Abstract Introduction This study evaluated the effect of the polymer polyvinylalcohol-carbazate (PVAC) on the bacteria Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. PVAC is a polymer with a carbazate moiety that neutralizes free aldehydes and has shown great promise in stabilizing erythrocytes during long term storage. It has also been shown to reduce intraperitoneal adhesions after trauma. For this study, two Gram positive and two Gram negative bacteria strains were used with PVAC to evaluate its effect. Materials and methods PVAC was obtained from the research team at Ångström Laboratory, Uppsala. The bacteria were obtained from Clinical Microbiology and Hospital Hygiene, Academic Hospital, Uppsala. The methods used were spectrophotometric assessment of bacteria growth, use of FITC-conjugated PVAC to study adherence to bacteria, use of FITC-antibodies to study PVAC’s effect on bacterial adherence to erythrocytes and a qPCR for quantification of E. coli. Results and discussion PVAC displayed a clear effect of inhibition of bacteria growth in the study as shown by use of spectrophotometric assessment. Trials with FITC-PVAC showed that the polymer adheres directly to the bacteria, displaying a possible function of its inhibitory properties. The qPCR assay was able to detect the bacteria in all the dilutions used. Introduction This study evaluated the effect of the polymer polyvinylalcohol-carbazate (PVAC) on the bacteria Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa. PVAC is a polymer with a carbazate moiety that neutralizes free aldehydes and has shown great promise in stabilizing erythrocytes during long term storage. It has also been shown to reduce intraperitoneal adhesions after trauma. For this study, two Gram positive and two Gram negative bacteria strains were used with PVAC to evaluate its effect. Materials and methods PVAC was obtained from the research team at Ångström Laboratory, Uppsala. The bacteria were obtained from Clinical Microbiology and Hospital Hygiene, Academic Hospital, Uppsala. The methods used were spectrophotometric assessment of bacteria growth, use of FITC-conjugated PVAC to study adherence to bacteria, use of FITC-antibodies to study PVAC’s effect on bacterial adherence to erythrocytes and a qPCR for quantification of E. coli. Results and discussion PVAC displayed a clear effect of inhibition of bacteria growth in the study as shown by use of spectrophotometric assessment. Trials with FITC-PVAC showed that the polymer adheres directly to the bacteria, displaying a possible function of its inhibitory properties. The qPCR assay was able to detect the bacteria in all the dilutions used.

A fosfolipase A2 (PLA2) é considerada uma enzima chave no metabolismo de fosfolípides, principais constituintes das membranas celulares. Alterações da atividade da PLA2 têm sido descritas no cérebro e sangue (soro, plasma e plaquetas) de pacientes com diversas doenças neuropsiquiátricas e também em matrizes biológicas como tecido cerebral de ratos e cultura de células neuronais. A inibição da atividade da PLA2 em cultura primárias de neurônios corticais de rato resultou em neurotoxicidade, o que demonstra o papel da PLA2 em processos de sobrevivência e desenvolvimento neuronal. Neste estudo foi padronizado um ensaio radioenzimático para caracterização dos três principais subtipos da PLA2 em cultura primária de neurônios: PLA2 secretória dependente de cálcio (sPLA2), PLA2 citosólica dependente de cálcio (cPLA2) e PLA2 intracelular independente de cálcio (iPLA2). Para isso foram testadas variáveis críticas para a reação enzimática e com os resultados obtidos houve um aprimoramento do método empregado. Foi encontrada ainda, uma predominância do subtipo iPLA2 (71%) nas culturas de neurônios. Dessa forma, apresentamos um modelo in vitro para determinação da atividade dos subtipos de PLA2 que pode ser considerado uma ferramenta para compreensão dos mecanismos envolvidos nas doenças neuropsiquiátricas, nas quais a PLA2 encontra-se alterada. Além disso, a partir de modelos laboratoriais baseados em estudos com culturas de células, poderão ser evidenciados os efeitos de diversas substâncias químicas novas ou de uso tradicional, como drogas de interesse psiquiátrico, sobre os neurônios. / The phospholipase (PLA2) is considered a key enzyme in the metabolism of phospholipids, which are the main constitutes of cellular membranes. Alterations in PLA2 activity have been reported in the brain and blood cells of psychiatric patients and also in biological matrixes like rat brain tissues and cultures of neuron cells. Inhibition of PLA2 activity in primary cultures of rat neurons resulted in neurotoxicity, which demonstrates the role of PLA2 in survival processes and neuronal development. In this study, a radioenzymatic assay was standardized to detect the activity of the three main groups of PLA2, which are the calcium dependent secretory PLA2 (sPLA2), the cytosolic calcium dependent PLA2 (cPLA2) and the intracellular calcium independent PLA2 (iPLA2), in the culture of neurons. Critical variables for the enzymatic assay were tested and from the results the method used was modified. Our findings demonstrate that there is a predominance of iPLA2 subtype (71%) in cultures of rat neurons. So therefore we present an in vitro model which aims to determine the main activity of PLA2 subtypes and can be considered an investigative tool for comprehending the mechanisms involved in neuropsychiatric disorders that show alterations in PLA2 activity. Furthermore, the effects of new chemical and traditional substances, such as the drugs used in psychiatric treatments, can be evidenced in the neurons by the use of laboratorial models based on studies of neuron cultures.

