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991.
992.
The aim of this study was to investigate the expression of thrombospondin-1 (TSP-1) and its receptors, lipoprotein receptor-related protein/cluster of differentiation (CD)91, calreticulin (CRT), and CD47, on T cells and monocytes from patients with rheumatoid arthritis (RA) treated with anti-tumor necrosis factor (TNF) therapy. The surface expression of CD91 and associated components on CD3- and CD14-positive cells was examined using flow cytometry in 12 patients with established RA before and after beginning therapy and compared with that of 9 healthy controls and 12 patients with early RA treated with conventional therapies. CD3-positive cells from anti-TNF non-responders showed significantly greater expression of CD91 expression than those from responders (p<0.05) after 6 weeks and when all measurements were pooled (p<0.001). CD91 expression on CD3-positive cells from non-responders to other therapies was at the same level as in healthy controls. In contrast, CD14-positive cells showed no differences in CD91 expression between patients and controls or between responders and non-responders to anti-TNF therapy. The expression of TSP-1, CRT, and CD47 showed no differences between responders and non-responders. The results suggest T-lymphocyte expression of CD91 to be a biomarker that signifies unresponsiveness to anti-TNF therapy in patients with RA and may be used to identify potential responders and non-responders.  相似文献   
993.
This study presents evidence that human platelets bind lipopolysaccharide (LPS) from enterohemorrhagic Escherichia coli (EHEC) through a complex of toll-like receptor 4 (TLR4) and CD62, leading to their activation. TLR4 colocalized with CD62 on the platelet membrane, and the TLR4 specificity of LPS binding to platelets was confirmed using C57BL/10ScN mice lacking Tlr4. Only platelets from TLR4 wild-type mice bound O157LPS in vitro. After in vivo injection, O157LPS bound to platelets from wild-type mice, which had lower platelet counts than did mice lacking TLR4. Mouse experiments confirmed that O157LPS binding to TLR4 is the primary event leading to platelet activation, as shown by CD40L expression, and that CD62 further contributes to this process. Activation of human platelets by EHEC-LPS was demonstrated by expression of the activated GPIIb/IIIa receptor, CD40L, and fibrinogen binding. In perfusion experiments, platelet activation on endothelial cells was TLR4 and CD62 dependent. O157LPS was detected on platelets from 12 of 14 children with EHEC-associated hemolytic uremic syndrome (HUS) and on platelets from 2 children before the development of HUS but not on platelets of EHEC-infected children in whom HUS did not develop (n = 3). These data suggest that O157LPS on platelets might contribute to platelet consumption in HUS.  相似文献   
994.
The aim of this study was to examine a possible role for extracellular pyrimidines as inotropic factors for the heart. First, nucleotide plasma levels were measured to evaluate whether UTP is released in patients with coronary heart disease. Then, inotropic effects of pyrimidines were examined in isolated mouse cardiomyocytes. Finally, expression of pyrimidine-selective receptors (a subgroup of the P2 receptors) was studied in human and mouse heart, using real time polymerase chain reaction, Western blot, and immunohistochemistry. Venous plasma levels of UTP were increased (57%) in patients with myocardial infarction. In electrically stimulated cardiomyocytes the stable P2Y(2/4) agonist UTPgammaS increased contraction by 52%, similar to beta1-adrenergic stimulation with isoproterenol (65%). The P2Y6-agonist UDPbetaS also increased cardiomyocyte contraction (35%), an effect abolished by the P2Y6-blocker MRS2578. The phospholipase C inhibitor U73122 inhibited both the UDPbetaS and the UTPgammaS-induced inotropic effect, indicating an IP3-mediated effect via P2Y6 receptors. The P2Y14 agonist UDP-glucose was without effect. Quantification of mRNA with real time polymerase chain reaction revealed P2Y2 as the most abundant pyrimidine receptor expressed in cardiomyocytes from man. Presence of P2Y6 receptor mRNA was detected in both species and confirmed at protein level with Western blot and immunohistochemistry in man. In conclusion, UTP levels are increased in humans during myocardial infarction, giving the first evidence for UTP release in man. UTP is a cardiac inotropic factor most likely by activation of P2Y2 receptors in man. For the first time we demonstrate inotropic effects of UDP, mediated by P2Y6 receptors via an IP3-dependent pathway. Thus, the extracellular pyrimidines (UTP and UDP) could be important inotropic factors involved in the development of cardiac disease.  相似文献   
995.
A limited number of clinical studies have examined the effect of poststroke rehabilitation with robotic devices on hemiparetic arm function. We systematically reviewed the literature to assess the effect of robot-aided therapy on stroke patients' upper-limb motor control and functional abilities. Eight clinical trials were identified and reviewed. For four of these studies, we also pooled short-term mean changes in Fugl-Meyer scores before and after robot-aided therapy. We found that robot-aided therapy of the proximal upper limb improves short- and long-term motor control of the paretic shoulder and elbow in subacute and chronic patients; however, we found no consistent influence on functional abilities. In addition, robot-aided therapy appears to improve motor control more than conventional therapy.  相似文献   
