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1.
Biomaterials ; 24(6): 989-1000, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12504521

RESUMEN

The aim of this study was to investigate the physicochemical and biological properties of a newly developed calcium phosphate cement (CaP cement) implanted in cortical bone. CaP cement was injected as a paste into tibia cortical bone defects in goats. Polymethylmethacrylate (PMMA) bone cement was used as a control. The animals were killed after 3 days, 2, 8, 16 and 24 weeks. X-ray diffraction and Fourier transform infrared spectroscopy performed at retrieved samples showed that the CaP cement had set as a carbonate apatite and remained stable over time. Light microscopic evaluation showed that after 2 weeks the cement was in tight contact with the bone without any inflammatory reaction or fibrous encapsulation. At later time points, the CaP cement implants were totally covered by a thin layer of bone and osteoclasts, present at the interface, which were clearly resorbing the cement. At locations where CaP cement was resorbed, new bone was deposited. Transmission electron microscopy revealed that indeed a seamless contact existed between CaP cement and bone, as characterized by the occurrence of an electron dense line of 50-60 nm thick that covered the CaP cement. Osteoblasts, in contact with the cement, were depositing new bone. Although the bulk of the material was still in situ after 24 weeks, the progressive osteoclast resorption of the cement followed by new bone formation suggests that all of the material may be replaced eventually. In contrast to the CaP cement, the PMMA reference cement was always surrounded by a thin fibrous capsule. The results indicate that the investigated CaP cement is biocompatible, osteoconductive as well as osteotransductive and is a candidate material for use as a bone substitute.


Asunto(s)
Cementos para Huesos/farmacología , Huesos/efectos de los fármacos , Tibia/citología , Animales , Huesos/citología , Huesos/ultraestructura , Fosfatos de Calcio/farmacología , Femenino , Cabras , Microscopía Electrónica , Polimetil Metacrilato/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Tibia/efectos de los fármacos , Factores de Tiempo , Difracción de Rayos X
2.
Intensive Care Med ; 27(7): 1200-9, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11534569

RESUMEN

OBJECTIVE: To investigate whether the adenosine-antagonist theophylline reduces the incidence of contrast-induced nephropathy (CIN). DESIGN AND SETTING: Prospective, comparison to series of patients at similar risk of CIN in a university hospital medical ICU. PATIENTS: 78 ICU patients with at least one risk factor for CIN undergoing 150 consecutive contrast examinations. INTERVENTIONS: Administration of 200 mg theophylline/70 kg BW intravenously 30 min before that of 100 ml or more low-osmolarity contrast medium (CM). MEASUREMENTS AND RESULTS: Concentrations of serum creatinine and blood urea nitrogen (BUN), urine volume, fluid balance, and the incidence of CIN [increase in creatinine > or =20.5 mg/dl (= 44.2 micromol/l) within 48 h] were monitored for 48 h. Despite the large number of risk factors (6.8 per patient) including a high dose of CM (169.4 ml), impaired renal function (51%), diabetes (38%), aminoglycosides (61%), vancomycin (53%), catecholamines (52%), creatinine concentrations were not increased 24 h (1.40+/-0.92 mg/dl) or 48 h (1.38+/-0.88 mg/dl) after CM [1.47+/-1.0 mg/dl (= 130+/-88 micromol/l)] vs. baseline. The fluid balance was not different before (+3 ml/h) and after CM (-9 ml/h). The urine volume slightly increased after CM and theophylline (184 ml/h vs. 164 ml/h). Only three patients (2%) developed CIN. The incidence was significantly lower than that of 14% (78/565) in the control series with patients at comparable risk of CIN (p < 0.0001). CONCLUSIONS: Using a theophylline prophylaxis the incidence of CIN in patients with increased risk of CIN is as low as 2%.


Asunto(s)
Adenosina/antagonistas & inhibidores , Medios de Contraste/efectos adversos , Enfermedades Renales/inducido químicamente , Inhibidores de Fosfodiesterasa/uso terapéutico , Teofilina/uso terapéutico , Anciano , Femenino , Alemania/epidemiología , Humanos , Incidencia , Unidades de Cuidados Intensivos , Enfermedades Renales/prevención & control , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Factores de Tiempo
3.
Endoscopy ; 32(10): 783-7, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11068838

