114 resultados para Lesões cervicais não cariosas


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O adenocarcinoma pancreático é um dos tumores sólidos de pior prognóstico, sendo o tratamento cirúrgico o único potencialmente curativo. Na grande maioria dos pacientes o tumor é diagnosticado em fase avançada, comumente na presença de doença metastática. A introdução de modernos métodos diagnósticos associados ao aperfeiçoamento dos já existentes tem gerado controvérsia quanto à melhor maneira de se estabelecer o diagnóstico e estadiamento do tumor. Da mesma forma, o papel da cirurgia na paliação e aspectos técnicos da ressecção de lesões localizadas estão longe de alcançarem consenso na prática. Método - Revisão da literatura sobre os aspectos controversos relacionados ao tema e um algoritmo para a abordagem dos pacientes com suspeita de tumor de pâncreas são apresentados. Foram utilizados os descritores: “adenocarcinoma” e “pâncreas” para pesquisa no PubMed (www.pubmed.com) e na Bireme (www.bireme.br) e a seguir selecionadas as publicações pertinentes a cada tópico escolhido com atenção especial para metanálises, estudos clínicos controlados, revisões sitemáticas e ainda publicações de grandes centros especializados em doenças pancreáticas. Conclusões - Na suspeita de adenocarcinoma de pâncreas é possível realizar estadiamento muito próximo do real sem a necessidade da exploração cirúrgica sistemática em virtude da disponibilidade na prática de exames modernos e eficientes. Isso permite que paliação menos invasiva seja praticada na maioria dos pacientes com lesões avançadas e incuráveis. Nos em que a cura é possível, a operação deve ser realizada objetivando-se, essencialmente, a remoção da lesão com margens livres e com aceitáveis índices de morbi-mortalidade

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Comparar o desenvolvimento de profissionais e estudantes de enfermagem quanto à realização da técnica de curativo. Metodologia: estudo descritivo com abordagem quantitativa. A amostra foi escolhida através de amostragem por conveniência, tendo participado da pesquisa 14 profissionais de enfermagem, que foram observados no período de março a junho de 2009, e 24 estudantes de enfermagem, regularmente matriculados no último período do Curso de Graduação em Enfermagem da Universidade Federal da Paraíba, os quais foram observados no período de março e maio de 2010. O procedimento de coleta de dados foi efetuado através da observação não participante e preenchimento de um roteiro semi-estruturado, após a aprovação do Comitê de Ética em Pesquisa do Hospital Universitário Lauro Wanderley, sob Protocolo n. 011/09. Resultados: na maioria dos aspectos analisados, os estudantes se sobressaíram aos profissionais, principalmente com relação à lavagem das mãos, orientação do paciente e utilização de movimentos únicos para limpeza da ferida. Conclusão: os profissionais devem melhorar seu conhecimento, buscando atualização nessa área, e os estudantes devem ser supervisionados durante a realização do procedimento

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Compounds derived from fungi has been the subject of many studies in order to broaden the knowledge of their bioactive potential. Polysaccharides from Caripia montagnei have been described to possess anti-inflammatory and antioxidant properties. In this study, glucans extracted from Caripia montagnei mushroom were chemically characterized and their effects evaluated at different doses and intervals of treatment. It was also described their action on colonic injury in the model of colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS), and its action on cells of the human colon carcinoma (HT-29). Compounds extracted of C. montagnei contain high level of carbohydrates (96%), low content of phenolic compounds (1.5%) and low contamination with proteins (2.5%). The (FT-IR) and (NMR) analysis showed that polysaccharides from this species of mushroom are composed of α- and β-glucans. The colonic damage was evaluated by macroscopic, histological, biochemical and immunologic analyses. The results showed a reduction of colonic lesions in all groups treated with the glucans of Caripia montagnei (GCM). GCM significantly reduced the levels of IL-6 (50 and 75 mg/kg, p < 0.05), a major inflammatory cytokine. Biochemical analyses showed that such glucans acted on reducing levels of alkaline phosphatase (75 mg/kg, p < 0.01), nitric oxide (p < 0.001), and myeloperoxidase (p < 0.001). These results were confirmed microscopically by the reduction of cellular infiltration. The increase of catalase activity suggest a protective effect of GCM on colonic tissue, confirming their anti-inflammatory potential. GCM displayed cytostatic activity against HT-29 cells, causing accumulation of cells in G1 phase, blocking the cycle cell progression. Those glucans also showed ability to modulate the adhesion of HT-29 cells to Matrigel® and reduced the oxidative stress. The antiproliferative activity against HT-29 cells displayed by GCM (p <0.001) can be attributed to its cytostatic activity and induction of apoptosis by GCM

