Mauro Canzian

The renin-angiotensin system is upregulated in the cortex and hippocampus of patients with temporal lobe epilepsy related to mesial temporal sclerosis.

Purpose: As reported by several authors, angiotensin II (AngII) is a proinflammatory molecule that stimulates the release of inflammatory cytokines and activates nuclear factor κB (NFκB), being also associated with the increase of cellular oxidative stress. Its production depends on the activity of the angiotensin converting enzyme (ACE) that hydrolyzes the inactive precursor angiotensin I (AngI) into AngII. It has been suggested that AngII underlies the physiopathological mechanisms of several brain disorders such as stroke, bipolar disorder, schizophrenia, and disease. The aim of the present work was to localize and quantify AngII AT1 and AT2 receptors in the cortex and hippocampus of patients with temporal lobe epilepsy related to mesial temporal sclerosis (MTS) submitted to corticoamygdalohippocampectomy for seizure control.

PoSt-mortEm hIStoLogICAL PuLmoNAry ANALySIS IN PAtIENtS wIth hIV/AIDS

OBJECTIVES Certain aspects of pulmonary pathology observed in autopsies of HIV/AIDS patients are still unknown. This study considers 250 autopsies of HIV/AIDS patients who died of acute respiratory failure and describes the demographic data, etiology, and histological pulmonary findings of the various pathologies. METHODS The following data were obtained: age, sex, and major associated diseases (found at the autopsy). Pulmonary histopathology was categorized as: diffuse alveolar damage; pulmonary edema; alveolar hemorrhage; and acute interstitial pneumonia. Odds ratio of the HIV/AIDS-associated diseases developing a specific histopathological pattern was determined by logistic regression. RESULTS A total of 197 men and 53 women were studied. The mean age was 36 years. Bacterial bronchopneumonia was present in 36% (91 cases) and Pneumocystis jiroveci pneumonia in 27% (68) of patients. Pulmonary histopathology showed acute interstitial pneumonia in 40% (99), diffuse alveolar damage in 36% (89), pulmonary edema in 13% (33), and alveolar hemorrhage in 12% (29) of patients. Multivariate analysis showed a significant and positive association between Pneumocystis jiroveci pneumonia and acute interstitial pneumonia (Odds ratio, 4.51; 95% CI, 2.46 – 8.24; p < 0.001), severe sepsis and/or septic shock and diffuse alveolar damage (Odds ratio, 3.60; 95% CI, 1.78 –7.27; p < 0.001), and cytomegalovirus and acute interstitial pneumonia (Odds ratio, 2.22; 95% CI, 1.01 – 4.93; p = 0.05). CONCLUSIONS This report is the first autopsy study to include demographic data, etiologic diagnosis, and respective histopathological findings in patients with HIV/AIDS and acute respiratory failure. Further studies are necessary to elucidate the complete pulmonary physiopathological mechanism involved with each HIV/AIDS-associated disease.

Histologic and functional evaluation of lungs reconditioned by ex vivo lung perfusion

BACKGROUND Only about 15% of donor lungs are considered suitable for transplantation (LTx). Ex vivo lung perfusion (EVLP) has been developed as a method to reassess and repair damaged lungs. We report our experience with EVLP in non-acceptable donor lungs and evaluate its ability to recondition these lungs. METHODS We studied lungs from 16 brain-dead donors rejected for LTx. After harvesting, the lungs were stored at 4°C for 10 hours and subjected to normothermic EVLP with Steen Solution (Vitrolife, Göteborg, Sweden) for 60 minutes. For functional evaluation, the following variables were assessed: partial pressure of arterial oxygen (Pao(2)), pulmonary vascular resistance (PVR), and lung compliance (LC). For histologic assessment, lung biopsy was done before harvest and after EVLP. Tissue samples were examined under light microscopy. To detect and quantify apoptosis, terminal deoxynucleotide transferase-mediated deoxy uridine triphosphate nick-end labeling assay was used. RESULTS Thirteen lung donors were refused for having impaired lung function. The mean Pao(2) obtained in the organ donor at the referring hospital was 193.7 mm Hg and rose to 489 mm Hg after EVLP. During EVLP, the mean PVR was 652.5 dynes/sec/cm(5) and the mean LC was 48 ml/cm H(2)O. There was no significant difference between the mean Lung Injury Score before harvest and after EVLP. There was a trend toward a reduction in the median number of apoptotic cells after EVLP. CONCLUSIONS EVLP improved lung function (oxygenation capacity) of organs considered unsuitable for transplantation. Lung tissue structure did not deteriorate even after 1 hour of normothermic perfusion.

