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Význam proteinů tepelného šoku v diagnostice a prognostice těhotenských komplikací / Heat shock proteins - - their role in diagnosis and prognosis of pregnancy related complicationsDvořáková, Lenka January 2013 (has links)
Heat shock proteins increase their gene expression after exposure of cells or organisms to some forms of stress, which may be high temperature, infection, inflammation, hypoxia, lack of nutrients and water. Stressful situations for the body are also pregnancy-related complications associated with placental insufficiency - preeclampsia and IUGR, as well as other pregnancy-related complications such as fetal growth restriction and gestational hypertension. Therefore, I examined whether the occurrence of pregnancy-related complications (preeclampsia, fetal growth retardation, gestational hypertension) affect the gene expression of heat shock proteins. Five hsp systems was detected, namely Hsp27, Hsp60, Hsp70, Hsp90 and HspBP1 in placental tissue samples and whole maternal peripheral blood. Samples came from women with physiological pregnancy and from women with certain pregnancy-related complications (PE, FGR, GH). RNA was isolated from the samples. Detection of hsp expression was performed by using real-time RT-PCR and the comparative Ct method. Changes in gene expression between the test samples and reference sample were examined. To assess the difference between physiological pregnancies and pregnancies with selected pregnancy- related complications, an analysis of variance (ANOVA) was used....
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Determinação do perfil de expressão de microRNAs em câncer de mama em mulheres jovens / Identification of microRNAs expression patterns in breast cancer in young womenBastos, Elen Pereira 28 January 2011 (has links)
O câncer de mama em mulheres jovens (idade igual ou abaixo de 35 anos) apresenta-se de forma mais avançada ao diagnóstico, possuindo grau histopatológico menos diferenciado. Além disso, as pacientes apresentam maior taxa de mortalidade e menor sobrevida livre de doença quando comparadas às pacientes menopausadas. Dentre os cânceres de mama em mulheres jovens, apenas 8 a 10% dos casos familiais estão relacionados a mutações nos genes BRCA1 e BRCA2 e esta frequência nos casos esporádicos é ainda menor (3- 10%). Assim, os fatores relacionados à desregulação oncogênica em mulheres jovens com ou sem antecedentes familiares que apresentam testes genéticos negativos para essas mutações não estão suficientemente esclarecidos. Tais evidências sugerem que o câncer em mulheres muito jovens apresenta características biológicas especificas. Considerando que a expressão gênica é regulada em múltiplos níveis, alguns estudos recentes tem referido a importância dos microRNAs neste processo tanto na degradação de RNAs mensageiros como na repressão da tradução. A análise da expressão dos microRNAs em câncer de mama tem revelado perfis característicos de determinados níveis de progressão da doença. No presente trabalho, nosso objetivo foi determinar o perfil de expressão de microRNAs em tumores de mama de mulheres jovens (idade igual ou abaixo de 35 anos) não-portadoras de mutações nos genes BRCA1/2. As pacientes foram subdivididas em 2 grupos [familial (n=8) e não-familial (n=20)] e, em seguida, os dados de expressão foram comparados aos obtidos em amostras normais de mamoplastia. A quantificação da expressão dos microRNAs foi realizada pela reação de RT-PCR em tempo real, utilizando o sistema TaqMan microRNA Assay. As análises estatísticas mostraram 246 miRNAs de expressão diferencial entre os 3 grupos (normal, familial e não-familial) sendo que, destes, encontramos 137 miRNAs diferencialmente expressos entre os grupos familial e normal; 44 miRNAs entre os grupos não-familial e normal e 4 miRNAs entre os grupos familial e não-familial. Nossos dados demonstram que os tumores do grupo de pacientes familiais quando comparados aos normais apresentam um perfil de miRNAs globalmente reduzido. O perfil de expressão de miRNAs no grupo de pacientes com câncer de mama esporádico é pouco distinto do grupo com história familial. Muitos dos