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The Brazil is the third largest producer of cashew nuts in the world. Despite the social and economic importance of the cashew nut, its production is still carried out artisanally. One of the main problems encountered in the cashew production chain are the conditions under which the roasting of the nut occurs to obtain the kernel from the shell. In the present study was conducted a biomonitoring of the genotoxic and cytotoxicity effects associated with the elements from the cashew nut roasting in João Câmara - RN, semi-arid region of Brazil. To assess the genotoxic was used the bioassay of micronucleus (MN) in Tradescantia pallida. In addition, it was performed a comparative between the Tradescantia pallida and KU-20 and other biomarkers of DNA damage, such as the nucleoplasmic bridges (NBP) and nuclear fragments (NF) were quantified. The levels of particulate matter (PM1.0, PM2.5, PM10) and black carbon (BC) were also measured and the inorganic chemical composition of the PM2.5 collected was determined using X-ray fluorescence spectrometry analysis and the assessment of the cytotoxicity by MTT assay and exclusion method by trypan blue. . For this purpose, were chosen: the Amarelão community where the roasting occurs and the Santa Luzia farm an area without influence of this process. The mean value of PM2.5 (Jan 2124.2 μg/m3; May 1022.2 μg/m3; Sep 1291.9 μg/m3) and BC (Jan 363.6 μg/m3; May 70.0 μg/m3; Sep 69.4 μg/m3) as well as the concentration of the elements Al, Si, P, S, Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Se, Br and Pb obtained at Amarelão was significantly higher than at Santa Luzia farm. The genotoxicity tests with T. pallida indicated a significant increase in the number of MN, NBP and NF and it was found a negative correlation between the frequency of these biomarkers and the rainfall. The concentrations of 200 μg/mL and 400 μg/mL of PM2.5 were cytotoxic to MRC-5 cells. All together, the results indicated genotoxicity and citotoxicity for the community of Amarelão, and the high rates of PM2.5 considered a potential contributor to this effect, mainly by the high presence of transition metals, especially Fe, Ni, Cu, Cr and Zn, these elements have the potential to cause DNA damage. Other nuclear alterations, such as the NPBs and NFs may be used as effective biomarkers of DNA damage in tetrads of Tradescantia pallida. The results of this study enabled the identification of a serious occupational problem. Accordingly, preventative measures and better practices should be adopted to improve both the activity and the quality of life of the population. These measures are of fundamental importance for the sustainable development of this activity.

