Human Health Risk Assessment of Environmental Exposure to Organochlorine Compounds in the Catalan Stretch of the Ebro River,Spain

In this study, the environmental impact and human health risks associated with exposure to organochlorine compounds (OCs) through soils and tap water in the Catalan stretch of the Ebro River, Spain, were investigated. The concentrations of polychlorinated biphenyls, hexachlorocyclohexanes, as well as DDT and derivates, were determined. Relatively low levels of these pollutants were observed, with mean concentrations ranging between 0.51–315.8 μg/kg and 0.05–74.6 ng/L in soil and tap water, respectively. These values are similar to those found in a number of recent surveys over the world. In spite of the presence of a chlor-alkali plant located upstream the Ebro River, which could mean a potential source of pollution, the current levels of OCs should not mean significant additional health risks for the local population.     

Clinical and sociodemographic variables associated with the onset of posttraumatic stress disorder in road traffic accidents

Our objective was to identify variables related to the onset of acute posttraumatic stress disorder (PTSD) after a road traffic accident. We evaluated 60 victims of a motor vehicle accident (MVA) in 2004 at 2 months postaccident. Thirty of them had developed PTSD; the other 30 had not developed PTSD. Clinical data, physical injuries, and sociodemographic characteristics were determined in 60 victims. The Davidson Trauma Scale (DTS) and a Structured Clinical Interview for DSM-IV (SCID) were used to evaluate PTSD occurrence. PTSD scores assessed by DTS and SCID at 2 months were significantly and positively associated with female sex, severe physical injuries, perceived social deprivation, and loss of job activity due to the accident. Female sex, severe physical injury, perceived social deprivation, and sick leave were related to the diagnosis of PTSD 2 months after the accident.     

Novel pharmacological targets based on receptor heteromers

Studies performed in the last 10 years have provided solid evidence indicating that G-protein-coupled receptors are expressed on the plasma membrane as homo and heterodimers. The first consequence of this fact is that homo and heterodimers are the true targets of natural (hormones, neurotransmitters) and synthetic drugs. Furthermore a given receptor in a heteromer may display a different functional and/or pharmacological profile than the same receptor characterized as monomer or as homodimer. Recent evidence indicates that receptor heteromers are sensors that lead to a fine-tuning in neurotransmission or hormone regulation; mainly this is achieved by a modification of the signaling pathways activated via a given receptor when it is forming a given heteromer. Quite often antagonists display variable affinities when a given receptor is expressed with different heteromeric partners. This fact should be taken into account in the development of new drugs. Finally it should be pointed out that radioligand binding data has to be analyzed by a model that considers receptors as dimers and not as monomers. This model provides a novel approach to characterize drugs interacting with the orthosteric center (agonists/antagonists) or with allosteric centers (allosteric regulators).     

Development of a hinge compatible with the kinematics of the knee joint

This study aims to present a new concept of a knee hinge based on a crossed four-bar linkage mechanism which has been designed to optimally follow a motion curve representing the knee kinematics in the position at which the knee hinge should be placed. The methodology used to determine the optimal knee hinge is based on the optimization of certain variables of the crossed four-bar mechanism using genetic algorithms in order to follow a certain motion curve, which was determined using a biomechanical model of the knee motion. Two current, commercially available knee hinges have been used to theoretically determine their motion by means of the path performed by their instantaneous helical axis. Comparison between these two different knee hinges, Optimal Knee Hinge and the theoretical motion performed by a human knee reveals that a common monocentric hinge has a maximum misalignment of up to 27.2 mm; a polycentric hinge has a maximum misalignment of 23.9 mm. In contrast, the maximum misalignment produced by the Optimal Knee Hinge is 1.99 mm. The orthotic joint presented significantly improves the kinematical compatibility and the adjustment between orthotic and human joint motion, and should provide several advantages in terms of comfort and safety. Furthermore, the determination of the instantaneous helical axis for a particular user, by means of human movement measurement techniques, will enable the optimal crossed four-bar mechanisms to be determined in a customized and personalized manner. As a consequence, this new concept of orthotic knee joint design may improve the adaptability of lower limb orthoses for the user, and may lead to significant advantages in the field of orthotics for the lower limb.     

Socioeconomic inequalities in alcohol related cancer mortality among men: To what extent do they differ between Western European populations?

We aim to study socioeconomic inequalities in alcohol related cancers mortality [upper aerodigestive tract (UADT) (oral cavity, pharynx, larynx, oesophagus and liver)] in men and to investigate whether the contribution of these cancers to socioeconomic inequalities in cancer mortality differs within Western Europe. We used longitudinal mortality datasets, including causes of death. Data were collected during the 1990s among men aged 30-74 years in 13 European populations [Madrid, the Basque region, Barcelona, Turin, Switzerland (German and Latin part), France, Belgium (Walloon and Flemish part, Brussels), Norway, Sweden, Finland]. Socioeconomic status was measured using the educational level declared at the census at the beginning of the follow-up period. We conducted Poisson regression analyses and used both relative [Relative index of inequality (RII)] and absolute (mortality rates difference) measures of inequality. For UADT cancers, the RII's were above 3.5 in France, Switzerland (both parts) and Turin whereas for liver cancer they were the highest (around 2.5) in Madrid, France and Turin. The contribution of alcohol related cancer to socioeconomic inequalities in cancer mortality was 29-36% in France and the Spanish populations, 17-23% in Switzerland and Turin, and 5-15% in Belgium and the Nordic countries. We did not observe any correlation between mortality rates differences for lung and UADT cancers, confirming that the pattern found for UADT cancers is not only due to smoking. This study suggests that alcohol use substantially influences socioeconomic inequalities in male cancer mortality in France, Spain and Switzerland but not in the Nordic countries and nor in Belgium.     