miRNAs com expressão reduzida estavam envolvidos, de acordo com a literatura, numa sinalização comum relacionada a mecanismos de proliferação, apoptose e invasão celular. Os 4 miRNAs identificados como diferencialmente expressos entre os grupos familial e nãofamilial embora relacionados com outros tipos de cancer precisam de uma melhor caracterização em cancer de mama / A rise in the incidence of breast cancer among young adult women (with age 35) was observed in recent decades. Breast cancer incidence in young woman has been correlated to poor survival and aggressive features. Due to different type of breast cancers in young woman, 8- 10% with familial history appears with mutation in BRCA1/2 genes, and similar proportion occurs in cases without familial history (3- 10%). However, early onset breast cancer patients with or without familial history, non carriers of BRCA1/BRCA2 mutations is not well elucidated. The deregulation by microRNAs has recently emerged as a major determinant of tumorigenesis. Because miRNAs function by targeting functionally important protein-conding genes, it is of outstanding interest to identify miRNAs involved in the molecular mechanism underlying aggressiveness in tumors of young patients that might represent biomarkers and therapeutic targets. This evidence suggests that breast cancer in young woman has specific biological characteristics. Understanding the patterns of miRNAs expression that potentially alter the regulation of key breast cancer genes we could give a better treatment to these patients. Thirty-two patients were selected: 8 with familial history of breast and ovarian suggestive of hereditary condition according to NCCN criteria and 20 without familial history. Patients of both groups were of non carriers of BRCA1/BRCA2 mutations. The determination of microRNA expression network between those 2 groups was performed by TaqMan microRNA Assay (Applied Biosystems) using as control 3 normal mamoplastia samples from wealthy young women. Data were normalized using endogenous miRNA presented in each array. Statistical comparisons were done using ANOVA and Student T test with adjusted FDR (5%). It was found that 246 miRNAs were differently expressed between the 3 groups. From the comparison of familial group against normal group it was found 137 miRNAs differently expressed. In the comparison between non familial and normal group it was found 44 miRNAs differently expressed. Finally the comparison between familial group and non familial group it was found 4 miRNAs differently expressed. Among these miRNAs are some which was well characterized in breast cancer with down-regulation such as: miR-125b, miR-126 and miR-100. Our findings suggested that tumors from familial or sporadic cases presented discrete differences of microRNA expression patterns. A global downregulation of 137 miRNAs in tumors from familial group of patients when compared to normal group was observed. Based on the literature, most of these miRNAs are related to mechanisms of proliferation, cells migration and apoptosis. To our knowledge, this is the first evidence of miRNA expression in tumors of early onset Breast Cancer patients, non carries BRCA1/2 mutation, providing insights that may lead to the detection of new conducts of treatment
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Caracterização de um novo Potyvirus causador de mosaico foliar e variegação floral em Catharanthus roseus / Partial characterization of a Potyvirus causing mosaic and flower variegation in Catharanthus roseusMaciel, Scheila da Conceição 03 August 2007 (has links)
