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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Structural Characterization of Potential Cancer Biomarker Proteins

January 2012 (has links)
abstract: Cancer claims hundreds of thousands of lives every year in US alone. Finding ways for early detection of cancer onset is crucial for better management and treatment of cancer. Thus, biomarkers especially protein biomarkers, being the functional units which reflect dynamic physiological changes, need to be discovered. Though important, there are only a few approved protein cancer biomarkers till date. To accelerate this process, fast, comprehensive and affordable assays are required which can be applied to large population studies. For this, these assays should be able to comprehensively characterize and explore the molecular diversity of nominally "single" proteins across populations. This information is usually unavailable with commonly used immunoassays such as ELISA (enzyme linked immunosorbent assay) which either ignore protein microheterogeneity, or are confounded by it. To this end, mass spectrometric immuno assays (MSIA) for three different human plasma proteins have been developed. These proteins viz. IGF-1, hemopexin and tetranectin have been found in reported literature to show correlations with many diseases along with several carcinomas. Developed assays were used to extract entire proteins from plasma samples and subsequently analyzed on mass spectrometric platforms. Matrix assisted laser desorption ionization (MALDI) and electrospray ionization (ESI) mass spectrometric techniques where used due to their availability and suitability for the analysis. This resulted in visibility of different structural forms of these proteins showing their structural micro-heterogeneity which is invisible to commonly used immunoassays. These assays are fast, comprehensive and can be applied in large sample studies to analyze proteins for biomarker discovery. / Dissertation/Thesis / M.S. Biochemistry 2012
372

Non-vitamin K dependent oral anticoagulants (NOACs) controls

Persson, Anna January 2018 (has links)
In recent years non-vitamin K dependent oral anticoagulants (NOACs) have started to replace warfarin for treatment and prevention of deep venous thrombosis (DVT), pulmonary embolism (PE) and stroke in patients with and without atrial fibrillation. There is a need for a simple and rapid method to detect the presence of these drugs in patient plasma. To meet these new demands, MediRox is developing a screening assay based on a novel prothrombin time (PT) method for rapid detection of NOACs in plasma. The assay is semi-quantitative and by dividing the International Normalised Index (INR) from a NOAC sensitive PT method with the INR from a NOAC insensitive PT method, NOAC containing samples be detected while plasma from normal donors and with warfarin are excluded.   The purpose of this project is to develop prototypes of assay quality controls for detection of NOACs in plasma.   The results show that the method used for the NOAC control prototypes is applicable and the PT ratio is comparable to patient samples for the low, medium and high concentrations of NOAC. The effect of lyophilisation indicates that the PT ratios for the NOAC control prototypes were nearly unaffected by the lyophilisation. The in-use stability at room temperature (20-25oC) for all NOAC control prototypes were at least 24 hours.   The methodology for production needs to be further optimised to increase the commutability to patient samples with very high concentrations of NOAC. The data indicates that the effect of lyophilisation is minimal and the stability of the NOAC control prototypes are satisfying, which is promising for future product development of NOAC controls.
373

