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941.
Rose MR Brix KA 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2006,361(1468):605-618
We present a review of neurological function in Gulf War veterans (GWV). Twenty-two studies were reviewed, including large hospitalization and registry studies, large population-based epidemiological studies, investigations of a single military unit, small uncontrolled studies of ill veterans and small controlled studies of veterans. In nearly all studies, neurological function was normal in most GWVs, except for a small proportion who were diagnosed with compression neuropathies (carpal tunnel syndrome or ulnar neuropathy). In the great majority of controlled studies, there were no differences in the rates of neurological abnormalities in GWVs and controls. In a national US study, the incidence of amyotrophic lateral sclerosis (ALS) seems to be significantly increased in GWVs, compared to the rate in controls. However, it is possible that military service, in general, might be associated with an increased risk of ALS, rather than Gulf War service in particular. Taken together, the conclusion is that if a neurological examination in a GWV is within normal limits, then extensive neurological testing is unlikely to diagnose occult neurological disorders. 相似文献
942.
Stijn Van Slycken Nele Witters Linda Meiresonne Erik Meers Ann Ruttens Pierre Van Peteghem 《International journal of phytoremediation》2013,15(7):677-689
Short rotation coppice (SRC) of willow and poplar might be a promising phytoremediation option since it uses fast growing, high biomass producing tree species with often a sufficient metal uptake. This study evaluates growth, metal uptake and extraction potentials of eight willow clones (Belders, Belgisch Rood, Christina, Inger, Jorr, Loden, Tora and Zwarte Driebast) on a metal-contaminated agricultural soil, with total cadmium (Cd) and zinc (Zn) concentrations of 6.5 ± 0.8 and 377 ± 69 mg kg?1 soil, respectively. Although, during the first cycle, on average generally low productivity levels (3.7 ton DM (dry matter) ha?1 y?1) were obtained on this sandy soil, certain clones exhibited quite acceptable productivity levels (e.g. Zwarte Driebast 12.5 ton DM ha?1 y?1). Even at low biomass productivity levels, SRC of willow showed promising removal potentials of 72 g Cd and 2.0 kg Zn ha?1 y?1, which is much higher than e.g. energy maize or rapeseed grown on the same soil. Cd and Zn removal can be increased by 40% if leaves are harvested as well. Nevertheless, nowadays the wood price remains the most critical factor in order to implement SRC as an acceptable, economically feasible alternative crop on metal-contaminated agricultural soils. 相似文献
943.
The GDP-fucose transporter SLC35C1 critically regulates the fucosylation of glycans. Elucidation of its structure-function relationships remains a challenge due to the lack of an appropriate mutant cell line. Here we report a novel Chinese hamster ovary (CHO) mutant, CHO-gmt5, generated by the zinc-finger nuclease technology, in which the Slc35c1 gene was knocked out from a previously reported CHO mutant that has a dysfunctional CMP-sialic acid transporter (CST) gene (Slc35a1). Consequently, CHO-gmt5 harbors double genetic defects in Slc35a1 and Slc35c1 and produces N-glycans deficient in both sialic acid and fucose. The structure-function relationships of SLC35C1 were studied using CHO-gmt5 cells. In contrast to the CST and UDP-galactose transporter, the C-terminal tail of SLC35C1 is not required for its Golgi localization but is essential for generating glycans that are recognized by a fucose-binding lectin, Aleuria aurantia lectin (AAL), suggesting an important role in the transport activity of SLC35C1. Furthermore, we found that this impact can be independently contributed by a cluster of three lysine residues and a Glu-Met (EM) sequence within the C terminus. We also showed that the conserved glycine residues at positions 180 and 277 of SLC35C1 have significant impacts on AAL binding to CHO-gmt5 cells, suggesting that these conserved glycine residues are required for the transport activity of Slc35 proteins. The absence of sialic acid and fucose on Fc N-glycan has been independently shown to enhance the antibody-dependent cellular cytotoxicity (ADCC) effect. By combining these features into one cell line, we postulate that CHO-gmt5 may represent a more advantageous cell line for the production of recombinant antibodies with enhanced ADCC effect. 相似文献
944.
