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Biomedical subjects

A Chapelier

Publications and source records attributed to A Chapelier.

At least 37 records · Page 2Linked to original sources
PubMed1998

[Surgical excision of pulmonary metastasis of cancer of the breast: apropos of 40 patients].

Between 1987 and 1995, 52 breast cancer patients had a surgical resection of lung secondaries. In 40 patients, the diagnosis of metastatic breast cancer could be confirmed following pathological examination. Five-year survival rates of these 40 patients was 54 +/- 8% and 5-year disease free survival was 30 +/- 8%. The median survival (70 months) of these patients was better than that of 57 patients with isolated lung metastases who had been treated conservatively (chemo- or/and hormonotherapy) during the same time interval. Twenty-six patients benefitted from a radical excision and had a longer disease free interval (42 versus 27 months, p = 0.03) than patients who had had a wedge resection. Overall survival was not significantly different (71 versus 41 months, p = 0.07). We feel that isolated lung nodules may best be treated by radical (segment or lobe) excision, in particular since preoperative differential diagnosis with primary lung cancer may be difficult. In the presence of multiple nodules, first line medical treatment by chemo- or hormonotherapy should be advocated, allowing to reduce the tumor load and to optimize survival in association with surgery.

Adult↗
PubMed1997

Tracheal growth after slide tracheoplasty.

OBJECTIVE: Our goal was to investigate the effects of slide tracheoplasty on tracheal growth in newborn piglets. METHODS: Slide tracheoplasty was performed on normal trachea (n = 6) and a model of tracheal stenosis resembling that seen in infants (n = 6). After division of the trachea at its midportion between the second cartilaginous ring above and the right upper lobe takeoff below (around 23 rings), the proximal and distal segments were incised vertically on opposite anterior and posterior surfaces and reconstructed together. RESULTS: The reconstructed tracheas lengthened and their cross-sectional areas enlarged linearly at a rate of 0.94 cm per month and 1.55 mm2/kg, respectively, as the piglets grew over a 6-month period from 4.7 +/- 0.6 to 64.4 +/- 5.7 kg (+/- standard deviation). Growth was not different between the two studied groups. There was no narrowing or late restenosis. The mean anastomotic cross-sectional area was overall 1.63 +/- 0.28 times larger (range 1.2 to 2.7) than the cross-sectional area of the unreconstructed trachea. When the animals were put to death, all tracheal lumina were completely lined with normal respiratory epithelium and all layers were histologically intact; anastomotic trachealis muscles contracted less (p < 0.001) but relaxed similarly to those muscles lining normal tracheas. Tracheal blood supply was macroscopically and microscopically normal in both groups; however, newborn piglets had an almost twofold increased number of intramural capillary vessels as opposed to adult pigs (p < 0.001). CONCLUSIONS: Results suggest that slide tracheoplasty is not limited by the length of stenosis, provides a permanent enlargement of the cross-sectional airway diameter, does not compromise tracheal vascular supply, and does not impair tracheal growth as somatic growth continues.

Animals↗
PubMed1997

Prevention of ischemia-reperfusion lung injury by sulfated Lewis(a) pentasaccharide. The Paris-Sud University Lung Transplantation Group.

Inhibition of polymorphonuclear neutrophil (PMN) adhesion to the pulmonary endothelium attenuates ischemia-reperfusion (I/R) lung injury. We hypothesized that 3'-sulfated Lewis(a) (SuLa), a potent ligand for the selectin adhesion molecules, may have a beneficial effect on I/R lung injury, as measured by the filtration coefficient (K(fc)), and reduce pulmonary sequestration of PMN as assessed by the lung myeloperoxidase (MPO) activity. Blood-perfused rat lungs were subjected to 30 min of perfusion, 60 min of warm ischemia, and 90 min of reperfusion after treatment with either SuLa (200 microg) or saline. Effects of SuLa on PMN adhesion to cultured human umbilical vein endothelial cells (HUVEC) stimulated with tumor necrosis factor-alpha and calcium ionophore were also investigated. Compared with preischemia conditions, I/R induced a significant increase in K(fc), which was attenuated with SuLa (80 +/- 8 vs. 30 +/- 5%; P < 0.001). SuLa reduced lung MPO and PMN adhesion to stimulated HUVEC. These results indicate that SuLa reduces I/R-induced lung injury and PMN accumulation in lung. This protective effect might be related to inhibition of PMN adhesion to endothelial cells.

