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1.
Zentralbl Chir ; 142(1): 46-53, 2017 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-27672739

RESUMEN

Introduction: Practical clinical expertise is a crucial part of medical professionalism. Several studies have shown that medical students are poorly trained in practical skills during their undergraduate training. Even the students rated their own expertise in practical skills as poor. The amendments to the German Regulating Licenses in Practical Medicine are intended to strengthen practical clinical training. The aim of the present study is to use focus groups to analyse practical clinical training with respect to organisation, difficulties and problems from the learners' perspective. Methods: The present qualitative study uses the focus group approach. Each focus group was composed of a maximum of 6 students per group with the same level of training. Using a standardised interview manual, a total of 31 students and four first-year residents participated in the study. Data interpretation was performed using structured qualitative content analysis. Results: The present work demonstrates that students of all levels of training greatly value their training in practical clinical expertise, especially in clinical skills. Due to the lack of defined learning objectives for practical skills, students training in clinical internships and medical registrar positions are highly dependent on the motivation and interest of the individual clinical teacher and the learner himself. Students struggle to estimate their actual level of expertise due to the lack of defined learning objectives. This is exacerbated by the fact that students rarely receive feedback about their expertise. Students complain that many teachers do not know the level of training required of their students. Conclusion: The definition of basic and specific learning objectives and the communication of this between learners and teachers is an essential part of practical clinical training.


Asunto(s)
Actitud del Personal de Salud , Cirugía General/educación , Preceptoría , Estudiantes de Medicina/psicología , Enseñanza , Adulto , Competencia Clínica/normas , Curriculum/normas , Femenino , Grupos Focales , Humanos , Masculino , Persona de Mediana Edad , Asistentes Médicos/educación , Asistentes Médicos/psicología , Asistentes Médicos/normas , Preceptoría/normas , Investigación Cualitativa
2.
Chirurg ; 84(10): 869-74, 2013 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-24018916

RESUMEN

BACKGROUND: For competency-oriented teaching in surgery a comprehensive medical educational training and professionalization of clinical teachers is essential. The Surgical Working Group for Teaching has therefore set itself the task of developing an appropriate training concept. METHOD: In the first step the core group took stock of the most relevant educational barriers in the clinical environment. Taking into account these findings a trimodular course was devised that addressed both previous knowledge and different clinical functions of the faculty as well as modern concepts of competency-based academic teaching. RESULTS: The A course is designed for medical teaching of novices with a focus on collation of the medical history, clinical examination and teaching of practical skills. The B course is devised for experienced clinicians and should qualify them for competency-based teaching in complex educational scenarios, such as the operating room or ward rounds, while the C course is directed to a group of persons entrusted with the organization and administration of clinical teaching.


Asunto(s)
Educación Basada en Competencias/organización & administración , Curriculum , Cirugía General/educación , Modelos Educacionales , Sociedades Médicas , Competencia Clínica , Educación Basada en Competencias/métodos , Docentes Médicos , Alemania , Humanos
4.
Chirurg ; 84(4): 277-85, 2013 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-23494054

RESUMEN

Competency-based medical education is a prerequisite to prepare students for the medical profession. A mandatory professional qualification framework is a milestone towards this aim. The National Competency-based Catalogue of Learning Objectives for Undergraduate Medical Education (NKLM) of the German Medical Faculty Association (MFT) and the German Medical Association will constitute a basis for a core curriculum of undergraduate medical training. The Surgical Working Group on Medical Education (CAL) of the German Association of Surgeons (DGCH) aims at formulating a competency-based catalogue of learning objectives for surgical undergraduate training to bridge the gap between the NKLM and the learning objectives of individual medical faculties. This is intended to enhance the prominence and visibility of the surgical discipline in the context of medical education. On the basis of different faculty catalogues of learning objectives, the catalogue of learning objectives of the German Association of Orthopedics and Orthopedic Surgery and the Swiss Catalogue of Learning Objectives representatives of all German Surgical Associations cooperated towards a structured selection process of learning objectives and the definition of levels and areas of competencies. After completion the catalogue of learning objectives will be available online on the webpage of the DGCH.


