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1.
Unfallchirurg ; 121(8): 596-604, 2018 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-29959449

RESUMO

Thoracic trauma can be a life-threatening condition due to the involvement of vital organs, such as the heart, lungs, tracheobronchial tree and the great vessels. A coordinated interdisciplinary management is vital for the survival of the injured person. Modern diagnostic procedures provide an essential basis for the surgical treatment of patients. Surgical treatment principles include insertion of chest drainage, emergency thoracotomy, complex bronchoplastic and vascular reconstructive techniques and cardiac surgical maneuvers. For this reason highly complex surgical procedures are available, which can be effectively and specifically integrated into an interdisciplinary concept. In this review, the most frequent and prognostically relevant conditions, the indicated diagnostics and their significance as well as the surgical treatment principles, are comprehensively presented under consideration of the clinical situation.


Assuntos
Traumatismos Torácicos , Drenagem , Humanos , Pneumotórax , Traumatismos Torácicos/diagnóstico , Traumatismos Torácicos/terapia , Toracotomia , Ferimentos não Penetrantes , Ferimentos Penetrantes
2.
Zentralbl Chir ; 141(3): 323-9, 2016 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-27035568

RESUMO

The role of surgical lung resection following neo-adjuvant radio-chemotherapy (RCT) in patients with locally advanced non-small cell lung cancer (NSCLC) is yet not clearly defined. The aim of our study was to analyze the postoperative survival and to identify relevant prognostic factors. 46 patients underwent curative resections after neo-adjuvant RCT for locally advanced NSCLC (IIIA/IIIB) between February 2008 and February 2015. A retrospective data analysis regarding preoperative regression status, perioperative mortality, postoperative survival, patho-histological remission, relapse pattern and other prognostic factors was performed. A neo-adjuvant RCT with a median radiation dose of 50.4 [range, 45-60] Gy was performed in 44 (96 %) patients. Partial and/or complete regression was observed in 32 (70 %) patients. R0-resection was achieved in 44 (96 %) patients. The 30-day mortality was 4 % and the perioperative morbidity was 37 %. The overall and progression free 5-year survival rate was 47 % and respectively 45 % [in median 58 months]. The 5-year survival rate of 64 % in the "responder"-group was significantly better when compared with 24 % in the "non-responder"-group (p = 0.038). The tri-modality therapy improved the prognosis in patients with locally advanced NSCLC (stage IIIA/IIIB). The complete patho-histological remission is an important prognostic factor for better long term survival. Dividing the patients in "responder" and "non-responder" after neo-adjuvant RCT may have large therapeutically consequences in the future.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Quimiorradioterapia Adjuvante , Terapia Combinada , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Pneumonectomia , Idoso , Biópsia , Broncoscopia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Feminino , Alemanha , Humanos , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Metástase Linfática/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prognóstico , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
3.
Zentralbl Chir ; 139(3): 335-41, 2014 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-24810892

RESUMO

OBJECTIVE: The therapeutic strategies for oligometastatic non-small cell lung cancer have changed over the last decade from palliative to curative intent. The role of surgery in this multimodal treatment in selected patients remains a subject for open discussion. METHODS: Data of 34 patients with one or two metastases treated from January 1998 to January 2013 were retrospectively analysed. RESULTS: The mean age was 59.7 (± 10.1) years. The male vs. female ratio was 20 vs. 14. Adenocarcinoma was the most common histological type (58.8 %). The synchronous metastases were present in 15 patients, the metachronous in 19 patients. Single metastases were present in 27 patients, two metastases in 7 patients. The most frequently involved organs were brain (58.8 %) and the lungs (23.6 %). The primary tumour resection was achievable in 20 patients as R0 and in 2 patients as R1. The median overall survival, the local and the systemic disease-free survivals in the entire group were 40, 38 and 25 months, respectively. The 5 year overall survival, the 5 year local and systemic disease-free survivals were 29.2, 26.9 and 16.5 %, respectively. The treatment strategies including surgery for primary tumour as well as for pulmonary metastases site, combined with the lymph node dissection and the resection of the extracerebral and cerebral metastases, were identified as independent prognostic factors for long-term survival. CONCLUSION: Surgery in oligometastatic non-small cell lung carcinoma is feasible for primary tumour and for metastases. It is an effective option in the multimodal treatment in highly selected patients. The lymph node dissection should remain an important integral part of the surgical treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/cirurgia , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/patologia , Quimiorradioterapia Adjuvante , Terapia Combinada , Progressão da Doença , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias
4.
Zentralbl Chir ; 138(1): 117-20, 2013 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-23341134

