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1.
Neth Heart J ; 28(5): 229-239, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31981094

RESUMO

The current paper presents a position statement of the Dutch Working Group of Transcatheter Heart Valve Interventions that describes which patients with aortic stenosis should be considered for transcatheter aortic valve implantation and how this treatment proposal/decision should be made. Given the complexity of the disease and the assessment of its severity, in particular in combination with the continuous emergence of new clinical insights and evidence from physiological and randomised clinical studies plus the introduction of novel innovative treatment modalities, the gatekeeper of the treatment proposal/decision and, thus, of qualification for cost reimbursement is the heart team, which consists of dedicated professionals working in specialised centres.

2.
Neth Heart J ; 25(3): 200-206, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27882524

RESUMO

AIMS: Acute aortic dissection (AD) requires immediate treatment, but is a diagnostic challenge. We studied how often AD was missed initially, which patients were more likely to be missed and how this influenced patient management and outcomes. METHODS: A retrospective cohort study including 200 consecutive patients with AD as the final diagnosis, admitted to a tertiary hospital between 1998 and 2008. The first differential diagnosis was identified and patients with and without AD included were compared. Characteristics associated with a lower level of suspicion were identified using multivariable logistic regression, and Cox regression was used for survival analyses. Missing data were imputed. RESULTS: Mean age was 63 years, 39% were female and 76% had Stanford type A dissection. In 69% of patients, AD was included in the first differential diagnosis; this was less likely in women (adjusted relative risk [aRR]: 0.66, 95% CI: 0.44-0.99), in the absence of back pain (aRR: 0.51, 95% CI: 0.30-0.84), and in patients with extracardiac atherosclerosis (aRR: 0.64, 95% CI: 0.43-0.96). Absence of AD in the differential diagnosis was associated with the use of more imaging tests (1.8 vs. 2.3, p = 0.01) and increased time from admission to surgery (1.8 vs. 10.1 h, p < 0.01), but not with a difference in the adjusted long-term all-cause mortality (hazard ratio: 0.76, 95% CI: 0.46-1.27). CONCLUSION: Acute aortic dissection was initially not suspected in almost one-third of patients, this was more likely in women, in the absence of back pain and in patients with extracardiac atherosclerosis. Although the number of imaging tests was higher and time to surgery longer, patient outcomes were similar in both groups.

3.
Br J Anaesth ; 105(2): 131-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20538739

RESUMO

BACKGROUND: Epiaortic ultrasound scanning (EUS) is regarded as the reference standard for detecting atherosclerosis in the ascending aorta (AA). Combined with appropriate surgical modifications, EUS use can significantly reduce the incidence of postoperative stroke when detecting severe AA atherosclerosis. A recently introduced modification of conventional transoesophageal echocardiography (TOE), known as the A-View method, has proven capable of inspecting the distal AA. The objective of this study was to quantify the diagnostic accuracy of modified TOE in assessing atherosclerosis of the distal AA. METHODS: After approval by the institutional medical ethical committee and after obtaining written informed consent, 465 consecutive patients above 65 yr old, undergoing elective cardiac surgery with a median sternotomy, were included. The study followed a cross-sectional diagnostic design. All consecutive patients underwent modified TOE followed by EUS (reference standard) to assess the severity of distal AA atherosclerosis. We constructed contingency tables to compare the presence (and severity) of atherosclerosis, detected by the two techniques. RESULTS: The positive predictive value of modified TOE for the detection of clinically significant atherosclerosis was 67%, and the negative predictive value was 97%. The sensitivity was 95% and the specificity was 79%. One patient suffered a pulmonary haemorrhage, although he recovered without further sequelae. We did not observe any clinical significant haemodynamic or ventilatory effects. CONCLUSIONS: The high negative predictive value and sensitivity show that modified TOE yields adequate diagnostic accuracy for excluding clinically relevant aorta atherosclerosis without significant cardiopulmonary side-effects, provided that the A-View catheter is introduced carefully.


Assuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Aterosclerose/diagnóstico por imagem , Procedimentos Cirúrgicos Cardíacos , Ecocardiografia Transesofagiana/métodos , Cuidados Pré-Operatórios/métodos , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/complicações , Aterosclerose/complicações , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ecocardiografia Transesofagiana/efeitos adversos , Métodos Epidemiológicos , Feminino , Humanos , Masculino , Esterno/cirurgia , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle
4.
J Dent Res ; 86(5): 421-5, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17452561

RESUMO

Non-contact plaque removal offers advantages in interproximal spaces, fissures, and pockets. It requires the generation of strong fluid flows and the inclusion of air bubbles to become effective. A pair of co-adhering streptococci and actinomyces has been used previously to demonstrate non-contact removal by sonic brushing. Here we determined the influence of the sequence of co-adhesion of streptococci and actinomyces on non-contact removal from a salivary pellicle by rotary and sonic brushing. After bacterial adhesion, pellicles were brushed in a wet and immersed state, with a distance up to 4 mm to the bristle tips. Bacteria adhering to pellicles from the sequence streptococci followed by actinomyces appeared more difficult to remove and left more large co-aggregates than from the sequence actinomyces followed by streptococci. At contact, rotary and sonic brushing performed equally well in bacterial removal, while at 4 mm, both had lost some efficacy.


Assuntos
Aderência Bacteriana , Película Dentária/microbiologia , Escovação Dentária/métodos , Actinomyces , Eletricidade , Feminino , Humanos , Pressão Hidrostática , Masculino , Streptococcus oralis , Escovação Dentária/instrumentação , Ultrassom
5.
Br J Anaesth ; 98(4): 434-41, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17337475

RESUMO

BACKGROUND: Atherosclerosis of the ascending aorta (AA) and stroke after cardiac surgery are related. Knowledge of the location of AA-atherosclerosis pre-sternotomy allows changes in surgical strategy to avoid manipulation of the AA. The gold-standard for assessment of AA-atherosclerosis is intraoperative epiaortic ultrasound scanning (EUS). Transoesophageal echocardiography (TOE) is unable to detect atherosclerosis in the distal AA due to the 'blind spot'. A new method [A-View (Aortic-view) method] using a fluid-filled catheter may enhance the assessment of distal AA-atherosclerosis. The aim of this study was to evaluate whether the A-View method indeed visualizes the distal AA and to assess the safety of this technology. METHODS: In a cross-sectional diagnostic study, 41 patients undergoing cardiac surgery including sternotomy underwent the same work-up including TOE, the A-View method, EUS, and routine operative monitoring. RESULTS: With the A-View method, the distal AA was visible in all (100%) patients. There were no clinical important side-effects associated with the use of the A-View catheter; however, in one patient the endotracheal tube was accidentally dislocated leading to a decrease in Sa(O2). Severity of atherosclerosis visualized with the A-View method compared with EUS results showed good agreement between the two methods [Kappa of 0.69 (0.50-0.88)]. The Bland-Altman analysis showed poor agreement in plaque-size measurements (bias 0.05 cm2, limits of agreement - 0.63 to 0.74 cm2). CONCLUSIONS: The A-View method offers a minimally invasive and safe approach to preoperatively resolving the blind spot of TOE. Compared with EUS, the A-View method yielded satisfactory results in the detection of AA-atherosclerosis. The A-View method seems a promising tool for patients undergoing cardiac surgery to direct surgical management.


Assuntos
Doenças da Aorta/diagnóstico por imagem , Aterosclerose/diagnóstico por imagem , Ecocardiografia Transesofagiana/instrumentação , Cuidados Intraoperatórios/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças da Aorta/complicações , Doenças da Aorta/patologia , Aterosclerose/complicações , Aterosclerose/patologia , Ponte de Artéria Coronária , Ecocardiografia Transesofagiana/efeitos adversos , Ecocardiografia Transesofagiana/métodos , Desenho de Equipamento , Feminino , Humanos , Cuidados Intraoperatórios/métodos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Sensibilidade e Especificidade , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle
6.
Ned Tijdschr Geneeskd ; 149(16): 845-9, 2005 Apr 16.
Artigo em Holandês | MEDLINE | ID: mdl-15868985

RESUMO

A 78-year-old man presented with dyspnoea and a 57-year-old with chest pain. Both had a history of coronary atherosclerosis and were now found to have a cardiac murmur. They proved to have a ventricular septal rupture (VSR) that had not been recognized as such. In the older man, the myocardial infarction that caused the VSR had initially not been recognized and in both men the clinical course was erroneously attributed to heart failure caused by myocardial infarction alone. Both underwent surgical correction of the VSR; the older man died due to postoperative intestinal necrosis, the younger man recovered. Patients with a high cardiac-risk profile, atypical chest pain, symptoms ofdyspnoea and a new specific murmur should be suspected of having a VSR. Early recognition and treatment of VSR may reduce mortality significantly.


