A nasal airway-on-chip model to evaluate airflow pre-conditioning during epithelial cell maturation at the air-liquid interface.

The function of a well-differentiated nasal epithelium is largely affected by airflow-induced wall shear stress, yet fewin vitromodels recapitulate this dynamic condition. Models which do expose cells to airflow exclusively initiate flow after the differentiation process has occurred.In vivo, basal cells are constantly replenishing the epithelium under airflow conditions, indicating that airflow may affect the development and function of the differentiated epithelium. To address this gap in the field, we developed a physiologically relevant microphysiological model of the human nasal epithelium and investigated the effects of exposing cells to airflow during epithelial maturation at the air-liquid interface. The nasal airway-on-chip platform was engineered to mimic bi-directional physiological airflow during normal breathing. Primary human nasal epithelial cells were seeded on chips and subjected to either: (1) no flow, (2) single flow (0.5 dyne cm-2flow on Day 21 of ALI only), or (3) pre-conditioning flow (0.05 dyne cm-2on Days 14-20 and 0.5 dyne cm-2flow on Day 21) treatments. Cells exposed to pre-conditioning showed decreased morphological changes and mucus secretions, as well as decreased inflammation, compared to unconditioned cells. Our results indicate that flow exposure only post-differentiation may impose acute stress on cells, while pre-conditioning may potentiate a properly functioning epitheliumin vitro.

Improving access to cancer clinical research in Brazil: recent advances and new opportunities. Expert opinions from the 4th CURA meeting, São Paulo, 2023.

Clinical research is the cornerstone of improvements in cancer care. However, it has been conducted predominantly in high-income countries with few clinical trials available in Brazil and other low-and-middle-income countries (LMIC). Of note, less than one-third of registered clinical trials addressing some of the most commonly diagnosed cancers (breast, lung and cervical) recruited patients from LMIC in the last years. The Institute Project CURA promoted the fourth CURA meeting, discussing barriers to cancer clinical research and proposing potential solutions. A meeting was held in São Paulo, Brazil, in June 2023 with representatives from different sectors: Brazilian Health Regulatory Agency (Anvisa), National Commission of Ethics in Research (CONEP), non-governmental organisations, such as the Latin American Cooperative Oncology Group, the Brazilian Society of Clinical Oncology (SBOC), Contract Research Organisations, pharmaceutical companies and investigators. A total of 16 experts pointed out achievements as shortening the time of regulatory processes involving Anvisa and CONEP, development of staff training programs, maintenance of the National Program of Oncological Attention (PRONON), and the foundation of qualified centres in North and Northeast Brazilian regions. Participants also highlighted the need to be more competitive in the field, which requires optimising ongoing policies and implementing new strategies as decentralisation of clinical research centres, public awareness campaigns, community-centered approaches, collaborations and partnerships, expansion of physicians-directed policies, exploring the role of the steering committee. Active and consistent reporting of the initiatives might help to propagate ongoing advances, increasing Brazilian participation in clinical cancer research. Engagement of all players is crucial to maintain continuous progress with further improvements in critical points including regulatory timelines and increments in qualified human resources which aligned with new educational initiatives focused on physicians and the general population will expand access to cancer clinical trials in Brazil.

Hypothalamic inflammation and the development of an obese phenotype induced by high-fat diet consumption is exacerbated in alpha7 nicotinic cholinergic receptor knockout mice.

