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1.
The Cumanians were originally Asian pastoral nomads who in the 13th century migrated to Hungary. We have examined mitochondrial DNA from members of the earliest Cumanian population in Hungary from two archeologically well-documented excavations and from 74 modern Hungarians from different rural locations in Hungary. Haplogroups were defined based on HVS I sequences and examinations of haplogroup-associated polymorphic sites of the protein coding region and of HVS II. To exclude contamination, some ancient DNA samples were cloned. A database was created from previously published mtDNA HVS I sequences (representing 2,615 individuals from different Asian and European populations) and 74 modem Hungarian sequences from the present study. This database was used to determine the relationships between the ancient Cumanians, modern Hungarians, and Eurasian populations and to estimate the genetic distances between these populations. We attempted to deduce the genetic trace of the migration of Cumanians. This study is the first ancient DNA characterization of an eastern pastoral nomad population that migrated into Europe. The results indicate that, while still possessing a Central Asian steppe culture, the Cumanians received a large admixture of maternal genes from more westerly populations before arriving in Hungary. A similar dilution of genetic, but not cultural, factors may have accompanied the settlement of other Asian nomads in Europe.  相似文献   
2.
Previous reports have suggested that protein disulfide isomerases (PDIs) have transglutaminase (TGase) activity. The structural basis of this reaction has not been revealed. We demonstrate here that Caenorhabditis elegans PDI-3 can function as a Ca(2+)-dependent TGase in assays based on modification of protein- and peptide-bound glutamine residues. By site-directed mutagenesis the second cysteine residue of the -CysGlyHisCys- motif in the thioredoxin domain of the enzyme protein was found to be the active site of the transamidation reaction and chemical modification of histidine in their motif blocked TGase activity.  相似文献   
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Rapid biocatalytic process development and intensification continues to be challenging with currently available methods. Chiral amino‐alcohols are of particular interest as they represent key industrial synthons for the production of complex molecules and optically pure pharmaceuticals. (2S,3R)‐2‐amino‐1,3,4‐butanetriol (ABT), a building block for the synthesis of protease inhibitors and detoxifying agents, can be synthesized from simple, non‐chiral starting materials, by coupling a transketolase‐ and a transaminase‐catalyzed reaction. However, until today, full conversion has not been shown and, typically, long reaction times are reported, making process modifications and improvement challenging. In this contribution, we present a novel microreactor‐based approach based on free enzymes, and we report for the first time full conversion of ABT in a coupled enzyme cascade for both batch and continuous‐flow systems. Using the compartmentalization of the reactions afforded by the microreactor cascade, we overcame inhibitory effects, increased the activity per unit volume, and optimized individual reaction conditions. The transketolase‐catalyzed reaction was completed in under 10 min with a volumetric activity of 3.25 U ml?1. Following optimization of the transaminase‐catalyzed reaction, a volumetric activity of 10.8 U ml?1 was attained which led to full conversion of the coupled reaction in 2 hr. The presented approach illustrates how continuous‐flow microreactors can be applied for the design and optimization of biocatalytic processes.
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BackgroundIt is anticipated that current and future preventive therapies will likely be more effective in the early stages of dementia, when everyday functioning is not affected. Accordingly the early identification of people at risk is particularly important. In most cases, when subjects visit an expert and are examined using neuropsychological tests, the disease has already been developed. Contrary to this cognitive games are played by healthy, well functioning elderly people, subjects who should be monitored for early signs. Further advantages of cognitive games are their accessibility and their cost-effectiveness.PurposeThe aim of the investigation was to show that computer games can help to identify those who are at risk. In order to validate games analysis was completed which measured the correlations between results of the ''Find the Pairs'' memory game and the volumes of the temporal brain regions previously found to be good predictors of later cognitive decline.ResultsThere was a correlation between the number of attempts and the time required to complete the memory game and the volume of the entorhinal cortex, the temporal pole, and the hippocampus. There was also a correlation between the results of the Paired Associates Learning (PAL) test and the memory game.ConclusionsThe results gathered support the initial hypothesis that healthy elderly subjects achieving lower scores in the memory game have increased level of atrophy in the temporal brain structures and showed a decreased performance in the PAL test. Based on these results it can be concluded that memory games may be useful in early screening for cognitive decline.  相似文献   
6.
