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1.
Int J Surg Case Rep ; 72: 212-214, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32544831

RESUMO

BACKGROUND CONTEXT: Calciphylaxis is a rare complication of secondary hyperparathyroidism caused by calcifications of small blood vessels in the skin and soft tissue. The disease occurs almost exclusively in patients with chronic kidney disease and has an incidence of approximately 50 cases per year in Germany [1]. PURPOSE: We present a case of a 61-year-old woman with calciphylaxis in connection with a primary knee endoprosthesis implantation. STUDY DESIGN: Case report. METHODS: A review of the medical records since the time of initial hospital admission throughout the entire hospitalization until the death of the patient was performed. RESULTS: Calciphylaxis caused severe soft tissue complications after total joint arthroplasty. Despite interdisciplinary therapy, including revision and plastic surgery as well as intensive care, the patient died 4 months after primary total knee arthroplasty due to septic multi-organ failure. CONCLUSION: Calciphylaxis may cause severe soft tissue complications after total joint arthroplasty and should be considered as potential differential diagnosis to surgical site infection. This is the first case report on calciphylaxis as direct complication of total joint replacement surgery.

2.
Bone Joint Res ; 8(2): 41-48, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30915209

RESUMO

OBJECTIVES: Intra-articular injections of local anaesthetics (LA), glucocorticoids (GC), or hyaluronic acid (HA) are used to treat osteoarthritis (OA). Contrast agents (CA) are needed to prove successful intra-articular injection or aspiration, or to visualize articular structures dynamically during fluoroscopy. Tranexamic acid (TA) is used to control haemostasis and prevent excessive intra-articular bleeding. Despite their common usage, little is known about the cytotoxicity of common drugs injected into joints. Thus, the aim of our study was to investigate the effects of LA, GC, HA, CA, and TA on the viability of primary human chondrocytes and tenocytes in vitro. METHODS: Human chondrocytes and tenocytes were cultured in a medium with three different drug dilutions (1:2; 1:10; 1:100). The following drugs were used to investigate cytotoxicity: lidocaine hydrochloride 1%; bupivacaine 0.5%; triamcinolone acetonide; dexamethasone 21-palmitate; TA; iodine contrast media; HA; and distilled water. Normal saline served as a control. After an incubation period of 24 hours, cell numbers and morphology were assessed. RESULTS: Using LA or GC, especially triamcinolone acetonide, a dilution of 1:100 resulted in only a moderate reduction of viability, while a dilution of 1:10 showed significantly fewer cell counts. TA and CA reduced viability significantly at a dilution of 1:2. Higher dilutions did not affect viability. Notably, HA showed no effects of cytotoxicity in all drug dilutions. CONCLUSION: The toxicity of common intra-articular injectable drugs, assessed by cell viability, is mainly dependent on the dilution of the drug being tested. LA are particularly toxic, whereas HA did not affect cell viability.Cite this article: P. Busse, C. Vater, M. Stiehler, J. Nowotny, P. Kasten, H. Bretschneider, S. B. Goodman, M. Gelinsky, S. Zwingenberger. Cytotoxicity of drugs injected into joints in orthopaedics. Bone Joint Res 2019;8:41-48. DOI: 10.1302/2046-3758.82.BJR-2018-0099.R1.

3.
Osteoarthritis Cartilage ; 24(9): 1622-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27084349

RESUMO

OBJECTIVE: Acetabular chondral lesions are common in patients with femoroacetabular impingement (FAI) syndrome. The aim of this study was (1) to evaluate the proliferation potential of primary human chondrocytes (hC) derived from both acetabular and femoral site and (2) to validate cellular differentiation during three-dimensional (3D) cultivation as a prerequisite for autologous matrix-assisted cartilage regeneration of the hip joint. METHODS: hC were isolated from cartilage samples obtained from N = 6 patients during offset reconstruction. Proteoglycan content was assessed by Safranin-O staining. Proliferation and cell viability were quantified by microscopic cell counting and Trypan Blue exclusion. Messenger ribonucleic acid (mRNA) expression levels of collagen type 1 and 2, aggrecan (ACAN), and interleukin-1ß (IL-1ß) genes were assessed upon monolayer cultivation, after 48 h/4-10°C - transport simulation and after 14 days of 3D hydrogel cultivation. RESULTS: Primary hC from acetabular and femoral damaged sites were viable. No significant intergroup differences were observed concerning cell viability (>95%) after monolayer cultivation and transport simulation. Harvest yields from acetabular and femoral cartilage samples were comparable to that known from knee joints (mean ± standard deviation (SD), 13.4 × 10(6) ± 5 × 10(6) cells per culture vs 20 × 10(6) cells). Redifferentiation was induced during 3D hydrogel cultivation as observed by increased levels of collagen II (1000-fold) and ACAN (10-fold) gene vs monolayer cultivation (P < 0.001). CONCLUSION: hC derived from damaged acetabular and femoral site are qualified for autologous matrix-assisted cartilage transplantation paving the way for cell-based cartilage regeneration in FAI patients.


