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1.
J Heart Lung Transplant ; 20(3): 288-96, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11257554

RESUMEN

BACKGROUND: It is well documented that malnourished and/or obese surgical patients have increased morbidity and mortality post-operatively. Only a few studies investigating the effect of nutritional status on mortality are available pertaining to the transplant population. Since limited data are available on the nutritional status and its effects on mortality in the lung transplant population, we sought to ascertain whether there is an association between mortality and preoperative nutritional status. METHODS: We examined mortality during the first 3 months after transplantation. Patients were grouped by body mass index (BMI) categories as < 17 kg/m(2), 17 to < 20 kg/m(2), 20 to 25 kg/m(2) (reference group), > 25 to 27 kg/m(2), and > 27 kg/m(2). Additional risk factors retrieved from the pre-transplant records included age, gender, diagnosis, energy requirements, protein requirements, protein and caloric intake, and weight history. Logistic regression for univariate and multivariate analysis for mortality used recipient age, gender, disease category, pre-transplant cytomegalovirus (CMV) serology, transplant type (single or bilateral), and donor age, gender, and CMV serology. RESULTS: The likelihood estimates or odds ratios (ORs) of the risk of death within 90 days of lung transplantation for the BMI categories compared to the reference group were 3.7 for BMI < 17 kg/m(2) (p = 0.085), 1.6 for BMI < 17 to 20 kg/m(2) (p = 0.455), 3.5 for BMI > 25 to 27 kg/m(2) (p = 0.069), and 5.0 for BMI > 27 kg/m(2) (p = 0.003). CONCLUSIONS: In patients with a pre-transplant BMI < 17 kg/m(2) or > 25 kg/m(2) the risk of dying within 90 days post-transplant was increased. In patients with a pre-transplant BMI of > 27 kg/m(2) the risk was significantly higher in than the reference group.


Asunto(s)
Índice de Masa Corporal , Trasplante de Pulmón/mortalidad , Estado Nutricional , Adulto , Causas de Muerte , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Factores de Riesgo
3.
Am J Physiol Lung Cell Mol Physiol ; 279(6): L1075-82, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11076797

RESUMEN

We have recently demonstrated that primary cultured rat pneumocytes produce macrophage inflammatory protein-2 (MIP-2) in response to lipopolysaccharide (LPS) stimulation. In this study, we found that brefeldin A, by blocking anterograde transport from the endoplasmic reticulum (ER) to the Golgi apparatus, decreased LPS-induced MIP-2 in the culture medium and increased its storage in cells. This suggests that MIP-2 is secreted via a pathway from the ER to the Golgi apparatus, a process commonly regulated by microtubules. We further found that LPS induced depolymerization of microtubules as early as 1 min after LPS stimulation, and it lasted at least for 4 h. Preventing depolymerization of microtubules with paclitaxel (Taxol; 10 nM to 10 microM) partially inhibited LPS-induced MIP-2 production, whereas the microtubule-depolymerizing agents colchicine (1-10 microM) and nocodazole (1-100 microM) increased LPS-induced MIP-2 protein production without affecting MIP-2 mRNA expression. These results suggest that in pneumocytes, LPS-induced microtubule depolymerization is involved in LPS-induced MIP-2 production and that secretion of MIP-2 from pneumocytes is via the ER-Golgi pathway.


Asunto(s)
Quimiocinas/genética , Quimiocinas/metabolismo , Lipopolisacáridos/farmacología , Microtúbulos/inmunología , Mucosa Respiratoria/inmunología , Mucosa Respiratoria/metabolismo , Animales , Antineoplásicos/farmacología , Antineoplásicos Fitogénicos/farmacología , Brefeldino A/farmacología , Bronquios/citología , Bronquios/inmunología , Bronquios/metabolismo , Células Cultivadas , Quimiocina CXCL2 , Colchicina/farmacología , Retículo Endoplásmico/metabolismo , Expresión Génica/efectos de los fármacos , Expresión Génica/inmunología , Aparato de Golgi/metabolismo , Masculino , Microtúbulos/efectos de los fármacos , Nocodazol/farmacología , Paclitaxel/farmacología , Inhibidores de la Síntesis de la Proteína/farmacología , Alveolos Pulmonares/citología , Alveolos Pulmonares/inmunología , Alveolos Pulmonares/metabolismo , ARN Mensajero/análisis , Ratas , Ratas Sprague-Dawley , Mucosa Respiratoria/citología
4.
J Heart Lung Transplant ; 19(10): 984-94, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11044694

