Plant metabolite 5-pentadecyl resorcinol is produced by the Amazonian fungus Penicillium sclerotiorum LM 5679 / O metabólito vegetal 5-pentadecil resorcinol é produzido pelo fungo amazônico Penicillium sclerotiorum LM 5679

Since the classic studies of Alexander Flemming, Penicillium strains have been known as a rich source of antimicrobial substances. Recent studies have identified novel metabolites produced by Penicillium sclerotiorum that have antibacterial, antifouling and pharmaceutical activities. Here, we report the isolation of a P. sclerotiorum (LM 5679) from Amazonian soil and carry out a culture-based study to determine whether it can produce any novel secondary metabolite(s) that are not thus-far reported for this genus. Using a submerged culture system, secondary metabolites were recovered by solvent extract followed by thin-layer chromatography, nuclear magnetic resonance, and mass spectroscopy. One novel secondary metabolite was isolated from P. sclerotiorum (LM 5679); the phenolic compound 5-pentadecyl resorcinol widely known as an antifungal, that is produced by diverse plant species. This metabolite was not reported previously in any Penicillium species and was only found once before in fungi (that time, in a Fusarium). Here, we discuss the known activities of 5-pentadecyl resorcinol in the context of its mode-of-action as a hydrophobic (chaotropicity-mediated) stressor.

Desde os estudos clássicos de Alexander Flemming, as cepas de Penicillium são conhecidas como uma fonte rica em substâncias antimicrobianas. Estudos recentes identificaram novos metabólitos produzidos pela espécie Penicillium sclerotiorum com atividades antibacteriana, anti-incrustante e farmacêutica. Aqui, relatamos o isolamento de uma colônia de P. sclerotiorum (LM 5679) do solo amazônico e relatamos também o estudo baseado em cultura para determinar se ele pode produzir qualquer novo metabólito (s) secundário (s) que não foram relatados até agora para este gênero. Usando um sistema de cultura submerso, os metabólitos secundários foram recuperados por extrato de solvente seguido por cromatografia em camada delgada, ressonância magnética nuclear e espectroscopia de massa. Um novo metabólito secundário foi isolado de P. sclerotiorum (LM 5679); o composto fenólico 5-pentadecil resorcinol que é amplamente conhecido como um antifúngico que é produzido por diversas espécies de plantas. Este metabólito não foi relatado anteriormente em nenhuma espécie de Penicillium, e foi encontrado apenas uma vez em fungos (Fusarium). Aqui, discutimos as atividades conhecidas do 5-pentadecil resorcinol no contexto de seu modo de ação como um estressor hidrofóbico (mediado pela caotropicidade).

Plant metabolite 5-pentadecyl resorcinol is produced by the Amazonian fungus Penicillium sclerotiorum LM 5679

Abstract Since the classic studies of Alexander Flemming, Penicillium strains have been known as a rich source of antimicrobial substances. Recent studies have identified novel metabolites produced by Penicillium sclerotiorum that have antibacterial, antifouling and pharmaceutical activities. Here, we report the isolation of a P. sclerotiorum (LM 5679) from Amazonian soil and carry out a culture-based study to determine whether it can produce any novel secondary metabolite(s) that are not thus-far reported for this genus. Using a submerged culture system, secondary metabolites were recovered by solvent extract followed by thin-layer chromatography, nuclear magnetic resonance, and mass spectroscopy. One novel secondary metabolite was isolated from P. sclerotiorum (LM 5679); the phenolic compound 5-pentadecyl resorcinol widely known as an antifungal, that is produced by diverse plant species. This metabolite was not reported previously in any Penicillium species and was only found once before in fungi (that time, in a Fusarium). Here, we discuss the known activities of 5-pentadecyl resorcinol in the context of its mode-of-action as a hydrophobic (chaotropicity-mediated) stressor.

