Abstract Objective: To determine the levels of alpha-1 antitrypsin (AAT) and the presence of S and Z alleles in patients with chronic respiratory symptoms. Methods: Patients with chronic cough and dyspnea were submitted to clinical evaluation, pulmonary function tests, high-resolution computed tomography, nephelometric determination of AAT and determination of S and Z alleles by polymerase chain reaction. Smoking and AAT levels were considered the dependent variables. Results: Of the 89 patients included in the study, 44 were female. The mean age was 51.3 ± 18.2 years. The S and Z alleles were detected in 33.3% and 5.7%, respectively, and the gene frequency was 0.16 and 0.028, respectively. Two patients were SZ heterozygotes (AAT levels ≤ 89 mg/dL). The patients were divided into groups based on AAT level: ≤ 89 mg/­dL (deficiency, no group); 90-140 mg/dL (intermediate, Group 1, n = 30); and ≥ 141 mg/dL (normal, Group 2, n = 57). The frequency of smokers was the same in both groups, although tobacco intake was greater in Group 2. The S allele was present in 13 and 14 patients in Groups 1 and 2, respectively, whereas the Z allele was present in 2 and 1 patient in the same groups. There was no difference in the results of pulmonary function tests or in the frequency of bronchiectasis or emphysema between the two groups. Spirometric values and AAT levels were similar in smokers and nonsmokers. Bronchiectasis was more common in nonsmokers, and emphysema was more common in smokers. Conclusions: Thirty patients presented AAT levels lower than the mean values found in patients with the MM or MS genotype, and this fact could not be explained by an increased frequency of S and Z alleles.

Keywords: Alpha 1-antitrypsin; Emphysema: Lung diseases; Alleles.

Objective: The shortage of viable lungs is still a major obstacle for transplantation. Trauma victims who represent potential lung donors commonly present hypovolemic shock leading to pulmonary inflammation and deterioration and rejection after transplantation. Seeking to improve lung graft, new approaches to donor treatment have been tested. This study focuses on treatment with mesenchymal stem cells (MSCs) or soluble factors produced by MSCs (FS-MSC) using a rat model for lung donors after hemorrhagic shock. Methods: Forty-eight rats were divided into four groups: Sham (n=12), animals without induction of hypovolemic shock; Shock (n=12), animals submitted to hypovolemic shock (mean arterial pressure 40 mmHg); MSC (n=12), animals submitted to hypovolemic shock and treated with MSCs, and FS (n=12), animals submitted to hypovolemic shock and treated with FS-MSC. The animals were subjected to a 50-minute hypovolemic shock (40 mmHg) procedure. The treated animals were monitored for 115 minutes. We performed histopathology of lung tissue and quantification of inflammatory markers (TNF-a, IL-1ß, IL-6, IL-10, iCAM and vCAM) in lung tissue and peripheral blood leukocytes (PBLs). Results: Hemorrhagic shock resulted in higher PBLs and neutrophil infiltrate in the lungs. FS animals had lower neutrophil density comparing with Shock and MSC animals (p<0.001). No differences in the cytokine levels in lung tissue were observed between the groups. Conclusions: The lungs of rats submitted to hemorrhagic shock and treated with FS-MSC showed reduced inflammation indicated in a decrease in lung neutrophil infiltrate.

Keywords: Lung transplantation; Tissue donors; Hypovolemic shock; Mesenchymal cells; Inflammation.

Objective: To assess the influence of the COVID-19 pandemic on hospital admissions (HA), intra-hospital deaths (HD), and intra-hospital lethality rates (HL) related to respiratory diseases (RD) other than COVID-19 in Brazil. Methods: This observational time-series study was conducted through comparative analyses of the HA, HD, and HL related to non-COVID-19 RD registered between March and December 2020 by the Brazilian Unified Public Health System on the DataSUS Tabnet platform, using as reference the values recorded in the same period of 2019 and those projected by linear regression methods for 2020, considering the period from 2015 to 2019. The adopted statistical significance level was 5% (p < 0.05). Results: Compared to 2019, in 2020, there was a 42% decrease in HA and a 7.4% decrease in total HD related to non-COVID-19 RD, followed by a 60% increase in HL associated with this group of diseases. The HA and HL registered in 2020 differed significantly from the projected trend for that year by linear regression (p < 0.05). Of note, a significant reduction in hospitalizations due to asthma (-46%), chronic obstructive pulmonary disease (-45%), bronchiectasis (-54%), pneumonia (-46%), and acute bronchitis (-73%) was observed. Conclusions: During the first 8 months of the pandemic, there was a decline in HA and an increase in HL related to non-COVID-19 RD in Brazil, which can hypothetically reflect logistical challenges and delays in the management of this group of diseases.

Keywords: Pulmonary disease, COVID-19, non-COVID-19, Hospitalization, Mortality.

Mycobacterium tuberculosis is one of the most successful human pathogens. Highly virulent strains, which are more easily transmitted than are less virulent strains, elicit variable immune responses. We evaluated the Th1 responses (IFN-γ production) in healthy volunteers after stimulation with various strains. Our results show that the individuals with negative tuberculin skin test (TST) results were not necessarily naive to all of the strains tested, whereas individuals with positive TST results did not respond to all of the strains tested. Drug-resistant strains induced a lower mean level of IFN-γ production than did drug-sensitive strains. One possible practical application of this finding would be for the prediction of responses to treatment, in which it might be advantageous to have knowledge of the estimated IFN-γ production elicited by a specific isolated strain.

Keywords: Tuberculosis; Polymorphism, restriction fragment length; Mycobacterium tuberculosis; Immunity, cellular; Interferon-gamma.