Objective: To determine the efficacy of ethyl 2-cyanoacrylate adhesive in repairing the lung parenchyma after partial lobectomy in rats, in terms of hemostasis/aerostasis, scarring, and surgical time. Methods: The study involved 30 Wistar rats, randomly divided into five groups (one control group and four study groups). In the study groups, the lung parenchyma was repaired with either cyanoacrylate adhesive or surgical suture following resection of a small or large fragment (25% or 50%, respectively) of the left caudal lung lobe. Results: Surgical time and hemostasis time were shorter in the two groups treated with the adhesive than in the two submitted to suture. There were no significant differences among the groups regarding specific lung compliance. Adherences and inflammatory reactions were more severe in the groups submitted to suture. Conclusions: In this study, the use of cyanoacrylate adhesive helped reduce the surgical time and the intensity of inflammatory reactions, as well as preserving lung compliance. Cyanoacrylate adhesives should be considered an option for lung parenchyma repair, decreasing the risk of complications after partial lobectomy in humans.

Keywords: Lung; Pneumonectomy; Cyanoacrylates.

Purpose: To determine the effectiveness of alternative regimens for treating confirmed MDR TB cases in outpatient units: Methods: MDR TB cases were defined as culture isolation of M. tuberculosis resistant in vitro to at least rifampin/isoniazide and a third drug of standard regimens in Brazil, according to both the conventional method and the BACTEC system. Design: Multicentric non-randomized controlled clinical trial. From April 95 to December 97 187 patients were enrolled. As of April 98, there were 36 patients under treatment. The authors analyzed 149 patients that had an average 14 months of treatment duration. The regimens used were chosen according to sensitivity tests: 1) streptomycin (S)/ofloxacin (OFX)/terizidon (TZ)/ethambutol (E)/clofazimine (CZ) or capreomycin (CM)/OFX/TZ/CZ/E or amicacyn/OFX/TZ/E/CZ. Demography: Male, 68.4%; female, 31.5%; mean age-36.9 years; HIV prevalence 1.9%; primary resistance rate - 8%. Outcomes: cured-treated for 12 months with six months after two consecutive negative culture; abandoned-discontinued treatment and consultations; died - deaths due to TB after two months of treatment; failed - remained positive in culture throughout the 12 months. Results: 120 (79.5%) patients converted to negative culture within 3 months. Cured: 53%, failed 31%, died 6%, abandoned 10%. Conclusions: The major predictor to MDR TB in Brazil is previous irregular and/or incomplete treatment. Sputum conversion rate was high and favorable overall response was 53%. Clinical implications: Because TB is endemic in Brazil and the number of MDR cases due to acquired resistance is increasing, greater efforts are needed to implement supervised treatment in tuberculosis particularly for non compliant patients.

Keywords: Tuberculosis, treatment. Multidrug resistant tuberculosis.

Primary pulmonary lymphoma is rare. The most common histological type is the bronchus-associated lymphoid tissue lymphoma. This type of lymphoma has an indolent course and excellent response to therapy. One-third of all cases are diagnosed incidentally. However, due to the rarity of this disease, little is known about its natural history in terms of dissemination and evolution. Herein, we report the unusual case of a 61-year-old man who refused treatment after being diagnosed with bronchus-associated lymphoid tissue lymphoma and died 2 years later from massive lung infiltration without dissemination to other organs.

Keywords: Lung; Autopsy; Lymphoma.

Objective: To evaluate post-operative complications in living lobar lung transplant donors. Methods: Between September of 1999 and May of 2005, lobectomies were performed in 32 healthy lung transplant donors for 16 recipients. The medical charts of these donors were retrospectively analyzed in order to determine the incidence of post-operative complications and alterations in pulmonary function after lobectomy. Results: Twenty-two donors (68.75%) presented no complications. Among the 10 donors presenting complications, the most frequently observed complication was pleural effusion, which occurred in 5 donors (15.6% of the sample). Red blood cell transfusion was necessary in 3 donors (9.3%), and 2 donors underwent a second surgical procedure due to hemothorax. One donor presented pneumothorax after chest tube removal, and one developed respiratory infection. There were two intra-operative complications (6.25%): one donor required bronchoplasty of the middle lobe; and another required lingular resection. No intra-operative mortality was observed. Post-operative pulmonary function tests demonstrated an average reduction of 20% in forced expiratory volume in one second (p < 000.1) compared to pre-operative values. Conclusions: Lobectomy in living lung transplant donors presents high risk of post-operative complications and irreversible impairment of pulmonary function. Careful pre-operative evaluation is necessary in order to reduce the incidence of complications in living lobar lung transplant donors.