RESUMEN

BACKGROUND: Gene therapy provides the potential to modify donor organs to better withstand transplantation, but this has yet to be realized. In vivo gene transfer using adenoviral vectors has had limited success because of host immune response that induces inflammation and limits the amount and duration of transgene expression. We hypothesize that transplantation immunosuppression can attenuate the post-transfection host-immune response to allow for improved gene transfer following adenoviral-mediated transfection. METHODS: We intratracheally transfected with adenovirus containing the beta-galactosidase gene and randomized the rats to either the immunosuppression group, receiving daily cyclosporine, azathioprine, and methylprednisolone, or the control group, receiving no immunosuppression. We evaluated transgene expression and post-transfection inflammation at time points ranging from 1 day to 5 weeks. RESULTS: Following transfection, control rats showed relatively low levels of transgene expression, which rapidly decreased to non-detectable levels. In contrast, immunosuppressed rats demonstrated significantly higher levels of transgene expression overall (p < 0.00005), peaking at almost 3 times that of the control group (p < 0.02), and showing prolonged and elevated transgene expression at 5 weeks (p < 0.02). On histologic sections of the lungs, immunosuppressed rats exhibited overall lesser grades of post-transfection inflammation. CONCLUSIONS: Transplant immunosuppression provides the means to attenuate the severe immune response to adenoviral-mediated gene transfection and thereby increase and prolong transgene expression.


Asunto(s)
Adenoviridae/genética , Expresión Génica , Técnicas de Transferencia de Gen , Inmunosupresores/uso terapéutico , Pulmón/inmunología , Transfección , Transgenes , Animales , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Inmunohistoquímica , Mediciones Luminiscentes , Pulmón/patología , Masculino , Distribución Aleatoria , Ratas , Ratas Endogámicas Lew , Factores de Tiempo , Inmunología del Trasplante
5.
Cytokine ; 12(6): 644-54, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10843740

RESUMEN

Tumour necrosis factor alpha(TNF-alpha) is one of the most important pro-inflammatory cytokines, which plays an important role in host defense and acute inflammation related to tissue injury. The major source of TNF-alpha has been shown to be immune cells such as macrophages and neutrophils. In the present study, we demonstrated that LPS-treatment on alveolar epithelial cells isolated from adult rat lungs also induced a dose- and time-dependent release of TNF-alpha. The purity and identity of these cells were examined by immunofluorescent staining and confocal microscopy with antibodies for cytokeratin and pro-surfactant protein C, markers for epithelial cells and type II pneumocytes respectively. Positive staining of TNF-alpha was observed throughout the cell layer and localized intracellularly. LPS-induced TNF-alpha production from alveolar epithelial cells was blocked not only by cycloheximide, an inhibitor of protein translation, but also by actinomycin D, an inhibitor of gene transcription. The mRNA of TNF-alpha rapidly increased within 1 h of LPS stimulation. These data suggest that LPS-induced TNF-alpha production from alveolar epithelial cells is primarily regulated at the transcriptional level, which is different from that of macrophages and neutrophils. TNF-alpha produced by alveolar epithelial cells may function as an alert signal in host defense to induce production of other inflammatory mediators.


Asunto(s)
Regulación de la Expresión Génica/fisiología , Alveolos Pulmonares/fisiología , Mucosa Respiratoria/fisiología , Factor de Necrosis Tumoral alfa/genética , Animales , Células Cultivadas , Cicloheximida/farmacología , Dactinomicina/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Queratinas/análisis , Lipopolisacáridos/farmacología , Masculino , Biosíntesis de Proteínas/efectos de los fármacos , Alveolos Pulmonares/citología , Ratas , Ratas Sprague-Dawley , Mucosa Respiratoria/citología , Mucosa Respiratoria/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Genética/efectos de los fármacos , Factor de Necrosis Tumoral alfa/biosíntesis
6.
Am J Respir Cell Mol Biol ; 21(4): 510-20, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10502561