O melanoma cutâneo maligno é uma lesão neoplásica originada nos melanócitos epidérmicos, sendo altamente invasiva e agressiva, com elevada taxa de mortalidade, cuja incidência vem aumentando nos últimos anos. O tratamento do melanoma é cirúrgico e os pacientes com metástase podem receber quimioterapia com cisplatina que ao formarem adutos com o DNA alteram o processo de replicação da célula cancerosa. Sugere-se que os sistemas de reparo do DNA tenham um papel importante na etiologia do melanoma (reparo deficiente) e no tratamento do mesmo (eficiente eliminação dos adutos). A identificação prévia da resposta dos pacientes com melanoma ao tratamento com cisplatina pode ser um indicador biológico importante na clínica oncológica. O presente trabalho teve como objetivo, a partir de linfócitos de sangue periférico de pacientes com melanoma e de controles, avaliar o dano no DNA antes e após a adição, in vitro, de cisplatina (10?M, 100?M e 250?M), além de estimar a capacidade de reparo do DNA, após a retirada da droga (1h, 2,5h e 5h). Foram utilizados os testes do micronúcleo (MN - dano basal) e do Cometa (dano basal, ação da cisplatina e reparo do DNA). A análise citogenética foi possível em 20 pacientes com melanoma (10 homens e 10 mulheres, média de 50,6 ± 5,9 anos) e 19 controles (9 homens e 10 mulheres, média de 49,9 ± 5,5 anos) que também responderam a um questionário sobre hábitos e tipos de exposição a fatores de risco ao melanoma. A frequência do dano basal pelo teste do MN e do Cometa em linfócitos de pacientes (MN = 1,2 ± 1,2 e Cometa = 59,3 ± 62,5) foi praticamente o dobro da observada nos controles (MN = 0,6 ± 1,0 e Cometa = 35,3 ± 18,6) embora a diferença entre os grupos, em ambos os testes, não tenha sido considerada estatisticamente significante (p=0,23 e p=0,85, respectivamente). O tratamento in vitro com cisplatina, em comparação com o dano basal, aumentou a frequência de Cometas nas três concentrações estudadas (10?M, 100?M e 250?M) tanto para os pacientes (65,50 ± 50,06, 72,74 ± 50,89 e 77,26 ± 44,16) quanto para os controles (66,53 ± 49,85, 66,53 ± 26,33 e 81,74 ± 43,12) diferença esta considerada significante somente para o grupo controle, nas três concentrações avaliadas (p=0,0175, p=0,0002, e p=0,0002, respectivamente). Quanto aos diferentes tempos de reparo (1h, 2,5h e 5h), após a retirada de cisplatina nas diferentes concentrações estudadas, verificou-se aumento na frequência média de Cometas tanto para os pacientes com melanoma (93,88 ± 33,7, 101,75 ± 35,7 e 99,31 ± 32,30) quanto para os controles (92,45 ± 38,4, 100,82± 38,8 e 100,81± 31,7), diferença que foi estatisticamente significante quando comparada ao dano basal observado nos pacientes (p<0,001) e nos controles (p<0,001). Resultados semelhantes foram observados quando comparados em conjunto os escores dos tempos de reparo com o escore obtido após tratamento com cisplatina nos pacientes (71,09 ± 48,2; p<=0,005) e nos controles (71,59 ± 40,5; p<=0,005). Os resultados obtidos parecem indicar um padrão de resposta semelhante em relação à cisplatina e ao reparo do DNA nos dois grupos de indivíduos avaliados. O período de incubação das células, após a retirada da cisplatina, bem como o número de indivíduos avaliados podem ter influenciado nos resultados obtidos. Por outro lado, a resposta observada nos linfócitos in vitro, pode não ser representativa do efeito in vivo da célula tumoral. Entretanto, a identificação de marcadores de resposta a tratamentos com quimioterápicos, a partir de linfócitos de sangue periférico pode ser uma estratégia de pesquisa importante