RESUMO

BACKGROUND: The V. A. C. INSTILL® therapy is an innovative process for treating chronic wounds that are not optimally accessible to a systemic antibiotic therapy or infected with multi-resistant pathogens. We report on our first experience and applications of V. A. C. INSTILL® therapy in the field of septic thoracic surgery. MATERIALS AND METHODS: V. A. C. INSTILL therapy was used in 11 cases between 11/2009 and 01/2012. Three patients had sternum osteomyelitis (2 MRSA, 1 Finegoldia magna). In 3 patients chronic pleural empyema after lobectomy (1 Streptococcus viridans, 1 mixed infection with MRSA among others) and after pneumectomy (1 MRSA) were detected. In 2 cases there was an acute pleural empyema with extensive phlegmona in the region of the thoracic soft tissues (2 streptococci). In 1 patient a chronic pleural empyema with MRSA infection was treated. Septic arthritis of the sternoclavicular joint with joint destruction and extensive phlegmona in the region of the cervical soft tissues (1 Streptococcus pneumoniae, 1 Staphylococcus aureus) was treated in 2 patients. In all cases instillation of the wound was performed with Lavasept 0.2 %. Swabs of the wound were taken before starting and after ending V. A. C. INSTILL® therapy as well as before wound closure. RESULTS: Mean patient age was 48.8 ± 18.9 years. V. A. C. INSTILL® therapy was performed for 6.5 ± 1.7 days. Instillation time amounted to 21.7 ± 5.7 s. The duration of action was standardised at 18 min in all cases. In 2 cases (1 MESA, 1 finegoldia) the V. A. C. INSTILL® therapy was repeated. In 10 patients a sterile wound status was achieved before secondary wound closure. All wounds underwent secondary closure without recurrence. CONCLUSIONS: Chronic osteomyelitis with MRSA infections as well as chronically infected residual cavities after empyema surgery and extensive phlegmona are possible indications for V. A. C. INSTILL® therapy in order to help eradicating the infection as quickly and as completely as possible.


Assuntos
Infecções Bacterianas/cirurgia , Farmacorresistência Bacteriana Múltipla , Tratamento de Ferimentos com Pressão Negativa/instrumentação , Infecção da Ferida Cirúrgica/cirurgia , Doenças Torácicas/cirurgia , Infecção dos Ferimentos/cirurgia , Artrite Infecciosa/cirurgia , Celulite (Flegmão)/cirurgia , Doença Crônica , Empiema Pleural/cirurgia , Infecções por Bactérias Gram-Positivas/cirurgia , Humanos , Staphylococcus aureus Resistente à Meticilina , Peptostreptococcus , Infecções Pneumocócicas/cirurgia , Pneumonectomia , Reoperação , Infecções Estafilocócicas/cirurgia , Articulação Esternoclavicular , Esternotomia , Infecções Estreptocócicas/cirurgia , Estreptococos Viridans , Cicatrização/fisiologia
5.
Comput Phys Commun ; 183(7): 1481-1490, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23564964

