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61.
Anders Lundqvist Adiba Isa Thomas Tolfvenstam G?ran Kvist Kristina Broliden 《Journal of clinical virology》2005,33(1):71-74
BACKGROUND: Human parvovirus B19 (B19) polymerase chain reaction (PCR) is now a routine analysis and serves as a diagnostic marker as well as a complement or alternative to B19 serology. The clinical significance of a positive B19 DNA finding is however dependent on the type of tissue or body fluid analysed and of the immune status of the patient. OBJECTIVES: To analyse the clinical significance of B19 DNA positivity in bone marrow samples from rheumatic patients. STUDY DESIGN: Parvovirus B19 DNA was analysed in paired bone marrow and serum samples by nested PCR technique. Serum was also analysed for B19-specific IgG and IgM antibodies and the results were compared with clinical and epidemiological data. RESULTS AND CONCLUSIONS: B19 IgG was found in 41 of 50 patients (82%) whereas none was B19 IgM positive. The serologic evaluation showed that none of the patients had acute B19 infection. However, B19 DNA was detected by PCR in 13 of 50 (26%) bone marrow samples from these patients indicating a high frequency of persistent infection compared with previous reports of patient groups and healthy controls. In the study, 22 patients had rheumatoid arthritis (RA) and 7 of these RA patients were B19 DNA positive in bone marrow. Rheumatoid factor was positive in 4 of the 7 B19 DNA positive RA patients as compared with Rheumatoid factor positivity in all of the 15 B19 DNA negative RA patients. Erosive arthritis in X-ray was less common in the B19 DNA positive group than in the B19 DNA negative group. A high frequency of parvovirus B19 DNA was thus detected in bone marrow samples in rheumatic patients. The clinical data does not support a direct association between B19 PCR positivity and rheumatic disease manifestation. Therefore, the clinical significance of B19 DNA positivity in bone marrow samples from rheumatic patients must be interpreted with caution. 相似文献
62.
Grasp stability during object manipulation is achieved by the grip forces applied normal to the grasped surfaces increasing and decreasing in phase with increases and decreases of destabilizing load forces applied tangential to the grasped surfaces. This force coordination requires that the CNS anticipates the grip forces that match the requirements imposed by the self-generated load forces. Here, we use functional MRI (fMRI) to study neural correlates of the grip-load force coordination in a grip-load force task in which six healthy humans attempted to lift an immovable test object held between the tips of the right index finger and thumb. The recorded brain activity was compared with the brain activity obtained in two control tasks in which the same pair of digits generated forces with similar time courses and magnitudes; i.e., a grip force task where the subjects only pinched the object and did not apply load forces, and a load force task, in which the subjects applied vertical forces to the object without generating grip forces. Thus neither the load force task nor the grip force task involved coordinated grip-load forces, but together they involved the same grip force and load force output. We found that the grip-load force task was specifically associated with activation of a section of the right intraparietal cortex, which is the first evidence for involvement of the posterior parietal cortex in the sensorimotor control of coordinated grip and load forces in manipulation. We suggest that this area might represents a node in the network of cortical and subcortical regions that implement anticipatory control of fingertip forces for grasp stability. 相似文献
63.
Terje Espevik Mark Otterlei Gudmund Skjk-Braek Liv Ryan Samuel D. Wright Anders Sundan 《European journal of immunology》1993,23(1):255-261
In this study the molecular mechanisms behind the stimulatory activities of the uronic acid polymers poly mannuronic acid (poly M), high M alginate and oxidized cellulose (C60XY) were investigated and compared with lipopolysaccharide (LPS). The cytokine-inducing abilities of the uronic acid polymers and LPS were examined on CD14-positive human monocytes and CD14-negative U373 astrocytoma cells. It was found that LPS induced monocytes and U373 cells to produce tumor necrosis factor (TNF) and interleukin(IL)-6, respectively, by different mechanisms. The poly uronic acids induced monocytes to produce TNF, but with 100-1000 times less potency compared to LPS. On U373 cells, LPS at concentrations ? 32 ng/ml resulted in a dose-related IL-6 production, whereas the poly uronic acids had negligible effects even at 1 mg/ml. The binding data demonstrate that only the CD14-positive monocytes in the peripheral blood mononuclear cells population bound poly M. Furthermore, poly M was found to bind to CD14 in the presence of serum. Antibodies against CD14 also inhibited the TNF-inducing activity of the three uronic acid polymers tested. In conclusion, these results demonstrate that uronic acid polymers induce TNF production through mechanisms which involve CD 14. 相似文献
64.