Keywords: Lung transplantation; Living donors; Pneumonectomy; Postoperative complications.

Objective: The reproduction of an experimental emphysema model in rats by intratracheal instillation of papain was proposed for the evaluation of lung volume reduction surgeries. Method: The study used orotracheal instillation of papain (20 mg/kg) dissolved in 0.9% saline solution. Forty days after instillation, animals underwent mechanical ventilation. Elastance and resistance of the respiratory system were measured, and the rats were sacrificed by having their lungs removed. The pulmonary tissue of the animals was qualitatively analyzed with hematoxylineosin staining and submitted to morphometric analysis for the measurement of the mean alveolar diameter. The pulmonary tissue was also subjected to resorcin-fuchsin staining for the identification of elastic fibers, which were quantified in alveolar septa by digital imaging. Results: In the animals instilled with papain, the histological analysis of the lungs showed pan-acinar emphysema, with rupture of alveolar septa and hyperdistention. Morphometric analysis showed higher mean values for mean alveolar diameter in the lungs of the animals submitted to papain (149.08 μm and 100.56 μm) as compared to the group receiving saline solution (64.08 μm and 75.90 μm). The quantification of elastic fibers of alveolar septa of papain-treated animals was 70% lower than in the animals receiving saline solution. Mechanic ventilation did not show differences in respiratory system resistance of animals receiving papain or saline solution. Respiratory system elastance was lower in the group receiving papain than in the group receiving saline solution, showing a functional status compatible with pulmonary emphysema, with decreased elasticity of the pulmonary tissue. Conclusion: The reproduction of an experimental model of pan-acinar pulmonary emphysema in rats was achieved by papain instillation through the respiratory tree with functional and morphologic evidences.

Keywords: Pulmonary emphysema. Experimental model. Papain. Rats. Drug instillations.

Acute respiratory distress syndrome (ARDS) is characterized by diffuse alveolar damage, and evolves progressively with three phases: exsudative, fibroproliferative, and fibrotic. In the exudative phase, there are interstitial and alveolar edemas with hyaline membrane. The fibroproliferative phase is characterized by exudate organization and fibroelastogenesis. There is proliferation of type II pneumocytes to cover the damaged epithelial surface, followed by differentiation into type I pneumocytes. The fibroproliferative phase starts early, and its severity is related to the patient's prognosis. The alterations observed in the phenotype of the pulmonary parenchyma cells steer the tissue remodeling towards either progressive fibrosis or the restoration of normal alveolar architecture. The fibrotic phase is characterized by abnormal and excessive deposition of extracellular matrix proteins, mainly collagen. The dynamic control of collagen deposition and degradation is regulated by metalloproteinases and their tissular regulators. The deposition of proteoglycans in the extracellular matrix of ARDS patients needs better study. The regulation of extracellular matrix remodeling, in normal conditions or in several pulmonary diseases, such as ARDS, results from a complex mechanism that integrate the transcription of elements that destroy the matrix protein and produce activation/inhibition of several cellular types of lung tissue. This review article will analyze the ECM organization in ARDS, the different pulmonary parenchyma remodeling mechanisms, and the role of cytokines in the regulation of the different matrix components during the remodeling process.

Keywords: Respiratory distress syndrome. Pulmonary alveoli/lesions. Extracellular matrix. Cytokines/ultrastructure.

Objective: This study aimed to investigate acute and chronic effects of varenicline on lung tissue in an experimental study. Methods: A total of 34 rats were randomly allocated into study (varenicline) and control groups. The rats were divided into two groups (i) control group, (ii) varenicline group. Then, the rats in the each group were sub‑divided equally in turn as acute (C1; V1) and chronic (C2; V2) ; all rats of acute and chronic groups were sacrificed under the anesthesia on the 45th day for acute group [C1 (n=5) and V1 (n=12)] and the 90th day for chronic group [C2 (n=5) and V2 (n=12)], respectively. Thus, biochemical and histopathological analysis were carried out. Results: Thirty four rats completed the study, 24 were in varenicline group and 10 were in control group. In chronic exposure to varenicline, oxidant levels comprising of malondialdehyde (MDA), and myeloperoxidase (MPO) increased and superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and glutathione peroxidase (GPx) levels, named as antioxidants, decreased significantly when compared to the control group. MDA and MPO levels were also significantly higher and SOD, CAT, GPx, GSH levels were also significantly lower in chronic varenicline group when compared to acute varenicline group. These findings were also supported by histopathological observations. Conclusion: This is the first study, which evaluated pulmonary effects of varenicline experimentally on an animal model. It was observed that chronic varenicline treatments cause inflammation and lung cell injury.

Keywords: Varenicline; Lung tissue; Oxidative stress; Pulmonary toxicity.