RESUMO

Major histocompatibility proteins share a common overall structure or peptide binding groove. Two binding groove domains, on the same chain for major histocompatibility class I or on two different chains for major histocompatibility class II, contribute to that structure that consists of two α-helices ("wall") and a sheet of eight anti-parallel beta strands ("floor"). Apart from the peptide presented in the groove, the major histocompatibility α-helices play a central role for the interaction with the T cell receptor. This study presents a generalized mathematical approach for the characterization of these helices. We employed polynomials of degree 1 to 7 and splines with 1 to 2 nodes based on polynomials of degree 1 to 7 on the α-helices projected on their principal components. We evaluated all models with a corrected Akaike Information Criterion to determine which model represents the α-helices in the best way without overfitting the data. This method is applicable for both the stationary and the dynamic characterization of α-helices. By deriving differential geometric parameters from these models one obtains a reliable method to characterize and compare α-helices for a broad range of applications. PROGRAM SUMMARY: Program title: MH2c (MH helix curves) Catalogue identifier: AELX_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AELX_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 327 565 No. of bytes in distributed program, including test data, etc.: 17 433 656 Distribution format: tar.gz Programming language: Matlab Computer: Personal computer architectures Operating system: Windows, Linux, Mac (all systems on which Matlab can be installed) RAM: Depends on the trajectory size, min. 1 GB (Matlab) Classification: 2.1, 4.9, 4.14 External routines: Curve Fitting Toolbox and Statistic Toolbox of Matlab Nature of problem: Major histocompatibility (MH) proteins share a similar overall structure. However, identical MH alleles which present different peptides differ by subtle conformational alterations. One hypothesis is that such conformational differences could be another level of T cell regulation. By this software package we present a reliable and systematic way to compare different MH structures to each other. Solution method: We tested several fitting approaches on all available experimental crystal structures of MH to obtain an overall picture of how to describe MH helices. For this purpose we transformed all complexes into the same space and applied splines and polynomials of several degrees to them. To draw a general conclusion which method fits them best we employed the "corrected Akaike Information Criterion". The software is applicable for all kinds of helices of biomolecules. Running time: Depends on the data, for a single stationary structure the runtime should not exceed a few seconds.

6.
J Nanosci Nanotechnol ; 11(6): 4702-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21770095

RESUMO

We report on the synthesis of vanadium oxide nanoparticles using the laser ablation in solution technique. The particles were characterized by dynamic light scattering-DLS, transmission electron microscopy-TEM, X-ray diffraction-XRD, X-ray photoelectron spectroscopy-XPS and UV-Vis optical spectroscopy. The oxide nanoparticles are mainly composed of tetragonal V2O5, a semiconductor with a 2.2 eV band gap. The interaction of the nanoparticles with cysteine, a very important aminoacid present in proteins, was studied. Upon reaction with cysteine, the bandgap of the nanoparticles shifts to the ultraviolet region at 2.87 eV. This color change from yellow to transparent can be used for selective cysteine sensing. Additionally, the intervalence band of the optical absorption spectra shows capability for cysteine sensing in the microM range.


Assuntos
Cisteína/química , Nanopartículas/química , Compostos de Vanádio/química , Cisteína/análise , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Espectrofotometria Ultravioleta , Termodinâmica , Difração de Raios X
7.
Thorac Cardiovasc Surg ; 58(2): 98-101, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20333572

RESUMO

OBJECTIVE: Thoracomyoplasty after prior posterolateral thoracotomy (PLT) remains a challenge for the thoracic surgeon. Thoracodorsal artery division after PLT impairs the vascularization supply of the latissimus dorsi muscle (LDM) resulting in muscle mass reduction due to distal atrophy. This makes adequate filling of residual empyema space and/or surgical closure of bronchial stump insufficiency more difficult, and they require alternative surgical procedures. We present an alternative approach using a four-muscle flap technique to include the infraspinatus, the subscapularis and the teres major muscle group, all pedicled from the subscapular artery as a part of a modified thoracomyoplasty technique for closing residual empyema space and bronchial stump insufficiency. METHODS: Between 2002 and 2008 we performed the technique in 7 patients with residual empyema space. Three patients had post-tuberculosis syndrome, 2 had postpneumectomy empyema, and 2 had chronic parapneumonic empyema. Three cases were combined with a bronchopleural fistula. All patients underwent a two-stage procedure. First, open window thoracostomy was performed followed by definitive surgical treatment after 3-6 months. In all cases with bronchial insufficiency the stump was covered with a subscapularis muscle flap. The infraspinatus and the teres muscle group were used in combination with a local thoracoplasty. RESULTS: Mean age was 68 +/- 7.9 years. Time from open window thoracostomy to thoracomyoplasty averaged 4 +/- 1.3 months. The number of resected ribs ranged between 4 and 8. Mean postoperative stay in the ICU was 3 +/- 2.9 days. The thoracic drains were removed after 5 +/- 2.3 days. Total hospital stay was 15 +/- 7.6 days. No hospital mortality was noted. Minor postoperative complications occurred in 2 cases. Shoulder function without pain allowed abduction up to 90 degrees. Function was decreased by 16 +/- 9 degrees compared to preoperative evaluation. No severe progressive scoliosis was noted. CONCLUSIONS: Division of the LDM and its vascular supply after posterolateral thoracotomy results in a reduction of muscle mass. The shoulder girdle muscles offer an adequate alternative to fill residual empyema space with acceptable long-term results and restriction in shoulder motion. In all cases with bronchial fistula, bronchial stump closure with a pedicled subscapular muscle was an effective alternative operative technique.


