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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.
61

In vitro studies on the mechanisms of hyperthermia- and TNF-α-induced apoptosis.

January 2002 (has links)
by Yuen Wai Fan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 211-232). / Abstracts in English and Chinese. / Acknowledgements --- p.i / List of Publications and Abstracts --- p.ii / Abbreviations --- p.iv / Abstract --- p.xi / Abstract in Chinese --- p.xiv / List of Figures --- p.xvii / List of Tables --- p.xxiii / Contents --- p.xxiv / Chapter Chapter 1. --- General Introduction --- p.1 / Chapter 1.1 --- Hyperthermia --- p.2 / Chapter 1.1.1 --- History of Hyperthermia --- p.2 / Chapter 1.1.2 --- Biological Functions of Hyperthermia --- p.3 / Chapter 1.1.3 --- Clinical Application of Hyperthermia --- p.4 / Chapter 1.1.3.1 --- Whole-body Hyperthermia --- p.4 / Chapter 1.1.3.2 --- Regional Hyperthermia --- p.4 / Chapter 1.1.3.3 --- Local Hyperthermia --- p.5 / Chapter 1.1.4 --- Combination Therapy --- p.5 / Chapter 1.1.4.1 --- Combined treatment with Hyperthermia and Radiotherapy --- p.6 / Chapter 1.1.4.2 --- Combined treatment with Hyperthermia and Chemotherapy --- p.6 / Chapter 1.2 --- Tumour Necrosis Factor --- p.9 / Chapter 1.2.1 --- History of Tumour Necrosis Factor --- p.9 / Chapter 1.2.2 --- Sources of TNF-α and TNF-β --- p.9 / Chapter 1.2.3 --- Biological Roles of TNF --- p.10 / Chapter 1.2.3.1 --- Receptors of TNF-α --- p.11 / Chapter 1.2.4 --- Signaling Pathway of TNF --- p.12 / Chapter 1.2.4.1 --- Activation of Death Domain --- p.12 / Chapter 1.2.4.2 --- Activation of Sphingomyelin Pathway --- p.13 / Chapter 1.2.4.3 --- Activation of NF-kB pathway --- p.13 / Chapter 1.3 --- Types of Cell Death: Necrosis and Apoptosis --- p.16 / Chapter 1.3.1 --- Necrosis --- p.16 / Chapter 1.3.2 --- Apoptosis --- p.16 / Chapter 1.4 --- Signaling Pathway in Apoptosis --- p.19 / Chapter 1.4.1 --- Factors Involved in Apoptotic Pathway --- p.19 / Chapter 1.4.1.1 --- Caspases --- p.19 / Chapter 1.4.1.2 --- Death Substrates --- p.20 / Chapter 1.4.1.3 --- Bcl-2 Protein Family --- p.21 / Chapter 1.4.1.4 --- Role of Mitochondria --- p.23 / Chapter 1.5 --- Objectives of the Project --- p.26 / Chapter Chapter 2. --- Materials and Methods --- p.28 / Chapter 2.1 --- Materials --- p.29 / Chapter 2.1.1 --- Culture of Cells --- p.34 / Chapter 2.1.1.1 --- "TNF-α Sensitive Cell Line, L929" --- p.34 / Chapter 2.1.1.2 --- "TNF-α Resistance Cell Line, L929-11E" --- p.34 / Chapter 2.1.1.3 --- Preservation of Cells --- p.35 / Chapter 2.1.2 --- Culture Media --- p.36 / Chapter 2.1.2.1 --- RPMI 1640 (Phenol Red Medium) --- p.36 / Chapter 2.1.2.2 --- RPMI 1640 (Phenol Red-Free Medium) --- p.36 / Chapter 2.1.3 --- Buffers and Reagents --- p.37 / Chapter 2.1.3.1 --- Preparation of Buffers --- p.37 / Chapter 2.1.3.2 --- Buffer for Common Use --- p.37 / Chapter 2.1.3.3 --- Reagents for Annexin-V-FITC/PI assay --- p.37 / Chapter 2.1.3.4 --- Reagents for Cytotoxicity Assay --- p.37 / Chapter 2.1.3.5 --- Reagents for Molecular Biology Work --- p.38 / Chapter 2.1.3.6 --- Reagents for Western Blotting Analysis --- p.38 / Chapter 2.1.4 --- Chemicals --- p.40 / Chapter 2.1.4.1 --- Recombinant Murine TNF-α --- p.40 / Chapter 2.1.4.2 --- Dye for Cytotoxicity Assay --- p.41 / Chapter 2.1.4.3 --- Fluorescence Dyes --- p.41 / Chapter 2.1.4.4 --- Chemicals Related to Mitochondrial Studies --- p.41 / Chapter 2.1.4.5 --- Inhibitors of Caspases --- p.42 / Chapter 2.1.4.6 --- Antibodies for Western Blotting --- p.42 / Chapter 2.1.4.7 --- Other Chemicals --- p.43 / Chapter 2.2 --- Methods --- p.44 / Chapter 2.2.1 --- Treatment with TNF-α --- p.44 / Chapter 2.2.2 --- Treatment with Hyperthermia --- p.44 / Chapter 2.2.3 --- In vitro Cell Cytotoxicity Assay --- p.45 / Chapter 2.2.4 --- Flow Cytometry --- p.46 / Chapter 2.2.4.1 --- Introduction --- p.46 / Chapter 2.2.4.2 --- Analysis by FCM --- p.48 / Chapter 2.2.4.3 --- Determination of Apoptotic and Late Apoptotic/Necrotic Cells with Annexin-V-FITC/PI Cytometric Analysis --- p.50 / Chapter 2.2.4.4 --- Determination