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The emergence and widespread circulation of severe acute respiratory syndrome coronavirus 2 variants of concern (VOCs) or interest impose an enhanced threat to global public health. In Brazil, one of the countries most severely impacted throughout the pandemic, a complex dynamics involving variants co-circulation and turnover events has been recorded with the emergence and spread of VOC Gamma in Manaus in late 2020. In this context, we present a genomic epidemiology investigation based on samples collected between December 2020 and May 2021 in the second major Brazilian metropolis, Rio de Janeiro. By sequencing 244 novel genomes through all epidemiological weeks in this period, we were able to document the introduction and rapid dissemination of VOC Gamma in the city, driving the rise of the third local epidemic wave. Molecular clock analysis indicates that this variant has circulated locally since the first weeks of 2021 and only 7 weeks were necessary for it to achieve a frequency above 70 per cent, consistent with rates of growth observed in Manaus and other states. Moreover, a Bayesian phylogeographic reconstruction indicates that VOC Gamma spread throughout Brazil between December 2020 and January 2021 and that it was introduced in Rio de Janeiro through at least 13 events coming from nearly all regions of the country. Comparative analysis of reverse transcription-quantitative polymerase chain reaction (RT-qPCR) cycle threshold (Ct) values provides further evidence that VOC Gamma induces higher viral loads (N1 target; mean reduction of Ct: 2.7, 95 per cent confidence interval = ± 0.7). This analysis corroborates the previously proposed mechanistic basis for this variant-enhanced transmissibility and distinguished epidemiological behavior. Our results document the evolution of VOC Gamma and provide independent assessment of scenarios previously studied in Manaus, therefore contributing to the better understanding of the epidemiological dynamics currently being surveyed in other Brazilian regions.

Background: Cutaneous melanoma is a highly malignant tumor derived from pigment-producing (melanin) melanocytes of skin epidermis. Cutaneous pigmentation is described as the major physiologic defense against UV radiation. During melanin biosynthesis and other tumorigenic process, reactive oxygen species (ROS) are produced and might be critically involved in several melanomagenesis stages. ROS play key roles on regulation of many types cell proliferation, including melanoma cells. Aims: In this work we evaluated the effects of highly diluted compounds on melanogenesis and changes in reactive oxygen species after 96 hours of treatment and possible involvement in tumorigenesis. Methodology: Melanin content was measured in B16-F10 cells after 96 hours of treatment with highly diluted compounds, as well as the superoxide anion, hydrogen peroxide and nitric oxide. Furthermore, the effects of highly diluted compounds on cell proliferation were investigated by trypan blue exclusion method after 48 hours of treatment. Results: Treatment led to an increase in B16-F10 melanin content and a decrease in nitrite concentration, an intermediate product of nitric oxide. We also observed a decrease in cell proliferation after treatment. It is well recognized that nitric oxide (NO) is involved in tumor progression, including melanoma. Several articles show that NO treated B16-F10 cells exhibited higher metastatic capacity. Thereby, reduction in cell proliferation can be due to low NO levels. It is speculated that melanocytes are programmed to survive in order to preserve their photoprotective role, thus in a compensatory manner the cell may be synthesizing melanin in response to cell proliferation reduction. Conclusions: These results suggest that treatment may be reducing tumorigenic capacity via ROS reduction. However further studies are need to better understand highly diluted compounds mechanisms of action.

Metastasis is responsible for the majority of deaths among patients with malignant melanoma. Despite recent advances, the majority of current and modern therapies are ineffective and/or financially unfeasible. Thus, in this study, we investigated two low‑cost highly‑diluted natural complexes (HDNCs) that have been shown to be effective against malignant melanoma in a murine model in vivo. The aim of this study was to determine the mechanisms through which these HDNCs directly affect melanoma cells, either alone or in an artificial tumor microenvironment, suppressing the metastatic phenotype, thus explaining previous in vivo effects. For this purpose, HDNC in vitro treatments of B16‑F10 melanoma cells, alone or in co‑culture with Balb/3T3 fibroblasts, were carried out. Molecular biology techniques and standard functional assays were used to assess the changes in molecule expression and in cell behaviors related to the metastatic phenotype. Melanoma progression features were found to be regulated by HDNCs. Molecules related to cell adhesion (N‑cadherin, β1‑integrin and CD44), and migration, extracellular matrix remodeling and angiogenesis were modulated. The cell migratory, invasive and clonogenic capacities were reduced by the HDNCs. No loss of cell proliferation or viability were observed. On the whole, the findings of this study indicate that HDNCs directly reprogram, molecularly and functionally, melanoma cells in vitro, modulating their metastatic phenotype. Such findings are likely to be responsible for the attenuation of tumor growth and lung colonization previously observed in vivo.