Assuntos
Fístula Brônquica/cirurgia , Empiema Pleural/cirurgia , Doenças Pleurais/cirurgia , Fístula do Sistema Respiratório/cirurgia , Retalhos Cirúrgicos , Toracoplastia , Toracostomia , Toracotomia , Idoso , Idoso de 80 Anos ou mais , Fístula Brônquica/complicações , Empiema Pleural/complicações , Humanos , Tempo de Internação , Pessoa de Meia-Idade , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/transplante , Doenças Pleurais/complicações , Fístula do Sistema Respiratório/complicações , Retalhos Cirúrgicos/efeitos adversos , Toracoplastia/efeitos adversos , Toracostomia/efeitos adversos , Toracotomia/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
8.
J Colloid Interface Sci ; 316(2): 510-6, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17900605

RESUMO

In this work we describe the fabrication of FeCo alloy (less than 10 at% Co) thin films from aqueous ammonium sulfate solutions onto n-type Si(111) substrates using potentiostatic electrodeposition at room temperature. The incorporation of Co into the deposits tends to inhibit Fe silicide formation and to protect deposits against oxidation under air exposure. As the incorporation of Co was progressively increased, the sizes of nuclei consisting of FeCo alloy increased, leading to films with a highly oriented body-centered cubic structure with crystalline texture, where (110) planes remain preferentially oriented parallel to the film surface.


Assuntos
Ligas/química , Cobalto/química , Hidrogênio/química , Ferro/química , Membranas Artificiais , Silício/química , Eletroquímica , Magnetismo , Tamanho da Partícula , Sensibilidade e Especificidade , Espectrofotometria/métodos , Espectroscopia de Mossbauer/métodos , Propriedades de Superfície , Difração de Raios X , Raios X
9.
Chirurg ; 88(6): 512-517, 2017 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-27928604

RESUMO

BACKGROUND: There is no evidence from randomized trials on the prognostic significance of pulmonary metastasectomy of colorectal cancer. The objective of this study was to assess the current criteria for indications, preoperative diagnostics and preferred operative techniques of pulmonary metastasectomy in Germany. METHODS: An anonymous survey was carried out in 239 German centers performing thoracic surgery in October 2015. RESULTS: Chest computed tomography (CT, 98%), liver CT (62%), pelvis CT (39%) and fluorodeoxyglucose positron emission tomography (FDG-PET, 37%) were used by the respondents (65% of participants) for preoperative staging. Pulmonary metastasectomy was most commonly performed for solitary lung metastasis without extrathoracic disease (96%), >1 ipsilateral lung metastases without extrathoracic disease (94.8%), solitary lung metastasis with resectable hepatic metastases (92%) and resectable bilateral lung metastases without extrathoracic disease (91%). Of the respondents 95% performed open lung metastasectomy, 82% video-assisted thoracic surgery, 18% radiofrequency ablation, 53% used laser-assisted open resection and 46% indicated that there was no scientific consensus on pulmonary metastasectomy. CONCLUSION: The majority of respondents performed pulmonary metastasectomy for solitary and multiple, unilateral and bilateral lung metastases without extrathoracic disease and/or local recurrence of primary tumors. The coexistence of resectable liver metastases was not an absolute contraindication for surgery. Of the respondents 46% expressed the need for prospective randomized studies to improve the evidence on pulmonary metastasectomy for colorectal cancer.


