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Human–Structure Interaction (HSI) can significantly influence the dynamic characteristics of pedestrian footbridges, particularly those distinguished by their lightness and slenderness. This study examines the performance of Tuned Mass Dampers (TMD) and Semi-Active Tuned Mass Dampers (STMD) on pedestrian footbridges when their modal parameters change due to the influence of HSI. For this purpose, a 30 m long simply-supported footbridge with linear mass values ranging from 200kg/m to 2000kg/m and a fundamental frequency varying from 1Hz to 5Hz has been considered. In addition, several pedestrian streams with different pedestrian densities have been used to assess the structural dynamic response. The analysis highlights that structural lightness and slenderness are critical factors in determining whether the incorporation of an HSI model is relevant to accurately predict the dynamic performance of the structure. The findings indicate that while TMDs can become ineffective due to shifts in natural frequencies caused by HSI, resulting in a degradation of vibration reduction from 70–75% to 40–45%, STMDs demonstrate a robust capability to adjust and cope with these frequency changes, maintaining a higher average vibration reduction of around 55–60%. Consequently, STMDs emerge as a necessary solution for very slender structures where HSI significantly alters the global frequency response. This study highlights the importance of considering HSI in the design and implementation of damping solutions to ensure optimal functionality and user comfort on lightweight pedestrian bridges. [ABSTRACT FROM AUTHOR]

The artical offers information on a study that examine any association between low levels of 25-hydroxyvitamin D (25(OH)D) and insulin resistance (IR) in women with systemic lupus erythematosus (SLE). Topics discussed include the homeostatic model assessment, inflammation markers and seasonal variation.

Objective: The aim of this study was to evaluate the relevance of genetic variants of interleukin receptor-associated kinase-M (IRAK-M) (rs11465955, rs1624395, rs1152888 and rs1370128) and single immunoglobulin IL1-1R-related molecule (SIGIRR) (rs3210908) genes in systemic lupus erythematosus (SLE) in four independent European-descent populations. Methods: Our study population consisted of a total of 2033 SLE patients and 2357 healthy controls from Spain, Germany, Italy and Argentina. The genotyping was performed using a polymerase chain reaction (PCR) system with pre-developed TaqMan allelic discrimination assay. Genetic association between the genotyped markers was determined by PLINK v1.07. Results: After a meta-analysis including these four populations, a trend of association between rs11465955 (Pmeta-analysis = 0.06), rs1370128 (Pmeta-analysis = 0.07) and rs1624395 (Pmeta-analysis = 0.06) polymorphisms was found. However, these differences did not reach statistical significance. In addition, we did not find any association between SLE and the rs1152888 IRAK-M (Pmeta-analysis = 0.13) and the rs3210908 SIGIRR (Pmeta-analysis = 0.40) polymorphisms after the meta-analysis. No evidence of association with IRAK-M haplotypes was found. Conclusion: These results suggest that the tested variations of IRAK-M and SIGIRR genes do not confer a relevant role in the susceptibility to SLE in European-descent populations. [ABSTRACT FROM AUTHOR]

Objective: The aim of the study was to determine the clinical and psychological factors linked to health-related quality of life (HRQOL) in patients with systemic lupus erythematosus (SLE) and test the effectiveness of cognitive behavioural therapy in changing these factors. Methods: We evaluated 34 patients with SLE over a period of 15 months. In order to study the variables related to items of QOL and the physical (PCS) and mental (MCS) component summaries of the SF-36, several multiple linear regression models were constructed. Patients were randomized and distributed into two similar groups; one of them received cognitive behavioural therapy and the other received the usual controlled care. The psychological aspects as well as the related-disease factors were evaluated four times during the study. Results: Self-perceived stress (R2 corrected: 0.314, t: -2.476, p < 0.021), vulnerability to stress (R2 corrected: 0.448, T: -2.166, p < 0.04) and anxiety (R2 corrected: 0.689, T: -7.294, p < 0.00) were predictor variables of MCS. The group of patients who received the therapy improved their level of physical role functioning, vitality, general health perceptions and mental health, compared with the group of patients who only received conventional care. Conclusion: QOL usually depends on multiple factors, some of which are stress and anxiety, which can be modified by a cognitive behavioural therapy, in order to obtain a significant improvement in the HRQOL, irrespective of the activity level of the disease. Frequent evaluations of the quality of life in patients with SLE and psychological treatment should also be considered. Lupus (2010) 19, 1632—1639. [ABSTRACT FROM AUTHOR]