Assuntos
Impacto Femoroacetabular , Cartilagem Articular , Condrócitos , Quadril , Humanos , Interleucina-1beta
4.
Anaesthesiol Reanim ; 20(3): 60-70, 1995.
Artigo em Alemão | MEDLINE | ID: mdl-8526961

RESUMO

The main focus of this paper is to show regulative interactions between cardiac index (CI) and renal blood flow (RBF) with various intravenous anaesthetics under steady state conditions. Several experimental series were carried out on dogs with the following anaesthetic doses (as given per hour and per kilogram body weight-h-1 x kg-1): fentanyl 50 micrograms, ketamine 4 and 10 mg, and thiopentone 10 and 20 mg. The basic anaesthesia used was halothane (0.7 vol.%) in N2O/O2 (ratio about 3:1), because renal function, renal autoregulation and responsiveness to renally effective drugs remain nearly unaltered by this anaesthetic procedure. The experimental set-up allowed separate evaluation of effects caused by basic anaesthesia, by intravenous anaesthetic under examination or by the combination of both. All physiological parameters, such as blood gas parameters, plasma electrolytes and intravasal volume were kept in normal range throughout the experiments. Under all anaesthetics studied, RBF reflects the situation of general metabolism especially of cardiac output, as long as sympathetic innervation of the kidneys remains unaltered. Especially the relationship between RBF and CI corresponds with regulative effects in situations without anaesthesia. Within the blood pressure range of autoregulation RBF is greater under ketamine than normal and smaller under fentanyl and etomidate, whereas all other anaesthetics applied show no effect on RBF. Functional "denervation" of the kidney by means of epidural anaesthesia is capable of terminating those effects caused centrally by opioids and transmitted by sympathetic nerves. Diuresis is increased by thiopentone and by ketamine, whereas fentanyl reduces it. The activity of the plasma renin level does not correspond with the degree of renal vascular resistance. The effect of each anaesthetic drug on RBF has principally to be taken as regulative adaptation to altered circulatory conditions. Increasing plasma renin levels are mainly a compensatory reaction following a decline in arterial blood pressure due to anaesthesia induced sympathicolysis. With regard to renal function, the additional use of epidural anaesthesia (functional "denervation" of the kidney) can be recommended especially for highly invasive surgical procedures to antagonize reduction of RBF, which is often induced sympathetically by pain or by commonly used anaesthetic drugs.


Assuntos
Anestesia Epidural , Anestesia Geral , Anestésicos/farmacologia , Droperidol/farmacologia , Fentanila/farmacologia , Hemodinâmica/efeitos dos fármacos , Ketamina/farmacologia , Rim/irrigação sanguínea , Tiopental/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Taxa de Filtração Glomerular/efeitos dos fármacos , Homeostase/efeitos dos fármacos , Renina/sangue , Sistema Nervoso Simpático/efeitos dos fármacos
6.
Transpl Int ; 7(3): 177-81, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8060466

RESUMO

Over a 30-month period, 60 patients (30 in each group) suffering from end-stage liver disease or primary hepatic malignancy and scheduled for liver transplantation were enrolled in a prospective, randomized study to compare two methods of liver preservation: histidine-tryptophan-ketoglutarate (HTK) solution versus University of Wisconsin (UW) solution. Entry criteria for both groups were: age (18-65 years), elective surgery (transplantable or urgent category of the recipients), first transplantations and harvesting procedure performed by the same team. The parameters under investigation were the clinical and laboratory data pre- and post-transplantation, as well as follow-up data such as complications and survival. There were no significant differences in the two groups as far as the evaluation criteria were concerned, even when cold ischemia time was more than 15 h (n = 7). A slight, yet not significant, increase in late complications of the biliary anastomoses could be seen in the UW group. Hepatocellular injury (SGOT, SGPT, GLDH, lactate) appeared to be more marked in the HTK group. These results suggest that both HTK and UW solutions are appropriate for clinical use in liver transplantation, even if cold ischemia time is more than 15 h.