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Riboflavin is a vitamin very important in aerobic organisms, as a precursor of many coenzymes involved in the electron transporter chain. However, after photosensitization of riboflavin with UV or visible light, it generates reactive oxygen species (ROS), which can oxidize the DNA. The repair of oxidative lesions on DNA occurs through the base excision repair pathway (BER), where APE1 endonuclease plays a central role. On the other hand, the nucleotide excision repair pathway (NER) repairs helix-distorting lesions. Recently, it was described the participation of NERproteins in the repair of oxidative damage and in stimulation of repair function fromAPE1. The aim of this research was to evaluate the cytotoxic effects of photosensitized riboflavin (RF*) in cells proficient and deficient in NER, correlating with APE1 expression. For this propose, the cells were treated with RF* and it was performed the cell viability assay, extraction of whole proteins, cells fractionation, immunoblotting, indirect immunofluorescence and analysis of polymorphisms of BER gens. The results evidenced that cells deficient in XPA and CSB proteins were more sensitive to RF*. However, XPC-deficient cells presented similar resistance to MRC5- SV cells, which is proficient in NER. These results indicate that XPA and CSB proteins have an important role on repair of oxidative lesions induced by RF*. Additionally, it was evidenced that single nucleotide polymorphisms (SNPs) in BER enzymes may influence in sensitivity of NER-deficient cell lines. Concerning the APE1 expression, the results showed that expression of this protein after treatment with RF* only changed in XPC-deficient cells. Though, it was observed that APE1 is recruited and is bound to chromatin in MRC5-SV and XPA cells after treatment with RF*. The results also showed the induction of DNA damage after treatment with RF*, through the analysis of-H2AX, since the treatment promoted an increase of endogenous levels of this phosphorylated protein, which acts signaling double strand-break on DNA. On the other hand, in XPC-deficient cells, regardless of resistance of RF*, the endogenous levels of APE1 are extremely reduced when compared with other cell lines and APE1 is not bound to chromatin after treatment with RF*. These results conclude that RF* was able to induce cell death in NERdeficient cells, where XPA and CSB cells were more sensitive when compared with MRC5-SV and XPC-deficient cells. This last result is potentially very interesting, since XPC-deficient cell line presents low levels of APE1. Additionally, the results evidenced that APE1 protein can be involved in the repair of oxidative damage induced by RF*, because APE1 is recruited and bound strongly to chromatin after treatment.

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Toxoplasmosis, provoked by the intracellular parasite Toxoplasma gondii, is one of the most prevalent parasitoses in the world. In humans, transmission occurs by three evolutionary forms of the parasite: oocysts, tissue cysts and tachyzoites. Wild and domestic felines are definitive hosts. The ocular form of toxoplasmosis can be of congenital origin with early or late clinical manifestations, or acquired after birth. T. gondii is considered the main culprit for most cases of infectious uveitis. This study aimed at assessing ocular toxoplasmosis, relating it to factors associated to the patient s lifestyle and describing the epidemic-serological and clinical profile of affected individuals. A cross-sectional study was conducted with a population of 159 patients. Univariate analysis (odds ratio) was used to evaluate the data, with a confidence interval of 95% and p-value < 0.05. A prevalence of 4% of ocular toxoplasmosis was observed in the population of patients treated at an ophthalmological clinic. Of patients directly examined by immunoenzymatic assay (MEIA-AxSYM®- Microparticle Enzyme Immune Assay), considering only uveitis, a frequency of anti-T. gondii of 73%, most of whom exhibited titulation between 40-99 UI IgG/mL. With respect to location of ocular lesions, bilaterality was observed in 57% of patients assessed by the ophthalmoscopy technique. When compared with the results of an active search of medical records, a similarity in ocular toxoplasmosis (74%) and bilateral lesion location (55%) was observed. Type I lesion was the most frequent type observed, with intraocular disposition in the macula. An epidemiological survey revealed that direct contact with cats; consuming raw or poorly cooked meat and direct contact with the soil were significantly associated with greater likelihood of acquiring ocular toxoplasmosis. Sample characterization in relation to age range was significant for patients between 31 and 40 years [χ², chi-square test (p = 0.04)], but population traits such as schooling, sanitary district, and monthly income were not significant. Results confirm that ocular toxoplasmosis is widely distributed in the metropolitan area of Natal, Brazil, with significant prevalence of ocular lesions provoked by T.gondii. It is suggested that sanitary authorities exert greater control in order to minimize the risk of toxoplasmic infection, mainly in pregnant women.