Animals↗
PubMed1997

Effects of various timings and concentrations of inhaled nitric oxide in lung ischemia-reperfusion. The Paris-Sud University Lung Transplantation Group.

Experimental studies reveal that inhaled nitric oxide (NO) can prevent, worsen, or have no effect on lung injury in the setting of ischemia-reperfusion (I-R). We tested the hypothesis that these disparate effects could be related to differences in the timing of administration and/or concentration of inhaled NO during I-R. Isolated rat lungs were subjected to 1-h periods of ischemia followed by 1-h periods of blood reperfusion. We investigated the effects of NO (30 ppm) given during ischemia, NO (30 or 80 ppm) begun immediately at reperfusion, or NO (30 ppm) given 15 min after the beginning of reperfusion, on total pulmonary vascular resistance (PVR), the coefficient of filtration (Kfc), the lung wet/dry weight ratio (W/D) of lung tissue, and lung myeloperoxidase activity (MPO). A control group did not receive NO. NO given during ischemia had no effect on Kfc or MPO, but decreased PVR. NO (30 ppm) during reperfusion (early or delayed) decreased PVR, W/D, Kfc and MPO. NO at 80 ppm decreased PVR and MPO but not W/D or Kfc. In conclusion, NO at 30 ppm, given immediately or in a delayed fashion during reperfusion, attenuates I-R-induced lung injury. NO at 30 ppm given during ischemia or at 80 ppm during reperfusion is not protective.

Administration, Inhalation↗
PubMed1996

Gene therapy in lung transplantation: feasibility of ex vivo adenovirus-mediated gene transfer to the graft.

Lung transplantation is associated with complications such as reperfusion injury and graft rejection. Gene therapy targeted to the graft offers a promising approach to the prevention of these complications. Because adenovirus vectors can transfer genes in vivo to the lung vasculature, we evaluated the feasibility of adenovirus-mediated gene transfer to the lung graft in a porcine model of left lung allotransplantation. Following removal of the donor lung, an adenovirus vector encoding the beta-galactosidase (beta-Gal) gene was injected ex vivo into the lumen of the upper lobe pulmonary artery of the graft. After 2 hr of incubation at 10 degrees C, the lung graft was implanted into the recipient animal. Three days later, the animals were sacrificed and the lung graft was evaluated for beta-Gal activity. No beta-Gal activity was detected in the left lower lobe used as a control. In contrast, beta-Gal activity was detected in endothelial cells of the left upper lobe pulmonary circulation, and was also observed in airway and alveoli epithelial cells. However, less than 1% of cells of the graft expressed beta-Gal. In vitro experiments showed that this may be explained in part by the low temperature and the short duration of adenovirus incubation within the graft, and by the low susceptibility of porcine cells to human adenovirus. Furthermore, expression of the exogenous gene occurred in several organs of recipient animals. Thus, adenovirus-mediated gene transfer to the lung graft is feasible ex vivo, but several parameters limit gene transfer efficiency and need to be improved before clinical application is attempted.

Adenoviridae↗
PubMed1996

[Intrathoracic goiters. 62 surgically treated patients].

OBJECTIVES: Intrathoracic goitres present as tumors of the upper mediastinum. Malignancy is uncommon, but sudden or progressive development often leads to compression of the trachea. We report here our experience with surgical exeresis. METHODS: From 1980 to 1995, we operated 62 patients with intrathoracic goitre. There were 23 men and 39 women (mean age 63 years). The main manifestations leading to diagnosis were dyspnea (n = 20; 32%) and identification of a mediastinal formation on routine chest x-rays (n = 19; 30%). RESULTS: Antevascular goitre was seen in 24 patients (39%) and retrovascular goitre in 38 (61%). The retrovascular goitres were located anteriorly and laterally to the trachea in 21 patients (34%) and posteriorly in 17 (27%). Simple cervicotomy was used in 57 patients (92%). Manubriotomy (n = 1) and total sternotomy (n = 4) were also required. All intrathoracic goitres removed were benign. Post-operative mortality was nul and morbidity was 11%: 2 cases of hypocalcemia and 2 tracheomalacias including 1 with recurrent nerve palsy and one with hematoma and pulmonary infection. CONCLUSION: Surgical exeresis of intrathoracic goitre is essentially required in case of respiratory distress due to compression of the trachea. Morbidity is low with simple cervicotomy.