na prática clínica, inclusive para o melanoma. / Cutaneous melanoma is a malignant tumor originated from epidermal melanocytes, highly invasive and aggressive, with high mortality, and incidence that has been increasing over the years. The treatment for melanoma is surgery and patients with metastasis may receive chemotherapy with cisplatin, that results in DNA adducts that alters the replication process in cancer cells. It is suggested that the DNA repair systems have an important role in the etiology of melanoma (risk due to deficient repair) and treatment efficiency (removal of DNA adducts can decrease the treatment results). The prior identification of the response of melanoma patients to treatment with cisplatin may be an important biological marker in clinical oncology. The aim of this study was to assess, in peripheral blood lymphocytes from melanoma patients and controls, the DNA damage before and after the addition of cisplatin (10?M, 100?M and 250?M), in vitro, and estimate the capacity of DNA repair after drug removal (1h, 2.5h and 5h). The micronucleus test (MN - basal DNA damage) and the Comet assay (basal DNA damage, action of cisplatin and DNA repair) were used for the evaluation. Cytogenetic analysis was performed in 20 melanoma patients (10 men and 10 women, average age 50.6 ± 5.9 years old) and 19 controls (9 men and 10 women, average age 49.9 ± 5.5 years old) who also answered a questionnaire on habits and types of exposure to risk factors for melanoma. The frequency of basal DNA damage by the MN test and the Comet assay in lymphocytes from patients (MN = 1.2 ± 1.2 and Comet = 59.3 ± 62.5) was nearly twice the observed in controls (MN = 0, 6 ± 1.0 and Comet = 35.3 ± 18.6), although the difference between the groups in both tests was not considered statistically significant (p = 0.23 and p = 0.85, respectively). The in vitro treatment with cisplatin, compared with the basal DNA damage, increased the frequency of Comets in the three studied concentrations (10?M, 100?M and 250?M) for patients (65.50 ± 50.06, 72.74 ± 50.89 and 77.26 ± 44.16) and for the controls (66.53 ± 49.85, 66.53 ± 26.33 and 81.74 ± 43.12) and the difference was statistically significant only for the control group, for all cisplatin concentrations (p = 0.0175, p = 0.0002 and p = 0.0002, respectively). Considering the different repair times (1h, 2.5h and 5h), after removal of cisplatin at different concentrations, there was an increase in the mean frequency of Comets for both melanoma patients (93.88 ± 33.7, 101.75 ± 35.7 and 99.31 ± 32.30) and for the controls (92.45 ± 38.4, 100.82 ± 38.8 and 100.81 ± 31.7), and the difference was statistically significant when the repair Comet score was compared to the basal DNA damage observed in patients (p <0.001) and controls (p <0.001). Similar results were observed when the Comet scores of repair times were compared to the Comet scores obtained after treatment with cisplatin in patients (71.09 ± 48.2, p <= 0.005) and controls (71.59 ± 40.5, p <= 0.005). The results seem to indicate a similar pattern of response to cisplatin and DNA repair in both groups of subjects evaluated. The period of incubation of the cells after cisplatin removal and the number of individuals studied may have influenced the results. The lymphocytes\' response, in vitro, to cisplatin may not be representative of the in vivo effect of tumor cell. However, the identification of markers of response to treatment with chemotherapy from peripheral blood lymphocytes may be an important research strategy in clinical practice, including melanoma.