of Mitochondrial Membrane Potential (ΔΨm) --- p.51 / Chapter 2.2.4.5 --- Determination of Hydrogen Peroxide (H202) Release --- p.52 / Chapter 2.2.4.6 --- Determination of Intracellular Free Calcium ([Ca2+]i) Level --- p.52 / Chapter 2.2.4.7 --- Determination of the Relationship of ΔΨm and [Ca2+]i Level --- p.53 / Chapter 2.2.5 --- Western Blotting Analysis --- p.53 / Chapter 2.2.5.1 --- Preparation of Proteins from Cells --- p.53 / Chapter 2.2.5.2 --- SDS Polyacrylamide Gel Electophoresis (SDS- PAGE) --- p.56 / Chapter 2.2.5.3 --- Electroblotting of Proteins --- p.57 / Chapter 2.2.5.4 --- Probing Antibodies for Proteins --- p.57 / Chapter 2.2.5.5 --- Enhanced Chemiluminescence (ECL) assay --- p.58 / Chapter 2.2.6 --- Reverse Transcriptase Polymerase Chain Reaction --- p.58 / Chapter 2.2.6.1 --- Extraction of RNA by Trizol Reagent --- p.59 / Chapter 2.2.6.2 --- Determination of the Amount of RNA --- p.60 / Chapter 2.2.6.3 --- Agarose Gel Electrophoresis --- p.60 / Chapter 2.2.6.4 --- Reverse Transcription --- p.63 / Chapter 2.2.6.5 --- Polymerase Chain Reaction (PCR) --- p.63 / Chapter 2.2.6.6 --- Design of Primers for Different Genes --- p.64 / Chapter 2.2.6.7 --- Determination of the Number of Cycles in PCR for Different Genes --- p.67 / Chapter 2.2.7 --- Caspase Fluorescent Assay --- p.67 / Chapter 2.2.7.1 --- Caspase-3 or ´ؤ8 Assay --- p.67 / Chapter Chapter 3. --- Results --- p.59 / Chapter 3.1 --- Studies of the Characteristics of L929 and L929-11E cells --- p.70 / Chapter 3.1.1 --- Determination of the Growth Curve of L929 and L929-11E Cells --- p.70 / Chapter 3.2 --- Studies on the Effect of TNF-α on L929 and L929-11E Cells --- p.73 / Chapter 3.2.1 --- TNF-α Induced Cell Death in L929 Cells but not in L929- 11E Cells --- p.73 / Chapter 3.2.2 --- TNF-α Induced Apoptosis in a Time-dependent Manner in L929Cells but not in L929-11E Cells --- p.80 / Chapter 3.2.3 --- TNF-α Induced Mitochondrial Membrane Depolarization in a Time-dependent Manner in L929 Cells but notin L929-11E Cells --- p.87 / Chapter 3.2.4 --- TNF-α Induced Cytochrome c Release in a Time- dependent Manner in L929 Cells but not in L929-11E Cells --- p.92 / Chapter 3.3 --- Effect of Hyperthermia on L929 and L929-11E Cells --- p.96 / Chapter 3.3.1 --- Introduction --- p.95 / Chapter 3.3.2 --- Hyperthermia Induced Apoptosis in L929 and L929-11E Cells --- p.96 / Chapter 3.3.3 --- Effect of Hyperthermia on Mitochondrial Membrane Depolarization --- p.100 / Chapter 3.3.4 --- Hyperthermia Induced Cyto c Release in a Time-dependent Manner in L929 and L929-11E Cells --- p.105 / Chapter 3.4 --- Relationship of Hyperthermia and TNF-α with PTP in L929 Cells --- p.107 / Chapter 3.5 --- Effect of TNF-α and Hyperthermia on the Level of Hydrogen Peroxide (H202) in L929 and L929-11E Cells --- p.114 / Chapter 3.5.1 --- Introduction --- p.114 / Chapter 3.5.2 --- TNF-α Enhanced the Level of H202 in L929 cells but not in L929-11E Cells --- p.115 / Chapter 3.5.3 --- Hyperthermia Enhanced the Level of H202 in L929 and L929-11E cells --- p.117 / Chapter 3.6 --- Effect of TNF-α and Hyperthermia on the Level of Intracellular Calcium in L929 and L929-11E Cells --- p.122 / Chapter 3.6.1 --- Increase in the Intracellular Calcium Level Induced by TNF-α Was Related to the Mitochondrial Membrane Depolarization in L929 Cells but not in L929-11E Cells --- p.122 / Chapter 3.6.2 --- Hyperthermia Increased the Level of [Ca2+]i in L929 and L929-11E Cells in a Time-dependent Manner --- p.124 / Chapter 3.7 --- Effect of Combined Hyperthermia and TNF-α Treatment on the Induction of Apoptosis in L929 and L929-1 1E Cells --- p.129 / Chapter 3.7.1 --- Combined Treatment with Hyperthermia and TNF- α Induced Apoptosis in Both L929 and L929-11E cells --- p.129 / Chapter 3.7.2 --- Hyperthermia and Its Combined Treatment with TNF-α Induced Mitochondrial Membrane Depolarization in L929 and L929-11E Cells --- p.135 / Chapter 3.8 --- Investigation of the Downstream Apoptotic Pathway in L929 and L929-11E Cells Upon Hyperthermia and TNF-a treatment --- p.142 / Chapter 3.8.1 --- Introduction --- p.142 / Chapter 