Assuntos
Insuficiência Cardíaca/complicações , Ruptura Cardíaca Pós-Infarto/diagnóstico , Idoso , Dor no Peito/etiologia , Doença da Artéria Coronariana/complicações , Evolução Fatal , Sopros Cardíacos/etiologia , Ruptura Cardíaca Pós-Infarto/patologia , Ruptura Cardíaca Pós-Infarto/cirurgia , Septos Cardíacos/lesões , Septos Cardíacos/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Fatores de Risco
7.
Caries Res ; 38(2): 85-90, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14767163

RESUMO

This study compared removal of pairs of co-adhering and non-co-adhering oral actinomyces and streptococci from salivary pellicles by manual, rotating/oscillating electric and sonic toothbrushes, applying weights up to 240 g. First, actinomyces were allowed to adhere to a pellicle in a parallel plate flow chamber, after which streptococci suspended in saliva were perfused through the chamber at 33 degrees C. On average, 34-39% of the adhering bacteria were adhering as single organisms. For co-adhering and non-co-adhering pairs, 33 and 10% of the adhering bacteria were involved, respectively, in aggregates comprising more than 10 organisms. Brushing by hand removed 82% at low weight (40 g), which was less than by electric (93%) or sonic (92%) brushing, while for all modes of brushing bacterial removal increased with increasing weight to 95-99%. For a non-co-adhering pair, subsequent exposure of brushed pellicles to a streptococcal suspension yielded only 2-16% of bacteria involved in large aggregates, regardless of the mode of brushing. For the co-adhering pair, however, de novo streptococcal adhesion to hand-brushed pellicles yielded 34-57% of bacteria involved in large aggregates, while electric and sonic brushing left 22-35% of the bacteria involved in large aggregates. De novo streptococcal adhesion for the co-adhering pair increased with increasing weight for the electric and sonic brush in contrast to the manual brush. Since a strong influence of co-adhesion is evident in de novo streptococcal adhesion, despite nearly complete removal of all actinomyces, these observations suggest that the three modes of brushing leave footprints to which streptococci preferentially adhere.


Assuntos
Actinomyces/fisiologia , Aderência Bacteriana , Película Dentária/microbiologia , Saliva/microbiologia , Streptococcus/fisiologia , Escovação Dentária/métodos , Eletricidade , Desenho de Equipamento , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Microscopia de Contraste de Fase , Quartzo , Som , Streptococcus oralis/fisiologia , Streptococcus sanguis/fisiologia , Fatores de Tempo , Escovação Dentária/instrumentação
8.
Eur J Oral Sci ; 111(6): 459-64, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14632680

RESUMO

Coadhesion between oral microbial pairs is an established factor in the spatiotemporal development and prevalence of mixed-species communities in early dental plaque in vivo. This study compares removal and de novo adhesion of pairs of coadhering and non-coadhering oral actinomyces and streptococci by sonic brushing on salivary pellicles in a non-contact mode as a function of the distance between the brush and the pellicle surface in vitro. First, actinomycetes were adhered to a pellicle surface, after which streptococci suspended in saliva were allowed to adhere. Removal was examined by non-contact, sonic brushing with a wetted brush on a either a wetted or a substratum immersed to a depth of 7 mm. After brushing, de novo adhesion of streptococci to brushed pellicles was studied. For coadhering and non-coadhering pairs, 34% and 9%, respectively, of the adhering bacteria were involved in aggregates comprising more than 10 organisms. Non-contact, sonic brushing removed up to 99% of the adhering bacteria, regardless of the state of immersion of the substratum. Bacterial removal decreased with increasing distance of up to 6 mm between brush and pellicle surface. For the non-coadhering pair, subsequent exposure of pellicles to a streptococcal suspension yielded about 6% of bacteria involved in large aggregates. Alternatively, de novo adhesion of the coadhering streptococcal strain to pellicles brushed on the wetted substratum yielded 31% of bacteria involved in large aggregates, but after brushing the immersed substratum only 12% of the adhering bacteria were found in large aggregates. It is concluded that non-contact sonic brushing, under immersion, removes high percentage of adhering bacterial pairs up to a distance of 6 mm between the brush and the pellicle surface. However, non-contact, sonic brushing with only a thin wet film on the substratum may leave footprints to which streptococci preferentially adhere.