Hypothalamic inflammation and metabolic changes resulting from the consumption of high-fat diets have been linked to low grade inflammation and obesity. Inflammation impairs the hypothalamic expression of α7 nicotinic acetylcholine receptor (α7nAChR). The α7nAChR is described as the main component of the anti-inflammatory cholinergic pathway in different inflammation models. To assess whether the reduction in α7nAChR expression exacerbates hypothalamic inflammation induced by a high-fat diet (HFD), were used male and female global α7nAChR knockout mouse line in normal or high-fat diet for 4 weeks. Body weight gain, adiposity, glucose homeostasis, hypothalamic inflammation, food intake, and energy expenditure were evaluated. Insulin sensitivity was evaluated in neuronal cell culture. Consumption of an HFD for 4 weeks resulted in body weight gain and adiposity in male Chrna7-/- mice and the hypothalamus of male Chrna7-/- mice showed neuroinflammatory markers, with increased gene expression of pro-inflammatory cytokines and dysregulation in the nuclear factor kappa B pathway. Moreover, male Chrna7-/- mice consuming an HFD showed alterations in glucose homeostasis and serum of Chrna7-/- mice that consumed an HFD impaired insulin signalling in neuronal cell culture experiments. In general, female Chrna7-/- mice that consumed an HFD did not show the phenotypic and molecular changes found in male mice, indicating that there is sexual dimorphism in the analysed parameters. Thus, receptor deletion resulted in increased susceptibility to hypothalamic inflammation and metabolic damage associated with HFD consumption in male mice.

Blimp-1 signaling pathways in T lymphocytes is essential to control the Trypanosoma cruzi infection-induced inflammation.

In many infectious diseases, the pathogen-induced inflammatory response could result in protective immunity that should be regulated to prevent tissue damage and death. In fact, in Trypanosoma cruzi infection, the innate immune and the inflammatory response should be perfectly controlled to avoid significant lesions and death. Here, we investigate the role of Blimp-1 expression in T cells in resistance to T. cruzi infection. Therefore, using mice with Blimp-1 deficiency in T cells (CKO) we determined its role in the controlling parasites growth and lesions during the acute phase of infection. Infection of mice with Blimp-1 ablation in T cells resulted failure the cytotoxic CD8+ T cells and in marked Th1-mediated inflammation, high IFN-γ and TNF production, and activation of inflammatory monocyte. Interestingly, despite high nitric-oxide synthase activation (NOS-2), parasitemia and mortality in CKO mice were increased compared with infected WT mice. Furthermore, infected-CKO mice exhibited hepatic lesions characteristic of steatosis, with significant AST and ALT activity. Mechanistically, Blimp-1 signaling in T cells induces cytotoxic CD8+ T cell activation and restricts parasite replication. In contrast, Blimp-1 represses the Th1 response, leading to a decreased monocyte activation, less NOS-2 activation, and, consequently preventing hepatic damage and dysfunction. These data demonstrate that T. cruzi-induced disease is multifactorial and that the increased IFN-γ, NO production, and dysfunction of CD8+ T cells contribute to host death. These findings have important implications for the design of potential vaccines against Chagas disease.

Hypothalamic α7 nicotinic acetylcholine receptor (α7nAChR) is downregulated by TNFα-induced Let-7 overexpression driven by fatty acids.

The α7nAChR is crucial to the anti-inflammatory reflex, and to the expression of neuropeptides that control food intake, but its expression can be decreased by environmental factors. We aimed to investigate whether microRNA modulation could be an underlying mechanism in the α7nAchR downregulation in mouse hypothalamus following a short-term exposure to an obesogenic diet. Bioinformatic analysis revealed Let-7 microRNAs as candidates to regulate Chrna7, which was confirmed by the luciferase assay. Mice exposed to an obesogenic diet for 3 days had increased Let-7a and decreased α7nAChR levels, accompanied by hypothalamic fatty acids and TNFα content. Hypothalamic neuronal cells exposed to fatty acids presented higher Let-7a and TNFα levels and lower Chrna7 expression, but when the cells were pre-treated with TLR4 inhibitor, Let-7a, TNFα, and Chrna7 were rescued to normal levels. Thus, the fatty acids overload trigger TNFα-induced Let-7 overexpression in hypothalamic neuronal cells, which negatively regulates α7nAChR, an event that can be related to hyperphagia and obesity predisposition in mice.

Assessing color cues of development, breeding status and reproductive condition in captive golden lion tamarins (Leontopithecus rosalia).