RESUMEN

Our recent studies have demonstrated that in response to lipopolysaccharide (LPS) challenge, alveolar epithelial cells produced tumor necrosis factor (TNF)-alpha, an early response cytokine in the inflammatory process. To investigate whether LPS-induced TNF-alpha release is related to other inflammatory mediators from the same cell type, we examined effects of LPS stimulation on macrophage inflammatory protein (MIP)-2 production by alveolar epithelial cells, and then examined the relationship between TNF-alpha and MIP-2 production. LPS stimulation induced a dose- and time-dependent release of MIP-2. The steady-state messenger RNA level of MIP-2 was significantly increased, with the MIP-2 protein localized within alveolar epithelial cells, as determined by confocal microscopy. The LPS-induced MIP-2 production is regulated at both the transcriptional and post-transcriptional levels. TNF-alpha also induced MIP-2 production from alveolar epithelial cells. Preincubation with an antisense oligonucleotide against TNF-alpha inhibited LPS-induced TNF-alpha in a dose-dependent and sequence-specific manner. The same antisense also inhibited MIP-2 production. The inhibitory effects were highly correlated. Polyclonal and monoclonal antibodies against TNF-alpha also attenuated LPS-induced MIP-2. These results suggest that LPS-induced MIP-2 release from alveolar epithelial cells may be mediated in part by TNF-alpha from the same cell type. This autoregulatory mechanism may amplify LPS-induced signals involved in host defense as well as in acute inflammatory reactions.


Asunto(s)
Lipopolisacáridos/farmacología , Monocinas/metabolismo , Alveolos Pulmonares/fisiología , Factor de Necrosis Tumoral alfa/fisiología , Animales , Secuencia de Bases , Quimiocina CXCL2 , Quimiocinas/biosíntesis , Cartilla de ADN/genética , Células Epiteliales/fisiología , Homeostasis , Técnicas In Vitro , Mediadores de Inflamación/fisiología , Monocinas/genética , Pruebas de Neutralización , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacología , Alveolos Pulmonares/citología , Procesamiento Postranscripcional del ARN/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Transcripción Genética/efectos de los fármacos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/genética
7.
Am J Physiol ; 277(3): L606-15, 1999 09.
Artículo en Inglés | MEDLINE | ID: mdl-10484469

RESUMEN

Lipopolysaccharide (LPS) polymerizes microfilaments and microtubules in macrophages and monocytes. Disrupting microfilaments or microtubules with cytochalasin D (CytoD) or colchicine can suppress LPS-induced tumor necrosis factor-alpha (TNF-alpha) gene expression and protein production from these cells. We have recently demonstrated that primary cultured rat alveolar epithelial cells can produce TNF-alpha on LPS stimulation. In the present study, we found that the LPS-induced increase in TNF-alpha mRNA level and protein production in alveolar epithelial cells was not inhibited by CytoD or colchicine (1 nM to 10 microM). In fact, LPS-induced TNF-alpha production was further enhanced by CytoD (1-10 microM) and inhibited by jasplakinolide, a polymerizing agent for microfilaments. Immunofluorescent staining and confocal microscopy showed that LPS (10 microg/ml) depolymerized microfilaments and microtubules within 15 min, which was prolonged until 24 h for microfilaments. These results suggest that the effects of LPS on the cytoskeleton and the role of the cytoskeleton in mediating TNF-alpha production in alveolar epithelial cells are opposite to those in immune cells. This disparity may reflect the different roles between nonimmune and immune cells in host defense.


Asunto(s)
Citoesqueleto/metabolismo , Depsipéptidos , Lipopolisacáridos/farmacología , Polímeros/metabolismo , Alveolos Pulmonares/metabolismo , Factor de Necrosis Tumoral alfa/biosíntesis , Citoesqueleto de Actina/efectos de los fármacos , Citoesqueleto de Actina/metabolismo , Animales , Células Cultivadas , Colchicina/farmacología , Citocalasina D/farmacología , Citoesqueleto/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Masculino , Microtúbulos/efectos de los fármacos , Péptidos Cíclicos/farmacología , Alveolos Pulmonares/citología , Alveolos Pulmonares/efectos de los fármacos , ARN Mensajero/antagonistas & inhibidores , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/genética , Factor de Necrosis Tumoral alfa/metabolismo
9.
J Thorac Cardiovasc Surg ; 116(6): 932-42, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9832683

RESUMEN

OBJECTIVE: Rapid reperfusion may be injurious to the ischemic lung. Our aim was to confirm that slow reperfusion improves postischemic pulmonary function and to elucidate the ultrastructural changes associated with slow versus rapid reperfusion. METHODS. We used an ex vivo perfused rat lung transplant model to study the effect of slow versus rapid reperfusion on subsequent lung function and morphologic conditional. Functional assessment was performed in (1) fresh lung, slowly reperfused; (2) fresh lung, rapidly reperfused; (3) ischemic lung (4 hours at 22 degrees C), slowly reperfused; and (4) ischemic lung, rapidly reperfused. RESULTS: In group 4, the shunt fraction (P=.001), airway pressure (P=.001), and wet/dry ratio (P=.01) were significantly higher than in groups 1 through 3. Light and electron microscopy of slowly reperfused ischemic lungs (n=4) appeared normal. Rapidly reperfused ischemic lungs (n=4) demonstrated massive alveolar edema hemorrhage, and epithelial "blebbing" by light microscopy. Electron microscopy identified the blebbing as separation of the epithelial layer from an intact basement membrane by edema fluid. The epithelial layer was disrupted in numerous locations. Complete disruption of all layers of the blood-gas barrier was occasionally present. CONCLUSION: Rapid reperfusion of the ischemic lung is an important contributing factor to reperfusion lung injury resulting in mechanical stress failure of the alveolar/capillary barrier. Gradual reintroduction of blood flow to the ischemic lung improves oxygenation.


