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1.
Z Gerontol Geriatr ; 49(3): 209-15, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27048298

RESUMO

BACKGROUND: Improvement of communication skills in nursing home staff is key to provide better care for dementia patients and decrease occupational mental stress. OBJECTIVES: An innovative train-the-trainer program to improve and maintain professional caregivers' social competencies in nursing home dementia care is described. DESIGN AND METHODS: Over a period of 6 months, a group of 6 senior staff members were qualified as program trainers (multiplicators) for the TANDEM training program, which qualified them to design, deliver, and evaluate training sessions that foster specific social competencies in dementia care. In a subsequent intervention study with 116 geriatric caregivers in 14 nursing homes, training was provided either by multiplicators (intervention group) or directly by project coworkers (control group). RESULTS: Participants in both groups improved their dementia-specific communication skills. In a follow-up survey, the intervention group also reported lasting reductions in mental stressors at work (p < 0.05) and occupational mental stress (p < 0.01) compared with the control group. CONCLUSIONS: The qualification of staff members in German nursing homes to be multiplicators for the TANDEM train-the-trainer program for dementia-specific communication skills has a beneficial influence on social competencies, mental stressors at work, and occupational mental stress of staff who care for dementia patients and may contribute to a sustainable implementation of dementia-specific social competencies.


Assuntos
Demência/enfermagem , Demência/psicologia , Comunicação em Saúde , Casas de Saúde , Recursos Humanos de Enfermagem/educação , Capacitação de Professores/organização & administração , Adulto , Currículo , Alemanha , Instituição de Longa Permanência para Idosos , Humanos , Pessoa de Meia-Idade , Habilidades Sociais , Recursos Humanos
2.
Br J Anaesth ; 113(3): 474-83, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24694683

RESUMO

BACKGROUND: Whereas the effects of various inspiratory ventilatory modifications in lung injury have extensively been studied, those of expiratory ventilatory modifications are less well known. We hypothesized that the newly developed flow-controlled expiration (FLEX) mode provides a means of attenuating experimental lung injury. METHODS: Experimental acute respiratory distress syndrome was induced by i.v. injection of oleic acid in 15 anaesthetized and mechanically ventilated pigs. After established lung injury ([Formula: see text]ratio <27 kPa), animals were randomized to either a control group receiving volume-controlled ventilation (VCV) or a treatment group receiving VCV with additional FLEX (VCV+FLEX). At predefined times, lung mechanics and oxygenation were assessed. At the end of the experiment, the pigs were killed, and bronchoalveolar fluid and lung biopsies were taken. Expression of inflammatory cytokines was analysed in lung tissue and bronchoalveolar fluid. Lung injury score was determined on the basis of stained tissue samples. RESULTS: Compared with the control group (VCV; n=8), the VCV+FLEX group (n=7) demonstrated greater dynamic lung compliance and required less PEEP at comparable [Formula: see text] (both P<0.05), had lower regional lung wet-to-dry ratios and lung injury scores (both P<0.001), and showed less thickening of alveolar walls (an indicator of interstitial oedema) and de novo migration of macrophages into lung tissue (both P<0.001). CONCLUSIONS: The newly developed FLEX mode is able to attenuate experimental lung injury. FLEX could provide a novel means of lung-protective ventilation.


Assuntos
Expiração/fisiologia , Lesão Pulmonar/prevenção & controle , Lesão Pulmonar/fisiopatologia , Respiração Artificial/métodos , Síndrome do Desconforto Respiratório/fisiopatologia , Síndrome do Desconforto Respiratório/terapia , Animais , Biópsia , Líquido da Lavagem Broncoalveolar , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Pulmão/metabolismo , Pulmão/patologia , Complacência Pulmonar/fisiologia , Lesão Pulmonar/etiologia , Lesão Pulmonar/metabolismo , Masculino , Ácido Oleico , Respiração com Pressão Positiva/métodos , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Troca Gasosa Pulmonar/fisiologia , Respiração Artificial/efeitos adversos , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/patologia , Índice de Gravidade de Doença , Suínos
3.
Z Gerontol Geriatr ; 42(2): 108-16, 2009 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-18357423

RESUMO

The purpose of this study was to develop and evaluate a skill training aimed at increasing the social competence of caregivers of nursing home residents suffering from dementia. Herewith, the professional burden and occupational stress of the caregivers should be reduced and the quality of life of dementia patients should be increased. The contents of the training focused on problems and strategies in the communication with dementia patients and the communication with colleagues. The effectiveness of the intervention was tested in a controlled training study using a multiple control group design and process measurement. The participants of the trainings were 53 nursing home professionals, who were in daily contact with residents suffering from dementia. The results of the study verify effects for all relevant variables. The "social competence" of the caregivers increased and their "work stress" decreased while the "quality of life of dementia patients" increased. Therefore it can be concluded that training the social competence of nursing home professionals is a method to indirectly reduce their work stress and support dementia patients. The results of research in this program underline very clearly that the developed training is an effective option to improve the situation of dementia care in nursing homes. To make the intervention widely applicable we are currently developing a "multiplier program" in a follow-up project.