Because it has direct and indirect action on lung tissue, oleic acid (OA) has been used experimentally as a model of fat embolism and acute respiratory distress syndrome (ARDS). The aim of this study was to describe acute and chronic pulmonary lesions induced in rats by intravenous injection of OA. Male Wistar rats were injected a 0.05 ml dose of OA. Groups of 5 animals were sacrificed 2, 24, 48 hours, and 5, 10, 30, and 90 days after injection. Diffuse alveolar edema, foci of intra-alveolar hemorrhage, and foci of ischemic necrosis were observed by light microscopic from 2 to 48 hours. At this period of time, severe endothelial injuries and type II alveolar cell lesions were observed on electron microscopy. After the fifth day, no injury was observed and discrete morphological sequelae were found. The lungs of the animals sacrificed at the thirtieth and ninetieth days were identical to those of the control groups. The present model allows animal to survive, being suitable for studies on fat embolism and on ARDS.

Keywords: Oleic acid. Fat embolism. Acute respiratory distress syndrome, ARDS. Experimental model.

The increasing demand in transplantation research requires efficient and less expensive animal models in order to obtain reliable results that are reproducible in larger animal models and, ultimately, applied clinically. The model of unilateral left lung transplantation in rats has proven to be a useful alternative for those purposes. We demonstrate a technical modification of this model, which consists of the isolation and ligation of the contralateral (right) pulmonary artery, allowing blood circulation exclusively in the transplanted lung. This model is feasible and reproducible. However, the short survival time restricts the assessment of the transplanted lung to a maximum period of three hours.

Introduction: Surgical procedures requiring aortic occlusion have been associated with pulmonary reperfusion injury. The authors studied the pulmonary edema in a reperfusion injury model by aortic occlusion in rats. Material and methods: Thirty-three Wistar rats were anesthetized with intraperitoneal injection of sodium pentobarbital (20 mg/kg). Using a midline abdominal incision, the infra-renal aorta was isolated and the animals were randomized into three groups. Ischemia-reperfusion group (IRG, n = 5): rats that underwent 30 min of aorta occlusion and were followed during 120 min of reperfusion. Ischemia group (IG, n = 5): rats that underwent 30 min of aorta occlusion. Control group (CG, n = 5): rats that underwent sham operations without aorta occlusion and were followed during 150 min. Histopathologic examination of the right lung was performed. The pulmonary edema was studied by morphometric analysis and so was the leukocytes infiltration. Eighteen rats (6 rats in each group) were studied with respect to lung fresh/dry weight ratio. ANOVA was used to analyze the morphometric results and the lung fresh/dry weight ratio, with Bonferroni adjustment for paired multiple comparisons. Animals of the IRG presented more pulmonary edema than those of the IG and CG (0.24 vs. 0.17 and 0.17, p < 0.001). There was no difference between the groups regarding the lung fresh/dry weight ratio. There were more inflammatory cells in the lungs of the rats submitted to ischemia-reperfusion. The authors concluded that infra-renal abdominal aorta cross-clamping and unclamping are associated with pulmonary edema. This edema is not induced by elevation of the hydrostatic pressure due to the aortic occlusion, since it was not seen in animals that were only submitted to ischemia.

Keywords: ischemia, reperfusion, pulmonary edema, inbred strains rats

Objectives: Here, we investigated the effects of hyperventilation on acute lung injury (ALI) in spontaneously breathing rats. Methods: Wistar rats were randomized to receive either intraperitoneal lipopolysaccharides (LPS) or saline, and intravenous infusion of NH4Cl (to induce metabolic acidosis and hyperventilation) or saline. Four groups were established: control-control (C-C), control-hyperventilation (C-HV), LPS-control (LPS-C), and LPS-hyperventilation (LPS-HV). Venous blood gases were collected before and after NH4Cl infusion and analyzed to confirm the presence of metabolic acidosis and hyperventilation. After euthanasia, lung injury was assessed using the ALI score, morphometric quantification of perivascular edema, neutrophil counts in the bronchoalveolar lavage, and mRNA expression of biological markers in the lung tissue. Results: Hyperventilation induced inflammatory lung injury in previously healthy lungs and exacerbated injuries previously induced by LPS (ALI score: C-C=0.14 [IQR 0.12; 0.14]; C-HV=0.36 [IQR 0.31; 0.37]; LPS-C=0.51 [IQR 0.50; 0.54]; LPS-HV=0.58 [IQR 0.56; 0.62]; p<0.01). Perivascular edema, neutrophil counts in bronchoalveolar lavage, and amphiregulin mRNA expression were higher in the LPS-HV group compared to the control group. Conclusions: Hyperventilation increased inflammatory injury in rats with ALI during spontaneous ventilation. These results suggest that the impact of vigorous spontaneous breathing efforts on worsening inflammatory lung injury warrants further investigation.

