131 research outputs found
Health region development from the perspective of system theory - An empirical cross-regional case study
Governments are increasingly establishing health regions to deal with current challenges of public health service. These regions are seen as instruments to balance public and private stakeholders, and offer health care to regional citizens as well as to medical/health tourists. However, it is still unclear how the development of such health regions as well as their governance may be conceptualized. We apply Luhmann's system theory approach in the context of a cross-regional case study that compares health region developments in the Autonomous Province of Bolzano-South Tyrol (Italy) with particular regard to the Eastern Dolomites and in the province of Zeeland (the Netherlands). We suggest that Luhmann's system theory provides a useful set of criteria to evaluate and judge health region development. Fully developed health regions can be understood as auto-poietic systems. By emphasizing programs, personnel, and communication channels, these case studies illustrate the suitability of the system theory toolset to analyze the governance and spatial embeddedness of health regions. Additionally, the study contributes to literature by indicating that health regions are closely related to identity issues and to decision making in regions
Spontaner und posttherapeutischer Knorpelrepair: Bewertungskriterien
Zusammenfassung: Der für das Funktionieren der großen Gelenke entscheidende Gelenkknorpel besitzt beim Erwachsenen praktische keine Reparaturkapazität, weshalb einmal entstandene Schäden chronisch erhalten bleiben und sich zumeist sogar ausbreiten und in eine Osteoarthrose überzugehen drohen. Seit einem Jahrzehnt sind verschiedene neue und innovative Therapien entwickelt worden, um Regenerate zu implantieren oder intraartikulär zu induzieren und deren Funktionalität und Belastbarkeit zu erhöhen. Ein wesentlicher Parameter zur Erfassung der Funktionalität der erzeugten Regenerate ist hierbei das morphologisch erfassbare Bild, da dieses im Moment am ehesten erlaubt, Vorraussagen über die Funktionalität und Haltbarkeit der Regenerate zu treffen. Um die vielerorts laufenden Studien international vergleichend auswertbar zu machen, wurde eine Konsensusbeurteilungsskala durch die ICRS (International Cartilage Repair Society) kürzlich veröffentlicht, welche in diesem Übersichtsartikel vorgestellt und erläutert wir
Pengaruh Beban Pendinginan terhadap Temperatur Sistem Residential Air Conditioning Hibrida dengan Kondensor Dummy Tipe Trombone Coil Menggunakan Refrigeran Hidrokarbon
An experimental study in the hybrid air conditioning machine as air conditioner and water heater by retrofitting R-22 with hydrocarbon refrigerant (HCR-22) have been investigated. Drop-in experiments were carried out without any modification on the system. The system has been tested by varying the internal heat load 0, 1000, 2000, and 3000 W for residential cooling load simulation. The measurements taken during two hour experimental periods at 5 minutes interval times for temperature set point of 19°C. Temperature of the system is the objective of this research. The result shows refrigerant temperature of HCR-22 lower than R-22 because differences of compressor discharge pressure. Temperature discharge decrease between 16.22-24.02 ˚C. For conditioned room, room temperature in every internal heat load was relative same. And water temperature in 50 L storage are 46.58-48.81 ˚C
Augmentation of osteochondral repair with hyperbaric oxygenation: a rabbit study
<p>Abstract</p> <p>Background</p> <p>Current treatments for osteochondral injuries often result in suboptimal healing. We hypothesized that the combination of hyperbaric oxygen (HBO) and fibrin would be superior to either method alone in treating full-thickness osteochondral defects.</p> <p>Methods</p> <p>Osteochondral repair was evaluated in 4 treatment groups (control, fibrin, HBO, and HBO+fibrin groups) at 2-12 weeks after surgical injury. Forty adult male New Zealand white rabbits underwent arthrotomy and osteochondral surgery on both knees. Two osteochondral defects were created in each femoral condyle, one in a weight-bearing area and the other in a non-weight-bearing area. An exogenous fibrin clot was placed in each defect in the right knee. Left knee defects were left empty. Half of the rabbits then underwent hyperbaric oxygen therapy. The defects in the 4 treatment groups were then examined histologically at 2, 4, 6, 8, and 12 weeks after surgery.</p> <p>Results</p> <p>The HBO+fibrin group showed more rapid and more uniform repair than the control and fibrin only groups, but was not significantly different from the group receiving HBO alone. In the 2 HBO groups, organized repair and good integration with adjacent cartilage were seen at 8 weeks; complete regeneration was observed at 12 weeks.</p> <p>Conclusions</p> <p>HBO significantly accelerated the repair of osteochondral defects in this rabbit model; however, the addition of fibrin produced no further improvement.</p