Asunto(s)
Competencia Clínica/normas , Educación Basada en Competencias/normas , Educación de Pregrado en Medicina/normas , Cirugía General/educación , Catálogos como Asunto , Curriculum/normas , Docentes Médicos , Alemania , Humanos , Ortopedia/educación , Sociedades Médicas
5.
Eur J Vasc Endovasc Surg ; 38(4): 456-62, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19564122

RESUMEN

OBJECTIVES: This study aims to evaluate the feasibility of external polyester scaffolding in infrainguinal bypass grafting when available vein material is suboptimal due to varicosity or dilatation. Primary objectives were short-term primary patency, assisted primary patency and secondary patency. Secondary objectives were to assess the rate of graft stenoses, infections and other adverse effects related to the use of external scaffolding. MATERIALS AND METHODS: A total of 50 consecutive patients were included in this prospective, multicentre, feasibility study from six centres. The indication for infrainguinal bypass was critical limb ischaemia (64%), severe claudication (34%) or popliteal aneurysm (2%). Indications for the use of the external scaffolding were varicosity of the vein graft, ectatic vein graft or the use of spliced vein grafts with segments of widely differing diameters. Duplex scanning of the graft was done perioperatively and at follow-up visits at 1, 3, 6 and 12 months after operation. RESULTS: Primary patency, assisted primary patency and secondary patency at 6 months were 82.3% (+/-SE 6.2%), 88.6% (+/-SE 4.8%) and 92.1% (+/-SE 4.4%), respectively. Six graft stenoses were detected in duplex surveillance. There were no infections related to polyester mesh. CONCLUSIONS: External scaffolding of infrainguinal vein grafts may be a promising innovation. Early results from this multicentre study show that polyester mesh is safe and feasible adjunct to peripheral revascularization enabling the use of otherwise non-optimal vein grafts with acceptable short-term patency.


Asunto(s)
Extremidad Inferior/irrigación sanguínea , Enfermedades Vasculares Periféricas/cirugía , Poliésteres , Mallas Quirúrgicas , Procedimientos Quirúrgicos Vasculares/instrumentación , Venas/trasplante , Adulto , Anciano , Anciano de 80 o más Años , Aneurisma/cirugía , Diseño de Equipo , Estudios de Factibilidad , Femenino , Oclusión de Injerto Vascular/etiología , Oclusión de Injerto Vascular/cirugía , Humanos , Claudicación Intermitente/etiología , Claudicación Intermitente/cirugía , Isquemia/etiología , Isquemia/cirugía , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/complicaciones , Enfermedades Vasculares Periféricas/diagnóstico , Enfermedades Vasculares Periféricas/fisiopatología , Flebografía , Proyectos Piloto , Arteria Poplítea/cirugía , Estudios Prospectivos , Reoperación , Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/cirugía , Factores de Tiempo , Resultado del Tratamiento , Ultrasonografía Doppler Dúplex , Grado de Desobstrucción Vascular , Procedimientos Quirúrgicos Vasculares/efectos adversos , Venas/patología
6.
Hamostaseologie ; 24(3): 151-6, 2004 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-15314698

RESUMEN

A screening program for infrarenal abdominal aortic aneurysm (AAA) has limited cost-effectiveness. Yet, screening of the subpopulation of smoking men aged 60-75 years, or men and smoking women with a family history of vascular diseases or other cardio-vascular co-morbidity is cost-effective and has been demonstrated. It is suited to halve the increasing mortality of AAA. Elective repair of AAA is justified at diameters larger than 5.5 cm for men, but uncertain for women. However, aortic diameters between 4.5 and 5 cm in women probably necessitate an invasive approach. Surveillance of patients who still not meet these criteria should not only include the absolute diameter of the aneurysm, but direct individuals with aneurysms at an annual expansion rate of more than 0.5 cm to elective repair.


Asunto(s)
Aneurisma de la Aorta Abdominal/epidemiología , Animales , Aneurisma de la Aorta Abdominal/diagnóstico , Aneurisma de la Aorta Abdominal/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Caracteres Sexuales , Fumar
7.
Eur J Vasc Endovasc Surg ; 24(2): 166-75, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12389241