Assuntos
Soluções Cardioplégicas , Transplante de Fígado/fisiologia , Fígado/fisiologia , Soluções para Preservação de Órgãos , Preservação de Órgãos , Adenosina , Adolescente , Adulto , Idoso , Alopurinol , Feminino , Glucose , Glutationa , Sobrevivência de Enxerto/fisiologia , Humanos , Insulina , Testes de Função Hepática , Masculino , Manitol , Pessoa de Meia-Idade , Cloreto de Potássio , Procaína , Estudos Prospectivos , Rafinose
7.
Pathol Res Pract ; 190(5): 482-92, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-7991468

RESUMO

This study was undertaken in order to obtain information on the mode of reaction of the contractile apparatus after different forms of cardiac arrest, global ischemia and reperfusion, as well as on possible correlations between the contraction state of myofibrils and biochemical parameters. During the survival time, before the level of 3 mumol/gww creatine phosphate (CP) is reached, the contraction state shows only minor changes. During the revival time in which ATP tissue concentrations decay to 4 mumol/gww, the contribution of ATP, lactate, anorganic phosphate (Pa) and acidosis to the degree of relaxation depends on the method of cardiac arrest. At defined biochemical values, the degree of relaxation is comparable after aortic cross clamping (ACC) and St. Thomas perfusion, but significantly different compared to HTK perfusion. Thus, during the revival time, the relaxation of sarcomeres depends predominantly on the composition of the solutions used for cardiac arrest. The re-entry of contraction below 3 mumol/gww ATP is correlated with the ATP concentration, independent of the form of cardiac arrest. Reperfusion after HTK or St. Thomas cardioplegia and reversible ischemia leads to the focal formation of contraction bands, which do not occur during ischemia. This contraction state is significantly more pronounced after reperfusion of St. Thomas arrested hearts. Thus, the contraction state of myofibrils is influenced not only by alterations in metabolite concentrations, but also by the composition of cardioplegic solutions and by the characteristic conditions (sufficient energy, oxygen and Calcium) during reperfusion.


Assuntos
Parada Cardíaca/metabolismo , Parada Cardíaca/fisiopatologia , Contração Muscular/fisiologia , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Reperfusão Miocárdica , Miofibrilas/fisiologia , Trifosfato de Adenosina/análise , Trifosfato de Adenosina/metabolismo , Animais , Cálcio/análise , Cálcio/metabolismo , Cães , Metabolismo Energético , Parada Cardíaca/enzimologia , Lactatos/análise , Lactatos/metabolismo , Músculos/química , Músculos/metabolismo , Músculos/fisiologia , Isquemia Miocárdica/enzimologia , Miofibrilas/química , Miofibrilas/metabolismo , Oxigênio/análise , Oxigênio/metabolismo , Fosfocreatina/análise , Fosfocreatina/metabolismo
8.
Pathol Res Pract ; 189(3): 342-51, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8332576

RESUMO

This study investigates how far mitochondrial swelling in the ischemic heart is influenced by factors pertaining to anaerobic energy turnover. Canine hearts were arrested by aortic cross clamping or cardioplegically with St. Thomas or HTK solution and incubated at 25 degrees C in the solution used for cardiac arrest. Samples of the left ventricle were taken at the end of cardiac arrest and during ischemia for structural evaluation and biochemical analysis. The extracellular pH in the interventricular septum was measured. Mitochondrial swelling was determined with the surface to volume ratio, a parameter independent of the reference space. Values obtained for different swelling were related to defined metabolite concentrations and pHe values to establish possible correlations between structural and biochemical parameters in the ischemic heart. At the onset of ischemia and during the breakdown of creatine phosphate (CP) to 3 mumol/g wet weight mitochondrial volume depends on the method of cardiac arrest and does not increase significantly in any of the three groups. The degree of mitochondrial swelling after depletion of CP correlates with the decline in ATP independent of the form of cardiac arrest. Characteristic values of the surface to volume ratio ascertained at different times of ischemia for all groups correspond to determined ATP concentrations. Acid pHe values seem to intensify mitochondrial swelling. With increased lactate concentrations mitochondria swell, but first initially the degree of swelling differs significantly in the forms of cardiac arrest investigated. Thus, the surface to volume ratio is a powerful and valid ultrastructural parameter, which makes correlations between mitochondrial structure and metabolism possible and furthermore indicates a strong correlation between mitochondrial swelling and ATP-concentration in the ischemic heart.