3.8.2 --- Effect ofTNF-α and Hyperthermia on p53 Expression --- p.142 / Chapter 3.8.3 --- Effect of Hyperthermia and TNF-α on PARP --- p.146 / Chapter 3.8.4 --- Effect of Hyperthermia and TNF-α on Caspase-3 Activity --- p.149 / Chapter 3.8.5 --- Effect of Hyperthermia and TNF-α on Bid protein --- p.158 / Chapter 3.8.6 --- Effect of Hyperthermia and TNF-α on Caspase-8 Activity --- p.165 / Chapter 3.8.7 --- Effect ofTNF-α on TNFR1 Expression --- p.169 / Chapter Chapter 4. --- Discussion / Chapter 4.1 --- TNF-α Induced Apoptosis and Changed the Mitochondrial Activities in L929 Cells --- p.176 / Chapter 4.2 --- L929-11E cells Possessed Resistance Towards TNF-α --- p.187 / Chapter 4.3 --- Hyperthermia Triggered Apoptosis and Changed Mitochondrial Activities in L929 and L929-11E cells --- p.190 / Chapter 4.4 --- Combined hyperthermia and TNF-α treatment induced cell death and changed mitochondria activities in L929 and L929-11E cells --- p.195 / Chapter 4.5 --- Reversal of the TNF-α resistance and Enhancement of Sensitivity Towards Hyperthermia in L929-11E cells --- p.197 / Chapter 4.6 --- Proposed Pathway in the TNF-α- and Hyperthermia-mediated Apoptosis --- p.200 / Chapter 4.7 --- Application of TNF-α and Hyperthermia on Clinical Cancer Treatment --- p.203 / Chapter Chapter 5. --- Future Perspective of the Project --- p.206 / References --- p.210
62

Learning as participation in early clinical experience : its meaning for student physiotherapists

Hargreaves, Julian P. January 2014 (has links)
This research explores the meaning of learning as a process of social participation in clinical practice. The study focused on six first‐year student physiotherapists during a period of early clinical experience on a work integrated learning programme. The programme was unique at the time of the study in that it placed students in clinical settings from the first week of their undergraduate experience. The research applied a case study design and qualitative data were gathered from each student via on‐line learning journals, reflection lines and pre/post experience interviews. Data were analysed, between and within cases, to develop a sense of progressive narrative through the experiences made significant by each participant over the course of the clinical experience. An abductive logic was applied to develop a more theoretical explanation of learning as participation in clinical practice for each participant. The study concludes that these individuals adopted an agentic approach and recognised the benefit to their learning of proactively seeking opportunities to get involved in practice. Interaction with a range of co‐participants was valued, for a variety of reasons. Students were more willing to discuss their own deficits and ask questions of junior clinicians. Interactions with senior clinicians were more likely to challenge and extend the students' practice. Interactions with non‐physiotherapy colleagues in the multidisciplinary team were valued for the different perspectives they offered. Students valued participation in situations where they could assume greater responsibility, as long as their efforts were recognised by the clinical educator. Participants did not always see value in “routine” practice where there was little opportunity to be involved in decision making or discussion, describing their involvement as being “an extra pair of hands”. Participants described their performance of secondary Discourses of practice in the construction of their respective identities, which I describe as productive worker, trustworthy student, engaged student and junior professional. These Discourses supported participants' bids for recognition and progressive involvement in communities of clinical practice. However, where the participant identity was associated too strongly with a particular Discourse the educator could restrict access to learning opportunities. Participants dis‐identified themselves from Discourses that conflicted with individual habitus and conveyed lack of care or unethical behaviour. Where power relations challenged the possibility