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Bothrops envenomation is a public health problem in Brazil. Despite the advances in the knowledge of the pathogenesis of systemic and local effects induced by Bothrops venom, the target tissues to this venom are not completely characterised. As preadipocytes are important cells of the adipose tissue and synthesize inflammatory mediators, we investigated the ability of B. moojeni snake venom (Bmv) to stimulate an inflammatory response in 3T3-L1 preadipocytes in vitro, focusing on (1) the release of PGE2, IL-6, TNF-α, MCP-1, KC, leptin and adiponectin; (2) the mechanisms involved in PGE2 release and (3) differentiation of these cells. Cytotoxicity of Bmv was determined by MTT assay. The concentrations of PGE2, cytokines and adipokines were quantified by EIA. Participation of the COX-1 and COX-2 enzymes, NF-κB and PGE2 receptors (EP1-4) was assessed using a pharmacological approach, and protein expression of the COX enzymes and P-NF-κB was analysed by western blotting. Preadipocyte differentiation was quantified by Oil Red O staining. Bmv (1 μg/mL) induced release of PGE2, IL-6 and KC and increased expression of COX-2 in preadipocytes. Basal levels of TNF-α, MCP-1, leptin and adiponectin were not modified. Treatment of cells with SC560 (COX-1 inhibitor) and NS398 (COX-2 inhibitor) inhibited Bmv-induced PGE2 release. Bmv induced phosphorylation of NF-κB, and treatment of the cells with TPCK and SN50, which inhibit distinct NF-κB domains, significantly reduced Bmv-induced PGE2 release, as did the treatment with an antagonist of PGE2 receptor EP1, unlike treatment with antagonists of EP2, EP3 or EP4. Bmv also induced lipid accumulation in differentiating cells. These results demonstrate that Bmv can activate an inflammatory response in preadipocytes by inducing the release of inflammatory mediators; that PGE2 production is mediated by the COX-1, COX-2 and NF-κB pathways; and that engagement of EP1 potentiates PGE2 synthesis via a positive feedback mechanism. Our findings highlight the role of the adipose tissue as another target for Bmv and suggest that it contributes to Bothrops envenomation by producing inflammatory mediators.

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COVID-19 has caused radical effects on the daily lives of millions of people. The causal agent of the current pandemic is SARS-CoV-2, a virus that causes symptoms related to the respiratory system, leading to severe complications. In the in vitro fertilization (IVF) universe, there are several protocols for infection control and laboratory safety. Some professional associations have issued guidelines recommending measures involving patient flow and IVF practices. This study presents a review and considerations for the resumption of activities in IVF laboratories and clinics in Brazil during the COVID-19 pandemic, according to the guidelines and statements from professional organizations and societies in reproductive medicine.

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Matrix metalloproteinases (MMPs) are proteolytic enzymes that have been associated with the pathogenesis of inflammatory diseases and obesity. Adipose tissue in turn is an active endocrine organ capable of secreting a range of proinflammatory mediators with autocrine and paracrine properties, which contribute to the inflammation of adipose tissue and adjacent tissues. However, the potential inflammatory effects of MMPs in adipose tissue cells are still unknown. This study investigates the effects of BmooMPα-I, a single-domain snake venom metalloproteinase (SVMP), in activating an inflammatory response by 3T3-L1 preadipocytes in culture, focusing on prostaglandins (PGs), cytokines, and adipocytokines biosynthesis and mechanisms involved in prostaglandin E2 (PGE2) release. The results show that BmooMPα-I induced the release of PGE2, prostaglandin I2 (PGI2), monocyte chemoattractant protein-1 (MCP-1), and adiponectin by preadipocytes. BmooMPα-I-induced PGE2 biosynthesis was dependent on group-IIA-secreted phospholipase A2 (sPLA2-IIA), cytosolic phospholipase A2-α (cPLA2-α), and cyclooxygenase (COX)-1 and -2 pathways. Moreover, BmooMPα-I upregulated COX-2 protein expression but not microsomal prostaglandin E synthase-1 (mPGES-1) expression. In addition, we demonstrate that the enzymatic activity of BmooMPα-I is essential for the activation of prostanoid synthesis pathways in preadipocytes. These data highlight preadipocytes as important targets for metalloproteinases and provide new insights into the contribution of these enzymes to the inflammation of adipose tissue and tissues adjacent to it.