Resumo Desde os estudos clássicos de Alexander Flemming, as cepas de Penicillium são conhecidas como uma fonte rica em substâncias antimicrobianas. Estudos recentes identificaram novos metabólitos produzidos pela espécie Penicillium sclerotiorum com atividades antibacteriana, anti-incrustante e farmacêutica. Aqui, relatamos o isolamento de uma colônia de P. sclerotiorum (LM 5679) do solo amazônico e relatamos também o estudo baseado em cultura para determinar se ele pode produzir qualquer novo metabólito (s) secundário (s) que não foram relatados até agora para este gênero. Usando um sistema de cultura submerso, os metabólitos secundários foram recuperados por extrato de solvente seguido por cromatografia em camada delgada, ressonância magnética nuclear e espectroscopia de massa. Um novo metabólito secundário foi isolado de P. sclerotiorum (LM 5679); o composto fenólico 5-pentadecil resorcinol que é amplamente conhecido como um antifúngico que é produzido por diversas espécies de plantas. Este metabólito não foi relatado anteriormente em nenhuma espécie de Penicillium, e foi encontrado apenas uma vez em fungos (Fusarium). Aqui, discutimos as atividades conhecidas do 5-pentadecil resorcinol no contexto de seu modo de ação como um estressor hidrofóbico (mediado pela caotropicidade).

Plant metabolite 5-pentadecyl resorcinol is produced by the Amazonian fungus Penicillium sclerotiorum LM 5679 / O metabólito vegetal 5-pentadecil resorcinol é produzido pelo fungo amazônico Penicillium sclerotiorum LM 5679

Since the classic studies of Alexander Flemming, Penicillium strains have been known as a rich source of antimicrobial substances. Recent studies have identified novel metabolites produced by Penicillium sclerotiorum that have antibacterial, antifouling and pharmaceutical activities. Here, we report the isolation of a P. sclerotiorum (LM 5679) from Amazonian soil and carry out a culture-based study to determine whether it can produce any novel secondary metabolite(s) that are not thus-far reported for this genus. Using a submerged culture system, secondary metabolites were recovered by solvent extract followed by thin-layer chromatography, nuclear magnetic resonance, and mass spectroscopy. One novel secondary metabolite was isolated from P. sclerotiorum (LM 5679); the phenolic compound 5-pentadecyl resorcinol widely known as an antifungal, that is produced by diverse plant species. This metabolite was not reported previously in any Penicillium species and was only found once before in fungi (that time, in a Fusarium). Here, we discuss the known activities of 5-pentadecyl resorcinol in the context of its mode-of-action as a hydrophobic (chaotropicity-mediated) stressor.

Desde os estudos clássicos de Alexander Flemming, as cepas de Penicillium são conhecidas como uma fonte rica em substâncias antimicrobianas. Estudos recentes identificaram novos metabólitos produzidos pela espécie Penicillium sclerotiorum com atividades antibacteriana, anti-incrustante e farmacêutica. Aqui, relatamos o isolamento de uma colônia de P. sclerotiorum (LM 5679) do solo amazônico e relatamos também o estudo baseado em cultura para determinar se ele pode produzir qualquer novo metabólito (s) secundário (s) que não foram relatados até agora para este gênero. Usando um sistema de cultura submerso, os metabólitos secundários foram recuperados por extrato de solvente seguido por cromatografia em camada delgada, ressonância magnética nuclear e espectroscopia de massa. Um novo metabólito secundário foi isolado de P. sclerotiorum (LM 5679); o composto fenólico 5-pentadecil resorcinol que é amplamente conhecido como um antifúngico que é produzido por diversas espécies de plantas. Este metabólito não foi relatado anteriormente em nenhuma espécie de Penicillium, e foi encontrado apenas uma vez em fungos (Fusarium). Aqui, discutimos as atividades conhecidas do 5-pentadecil resorcinol no contexto de seu modo de ação como um estressor hidrofóbico (mediado pela caotropicidade).

Plant metabolite 5-pentadecyl resorcinol is produced by the Amazonian fungus Penicillium sclerotiorum LM 5679.