Rituximab‐induced interleukin‐15 reduction associated with clinical improvement in rheumatoid arthritis

Rituximab therapy alters all aspects of B‐cell participation in the disturbed immune response of rheumatoid arthritis patients. To determine the impact of B‐cell depletion on other immune compartments, we analysed levels of soluble and surface interleukin‐15 (IL‐15) along with the frequency of IL‐15‐related subsets after rituximab treatment. We then studied the correlation of observed changes with clinical activity. Heparinized blood samples from 33 rheumatoid arthritis patients were collected on days 0, 30, 90 and 180 after each of three rituximab cycles. Serum cytokine levels were determined by ELISA. Interleukin‐15 trans‐presentation was analysed by cytometry. Flow cytometry with monoclonal antibodies was performed to analyse circulating cell subsets. Interleukin‐15 was detected in the serum of 25 patients before initiating the treatment. Rituximab then progressively reduced serum IL‐15 (138 ± 21 pg/ml at baseline, 48 ± 18 pg/ml after third cycle, P = 0·03) along with IL‐17 (1197 ± 203 pg/ml at baseline, 623 ± 213 pg/ml after third cycle, P = 0·03) and tended to increase the frequency of circulating regulatory T cells (3·1 ± 1 cells/μl at baseline, 7·7 ± 2 cells/μl after third cycle). Rituximab also significantly decreased IL‐15 trans‐presentation on surface monocytes of patients negative for IL‐15 serum (mean fluorescence intensity: 4·82 ± 1·30 at baseline, 1·42 ± 0·69 after third cycle P = 0·05). Reduction of serum IL‐15 was associated with decrease in CD8⁺ CD45RO⁺/RA⁺ ratio (1·17 ± 0·21 at baseline, 0·36 ± 0·06 at third cycle, P = 0·02). DAS28, erythrocyte sedimentation rate and C‐reactive protein correlated significantly with CD8⁺ CD45RO⁺/RA⁺ ratio (R = 0·323, R = 0·357, R = 0·369 respectively, P < 0·001). Our results suggest that sustained clinical improvement after rituximab treatment is associated with IL‐15/memory T‐cell‐related mechanisms beyond circulating B cells.     

Social inequalities in the association between partner/marital status and health among workers in Spain

The objectives of this study are to examine the association between partner/marital status and several health outcomes among workers and to assess whether it depends on gender and occupational social class. The sample was composed of all workers aged 21-64 years interviewed in the 2006 Spanish National Health Survey (8563 men and 5881 women). Partner/marital status had seven categories: married and living with the spouse (reference category), married and not living with the spouse, cohabiting, single and living with parents, single and not living with parents, separated/divorced and widowed. Four health outcomes were analysed: self-perceived health status, mental health, psychiatric drugs consumption and hypertension. Multiple logistic regression models stratified by sex and social class were fitted. Female manual workers who were cohabiting were more likely to report poor self-perceived health status, poor mental health status, psychiatric medication consumption and hypertension than their married and living with the spouse counterparts. In that group the prevalence of poor health outcomes was even higher when compared with single people. Among male non-manual workers, being married and not living with the spouse was associated with poor self-perceived health status, poor mental health status and hypertension. There were almost no differences in health between being married and the rest of partner/marital status categories for different combinations of gender and social class and, even, some groups of single people reported better health outcomes than people who were married. Our results show no evidence that being married and living with the spouse is unequivocally linked to better health status among Spanish workers. They emphasize the importance of not only considering marital status, but also partner status, as well as the role of gender, social class and the sociocultural context in the analysis of the association between family characteristics and health.     

Plasmodium falciparum malaria in splenectomized patients: two case reports in French Guiana and a literature review

Some of the immunologic mechanisms involved in malaria physiopathology remain unclear. In animals, the spleen seems to play a key role in protecting the host against malaria. However, little is known about the effect of spleen dysfunction on human malaria. We report two severe cases of Plasmodium falciparum infection with unusual clinical and parasitologic features in two splenectomized men living in French Guiana. The peripheral blood of these cases showed hyperparasitemia, with a high proportion of mature parasites and leukocytes with malaria pigment. Despite appropriate treatment and adequate absorption, hyperparasitemia persisted. Parasite clearance was delayed and one patient died. Only the patient who died had the merozoite surface protein 1 allele B-K1 and the varD gene genotype, which is considered to be a probable parasite virulence factor. These uncommon cases differ from most of those described in the literature, illustrating the complexity of the mechanisms underlying the protective function of the spleen in human malaria.