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21.
Hyperacute rejection (HAR) is the first critical immunological hurdle that must be addressed in order to develop xenogeneic organs for human transplantation. In the area of cell-based xenotransplant therapies, natural antibodies (XNA) and complement have also been considered barriers to successful engraftment. Transgenic expression of human complement inhibitors in donor cells and organs has significantly prolonged the survival of xenografts. However, expression of complement inhibitors without eliminating xenogeneic natural antibody (XNA) reactivity may provide insufficient protection for clinical application. An approach designed to prevent XNA reactivity during HAR is the expression of human alpha1, 2-fucosyltransferase (H-transferase, HT). H-transferase expression modifies the cell surface carbohydrate phenotype of the xenogeneic cell, resulting in the expression of the universal donor O antigen and a concomitant reduction in the expression of the antigenic Galalpha1,3-Gal epitope. We have engineered various transgenic pig lines that express HT in different cells and tissues, including the vascular endothelium. We demonstrate that in two different HT transgenic lines containing two different HT promoter constructs, expression can be differentially regulated in a constitutive and cytokine-inducible manner. The transgenic expression of HT results in a significant reduction in the expression of the Galalpha1,3-Gal epitope, reduced XNA reactivity, and an increased resistance to human serum-mediated cytolysis. Transgenic pigs that express H-transferase promise to become key components for the development of xenogeneic cells and organs for human transplantation.  相似文献   
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We describe the extra bony elements, plates, and osteoderms present in species of the genus Brachycephalus. Samples of eight species of Brachycephalus, including seven populations of Brachycephalus ephippium, were examined. The large additional elements associated with the skull (parotic plate) and vertebrae (vertebral and paravertebral plates) all comprise intramembranous bone, similar to that of the frontoparietal or nasal bones of the skull of most of frogs. Additionally, in the dermis of one unnamed species, we discovered and described true osteoderms. We discuss the morphological nature and diversity of theses elements and their importance as evidence of phylogenetic relationship within Brachycephalus. In summary, three distinct conditions of extra bony elements occur in the genus Brachycephalus: (1) bony plates may be present or absent in species of the genus; (2) a few, small bony plates may be developed and these may be represented by (a) paravertebral plates small and restricted to the distal ends of the transverse processes of the presacral IV, (b) parotic plates small and not covering the tops of the squamosals, and (c) ornamented spinal plates on all vertebrae; and (3) well‐developed bony plates may be present as (a) paravertebral plates forming a ‘bone‐shield’ on the dorsal surface of the trunk, ornamented, and visible through the integument, (b) parotic plates covering the tops of the squamosals, and (c) spinal plates associated with all vertebrae, and ornamented on vertebrate I–VI. Although the phenomenon of miniaturization may be associated with the appearance of new elements in at least some of the species in the genus, the traditional rule may not be universally applicable. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 752–767.  相似文献   
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Reference intervals are commonly considered to allow for between-laboratory bias. The RCPAQAP Liquid Serum Chemistry Program has collected data on laboratory measurements as well as reference intervals. This allows assessment of the between-laboratory variation in results, reference intervals and the information transmitted by the combination of these factors. For the majority of common chemistry analytes, the between-laboratory variation in reference intervals is greater than the variation in results. Additionally the reference interval variation is generally not related to bias between the results. Use of common reference intervals, either as an average of the current intervals in use, or the intervals proposed by the AACB Harmonisation Group, improved the variation seen in the information produced by different laboratories.  相似文献   
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Fourteen elite sorghum lines were evaluated for their resistance to Striga hermonthica at three locations in Nigeria and Mali. Results showed that many of the lines especially MALISOR 84-1, SAMSORG 41, 97-SB-F5DT-64 (Keninkédié) and the check SRN 39 remained resistant to Striga in all locations with low emerged Striga counts, while SAMSORG 14 had the highest Striga infestation in all locations. Considerable variation in reaction to Striga infestation was observed on Séguètana, 97-SB-F5DT-63 (Wasa), 97-SB-F5DT-65, CMDT 38, CMDT 39 and CMDT 45 which were susceptible to Striga at Samaru, Nigeria but were resistant to Striga at both locations in Mali. Based on low Striga resistance and high grain yield, lines MALISOR 84-1, SAMSORG 41, 97-SB-F5DT-64, 97-SB-F5DT-65, CMDT 39 and SAMSORT 14 have been nominated for wider evaluation across more West African countries.  相似文献   
27.