Assuntos
Competência Clínica/estatística & dados numéricos , Comunicação , Demência/enfermagem , Educação em Enfermagem/organização & administração , Relações Enfermeiro-Paciente , Casas de Saúde/estatística & dados numéricos , Ensino/métodos , Idoso , Idoso de 80 Anos ou mais , Educação em Enfermagem/métodos , Educação em Enfermagem/estatística & dados numéricos , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Avaliação em Enfermagem , Avaliação de Programas e Projetos de Saúde
4.
Sci Rep ; 9(1): 5889, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30971712

RESUMO

Environmental pollution with plastic waste has gained increasing attention, as the contamination of aquatic habitats poses a challenge to these ecosystems. Plastic waste has direct negative effects on animals such as reduced growth rate, fecundity or life span. However, the indirect effects of plastic waste, which has the ability to sorb chemicals from the surrounding media, on chemical communication have yet to be investigated. Chemical communication is crucial for aquatic organisms, e.g., to avoid predation. The planktonic water flea Daphnia (Crustacea), an important link between trophic levels, relies on info-chemicals (kairomones) to assess its current predation risk and to form inducible defences. We show that plastic waste, composed of high-density polyethylene (HDPE) and polyethylene terephthalate (PET) interferes with the formation of inducible defences in Daphnia longicephala when exposed to a combination of kairomones of Notonecta glauca and plastic waste. D. longicephala shows a reduction in all defensive traits, including body length, crest width and time until primiparity, compared to exposure to solely kairomone conditioned media. Plastic waste in the absence of kairomones had no effect on defensive traits. Since it is vital to adjust these defences to the current predation risk, any misperception can have far-reaching ecological consequences. Therefore, plastic waste can have indirect effects on organisms, which may manifest at the community level.


Assuntos
Daphnia/efeitos dos fármacos , Ecossistema , Plásticos/toxicidade , Animais , Tamanho Corporal/efeitos dos fármacos , Daphnia/fisiologia , Hemípteros/metabolismo , Feromônios/química , Feromônios/farmacologia , Plásticos/química , Polietileno/química , Polietileno/toxicidade , Comportamento Predatório/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade
5.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 2953-2956, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30441019

RESUMO

The number of implantable bidirectional neural interfaces available for neuroscientific research applications is still limited, despite the rapidly increasing number of customized components. We previously reported on how to translate available components into "ready-to-use" wireless implantable systems utilizing components off-the-shelf (COTS). The aim of the present study was to verify the viability of a micro-electrocorticographic ($\mu $ECoG) device built by this approach. Functionality for both neural recording and stimulation was evaluated in an ovine animal model using acoustic stimuli and cortical electrical stimulation, respectively. We show that auditory evoked responses were reliably recorded in both time and frequency domain and present data that demonstrates the cortical electrical stimulation functionality. The successful recording of neuronal activity suggests that the device can compete with existing implantable systems as a neurotechnological research tool.


Assuntos
Encéfalo , Eletrocorticografia , Animais , Potenciais Evocados Auditivos , Neurofisiologia , Próteses e Implantes , Ovinos
6.
Br J Pharmacol ; 151(6): 771-8, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17519947

