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Background Cardiac tissue engineering might be useful in treatment of diseased myocardium or cardiac malformations. The creation of functional, biocompatible contractile tissues, however, remains challenging. We hypothesized that coupling of arginine-glycine-aspartic acid-serine (RGD+) adhesion peptides would improve cardiomyocyte viability and differentiation and contractile performance of collagen-cell scaffolds. Methods Clinically approved collagen scaffolds were functionalized with RGD+ cells and seeded with cardiomyocytes. Contractile performance, cardiomyocyte viability and differentiation were analyzed at days 1 and 8 and/or after culture for 1 month. Results The method used for the RGD+ cell-collagen scaffold coupling enabled the following features: high coupling yields and complete washout of excess reagent and by-products with no need for chromatography; spectroscopic quantification of RGD+ coupling; a spacer arm of 36 Å, a length reported as optimal for RGD+-peptide presentation and favorable for integrin-receptor clustering and subsequent activation. Isotonic and isometric mechanical parameters, either spontaneous or electrostimulated, exhibited good performance in RGD+ constructs. Cell number and viability was increased in RGD+ scaffolds, and we saw good organization of cell contractile apparatus with occurrence of cross-striation. Conclusions We report a novel method of engineering a highly effective collagen-cell scaffold based on RGD+ peptides cross-linked to a clinically approved collagen matrix. The main advantages were cell contractile performance, cardiomyocyte viability and differentiation. [ABSTRACT FROM AUTHOR]

Objective: To determine the psychometric properties of the recently developed German version of the Multidimensional Quality of Life Questionnaire for HIV/AIDS (MQOL-HIV) and to test its performance in a sample of HIV-infected patients.Methods: Two-hundred and seven outpatients with HIV/AIDS were interviewed with the German version of the MQOL-HIV; 109 patients were interviewed a second time approximately 2 weeks later. Patients also completed the Beck Depression Inventory (BDI) and the World Health Organization Disability Assessment Schedule II (WHODAS II).Results: The German version of the MQOL-HIV showed satisfactory internal consistency (r: 0.74-0.85, sexual functioning: r = 0.61) and test-retest reliability in most subscales (r: 0.74-0.89, medical care: r = 0.67). Convergent validity with WHO-DAS II and BDI was satisfactory for most domains. Exploratory factor analysis yielded a seven-factor solution with separate factors for physical, emotional, cognitive, social and financial aspects, sexual functioning and medical care. CD4 count and source of infection were associated with most QOL domains, whereas age and gender showed no major impact on QOL. High rates of missing values were seen in the partnership domain and substantial ceiling effects in the area of medical care.Conclusions: Overall the German version of the MQOL-HIV showed satisfactory reliability and validity. However, the domains of partnership, sexuality and medical care should generally receive more emphasis in future research on QOL assessment in patients with HIV/AIDS and the MQOL-HIV may be improved in these domains. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the incidence of catamenial pneumothorax (CP) among women who have been referred for the surgical treatment of spontaneous pneumothorax (SP) and to study its pathogenic mechanisms.Design: A prospective study of women of reproductive age who have been referred to our center for the surgical treatment of SP. Patients with pneumothorax secondary to a known lung disease were excluded.Setting: A university hospital.Methods: At the preoperative evaluation, special attention was given to the investigation of a possible temporal relationship between pneumothorax and menses. Video-assisted thoracoscopy constituted the operative technique of choice. The lung was inspected to identify blebs or bullae and the origin of possible air leaks. Signs of thoracic endometriosis were also carefully searched for. The diaphragm was systematically inspected to search for holes and/or endometrial implants. When limited diaphragmatic abnormalities were found, a partial diaphragmatic resection was carried out using an endoscopic stapler. In case of lesions that were not accessible by a purely endoscopic approach, a utility minithoracotomy was used.Results: In an 18-month period, 32 women with SP were referred for surgery. In eight cases, the catamenial character of the pneumothorax was recognized by clinical history. In all these patients, the following diaphragmatic abnormalities were found at surgery: holes (one patient); endometrial implants (three patients); and both (four patients). Visceral pleural endometriosis was found in one patient. During pathologic examination, diaphragmatic endometriosis was confirmed in seven of the eight cases. In one patient, it was associated with pulmonary and pleural endometriosis. In only one patient (with multiple diaphragmatic holes and a pulmonary nodular brown lesion), endometriosis could not be confirmed at histology, but signs of parenchymal focal hemorrhages were found.Conclusions: Our experience shows that (1) CP is more frequent than expected and (2) diaphragmatic abnormalities seem to play a fundamental role in its pathogenesis. [ABSTRACT FROM AUTHOR]

Xenotransplantation between discordant species leads to a hyperacute rejection mediated by natural antibodies. both of the IgG and IgM isotypes, activation of complement and endothelial cell activation. The combination of these mechanisms leads to a transplant survival of minutes to a few hours. Polyclonal human irnmunoglobulins for intravenous use ([V]g) from normal donors have proved effective in a number of antibody-mediated disorders, as well as in inflammatory disorders. We demonstrate that administration of [V]g in a guinea pig to rat model of cardiac xenografting can effectively delay hyperacute rejection. This effect is mediated by the F(ab')2 fragments of [V]g. and is correlated to an anti-complementary activity. [ABSTRACT FROM AUTHOR]