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71.
OBJECTIVE: To investigate the role of the cytolytic action mediated by perforin in the course of rheumatoid arthritis (RA), we studied the immunophenotypic characteristics of lymphocytes containing perforin in peripheral blood (systemic level), in synovial fluid (SF), and in the synovial membrane (local level) in patients during the acute or chronic phase of RA. Cells from patients with osteoarthritis were used as controls. METHODS: Flow cytometry was used for simultaneous detection of intracellular (perforin) and cell surface antigens. Mean fluorescence intensity (MFI) was a measure of the mean perforin content per cell. Immunocytochemical staining was used to visualize perforin in the cytoplasmic compartment of cells. RESULTS: In acute RA highly significant changes in perforin expression were found in all compartments (peripheral blood, SF, and synovial membrane): (1) increase of percentage of total perforin positive cells; (2) increase of both subsets of cytolytic cells, T (CD8+P+) and NK (CD56+P+) cells; (3) increase in the frequency of perforin positive cells in CD8+ and CD56+ cell populations; and (4) the highest content of perforin/cell (MFI values) in all compartments, except in the synovial membrane. CONCLUSION: Perforin positive cells may participate in the acute phase of RA by maintaining and perpetuating inflammation and contributing to tissue destruction.  相似文献   
72.
The aim of this research was to determine if the age of healthy subjects older than 40 years of age has an influence on the concentration of β(2) -microglobulin in the serum of subjects of different populations. We examined the values of β(2) -microglobulin in the serum of 51 healthy subjects aged 40-86 years using the microparticle enzyme immunoassay AxSYM β(2) -microglobulin test. The reference values of β(2) -microglobulin according to the nonparametric statistical method is 0.95-2.73 mg/L. A correlation was found between β(2) -microglobulin and age: 40-50 years (0.94-1.54 mg/L), 51-65 years (0.96-2.62 mg/L), and >65 years (1.13-2.84 mg/L). There was no significant statistical difference of β(2) -microglobulin between genders (P > 0.05); however, there was a statistically significant difference between the concentration of β(2) -microglobulin and the subjects' age. (Spearman's rank correlation coefficient ρ = 0.66; P < 0.01). A direct correlation between age and the concentration of β(2) -microglobulin was observed. This research is a contribution to determining reference values of β(2) -microglobulin in subjects of different populations.  相似文献   
73.

Introduction and objectives

Several biomarkers have been used for evaluation and quantification of myocardial injury after effective ablation. We studied possible different thermal stability and usability of the proteins released by cardiac cells injured by different energy sources.

Methods

Firstly, we tested in vitro thermal stability of creatinine kinase (CK), myocardial bound creatinine kinase (CKMB), cardiac troponins I (cTnI) and cardiac troponins T (cTnT) in collected blood samples from 15 patients (pts) with confirmed ST-segment elevated myocardial infarction (STEMI). Secondly, the biomarkers were collected and analyzed in 82 pts treated with radiofrequency ablation (RFA) and in 79 pts treated with cryo-balloon ablation (CBA).

Results

In vitro experiment showed that all biomarkers were stable in low temperature of -30oC. Troponins were stable in the high temperatures analyzed. A substantial drop in CK and CKMB levels were measured at 50 °C and 40° C, respectively. In vivo study showed that the increase in CKMB levels was highly significant in CBA pts only. Pathological CKMB values were observed in 24% of RFA pts and 98% of CBA pts. Pathological cTnI values were observed in all pts and the rise in cTnI levels was highly significant in both groups after ablation.