Asunto(s)
Pulmón/ultraestructura , Daño por Reperfusión/patología , Reperfusión/efectos adversos , Insuficiencia Respiratoria/etiología , Estrés Fisiológico/complicaciones , Animales , Modelos Animales de Enfermedad , Pulmón/irrigación sanguínea , Pulmón/fisiopatología , Trasplante de Pulmón/patología , Masculino , Microscopía Electrónica , Distribución Aleatoria , Ratas , Ratas Wistar , Daño por Reperfusión/complicaciones , Daño por Reperfusión/fisiopatología , Pruebas de Función Respiratoria , Insuficiencia Respiratoria/patología , Insuficiencia Respiratoria/fisiopatología , Estrés Fisiológico/patología , Estrés Fisiológico/fisiopatología
10.
Transplantation ; 66(6): 723-32, 1998 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-9771835

RESUMEN

BACKGROUND: Lung dysfunction after transplantation continues to be a significant clinical problem. Soluble complement receptor 1 (sCR1) is a potent inhibitor of complement activation. We evaluated the inhibitory effect of sCR1 on complement activation and reperfusion injury in pig lung allografts. METHODS: In a randomized and blinded study, left lung transplantation was performed in 13 pigs. Donor lungs were flushed and then stored for 30 hr at 4 degrees C. Control pigs (n=7) received saline, and the treatment group (n=6) received 15 mg/kg sCR1 1 hr before reperfusion. One hour after reperfusion, the right pulmonary artery was clamped for 10 min to assess the function of the transplanted lung. Pulmonary function was assessed again on day 3. RESULTS: Complement inhibition was 93% in the sCR1 group and returned to baseline (8% inhibition) after 3 days. There was a trend toward a higher partial pressure of oxygen at 1 hr in the sCR1 group compared with the control group (mean +/- SE: 408+/-42 mmHg vs. 288+/-69 mmHg, P = 0.19). Alveolar ventilation was better in the sCR1 group than in the control group (P = 0.01) at 1 hr. Mixed venous saturation was significantly lower in the control group at both 1 hr (P = 0.02) and 3 days (P = 0.001). The wet/dry weight of the lung tissue was lower in the sCR1 group compared with the control group on day 3 (P < 0.05). Chemiluminescence, an index of phagocyte priming, was lower in the sCR1 group when cells were stimulated with complement opsonized zymosan but not when stimulated with zymosan or phorbol myristate acetate. CONCLUSION: sCR1 improves ventilation, reduces pulmonary edema, and may be beneficial in improving posttransplant lung oxygenation.


Asunto(s)
Proteínas Inactivadoras de Complemento/farmacología , Trasplante de Pulmón , Pulmón/efectos de los fármacos , Pulmón/fisiología , Receptores de Complemento/fisiología , Animales , Células CHO , Complemento C3b/análisis , Cricetinae , Técnica del Anticuerpo Fluorescente , Pulmón/citología , Oxígeno/sangre , Oxígeno/metabolismo , Presión Parcial , Distribución Aleatoria , Receptores de Complemento/sangre , Porcinos
11.
Ann Thorac Surg ; 63(5): 1468-70, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9146349

RESUMEN

We report our experience with 2 cases of simultaneous single-lung transplantation and lung volume reduction for emphysema. The lung volume reduction was undertaken electively in an attempt to improve overall lung function above that to be expected from single-lung transplantation alone. There were no postoperative problems related to the addition of lung volume reduction. The pulmonary function at 3 months was greater than that seen in a retrospective group of bilateral lung transplants previously reported from our institution.