RESUMEN

OBJECTIVE: Accelerated re-endothelialisation may inhibit the development of restenosis. Basic Fibroblast Growth Factor (bFGF) plays a key role for early proliferative activity in the artery following injury. Therefore, this study was devised to examine the effect of photodynamic therapy (PDT) on post-injury re-endothelialisation in vivo, and bFGF-mRNA expression in endothelial cells (EC) in vitro. MATERIALS AND METHODS: Rat carotid arteries were balloon-injured prior to PDT. Arteries were analysed after 1, 3, 5, 14 and 30 days. Morphometric measurements were undertaken following injection of 0.5% Evans Blue which stains non-endothelialised surfaces only. To identify EC, immunohistochemistry (CD-31) was performed. Proliferation was assessed by fluorescence cell counting. PCR quantification of bFGF-mRNA expression and proliferation were assessed in bovine aortic EC which were plated on isolated, PDT-treated EC-derived extracellular matrix at (12), 24, 48 (72 h). RESULTS: Three days following PDT, arteries displayed significantly increased endothelial lining (p = 0.02), which was more pronounced at 5 (p = 0.03) and 14 days (p = 0.02). At 30 days no relevant differences between PDT and control were noted. EC proliferation on PDT-treated matrix was significantly increased at 24, 48, and 72 h (p = 0.0004), whereas bFGF-mRNA expression was significantly increased at 24 h only (p = 0.007). CONCLUSION: Post-injury PDT appears to accelerate re-endothelialisation. Expression of bFGF-mRNA, however, although increased shortly after PDT, may not be responsible for a constant stimulation of EC proliferation.


Asunto(s)
Reestenosis Coronaria/prevención & control , Reestenosis Coronaria/fisiopatología , Endotelio Vascular/lesiones , Endotelio Vascular/efectos de la radiación , Factor 2 de Crecimiento de Fibroblastos/farmacología , Expresión Génica/efectos de los fármacos , Expresión Génica/efectos de la radiación , Fotoquimioterapia , ARN Mensajero/efectos de los fármacos , ARN Mensajero/efectos de la radiación , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/efectos de la radiación , Animales , Arterias Carótidas/efectos de los fármacos , Arterias Carótidas/fisiopatología , Arterias Carótidas/efectos de la radiación , Traumatismos de las Arterias Carótidas/fisiopatología , Traumatismos de las Arterias Carótidas/terapia , Reestenosis Coronaria/genética , Modelos Animales de Enfermedad , Endotelio Vascular/fisiopatología , Factor 2 de Crecimiento de Fibroblastos/genética , Expresión Génica/genética , Técnicas In Vitro , ARN Mensajero/genética , Ratas , Ratas Sprague-Dawley , Factores de Tiempo , Cicatrización de Heridas/fisiología
8.
J Vasc Surg ; 31(6): 1168-77, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10842154

RESUMEN

PURPOSE: Photodynamic therapy (PDT), the light activation of photosensitizers to produce free radicals, is known to inhibit experimental intimal hyperplasia (IH). However, its clinical application has been limited by the lack of a suitable approach and a clinically appropriate photosensitizer. The aim of this study was to determine the effectiveness of a clinical approach for PDT, while testing its ability to favorably modulate the vascular wound healing response. METHODS: Rat carotid arteries were balloon-injured (BI), and for PDT, the arteries were irradiated with thermoneutral laser light (lambda = 660 nm, 100 J/cm(2)) after the photosensitizer methylene blue (MB) was delivered locally. Control rats included BI alone and MB after BI alone. Arteries were analyzed after 2 weeks with morphometric evaluation (n = 6) and in situ hybridization for versican and procollagen type I gene expression (digitized image pixel analyses, n = 3). RESULTS: No IH developed in PDT-treated arteries (0 +/- 0 mm(2); compared with BI, 0.192 +/- 0.006 mm(2); P <.0001). The diameters remained unchanged (PDT, 0.95 +/- 0.04 mm; BI, 0.94 +/- 0.05 mm; uninjured artery, 0.91 +/- 0.06 mm). Arterial injury resulted in an increase of versican and procollagen type I messenger RNA (mRNA) in the adventitia and neointima. In the repopulating cells of the adventitia after PDT, there was a significant decrease in versican mRNA (% of positive pixels per high-power field: PDT, 1.13% +/- 0.39%; BI, 2.93% +/- 0.61%; P <.02), but not in procollagen type I mRNA. CONCLUSION: The decrease of versican mRNA expression of repopulating cells after PDT reflects favorable healing on a molecular level. Site-specific delivery of MB, a clinically appropriate photosensitizer, followed by PDT represents a suitable method to promote favorable healing after balloon intervention and further supports its role for inhibiting postinterventional restenosis.