Assuntos
Trifosfato de Adenosina/metabolismo , Dilatação Mitocondrial , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/patologia , Miocárdio/metabolismo , Miocárdio/patologia , Animais , Cães , Concentração de Íons de Hidrogênio , Lactatos/metabolismo , Ácido Láctico , Microscopia Eletrônica , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/ultraestrutura , Fosfocreatina/metabolismo
9.
Anat Rec ; 235(3): 425-35, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8430912

RESUMO

This study compares the ultrastructure of beating canine hearts with that of hearts subjected to different clinically common forms of cardiac arrest. The contraction state per test field was ascertained according to a specially developed classification. The volume density of myofibrils and the surface to volume ratio of mitochondria were used as parameters for cellular and mitochondrial swelling. Contraction bands were not found in any of the differently pretreated hearts. Following immersion fixation, contractions as well as over- and hypercontractions in beating, fibrillating, and St. Thomas-arrested hearts are significantly more pronounced than in HTK-arrested hearts. Cellular and mitochondrial volumes were similar in beating and fibrillating hearts. St. Thomas-perfusion significantly decreased cellular and mitochondrial volume compared to beating hearts, but these values were in the same range as in fibrillating hearts. Only HTK-solution actually led to a strong reduction of these compartments. Compared to immersion, perfusion fixation after coronary perfusion with cardioplegic solutions led to comparable cellular volumes, but significantly elevated the percentage of relaxed sarcomeres and significantly reduced mitochondrial swelling. The best structural preservation of myocytes was found after HTK-perfusion and perfusion fixation. Such ultrastructural quantitative and morphometrical parameters are powerful tools since results confirm that the degree of myocardial preservation depends on the method of cardiac arrest. This forms the basis for the choice of preconditions for subsequent ischemia. Furthermore, significant alterations of myocardial ultrastructure depend on a combination of the functional state of the heart, the method of cardioplegia, and the technique of fixation.


Assuntos
Parada Cardíaca Induzida , Contração Miocárdica , Miocárdio/citologia , Preservação Biológica , Fibrilação Ventricular/patologia , Animais , Bicarbonatos/farmacologia , Cloreto de Cálcio/farmacologia , Soluções Cardioplégicas/farmacologia , Cães , Glucose/farmacologia , Imersão , Magnésio/farmacologia , Manitol/farmacologia , Miocárdio/patologia , Miocárdio/ultraestrutura , Cloreto de Potássio/farmacologia , Procaína/farmacologia , Cloreto de Sódio/farmacologia , Fixação de Tecidos
10.
Langenbecks Arch Chir ; 378(4): 233-8, 1993.
Artigo em Alemão | MEDLINE | ID: mdl-8366735

RESUMO

In 22 human donor livers the measurement of the non-invasive bioelectrical impedance was performed prospectively to evaluate the degree of tissue damage sustained during cold ischemia. The results of the measurement were correlated with liver function, the method of organ preservation and the period of ischemia. The impedance was measured in vivo as 620 ohm (at 192 Hz), the phase angle as -7.4 degrees (at 5 kHz). The results were compared with the data obtained from 72 patients who underwent elective laparotomies. The 22 donor livers were studied further during ischemia. The method was found to be a reliable way of detecting severe damage to the hepatocytes during the cold ischemia.


Assuntos
Sobrevivência de Enxerto/fisiologia , Transplante de Fígado/fisiologia , Potenciais da Membrana/fisiologia , Preservação de Órgãos , Sobrevivência de Tecidos/fisiologia , Adolescente , Adulto , Membrana Celular/fisiologia , Sobrevivência Celular/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismo por Reperfusão/fisiopatologia
11.
Langenbecks Arch Chir ; 377(2): 81-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1583986