Asunto(s)
Trasplante de Pulmón , Neumonectomía , Enfisema Pulmonar/cirugía , Deficiencia de alfa 1-Antitripsina , Femenino , Volumen Espiratorio Forzado , Humanos , Trasplante de Pulmón/fisiología , Masculino , Persona de Mediana Edad , Enfisema Pulmonar/fisiopatología
12.
Ann Thorac Surg ; 63(3): 800-5, 1997 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9066405

RESUMEN

BACKGROUND: Pulmonary arteriography has been reported to be useful in the preoperative assessment of patients with lung cancer to determine the technical resectability and feasibility of pneumonectomy by imaging the main right and left pulmonary arteries. In this report, we describe the use of selective pulmonary arteriography in the assessment of lobar resectability. METHODS: Selective pulmonary arteriography provides a detailed anatomic view of the lobar branches and has been used at our institution for the past 30 years to preoperatively investigate patients who are candidates for a sleeve lobectomy. RESULTS: Three cases are described that demonstrate the usefulness of selective pulmonary arteriography in the assessment of the technical feasibility of sleeve resection in patients with lung cancer. CONCLUSIONS: Arteriographic findings may accurately show whether a sleeve lobectomy is technically possible, that only a pneumonectomy is possible, or that the only safe way to ensure clearance of the pulmonary artery is to perform arterioplasty. This information may obviate an unnecessary thoracotomy in patients who are judged on the basis of a physiologic assessment to be unable to tolerate a pneumonectomy.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Neumonectomía/métodos , Arteria Pulmonar/diagnóstico por imagen , Anciano , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/cirugía , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía
13.
J Thorac Cardiovasc Surg ; 112(6): 1522-31; discussion 1531-2, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8975844

RESUMEN

METHODS: We have reviewed our experience in 38 patients with adenoid cystic carcinoma of the upper airway seen between 1963 and 1995. The mean age was 44.8 years (15 to 80 years) with a male/female ratio of 1:1.1. Thirty-two of the 38 patients were treated by resection and reconstruction (primary anastomosis 28; Marlex mesh prosthesis 4). Twenty-six of the 32 patients undergoing resection received adjuvant radiotherapy. Six patients with unresectable tumors were treated primarily with radiotherapy only. RESULTS: Pathologic examination revealed local invasion beyond the wall of the trachea in all patients. In a majority, microscopic extension was found in submucosal and perineural lymphatics, well beyond the grossly visible or palpable limits of the tumor. Lymphatic metastases were relatively uncommon, occurring in only five of 32 (19%) patients undergoing resection. Metachronous hematogenous metastases occurred in 17 of 38 patients (44%). Thirteen of these 38 patients (33%) had pulmonary metastases. Sixteen of 32 resections were complete and potentially curative. There were two deaths within 30 days of operation. The mean survival in the 14 patients undergoing complete resection was 9.8 years (12 months to 29 years). Sixteen of 32 resections were incomplete (residual tumor at the airway margin on final pathologic examination), with one operative death occurring in this group. The mean survival in the 15 surviving patients was 7.5 years (4 months to 21 years). Six patients were treated with primary radiation only and had a mean survival of 6.2 years (2 months to 14.3 years). In the patients with pulmonary metastases, mean survival was 37 months (4 months to 7 years) from the time of diagnosis of the pulmonary metastasis until their death. CONCLUSION: Adenoid cystic carcinoma of the upper airway is a rare tumor, which is locally invasive and frequently amenable to resection. Although late local recurrence after resection is a feature of this tumor (up to 29 years), excellent long-term palliation is commonly achieved after both complete and incomplete resection. There was a small difference in survival between patients having complete and incomplete resection. Long periods of control can be obtained with radiotherapy alone. The best results, in this series of patients, were obtained by resection. Adjuvant radiotherapy is assumed to favorably influence survival.


Asunto(s)
Carcinoma Adenoide Quístico/radioterapia , Carcinoma Adenoide Quístico/cirugía , Neoplasias Nasofaríngeas/radioterapia , Neoplasias Nasofaríngeas/cirugía , Análisis Actuarial , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma Adenoide Quístico/mortalidad , Carcinoma Adenoide Quístico/secundario , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Nasofaríngeas/mortalidad , Neoplasias Nasofaríngeas/patología , Polietilenos , Polipropilenos , Radioterapia Adyuvante , Estudios Retrospectivos , Mallas Quirúrgicas , Análisis de Supervivencia , Resultado del Tratamiento
14.
J Appl Physiol (1985) ; 80(5): 1835-40, 1996 May.
Artículo en Inglés | MEDLINE | ID: mdl-8727574

