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991.
992.
993.
Louise Pyndt Diederichsen Jesper Nrregaard Michael Krogsgaard Torsten Fischer‐Rasmussen Poul Dyhre‐Poulsen 《Journal of orthopaedic research》2004,22(5):976-983
Morphological studies have demonstrated mechanoreceptors in the capsuloligamentous structures of the shoulder joint, however knowledge of the role these joint receptors play in the control of shoulder stability is limited. We therefore investigated the effect of electrically induced afferent activity from mechanoreceptors in the coracoacromial ligament (CAL) on the activity of voluntary activated shoulder muscles in healthy humans. In study I, wire electrodes, for electrical stimulation, were inserted into the CAL in eight normal shoulders. In study II, a needle electrode was inserted into the CAL in seven normal shoulders. Electric activity was recorded from eight shoulder muscles by surface and intramuscular electrodes. During isometric contractions, electrical stimulation was applied to the CAL at two different stimulus intensities, a weak stimulus (stim-1) and a stronger stimulus (stim-2). In both experiments, electrical stimulation of the CAL elicited a general inhibition in the voluntary activated shoulder muscles. In study I the average latencies (mean+/-SE) of the muscular inhibition were 66+/-4 ms (stim-1) and 62+/-4 ms (stim-2) during isometric flexion and 73+/-3 ms (stim-1) and 73+/-5 ms (stim-2) during isometric extension. In study II the average latency (mean+/-SE) of the response was 66+/-4 ms (stim-1) during isometric flexion. Our results demonstrated a response, probably of reflex origin, from mechanoreceptors in the CAL to the shoulder muscles. The existence of this synaptic connection between mechanoreceptors in CAL and the shoulder muscles suggest a role of these receptors in muscle coordination and in the functional joint stability. 相似文献
994.
Lise Pedersen Susanne Møller Pedersen Claus Lohman Brasen Lars Melholt Rasmussen 《Clinical biochemistry》2013
Objective
Soluble serum Klotho is a new biomarker linked to chronic kidney disease, cardiovascular disease and diabetes. This study describes the evaluation and comparison of two different immunoassays and establishment of assay specific reference intervals in adults.Design and methods
Serum Klotho concentrations were determined in 120 healthy adults aged 19–66 years. Blood samples were collected, and stored sera were assayed for Klotho according to age and gender. In addition several other clinical and laboratory characteristics were determined in the cohort and compared to the levels of serum Klotho.Results
Serum Klotho levels were significantly higher in time-resolved fluorescence immunoassay (TRF) compared to an ELISA (IBL) and no correlation was found between the assays. No signal was obtained in either assay when the standard curve was switched between the two different immunoassays. The median serum Klotho concentration using TRF was 61 ng/mL (2.5–97.5% reference limits; 11–181 ng/mL) for males and 99 ng/mL (2.5–97.5% reference limits; 19–316 ng/mL) for females while the ELISA gave a mean value of 472 pg/mL (2.5–97.5% reference limits; 204–741 pg/mL) with no difference between genders. Concentrations of serum Klotho were independently associated with estimated glomerular filtration rate (eGFR) and body weight using TRF whereas serum Klotho concentrations were associated with age using the ELISA.Conclusion
Comparison of two different immunoassays for serum Klotho indicate, that the protein exists in human beings in different forms which may function as independent factors and whose role and potential value as biomarkers needs to be evaluated separately. Reference intervals specific for the different forms recognized by the different assays were calculated in this study. 相似文献995.
Jeppe Grøndahl Rasmussen Rikke Bülow Eschen Inge Valbak Aardestrup Claus Dethlefsen Bruce A. Griffin Erik Berg Schmidt 《Scandinavian journal of clinical and laboratory investigation》2013,73(1):156-160
Objective. Endothelial dysfunction is a critical, prerequisite step in atherosclerosis, and may be evaluated by flow‐mediated vasodilatation (FMD). The objective of this study was to examine interrelationships between FMD and plasma lipids and lipoproteins, and to determine the between‐operator and within‐subject variability associated with this technique. Material and methods. FMD, plasma lipids and lipoproteins, including small dense LDL (sdLDL), were measured twice in 40 healthy volunteers, 4 weeks apart. Interrelationships between mean FMD responses and plasma lipids and lipoproteins were examined by correlation analysis. FMD measurements were taken by two independent operators, allowing determination of between‐operator variability. Within‐subject variability was determined by obtaining two measurements, 4 weeks apart, in every subject, and carried out by the same operator. Results. FMD was inversely related to plasma triglycerides (r = ?0.47, p = 0.002), total cholesterol/HDL cholesterol (r = ?0.35, p = 0.03) and apolipoprotein B (r = ?0.36, p = 0.02), but not to other plasma lipids and lipoproteins. When measuring variation in FMD, the following results were found: Between operators (SD = 4.0?FMD%) and within subjects (SD = 2.9?FMD%). Conclusions. The associations between FMD, plasma triglycerides and apoB provide evidence supporting a role for triglyceride‐rich lipoproteins in endothelial dysfunction. 相似文献
996.