Assuntos
Aderência Bacteriana/fisiologia , Depósitos Dentários/microbiologia , Película Dentária/microbiologia , Placa Dentária/microbiologia , Saliva/microbiologia , Escovação Dentária/métodos , Actinomyces/fisiologia , Depósitos Dentários/prevenção & controle , Placa Dentária/prevenção & controle , Feminino , Humanos , Técnicas In Vitro , Masculino , Streptococcus oralis/fisiologia , Streptococcus sanguis/fisiologia , Escovação Dentária/instrumentação , Ultrassom , Molhabilidade
9.
Biomaterials ; 24(9): 1663-70, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12559826

RESUMO

The aim of this study is to determine rigid gas permeable (RGP) lens surface properties prior to and after wear that are influential on adhesion of Pseudomonas aeruginosa. After 10 and 50 days of wear and after end-stage use, lenses were collected for determination of physico-chemical surface properties and bacterial adhesion in a parallel plate flow chamber. Water contact angles on unused RGP lenses amounted 47+/-13 degrees and were affected by wear. In addition, %O at the lens surfaces, as determined by X-ray photoelectron spectroscopy increased after use for 10 and 50 days, but decreased after end-stage wear. The %N hardly increased after wear and, in line, SDS-PAGE did not indicate adsorbed proteins. The surface roughness of the lenses, as measured by atomic force microscopy amounted 9 nm after 10 and 50 days of use, but end-stage lenses were significantly rougher (48+/-23 nm). Moreover, initial deposition of P. aeruginosa #3 increased with increasing roughness for end-stage lenses. Multiple regression analysis, however, revealed that both physical and chemical surface properties were predictive for initial bacterial deposition to lens surfaces. After 10 days of wear, bacterial deposition was governed by the water contact angle, surface roughness, %O, %N, and %Si, while after 50 days of wear the surface roughness, %N, and %Si were found predictive for bacterial deposition. Initial bacterial deposition to end-stage lenses was solely dependent on the surface roughness. Summarizing, physico-chemical surface properties of RGP lenses change slightly during the first 10-50 days of wear, but end-stage lenses all had increased surface roughness, concurrent with increased bacterial adhesion.


Assuntos
Aderência Bacteriana/fisiologia , Lentes de Contato Hidrofílicas , Pseudomonas aeruginosa/fisiologia , Humanos , Pseudomonas aeruginosa/isolamento & purificação , Análise de Regressão
10.
Neth Heart J ; 10(1): 23-24, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25696029

RESUMO

A young male patient, just recovered from a recent transient ischaemic attack, was operated on for mitral valve insufficiency due to suspected endocarditis. Multiple wear-and-tear lesions were found at the line of closure of the mitral valve, which appeared to be Lambl's excrescences. The valve was replaced.