RESUMEN

Isolated perfused lung systems are commonly used to assess lung function in experimental studies. Assessment of hemodynamics and gas-exchange function in these systems is limited by the availability of venous blood. This study describes and validates a rat lung perfusion circuit in which a double-lung block ventilated with a hypoxic gas mixture [inspired O2 fraction (FIO2) 0.04; inspired CO2 fraction 0.08; deoxygenator (Deoxy) block] is used to provide blood with blood gases that are similar to mixed venous values to perfuse a study lung (FIO2 0.21; left lung only). This allows extended assessment of hemodynamics and gas exchange. Fifty adult male Wistar rats (300-400 g) were used as double-lung donors. Twenty-five perfusions (of both Deoxy and study lungs) were performed in four protocols (groups 1-5; n = 5). In protocol 1 (group 1), we tested whether exposure to room air affects the gas composition of the blood in the system. We found that the gas composition of the venous reservoir blood was identical to that of the blood entering the study block. In protocol 2, the effect of perfusion time and perfusion flow rate on the stability of the system was assessed. Lungs were perfused at 4 and 12 ml/min (groups 2 and 3, respectively), and the procedure was discontinued if edema or a marked decline in hemodynamics or gas-exchange function was observed. Pulmonary function was excellent and remained stable for 3 (at 12 ml/min) and 5 h (at 4 ml/min). In protocol 3, we examined whether hypoxic ventilation in the Deoxy lungs affects the stability of the system. Despite the low FIO2 used in the Deoxy lungs, the mean pulmonary arterial pressure-to-blood flow relationships in the study and Deoxy lungs were similar. Finally, in protocol 4, perfusion of a damaged study lung did not impair the function of the system. We conclude that this model permits reliable assessment of pulmonary function in rats under controlled ventilation and perfusion conditions. The use of a Deoxy double-lung block simplifies the perfusion apparatus and eliminates the main cause of instability of other systems that use an anesthetized host animal to provide venous blood.


Asunto(s)
Hipoxia/fisiopatología , Pulmón/fisiología , Modelos Biológicos , Animales , Análisis de los Gases de la Sangre , Masculino , Perfusión , Ratas , Ratas Wistar
15.
J Heart Lung Transplant ; 15(3): 260-8, 1996 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8777209

RESUMEN

BACKGROUND: A shortage of suitable brain-dead donors continues to severely limit lung transplantation. Use of donors with nonbeating hearts has been suggested as a solution. Lungs are unique, in that aerobic metabolism can continue in the absence of blood circulation because oxygen is present in airways and alveoli. Animal studies have shown reasonable cadaveric graft function up to several hours after sudden death by drug administration. However, hemodynamic instability before death may worsen lung function through activation and pulmonary sequestration of neutrophils and release of inflammatory mediators. Because many potential cadaveric donors experience hypotension before death, this study was undertaken to assess the effect of hypotensive shock on cadaveric lung viability. METHODS: A rat isolated lung reperfusion model was used to assess pulmonary function over 3 hours of reperfusion or until gross pulmonary edema developed. Twenty-five rats were randomly allocated to the following study groups, which were based on status before lung harvest: (1) control: no interventions; (2) hypotensive: 1 hour of hypotension by exsanguination to a mean blood pressure of 30 to 40 mm Hg; (3) cadaver: death by cervical dislocation followed by 3 hours of in situ lung ischemia; (4) hypotensive + 3 hours cadaver: 1 hour of hemorrhagic shock, followed by death and 3 hours of in situ ischemia; (5) hypotensive + 2 hours cadaver: similar to group 4, except the in situ ischemia was abbreviated to 2 hours. RESULTS: No significant differences were found among group 1, 2, or 3 lungs with regard to wet to dry weight ratios, gas exchange, and pulmonary arterial or airway pressures. However, all group 4 lungs became grossly hemorrhagic and developed severe pulmonary edema within 10 minutes of reperfusion. Group 5 lungs fared only marginally better, with two of five lungs tolerating 3 hours of reperfusion. CONCLUSIONS: A period of hypotension before death severely impairs cadaveric lung viability.


Asunto(s)
Muerte Encefálica/fisiopatología , Hipotensión/fisiopatología , Trasplante de Pulmón/fisiología , Intercambio Gaseoso Pulmonar/fisiología , Donantes de Tejidos , Supervivencia Tisular/fisiología , Obtención de Tejidos y Órganos , Animales , Humanos , Masculino , Peroxidasa/metabolismo , Edema Pulmonar/fisiopatología , Presión Esfenoidal Pulmonar/fisiología , Ratas , Ratas Wistar , Choque/fisiopatología
16.
Can J Surg ; 36(4): 321-5, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8396496