Since the classic studies of Alexander Flemming, Penicillium strains have been known as a rich source of antimicrobial substances. Recent studies have identified novel metabolites produced by Penicillium sclerotiorum that have antibacterial, antifouling and pharmaceutical activities. Here, we report the isolation of a P. sclerotiorum (LM 5679) from Amazonian soil and carry out a culture-based study to determine whether it can produce any novel secondary metabolite(s) that are not thus-far reported for this genus. Using a submerged culture system, secondary metabolites were recovered by solvent extract followed by thin-layer chromatography, nuclear magnetic resonance, and mass spectroscopy. One novel secondary metabolite was isolated from P. sclerotiorum (LM 5679); the phenolic compound 5-pentadecyl resorcinol widely known as an antifungal, that is produced by diverse plant species. This metabolite was not reported previously in any Penicillium species and was only found once before in fungi (that time, in a Fusarium). Here, we discuss the known activities of 5-pentadecyl resorcinol in the context of its mode-of-action as a hydrophobic (chaotropicity-mediated) stressor.

Tuning the magnetic properties of Sn1-x-y Ce4+x Ce3+y O2 nanoparticles: an experimental and theoretical approach.

During the last decade, there was a substantial increase in the research on metal-doped oxide semiconductor nanoparticles due to advances in the engineering of nanomaterials and their potential application in spintronics, biomedicine and photocatalysis fields. In this regard, doping a nanomaterial is a powerful tool to tune its physicochemical properties. The aim of this work is to shine a new light on the role of the neighbouring elements on the oxidation state of the Ce-impurity, from both experimental and theoretical points of view. Herein, we present an accurate study of the mechanisms involved in the oxidation states of the Ce-ions during the doping process of SnO2 nanoparticles (NPs) prepared by the polymeric precursor method. X-ray diffraction measurements have displayed the tetragonal rutile-type SnO2 phase in all samples. However, the Bragg's peak (111) and (220) located at 2θ ∼29° and ∼47° evidence the formation of a secondary CeO2 phase for samples with Ce content up to 10%. X-ray absorption near-edge structure (XANES) measurements, at Ce L3 edge, were performed on the NPs as a function of Ce content. The results show, on one side, the coexistence of Ce3+ and Ce4+ states in all samples; and on the other side, a clear reduction in the Ce3+ population driven by the increase of Ce content. It is shown that this is induced by the neighboring cation, and confirmed by magnetic measurements. The monotonic damping of the Ce3+/Ce4+ ratio experimentally, was connected with theoretical calculations via density functional theory by simulating a variety of point defects composed of Ce impurities and surrounding oxygen vacancies. We found that the number of oxygen vacancies around the Ce-ions is the main ingredient to change the Ce oxidation state, and hence the magnetic properties of Ce-doped SnO2 NPs. The presented results pave the way for handling the magnetic properties of oxides through the control of the oxidation state of impurities.

Eugenol as an efficient anesthetic for neotropical fish Prochilodus nigricans (Teleostei, Prochilodontidae) / [Eugenol como um anestésico eficaz para o peixe neotropical Prochilodus nigricans (Teleostei, Prochilodontidae)]

The use of anesthetics in fish farming is essential to reduce stress during management. The present study proposes to evaluate the effect of eugenol as an anesthetic for the management of curimatã (Prochilodus nigricans). Fifty specimens were used (221.34±9.0 g; 25.8 ±1.1 cm), submitted to five treatments with concentrations of 0, 25, 50, 100 and 200 mgL−1 eugenol for 10 min. The times required to reach each anesthetic stage and the recovery of each fish were recorded. To check bloodglucose levels individual blood samples were taken from the fish before immersion and after ten minutes of anesthetic exposure. Evaluation of the anesthetic effect ongills was performed by histopathological analysis. The concentration of 50 mgL−1 was within the ideal limit of three minutes recommended for surgical anesthesia induction and did not significantly increase glucose levels when compared to the control group (35.7±19.4 mg dL−1), besides not causing gill injuries. At this concentration the fish presented controlled blood glucose levels within the basal levels, besides not taking the risk to have later problems concernig mortality, because this concentration ensures the good health of the gills and good recovery of the animals.(AU)