Color signals play an important role in intraspecific communication and are well studied in catarrhine primates, which exhibit uniform trichromatic vision that is well suited to detecting such signals. Platyrrhine primates exhibit polymorphic color vision with different individuals possessing different color vision types in most species. Intriguingly, some platyrrhine species exhibit bare faces, which are convergent with those of catarrhines. However, putative functions of bare-faced color signals in platyrrhines remain largely unexplored. We measured facial skin color of five captive golden lion tamarins (Leontopithecus rosalia) using color-calibrated digital photography and modeled these colors to the visual systems of the species. Our results show that facial coloration is different between infant and older adults and varies across reproductive condition, but not between breeding and nonbreeding adults. While preliminary, our study suggests that facial coloration may be involved in sociosexual signaling in golden lion tamarins, and provides intriguing evidence that we hope might stimulate more studies of bare-faced signaling in platyrrhines.

NKG2D promotes CD8 T cell-mediated cytotoxicity and is associated with treatment failure in human cutaneous leishmaniasis.

Cutaneous leishmaniasis exhibits a spectrum of clinical presentations dependent upon the parasites' persistence and host immunopathologic responses. Although cytolytic CD8 T cells cannot control the parasites, they significantly contribute to pathologic responses. In a murine model of cutaneous leishmaniasis, we previously found that NKG2D plays a role in the ability of cytolytic CD8 T cells to promote disease in leishmanial lesions. Here, we investigated whether NKG2D plays a role in human disease. We found that NKG2D and its ligands were expressed within lesions from L. braziliensis-infected patients and that IL-15 and IL-1ß were factors driving NKG2D and NKG2D ligand expression, respectively. Blocking NKG2D reduced degranulation by CD8 T cells in a subset of patients. Additionally, our transcriptional analysis of patients' lesions found that patients who failed the first round of treatment exhibited higher expression of KLRK1, the gene coding for NKG2D, than those who responded to treatment. These findings suggest that NKG2D may be a promising therapeutic target for ameliorating disease severity in cutaneous leishmaniasis caused by L. braziliensis infection.

A decade of Zoology Summer Course: impressions and impacts of the first university extension course on Zoology in Brazil / Uma década de Curso de Verão em Zoologia: impressões e impactos do primeiro curso de extensão universitária sobre Zoologia no Brasil

Although the diversity of animal groups distributed in Brazil provides countless research opportunities, the current scenario does not follow this demand. The reasons for the disconnections range from inequality in the availability of resources for teaching and research to the focus of researchers on specific groups of animals, while others remain neglected. Training new potential Brazilian researchers interested in Zoology is essential for a greater understanding of this diversity, as well as exposing those potential new researchers to new groups and different work possibilities. Thus, the Summer Course in Zoology (in Portuguese, CVZoo) promoted by the Graduate Program in Zoology at the University of São Paulo, over the last ten years, has been seeking to contribute to this training of new researchers in the field of Zoology, as well as in updating teachers through university extension activities. In order to assess the impacts caused by CVZoo on the academic and professional training of the participants, Google forms were sent to participants in the ten editions of the course, as well as compiled information available on the Lattes Platform. Qualitative and quantitative analyses showed the profile of graduates, their expectations, and perceptions about the course. Based on these data, we demonstrate the CVZoo's efficiency in popularizing Zoology throughout the country in contributing to the decentralization of knowledge as well as in meeting the urgent concerns of making access to knowledge more egalitarian and socially fair.