Stability of protein-based drugs : Herceptin® : a case study

Shropshire, Ian Michael January 2016 (has links)
There is a lack of stability data for in-use parenteral drugs. Manufacturers state a shelf-life of 24 hours for infusions based on microbiological contamination. The lack of data is of particular significance with protein-based drugs where action is determined by their complex structure. A range of techniques are required to assess stability, including biological assessment to support other data. There has been an increase in published data but often the few studies that address in-use stability are incomplete as they do not employ biological assessment to assess potency. Trastuzumab is an antibody-based drug used to treat cancers where the Epidermal Growth Factor Receptor 2 (HER2) is over expressed or over abundant on the cell surface. Trastuzumab infusions have been assigned by the manufacturer to be stable for 24 hours at temperatures not exceeding 30 oC. If stability is shown beyond this point it would enable extended storage and administration. To this end, methods were selected and developed with biological assessment central to the approach to assess clinically relevant infusion concentrations (0.5 mg/mL and 6.0 mg/mL) and a sub-clinical infusion concentration (0.1 mg/mL). This may enhance instability and provide opportunity to study degradation. A Cell Counting Kit CCK8 (Sigma Aldrich) was ultimately adopted as a basis for a colorimetric assay to assess cell viability. Attenuated Total Reflectance Infra-Red Spectroscopy and Size Exclusion Chromatography methods were developed to evaluate secondary structure and aggregation respectively. These methods were applied to a shelf-life study (43 days) as a collaboration with Quality Control North West (NHS) and Clatterbridge Centre for Oncology NHS Foundation Trust, Clatterbridge Hospital. There was no evidence of degradation and no loss efficacy for clinically relevant infusions (0.5 mg/mL and 6.0 mg/mL) over 43 days, whilst the sub-clinical infusions (0.1 mg/mL) developed particles after 7 days of storage between 2 oC and 8 oC. Furthermore, evidence of stability at day 119 gave increased confidence for the data from earlier time points. This work assisted in the shelf-life being recommended to be extended to 28 days for Trastuzumab stored in polyolefin IV bags at concentrations between 0.5 mg/mL and 6.0 mg/mL with 0.9% saline between 2 oC and 8 oC. However, infusions with concentrations below 0.5 mg/mL were not recommended for storage.
374

Teste do cometa como ferramenta de controle da cadeia do frio / Comet assay as a cold chain control tool

DUARTE, RENATO C. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:26:48Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:22Z (GMT). No. of bitstreams: 0 / Tendo em vista um mercado cada vez mais exigente na qualidade dos alimentos, faz-se necessário o desenvolvimento de processos que atendam às expectativas do consumidor. Dentre os processos existentes, destacam-se a cadeia do frio e a irradiação. A cadeia do frio compreende todas as etapas de conservação do alimento, desde a produção, resfriamento, congelamento, armazenamento, e transporte até o consumidor final. A irradiação, como processo de conservação de alimentos, estende a vida de prateleira, inibe o brotamento e reduz a contaminação por patógenos, entre outros benefícios. É importante a identificação da degradação dos alimentos em função de falhas nos processos a que foram submetidos. O teste do cometa (DNA Comet Assay) é um método de varredura largamente estudado, considerado rápido e de baixo custo, pelo fato de identificar quebras no DNA, é possível considerar sua utilização como mais uma ferramenta no controle de falhas na cadeia do frio que podem degradar e prejudicar os alimentos. Algumas etiquetas e selos usados no controle dos processos do frio não consideram a situação anterior do alimento, indicando falhas a partir do momento em que forem colocadas em contato com o mesmo, já o teste do cometa verifica a degradação ocorrida no alimento até o momento de sua realização podendo ainda, acompanhar o aumento da degradação. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
375

Aplicação do método microbiológico DEFT/APC e do teste do cometa na detecção do tratamento com radiação ionizante de hortaliças minimamente processadas / Application of the microbiological method DEFT/APC and DNA comet assay to detect ionizing radiation processing of minimally processed vegetables