11.
Biomaterials ; 22(24): 3217-24, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11700793

RESUMO

The aim of this paper was to determine the adhesion of two physico-chemically characterized bacterial strains to a surface hydrophilic (CL A, water contact angle 57 degrees) and hydrophobic (CL B, water contact angle 106 degrees) hydrogel contact lens (CL) with and without an adsorbed tear film in a parallel plate flow chamber. Hydrophobicity (by water contact angles), charge (by particulate microelectrophoresis) and elemental composition (by XPS) of the surfaces of seven bacterial strains were characterized, after which two strains were selected for further studies. On CL surfaces, hydrophobicity, elemental composition, and mean surface roughness (by AFM) were determined, as well as the protein composition of tear films adsorbed on these lenses (by sodium dodecylsulphate-polyacrylamide gel electrophoresis (SDS-PAGE)). Bacterial cell surfaces were relatively uncharged and water contact angles on lawns of different strains ranged from hydrophobic to hydrophilic. After adsorption of tear film components, N/C elemental surface concentrations increased on CL A and CL B and differences in water contact angles between both lenses reduced to range from 57 degrees (CL A) to 69 degrees (CL B). However, different protein compositions were inferred. The surface roughness of CL A increased from 4 to 13 nm. while it remained 16 nm for CL B. Adhesion of hydrophobic Pseudomonas aeruginosa #3 was more extensive than of hydrophilic Staphylococcus aureus 799, with no differences between both lenses. The hydrophobicity of P. aeruginosa #3 after cell surface damage decreased and its adhesion was reduced on CL A and strongly on CL B. In addition, passage of an air-liquid interface yielded more detachment of S. aureus 799 than of P. aeruginosa #3 from the CL surfaces. In conclusion, the hydrophobicity of CL surfaces dictates the composition of the adsorbed tear film and therewith plays an important role in bacterial adhesion to lenses. Adhesion of hydrophobic P. aeruginosa #3 was more tenacious than of hydrophilic S. aureus 799.


Assuntos
Aderência Bacteriana , Materiais Biocompatíveis/efeitos adversos , Lentes de Contato Hidrofílicas/efeitos adversos , Lentes de Contato/efeitos adversos , Biofilmes/crescimento & desenvolvimento , Fenômenos Químicos , Físico-Química , Humanos , Técnicas In Vitro , Ceratite/etiologia , Teste de Materiais/instrumentação , Microscopia de Força Atômica , Pseudomonas aeruginosa/patogenicidade , Pseudomonas aeruginosa/fisiologia , Staphylococcus aureus/patogenicidade , Staphylococcus aureus/fisiologia , Eletricidade Estática , Propriedades de Superfície , Lágrimas/química
12.
J Heart Lung Transplant ; 20(9): 996-1004, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11557195

RESUMO

BACKGROUND AND OBJECTIVE: Recently, we have shown, by using localized in vivo phosphorus-31 magnetic resonance spectroscopy (31P MRS) of the anterior left ventricular wall, that brain death (BD) is not associated with reduced myocardial energy status. In this study, we applied ex vivo 31P MRS of the entire heart to study the effects of BD on the energy status of the feline donor heart following explantation. METHODS: We used cats (6 BD and 6 controls [C]) in a 26-hour protocol. After 2 hours of preparation, we induced BD by filling an intracranial balloon at t = 0 hour. At t = 6 hours, the hearts were arrested with St. Thomas' Hospital cardioplegic solution, explanted, and stored in the same solution at 4 degrees C in a 4.7 Tesla magnet for 17 hours. Subsequently, the hearts were reperfused in the Langendorff mode at 38 degrees C for 1 hour. The first 5-minute 31P MRS spectrum was obtained 1 hour after crossclamping the aorta; we obtained subsequent spectra every hour during storage and every 5 minutes during reperfusion. At the end, the hearts were dried and weighed. Phosphocreatine (PCr), gamma-adenosine triphosphate (gamma-ATP), inorganic phosphate (Pi), and phosphomonoesters (PME), were expressed per g dry heart weight. The intracellular pH (pH(i)) and the PCr/ATP ratio were calculated. RESULTS: During storage, we identified a significant but similar decrease of pH(i), PCr/ATP ratio, and PCr in both groups. During reperfusion, pH(i) and PCr/ATP ratio recovered similarly in both groups, whereas the recovery of PCr in the BD group was significantly lower (p < 0.05). The Pi and PME increased in both groups during storage but to a lesser extent in the BD group (p < 0.05). This difference disappeared during reperfusion. The gamma-ATP was already significantly lower in the BD group at the onset of storage, and this remained so throughout storage and reperfusion (p < 0.05 vs C). Contractile capacity was lost in all hearts, except for 1 heart in the BD group. CONCLUSION: Brain death-related failure of the energetic integrity of the feline donor heart becomes apparent only when using 31P MRS during ischemic preservation and subsequent reperfusion.