Assuntos
Neoplasias Colorretais/cirurgia , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/cirurgia , Metastasectomia/métodos , Pneumonectomia/métodos , Neoplasias Colorretais/diagnóstico , Contraindicações , Fluordesoxiglucose F18 , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Neoplasias Pulmonares/diagnóstico , Tomografia por Emissão de Pósitrons , Prognóstico , Inquéritos e Questionários , Tomografia Computadorizada por Raios X , Reino Unido
10.
Cell Biochem Biophys ; 44(3): 503-11, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16679538

RESUMO

The protein GlnB-Hs (GlnB of Herbaspirillum seropedicae) in diazotroph micro-organisms signalizes levels of nitrogen, carbon, and energy for a series of proteins involved in the regulation of expression and control of the activity of nitrogenase complex that converts atmospheric nitrogen in ammonia, resulting in biological nitrogen fixation. Its structure has already been determined by X-ray diffraction, revealing a trimer of (36 kDa) with lateral cavities having hydrophilic boundaries. The interactions of GlnB-Hs with the well-known Si(111) surface were investigated for different incubation times, protein concentrations in initial solution, deposition conditions, and substrate initial state. The protein solution was deposited on Si(111) and dried under controlled conditions. An atomic force microscope operating in dynamic mode shows images of circular, linear, and more complex donut-shaped protein arrangement, and also filament types of organization, which vary from a few nanometers to micrometers. Apparently, the filament formation was favored because of protein surface polarity when in contact with the silicon surface, following some specific orientation. The spin-coating technique was successfully used to obtain more uniform surface covering.


Assuntos
Proteínas de Bactérias/química , Modelos Químicos , Proteínas PII Reguladoras de Nitrogênio/química , Silício/química , Adsorção , Proteínas de Bactérias/ultraestrutura , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos/fisiologia , Bactérias Gram-Negativas/química , Herbaspirillum , Microscopia de Força Atômica/métodos , Nitrogênio/química , Nitrogenase/química , Proteínas PII Reguladoras de Nitrogênio/ultraestrutura , Rhizobiaceae , Soluções , Propriedades de Superfície , Difração de Raios X/métodos
11.
J Gen Physiol ; 109(2): 129-40, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9041443

RESUMO

Models of coronary arterial trees are generated by the algorithm of constrained constructive optimization (CCO). In a given perfusion area a binary branching network of straight cylindrical tubes is generated by successively adding terminal segments to the growing structure. In each step the site of connection is chosen according to an optimization target function (total intravascular volume), and in any stage of development the tree fulfills physiologic boundary conditions (constraints involving pressures, flows and bifurcation rules). CCO generates structures which in many aspects resemble real coronary arterial trees, except for very asymmetric bifurcations, occurring when a large branch gives off a tiny terminal segment. In the present work we evaluate an additional constraint within CCO, namely imposing a limit on the asymmetry of bifurcations during the construction process. Model trees are grown with different limits imposed, and the effects on structure are studied both phenomenologically and via statistical descriptors. As the limit to asymmetry is tightened, blood is conveyed to the perfusion sites via detours rather than directly and the comparison with measured data shows that the structure to change from a conveying to a delivering type of function. Simultaneously total intravascular volume, surface and sum of segments' lengths increase. It is shown why and how local bifurcation asymmetry is able to determine the global structure of the optimized arterial tree model. Surprisingly, the pressure profile from inlet to terminals, being a functional characteristic, remains unaffected.


Assuntos
Vasos Coronários/anatomia & histologia , Algoritmos , Pressão Sanguínea/fisiologia , Simulação por Computador , Circulação Coronária/fisiologia , Vasos Coronários/fisiologia , Modelos Lineares , Modelos Anatômicos , Análise de Regressão , Viscosidade
12.
J Gen Physiol ; 106(4): 583-99, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8576698

RESUMO

The computational method of constrained constructive optimization was used to generate complex arterial model trees by optimization with respect to a target function. Changing the target function also changes the tree structure obtained. For a parameterized family of target functions a series of trees was created, showing visually striking differences in structure that can also be quantified by appropriately chosen numerical indexes. Blood transport path length, pressure profile, and an index for relative segment orientation show clear dependencies on the optimization target, and the nature of changes can be explained on theoretical grounds. The main goal was to display, quantify, and explain the structural changes induced by different optimization target functions.