Asunto(s)
Arterias Carótidas/efectos de los fármacos , Cateterismo/efectos adversos , Azul de Metileno/uso terapéutico , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Análisis de Varianza , Animales , Arterias Carótidas/patología , Proteoglicanos Tipo Condroitín Sulfato/genética , Tejido Elástico/efectos de los fármacos , Tejido Elástico/patología , Regulación de la Expresión Génica , Hiperplasia , Procesamiento de Imagen Asistido por Computador , Hibridación in Situ , Rayos Láser , Lectinas/genética , Lectinas Tipo C , Masculino , Procolágeno/genética , Proteoglicanos/genética , ARN Mensajero/genética , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Túnica Íntima/efectos de los fármacos , Túnica Íntima/patología , Versicanos , Cicatrización de Heridas
9.
Zentralbl Chir ; 123(12): 1334-9, 1998.
Artículo en Alemán | MEDLINE | ID: mdl-10063541

RESUMEN

During the last 4 years (11/93-11/97) 330 patients with acute bowel obstruction were treated and analysed retrospectively. 80% of the obstructions (n = 265) were in the small bowel and 20% (n = 65) in the large bowel localized. Adhesions were the main cause in 65.7% (n = 174) of all small bowel obstructions, and one third (35.1%, n = 61) of these patients were treated conservatively. In the large bowel, however, 37% were caused by obstructing colon carcinoma mainly localized in the rectosigmoid region. Mechanical bowel obstruction remains to be one of the most common emergencies in general surgery. A successful treatment is based on a rapid and correct diagnosis followed by an immediate surgical intervention if indicated. There are no reliable clinical, laboratory or radiological signs of bowel strangulation available. Preoperative diagnostic examinations should confirm bowel obstruction, determine its localization and origin and exclude other pathologies. Furthermore, it should help in selecting a patient subgroup with small bowel obstruction due to adhesions, which might be treated conservatively. Preoperative diagnostic procedures include case history, clinical examination, basic laboratory tests and a plain abdominal x-ray. In patients with suspected small bowel obstruction due to adhesions without any signs of strangulation a contrast medium follow-through study may be indicated. If the contrast medium fails to pass into the colon within 5 hours, a surgical exploration is recommended. In large bowel obstruction a contrast medium enema, a computed tomography or a colonoscopy are valuable diagnostic tools.


Asunto(s)
Obstrucción Intestinal/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Femenino , Humanos , Obstrucción Intestinal/etiología , Obstrucción Intestinal/cirugía , Intestino Grueso/cirugía , Intestino Delgado/cirugía , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
10.
Lasers Surg Med ; 23(5): 263-73, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9888322

RESUMEN

BACKGROUND: Photodynamic therapy (PDT), the light activation of photosensitizer dyes for the production of free radicals, effectively inhibits experimental intimal hyperplasia with systemic administration of the photosensitizer. The local application of the photosensitizer directly into a vascular lesion to avoid systemic side effects and tightly control dose administration has theoretical appeal. The aim of this study was to quantify serum and arterial tissue uptake after site-specific photosensitizer delivery and, following PDT, determine its effectiveness at inhibiting intimal hyperplasia. STUDY DESIGN/MATERIALS AND METHODS: The rat common carotid artery was balloon-injured, pressurized at 400 mm Hg for 2 minutes with the photosensitizer dye benzoporphyrin-derivative (BPD), and irradiated with 690 nm laser light at a fluence of 100 J/cm2. Control animals were pressurized with saline only, or received no additional treatment than balloon-injury. RESULTS: Pressurization with BPD resulted in complete penetration of the intima and media and was associated with relatively high tissue, but almost no detectable serum BPD concentrations. No skin photosensitization or other systemic side effects were observed with photosensitizer administration. After 9 days, PDT-treated arteries displayed a significantly lower number of smooth muscle cells in the arterial wall than balloon-injured (P < 0.001) or saline-pressurized arteries (P < 0.0002), and no intimal hyperplasia. At 21 days, IH after PDT was significantly reduced as compared with balloon-injured (P < 0.0004), or saline-pressurized arteries (P < 0.003) with no arterial dilatation. CONCLUSIONS: Site-specific delivery of liposomal BPD followed by PDT represents a safe method to treat arteries, and may be effectively used in vivo to inhibit the development of intimal hyperplasia.