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Reactive oxygen species (ROS) are continuously generated and can be derived from cellular metabolism or induced by exogenous factors, in addition, have the capacity to damage molecules like DNA and proteins. BER is considered the main route of DNA damage oxidative repair, however, several studies have demonstrated the importance of the proteins participation of other ways to correct these injuries. NER enzymes deficiency, such as CSB and XPC, acting in the damage recognition step in the two subways this system influences the effectiveness of oxidative damage repair. However, the mechanisms by which cells deficient in these enzymes respond to oxidative stress and its consequences still need to be better understood. Thus, the aim of this study was to perform a proteomic analysis of cell lines proficient and deficient in NER, exposed to oxidative stress, in order to identify proteins involved, directly or not, in response to oxidative stress and DNA repair. For this, three strains of human fibroblasts, MRC5-SV, CS1AN (CSBdeficient) and XP4PA (XPC-deficient) were treated with photosensitized riboflavin and then carried out the differentially expressed proteins identification by mass spectrometry. From the results, it was observed in MRC5-SV increase expression in most of the proteins involved in cellular defense, an expected response to a normal cell line subjected to stress. CS1AN showed a response disjointed, it is not possible to establish many interactions between the proteins identified, may be one explanation for their sensitivity to treatment with riboflavin and other oxidants and increased cell death probably by induction of pro-apoptotic pathways. Already XP4PA showed higher expression of apoptosis-blocking proteins, as there was inhibition or reduced expression of others involved with the activation of this process, suggesting the activation of an anti-apoptotic mechanism in this lineage, which may help explain the high susceptibility to develop cancers in XPC individuals. These results also contribute to elucidate action mechanisms of NER in oxidative damage and the understanding of important routes in the oxidative stress correlation, repair and malignant tumors formation

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This study assessed the level of knowledge, attitude and practice of Pap smear and human papillomavirus (HPV), in addition to analyzing the prevalence of genital HPV infection, Herpes Simplex Type 2 (HSV-2) and Chlamydia trachomatis in teenagers. The study consisted of two approaches, one based only on interviews conducted with adolescents enrolled in public schools or in public health facilities in the city of Natal. The other approach involved only a group of 132 adolescents enrolled among those admitted to two health units in Natal-RN. This second group of participants two specimens were collected for laboratory analysis: one was directed to prepare the blade for the Pap test, and other processed for DNA extraction for molecular analysis, focusing on the detection of HPV, HSV-2 and C . trachomatis. The presence of DNA of the three pathogens was investigated by the technique of polymerase chain reaction (PCR). The presence of each of the three pathogens was analyzed in terms of socio-demographic characteristics, as well as sexual and reproductive activity to identify risk factors for infection and development of lesions of the uterine cervix. The results show that the adolescents in this study had levels of knowledge and attitude very low, both in relation to cytology to HPV as though they have made a reasonable percentage of adequate practice exam and prevention of HPV infection. The overall prevalence of HPV infection was 54.5% and 48.2% in adolescents with normal cytology and 86.4% in those with abnormal cytology. We observed a higher proportion of cases of infection in the age group of 18 to 21. The prevalence of HPV infection was slightly higher among pregnant teenagers. The overall prevalence of HSV-2 infection was 13.6% and 11.8% in women with normal cytology and 22.7% in those with abnormal cytology. A higher proportion of cases of infection was found in the age group from 14 to 17, with a slightly higher prevalence among pregnant women. The C. trachomatis was found with an overall prevalence of 19.7% and 21.8% in adolescents with normal cytology and 9.1% in those with abnormal cytology. The prevailing rate was highest in the age group 18 to 21 years and in nonpregnant

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Herpes simplex is a virus that can be transmitted sexually and is potentially associated with vertical transmission. This study evaluated the prevalence of genital infection by herpes simplex virus (HSV) types 1 and 2 in pregnant and nonpregnant care in the city of Natal / RN, including a total of 222 women, 92 pregnant and 130 nonpregnant. The participants answered a questionnaire to obtain data and socio-demographic characteristics, as well as potential risk factors for sexually transmitted diseases. After the interview, we collected two cervical specimens, one for the Pap test and the other for DNA extraction and analyzed by polymerase chain reaction (PCR) to detect both virus serotypes. Then the women underwent a clinical examination by colposcopy. For statistical analysis, we used the chi-square and logistic regression by SSPS 17.0 Statistic. Most women were up to 30 years of age, nonwhite ethnicity, married, elementary education, family income below the poverty level; initiated sexual activity with age up to 18 years; had more than one sexual partner lifelong and was not pregnant, but has had at least one child. The HSV-1 showed a prevalence of 26.1% among pregnant women and 30.0% in non-pregnant women. While HSV-2 prevalence was found with 10.9% and 19.2% in pregnant and nonpregnant women, respectively. The largest proportion of morphological changes of the uterine cervix was detected among nonpregnant women, both in cytology and in colposcopy. The women were nonwhite ethnicity, married, became pregnant aged less than or equal to 18 years and who had one to two pregnancies had a lower risk of acquiring genital HSV infection. There was a high prevalence of genital HSV infection, HSV-1 is more prevalent than HSV-2. No association was found between morphological changes of the uterine cervix and the presence of the virus in pregnant and nonpregnant women, nor between genital HSV infection and the classic risk factors for sexually transmitted diseases

