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61.
62.
Subjects infected with human immunodeficiency virus (HIV) have increased risk for atherosclerosis. Carotid artery intima-media thickness (IMT) assessed using ultrasound and coronary artery calcium (CAC) detected using computed tomography predict cardiovascular risk in the general population; however, their usefulness and comparability in patients with HIV are less well defined. The purpose of this study was to compare IMT and CAC in the detection of atherosclerosis in subjects with HIV. CAC and IMT were measured in 253 HIV-infected and 58 uninfected adults. Associations among HIV-related factors, traditional risk factors, and CAC and IMT were evaluated. The distribution of IMT among subjects with and without CAC was compared. Among the patients with HIV, 37% had detectable CAC compared to 28% of controls (p = 0.19); 16% of the patients with HIV had CAC >100 compared to 5% of controls (p = 0.03). With either detectable or undetectable CAC, HIV-infected subjects had higher IMT compared to controls (1.02 ± 0.34 vs 0.78 ± 0.12 mm, p <0.0001), even after adjustment for traditional risk factors. Among those with undetectable CAC, 34% of patients with HIV had markedly increased IMT (≥1 mm) compared to no controls (p <0.0001). HIV-related factors were associated with IMT but not with CAC. In conclusion, patients with HIV and controls had similar rates of detectable CAC, while absolute CAC scores were modestly higher in the HIV group. Conversely, carotid IMT detected advanced subclinical atherosclerosis in patients with HIV even in the absence of CAC. Thus, with HIV, IMT is associated with disease-related factors and may be a more sensitive indicator of subclinical atherosclerosis than CAC.  相似文献   
63.
64.

Objectives

To evaluate the effect of additives on the water sorption characteristics of Bis-GMA based copolymers and composites containing TEGDMA, CH3Bis-GMA or CF3Bis-GMA.

Material and methods

Fifteen experimental copolymers and corresponding composites were prepared combining Bis-GMA and TEGDMA, CH3Bis-GMA or CF3Bis-GMA, with aldehyde or diketone (24 and 32 mol%) totaling 30 groups. For composites, barium aluminosilicate glass and pyrogenic silica was added to comonomer mixtures. Photopolymerization was effected by 0.2 wt% each of camphorquinone and N,N-dimethyl-p-toluidine. Specimen densities in dry and water saturated conditions were obtained by Archimedes'' method. Water sorption and desorption were evaluated in a desorption-sorption-desorption cycle. Water uptake (%WU), water desorption (%WD), equilibrium solubility (ES; µg/mm3), swelling (f) and volume increase (%V) were calculated using appropriate equations.

Results

All resins with additives had increased %WU and ES. TEGDMA-containing systems presented higher %WU, %WD, ES, f and %V values, followed by resins based on CH3Bis-GMA and CF3Bis-GMA.

Conclusions

Aldehyde and diketone led to increases in the water sorption characteristics of experimental resins.  相似文献   
65.
Previous studies have shown that children with autism spectrum disorders (ASDs) have impaired executive function, disordered neural connectivity, and abnormal immunologic function. The present study examined whether these abnormalities were associated. Seventeen high-functioning (HFA) and 17 low-functioning (LFA) children with ASD, aged 8–17 years, participated voluntarily in the study. The two groups of children were compared on their general intelligence in terms of IQ; executive function as measured by the Hong Kong List Learning Test, D2 Test of Concentration, Five Point Test, Children's Color Trail Test, Tower of California Test, and Go/No-Go task; a non-executive task as measured by the Picture Completion Task; neural connectivity as measured by theta coherence in the anterior and posterior regions; and immunologic function as measured by the level of circulating CD3+ CD8+ suppressor/cytotoxic T lymphocytes in a blood sample. Results on executive function showed that LFA children performed significantly poorer than HFA children as shown on their lower Executive Composite as well as individual executive function scores. However, there was no group difference on the Picture Completion Task. Results on neural connectivity showed that LFA children demonstrated a different pattern of electroencephalography (EEG) coherence from HFA children as shown in the significantly elevated theta coherence in the anterior network, as well as at the left intra-hemispheric (LA-LP) and right-to-left inter-hemisphere (RA-LP) connections of LFA children. In immunologic function, results showed that LFA children had significantly elevated level of suppressor/cytotoxic T lymphocytes (CD3+ CD8+) (p < 0.05). In addition, the executive dysfunction, disordered neural connectivity, and abnormal immunologic function were found to be associated. These results provided some initial evidence to support the notion that immunologic factors are associated with neuronal damage, measureable by EEG coherence and manifested as executive dysfunctions.  相似文献   
66.

OBJECTIVES:

Hydroxychloroquine is an antimalarial agent that has been used in systemic lupus erythematosus and rheumatoid arthritis treatment for many years. Recently, novel mechanisms of action have been proposed, thereby broadening the therapeutic perspective of this medication. The purpose of this study was to evaluate the immunomodulatory activity of hydroxychloroquine in T helper 17 (Th17) cytokines in healthy individuals and patients.

METHODS:

Eighteen female patients with systemic lupus erythematosus (mean age 39.0±12.9 years) and 13 female patients with rheumatoid arthritis (mean age 51.5±7.7 years) were recruited from Universidade Federal de Pernambuco-Brazil. The patients were included after fulfilling four classification criteria for systemic lupus erythematosus or rheumatoid arthritis from the American College of Rheumatology. After being stimulated with phorbol 12-myristate 13-acetate and ionomycin in the absence or presence of different concentrations of hydroxychloroquine, the interleukin 6, 17 and 22 levels were quantified with an enzyme-linked immunosorbent assay in culture supernatants of peripheral blood mononuclear cells from healthy individuals and patients.