Conclusions

Both in vitro and in vivo results show that CKMB cannot be used for quantitative determination of myocardial injury produced by radiofrequency energy. Only cardiac troponins reflect myocardial injury, regardless of energy source, and may be considered in future studies for comparison of biomarkers effects of cryo versus radiofrequency ablation.Full English text available from: www.revespcardiol.org  相似文献   
74.
AIM: To investigate efficacy and safety of cetuximab combined with two chemotherapy regimens in patients with unresectable metastatic colorectal cancer (mCRC). METHODS: Randomized patients received cetuximab with 5-fluorouracil (5-FU), folinic acid (FA) and oxaliplatin (FOLFOX) 6 (arm A, n = 74) or 5-FU, FA and irinotecan (FOLFIRI) (arm B, n = 77). KRAS mutation status was determined retrospectively in a subset of tumors (n = 117). RESULTS: No significant difference was found between treatment arms A and B ...  相似文献   
75.
Children with sickle cell disease (SCD) have a significant vascular morbidity, especially cerebral macrovasculopathy (CV), detectable by transcranial Doppler. This study aimed to identify risk factors for CV using longitudinal biological and clinical data in a SCD newborn cohort followed at the Robert Debre Reference centre (n = 375 SS/Sβ0). Median follow‐up was 6·8 years (2677 patient‐years). Among the 59 children presenting with CV, seven had a stroke. Overall, the incidence of CV was 2·20/100 patient‐years [95% confidence interval (95%CI): 1·64–2·76] and the incidence of stroke was 0·26/100 patient‐years (95%CI: 0·07–0·46). The cumulative risk of CV by age 14 years was 26·0% (95%CI: 20·0‐33·3%). Risk factors for CV were assessed by a Cox model encompassing linear multivariate modelling of longitudinal quantitative variables. Years per upper‐airway obstruction [Hazard ratio (HR) = 1·47; 95%CI: 1·05–2·06] or bronchial obstruction (HR = 1·76; 95% CI: 1·49–2·08) and reticulocyte count (HR = 1·82 per 50 × 109/l increase; 95%CI: 1·10–3·01) were independent risk factors whereas fetal haemoglobin level (HR = 0·68 per 5% increase; 95%CI: 0·48–0·96) was protective. Alpha‐thalassaemia was not protective in multivariate analysis (ancillary analysis n = 209). Specific treatment for upper or lower‐airway obstruction and indirect targeting of fetal haemoglobin and reticulocyte count by hydroxycarbamide could potentially reduce the risk of CV.  相似文献   
76.
Whilst autologous stem cell transplantation (auto‐SCT) is considered standard of care for relapsed/refractory classical Hodgkin lymphoma, the role of auto‐SCT in nodular lymphocyte‐predominant Hodgkin lymphoma (NLPHL) is not well defined due to limited data. We report the first study on auto‐SCT for NLPHL with a larger cohort. Eligible for this retrospective registry study were patients reported to the EBMT between 2003 and 2013, aged 18 or older with relapsed/refractory NLPHL who underwent first auto‐SCT with disease chemosensitive to salvage therapy. NLPHL transformed to diffuse large B cell lymphoma were excluded. Sixty patients (83% male; median age 40 years) met the eligibility criteria. The median time between diagnosis and transplant was 21 months (IQR 13–58), and the median number of prior treatment lines was 2 (range 1–5), including rituximab in 63% of the patients. At auto‐SCT, 62% of the patients were in complete remission (CR) and 38% in partial remission. Seventy‐two percent of the patients received BEAM as high‐dose therapy. With a median follow‐up of 56 months (range 3–105), 5‐year progression‐free and overall survival (OS) were 66% and 87%, respectively. Univariate comparisons considering age, time from diagnosis to transplant, prior chemotherapy lines, and prior rituximab use failed to identify significant predictors for any survival endpoint except for being in CR at the time of auto‐SCT (vs PR, P = .049) for OS. Auto‐SCT in patients with relapsed/refractory NLPHL who are sensitive to salvage therapy gives excellent disease control and long‐term survival independent of the time interval between diagnosis and transplant.  相似文献   
77.
Scand J Caring Sci; 2013; 27; 303–310 Physicians’ attitudes about interprofessional treatment of chronic pain: family physicians are considered the most important collaborators Aims and objectives: Interprofessional collaboration is the process in which different professional groups work together to positively impact health care. We aimed to explore physicians’ attitudes toward interprofessional collaboration in the context of chronic pain management with the implication that if attitudes are not positive, appropriate interventions could be developed. Design: A quantitative attitudes study. Ethical issues: The ethical committee approved the study. Methods: A web‐based survey about interprofessional treatment of chronic pain was administered to physicians. Outcome measures were as follows: physicians’ demographic and workplace information, previous experience of working within an interprofessional team, and attitudes towards interprofessional collaboration in chronic pain management. Results: There were 90 physicians who responded to the survey. Physicians had positive attitudes towards team work in the context of chronic pain, but they were undecided about sharing their role within an interprofessional team. The family physician was singled out as the most important as well as the most common collaborator in chronic pain treatment. Interprofessional educational seminars and workshops were suggested as methods for improving interprofessional collaboration. Conclusions: Interprofessional collaboration may be enhanced with continuing medical education that will bring together different healthcare professionals, enable them to exchange experiences and learn about their potential roles within a team.  相似文献   
78.
Previous studies have shown a paradoxical increase in early mortality in older patients (>70 years) with acute STEMI treated with fibrinolytic therapy (FT), which has been attributed to the development of free wall rupture (FWR). Our aim was to assess occurrence of FWR in STEMI patients receiving FT. In this 7-year prospective study, data from 1701 consecutive patients were obtained. We analyzed predictors of the in-hospital mortality in patients > 70 years old. The independent contribution of several variables to overall mortality and FWR development was assessed using multiple logistic regression analyses. The mortality of entire cohort was 18% (306/1701). Diabetes mellitus, anterior infarction, smoking, female gender and hypercholesterolemia were independent predictors of in-hospital mortality. FT was given to 18% of all patients (304/1701) of which 13% died (39/304). FWR was 18.4-times more often in patients who received FT. Among patients younger than 70 years who received FT there was no FWR, while in patients ≥70 years of age FWR was found in almost half of the deceased (30/68; 44%). Application of FT in STEMI patients is not associated with higher mortality, but significantly increases number of FWR, especially in patients over 70 years of age.  相似文献   
79.

