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Several disturbances in T-cell mediated immunity have been described during aging, but immunosenescence of the B-cell compartment is less well elucidated. The peripheral blood B-cell compartment (CD19+) can be split into six main subpopulations according to the cell surface markers IgD, CD27, CD24, and CD38: Transitional, naïve, unswitched, switched, double negative and plasmablasts. We thus aimed to verify whether shifts in these subsets occur during healthy and pathological aging. We recruited three groups of aged people (> 60 years old), healthy, COPD patients, and smokers without altered pulmonary function test, and a fourth group of individuals 18-40 years old (youngs). Total B-cells percentage and absolute number were similar among the healthy aged, COPD patients, and youngs, but the smokers showed significantly higher absolute numbers. While all six B-cell subset percentages were comparable among the healthy aged, COPD patients, and youngs, smokers showed significantly higher percentages of switched B-cells and reduced naïve B-cells than the other three groups, resulting in an inverted naive:switched ratio. Analysis of the cell subset absolute numbers showed a similar trend. Overall, our results suggest that aging drives milder alterations in the distribution of peripheral blood B-cell subpopulations than in the T-cell compartment. We suggest that it is the T-cell immunosenescence that most contributes to the poor humoral immune responses in the elderly, vaccine responses included. Surprisingly it was the smokers who showed significant alterations when compared with the youngs, healthy aged, and aged COPD patients, probably as a result of the chronic immune stimulation described in active smoking subjects.

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Male researchers dominate scientific production in science, technology, engineering, and mathematics (STEM). However, potential mechanisms to avoid this gender imbalance remain poorly explored in STEM, including ecology and evolution areas. In the last decades, changes in the peer-review process towards double-anonymized (DA) have increased among ecology and evolution (EcoEvo) journals. Using comprehensive data on articles from 18 selected EcoEvo journals with an impact factor >1, we tested the effect of the DA peer-review process in female-leading (i.e., first and senior authors) articles. We tested whether the representation of female-leading authors differs between double and single-anonymized (SA) peer-reviewed journals. Also, we tested if the adoption of the DA by previous SA journals has increased the representativeness of female-leading authors over time. We found that publications led by female authors did not differ between DA and SA journals. Moreover, female-leading articles did not increase after changes from SA to DA peer-review. Tackling female underrepresentation in science is a complex task requiring many interventions. Still, our results highlight that adopting the DA peer-review system alone could be insufficient in fostering gender equality in EcoEvo scientific publications. Ecologists and evolutionists understand how diversity is important to ecosystems' resilience in facing environmental changes. The question remaining is: why is it so difficult to promote and keep this "diversity" in addition to equity and inclusion in the academic environment? We thus argue that all scientists, mentors, and research centers must be engaged in promoting solutions to gender bias by fostering diversity, inclusion, and affirmative measures.

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Este estudo analisou as condições de permanência e o perfil sociodemográfico-familiar de estudantes do curso noturno de Odontologia, em Universidade Pública do sul do Brasil. Utilizou dados de pesquisa observacional transversal, realizada pelo autopreenchimento de instrumento online. Todos os 175 estudantes matriculados no curso noturno, primeiro semestre de 2019, foram convidados a participar do estudo. As questões fechadas foram analisadas pela estatística descritiva e as abertas pela análise temática de conteúdo. Participaram da pesquisa 55 estudantes. Em sua maioria, eram mulheres, de 25 a 35 anos, brancas, solteiras, sem filhos, residentes na cidadeem que se localiza a Instituição e cursaram ensino fundamental e médio em escola pública; 50,9% trabalham, mas dependem de apoio familiar para seu sustento e 63,6% possuem renda individual mensal de até 2 salários mínimos. As barreiras associadas à permanência do estudante no curso foram questões financeiras, aspectos organizacionais da Universidade/curso,a condição de ser estudante-trabalhador, conhecimento do corpo docente sobre o perfil dos estudantes do noturno, segurança em torno do campus e tempo de duração do curso. O auxílio financeiro para compra de materiais odontológicos foi reconhecido como estratégia facilitadora da permanência no curso. Estudantes recomendam como estratégias para fortalecer a permanência, a flexibilização de pré-requisitos e horários de chegada nas aulas, acompanhamento de disciplinas no turno diurno, disciplinas/atividades deeducação a distância, maior oferta de atividades extracurriculares em dias/horários considerando o estudante-trabalhador e acompanhamento psicológico. O curso noturno tem possibilitado o acesso do estudante trabalhador na educação superior em Odontologia.Barreiras e facilitadores da permanência foram identificados e devem ser permanentemente analisados (AU).