Sana Eltayeb Anna-Lena Berg Hans Lassmann Erik Wallström Maria Nilsson Tomas Olsson Anders Ericsson-Dahlstrand Dan Sunnemark 《Journal of neuroinflammation》2007,4(1):14-13
Background
The CC chemokine receptors CCR1, CCR2 and CCR5 are critical for the recruitment of mononuclear phagocytes to the central nervous system (CNS) in multiple sclerosis (MS) and other neuroinflammatory diseases. Mononuclear phagocytes are effector cells capable of phagocytosing myelin and damaging axons. In this study, we characterize the regional, temporal and cellular expression of CCR1, CCR2 and CCR5 mRNA in the spinal cord of rats with myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis (MOG-EAE). While resembling human MS, this animal model allows unique access to CNS-tissue from various time-points of relapsing neuroinflammation and from various lesional stages: early active, late active, and inactive completely demyelinated lesions. 相似文献65.
66.
67.
C-reactive protein (CRP) was assessed in pediatric serum samples using different commercial latex reagents, which were analyzed for species origin of the coating antibodies, homogeneity and density of the latex particles, and prozone agglutinating capacity. All reagents correctly agglutinated the positive and negative control sera. The antibodies coating the particles differed with regard to species origin: one was coated with rabbit, one with horse and goat, one with horse, goat, rabbit and swine, while the reference reagent had horse, goat and rabbit antibodies.Only the monospecies specific antibody-coated latex showed obvious prozoning; this reagent also had the smallest and most homogenous latex particles and showed the most clear-cut reactions. False agglutination was observed at 7–26% according to quantitation with the spot immunoprecipitate assay, which compared favorably with radial immunodiffusion measurements. The lowest percentage of false readings was noted for the rabbit antibody-coated particles; the highest for the reagent with particles coated using antibodies from 4 different species.No reagent had satisfactory precision for the low positive sera between 10 and 40 mg CRP/1. 相似文献
68.
Anders Pettersson Kathryn Gradin Thomas Hedner Bengt Persson 《Naunyn-Schmiedeberg's archives of pharmacology》1985,329(4):394-397
Summary Ketanserin is a new antihypertensive agent with affinity to serotonin (5-HT)2 receptors and at higher concentrations also to
1-adrenoceptors. The present study was designed to evaluate the relative functional importance of the antagonism of
1-adrenoreceptors and 5-HT2-receptors in the antihypertensive mechanism of action of ketanserin and analogues after acute administration. In the spontaneously hypertensive rat, ketanserin and the two ketanserin analogues, R56413 and R55667 (which have relatively weaker -adrenolytic properties) were studied with regard to their ability to reduce the blood pressure after acute administration in the conscious rat and their ability to shift the dose response curves for 5-HT and phenylephrine in the pithed rat. The agents tested reduced the blood pressure only in a dose range where they blocked
1-adrenoceptors and there was a striking correlation between the degree of hypotension and the degree of inhibition of the phenylephrine induced pressor responses. 5-HT2-receptor blockade alone did not influence basal blood pressure. However, following pretreatment with R55667 in a low dose the blood pressure reduction to prazosin was enhanced.It is concluded that following acute administration in the rat the major portion of the antihypertensive response to ketanserin is due to an
1-adrenoceptor blockade but that the 5-HT2-receptor blockade contributes.Abbreviations 5-HT
5-hydroxytryptamine
- SHR
spontaneously hypertensive rat
- SNS
sympathetic nervous stimulation 相似文献
69.
Anders B. Fischer M.D. 《World journal of surgery》1984,8(3):293-302
One thousand twenty-five patients underwent a Billroth II resection for duodenal ulcer between 1948 and 1956. The operative mortality rate was 2.4%. At follow-up between 22 and 30 years later, 522 had died and 423 patients were traced. Recurrent ulcer appeared in 2.6% of the cases. Postgastrectomy symptoms occurred with the following frequency: dumping 10%, diarrhea 5%, vomiting 7%, and pain 4%. Anemia developed in 18%, hypoalbuminemia and hypocalcemia in 40 and 15%, respectively. Eleven percent had lost more than 10 kg in weight. Tuberculosis was found in 3% of the cases. While 90% of the patients were satisfied with the result, 10% were failures. The overall mortality rate was significantly increased because of suicide. Gastric carcinoma was the cause of death no more often than expected.