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The genital HPV infection is very common between men and women worldwide, affecting particularly young women, constituting a serious public health problem in less developed regions, favored by the poor living conditions of population. The cytology and colposcopy have notorious importance in the diagnosis of precursor lesions of cervical cancer and therefore its prevention. However, even with such diagnostic tools, the number of women who develop cervical cancer is still high. This study aims to assess the prevalence of genital tract infection by HPV in pregnant and nonpregnant women, evaluating the profile of the immune response presented by the women of these two groups in order to establish correlations among profile of immune response, presence of virus and occurrence of lesions of the uterine cervix. We analyzed specimens obtained from the cervix of 221 patients, 91 pregnant and 130 non-pregnant, aged 14-72 years. The women were subjected to colposcopic and cytologic evaluation detect possible changes in the cervix and then samples were collected in order to perform HPV detection by PCR and real-time PCR for detection of mRNA of pro-inflammatory and anti-inflammatory cytokines. In the present study, the overall prevalence of HPV genital infection was 28.1%; of which 31.9% were pregnant patients and 25.4% in non-pregnant women. Young women under 30 years and those with low educational level education showed a higher risk of HPV infection. Colposcopy showed better correlation with detection of HPV DNA by PCR, when compared to cytology. Generally, HPV infected patients, pregnant or not, exhibited reduced mRNA expression of both pro-inflammatory (IFN-γ, TNF-α) and anti-inflammatory (IL -10) cytokines, when compared to patients not infected by HPV. Nonpregnant patients infected presented increase mRNA expression of IL-17 in patients without injury, whereas those with lesion showed higher mRNA expression of TGF-β. Pregnant women without injury infected exhibited increased mRNA expression of TGF-β. There was no difference in HPV prevalence between pregnant and nonpregnant women. There was a reduction of pro-inflammatory cytokines, except IL-17, in all women infected by HPV. Moreover, we observed an increase of TGF-β in HPV-infected women who are pregnant or not. The results suggest that, in women in this study, HPV infection promoted changes in the profile of cytokines necessary for activation of effective immune response, possibly favoring viral persistence

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Genital infection with Chlamydia trachomatis is now recognized as one of the most prevalent sexually transmitted infections (STDs). Despite major advances in laboratory diagnosis techniques, primarily the character of asymptomatic chlamydial infection in both men and in women constitutes the basis for the formation of reservoirs that perpetuate transmission and acquisition of this and other STDs. The asymptomatic in women favors the rise of infection to the upper genital tract, causing injuries that can result in infertility. An examination of population screening for early detection and treatment of asymptomatic infections is the key step in combating this major public health problem. The present study aimed to evaluate the prevalence of infection by C. trachomatis in sexually active women attended the screening program for cervical cancer of the uterus in health facilities in municipalities in different regions of the State of Rio Grande do Norte, and identify factors that may contribute to the spread of this pathogen and its relationship with the lesions of the uterine cervix. It is a cross-sectional study aimed at detecting the presence of genital tract infection by C. trachomatis either in isolated form or in association with human papilloma virus (HPV) infection in asymptomatic women. Were included in this study, a total sample of 1,134 women aged 13-76, mean 34.4 years, from March 2008 to September 2012. Specimens containing exfoliated cells of the epithelium of the uterine cervix were analyzed by examining Pap cytology for the detection of possible injuries, and the polymerase chain reaction (PCR) for detection of plasmid DNA from C. trachomatis and HPV. Infection with C. trachomatis was detected with overall prevalence rate of 8.1% in the isolated form and 2.8% in co-infection with HPV. The infection was detected in 7.4% of women with normal cytology 11.5% of those with atypical cells of undetermined significance (ASC-US) and 16.7% of those with low-grade squamous intraepithelial lesion (LSIL). We observed an association between C. trachomatis and incidence of low-grade squamous intraepithelial lesion (LSIL). The genital tract infection by C. trachomatis alone was associated with education level, ethnicity and parity, revealing that women with higher education, those of non-white ethnicity and those who had three or more pregnancies were more likely to acquire infection. Levels very close to statistical significance were observed for chronological age, age at first sexual intercourse and first pregnancy. There was no association with marital status, number of sexual partners. Co-infection with C. trachomatis and HPV was detected in 2.3% of women with normal cytology, who had 5.1% in ASC-US and 10.4% in those with LSIL. No association was found between infection C. trachomatis and increased risk of HPV infection, but women with simultaneous infection by both pathogens showed greater risk for LSIL. Co-infection was more prevalent among single women, who had in the first sexual intercourse under 18 years and those who had two or more sexual partners over a lifetime