RESUMO

BACKGROUND AND PURPOSE: Doxorubicin causes a chronic cardiomyopathy in which reactive oxygen species (ROS) accumulate over time and are associated with genetic and functional lesions of mitochondria. Dexrazoxane is a cardioprotective iron chelator that interferes with ROS production. We aim to analyze the effects of dexrazoxane on mitochondria in the prevention of doxorubicin-induced chronic myocardial lesions. EXPERIMENTAL APPROACH: Wistar rats (11 weeks of age) were injected with intravenous doxorubicin (0.8 mg kg(-1) weekly for 7 weeks) with or without simultaneous dexrazoxane (8 mg kg(-1)). Animals were killed at 48 weeks. Cardiomyopathy was scored clinically and histologically and cardiac mitochondria were analyzed. KEY RESULTS: Compared to control rats receiving saline, rats treated with doxorubicin alone developed a clinical, macroscopic, histological and ultrastructural cardiomyopathy with low cytochrome c-oxidase (COX) activity (26% of controls). The expression of the mtDNA-encoded COX II subunit was reduced (64% of controls). Myocardia exhibited a high production of ROS (malondialdehyde 338% and superoxide 787% of controls). Mitochondria were depleted of mitochondrial DNA (mtDNA copy number 46% of controls) and contained elevated levels of mtDNA deletions. Dexrazoxane co-administration prevented all these effects of doxorubicin on mitochondria, except that hearts co-exposed to doxorubicin and dexrazoxane had a slightly lower mtDNA content (81% of controls) and mtDNA deletions at low frequency. CONCLUSIONS AND IMPLICATIONS: Dexrazoxane prevented doxorubicin induced late-onset cardiomyopathy and also protected the cardiac mitochondria from acquired ultrastructural, genetic and functional damage.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Fármacos Cardiovasculares/uso terapêutico , Doxorrubicina/efeitos adversos , Mitocôndrias Cardíacas/efeitos dos fármacos , Razoxano/uso terapêutico , Animais , Cardiomiopatias/induzido quimicamente , Cardiomiopatias/fisiopatologia , Cardiomiopatias/prevenção & controle , Fármacos Cardiovasculares/farmacologia , DNA Mitocondrial/efeitos dos fármacos , Complexo IV da Cadeia de Transporte de Elétrons/efeitos dos fármacos , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Metabolismo Energético/efeitos dos fármacos , Expressão Gênica , Masculino , Malondialdeído/metabolismo , Mitocôndrias Cardíacas/genética , Fosforilação Oxidativa/efeitos dos fármacos , Ratos , Ratos Wistar , Razoxano/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Superóxidos/metabolismo
7.
Knee ; 12(1): 51-5, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15664878

RESUMO

Aim of the study was to create an animal model for the investigation of the role of subchondral bone damage without initial cartilage lesion in the pathogenesis of osteoarthritis, the mechanical properties of the joints as well as its role in cartilage metabolism. Therefore, after cadaver studies an animal model was created to apply a transarticular load to the femoro-patellar joint under reproducible conditions and produce a pure subchondral damage without affecting the articular cartilage. Following the cadaver studies a first group of four dogs was impacted to identify forces to produce isolated subchondral fractures in the femoral condyle. Then a second group of 12 dogs knee joints was impacted under identical conditions with forces of approximately 2100 N to produce similar subchondral fractures without cartilage damage in one joint under MRI control: T1-weighted SE-sequences. T2-weighted TSE, fat suppressed TIRM-sequences and 3D-FLASH fat saturated sequences. FLASH 3D-sequences revealed intact cartilage after impact in all cases and TIRM-sequences showed subchondral fractures representing bleeding, microfractures and fragmented bone trabecules. Turbo spin echo sequences and T1-weighted images revealed other intact intraarticular structures such as ligaments and menisci. The proposed experimental animal model is suitable to investigate the effect of pure subchondral damage on the articular cartilage and on means of treatment of cartilage defects without surgical intervention and without initial cartilage damage.


Assuntos
Traumatismos do Joelho/patologia , Osteoartrite do Joelho/patologia , Animais , Cartilagem Articular/patologia , Contusões/patologia , Cães , Fraturas do Fêmur/patologia , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Modelos Animais , Estresse Mecânico
8.
Immunol Lett ; 48(2): 117-21, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8719109

RESUMO

By selectively inbreeding diabetic individuals, we have been able to establish an NOD mouse population with a genetic predisposition towards insulin-dependent diabetes mellitus (IDDM) in approximately 100% of cases. We examined the preventive effect of 15-DS or 15DS + CyA on developing IDDM in these animals. Whereas 15-DS has been proved to be effective in preventing diabetes (significant decrease of the diabetic risk ratio to 0.368 and a reduction of the incidence of the disease to 46.7%), combined treatment with CyA did not produce any additional benefit.


Assuntos
Ciclosporina/farmacologia , Diabetes Mellitus Tipo 1/prevenção & controle , Guanidinas/farmacologia , Hipoglicemiantes/farmacologia , Animais , Ciclosporina/uso terapêutico , Diabetes Mellitus Tipo 1/imunologia , Quimioterapia Combinada , Feminino , Guanidinas/uso terapêutico , Hipoglicemiantes/uso terapêutico , Imunossupressores/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Distribuição Aleatória
9.
Shock ; 4(3): 216-24, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8574758