Supported by grants from the Danish Medical Research Council (No. 512-8760) and Købmand i Odense Johann & Hanne Weimann, født Seedorffs legat. 相似文献
Resumen En años anteriores la gastrectomía Billroth II fue un procedimiento operatorio de uso común en el tratamiento de la úlcera duodenal. Los promisorios resultados de la vagotomía con drenaje, vagotomía y antrectomía y, especialmente, la vagotomía de células parietales han reducido el rol de la resección de tipo Bilroth II. El propósito del presente estudio es describir los resultados a largo plazo en un grupo de pacientes sometidos a gastrectomía Billroth II por úlcera duodenal aproximadamente 25 años antes.Entre 1948 y 1956, 1 025 pacientes consecutivos, 810 hombres y 190 mujeres, fueron sometidos a resección Billroth II por úlcera duodenal. La mortalidad operatoria fué de 2,4%. Durante el período de seguimiento entre 22 y 30 años, 522 pacientes habían muerto y 423 pacientes pudieron ser ubicados para seguimiento. Síntomas de post-gastrectomía fueron observados con la incidencia siguiente: dumping 10%, diarrea 5%, vómito 7% y dolor 4%. La anemia se presentó en el 18%, hipoalbuminemia e hipocalcemia en el 40% y en el 15% respectivamente. Se presentó tuberculosis en el 3% de los casos. El 90% de los pacientes se mostraron satisfechos con el resultado de la operación, pero el 10% restante indicó la falla del tratamiento. La mortalidad global resultó significativamente incrementada debido a una alta incidencia de suicidio. El carcinoma gástrico fue causa de muerte con una frecuencia no aumentada, o sea que no se encontró un mayor riesgo de muerte por carcinoma de esófago o del remanente gástrico.
Résumé De 1948 à 1956, 1 025 malades atteints d'ulcère duodénal ont subi une opération de Billroth II. La mortalité a été de 2,4%. Au cours de l'évolution de 22 à 30 ans après l'intervention, 522 opérés sont décédés et 423 ont été suivis. La fréquence de la récidive a été de 2,6%. Les symptômes après gastrectomie ont atteint les taux suivants: dumping 10%, diarrhée 5%, vomissements 7%, douleur 4%. L'anémie a été constatée dans 18% des cas, l'hypoalbuminémie dans 40% des cas et l'hypocalcémie dans 15% des cas, onze pour cent des opérés ont accusé une chute pondérale supérieure à 10 kg; 3% ont présenté une tuberculose. Au total 90% des malades se sont déclarés satisfaits de l'intervention, encore que certains opérés se soient suicidés, ce nombre intervenant dans la mortalité globale. La mortalité par cancer n'a pas dépassé le taux accusé par la population en général.
Supported by grants from the Danish Medical Research Council (No. 512-8760) and Købmand i Odense Johann & Hanne Weimann, født Seedorffs legat. 相似文献
70.
A low intake of selenium is associated with increased cardiovascular mortality. This could be reduced by supplementation with selenium and coenzyme Q10. D-dimer, a fragment of fibrin mirroring fibrinolysis, is a biomarker of thromboembolism, increased inflammation, endothelial dysfunction and is associated with cardiovascular mortality in ischemic heart disease. The objective was to examine the impact of selenium and coenzyme Q10 on the level of D-dimer, and its relationship to cardiovascular mortality. D-dimer was measured in 213 individuals at the start and after 48 months of a randomised double-blind placebo-controlled trial with selenium yeast (200 µg/day) and coenzyme Q10 (200 mg/day) (n = 106) or placebo (n = 107). The follow-up time was 4.9 years. All included individuals were low in selenium (mean 67 μg/L, SD 16.8). The differences in D-dimer concentration were evaluated by the use of T-tests, repeated measures of variance and ANCOVA analyses. At the end, a significantly lower D-dimer concentration was observed in the active treatment group in comparison with those on placebo (p = 0.006). Although D-dimer values at baseline were weakly associated with high-sensitive CRP, while being more strongly associated with soluble tumour necrosis factor receptor 1 and sP-selectin, controlling for these in the analysis there was an independent effect on D-dimer. In participants with a D-dimer level above median at baseline, the supplementation resulted in significantly lower cardiovascular mortality compared to those on placebo (p = 0.014). All results were validated with a persisting significant difference between the two groups. Therefore, supplementation with selenium and coenzyme Q10 in a group of elderly low in selenium and coenzyme Q10 prevented an increase in D-dimer and reduced the risk of cardiovascular mortality in comparison with the placebo group. The obtained results also illustrate important associations between inflammation, endothelial function and cardiovascular risk. 相似文献