Assuntos
Artérias/anatomia & histologia , Modelos Cardiovasculares , Animais , Artérias/fisiologia , Pressão Sanguínea , Simulação por Computador , Humanos , Pessoa de Meia-Idade
13.
J Gen Physiol ; 103(6): 975-89, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7931140

RESUMO

The structure of a complex arterial tree model is generated on the computer using the newly developed method of "constrained constructive optimization." The model tree is grown step by step, at each stage of development fulfilling invariant boundary conditions for pressures and flows. The development of structure is governed by adopting minimum volume inside the vessels as target function. The resulting model tree is analyzed regarding the relations between branching angles and segment radii. Results show good agreement with morphometric measurements on corrosion casts of human coronary arteries reported in the literature.


Assuntos
Artérias/anatomia & histologia , Processamento de Imagem Assistida por Computador , Modelos Biológicos , Animais , Humanos , Matemática
14.
J Colloid Interface Sci ; 283(1): 107-12, 2005 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-15694430

RESUMO

Natural chrysotile fibers and pegmatitic phlogopite were acid-leached under controlled conditions. The resulting products were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, (29)Si nuclear magnetic resonance, transmission electron microscopy, and selected area electron diffraction. The leached products derived of the two clays are similar, consisting of layered hydrated disordered silica with a "distorted" structure resembling the silicate layer existing in the original minerals. A simple model of the "disordered" silica structure is presented.

15.
Cardiovasc Res ; 22(4): 265-76, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3197057

RESUMO

The haemodynamic responses to pressure controlled intermittent coronary sinus occlusion (PICSO) were recorded intraoperatively in dogs. After analogue-digital conversion the data for coronary sinus pressure were submitted to numerical analysis for detection of systolic and diastolic envelopes and their subsequent fitting by a non-linear model. From the model variables derived quantities, such as plateau and rise times, were constructed so as to resemble the most important features of coronary sinus pressure rise during each occlusion-release cycle. The derived quantities were then monitored during all consecutive cycles throughout the entire experiment. In each dog the measurements were taken during normal coronary artery perfusion, left anterior descending coronary artery infarction, and reperfusion. The analysis comprise time course, stability, and physiological correlates of the derived quantities, on some of which a closed loop regulation may be based. Predicted plateaus (systolic and diastolic) and mean integrals (systolic and diastolic) were found to be stable quantities which, on subaveraging of about five successive estimates, yielded a 10% accuracy on the mean. By contrast, the rise times required subaveraging of about 15 cycles to achieve the same relative stability. It is concluded that, on subaveraging, derived quantities lend themselves for closed loop regulation input. Thus this quantitative assessment of numerical coronary sinus pressure analysis, as obtained from animal data, may lay the basis for future human application.


Assuntos
Circulação Coronária , Computação Matemática , Modelos Cardiovasculares , Análise Numérica Assistida por Computador , Animais , Pressão Sanguínea , Cães , Hemodinâmica , Métodos
16.
Cardiovasc Res ; 22(4): 277-86, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3264206

RESUMO

Pressure controlled intermittent coronary sinus occlusion (PISCO) was applied in 30 patients undergoing coronary artery bypass surgery. The occlusion and release times were manually adjusted according to visual control of the intraoperatively monitored coronary sinus pressure. In six patients the coronary sinus measurements were additionally digitised with a personal computer before postoperative mathematical analysis, which comprised automatic detection of systolic peaks, diastolic troughs, and the calculation of derived quantities. The purpose of the analysis was (a) to assess quantitatively human coronary sinus pressure dynamics, (b) to determine whether visual control and interpretation of coronary sinus pressure rise could be replaced by a mathematical model, and (c) to ascertain whether the occlusion and release cycle lengths were adequate. Numerical estimates for intraindividual and interindividual spread of calculated quantities were produced, the mathematically obtained results were related to a possible physiological interpretation, and the most efficient method of statistical analysis was ascertained. These results form the numerical basis for a closed loop adjustment of pressure controlled intermittent coronary sinus occlusion cycling.