Survival of Chondrocytes in Rabbit Septal Cartilage After Electromechanical Reshaping
Electromechanical reshaping (EMR) has been recently described as an alternative method for reshaping facial cartilage without the need for incisions or sutures. This study focuses on determining the short- and long-term viability of chondrocytes following EMR in cartilage grafts maintained in tissue culture. Flat rabbit nasal septal cartilage specimens were bent into semi-cylindrical shapes by an aluminum jig while a constant electric voltage was applied across the concave and convex surfaces. After EMR, specimens were maintained in culture media for 64 days. Over this time period, specimens were serially biopsied and then stained with a fluorescent live–dead assay system and imaged using laser scanning confocal microscopy. In addition, the fraction of viable chondrocytes was measured, correlated with voltage, voltage application time, electric field configuration, and examined serially. The fraction of viable chondrocytes decreased with voltage and application time. High local electric field intensity and proximity to the positive electrode also focally reduced chondrocyte viability. The density of viable chondrocytes decreased over time and reached a steady state after 2–4 weeks. Viable cells were concentrated within the central region of the specimen. Approximately 20% of original chondrocytes remained viable after reshaping with optimal voltage and application time parameters and compared favorably with conventional surgical shape change techniques such as morselization
Time evolution of in vivo articular cartilage repair induced by bone marrow stimulation and scaffold implantation in rabbits
Purpose: Tissue engineering techniques were used to study cartilage repair over a 12-month period in a rabbit model.
Methods: A full-depth chondral defect along with subchondral bone injury were originated in the knee joint, where a biostable porous scaffold was implanted, synthesized of poly(ethyl acrylate-co-hydroxyethyl acrylate) copolymer. Morphological evolution of cartilage repair was studied 1 and 2 weeks, and 1, 3, and 12 months after implantation by histological techniques. The 3-month group was chosen to compare cartilage repair to an additional group where scaffolds were preseeded with allogeneic chondrocytes before implantation, and also to controls, who underwent the same surgery procedure, with no scaffold implantation.
Results: Neotissue growth was first observed in the deepest scaffold pores 1 week after implantation, which spread thereafter; 3 months later scaffold pores were filled mostly with cartilaginous tissue in superficial and middle zones, and with bone tissue adjacent to subchondral bone. Simultaneously, native chondrocytes at the edges of the defect started to proliferate 1 week after implantation; within a month those edges had grown centripetally and seemed to embed the scaffold, and after 3 months, hyaline-like cartilage was observed on the condylar surface. Preseeded scaffolds slightly improved tissue growth, although the quality of repair tissue was similar to non-preseeded scaffolds. Controls showed that fibrous cartilage was mainly filling the repair area 3 months after surgery. In the 12-month group, articular cartilage resembled the untreated surface.
Conclusions: Scaffolds guided cartilaginous tissue growth in vivo, suggesting their importance in stress transmission to the cells for cartilage repair.This study was supported by the Spanish Ministry of Science and Innovation through MAT2010-21611-C03-00 project (including the FEDER financial support), by Conselleria de Educacion (Generalitat Valenciana, Spain) PROMETEO/2011/084 grant, and by CIBER-BBN en Bioingenieria, Biomateriales y Nanomedicina. The work of JLGR was partially supported by funds from the Generalitat Valenciana, ACOMP/2012/075 project. CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the - Instituto de Salud Carlos III with assistance from the European Regional Development Fund.Sancho-Tello Valls, M.; Forriol, F.; Gastaldi, P.; Ruiz Sauri, A.; Martín De Llano, JJ.; Novella-Maestre, E.; Antolinos Turpín, CM.... (2015). 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Mainstreams of Horizontal Gene Exchange in Enterobacteria: Consideration of the Outbreak of Enterohemorrhagic E. coli O104:H4 in Germany in 2011
Escherichia coli O104:H4 caused a severe outbreak in Europe in 2011. The strain TY-2482 sequenced from this outbreak allowed the discovery of its closest relatives but failed to resolve ways in which it originated and evolved. On account of the previous statement, may we expect similar upcoming outbreaks to occur recurrently or spontaneously in the future? The inability to answer these questions shows limitations of the current comparative and evolutionary genomics methods.status: publishe
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