RESUMO

In order to study perfusion effects of different liver preservation methods on liver structure, porcine livers were perfused with either Bretschneider's HTK (Histidine Tryptophane Ketoglutarat) solution, Euro-Collins (EC) solution or University of Wisconsin solution (UW) according to the respective recommended protocols. Subsequently, together with a group of unprotected livers, all organs were examined by light and electron microscopy including computer assisted morphometry. The width of the space of Disse, the continuity of endothelial cells and the ultrastructure of the hepatocytes were not impaired after cold perfusion with any of the 3 solutions. However, we found considerable differences between the groups with respect to removal of blood cells from liver sinusoids. Livers flushed according to the HTK-protocol had the lowest residual blood cell content followed by the livers of the EC- and the UW-group. Centrilobular regions of the liver lobules were generally better washed free of blood than periportal zones. Computer assisted morphometry did not reveal any significant difference between the size of hepatocytes of EC-, UW- and HTK livers. Only the hepatocytes of normothermic control livers (biopsy samples) were 10% larger than hepatocytes of cold flushed groups. None of the protective perfusion protocols showed structural signs of perfusion injury.


Assuntos
Soluções Hipertônicas/farmacologia , Fígado/efeitos dos fármacos , Soluções para Preservação de Órgãos , Preservação de Órgãos/métodos , Soluções/farmacologia , Adenosina , Alopurinol , Animais , Feminino , Glucose/farmacologia , Glutationa , Insulina , Fígado/patologia , Manitol/farmacologia , Microscopia Eletrônica , Perfusão , Cloreto de Potássio/farmacologia , Procaína/farmacologia , Rafinose , Suínos
12.
Thorac Cardiovasc Surg ; 39(4): 174-82, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1948965

RESUMO

Cellular and mitochondrial swelling are regarded as typical intra-ischemic alterations ("IIA"), contraction band lesions (CBL), in contrast, as products of post-ischemic reperfusion. The occurrence of both types of structural deterioration was investigated in Purkinje fibres and subendocardial and intramural working myocardium: initially after St. Thomas- or HTK cardioplegia, then during ensuing global ischemia up to the "practical limit of resuscitability", and following post-ischemic reperfusion. Generally, Purkinje fibres are not better preserved than neighbouring working myocardium. Comparing St. Thomas- and HTK cardioplegia, considerable quantitative, but not qualitative differences in the reaction patterns of different cell types or layers arise. Immediately after cardioplegia, CBL are completely lacking in both cell types. During ischemia, CBL occur occasionally in Purkinje fibres and seldom in subendocardial working myocardium, "IIA" predominate. During post-ischemic reperfusion "IIA" tend to reverse in all layers, whereas CBL are found to remain in the subendocardial cell types. In intramural layers, CBL occur only during reperfusion. Thus, we deduce that cardioplegia only modulates the severity of "IIA" and the frequency of CBL, but cannot abolish the particular sensitivity of subendocardial Purkinje fibres to global ischemia. Prerequisites for the development of irreversible CBL are on the one hand ischemic metabolic alterations and corresponding energy deficits, and, on the other hand, a supply of oxygen. The oxygen may be inadequately supplied via diffusion during ischemia or may be subsequently provided by reperfusion.


Assuntos
Traumatismo por Reperfusão Miocárdica/patologia , Miocárdio/ultraestrutura , Ramos Subendocárdicos/ultraestrutura , Animais , Bicarbonatos , Cloreto de Cálcio , Soluções Cardioplégicas , Cães , Endocárdio/ultraestrutura , Glucose , Parada Cardíaca Induzida , Magnésio , Manitol , Cloreto de Potássio , Procaína , Cloreto de Sódio
13.
Phys Med Biol ; 36(6): 799-804, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1714610

RESUMO

A method was developed to quantify the intensity of tissue staining using a CCD (charge-coupled device) camera. Reflection spectra of NBT-stained (nitro-blue tetrazolium-stained) and unstained myocardium were recorded via fibre optics coupled to a CCD camera, connected to a microcomputer. The calculation of the intensity of staining was based on evaluation of the NBT-related changes of the reflectance spectrum. In each of six anaesthetized sheep, global ischaemia was induced by cross-clamping of the aorta. The hearts were removed and incubated at 35 degrees C. At predetermined times two sections of ventricular myocardium were taken, one of which was then stained with NBT, the other being left unstained. Evaluation of the reflectance spectra from stained sections during the first phase of ischaemia showed a slight loss of NBT colour intensity followed by a more rapid loss of staining until the values of the unstained sections were reached. In contrast to the conventional visual evaluation, the method provides quantitative data on the intensity of staining, and allows use of the NBT technique for statistical evaluation of what happens over time, and the regional distribution of ischaemic injury of tissue. This method may also be applied to other staining techniques.