A vinca (Catharanthus roseus) é uma planta perene, arbustiva, pertencente à família Apocinaceae, cujas folhas e raízes possuem propriedades medicinais. A presença de sintoma de mosaico e deformação foliar em plantas dessa espécie, associados com a presença de partículas alongadas e flexuosas, característica de vírus pertencentes ao gênero Potyvirus, conduziu a estudos complementares para a identificação e caracterização desse vírus. No estudo da gama parcial de hospedeiras foram testadas 28 espécies, envolvendo oito famílias botânicas. Catharanthus roseus e Nicotiana benthamiana apresentaram sintomas de mosaico foliar e Chenopodium amaranticolor e C. quinoa apresentaram lesões locais cloróticas nas folhas inoculadas. A transmissão do vírus com afídeos foi avaliada com as espécies Aphis gossypii, Myzus nicotianae e Toxoptera citricidus. Apenas Aphis gossypii e Myzus nicotianae transmitiram o vírus. O antissoro policlonal produzido contra este potyvirus reagiu com o vírus homólogo e com o Passionfruit woodiness virus (PWV) e Cowpea aphid-borne mosaic virus (CABMV), mas não com o Lettuce mosaic virus (LMV), Papaya ringspot virus - type W (PRSV-W), Potato virus Y (PVY) e Zucchini yellow mosaic virus (ZYMV). O peso molecular da proteína capsidial (CP) foi de aproximadamente 34 kDa. A reação de PCR realizada com os oligonucleotídeos universais de potyvirus e oligonucleotídeos específicos posteriomente confeccionados amplificaram três fragmentos de aproximadamente 0,8, 1,0 e 1,4 Kb, os quais após o seqüênciamento geraram um fragmento de 1654 nucleotídeos (nt) da região 3' terminal do genoma, que inclui parte do gene da replicase viral (Nib), a região codificadora completa do gene da proteína capsidial (CP), seguida de 286 nt da região 3' não traduzida (3'NTR). A identidade da seqüência de nucleotídeos do gene da CP variou de 67,0 a 76,0%, quando comparada com as de outros membros da família Potyviridae. A maior identidade foi com o Omphalodes virus Y (76,0%). A identidade dos aminoácidos deduzidos da proteína capsidial variou de 62,0 a 71,0%, sendo a maior com East Asian Passiflora virus (71%). Para a região não traduzida (3'NTR) a identidade variou de 16,8 a 28,6%. Em conjunto esses dados indicam que este vírus é uma nova espécie dentro do gênero Potyvirus, para o qual se propõe o nome de Vírus do mosaico do Catharanthus (Catharanthus mosaic virus - CatMV). / Catharanthus roseus is known as the common periwinkle or Madagascar periwinkle. It is a perennial, evergreen herb in the family Apocynaceae, which was originally native to the island of Madagascar, although both name and classification are contradictory in some literature. The plants grow up to 80 cm high; have glossy, dark green leaves and bloom during summer. The flowers range from white to hot pink to purple. The species has historically been used in popular medicine to treat a wide assortment of human diseases, as it contains more than 150 useful alkaloids. Plants of C. roseus exhibiting mosaic symptoms followed by malformation of the leaf blades and flower variegation were collected from a garden at the University of São Paulo, School of Agriculture (Piracicaba, State of São Paulo, Brazil). Preliminary electron microscopy exams of negatively stained leaf sap revealed that the symptoms were associated with potyvirus-like particles. The objective of the present work was to obtain further biological, immunological and molecular data to better characterize this species of the genus Potyvirus, family Potyviridae. Of 28 plant species from eight botanical families inoculated mechanically with this potyvirus, only C. roseus and Nicotiana benthamiana developed systemic mosaic, whereas Chenopodium amaranticolor and C. quinoa exhibited only chlorotic local lesions. The virus was transmitted by Aphis gossypii and Myzus nicotianae, but not by Toxoptera citricidus. Polyclonal antiserum raised against this potyvirus reacted with the homologous virus, Passion fruit woodiness virus (PWV) and Cowpea aphid borne mosaic virus (CABMV) in PTA-ELISA. The molecular mass of the coat protein (CP) was approximately 34 kDa. RT-PCR from viral RNA amplified a fragment of approximately 1654 nucleotides (nt) at the 3'-terminal of the viral genome, containing portion of the replicase gene (Nib), the entire CP gene and the 3' untranslated region (3'UTR) (286 nt). When the nucleotide sequence of the CP gene was compared with other members of the Potyviridae family, identities varied from 67.0 to 76.0%. The highest identity was with Omphalodes virus Y. Identity of the deduced amino acid of the CP varied from 62.0 to 71.0%, with the highest for East Asian Passiflora virus. For the 3' UTR, identities varied from 16.8 to 28.6%. The name Catharanthus mosaic virus (CatMV) is proposed for this new potyvirus.