O uso de anestésicos em pisciculturas é indispensável para reduzir o estresse durante o manejo. O presente trabalho propôs avaliar o efeito do eugenol como anestésico para manejo do curimatã (Prochilodus nigricans). Foram utilizados 50 espécimes (221,34±9,0 g; 25,8 ±1,1 cm), submetidos a cinco tratamentos com concentrações de 0, 25, 50, 100 e 200 mg L−1 de eugenol em exposição de 10 minutos. Foram registrados os tempos necessários para atingir cada estágio anestésico e a recuperação de cada peixe. Para verificação dos níveis de glicose sanguínea, foram realizadas coletas individuais de sangue dos peixes antes da imersão e após os 10 minutos de exposição ao anestésico. A avaliação do efeito do anestésico sobre as brânquias foi realizada por meio de análises histopatológicas. A concentração de 50 mg L−1 ficou dentro do limite ideal de três minutos preconizado para indução à anestesia cirúrgica e não elevou significativamente os níveis de glicose quando comparada ao grupo controle (35,7±19,4 mg dL−1), além de não provocar lesões branquiais. Nessa concentração, os peixes apresentaram níveis de glicose sanguínea controlada, dentro dos teores basais, além de não correrem o risco de apresentarem problemas posteriores em relação à mortalidade, pois essa concentração garante a boa saúde das brânquias e uma boa recuperação dos animais.(AU)

Avaliação cardiorrespiratória e de sedação da associação de dexmedetomidina-butorfanol-midazolam ou detomidina-butorfanol-midazolam em catetos (Pecari tajacu) / Cardiorespiratory and sedation evaluation of the combination of dexmedetomidine-butorphanol-midazolam or detomidine butorphanol-midazolam in collared peccaries (Pecari tajacu)

A presente pesquisa comparou os efeitos cardiorrespiratórios, hemogasométricos e sedativos da associação midazolam (0,41mg/kg) e butorfanol (0,31mg/kg) acrescida de detomidina (157µg/kg) (DTMB) ou dexmedetomidina (36µg/kg) (DXMB) em catetos. Catetos adultos (n=20) foram distribuídos em dois grupos, DTMB ou DXMB. As variáveis (FC, f, PAM, SpO2, EtCO2 e TR) foram avaliadas após aplicação dos fármacos. A sedação foi avaliada por meio de escala analógica visual, relaxamento muscular, postura e resposta auditiva. Foi realizada ANOVA, seguida de teste t pareado (paramétricos) e teste de Mann-Whitney rank-sum test (não paramétricos), com P<0,05. Não foi observada diferença estatística entre os grupos para o período de latência. Observou-se diferença significativa entre grupos para as variáveis f, PAM e SpO2, com maiores valores para DTMB, e EtCO2, com maiores valores para DXMB. Os dois grupos apresentaram redução da FC e da concentração de lactato, bem como aumento da concentração de bicarbonato. A SpO2 permaneceu abaixo de 90%, durante todo o período experimental, nos dois grupos estudados. Os animais dos dois grupos apresentaram sedação profunda e relaxamento muscular máximo. Conclui-se que os dois protocolos testados proporcionaram adequada sedação, podendo ser indicados para contenção química de catetos adultos.(AU)

The study compared the cardiorespiratory, hemogasometric and sedative effects of the combination of midazolam (0.41mg/kg) and butorphanol (0.31mg/kg) plus detomidine (157µg/kg) (DTMB) or dexmedetomidine (36µg/kg) (DXMB) in collared peccaries. Collared peccaries (n= 20) were divided into two groups, either DTMB or DXMB. The variables (FC, f, PAM, SpO2, EtCO2 and TR) were evaluated after application of the drugs. Sedation was assessed by visual analogue scale, muscle relaxation, posture and auditory response. ANOVA followed by paired t-test (parametric) and Mann Whitney Rank Sum Test (non-parametric) with P< 0.05 were performed. No statistical difference was observed for the latency period. A significant increase was observed between groups for the variables f, PAM and SpO2 with higher values for DTMB and EtCO2 with higher values for DXMB. The two groups presented a reduction in HR and lactate concentration, and an increase in bicarbonate concentration. SpO2 remained below 90% throughout the experiment in both groups. The animals of the two groups presented deep sedation and maximum muscle relaxation. It is concluded that the two protocols tested provided adequate sedation and could be indicated for chemical containment of collared peccaries.(AU)

Tailoring the physical and chemical properties of Sn1-xCoxO2 nanoparticles: an experimental and theoretical approach.