Adult↗
PubMed1996

Lasting beneficial effect of short-term inhaled nitric oxide on graft function after lung transplantation. Paris-Sud University Lung Transplantation Group.

The combination of ischemia and reperfusion after lung transplantation is characterized by endothelial damage, neutrophil sequestration, and decreased release of endothelial nitric oxide. Because nitric oxide has been shown to selectively dilate the pulmonary vasculature, abrogate neutrophil adherence, and restore endothelial dysfunction, we hypothesized that inhaled nitric oxide given for 4 hours during initial reperfusion might attenuate reperfusion injury in a porcine model of left single-lung transplantation. We tested hemodynamic and gas exchange data, lung neutrophil sequestration, and pulmonary artery endothelial dysfunction after 4 and 24 hours of reperfusion in 12 pigs randomly assigned to nitric oxide and control groups. Harvested lungs were preserved in normal saline solution for 24 hours at 4 degrees C. During transplantation, inflatable cuffs were placed around each pulmonary artery to allow separate evaluation of each lung by occluding flow. Compared with the transplanted lungs in the control group, transplanted lungs in pigs treated with inhaled nitric oxide significantly improved gas exchange, pulmonary vascular resistance, shunt fraction, and oxygen delivery at 4 and 24 hours after reperfusion. Neutrophil sequestration, as measured by the neutrophil-specific enzyme myeloperoxidase and the alveolar leukocyte count per light microscopic field, was significantly lower at 24 hours after reperfusion in the transplanted lungs of the nitric oxide group. The nitric oxide-treated native right lungs exhibited significantly reduced increase in neutrophil accumulation compared with that in control native right lungs. After 24 hours of reperfusion, endothelium-dependent relaxation to acetylcholine was similarly and severely altered in both groups. We conclude that short-term inhaled nitric oxide given during the first 4 hours of reperfusion after lung transplantation significantly attenuates reperfusion injury, improving graft function as long as 24 hours after operation. This effect is probably mediated by a decrease in neutrophil sequestration. A protective effect on the contralateral lung was also observed. Inhaled nitric oxide may be a suitable agent when an acute reperfusion phenomenon is anticipated.

Administration, Inhalation↗
PubMed1996

Prevention of ischemia-reperfusion lung injury by inhaled nitric oxide in neonatal piglets.

Lung ischemia-reperfusion results in a decrease in the release of nitric oxide (NO) by the pulmonary endothelium. NO may have lung-protective effects by decreasing neutrophil accumulation in the lung. We tested whether NO inhalation would attenuate reperfusion-induced endothelial dysfunction and increases in microvascular permeability and total pulmonary vascular resistance (RT) by preventing neutrophil lung accumulation. After baseline determinations of RT, coefficient of filtration (Kfc), and circulating neutrophil counts, isolated neonatal piglet lungs were subjected to a 1-h period of ischemia followed by a 1-h period of blood reperfusion and reventilation with or without addition of NO (10 ppm). NO prevented reperfusion-induced increases in RT and Kfc, as well as the decrease in circulating neutrophils. After reperfusion, increases in Kfc were correlated with decreases in circulating neutrophils. NO prevented reperfusion-induced decrease in endothelium-dependent relaxation in precontracted pulmonary arterial rings. This demonstrates that inhaled NO prevents microvascular injury, endothelial dysfunction, and pulmonary neutrophil accumulation in a neonatal piglet model of lung ischemia-reperfusion.

Animals↗
PubMed1996

Respiratory sensation related to resistive loads in lung transplant recipients.