Este estudio analizó las condiciones de permanencia y el perfil sociodemográfico-familiar de estudiantes del curso nocturno de Odontología, en una Universidad Pública del sur de Brasil. Utilizó datos de una encuesta observacional transversal, realizada porautocompletado de un instrumento en línea. Todos los 175 estudiantes matriculados en el curso vespertino, primer semestre de 2019, fueron invitados a participar en el estudio. Las preguntas cerradas se analizaron mediante estadística descriptiva y las preguntas abiertas mediante análisis de contenido temático. Participaron en la investigación 55 estudiantes. En su mayoría eran mujeres, entre 25 y 35 años, blancas, solteras, sin hijos, residentes en la ciudad donde se encuentra la Institución y que habían cursado estudios primarios y secundarios en una escuela pública; 50,9% trabaja, pero depende del apoyo familiar para su sustento y el 63,6% tiene un ingreso mensual individual de hasta 2 salarios mínimos. Las barreras asociadas a la permanencia del estudiante en el curso fueron aspectos económicos, aspectos organizativos de la Universidad/curso, la condición de estudiante-trabajador, conocimiento de la facultad sobre el perfil de los estudiantes nocturnos, seguridad en los alrededores del campus y duración de la carrera. La ayuda financiera para la compra de materiales dentales fue reconocida como una estrategia facilitadora para la permanencia en el curso. Los estudiantes recomiendan, como estrategias para fortalecer la permanencia, la flexibilización de requisitos y horarios de llegada a clases, seguimiento de asignaturas en turno diurno, asignaturas/actividades de educación a distancia, mayor oferta de actividades extracurriculares en días/horarios considerando al estudiante-trabajador y seguimiento psicológico. El curso nocturno ha permitido a los estudiantes trabajadores acceder a la educación superior en Odontología. Se identificaron barreras y facilitadores de la permanencia y deben ser permanentemente analizados (AU).

This study analyzed the permanence conditions and the sociodemographic-family profile of students of the evening Dentistry course offered by a Public University in southern Brazil. It used data from a cross-sectional observational survey carried out through self-completion of an online instrument. All 175 students enrolled in the evening course in the first semester of 2019 were invited to participate in the study. Closed questions were analyzed using descriptive statistics and open questions were interpreted using thematic content analysis. A total of 55 students participated in the research. Most of them were women, aged between 25 and 35 years, white, single, without children, resident in the city where the Institution is located, and who attended primary and secondary education in public schools. In addition, 50.9% work but depend on family support for their livelihood, and 63.6% have an individual monthly income of up to 2 minimum salaries. The barriers associated with student's permanence in the course were financial issues, organizational aspects of the University/course, the condition of being a working student, teachers' familiarization with the profile of evening students, security around the campus, and course duration. Financial aid for the purchase of dental materials was recognized as a facilitating strategy for permanence in the course. Students recommend, as strategies to strengthen permanence, the flexibility of curriculum prerequisites and arrival times in classes, attending disciplines in the day period, distance education disciplines/activities, a greater offer of extracurricular activities on days/times that take into account the working student, and psychological follow-up. The evening course has enabled working students to access higher education in Dentistry. Barriers to and facilitators of permanence were identified and mustbe permanently analyzed (AU).

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BACKGROUND: COPD is associated with an abnormal lung immune response that leads to tissue damage and remodeling of the lung, but also to systemic effects that compromise immune responses. Cigarette smoking also impacts on innate and adaptative immune responses, exerting dual, pro- and anti-inflammatory effects. Previously, we showed that COPD patients presented accelerated telomere shortening and decreased telomerase activity, while, paradoxically, cigarette-smokers exhibited preserved telomerase activity and slower rate of telomere shortening. RESULTS: Here, we evaluated the naive, CM, EM and TEMRA subsets of TCD4 and TCD8 cells according to the expression of CCR7/CD45RA. We compared age-matched COPD patients, cigarette-smokers without clinical-laboratory evidence of pulmonary compromise, and healthy individuals. They were additionally compared with a group of young adults. For each subset we analysed the expression of markers associated with late differentiation, senescence and exhaustion (CD27/CD28/CD57/KLRG1/PD1). We show that COPD patients presented a drastically reduced naive cells pool, and, paradoxically, increased fractions of naive cells expressing late differentiation, senescence or exhaustion markers, likely impacting on their immunocompetence. Pronounced phenotypic alterations were also evidenced in their three memory T-cell subsets compared with the other aged and young groups, suggesting an also dysfunctional memory pool. Surprisingly, our smokers showed a profile closer to the Healthy aged than COPD patients. They exhibited the usual age-associated shift of naive to EM TCD4 and TCD8 cells, but not to CM or TEMRA T-cells. Nonetheless, their naive T-cells phenotypes were in general similar to those of the Youngs and Healthy aged, suggesting a rather phenotypically preserved subset, while the memory T-cells exhibited increased proportions of cells with the late-differentiation or senescence/exhaustion markers as in the Healthy aged. CONCLUSION: Our study extends previous findings by showing that COPD patients have cells expressing a full range of late differentiated, senescent or exhausted phenotypes encompassing all TCD4 and TCD8 subsets, consistent with a premature immunosenescence phenotype. Surprisingly, the smokers group's results suggest that moderate to heavy chronic cigarette smoking did not accelerate the pace of immunosenescence as compared with the Healthy aged.

