S105C, S114C, R120C, R144C and S160C. The overall results suggest that at least two regions are embedded within the lipid membrane: the N-terminal 13-20 region, probably forming an amphiphilic helix, and the tryptophan-rich 105-120 region. Arg144, Ser160 and residues nearby could be involved in making contacts with lipid headgroups. The association with the membrane appears to be unique and different from that of bacterial pore-forming proteins and therefore equinatoxin II may serve as a model for eukaryotic channel-forming toxins.  相似文献   
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OBJECTIVE: The clinical and molecular data of a patient with triple A syndrome are reported. PATIENT: A 21-year-old male who was diagnosed for adrenal insufficiency at the age of 2 years after a severe attack of adrenal crisis. At the age of 4 years, achalasia and alacrima were diagnosed. Puberty started at the age of 17 years. At the same time, symptoms of central, peripheral, and autonomic nervous system dysfunction were noted. Later on, at the age of 20 years, a bone age delay of 6 years and severe osteoporosis was diagnosed. RESULTS: A compound heterozygous AAAS mutation consisting of two mutations was found: a C > T transition in exon 7 resulting in a change of arginine at amino acid position 194 into a stop codon (Arg194X) at one allele, and a C > T transition in exon 12 resulting in a change of glutamine at amino acid position 387 into a stop codon (Gln387X) on the other allele. CONCLUSION: The mutation in exon 7 (p.R194X) of the AAAS gene is a novel mutation which has not been found in any other family so far, whereas the second was already found in some other families. This case adds to the clinical and molecular spectrum of triple A syndrome and may provide a new insight into the functions of AAAS gene.  相似文献   
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