Lung transplantation for pulmonary alveolar microlithiasis: a case report

Pulmonary alveolar microlithiasis (PAM) is a rare idiopathic lung disease, characterized by the formation and accumulation of tiny, round corpuscles called “microliths” that consist primarily of calcium and phosphorus mixed with small amounts of magnesium and aluminum1. Most of the reported cases are of patients between 20 and 40 years of age. Autosomal recessive inheritance has been suggested to be a possible cause of the disease. Clinical features vary, and some patients may be asymptomatic for a long time until pulmonary function testing begins to demonstrate lung impairment along with progressive fibrosis and the development of a restrictive ventilatory defect culminating in cardiorespiratory decompensation.2 Currently, there is no medical therapy capable of definitively changing the progression of the disease. Lung transplantation is required once end-stage lung disease is established. To date, seven patients have received lung transplantation for this condition. We report a successful case of bilateral sequential lung transplantation in a patient with PAM.

Semiquantitative assessment of surgical lung biopsy: predictive value and impact on survival of patients with diffuse pulmonary infiltrate

PURPOSE Surgical lung biopsy has been studied in distinct populations, mostly going beyond clinical issues to impinge upon routine histopathological diagnostic information in diffuse infiltrates; however, detailed tissue analyses have rarely been performed. The present study was designed to investigate the prognostic contribution provided by detailed tissue analysis in diffuse infiltrates. METHODS Medical records and surgical lung biopsies from the period of 1982 to 2003 of 63 patients older than 18 years with diffuse infiltrates were retrospectively examined. Lung parenchyma was histologically divided into 4 anatomical compartments: interstitium, airways, vessels, and alveolar spaces. Histological changes throughout these anatomical compartments were then evaluated according to their acute or chronic evolutional character. A semiquantitative scoring system was applied to histologic findings to evaluate the intensity and extent of the pathological process. We applied logistic regression to predict the risk of death associated with acute and chronic histological changes and to estimate the odds ratios for each of the independent variables in the model. RESULTS Impact on survival was found for male gender (P = 0.03), presence of diffuse alveolar damage (P = 0.001), and chronic histological changes (P = 0.0004) on biopsy. Thus, being male was associated with a slightly lower risk (O.R. = 0.18; P=0.03) of dying than being female. Death risk was increased 17 times in the presence of acute histological changes such as diffuse alveolar damage and 2.5 times in the presence of chronic histological changes. CONCLUSION Detailed analysis of histological specimens can provide more than a nosological diagnosis: this approach can provide valuable information concerning prognosis.

Estado atual e aplicabilidade clínica da punção aspirativa por agulha guiada por ultrassom endobrônquico

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) has played a key role in the diagnosis of mediastinal, paratracheal, and peribronchial lesions, as well as in lymph node staging for lung cancer. Despite its minimally invasive character, EBUS-TBNA has demonstrated a diagnostic yield comparable with that of established surgical methods. It has therefore gained credibility and has become a routine procedure at various referral centers. A successful EBUS-TBNA procedure requires careful planning, which includes a thorough review of the radiological imaging and special care during specimen collection and preparation, as well as technical expertise, experience with the procedure itself, and knowledge of the potential complications inherent to the procedure. The most common indications for EBUS-TBNA include lymph node staging for lung cancer and the diagnostic investigation of mediastinal/hilar masses and lymph node enlargement. Recently, tumor biomarkers in malignant samples collected during the EBUS-TBNA procedure have begun to be identified, and this molecular analysis has proven to be absolutely feasible. The EBUS-TBNA procedure has yet to be included on the Brazilian Medical Association list of medical procedures approved for reimbursement. The EBUS-TBNA procedure has shown to be a safe and accurate tool for lung cancer staging/restaging, as well as for the diagnosis of mediastinal, paratracheal, and peribronchial lesions/lymph node enlargement