of overt rejection, participants were strategic and excluded these Discourses from their future, rather than current repertoires. At the start of their early clinical experience, participants expressed a desire to “learn by doing” and “learn on the job”. These cases demonstrate that even at an early stage of experience, participants were contributing to the productivity of the workplace and they felt valued when their contributions were recognised. These cases demonstrate that mutual relations support participation but require ongoing negotiation. Considering mutuality as a mechanism for participation in early clinical experience can support analysis of the ways in which social relations support both learning and work objectives. Mutuality as a mechanism for participation requires the learner and educator to recognise these dual objectives. Changing conditions of practice can threaten mutuality. Where a threat occurs, it is countered by adaptive practices that continue to support mutuality in terms of engagement, repertoire and enterprise with the community of clinical practice.
63

Tratamento de bacelos, sobrevivência de Xanthomonas campestris pv. viticola em tesouras de raleio, desinfestação desta ferramenta e de água utilizada na produção de mudas de videira

NAUE, Carine Rosa 22 February 2013 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2017-02-21T13:25:13Z No. of bitstreams: 1 Carine Rosa Naue.pdf: 1778234 bytes, checksum: 87c8b0b79d12b0deec69551209abe1ed (MD5) / Made available in DSpace on 2017-02-21T13:25:13Z (GMT). No. of bitstreams: 1 Carine Rosa Naue.pdf: 1778234 bytes, checksum: 87c8b0b79d12b0deec69551209abe1ed (MD5) Previous issue date: 2013-02-22 / The introduction and spread of grapevine bacterial canker caused by Xanthomonas campestris pv. viticola (Xcv) occurs, among other ways, through plantlets, grapevine cuttings and farming tools. This study aimed to: evaluate the effectiveness of treatments of cuttings to eradicate Xcv using thermotherapy, bactericides and sanitizers; prove the survival of Xcv into thinning shears; and select efficient sanitizers for disinfection of these tools and water used in the production of plantlets. In the first study, the Xcv isolates were tested for pathogenicity and "in vitro" sensitivity to bactericides and sanitizers (streptomycin+oxytetracycline, oxytetracycline+copper sulfate, kasugamycin and oxytetracycline; dodecyldimethyl ammonium chloride, sodium hypochlorite and benzalkonium chloride) at different concentrations. The eradication of Xcv on cuttings was tested in experiments with thermotherapy (50˚C for 30 and 40 min; 53˚C for 5 and 10 min); bactericides oxytetracycline+copper sulphate (150+2000, 165+2200, 180+2400 and 195+2600 mg L-1 of H2O) and oxytetracycline (600, 700, 800 and 900 mg L-1) and sanitizers dodecyldimethyl ammonium chloride (600, 1200, 1800, 2400, 3000 μl L-1) sodium hypochlorite (5000, 10000, 20000, 30000, 40000 μl L-1) and benzalkonium chloride (125, 167, 250, 334, 500 μl L-1). The bactericidal oxytetracycline and sanitizers dodecyldimethyl ammonium chloride and sodium hypochlorite provided the largest zones of inhibition, in vitro. However, it was not possible to recommend an efficient treatment of temperature/time, and concentrations of bactericides or sanitizers, among those tested, capable of eradicating Xcv of infected grapevine cuttings. In the second study, survival was evaluated 0-42 h after dipping the scissors in pathogen suspension. In vitro susceptibility test and initial selection in scissors were performed with the sanitizers dodecyldimethyl ammonium chloride (1200 μl L-1), sodium hypochlorite (20000 μl L-1), benzalkonium chloride (250 μl L-1), sodium dichloroisocyanurate (16.25 mg L-1), calcium hypochlorite (130 mg L-1), calcium oxychloride (97.5 mg L-1) and chlorine dioxide (25 μl L-1). To validate the efficiency of sanitizers for disinfection of scissors the first two products were tested at the same concentrations, and 50 cuts were sequentially made in vine leaves. The controls only with Xcv allow verifying the dissemination