O crescimento cada vez maior da industrialização e a existência de um mercado globalizado vêm exigindo dos produtores rurais à utilização de modernas tecnologias ligadas à produção animal. O baixo custo de produção e o aumento da qualidade do produto final gerado têm sido a grande meta dos pecuaristas e centros de pesquisa voltados à agropecuária. Devido à necessidade de aumento na produção, propriedades agropecuárias têm recorrido ao uso de todo e qualquer recurso disponível que possa promover melhorias na atividade produtiva.O uso indiscriminado dos antimicrobianos com a intenção de aumentar a produção animal pode resultar em concentrações residuais nos produtos como carne, ovos e leite acima das doses aceitáveis para o consumo humano. Inicialmente, os antibióticos eram usados como medida terapêutica, mas com o avanço do conhecimento e desenvolvimento de novos compostos, passaram a ser utilizados também como medida preventiva e como promotores do crescimento.O que se deve questionar não é a presença destes resíduos, mas sim o tipo e as concentrações dos mesmos. De fato, as modernas tecnologias analíticas têm permitido a detecção de partes por bilhão de substâncias químicas, componentes ou metabólitos de medicamentos de uso veterinário em alimentos e, nestas quantidades, dificilmente elas representariam perigo à saúde dos consumidores. Portanto, há necessidade de se estabelecer metodologias analíticas mais eficientes que possam auxiliar os órgãos de fiscalização da agricultura no controle do uso desses antimicrobianos na produção animal. Assim como auxiliar no controle de qualidade, principalmente em indústrias exportadoras que almejam expansão de mercado, onde essa prática é quase uma imposição no contexto do comércio internacional de produtos pecuários \"in natura\" e processados. Devido a essas necessidades, o objetivo do presente foi padronizar e desenvolver reagentes imunoenzimáticos para a pesquisa da ciprofloxacina em produtos de origem animal. Os resultados obtidos no desenvolvimento desses imunoreagentes foram positivos quando correlacionado (r2 = 0,9588) com o kit referência RIDASCREEN® Enro/Cipro da R-Biopharm. Diante disso, é possível concluir que o Brasil possui infra-estrutura adequada para padronizar esses testes rápidos, evitando com isso um grande gasto na importação desses kits / The growth each time higher of industrialization and the existence of a global market forces the rural producers to use modern technologies related to animal production. The low production cost and the increasing of obtained final product quality have been the great aim of cattle farmers and cattle farming research centers. Due to the necessity of increasing the production, rural properties have required the use of any available source able to promote better productive activities. The indiscriminated antibiotics use aiming to increase animal production may result in residual concentrations found in products such as meat, eggs and milk over acceptable doses to the human consumption. Firstly, antibiotics were used as therapeutic prescriptions although the advances on knowledge and development of new compounds were also used as a preventive way and as growth promoters. What must be questionable its not the presence of these residuals but surely what kind of residual and their concentrations. In fact, the modern analytic technologies make possible the detection of parts per billions (ppb) of chemical substances, compounds or medicine metabolites of veterinary use in food and in these quantities, hardly they would be dangerous to the consumer health. However, it\'s necessary to establish more efficient analytic methodologies to help on agriculture supervising organs in the control of these antibiotics use in the animal production. Thus, how to help in the quality control, mainly in industries that export to get the market expansion, where this activity is almost an imposition at the international trade context of farming products \"in natura\" and industrialized ones. Due to these necessities, the goal of our present work was to standard and develop immunoenzymatics reagents to the ciprofloxacin researching from animal products. The results obtained on development of these immunoreagents were positive when correlated (r2= 0,9588) to the kit RIPASCREEN® Enro/Cipro from R-Biopharm reference. At the light of these knowledge, it?s possible to conclude that Brazil has adequate proper-structure to standardize these quick tests, to avoid in this way a high cost to import these kits.

O guajiru (Chrysobalanus icaco L.) é um fruto rico em antocianinas, as quais exercem vários efeitos benéficos à saúde. Embora as folhas do guajiru sejam utilizadas na medicina popular como hipoglicemiante e antioxidante, os efeitos do fruto na saúde permanecem inexplorados. O objetivo deste estudo foi avaliar os efeitos do fruto do guajiruzeiro sobre danos ao DNA e estresse oxidativo in vivo e inflamação in vitro e in vivo. Ratos machos Wistar (4-5 semanas, 110 g) foram divididos em oito grupos e tratados por 14 dias com água ou fruto do guajiruzeiro liofilizado (100, 200 ou 400 mg/kg p.c.) por gavagem. No 14º dia, os animais receberam solução fisiológica ou DXR (15 mg/kg p.c. i.p.) e foram eutanasiados após 24 horas. A genotoxicidade e antigenotoxicidade foram avaliadas pelo ensaio do cometa em sangue periférico, fígado, rins e coração. A mutagenicidade e antimutagenicidade foram investigadas pelo teste do micronúcleo em medula óssea e sangue periférico. O burst oxidativo foi avaliado em neutrófilos do sangue periférico. Parâmetros