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In Vitro Analysis of FGF-23 Induced Gene ExpressionPazmany, Csaba C. 14 January 2003 (has links)
Fibroblast growth factor 23 (FGF-23) has recently been shown to be involved in phosphate regulation and bone mineralization. This study evaluated the effect of FGF-23 on three human cell lines (Caco-2, HK-2, SaOS-2) representing three different sites of phosphate regulation (small intestine, kidney proximal tubules, and bone, respectively). FGF-23 induced gene expression was studied using Clontech human Atlas glass microarrays containing various assortments of genes and by a custom designed oligo microarray containing specific genes selected for their biological relevance to FGF-23's potential function. FGF-23 induced differential gene expression in all three cell types, suggesting that FGF-23 may be capable of acting on these three primary sites of phosphate regulation. Human small intestine-like endothelial cell line, Caco-2, showed upregulation of several genes including parathyroid hormone receptors 1 and 2. FGF-23 inhibited the expression of water channel transporters aquaporin 5 and 6 in human osteoblast-like SaOS-2 cells while upregulating aquaporin expression in HK-2 cells. Somatostatin receptors 1-4 were identified to be upregulated in the human kidney, HK-2 cell line. Mucin 2, a gene that is linked to abnormal cellular growth, was consistently induced by FGF-23 in all three cell lines. Families of aquaporins, somatostatins, parathyroid hormones, and other identified differentially expressed genes are involved in different signaling pathways that are associated with phosphate and calcium regulation. Selected candidates were analyzed further by real-time RT-PCR. These data support FGF-23 induced regulation of aquaporin 5 mRNA in HK-2 cells and 1-alpha-hydroxylase mRNA in Caco cells. FGF-23 induced changes in mRNA analysis of four additional genes was less than two-fold in triplicate analysis of selected samples. Taken together, these results suggest that each cell type may have responded to FGF-23, but additional validation of the array data set will be required to identify those genes specifically regulated by FGF-23. Further refinement of this data set will undoubtedly uncover additional functions of FGF-23 and may provide valuable insight into designing therapeutic approaches for phosphate specific disorders.
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Alterations moleculaires au cours de la carcinogenese urotheliale vesicale / Molecular alterations during bladder urothelial carcinogenesisPignot, Géraldine 14 December 2011 (has links)
Le cancer de vessie représente la sixième cause de mortalité par cancer en France. Son incidence a augmenté ces 20 dernières années, mais les taux de survie restent inchangés. La carcinogénèse vésicale fait intervenir différents mécanismes moléculaires qui agissent en réseau comme c’est le cas dans de nombreux cancers. Le développement récent de nouveaux traitements prenant spécifiquement pour cible certaines voies de signalisation apportent de nouveaux espoirs thérapeutiques. Nous nous sommes intéressés dans ce travail à trois axes de recherche pour tenter d’identifier, dans les carcinomes urothéliaux, de nouveaux marqueurs pronostiques moléculaires et de nouvelles cibles thérapeutiques potentielles: l’angiogénèse, la voie de signalisation Hedgehog et les microARNs. Nous avons choisi la RT-PCR quantitative en temps réel à grande échelle permettant d’évaluer le niveau d’expression de nombreux gènes, avec une quantification précise et reproductible des transcrits. L’expression de ces gènes a été corrélée aux données de suivi clinique afin d’identifier de nouveaux biomarqueurs moléculaires prédictifs de l’évolution des tumeurs de vessie.Nous avons ainsi pu démontrer que les niveaux d’expression de certains de ces gènes variaient de façon significative dans les tumeurs de vessie, confirmant le rôle de l’angiogénèse dans la carcinogénèse urothéliale, et plus particulièrement de la voie du VEGF, et suggérant une implication majeure de la voie de signalisation Hedgehog et des microARNs. Par ailleurs, nous avons également pu identifier plusieurs biomarqueurs ayant une valeur pronostique en terme de survie globale dans les tumeurs infiltrantes. C’est le cas du VEGF, qui semble être un biomarqueur moléculaire particulièrement intéressant puisqu’il existe des thérapies ciblées spécifiquement dirigées contre ce ligand ou ses récepteurs avec plusieurs essais cliniques actuellement en cours dans le cancer de vessie. C’est également le cas d’une signature moléculaire associant 3 miARNs (miR-9, miR-182 et miR-200b) ayant une valeur péjorative dans les tumeurs infiltrantes, ouvrant la voie vers de nouvelles stratégies thérapeutiques.L’ensemble de ces études confirment l’intérêt majeur d’une meilleure compréhension des bases moléculaires de