ARAUJO, MICHEL M. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:54:24Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:08:02Z (GMT). No. of bitstreams: 0 / O comércio de vegetais minimamente processados (VMP) tem crescido substancialmente nos últimos anos devido a sua conveniência, frescor e aparente salubridade. No entanto, o processamento mínimo não reduz as populações de microrganismos patogênicos para níveis seguros. A irradiação de alimentos é utilizada para estender a vida de prateleira e inativar patógenos presentes nos alimentos. Seu uso combinado com o processamento mínimo poderia aumentar a segurança e qualidade dos VMP. Dois diferentes métodos de detecção de alimentos irradiados, um biológico, o DEFT/APC, e outro bioquímico, o teste do cometa, foram aplicados a VMP com o objetivo de testar sua aplicabilidade na detecção do tratamento por radiação. O DEFT/APC é um método de varredura microbiológico baseado no uso da técnica de epifluorescência direta em filtro (DEFT) e da contagem padrão em placas (APC). O teste do cometa detecta o dano no DNA devido, por exemplo, a radiação ionizante. Amostras de acelga, agrião, alface, catalônia, couve, escarola, espinafre e repolho do comércio varejista foram irradiadas com 0,5kGy e 1,0kGy utilizando um irradiador de 60Co. O processamento por irradiação garantiu a redução de pelo menos dois ciclos logarítmicos nas populações de microrganismos aeróbios e psicrotróficos. Em geral, com o aumento das doses de radiação, as contagens DEFT se mantiveram similares independentemente do processamento por irradiação, enquanto as contagens APC diminuíram gradualmente. A diferença das duas contagens aumentou gradualmente com o incremento da dose em todas as amostras. Uma diferença entre o valor de DEFT e do APC maior a 2,0 log seria indicativa de que o VMP foi tratado por irradiação. O teste do cometa permitiu distinguir amostras não irradiadas das irradiadas, que mostraram diferentes tipos de cometas decorrentes da fragmentação do DNA. Tanto o método DEFT/APC quanto o teste do cometa foram satisfatoriamente utilizados como métodos de varredura para a detecção do tratamento por irradiação. / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN/CNEN-SP
376

Estudo randomizado, duplamente mascarado, placebo controlado do uso do misoprostol versus placebo para histeroscopia diagnostica em mulheres na pos-menopausa

