Elucidação dos mecanismos de ação do monoterpeno β-mirceno sobre as úlceras pépticas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Palatabilizantes em dietas de leitões recém-desmamados

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação da atividade antibacteriana de espécies vegetais utilizadas em doenças do trato digestório: Baccharis trimera (LESS.) DC. E Casearia sylvestris Swartz

Baccharis trimera (Less.) DC. Asteraceae e Casearia sylvestris Swartz Salicaceae são plantas nativas do Brasil e de uso tradicional em doenças do trato digestório. Seus extratos e substâncias purificadas apresentaram diversas atividades farmacológicas (ex.antiulcerogênica, antimicrobiana) e baixa toxicidade. O Helicobacter pylori (bacilo gram-negativo) coloniza o estômago humano, associada ao maior risco de incidência de várias doenças (úlceras pépticas, linfomas e adenocarcinomas gástricos). Com o objetivo de avaliar a atividade antibacteriana de diferentes extratos, frações e substâncias de ambas as plantas medicinais, extratos de partes aéreas de B. trimera e de folhas de C. sylvestris foram preparados utilizando-se técnicas de maceração, obtendo-se o extrato acetato de etila e etanólico de C. sylvestris e acetato de etila, etanólico, etanol 70% e hexânico de B. trimera. Estes foram fracionados e analisados por técnicas cromatográficas. Os extratos e suas frações e substâncias foram submetidos a ensaios para avaliação da atividade antibacteriana para a determinação da concentração inibitória mínima (CIM). O método utilizado para os ensaios foi a diluição em microplacas usando as bactérias Helicobacter pylori ATCC 43504, Staphylococcus aureus ATCC 25923 e Escherichia coli ATCC 25922. A partir do fracionamento do extrato acetato de etila de B. trimera e do extrato etanólico de C. sylvestris foram obtidas oito frações distintas do EAcBt e a fração de diterpenos do EEtCs. A análise em CCD demonstrou a presença de casearina X, B e caseargrewiina F na fração de diterpenos (EFSCs2). Os extratos da B. trimera EAcBt, EEtBt e EEt70Bt e da C. sylvestris EAcCs e EEtCs apresentaram atividade anti-H. pylori, com valores de CIM de 250, 500, 500, 125 e 750 g/mL, respectivamente... (Resumo completo, clicar acesso eletrônico abaixo)

Avaliação de gastrocitoproteção, mecanismo de ação e comparação do efeito da vitamina E (α-Tocoferol) nas formas natural e sintética

The aim of this study was to verify if α-tocopherol, the main substance of Vitamin E and also the one with the major antioxidant propriety, could offer citoprotection to a stomach damaged by alcohol. There are many forms of α-tocopherol, two forms of them were evaluated; d-l-α-tocopherol, the synthetic form and d-α-tocopherol, the natural form of α-tocopherol. Three experiments were made, all of them having absolute ethanol as the lesion agent, but the period and the doses changed in each of them. In the first two experiments, each group of animals received a different form of α-tocopherol and in the third experiment, they’ve received α-tocopherol p.o. for the period of seven days before the lesion agent was administrated. Moreover, immunohistochemistry assays were made from the stomachs samples of the third experiment to verify possible mechanisms involving nitric oxide and 2-cyclooxygenase. Satisfactory results of citoprotection have been obtained when the two forms were administered in the period of one week at doses of 100 mg/kg for synthetic form and 150 mg/kg for natural type. Nevertheless, the two forms didn’t differ statistically in their effectiveness against ethanol. The immunohistochemistry assays showed an increase of the levels of NO and COX2 in relation with the negative control, although there was no correlation between this increase and the gastroprotective effect. In conclusion, α-tocopherol has gastroprotection effect in some doses, but apparently there is no such a thing like the better the dose, the better the effect; that citoprotection don’t have a relationship with NO neither with COX2; the natural and the synthetic form don’t differ in their gastroprotection effect. More studies must be done looking forward an effective dose and also to understand the mechanisms underlay the citoprotection of α-tocopherol in the stomach