RESUMEN

BACKGROUND AND STUDY AIMS: The contrast medium for endoscopic retrograde cholangiopancreatography (ERCP) must produce adequate images, whilst keeping the risk of complications to a minimum. There is a theoretical reason to suppose that a dimeric isosmolar medium may be superior to a monomeric hyperosmolar medium. We have compared two such media in a triple-centre double-blind randomized study on patients referred with a clinical indication for ERCP. PATIENTS AND METHODS: A total of 160 patients were randomly allocated to either lodixanol or lopromide. Assessments were made of the quality of images and the complications encountered. RESULTS: A total of 151 patients were evaluated. Apart from a trend towards better diagnostic quality for main pancreatic duct imaging with lodixanol, there were no differences between the two groups. The overall frequencies of adverse events were similar CONCLUSIONS: lodixanol is a safe and effective water-soluble contrast medium for ERCP, comparable to lopromide, but despite theoretical advantages lodixanol has no clear practical benefit.


Asunto(s)
Colangiopancreatografia Retrógrada Endoscópica/normas , Medios de Contraste , Yohexol/análogos & derivados , Ácidos Triyodobenzoicos , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad
4.
Circulation ; 101(12): 1396-402, 2000 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-10736283

RESUMEN

BACKGROUND: Hypertrophic cardiomyopathy is a myocardial disorder resulting from inherited sarcomeric dysfunction. We report a mutation in the myosin-binding protein-C (MyBP-C) gene, its clinical consequences in a large family, and myocardial tissue findings that may provide insight into the mechanism of disease. METHODS AND RESULTS: History and clinical status (examination, ECG, and echocardiography) were assessed in 49 members of a multigeneration family. Linkage analysis implicated the MyBP-C gene on chromosome 11. Myocardial mRNA, genomic MyBP-C DNA, and the myocardial proteins of patients and healthy relatives were analyzed. A single guanine nucleotide insertion in exon 25 of the MyBP-C gene resulted in the loss of 40 bases in abnormally processed mRNA. A 30-kDa truncation at the C-terminus of the protein was predicted, but a polypeptide of the expected size ( approximately 95 kDa) was not detected by immunoblot testing. The disease phenotype in this family was characterized in detail: only 10 of 27 gene carriers fulfilled diagnostic criteria. Five carriers showed borderline hypertrophic cardiomyopathy, and 12 carriers were asymptomatic, with normal ECG and echocardiograms. The age of onset in symptomatic patients was late (29 to 68 years). In 2 patients, outflow obstruction required surgery. Two family members experienced premature sudden cardiac death, but survival at 50 years was 95%. CONCLUSIONS: Penetrance of this mutation was incomplete and age-dependent. The large number of asymptomatic carriers and the good prognosis support the interpretation of benign disease.


Asunto(s)
Cardiomiopatía Hipertrófica/genética , Proteínas Portadoras/genética , Penetrancia , Adulto , Edad de Inicio , Anciano , Cardiomiopatía Hipertrófica/diagnóstico , Cromosomas Humanos Par 11 , Ecocardiografía , Electrocardiografía , Exones , Femenino , Ligamiento Genético , Genotipo , Heterocigoto , Humanos , Immunoblotting , Masculino , Persona de Mediana Edad , Mutación , Fenotipo
6.
Hum Genet ; 102(3): 299-304, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9544842

RESUMEN

Hypertrophic cardiomyopathy (HCM) is a genetically and clinically heterogeneous myocardial disease that is in most cases familial and transmitted in a dominant fashion. The most frequently affected gene codes for the cardiac (ventricular) beta-myosin heavy chain. We have investigated the genetic cause of an isolated case of HCM, which was marked by an extremely severe phenotype and a very early age of onset. HCM is normally not a disease of small children. The proband was a boy who had suffered cardiac arrest at the age of 6.5 years (resuscitation by cardioconversion). Upon screening of the beta-myosin heavy chain gene as a candidate, two missense mutations, one in exon 19 (Arg719Trp) and a second in exon 12 (Met349Thr), were identified. The Arg719Trp mutation was de novo, as it was not found in the parents. In contrast, the Met349Thr mutation was inherited through the maternal grandmother. Six family members were carriers of this mutation but only the proband was clinically affected. Segregation and molecular analysis allowed us to assign the Met349Thr mutation to the maternal and the Arg719Trp de novo mutation to the paternal beta-myosin allele. Thus, the patient has no normal myosin. We interpret these findings in terms of compound heterozygosity of a dominant (Arg719Trp) and a recessive (Met349Thr) mutation. Whereas a single mutated Arg719Trp allele would be sufficient to cause HCM, the concurrent Met349Thr mutation alone does not apparently induce the disease. Nevertheless, it conceivably contributes to the particularly severe phenotype.