In this work, we present a coupled experimental and theoretical first-principles investigation on one of the more promising oxide-diluted magnetic semiconductors, the Sn1-xCoxO2 nanoparticle system, in order to see the effect of cobalt doping on the physical and chemical properties. Our findings suggest that progressive surface enrichment with dopant ions plays an essential role in the monotonous quenching of the surface disorder modes. That weakening is associated with the passivation of the oxygen vacancies as the Co excess at the surface becomes larger. Room-temperature 119Sn Mössbauer spectroscopy data analysis revealed the occurrence of a distribution of isomer shifts, related to the different non-equivalent surroundings of Sn4+ ions and the coexistence of Sn2+/Sn4+ at the particle surfaces provoked by the inhomogeneous distribution of Co ions, in agreement with the X-ray photoelectron spectroscopy measurements. Magnetic measurements revealed a paramagnetic behavior of the Co ions dispersed in the rutile-type matrix with antiferromagnetic correlations, which become stronger as the Co content is increased. Theoretical calculations show that a defect with two Co mediated by a nearby oxygen vacancy is the most likely defect. The predicted effects of this defect complex are in accordance with the experimental results.

Cartogenina associada à microperfuração do osso subcondral na reparação da cartilagem articular em equinos / Kartogenin associated to micro of the subchondral bone in the joint cartilage repair in horses

A reconstituição da cartilagem articular danificada por doenças de desenvolvimento, trauma e osteoartrite tem sido um grande desafio na veterinária. O objetivo do presente estudo foi avaliar o uso da cartogenina, uma molécula capaz de induzir diferenciação de células mesenquimais em condrócitos, associado ou não à técnica de microfratura na reparação de defeitos condrais induzidos na tróclea femoral de equinos. Foram utilizados seis equinos pesando em média (±DP) 342±1,58kg, com idade de 7,2±1,30 anos e escore corporal de 7,1±0,75, os quais foram submetidos à videoartroscopia para indução da lesão condral de 1cm2 na tróclea lateral do fêmur e à realização da técnica de microperfuração do osso subcondral de ambos os joelhos. Foram realizadas quatro aplicações semanais com 20µM de cartogenina intra-articular em um dos joelhos (grupo tratado) e solução de ringer com lactato na articulação contralateral (grupo controle). Os animais foram submetidos a avaliações física, radiográfica, ultrassonográfica, por um período de 60 dias. Não houve qualquer diferença estatística entre as articulações tratadas e as controle. A terapia com cartogenina, segundo protocolo utilizado, não produziu melhora clínica em lesões osteocondrais induzidas e tratadas com microperfurações na tróclea lateral do fêmur em equinos.(AU)

Articular cartilage reconstruction is still a challenge in Veterinary Medicine. The aim was to evaluate the therapeutic effects of kartogenin, a small molecule that promotes chondrocyte differentiation, in the repair of induced chondral defects pretreated with subchondral drilling. Six horses with a mean (± SD) weight of 342 ± 1.58Kg, aging 7.2 ± 1.30 years, and with a mean 7.1 ± 0.75 body score condition were used. In both stifles, a 1cm2 chondral defect was induced in the lateral femoral trochlea followed by treatment with subchondral drilling. Four intra-articular injections with kartogenin (20mM) were performed weekly in one stifle (treated group). The same procedure using saline solution was performed in the contralateral joint (control group). Clinical, radiographic, ultrasound evaluations were performed for a period of 60 days. No statistical differences were detected between groups in any of the studied variables. Although kartogenin has shown to improve articular cartilage repair in laboratory animal models, the same was not observed in this equine model. In conclusion, the kartogenin therapy, according to the used protocol, did not promote any clinical benefit in equine femoral trochlear defects pretreated with subcondral drilling.(AU)

Anestesia geral inalatória ou total intravenosa associada à anestesia subaracnoidea, em ovinos / General inhalation anesthesia or total intravenous associated with subarachnoid anesthesia in sheep