Background

The cardiac renin–angiotensin system (RAS) has been implicated in mediating myocyte hypertrophy and remodeling, although the biochemical mechanisms responsible for regulating the local RAS are poorly understood. Caveolin-1 (Cav-1)/Cav-3 double-knockout mice display cardiac hypertrophy, and in vitro disruption of lipid rafts/caveolae using methyl-β-cyclodextrin (MβCD) abolishes cardiac protection.

Methods

In this study, neonatal rat ventricular myocytes (NRVM) were used to determine whether lipid rafts/caveolae may be involved in the regulation of angiotensinogen (Ao) gene expression, a substrate of the RAS system.

Results

Treatment with MβCD caused a time-dependent upregulation of Ao gene expression, which was associated with differential regulation of mitogen-activated protein (MAP) kinases ERK1/2, p38 and JNK phosphorylation. JNK was highly phosphorylated shortly after MβCD treatment (2–30 min), whereas marked activation of ERK1/2 and p38 occurred much later (2–4 h). β1D-Integrin was required for MβCD-induced activation of the MAP kinases. Pharmacologic inhibition of ERK1/2 and JNK enhanced MβCD-induced Ao gene expression, whereas p38 blockade inhibited this response. Adenovirus-mediated expression of wild-type p38α enhanced MβCD-induced Ao gene expression; conversely expression of dominant negative p38α blocked the stimulatory effects of MβCD. Expression of Cav-3 siRNA stimulated Ao gene expression, whereas overexpression of Cav-3 was inhibitory. Cav-1 and Cav-3 expression levels were found to be positively regulated by p38, but unaffected by ERK1/2 and JNK.

Conclusion

Collectively, these studies indicate that lipid rafts/caveolae couple to Ao gene expression through a mechanism that involves β1-integrin and the differential actions of MAP kinase family members.  相似文献   
80.
BackgroundEpidemiological studies have indicated smoking to be a risk factor for the progression of liver diseases. Nicotine is the chief addictive substance in cigarette smoke and has powerful biological properties throughout the body. Nicotine has been implicated in a number of disease processes, including increased cell proliferation and fibrosis in several organ systems.AimsThe aim of this study was to evaluate the effects of chronic administration of nicotine on biliary proliferation and fibrosis in normal rats.MethodsIn vivo, rats were treated with nicotine by osmotic minipumps for two weeks. Proliferation, α7-nicotinic receptor and profibrotic expression were evaluated in liver tissue, cholangiocytes and a polarized cholangiocyte cell line (normal rat intrahepatic cholangiocyte). Nicotine-dependent activation of the Ca2+/IP3/ERK 1/2 intracellular signalling pathway was also evaluated in normal rat intrahepatic cholangiocyte.ResultsCholangiocytes express α7-nicotinic receptor. Chronic administration of nicotine to normal rats stimulated biliary proliferation and profibrotic gene and protein expression such as alpha-smooth muscle actin and fibronectin 1. Activation of α7-nicotinic receptor stimulated Ca2+/ERK1/2-dependent cholangiocyte proliferation.ConclusionChronic exposure to nicotine contributes to biliary fibrosis by activation of cholangiocyte proliferation and expression of profibrotic genes. Modulation of α7-nicotinic receptor signalling axis may be useful for the management of biliary proliferation and fibrosis during cholangiopathies.  相似文献   
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