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51.
The aim of this study was to investigate the respiratory function disorders that could be related to dust exposure during the production of copper mine in copper mineworkers (CMWs). The study included 75 male CMWs (mean age, 32.0 ± 7.1 years, 58.6% smokers) and 75 male age- and smoking status-matched healthy control subjects. Serum Cu level was significantly higher in the CMW group (0.80 ± 0.62 μg/ml) than the control group (0.60 ± 0.39 μg/ml) (p = 0.017). Significant negative correlations were found between serum Cu level and forced expiratory volume in first second (r = −0.600; p < 0.001) and between serum Cu level and forced vital capacity (r = −0.593; p = <0.001) in CMWs. Serum Cu level was significantly higher in the restrictive type pulmonary function disorders group (1.36 ± 0.62 μg/ml) than obstructive type (0.90 ± 0.55 μg/ml) and normal pulmonary function pattern group (0.53 ± 0.43 μg/ml) (p < 0.001). Patients with radiological parenchymal abnormalities had significantly higher serum copper levels than those without abnormalities (1.53 ± 0.52 vs. 0.71 ± 0.52 μg/ml, respectively; p = 0.002). In conclusion, result of the study has shown a negative association between pulmonary functions disorders and radiological abnormalities and serum Cu levels in CMWs.  相似文献   
52.

Introduction  

The aim of this study was to examine seroconversion and the relationship with age and inflammation of autoantibodies in a large group of patients attending an outpatient rheumatology clinic.  相似文献   
53.
With great interest, we read the article by Toms and colleagues [1] in the previous issue of Arthritis Research & Therapy, in which they assessed prevalences of metabolic syndrome (MetS) in rheumatoid arthritis (RA) patients. Moreover, they identified demographic and clinical factors that may be associated with MetS. Toms and colleagues found prevalences of up to 45% of MetS and demonstrated older age and health status (health assessment questionnaire) to be associated with MetS irrespectively of the definition used. Of most interest, an association between methotrexate (MTX) use and decreased presence of MetS was observed in patients more than 60 years of age. The investigators hypothesized that this may be attributed to a drug-specific effect (and not to an anti-inflammatory effect) either by changing levels of adenosine, which is known to interact with glucose and lipid metabolism, or by an indirect effect mediated through concomitant folic acid administration, thereby decreasing homocysteine levels.Recently, we also examined the prevalence of MetS in (a subgroup of) RA patients in the CARRÉ investigation, a prospective cohort study on prevalent and incident cardiovascular disease and its underlying cardiovascular risk factors [2]. The findings of Toms and colleagues stimulated us to perform additional analyses in our total study population (n = 353).The prevalences of MetS were 35% and 25% (Table (Table1)1) according to criteria of National Cholesterol Education Program (NCEP) 2004 and NCEP 2001, respectively. In multivariate backward regression analyses, we found significant associations between body mass index, pulse rate, creatinine levels, hypothyroidism and diabetes mellitus and the presence of MetS independently of the criteria used (Table (Table2).2). However, an independent association between single use of MTX or use of MTX in combination with other disease-modifying antirheumatic drugs, on the one hand, and a decreased prevalence of MetS, on the other hand, could not be demonstrated (even in the subgroup of patients over the age of 60).

Table 1

Characteristics of the study population
MetS presentaMetS absentaMetS presentbMetS absentb
n = 84n = 265n = 121n = 228P valueaP valueb
Demographics
 Age, years63.8 (± 8)63.1 (± 7)64.3 (± 8)62.7 (± 7)0.460.045
 Female, percentage766374620.0220.028
RA-related characteristics
 DAS284.2 (± 1.3)3.9 (± 1.4)4.1 (± 1.3)3.8 (± 1.4)0.210.062
 ESR, mm/hour22 (10-35)16 (9-30)20 (10-34)17 (9-31)0.0590.33
 CRP, mg/L11 (4-21)6 (3-16)8 (3-18)6 (3-19)0.0210.46
 RA duration, years7 (4-10)7 (4-10)7 (4-10)7 (5-10)0.830.19
 Erosion, percentage778379830.200.36
 Number of DMARDs1 (1-2)1 (1-1)1 (1-2)1 (1-1)0.260.43
 MTX current, percentage626063590.710.46
 MTX only, percentage393941380.950.67
 SSZ only, percentage8139140.230.22
 HCQ only, percentage14340.310.55
 Combination of DMARDs, percentage312529250.240.38
 TNF-blocking agent, percentage1191190.730.65
 Prednisolone only, percentage12311.000.42
Cardiovascular risk factors
 Current smoker, percentage263125320.420.15
 Pack-years, years17 (0-34)19 (2-38)19 (0-35)18 (2-38)0.230.75
 BMI, kg/m230 (± 4)26 (± 5)29 (± 4)25 (± 5)< 0.001< 0.001
 Creatinine, μmol/L89 (± 21)89 (± 16)91 (± 22)87 (± 14)0.990.070
 Renal clearance, mL/minute81 (± 24)72 (± 19)77 (± 23)73 (± 19)0.0030.062
 Pulse, beats per minute76 (± 11)73 (± 9)75 (± 11)73 (± 9)0.0050.015
 Diabetes mellitus, percentage143123< 0.0010.001
 Hypothyroidism, percentage122920.0010.003
Open in a separate windowaMetabolic syndrome (MetS) according to National Cholesterol Education Program (NCEP) 2001; bMetS according to NCEP 2004. Continuous variables are presented as means (± standard deviations) in cases of normal distribution or as medians (interquartile ranges) in cases of non-normal distribution. BMI, body mass index; CRP, C-reactive protein; DAS28, disease activity score using 28 joint counts; DMARD, disease-modifying antirheumatic drug; ESR, erythrocyte sedimentation rate; HCQ, hydroxychloroquine; MTX, methotrexate; RA, rheumatoid arthritis; SSZ, sulfasalazine; TNF, tumour necrosis factor.