RESUMO

To investigate the effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on sepsis, chronically catheterized conscious pigs were challenged with Pseudomonas aeruginosa (8 x 10(7) colony-forming units kg-1 h-1) for 84 h (Group A, n = 8). Group B (n = 7) also received rhG-CSF at 5 micrograms kg-1 d-1, the first dose being given 30 min before starting bacterial infusion. Two of the animals in Group A died from pulmonary failure, whereas all those treated with rh-GCSF survived. Fever, severe pulmonary hypertension and systemic hypotension--the latter accompanied at first by a transient hypodynamic, and later a hyperdynamic response--were observed in all of the animals. In Group B, however, the rise in temperature, mean pulmonary arterial pressure (at a later stage of the observation), plasma levels of tumor necrosis factor, and endotoxin were significantly less than in Group A. In the rhG-CSF-treated pigs, an initial leukopenia completely recovered within 24 h (p < .05 vs. Group A). These data suggest that rhG-CSF might be beneficial in the treatment of sepsis.


Assuntos
Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Hemodinâmica/efeitos dos fármacos , Pulmão/fisiopatologia , Infecções por Pseudomonas/tratamento farmacológico , Sepse/tratamento farmacológico , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Feminino , Pulmão/efeitos dos fármacos , Masculino , Distribuição Aleatória , Proteínas Recombinantes/uso terapêutico , Testes de Função Respiratória , Sepse/sangue , Sepse/fisiopatologia , Suínos
10.
Shock ; 9(2): 128-34, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9488258

RESUMO

BACKGROUND: Neutrophils are of great importance for the host's defense against invading organisms. Granulocyte colony-stimulating factor (G-CSF) has been used to augment both the neutrophil number and function, and its prophylactic administration has proved beneficial in animal models of sepsis. However, pretreatment with G-CSF is not practical under clinical conditions. We therefore investigated the effect of recombinant human (rh)G-CSF, administered only after infection, on the survival rate as well as the hemodynamic and cytokine response of the animals. METHODS: Chronically catheterized conscious pigs were challenged with Pseudomonas aeruginosa (8 x 10(7) colony-forming units kg(-1) x h(-1) for 120 h (control group, n = 10). Animals in the G-CSF group (n = 7) also received rhG-CSF (5 microg kg(-1) x day(-1)), the first dose being given 3 h after beginning bacterial infusion. RESULTS: The mortality rate was 50% (5/10) and 29% (2/7) in the control and G-CSF groups, respectively (p = NS, control vs. G-CSF group). Fever, severe pulmonary hypertension, and a hyperdynamic response were recorded in all of the animals. In spite of a prompt and significant recovery from the initial leukopenia (p < .05 vs. control group), the animals of the G-CSF group showed no significant differences in the parameters investigated from those of the controls. Compared with the survivors, the interleukin-1 receptor antagonist was markedly elevated in all nonsurvivors after 6 h of sepsis (p < .05). CONCLUSIONS: These data suggest that treatment with rhG-CSF after the onset of bacterial sepsis might not significantly improve the chances of survival for non-neutropenic patients.


Assuntos
Bacteriemia/tratamento farmacológico , Bacteriemia/mortalidade , Citocinas/sangue , Fator Estimulador de Colônias de Granulócitos/farmacologia , Infecções por Pseudomonas/tratamento farmacológico , Animais , Sangue/microbiologia , Gasometria , Pressão Sanguínea/efeitos dos fármacos , Citocinas/efeitos dos fármacos , Modelos Animais de Doenças , Hemodinâmica/efeitos dos fármacos , Humanos , Proteína Antagonista do Receptor de Interleucina 1 , Ventilação Pulmonar/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Sialoglicoproteínas/sangue , Taxa de Sobrevida , Suínos , Fatores de Tempo , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/efeitos dos fármacos
11.
J Heart Lung Transplant ; 18(6): 597-606, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10395358

RESUMO

BACKGROUND: With the aim to expand the severely limited donor pool by use of non-heart-beating donors we developed a technique for successful transplantation of hearts after 30 minutes of normothermic ischemia without donor pretreatment. METHODS: In control groups hearts were transplanted in a conventional fashion using crystalloid cardioplegia (Group I, n = 6) or BCP (Group II, n = 8) for induction of cardiac arrest. In the ischemic groups hearts were harvested after 30 minutes of normothermic ischemia, perfused with blood cardioplegia (BCP) (Group III, n = 9) or BCP containing the Na(+)-H(+)-exchange inhibitor HOE 642 (Group IV, n = 8) and transplanted orthotopically. RESULTS: All animals could be weaned from cardiopulmonary bypass. Low dose inotropic support was necessary in the ischemic groups only. Recovery of the maximal left ventricular stroke work index (LVSWImax) in Groups I vs II was 62.6+/-19.6% vs 73.3+/-23.3% (NS), maximal right ventricular stroke work index (RVSWImax) averaged 61.1+/-18.8 vs 87.8+/-31.7% (NS) as compared to the preoperative level. In the ischemic groups (III vs IV) LVSWImax was 27.3+/-11.7 vs 59.5+/-32.4% (p = 0.038), RVSWImax was 27.4+/-20.9 vs 64.2+/-46.6% (NS). CONCLUSIONS: The results indicate that (a) successful pig heart transplantation after 30 minutes of normothermic ischemia is possible without donor pretreatment, and (b) that HOE 642 improves posttransplant LVSWImax significantly.