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Background: The desaturation-distance ratio (DDR), the ratio of the desaturation area to the distance walked, is a promising, reliable, and simple physiologic tool for functional evaluation in subjects with interstitial lung diseases. Lymphangioleiomyomatosis (LAM) is a rare neoplastic condition frequently associated with exercise impairment. However, DDR has rarely been evaluated in patients with LAM. Objectives: To assess DDR during maximal and submaximal exercises and evaluate whether DDR can be predicted using lung function parameters. Methods: A cross-sectional study was conducted in a cohort of women with LAM. The 6-min walking test (6MWT) and the incremental shuttle walking test (ISWT) were performed, and DDR was obtained from both tests. The functional parameters were assessed at rest using spirometry and body plethysmography. The pulmonary function variables predictive of DDR were also assessed. Results: Forty patients were included in this study. The mean age was 46 ± 10 years. Airway obstruction, reduced DLCO, and air trapping were found in 60, 57, and 15% of patients, respectively. The distance walked and the DDR for the 6MWT and ISWT were, respectively, 517 ± 65 and 443 ± 127 m; and 6.6 (3.8-10.9) and 8.3 (6.2-12.7). FEV1 (airway obstruction) and reduced DLCO and RV/TLC (air trapping) were independent variables predictive of DDR during exercises field tests [DDR6MWT = 18.66-(0.06 × FEV1%pred)-(0.10 × DLCO%pred) + (1.54 × air trapping), R adjust 2 = 0.43] and maximal [DDRISWT = 18.84-(0.09 × FEV1%pred)-(0.05 × DLCO%pred) + (3.10 × air trapping), R adjust 2 = 0.33]. Conclusion: Our results demonstrated that DDR is a useful tool for functional evaluation during maximal and submaximal exercises in patients with LAM, and it can be predicted using airway obstruction, reduced DLCO, and air trapping.

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BACKGROUND AND AIMS: Dioecy has evolved up to 5000 times in angiosperms, despite the potentially high intrinsic costs to unisexuality. Dioecy prevents inbreeding, which is especially relevant on isolated islands when gene pools are small. Dioecy is also associated with certain dispersal traits, such as fruit size and type. However, the influence of dioecy on other life history traits and island distribution remains poorly understood. Here, we test the effect of dioecy on palm (Arecaceae) speciation rates, fruit size and frequency on islands. METHODS: We used phylogenetic comparative methods to estimate the ancestral state of the sexual system and its impact on speciation rates and fruit size. Frequency of sexual systems, effect of insularity on the probability of being dioecious, and phylogenetic clustering of island dioecious vs. mainland species were inferred. Lastly, we determined the interplay of insularity and sexual system on speciation rates. KEY RESULTS: Palms repeatedly evolved different sexual systems (dioecy, monoecy and polygamy) from a hermaphrodite origin. Differences in speciation rates and fruit size among the different sexual systems were not identified. An effect of islands on the probability of the palms being dioecious was also not found. However, we found a high frequency and phylogenetic clustering of dioecious palms on islands, which were not correlated with higher speciation rates. CONCLUSIONS: The high frequency and phylogenetic clustering may be the result of in situ radiation and suggest an 'island effect' for dioecious palms, which was not explained by differential speciation rates. This island effect also cannot be attributed to long-distance dispersal due to the lack of fruit size difference among sexual systems, and particularly because palm dispersal to islands is highly constrained by the interaction between the sizes of fruit and frugivores. Taken together, we suggest that trait flexibility in sexual system evolution and the in situ radiation of dioecious lineages are the underlying causes of the outstanding distribution of palms on islands.

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Immunosenescence are alterations on immune system that occurs throughout an individual life. The main characteristic of this process is replicative senescence, evaluated by telomere shortening. Several factors implicate on telomere shortening, such as smoking. In this study, we evaluated the influence of smoking and Chronic Obstructive Pulmonary Disease (COPD) on cytokines, telomere length and telomerase activity. Blood samples were collected from subjects aged over 60 years old: Healthy (never smokers), Smokers (smoking for over 30 years) and COPDs (ex-smokers for ≥15 years). A young group was included as control. PBMCs were cultured for assessment of telomerase activity using RT-PCR, and cytokines secretion flow cytometry. CD4+ and CD8+ purified lymphocytes were used to assess telomere length using FlowFISH. We observed that COPD patients have accelerated telomere shortening. Paradoxically, smokers without lung damage showed preserved telomere length, suggesting that tobacco smoking may affect regulatory mechanisms, such as telomerase. Telomerase activity showed diminished activity in COPDs, while Smokers showed increased activity compared to COPDs and Healthy groups. Extracellular environment reflected this unbalance, indicated by an anti-inflammatory profile in Smokers, while COPDs showed an inflammatory prone profile. Further studies focusing on telomeric maintenance may unveil mechanisms that are associated with cancer under long-term smoking.

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