Embora a diversidade de grupos de animais existentes no Brasil ofereça inúmeras oportunidades de estudo, o cenário atual não acompanha essa demanda. Os motivos para essa desconexão vão desde a desigualdade na disponibilidade de recursos para ensino e pesquisa até o foco de pesquisadores em grupos específicos de animais, enquanto outros permanecem negligenciados. O treinamento de novos pesquisadores interessados em Zoologia é essencial para um maior entendimento da diversidade brasileira, assim como a exposição de tais pesquisadores a novos grupos e diferentes possibilidades de trabalho. O Curso de Verão em Zoologia (CVZoo) promovido pelo Programa de Pós-graduação em Zoologia da Universidade de São Paulo, ao longo de dez anos vem buscando contribuir para a formação de novos(as) pesquisadores(as) na área da Zoologia, bem como na atualização de docentes do Ensino Básico por meio de atividades de extensão universitária. Para avaliar os impactos causados pelo CVZoo na formação acadêmica e profissionalizante dos participantes, foram enviados formulários aos participantes das dez edições do curso, bem como compiladas informações disponíveis na Plataforma Lattes. Análises qualitativas e quantitativas evidenciaram o perfil das pessoas egressas, suas expectativas e percepções acerca do curso oferecido. Com base nesses dados, é apontada a eficiência do CVZoo na popularização da Zoologia por todo o país, contribuindo para a descentralização do conhecimento, bem como atendendo às preocupações prementes de tornar o acesso ao conhecimento mais igualitário e socialmente justo

Genetic basis of sleep phenotypes and rare neurodevelopmental syndromes reveal shared molecular pathways.

Sleep-related phenotypes have been frequently reported in early on-set epileptic encephalopathies and in developmental delay syndromes, in particular in syndromes related to autism spectrum disorder. Yet the convergent pathogenetic mechanisms between these comorbidities are largely unknown. We first performed a gene enrichment study that identified shared risk genes among rare epileptic encephalopathies/neurodevelopmental disorders, rare developmental delay genetic syndromes and sleep disturbances. We then determined cellular and molecular pathways enriched among genes shared between sleep phenotypes and those two early onset mental illnesses, aiming to identify genetic disparities and commonalities among these phenotypic groups. The sleep gene set was observed as significantly overlapped with the two gene lists associated to rare genetic syndromes (i.e., epileptic encephalopathies/neurodevelopmental disorders and developmental delay gene sets), suggesting shared genetic contribution. Similarities across significantly enriched pathways between the two intersect lists comprehended mostly synapse-related pathways, such as retrograde endocannabinoid signaling, serotonergic, and GABAergic synapse. Network analysis indicates epileptic encephalopathies/neurodevelopmental disorders versus sleep-specific clusters and developmental delay versus sleep-specific clusters related to synaptic and transcriptional regulation, respectively. Longstanding functional patterns previously described in epileptic encephalopathies and neurodevelopmental disorders genetic architecture were recaptured after dissecting the overlap between the genes associated to those developmental phenotypes and sleep disturbances, suggesting that during neurodevelopment different molecular and functional mechanisms are related to alterations on circadian rhythm. The overlapping gene set and biological pathways highlighted by this study may serve as a primer for new functional investigations of shared molecular mechanisms between sleep disturbances and rare developmental syndromes.

Fate and Trophic Transfer of Rare Earth Elements in a Tropical Estuarine Food Web.

We sampled abiotic and food web components in an impacted estuarine system to assess the transfer and fate of rare earth elements (REE). REE (based on dry weight) were measured in sediments, suspended particulate matter (SPM), and organisms from different trophic levels. The highest ∑REE concentrations were measured in sediments (180 ± 4.24 mg kg-1) and SPM (163 ± 12.6 mg kg-1). Phytoplankton (45.7 ± 5.31 mg kg-1), periphyton (51.6 ± 1.81 mg kg-1), and zooplankton (68.5 ± 1.27 mg kg-1) are the major sources of exposure and transfer of REE to the food web. REE concentrations were several orders of magnitude lower in bivalves, crustaceans, and fish (6.01 ± 0.11, 1.22 ± 0.18, and 0.059 ± 0.003 mg kg-1, respectively) than in plankton. The ∑REE declined as a function of the trophic position, as determined by functional feeding groups and δ15N, indicating that REE were subject to trophic dilution. Our study suggests that the consumption of seafood is unlikely to be an important source of REE for humans. However, given the numerous sources of dietary introduction of REE, they should be monitored for a possible harmful cumulative effect. This study provides new key information on REE's baseline concentrations and trophic transfers and patterns.