Asunto(s)
Arterias Carótidas/efectos de los fármacos , Arterias Carótidas/patología , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/administración & dosificación , Porfirinas/administración & dosificación , Túnica Íntima/efectos de los fármacos , Túnica Íntima/patología , Animales , Arterias Carótidas/metabolismo , Evaluación Preclínica de Medicamentos , Hiperplasia/tratamiento farmacológico , Hiperplasia/metabolismo , Hiperplasia/patología , Inmunohistoquímica , Inyecciones Intralesiones/métodos , Terapia por Láser , Masculino , Fármacos Fotosensibilizantes/farmacocinética , Porfirinas/farmacocinética , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Túnica Íntima/metabolismo , Verteporfina
11.
J Vasc Surg ; 26(2): 294-301, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9279318

RESUMEN

PURPOSE: Photodynamic therapy (PDT), the light activation of photosensitizer dyes for the production of oxygen and other free radical moieties without the generation of heat, has been shown to inhibit the development of experimentally induced intimal hyperplasia. The host response to PDT, a form of vascular injury that results in complete vascular wall cell eradication, is devoid of inflammation and proliferation and promotes favorable vascular wall healing. These effects do not result in intimal hyperplasia and are suggestive of PDT-induced changes in the extracellular matrix (ECM). As a model to better understand the biologic consequences of PDT on the vascular wall matrix proteins, the effect of PDT was studied on the powerful matrix-resident mitogen basic fibroblast factor (bFGF) in vitro. METHODS: PDT (5 to 200 J/cm2, 100 mW/cm2, 675 nm) was used with the photosensitizer chloroaluminum sulfonated phthalocyanine (5 micrograms/ml) to inactivate bFGF in vitro while 100 J/cm2 of irradiation was administered 24 hours after 5 mg/ml of the photosensitizer was used in vivo. PDT was used on bFGF in solution and on endothelial cell-derived ECM. Enzyme-linked immunosorbent assay was used to quantitate bFGF in solution after PDT treatment or after extraction from the ECM by collagenase and heparin. Functional activity of matrix-associated bFGF was assessed by smooth muscle cell mitogenesis by 3H-thymidine incorporation. To demonstrate the in vivo relevance of these observations, immunohistochemical analysis of PDT-treated rat carotid arteries was undertaken. RESULTS: PDT eliminated detectable levels of bFGF in solution. PDT of ECM significantly reduced matrix-bound bFGF (1.0 +/- 0.6 vs 27.5 +/- 1.3 pg/ml; p < 0.0001). This reduction in bFGF after PDT of the ECM was associated with a decrease in vascular smooth muscle cell mitogenesis (52.4% +/- 4.6%; p < 0.0001) when plated on PDT-treated matrix compared with nontreated matrix. Quantitative replenishment of exogenous bFGF to PDT-treated matrix restored proliferation to baseline levels. PDT of rat carotid arteries demonstrated a loss of bFGF staining compared with control nontreated arteries. CONCLUSIONS: PDT inactivation of matrix-resident bFGF and possibly other bioactive molecules can provide a mechanism by which PDT suppresses smooth muscle cell proliferation in the vessel wall. This free radical-mediated alteration of matrix may contribute to favorable vascular healing when PDT is used for the inhibition of injury-induced intimal hyperplasia.


Asunto(s)
Matriz Extracelular/metabolismo , Factor 2 de Crecimiento de Fibroblastos/fisiología , Músculo Liso Vascular/fisiología , Fotoquimioterapia , Animales , Anticuerpos Monoclonales , Aorta/citología , Bovinos , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Ratas , Ratas Sprague-Dawley
12.
Ann Thorac Surg ; 63(5): 1461-3, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9146346

RESUMEN

Primary malignant melanoma of the esophagus is an extremely rare tumor. In the absence of prospectively sampled data in the literature, the following case report and review of the literature indicate that surgical resection of the primary tumor and solitary metastases provides the longest survival times and, to date, is the treatment of choice.