Assuntos
Parada Cardíaca/fisiopatologia , Transplante de Coração/fisiologia , Mudanças Depois da Morte , Animais , Sobrevivência de Enxerto/fisiologia , Parada Cardíaca/patologia , Testes de Função Cardíaca , Transplante de Coração/patologia , Miocárdio/patologia , Preservação de Órgãos , Suínos , Temperatura
12.
Intensive Care Med ; 22(8): 795-804, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8880249

RESUMO

OBJECTIVE: Study on simultaneous O2 supply/uptake relationships in liver and gut during endotoxaemia, to determine whether signs of dysoxia develop uniformly in the splanchnic region. DESIGN: Animal study to assess the early effects of endotoxaemia on oxygenation of both liver and small intestine. INTERVENTIONS: Eight anaesthetized pigs received a continuous portal venous infusion of lipopolysaccharide (0.5 microgram.kg-1.h-1) for 6 h. Systemic, pulmonary and splanchnic haemodynamics as well as systemic and splanchnic O2 supply/uptake relationships were determined. RESULTS: There was a multiphasic haemodynamic response pattern characterized by an early (within the 1st h) and a subsequent more prolonged phase (between the 2nd and 6th h) of decreases and recovery of hepatic arterial, portal venous and superior mesenteric arterial blood flows (electromagnetic flow probes) and splanchnic O2 deliveries. Unrelated to perfusion pressure and O2 delivery, there were early and sustained decreases in ileal mucosal surface partial pressure of oxygen (PO2) (multiwire PO2 electrode) and pH (tonometry). This was not reflected by ileal serosal surface PO2, O2 uptake and arteriomesenteric venous pH and partial pressure of carbon dioxide (PCO2) gradients. There was little evidence of concomitant hepatic dysoxia as evaluated by surface PO2. CONCLUSIONS: The study demonstrates early and sustained regional (mucosa) intestinal hypoxia with little evidence of simultaneous hepatic dysoxia during initial endotoxaemia.


Assuntos
Endotoxemia/fisiopatologia , Intestino Delgado/irrigação sanguínea , Fígado/irrigação sanguínea , Oxigênio/sangue , Animais , Endotoxemia/complicações , Hemodinâmica , Hipóxia/etiologia , Intestino Delgado/metabolismo , Lipopolissacarídeos , Fígado/metabolismo , Consumo de Oxigênio , Circulação Pulmonar/fisiologia , Fluxo Sanguíneo Regional , Circulação Esplâncnica/fisiologia , Estatísticas não Paramétricas , Suínos
13.
AJNR Am J Neuroradiol ; 15(3): 493-502, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8197946

RESUMO

PURPOSE: To assess the efficacy of metal stents for the treatment of different forms and sizes of carotid aneurysms. METHODS: A total of 14 experimentally constructed aneurysms in dogs were treated with transfemorally placed balloon-expandable tantalum and self-expanding nitinol stents. RESULTS: In 10 cases, stenting produced either immediate complete occlusion of the aneurysm (n = 7) or complete delayed thrombosis after 7 to 10 days (n = 3). In two cases treated with balloon-expandable tantalum endoprostheses, repeated angiography showed a persistent aneurysmal neck with a diameter of 1 mm. No incompletely occluded aneurysms were visible after implantation of nitinol stents. Nine-month angiographic follow-up revealed maximal stenosis of the stented vessel segment of up to 40% after placement of tantalum endoprostheses. However, no more than 15% stenosis followed the deployment of nitinol stents. Histologic examination confirmed these findings. Significantly greater intimal fibrocellular tissue growth surrounded tantalum filaments than nitinol filaments, which were covered with a smooth, thin neointimal layer. In two carotid arteries a subtotal and total occlusion of the parent vessel occurred after the insertion of a tantalum and nitinol stent, respectively. No recanalization of completely occluded aneurysms or delayed migration of a stent was observed. CONCLUSIONS: Porous, tubular self-expanding nitinol stents may become the treatment of choice for broad-based and fusiform aneurysms of the internal carotid artery. However, blood flow dynamics of the aneurysms must be studied carefully in order to select an appropriate mesh size for complete occlusion while preserving the parent vessel. Improvements in the introducing system, stent material, and stent shape are required for simple implantation and reduction of intimal hyperplasia.


