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111.
Myotonia is a symptom of various genetic and acquired skeletal muscular disorders and is characterized by hyperexcitability of the sarcolemma. Here, we have performed a comparative proteomic study of the genetic mouse models ADR, MTO and MTO*5J of human congenital myotonia in order to determine myotonia-specific changes in the global protein complement of gastrocnemius muscle. Proteomic analyses of myotonia in the mouse, which is caused by mutations in the gene encoding the muscular chloride channel Clc1, revealed a generally perturbed protein expression pattern in severely affected ADR and MTO muscle, but less pronounced alterations in mildly diseased MTO*5J mice. Alterations were found in major metabolic pathways, the contractile machinery, ion handling elements, the cellular stress response and cell signaling mechanisms, clearly confirming a glycolytic-to-oxidative transformation process in myotonic fast muscle. In the long-term, a detailed biomarker signature of myotonia will improve our understanding of the pathobiochemical processes underlying this disorder and be helpful in determining how a single mutation in a tissue-specific gene can trigger severe downstream effects on the expression levels of a very large number of genes in contractile tissues. 相似文献
112.
From the first days of life, humans preferentially orient towards upright faces, likely reflecting innate subcortical mechanisms. Here, we show that binocular rivalry can reveal face detection mechanisms in adults that are surprisingly similar to inborn face detection mechanism. We used continuous flash suppression (CFS), a variant of binocular rivalry, to render stimuli invisible at the beginning of each trial and measured the time upright and inverted stimuli needed to overcome such interocular suppression. Critically, specific stimulus properties previously shown to modulate looking preferences in neonates similarly modulated adults' awareness of faces presented during CFS. First, the advantage of upright faces in overcoming CFS was strongly modulated by contrast polarity and direction of illumination. Second, schematic patterns consisting of three dark blobs were suppressed for shorter durations when the arrangement of these blobs respected the face-like configuration of the eyes and the mouth, and this effect was modulated by contrast polarity. No such effects were obtained in a binocular control experiment not involving CFS, suggesting a crucial role for face-sensitive mechanisms operating outside of conscious awareness. These findings indicate that visual awareness of faces in adults is governed by perceptual mechanisms that are sensitive to similar stimulus properties as those modulating newborns' face preferences. 相似文献
113.
Production of reactive oxygen species represents a fundamental innate defense against microbes in a diversity of host organisms. Oxidative stress, amongst others, converts peptidyl and free methionine to a mixture of methionine-S- (Met-S-SO) and methionine-R-sulfoxides (Met-R-SO). To cope with such oxidative damage, methionine sulfoxide reductases MsrA and MsrB are known to reduce MetSOs, the former being specific for the S-form and the latter being specific for the R-form. However, at present the role of methionine sulfoxide reductases in the pathogenesis of intracellular bacterial pathogens has not been fully detailed. Here we show that deletion of msrA in the facultative intracellular pathogen Salmonella (S.) enterica serovar Typhimurium increased susceptibility to exogenous H(2)O(2), and reduced bacterial replication inside activated macrophages, and in mice. In contrast, a ΔmsrB mutant showed the wild type phenotype. Recombinant MsrA was active against free and peptidyl Met-S-SO, whereas recombinant MsrB was only weakly active and specific for peptidyl Met-R-SO. This raised the question of whether an additional Met-R-SO reductase could play a role in the oxidative stress response of S. Typhimurium. MsrC is a methionine sulfoxide reductase previously shown to be specific for free Met-R-SO in Escherichia (E.) coli. We tested a ΔmsrC single mutant and a ΔmsrBΔmsrC double mutant under various stress conditions, and found that MsrC is essential for survival of S. Typhimurium following exposure to H(2)O(2,) as well as for growth in macrophages, and in mice. Hence, this study demonstrates that all three methionine sulfoxide reductases, MsrA, MsrB and MsrC, facilitate growth of a canonical intracellular pathogen during infection. Interestingly MsrC is specific for the repair of free methionine sulfoxide, pointing to an important role of this pathway in the oxidative stress response of Salmonella Typhimurium. 相似文献
114.
Measuring Eco-efficiency of Production with Data Envelopment Analysis 总被引:12,自引:0,他引:12
Aggregation of environmental pressures into a single environmental damage index is a major challenge of eco-efficiency measurement. This article examines how the data envelopment analysis (DEA) method can be adapted for this purpose. DEA accounts for substitution possibilities between different natural resources and emissions and does not require subjective judgment about the weights. Although DEA does not require subjective or normative judgment, soft weight restrictions can be incorporated into the framework. The proposed approach is illustrated by an application to assessing ecoefficiency of road transportation in the three largest towns of eastern Finland. 相似文献
115.
Kotilainen P Airas L Kojo T Kurki T Kataja K Minn H Nuutila P 《Neuro endocrinology letters》2005,26(1):67-68
Our patient developed Riedel's thyroiditis soon after having an exacerbation of multiple sclerosis (MS). MS has been associated with other autoimmune diseases, including thyroiditis, and both Hashimoto's thyroiditis and subacute thyroiditis have been described in connection with MS. Yet, we are not aware of any other patient reported to have concomitant MS and Riedel's thyroiditis. The association between MS and Riedel's thyroiditis remains obscure but may reflect an autoimmune disorder common to both diseases. 相似文献
116.