ability of Xcv from an inoculum source. The viability of the same sanitizers was studied 0-8 h after solution preparation. Disinfection of water contaminated with Xcv was tested with two bactericidal and three sanitizers. Xcv survived 24 h in thinning shears. Sodium hypochlorite (20000 μl L-1) and dodecyldimethyl ammonium chloride (1200 μl L-1) provided the greatest inhibition halos and disinfested scissors contaminated with Xcv. Solutions of these sanitizers remained viable for 8 h. Xcv was spread by contaminated thinning shears, on average, until the 24th cut. Disinfestation of the water contaminated with Xcv utilized in the plantlets production was obtained by dodecyldimethyl ammonium chloride (600 μl L-1), sodium hypochlorite (5000 μl L-1) and benzalkonium chloride (250 μl L-1). / A introdução e a disseminação do cancro bacteriano da videira causado por Xanthomonas campestris pv. viticola (Xcv) ocorre, dentre outras formas, por meio de mudas, bacelos e ferramentas de cultivo. Este trabalho teve como objetivos: avaliar a eficiência dos tratamentos de bacelos de videira para erradicação de Xcv utilizando termoterapia, bactericidas e sanitizantes; comprovar a sobrevivência de Xcv em tesouras de raleio; e selecionar sanitizantes eficientes para a desinfestação destas ferramentas e da água utilizada na produção de mudas. No primeiro trabalho, os isolados de Xcv foram testados quando à patogenicidade e realizado o teste de sensibilidade “in vitro” a bactericidas e sanitizantes (oxitetraciclina+estreptomicina, oxitetraciclina+sulfato de cobre, casugamicina e oxitetraciclina; cloreto de dodecildimetil amônio, hipoclorito de sódio e cloreto de benzalcônio) em diferentes concentrações. A erradicação de Xcv em bacelos de videira foi testada em experimentos com termoterapia (50oC por 30 e 40 min; 53oC por 5 e 10 min); bactericidas [oxitetraciclina+sulfato de cobre (150+2000, 165+2200, 180+2400 e 195+2600 mg L-1 de H2O) e oxitetraciclina (600, 700, 800 e 900 mg L-1)]; e sanitizantes [cloreto de dodecildimetil amônio (600, 1200, 1800, 2400, 3000 μL L-1); hipoclorito de sódio (5000, 10000, 20000, 30000, 40000 μL L-1) e cloreto de benzalcônio (125, 167, 250, 334, 500 μL L-1)]. O bactericida oxitetraciclina e os sanitizantes cloreto de dodecildimetil amônio e hipoclorito de sódio proporcionaram os maiores halos de inibição, in vitro. No entanto, não foi possível recomendar um tratamento termoterápico, bactericida ou sanitizante, dentre os testados, capaz de erradicar Xcv de bacelos de videira infectados. No segundo trabalho, a sobrevivência foi avaliada de 0 a 42 h após imersão das tesouras em suspensão do patógeno. Teste de sensibilidade de Xcv in vitro e seleção inicial em tesouras foram realizados com os sanitizantes cloreto de dodecildimetil amônio (1200 μl L-1), hipoclorito de sódio (20000 μl L-1), cloreto de benzalcônio (250 μl L-1), dicloroisocianurato de sódio (16,25 mg L-1), hipoclorito de cálcio (130 mg L-1), oxicloreto de cálcio (97,5 mg L-1) e dióxido de cloro (25 μl L-1). Para validação da eficiência dos sanitizantes na desinfestação de tesouras, os dois primeiros produtos foram testados nas mesmas concentrações, sendo realizados 50 cortes sequenciais, em folhas de videira. A testemunha com Xcv permitiu verificar a capacidade de disseminação de Xcv a partir da fonte de inóculo. A viabilidade dos sanitizantes foi estudada de 0 a 8 h após o preparo das soluções. Para desinfestação de água contaminada com Xcv foram testados 2 bactericidas e três sanitizantes. Xcv sobreviveu 24 h em tesouras de raleio. Hipoclorito de sódio (20000 μl L-1) e cloreto de dodecildimetil amônio (1200 μl L-1) proporcionaram os maiores halos de inibição e desinfestaram tesouras contaminadas com Xcv. As soluções destes sanitizantes mantiveram-se viáveis por 8 h. Xcv foi disseminada por tesouras de raleio contaminadas, em média, até o 24o corte. A desinfestação da água contaminada com Xcv utilizada na produção de mudas foi obtida pelo uso de cloreto de dodecildimetil amônio (600 μl L-1), hipoclorito de sódio (5000 μl L-1) e cloreto de benzalcônio (250 μl L-1).
