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Leishmania (Viannia) braziliensis is associated with distinct clinical manifestations such as cutaneous, mucocutaneous, and disseminated leishmaniasis. One factor related to this clinical spectrum is the structure of parasite populations. This study investigates in vivo binomial BALB/c-L. (V.) braziliensis exploring the phenotypic variability of subpopulations (Thor03, Thor10 and Thor22) of Thor strain, which have previously been described as causing distinct pattern infection in vitro. In the third week after infection, differences were observed in the development curves of the lesions, with larger lesions in the Thor03 and Thor10. At this point, lymph nodes of mice infected with the Thor03 and Thor10 exhibited lower IL-12 and TNF values compared to infection with the Thor strain and Thor22. The infection with the Thor10 showed highest values of the cytokine IL-10 compared to those infected with the Thor strain, Thor03 and Thor22. In addition, no statistical differences in parasite load wer observed in the footpad in seventh week post inoculation. In contrast, the higher parasite load values were observed in the lymph nodes for Thor03, Thor10 and Thor22 subpopulations. The data obtained here show these subpopulations cause transient and non-severe footpad lesions with parasite persistence in draining lymph nodes, although some mice developed non-healing lesions. Parasites isolated from the paws and lymph nodes of these animals were unable to establish persistent lesions in subsequent experimental infection assays. Collectively, these findings highlight consistent differences of infectionevolution and host immune response modulation, during infection among the Thor03, Thor10 and Thor22 subpopulations , all derived from a single strain., Competing Interests: Declaration of competing interest The authors declare they have no actual or potential competing financial interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Leishmania (Viannia) braziliensis Thor strain exhibits a heterogeneous composition comprised of subpopulations with varying levels of infectivity. Clonal subpopulations were previously obtained from the strain Thor by sorting single-parasites and proceeding cultivation. The subpopulations used in this study are named Thor03, Thor 10 and Thor22., Objectives: Phenotypic characteristics of the parasite, specially focusing on virulence factors and resistance to the antimicrobial mechanisms of macrophages, were investigate in these subpopulations., Methods: Cellular and molecular biology, as well as biochemistry approaches were applied to obtain the data analysed in this study., Findings: Relative quantification of gene expression was measured for calpain, cysteine protease B (CPB), and subtilisin proteases but no significant differences in these genes' expression among subpopulations was observed. However, subtilisin and CPB proteins were assessed as more abundant in Thor03 by fluorescence-labelled flow cytometry technique. Western Blotting assays, as semi-quantitative analysis in gel, showed higher concentrations of subtilisin (110 to 50 kDa) and CPB (40 to 18 kDa) in extract of intracellular amastigotes from subpopulations Thor03 and Thor10 and calpain (60 to 25 kDa) showed no significant differences among subpopulations. Complementary, higher trypanothione reductase activity was observed in Thor10 intracellular amastigotes and assays of susceptibility to hydrogen peroxide-inducing agents and nitric oxide donors conducted with promastigotes revealed greater resistance to in vitro oxidative stress induction for Thor10, followed by Thor03., Main Conclusions: The data obtained for the virulence factors explored here suggest how multiple coexisting phenotypic-distinct subpopulations may contribute in adaptability of a single L. (V.) braziliensis strain during infection in the host cells.

Objective: To describe the clinical, bronchoscopic, diagnostic, and therapeutic aspects between children and adults., Methods: This retrospective study compared the clinical and bronchoscopic characteristics of adults and children who underwent bronchoscopy for suspected foreign body aspiration. Data on sex, outpatient or emergency origin, bronchoscopy results, characteristics of the aspirated foreign body, and complications were analyzed., Results: In total, 108 patients were included in the analysis, with foreign body aspiration diagnosed in 69% of patients (30 children and 44 adults). In 91% of patients, there was a clinical history suggestive of aspiration. The mean age of the adults was 65.89 (±19.75) years, and that of the children was 2.28 (±1.78) years. Most of the children were under 3 years of age (80%), while adults were mostly 70 years of age or older (54.5%). Emergency care was more common among children than adults. The most common foreign bodies found in both age groups were organic bodies, primarily seeds. The most frequent locations of foreign bodies were the lobar bronchi in adults and the main bronchi in children. Flexible bronchoscopy is the primary method for diagnosis and treatment. Transient hypoxemia occurred particularly frequently in children (5%)., Conclusion: Foreign body aspiration, particularly that involving seeds, is more common in the extremes of age. A clinical history suggestive of aspiration is crucial in determining the need for bronchoscopy, which should be performed as early as possible. Flexible bronchoscopy is an effective and safe diagnostic technique.