de estresse oxidativo envolveram: concentração de substâncias reativas ao ácido tiobarbitúrico, razão glutationa reduzida e oxidada e atividade da catalase em fígado, rins e coração. As expressões de genes de dano/reparo de DNA Gadd45a (growth arrest and DNA damage-inducible alpha), Parp1 (Poly(ADP-ribose) polymerase 1) e Xrcc2 (X-Ray Repair complementing defective repair in Chinese hamster cells 2) e dos marcadores pró-inflamatórios Il-1? (interleukin 1 beta), Il-6 (interleukin 6), Nf-kb (nuclear factor kappa B) e Tnf-? (tumor necrosis factor alpha) foram realizadas por PCR quantitativo em tempo real. Células de cólon humano CCD-18Co (fibroblastos) e HT-29 (adenocarcinoma) foram tratadas com antocianinas do guajiru (1,0 a 20,0 mg/L equivalentes de ácido gálico - GAE) e as expressões de IL-1?, IL-6, NF-kB e TNF-? analizadas a nível de RNA mensageiro e proteína. TNF-? foi utilizado para induzir inflamação em células CCD- 18Co. Os polifenois do fruto do guajiruzeiro foram quantificados/caracterizados por métodos cromatográficos e espectrométricos. As concentrações de 19 elementos químicos foram determinadas por plasma indutivamente acoplado a espectrometria de massas. Delfinidina, cianidina, petunidina e peonidina foram as antocianinas majoritárias encontradas no fruto. Concentrações significantes de polifenois, magnésio e selênio foram encontradas nesse fruto. O fruto do guajiruzeiro exibiu atividade antioxidante in vivo em neutrófilos, antigenotoxicidade em sangue periférico e antimutagenicidade em sangue periférico e medula óssea. O guajiru diminuiu os danos ao DNA no fígado, rins e coração. O fruto também diminuiu as expressões de Gadd45a, Il-1?, e Tnf-? nos tecidos. A proliferação celular foi suprimida em células HT-29, acompanhado por aumento na produção de ROS e diminuição nas expressões de TNF-?, IL-1?, IL-6 e NF-kB. Não foi observado efeito citotóxico das antocianinas em células CCD-18Co. As expressões das proteínas IL- 1?, IL-6 e TNF-? foram reduzidas em células CCD-18Co tratadas com TNF-? e com as antocianinas. Os resultados deste trabalho demonstram que os fitoquímicos e elementos químicos no fruto do guajiruzeiro possuem efeitos antigenotóxico, antimutagênico, antioxidante e anti-inflamatório e encorajam a realização de outros ensaios in vivo e estudos clínicos com esse fruto subutilizado. / Guajiru (Chrysobalanus icaco L.) is a fruit rich in anthocyanins, which exert several beneficial effects on health. Although guajiru leaves are used in folk medicine as hypoglycemic and antioxidant, the fruit effects on health remain unknown. The aim of this study was to evaluate the effects of guajiru fruit against in vivo DNA damage and oxidative stress and in vivo/in vitro inflammation. Male Wistar rats (4-5 weeks old, 110 g) were divided into eight groups and treated for 14 days with water or lyophilized guajiru fruit (100, 200 or 400 mg/kg b.w.) by gavage. On the 14th day, animals received physiologic solution or DXR (15 mg/kg b.w. i.p.) and were euthanized after 24 hours. Genotoxicity and antigenotoxicity were evaluated by comet assay in peripheral blood, liver, kidney, and heart. Mutagenicity and antimutagenicity of guajiru fruit were investigated by micronucleus test in peripheral blood and bone marrow. The oxidative burst was measured in peripheral blood neutrophils. Oxidative stress parameters involved the concentration of thiobarbituric acid reactive substances, reduced/oxidized glutathione ratio, and catalase activity in liver, kidney and heart. The expressions of DNA damage/repair genes Gadd45a (growth arrest and DNA damage-inducible alpha), Parp1 (Poly(ADP-ribose) polymerase 1), and Xrcc2 (X-Ray Repair complementing defective repair in Chinese hamster cells 2) and pro-inflammatory markers Il-1 ? (interleukin 1 beta), Il-6 (interleukin 6), Nf-kb (nuclear factor kappa B), and Tnf-? (tumor necrosis factor alpha) were evaluated by real-time quantitative PCR. Human colon cell lines CCD- 18Co (fibroblasts), and HT-29 (adenocarcinoma) were treated with guajiru anthocyanins (1.0 - 20.0 mg/L gallic acid equivalents - GAE) and the expressions of IL-1 ?, IL-6, NF-kB and TNF-? were analyzed at mRNA and protein levels. TNF-? was used to induce inflammation in CCD-18Co cells. Guajiru fruit phytochemicals were quantified and characterized by chromatographic and spectrometric methods. The concentrations of 19 chemical elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). Delphinidin, cyanidin, petunidin and peonidin were the major anthocyanins in this fruit. Significant amounts of phytochemicals, magnesium, and selenium were found in this fruit. Guajiru fruit displayed in vivo antioxidant activity in neutrophils, antigenotoxicity in peripheral blood and antimutagenicity in bone marrow and peripheral blood. Guajiru fruit decreased DNA damage in liver, kidney, and heart. This fruit decreased the expression of Gadd45a, Il-1 ?, and Tnf-?, in tissues. Cell proliferation was suppressed in HT-29 cells, and this was accompanied by increased intracellular ROS production as well as decreased TNF-?, IL-1 ?, IL-6, and NF-kB expressions. There was no cytotoxic effect of guajiru fruit anthocyanins in CCD-18Co cells. IL-1 ?, IL-6, and TNF-? protein expressions were reduced in TNF-?-treated CCD-18Co cells by guajiru fruit anthocyanins. The findings from this investigation demonstrated that phytochemicals and chemical elements in guajiru fruit possess antigenotoxic, antimutagenic, antioxidant and antiinflammatory effects and encourage other in vivo and clinical studies with this underutilized fruit.

