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31.
Hyaluronan attached to cell surface can form at least two very different structures; a pericellular coat close to plasma membrane and hyaluronan chains coalesced into “cables” that can span several cell lengths. The hyaluronan in cables, induced by many inflammatory agents, can bind leukocytes, whereas that in the pericellular coat does not contribute to leukocyte binding. Therefore, this structural change seems to have a major role in inflammation. In the present study we checked whether cells of squamous epithelium, like epidermal keratinocytes, can form hyaluronan cables and bind leukocytes. In addition, we checked whether hyaluronan synthesis is affected during the induction of cables. Control keratinocytes expressed pericellular hyaluronan as small patches on plasma membrane. But when treated with inflammatory agents or stressful conditions (tunicamycin, interleukin-1β, tumor necrosis factor-α, and high glucose concentration), hyaluronan organization changed into cable-like structures that avidly bound monocytes. Simultaneously, the total amount of secreted hyaluronan was slightly decreased, and the expression levels of hyaluronan synthases (Has1–3) and CD44 were not significantly changed. The results show that epidermal keratinocytes can form cables and bind leukocytes under inflammatory provocation and that these effects are not dependent on stimulation of hyaluronan secretion.  相似文献   
32.
Cervical artery dissection (CeAD) is a frequent cause of stroke among young patients. It is unclear how many CeADs occur asymptomatically or cause subtle and unspecific clinical symptoms. We hypothesize that CeAD remains often unrecognized. Accordingly, the incidence of CeAD might be higher and the stroke risk lower than generally assumed. Lack of CeAD-indicating clinical symptoms is regarded as the main cause of missed diagnoses. We further hypothesize that underrepresentation of asymptomatic and oligosymptomatic patients in CeAD studies may have biased the association between ischemia and local symptoms in CeAD patients as well as the associations of CeAD with risk factors or co-morbidities. We finally hypothesize that symptomatic CeAD may be preceded by an initial asymptomatic phase. According to this final hypothesis, the time of onset of CeAD should be considered uncertain. The issue of unrecognized CeAD is relevant, as it may affect the associations between CeAD and putative risk factors. Furthermore, the existence of clinically silent CeADs may explain why recurrent and familial CeAD have been rarely observed.  相似文献   
33.
Prostate cancer (PrCa) is the most common male cancer in developed countries and the second most common cause of cancer death after lung cancer. We recently reported a genome-wide linkage scan in 69 Finnish hereditary PrCa (HPC) families, which replicated the HPC9 locus on 17q21-q22 and identified a locus on 2q37. The aim of this study was to identify and to detect other loci linked to HPC. Here we used ordered subset analysis (OSA), conditioned on nonparametric linkage to these loci to detect other loci linked to HPC in subsets of families, but not the overall sample. We analyzed the families based on their evidence for linkage to chromosome 2, chromosome 17 and a maximum score using the strongest evidence of linkage from either of the two loci. Significant linkage to a 5-cM linkage interval with a peak OSA nonparametric allele-sharing LOD score of 4.876 on Xq26.3-q27 (ΔLOD=3.193, empirical P=0.009) was observed in a subset of 41 families weakly linked to 2q37, overlapping the HPCX1 locus. Two peaks that were novel to the analysis combining linkage evidence from both primary loci were identified; 18q12.1-q12.2 (OSA LOD=2.541, ΔLOD=1.651, P=0.03) and 22q11.1-q11.21 (OSA LOD=2.395, ΔLOD=2.36, P=0.006), which is close to HPC6. Using OSA allows us to find additional loci linked to HPC in subsets of families, and underlines the complex genetic heterogeneity of HPC even in highly aggregated families.  相似文献   
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35.
In the present study we aimed to investigate the incidence and predictors of spirometry based airway obstruction in a representative population-based sample. Altogether 3,863 subjects, 1,651 males and 2,212 females aged ≥30 years had normal spirometry in year 2000. Fifty-three percent of them were never and 23% current smokers. A re-spirometry was performed 11 years later. Several characteristics, such as level of education, use of alcohol, physical activity, diet using Alternate healthy eating (AHEI) index, body mass index, circumwaist, sensitive C reactive protein (CRP) and cotinine of the laboratory values and co-morbidities including asthma, allergic rhinitis, sleep apnoea and chronic bronchitis, as potential risk factors for airway obstruction were evaluated. Using forced expiratory volume in one second/ forced vital capacity below the lower limit of normal, we observed 124 new cases of airway obstruction showing a cumulative 11-year incidence of 3.2% and corresponding to an incidence rate of 5.6/1,000 per year (PY). The incidence rate was higher in men than in women (6.3/1,000 PY vs. 5.0/1,000 PY, respectively). The strongest risk factors were current smoking (Odds ratio [OR] 2.5) and previously diagnosed asthma (OR 2.1). Sensitive CRP associated with the increased risk and high AHEI index with the decreased risk of airway obstruction. Using the similar study approach our findings on the incidence of airway obstruction are in line with the previously published figures in Europe. We were able to confirm the recent findings on the protective effect of healthy diet.  相似文献   
36.
AIM: To investigate the impacts of gender, age and factors of life style (alcohol, overweight, coffee and smoking) on serum liver enzymes.METHODS: Serum alanine aminotransferase (ALT) and gamma-glutamyltransferase (GGT) were measured from 6269 apparently healthy individuals (2851 men, 3418 women, mean age 45 ± 12 years, range 25-74 years) in a national cross-sectional health survey. All subjects underwent detailed clinical examinations and interviews including the amount and pattern of alcohol use, coffee consumption and smoking habits.RESULTS: In this population with a mean ± SD alcohol consumption of 65 ± 105 g/wk and body mass index (BMI) of 26.1 ± 4.3 kg/m2, both ALT and GGT were significantly influenced by alcohol use (P < 0.001) and BMI (P < 0.001), whereas smoking increased only GGT (P < 0.001). A significant effect of age on ALT was seen in men (P < 0.001) whereas not in women. Significant two-factor interactions of alcohol use in men were observed with age (ALT: P < 0.01; GGT: P < 0.001) and BMI (GGT: P < 0.05). For ALT, a significant interaction also occurred between BMI and age (P < 0.005). In contrast, women showed significant interactions of alcohol use with BMI (GGT: P < 0.05), smoking (GGT: P < 0.001), and coffee consumption (GGT: P < 0.001).CONCLUSION: Life-style associated changes in liver enzymes may reflect health risks, which should be considered in the definition of normal limits for liver enzymes.  相似文献   
37.
The study aimed to clarify the role of direct bronchial artery revascularization (BAR) after en bloc double-lung (DLT) and heart-lung transplantation (HLT). Group I comprised eight patients with en bloc DLT or HLT and successful BAR, while group II included 14 DLT or HLT cases without BAR or with failed BAR. From these groups, 2 subgroups were extracted: group III, including 6 cases of en bloc DLT with successful BAR and group IV 10 HLT cases without or with failed BAR. Airway healing was evaluated at bronchoscopy and patency of BAR with angiography. Pulmonary viral, bacterial and fungal infections, rejections and bronchiolitis obliterans syndrome (BOS) were registered. Tracheal healing at 2 weeks and 3 months was better in group I than in group II (p = 0.003 and p = 0.05, respectively). Compared with group IV, tracheal anastomotic healing at 2 weeks was better in group III (p = 0.007) and tended to be better also after 3 months (p = 0.07). The incidence of infections, rejection or BOS did not differ between groups I and II. BAR thus improved healing of tracheal anastomosis.  相似文献   
38.
Objectives. Atherosclerosis is a systemic disease affecting several vessels of the body. Coronary artery patients requiring bypass surgery have increased prevalence of carotid artery atherosclerosis which is known to increase operative risk in coronary artery bypass surgery (CABG). Radial artery is often screened for grafting purposes preoperatively. Our aim was to find out whether atherosclerotic changes in forearm vessels are correlated and could reveal risk to carotid artery disease. Design. Eighty-five patients planned for elective CABG were examined with ultrasonography preoperatively. Biplane ultrasonographic scanning was performed on forearm arteries and both carotid arteries. Results. Eleven patients had pathologic changes in the wall of forearm vessels. Carotid artery disease was found on 19 patients. Forearm vessel pathology was found to have correlation to carotid artery disease. When forearm arteries show atherosclerotic pathology the risk of having carotid disease is at least five-fold, in subgroups even higher. Conclusions. Forearm arterial pathology is correlated to carotid artery disease. When forearm vessel pathology is evident in preoperative examination, scanning of the carotid vessels should be considered.  相似文献   
39.