Biomarkers of cancer can indicate the presence of disease and serve as therapeutic targets. Our goal is to develop an optical imaging approach using molecularly targeted contrast agents to assess several centimeters of mucosal surface for mapping expression of multiple biomarkers simultaneously with high spatial resolution. The ability to image biomarker expression level and heterogeneity in vivo would be extremely useful for clinical cancer research, patient selection of personalized medicine, and monitoring therapy. In this proof-of-concept ex vivo study, we examined correlation of neoplasia with two clinically relevant biomarkers: epidermal growth factor receptor (EGFR) and metabolic activity. Two hundred eighty-six unique locations in nine samples of freshly resected oral mucosa were imaged after topically applying optical imaging agents EGF-Alexa 647 (to target EGFR) and 2-(N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino)-2-deoxyglucose (to target metabolic activity). Quantitative features were calculated from resulting fluorescence images and compared with tissue histopathology maps. The EGF-Alexa 647 signal correlated well with EGFR expression as indicated by immunohistochemistry. A classification algorithm for presence of neoplasia based on the signal from both contrast agents resulted in an area under the curve of 0.83. Regions with a posterior probability from 0.80 to 1.00 contained more than 50% neoplasia 99% (84/85) of the time. This study demonstrates a proof-of-concept of how noninvasive optical imaging can be used as a tool to study expression levels of multiple biomarkers and their heterogeneity across a large mucosal surface and how biomarker characteristics correlate with presence of neoplasia. Applications of this approach include predicting regions with the highest likelihood of disease, elucidating the role of biomarker heterogeneity in cancer biology, and identifying patients who will respond to targeted therapy. 相似文献
945.
Haiwei Luo Bradley B Tolar Brandon K Swan Chuanlun L Zhang Ramunas Stepanauskas Mary Ann Moran James T Hollibaugh 《The ISME journal》2014,8(3):732-736
Previous studies based on analysis of amoA, 16S ribosomal RNA or accA gene sequences have established that marine Thaumarchaeota fall into two phylogenetically distinct groups corresponding to shallow- and deep-water clades, but it is not clear how water depth interacts with other environmental factors, including light, temperature and location, to affect this pattern of diversification. Earlier studies focused on single-gene distributions were not able to link phylogenetic structure to other aspects of functional adaptation. Here, we analyzed the genome content of 46 uncultivated single Thaumarchaeota cells sampled from epi- and mesopelagic waters of subtropical, temperate and polar oceans. Phylogenomic analysis showed that populations diverged by depth, as expected, and that mesopelagic populations from different locations were well mixed. Functional analysis showed that some traits, including putative DNA photolyase and catalase genes that may be related to adaptive mechanisms to reduce light-induced damage, were found exclusively in members of the epipelagic clade. Our analysis of partial genomes has thus confirmed the depth differentiation of Thaumarchaeota populations observed previously, consistent with the distribution of putative mechanisms to reduce light-induced damage in shallow- and deep-water populations. 相似文献
946.
Burke LE Styn MA Steenkiste AR Music E Warziski M Choo J 《Obesity (Silver Spring, Md.)》2006,14(11):2007-2017
Objective: The PREFER study objectives were to examine potential differences in weight loss during a standard behavioral intervention between subjects assigned to one of two calorie‐ and fat‐restricted diets [standard behavior treatment (SBT) and lacto‐ovo‐vegetarian ([SBT+LOV)], with or without regard to their preferred dietary treatment. This article reports the differences in outcomes between diet groups after the first 6 months of the intervention. Research Methods and Procedures: The study used a four‐group design. Subjects (n = 182) were randomized to a treatment preference group and then to a dietary treatment group. For this report, preference groups were combined to permit comparisons by dietary treatment only (SBT, n = 98; SBT+LOV, n = 84). Additional analyses compared SBT+LOV subjects who were 100% adherent (did not consume any meat, fish, or poultry, n = 47) to those who were <100% adherent (n = 24). Results: Significant differences were seen in the baseline to 6‐month change scores between the two groups for carbohydrate consumption (p = 0.013), protein consumption (p < 0.001), polyunsaturated‐to‐saturated fat ratio (p = 0.009), and low‐density lipoprotein‐cholesterol (LDL‐C) level (p = 0.013). Among SBT+LOV subjects, those who were 100% adherent experienced greater reductions in weight (p < 0.001), total cholesterol (p = 0.026), LDL‐C (p = 0.034), and glucose (p = 0.002) and consumed less fat (p = 0.030) compared with those who were <100% adherent. Discussion: Differences between dietary treatment groups at 6 months were minimal, most likely because one‐third of the SBT+LOV group did not follow the vegetarian diet and because both groups had the same calorie and fat restrictions. SBT+LOV subjects who were 100% adherent were more successful at both weight loss and cholesterol reduction than those who were <100% adherent, suggesting that vegetarian diets are efficacious for weight and cholesterol control. 相似文献
947.