Avaliou-se a eficácia e a segurança anestésica em ovinos mantidos sob anestesia geral inalatória com isofluorano ou anestesia total intravenosa com propofol, ambas associadas à anestesia subaracnoidea. Quatorze ovinos foram pré-medicados com 0,3mg.kg-1 de morfina IM, e cinco minutos após, receberam 20mcg.kg-1 de detomidina IV. Posteriormente, foram alocados aleatoriamente em dois grupos: GISO (n=7), os quais foram induzidos à anestesia geral com 0,5mg.kg-1 de diazepam e 5mg.kg-1 de cetamina IV, e mantidos em anestesia geral inalatória com isoflurano diluído em oxigênio a 100%; e GPRO (n=7), induzidos com 4mg.kg-1 de propofol IV seguido inicialmente de infusão contínua na taxa de 0,3mg.kg-1.min-1. Para realização da osteotomia bilateral, todos os animais receberam 0,5mg.kg-1 de ropivacaína 0,75% associado a 0,1mg.kg-1 de morfina pela via subaracnoidea. Houve redução de 40% nos valores médios de frequência cardíaca após sedação em ambos os grupos, permanecendo em média 23% reduzida até o final da avaliação. A pressão arterial média aumentou 16%, após a indução anestésica no GISO, mas se reduziu até o final do procedimento, assim como no GPRO. A EtISO média foi de 0,57V% e a taxa média de infusão do propofol foi de 0,24mg.kg-1.min-1. Os tempos totais de cirurgia, anestesia e extubação foram de 66±9,8, 92±13,8 e 7,0±1,5 minutos no GISO e 56±2,4, 82,9±4,6 e 5,4±1,5 minutos no GPRO, não havendo diferença significativa entre grupos. A manutenção anestésica com isoflurano ou propofol promoveu plano anestésico similar com mínimos efeitos cardiovasculares ou hemogasométricos, que são bem tolerados em ovinos hígidos.

The purpose of this study was to evaluate the efficacy and safety of sheep submitted to inhalation anesthesia with isoflurane or total intravenous anesthesia with propofol, both associated with subarachnoid anesthesia. Fourteen animals were pre-medicated with 0.3mg.kg-1 morphine IM, and 5 minutes later received 20mcg.kg-1 detomidine IV. Then they were allocated into two groups: GISO (n=7), which were induced with 0.5mg.kg-1 of diazepam and 5mg.kg-1 of ketamine IV, and anesthesia maintenance was performed by isoflurane diluted in 100% oxygen; or GPRO (n=7), where animals were induced with 4mg.kg-1 propofol IV and subsequent maintenance anesthesia with its own infusion of 0.3mg.kg.min-1. To perform the bilateral tibial osteotomy, all animals received 0.5mg.kg-1 0.75% ropivacaine combined with 0.1mg.kg-1 morphine by the intrathecal route. There was a 40% reduction in mean heart rate after the sedative protocol in both groups, resulting in a 23% average reduction until the end of the review. Mean arterial pressure showed transient elevation of around 16%, after induction of anesthesia in GISO, but reducing it to the end of the procedure, as well as in GPRO. The average EtISO was 0.57 V% and average infusion rate of propofol was 0.24mg.kg-1.min-1. The total time of surgery, anesthesia and extubation was 66± 9.8, 92±7.0 and 13.8±1.5 minutes in GISO and 56±2.4, 82.9±4.6 and 5.4±1.5 minutes in GPRO. The maintenance of anesthesia with propofol or isoflurane produced similar anesthesia with minimal cardiovascular and blood gas effects, which are well tolerated in healthy sheep.

Isolation and characterization of 25 microsatellite DNA loci for Anopheles albitarsis sensu lato and inter-specific amplification in 5 congeneric species.

The Anopheles albitasis complex includes 6 species, and 3 are considered as malaria vectors in Brazil. Twenty-five polymorphic microsatellite DNA loci were isolated and characterized in 24-36 individuals from the neighborhood of Puraquequara, Manaus, Amazonas State, Brazil. The number of estimated alleles ranged from 2 to 10, the observed heterozygosity ranged from 0.182 to 0.897, and the expected heterozygosity ranged from 0.260 to 0.854. Eleven loci showed significant deviation from Hardy-Weinberg equilibrium. Eleven loci were cross-amplified successfully in 5 Anopheles species. These microsatellite loci will be useful in studies investigating population structure and evolutionary genetics in A. albitarsis sensu lato and other A. albitarsis complex species.

Hancornia speciosa Gomes induces hypotensive effect through inhibition of ACE and increase on NO.

