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1.
Acta Biomater ; 6(3): 1006-13, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19800426

RESUMO

A novel titanium-based material, containing no toxic or expensive alloying elements, was compared to the established biomaterials: commercially pure titanium (c.p.Ti) and Ti6Al4V. This material (Ti/1.3HMDS) featured similar hardness, yield strength and better wear resistance than Ti6Al4V, as well as better electrochemical properties at physiological pH7.4 than c.p.Ti grade 1 of our study. These excellent properties were obtained by utilizing an alternative mechanism to produce a microstructure of very fine titanium silicides and carbides (<100 nm) embedded in an ultra-fine-grained Ti matrix (365 nm). The grain refinement was achieved by high-energy ball milling of Ti powder with 1.3 wt.% of hexamethyldisilane (HMDS). The powder was consolidated by spark plasma sintering at moderate temperatures of 700 degrees C. The microstructure was investigated by optical and scanning electron microscopy (SEM) and correlated to the mechanical properties. Fluorescence microscopy revealed good adhesion of human mesenchymal stem cells on Ti/1.3HMDS comparable to that on c.p.Ti or Ti6Al4V. Biochemical analysis of lactate dehydrogenase and specific alkaline phosphatase activities of osteogenically induced hMSC exhibited equal proliferation and differentiation rates in all three cases. Thus the new material Ti/1.3HMDS represents a promising alternative to the comparatively weak c.p.Ti and toxic elements containing Ti6Al4V.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Titânio/química , Titânio/farmacologia , Adulto , Células Cultivadas , Humanos , Teste de Materiais , Tamanho da Partícula , Propriedades de Superfície
2.
Transfus Med ; 8(3): 185-94, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9800290

RESUMO

There are no detailed data on blood use with regard to diagnoses of recipients during infancy, childhood and adolescence. Available information on this issue is incomplete and no longer current. We conducted a survey of blood component use in children and adolescents in an acute-care university hospital in the greater area of Nuremberg between June 1994 and September 1996. Packed red blood cells (RBCs), fresh-frozen plasmas (FFPs) and platelet (PLT) components were evaluated for the recipients discharge diagnoses. Source study files were extracted from the hospital transfusion service and the medical records department. Transfused units were listed by broad diagnostic categories and leading diagnostic groups formed from principal diagnoses of the recipients according to the International Classification of Diseases, 9th edn (ICD-9). 34.3% of 2869 RBC cell units, 35.0% of 1095 FFP units and 5.0% of 1028 PLT components were used in patients with congenital diseases, mainly cardiac defects. The disease category neoplastic diseases was next most frequently associated with blood transfusion diagnosed in recipients of 23.9% of all RBCs, 15.6% of all FFP units and in 66.4% of all PLT units. Malignant diseases and benign haematological diseases (diagnostic categories II and IV) accounted for 68.9% of all costs of blood component transfusion. These findings demonstrate the increased importance of platelet transfusion for the organization of local and regional blood donation programmes and for cost analysis exercises. The study shows that detailed information on local blood use may be obtained quickly using available data collections of transfusion services and medical record departments.


Assuntos
Bancos de Sangue/estatística & dados numéricos , Transfusão de Componentes Sanguíneos/estatística & dados numéricos , Hospitais Universitários/estatística & dados numéricos , Adolescente , Transfusão de Componentes Sanguíneos/economia , Criança , Pré-Escolar , Transfusão de Eritrócitos/estatística & dados numéricos , Feminino , Alemanha , Custos Hospitalares/estatística & dados numéricos , Sistemas de Informação Hospitalar , Hospitais Universitários/economia , Humanos , Lactente , Recém-Nascido , Masculino , Plasma , Transfusão de Plaquetas/estatística & dados numéricos
3.
Transfusion ; 37(10): 1075-83, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9354829

RESUMO

BACKGROUND: There are no recent studies on transfusion practice and blood use with regard to diagnoses of European recipients. We conducted a survey of blood component use, including packed red cells, fresh-frozen plasma, and platelets, in an acute-care university hospital in the Greater Nürnberg area. STUDY DESIGN AND METHODS: A survey was carried out of blood component transfusion at a university hospital (Erlangen, Germany) between June 1994 and May 1996. Transfused units were listed by broad diagnostic categories formed from principal diagnoses of the recipients according to the International Classification of Diseases, Ninth Revision. RESULTS: Among 100,497 discharged patients, 6,590 patients who received transfusion (6.6%) are represented in this survey. Of 28,440 red cell units and 8,592 fresh-frozen plasma units, 72.4 percent and 66.9 percent, respectively, were used in patients with neoplastic diseases, circulatory system diseases, or disorders of the digestive system. Of 2704 platelet units, 78.1 percent were transfused to patients with neoplastic or gastrointestinal diseases or diseases of blood-forming organs. These four diagnostic categories accounted for 77.7 percent of all costs of transfusion therapy. Males received 60.1 percent of all blood components transfused, and patients less than 65 years old received 68.0 percent. CONCLUSION: This survey provides information on blood component usage in a German university hospital. It demonstrates the concentration of today's blood utilization among a few diagnostic categories. The study shows that detailed information on local blood use may be obtained quickly by using data available from transfusion services and medical record departments. This information is relevant for quality management of transfusion practice, cost analyses and for planning local and regional blood donation programs.


Assuntos
Transfusão de Componentes Sanguíneos/estatística & dados numéricos , Idoso , Doenças Cardiovasculares/terapia , Doenças do Sistema Digestório/terapia , Feminino , Alemanha , Pesquisas sobre Atenção à Saúde , Neoplasias Hematológicas/terapia , Hospitais Universitários , Humanos , Masculino , Estudos Retrospectivos
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