Asunto(s)
Neoplasias Esofágicas/cirugía , Melanoma/cirugía , Anciano , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/patología , Humanos , Masculino , Melanoma/diagnóstico por imagen , Melanoma/patología , Tomografía Computarizada por Rayos X
13.
Lab Invest ; 76(2): 257-66, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9042162

RESUMEN

Photodynamic therapy (PDT), the production of cytotoxic free-radical moieties by light activation of photosensitizer dyes, is a novel approach to inhibit experimental intimal hyperplasia. Local eradication of vascular cells with this method in vivo is followed by expedient reendothelialization, and PDT of extracellular matrix (ECM) in vitro stimulates endothelial cell (EC) growth. This in vitro study explored one possible mechanism underlying these findings by investigating the effects of PDT on matrix-associated transforming growth factor-beta (TGF-beta), a potent inhibitor of EC growth. The ECM deposited by EC on tissue culture plates contained 85.4 +/- 10.2 pg/10 cm2 of TGF-beta, as measured by an ELISA. In contrast, after PDT of ECM, levels of TGF-beta could be barely be detected (0.2 +/- 0.5 pg/10 cm2). The functional consequence of this observation was demonstrated by the finding that PD1 of plates coated with a fibronectin-TGF-beta complex stimulated EC mitogenesis (102.3% +/- 19.3%, p < 0.0005) compared with the untreated control (44.1% +/- 13.5%). The inhibitory effect of ECM-associated TGF-beta on EC was further delineated by blocking its activity with a specific antibody. Whereas the antibody did not affect EC mitogenesis or PDT-treated matrix or matrix-free plates (101% +/- 8.8%, 105.6% +/- 9.8%), EC mitogenesis growing on ECM was significantly enhanced (125.9%, 17.5%, p < 0.05). Finally, SDS-PAGE analysis of PDT-treated TGF-beta in solution demonstrated that the PDT-mediated loss of TGF-beta activity was not associated with changes in its molecular weight. These data demonstrate that increased EC proliferation on PDT-treated matrix is, at least in part, mediated by inactivation of TGF-beta. PDT-removal of this EC growth inhibitor in the intima provides a mechanism by which PDT of the vascular wall could potentiate endothelial regrowth, a factor which may promote proper healing and result in the inhibition of intimal hyperplasia.


Asunto(s)
Matriz Extracelular/efectos de los fármacos , Fotoquimioterapia , Factor de Crecimiento Transformador beta/antagonistas & inhibidores , Animales , Bovinos , División Celular , Células Cultivadas , Medios de Cultivo Condicionados/química , Endotelio/citología , Endotelio/efectos de los fármacos , Endotelio/crecimiento & desarrollo , Ensayo de Inmunoadsorción Enzimática , Matriz Extracelular/metabolismo , Indoles/farmacología , Compuestos Organometálicos/farmacología , Fármacos Sensibilizantes a Radiaciones/farmacología , Factor de Crecimiento Transformador beta/análisis
14.
Thorac Cardiovasc Surg ; 44(6): 304-7, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9021908

RESUMEN

Inhalative cigarette smoking is a major risk factor for atherosclerotic disease as well as primary carcinoma of the lung. On that account, this study was performed to determine the prevalence of primary lung cancer on admission in patients scheduled for vascular surgery. All patients presenting to our department for an intervention are screened for lung diseases. If this pretherapeutic examination suggests the existence of a lung tumor further diagnostic procedures are performed. Making use of a prospective computer-assisted patient-documentation system, we analysed incidental findings of lung cancer in those patients admitted for elective surgery. Between Jan. 1st 1990 and October 31st 1994, we electively treated 2214 patients with the diagnosis of vascular stenosis (n = 1711/77.3%) or atherosclerotic aneurysms (n = 503/22.7%) in our department. In 16 of these patients (m:f = 13:3; age 50-72 [mean: 61.1] years) a carcinoma of the lung was detected during preoperative diagnostic procedures, a prevalence of 0.72%. All these patients were smokers, with a daily inhalative nicotine consumption averaging 25 cigarettes per day for a mean of 35 years. 8 patients underwent a surgical (n = 6) or other invasive (n = 2) vascular interventions. In 8 patients no vascular intervention was performed because of the revealed lung carcinoma. The prevalence of lung cancer in a population of vascular patients in the present study is in accord with data of older investigations of high-risk groups. Only 2 out of 16 lung cancers were detected at a prognostically favourable stage. Smokers with symptoms of vascular disease should be carefully examined for signs of lung cancer.


