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1 The small protein Bv8, isolated from amphibian skin, belongs to a novel family of secretory proteins (Bv8-Prokineticin family, SWISS-PROT: Q9PW66) whose orthologues have been conserved throughout evolution, from invertebrates to humans. 2 When injected intravenously or subcutaneously (from 0.06 to 500 pmol kg(-1)) or intrathecally (from 6 fmol to 250 pmol) in rats, Bv8 produced an intense systemic nociceptive sensitization to mechanical and thermal stimuli applied to the tail and paws. 3 Topically delivered into one rat paw, 50 fmol of Bv8 decreased by 50% the nociceptive threshold to pressure in the injected paw without affecting the threshold in the contralateral paw. 4 The two G-protein coupled prokineticin receptors, PK-R1 and PK-R2, were expressed in rat dorsal root ganglia (DRG) and in dorsal quadrants of spinal cord (DSC) and bound Bv8 and the mammalian orthologue, EG-VEGF, with high affinity. In DSC, PK-R1 was more abundant than PK-R2, whereas both receptors were equally expressed in DRG. IC(50) of Bv8 and EG-VEGF to inhibit [(125)I]-Bv8 binding to rat DRG and DSC were 4.1+/-0.4 nM Bv8 and 76.4+/-7.6 nM EG-VEGF, in DRG; 7.3+/-0.9 nM Bv8 and 330+/-41 nM EG-VEGF, in DSC. 5 In the small diameter neurons (<30 microm) of rat DRG cultures, Bv8 concentrations, ranging from 0.2 to 10 nM, raised [Ca(2+)](i) in a dose-dependent manner. 6 These data suggest that Bv8, through binding to PK receptors of DSC and primary sensitive neurons, results in intense sensitization of peripheral nociceptors to thermal and mechanical stimuli.  相似文献   
33.
The purpose of this study was to compare the effects of two protocols of electrical stimulation combined with voluntary contractions on the recovery of thigh muscles after anterior cruciate ligament (ACL) surgery. Ten sportsmen with a mean age of 26 yrs were randomly assigned into two groups: a 80 Hz stimulated group (5 patients) and a 20 Hz stimulated group (5 patients). All patients received electrical stimulation of the quadriceps femoris, five days a week, for 12 weeks, and had a standard program of voluntary contractions. Muscle and fat volumes of the thigh were assessed using MRI before surgery and after 12 weeks of rehabilitation. Quadriceps and hamstring muscle strength were evaluated by isokinetic measurements. Twelve weeks after surgery, the quadriceps peak torque deficit in the operated limb with respect to the non operated limb at 180 degrees /s and 240 degrees /s was significantly (p < 0.05) less in the 20 Hz group than in the 80 Hz group. This difference was not confirmed when comparing the pre-surgery quadriceps peak torque of the operated limb with the post-surgery one. Subcutaneous fat volume was increased for the two groups at the post-surgery test. This increase was significantly (p < 0.05) greater for the 80 Hz group. Thigh muscle volume deficit was not significantly different between the two groups.  相似文献   
34.
Serum and salivary IgA and IgG antigliadin antibodies were determined by an enzyme-linked immunosorbent assay in 18 children with villous atrophy and 30 children on a gluten-free diet for coeliac disease in whom normal intestinal mucosa was found. Serum IgA anti-endomysium antibodies were also determined by an immunofluorescence method in these children. Serum IgG antigliadin and IgA anti-endomysium antibodies had the highest sensitivity (100 and 94.4%, respectively), followed by serum IgA antibodies to gliadin (72.2%), salivary IgA antigliadin (61.2%) and IgG antigliadin (50%) antibodies. The highest specificity was found for serum IgA anti-endomysium (100%) and IgA antigliadin (96.6%) antibodies and salivary IgA and IgG antigliadin antibodies (93.3%), while serum IgG antigliadin antibodies were found to be least specific (63.3%)  相似文献   
35.