Assuntos
Morte Encefálica/diagnóstico por imagem , Morte Encefálica/metabolismo , Metabolismo Energético/fisiologia , Transplante de Coração/diagnóstico por imagem , Coração/diagnóstico por imagem , Coração/fisiopatologia , Reperfusão Miocárdica , Animais , Pressão Sanguínea/fisiologia , Líquidos Corporais/metabolismo , Temperatura Corporal/fisiologia , Gatos , Modelos Animais de Doenças , Frequência Cardíaca/fisiologia , Hemodinâmica/fisiologia , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Masculino , Modelos Cardiovasculares , Contração Miocárdica/fisiologia , Miocárdio/metabolismo , Fósforo/metabolismo , Cintilografia , Doadores de Tecidos
13.
J Microbiol Methods ; 45(2): 95-101, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11311394

RESUMO

Bacterial cell surfaces play a crucial role in their adhesion to surfaces. In the present study, physico-chemical cell surface properties of Pseudomonas aeruginosa, isolated from a case of contact lens associated keratitis, are determined for mid-exponential and early stationary phase cells and for cells after exposure to a lens care solution or after mechanical damage by sonication. Exposure to a lens care solution and mechanical cell surface damage reduced the cell surface hydrophobicity and water contact angles decreased from 129 degrees to 96 degrees and 83 degrees, respectively. Zeta potentials in saline (-9 mV) were hardly affected after mechanical damage, but tri-modal zeta potential distributions, with subpopulation zeta potentials at -11, -28 and -41 mV, were observed after exposure of bacteria to a lens care solution. X-ray photoelectron spectroscopy indicated changes in the amounts of oxygen-, nitrogen- and phosphorus-rich cell surface components. Mid-exponential phase cells had more nitrogen-rich cell surface components than early stationary phase cells, but water contact angles and zeta potentials were not very different. In addition, mid-exponential phase cells adhered better than early stationary phase cells to hydrophobic and hydrophilic substrata in a parallel plate flow chamber. The capacity of P. aeruginosa to adhere was decreased after inflicting cell surface damage. Exposure to a lens care solution yielded a larger reduction in adhesion capacity than sonication, likely because sonication left most of the cells in a viable state, in contrast to exposure to a lens care solution. It is argued that for clinically relevant experiments, it may be preferable to work with surface damaged cells rather than with gently harvested organisms.


Assuntos
Aderência Bacteriana/fisiologia , Soluções para Lentes de Contato/farmacologia , Lentes de Contato/microbiologia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Aderência Bacteriana/efeitos dos fármacos , Ciclo Celular , Parede Celular/química , Parede Celular/efeitos dos fármacos , Parede Celular/fisiologia , Contagem de Colônia Microbiana , Vidro , Polimetil Metacrilato , Infecções por Pseudomonas/prevenção & controle , Pseudomonas aeruginosa/química , Pseudomonas aeruginosa/efeitos dos fármacos , Elastômeros de Silicone , Sonicação , Propriedades de Superfície/efeitos dos fármacos
14.
Ann Transplant ; 6(4): 43-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-12035458

RESUMO

OBJECTIVE: To onset of brain death (BD) is associated with a hyperdynamic cardiovascular response caused by the acute sympathetic release of catecholamines. This is followed by progressive hemodynamic deterioration which may preclude heart donation for transplantation. The mechanism of the hemodynamic collapse is not fully understood. Changes in plasma concentrations of non-adrenergic non-cholinergic (NANC) substances, neuropeptide-Y (NP-Y, a vasoconstrictor) and the vasodilators calcitonin gene-related peptide (CGRP) and substance P (SP), were studied in relation to BD-related hemodynamic alterations. MATERIALS AND METHODS: Cats (6 BD and 6 controls (C)) were studied for 6 h. Heart rate (HR) and mean arterial pressure (MAP) were monitored. BD was induced at t = O min. At t = -5, 15, 60, 180 and 360 min, 5 ml arterial blood samples were taken. The plasma was collected and analyzed. The correlations between MAP and NANC levels were calculated. RESULTS: In the BD cats a maximal and significant increase in HR and MAP was observed at t = 2 min. HR returned to basal levels at t = 20 min and remained at that level. However, MAP deteriorated progressively to 53 +/- 8 mmHg (p 0.001 vs C) at/ = 360 min. NP-Y had increased from 59.7 +/- 2.5 to 110 +/- 20.2 pmol/l (p 0.05 vs C) at t = 15 min, had returned to basal value at t = 60 min and remained at that level. CGRP levels were lower and SP levels did not change vs C but both showed a trend towards higher levels at t = 360 min. The correlations between MAP and NP-Y, CGRP and SP appeared to be not significant. CONCLUSION: No evidence for participation of NANC substances could be demonstrated in brain death-related hemodynamic deterioration of the feline potential heart donor.