64

Relações entre termoterapia, germinação, vigor e sanidade de sementes de tomate / Relationship between thermotherapy, germination, vigor and health of tomato seeds

Marcia Provinzano Braga 19 August 2009 (has links)
O presente trabalho objetivou estudar a relação da termoterapia com o potencial fisiológico e sanidade de sementes de tomate, imediatamente após o tratamento e durante o armazenamento, identificando combinações eficientes de temperatura e período de exposição através do teste de sanidade e testes de vigor. O trabalho, dividido em dois experimentos diferenciados pelos tratamentos e métodos de secagem, foi realizado nos laboratórios de Análise de Sementes do Departamento de Produção Vegetal e Patologia de Sementes do Departamento de Fitopatologia da USP-ESALQ e no Centro de Pesquisa Mokiti Okada M.O.A. No experimento I, sementes de dois lotes dos cultivares de tomate UC-82 e Rio Grande foram submetidas à termoterapia úmida com diferentes combinações de tempo e temperatura (52, 53, 54, 55 e 60°C/30 e 60 min), além das testemunhas (sementes tratadas com fungicida e não tratadas) e secadas ao ar livre por 72 horas. Após o tratamento as sementes tiveram seus desempenhos e sanidades avaliados em duas épocas, após a secagem e após 90 dias de armazenamento, através dos testes de porcentagem e primeira contagem de germinação, velocidade e porcentagem de emergência de plântulas, lixiviação de potássio, envelhecimento acelerado e sanidade. No experimento II, as sementes dos mesmos lotes foram submetidas à termoterapia nas combinações de tempo e temperatura de 55°C/30 min e 60°C/60 min, além das testemunhas, sementes tratadas com fungicida e não tratadas. Após o tratamento, as sementes foram cobertas com papel toalha e secadas por 12 horas e, em seguida, avaliadas através dos testes de sanidade, porcentagem e primeira contagem de germinação e envelhecimento acelerado. Os resultados permitiram concluir que a termoterapia (água quente a 55°C/30 min) é uma opção consistente para o controle de fungos associados às sementes de tomate, sem prejudicar o potencial fisiológico das sementes, dependendo da qualidade inicial do lote; os tratamentos 52 a 54°C por 30 ou 60 min não causam prejuízo ao potencial fisiológico de sementes de tomate, enquanto o efeito do tratamento a 55°C/60 min está associado à qualidade inicial do lote; o tratamento com água quente a 60°C por 30 ou 60 min não constitui opção para o tratamento de sementes de tomate, pois é eficiente para o controle de fungos, mas é letal às sementes; os tratamentos com água quente variando de 52 a 55°C por 30 ou 60 min não são eficientes em eliminar a bactéria Clavibacter michiganensis subsp. michiganensis e acarretam queda da resistência de sementes de tomate, tornando-as vulneráveis à manifestação dos sintomas de cancro bacteriano na plântula; o período de 90 dias de armazenamento em condições controladas (20°C e umidade relativa do ar de 50%) pode reduzir o potencial fisiológico de sementes de tomate tratadas com água quente, mas há necessidade de estudos adicionais com períodos maiores de armazenamento para obtenção de resultados mais consistentes; a termoterapia com água quente deixa as sementes de tomate vulneráveis à contaminação por fungos saprófitos, havendo necessidade de estudos adicionais para determinação de opções de tratamentos complementares que ofereçam efeito residual para evitar futuras contaminações, no armazenamento ou no substrato. / The research had as objective to investigate the relationship between thermotherapy and physiological potential and health of tomato seeds immediately after the treatment and during the storage period, then to identify efficient combinations between temperature and exposure time, through seed health test and seed vigor tests. The research was carried out at the Seed Analysis Laboratory of the Department of Vegetal Production and Seed Pathology Laboratory of Phytopathology Department of USP-ESALQ and at Mokichi Okada Research Center M.O.A.. and was divided in two experiments with different treatment and drying methods. In experiment I, seeds from two lots of UC-82 and Rio Grande tomato cultivars were submitted to humid thermotherapy with different combinations of time and temperature (52,53,54,55 and 60ºC/30 and 60 min.), besides the control treatment (seeds with fungicide treatment and without treatment) and dried at air during 72 hours. After the treatment, seeds were evaluated on their performances and seed health in two different periods (after drying and after 90 days storage), through percentage and first count of germination tests, speed and percentage of seedling emergence, potassium leachate, accelerated aging and seed health test. In experiment II, seeds from the same lots were submitted to thermotherapy under two combination of time and temperature (55ºC/30min and 60ºC/60min), besides the control treatment (seeds with fungicide treatment and without treatment). After treatment, seeds were covered with paper towel and dried during 12 hours, and then evaluated through seed health test, percentage and first count of germination tests and accelerated aging. The results lead to the conclusion that thermotherapy (hot water at 55ºC/30min) is a consistent option to control tomato seedborne fungi, without damaging the physiological potential of the seeds, depending on the initial quality of the seeds lots. Treatments with hot water at 52 to 54ºC during 30 to 60 min do not cause damage to tomato seeds physiological potential, while 55ºC/60 min treatment results are associated with the initial quality of the lots. The treatment with hot water at 60ºC during 30 or 60 min cannot be considered as an option because is very effective to control fungi, otherwise is lethal to the seeds. The treatments with hot water temperature between 52 and 55ºC during 30 or 60 minutes were not effective to eradicate Clavibacter michiganensis subsp. michiganensis and caused the fall of the tomato seed resistance to diseases, turning the seeds vulnerable to bacterial canker symptoms show up in the seedling. Ninety days storage period under controlled conditions (20ºC and relative humidity of 50%) may reduce physiological potential of the hot water treated seeds, but further investigation is needed with longer periods of storage to obtain more consistent results. Thermotherapy with hot water make the tomato seeds more vulnerable to saprophytic fungi contamination, needing additional studies to define the options of complementary treatments that offer residual effect to avoid future contaminations, during storage and in the substrate.