Assuntos
Circulação Coronária , Idoso , Pressão Sanguínea , Ponte de Artéria Coronária , Humanos , Período Intraoperatório , Masculino , Métodos , Análise Numérica Assistida por Computador
17.
Free Radic Biol Med ; 17(6): 577-85, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7867974

RESUMO

Human umbilical vein endothelial cells were incubated with Bretschneider and St. Thomas II cardioplegic solution followed by a stimulation with cumene hydroperoxide (CHPO), which was used as an oxygen radicals generating agent. A statistically significant decrease of intracellular high energy phosphates (adenosine-5-trisphosphate: ATP; creatine phosphate: CP) compared to controls was observed in response to Bretschneider cardioplegia and CHPO. Furthermore, significant rises in prostaglandin I2 (prostacyclin; PGI2) production and lipidperoxidation were measured. The authors failed to record such alterations of endothelial cell metabolism for the St. Thomas II cardioplegic solution. They could also demonstrate that the cellular protection against oxygen radicals exerted by the St. Thomas II solution is attributable to procaine. The enhanced cytotoxicity of CHPO observed in presence of the Bretschneider solution was found to be partially caused by its constituent L-histidine, which led to significant decreases of high energy phosphates and increased lipidperoxidation when cells were subsequently treated with CHPO. However, alterations of high energy phosphate content initiated by CHPO and amplified by the Bretschneider solution could not be inhibited by adding procaine. Simultaneous pretreatment of cells with the Bretschneider solution and procaine and stimulation with CHPO resulted in decreases of ATP and CP, as observed using the Bretschneider cardioplegia alone.


Assuntos
Soluções Cardioplégicas/farmacologia , Endotélio Vascular/efeitos dos fármacos , Histidina/farmacologia , Procaína/farmacologia , Espécies Reativas de Oxigênio/análise , Trifosfato de Adenosina/análise , Derivados de Benzeno , Soluções Cardioplégicas/química , Células Cultivadas , Epoprostenol/análise , Humanos , Estresse Oxidativo , Fosfocreatina/análise , Temperatura , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Veias Umbilicais
18.
Am J Med ; 98(5): 469-75, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7733126

RESUMO

PURPOSE: To investigate whether serum levels of lipid peroxides measured as thiobarbituric-acid-reactive substances (TBARS) differ in type I and type II diabetic patients, whether serum levels correlate with late sequelae of diabetes, and whether serum levels of free vitamin E correlate with levels of lipid peroxidation by-products. PATIENTS AND METHODS: The relationship among lipids, glycosylated hemoglobin A1c (HbA1c), lipid peroxides measured as TBARS, and free vitamin E was determined in 158 patients. Fifteen of the 77 patients with type I diabetes and 39 of the 81 patients with type II diabetes had clinically apparent peripheral vascular disease or coronary artery disease, or both. RESULTS: Compared with control subjects, serum levels of TBARS were found to be significantly elevated (P < 0.001) in diabetic patients, and type II diabetic patients had significantly higher levels (P < 0.001) than type I patients. Both type I and type II diabetic patients with good metabolic control (HbA1c < 6.5%) had significantly lower (P < 0.005) TBARS levels than patients with poor metabolic control, but all groups had higher levels than the control group. Type II patients with angiopathy had significantly higher levels of TBARS than patients without angiopathy. Free vitamin E levels in control subjects and diabetic patients did not differ statistically. CONCLUSION: Serum levels of TBARS were significantly increased in all patients suffering from diabetes mellitus, whereby TBARS levels did not depend on the total amount of circulating lipids. It can be suggested that the enhanced lipidperoxidation is contributed to an increased formation of free radicals in diabetes mellitus.