Assuntos
Morte Encefálica/fisiopatologia , Transplante de Coração , Hemodinâmica , Doadores de Tecidos , Animais , Pressão Sanguínea , Temperatura Corporal , Peptídeo Relacionado com Gene de Calcitonina/sangue , Gatos , Hidratação , Frequência Cardíaca , Masculino , Neuropeptídeo Y/sangue , Respiração , Substância P/sangue , Fatores de Tempo
15.
Neth Heart J ; 9(2): 85-86, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-25696700

RESUMO

An adult female was admitted for emergency surgery of a massively bleeding suspected aneurysm of the descending aorta. It proved to be a rupture of an aneurysm of a nonpatent ductus arteriosus or ductal diverticulum, a very rare lesion that is usually diagnosed on post-mortem. Adhesion of a previous ipsilateral lobectomy contributed to her survival. The aneurysm was resected.

18.
J Heart Lung Transplant ; 18(12): 1189-97, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10612377

RESUMO

OBJECTIVE: Long-term exposure of the donor heart to high dosages of dopamine in the treatment of brain death-related hemodynamic deterioration has been shown to reduce myocardial phosphocreatine (PCr) and adenosine triphosphate (ATP) in myocardial biopsy specimens and may preclude heart donation for transplantation. Short-term exposure to the acute catecholamine release during the onset of brain death has shown an unchanged PCr/ATP ratio using in vivo phosphorus-31 magnetic resonance spectroscopy (31P MRS). In this study 31P MRS was used to evaluate in vivo myocardial energy metabolism during long-term dopamine treatment. METHODS: Twelve cats were studied in a 4.7 Tesla magnet for 360 minutes. At t = 0 minutes, brain death was induced (n = 6). At 210 minutes, when myocardial workload in the brain-death group was reduced significantly, dopamine was infused (n = 12) at 5 microg/kg/min and its dose was consecutively doubled every 30 minutes and was withheld during the last 30 minutes of the experiment. Phosphorus-31 magnetic resonance spectra were obtained from the left ventricular wall during 5-minute time frames, and PCr/ATP ratios were calculated. The hearts were histologically examined. RESULTS: Although significant changes in myocardial workload were observed after the induction of brain death and during support and withdrawal of dopamine in both groups, the initial PCr/ATP ratio of 2.00+/-0.12 and the contents of PCr and ATP did not vary significantly. Histologically identified sub-endocardial hemorrhage was observed in 3 of 6 of the brain-dead animals and in 1 of 6 of the control animals. CONCLUSIONS: High dosages of dopamine in the treatment of brain death-related reduced myocardial workload do not alter PCr/ATP ratios and the contents of PCr and ATP of the potential donor heart despite histologic damage.


Assuntos
Morte Encefálica/metabolismo , Dopamina/farmacologia , Metabolismo Energético , Coração/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Miocárdio/metabolismo , Trifosfato de Adenosina/análise , Animais , Gatos , Dopamina/administração & dosagem , Transplante de Coração , Masculino , Miocárdio/química , Fosfocreatina/análise , Radioisótopos de Fósforo
19.
Eur Arch Otorhinolaryngol ; 255(8): 410-3, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9801860