la carcinogénèse urothéliale vésicale débouchant sur l’utilisation rationnelle de nouvelles thérapies ciblées dans le cancer de vessie, avec l’espoir d’en améliorer la prise en charge et l’évolution. / Bladder cancer is the sixth cause of cancer mortality in France and its incidence is increasing since the last 20 years, with no improvement in survival outcomes. Bladder carcinogenesis involves different molecular mechanisms such as in many cancers. The recent development of new targeted therapies targeting signaling pathways provides new therapeutic hopes.In this work, we choose to study three molecular pathways in order to identify new prognostic markers and new therapeutic targets in urothelial carcinoma: angiogenesis, Hedgehog signaling pathway, and microRNAs. Real-time quantitative RT-PCR was performed to measure simultaneously expression levels of several genes with precise and reproductible RNA quantification. Our results were correlated with clinical outcomes to identify new molecular markers associated with bladder cancer evolution and to guide the potential use of targeted therapies.We were able to demonstrate that expression levels of several transcripts differ significantly in bladder tumors as compared to normal bladder and that some of them may have a prognostic implication. This is the case of VEGF, which appears to be an interesting molecular marker since there are targeted therapies specifically targeting the pathway and several ongoing trials in bladder cancer. The Hedgehog pathway also appears to be altered in bladder tumors, with a ligand-dependent activation. Then, we were able to identify several deregulated microRNAs and describe a molecular 3 miRNA-signature (miR-9, miR-182 and miR-200b) having a prognostic value in muscle-invasive bladder tumors. All these studies confirm the major interest of molecular biology and new targeted therapies in the treatment of bladder cancer, with the hope of improving management and evolution.
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Cinomose Canina : detecção do RNA viral pela reação em cadeia pela polimerase (RT-PCR) em cães com diagnóstico clínico da doença. / Canine distemper vírus : detection of viral RNA by RT-PCR in dogs with clinical diagnosis.Alcalde, Rosana 08 December 1999 (has links)
O vírus da cinomose canina (VCC) é um patógeno viral, altamente, contagioso que pode causar doença sistémica letal, em cães e outros carnívoros em toda parte do mundo. Os cães afetados podem apresentar sintomas gastrentéricos, respitatórios e nervosos. As manifestações clínicas da doença inclue depressão, diarréia, vómito, desidratação, hiperqueratose dos coxins e focinho e espasmos musculares ou paresia de membros pélvicos, a qual pode persistir por longos períodos. Cães infectados, com sintomas clínicos de VCC, foram estudados para detecção do RNA viral pela técnica de PCR e Nested-PCR. Neste estudo, amplificou-se o gene da nucleoproteína (NP) em células mononucleares do sangue periférico (linfócitos), urina e saliva, de cães infectados com VCC, para detectar o genoma do mesmo, por RT-PCR, em diferentes amostras clínicas. A identificação do RNA viral foi concluída com sucesso, pelo método de RT-PCR, utilizando 2 pares de \"primers\" específicos do gene da nucleoproteína (NP). A técnica de RT-PCR, descrita neste etudo, pode ser um sistema de ensaio útil para determinar se cães suspeitos de infecção, por VCC, tenha níveis detectáveis de genes. Os resultados demonstram que a técnica de RT-PCR é exequível para o diagnóstico laboratorial de cinomose canina. / Canine distemper vírus (CDV) is a highly contagious Viral pathogen which may cause lethal systemic in dogs and other carnivores throughout the world. Affected dogs show gastrointestinal and respiratory clinical slgns, and frequently develop clinical signs in the central nervous system (CNS). Clinical manifestations of the disease include depression, progressive loss of weight, dehydration, hyperkeratosis of the foot pads and nose, nervous symptoms and muscular spasms or posterior paralysis which may perslst for long periods. Infected dogs with clinical symptoms for CDV, were by detection of viral RNA by Polymerase Chaln Reaction (PCR) and Nested PCR. In this study,w e determinebdy the RT-PCRth e presenceo f nucleoprotein (NP) gene in peripheral blood mononuclear cells, urine and saliva from dogs infected with CDV. The goals of this study was to detect CDV renome by RT-PCR in different clinical samples. In this study, Identificatlon of NP mRNA was successfully achieved by using the RT-PCR method with two sets of NP gene specific primers. The RT-PCR technique described in thls study, may provide a useful assay system to determine whether the dogs suspected of CDV infection have detectable leveis of CDV genes. The results demonstrate that RT-PCR technique is rapid, sensitivity and specificity for vírus diagnosis.
