Análisis de la cohesión y la conducta percibida en jugadores profesionales balonmano / Analysis of cohesion and perceived behavior in professional handball players

The objective of this study was to analyse the correlation between perceived leadership behaviours of the Multidimensional Leadership Model (MML) and the cohesion categories of the Carron Cohesion Model in professional handball players. The sample was composed by 112 players who answered the Leadership Scale for Sport (LSS2) and the Group Environment Questionnaire (GEQ) questionnaires. The results obtained (r = from 0.307 to 0.634) show an association between the cohesion variable (ATG-T) and the perceived behaviours of the (MML). A cohesion tendency towards the task by the players is observed. Autocratic behaviour exceeds democratic behaviour and training and instruction behaviours obtain the highest values. We conclude that cohesion towards the task is predominant in high performance players and that the high demand of the category demands different behaviours from the coach. (AU)

El objetivo del presente estudio fue analizar la correlación entre las conductas del liderazgo percibido del Modelo Multidimensional de Liderazgo (MML) y las categorías de cohesión del Modelo de Cohesión de Carron en jugadores profesionales de balonmano. La muestra estuvo compuesta por un total de 112 jugadores a los cuales se les administró los cuestionarios Leadership Scale for Sport (LSS2) y el Group Environment Questionaaire (GEQ). Los resultados obtenidos (r = de 0.307 -0.634)muestran una asociación entre la variable de cohesión (ATG-T) y las conductas percibidas del (MML). Se observa una tendencia de cohesión hacia la tarea por parte de los jugadores. La conducta autocrática supera la democrática y la de entrenamiento e instrucción obtiene los valores más elevados. Concluimos que la cohesión hacia la tarea es la predominante en jugadores de alto rendimiento y que la alta exigencia de la categoría demanda de diferentes conductas del entrenador. (AU)

Longitudinal retention of families in the assessment of a prevention program targeting adolescent alcohol and tobacco use: the utility of an ecological systems framework.

This study examined the association between ecological context (extrafamilial, familial, child factors) at baseline and longitudinal retention of families in the 36-month assessment of an adolescent alcohol and tobacco use prevention program that was conducted within a pediatric primary care setting. A total of 1,780 families were enrolled at baseline when the youth were in the fifth and sixth grades, and 1,220 of these families participated in the 36-month assessment. Findings indicated that familial and child, but not extrafamilial, factors were associated with the participation of families in the 36-month assessment. Clinical implications and future research directions are discussed.

Análisis de las conductas de liderazgo en jugadores profesionales de balonmano / Analysis Leadership Behaviours in Professional Handball Players

Los objetivos del presente estudio fueron analizar las diferencias entre las autopercepciones de las conductas de liderazgo preferido y percibido en jugadores de balonmano de élite en dos momentos diferenciados de la temporada. Paralelamente analizar las modificaciones existentes en las conductas en el transcurso de un periodo competitivo. La muestra estuvo compuesta por un total de 71 jugadores profesionales a los cuales se les administraron los cuestionarios Leadership Scale for Sport (LSS1 y LSS2). Los resultados mostraron diferencias significativas entre la conducta preferida y percibida en todas las conductas estudiadas a excepción de la democrática en los dos momentos observados de la temporada y por otro lado se observaron diferencias significativas entre la conducta preferida (pre-post) y la percibida (pre-post) en todas las conductas estudiadas. Concluimos que las autopercepciones de los jugadores sobre su entrenador difieren entre lo que prefieren y lo que perciben a lo largo de la temporada. (AU)

The aim of the study was to analyze the differences between the self-perceptions of preferred and perceived leadership behaviors in elite handball players at two different moments of the season and, in parallel, to analyze the existing modifications in the two behaviors during a competitive period. The sample was composed by 71 professional ASOBAL league players who answered the Leadership Scale for Sport questionnaires (LSS1 and LSS2). The results showed significant differences between the preferred and perceived behavior in all the studied behaviors except for the democratic one (preseason) in the two observed moments of the season and, on the other hand, significant differences were observed between the preferred behavior (pre-post) and the perceived (pre-post) in all the studied behaviors. We conclude that the players' self-perceptions of their coach differ between what they prefer and what they perceive throughout the season. (AU)

Flow cytometric analysis of coronary stent-induced alterations of platelet antigens in an in vitro model.