Background

Anxiety and depression in children and adolescents are undertreated. Computer- and Internet-based cognitive behavioral treatments (cCBT) may be an attractive treatment alternative to regular face-to-face treatment.This meta-analysis aims to evaluate whether cCBT is effective for treating symptoms of anxiety and depression in youth.

Methods and Findings

We conducted systematic searches in bibliographical databases (Pubmed, Cochrane controlled trial register, PsychInfo) up to December 4, 2013. Only randomized controlled trials in which a computer-, Internet- or mobile-based cognitive behavioral intervention targeting either depression, anxiety or both in children or adolescents up to the age of 25 were compared to a control condition were selected. We employed a random-effects pooling model in overall effect analyses and a mixed effect model for sub-group analyses. Searches resulted in identifying 13 randomized trials, including 796 children and adolescents that met inclusion criteria. Seven studies were directed at treating anxiety, four studies at depression, and two were of a transdiagnostic nature, targeting both anxiety and depression. The overall mean effect size (Hedges’ g) of cCBT on symptoms of anxiety or depression at post-test was g=0.72 (95% CI:0.55-0.90, numbers needed to be treated (NNT)=2.56). Heterogeneity was low (I²=20.14%, 95% CI: 0-58%). The superiority of cCBT over controls was evident for interventions targeting anxiety (g=0.68; 95% CI: 0.45-0.92; p < .001; NNT=2.70) and for interventions targeting depression (g=0.76; 95% CI: 0.41-0.12; p < .001; NNT=2.44) as well as for transdiagnostic interventions (g=0.94; 95% CI: 0.23-2.66; p < .001; NNT=2.60).

Conclusions

Results provide evidence for the efficacy of cCBT in the treatment of anxiety and depressive symptoms in youth. Hence, such interventions may be a promising treatment alternative when evidence based face-to-face treatment is not feasible. Future studies should examine long-term effects of treatments and should focus on obtaining patient-level data from existing studies, to perform an individual patient data meta-analysis.  相似文献   
28.
The purpose of this investigation was to evaluate acquisition and inoculation (together, transmission) efficiency of Candidatus Liberibacter asiaticus (Las), the pathogen associated with citrus huanglongbing (HLB) by the Asian citrus psyllid, Diaphorina citri (Kuwayama) (Hemiptera: Psyllidae). In laboratory studies, nymphs reared on Las infected plants were more likely to acquire the bacterium than adults. Acquisition by nymphs ranged from 60 to 100%, whereas acquisition by adults only reached 40% after 5 wk of feeding on Las-infected plants. Similar rates of pathogen acquisition by psyllids after nymphal and adult feeding were observed in the field. Transmission of Las from parent to offspring (transovarial) occurred at a rate of 2-6%. One year after psyllid inoculations, successful transmission by individual D. citri ranged from 4 to 10%, whereas groups of 100 or more D. citri transmitted the pathogen at a rate of approximately 88%. In addition, the proportion of Las-positive adult psyllids, determined using quantitative real-time polymerase chain reaction, decreased over time when held on healthy plants. Due to the low rate of pathogen acquisition and long time period required for successful inoculation by adult D. citri, experiments designed to determine the latent period required for replication and successful inoculation of Las by D. citri did not result in Las-infected plants after >1 yr of incubation after inoculation. Collectively, these results indicate that adult D. citri which acquire the HLB pathogen as adults are poor vectors of the pathogen compared with adults that acquired the pathogen as nymphs.  相似文献   
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ABSTRACT. Proteins of the membrane skeleton of Euglena gracilis were extensively phosphorylated in vivo and in vitro after incubation with [32P]-orthophosphate or γ-[32P] ATP. Endogenous protein threonine/serine activity phosphorylated the major membrane skeletal proteins (articulins) and the putative integral membrane protein (IP39) anchor for articulins. The latter was also the major target for endogenous protein tyrosine kinase activity. A cytoplasmic domain of IP39 was specifically phosphorylated, and removal of this domain with papain eliminated the radiolabeled phosphoamino acids and eliminated or radically shifted the PI of the multiple isoforms of IP39. In gel kinase assays IP39 autophosphorylated and a 25 kDa protein which does not autophosphorylate was identified as a threonine/serine (casein) kinase. Plasma membranes from the membrane skeletal protein complex contained threonine/serine (casein) kinase activity, and cross-linking experiments suggested that IP39 was the likely source for this membrane activity. pH optima, cation requirements and heparin sensitivity of the detergent solubilized membrane activity were determined. Together these results suggest that protein kinases may be important modulators of protein assembly and function of the membrane skeleton of these protistan cells.  相似文献   
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