RESUMEN

Intra- and extrahepatic bile-duct strictures, papillary stenosis and acalculous cholecystitis have all been described in ill patients with acquired immunodeficiency syndrome (AIDS). Acalculous cholecystitis associated with cytomegalovirus (CMV), Cryptosporidium or Campylobacter organisms has typically been described in critically ill or moribund patients. The authors report a case of acute acalculous CMV cholecystitis in a 28-year-old man who presented with abdominal pain. The patient was infected with the human immunodeficiency virus (HIV) but was ambulatory and had had no AIDS-defining illness. The patient did not have any well-recognized risk factors for acalculous cholecystitis, showing that this entity can occur in relatively healthy HIV-infected patients as well as in the terminal stages of AIDS. The diagnosis should be considered when such a patient presents with abdominal pain. Furthermore, this patient had sclerosing cholangitis of the intra- and extrahepatic bile ducts as well as papillary stenosis. The cause of the acalculous cholecystitis was presumed to be CMV, but the disease progressed despite therapy with foscarnet.


Asunto(s)
Infecciones Oportunistas Relacionadas con el SIDA/diagnóstico , Dolor Abdominal/etiología , Ampolla Hepatopancreática , Colangitis Esclerosante/diagnóstico , Colecistitis/diagnóstico , Infecciones por Citomegalovirus/diagnóstico , Infecciones Oportunistas Relacionadas con el SIDA/complicaciones , Infecciones Oportunistas Relacionadas con el SIDA/patología , Infecciones Oportunistas Relacionadas con el SIDA/terapia , Enfermedad Aguda , Adulto , Biopsia , Colangiopancreatografia Retrógrada Endoscópica , Colangitis Esclerosante/complicaciones , Colecistectomía , Colecistitis/complicaciones , Colecistitis/patología , Colecistitis/terapia , Terapia Combinada , Enfermedades del Conducto Colédoco/complicaciones , Enfermedades del Conducto Colédoco/diagnóstico , Enfermedades del Conducto Colédoco/cirugía , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/patología , Infecciones por Citomegalovirus/terapia , Sondas de ADN , Diagnóstico Diferencial , Foscarnet/uso terapéutico , Humanos , Hígado/patología , Pruebas de Función Hepática , Masculino
17.
J Thorac Cardiovasc Surg ; 103(2): 314-25, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1370970

RESUMEN

We have previously demonstrated that a low-potassium dextran solution provides superior and more reliable preservation of lungs for 12 hours than that provided by the commonly used Euro-Collins solution. This study was designed to examine the individual contributions of dextran 40 and a low (extracellular) potassium concentration to lung preservation. In a randomized, blinded study using an in vivo canine single-lung transplant model, lungs preserved with low-potassium dextran solution (K+, 4 mmol/L; dextran 40, 20 gm/L) were compared to lungs preserved with low-potassium, no-dextran solution (K+, 4 mmol/L) and high-potassium dextran solution (K+, 123 mmol/L; dextran 40, 20 gm/L). The lungs were assessed immediately and 3 days after transplantation. The low-potassium dextran solution provided excellent immediate pulmonary function with little variability (arterial oxygen tension, 519 +/- 12 mm Hg, measured on the transplanted lung alone, inspired oxygen fraction = 1.0, n = 6). Removing the dextran 40 from the flush solution (low-potassium group) led to a significant deterioration in pulmonary function (arterial oxygen tension, 243 +/- 78 mm Hg, n = 6, p less than 0.01). The high-potassium dextran solution provided extremely poor preservation (arterial oxygen tension, 176 +/- 79 mm Hg; n = 6; p less than 0.01). Two animals in this group died within 6 hours of operation. Viability of the transplanted bronchus was significantly improved with the two solutions containing dextran 40. These results indicate that dextran 40 and low potassium concentration both contribute significantly to the uniformly excellent 12-hour lung preservation seen with the low-potassium dextran solution.


Asunto(s)
Dextranos , Perros , Trasplante de Pulmón , Preservación de Órganos , Potasio , Animales , Bronquios/patología , Bronquios/trasplante , Hemodinámica , Pulmón/patología , Circulación Pulmonar , Soluciones
18.
J Thorac Cardiovasc Surg ; 103(2): 326-8, 1992 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-1370971

RESUMEN

Improved lung preservation with a low-potassium dextran-containing solution has been previously demonstrated. In a subsequent study, it was shown that dextran 40 contributes significantly to this improved preservation. In the current in vitro study, human neutrophils suspended in lung preservation solutions (low potassium with dextran and low potassium without dextran) were stimulated to produce superoxide radicals. The presence of dextran in the solution did not significantly alter the amount of superoxide measured in the assay (low potassium with dextran, 4.149 +/- 0.144 nmol/10(6) cells/20 min; low potassium without dextran, 3.896 +/- 0.215; p greater than 0.2). This suggests that dextran 40 did not appreciably scavenge superoxide radicals, nor did it alter the production of superoxide radicals by stimulated neutrophils. Thus the significantly improved lung preservation seen with the use of dextran 40 is probably not mediated by a superoxide radical scavenging process.