65

Termoterapia associada à cultura de tecidos para obtenção de plantas de cana-de-açúcar da variedade SP80-3280 livres de Leifsonia xyli subsp. xyli / Thermotherapy associated to tissue culture to obtain sugarcane plants of variety SP80-3280 free from Leifsonia xyli subsp. xyli

Chaddad, Martha Monteiro 15 April 2013 (has links)
A cana-de-açúcar é uma das principais culturas agroindustriais do Brasil. Como outras culturas de importância econômica, é também afetada por diversos patógenos como fungos, bactérias, vírus e fitoplasmas que podem limitar sua produção. A bactéria fastidiosa Leifsonia xyli subsp. xyli (Lxx) é o agente causal do raquitismo-da-soqueira da cana-de-açúcar (RSD). Esta doença não apresenta sintomas externos característicos de fácil reconhecimento. Dessa forma, a incidência do RSD pode não ser perceptível durante inspeções visuais de campo e, assim, ser facilmente disseminado de uma região para outra. A bactéria restrita ao xilema é transmitida mecanicamente de plantas infectadas para plantas saudáveis por meio da seiva presente em ferramentas de corte e em outros equipamentos durante o plantio, o cultivo e a colheita da cultura. Em razão da importância da cana-de-açúcar e do dano causado por Lxx, este trabalho visou avaliar a termoterapia e o cultivo in vitro em dois experimentos direcionados à obtenção de plantas de cana-de-açúcar da variedade SP80-3280 livres de Leifsonia xyli subsp. xyli e, assim, fornecer subsídio para o aprimoramento das medidas atuais de controle. O primeiro experimento combinou a termoterapia de toletes de uma gema (52 °C por 30 minutos) com o cultivo de meristemas apicais de três tamanhos (0,5 mm, 1,0 mm e 1,5 mm); o segundo combinou três tempos de termoterapia (1 hora, 2 horas e 3 horas) a 50 °C em gemas laterais imaturas isoladas do tolete com o cultivo in vitro. No primeiro experimento, os resultados de RT-PCR das amostras coletadas aos 15 dias na casa de vegetação mostraram que os três tamanhos de meristemas produziram plantas com títulos bacterianos em média 25 vezes mais baixos que suas genitoras, mas não as isentaram completamente de Lxx, com exceção de 8 plantas que não apresentaram Lxx com 90 dias de cultivo (4 plantas provenientes do cultivo de meristemas de 0,5 mm, 1 planta de meristema de 1,0 mm e 3 plantas de meristemas de 1,5 mm). Além disso, os meristemas de 0,5 mm não necessariamente regeneraram plantas com títulos mais baixos da bactéria quando comparados com os meristemas de 1,0 mm e 1,5 mm, mostrando que estes tamanhos testados não apresentaram correlação direta com o nível de infecção da planta regenerada por eles. Em relação ao segundo experimento, os resultados de RT-PCR mostraram que o incremento no tempo de termoterapia proporcionou maior redução nos títulos bacterianos, sendo os tratamentos de 2 horas e 3 horas os mais bem sucedidos com média de redução de 80,08% e 81,73%, respectivamente, mas não foi capaz de eliminar a bactéria. Portanto, estes experimentos demonstram que a termoterapia associada ao cultivo de tecidos é uma metodologia promissora, pois apresentaram redução da presença da bactéria Lxx em plantas de cana-de-açúcar, mas por não terem sido totalmente efetivos na eliminação da mesma, reforça a necessidade de estudos complementares. / Sugarcane is one of the major agro-industrial crops of Brazil. Like other crops of economic importance, it\'s also affected by several pathogens such as fungus, bacteria, viruses and phytoplasmas that may limit its production. The fastidious bacterium Leifsonia xyli subsp. xyli (Lxx) is the causal agent of ratoon stunting disease in sugarcane (RSD). This disease shows no external symptoms characteristic of easy recognition. Thus, the incidence of RSD may not be noticeable during visual inspection in the field and be easily spread from one region to another. The xylem-limited bacterium is transmitted mechanically from infected plants to healthy plants by the sap present in cutting tools and others equipments for planting, growing and harvesting the crop. Due to the importance of sugarcane and the damage caused by Lxx, this work aimed to