Assuntos
Doença das Coronárias/patologia , Nitroazul de Tetrazólio , Espectrofotometria/instrumentação , Coloração e Rotulagem , Animais , Tecnologia de Fibra Óptica , Ovinos
14.
Biomed Tech (Berl) ; 36(4): 70-7, 1991 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-1854905

RESUMO

Ischemia causes changes in organ tissue (e.g. during operation or transplantation) which may finally lead to irreversible injury, so that the organ can no longer be resuscitated. To the extent that these changes affect the electrical properties of the tissue they are manifested in the impedance spectrum. As an example, the course of impedance of a HTK-protected porcine liver is presented in the frequency range of 0.1 Hz to 10 MHz, which includes two dispersion--alpha- and beta-dispersion. Using a suitable electrical equivalent circuit analogue to the structure of the liver, the behavior of the alpha- and beta-dispersion is explained on the basis of gap junction closure and narrowing of the extracellular space due to cell swelling.


Assuntos
Sobrevivência de Enxerto/fisiologia , Transplante de Fígado/fisiologia , Potenciais da Membrana/fisiologia , Preservação de Órgãos/métodos , Consumo de Oxigênio/fisiologia , Animais , Espaço Extracelular/fisiologia , Modelos Biológicos , Suínos
15.
Acta Anat (Basel) ; 142(4): 321-5, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1801525

RESUMO

The interstitial space, separated into tissue clefts and interstitium within bundles of myocytes of left canine ventricle, was investigated qualitatively and morphometrically after using different methods of fixation following aortic cross clamping and 10 min of ischemia at 5 degrees C. In frozen sections, the size of tissue clefts is significantly lower than in semithin sections after immersion fixation. The interstitium within bundles of myocytes shows similar values independent of the fixation technique (r = 0.83). This constancy permits a free choice between the two fixation techniques, there being no loss of information from the material investigated.


Assuntos
Matriz Extracelular/ultraestrutura , Miocárdio/citologia , Animais , Criopreservação/métodos , Cães , Fixadores , Ventrículos do Coração/citologia , Microscopia/métodos
16.
Artigo em Inglês | MEDLINE | ID: mdl-1899164

RESUMO

During open heart surgery, reperfusion-induced arrhythmias arising after short periods of ischaemia may originate from subendocardial Purkinje fibres. We investigated the ultrastructure of these fibres during 30 min of global ischaemia at 25 degrees C. The effects both with myocardial protection (HTK cardioplegia) and without it (pure ischaemia) were compared qualitatively and morphometrically. After 30 min pure ischaemia overcontraction of sarcomeres, hypercontraction and contraction bands, together with considerable changes in organelles, predominate over cellular oedema. In Purkinje fibres, both cellular and mitochondrial swelling were significantly increased within this 30-min time period from the onset of pure ischaemia. In contrast, following HTK cardioplegia and 30 min ischaemia, cellular and mitochondrial swelling remain moderate and over-contractions are almost entirely lacking. This means that despite remarkable differences between pure ischaemia and HTK cardioplegia in the degree of protection attained it is clear that, compared with the working myocardium, subendocardial Purkinje fibres do not display a higher resistance to early global ischaemia. Further investigations of this sensitivity of Purkinje fibres to global ischaemia and certain drugs may bring about new insights into myocardial protection and pharmacotherapy of arrhythmias.


Assuntos
Doença das Coronárias/patologia , Miocárdio/ultraestrutura , Ramos Subendocárdicos/ultraestrutura , Animais , Cães , Endocárdio/patologia , Endocárdio/ultraestrutura , Parada Cardíaca Induzida , Miocárdio/patologia , Ramos Subendocárdicos/patologia
17.
Z Gastroenterol ; 29(1): 22-30, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1905443

RESUMO

In order to further corroborate the recent findings on liver ischemia after perfusion with solutions containing an additive of heptanol, that the intraischemic loss of cell-to-cell communication in protected livers can be detected by electrical impedance measurement (1), we tried to induce uncoupling in porcine liver by tissue acidification applying acidified protective solutions. Moreover, the effects of preischemic inhaling of high concentrations of the decoupling anesthetic halothane were examined in unprotected ischemic livers (2-5). Electrical impedance, biochemical analyses, and pH measurements were applied in parallel. In addition, typical time courses of impedance parameters of unprotected liver and skeletal muscle were compared, because the latter is devoid of gap junctions. In spite of overlapping side-effects of the respective uncoupling measure, the results suggest that the loss of cell-to-cell communication in the liver is associated with measureable effects on the electrical impedance.