ETHNOPHARMACOLOGICAL RELEVANCE: The leaves of Hancornia speciosa Gomes are popularly used in Brazil to treat diabetes and hypertension. Cardiovascular diseases are the main cause of death worldwide and their incidences are increasing in Brazilian population. The present study aimed to investigate the hypotensive effect and the mechanism of action of Hancornia speciosa Gomes. METHODS: A fraction of the ethanolic extract of leaves from Hancornia speciosa (SFH) was obtained and standardized by its content on rutin, bornesitol and quinic acid. Systolic blood pressure (SBP) of normotensive mice was measured by tail plethysmography. SFH was given orally and SBP was monitored for 5h. Angiotensin-converting enzyme (ACE) inhibitor activity of SFH (1mg/kg) or captopril (10mg/kg) was measured by colorimetric methods. Serum nitrite levels were measured by spectrophotometry. RESULTS: SFH induced a dose-dependent hypotensive effect in normotensive mice. The serum activity of ACE and the level of angiotensin II were significantly reduced by SFH and by captopril. Administration of SFH induced a significant increase on plasmatic level of nitrites and the systemic inhibition of nitric oxide synthase by L-NAME (20mg/kg) reduced the hypotensive effect of SFH. CONCLUSIONS: The present work demonstrated that Hancornia speciosa has a potent hypotensive effect in normotensive mice. The inhibition of ACE leading to reduction on angiotensin II and increase on NO levels might account for the hypotensive effect. These results support the use of Hancornia speciosa by traditional medicine as antihypertensive.

Effects of side-chain and electron exchange correlation on the band structure of perylene diimide liquid crystals: a density functional study.

The structural and electronic properties of perylene diimide liquid crystal PPEEB are studied using ab initio methods based on the density functional theory (DFT). Using available experimental crystallographic data as a guide, we propose a detailed structural model for the packing of solid PPEEB. We find that due to the localized nature of the band edge wave function, theoretical approaches beyond the standard method, such as hybrid functional (PBE0), are required to correctly characterize the band structure of this material. Moreover, unlike previous assumptions, we observe the formation of hydrogen bonds between the side chains of different molecules, which leads to a dispersion of the energy levels. This result indicates that the side chains of the molecular crystal not only are responsible for its structural conformation but also can be used for tuning the electronic and optical properties of these materials.

National character does not reflect mean personality trait levels in 49 cultures.

Most people hold beliefs about personality characteristics typical of members of their own and others' cultures. These perceptions of national character may be generalizations from personal experience, stereotypes with a "kernel of truth," or inaccurate stereotypes. We obtained national character ratings of 3989 people from 49 cultures and compared them with the average personality scores of culture members assessed by observer ratings and self-reports. National character ratings were reliable but did not converge with assessed traits. Perceptions of national character thus appear to be unfounded stereotypes that may serve the function of maintaining a national identity.

Colorectal cancer: lifestyle and dietary factors.

INTRODUCTION: Colorectal cancer is the most common tumor in the developed countries, and the number of new cases annualy is aproximately equal for men and women. Several environmental factors can interact in all steps of carcinogenesis. Lately the balance between genetic predisposition and these factors, including nutritional components and lifestyle behaviors, determines individual susceptibility to develop colorectal cancer. The aim of this study is to revise the references about lifestyle include diet, physical exercise, tobacco smoking and use of alcohol, and the risk of colorectal cancer in databases published during 1994-2004. DIETARY FACTORS: According to the reports high intake of red meat, and particularly of processed meat and positive energetic balance (high intake of total fat and carbohydrate) was associated with a moderate but significant increase in colorectal cancer risk. Convincing preventive factors include increase consumption of a wide variety of fruit and vegetable, particularly, dark-green leafy, cruciferous, a deep-yellow on tones, and fibre. LIFESTYLE: Physical activity as a means for the primary prevention of colorectal cancer. There is a probable synergic effect among physical inactivity, high energy intake and obesity and incidence of colorectal cancer. A growing body of evidence supports that avoidance overweight and the use of tobacco and alcohol is recommended to prevent colorectal cancer. CONCLUSION: Current data suggest that lifestyle modification including proper diet such as the ones rich in vegetable and poor in red meat and fat, regular physical activity and maintaining an appropriate body weight and avoiding the use of tobacco and alcohol may lead to reduce colorectal cancer risk.