Ruttens A Boulet J Weyens N Smeets K Adriaensen K Meers E Van Slycken S Tack F Meiresonne L Thewys T Witters N Carleer R Dupae J Vangronsveld J 《International journal of phytoremediation》2011,13(Z1):194-207
Phytoremediation, more precisely phytoextraction, has been placed forward as an environmental friendly remediation technique, that can gradually reduce increased soil metal concentrations, in particular the bioavailable fractions. The aim of this study was to investigate the possibilities of growing willows and poplars under short rotation coppice (SRC) on an acid, poor, sandy metal contaminated soil, to combine in this way soil remediation by phytoextraction on one hand, and production of biomass for energy purposes on the other. Above ground biomass productivities were low for poplars to moderate for willows, which was not surprising, taking into account the soil conditions that are not very favorable for growth of these trees. Calculated phytoextraction efficiency was much longer for poplars than these for willows. We calculated that for phytoextraction in this particular case it would take at least 36 years to reach the legal threshold values for cadmium, but in combination with production of feedstock for bioenergy processes, this type of land use can offer an alternative income for local farmers. Based on the data of the first growing cycle, for this particular case, SRC of willows should be recommended. 相似文献
948.
949.
Summary Mitochondrial creatine kinase (CK) purified from canine myocardium showed a single protein band on SDS-PAGE and was free of
MMCK. Its amino acid composition was different than MMCK or BBCK and did not react to antiserum to MMCK or BBCK. Using purified
mitochondrial, MM and BBCK, the velocity of reaction (V) was estimated for creatine phosphate (CP), creatine (C), adenosine
triphosphate (ATP) and adenosine diphosphate (ADP) over a wide range of concentrations including those at Vmax. The values for Km (mM/L) derived from Lineweaver-Burke plots are shown:
The affinity of mitochondrial CK for C is much greater than MMCK which is compatible with the energy shuttle hypothesis, namely
ATP is converted by mitochondrial CK to CP, and then diffuses to the myofibril for conversion to ATP for utilization. 相似文献
950.
Jianming Liu Anna Jonebring Jonas Hagström Ann-Christin Nyström Ann Lövgren 《The protein journal》2014,33(2):174-183
Recombinant human FIX concentrates (rhFIX) are essential in the treatment and prevention of bleeding in the bleeding disorder haemophilia B. However, due to the complex nature of FIX production yields are low which leads to high treatment costs. Here we report the production of rhFIX with substantially higher yield by co-expressing human FIX with GGCX (γ-glutamyl carboxylase), VKOR (vitamin K epoxide reductase) and furin (paired basic amino acid cleaving enzyme) in Chinese hamster ovary (CHO) cells. Our results show that controlled co-expression of GGCX with FIX is critical to obtain high rhFIX titre, and, that co-expression of VKOR further increased the yield of active rhFIX. Furin co-expression improved processing of the leader peptide of rhFIX but had a minor effect on yield of active rhFIX. The optimal expression level of GGCX was surprisingly low and required unusual engineering of expression vector elements. For VKOR and furin the control of expression was less critical and could be achieved by standard vector element. Using our expression vectors an rhFIX-producing clone with an expression level of up to 30 mg/L of active rhFIX was obtained. In addition an efficient single step purification method was developed to obtain pure and active rhFIX with up to 94 % yield. 相似文献