Costa, Aurelio Antonio Ribeiro da 12 December 2006 (has links)
Orientador: Aarão Mendes Pinto-Neto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-08T02:23:48Z (GMT). No. of bitstreams: 1 Costa_AurelioAntonioRibeiroda_D.pdf: 582824 bytes, checksum: b130d3e6304e9d014c75b64794caae29 (MD5) Previous issue date: 2006 / Resumo: a histeroscopia é um dos procedimentos mais realizados em ginecologia. Muitos ensaios controlados sugerem vantagens no uso prévio de misoprostol para diminuir a resistência da cérvix uterina; entretanto este tipo de estudo ainda é escasso quando se compara o uso do misoprostol prévio à histeroscopia diagnóstica em mulheres na pós-menopausa. avaliar os efeitos intra e pós-operatórios em mulheres na pós-menopausa, submetidas à histeroscopia diagnóstica, sem anestesia, com uso prévio de misoprostol para amadurecimento do colo uterino. Sujeitos e métodos: foi realizado um estudo tipo ensaio clínico, duplamente mascarado, randomizado, em pós-menopausadas que se submeteram à histeroscopia diagnóstica sem anestesia no IMIP e no hospital Barão de Lucena, em Recife, Pernambuco. Foram incluídas 120 pacientes alocadas aleatoriamente em dois grupos, sendo 60 com uso de 200µg de misoprostol via vaginal e 60 com uso de 200µg de placebo. Foram estudadas as seguintes variáveis: tempo do procedimento, freqüência e intensidade da dor durante o exame, necessidade de dilatação cervical adicional, efeitos colaterais (sangramento genital, náuseas, vômitos, diarréia, hipertermia) e complicações (perfuração uterina, falso pertuito, laceração cervical, infecções, dor no pós-operatório imediato). Para análise estatística, utilizaram-se os testes de qui-quadrado de associação, testes exato de Fisher e Mann-Whitney para comparação dos grupos, considerando-se significativo um erro alfa menor que 5%. Resultados: os grupos foram semelhantes em relação à média de idade (61,3 e 59,2, p=0,09), paridade (04 e 04, p=0,88), IMC (27 e 27,5, p=0,55) e tempo de menopausa (12,5 versus 9,6, p=0,52), intervalo entre medicação e exame (8,4 e 8,2, p=0,4), meio distensor com CO2 (39% versus 32%, p=0,44) e indicações por mioma, espessamento ou sangramento genital (p=0,52; 0,37; 0,62, respectivamente). O grupo do misoprostol apresentou menor intensidade da dor durante o procedimento, tanto na comparação das medianas (05 versus 07, p=0,02) quanto nos escores acima de cinco (44,6% versus 66,7%, p=0,01). Não houve diferenças entre os grupos com relação à duração do procedimento (2,4 versus 2,0 min, p=0,3), presença de dor ao exame ou na biópsia (p=0,74 e p=0,19, respectivamente). Não ocorreu diferença na necessidade de dilatação (17,2 versus 20,3, p=0,66) nem na presença de efeitos colaterais ou complicações. Também não se observaram diferenças significativas na presença e intensidade da dor após o procedimento. Conclusão: o uso prévio de misoprostol parece diminuir a intensidade da dor durante a histeroscopia diagnóstica em pós-menopausadas; entretanto não demonstrou diferenças significativas em relação à diminuição do tempo para o procedimento e nem da necessidade de dilatação cervical entre os grupos, sugerindo não utilizá-lo rotineiramente e sim em alguns casos selecionados / Abstract: hysteroscopy is one of the most useful procedure to study uterine cavity and widely used in gynecologic clinic. Although many controlled clinical trials have shown advantages in the use of misoprostol in realeasing cérvix uterine resistanse, there are few evidence regarding its use before office hysteroscopy in postmenopausal women. Objective: to compare the trans and postoperative results of postmenopausal women underwent office hysteroscopy without anesthesia that used misoprostol or placebo previouslly to the procedure to mature the uterine cérvix in two teaching hospitals in Recife. Patients and methods: a randomized, double masked, clinical trial was conducted enrolling 120 postmenopausal women who had been submitted to office hysteroscopy without anesthesia at IMIP and Barão de Lucena teaching hospital. Among those patients 60 were randomized allocated in the study group using 200µg of vaginal misoprostol and 60 took part in the placebo group using 200µg of a vaginal placebo.The following variable were studied: duration of the procedure, frequency and intensity of pain during the exame, necessity of additional dilatation, side effect as (genital bleeding, nauseas, vomits, diarrhea, and hyperthermia) and complications (uterine perforation, false way, cervical laceration, infections and pain in the imediate postoperatory period). For analysis statistics we used the tests of association qui-square, accurate test of Fisher and Mann-Whitney for comparison of the groups, considering itself significant with lesser alpha error that 5%. Results: We found no significant statistic difference between the groups regarding age (61,3 e 59,2, p=0,09), parity (04 e 04, p=0,88), IMC (27 e 27,5, p=0,55) ,time since menopause (12,5 versus 9,6, p=0,52), time between medication and hysteroscopy (8,4 e 8,2, p=0,4), distensor fluid with CO2 (39% versus 32%, p=0,44) and the indication of the exam (myoma, endometrial thickness and postmenopausal bleeding (p=0,52; 0,37; 0,62, respectively).There was no differences between the groups with regard to duration of the procedure, presence of pain to the examination or hystopathologic findings. No differences in the necessity of extra cervical dilatation nor in the presence of side effects or complications was observed. We also didn't find any statistic difference regarding the presence and intensity of pain after the procedure. The misoprostol group had less pain during hysteroscopy than placebo group (p= 0,02). Conclusions: Although the previous use of misoprostol seems to decrease the intensity of pain during the hysteroscopy in postmenopausal women when compared with those who had used placebo, there were no significant difference in duration of procedure and necessity of extra cervical dilataion. Therefore we do not suggest its routinely use, but only in selected cases / Doutorado / Doutor em Tocoginecologia
377

AvaliaÃÃo das AlteraÃÃes HematolÃgicas, BioquÃmicas e GenotÃxicas nos Trabalhadores Expostos à AgrotÃxicos em MunicÃpios do Estado do Piauà / Evaluation of Hematologic, Biochemical and Genotoxic Effects in Workers Exposed to Pesticide in Municipalities of PiauÃ

