RESUMEN
OBJECTIVES: We sought to determine whether endothelium-derived relaxing factor (nitric oxide) exerts a tonic vasodilating effect on coronary collateral channels developed in response to myocardial ischemia. BACKGROUND: Although the coronary collateral circulation is known to react to several vasoactive agents, the role of endogenously produced nitric oxide is unclear. METHODS: Coronary collateral channels were induced in the left circumflex artery bed of 12 chronically instrumented dogs by either ameroid implantation or repeated occlusion of the left circumflex coronary artery. With the native circumflex artery occluded, aortic and circumflex pressures and microsphere flows were measured before and after systemic administration of NG-nitro-L-arginine methyl ester, an arginine analogue known to block the synthesis of nitric oxide. RESULTS: NG-nitro-L-arginine methyl ester increased mean aortic pressure from a mean +/- SEM of 92 +/- 4 to 114 +/- 4 mm Hg, whereas pressure in the occluded circumflex artery decreased from 61 +/- 4 to 55 +/- 4 mm Hg. The increase in aortic-circumflex pressure gradient (from 31 +/- 4 to 59 +/- 5 mm Hg) was accompanied by a decrease in flow in the circumflex bed (from 1.31 to +/- 0.14 to 1.09 +/- 0.15 ml/min per g), resulting in an increase in coronary collateral resistance averaging 173 +/- 37% (from 26 +/- 4 to 64 +/- 9 mm Hg/ml per min per g, p < 0.01). The increase in collateral resistance could be partially reversed by administration of L-arginine. CONCLUSIONS: We conclude that nitric oxide normally exerts a substantial tonic dilating effect in coronary collateral vessels. Disease-induced alterations in endothelial function may limit collateral perfusion importantly.
Asunto(s)
Circulación Colateral/efectos de los fármacos , Vasos Coronarios/efectos de los fármacos , Isquemia Miocárdica/patología , Óxido Nítrico/fisiología , Animales , Arginina/análogos & derivados , Arginina/farmacología , Dilatación Patológica , Modelos Animales de Enfermedad , Perros , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Masculino , NG-Nitroarginina Metil Éster , Óxido Nítrico Sintasa/antagonistas & inhibidoresRESUMEN
Endocarditis requiring surgical intervention in children is uncommon. Individualized operative therapy must be fashioned to the particular pathology of each case. In this case we describe mitral anterior leaflet homograft patch augmentation valvuloplasty, subaortic homograft patch closure of a large mycotic aneurysm, and homograft aortic root replacement in a 3-year-old patient with endocarditis after remote repair of complete atrioventricular canal.
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Aneurisma Infectado/cirugía , Aneurisma de la Aorta/cirugía , Endocarditis Bacteriana/cirugía , Válvula Mitral/cirugía , Infecciones Neumocócicas/cirugía , Aneurisma Infectado/diagnóstico por imagen , Aorta/cirugía , Aneurisma de la Aorta/diagnóstico por imagen , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Válvula Aórtica/trasplante , Insuficiencia de la Válvula Aórtica/cirugía , Preescolar , Ecocardiografía , Ecocardiografía Transesofágica , Endocarditis Bacteriana/diagnóstico por imagen , Femenino , Humanos , Válvula Mitral/diagnóstico por imagen , Insuficiencia de la Válvula Mitral/cirugía , Infecciones Neumocócicas/diagnóstico por imagen , Trasplante HomólogoRESUMEN
Thoracoscopy can be done safely and effectively through working ports placed in the axilla in patients whose pathology is in the upper half of the thorax. We have used this technique successfully in 37 patients with no complications. Advantages include superior cosmesis, optimal access to the apex of the chest, and, if necessary, easy conversion to axillary thoracotomy.
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Toracoscopía/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Axila , Humanos , Persona de Mediana EdadRESUMEN
Primary lymphoepithelioma-like carcinoma of the lung is rare; only 26 case reports have been identified in the literature. The present report presents a case of a 67-year-old white man with a T1 N1 M0 lymphoepithelioma-like carcinoma of the lung. He presented with severe arthritic complaints that resolved after resection of the tumor. The majority of these tumors have occurred in Asian patients who have shown evidence of previous exposure to the Epstein-Barr virus.
Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Pulmonares/patología , Anciano , Humanos , MasculinoRESUMEN
Surgical treatment of the combination of aneurysms of an aberrant right subclavian artery, distal aortic arch, and descending thoracic aorta requires control of structures in both the right and the left hemithorax. We report a 2-stage surgical approach. The 1st stage, performed through a median sternotomy, consists of an elephant trunk reconstruction and an interposition graft to the ligated aberrant right subclavian artery. The 2nd stage, performed through a left thoracotomy is an interposition graft from the elephant trunk to the distal descending thoracic aorta.
Asunto(s)
Aneurisma/cirugía , Aneurisma de la Aorta Torácica/cirugía , Arteria Subclavia/anomalías , Arteria Subclavia/cirugía , Aneurisma de la Aorta Torácica/complicaciones , Implantación de Prótesis Vascular , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Vasculares/métodosRESUMEN
This report describes a late, near-fatal rupture of a false aneurysm of the right internal mammary artery subsequent to coronary artery bypass grafting. The patient presented to us in shock due to hemorrhaging, 8 weeks after bypass surgery that had been complicated by sternal fracture, dehiscence, and infection. Emergent thoracotomy and suture ligation controlled the hemorrhage. To the best of our knowledge, this is the 1st reported case of late massive hemorrhage caused by injury to an internal mammary artery after sternotomy. The literature is reviewed and discussed.
Asunto(s)
Aneurisma Falso/complicaciones , Aneurisma Roto/etiología , Fracturas Óseas/cirugía , Arterias Mamarias , Esternón/lesiones , Anciano , Aneurisma Falso/diagnóstico , Aneurisma Falso/cirugía , Aneurisma Roto/diagnóstico , Aneurisma Roto/cirugía , Puente de Arteria Coronaria , Estudios de Seguimiento , Fracturas Óseas/complicaciones , Humanos , Masculino , Complicaciones Posoperatorias , Radiografía Torácica , Esternón/cirugía , Tomografía Computarizada por Rayos XRESUMEN
This study estimated the potential effects of pesticide drift on terrestrial ecosystems outside target areas, for the Dutch situation. A series of field trials was conducted to estimate the effects of drift on different species groups at different distances from a treated plot for different categories of pesticide: herbicides, fungicides and insecticides. Measurements of the pesticide drift deposition resulting from standard agricultural practice were used to model deposition outside the treated area. These data were then combined with national statistics on cropland and pesticide use to assess the ecological effects of pesticide drift for the Netherlands as a whole. Three scenarios were considered: the recent past (1998), the present (2005) and an optimised scenario based on 'best available practice' (2010). In the recent past the impact of herbicide drift on sensitive life stages non-target vascular plants is estimated to have exceeded the 50% effect level on 59% of adjacent linear landscape elements such as ditch banks and hedgerows. For the impact of insecticides and fungicides on non-target insects and fungi this 50% effect figure was 29% and 28% of linear elements, respectively. In the present situation, with (narrow) unsprayed buffer zones and other measures in place, these percentages are down to 41% for herbicides, 21% for insecticides and 14% for fungicides. In the optimised scenario, with a greater buffer width of 2.25m for potatoes (compared to 1.50m in 2005) and 1m for other crops (compared to 0.25 and 0.5m in 2005) and 'best available practice', these percentages can be cut to zero. In natural areas located within farming regions the 10% effect level can be reduced from 31% of such areas (1998) to 0% under conditions of 'best available practice'.
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Contaminantes Atmosféricos/toxicidad , Ecosistema , Plaguicidas/toxicidad , Animales , Mariposas Diurnas/efectos de los fármacos , Monitoreo del Ambiente , Hongos/efectos de los fármacos , Hongos/crecimiento & desarrollo , Modelos Teóricos , Países Bajos , Desarrollo de la Planta , Plantas/efectos de los fármacosRESUMEN
The principal conclusion of a workshop in October 2005 at RIVM (Bilthoven, The Netherlands) on the assessment of field studies with pesticides for authorization is that the lack of a definition of acceptability of effects is recognized as a problem by all stakeholders: Industry, risk assessors, and regulators. Because of this lack of definition in the legislation, it is unclear what critical effect values should be assessed in field studies. Despite the extensive documentation on field study performance, the decision making is not based on justifiable scientific opinions or publicly shared values but on technical limitations of the test design instead. In the workshop, research was identified that should result in a scientific basis for value judgments applied in decision making.