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Adipose tissue secretes proinflammatory mediators which promote systemic and adipose tissue inflammation seen in obesity. Group IIA (GIIA)-secreted phospholipase A2 (sPLA2) enzymes are found to be elevated in plasma and adipose tissue from obese patients and are active during inflammation, generating proinflammatory mediators, including prostaglandin E2 (PGE2). PGE2 exerts anti-lipolytic actions and increases triacylglycerol levels in adipose tissue. However, the inflammatory actions of GIIA sPLA2s in adipose tissue cells and mechanisms leading to increased PGE2 levels in these cells are unclear. This study investigates the ability of a representative GIIA sPLA2, MT-III, to activate proinflammatory responses in preadipocytes, focusing on the biosynthesis of prostaglandins, adipocytokines and mechanisms involved in these effects. Our results showed that MT-III induced biosynthesis of PGE2, PGI2, MCP-1, IL-6 and gene expression of leptin and adiponectin in preadipocytes. The MT-III-induced PGE2 biosynthesis was dependent on cytosolic PLA2 (cPLA2)-α, cyclooxygenases (COX)-1 and COX-2 pathways and regulated by a positive loop via the EP4 receptor. Moreover, MT-III upregulated COX-2 and microsomal prostaglandin synthase (mPGES)-1 protein expression. MCP-1 biosynthesis induced by MT-III was dependent on the EP4 receptor, while IL-6 biosynthesis was dependent on EP3 receptor engagement by PGE2. These data highlight preadipocytes as targets for GIIA sPLA2s and provide insight into the roles played by this group of sPLA2s in obesity.

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Adipose tissue secretes proinflammatory mediators which promote systemic and adipose tissue inflammation seen in obesity. Group IIA (GIIA)-secreted phospholipase A2 (sPLA2) enzymes are found to be elevated in plasma and adipose tissue from obese patients and are active during inflammation, generating proinflammatory mediators, including prostaglandin E2 (PGE2). PGE2 exerts anti-lipolytic actions and increases triacylglycerol levels in adipose tissue. However, the inflammatory actions of GIIA sPLA2s in adipose tissue cells and mechanisms leading to increased PGE2 levels in these cells are unclear. This study investigates the ability of a representative GIIA sPLA2, MT-III, to activate proinflammatory responses in preadipocytes, focusing on the biosynthesis of prostaglandins, adipocytokines and mechanisms involved in these effects. Our results showed that MT-III induced biosynthesis of PGE2, PGI2, MCP-1, IL-6 and gene expression of leptin and adiponectin in preadipocytes. The MT-III-induced PGE2 biosynthesis was dependent on cytosolic PLA2 (cPLA2)-α, cyclooxygenases (COX)-1 and COX-2 pathways and regulated by a positive loop via the EP4 receptor. Moreover, MT-III upregulated COX-2 and microsomal prostaglandin synthase (mPGES)-1 protein expression. MCP-1 biosynthesis induced by MT-III was dependent on the EP4 receptor, while IL-6 biosynthesis was dependent on EP3 receptor engagement by PGE2. These data highlight preadipocytes as targets for GIIA sPLA2s and provide insight into the roles played by this group of sPLA2s in obesity.

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Palladacycle complex DPPE 1.2 was previously reported to inhibit the in vitro and in vivo infection by Leishmania (Leishmania) amazonensis. The aim of the present study was to compare the effect of DPPE 1.2, in association with heat-killed Propionibacterium acnes, on L. (L.) amazonensis infection in two mouse strains, BALB/c and C57BL/6, and to evaluate the immune responses of the treated animals. Foot lesions of L. (L.) amazonensis-infected mice were injected with DPPE 1.2 alone, or associated with P. acnes as an adjuvant. Analysis of T-cell populations in the treated mice and in untreated controls was performed by FACS. Detection of IFN-γ-secreting lymphocytes was carried out by an ELISPOT assay and active TGF-ß was measured by means of a double-sandwich ELISA test. The treatment with DPPE 1.2 resulted in a significant reduction of foot lesion sizes and parasite burdens in both mouse strains, and the lowest parasite burden was found in mice treated with DPPE 1.2 plus P. acnes. Mice treated with DPPE 1.2 alone displayed a significant increase of TCD4+ and TCD8+ lymphocytes and IFN-γ secretion which were significantly higher in animals treated with DPPE 1.2 plus P. acnes. A significant reduction of active TGF-ß was observed in mice treated with DPPE 1.2 alone or associated with P. acnes. Moreover, DPPE 1.2 associated to P. acnes was non-toxic to treated animals. The destruction of L. (L.) amazonensis by DPPE 1.2 was followed by host inflammatory responses which were exacerbated when the palladacycle complex was associated with P. acnes.

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BACKGROUND: Influenza affects thousands of people worldwide every year, motivating the development of new therapies. In this work, the effects of two homeopathic preparations (influenza biotherapies and thymulin) were chosen following two different rationales: isotherapy and endo-isotherapy models. The homeopathic effects were evaluated individually considering the inflammatory and behavioral responses against influenza virus antigen were studied in BALB/c mice. METHODS: Male adult mice were treated orally and blindly for 21 days with highly diluted influenza virus or with thymulin, and were divided in two sets of experiments. The first series of experiments aimed to describe their behavior, using an open field (OF) device. In the second series, mice were challenged subcutaneously with influenza hemagglutinin antigen (7 µg/200 µl) at day 21. At day 42, behavior and inflammation response were evaluated. RESULTS: No behavioral changes were seen in OF tests at any time point after treatments. Flow cytometry and morphometry revealed significant changes in T and B cell balance after influenza antigen challenge, varying according to treatment. CONCLUSION: The results show that both homeopathic treatments induced subtle changes in acquired immune anti-viral response regulation. A deeper understanding of the mechanism could elucidate their possible use in influenza epidemiological situations.