Assuntos
Equilíbrio Ácido-Base/efeitos dos fármacos , Halotano/farmacologia , Testes de Função Hepática , Fígado/irrigação sanguínea , Potenciais da Membrana/efeitos dos fármacos , Preservação de Órgãos/métodos , Alanina/metabolismo , Animais , Feminino , Glucose/farmacologia , Glicerol/metabolismo , Concentração de Íons de Hidrogênio , Lactatos/metabolismo , Ácido Láctico , Glicogênio Hepático/metabolismo , Manitol/farmacologia , Cloreto de Potássio/farmacologia , Procaína/farmacologia , Suínos
18.
Res Exp Med (Berl) ; 191(3): 155-65, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1925066

RESUMO

The influence of glycogen content, temperature, and Euro Collins (EC) solution on membrane potential (Vm) and intracellular sodium activity (aNai) were measured in cells of superfused porcine liver slices by means of double-barrelled ion-sensitive microelectrodes. Vm was -26.1mV in fasted pigs and -20.6mV after glucose feeding, when measured in HEPES-buffered solution (P less than 0.0001). aNai was not measurably affected by glucose feeding. During superfusion with Tyrode solution, lowering the temperature from 35.5 degrees C to 15.5 degrees C led to a fast Vm decrease of roughly 2mV followed by an increase of 1-3mV. At the same time, aNai increased from 12.8 to 18.2mM within 10 min. Superfusion with EC solution for 10 min caused comparable changes in fed and fasted pigs. Vm depolarized at either temperature by about 16mV. At 35.5 degrees C the initial aNai of 17.5mM was roughly halved, whereas at 15.5 degrees C it decreased from 21.0 to 14.3mM. The results suggest that the nutritional state markedly affects the electric properties of liver. However, the effect on membrane potential of high-potassium organ-protective solutions seems to be distinctly more pronounced. Moreover, cellular Na+ activity decreases in consequence of an extracellular Na+ reduction with protective solutions, which might be balanced to some extent by a simultaneous temperature decrease.


Assuntos
Glicogênio Hepático/metabolismo , Fígado/metabolismo , Sódio/metabolismo , Animais , Jejum , Feminino , Glucose/administração & dosagem , Soluções Hipertônicas , Técnicas In Vitro , Masculino , Potenciais da Membrana , Preservação de Órgãos , Perfusão , Ratos , Suínos , Temperatura
19.
Z Gastroenterol ; 28(12): 665-72, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2087822

RESUMO

Heptanol, an agent known for inducing closure of gap junctions in a variety of organs, was used to evaluate the influence of uncoupling on the electrical impedance of livers during ischemia. Heptanol was added to a modified HTK solution or to Belzer's UW-CSS solution. Livers of swine were then perfused for 8 min with either one of the solutions containing heptanol or a solution devoid of this additive. During the following ischemia the phase angle of impedance at 5 kHz, pH and different biochemical parameters were determined. Heptanol fundamentally changed the time course of impedance and made the otherwise characteristic fast increase of the phase angle of impedance disappear. Already early during ischemia the phase angle was raised in a dose-dependent manner up to even highest values at the beginning of the whole observation period in case of a fully developed effect. Heptanol also stimulated anaerobic energy turnover. The results suggest that, besides unspecific effects, heptanol induces uncoupling which is detectable by electrical impedance measurement.


Assuntos
Álcoois/farmacologia , Isquemia/fisiopatologia , Fígado/irrigação sanguínea , Preservação de Órgãos/métodos , Animais , Heptanol , Potenciais da Membrana/efeitos dos fármacos , Perfusão , Suínos
20.
Helv Chir Acta ; 57(3): 435-8, 1990 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-2269626

RESUMO

Imperative indications for organ-sparing surgery of renal tumors are given mainly in existing or imminent restriction of renal function. Organ-sparing excision of renal tumors under in-situ protection with HTK-solution compared with operations without protection have the following advantages: 1. reduced blood loss, 2. longer ischemia, 3. better tissue differentiation with benefit for radicality, 4. shorter hospital stay.


Assuntos
Soluções Cardioplégicas/uso terapêutico , Neoplasias Renais/cirurgia , Humanos , Procedimentos Cirúrgicos Operatórios/métodos
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