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Regulación Gubernamental , Plaguicidas/efectos adversos , Investigación/legislación & jurisprudencia , Animales , Congresos como Asunto , Productos Agrícolas , Contaminantes Ambientales/análisis , Contaminantes Ambientales/toxicidad , Unión Europea , Cooperación Internacional , Plaguicidas/análisis , Plaguicidas/toxicidad , Investigación/normas , Gestión de Riesgos/legislación & jurisprudencia , Gestión de Riesgos/métodos , Gestión de Riesgos/normasRESUMEN
Laparoscopic pericardiotomy, biopsy, and external drainage can be performed effectively in a safe and efficient manner for benign and malignant pericardial effusions. This technique, although minimally morbid, allows for pericardiotomy with biopsy and placement of large drains under visual control. In this article, we describe the surgical technique, including external drain placement. We discuss our experience with laparoscopic drainage of an infected benign effusion with tamponade in a patient with chronic renal failure. A diagnostic laparoscopic pericardiotomy in a patient with penetrating lower thoracic trauma is also described. Potential advantages and disadvantages of the laparoscopic approach are discussed.
Asunto(s)
Laparoscopía/métodos , Derrame Pericárdico/cirugía , Pericardiectomía/métodos , Adulto , Taponamiento Cardíaco/etiología , Drenaje , Humanos , Fallo Renal Crónico/complicaciones , Masculino , Persona de Mediana Edad , Derrame Pericárdico/complicaciones , Neumoperitoneo ArtificialRESUMEN
CONTEXT: Although the Turkish Medical Association has deemed "virginity examinations" a form of gender-based violence, women in Turkey are often subjected to such examinations by forensic physicians for both legal and social reasons. Little is known about these physicians' role and attitudes in this practice. OBJECTIVES: To assess forensic physicians' experiences and attitudes regarding virginity examinations in Turkey and suggest potential solutions to the problems identified. DESIGN: Cross-sectional self-administered survey. SETTING: Surveys were completed during the Forensic Science Congress held in Kusadasi in April 1998 as well as in urban academic and medical practice settings between April and October 1998. PARTICIPANTS: Of 158 physicians who practice, are formally trained in, or are in training for forensic medicine, 118 completed the survey (response rate, 74.7%). MAIN OUTCOME MEASURES: Frequency and circumstances of conducting virginity examinations, opinions regarding beneficial and adverse consequences of these examinations, and recommendations for changing the practice, as measured by a 100-item questionnaire. RESULTS: Overall, survey respondents reported conducting 5901 examinations in the previous 12 months; 4045 were conducted because of alleged sexual assault and 1856 for social reasons. Although 68% of forensic physicians indicated that they believed virginity examinations are inappropriate in the absence of an allegation of sexual assault, 45% had conducted examinations for social reasons. The majority of the respondents (93%) agreed that the examinations are psychologically traumatic for the patient. In addition, more than half (58%) reported that at least 50% of patients undergo examinations against their will. CONCLUSIONS: Nearly half of forensic physicians in Turkey conduct virginity examinations for social reasons despite beliefs that such examinations are inappropriate, traumatic to the patient, and often performed against the patient's will. Physicians' participation in such practices is inconsistent with principles of bioethics and international human rights.
Asunto(s)
Control de la Conducta , Medicina Legal , Derechos Humanos , Rol del Médico , Pautas de la Práctica en Medicina , Abstinencia Sexual , Actitud , Estudios Transversales , Femenino , Humanos , Jurisprudencia , Aplicación de la Ley , Menores , Medición de Riesgo , TurquíaRESUMEN
OBJECTIVES: This study assessed patterns of displacement and human rights abuses among Kosovar refugees in Macedonia and Albania. METHODS: Between April 19 and May 3, 1999, 1180 ethnic Albanian refugees living in 31 refugee camps and collective centers in Macedonia and Albania were interviewed. RESULTS: The majority (68%) of participants reported that their families were directly expelled from their homes by Serb forces. Overall, 50% of participants saw Serb police or soldiers burning the houses of others, 16% saw Serb police or soldiers burn their own home, and 14% witnessed Serb police or soldiers killing someone. Large percentages of participants saw destroyed mosques, schools, or medical facilities. Thirty-one percent of respondents reported human rights abuses committed against their household members, including beatings, killings, torture, forced separation and disappearances, gunshot wounds, and sexual assault. CONCLUSIONS: The present findings confirm that Serb forces engaged in a systematic and brutal campaign to forcibly expel the ethnic Albanian population of Kosovo. In the course of these mass deportations, Serb forces committed widespread abuses of human rights against ethnic Albanians.