996.
Leptin is a pleiotrophic protein mainly produced by adipocytes that has been implicated as a link between nutritional status and immune function. Severe bacterial infection is associated with elevated plasma levels of leptin. To determine the role of leptin in the host response to bacterial pneumonia leptin deficient ob/ob mice and normal wild-type (WT) mice were intranasally infected with different doses of the Gram-positive pathogen Streptococcus (S.) pneumoniae or the Gram-negative bacterium Klebsiella (K.) pneumoniae. After infection with lower doses of either pathogen ob/ob mice displayed lower pulmonary levels of proinflammatory cytokines, in particular tumor necrosis factor-alpha and chemokines. However, after infection with a higher dose of S. pneumoniae or K. pneumoniae the lung concentrations of these inflammatory mediators did not differ between ob/ob and WT mice. In addition, the extent and severity of lung inflammation, as assessed by semi-quantitative histopathology scores, were similar in both mouse strains. Finally, leptin deficiency did not impact on the bacterial outgrowth in the lungs during either Gram-positive or Gram-negative pneumonia irrespective of the infective dose. These data suggest that although leptin may play a modest role in the regulation of inflammation during bacterial pneumonia, it does not contribute to host defense mechanisms that act to limit the outgrowth of S. pneumoniae or K. pneumoniae in the lower airways.  相似文献   
997.
Mycobacterium kansasii has emerged as an important nontuberculous mycobacterium that can cause severe infection in the immunocompromised host, especially in human immunodeficiency virus-infected patients. However, little is known about the pathogenesis of this infection. Because patients suffering from M. kansasii infection are severely compromised in their cellular immune response, we studied the course of infection in CD4+ cell knockout (KO) mice. Wild-type (WT) mice and CD4+ KO mice were infected with 10(5) cfu of M. kansasii. Although previously shown to be susceptible to Mycobacterium tuberculosis infection, CD4+ KO mice demonstrated no impairment in clearing infection with M. kansasii when compared with WT animals, despite reduced pulmonary inflammation (reduced granuloma formation and lymphocyte infiltration in the lungs). Pulmonary IFN-gamma levels and M. kansasii-induced IFN-gamma production by splenocytes from infected animals were reduced in CD4+ KO mice, confirming that these mice were defective in the M. kansasii-specific T helper cell type 1 immune response. Furthermore, mice deficient for IFN-gamma, IL-12p35, IL-12p40, or IL-18 also displayed a normal host defense against pulmonary infection with M. kansasii. These data suggest that CD4+ cells, IFN-gamma, and an intact T helper cell type 1 response play a limited role in protective immunity against pulmonary M. kansasii infection.  相似文献   
998.
Hyperparathyroidism-jaw tumor syndrome (HPT-JT) is an important diagnosis because of the possible involvement of other family members and risk of malignant disease. We report clinical and genetic studies in a previously undocumented Australian family with HPT-JT. The proband and his sister presented with bilateral or recurrent mandibular radiolucencies diagnosed histopathologically as cemento-ossifying fibromas. Mutation screening of the recently identified disease gene HRPT2 was performed by direct sequencing in 3 affected members. This revealed a novel mutation in exon 1 of HRPT2 (nt 20AGGACG --> GGGAG), which is predicted to inactivate the parafibromin protein through protein truncation and premature termination of translation. The terminology used for the jaw lesions in this syndrome warrants review to become more consistent. Cemento-ossifying fibroma is the preferred term to better reflect the pathologies found in most individuals and families,and to emphasize the significance of the jaw lesions in the diagnosis of the syndrome.  相似文献   
999.
OBJECTIVE: To compare the performance of the Disabilities of the Arm, Shoulder and Hand Outcome (DASH) Questionnaire and the Moberg Picking Up Test (MPUT) with other outcome measurement tools in assessing both hand function and aspects of general health in finger joint arthroplasty in patients with rheumatoid arthritis (RA). DESIGN: Case series, with an average follow-up duration of 104.9 months. SETTING: Orthopedic outpatient clinic at a university hospital. PARTICIPANTS: Of 64 consecutive patients (21 dead, 6 lost to follow-up), 37 patients with 140 spacers in 107 metacarpophalangeal and 33 proximal interphalangeal joints of 51 hands were evaluated. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Hand function tests and general health measures. RESULTS: The DASH correlated with both hand function (Health Assessment Questionnaire: r=.72, P<.01; MPUT: r=0.6, P<.01) and general health (Medical Outcomes Study 36-Item Short-Form Health Survey subscales: r range, -.73 to -.31; P range, <.001 to <.05). The MPUT was a suitable tool for precision grip testing. CONCLUSIONS: The DASH has the advantage of being self-administered and assesses both functional and health aspects. It can be recommended as an instrument for a routine clinical follow-up for patients with hand surgery and RA. Additional tests should be applied when detailed information is needed.  相似文献   
1000.