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ExpressÃo gÃnica da toxina da soja (SBTX) durante o desenvolvimento da soja [Glycine max (L.) Merril] e seu envolvimento na defesa vegetal / Gene expression of soybean toxin ( SBTX ) during the development of soybean [ Glycine max ( L.) Merrill ] and their involvement in plant defenseMariana Reis Arantes 05 March 2015 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O Brasil à o segundo maior produtor mundial de soja, destacando-se por sua multiplicidade de uso. Entretanto, perdas na produtividade de seus grÃos em campo sÃo ainda considerÃveis, particularmente oriundas das doenÃas causadas por fungos. Diante desse obstÃculo, emerge a necessidade de busca de molÃculas naturais capazes de inibir o progresso dessas doenÃas, sem causar impactos ambientais. Dentre as molÃculas presentes na soja, com potencial de uso para essa finalidade, destaca-se a toxina da soja (SBTX), uma proteÃna isolada de sementes, composta por duas subunidades (17 e 27 kDa) e ativa contra fungos fitopatogÃnicos. Esse trabalho teve como objetivos verificar a localizaÃÃo tecidual da SBTX em cotilÃdones de sementes maduras, bem como avaliar seu perfil de expressÃo gÃnica ao longo do desenvolvimento da soja e, tambÃm, em resposta ao tratamento com elicitores de defesa vegetal. Sementes de soja foram cultivadas em casa de vegetaÃÃo e, ao longo do desenvolvimento da planta, diferentes tecidos vegetais coletados. Em adiÃÃo, folhas primÃrias da soja foram tratadas com Ãcido salicÃlico (AS) ou inoculadas com esporos do fungo Cercospora kikuchii (CK) e coletadas em diferentes tempos apÃs os tratamentos. Iniciadores foram desenhados com base nas sequÃncias NH2-terminal das subunidades de SBTX e a expressÃo gÃnica foi avaliada pela tÃcnica de RT-PCR quantitativa. A localizaÃÃo de SBTX em sementes foi avaliada por imunohistoquÃmica, usando anti-SBTX. Transcritos dos genes SBTX17 e SBTX27 foram detectados em todos os tecidos vegetais coletados, porÃm seus nÃveis de expressÃo foram diferenciados. NÃveis mais elevados de transcritos para ambas as subunidades da SBTX foram detectados em sementes maduras, cotilÃdones e folhas unifoliadas. Nos cotilÃdones, SBTX foi encontrada na epiderme. InduÃÃo da expressÃo de transcritos da SBTX ocorreu em ambos os tratamentos, porÃm essa resposta se manifestou mais rÃpida (a partir de 6 h) com CK ao invÃs de AS (a partir de 12 h). Praticamente, em todas as anÃlises, transcritos do gene SBTX27 prevaleceram em relaÃÃo Ãqueles do SBTX17. A presenÃa constitutiva e ubÃqua de transcritos dos genes da SBTX ao longo do desenvolvimento da planta, a induÃÃo da expressÃo desses genes por elicitores de resposta de defesa e a localizaÃÃo da toxina na superfÃcie dos cotilÃdones validam o papel de defesa atribuÃdo a SBTX, suscitando a possibilidade de uso dessa proteÃna na produÃÃo de soja resistente ao ataque de fungos de relevÃncia agronÃmica. / Brazil is the second major global soybean producer, whose magnitude is due to its use multiples. However, losses in productivity of soybean grains in the field are still significant, especially those caused by pathogenic fungi. In view of this obstacle, it is important to search natural molecules able to inhibiting the progress of fungal diseases in an environmental friendly practice. Among the soybean molecules which could be used for this purpose, the soybean toxin (SBTX) stands out. SBTX is a protein composed of two subunits (17 and 27 kDa) isolated from seeds with in vitro activity against phytopathogenic fungi. The present study aimed to verify the SBTX tissue localization in soybean seed cotyledons, as well as to evaluate the gene expression profile of two SBTX subunits, both in different stages of plant development and in response to treatment with plant defense elicitors. Soybean seeds were grown in a greenhouse and plant tissues harvested at different days. In addition, soybean primary leaves were treated with salicylic acid (SA) or inoculated with the Cercospora kikuchiii (CK) spores and harvested at different times after the treatments. Based on the N-terminal sequences of the SBTX subunits, primers were designed and their gene