The objective of this article was to evaluate whether serum uric acid (SUA) correlates with arterial stiffness and inflammation markers in a cohort of women with systemic lupus erythematosus (SLE) without overt atherosclerotic cardiovascular diseases, who attended a community hospital. One hundred and two women with SLE were assessed as part of this cross-sectional study. Carotid-femoral pulse wave velocity (PWV) was measured using an automatic device (Complior®). C-reactive protein (CRP), fibrinogen and homocysteine levels as well as other metabolic results were recorded. Duration and activity of SLE, damage accrual and treatments were recorded. SLE women were categorized as having or not having hyperuricaemia (HU) according to SUA levels (greater than or up to 6.2 mg/dl, respectively). A multiple linear regression analysis was used to determine the independent link between SUA levels and other variables. Women with SLE and HU (n=15, 15%) had a worse cardiovascular risk profile that included ageing, hypertension, obesity, higher total cholesterol levels, renal failure and presence of metabolic syndrome. Also, the duration of SLE was increased and damage accrual was greater. In the unadjusted analysis, SUA levels correlated with PWV, CRP, fibrinogen and homocysteine. However, in a multivariate linear regression analysis, SUA levels independently correlated with the duration of SLE, creatinine, total cholesterol and homocysteine levels but did not correlate with PWV. In conclusion, SUA was associated with arterial stiffness, but not independently of age and homocysteine levels. Nevertheless, SUA might be an ancillary indicator of subclinical atherosclerosis in SLE women without clinically evident atherosclerotic cardiovascular disease. [ABSTRACT FROM AUTHOR]

To determine the "in-vitro" intrinsic cell radiosensitivity (RS) as a risk indicator of radiation-related side-effects in patients with systemic lupus erythematosus (SLE) compared with healthy subjects (control group). Moreover, we elucidated if clinical, therapeutic and biological parameters could affect the "in-vitro" intrinsic RS in patients with SLE. Intrinsic RS was determined by the quantification of the initial radiation-induced DNA double-strand breaks in peripheral lymphocytes, measured by pulsed-field gel electrophoresis from 52 patients with SLE and a control group consisting of 48 sex- and age-matched healthy subjects. No difference in intrinsic RS was found among both groups. However, SLE patients with anaemia, increased erythrocyte sedimentation rate and those with positive result for anti-La/SSB and anti-RNP antibodies showed significantly higher DNA double-strand breaks than those without them. In our study, patients with SLE did not have a higher intrinsic RS than healthy subjects. According to these results, and with the caution of being a limited laboratory study, the use of radiotherapy should not be avoided in patients with SLE when it is clinically needed. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the potential role of three IRF3 gene polymorphisms (rs2304204, rs7251 and rs2304207) with systemic lupus erythematosus (SLE). Our study population consisted of 610 patients with SLE and 730 healthy controls. All individual were of Spanish Caucasian origin. The IRF3 polymorphisms were genotyped using a PCR system with pre-developed TaqMan allelic discrimination assay. No statistically significant differences were found when allele and genotype distribution of rs2304204, rs7251 and rs2304207 polymorphisms were compared between patients with SLE and controls [overall P values: rs7251, P = 0.06; rs2304204, P = 0.26 and rs2304207, P = 0.36, by chi-squared test on a 3 x 2 contingency table. Overall allelic P values: rs7251, P = 0.8, OR (95%CI) = 1.03 (0.87-1.22); rs2304204, P = 0.2, OR (95%CI) = 1.12 (0.93-1.34) and rs2304207, P = 0.8, OR (95%CI) = 1.02 (0.82-1.26)]. In addition, no evidence of association with haplotypes and clinical features of SLE was found. Our data suggest that the IRF3 polymorphisms do not appear to play a major role in the susceptibility or severity of SLE in a Spanish population. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the possible effects of the daily stress experienced during a six-month period on the cognitive functioning of patients with systemic lupus erythematosus (SLE). For this purpose, we evaluated the daily stress of 21 patients with lupus every day for six months. Later, we carried out a neuropsychological exam that included an evaluation of attention and memory. At the same time, scores on depression and anxiety were recorded with the objective of controlling other emotional variables that might be influencing these cognitive processes. The results show that daily stress was able to predict the scores on the neuropsychological variables studied. Specifically, the daily stress experienced in the previous six months is the variable with the greatest explanatory-predictive power on the scores for delayed recall visual memory, visual fluency and attention speed. This relationship proved to be negative in all three cases (R2 corr = 0.290; t = -2.712, P < 0.014); (R2 corr = 0.318; t = -2.818, P < 0.012); (R2 corr = 0.319; t = -2.906, P < 0.009), which means that the greater the daily stress, the lower the score on visual memory, fluency and total attention speed. We can state that daily stress is related to impairments in visual memory, fluency and attention in patients with SLE. This effect was not found with other emotional variables, such as depression and anxiety. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the possible association between the p53 suppressor gene codon 72 polymorphism and systemic lupus erythematosus (SLE). Our study population consisted of 513 SLE patients and 567 healthy controls. All the individuals were of Spanish Caucasian origin. Genotyping of the p53 codon 72 polymorphism was performed by allele-specific PCR. No statistically significant differences were observed between SLE patients and healthy controls when p53 codon 72 genotype and allele frequencies were compared. In addition, no evidence for association with clinical subfeatures of SLE was found. In conclusion, the p53 codon 72 polymorphism associated with SLE in a Korean population does not appear to play a major role in the susceptibility or severity of SLE in the Spanish population. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Pneumococcal Cellulitis in a Patient With Systemic Lupus Erythematosus: A Case Report and Review."

