Tribological behavior of bioactive multi-material structures targeting orthopedic applications.

The following study proposes a multi-material solution in which Ti6Al4V cellular structures produced by Selective Laser Melting are impregnated with bioactive materials (hydroxyapatite or ß-tricalcium phosphate) using press and sintering technique. To assess the tribological response of these structures, an alumina plate was used as a counterpart in a flat-on-flat reciprocating sliding test. Ti6Al4V cellular structures impregnated with bioactive materials displayed the highest wear resistance when compared with the unreinforced structures. Among the bioactive structures, Ti6Al4V cellular structures impregnated with ßTCP were the ones with higher wear resistance, having the lowest weight loss. Hence, these structures are promising multifunctional solutions for load-bearing applications by gathering suitable mechanical properties (strength and stiffness); bioactive properties and in addition an improved wear performance.

Traditional knowledge and uses of medicinal plants by the inhabitants of the islands of the São Francisco river, Brazil and preliminary analysis of Rhaphiodon echinus (Lamiaceae) / Conhecimento tradicional e usos de plantas medicinais por habitantes das ilhas do rio São Francisco, Brasil e análise preliminar de Rhaphiodon echinus (Lamiaceae)

Abstract This study aimed to carry out an ethnobotanical survey of medicinal plants used by inhabitants of the Rodeadouro Island, Jatoba Island and Massangano Island, located in The Submedium São Francisco River Valley. Also phytochemicals and preliminary pharmacological tests were performed to species most cited by the community. Ethnobotanical data were collected through observation visits and semi-structured interviews with 12 key informants. We calculated the relative importance (RI), the percentage of agreement related to the main uses (cAMU) and use value (UV). The aerial parts of Rhaphiodon echinus (Ness & Mart.) Schauer were used to obtain the lyophilizate (LYO-Re), crude ethanol extract (CEE-Re) and their hexanic (HEX-Re), chloroform (CLO-Re) and ethyl acetate (EA-Re) fractions. The microdilution technique was used for determining Minimum inhibitory concentration (MIC) for selected microorganisms. Already the spasmolytic effect was evaluated in isolated uterus fragments of Wistar rats, pre contracted with KCl 60 mM. We found 34 species cited, belonging to 22 families. The most plants were grown by locals. There were 51 different diseases, but the main indication was infectious and parasitic diseases. The species R. echinus was the most reported and it was indicated for urinary tract infection and dysmenorrhea. The screening revealed a higher prevalence of flavonoids, tannins, lignans and saponins in LYO-Re and AE-Re. Already terpene compounds were more present in HEX-Re and CLO-Re. The RE-Re fraction stood out with strong effect against E. coli and S. aureus while CEE-Re has moderate effect against gram-negative bacteria. The evaluation of the spasmolytic activity showed that LYO-Re, CEE-Re and HEX-Re fractions have similar activity, with partial effect and concentration-dependent response. This work brought about knowledge and use of medicinal plants by the riparian of the São Francisco River. It also revealed the importance of other methodologies for scientific evidence for the popular use of R. echinus.