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As doenças inflamatórias intestinais são enfermidades onde a tolerância e homeostase da resposta inflamatória estão comprometidas, gerando lesões teciduais e favorecendo o surgimento de neoplasias. Há dois importantes exemplos de doenças inflamatórias intestinais, a colite ulcerativa, foco do modelo desse estudo, e a doença de Crohn. Os medicamentos utilizados no tratamento dessas doenças desencadeiam diversos efeitos adversos; além disso, em alguns pacientes, eles não são eficazes. Os extratos de algas têm demonstrado várias atividades biológicas, entre elas a atividade anti-inflamatória. Os extratos das algas do gênero Caulerpa foram utilizados em vários estudos, onde modelos inflamatórios foram analisados, entre eles o modelo de colite ulcerativa. A utilização do extrato metanólico da C. mexicana como terapêutica nesse modelo atenuou o quadro clinico desenvolvido pelos animais. Sendo assim, o presente estudo teve como objetivo analisar a ação terapêutica da Caulerpina (CLP), extraída da C. racemosa, no modelo murino de colite ulcerativa. Camundongos C57BL/6 machos foram expostos a uma solução de Dextrana Sulfato de Sódio (DSS) a 3% por sete dias. A partir do primeiro dia de exposição ao DSS os animais foram tratados em dias alternados com a CLP nas doses de 4 e 40 mg/kg e com a dexametasona (3 mg/kg) por via oral. O desenvolvimento da doença foi analisado através do índice de atividade da doença (IAD), que leva em consideração a perda de peso corporal, a consistência e a presença de sangue nas fezes. Após a eutanásia, o cólon foi removido e mensurado, e amostras do tecido colônico foram destinadas a análise histológica e à cultura para dosagem de citocinas. Os níveis de citocinas no sobrenadante da cultura do cólon foram mensurados por ELISA. O tratamento com a CLP (4 mg/kg) desencadeou significativa melhora quanto à perda de peso corporal e ao IAD, e atenuou o encurtamento do cólon em resposta ao DSS. Tal dose foi capaz de reduzir os níveis de citocinas pró-inflamatórias analisadas (TNF-, IFN-, IL-6, IL-17), mas não teve efeito significativo nas citocinas anti-inflamatórias IL-10 e TGF-. O tratamento com a CLP (40 mg/kg) não foi eficaz quanto a perda de peso e ao IAD, além de não ter atenuado a redução do cólon em resposta ao DSS. Essa dose conseguiu reduzir os níveis das citocinas pró-inflamatórias, porém não os níveis de IL-6. O tratamento com a dexametasona obteve melhora discreta quanto à perda de peso corporal e ao IAD, porém não atenuou a redução do cólon em resposta ao DSS. Esse tratamento também conseguiu reduzir todas as citocinas pró-inflamatórias testadas. Deste modo a CLP (4 mg/kg) demonstrou ser uma alternativa promissora no tratamento da colite ulcerativa, em razão dos seus efeitos benéficos sobre parâmetros clínicos, morfológicos e moleculares do modelo em estudo