Table 2

Variables associated with metabolic syndrome
UnivariateMultivariatea


OR95% CIP valueOR95% CIP value
Body mass index1.21.1-1.3< 0.0011.21.1-1.3< 0.001
Pulse1.031.01-1.060.0111.031.00-1.060.020
Creatinine1.011.00-1.020.0801.021.00-1.030.017
Hypothyroidism4.51.5-13.20.0074.71.5-15.00.009
Diabetes mellitus4.81.8-12.90.0024.51.4-15.20.014
Open in a separate windowaIn multivariate analyses, the following variables were used: gender, age, prednisolone only, methotrexate only, sulfasalazine only, hydroxychloroquine only, tumour necrosis factor-blocking agents, combination of disease-modifying antirheumatic drugs, pack-years, smoking, erosions, DAS28 (disease activity score using 28 joint counts), body mass index, pulse rate, creatinine levels, renal clearance, hypothyroidism and diabetes mellitus. CI, confidence interval; OR, odds ratio.Therefore, to get more support for a drug-specific effect, it is of interest to know whether or not in the study of Toms and colleagues the MTX effect was present only in the group of RA patients with single use of MTX or in the group of MTX-treated patients with other antirheumatic drugs. As patients with MetS were significantly older, it would give further information whether age was an independent risk factor for MetS in regression analyses. Moreover, as readers, we are not informed about comorbidities like diabetes and clinical hypothyroidism, which are notorious cardiometabolic risk factors. On the whole, we could not confirm a plausible protective role for the use of MTX and presence of MetS, and hence further investigation is required to explain the discrepancy between our findings and those of Toms and colleagues.  相似文献   
54.

Background  

The canonical core promoter elements consist of the TATA box, initiator (Inr), downstream core promoter element (DPE), TFIIB recognition element (BRE) and the newly-discovered motif 10 element (MTE). The motifs for these core promoter elements are highly degenerate, which tends to lead to a high false discovery rate when attempting to detect them in promoter sequences.  相似文献   
55.
56.

Background  

The fish, Erythrinus erythrinus, shows an interpopulation diversity, with four karyomorphs differing by chromosomal number, chromosomal morphology and heteromorphic sex chromosomes. Karyomorph A has a diploid number of 2n = 54 and does not have differentiated sex chromosomes. Karyomorph D has 2n = 52 chromosomes in females and 2n = 51 in males, and it is most likely derived from karyomorph A by the differentiation of a multiple X1X2Y sex chromosome system. In this study, we analyzed karyomorphs A and D by means of cytogenetic approaches to evaluate their evolutionary relationship.  相似文献   
57.

Introduction  

To investigate whether baseline levels of anti-citrullinated protein antibody (ACPA) or IgM rheumatoid factor (IgM-RF) and changes in the year thereafter are associated with disease activity, functional and radiographic outcome in early arthritis patients, and provide additional information over baseline autoantibody status.  相似文献   
58.
Little is known about past vegetation dynamics in Eastern Tropical South America (ETSA). Here we describe patterns of chloroplast (cp) DNA variation in Plathymenia reticulata, a widespread tree in the ETSA Atlantic Forest and Cerrado biomes, but not found in the xeromorphic Caatinga. Forty one populations, comprising 220 individuals, were analysed by sequencing the trnS‐trnG and trnL‐trnL‐trnF cpDNA regions. Combined, they resulted in 18 geographically structured haplotypes. The central region of the sampling area, comprising Minas Gerais and Goiás Brazilian states, is a centre of genetic diversity and probably the most longstanding area of the distribution range of the species. In contrast, populations from northeastern Brazil and the southern Cerrados showed very low diversity levels, almost exclusively with common haplotypes which are also found in the central region. Coupled with a long‐branched star‐like network, these patterns suggest a recent range expansion of P. reticulata to those regions from central region sources. The recent origin of the species (in the early Pleistocene) or the extinction of some populations due to drier and cooler climate during the last glacial maximum could have been responsible for that phylogeographic pattern. The populations from northeastern Brazil originated from two colonization routes, one eastern (Atlantic) and one western (inland). Due to its high diversity and complex landscape, the central region, especially central‐north Minas Gerais (between 15°–18° S and 42°–46° W), should be given the highest priority for conservation.  相似文献   
59.
60.
The influence of acid on astringency of alum and phenolic compounds   总被引:2,自引:1,他引:1  
Peleg  H; Bodine  KK; Noble  AC 《Chemical senses》1998,23(3):371-378
Astringency of aqueous solutions of phenolic compounds (grape seed tannins, tannic acid, catechin and gallic acid) increased upon addition of citric acid, whereas the astringency of alum was reduced. Astringency of alum was decreased equivalently by addition of equi-sour levels of lactic acid, citric acid or hydrochloric acid. The difference between alum and the phenolic compounds is speculated to result from chemical modifications affecting binding of the astringents with oral proteins rather than cognitive differences. Chelation of the aluminum ion in alum by acids reduces its availability for interacting with salivary proteins or epithelial proteins. In contrast, the increased astringency produced upon acidification of phenolic compounds is speculated to result from the pH driven increase in the affinity of the phenols for binding with proteins. These results suggest that alum cannot be used interchangeably with phenolic astringents in psychophysical studies.   相似文献   
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