expression evaluated by quantitative real-time PCR technique. SBTX tissue localization was performed by immunohistochemistry using anti-SBTX. Transcripts for both SBTX subunits were detected in all plant tissues, predominantly in cotyledons and unifoliate leaves in the early stages of their development, as well as in mature seeds. SBTX was found in the epidermis of the cotyledons. Transcripts were detected for both genes SBTX17 e SBTX27 in all tissues collected, but their expression levels were different. The highest transcript levels for both SBTX subunits were found in mature seeds, cotyledons and unifoliate leaves. In cotyledons, SBTX was found in the epidermis. Leaves treated with elicitors showed induction of the corresponding 17 and 27 kDa subunit transcripts, however this response was earlier in the CK treatment (from 6 h) compared to AS treatment (from 12 h). In almost all analyses, the highest transcript levels were found for the 27 kDa subunit. The ubiquitous and constitutive gene expression during plant development, the induction of gene expression by defense response elicitors and the localization on the surface of cotyledons support the role of SBTX in plant defense and its use to produce fungal-resistant transgenic soybean plants.
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Cinomose Canina : detecção do RNA viral pela reação em cadeia pela polimerase (RT-PCR) em cães com diagnóstico clínico da doença. / Canine distemper vírus : detection of viral RNA by RT-PCR in dogs with clinical diagnosis.Rosana Alcalde 08 December 1999 (has links)
O vírus da cinomose canina (VCC) é um patógeno viral, altamente, contagioso que pode causar doença sistémica letal, em cães e outros carnívoros em toda parte do mundo. Os cães afetados podem apresentar sintomas gastrentéricos, respitatórios e nervosos. As manifestações clínicas da doença inclue depressão, diarréia, vómito, desidratação, hiperqueratose dos coxins e focinho e espasmos musculares ou paresia de membros pélvicos, a qual pode persistir por longos períodos. Cães infectados, com sintomas clínicos de VCC, foram estudados para detecção do RNA viral pela técnica de PCR e Nested-PCR. Neste estudo, amplificou-se o gene da nucleoproteína (NP) em células mononucleares do sangue periférico (linfócitos), urina e saliva, de cães infectados com VCC, para detectar o genoma do mesmo, por RT-PCR, em diferentes amostras clínicas. A identificação do RNA viral foi concluída com sucesso, pelo método de RT-PCR, utilizando 2 pares de \"primers\" específicos do gene da nucleoproteína (NP). A técnica de RT-PCR, descrita neste etudo, pode ser um sistema de ensaio útil para determinar se cães suspeitos de infecção, por VCC, tenha níveis detectáveis de genes. Os resultados demonstram que a técnica de RT-PCR é exequível para o diagnóstico laboratorial de cinomose canina. / Canine distemper vírus (CDV) is a highly contagious Viral pathogen which may cause lethal systemic in dogs and other carnivores throughout the world. Affected dogs show gastrointestinal and respiratory clinical slgns, and frequently develop clinical signs in the central nervous system (CNS). Clinical manifestations of the disease include depression, progressive loss of weight, dehydration, hyperkeratosis of the foot pads and nose, nervous symptoms and muscular spasms or posterior paralysis which may perslst for long periods. Infected dogs with clinical symptoms for CDV, were by detection of viral RNA by Polymerase Chaln Reaction (PCR) and Nested PCR. In this study,w e determinebdy the RT-PCRth e presenceo f nucleoprotein (NP) gene in peripheral blood mononuclear cells, urine and saliva from dogs infected with CDV. The goals of this study was to detect CDV renome by RT-PCR in different clinical samples. In this study, Identificatlon of NP mRNA was successfully achieved by using the RT-PCR method with two sets of NP gene specific primers. The RT-PCR technique described in thls study, may provide a useful assay system to determine whether the dogs suspected of CDV infection have detectable leveis of CDV genes. The results demonstrate that RT-PCR technique is rapid, sensitivity and specificity for vírus diagnosis.