Gastrointestinal (GI) alpha-synuclein (ASN) detection may represent a clinically useful biomarker of Parkinson's disease (PD), but this has been challenged by conflicting results of recent studies employing different immunohistochemical (IHC) methods and reporting diverse morphological patterns with variable biological interpretation. To increase sensitivity and specificity, we applied three different techniques to detect different possible conformations of ASN in GI tissue derived from biopsies of the GI tract, which were obtained from a longitudinally followed, clinically well-characterized cohort of PD subjects and healthy controls (HC) (Oxford Discovery study). With IHC, we used antibodies reactive for total (T-ASN-Abs), phosphorylated (P-ASN-Abs) and oligomeric (O-ASN-Abs) ASN; with the ASN Proximity Ligation Assay (AS-PLA), we targeted oligomeric ASN species specifically; finally, with the Paraffin-Embedded Tissue Blot (PET-Blot) we aimed to detect fibrillary conformations of ASN specifically. Optimisation and validation of the PET-Blot and PLA techniques was carried out with studies on brain tissue from subjects with ASN pathology, and these experiments were used to gain insight into morphology and distribution of different conformational variants of ASN in the brain of subjects with Lewy pathology. We specified all the detected morphological staining patterns with each technique interpreting them as pathologic or non-specific. Correlation to clinical symptoms was assessed to investigate the potential predictive or diagnostic value of specific staining patterns as biomarkers. A total of 163 GI tissue blocks were collected from 51 PD patients (113 blocks) and 21 healthy controls (50 blocks). In 31 PD patients, GI biopsies had been taken before PD diagnosis (Prodromal PD group); while in 20 PD patients biopsies were obtained after PD diagnosis (Manifest PD group). The majority of these tissues blocks were from large intestine (62%), followed by small intestine (21%), stomach (10%) and oesophagus (7%). With IHC, four ASN staining patterns were detected in GI tissue (Neuritic, Ganglionic, Epithelial, and Cellular), while two distinct staining patterns were detected with AS-PLA (cellular and diffuse signal) and with AS-PET-Blot (ASN-localised and peri-crypt signal). The level of agreement between different techniques was generally low, and no single technique or staining pattern was able to reliably distinguish PD patients (Prodromal or Manifest) from HC. Overall, our study suggests that even specific detection of ASN conformational variants currently considered pathologic was not adequate for the prediction of PD. Future studies with these or other novel techniques focusing on the upper part of the GI tract could overcome current limitations in sensitivity and specificity.

Os organismos vivos estão expostos à ação oxidativa de espécies reativas de oxigênio (ERO), causando uma série de doenças degenerativas como câncer, aterosclerose, diabetes, artrite e doenças do coração. Estudos têm demonstrado que o consumo de substâncias antioxidantes na dieta diária podem prevenir estes processos oxidativos que provocam o envelhecimento precoce do organismo. Nas últimas décadas tem se destacado o interesse em encontrar antioxidantes naturais para o emprego em produtos alimentícios ou farmacêuticos, com a finalidade de substituir antioxidantes sintéticos, os quais apresentam restrições devido ao seu potencial tóxico. Nesse trabalho, são comparados os resultados de medidas da capacidade antirradicalar de vários derivados fenólicos incluindo produtos naturais obtidos com os ensaios utilizando o radical estável DPPH&bull; e o cátion radical ABTS&bull;+, que apresentam vantagens em relação à simplicidade do método analítico e facilidade na coleta de dados, além da reprodutibilidade dos resultados. Além disso, desenvolveu-se um ensaio com DPPH&bull; para avaliar a capacidade antirradicalar de compostos fenólicos em meio ácido, hidroalcoólico e tamponado, para possibilitar a obtenção de valores da capacidade antirradicalar de flavonoides e compostos análogos em meio aquoso em diferentes estados de ionização. Também, foi utilizado o ensaio quimiluminescente com luminol/hemina/H2O2, desenvolvido pelo nosso grupo de pesquisa, para a determinação da capacidade antirradicalar de extratos, fases e frações de Baccharis regnelli e proposto o novo parâmetro \"Porcentagem de Trolox\" para expressar