Cyclosporin A (CsA) generates superoxide in smooth muscle cells. Our earlier studies have demonstrated that the increase in the vasopressin type 1 receptor induced in vascular smooth muscle cells in the presence of CsA is probably due to superoxide (Krauskopf et al., J Biol Chem 278, 41685-41690, 2003). This increase in vasopressin receptor is likely at the base of increased vascular responsiveness to vasoconstrictor hormones and hypertension induced by CsA. Here, we demonstrate that CsA produces superoxide. In addition, our data show that superoxide generation does not originate from the major cellular superoxide generating systems NAD(P)H oxidase or xanthine oxidase. Our results suggest that the side effects of CsA could be diminished with the help of SOD mimetic drugs. 相似文献
117.
Krohn K Stanescu I Blazevic V Vesikari T Ranki A Ustav M 《Microbes and infection / Institut Pasteur》2005,7(14):1405-1413
A potent DNA vaccine against HIV, combining a vector that takes advantage of the segregation and compartmentalization effect of bovine papilloma virus E2 protein with MultiHIV insert, expressing a fusion gene coding for the non-structural and structural proteins was developed and tested for immunogenicity in mice and humans. 相似文献
118.
Wahlroos Tony Susi Petri Solovyev Andrej Dorokhov Yurii Morozov Sergeyi Atabekov Josif Korpela Timo 《Molecular breeding : new strategies in plant improvement》2005,14(4):455-462
An approach that enables the increase of the quantity of a specific amino acid in crop plants is reported. Oleosin gene from Arabidopsis thaliana or 30K movement protein gene of Tobacco mosaic virus (TMV; genus Tobamovirus) were cloned under the control of napin or hybrid promoters, and in fusion to synthetic poly-histidine (poly-His) sequences for transformation into spring turnip rape (Brassica rapa subsp. oleifera; synonym to B. campestris). The most stable expression cassettes for the poly-His production prior to the plant transformation were selected by analyzing the protein expression in in vitro translation and in transient plant expression systems using GFP as marker. Expression of the poly-His-constructs in transgenic Brassica rapa plants was analyzed using dot and western blotting and PCR. The constructs were stably expressed in the third generation of the transgenic plant lines. Histidine content was measured from the seeds of the transgenic plants, and some plant lines had more than 20% increase in histidine content compared to wild type. The methodology may be widely applicable to increase the content of any amino acid in crop plants including those encoded by rare codons. 相似文献
119.
Ikegaya H Zheng HY Saukko PJ Varesmaa-Korhonen L Hovi T Vesikari T Suganami H Takasaka T Sugimoto C Ohasi Y Kitamura T Yogo Y 《American journal of physical anthropology》2005,128(1):185-193
The JC virus (JCV) genotyping method was used to gain insights into the population history of the Saami and the Finns, both speaking Finno-Ugric languages and living in close geographic proximity. Urine samples from Saami and Finns, collected in northern and southern Finland, respectively, were used to amplify a 610-bp JCV-DNA region containing abundant type-specific mutations. Based on restriction site polymorphisms in the amplified fragments, we classified JCV isolates into one of the three superclusters of JCV, type A, B, or C. All 15 Saami isolates analyzed and 41 of 43 Finnish isolates analyzed were classified as type A, the European type, and two samples from Finns were classified as type B, the African/Asian type. We then amplified and sequenced a 583-bp JCV-DNA region from the type A isolates of Saami and Finns. According to type-determining nucleotides within the region, we classified type A isolates into EU-a1, -a2, or -b. Most type A isolates from Saami were classified as EU-a1, while type A isolates from Finns were distributed among EU-a1, EU-a2, and EU-b. This trend in the JCV-genotype distribution was statistically significant. On a phylogenetic tree based on complete sequences, most of the type A isolates from Saami were clustered in a single clade within EU-a1, while those from Finns were distributed throughout EU-a1, EU-a2, and EU-b. These findings are discussed in the context of the population history of the Saami and the Finns. This study provides new complete JCV DNA sequences derived from populations of anthropological interest. 相似文献
120.
MARCO is the major binding receptor for unopsonized particles and bacteria on human alveolar macrophages 总被引:3,自引:0,他引:3
Arredouani MS Palecanda A Koziel H Huang YC Imrich A Sulahian TH Ning YY Yang Z Pikkarainen T Sankala M Vargas SO Takeya M Tryggvason K Kobzik L 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(9):6058-6064
Alveolar macrophages (AMs) avidly bind and ingest inhaled environmental particles and bacteria. To identify the particle binding receptor(s) on human AMs, we used functional screening of anti-human AM hybridomas and isolated a mAb, PLK-1, which inhibits AM binding of unopsonized particles (e.g., TiO2, latex beads; 63 +/- 5 and 67 +/- 4% inhibition, respectively, measured by flow cytometry; n = 11) and unopsonized bacteria ( approximately 84 and 41% inhibition of Escherichia coli and Staphylococcus aureus binding by mAb PLK-1, respectively). The PLK-1 Ag was identified as the human class A scavenger receptor (SR) MARCO (macrophage receptor with collagenous structure) by observing specific immunolabeling of COS cells transfected with human MARCO (but not SR-AI/II) cDNA and by immunoprecipitation by PLK-1 of a protein of appropriate molecular mass (approximately 70 kDa) from both normal human bronchoalveolar lavage cells (>90% AMs) and human MARCO-transfected COS cells. PLK-1 also specifically inhibited particle binding by COS cells, only after transfection with human MARCO cDNA. Immunostaining showed specific labeling of AMs within human lung tissue, bronchoalveolar lavage samples, as well as macrophages in other sites (e.g., lymph node and liver). Using COS transfectants with different truncated forms of MARCO, allowed epitope mapping for the PLK-1 Ab to MARCO domain V between amino acid residues 420 and 431. A panel of Abs to various SRs identified expression on AMs, but failed to inhibit TiO2 or S. aureus binding. The data support a dominant role for MARCO in the human AM defense against inhaled particles and pathogens. 相似文献