Several synthetic dyes are used by textile industry for supplying the market of colored clothes. However, these chemicals have been associated with a variety of adverse human health effects, including textile dermatitis. Thus, there is a growing concern to identify textile dyes potentially as skin immunotoxicants. The aim of this in vitro study was to characterize the immunotoxic potential of reactive (Reactive Green 19 [RG19], Reactive Blue 2 [RB2], Reactive Black 5 [RB5]) and disperse (Disperse Red 1 [DR1]) textile dyes using a dermal cell line. For this purpose, a cell-based approach was conducted with immortalized human keratinocytes (KC) (HaCaT) using selected biomarkers of cutaneous inflammation including modulation of matrix metalloproteinases (MMP), oxidative stress such as reactive oxygen species (ROS) generation, and inflammatory cytokine profile. DR1 was the only dye able to trigger an immune response such as release of IL-12 cytokine, a potent co-stimulator of T helper 1 cell, which may be considered as a skin immunotoxicant. The reactive dyes including RB5 that were previously reported as skin sensitizers failed to induce inflammatory reactions under the conditions tested. The reactive dyes studied may pose a risk to human KC by induction of effects related to modulation of MMP-2 (RB5) and -9 (RB5 and RB2) and generation of ROS (RG19 and RB2). Thus, all these dyes need to be used with caution to avoid undesirable effects to consumers who may be exposed dermally.

This manuscript describes the evaluation of anti-infective potential in vitro of organic extracts from nine sponges, one ascidian, two octocorals, one bryozoan, and 27 seaweed species collected along the Brazilian coast. Antimicrobial activity was tested against Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Escherichia coli (ATCC 25922) and Candida albicans (ATCC 10231) by the disk diffusion method. Antiprotozoal activity was evaluated against Leishmania braziliensis (MHOM/BR/96/LSC96-H3) promastigotes and Trypanosoma cruzi (MHOM/BR/00/Y) epimastigotes by MTT assay. Activity against intracellular amastigotes of T. cruzi and L. brasiliensis in murine macrophages was also evaluated. Antiviral activity was tested against Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the plaque number reduction assay (IC50). Cytotoxicity on VERO cells was evaluated by the MTT assay (CC50). The results were expressed as SI = CC50/IC50. The most promising antimicrobial results were obtained against S. aureus and C. albicans with Dragmacidon reticulatum. Among the seaweeds, only Osmundaria obtusiloba showed moderate activity against P. aeruginosa. Concerning antiprotozoal activity, Bugula neritina, Carijoa riseii, Dragmaxia anomala and Haliclona (Halichoclona) sp. showed the most interesting results, mainly against extracellular promastigote forms of L. braziliensis (66, 35.9, 97.2, and 43.6% inhibition, respectively). Moreover, six species of seaweeds Anadyomene saldanhae, Caulerpa cupressoides, Canistrocarpus cervicornis, Dictyota sp., Ochtodes secundiramea, and Padina sp. showed promising results against L. braziliensis (87.9, 51.7, 85.9, 93.3, 99.7, and 80.9% inhibition, respectively), and only Dictyota sp. was effective against T. cruzi (60.4% inhibition). Finally, the antiherpes activity was also evaluated, with Haliclona (Halichoclona) sp. and Petromica citrina showing the best results (SI = 11.9 and SI > 5, respectively). All the active extracts deserve special attention in further studies to chemically characterize the bioactive compounds, and to perform more refined biological assays.

Ethnopharmacological relevance Maytenus ilicifolia Mart. ex. Reissek (Celastraceae) is widely used in Brazilian folk medicine to treat gastric disturbances. Aim of the study This work intended to characterize the effects of Maytenus ilicifolia on gastrointestinal motility. Materials and methods Gastric emptying and intestinal transit were measured in the same animal. Mice received a semisolid marked with phenol red, half an hour after treatment with extracts. The amount of marker in the stomach and the distance reached in the intestine after 15 min were measured as index of gastrointestinal emptying and intestinal transit, respectively. Results Intraperitoneal administration of a flavonoid-rich extract potently reduced the gastric emptying (ED50 = 89 mg/kg) and the intestinal transit (ED50 = 31 mg/kg) of mice. Bio-guided purification of the flavonoid-rich extract by chemical partition with solvents of decreasing polarity yielded fraction insF with about 12–14 times higher activity than the initial flavonoid extract in both the gastric emptying and the intestinal transit. The inhibitory effects of the insF (9.7 mg/kg, i.p.) on gastric emptying and intestinal transit were reversed by co-administration of bethanechol (10 mg/kg, s.c.) but not by co-administration of metoclopramide (30 mg/kg, p.o.) indicating muscarinic but not dopaminergic interaction of the compounds of Maytenus. Chemical investigation of the insF fraction by HPLC–MS allowed the identification of 4 free flavonoids (catechin, epicatechin, quercetin and kaempferol), 29 flavonol glycosides and 8 tannins. The flavonol glycosides ranged from 1 to 4 monosaccharide units, having mainly quercetin and kaempferol as aglycone moieties, and the tannins were composed by catechin/epicatechin and/or afzelechin/epiafzelechin. Conclusions Overall, the results indicate that the components of Maytenus ilicifolia have a potential use in the treatment of gastrointestinal motility disturbances such as diarrhea.