Vera Regina Cavalcante Barros Rodrigues 26 September 2011 (has links)
nÃo hà / A utilizaÃÃo de agrotÃxicos na agricultura elevou rapidamente seu consumo, especialmente de forma indiscriminada, sendo o Brasil um dos maiores mercados, representando 16% da venda mundial. No PiauÃ, a expansÃo agrÃcola na regiÃo dos cerrados contribuiu para o aumento do seu uso, expondo os agricultores a danos ao DNA. O objetivo desse estudo foi avaliar os efeitos tÃxicos e genotÃxicos nos agricultores piauienses expostos aos agrotÃxicos, com o uso de biomarcadores hematolÃgicos, bioquÃmicos e genotÃxicos. A populaÃÃo estudada consistiu de 60 trabalhadores expostos aos agrotÃxicos dos municÃpios de Barras e Josà de Freitas e 55 indivÃduos controle, sem histÃria de exposiÃÃo a agroquÃmicos. Para caracterizaÃÃo da populaÃÃo foi aplicado questionÃrio sÃcio epidemiolÃgico, de acordo com a International Commission for Protection Against Environmental Mutagens and Carcinogens-ICPEMC. Foram coletados 10 mL de sangue perifÃrico para realizaÃÃo das anÃlises hematolÃgicas, bioquÃmicas e ensaio cometa, que foram processadas pelo LACEN-PI. A mÃdia de idade foi de 34 anos, de etnia negra, na maioria, com tempo de trabalho, em mÃdia de 13,55 anos, carga horÃria de 41,5 horas semanais e 50% dos trabalhadores utilizavam pelo menos um tipo de EPI. Quanto aos hÃbitos de vida, 66,7% dos trabalhadores expostos informou nÃo consumir vegetais, 41,7 % eram fumantes e 73,3% consumiam bebidas alcoÃlicas. Do total do grupo exposto, 33,3% usava medicamentos prescritos e 66,7% usava medicamentos nÃo prescritos. No estudo foi evidenciado maior uso na agricultura de herbicidas (81,1%) e inseticidas (16,3%). No grupo dos trabalhadores expostos, 55% apresentaram leucopenia e 6,7% apresentaram diminuiÃÃo na contagem de cÃlulas vermelhas. Foram evidenciadas alteraÃÃes na creatinina plasmÃtica (p < 0,05); nas transaminases e fosfatase alcalina (p< 0,01) quando comparado o grupo exposto com o nÃo exposto. Nos resultados do ensaio cometa, o grupo exposto apresentou, em relaÃÃo ao grupo nÃo exposto, uma mÃdia de (32,13 vs 10,12) de Ãndice de dano, e frequÃncia do dano (21,82 vs 9,38), respectivamente. Na classe 1, a genotoxicidade observada foi de 17% para os expostos e 9% para os nÃo expostos. NÃo houve significÃncia entre os danos no DNA em relaÃÃo Ãs variÃveis: tempo de trabalho, nÃo uso de EPI, hÃbito de fumar, consumo de Ãlcool e nÃo consumo de vegetais. Conclui-se que os trabalhadores expostos a agrotÃxicos apresentaram alteraÃÃes enzimÃticas, hematolÃgicas (leucopenia) e instabilidade genÃtica, avaliados por parÃmetros bioquÃmicos e genotÃxicos, demonstrando assim a importÃncia do biomonitoramento dos trabalhadores como uma estratÃgia de vigilÃncia em saÃde do trabalhador no Estado do PiauÃ. / The use of pesticides in agriculture rapidly increased their consumption, especially indiscriminate consumption, being Brazil currently the largest market for pesticide in the world, representing 16% of worldwide sales. In the state of PiauÃ, the agricultural expansion in the region of Cerrado contributed to their increased use, exposing farm workers to damages to the DNA. The purpose of this study was to evaluate the toxic and genotoxic effects in farm workers exposed to pesticides in PiauÃ, with the use of hematologic, biochemical and genotoxic biomarkers. The population in analysis consisted of 60 farm workers from the municipalities of Barras and Josà de Freitas occupationally exposed to pesticides and 55 control individuals with no history of exposure to agrochemicals. To obtain the characteristics of the population, a social-epidemiological questionnaire was applied, recommended by International Commission for Protection Against Environmental Mutagens and Carcinogens-ICPEMC. 10 mL of peripheral blood were collected for haematological, biochemical and comet assay analyses, all of which were processed by LACEN-PI. The mean age was 34 years, of black ethnicity, mostly with an average of 13.55 years of work, workload of 41.5 weekly hours and 50% of workers used at least one type of PPE. In what concerns lifestyle, 66.7% of the exposed workers said they did not consume vegetables, 41.7% were smokers and 73.3% consumed alcohol. Of the total of the exposed group, 33.3% used prescribed medication and 66.7% used non-prescribed medication. In the study, it was evidenced a higher use of herbicides (81.1%) and insecticides (16.3%) in agriculture. In the group of exposed workers, 55% had leucopenia and 6.7% showed a decrease in the red blood cell count. It was found variation in plasmatic creatinine (p < 0.05); in liver enzymes and alkaline phosphatise (p < 0.01) when comparing the exposed and the non-exposed groups. In the results of the comet assay, the exposed group showed, in comparison with the non-exposed group, a mean of (32.13 vs. 10.12) of damage index and damage frequency of (21.82 vs. 9.38), respectively. In class 1, the genotoxicity observed was 17% for the exposed and 9% for the non-exposed. There was no significance between DNA damage and the following variables: workload, non-use of PPE, smoking, consumption of alcohol and non-consumption of vegetables. We concluded that workers exposed to pesticides presented toxic variations and genetic instability, which was evidenced by enzymatic variation and damages to the DNA, which thus demonstrates the importance of biomonitoring of workers as a strategy of occupational health surveillance in the state of PiauÃ.
378