One of the limitations of coronary stenting is the subacute thrombotic occlusion. In an in vitro model, we examined the effects of tantalum wire stents (n = 12) on platelet antigens. Platelet-rich plasma (PRP) was circulated in PVC tubing systems. At fixed intervals over a 10-min time course, aliquots of PRP were drawn, stained with monoclonal antibodies (CD41a, CD42b, CD62p, and CD63), and analyzed by flow cytometry. Within 2 minutes of the onset of circulation, expression of the activation-dependent antigens CD62p and CD63 increased in all tubing systems with stents. This early increase was followed by a progressive rise in fluorescence intensity of these neoantigens over the course of 10 minutes (p < 0.05 vs.. control system without stent). Antigens CD41a and CD42b did not show significant changes in either system. The artificial surfaces and shear forces of stent meshes induce alterations in platelet antigens. Flow cytometry provides a sensitive technique for in vitro testing of the thrombogenicity of coronary stents, and may be useful in further improving stent biocompatibility.

In vitro analyses of diamond-like carbon coated stents. Reduction of metal ion release, platelet activation, and thrombogenicity.

Coronary artery stents can induce platelet activation by shear forces, contact to the biomaterial, and release of metal ions. This activation is one important trigger for thrombosis. Coating of stents is a possible approach to prevent this side effect. The purpose of this study was to evaluate in vitro the biocompatibility of stents coated with diamond-like carbon (DLC). Semiquantitative energy-dispersive X-ray microanalyses showed a complete coverage of the DLC stents. Flow cytometric analyses revealed a significantly higher increase of mean channel fluorescence intensity for the activation-dependent antigens CD62p and CD63 in non-coated compared to DLC-coated stents (p<0.05). Atomic adsorption spectrophotometry analyses revealed a significant release of nickel and chromium metal ions by non-coated stents over a storage period of 96 hours in human plasma (p<0.05). In contrast, only minimal concentrations of released ions could be detected in the case of DLC-coated stents. Similar observations were made with inductively coupled plasma mass spectrometry analyses. Here, high concentrations of molybdenum and manganese ions were released from non-coated stents (p<0.05), while release of these ions from DLC-coated stents was virtually undetectable (p=0.1 for molybdenum and p=0.4 for manganese). Coating of intracoronary stents with diamond-like carbon significantly improves biocompatibility. This biocompatible coating may therefore contribute to a reduction in thrombogenicity.

Influence of stent length and heparin coating on platelet activation: a flow cytometric analysis in a pulsed floating model.

Platelets are involved in acute and subacute thrombotic occlusions of coronary stents and also may play a role in the pathophysiology of in-stent restenosis. This study sought to investigate the expression of activation dependent glycoproteins on platelets by flow cytometry and time until stent thrombosis in an in vitro model of stent thrombosis. Coronary stents were placed in parallel silicon tubings with circulating citrated platelet rich plasma to measure 1) influence of stent length on platelet antigens; 2) influence of heparin coating on platelet antigens; and 3) time until stent thrombosis. After recalcification aliquots of platelet-rich plasma were taken over 10 minutes in 2-minute intervals and immediately fixed and stabilized. For flow cytometric analysis monoclonal antibodies to CD41a (glycoprotein IIb/ IIIa), CD42b (glycoprotein Ib-V-IX), CD62p (P-selectin), and CD63 (glycoprotein 53) were used. Within 2 minutes after start of circulation, the expression of CD62p and CD63 increased. Longer stents resulted in more platelet activation than shorter stents (25 mm vs. 15 mm; p<0.001. Time until stent thrombosis was reduced (25 mm vs. 15 mm; p<0.05). Heparin coating did not significantly influence flow cytometry detectable platelet activation but prolonged time until stent thrombosis (coated vs. uncoated; p<0.005). In control tubing systems without stents platelet activation was less pronounced (p<0.0001). Antibodies to CD41a and CD42b did not show significant changes. In this model platelet activation detected by flow cytometry and time until stent thrombosis were dependent on stent length and coating. In vitro testing could be useful to optimize stent design and material.