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The decoction of Brazilian pepper tree barks (Schinus terebinthifolius, Raddi), is used in medicine as wound healing and antiinflamatory. Once extracts from this plant are used for acceleration of scar s process, it is important to study their mutagenic and genotoxic potential. In previous works in our laboratory, it was observed mutagenicity caused by the decoction when in high concentrations. Among the chemical compounds of this plant that could be able to induce mutation, the flavonoids were the only group that was referred to have either an oxidant or antioxidant potential. The flavonoids were isolated, purified and quantified by adsorptive column chromatography under silica gel, bacterial and in vitro genotoxic tests were realized to determine if the flavonoids were the responsible agents for this mutagenicity found. The tests realized with plasmidial DNA were indicative that the flavonoids are probably genotoxic, due to the presence of correlation between increase of the flavonoid concentration and in plasmidial DNA double strand breakage visualized in agarose gel, as well as they were capable to generated abasic sites shown by the in vitro treatment with exonuclease III. The same tests with plasmidial DNA in the presence of copper [10 µM] and of a Tris-HCl pH 7.5 [10 µM] buffer were realized with the isolated flavonoids to determine if there would be or not participation of reactive oxygen species (ROS). The transformation of plasmidial DNA in different bacterial strains proficient and deficient in DNA repair enzymes in the presence or not of a Tris-HCl buffer, suggests that the enzymes that repair oxidative lesions are necessary to repair the lesions generated by the flavonoids and that ROS are generated and are necessary to promote the lesions. Bacterial tests with Escherichia coli strains of the CC collection (deficient or not for DNA repair enzymes), showed that the flavonoids are able to increase the frequency of mutations, mainly in strains mutated in repair enzymes (MutM, MutY-glicosylases and double mutant), suggesting that these agents are responsible for the enhancement in the mutation rate. In order to determine the mutation spectrum caused by the flavonoids of the Brazilian pepper tree stem bark, plasmidial DNA previously treated with the flavonoids were transformed in bacterial strains deficient and proficient in the DNA repair enzymes, followed by a blue-white selection with X-gal, DNA amplification by PCR and sequencing the positive mutant clones. Analysis of the mutants obtained from strains CC104, CC104mutM, CC104mutY, CC104mutMmutY, BW9101, BW9109 indicated a predominance of some mutations like G:C to C:G that can be correlated with the origin of 8-oxoG, due to oxidative lesions caused by the flavonoids. So it can concluded that the flavonoid isolated or in fractions enriched on them are genotoxic and mutagenic, and their mutations are predominantly oxidative, mediated by ROS, and the lesions are recognized by the BER system. In this way it is proposed that the flavonoids can act in two different ways to generate the DNA lesion: 1. in a Fenton-like reaction, when the flavonoid are in the presence of metal ions and that together with the water generate ROS that promotes the DNA lesions; 2. in another way the lesions can be generated by the formation of ROS due to the internal chemical structure of the flavonoid molecule due to the quantity and location of hydroxyl groups, and so producing the DNA lesions, those lesions can be directly (suggested by the in vitro experiments) or indirectly done (supported by the experiments using the CC bacterial strains)