Biomonitoramento GenÃtico de Agricultores expostos a Pesticidas nos MunicÃpios de Tianguà e Ubajabra Cearà / Biomonitoring genetic of farmers exposed to pesticides in the municipalities of Tiangua and Ubajara (CearÃ, Brazil).

Jean Carlos Gomes Paiva 16 August 2011 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Nos Ãltimos anos, o uso de pesticidas na agricultura tem aumentado e associaÃÃes entre a exposiÃÃo a produtos quÃmicos agrÃcolas e danos ao DNA e cÃncer tem sido relatados. O Brasil à um dos lÃderes mundiais na utilizaÃÃo de pesticidas, no entanto, estudos que avaliem o impacto da exposiÃÃo ocupacional a pesticidas sobre a incidÃncia e mortalidade por cÃncer ainda sÃo escassos na populaÃÃo brasileira. O teste do cometa alcalino e a anÃlise de aberraÃÃes cromossÃmicas (AC) foram utilizados para avaliar danos primÃrios ao DNA em linfÃcitos do sangue perifÃrico de trabalhadores expostos a uma mistura complexa de pesticidas em duas pequenas comunidades rurais nos municÃpios de Tianguà e Ubajara, localizados no oeste do Estado do Cearà (Nordeste do Brasil). Estes MunicÃpios estÃo entre as maiores Ãreas agrÃcolas do Estado. O teste do cometa mostrou que o Ãndice e freqÃÃncia de danos observados nos grupos expostos foram significativamente maiores em relaÃÃo aos grupos controle (P <0,05). Por outro lado, nÃo foram detectadas diferenÃas significativas em relaÃÃo a AC estruturais e numÃricas nas comunidades avaliadas. AlÃm disso, os nÃveis observados de quebras da fita de DNA e freqÃÃncias de AC, estratificadas por tempo de exposiÃÃo, nÃo foram estatisticamente diferentes nos agricultores de ambas comunidades rurais. Os resultados sugerem que os danos causados por pesticidas na Ãrea de estudo nÃo foram significativos o suficiente para induzir mutaÃÃes permanentes ou interferir na formaÃÃo do aparelho mitÃtico. Danos mÃnimos causados pelos pesticidas podem ter sido submetidos a reparo celular, explicando a ausÃncia de AC estruturais e numÃricas. As anÃlises da Ãgua do reservatÃrio que serve de fonte para irrigaÃÃo das plantaÃÃes e abastece os municÃpios da regiÃo nÃo detectou contaminaÃÃo por resÃduos de pesticidas. / In recent years, the use of pesticides in agriculture has been steadily increasing, and associations between exposure to agricultural chemicals and DNA damage and cancer have been reported. Brazil is one of the world leaders in pesticide use; however, studies that evaluate the impact of pesticide exposure on cancer incidence and mortality are very scarce in the Brazilian population. The alkaline comet assay and the chromosome aberration (CA) test were used to evaluate primary DNA damage in the peripheral blood lymphocytes of workers exposed to a complex mixture of pesticides in two small rural communities in the municipalities of Tianguà and Ubajara, located in the western part of Cearà State (Northeast Brazil), which are among the largest agricultural areas of the state. The comet assay showed that the damage index and damage frequency observed in the exposed groups were significantly higher in relation to the controls (P < 0.05). On the other hand, no differences were detected regarding structural and numerical CAs in the communities evaluated. Additionally, the observed levels of DNA strand breaks and frequencies of CAs, stratified for exposure time, were not statistically different for individuals of either rural community. Our results suggest that the damages caused by pesticides in our study area were not great enough to induce permanent mutations or to interfere with mitotic apparatus formation; minimal pesticide damages could have undergone cellular repair, explaining the absence of structural and numerical CAs. Analyses of water from the reservoir that serves as a source for irrigation of crops and supplies the cities of the region did not detect contamination by pesticides.
379