Asunto(s)
Arteriosclerosis/epidemiología , Arteriosclerosis/cirugía , Neoplasias Pulmonares/epidemiología , Anciano , Arteriosclerosis/etiología , Procedimientos Quirúrgicos Electivos , Femenino , Humanos , Neoplasias Pulmonares/etiología , Neoplasias Pulmonares/prevención & control , Masculino , Tamizaje Masivo , Sistemas de Registros Médicos Computarizados , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Fumar/efectos adversos , Fumar/epidemiología
15.
J Vasc Surg ; 23(4): 698-705, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8627908

RESUMEN

PURPOSE: Photodynamic therapy (PDT) has been demonstrated to inhibit experimental intimal hyperplasia and to lead to expedient reendothelialization but negligible repopulation of the vessel media. The mechanism that underlies the differential ingrowth of cells into PDT-treated vessel segments is not understood. Because the extracellular matrix (ECM) is known to modulate specific cell functions, this study was designed to determine whether PDT of isolated ECM affects the function of endothelial cells (ECs) and smooth muscle cells (SMCs). METHODS: PDT of bovine aortic EC-ECM was performed with chloroaluminum sulfonated phthalocyanine and 675-nm laser light. Control specimens included untreated ECM, ECM-free plates, and ECM exposed to either light or photosensitizer only. Cell function was characterized by attachment, proliferation, and migration of ECs or SMCs that were plated onto identically treated matrixes. RESULTS: SMC attachment (86% +/- 0.4% vs 95% +/- 0.4%), proliferation (46% +/- 0.5% vs 100% +/- 1.4%), and migration (40% +/- 1.0% vs 100% +/- 0.9%) were significantly inhibited after PDT of ECM when compared with untreated ECM (all p < 0.001). In contrast, PDT of ECM significantly enhanced EC proliferation (129% +/- 6.2% vs 100% +/- 6.2%; p < 0.03) and migration (118% +/- 2% vs 100% +/- 0.8; p < 0.01), but did not affect attachment. CONCLUSIONS: This report establishes PDT-induced changes in the ECM with a result of inhibition of SMCs and stimulation of EC functions. It provides insight into how PDT-treated arteries can develop favorable EC repopulation without SMC-derived intimal hyperplasia. These findings may help provide a better understanding of the interactions between cells and their immediate environment in vascular remodeling.


Asunto(s)
Endotelio Vascular/efectos de los fármacos , Matriz Extracelular/efectos de los fármacos , Músculo Liso Vascular/efectos de los fármacos , Fotoquimioterapia , Aluminio/farmacología , Animales , Aorta/efectos de los fármacos , Aorta/patología , Bovinos , Adhesión Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Células Cultivadas , Endotelio Vascular/patología , Matriz Extracelular/patología , Radicales Libres/farmacología , Hiperplasia , Indoles/farmacología , Rayos Láser , Músculo Liso Vascular/patología , Compuestos Organometálicos/farmacología , Fármacos Fotosensibilizantes/farmacología , Túnica Íntima/efectos de los fármacos , Túnica Íntima/patología , Túnica Media/efectos de los fármacos , Túnica Media/patología
16.
Eur Surg Res ; 28(1): 26-31, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8682141

RESUMEN

Submucosal tissue oxygen tension (PtO2) was measured in 20 patients with cervical esophagogastrostomy after resection of esophageal carcinoma, using a Clark-type oxygen electrode. The mean gastric baseline PtO2 was 54.6 +/- 10.7 mm Hg. Following ligature of the vasa brevia and the left gastroepiploic artery PtO2 decreased to 45.8 +/- 9.9 mm Hg, ligature of the left gastric artery caused a decrease to 34.2 +/- 9.7 mm Hg and resection of the lesser curvature and pulling up of gastric tube led to 25.5 +/- 9.0 mm Hg. Clinical value and practicability of intraoperative PtO2 measurements could be proven.


Asunto(s)
Anastomosis Quirúrgica , Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/cirugía , Esofagectomía , Oxígeno/análisis , Adulto , Anciano , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
J Vasc Surg ; 21(6): 882-90; discussion 889-90, 1995 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7776467