adequadamente esta capacidade em misturas complexas. A sensibilidade do ensaio luminol comprovou ser maior que a de outros métodos e adequado para medir a capacidade antirradicalar de misturas complexas de produtos naturais, auxiliando no isolamento de novas substâncias com atividade antirradicalar. / Living organisms are exposed to the oxidative action of reactive oxygen species (ROS), causing a series of degenerative diseases such as cancer, atherosclerosis, diabetes, arthritis and heart disease. Studies have shown that consumption of antioxidant substances in the daily diet can prevent these oxidative processes that cause premature aging of the organism. Much attention has been paid in the last decades on the discovery of new natural antioxidants for its use in food or pharmaceutical industry, with the aim of replace synthetic antioxidants, which have restrictions due to their toxic potential. In this study, we compared the results from antiradical capacity determinations of several phenolic derivatives including natural products obtained by two different assays. One of them utilizes the stable radical DPPH&bull; and the other the radical cation ABTS&bull;+ as reagents and both have the advantage of a simple analytical method and ease in data collection as well as high data reproducibility. Furthermore, we have developed a method with DPPH&bull; for the evaluation of the antirradicalar capacity of phenolic compounds in acid and buffered hydroalcoholic media, in order to facilitate the determination of the antiradical capacity of flavonoids and similar compounds in aqueous ambient and to allow differentiation between the capacity of different ionization states of these derivatives. Finally the chemiluminescent luminol/hemin/H2O2 assay, developed by our research group, has been utilized for the determination of the antiradical capacity of extracts, phases and fractions of Baccharis regnelli and the new parameter \"Trolox Percentage\" is being proposed to adequately express the antiradical capacity of complex mixtures. The sensibility of the luminol assay has been found to be higher than that of other methods and is shown to be suitable for the determination of antiradical activity parameters of complex natural product mixtures, contributing to the isolation of new substances with antiradical activity.

The sigma-1 receptor, although originally classified as an opioid receptor is now thought of as distinct receptor class, sharing no homology with any other known mammalian protein. The receptor has been implicated with a number of diseases including cancer and depression. Modulation of the receptors activity with agonists has potential antidepressant activity whereas antagonists lead to death of cancer cells. Using radioligand binding assays, utilizing the cancer cell line MDA-MB-468, which highly expresses the sigma-1 receptor, a series of novel specific, high affinity, sigma-1 receptor ligands have been characterised. These ligands differed from any previous sigma- 1 receptor ligand in that they are very simple ammonium salts, containing a single nitrogen atom and either straight or branched carbon chains. The binding studies revealed that the straight-chain ammonium salts gave nH values of 1 whereas the branched-chain ammonium salts had statistically significant lower nH values. The ammonium salts were tested for sigma-1 receptor activity in vitro using ratiometric Fura-2 calcium assays and the MTS cell proliferation assay. Branched-chain ammonium salts appeared to have sigma-1 receptor antagonist like effects on cytoplasmic calcium and cell proliferation, whereas the straight-chain ammonium salts behaved as sigma-1 receptor agonists. Three ammonium salts stood out as potential effective sigma-1 receptor drugs, the straight-chain ammonium salt dipentylammonium, and two branched-chain ammonium salts, bis(2-ethylhexyl)ammonium and triisopentylammonium. The ammonium salts were then tested in vivo. Dipentylammonium showed significant antidepressant properties when tested in behavioural models for depression and bis(2-ethylhexyl)ammonium and triisopentylammonium were able to significantly inhibit the growth of tumours implanted in mice. Finally I looked at the coupling of the sigma-1 receptor with G-proteins and show that sigma-1 receptor antagonists dose dependently reduce G-protein activity and inhibition of G-proteins enhanced the sigma-1 antagonists' effects of calcium signalling.