Keywords: acute lung injury, acute respiratory distress syndrome, spontaneous breathing, hyperventilation, lung injury.

Objective: Surgical resection remains the gold standard treatment for bronchiectasis in patients who present with hemoptysis or suppuration, as well as in those who do not respond to clinical treatment. We sought to investigate the efficacy of sublobar resection (segmentectomy) and compare it with that of lobar resection (lobectomy) in patients with non-cystic fibrosis bronchiectasis. Methods: Patients undergoing lobectomy or segmentectomy between 2019 and 2023 were included in the study. We analyzed intraoperative complications and postoperative outcomes, including length of hospital stay, length of ICU stay, and disease recurrence. Results: There was no significant difference between the lobectomy and segmentectomy groups regarding the occurrence of intraoperative complications such as bleeding > 1000 ml, cardiogenic shock, and ventilatory instability (p > 0.999). However, the frequency of complications was significantly lower in the segmentectomy group than in the lobectomy group (p = 0.016). Hospital stays were longer in the lobectomy group than in the segmentectomy group (16 days vs. 5 days; p = 0.027), as were ICU stays (7 days vs. 1 day; p = 0.006). There was no significant difference between the lobectomy and segmentectomy groups regarding the recurrence rate (p = 0.541). Conclusions: Early identification of bronchiectasis patients who are candidates for surgical resection is essential because those who are identified as such early on are candidates for parenchyma-sparing resections, which are similar to lobar resections in terms of disease control and lead to shorter hospital stays and better postoperative outcomes.

Keywords: Bronchiectasis; Thoracic surgery; Disease-free survival.

Background: Lobectomy is still considered the most effective method of controlling primary lung tumors. Method: During the period from 1995 to 2000, 733 cases of non-small cell bronchial carcinoma. After clinical evaluation and surgical staging, 191 patients were submitted to surgical resection. Of those 191 surgeries, 63 were for locally advanced tumors and 128 (69 segmentectomies and 59 lobectomies) for primary tumors. Post-operative FEV1 of at least 800 ml was used as a measure of surgical success. Extended segmentectomies, in which the resection passes the intersegmental line, including the parenchyma of the adjoining segment, were used. Results: Among the 128 patients with primary tumors, there were 3 deaths and 10 patients fell out of contact. Therefore, 62 segmentectomies and 53 lobectomies were evaluated. There were 72 adenocarcinomas and 43 epidermoid carcinomas. The 5-year survival of lobectomy patients was 80% (T1N0), 72.7% (T2N0), 50% (T1N1) and 31.8% (T2N1), whereas that of segmentectomy patients was 80% (T1N0), 66.6% (T2N0), 41.1% (T1N1) and 30% (T2N1) (p > 0.05). Tumor size and enlarged interlobar lymph nodes were prognostically significant (p < 0.001), although method of resection influenced neither survival nor local or remote recurrence (p > 0.05). Conclusion: Extended segmentectomy represents an alternative treatment for primary tumors in patients with limited lung reserve.

Keywords: Lung Neoplasms, surgery. Pulmonary Surgical Procedures. Carcinoma, Non-Small-Cell Lung.

Small animal models are particularly suitable for lung preservation studies, because they are simple and cost-effective. This brief communication focuses on the technical description of an ex vivo lung perfusion model in rats by means of a commercially available apparatus, which was the first to be installed in a thoracic surgery research laboratory in Brazil. The model and its preparation, together with its applications for lung preservation studies, are described in detail. All technical details can also be seen in a video posted on the website of the Brazilian Journal of Pulmonology.

Keywords: Lung transplantation; Reperfusion injury; Rats; Models, animal.

We assessed the effects of lodenafil on hemodynamics and inflammation in the rat model of monocrotaline-induced pulmonary hypertension (PH). Thirty male Sprague-Dawley rats were randomly divided into three groups: control; monocrotaline (experimental model); and lodenafil (experimental model followed by lodenafil treatment, p.o., 5 mg/kg daily for 28 days) Mean pulmonary artery pressure (mPAP) was obtained by right heart catheterization. We investigated right ventricular hypertrophy (RVH) and IL-1 levels in lung fragments. The number of cases of RVH was significantly higher in the monocrotaline group than in the lodenafil and control groups, as were mPAP and IL-1 levels. We conclude that lodenafil can prevent monocrotaline-induced PH, RVH, and inflammation.

Keywords: Hypertension, pulmonary; Monocrotaline; Interleukin-1.