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Predicting the occurrence probability of species is intrinsically dependent on the quality of the training dataset and, in particular, on the sample prevalence (i.e., the ratio between presences and absences). Whenever the number of presences and absences is not equal within the training dataset, the predictions deviate towards higher values as the sample prevalence increases and vice versa. As a result, probability models of species occurrence with different sample prevalence cannot be directly compared. The favourability concept was introduced to amend this limitation. Indeed, the favourability - i.e., the variation in the probability of occurrence regardless the sample prevalence - could reduce the degree of uncertainty when comparing species distributions despite different sample prevalences. To test this hypothesis, we simulated 50 virtual species and compared the predictive performance of four probability-based and favourability-based Species Distribution Models (GLM, GAM, RF, BRT) under a set of different prevalence values and sampling strategies (i.e, random and stratified sampling). Favourability-based models performed slightly better than probability-based models in predicting the species distribution over geographic space, confirming also their capability to reduce the variability of the predictions across different degrees of sample prevalence.

Background. Thoracic surgeons have limited experience with treating localized organizing pneumonia owing to its rare occurrence in routine clinical practice. Methods. We retrospectively investigated the clinicopathologic features of 21 patients with localized organizing pneumonia observed between 2001 and 2004. Results. There were 15 men and 6 women. Mean age was 63 years. Eight patients (38%) were symptomatic. Computed tomographic scan showed a single lesion in 17 patients ( 12 nodules and 5 masses) and bilateral lesions in 4. Wedge resection was performed in 16 patients and lobectomy in 5. There was no operative mortality. Followup was complete in all patients ( range, 2 to 46 months; median, 20 months). Surgery was curative in 15 of 17 patients with a single lesion, and no recurrence was observed ( p < 0.005). The remaining 2 patients with a single lesion ( 2 masses) had a local relapse with the appearance of nodular lesions in the residual parenchyma. Both these patients received steroids with resolution of the lesions. All 4 patients with bilateral lesions who underwent surgery for diagnostic purposes received steroids with improvement of the radiologic aspect in 3 and stabilization of the lesions in 1. Conclusions. Clinical and radiologic findings of localized organizing pneumonia are nonspecific, and this unusual entity is difficult to differentiate from a primary or metastatic tumor. Surgical resection allows both diagnosis and cure. However, considering the benignity of the lesion and the efficacy of steroids, major pulmonary resections should be avoided. RI ciriaco, paola/H-5716-2012