The clinical records of 207 patients with squamous cell carcinoma of the head and neck, diagnosed and surgically treated at the Otolaryngology Division of Pordenone General Hospital and Aviano Cancer Centre, northeast of Italy, from January 1982 to December 1987, were retrospectively reviewed to gather information on blood transfusions and other characteristics potentially related to survival. The group of patients (mean age = 59 years) included 85 cases (41%) of laryngeal cancer, 80 cases (39%) of oropharyngeal and hypopharyngeal cancer, and 34 cases (16%) of cancer of the oral cavity. Fifty-five patients (27%) did not receive any blood transfusion while 152 patients were transfused with different amounts of blood. At the univariate analysis, nodal involvement, clinical stage, type of therapy, status of surgical margins, and metastatic spread beyond the nodal capsule appeared to be significantly linked to prognosis. After adjustment for other prognostic variables, transfused patients showed a twofold higher hazard ratio as compared to nontransfused patients, but such an unfavorable predictive value should be evaluated in the context of the other prognostic correlates of cancer of the head and neck.  相似文献   
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Because of the importance of surface waters from the Chillán River watershed (Chile) for recreation, agricultural irrigation, and the production of drinking water, local concern about river water quality has increased considerably during the last decade. Agricultural and forestry activities in the watershed, characterized by an intensive use of pesticides, are thought to play an important role in the generation of non-point-source pollution, whereas the discharge of urban wastewater from the city of Chillán constitutes a major point source of pollution. In the present investigation, acute and chronic laboratory bioassays using Daphnia spp. were conducted on surface water samples from 17 river stations located throughout the watershed. Sampling occurred on 6 occasions during a 16-month period (2000 to 2001) and included both high and low flow conditions. Almost all toxic effects observed in summer were directly related to the discharge of urban wastewater, whereas toxicity in rural areas was mainly detected during the winter period when rainfall and river flow are high. Toxicity test results were compared with measured physicochemical water-quality data. Mortality and alterations in reproductive success of Daphnia spp. were not consistently reflected in detected chemical pollution. With only one exception (atrazine), detected pesticide concentrations were below known toxicity levels. However, additive and synergistic effects of the presence of a mixture of pesticides could not be excluded as a possible cause of observed toxicity. At several stations, filtering of the water sample led to a strong decrease in toxicity, which suggests the presence of xenobiotics attached to the smaller sediment fraction. Inclusion of sediment chemical analysis and sediment toxicity testing in future work should therefore be encouraged. The presented approach provided information about the adverse effects of human activities on surface water quality in the watershed, not easily obtained from classical monitoring schemes. In specific cases, the approach may represent an economically attractive alternative to physicochemical analyses. Modifications to the proposed methodology should be introduced if the effects of intrastorm and interstorm variability of water quality are to be analyzed.  相似文献   
38.
Four pulp and paper mills discharge their effluents in the same section of the Biobio River in central southern Chile. Pulp mill effluents are a very complex mixture with characteristics that depend on the type of raw material, the process technology, and the effluent treatment. To investigate the effect of pulp mill effluent discharges, immature Oncorhynchus mykiss were exposed to river sediments in the laboratory for 29 d. Three sampling areas were defined in a spatial gradient in the river: Preimpact, impact, and postimpact zones relative to the pulp and paper mill discharge areas. Ethoxyresorufin-O-deethylase activities were significantly higher in fish exposed to impact and postimpact sediments when compared to those exposed to preimpact sediments, and higher levels of vitellogenin were observed in the plasma of female fish exposed to impact and postimpact sediments. Histological analysis of the gonadal tissue showed an induction of gonadal maturation in fish exposed to sediment coming from the impact and postimpact zones (oocytes in a vitellogenic state). No site differences were observed in erythrocytes, although differences were noted in the leukocytes in the exposure areas. Finally, the biomarker approach showed evidence that the sediment associated with pulp mill effluent discharges produces some effects in fish under laboratory conditions.  相似文献   
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Analysis of H-2 class I-specific cDNA clones has suggested the synthesis by the liver of a class I molecule that is secreted rather than membrane bound. To detect this putative class I-related molecule, we have predicted a unique region of amino acid sequence located toward the carboxyl terminus of the molecule that is not expected to be shared with any of the classical H-2 class I antigens, and we have generated specific antibodies to a synthetic peptide corresponding to this sequence. Indirect immunoprecipitation with this antibody led to the identification of a Mr 40,000 polypeptide in association with beta 2-microglobulin in the serum of mice of five different H-2 haplotypes. This class I molecule is also detected in the liver together with lower molecular weight components, which are presumably underglycosylated precursors. Synthesis of this molecule is not detected in thymus, spleen, kidney, or testis. This class I serum component has no detectable reactivity with either a broad-specificity alloantiserum against H-2b or a xenoantiserum against purified H-2a class I molecules. The availability of a specific antibody against the secreted class I molecule offers a means to purify this protein for structural and functional studies.  相似文献   
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