Resumo Objetivou-se realizar um levantamento etnobotânico de plantas medicinais utilizadas nas ilhas do Massangano, Jatobá II e Rodeadouro, localizadas entre Petrolina-PE e Juazeiro-BA, no submédio do rio São Francisco e posterior investigação fitoquímica e farmacológica da espécie mais citada, conforme a indicação da comunidade. Realizaram-se visitas de observação nas ilhas e os dados etnobotânicos foram coletados por entrevistas semiestruturadas com 12 informantes-chave. Calculou-se a Importância Relativa (IR), a Porcentagem Corrigida de Concordância quanto ao Uso Principal (CUPc) e o Valor de Uso (VU). Utilizaram-se as partes aéreas da espécie mais citada para obtenção do extrato etanólico bruto (EEB-Re), suas frações hexânica (HEX-Re), clorofórmica (CLO-Re) e acetato de etila (AE-Re); o produto liofilizado (LIO-Re) e o óleo essencial (OE-Re). A técnica de microdiluição foi usada para determinar a Concentração Inibitória Mínima (CIM) para microorganismos selecionados. A atividade espasmolítica foi avaliada em fragmentos isolados de útero de ratas Wistar pré-contraídos com KCl 60 mM. Foram relatadas 34 espécies, contidas em 22 famílias diferentes. A maioria das plantas era cultivada pelos moradores. Registraram-se 51 enfermidades diferentes, mas a principal indicação foi doenças parasitárias e infecciosas. A espécie Rhaphiodon echinus (Ness & Mart.) Schauer foi a mais citada, com principal indicação para tratar infecção do trato urinário e dismenorreia. O screening fitoquímico revelou prevalência de flavonoides, taninos, lignanas e saponinas em LIO-Re e AE-Re e compostos terpênicos em HEX-Re e CLO-Re. Os testes antibacterianos mostraram que AE-Re é mais atuante contra E. coli e S. aureus do que para P. aeruginosa. O EEB-Re tem efeito parcial contra bactérias gram-negativas e OE-Re possui moderada resposta para todos microorganismos testados. LIO-Re, EEB-Re e HEX-Re possuem atividade espasmolítica dependente da concentração, sem diferença significativa e sem relaxamento total. Este trabalho trouxe conhecimento sobre o uso de plantas medicinais pelos ribeirinhos do rio São Francisco e revela a importância de estudos mais aprofundados para a comprovação científica do uso popular da R. echinus.

Traditional knowledge and uses of medicinal plants by the inhabitants of the islands of the São Francisco river, Brazil and preliminary analysis of Rhaphiodon echinus (Lamiaceae).

This study aimed to carry out an ethnobotanical survey of medicinal plants used by inhabitants of the Rodeadouro Island, Jatoba Island and Massangano Island, located in The Submedium São Francisco River Valley. Also phytochemicals and preliminary pharmacological tests were performed to species most cited by the community. Ethnobotanical data were collected through observation visits and semi-structured interviews with 12 key informants. We calculated the relative importance (RI), the percentage of agreement related to the main uses (cAMU) and use value (UV). The aerial parts of Rhaphiodon echinus (Ness & Mart.) Schauer were used to obtain the lyophilizate (LYO-Re), crude ethanol extract (CEE-Re) and their hexanic (HEX-Re), chloroform (CLO-Re) and ethyl acetate (EA-Re) fractions. The microdilution technique was used for determining Minimum inhibitory concentration (MIC) for selected microorganisms. Already the spasmolytic effect was evaluated in isolated uterus fragments of Wistar rats, pre contracted with KCl 60 mM. We found 34 species cited, belonging to 22 families. The most plants were grown by locals. There were 51 different diseases, but the main indication was infectious and parasitic diseases. The species R. echinus was the most reported and it was indicated for urinary tract infection and dysmenorrhea. The screening revealed a higher prevalence of flavonoids, tannins, lignans and saponins in LYO-Re and AE-Re. Already terpene compounds were more present in HEX-Re and CLO-Re. The RE-Re fraction stood out with strong effect against E. coli and S. aureus while CEE-Re has moderate effect against gram-negative bacteria. The evaluation of the spasmolytic activity showed that LYO-Re, CEE-Re and HEX-Re fractions have similar activity, with partial effect and concentration-dependent response. This work brought about knowledge and use of medicinal plants by the riparian of the São Francisco River. It also revealed the importance of other methodologies for scientific evidence for the popular use of R. echinus.

Cytotoxic and genotoxic effects of acitretin, alone or in combination with psoralen-ultraviolet A or narrow-band ultraviolet B-therapy in psoriatic patients.