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Islet Xenotransplantation : An Experimental Study of Barriers to Clinical Transplantation / Xenotransplantation av Langerhanska öar : Experimentiella studier av hinder för klinisk tillämpningSchmidt, Peter January 2004 (has links)
<p>In the field of transplantation, the increasing deficit of human donors have lead to an interest in animals as an alternative source of organs and tissues. </p><p>Different <i>in vitro </i>systems and rodent models of xenotransplantation were used to examine the most significant barriers that have to be overcome, before isolated islets of Langerhans from pigs can be used as a cure for insulin-dependent diabetes mellitus in humans.</p><p>In clinical transplantation, islets are infused into the liver through the portal vein. During this procedure the islets are susceptible to harmful innate reactions triggered in blood. Adenoviral vectors generating transgenic expression of human complement regulatory proteins were evaluated in pig islets and shown to confer protection against acute complement-mediated damage. </p><p>Transplanted islets escaping this immediate destruction will be targets of a cellular immune response. Using a new mouse model of islet xenograft rejection, it was demonstrated that macrophages, effector cells in the rejection, were part of an MHC-restricted xenospecific immune response mediated by T cells. In a strain of knockout mice it was further shown that this process can proceed in the absence of an important signalling system, mediated by Toll-like receptors, between cells in innate and adaptive immunity. These findings illustrate some of the mechanistic differences compared to cellular islet allograft rejection which partly explain why immunosuppressive drugs used in clinical allotransplantation is not sufficient for preventing xenograft rejection. </p><p>Porcine endogenous retroviruses (PERV) remain a safety concern in xenotransplantation. Characterization of PERV in pig islets indicated that virus expression is low <i>in vitro </i>but increases during the immediate time period following transplantation. This suggests that antiviral therapies administered at the time of transplantation could be used for preventing the risk of PERV transmission after xenotransplantation.</p>
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Qualitative and Quantitative Assessment of Cytochromes P450 mRNA in Human : Studies in the Liver, Blood and Gastrointestinal MucosaThörn, Mari January 2005 (has links)
<p>Drugs and other foreign compounds must often be metabolised before they can be excreted from the body. One enzyme system that is responsible for this is the cytochrome P450 gene family (CYP). In this thesis, new sensitive molecular techniques have been used to study the human gene expression of some CYP enzymes, as well as the P-glycoprotein transporter (P-gp). The aim was to evaluate whether tissues other than the liver, e.g. the blood, could be used to assess an individual's drug metabolic capacity. Another aim was to investigate the gene expression in relation to the liver transplant process and a third aim was to evaluate the expression in gastrointestinal mucosa in both normal and inflamed mucosa.</p><p>We evaluated the CYP gene expression in paired specimens of liver and blood but found no correlation in the expression patterns of these two tissues. Instead, we found the opposite pattern, where, for example, CYP1B1 had the highest expression in the blood but the lowest in the liver and CYP2E1 was the enzyme with the highest expression in the liver. In an investigation of the expression of four different CYP enzymes and P-gp in liver transplants before and during the first year after transplantation, we found that the levels of all the CYP enzymes but not P-gp increased with time. We also found that the expression of CYP3A4 was inversely related to the normalised plasma levels of the immunosuppressive drugs cyclosporine and tacrolimus.</p><p>In the gastrointestinal tract, CYP2E1 was the enzyme with the highest mRNA expression compared with CYP3A4, CYP3A5 and the transporter P-gp. CYP3A4 has its highest expression in the duodenum compared with the expression in the stomach and the colon. CYP3A5 is expressed at a higher level than CYP3A4 in the colon. P-gp expression levels increase through the gastrointestinal tract to the left colon. Gene expression levels of CYP2E1 and CYP3A4 decrease in severely inflamed rectal mucosa. </p><p>In conclusion, this is a sensitive method for studying gene activity in a clinical situation, even though at this point we are not able to use blood or gastrointestinal mucosa as “surrogate” tissue to estimate an individual’s drug metabolic capacity. The studies in liver transplants and gastrointestinal mucosa are unique in that the gene expression is investigated during a clinical course of events.</p>
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