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Chemical, i.e. cuticular hydrocarbons, and molecular data were used to probe the phylogeography of Reticulitermes termites collected from various parts of France, Spain and Portugal. Phylogenetic relationships were inferred from sequences of the internal transcribed spacer (ITS2) of nuclear ribosomal RNA genes as well as from two partial mitochondrial DNA segments, the cytochrome oxidase II gene and a sequence combining the tRNA-Leu gene and fragments of the NADH dehydrogenase I and ribosomal 16S genes. Two species, namely, R. grassei and R. banyulensis, were identified based on an analysis of cuticular hydrocarbons and the identification was confirmed by ITS2 haplotyping. However, phylogeny based on the analysis of mitochondrial DNA was not completely in agreement with the conclusions drawn from the chemical and nuclear data. An analysis of 56 R. grassei colonies revealed intraspecific differentiation into two major lineages with distinct geographical ranges. Whereas analysis of cuticular hydrocarbons showed that R. banyulensis was chemically distinct from R. grassei, analysis of mitochondrial DNA showed its close kinship with the R. grassei lineage occurring in southern Spain. This kinship could be explained by their evolution from a common polymorphic ancestor species in this ice age refugium.  相似文献   
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The Holoarctic termite genus Reticulitermes is widely distributed in Europe. A new Reticulitermes species, R. sp. nov, was recently found in France and Italy. Its phylogenetic position was investigated using a 743-bp fragment of mitochondrial 16S rRNA-ND1 genes and 382-bp of the nuclear ITS2 region. Phylogenies for these sequences were estimated by neighbor-joining, maximum-parsimony and maximum-likelihood analysis. The results strongly supported a relationship between R. sp. nov. and the termite species from the eastern Mediterranean area including Reticulitermes balkanensis from the Balkans, Reticulitermes lucifugus from Turkey and Reticulitermes clypeatus from Israel. The hypothesis of a relationship between R. sp. nov. and the Japanese Reticulitermes speratus was rejected by parametric bootstrap. The current distribution of R. sp. nov. could be linked to postglacial colonization routes between Balkan refuge and northern regions.  相似文献   
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Introduction  

Rheumatoid arthritis (RA) frequently involves the loss of tolerance to citrullinated antigens, which may play a role in pathogenicity. Citrullinated fibrinogen is commonly found in inflamed synovial tissue and is a frequent target of autoantibodies in RA patients. To obtain insight into the B-cell response to citrullinated fibrinogen in RA, its autoepitopes were systematically mapped using a new methodology.  相似文献   
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A galanin (GAL)-like peptidergic system was investigated in the brain of Anguilla anguilla subjected to hyperosmolar and hypoosmolar conditions, by using antisera raised against porcine 1-29 GAL. A group of immunoreactive perikaria was identified in the periventricular hypothalamus, in the ventral thalamus, in the pretectal areas and in the optic tectum. Immunoreactive perikaria were present in the nucleus lateralis of the torus semicircularis in seawater (SW) adapted eels, and were absent in the freshwater (FW) adapted eels. Galaninergic fibres were observed in many areas of the brain. The immunoreactive perikaria and fibres, when localised in the same areas, were more strongly labelled and numerous in the SW adapted eels in comparison to the FW adapted animals. GAL-specific binding sites, investigated by autoradiography using iodinated porcine GAL, occurred in several regions of the brain, in particular in the dorsal telencephalon, in the dorsal thalamus and in the torus semicircularis, where a high density of binding sites was observed in the SW adapted eels. Conversely, a higher density of binding sites was observed in the caudal substantia reticularis and in the corpus cerebelli in the FW adapted eels. We conclude that different distributions and intensity in immunoreactive elements occur in response to the two environmental conditions.  相似文献   
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Background

Due partly to physicians’ unawareness, many adults with Pompe disease are diagnosed with great delay. Besides, it is not well known which factors influence the rate of disease progression, and thus disease outcome. We delineated the specific clinical features of Pompe disease in adults, and mapped out the distribution and severity of muscle weakness, and the sequence of involvement of the individual muscle groups. Furthermore, we defined the natural disease course and identified prognostic factors for disease progression.

Methods

We conducted a single-center, prospective, observational study. Muscle strength (manual muscle testing, and hand-held dynamometry), muscle function (quick motor function test), and pulmonary function (forced vital capacity in sitting and supine positions) were assessed every 3–6 months and analyzed using repeated-measures ANOVA.

Results

Between October 2004 and August 2009, 94 patients aged between 25 and 75 years were included in the study. Although skeletal muscle weakness was typically distributed in a limb-girdle pattern, many patients had unfamiliar features such as ptosis (23%), bulbar weakness (28%), and scapular winging (33%). During follow-up (average 1.6 years, range 0.5-4.2 years), skeletal muscle strength deteriorated significantly (mean declines of ?1.3% point/year for manual muscle testing and of ?2.6% points/year for hand-held dynamometry; both p<0.001). Longer disease duration (>15 years) and pulmonary involvement (forced vital capacity in sitting position <80%) at study entry predicted faster decline. On average, forced vital capacity in supine position deteriorated by 1.3% points per year (p=0.02). Decline in pulmonary function was consistent across subgroups. Ten percent of patients declined unexpectedly fast.

Conclusions

Recognizing patterns of common and less familiar characteristics in adults with Pompe disease facilitates timely diagnosis. Longer disease duration and reduced pulmonary function stand out as predictors of rapid disease progression, and aid in deciding whether to initiate enzyme replacement therapy, or when.
  相似文献   
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A novel and efficient tagArray technology was developed that allows rapid identification of antibodies which bind to receptors with a specific expression profile, in the absence of biological information. This method is based on the cloning of a specific, short nucleotide sequence (tag) in the phagemid coding for each phage-displayed antibody fragment (phage-Ab) present in a library. In order to set up and validate the method we identified about 10,000 different phage-Abs binding to receptors expressed in their native form on the cell surface (10 k Membranome collection) and tagged each individual phage-Ab. The frequency of each phage-Ab in a given population can at this point be inferred by measuring the frequency of its associated tag sequence through standard DNA hybridization methods. Using tiny amounts of biological samples we identified phage-Abs binding to receptors preferentially expressed on primary tumor cells rather than on cells obtained from matched normal tissues. These antibodies inhibited cell proliferation in vitro and tumor development in vivo, thus representing therapeutic lead candidates.  相似文献   
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Na+-K+-Cl- cotransport and Na+/K+ATPase were studied by immunohistochemistry in the kidney and urinary bladder of Trematomus bernacchii and Chionodraco hamatus. The activity was correlated to the density of mitochondria. The first segment of the renal proximal tubule was more active than the second one. In T. bernacchii and the temperate marine teleost Pagellus bogaraveo, the immunoreactivity for the antibody to cotransporters and to the !-subunit of the sodium pump was stronger than in the icefish. This difference indicates in the kidney of the icefish, a weaker secretory activity, a consequent lower osmolarity in the lumen and lower water loss, which correlates well with the need for a greater blood volume in the icefish. The epithelium of the urinary bladder in T. bernacchii, where intense immunostaining was observed, was composed of columnar cells. In C. hamatus the columnar cells, where the immunostaining was weaker, lined only a portion of the urinary bladder, the other region being composed of cuboidal cells.  相似文献   
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