Cells have lesion bypass DNA polymerases (DNAPs), often in the Y-Family, which synthesize passed DNA damage. One class of Y-Family DNAPs includes hDNAP k, EcDNAP IV and SsDbh, which insert accurately opposite N2-dG adducts, including BP-N2-dG formed from benzo[a]pyrene (BP). Another class includes hDNAP h, EcDNAP V and SsDpo4, which insert accurately opposite UV-damage. For correct Watson-Crick pairing between BP-N2-dG and dCTP, the BP moiety must be in the minor groove. On the minor groove side of the active site, k/IV/Dbh-class DNAPs have large openings that accommodate the BP moiety. Primer extension assays with purified proteins show that DNAP IV correctly inserts dCTP opposite BP more than 10-fold faster than it mis-inserts dATP, dGTP, or dTTP. In contrast, h/V/Dpo4-class DNAPs have small active site openings, which cannot accommodate BP and lead to a distorted structure and increased mutagenesis; e.g., Dpo4 has dGTP and dATP insertion rates that are 10-fold greater than those of dCTP. The opening in Dpo4 is plugged and bulky, whereas DNAP IV has a relatively spacious cavity. Consistent with this model, mutants of Dpo4 with a larger opening insert up to 10-fold more accurately opposite BP-N2-dG. Near the active site, Dpo4 has a single non-covalent bridge (NCB) between the little finger domain and the thumb-palm-fingers domain. DNAP IV and Dbh have a second, distal NCB that is 8 angstroms away from the active site towards the 3' end of the template DNA. Dpo4 becomes nearly 5-fold more accurate when mutated to carry a distal NCB, suggesting that NCB's also help control mutagenesis. Lastly, the active site of Dpo4 has a cavity in the major groove side, which may allow base flipping and dGTP insertion opposite -BP, while k/IV/Dbh-type polymerases do not. When this cavity is plugged in Dpo4 by mutagenesis or the introduction of an N-clasp motif, dGTP rates increase by nearly 20-fold. In conclusion, this data suggests that three structural regions contribute to accurate dCTP insertion opposite BP-N2-dG by k/IV/Dbh-class DNAPs: a large opening on the minor groove side near the active site, a cavity on the major groove side, and the number of non-covalent bridges between the little finger domain and the thumb-palm-fingers domain.

Pureza é um dos principais atributos de qualidade de matérias-primas farmacêuticas, já que a identificação e determinação quantitativa de impurezas podem ajudar a controlar/minimizar o risco de efeitos adversos de medicamentos. O papel dos métodos de doseamento, tanto específicos como não específicos, em caracterizar a qualidade de matérias-primas farmacêuticas, tem sido questionado. Por outro lado, a abordagem do balanço de massas, que quantifica cada impureza orgânica bem como substâncias voláteis e cinzas, e então subtrai a soma destas impurezas de 100%, pode oferecer uma melhor maneira de determinar com exatidão se o fármaco atende aos critérios regulatórios de aceitação e de detectar com confiança mudanças não esperadas na qualidade do fármaco. O objetivo do estudo foi comparar métodos de doseamento compendiais com essa abordagem de balanço de massas na determinação do conteúdo de substância ativa e caracterização da qualidade de matérias-primas farmacêuticas. Os fármacos empregados neste estudo foram o nifedipino, o diazepam, a glibenclamida e a estavudina. A identificação e caracterização dos fármacos foram realizadas por meio de determinação do ponto de fusão e espectroscopia no infravermelho. Para a determinação quantitativa foram empregados os métodos presentes na Farmacopéia Brasileira, United States Pharmacopeia e British Pharmacopeia. O detector de aerossol carregado (CAD) foi acoplado ao sistema de cromatografia à líquido de alta eficiência para comparação das respostas com o detector ultravioleta. Os resultados demonstraram a viabilidade do método indireto, que oferece dados mais precisos que os do método direto, além de favorecer um controle de qualidade mais focado no perfil de impurezas. / Purity is one of the main attributes of quality of bulk drug materials, since the identification and quantitative determination of impurities can help to avoid or at least control/minimize the risk of their contribution to the side effects profile of drug materials. The role of assay methods, either specific or non-specific, in characterizing the quality of bulk drug materials, has been questioned. On the other hand, the mass balance approach, which quantifies every organic impurity as well as volatile substances and ashes, and then subtracts the sum of these impurities from 100%, can provide a better way to accurately determine if the drug substance meets the regulatory acceptance criteria and to reliably detect unexpected changes in the quality of the drug substance. The objective of this study was to compare compendial assay methods with a mass balance approach in the determination of the active ingredient content and characterization of the quality of bulk drug materials. The identification and characterization of the drugs were accomplished through determination of melting point and infrared spectroscopy. The methods from the Farmacopeia Brasileira, United States Pharmacopeia and British Pharmacopoeia were used for the quantitative determination of the drugs. The drug related impurities were determined by high performance liquid chromatography (HPLC) equipped with an ultraviolet (UV) detector and charged aerossol detector (CAD) in tandem. The results demonstrated the feasibility of the indirect method, which offers more precise data than those from the direct method, besides it enables the quality control to be focused on the impurity profile.