Assuntos
Aneurisma/terapia , Doenças das Artérias Carótidas/terapia , Stents , Animais , Modelos Animais de Doenças , Cães
14.
Cardiol Clin ; 12(4): 673-87, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7850837

RESUMO

Knitted flexible tantalum stents proved to be a valuable adjunct to percutaneous transluminal angiplasty (PTA) in the case of insufficient PTA results, and their use was established in the distal aorta, the iliac, the femoro-popliteal, the renal, and the coronary arteries. Recently, long arterial occlusions were defined as new indications for primary stenting; stent indications were further extended to the subclavian, the carotid, and the splanchnic arteries. Due to higher incidence of acute and late complications after stent treatment of small diameter arteries, patients have to be selected thoroughly. Newly designed drug-releasing stents tested in animal experiments promised to be suitable to diminish the incidence of late restenosis due to intinal hyperplasia, thus providing better long-term patency.


Assuntos
Arteriopatias Oclusivas/terapia , Stents , Angioplastia com Balão , Angioplastia Coronária com Balão , Aorta Abdominal , Doenças da Aorta/terapia , Estenose das Carótidas/terapia , Doença das Coronárias/terapia , Desenho de Equipamento , Feminino , Artéria Femoral , Humanos , Artéria Ilíaca , Masculino , Pessoa de Meia-Idade , Artéria Poplítea , Obstrução da Artéria Renal/terapia , Tantálio
15.
Eur J Cardiothorac Surg ; 14(6): 607-14, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9879873

RESUMO

OBJECTIVES: The aim of our study was to develop a surgical technique for a successful transplantation of hearts harvested after 30 min of normothermic ischemia without donor pretreatment. Successful transplantation of ischemic compromised hearts could help to expand the severely limited donor pool. We used the pig model because this species is very susceptible to myocardial ischemia. Na+-H+-exchange (NHE) inhibitors have shown excellent protective properties in several in vitro and in vivo models of myocardial ischemia and reperfusion. METHODS: In group I (n=12) hearts were harvested after 30 min of normothermic ischemia following cardiac arrest induced by exsanguination. Hearts were perfused with warm blood cardioplegia and transplanted orthotopically. In group II (n=9) controlled reperfusion with cold leucocyte-depleted blood cardioplegia was performed after 30 min of normothermic ischemia. In group III (n=8) the same procedure was performed as in group II but blood cardioplegia contained 1 mmol/l HOE 642. RESULTS: In group I massive myocardial oedema was observed and none of the animals could be weaned from cardiopulmonary bypass (CPB). In contrast, all animals in groups II and III could be weaned from CPB with low dose inotropic support. In groups II and III the contractility of the hearts, expressed as maximal left and right ventricular stroke work index was significantly impaired after transplantation as compared with the preoperative value. Supplementation of blood cardioplegia with HOE 642 resulted in a significantly better recovery of the LVSWImax (Group II vs. III). CONCLUSIONS: Successful transplantation of pig hearts is possible after 30 min of normothermic ischemia without donor pretreatment if a controlled reperfusion with cold leucocyte-depleted blood cardioplegia is performed. HOE 642 given during reperfusion only improves posttransplant left ventricular function.


Assuntos
Soluções Cardioplégicas/química , Guanidinas , Parada Cardíaca Induzida/métodos , Transplante de Coração , Reperfusão Miocárdica/métodos , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores , Sulfonas , Animais , Sangue , Creatina Quinase/metabolismo , Isoenzimas , L-Lactato Desidrogenase/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Volume Sistólico/fisiologia , Suínos , Fatores de Tempo
16.
Eur J Cardiothorac Surg ; 19(3): 321-5, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11251273

RESUMO

OBJECTIVE: Nitroxides have strong antioxidant capacity but their effectiveness is limited by their rapid intracellular inactivation. Polynitroxyl-Albumin (PNA) is capable of regenerating inactivated nitroxide. We tested the effect of PNA against reperfusion injury in heart transplantation. METHODS: Pig hearts were transplanted orthotopically. In the control group (n=9) reperfusion was performed without reperfusion modifications. In the experimental group (n=10) 1 ml/kg PNA was given before cross-clamp release. RESULTS: Hemodynamic performance was impaired after transplantation in both groups without significant intergroup differences. Plasma malonedialdehyde levels were significantly diminished in the PNA group as compared to the controls. CK-MB levels in both groups were increased within the first 2 h of reperfusion without significant intergroup differences. In contrast, there were found significant higher values of myocardial specific lactate dehydrogenase (LD1) in the controls versus PNA group. CONCLUSIONS: PNA was able to reduce lipid peroxidation and attenuate free radical activity. Contractile dysfunction could no be improved, indicating that (a) the radical scavenging effect was to weak or (b) other mechanisms than free oxygen radicals are responsible for myocardial damage in this experimental model.