Acitretin is currently used alone or combined with PUVA (psoralen + UVA) or with narrow-band ultraviolet B (NBUVB), to treat moderate and severe psoriasis. However, little is known about the potential genotoxic/carcinogenic risk and the cytostatic/cytotoxic effects of these treatments. Our aim was to study the cytotoxic and genotoxic effects of acitretin - alone or in combination with PUVA or NBUVB - by performing studies with blood from patients with psoriasis vulgaris who were treated with acitretin, acitretin+PUVA or acitretin+NBUVB for 12 weeks, and in vitro studies with blood from healthy volunteers, which was incubated with acitretin at different concentrations. The cytotoxic and genotoxic effects were evaluated by the cytokinesis-blocked micronucleus test and the comet assay. Our results show that psoriatic patients treated with acitretin alone or with acitretin+NBUVB, did not show genotoxic effects. In addition, these therapies reduced the rate of proliferation and induced apoptosis and necrosis of lymphocytes; the same occurred with lymphocyte cultures incubated with acitretin (1.2-20µM). The acitretin+PUVA reduced also the proliferation rate, and increased the necrotic lymphocytes. Our studies suggest that therapy with acitretin alone or combined with NBUVB, as used in psoriatic patients, does not show genotoxic effects, reduces the rate of proliferation and induces apoptosis and necrosis of lymphocytes. The combination of acitretin with PUVA also reduces the proliferation rate and increases the number of necrotic lymphocytes. However, as it induced slight genotoxic effects, further studies are needed to clarify its genotoxic potential.

Avaliação toxicológica pré-clínica do chá das folhas de Morus nigra L. (Moraceae) / Pre-clinical toxicological evaluation of tea from the leaves of Morus nigra L. (Moraceae)

O objetivo desse estudo foi realizar um ensaio toxicológico pré-clínico para analisar a toxicidade do chá das folhas de Morus nigra L. (Moraceae). A toxicidade subcrônica do chá (CF-Mn) foi avaliada durante 30 dias por via oral em ratos. Ao grupo controle foi administrado água, para comparação. Durante o período experimental foi avaliada a presença de sinais de toxicidade, variação do peso corporal, e o consumo de líquido e alimento. Ao final do experimento o sangue dos animais foi retirado para análise de parâmetros hematológicos e bioquímicos. Não foram observados mortalidade e sinais de toxicidade indicando baixa toxicidade da planta. Não houve alterações nos parâmetros hematológicos e bioquímicos. Nas condições do estudo, o CF-Mn pode ser considerado de baixa toxicidade, pois não produziu efeitos tóxicos nos animais tratados.

The aim of this study was to carry out a pre-clinical toxicological assay to analyze the toxicity of tea from the leaves of Morus nigra L. (Moraceae). The subchronic toxicity of this tea (CF-Mn) was orally evaluated during 30 days in rats. The control group was given water for comparison. During the experimental period, signs of toxicity, body weight variation, and water and food consumption were assessed. At the end of the experiment, the blood of animals was removed for analysis of hematological and biochemical parameters. No mortality and no toxicity signs were observed, indicating low toxicity of the plant. There was no alteration in the hematological and biochemical parameters. Under the study conditions, CF-Mn can be considered of low toxicity since it did not produce toxic effects in treated animals.

Chemopreventive activity of compounds extracted from Casearia sylvestris (Salicaceae) Sw against DNA damage induced by particulate matter emitted by sugarcane burning near Araraquara, Brazil.

Ethanolic extract of Casearia sylvestris is thought to be antimutagenic. In this study, we attempted to determine whether this extract and casearin X (a clerodane diterpene from C. sylvestris) are protective against the harmful effects of airborne pollutants from sugarcane burning. To that end, we used the Tradescantia micronucleus test in meiotic pollen cells of Tradescantia pallida, the micronucleus test in mouse bone marrow cells, and the comet assay in mouse blood cells. The mutagenic compound was total suspended particulate (TSP) from air. For the Tradescantia micronucleus test, T. pallida cuttings were treated with the extract at 0.13, 0.25, or 0.50 mg/ml. Subsequently, TSP was added at 0.3mg/ml, and tetrads from the inflorescences were examined for micronuclei. For the micronucleus test in mouse bone marrow cells and the comet assay in mouse blood cells, Balb/c mice were treated for 15 days with the extract-3.9, 7.5, or 15.0 mg/kg body weight (BW)-or with casearin X-0.3, 0.25, or 1.2 mg/kg BW-after which they received TSP (3.75 mg/kg BW). In T. pallida and mouse bone marrow cells, the extract was antimutagenic at all concentrations tested. In mouse blood cells, the extract was antigenotoxic at all concentrations, whereas casearin X was not antimutagenic but was antigenotoxic at all concentrations. We conclude that C. sylvestris ethanolic extract and casearin X protect DNA from damage induced by airborne pollutants from sugarcane burning.