In order to assess the contribution of pulmonary afferent nerves to the processing of respiratory sensation, we compared sensation related to inspiratory resistive loaded breathing in 14 lung transplant recipients with normal lung function with that in 14 matched healthy control subjects. Respiratory sensation was characterized for each subject by the correlation coefficient and slope of the linear relationship between the intensity of sensation (expressed as Borg scores [BSc]) and peak inspiratory mouth pressure (peak Pm), which was considered the main physical stimulus of the sensation. Individual correlation coefficients were very high and did not differ between lung transplant recipients and controls. In contrast, individual slopes of BSc as a function of peak Pm (BSc/peak Pm slopes) were significantly lower in lung transplant recipients than in controls (0.63 versus 1.26; p < 0.01). Furthermore, ventilatory responses to external loads differed significantly between lung transplant recipients and controls in terms of higher values and ranges of generated peak Pm and peak inspiratory flow in lung transplant recipients than in controls (all p < 0.05). These results suggest that pulmonary afferent nerves may contribute to ventilatory and sensory responses to external loads. However, as suggested by the inverse relation between BSc/peak Pm slopes and peak Pm ranges, higher stimulus ranges in lung transplant recipients may also have contributed to intergroup differences in respiratory sensation related to loaded breathing.

Adult↗
PubMed1995

Experimental tracheal and tracheoesophageal allotransplantation. Paris-Sud University Lung Transplantation Group.

We investigated the effects of allograft perfusion with a preservative technique and of combined thyrotracheoesophageal implantation on airway epithelium of long segments of thyrotracheal grafts allotransplanted on their own vascular pedicles into immunosuppressed pigs. Four groups of five animals each underwent heterotopic (into the neck) thyrotracheal (group 1) and thyrotracheoesophageal (group 2) and orthotopic thyrotracheal (group 3) and thyrotracheoesophageal (group 4) allotransplantation. Allograft revascularization included (1) interposition of donor right subclavian artery--incorporating the inferior thyroid artery--to recipient right carotid artery (end-to-end fashion) and (2) end-to-side anastomosis of donor anterior vena cava to recipient right external jugular vein. All thyrotracheoesophageal blocks were harvested after inferior thyroid artery perfusion with 4 degrees C Euro-Collins solution. The overall lengths of tracheal and esophageal grafts were 10.7 +/- 2.7 cm and 13.4 +/- 3.6 cm, respectively. In the heterotopic groups, all allografts were viable and histologically normal at postmortem examination and the incidence and severity of airway ischemia and rejections (at equal residual levels of cyclosporine) were not different between groups 1 and 2. In the orthotopic groups, the first two pigs died of airway collapse with histologically normal grafts. In the remaining pigs, temporary airway stenting was inserted and allografts remained viable and histologically intact for their entire length 30 days after transplantation. Transplanted tracheal smooth muscles had concentration-dependent contractions and relaxations similar to those of nontransplanted (native) tracheas. This study documents the feasibility of allotransplanting long tracheal and esophageal segments on their own vascular pedicles and demonstrates that allograft preservation and thyrotracheoesophageal transplantation are equally effective in minimizing airway ischemia. Thyrotracheoesophageal transplantation does not enhance recipient alloimmune response compared with thyrotracheal transplantation alone.

Animals↗
PubMed1995

Prognostic significance of peritumoural blood and lymphatic vessel invasion by tumour cells in T4 non-small cell lung cancer following induction therapy.

We investigated the impact of new biological prognostic factors is in 28 patients receiving a median of two courses of cisplatin-based chemotherapy with (n = 14) or without (n = 14) radiation and operation for stage IIIB (T4) non-small cell lung cancer (NSCLC). After induction therapy, 5 patients had a complete and 21 a partial response; 2 had a stable disease. A complete resection was made in 26 patients (93%). Five patients (18%) had their primary tumour and involved vestiges completely sterilized. In the remaining 23, the majority of the tumours showed abnormalities in the p53 gene expression (56%), harboured proliferating cells (91%) and induced angiogenesis (91%). Peritumoural blood and lymphatic vessel invasion (PBLVI) by tumour emboli was observed in 6 tumours. With a median follow-up of 25 months, overall 3-year survival was 48%; disease-free survival (DFS) has not been reached yet. The only significant factor influencing DFS in multivariate analysis was PBLVI by tumour cells; PBLVI-positive patients had a significantly higher likelihood ratio (P = 0.000001) of developing metastasis than their PBLVI-negative counterparts. This study documents the prognostic implication of PBLVI by tumour cells in T4 NSCLC.