Influence of spleen meridian herbs on the harmonic spectrum of the arterial pulse.

Pulse analysis is a powerful method in Chinese medicine. We suggest that the effect of herbal medicine is to redistribute the blood to organs and meridians. In this report, by injecting extracts into rats and then analyzing the blood pressure wave measured at the caudate arteries, we studied eight important spleen meridian related herbs: They were Semen Lablab, Fructus Amomi Globosi, Rhizoma Atractylodis Macrocephalae, Rhizoma Atractylodis, Tuber Pinelliae, Radix Codonopsitis, Pericarpium Aurantii and Rhizoma Polygonati. All eight herbs increased the intensity of the 3rd harmonic (C3) of the pressure pulse which is correlated to the spleen and spleen meridian, as described in traditional Chinese medical literature. All of them also increased the 2nd harmonic (which is correlated to the kidney and the kidney meridian) as well as decreased the heart load (DC term of pressure wave, C0). Tuber Pinelliae, Radix Codonopsitis, Pericarpium Aurantii and Rhizoma Polygonati decreased the 1st harmonic (correlated to the liver meridian) significantly, while Rhizoma Atractylodis Macrocephalae only decreased C1 slightly. Except for Semen Lablab, all the others decreased the intensity of the 5th (stomach meridian) and the 7th harmonics. The effects of kidney herbs: Cortex Eucommiae and Radix Achyranthis were also shown for comparison.

[Primary lymphoma of the central nervous system in a patient with AIDS]. / Linfoma primitivo do sistema nervoso central em doente com SIDA.

The increasing incidence of primary brain lymphoma appears to be real in immunologically normal people. However, lymphoma of the central nervous system has a much higher incidence in patients with immune deficient status as in renal and cardiac transplants, patients with IgA deficiency, or Wiskott-Aldrich syndrome. Thus, the increased predisposition of AIDS patients to brain lymphoma is not surprising, this being the second most frequent cause among cerebral mass lesions in the AIDS population. We report a case of a 36 year old white woman with AIDS and a cerebral mass lesion which we demonstrated to be a primary brain lymphoma.

[Adenocarcinoma of the colon disclosed by endocarditis caused by Streptococcus bovis]. / Adenocarcinoma do colon revelado por endocardite por estreptococos bovis.

The association of Streptococcus bovis endocarditis with colonic neoplasms has been well documented. We describe a patient in whom the finding of a Str. bovis endocarditis stimulated investigation which resulted in the diagnosis and surgical treatment of an adenocarcinoma of the colon.

Family socialization of adolescent's self-reported cigarette use: the role of parents' history of regular smoking and parenting style.

OBJECTIVE: To examine the main and interactive effects of parental history of regular cigarette smoking and parenting style on adolescent self-reported cigarette use. METHODS: Predictors of adolescent self-reported cigarette use, including parents' history of regular cigarette smoking and two dimensions of parenting behavior, were analyzed in a sample of 934 predominately Caucasian (96.3%) parent-adolescent dyads. Families were drawn from the control group of a randomized control trial aimed at preventing adolescent substance use. RESULTS: In addition to the main effects of parents' history of regular smoking and parental warmth, logistic regression analysis revealed that the interaction of these two variables was associated with adolescent self-reported cigarette use. Parental warmth was associated with a decreased likelihood of the adolescent ever having smoked a cigarette; however, this was true only if neither parent had a history of regular cigarette smoking. CONCLUSIONS: Findings suggest that adolescent smoking prevention programs may be more efficacious if they address both parental history of regular smoking and parenting behavior.

Hereditary alpha1--antitrypsin deficiency associated with congenital extrahepatic bile duct hypoplasia.