Assuntos
Diabetes Mellitus/sangue , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Adulto , Idoso , Complicações do Diabetes , Diabetes Mellitus/metabolismo , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Angiopatias Diabéticas/sangue , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Peroxidação de Lipídeos/fisiologia , Masculino , Pessoa de Meia-Idade , Ácido Úrico/sangue , Vitamina E/sangue
19.
Transplantation ; 60(11): 1245-51, 1995 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8525518

RESUMO

An evaluation of 26 surviving outpatient lung transplant recipients at one center showed that 65% (17/26) had significant anemia (hemoglobin < 11 g/L for women, < 14 g/dl for men) at a median follow-up of 13.5 months after transplantation (range, 1-41 months). There were 14 men and 12 women with a mean age of 45.1 years (range, 23.1-66.7 years). Fifteen had a double allograft and 11 had a single allograft. Anemia was normochromic and normocytic/macrocytic with a tendency to anisocytosis, with normal reticulocyte counts. Iron deficiency (transferrin saturation < 20%) was found in 35% (6/17) of anemic patients, and two of them also had ferritin levels < 15 micrograms/L. In addition, vitamin B12 was decreased in 1 patient. Folate levels were all normal. Erythropoietin levels were significantly decreased in anemic lung transplant recipients as compared with nontransplanted iron-deficient anemic patients (median, 1 mU/ml, range 1-41 mU/ml, vs. 53 mU/ml, 15-88 mU/ml; P < 0.05). In nonanemic lung transplant recipients, erythropoietin levels were decreased too, as compared with normal controls (median, 2 mU/ml, range 1-21 mU/ml, vs. 5 mU/ml, 3-32 mU/ml; P < 0.05). Investigation of peripheral stem cells in 9 patients showed normal stimulation of erythroids (burst-forming unit, erythroid; median, 573 cells/ml; range, 128-1898 cells/ml) independent of erythropoietin concentrations. Analysis of putative prognostic factors, such as age, surgical procedure (double vs. single lung allograft), indication for transplantation, time after transplantation, infection status, presence of bronchiolitis obliterans, immunosuppression (+/- azathioprine), serum creatinine, creatinine clearance, hypertension, and arterial partial pressure of oxygen, did not demonstrate any difference in erythropoietin concentrations. Only the sex variable revealed a trend to higher levels in women than in men (median, 4 mU/ml, range 1-41 mU/ml, vs. 1 mU/ml, 1-16 mU/ml; P > 0.05). The causes for low erythropoietin levels are not quite understood yet; however, they offer a rationale for the treatment of chronic anemia with recombinant human erythropoietin.


Assuntos
Anemia/fisiopatologia , Eritropoetina/sangue , Transplante de Pulmão/efeitos adversos , Adulto , Idoso , Anemia/etiologia , Eritropoese , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida
20.
Thromb Haemost ; 78(3): 1003-7, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9308744

RESUMO

A group of 100 patients with intermittent claudication (70 male, 30 female), treated with I00 mg ASA per day, were followed over 18 months after elective percutaneous balloon angioplasty. Platelet function was monitored over a period of 12 months by corrected whole blood aggregometry (CWBA). Upon stimulation by arachidonic acid (AA), adenosine diphosphate (ADP) and collagen, CWBA-results were obtained by an electronic acquisition and evaluation system correcting for hematocrit and platelet count of the blood sample. All patients showed a completely inhibited platelet response to AA stimulation. Comparison of the CWBA-results with clinical parameters revealed that reocclusions at the site of angioplasty occurred exclusively in male patients for which CWBA failed to prove an inhibition of aggregation upon both agonists, ADP and collagen, and for these patients the risk of complication is at least 87% higher (p = 0.0093). Only 40% of male patients show the expected effect of ASA on in vitro platelet aggregation at any given point in time and CWBA is capable of predicting those male patients which are at an elevated risk of reocclusion following peripheral angioplasty.


Assuntos
Angioplastia com Balão , Arteriopatias Oclusivas/terapia , Aspirina/uso terapêutico , Plaquetas/efeitos dos fármacos , Claudicação Intermitente/terapia , Perna (Membro)/irrigação sanguínea , Inibidores da Agregação Plaquetária/uso terapêutico , Administração Oral , Idoso , Aspirina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/administração & dosagem , Fatores de Risco , Fumar
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