Nuclear factor (NF)-κB plays an important role in inflammatory diseases such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). A functional insertion/deletion polymorphism (−94ins/delATTG) has been identified in the promoter of theNFKB1gene. In addition, a polymorphic dinucleotide repeat (CA) has been identified in proximity to the coding region of the humanNFKB1gene. The aim of the present study was to investigate the influence of both the−94ins/delATTG and the (CA) microsatelliteNFKB1polymorphisms in the susceptibility/severity of RA and SLE. We analyzed the distribution of−94ins/delATTG and the multiallelic (CA)n repeat in 272 RA patients, 181 SLE patients, and 264 healthy controls from Southern Spain, in both cases using a polymerase chain reaction-fluorescent method. No statistically significant difference in the distribution of the−94delATTGNFKB1genotypes and alleles between RA patients, SLE patients, and control subjects was observed. Similarly, we found no statistically significant differences in the (CA)n microsatellite allele frequency between controls and RA patients or SLE patients. In addition, no association was found between the above mentionedNFKB1polymorphisms with any of the demographic and clinical parameters tested either in RA or in SLE patients. From these results, it seems that the−94ins/delATTG and the (CA)n repeat ofNFKB1gene may not play a relevant role in RA and/or SLE in our population. [ABSTRACT FROM AUTHOR]

The etiological role of hair dye treatment (HDT), some of them such as permanent hair dyes containing aromatic amines, in the development of SLE has been previously ruled out. However, the possible influence of HDT use on the course and prognosis of lupus patients has been assessed only in one short-term study. Since HDT is very extensive among the population, the knowledge of this possible negative effect may be very important. Thus, the aim of this study was to assess the long-term influence of several HDTs on the course and clinical severity of patients with both systemic lupus erythematosus (SLE) and cutaneous lupus (CL). In this longitudinal case series study, 91 SLE patients and 22 CL patients were prospectively studied from October 1988 to May 2000. They were divided into three groups: (a) non-HDT users - patients who have never used HDT (n = 65); (b) P-HDT users - HDT permanent type users, alone or in combination with other types of HDT (n = 28); (c) non P-HDT - users of other treatments different from permanent tinting (bleach, lowlights, etc; n = 20). In each patient we determined: (1) number of flares/year in SLE patients and worsening of cutaneous lesions for CL; (2) Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) damage index; (3) predominant damaged organs/systems according to the HDT use and type of HDT; and (4) subjective impression about the disease evolution in relation to HDT use. No significant differences were found with respect to flares/year and SLICC/ACR damage index between the study groups. Non-HDT group presented more renal involvement and serositis than both HDT-user groups. No patient related the HDT use to the worsening of his disease. Therefore, in this study no evidence of an association between the long-term use of several types of HDT and the clinical activity and course of SLE and CL was found. [ABSTRACT FROM AUTHOR]

Catastrophic antiphospholipid syndrome (CAPS) is a rare complication of antiphospholipid syndrome. lt is a disseminated severe vascular pathology which presents with multi-organic dysfunction that progresses rapidly. Prognosis ends up being fatal in half of the cases. It may appear during pregnancy, surgery, infection, or after suspension of anticoagulation therapy. We studied two female patients with CAPS who survived after treatment with anticoagulation therapy and intravenous corticosteroids. The evolution of our two patients, after 17 months of follow-up under oral anticoagulant treatment was favourable and they are currently asymptomatic. In these patients the early diagnosis and treatment were essential to enhance their possibilities of survival. [ABSTRACT FROM AUTHOR]