Assuntos
Albuminas/farmacologia , Sequestradores de Radicais Livres/farmacologia , Transplante de Coração/métodos , Isquemia Miocárdica/prevenção & controle , Óxidos de Nitrogênio/farmacologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Modelos Animais de Doenças , Transplante de Coração/mortalidade , Isquemia Miocárdica/enzimologia , Probabilidade , Valores de Referência , Sensibilidade e Especificidade , Estatísticas não Paramétricas , Taxa de Sobrevida , Suínos
17.
J Invest Surg ; 10(4): 183-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9284002

RESUMO

The purpose of this study was to develop a model of renal artery occlusion and to investigate the effects of various thrombolytic agents on an acute occlusion of the renal artery with respect to ischemic tolerance of renal parenchyma. In order to do this, a thrombosis model in dogs (n = 36) was established and a total of 72 dorsal renal arteries occluded using autologous clot material. For the in vitro preparing of a clot, autologous blood (20 mL) was withdrawn and 100 U thrombin immediately added. Then 1 mL of the clot material was injected into the dorsal branch of the exposed renal artery. The dogs were divided into 8 groups (2 control groups, 6 therapy groups with local and systemic thrombolytic therapy). Thrombolysis was performed using urokinase, single-chain urokinase, and recombinant tissue-plasminogen activator. In all cases the clot preparation technique allowed complete and stable occlusion of the renal arteries. Local and systemic application of the thrombolytic agents, however, resulted in complete recanalization of the clot material in all study groups. Recombinant tissue-plasminogen activator turned out to be the most effective agent in terms of recanalization time. The technique described allowed effective and reproducible artery occlusion for in vivo experimental work to study comparatively thrombolytic agents with respect to fibrin specificity, lytic efficacy, and side effects.


Assuntos
Fibrinolíticos/uso terapêutico , Obstrução da Artéria Renal/tratamento farmacológico , Animais , Modelos Animais de Doenças , Cães , Feminino , Masculino
18.
Plast Reconstr Surg ; 103(1): 138-44, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9915174

RESUMO

This study investigated the feasibility of prefabrication of a bilaminar-epithelialized flap by using a tissue expander and cultured keratinocytes, for reconstruction of perforate defects in the oral cavity and upper aerodigestive tract. In each of six rats, a 10-ml volume expander was implanted under the inferior epigastric flap and a thin silicon catheter was introduced into periexpander space. Seven days after implantation, 10 x 10(6) cultured keratinocytes, isolated from inbred donor rats, were suspended in fibrin glue and injected into the periexpander space through the catheter (n = 4 of 6). The expansion was started immediately after cell inoculation and lasted at least 3 weeks at the speed of 2 to 3 ml every 5 to 7 days. At the end of expansion, the periexpander space was opened and the capsule around the tissue expander was found to be covered completely with a neoepithelium. Thus, a bilaminar-epithelialized flap based on femoral vessels was elevated and successfully transferred to cover the excisional perforate defect in the oral cavity with the neoepithelial side as inner lining. All flaps treated with 10 x 10(6) cultured keratinocytes survived with complete wound healing during a 1-week follow-up (n = 4 of 6). Both macroscopic and histologic findings demonstrated that a bilaminar-epithelialized composite flap can be fabricated by using a tissue expander and keratinocyte-fibrin glue suspension.


Assuntos
Queratinócitos , Retalhos Cirúrgicos , Expansão de Tecido , Animais , Células Cultivadas , Células Epiteliais , Adesivo Tecidual de Fibrina , Masculino , Ratos , Ratos Wistar , Cicatrização
19.
J Cardiovasc Surg (Torino) ; 39(4): 445-53, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9788790

