In vitro assessment of a collagen sponge for engineering urothelial grafts

OBJECTIVE: To investigate the deposition of urinary crystals and the growth characteristics of urothelial cells on a collagen sponge, as a preliminary step in engineering urothelial autologous grafts. MATERIALS AND METHODS: Collagen sponges were exposed to a continuous flow of urine at pH 5.3 and 6.3 for 1 week. The sponges were examined microscopically for crystal deposition and analysed for their calcium content. Two cell lines, RT112, derived from a well-differentiated transitional cell carcinoma, and UROtsa, an immortalized urothelial cell line, were seeded on the collagen sponges. Cells were cultured for 6, 12 and 21 days. The pattern of growth was analysed by histology and immunostaining with a pan-cytokeratin antibody. Growth was assayed to quantify cell proliferation on the sponges. RESULTS: No crystals were evident on any of the collagen sponges. Calcium deposition was negligible at pH 5.3. Although calcium levels were measurable at pH 6.3, the levels were very low. Both cell lines attached and grew in a stratified manner on the collagen sponge, RT112 forming a layer 6-8 cells thick, and UROtsa a layer 4-6 cells thick; cell proliferation was maximal at 5-10 days. The sponge remained easy to handle after 3 weeks in culture. CONCLUSION: These findings show that collagen sponges support the growth and stratification of urothelial cells, and indicate that the collagen sponge is a suitable substrate for developing urothelial autologous grafts.     

Health assessment in the rheumatic diseases of childhood

Assessment of children and adults with rheumatic diseases, both in clinical practice and controlled clinical trials in rheumatology, has traditionally focused on the measurement of disease activity. More recently emphasis has been placed on the need to incorporate estimates of physical, social, and mental functioning into health assessment. Thus there has been a tremendous growth in the development of measurement instruments that evaluate health status, functional status, disability, and quality of life. This type of measurement has become essential, particularly for clinical trials in adults with rheumatic diseases, for which the AIMS (Arthritis Impact Measurement Scales), the HAQ (Health Assessment Questionnaire), and the MACTAR (McMaster-Toronto arthritis) patient preference questionnaire have been the most widely used. In the past few years, similar measures have been developed for application in children with rheumatic diseases. These include the CHAIMS (Childhood Arthritis Impact Measurement Scales), the CHAQ (Childhood Health Assessment Questionnaire), the JAFAR (Juvenile Arthritis Functional Assessment Report), the JASI (Juvenile Arthritis Self-report Index), the JAQQ (Juvenile Arthritis Quality of Life Questionnaire), and the CAHP (Childhood Arthritis Health Profile). In this review, the development and measurement properties of these childhood instruments are discussed, with particular emphasis on their potential roles as supported by recent literature.     

Polyterthiophenes as Donors for Polymer Solar Cells

Thiophene‐containing polymers blended with fullerenes have recently demonstrated impressively high photovoltaic efficiencies. One drawback of this class of polymers is their relatively low ionization potential, which leads to rather low open‐circuit voltages. Polyterthiophenes belong to a material class that has recently captured a large amount of interest for polymer electronic applications because of its excellent transport properties. Because of the slightly lower ionization potential, this material class appears more attractive for photovoltaic applications than polythiophenes. In this work, the photovoltaic performance of bulk heterojunction solar cells from polyterthiophene/fullerene composites is discussed and compared to the polymer/fullerene blend morphology.     

Positive affectivity and negative outcomes: the role of tenure and job satisfaction

In this study, the authors proposed and tested a 3-way interaction among positive affectivity (PA), job satisfaction, and tenure in predicting negative employee outcomes. Specifically, the authors predicted that the relationship between job satisfaction and negative outcomes would be stronger for high PAs and that this relationship would be more pronounced for longer tenured employees. Results support this 3-way interaction in predicting job search behavior, physical health complaints, and counterproductive employee behavior. In particular, the relationship between job satisfaction and negative outcomes was most strongly negative for high-PA individuals with longer tenure. The authors discuss the implications of these results and some directions for future research.     

The design and evaluation of online help for Unix EMACS: capturingthe user in menu design

The card-sort technique and cluster analysis were used for determining an effective organization for a help menu in Unix EMACS. Similarity data were gathered for with a card-sorting task using EMACS commands, and a hierarchical cluster analysis of the data was performed. The results indicate that differences among novices, intermediates, and experts appear with computer-based concepts such as windows and buffers, but that the sorts are more similar than they are different. It is argued that cluster analysis may aid designers in determining a functional organization, but that in the domain of this study, this organization may not help users bridge the mapping from real world tasks to computer tasks     

Electrochemical behaviour and glass formation in molten bisulphates

Molten bisulphates form an interesting class of low-temperature fused salts which quench to form glasses; some technical and theoretical applications of these systems are discussed. The NaHSO₄KHSO-₄ eutectic (46.5% KHSO₄, m.p. 125°C,T _g 25°C) is easy to study since at lower temperatures decomposition of the melt is retarded and supercooling readily occurs. The solvent properties of this eutectic towards both inorganic and organic solutes have been investigated. The oxidation states available to transition and post-transition metals were studied spectrophotometrically and voltametrically; the results show a very restricted pattern of redox chemistry. The (abbreviated) electrochemical series is V(V)/V(IV)>Mn(III)/Mn(II)>H(I)/H₂(O)>Ag(I)/Ag(O)>Mo(VI)/Mo(V)> Hg(I)/Hg(O)>Cu(II)/Cu(O)>Zn(II)/Zn(O). The Hammett acidity function,H ₀, was measured as in the range –1 to –2. Various factors influencing redox reactions in the melt are discussed.     

Smoking abstinence, eating style, and food intake.

Individual differences in weight gain after smoking cessation may reflect differences in eating restraint that exist before cessation. It was hypothesized that abstinent smokers with high scores on the Eating Inventory Disinhibition Scale would be more likely to overeat than nonabstinent smokers with lower Disinhibition Scale scores. Forty smokers completed the Eating Inventory and the Profile of Mood States (POMS). Subjects were randomly assigned to 24-hr cigarette abstinence or to continued smoking. Subjects then participated in an ice cream tasting task, after which they were free to eat as much ice cream as they wanted. The hypothesis was confirmed. Exploratory analyses indicated that eating behavior items predicted the amount eaten and that weight fluctuation items did not. The POMS Confusion Scale scores were highest for abstinent subjects who scored high on the Disinhibition Scale. A parallel but nonsignificant relation was observed for POMS Tension Scale scores. The meaning of these data for the relation between smoking cessation and weight gain is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)