A child, two months of age, suffering from cholestasis and biliary cirrhosis, was found to be homozygous for alpha1-antitrypsin deficiency Pi type ZZ associated with high degree extrahepatic bile duct obstruction. The clinical, protein-chemical, genetic, histological and immuno-histochemical findings in the patient are reported and the relationships between these two anomalies interpreted. An interaction between the very rare defects rather than random association is suggested.

Interparental conflict and relations with parents as predictors of young adult functioning.

Interparental conflict is a known risk factor for child adjustment problems; yet few studies have examined its long-term effects. This study tests the following hypotheses: Interparental conflict has both longitudinal and concurrent influences on the functioning of young adult children, and the relationship between young adults and their parents mediates these influences. We assessed a community sample (N = 243) of families when the target child was in early to middle adolescence. We then reassessed them 6 years later during young adulthood. The links of interparental conflict measured at the two time points to young adults' general psychopathology and antisocial behavior were examined using multiple regression analyses. The quality of the relationship between young adults and each parent was added to each equation as a potential mediating variable. Results showed that concurrent, but not earlier, interparental conflict predicted males' antisocial behavior. No support was found for the mediational model, but support was found for an alternate model positing direct effects for interparental conflict and the parent-young adult relationship on young adult functioning. For females and males, problematic relationships with mothers and father predicted greater general psychopathology, while problems in paternal relationships predicted higher levels of antisocial behavior only for females.

Pheromone-triggered orientation flight of male moths can be disrupted by trifluoromethyl ketones.

In a wind tunnel trifluoromethyl ketones (TFMKs) have been found to disrupt the orientation flight of male moths to pheromone sources (virgin females or synthetic pheromone). This is demonstrated by comparison of the flight parameters of the Egyptian armyworm Spodoptera littoralis and the Mediterranean corn borer Sesamia nonagrioides, which had been topically treated with TFMKs, with those calculated for untreated insects. Inhibition occurred in all types of behavior and that of the source contact has been quantified and found to be dose-dependent. The same effect has also been noticed in Mediterranean corn borer males flying to an attraction source consisting of mixtures of (Z)-11-hexadecenyl trifluoromethyl ketone (8), a closely related analogue of the major component of the pheromone, and the natural pheromone blend. The most active TFMKs are those closest in structure to the natural pheromone, along with those chemicals which easily hydrate in solution, such as the beta-thiosubstituted derivatives. Along with the previously reported reduction of catches in the field, our results suggest the possible application of these chemicals in future new pest control strategies.

Tantalum stents induce expression of GMP140 and GP53 on platelets after contact in an in vitro model.

Endovascular implantation of stents has become increasingly important to reduce acute complications and restenosis after percutaneous transluminal coronary angioplasty (PTCA). Nevertheless, the risk of stent related thrombosis still appears to be a limitation in this therapeutic approach. As platelets play a major role in thrombus formation, we examined platelets in an in vitro model by flow cytometry to assess the expression of activation-dependent epitopes caused by shear stress and contact to artificial surfaces of stents. Tantalum wire stents (n = 12) were placed in one of two parallel silicon tubing systems. Both systems were filled with citrated platelet-rich plasma (PRP) of healthy and drug-free volunteers. After recalcification, aliquots of PRP were drawn via a three-way faucet over a course of 10 min. For flow cytometric analysis monoclonal antibodies CD41a, CD42b, CD62p and CD63 were applied. Within 2 min after onset, the expression of CD62p (GMP140) and CD63 (GP53) increased in the tubing system with the stent. Over the course of 10 min, platelet activation progressively increased (CD62p p < 0.05 vs. control system without stent; CD63 p < 0.005 vs. control). Antigens CD41 a and CD42b did not show significant changes in both systems. Artificial surfaces and shear forces of stent meshes may contribute to the activation of platelets, thereby promoting the thrombotic potential. As an utmost sensitive diagnostic tool, flow cytometry may attribute to further improvement of material and design of stents.