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Objetivo: analisar o estado da arte dos aspectos diagnósticos, periciais e jurisprudenciais das LER/DORT (Lesões por Esforços Repetitivos / Distúrbios Osteomusculares Relacionados ao Trabalho) no Brasil. Materiais e Método: trata-se de pesquisa descritiva, de natureza qualitativa, com formato documental, utilizando-se a técnica de análise de conteúdo. A avaliação evolutiva da legislação previdenciária relacionada as LER/DORT foi realizada através da pesquisa no banco de dados disponibilizado pelo Governo Federal e mediante a consulta ao DATAPREV/Sislex. A avaliação dos aspectos diagnósticos foi instrumentalizada através, principalmente, de artigos científicos publicados entre 2003 e 2008, nas línguas portuguesa, inglesa, espanhola e francesa, relacionados com os métodos de diagnósticos complementares das LER-DORT (ressonância magnética, tomografia computadorizada, ultrassonografia e eletroneuromiografia). As jurisprudências foram obtidas através da busca dos julgados sobre o tema, entre 2003 e 2008, pertencentes ao Supremo Tribunal Federal, Superior Tribunal de Justiça, Tribunais Regionais Federais, Tribunal Superior do Trabalho e Tribunais Regionais do Trabalho. Resultados: foram identificados 48 artigos abordando os aspectos diagnósticos das LER-DORT, observando-se que os exames por ressonância magnética, ultrassonografia e eletromiografia demonstraram ser mais efetivos, dentro das suas especificidades, para a complementação do exame clínico de patologias relacionadas às LER-DORT. A análise das 123 jurisprudências selecionadas demonstrou, de forma geral, que as LER-DORT equiparam-se ao acidente de trabalho, devendo apresentar nexo de causalidade (atestado através de laudo médico-pericial) e, ainda, ensejam a ação por danos morais, a qual, devido à EC nº 45 passou a ser competência da Justiça do Trabalho. O Estado da arte dos aspectos periciais encontra-se representado pela vigência da Instrução Normativa n. 98/2003, a qual traz como aspecto fundamental a determinação de novos parâmetros a serem considerados na definição de um quadro de LER-DORT, dispondo, ainda, sobre a conduta ética que deve ser adotada pelo médico perito, bem como chama a atenção para a necessidade dessas doenças do trabalho serem comunicadas às autoridadades competentes, através da emissão da Comunicação de Acidente de Trabalho (CAT). Conclusão: as LER-DORT representam, hoje, um problema de importante impacto, não apenas previdenciário, mas também econômico em diversos países, nos quais o Brasil encontra-se inserido. Estudos sobre o estado da arte relacionados às LER-DORT são fundamentais para auxiliar na construção de um modelo crítico e consciente que colabore com a garantia de sustentabilidade do sistema previdenciário no Brasil

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The objective of this clinical study was to evaluate the effectiveness of the toothbrushing with and without fluoride and the daily fluoride rinse (NaF 0.05%) on produced white spot, in vivo. This was a clinical study, controlled, randomized and triple blind. Thirty patients were selected for orthodontics reasons from Orthodontics Specialization Course at the Brazilian Dental Association - Section of Rio Grande do Norte. In this study it was used 4 bicuspid upper and lower. They had orthodontic reason for extractions, in 35 days, at least. The sample had one hundred and twenty teeth that received orthodontic bands. The bands were fixed with polycarboxylate cement, and there was a space standardized between bands and one surface of teeth. The four bicuspid of each patients were randomized and nominated as A, B, C and D. These nominations determinated the sequence of the extractions and what was done in each tooth. All the patients had been submitted to the toothbrushing with or without fluoride for 35 days. After this period, the A tooth of each patient was extracted to serve as control. The others teeth (B, C and D) were extracted one by each week. The entire sample was analyzed through the clinical examination and by laser fluorescence (DIAGNOdent®) in three different times: before orthodontic bands, 28 days after fixed and then removed the bands and, the last one, 07 days after one of the three treatments (toothbrushing with or without fluoride, tooth paste with fluoride and mouth rinse with fluoride). At the beginning all groups (A, B, C and D) had the same conditions, no significant difference was found. The same situation was found in a clinical examination. The results of the DIAGNOdent® for the groups that used tooth paste without fluoride, with fluoride and mouth rinse with fluoride, after 28 days, there was no significant difference. Clinically, the white spot was formed in all teeth after 28 days. When it was compared the three treated groups, the group without fluoride in tooth paste had worst result than the others groups. But there was no significant association between the number of active and inactive white spots and the type of treatment that the teeth had received. The demineralization of the enamel surface, under the orthodontic bands, it happened in a few weeks. The exposition of the white spots in oral environmental resulted in an improvement, but it was not enough to return to the values from the base line, either for the toothbrushing and/or the use of fluorite mouth rinse. Mouth rinse and toothpaste with fluoride have showed to reduce the incidence of demineralization in the enamel, but none seems to be superior to another one in an in vivo study