Adult↗
PubMed1995

Technique of superior vena cava resection and reconstruction.

Superior vena cava (SVC) resection and reconstruction is a technically demanding procedure associated with several concerns. During operation, continuous arterial and venous pressure measurements are essential to monitor and maintain the physiologic arterial-venous brain parenchymal gradient. Technical details mitigating this hemodynamic compromise include intraluminal shunt procedures, pharmacologic agents and fluid implementation, short venous clamping time, and anticoagulation therapy. SVC replacement is usually afforded using a normal or ringed polytetrafluoroethylene graft.

Anastomosis, Surgical↗
PubMed1995

Operative technique of bullectomy.

The exact indications and long-term results of surgical bullectomy are still not completely clear. Patients with large-sized, compressive bullae with a normal or near-normal underlying lung parenchyma may benefit from surgical bullectomy (when carefully performed) because it relieves symptoms of dyspnea and improves exercise tolerance. By contrast, the value of surgical bullectomy in patients with diffuse, noncompressive bullous disease is less satisfactory and clear, although bilateral pneumectomy (volume reduction) has been proposed recently as an alternative to lung transplantation.

Humans↗
PubMed1995

Pentoxifylline and lung ischemia-reperfusion injury: application to lung transplantation. Université Paris-Sud Lung Transplant Group.

Pentoxifylline (PTX) attenuates neutrophil-mediated lung injury in several models of acute lung inflammation. Because pulmonary neutrophil sequestration is the main determinant of ischemia-reperfusion (IR) injury in lung transplantation, we sought to determine whether or not PTX prevented IR injury in isolated perfused rat and rabbit lungs submitted to IR, and in pigs after left lung allotransplantation. In rat lungs after IR, the coefficient of lung endothelial permeability (Kfc) increased by 112 +/- 12% in controls and by 27 +/- 8% (p < 0.001) in PTX-treated lungs. After IR, lung myeloperoxidase and blood neutrophil count decrease were lower with PTX than in controls, and the changes in Kfc were correlated with the percentage decrease in blood neutrophils during reperfusion. In rabbit lungs, endothelium-dependent relaxation in isolated pulmonary arterial rings was decreased in the control group and normal in the PTX group. In pigs ventilated with pure oxygen, the PaO2 was greater in the PTX group than in the control group (423 +/- 49 vs. 265 +/- 43 mm Hg; p < 0.05), whereas the total pulmonary vascular resistance was lower (15 +/- 1 vs. 30 +/- 9 mm Hg/L/min; p < 0.02). After reperfusion, the decrease in circulating leukocyte count fell by 35 +/- 3% in the control group and remained unchanged in the PTX group, and the leukocyte count per microscopic field in the transplanted lung was lower in the PTX group than in the control group (p < 0.02). In conclusion, PTX prevented IR lung endothelium injury and improved post-IR lung function by decreasing neutrophil lung sequestration, and this agent might be useful in clinical lung transplantation.

Animals↗
PubMed1994

Chest wall reconstruction following resection of large primary malignant tumors.

Reconstructive procedures following radical resection of large primary malignant chest wall tumors (PMCWT) continue to evolve. Between 1982 and 1993, 32 consecutive patients (18 males/14 females) with a median age of 47 years (range, 12-77) underwent radical resection for large (median 10 +/- 5.4 cm) PMCWTs arising either from the bone (n = 15) or soft tissues (n = 17) of the chest wall. Nine (28%) had previous surgical resection before referral. Sixteen (50%) required extensive skin excision. Twelve sternectomies (5 total and 7 partial) and 20 lateral chest wall resections were performed. In this latter group, 16 patients (80%) had at least three ribs resected. Resection extended to the lung (10 wedge resections, 2 lobectomies and 1 pneumonectomy) in 13 patients, diaphragm in 3, abdominal wall in 2, brachiocephalic and subclavian vessels in 5, superior vena cava in 1 and upper limb in 1. Stability of the chest wall was obtained with prosthetic material in 27 patients, including Marlex (n = 21), polytetrafluoroethylene (PTFE) (n = 4) and polyglactin (n = 2) meshes. After sternectomy, six patients had a methyl methacrylate mesh reinforcement while soft tissue reconstruction was carried out using the pectoralis major muscle (PM), either alone with skin advancement (n = 8) or as a myocutaneous flap in three males (unilateral n = 2, bilateral n = 1) and by a latissimus dorsi (LD) myocutaneous flap in one female. Muscle transposition was used to reconstruct defects of the lateral chest wall and included 10 LD, 6 PM and 2 serratus anterior (SA) muscles, with associated advancement of the diaphragm in two cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Reduction of ischemia-reperfusion injury by pentoxifylline in the isolated rat lung. Paris-Sud University Lung Transplantation Group.