Alternative methodology for isolation of biosurfactant-producing bacteria.

Wide biosurfactant application on biorremediation is limited by its high production cost. The search for cheaper biossurfactant production alternatives has guided our study. The use of selective media containing sucrose (10 g x L(-1)) and Arabian Light oil (2 g x L(-1)) as carbon sources showed to be effective to screen and maintain biosurfactant-producing consortia isolated from mangrove hydrocarbon-contaminated sediment. The biosurfactant production was assayed by kerosene, gasoline and Arabian Light Emulsification activity and the bacterial growth curve was determined by bacterial quantification. The parameters analyzed for biosurfactant production were the growth curve, salinity concentration, flask shape and oxygenation. All bacteria consortia screened were able to emulsify the petroleum derivatives tested. Biosurfactant production increased according to the incubation time; however the type of emulsification (non-aqueous phase or aqueous phase) did not change with time but with the compound tested. The methodology was able to isolate biosurfactant-producing consortia from superficial mangrove sediment contaminated by petroleum hydrocarbons and was recommended for selection of biosurfactant producing bacteria in tropical countries with low financial resources.

Alternative methodology for isolation of biosurfactant-producing bacteria

Wide biosurfactant application on biorremediation is limited by its high production cost. The search for cheaper biossurfactant production alternatives has guided our study. The use of selective media containing sucrose (10 g.L-1) and Arabian Light oil (2 g.L-1) as carbon sources showed to be effective to screen and maintain biosurfactant-producing consortia isolated from mangrove hydrocarbon-contaminated sediment. The biosurfactant production was assayed by kerosene, gasoline and Arabian Light Emulsification activity and the bacterial growth curve was determined by bacterial quantification. The parameters analyzed for biosurfactant production were the growth curve, salinity concentration, flask shape and oxygenation. All bacteria consortia screened were able to emulsify the petroleum derivatives tested. Biosurfactant production increased according to the incubation time; however the type of emulsification (non-aqueous phase or aqueous phase) did not change with time but with the compound tested. The methodology was able to isolate biosurfactant-producing consortia from superficial mangrove sediment contaminated by petroleum hydrocarbons and was recommended for selection of biosurfactant producing bacteria in tropical countries with low financial resources.

A ampla aplicação de biossurfactantes em biorremediação é limitada pelo seu alto custo de produção. A procura de alternativas de produção mais baratas motivou nosso estudo. O uso de meio seletivo, contendo sacarose (10 g.L-1) e óleo Arabe Leve (2 g.L-1), mostrou-se eficiente na triagem e manutenção de consórcios bacterianos isolados de sedimento de mangue contaminado com hidrocarboneto. A produção de biossurfactante foi avaliada pela Atividade Emulsificante do querosene, gasolina e Arabe Leve e a curva de crescimento foi determinada pela quantificação bacteriana. Os parâmetros analisados para a produção de biossurfactante foram: curva de crescimento, concentração da salinidade, forma do frasco e oxigenação. Todos os consórcios bacterianos pesquisados foram capazes de emulsificar os derivados de petróleo testados. A produção de biossurfactante aumentou de acordo com o tempo de incubação, entretanto, o tipo de emulsificação aquosa e não-aquosa não mudou com o tempo, mas com o composto testado. A metodologia permitiu o isolamento de consórcios bacterianos produtores de biossurfactante de sedimento superficial de mangue contaminado com hidrocarbonetos do petróleo, sendo indicada para seleção de bactéria produtora de biossurfactante em países tropicais com baixos recursos financeiros.

Uso de ansiolítico como terapêutica coadjuvante no manejo nutricional de pacientes com câncer gástrico / The use of an anciolytic agent as coadjuvant therapy in the nutritional management of patients with digestive cancer

A desnutriçäo e a ansiedade säo acompanhantes freqüentes das enfermidades malignas do aparelho digestivo, notadamente no contexto do tratamento pré e pós-operatório. Numa avaliaçäo clínica de enfermos portadores destes transtornos, foram investigados os possíveis benefícios da introduçäo de uma medicaçäo ansiolítica como coadjuvante para a recuperaçäo do estado geral e das condiçöes nutritivas destes pacientes