Objective: The purpose of this study was to evaluate the effect of lobectomy on pulmonary function in patients with chronic obstructive pulmonary disease. Methods: One hundred thirty-seven patients were analyzed; 49 had normal pulmonary function tests, and 88 had chronic obstructive pulmonary disease. Different functional parameter groups were identified: obstructive (forced expiratory volume in 1 second [FEV1], forced expiratory volume in 1 second/forced vital capacity [FEV1/FVC), and chronic obstructive pulmonary disease index), hyperinflation (residual volume and functional residual capacity), and diffusion (transfer factor of the lung for carbon monoxide). Also, the ratio between observed and predicted postoperative FEV, was calculated. Results: In patients with preoperative FEV, greater than 80% of predicted, postoperative FEV1/FVC slightly but not significantly decreased, and postoperative FEV, significantly decreased. In patients with preoperative FEV1 less than 65%, postoperative FEV, and FEV1/FVC significantly increased. In patients with preoperative FEV1/FVC greater than 70%, postoperative FEV, and FEV1/FVC significantly decreased. In patients with preoperative FEV1/FVC less than 70%, postoperative FEV1/FVC increased, and FEV1 remained unchanged. In patients with a chronic obstructive pulmonary disease index greater than 1.5, postoperative FEV1 and FEV1/FVC significantly decreased, whereas in patients with a chronic obstructive pulmonary disease index less than 1.5, postoperative FEV1/FVC significantly increased and FEV1 remained unchanged. In patients with residual volume and functional residual capacity greater than 115% and transfer factor of the lung for carbon monoxide less than 80% of predicted, postoperative FEV1 diminished less (not significant) compared with patients who had residual volume and functional residual capacity less than 115% (P = .0001). Observed postoperative/predicted postoperative FEV1 was higher if FEV1/FVC was less than 55% (1.46), if FEV1 was less than 80% of predicted (1.21), or if the chronic obstructive pulmonary disease index was less than 1.5 (1.17). Conclusions: Patients with mild to severe chronic obstructive pulmonary disease could have a better late preservation of pulmonary function after lobectomy than healthy patients. Objective: The purpose of this study was to evaluate the effect of lobectomy onpulmonary function in patients with chronic obstructive pulmonary disease.Methods: One hundred thirty-seven patients were analyzed; 49 had normal pulmonaryfunction tests, and 88 had chronic obstructive pulmonary disease. Differentfunctional parameter groups were identified: obstructive (forced expiratory volumein 1 second [FEV1], forced expiratory volume in 1 second/forced vital capacity[FEV1/FVC], and chronic obstructive pulmonary disease index), hyperinflation(residual volume and functional residual capacity), and diffusion (transfer factor ofthe lung for carbon monoxide). Also, the ratio between observed and predictedpostoperative FEV1 was calculated.Results: In patients with preoperative FEV1 greater than 80% of predicted, postoperativeFEV1/FVC slightly but not significantly decreased, and postoperative FEV1significantly decreased. In patients with preoperative FEV1 less than 65%, postoperativeFEV1 and FEV1/FVC significantly increased. In patients with preoperativeFEV1/FVC greater than 70%, postoperative FEV1 and FEV1/FVC significantlydecreased. In patients with preoperative FEV1/FVC less than 70%, postoperativeFEV1/FVC increased, and FEV1 remained unchanged. In patients with a chronicobstructive pulmonary disease index greater than 1.5, postoperative FEV1 andFEV1/FVC significantly decreased, whereas in patients with a chronic obstructivepulmonary disease index less than 1.5, postoperative FEV1/FVC significantly increasedand FEV1 remained unchanged. In patients with residual volume andfunctional residual capacity greater than 115% and transfer factor of the lung forcarbon monoxide less than 80% of predicted, postoperative FEV1 diminished less(not significant) compared with patients who had residual volume and functionalresidual capacity less than 115% (P .0001). Observed postoperative/predictedpostoperative FEV1 was higher if FEV1/FVC was less than 55% (1.46), if FEV1 wasless than 80% of predicted (1.21), or if the chronic obstructive pulmonary diseaseindex was less than 1.5 (1.17).Conclusions: Patients with mild to severe chronic obstructive pulmonary diseasecould have a better late preservation of pulmonary function after lobectomy thanhealthy patients.

Pericardial fat pads have been successfully used for many years by thoracic and cardiac surgeons for a number of applications. We recently used a pedicled and well-vascularized pericardial fat pad in a patient who underwent replacement of a distal aortic arch aneurysm with a Dacron tube graft, in order to avoid contact between the anastomoses and the oesophagus in an effort to reduce the risk of subsequent infection and fistula formation. This simple technique may provide a source of vital tissue that may be useful for protecting anastomoses after thoracic aortic surgery, particularly in cases requiring re-operation. To our knowledge the use of pericardial fat pads has not been previously reported in the English literature for this purpose Pericardial fat pads have been successfully used for many years by thoracic and cardiac surgeons for a number of applications. We recently used a pedicled and well-vascularized pericardial fat pad in a patient who underwent replacement of a distal aortic arch aneurysm with a Dacron tube graft, in order to avoid contact between the anastomoses and the oesophagus in an effort to reduce the risk of subsequent infection and fistula formation. This simple technique may provide a source of vital tissue that may be useful for protecting anastomoses after thoracic aortic surgery, particularly in cases requiring re-operation. To our knowledge the use of pericardial fat pads has not been previously reported in the English literature for this purpose. © 2003 Elsevier Science Ltd. All rights reserved.

Pleuropulmonary blastoma is a rare and aggressive neoplasm typically occurring in young children, even in newborns. Onset of the disease can be identified in the area of a previously diagnosed lung cyst. We report a case of a child previously diagnosed as having a right congenital lung cyst who had a pleuropulmonary blastoma developing in the same area. He underwent surgical resection of the neoplasm followed by chemotherapy. After 20 months he is alive and well. © 2008 The Society of Thoracic Surgeons.