Orientador : Prof. Dr. Edvaldo da Silva Trindade Co-orientadora : Profª. Drª. Carolina Camargo de Oliveira Tese (doutorado) - Universidade Federal do Paraná, Setor de Ciências Biológicas, Programa de Pós-Graduação em Biologia Celular e Molecular. Defesa: Curitiba, 24/02/2014 Inclui referências Área de concentração : Biologia celular molecular Resumo: O melanoma é um tipo de câncer de pele altamente metastático. Drogas quimioterápicas convencionais usadas atualmente possuem efeitos limitados, assim, terapias mais efetivas são necessárias. Este trabalho objetivou a investigação e elucidação de possíveis mudanças nas características das células de melanoma B16F10, desencadeadas pelo tratamento in vitro com os complexos naturais altamente diluídos (M1 ou M8). Para tanto, as células foram tratadas por 96 horas com M1 ou com M8 e diversos parâmetros foram analisados, enfocando possíveis alterações na expressão de mRNA de proteínas envolvidas na invasão, migração e proliferação celular; bem como avaliação de moléculas envolvidas em espécies reativas; na melanogênese e mecanismo de resistência a multidrogas. Por fim, avaliação em glicoconjugados foi realizada. Os resultados mostram claramente que o tratamento com M1 ou M8 reduz características metastáticas importantes, evidenciada, pela diminuição da expressão de metaloproteases (MT1-MMP, MMP-2 e MMP-9), e de sua atividade gelatinase; bem como da migração celular. Essa última, foi, possivelmente, decorrente do aumento de espécies reativas de oxigênio (ROS), liberação de óxido nítrico (NO) e redução de NO intracelular. Curiosamente esse efeito foi acompanhado pela redução na síntese de melanina e atividade e expressão da tirosinase (TYR), bem como da expressão gênica da TYRP-1, TYRP-2 e do MITF. Por fim, observou-se redução do mecanismo de resistência a multidrogas (transportadores ABC). Quanto aos glicoconjugados, houve uma clara redução da secreção de ácido hialurônico e da expressão gênica de hialuronidases. Ainda, foi evidente a redução da expressão gênica de proteoglicanos e de enzimas que modificam heparam sulfato. Esses resultados em conjunto sugerem que características fenotípicas metastáticas são modificadas pelo tratamento com M1 e M8, justificando os resultados anteriores encontrados in vitro e in vivo. Assim, esses complexos podem ser considerados candidatos promissores na terapia do câncer, embora estudos mais aprofundados devam ser realizados para melhor entendimento dos seus mecanismos de ação. Abstract: Melanoma is a highly metastatic skin cancer type. Conventional chemotherapy drugs currently in used are of limited value, thus more effective therapies are needed. This work aimed at investigation and elucidation of possible changes in tumor cell features triggered by highly diluted natural complex (M1 and M8) in vitro treatment using B16F10 melanoma cells. For this, cells were treated upon 96h with either M1 or M8 and several parameters were analyzed, focusing on possible changes in mRNA expression of invasion related proteins, migration and proliferation; and evaluation of reactive species; melanogenese and multidrug resistance mechanism. Finally, glycoconjugates evaluation was performed. The results clearly demonstrated that M1 and M8 treatment accounts to reduction in metastasis related features important by decreasing metaloproteases gene expression (MT1-MMP, MMP-2 and MMP-9), and your gelatinase activity, as well as cell migration. The latter was, possibly due to increased reactive oxygen (ROS), release of nitric oxide (NO) and reduction intracellular NO. Interestingly this effect was accompanied by melanin synthesis reduction and activity and expression reduction of tyrosinase (TYR), as well as TYRP-1, TYRP-2 and MITF expression. Finally, was observed reduction of drugs resistance mechanism (ABC transporters). As for glycoconjugates, there was a clear reduction in the secretion of hyaluronic acid and the gene expression of hyaluronidases. Still, it was evident the reduction of gene expression of proteoglycans and heparan sulfate enzymes modifiers. Taken together these findings suggest that metastatic phenotypic characteristics are modified by M1 and M8 treatment, justifying previous in vitro and in vivo findings. Thus these complexes can be considered as promising cancer therapy candidates, although further studies should be conducted to better understand their way of action.