Asunto(s)
Cardiomiopatía Hipertrófica/genética , Heterocigoto , Cadenas Pesadas de Miosina/genética , Mutación Puntual/genética , Edad de Inicio , Niño , Análisis Mutacional de ADN , Femenino , Humanos , Masculino , Linaje , Fenotipo , Polimorfismo Conformacional Retorcido-Simple
7.
Immunol Lett ; 41(1): 67-71, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7959905

RESUMEN

Chemotactic activity of granulocytes attracted by tumor cells loaded either with anti-ganglioside monoclonal antibodies (mAb) or with antibody-glucose oxidase conjugates (mAb-GO) was investigated. The melanoma cell line SK-Mel-28 which expresses the ganglioside GD3 at high density as well as the neuroectodermal cell line SK-N-LO which expresses GD2 were used for the experiments. In the presence of 50% human AB-serum, antibody-loaded tumor cells induced chemotactic activity on granulocytes, probably due to the generation of C3a/C5a which could be detected in serum incubated with anti-GD3 loaded SK-Mel-28 cells. Both compounds could also be detected in vivo in the plasma of patients suffering from neuroblastoma during therapy with anti-GD2 antibodies. In another set of experiments mAb-GO conjugates generating high amounts of H2O2 in the presence of glucose were bound to these tumor cells. A significant lipid peroxidation could be observed in the simultaneous presence of iron and ascorbate. The lipid peroxidation products were measured as thiobarbituric acid-reactive substances (TBARS) and were also shown to induce chemotactic effects on granulocytes.


Asunto(s)
Factores Quimiotácticos/biosíntesis , Granulocitos/inmunología , Sistema del Grupo Sanguíneo ABO , Anticuerpos Monoclonales , Quimiotaxis , Complemento C3a/análisis , Complemento C5a/análisis , Gangliósidos/inmunología , Glucosa Oxidasa/inmunología , Humanos , Peróxido de Hidrógeno/metabolismo , Peroxidación de Lípido , Melanoma/inmunología , Melanoma/patología , Tumores Neuroectodérmicos/inmunología , Tumores Neuroectodérmicos/patología , Células Tumorales Cultivadas
8.
Psychiatr Neurol Med Psychol (Leipz) ; 41(6): 321-33, 1989 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-2672060

RESUMEN

Transcranial Doppler sonography measures blood circulation rate in the basal sections of the cerebral arteries. The theoretic basis of the method is outlined, localisation and standard values are presented for the individual vessels are set out. Vascular constriction, angiospasms, and arteriovenous malformations may affect the blood circulation rate, and can be detected by use of this method. Further indications exist before, during, and after surgery, and in the case of excessive intracranial pressure. Functional angiograms of the basal cerebral vessels can be produced by means of three dimensional transcranial Doppler sonography.


Asunto(s)
Isquemia Encefálica/diagnóstico , Circulación Cerebrovascular , Ecoencefalografía/instrumentación , Velocidad del Flujo Sanguíneo , Humanos
9.
Zentralbl Gynakol ; 107(5): 294-9, 1985.
Artículo en Alemán | MEDLINE | ID: mdl-3993269

RESUMEN

In the period from 1970 to 1983 sterility treatment was broken off by 218 patients of the women's clinic, Wilhelm-Pieck-University Rostock. From 103 returned questionnaires 194 individual responses were recorded suggesting that on the average more than one reason led to the decision to break off treatment. Personal problems such as unsuccessful treatment, advanced age, too high demand on time, conflicts in marriage, consumption of stimulants, and diseases (61.2%) were prevalent. Pregnancy (50.5%), adoption (20.4%), occupational problems (13.6%), and a problematic physician-patient-relationship (6.8%) were also cited. Already from the beginning of treatment these patients were not willing to cooperate, to supply necessary information and fully participate. A tendency towards a shifting of the problems could be observed. 24.3% of the patients continued seeing a gynaecologist. 15.5% asked for recommencement of sterility treatment.


Asunto(s)
Infertilidad Femenina/psicología , Cooperación del Paciente , Adulto , Factores de Edad , Femenino , Humanos , Infertilidad Femenina/terapia , Relaciones Interpersonales , Masculino , Ocupaciones , Relaciones Médico-Paciente , Encuestas y Cuestionarios , Factores de Tiempo
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