Inhibition of pulmonary neutrophil sequestration attenuates ischemia-reperfusion (IR) lung injury. Pentoxifylline (PTX) reduced pulmonary sequestration of neutrophils and neutrophil-dependent lung injury in several experimental settings but has never been tested in IR models. We hypothesized that PTX may have a beneficial effect on IR lung injury as measured by the coefficient of filtration (Kfc) and may reduce IR-associated sequestration of neutrophils as assessed by lung myeloperoxidase (MPO) activity and by blood neutrophil count decrease during reperfusion. Three groups of isolated blood perfused rat lungs were studied: a time control group (n = 6) was perfused for 3 h, and two groups (n = 10) subjected to 1 h ischemia were treated with PTX or saline before a 2 h reperfusion. The increase in Kfc induced by IR was reduced fivefold by PTX compared with saline (+27 +/- 8% versus +112 +/- 12%, respectively; p < 0.001), and was similar to time controls (+9 +/- 9%). After IR, MPO and blood neutrophil count decrease were lower with PTX than with saline. Changes in Kfc were correlated to the percentage decrease in blood neutrophils during reperfusion. We conclude that PTX reduced rat lung IR microvascular injury. This effect may be mainly caused by decrease in lung sequestration of neutrophils during reperfusion.

Animals↗
PubMed1994

Heterotopic pig model for direct revascularization and venous drainage of tracheal allografts. Paris-Sud University Lung Transplantation Group.

A macrosurgical technique of thyrotracheal harvesting and direct revascularization with and without venous drainage in a heterotopic thyrotracheal and immunosuppressed allograft in the pig model is described. Harvesting included en bloc cervicothoracic exenteration of the aortic arch and its supraortic trunks, anterior vena cava, jugular veins, subclavian vessels, thyroid gland, cervicothoracic trachea, and esophagus. This technique conserves the tracheal arterial supply provided by either the right or left subclavian artery, directly or indirectly via the inferior thyroid artery, and venous return provided by the anterior vena cava, directly or indirectly via the descending cervical vein. In recipients, implantation included (1) arterial end-to-end anastomoses of the proximal and postscalenic stumps of donor's subclavian artery to the proximal and prescalenic stumps of recipient's subclavian artery; (2) end-to-side venous anastomosis of the donor's anterior vena cava to the recipient's brachiocephalic venous trunk; and (3) heterotopic implantation of the proximal and distal orifices of the grafted trachea into the neck. Ten adult Large White pigs underwent direct revascularization of a thyrotracheal allograft with (n = 6, group 1) and without (n = 4, group 2) venous drainage. All grafts of group 2 exhibited a venous infarction, extensive inferior thyroid artery thrombosis, and ischemic and suppurative thyrotracheal necrosis 1 to 2 days after transplantation. In group 1, the length of the grafted trachea and number of rings were 9.75 +/- 1.5 cm and 22.1 +/- 3.3, respectively; ischemic time was 236.3 +/- 338.3 minutes. Group 1 pigs were put to death 4 (n = 4) and 3 (n =2) weeks after transplantation. All tracheal grafts had histologically normal airway epithelium; isolated areas of necrotic ischemia of the chorion and submucosa lasted for the first 7 days after transplantation but disappeared after epithelial regeneration. Premortem angiograms showed that all vascular anastomoses were patent. Grafts were histologically normal at postmortem examinations and all but one had no rejection. This large animal model demonstrates that long tracheal allografts might be transplanted by means of this direct revascularization and venous drainage technique.

Animals↗