Muitas plantas são utilizadas pela população para o tratamento e a cura de doenças. Entre elas encontram-se a Persea major Kopp, Piper mollicomum Kunth. e Serjania erecta Radlk. as quais são utilizadas para diversas enfermidades, inclusive para tratar distúrbios do trato gastrointestinal. O objetivo deste trabalho foi estudar os efeitos dos extratos dessas três plantas sobre a motilidade gastrointestinal. Camundongos Swiss foram tratados com os extratos pela via oral 1 hora antes da administração de uma solução semisólida de carboximetilcelulose 1,5% e vermelho de fenol 0,05% e, após 15 minutos, o esvaziamento gástrico e o trânsito intestinal avaliados. O extrato hidroalcoólico da P. major (100 a 1000 mg Kg-1, p.o.) e o extrato hidroalcoólico da P. mollicomum (100 e 300 mg Kg-1, p.o.) aumentaram o trânsito intestinal. No entanto, somente o extrato da P. major (100 e 300 mg Kg-1) também aumentou o esvaziamento gástrico. O extrato etanólico da S. erecta (100 a 1000 mg Kg-1, p.o.) não alterou a motilidade gastrointestinal. Estes resultados sugerem que a Persea major e a Piper mollicomum mereçam estudos mais aprofundados em busca de princípios ativos ou matéria vegetal efetiva para o tratamento de distúrbios do trato gastrointestinal como a constipação. Many plants are popularly used for the treatment and healing of diseases. The Persea major Kopp, Piper mollicomum Kunth. and Serjania erecta Radlk. are used in several illnesses, including the treatment of disorders of the gastrointestinal tract. The aim of this study was to evaluate the effects of the extracts of these plants on the gastrointestinal motility. Swiss mice were orally treated with extracts one hour before the administration of a semisolid solution of 1.5% carboxymethylcellulose and 0.05% phenol red. After 15 minutes, the gastric emptying and intestinal transit were determined. The hydroalcoholic extract of P. major (100 to 1000 mg Kg-1, p.o.) and the hydroalcoholic extract of P. mollicomum (100 and 300 mg Kg-1, p.o.) increased the intestinal transit. However, only the P. major extract (100 and 300 mg Kg-1) increased the gastric emptying. The ethanolic extract of S. erecta (100 to 1000 mg Kg-1, p.o.) did not alter the gastrointestinal motility. These results suggest that Persea major and Piper mollicomum can be of interest for further studies in the search of active principles or effective plant material for the treatment of disorders of the gastrointestinal tract, such as constipation.

Type II arabinogalactan (AG) is a polysaccharide found in Maytenus ilicifolia (Celastraceae), a plant reputed as gastroprotective. Oral and intraperitoneal administration of the AG protected rats from gastric ulcers induced by ethanol. No alteration of mechanisms related to acid gastric secretion and gastrointestinal motility were observed. In vitro, the AG showed a potent scavenging activity against the radical of DPPH (2,2-diphenyl-1-picrylhydrazyl) with an IC50 value of 9.3 μM. However, the mechanism of the gastroprotective action remains to be identified.

Achillea millefolium L. is a member of the Asteraceae family that is commonly referred to as “yarrow” and has been used in folk medicine against several disturbances including skin inflammations, spasmodic and gastrointestinal disorders, as well as hepato-biliary complaints. Aim of the study In the present study, we evaluated the efficacy of a hydroalcoholic extract from the Achillea millefolium (HE) for gastroprotective properties and additional mechanism(s) involved in this activity. Material and methods Rats were treated with HE and subsequently exposed to both acute gastric lesions induced by ethanol P.A. and chronic gastric ulcers induced by 80% acetic acid. Following treatment, glutathione (GSH) levels and superoxide dismutase (SOD) activity were measured. The activity of myeloperoxidase (MPO) and histological and immunohistochemical analysis were performed in animals with acetic acid-induced gastric ulcers. Results Oral administration of HE (30, 100 and 300 mg/kg) inhibited ethanol-induced gastric lesions by 35, 56 and 81%, respectively. Oral treatment with HE (1 and 10 mg/kg) reduced the chronic gastric ulcers induced by acetic acid by 43 and 65%, respectively, and promoted significant regeneration of the gastric mucosa after ulcer induction denoting increased cell proliferation, which was confirmed by PCNA immunohistochemistry. HE treatment prevented the reduction of GSH levels and SOD activity after acetic acid-induced gastric lesions. In addition, HE (10 mg/kg) inhibited the MPO activity in acetic acid-induced gastric ulcers. Conclusions The results of the present study indicate that the antioxidant properties of HE may contribute to the gastroprotective activity of this extract.