Ethnopharmacological relevance

Pterodon pubescens Benth is a medicinal plant commonly used for therapeutic purposes in folk medicine for rheumatic diseases' treatment. In the present work we analyzed the chemical composition of the oleaginous extract of P. pubescens Benth (OEPp) and extended the antinociceptive effect of OEPp evaluating its role on animal models of acute and chronic pain.

Materials and methods

The antinociceptive and antiedematogenic effects of OEPp (3–100 mg/kg, i.g.) were evaluated in the formalin test; mechanical allodynia in the postoperative pain and complex regional pain syndrome type-I (CRPS-I) animal models; and thermal hyperalgesia was induced by plantar incision. Finally, we performed a phytochemical analysis of OEPp.

Results

The chemical composition of OEPp was analyzed by mass spectrometry (GC/MS) and eight sesquiterpene compounds were identified, i.e. three major sesquiterpene (E-cariofilene, γ-muurolene, biciclogermacrene), and nine vouacapane diterpenes, four of which showed in major concentration (6α-acetoxyvouacapane, 6α,7β-dimetoxivouacapan-17-ene, 6α-acetoxy,7β-hidroxyvouacapane, 6α,7β-diacetoxycouacapane). Furthermore, the results of the present study demonstrate, for the first time, that the OEPp reduced mechanical allodynia in the postoperative pain and CRPS-I animal models. OEPp also increased the paw withdrawal latency in hot- and cold-plate tests in the postoperative pain model. In addition, the present work confirms and extends previous data from literature showing that systemic administration of OEPp caused significant inhibition against both phases of pain response to formalin intraplantar injection and edema formation.

Conclusions

Together, present and previous findings show that OEPp given intra-gastrically caused significant inhibition against both phases of formalin intraplantar injection and effectively inhibited mechanical and thermal hyperalgesia in the postoperative pain and CRPS-I animal models.  相似文献   
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