RESUMO

BACKGROUND: The present article deals with the conduct of our animal experiments with the human growth factor FGF (fibroblast growth factor) and the results obtained therefrom. METHODS: In order to establish the angiogenetic potential of FGF, this factor was first obtained from a genetically transformed strain of E. Coli, and then isolated and highly purified. Afterwards the growth factor FGF has been used in several in vitro- and in vivo experiments in order to prove its influence on neo-angiogenesis in ischemic tissue. RESULTS: In cultures of endothelial cells from the human great saphenous vein it has been possible to stimulate growth successfully with FGF obtained in this way, and a further increase in its action was brought about by the addition of heparin. In tritium-thymidine assays, the endothelial cell stimulating action of FGF was confirmed. It could also be shown angiographically that administering FGF to the ischemic myocardium of these animals initiates the development of new vessels, and we could demonstrate that a myocardial capillary network sprouting directly from the coronary vessels themselves can establish an alternative blood flow. These results were confirmed histologically by the significantly greater capillary density which appeared following the use of the growth factor. CONCLUSIONS: By using the human growth factor FGF, we have been able for the first time to understand the physiological processes of angiogenesis as they come into play during wound healing or the development of collaterals following tissue ischemia, and to use this knowledge for the production of new vessels in the ischemic hearts of rats and rabbits. Decisive for the future use of the factor in human patients -- particularly for the treatment of coronary heart disease (CHD) are the results of experimental investigations designed to exclude the possibility of the growth factor initiating or stimulating neoplasia.


Assuntos
Vasos Coronários/fisiopatologia , Fatores de Crescimento de Fibroblastos/farmacologia , Isquemia Miocárdica/fisiopatologia , Neovascularização Fisiológica/fisiologia , Animais , Divisão Celular , Células Cultivadas , Córion/efeitos dos fármacos , Córion/crescimento & desenvolvimento , Vasos Coronários/patologia , Endotélio Vascular/crescimento & desenvolvimento , Fatores de Crescimento de Fibroblastos/toxicidade , Humanos , Isquemia Miocárdica/patologia , Coelhos , Ratos , Ratos Endogâmicos Lew , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/patologia
20.
Lab Anim ; 31(3): 279-82, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9230510

RESUMO

The effects of a rapid increase in inspired desflurane concentration on systemic haemodynamics and plasma catecholamines were studied in seven pigs (22-30 kg). Following premedication (flunitrazepam 0.4 mg/kg i.m.), anaesthesia was induced (propofol 2.5 mg/kg i.v., vecuronium 0.2 mg/kg i.v.), the trachea orally intubated, and ventilation controlled. Anaesthesia was maintained with N2O/O2 (70%/30%), propofol (50 micrograms/kg/min), desflurane (2% end-tidal concentration), and vecuronium (0.3 mg/kg/h). After cannulation of both femoral arteries for subsequent simultaneous systemic pressure measurements and blood sampling for determination of epinephrine (E) and norepinephrine (NE) plasma levels, N2O and propofol were discontinued, and FiO2 and end-tidal concentration of desflurane increased to > 0.9 and 3%, respectively. Forty minutes later, the inspired concentration of desflurane was abruptly increased to 15%. Mean arterial pressure (MAP), heart rate (HR), and plasma concentrations of E and NE were determined before and 1, 2, 4, 8, 16, and 32 min after increasing the desflurane concentration. Plasma concentrations of E and NE were determined by high performance liquid chromatography (HPLC) with electrochemical detection. Data were analysed by repeated measures ANOVA (significance level P < 0.05). The abrupt increase in inspired desflurane concentration caused an insignificant increase (11%) in HR at 1, 2 and 4 min. There was an immediate decrease in MAP. Plasma levels of E and NE remained unchanged throughout. In conclusion, in contrast to findings in humans, a rapid increase in inspired desflurane concentration does not cause a hyperdynamic circulatory response in the pig.


Assuntos
Anestesia/veterinária , Anestésicos Inalatórios/efeitos adversos , Catecolaminas/sangue , Hemodinâmica/fisiologia , Isoflurano/análogos & derivados , Suínos/fisiologia , Anestésicos Inalatórios/administração & dosagem , Anestésicos Inalatórios/metabolismo , Anestésicos Intravenosos , Animais , Pressão Sanguínea/fisiologia , Catecolaminas/metabolismo , Desflurano , Epinefrina/sangue , Epinefrina/metabolismo , Feminino , Flunitrazepam/administração & dosagem , Flunitrazepam/efeitos adversos , Flunitrazepam/metabolismo , Moduladores GABAérgicos/administração & dosagem , Moduladores GABAérgicos/efeitos adversos , Moduladores GABAérgicos/metabolismo , Frequência Cardíaca/fisiologia , Hemodinâmica/efeitos dos fármacos , Isoflurano/administração & dosagem , Isoflurano/efeitos adversos , Isoflurano/metabolismo , Masculino , Fármacos Neuromusculares não Despolarizantes , Medicação Pré-Anestésica/efeitos adversos , Medicação Pré-Anestésica/veterinária , Propofol , Fatores de Tempo , Brometo de Vecurônio
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