RESUMEN

PURPOSE: There is no clinically useful therapy for the suppression of vein bypass graft intimal hyperplasia (IH). Photodynamic therapy (PDT), a technique that uses light to activate otherwise biologically inert photosensitizers to produce cytotoxic effects, has been demonstrated to successfully inhibit experimental IH in balloon-injured arteries. The purpose of this study was to investigate the efficacy of PDT as a method to reduce vein graft IH. METHODS: Reversed external jugular vein bypass grafts of the common carotid artery were performed in 28 male Sprague-Dawley rats. The animals received either chloroaluminum sulfonated phthalocyanine (2.5 mg/kg intravenously) 24 hours before the ex vivo irradiation of the vein grafts (VG) with 100 joule/cm2 at 675 nm (PDT VG) or saline solution as control (CON VG). Preharvest bromodeoxyuridine was administered to label proliferating cells. All vein grafts were perfusion fixed within 96 hours for a pilot study or at 2 and 4 weeks for the main study. Histology, immunohistochemistry, and morphometric analysis were performed. RESULTS: There was no acute thrombus formation in the hypocellular PDT VG with occasional platelets but no leukocytes adherent to the luminal surface. Intimal areas of the PDT VG were 18% at 2 weeks and 53% at 4 weeks of the CON VGs (p < 0.05). Medial areas and percent of stenoses were also significantly less in PDT than in CON VG. However, intimal hyperplasia noted in the longitudinal sections within 2 mm of the anastomoses did not demonstrate a difference between PDT and CON VG. Intimal hyperplasia of both PDT and CON VG consisted of smooth muscle cells, verified by immunohistochemistry. Bromodeoxyuridine-labeled cells were more abundant in 2-week than in 4-week specimens, were found most frequently in the intimal areas of the CON VG body, and were equivalent in the anastomoses of PDT VG and CON VG. CONCLUSIONS: These data suggest that PDT of vein grafts suppresses the development of IH in the body of the vein graft but does not affect IH adjacent to the anastomoses. The artery may be the source of proliferating smooth muscle cells that contribute to the anastomotic vein graft IH.


Asunto(s)
Fotoquimioterapia , Túnica Íntima/patología , Venas/trasplante , Anastomosis Quirúrgica , Animales , Plaquetas/patología , Bromodesoxiuridina , Arteria Carótida Común/cirugía , División Celular , Hiperplasia , Indoles/uso terapéutico , Venas Yugulares/patología , Venas Yugulares/trasplante , Masculino , Compuestos Organometálicos/uso terapéutico , Fármacos Sensibilizantes a Radiaciones/uso terapéutico , Ratas , Ratas Sprague-Dawley , Túnica Íntima/efectos de los fármacos , Venas/patología
18.
Chirurg ; 64(12): 1050-2, 1993 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-8119092

RESUMEN

Metastatic cancer to the esophagus is unusual. Breast cancer represents one of the most frequent solid tumors metastasizing to the esophagus. Less than 100 histologically confirmed cases were reported up to now. By suggestion of Laforet the entity of postmastectomy-dysphagia was inaugurated as a syndrome, characterized by dysphagia, occurring many years after mastectomy due to metastatic breast cancer. Surgical therapy by means of esophagectomy and esophagogastrostomy is a safe procedure and can provide a survival time of several years in combination with other therapies due to reliable palliation.


Asunto(s)
Neoplasias de la Mama/cirugía , Carcinoma Adenoide Quístico/secundario , Trastornos de Deglución/cirugía , Neoplasias Esofágicas/secundario , Mastectomía , Complicaciones Posoperatorias/cirugía , Anciano , Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Carcinoma Adenoide Quístico/patología , Carcinoma Adenoide Quístico/radioterapia , Carcinoma Adenoide Quístico/cirugía , Terapia Combinada , Trastornos de Deglución/patología , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Esofagectomía , Femenino , Humanos , Escisión del Ganglio Linfático , Metástasis Linfática , Estadificación de Neoplasias , Complicaciones Posoperatorias/patología , Reoperación
19.
Zentralbl Chir ; 117(6): 311-24, 1992.
Artículo en Alemán | MEDLINE | ID: mdl-1519390

RESUMEN

During the past 10 years, postoperative mortality associated with resection of oesophageal carcinoma has been reduced from 30% to 11%. However, all efforts to improve longterm survival with extensive excisional procedures and adjuvant chemotherapy and radiotherapy have failed. Fifty-three of 100 patients presenting to the surgeon with an oesophageal carcinoma have resectable disease. Six of them will die from postoperative complications and 47 patients will be discharged from the hospital after an average of 3 weeks. Of these patients, 30 will survive the first, 17 th second, and 7 the fifth year. Although in may be possible to further reduce postoperative complications and mortality, the chances of improving the long-term prognosis of patients with oesophageal carcinoma seem small.


Asunto(s)
Neoplasias Esofágicas/cirugía , Complicaciones Posoperatorias/mortalidad , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Europa (Continente)/epidemiología , Estudios de Seguimiento , Humanos , Estadificación de Neoplasias , Sistema de Registros/estadística & datos numéricos , Tasa de Supervivencia
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