Asunto(s)
Dextranos , Depuradores de Radicales Libres , Trasplante de Pulmón , Preservación de Órganos , Superóxidos/metabolismo , Humanos , Neutrófilos/metabolismo , Potasio , Soluciones , Superóxido Dismutasa/farmacología , Acetato de Tetradecanoilforbol/farmacología
19.
Transplantation ; 52(4): 621-6, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1718065

RESUMEN

Limited availability of donor organs is a major factor restricting the clinical application of lung transplantation. Improvements in preservation techniques are essential for prolonging storage time and improving lung function following transplantation. The present investigation used primary cultures of adult rat alveolar type II cells as a model for evaluating lung-preservation solutions. Type II cells were plated onto tissue-culture plastic at a density 5 x 10(5) cells/cm2 and maintained in Dulbecco's modified Eagle's medium containing 10% fetal bovine serum (D10) for 40 hr. Cells were then exposed to Euro-Collins solution or a low-potassium-dextran solution (LPD). At designated time points, measurements of lactate-dehydrogenase (LDH) release, protein content, and incorporation of 3H-thymidine into cellular DNA were made. During 12 hr of "storage" at 37 degrees C, cells maintained in LPD released less LDH (14.3 +/- 1.2% of cellular total, mean +/- SEM, n = 5) than their counterparts stored in EC (20.6 +/- 1.6%, P less than 0.05). During the 36 hr following a 6-hr exposure to preservative solutions, LPD-treated cells incorporated more thymidine per mg of protein (2566 +/- 419.8 cpm/micrograms protein, mean +/- SEM, n = 6) compared with cells maintained continuously in D10 (1431 +/- 351, P less than 0.05). By contrast, cells exposed to EC incorporated less thymidine (82.2 +/- 62.8 cpm/micrograms protein) than either cells maintained in LPD or D10 (P less than 0.01 for each comparison). These results suggest that LPD solution is less cytotoxic than EC and that LPD enables higher levels of metabolic activity in recovering epithelial cells. In vitro cultures of type II epithelial cells are a useful model system for the study of lung preservation and posttransplantation lung injury.


Asunto(s)
Dextranos , Soluciones Hipertónicas , Pulmón/citología , Preservación de Órganos/métodos , Potasio , Fosfatasa Alcalina , Animales , Células Cultivadas , Células Epiteliales , Epitelio/efectos de los fármacos , Concentración de Iones de Hidrógeno , L-Lactato Deshidrogenasa/metabolismo , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Masculino , Alveolos Pulmonares/citología , Alveolos Pulmonares/efectos de los fármacos , Alveolos Pulmonares/metabolismo , Ratas , Ratas Endogámicas , Soluciones
20.
Ann Thorac Surg ; 52(2): 258-64, 1991 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-1713756

RESUMEN

Despite omentopexy of the bronchial anastomosis, donor airway ischemia remains a problem after lung transplantation. This study examined the hypothesis that surface abrasion and topical application of basic fibroblast growth factor (bFGF) would enhance omental revascularization of trachea in a rabbit heterotopic autograft model. Tracheal segments were excised, primary tracheal anastomoses performed, and the segments placed in the peritoneal cavity wrapped in omentum. Animals were randomized to one of six groups according to tracheal segment treatment: control, surgical abrasion, Surgicel wrap with topical bFGF, Surgicel wrap with bFGF vehicle, Gelfoam wrap with bFGF, and topical bFGF alone. One week later, animals were heparinized, perfused with Aquablak dye, and killed. Tracheal segments were excised and sectioned for light microscopic quantitative assessment of viability and dye perfusion. There was no significant improvement in viability or perfusion between abraded tracheal segments or segments treated with bFGF/Gelfoam or bFGF alone when compared with control segments. Airways wrapped in Surgicel had significantly greater ischemic injury compared with the control group, regardless of bFGF application. Neither surgical abrasion nor topical bFGF increased omental revascularization of transplanted tracheal segments after 7 days.


Asunto(s)
Factor 2 de Crecimiento de Fibroblastos/farmacología , Neovascularización Patológica , Epiplón/irrigación sanguínea , Tráquea/irrigación sanguínea , Tráquea/trasplante , Obstrucción de las Vías Aéreas/etiología , Animales , Trasplante de Pulmón , Complicaciones Posoperatorias , Conejos
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