Estudo da motilidade gástrica em ratas prenhes diabéticas e não diabéticas

Several hormonal and physiological changes that occur during pregnancy directly affect gastrointestinal motility (GI), however, very little is known about the relationship between the electrical and mechanical activities of the stomach and its implications. The aim of this study was to compare the female sex hormones, with profiles of gastrointestinal motility using AC biosusceptometry (BAC) in pregnant rats. Seven female Wistar rats (weighing 250-350 g) were used and all procedures were approved by the local Ethics Committee of animal. Laparotomy was performed on anesthetized rats and a magnetic marker (3.5 mm in diameter and 3.0 mm height) was implanted in the distal stomach. After 10 days of recuperation, the mice were put to mate until confirmation of pregnancy. Fed animals were anesthetized (mg pentobarbital 30 / kg) and kept supine for recording the signal with a sensor 30 min BAC placed on the abdominal surface on days 0, 7, 14 and 20 of gestation. Statistical analysis was performed by Student's t test statistical Newman-Keuls and a P value of .05 was considered statistically significant. The frequency of contraction of the stomach was 74 mHz ± 3, 67 ± 7 mHz, 59 mHz ± 6 (p <0.05 vs day -1) and 71 ± 5 mHz on days -0, -7, -14, and -20, respectively. The values of 44 ± 15 pg / mL and 31 ± 9 pg / ml 25 ± 6 pg / ml, 22 ± 9 pg / ml on days -0, -7, -14 and -20, respectively, obtained by 17ß- estradiol were not statistically significant. The values of progesterone were 13 ± 6 pg / ml at 54 ± 15 pg / ml, 127 ± 42 pg / ml (p <0.05 vs day-1), 22 ± 13 pg / mL on day -0, - 7, -14 and -20, respectively. A linear correlation (Pearson's test) between the lower frequency gastric and increased levels of progesterone was 80% (p <0.0000001). Until then, the relationship between changes in motility and hormone were not described in detail, but with the work that we were able to demonstrate the high correlation between progesterone concentration ...

Síndrome dilatação-vólvulo gástrico em cães

The gastric dilatation- volvulus (GDV) is an acute and potentially lethal disease, characterized by increased size of the stomach associated with mesenteric rotation on its axis, which affects mainly large breed dogs and giants with deep and narrow chest. The diagnosis is made from the history, physical examination, clinical signs and radiographic evaluation. It is an emergency that requires immediate therapy and consists on protocols to treat shock, gastric decompression, surgical repositioning of the stomach, gastropexy and intensive post-operative care. Despite the significant progress in the elucidation of pathophysiological events, risk factors and treatment, there was almost no progress in determining the root causes of this disease. A significant advance was recently described in the literature on this topic is the technique of gastropexy laparoscopy. Instruct the owners of the high risk breeds is extremely important to avoid situations in which the severity of the illness make the surgical treatment impracticable and the animal’s condition irreversible

Aspectos Ecológicos da Helmintofauna de Pinguins-de-Magalhães, Spheniscus magellanicus (Aves: Spheniscidae), procedentes do Litoral Norte do Estado de São Paulo

Com o intuito de investigar se estudos parasitológicos podem ser utilizados como ferramenta para a conservação de espécies, principalmente migratórias, este trabalho analisa a helmintofauna de Spheniscus magellanicus através de parâmetros ecológicos populacionais e da comunidade parasitária, relacionando-os com diversos aspectos de vida da espécie hospedeira. O estudo foi realizado com 237 espécimes de S. magellanicus procedentes das praias do litoral Norte de São Paulo (23°46’S, 45°57’O) ao Sul do Rio de Janeiro (23°02’S, 44°13’O). A helmintofauna desta ave incluiu o nematódeo Contracaecum pelagicum (espécie core), encontrado em estômago, o digenético Cardiocephaloides physalis e o cestódeo Tetrabothrius lutzi, ambos (espécies satélites) coletados na porção inicial do intestino delgado. Comparações utilizando o índice de diversidade de Shannon mostraram que a comunidade de parasitas em filhotes durante o período migratório é menos diversa que na estação reprodutiva. Os resultados obtidos permitem inferir que estudos parasitológicos em pingüins, assim como em outros animais migratórios, podem fornecer informações importantes a respeito da espécie durante a época em que permanecem pelágicas, tornando-se uma ferramenta útil na aquisição de informações dificilmente obtidas por outros meios, favorecendo a conservação da espécie

Influência do SNP T3801C CYP1A1 sobre os níveis de danos oxidativos no DNA de células da mucosa gástrica de pacientes infectados pelo H. Pylori