Background

Several members of the GIMAP gene family have been suggested as being involved in different aspects of the immune system in different species. Recently, a mutation in the GIMAP5 gene was shown to cause lymphopenia in a rat model of autoimmune insulin‐dependent diabetes. Thus it was hypothesised that genetic variation in GIMAP5 may be involved in susceptibility to other autoimmune disorders where lymphopenia is a key feature, such as systemic lupus erythematosus (SLE).

Material and methods

To investigate this, seven single nucleotide polymorphisms in GIMAP5 were analysed in five independent sets of family‐based SLE collections, containing more than 2000 samples.

Result

A significant increase in SLE risk associated with the most common GIMAP5 haplotype was found (OR 1.26, 95% CI 1.02 to 1.54, p = 0.0033). In families with probands diagnosed with trombocytopenia, the risk was increased (OR 2.11, 95% CI 1.09 to 4.09, p = 0.0153). The risk haplotype bears a polymorphic polyadenylation signal which alters the 3′ part of GIMAP5 mRNA by producing an inefficient polyadenylation signal. This results in higher proportion of non‐terminated mRNA for homozygous individuals (p<0.005), a mechanism shown to be causal in thalassaemias. To further assess the functional effect of the polymorphic polyadenylation signal in the risk haplotype, monocytes were treated with several cytokines affecting apoptosis. All the apoptotic cytokines induced GIMAP5 expression in two monocyte cell lines (1.5–6 times, p<0.0001 for all tests).

Conclusion

Taken together, the data suggest the role of GIMAP5 in the pathogenesis of SLE.  相似文献   
40.
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