This study explores the developmental history of ten young men who completed suicide in the transition to adulthood. The young men, aged 18–30, had no previous history of suicide attempts or treatment in mental health. In-depth interviews with four to eight informants for each suicide were analyzed using Interpretative Phenomenological Analysis. Three developmental issues from early age onwards emerged: (a) unsuccessful in becoming independent; (b) weakened competence to deal with shame; and (c) trapped in anger. The capacity to regulate emotions like shame and anger could make certain men vulnerable to suicide when facing adult challenges and defeats. 相似文献
997.
Background: Na+/K+‐ATPase activity is upregulated during muscle exercise to maintain ionic homeostasis. One mechanism may involve movement of α‐subunits to the outer membrane (translocation). Aim: We investigated the existence of exercise‐induced translocation and phosphorylation of phospholemman (PLM, FXYD1) protein in rat skeletal muscle and exercise‐induced changes in Vmax and Km for Na+ of the Na+/K+‐ATPase. Methods: Two membrane fractionation methods and immunoprecipitation were used. Results: Both fractionation methods revealed a 200–350% increase in PLM in the sarcolemma after 30 min of treadmill running, while the phosphorylation of Ser‐68 of PLM appeared to be unchanged. Exercise did not change Vmax or Km for Na+ of the Na+/K+‐ATPase in muscle homogenate, but induced a 67% increase in Vmax in the sarcolemmal giant vesicle preparation; Km for Na+ remained constant. The main part of the increase in Vmax is related to a 36–53% increase in the level of α‐subunits; the remainder may be related to increased PLM content. Similar results were obtained with another membrane purification method. In resting muscle, 29% and 32% of α1‐ and α2‐subunits, respectively, were co‐immunoprecipitated by PLM antibodies. In muscle homogenate prepared after exercise, immunoprecipitation of α1‐subunits was increased to 227%, whereas the fraction of precipitated α2 remained constant. Conclusion: Exercise translocates PLM to the muscle outer membrane and increases its association with mainly the α1‐subunit, which may contribute to the increased Vmax of the Na+/K+‐ATPase. 相似文献
998.
Togsverd M Werge TM Tankó LB Bagger YZ Hansen T Qin G Christiansen C Rasmussen HB 《Journal of affective disorders》2008,106(1-2):169-172
BACKGROUND: Depression has a multifactorial etiology which involves genetic factors and comorbid diseases. METHODS: A cross-sectional sample of 1371 elderly women (mean age=69.2 years) was examined. Detailed information on their health was obtained. Cognitive functions were assessed by the Short Blessed Test and the Animal Naming Task. A 19 bp insertion/deletion polymorphism in the dopamine beta-hydroxylase (DBH) gene, the apolipoprotein (APOE) epsilon2/epsilon3/epsilon4 variation and 5-HTTLPR in the serotonin transporter gene were genotyped. RESULTS: Depression was univariately associated with homozygosity for the DBH gene 19 bp deletion allele (odds ratio [OR]=1.96, 95% confidence intervals [95% CI]=1.17-3.29, p=0.01), family history of depression (OR=3.86, 95% CI=1.85-8.06, p=0.0003), a composite measure of cardiovascular diseases (OR=1.96, 95% CI=1.11-3.47, p=0.02), cognitive impairment assessed by the Short Blessed Test (OR=3.88, 95% CI=1.29-11.64, p=0.02) and performance on the Animal Naming Task (OR=0.74, 95% CI=0.59-0.93, p=0.01). The strength of the association of DBH genotype with depression essentially remained unchanged after correction for other variables in a multivariate model. This association may reflect noradrenaline dysfunction in the brain. 相似文献
999.
1000.
Hemolysin of uropathogenic Escherichia coli evokes extensive shedding of the uroepithelium and hemorrhage in bladder tissue within the first 24 hours after intraurethral inoculation of mice
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Many uropathogenic Escherichia coli (UPEC) strains produce both hemolysin (Hly) and cytotoxic necrotizing factor type 1 (CNF1), and the loci for these toxins are often linked. The conclusion that Hly and CNF1 contribute to urovirulence is supported by the results of epidemiological studies associating the severity of urinary tract infections (UTIs) with toxin production by UPEC isolates. Additionally, we previously reported that mouse bladders and rat prostates infected with UPEC strain CP9 exhibit a more profound inflammatory response than the organs from animals challenged with CP9cnf(1) and that CNF1 decreases the antimicrobial activities of polymorphonuclear leukocytes. More recently, we created an Hly mutant, CP9Delta hlyA(1)::cat, and showed that it was less hemolytic and destructive for cultured bladder cells than CP9 was. Here we evaluated the relative effects of mutations in hlyA(1) or cnf(1) alone or together on the pathogenicity of CP9 in a mouse model of ascending UTI. To do this, we constructed an hlyA(1)-complemented clone of CP9Delta hlyA(1)::cat and an hlyA(1) cnf(1) CP9 double mutant. We found that Hly had no influence on bacterial colonization of the bladder or kidneys in single or mixed infections with the wild type and CP9Delta hlyA(1)::cat but that it did provoke sloughing of the uroepithelium and bladder hemorrhage within the first 24 h after challenge. Finally, we confirmed that CNF1 expression induces bladder inflammation and, in particular, as shown in this study, submucosal edema. From these data, we speculate that Hly and CNF1 may be largely responsible for the signs and symptoms of cystitis in humans infected with toxigenic UPEC. 相似文献