Comparação de dois modelos experimentais de hipertensão pulmonar

OBJECTIVE: To compare two models of pulmonary hypertension (monocrotaline and monocrotaline+pneumonectomy) regarding hemodynamic severity, structure of pulmonary arteries, inflammatory markers (IL-1 and PDGF), and 45-day survival. METHODS: We used 80 Sprague-Dawley rats in two study protocols: structural analysis; and survival analysis. The rats were divided into four groups: control; monocrotaline (M), pneumonectomy (P), and monocrotaline+pneumonectomy (M+P). In the structural analysis protocol, 40 rats (10/group) were catheterized for the determination of hemodynamic variables, followed by euthanasia for the removal of heart and lung tissue. The right ventricle (RV) was dissected from the interventricular septum (IS), and the ratio between RV weight and the weight of the left ventricle (LV) plus IS (RV/LV+IS) was taken as the index of RV hypertrophy. In lung tissues, we performed histological analyses, as well as using ELISA to determine IL-1 and PDGF levels. In the survival protocol, 40 animals (10/group) were followed for 45 days. RESULTS: The M and M+P rats developed pulmonary hypertension, whereas the control and P rats did not. The RV/LV+IS ratio was significantly higher in M+P rats than in M rats, as well as being significantly higher in M and M+P rats than in control and P rats. There were no significant differences between the M and M+P rats regarding the area of the medial layer of the pulmonary arteries; IL-1 and PDGF levels; or survival. CONCLUSIONS: On the basis of our results, we cannot conclude that the monocrotaline+pneumonectomy model is superior to the monocrotaline model.

Histological Evaluation of Biocompatibility of Lyophilized Bovine Pericardium Implanted Subcutaneously in Rats

This article aims at investigating in vivo evaluation of lyophilization procedure on the biocompatibility of bovine pericardium treated with glutaraldehyde (GA). The bovine pericardium was fixed with 0.5% glutaraldehyde during 10 days and preserved in 4% formaldehyde (FA). Two groups of samples were prepared from treated membranes: Group 1, nonlyophilized samples and Group 2, lyophilized samples. Male Sprague-Dawley rats (4 weeks after birth) were anesthetized (pentobarbital sodium 25 mg/kg of body weight) and in each one were implanted subcutaneously in the dorsal region a sample from Group 1 and another from Group 2. These samples were explanted after 30 days for histological analysis. No intercurrences took place after the surgery. No differences (P > 0.05) in the calcification, granulomatous reaction, mononuclear infiltration, and granulation tissue development was observed between both groups. The implanted lyophilized samples presented a trend for a reduced inflammatory reaction. Lyophilization of the bovine pericardium does not seem to increase the above listed tissue reaction.

Relationship between fluid-attenuated inversion-recovery (FLAIR) signal intensity and inflammatory mediator's levels in the hippocampus of patients with temporal lobe epilepsy and mesial temporal sclerosis

We investigated a relationship between the FLAIR signal found in mesial temporal sclerosis (MTS) and inflammation. Twenty nine patients were selected through clinical and MRI analysis and submitted to cortico-amygdalo-hippocampectomy to seizure control. Glutamate, TNFα, IL1, nitric oxide (NO) levels and immunostaining against IL1β and CD45 was performed. Control tissues (n=10) were obtained after autopsy of patients without neurological disorders. The glutamate was decreased in the temporal lobe epilepsy (TLE) -MTS group (p<0.001), suggesting increased release of this neurotransmitter. The IL1β and TNFα were increased in the hippocampus (p<0.05) demonstrating an active inflammatory process. A positive linear correlation between FLAIR signal and NO and IL1β levels and a negative linear correlation between FLAIR signal and glutamate concentration was found. Lymphocytes infiltrates were present in hippocampi of TLE patients. These data showed an association between hippocampal signal alteration and increased inflammatory markers in TLE-MTS.

Kallikrein 1 is overexpressed by astrocytes in the hippocampus of patients with refractory temporal lobe epilepsy, associated with hippocampal sclerosis

Kallikrein 1 (hK1) is a tissue enzyme responsible for kinin release in inflammatory cascade. This study was delineated to study the distribution and the co-localization of hK1 and kinin B1 and B2 receptors with glial and/or neuronal proteins markers, in the hippocampus of patients with refractory temporal lobe epilepsy, associated with hippocampal sclerosis (TLE-HS), comparing with control tissues. Hippocampal levels of KLK1 mRNA were also measured. hK1, kinin B1 and B2 receptors, NeuN and GFAP were analyzed using immunohistochemistry and confocal microscopy and KLK1 mRNA was quantified with real time PCR. Increased expression of hK1 by astrocytes co-localized with GFAP was found, contrasting with kinin B1 and B2 receptors, which were co-localized with NeuN in the sclerotic hippocampus. In addition, KLK1 mRNA was also up-regulated in same tissues. These data suggest an overexpression of kallikrein-kinin system and a neuron-glia interaction in the inflammatory process present in refractory TLE-HS.