Helicobacter pylori (H. pylori) is a common gastric pathogen that has infected more than 50% of the population of the world and it has been associated with chronic gastritis, gastric ulcers, duodenal ulcer, and gastric cancer. Although, almost all infected people develop gastritis, there is a variety of clinical outcomes, and only a minority (<1%) of infected individuals develop gastric cancer. There are evidences which suggest that the chronic inflammatory reaction caused by the bacterial infection may be involved in the production of reactive oxygen species or reactive nitrogen species. It may lead to DNA damage, which together with the cellular response could lead to gene mutations, chromosomal aberrations characterizing genomic instability that may represent the early step in gastric carcinogenesis. The extent and severity of gastric mucosal inflammation, as well as the clinical outcome of the infection, depend on a number of factors, including the host genetic susceptibility such SNP T3801 CYP1A1, immune response, age at which the infection was acquired, environmental factors, especially dietary and bacterial virulence factors. Due to the risk of developing gastric cancer in humans infected by H. pylori, we used the Comet Assay to investigate the influence of the SNP T3801C CYP1A1 on levels of oxidative DNA damage in gastric epithelial cells. The study was conducted with biopsies from the gastric antrum and corpus of 103 H. pylori-infected patients and 24 uninfected control patients. Genotype of SNP T3801C CYP1A1 was determined by PCR-RFLP and DNA damage levels were measured in gastric mucosal cells from antrum and corpus by the Comet assay. Levels of DNA damage in gastric mucosa cells from antrum and corpus of H. pylori-infected patients with mild, moderate, severe gastritis, and gastric cancer were significantly higher compared to uninfected normal mucosa cells. However, levels... (Complete abstract click electronic access below)

Avaliação da atividade anti -ulcerogênica, antidiarréica e antiinflamatõria de astronium fraxinifolium Schott: Uma espécie medicinal do cerrado

Este trabalho visa o estudo dos efeitos biológicos dos extratos hidroalcóolicos (HDA) obtidos das cascas e folhas de Astronium fraxinifolium (Anacardiaceae), uma espécie medicinal do Cerrado brasileiro. Com base nas indicações populares de uso da espécie no combate a diversos males como a diarréia, cólicas, inflamação e reumatismo e a confirmação pela literatura da atividade gastroprotetora da espécie congênere Astronium urundeuva, foram realizados modelos experimentais in vivo para caracterizar a propriedade anti-úlcera, antidiarrêica e antiinflamatória dos extratos hidroalcóolicos de cascas (A.f.cs) e folhas (A.f.fol) de A. fraxinifolium. A propriedade antiulcerogênica dos A.f.cs e A.f.fol, administrado pela via oral, em diferentes doses (125, 250 e 500 mg/kg) foi avaliada em modelos experimentais in vivo em que os ratos Wistar machos foram confrontados com agentes ulcerogênicos químicos como etanol absoluto e droga antiinflamatória não-esteroidal (DAINE). Os fatores envolvidos na gastroproteção dos extratos foram avaliados através da quantificação de glutationa total do raspado da mucosa, volume do suco gástrico, concentração de íons H+ e pH do suco gástrico. A atuação de fatores protetores da mucosa gástrica como óxido nítrico (NO) e compostos sulfidrílicos (SH) também foram analisados sob efeito de ambos os extratos. A propriedade antidiarrêica dos extratos (500 mg/kg, p.o.) também foi avaliada através da motilidade intestinal, índice de evacuações e acumulo de fluidos intestinais. Ambos os extratos (500 mg/kg, p.o. e 50 mg/kg, i.p.) também foram submetidos a avaliação em dois modelos experimentais (edema da pata induzida por carragenina e teste de formalina) onde as propriedades antiedematogênica e antiinflamatória foram analisadas em roedores. Ambos os extratos foram estudos fitoquimicamente em CLAE-DAE... (Resumo completo, clicar acesso eletrônico abaixo)

Avaliação do efeito da gastrectomia na motilidade e no esvaziamento gástrico em ratos por biosusceptometria de corrente alternada

The study of gastrointestinal tract (GIT) functions is necessary due to the increasing number of pathologies associated with it. Directly influencing the quality of life, the gastrointestinal tract provides a number of parameters that, when analyzed, allow us to describe its dysfunctions. Thus, many techniques can be combined to obtain these properties related to the GIT. However, these techniques are often invasive, require surgery, catheter insertion, or to build a temporal model of these functions, require the sacrifice of animals in a series of data collection. The technique used in this study has the advantage of having a low operating cost, being free of ionizing radiation, non-invasive and is known as biosusceptometry AC (BAC), used to evaluate the properties of the GI tract by monitoring the position and concentration of materials magnetically marked. The sensor consists of two pairs of coils, one reference and one for detection. A fixed base line separates the sensing and reference coils, and also functions as support for the instrumentation. It is also important to note that the detection coils are arranged in a first order (subtraction) gradiometric way. The objective of this study was to analyze the effects of gastrectomy in gastric emptying and gastrointestinal transit time of solid food in rats using a BAC system associated with magnetic markers. To realize this study was constructed a dedicated BAC sensor, built to analyze these GIT properties. Data acquisition was obtained by aligning the magnetic sensor with the stomach and colon of the animal at pre-determined intervals. Thus, when approaching the magnetic material of the sensor, the balance created between the two sides of the sensor is broken. This imbalance can be measured, digitized and acquired. Tracer was used as a ration magnetically marked with ferrite... (Complete abstract click electronic access below)