RESULTS:

We demonstrated that in peripheral blood mononuclear cells from healthy volunteers and in systemic lupus erythematosus and rheumatoid arthritis patients, there was a significant reduction in the IL-6, IL-17 and IL-22 supernatant levels after adding hydroxychloroquine.

CONCLUSIONS

Our in vitro results demonstrated that hydroxychloroquine inhibits IL-6, IL-17 and IL-22 production and contributes to a better understanding of the mechanism of action of this medication.  相似文献   
67.

Objective

This study aimed to investigate the expression of the MSH2 DNA repair protein in head and neck squamous cell carcinoma (HNSCC) in order to analyze its association with clinicopathologic factors and overall survival of patients.

Material and Methods

Clinical data and primary lesions of HNSSC were collected from 55 patients who underwent surgical resection with postoperative radiotherapy in Montes Claros, state of Minas Gerais, Brazil, between 2000 and 2008. Immunohistochemical reactions were performed to analyze MSH2 protein expression.

Results

Bivariate analysis showed no significant correlation or association between MSH2 expression and clinicopathologic parameters by Mann-Whitney and Kruskal-Wallis tests. Patients with locoregional metastatic disease (OR=4.949, p<0.001) and lower MSH2 immunohistochemical expressions (OR=2.943, p=0.032) presented poorer survival for HNSCC by Cox regression models.

Conclusions

Our data demonstrated that lower MSH2 expression might contribute to a higher clinic aggressiveness of HNSCC by promoting an unfavorable outcome.  相似文献   
68.
Background and Aim: Hepatitis C virus (HCV) infection is associated with impairment in health‐related quality of life (HRQOL). The purpose of this study was to evaluate HRQOL across the HCV disease spectrum using preference‐based (utility) and non‐preference‐based (psychometric) methods, adjusting for sociodemographic factors and co‐morbidity. Methods: Hepatitis C virus patients (n = 751) were recruited from several tertiary care settings in Vancouver, Canada for this observational, cross‐sectional cohort study. Patients completed the Health Utilities Index Mark 2/3, a self‐administered time trade‐off utility instrument, and the Hepatitis Quality of Life Questionnaire (SF‐36 with HCV‐specific items). We examined the association between HRQOL and disease stage using linear regression adjusting for age, education, marital status, income, and co‐morbidities. Results: Utility scores were low across disease stage and instrument, ranging from 0.51 to 0.80. On the SF‐36, the mean Physical Component Summary score ranged from 37.2 to 49.2 across disease stage, and the Mental Component Summary score ranged from 39.7 to 45.7 (United States norms = 50). In general, patients with viral clearance had the highest scores, and those with late‐stage disease (cirrhosis, liver cancer) had the lowest. Multivariable linear regression showed that the effect of disease stage was modest overall. Increasing age, lower income, unattached marital status, and high comorbidity were strongly associated with impairment in HRQOL. Conclusions: The effect of stage of disease on HRQOL is modest, although viral clearance is associated with higher HRQOL. HCV patients' HRQOL is strongly associated with concomitant illness and sociodemographic factors.  相似文献   
69.
Obesity is characterized by alterations in haemostatic processes that lead to a prothrombotic state. D-dimer (D-Di) is the last product of the fibrinolysis and may reflect the haemostatic balance. As the plasminogen activator inhibitor (PAI)-1 is the main inhibitor of fibrinolysis and it is elevated in obese, we hypothesize that negative correlation exists between PAI-1 and D-Di. In addition, we evaluated if plasma levels of PAI-1 and D-Di may be correlated with clinical parameters of adiposity [waist circumference and waist-to-hip ratio (WHR)]. We measured plasma PAI-1 and D-Di concentrations using ELISA in 60 women: 21 lean women without comorbidities and 39 obese women. We found higher levels of D-Di and PAI-1 in obese groups compared to control group (P < 0.05). No differences were observed between obese and obese untreated hypertensives. PAI-1 levels, but not of D-Di, are positively correlated with BMI (control, r = 0.44) and WHR (all obese, r = 0.40). Negative correlation was found between PAI-1 and D-Di in control (r = -0.56), no association was observed in obese, signalizing to a particular attention regarding the clinical use of D-Di. Our results indicate the magnitude of central obesity as a risk factor for development of disorders related to prothrombotic states.  相似文献   
70.
The objectives of this quantitative study were to (1) ascertain to what extent older adults aged 50 and above feel and desire to be younger than their age, and classify themselves as young versus old; (2) compare these patterns with those found among other cross-cultural populations; and (3) assess the extent to which self-rated health and life satisfaction predict age identities. This study was carried out on a sample of 500 dwellers of the Senegalese capital aged 50 and older. This sample was constructed using the quota method to strive for representativeness. Most of the respondents wanted to be younger than their chronological age (51.8 %), but only 27.8 % felt younger than they were. Moreover, 80 % of the sample claimed to be old. Self-rated health predicted felt age and the feeling of being old. Furthermore, the less-satisfied Dakar residents were with their life, the younger they wanted to be. We first discuss our results in a comparative perspective focused on how orientations toward individualism and collectivism could be related to age identity, and on demographic characteristics of the Senegalese population—where life expectancy is 59.3 years old. We then analyze the relevance of age identity dimensions as indicators of successful aging in Dakar.  相似文献   
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