Prevalence and risk factors for hepatitis C virus (HCV) infection among pregnant Brazilian women.

OBJECTIVES: To determine the prevalence and the risk factors associated with HCV infection among women at childbirth, and to assess potential for infectivity of anti-HCV-positive women. METHODS: A total of 6995 women were interviewed and screened for HCV antibodies. Association and logistic regression analyses were conducted. RESULTS: The anti-HCV prevalence was 1.5% by EIA-3 and 0.8% by RIBA-3; HCV-RNA (RT-PCR) was detected in 74% of the RIBA-positive samples. Blood transfusion, race (blacks), alcohol abuse, a history of STD and anti-HBc positivity were independent risk factors for HCV positivity. Except for parenteral exposure, independent predictors of anti-HCV were a history of STD, anti-HBc positivity, a sex partner with multiple sex partners and a sex partner with a history of hepatitis. CONCLUSIONS: The prevalence of anti-HCV is higher in pregnant women than in blood donors. Sexual exposure may facilitate the spread of HCV and there is a high potential for mother-to-infant transmission.

Mechanisms of gene transfer mediated by lipoplexes associated with targeting ligands or pH-sensitive peptides.

Association of a targeting ligand such as transferrin, or an endosome disrupting peptide such as GALA, with cationic liposome-DNA complexes ('lipoplexes') results in a significant enhancement of transfection of several cell types (Simões S et al, Gene Therapy 1998; 5: 955-964). Although these strategies can overcome some of the barriers to gene delivery by lipoplexes, the mechanisms by which they actually enhance tranfection is not known. In studies designed to establish the targeting specificity of transferrin, we found that apo-transferrin enhances transfection to the same extent as transferrin, indicating that internalization of the lipoplexes is mostly independent of transferrin receptors. These observations were reinforced by results obtained from competitive inhibition studies either by preincubating the cells with an excess of free ligand or with various 'receptor-blocking' lipoplexes. Transfection of cells in the presence of drugs that interfere with the endocytotic pathway provided additional insights into the mechanisms of gene delivery by transferrin- or GALA-lipoplexes. Our results indicate that transferrin-lipoplexes deliver transgenes by endocytosis primarily via a non-receptor-mediated mechanism, and that acidification of the endosomes is partially involved in this process.

Antiserum for insulin radioimmunoassay generated by an insulin derivative devoid of hypoglycemic activity.

A tetraiodinated derivative of bovine insulin, prepared at pH 1 with stable iodine, was unable to cause signs of hypoglycemia in doses up to 2.4 micrograms/g in fasting mice, when native insulin caused 100% mortality. In neutral and acidic solutions, in absence of chaotropic agents, it behaved as the monomer, and could be separated from less iodinated, active species, that appeared as dimers, by conventional gel filtration. To generate antibodies in guinea-pigs, the tetraiodinated insulin was injected in doses three times higher than native insulin, without any harm to recipient animals. The induced antiserum was compared with antiserum generated by conventional methods in radioimmunoassay (RIA) of native insulin, and parallel curves were obtained.

Partition of Ca2+ antagonists in brain plasma membranes.

The partition coefficients (Kp) of three prototype Ca2+ antagonists, nitrendipine, (-)-desmethoxyverapamil and flunarizine were determined in native synaptic plasma membranes (SPM) isolated from sheep brain cortex and in liposomes prepared with the total lipids extracted from the membranes. We found that at 25 degrees and at 5 x 10(-6) M drug concentration the Kp values of the drugs for native SPM are higher than those obtained for liposomes, and are of the order of 334 +/- 53, 257 +/- 36 and 23 X 10(3) for nitrendipine, (-)desmethoxyverapamil and flunarizine, respectively, whereas the Kp values in liposomes are 190 +/- 41, 118 +/- 10 and 6 x 10(3) for the same drugs. The results suggest that the presence of membrane proteins favors the incorporation of the drugs in the membranes. Furthermore, the Kp values of the three Ca2+ antagonists studied increase with temperature in native membranes, but not in liposomes. It is concluded that the physical partitioning in membranes of drugs which act on Ca2+ channels may play some role in the mechanism of interaction of these drugs with the Ca2+ channel proteins.