EXPANDING MONOAMINE TRANSPORTERS PHARMACOLOGY USING CALCIUM CHANNELS

Ruchala, Iwona 01 January 2017 (has links)
Research in drug development meets many challenges including lengthy, complex and costly procedures to identify novel pharmacotherapies. In our lab, we developed a method for fast screening of small molecules that interact with monoamine transports – dopamine and serotonin (DAT, SERT). These membrane proteins play important roles in brain neurotransmission responsible for cognition, motion and pleasure. Dysfunction in dopaminergic and serotonergic systems result in neurological disorders such as depression, Attention Deficit Hyperactivity Disorder (ADHD), schizophrenia and addiction. DAT and SERT are responsible for uptake of dopamine (DA) or serotonin (5HT) into the synapse and they limit neurotransmitter signaling. Drugs that mimic or antagonize actions of endogenous neurotransmitters (DA and 5HT) increase the concentrations of DA and/or 5HT either by blocking the transporter (blockers) or by competing uptake with neurotransmitter (substrate). The uptake of substrates is associated to an inward current that depolarizes the cell membrane. Voltage-gated calcium channels (CaV) can respond to small changes in membrane potential. In our method, we combined permanent cell line expressing the human dopamine transporter (hDAT) or the human serotonin transporter (hSERT) (FlpIn TREx expression system) with transient transfection of CaV. This system works as a tightly electrically coupled system. Cells challenged with substrate of the transports produce detectable Ca2+ signal while monoamine transporter blockers can inhibit these Ca2+ signals. The novelty of this method relies on the ability to discriminate between substrate and blockers of monoamine transporters. Preliminary experiments measuring our optimized cell system in a Flex Station 3 plate reader suggest that the co-expression of a voltage-gated Ca2+ channel, a monoamine transporter and a genetically encoded Ca2+ sensor constitute a rapid screening biosensor to identify active drugs at monoamine transporters. Our novel methodology can rapidly assess drug-effect profile on monoamine transporters and benefit development of new psychotherapeutics for treatment of mental illnesses. It can also be used to characterize mechanism of action of emerging drug of abuse, as well as to discover small molecules with novel drug-effect profile useful in basic neuroscience research.
380

Differentiation between Quinolone Resistant and Sensitive Isolates of Campylobacter jejuni by a Multiplex PCR Assay

Ebrahim, Nazneen January 2006 (has links)
Magister Scientiae - MSc / South Africa

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