In this work, the effects of osmotic stress and exogenous auxin (indole-3-butyric acid, IBA) on root morphology and nitric oxide (NO) generation in roots were compared in pea plants. Five-day-old plants were treated with 0, 10−3, 10−4, 10−5, 10−6, 10−7, 10−8 or 10−9  M IBA or with PEG 6000 at concentrations that determined 0, 50, 100, 200 or 400 mOsm in the medium, during 5 days. NO generation was examined by in situ and in vivo fluorescence method. Increasing concentrations of PEG as well as IBA resulted in shortening of primary root (PR), enhancement of lateral root (LR) number and significant increase of NO generation. Time-dependent investigations revealed that in the case of IBA treatments, the LR number increased in parallel with an intensified NO generation, while elongation of PR was not followed by changes in NO levels. Under osmotic stress, the time curve of NO development was distinct compared with that of IBA-treated roots, because significantly, the appearance of lateral initials was preceded by a transient burst of NO. This early phase of NO generation under osmotic stress was clearly distinguishable from that which accompanied LR initiation. It is concluded that osmotic stress and the presence of exogenous auxin resulted in partly similar root architecture but different time courses of NO synthesis. We suppose that the early phase of NO generation may fulfill a role in the osmotic stress-induced signalization process leading to the modification of root morphology.  相似文献   
7.
Site selective mono‐ and dimetalation methods have been developed for the functionalization of 1‐[(1,1′‐biphenyl)‐2‐yl]‐1H‐pyrrole. Optical resolution of the prepared 1‐[(3‐carboxy‐1,1′‐biphenyl)‐2‐yl]pyrrole‐2‐carboxylic acid provided new atropisomeric 1‐arylpyrrole derivatives. The absolute configuration of the pure dicarboxylic acid enantiomers was determined by single crystal X‐ray diffraction and CD spectroscopy. Chirality 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
8.
This study examined the size-dependent scavenging behaviour of black bullheads Ameiurus melas under laboratory conditions, using common bleak Alburnus alburnus and pumpkinseed Lepomis gibbosus carcasses. Video camera observations showed that the activity of A. melas was higher at night, but substantial daytime activity was also recorded. Larger A. melas were more active than their smaller conspecifics, especially at night. All size classes exhibited a well-defined sequence of consuming different parts of the carcasses independent of size, but larger individuals tended to consume carcasses more efficiently. Carcasses of the softer-bodied A. alburnus were consumed more readily than those of the bonier L. gibbosus, independent of size. This scavenging behaviour of A. melas might facilitate the invasion success of the species.  相似文献   
9.
Human ovarian follicular fluids and sera obtained from women pre-treated for in vitro fertilization (IVF) were investigated by capillary zone electrophoresis. Comparison of the matching physiological liquids showed substantial differences in the electrophoretic patterns. Significant decrease in the alpha(1)- and gamma-fractions of follicular fluids of every woman were observed, whereas other fractions of the samples did not show such alterations. Since follicular fluid is a product of both, secretion by granulosa cells and diffusion from the theca capillaries, we can assume that the forced production of follicular fluid upon hormone stimulation (with gonadotropin releasing hormone (GnRH), follicle stimulating hormone (FSH) and corionic gonadotroph hormone (hCG)) may play role in the uneven presence of the proteins.  相似文献   
10.
TDP‐43 (encoded by the gene TARDBP) is an RNA binding protein central to the pathogenesis of amyotrophic lateral sclerosis (ALS). However, how TARDBP mutations trigger pathogenesis remains unknown. Here, we use novel mouse mutants carrying point mutations in endogenous Tardbp to dissect TDP‐43 function at physiological levels both in vitro and in vivo. Interestingly, we find that mutations within the C‐terminal domain of TDP‐43 lead to a gain of splicing function. Using two different strains, we are able to separate TDP‐43 loss‐ and gain‐of‐function effects. TDP‐43 gain‐of‐function effects in these mice reveal a novel category of splicing events controlled by TDP‐43, referred to as “skiptic” exons, in which skipping of constitutive exons causes changes in gene expression. In vivo, this gain‐of‐function mutation in endogenous Tardbp causes an adult‐onset neuromuscular phenotype accompanied by motor neuron loss and neurodegenerative changes. Furthermore, we have validated the splicing gain‐of‐function and skiptic exons in ALS patient‐derived cells. Our findings provide a novel pathogenic mechanism and highlight how TDP‐43 gain of function and loss of function affect RNA processing differently, suggesting they may act at different disease stages.  相似文献   
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