Avaliação gastroprotetora da epicatequina e verificação de seus mecanismos de ação

The stomach is an exceptional organ, which functions are sterilize food ingested, form the primitive bolus, digest lipids and proteins, and to store food temporarily in the gastrointestinal tract. Its capacity of digesting food without digesting itself is amazing. This fact occurs due to innumerous protective substances adjacent to the gastric mucosa. When aggressive factors overwhelm the protective factors, a lesion in the gastric mucosa is formed. Lesions that reach the lamina propria are called gastric ulcers, which are classified macroscopically as openings on the gastric wall and; microscopically, as a gastric injury characterized with epithelial desquamation, mucosal hemorrhage, glandular damage and eosinophilic infiltration. The current therapy available is effective, although it causes collateral effects, therefore researching new drugs is necessary. This work aim to evaluate the gastroprotective effect of epicatechin against gastric lesions induced by absolute ethanol and non steroidal anti-inflammatory drugs which are the main causes of this disease currently, yet we aim to study the main mechanisms of action responsible for the gastroprotective effect. The results show that epicatechin has a significant macroscopic and microscopic gastroprotective effect against gastric injuries induced by ethanol and indomethacin, acting locally by augmenting gastric mucus secretion and it also acts via antioxidant system by holding total glutathione levels. Epicatechin’s gastroprotective mechanisms depend on the activation of sulfhydryl compounds and doesn’t depend on the NO-synthase enzyme

Infecção por Helmintos em Thoropa taophora (Cycloramphidae) procedentes do Parque Estadual da Ilha Anchieta, Ubatuba, SP

Este estudo analisou a helmintofauna presente no anfíbio anuro Thoropa taophora coletados em uma ilha do Estado de São Paulo. Foram necropsiados 16 hospedeiros e recuperados 226 parasitas, todos nematóides, pertencentes a quatro taxa de helmintos: Physaloptera sp. (Physalopteridae), encontrados no estômago; Rhabdias sp. (Rhabdiasidae), encontrados no pulmão; Oswaldocruzia sp. (Molineidae), no intestino delgado; nematóides da família Cosmocercidae, no intestino delgado e intestino grosso e uma larva de parasita identificado apenas como pertencente à Classe Nematoda. A prevalência total foi 81,25%, de animais parasitados

Jejum no pré-abate de suínos: bem estar animal e qualidade da carne

In the pre-slaughter management of pigs there are stressors, which depending on the duration or severity, are able to alter the quality of meat. One of the factors considered critical to the welfare is the fasting period in the farm. This practice is fundamental and proven relevance in the production chain. Besides the effects on meat quality and welfare of pigs, fasting is among the main factors responsible for the incidence of skin lesions, can significantly influence the incidence of esophagogastric ulcers and is also important to avoid any contamination of carcasses by gastrointestinal contents. When fasting is done right, it has a positive impact on welfare, meat quality and conditions of welfare during the pre-slaughter management of pigs

Avaliação do potencial antioxidante, citotóxico e fotoprotetor de extratos de Hymenaea courbaril L. e Hymenaea stigonocarpa Mart. ex Hayne

Pós-graduação em Biociências - FCLAS

Metais pesados: fonte e ação toxicológica

A contaminação do solo pelo descarte de substâncias tóxicas adquiriu, nos últimos anos, maior atenção da comunidade científica a qual tem alertado a população dos países, em geral, para as conseqüências, em especial, as patologias que podem ocorrer quando estas substâncias adentram nossa cadeia alimentar. Neste trabalho procurou-se apresentar as fontes de contaminação e a toxicidade do cádmio, do chumbo, do mercúrio e do manganês, quando estes se encontram em níveis elevados no solo e nos mananciais superficiais e subterrâneos. Com relação aos três primeiros metais, sua alta dosagem pode provocar, no ser humano, diversos tipos de câncer, lesões no estômago e pulmões, além de alterações importantes nos sistemas imunológico e nervoso central. O manganês, um dos metais mais comuns da crosta terrestre, largamente utilizado pela indústria e disponibilizado, em grandes quantidades no meio ambiente, em doses elevadas pode causar doenças pulmonares e neurológicas.