[Flow-cytometric analysis of platelet activation during rotablation]. / Durchflusszytometrisch nachgewiesene Aktivierung von Thrombozyten im Verlauf der Rotablation.

Acute occlusion and subacute restenosis of the coronary artery are still the limiting factors of the otherwise successful interventional cardiology. Platelets and especially activated platelet populations play a key role concerning these typical and sometimes fatal complications. In this study we used flow-cytometry to determine the influence of the modern interventional technique of rotablation on platelet antigens and their possible alteration. A PTCA control group was included. We analyzed the fluorescence expression of structural antigens CD41a (GPII-IIIa) and CD42b (GPIb-V-IX), and of the activation-dependent antigens CD62p (P-selectin, PADGEM, GMP-140) and CD63 (GP53). Furthermore we analyzed the binding of fibrinogen to the platelet flow-cytometrically. CD41a and CD42b did not show significant alternations in fluorescence before, directly after and thirty minutes after finishing PTCA and rotablation (PTCA: CD41a p=0.8 and 0.9; CD42b p=0.5 and 0.2; rotablation: CD41a p=0.2 and 0.2; CD42b p=0.4 and 0.1). But platelet activation could be detected directly after PTCA and rotablation measuring the mean channel fluorescence intensity (MCFI) of CD62p, CD63 and fibrinogen binding (all p<0.05). Thirty minutes after finishing the procedures there were again significant changes in MCFI in PTCA (CD62p, CD63, fibrinogen binding; all p<0.05), but not in rotablation (CD62p p=0.1; CD63 p=0. 9; fibrinogen binding p=0.5). But MCFI for CD62p and fibrinogen binding in rotablation was higher than in PTCA. The results of our study show that rotablation also induces significant platelet activation that is higher than in PTCA alone. Flow cytometry is a sensitive and specific, multiparametric tool in establishing platelet activation. The individual platelet activation process is part of a complex cascade of events happening in the rotablated coronary segment leading to a vascular-molecular inflammatory process and consecutive clinical problems in some patients.

Altered mechanics and histomorphometry of canine tibial cartilage following joint immobilization.

Joint immobilization is associated with altered cartilage biosynthesis and catabolism that may affect cartilage mechanics and joint function. In this study, the mechanical behavior of articular cartilage was studied in an experimental model of joint immobilization, in which the canine knee was cast-immobilized at 90 degrees of flexion for 4 weeks. Articular cartilage from the medial tibial plateau was tested in compression and in shear. Biochemical assays for water and glycosaminoglycan content and histomorphometric grading were performed on site-matched samples. Significant decreases in the equilibrium and dynamic shear moduli, but not compressive moduli, were observed in cartilage after 4 weeks of joint immobilization as compared to cartilage from a separate control population. Importantly, there was also evidence of a decrease in the compressive and shear moduli of tibial cartilage from the contralateral knee joints compared to control joints that were not immobilized. No significant effect of immobilization on the biochemical parameters or histomorphometric scores was detected, expect for a significant loss of proteoglycan staining following immobilization. These findings for changes in the tibial cartilage following cast immobilization are consistent with a mild form of cartilage degeneration.

Comparative studies of female sex pheromone components and male response of the corn stalk borer Sesamia nonagrioides in three different populations.

Studies to determine possible differences in the pheromone communication system of three different populations of the corn stalk borer Sesamia nonagrioides (Lef.) in France. Spain. and Greece were carried out. The two main pheromone components (Z)-11-hexadecenyl acetate (Z11-16:Ac) and (Z)-11-hexadecenol (Z11-16:OH), were detected in all analyses with very small differences in the three populations. Among the minor components, analyzed by GC-MS on concentrated gland extracts from French and Greek origin females, (Z)-l1-hexadecenal (Z11-16:Ald) was detected in minor amounts. Wind-tunnel and field studies revealed similar a male response in the three populations to pheromone glands extracts and synthetic pheromone regardless of the female/male origin. The results do not support the assumption of the existence of different pheromone types of the corn stalk borer S. nonagrioides due to geographic isolation.