RESUMO

Biofilm formation on indwelling silicone rubber voice prostheses in laryngectomized patients is still the main reason for dysfunction of the valve, leading to frequent replacements. Within patient support groups in The Netherlands, laryngectomees have suggested that the consumption of buttermilk prolongs the life-time of indwelling silicone rubber voice prostheses. The aim of the present study was to compare biofilm formation on Groningen button voice prostheses in a so-called artificial throat. Ten prostheses were placed in a simulated control group and ten other prostheses in a group with a simulated consumption of 700 ml buttermilk three times a day. Biofilms were allowed to grow on the prostheses by inoculating two artificial throats with the total cultivable microflora (bacteria and yeasts) isolated from an explanted Groningen button voice prosthesis. After 3 days, one artificial throat was perfused three times daily with phosphate buffer (control group) for 8 days, while the other artificial throat was perfused with buttermilk. Prostheses removed from the artificial throat in the control group were covered with a thick biofilm. Scanning electron microscopy showed microcolonies growing into the silicone rubber, similar to the ingrowth observed on explanted Groningen buttons. The simulated consumption of buttermilk in the other artificial throat almost fully prevented the formation of a biofilm on the prostheses during the experimental period. These in vitro experiments in the artificial throat demonstrate that the deterioration of voice prostheses can be lessened by the daily intake of buttermilk through its inhibitory effects on biofilm formation.


Assuntos
Biofilmes , Laringe Artificial , Leite , Elastômeros de Silicone , Animais , Candidíase/microbiologia , Candidíase/prevenção & controle , Bovinos , Laringectomia , Laringe Artificial/microbiologia
20.
J Heart Lung Transplant ; 17(10): 984-90, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9811406

RESUMO

BACKGROUND: Hemodynamic deterioration resulting from brain death-induced myocardial left ventricular dysfunction may preclude heart donation. A reduced myocardial high-energy phosphate content, assessed by biopsy specimens, has been suggested to be responsible for this phenomenon. By applying phosphorus 31 magnetic resonance spectroscopy, in vivo myocardial high-energy phosphate metabolism can be studied continuously. METHODS: Twelve cats were sedated, intubated, ventilated, and studied for 240 minutes. Heart rate, arterial blood pressure, and arterial blood gases were monitored. Central venous pressure was kept constant. Myocardial work was expressed as rate-pressure product (RPP=heart rate x systolic arterial blood pressure). After sternotomy a radio frequency surface coil was positioned onto the left ventricle. A parietal trephine hole was drilled, and an inflatable balloon was inserted. The animal was placed into a 4.7 T horizontal 40 cm bore magnet interfaced to a spectrometer. Brain death (n=6) was induced by rapid inflation of the balloon; the six other cats served as a sham-operated control group. 31P spectra were obtained in 30 seconds, with ventilation and arterial blood pressure curve triggering. The phosphocreatine/to/adenosine triphosphate ratio, as an estimator of energy metabolism, was calculated. RESULTS: Brain death was established within 30 seconds after inflation of the balloon. Changes in RPP were characterized by a triphasic profile with a maximum increase from 19.3+/-1.4 x 10(3) to 87.5+/-8.1 x 10(3) mm Hg x min(-1) (p < .0001 vs control group) at 2 minutes after inflation of the balloon. Subsequently, RPP decreased and was normalized at 15 minutes after inflation. The third phase was characterized by hemodynamic deterioration, which became significant at 180 minutes and resulted in mean arterial pressure of 71+/-12 mm Hg (p < .05 vs control group) at the end of the experimental period. RPP deteriorated to 14.6+/-2.0 x 10(3) mm Hg x min(-1) (p < .05 vs control group) at 240 minutes. Because the heart rate remained constant during the third phase, the decrease in RPP was caused by a decrease in systolic arterial blood pressure. The initial phosphocreatine/adenosine triphosphate ratio of 1.65+/-0.16 varied to 1.52+/-0.06 at 2 minutes, and to 1.73 +/-0.17 (all values NS vs control group and vs initial ratio) at 240 minutes. CONCLUSIONS: The energy status of the heart is not affected by brain death. Therefore brain death-induced hemodynamic deterioration is not caused by impaired myocardial high-energy phosphate metabolism.


Assuntos
Trifosfato de Adenosina/metabolismo , Morte Encefálica/fisiopatologia , Hemodinâmica/fisiologia , Espectroscopia de Ressonância Magnética , Fosfocreatina/metabolismo , Disfunção Ventricular Esquerda/fisiopatologia , Animais , Pressão Sanguínea/fisiologia , Morte Encefálica/patologia , Gatos , Metabolismo Energético/fisiologia , Frequência Cardíaca/fisiologia , Masculino , Contração Miocárdica/fisiologia , Disfunção Ventricular Esquerda/patologia , Função Ventricular Esquerda/fisiologia
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