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Diante da constante mudança do processo de produção ao longo dos séculos e da consequente mudança do perfil epidemiológico na população trabalhadora, pesquisas atualizadas sobre a saúde do trabalhador e sobre acidentes de trabalho tornam-se importantes. No Brasil, na década de 1990, o setor terciário ganhou espaço e modificou a estrutura de empregos no País. Dado o aumento dos postos de trabalho nesse setor, principalmente nas capitais brasileiras, é necessário verificar em quais aspectos a atual organização de emprego está interferindo na morbimortalidade dos trabalhadores. Desse modo, objetiva-se com este estudo descrever os acidentes de trabalho ocorridos no setor de atividade Comércio, buscando sua caracterização epidemiológica, no município de Belo Horizonte, no período de 2004 a 2008. Os dados foram coletados no Sistema de Informação sobre Acidente de Trabalho (SIAT/SUS) da Gerência de Saúde do Trabalhador da Secretaria Municipal de Saúde. A amostra foi composta de 6.942 acidentes, sendo os homens os mais acometidos (81,1%) e a faixa etária de 20 a 29 anos a mais expressiva (62,6%). O acidente típico foi o mais comum (84,1%) e a ocupação repositor de mercadorias (10,8%) a mais representativa. A maioria dos acidentes aconteceu no distrito sanitário Centro-Sul (30,5%) e o Hospital João XXIII foi a Unidade de Saúde que mais atendeu os acidentados (66,8%). A causa mais comum foi queda/ choque/ perda de equilíbrio (22,1%). Com base nesses dados, tornou-se possível subsidiar a construção de medidas de prevenção e políticas públicas específicas para os trabalhadores do setor.

Considering the changes in the production process and in the epidemiological profile of the working population over the centuries, it became necessary an updated research on workers' health and on accidents at work. During the 90's Brazil's tertiary sector growth changed the country's employment structure. The increase in the sector's employment offer, especially in the Brazilian state capitals, made it necessary to identify current employment characteristics that influence the morbidity among workers. This study aims to describe work-related accidents occurred in the commercial sector in the city of Belo Horizonte, and to identify its epidemiological characteristics in the period between 2004 and 2008. Data were collected from the Information System on Occupational Accidents (in Portuguese, SIAT / SUS) of the Occupational Health Administration of the Municipal Health Department. The sample consisted of 6942 work accidents in which 62.6% men, aged 20 to 29 years old (81.1%), were the most affected.The typical accident was the most frequent (84.1%) and the replenishment position (10.8%) the most representative. Most accidents happened in the south centre health district (30.5%) and John XXIII Hospital attended most cases (66.8%). The most common cause of work related accidents were falls, electrical incidents, trips or slips (22.1%). The study's findings helped to promote the establishment of a series of preventive measures and public policies specific for people working in that economic sector.

Ante el cambio constante con los siglos en el proceso de producción y del consiguiente cambio de perfil epidemiológico en la población de trabajadores, las investigaciones actualizadas sobre la salud del trabajador y sobre los accidentes de trabajo son sumamente importantes. En el Brasil de los años 90, el sector terciario adquirió espacio y modificó la estructura de los empleos en el país. Debido al aumento de tales puestos de trabajo en ese sector, principalmente en las capitales, hay que verificar en qué aspectos la organización actual de empleo interfiere en la morbimortalidad de los trabajadores. Con el presente estudio se busca describir los accidentes de trabajo ocurridos en el rubro Comercio, intentando definir su epidemiología en el municipio de Belo Horizonte entre 2004 y 2008. Los datos fueron recogidos en el Sistema de Información sobre Accidentes de Trabajo (SIAT/SUS) del Departamento de Salud del Trabajador de la Secretaría Municipal de Salud. La muestra consistió en 6.942 accidentes de los cuales los hombres fueron los más perjudicados (81,1%) y entre 20 y 29 años (62,6%) la mayoría. El accidente típico fue el más común (84,1%) y la ocupación repositor de mercaderías (10,8%) la más representativa. La mayoría de los accidentes ocurrió en el distrito sanitario Centro Sur (30,5%) y el Hospital João XXIII fue el centro de salud que atendió más accidentados (66,8%). La causa más común fue caída/choque/pérdida de equilibrio (22,1%). Los resultados de este estudio han contribuido a elaborar medidas de prevención y políticas públicas específicas para los trabajadores del sector.

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