evaluate thermotherapy and in vitro culture in two experiments in order to obtain sugarcane plants of variety SP80-3280 free from Leifsonia xyli subsp. xyli and thus provide subsidy for the improvement of current control methods. The first experiment combined thermotherapy on the individual bud (52 °C for 30 minutes) and the cultivation of apical meristems of three sizes (0,5 mm, 1,0 mm and 1,5 mm); the second combined three period of thermotherapy (1 hour, 2 hours and 3 hours) at 50 °C in immature lateral buds totally isolated from the tissue source followed by in vitro culture. In the first experiment, the results of RT-PCR samples collected at 15 days in the greenhouse showed that the three sizes of meristems produced plants with bacterial titers on average 25 times lower than their mother plants, but not completely exempted them from Lxx, except 8 plants that showed no Lxx after 90 days of cultivation (4 plants were from cultivation of meristems with 0,5 mm, 1 plant from 1,0 mm meristem and 3 plants from 1,5 mm meristems size). Furthermore, the meristems of 0,5 mm does not necessarily regenerate plants with lower title of the bacteria compared with the meristems of 1.0 mm and 1.5 mm, showing that these sizes tested did not present direct correlation with the level of infection on the plants regenerated from them. Regarding the second experiment, RT-PCR results showed that the increase in time of thermotherapy provided greater reduction in bacterial titers, and the treatments of 2 and 3 hours were the most successful with average reduction of 80,08 % and 81,73%, respectively, but was not able to eliminate the bacteria. Therefore, these experiments showed that thermotherapy associated with tissue culture is a promising methodology because it reduced titer of Lxx in sugarcane, but were not fully effective in eliminating the same, reinforcing the need for complementary studies.
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Extratos de brássicas e termoterapia no controle de podridão parda em pós-colheita de pêssego

Pazolini, Kelly 18 December 2014 (has links)
CAPES / A podridão parda (Monilinia fructicola) é uma das principais doenças das frutas de caroço, causando perdas em pré e pós-colheita. Os objetivos deste estudo foram avaliar diferentes formas de extração dos extratos de canola e de mostarda-da-índia sobre a podridão parda, avaliar a melhor forma de aplicação dos extratos dessas plantas associados à termoterapia sobre podridão parda e comparar o melhor resultado desses estudos com o controle químico. Inicialmente foram realizados testes com diferentes formas de extração dos extratos de canola e mostarda-da-índia. Para isso, as espécies de brássicas foram cultivadas e coletadas em pleno florescimento, secas em estufa e trituradas, para obtenção de um pó. Para o modo de extração simples, o pó foi misturado à água e filtrado. Para extração por maceração, o extrato foi filtrado somente após um tempo de reserva de 8 horas. Para extração por infusão utilizou-se água aquecida a 100 °C e, após 20 minutos a solução foi filtrada. Os extratos simples de cada planta foram selecionados para serem testados em diferentes combinações de tratamentos com a termoterapia por imersão em água quente (50 °C por 30 s). Os tratamentos testados, para canola e mostarda-da-índia, foram: 1- Aplicação do respectivo extrato e inoculação dos frutos (EI); 2- Frutos inoculados e aplicação do respectivo extrato (IE); 3- Inoculação dos frutos e aplicação da termoterapia (IT); 4- Aplicação do respectivo extrato, inoculação dos frutos e aplicação da termoterapia (EIT); 5- Inoculação dos frutos, aplicação da termoterapia e aplicação do extrato (ITE); 6- Aplicação do respectivo extrato, inoculação dos frutos, aplicação da termoterapia e aplicação do extrato novamente (EITE) e 7- Pêssegos inoculados e tratados com água esterilizada (testemunha). Os tratamentos EITE de canola e mostarda-daíndia foram selecionados para serem comparados com o tratamento químico (azoxystrobin®, 2 g L-1). Todas as formas de extração testadas, das duas espécies de brássica, reduziram significativamente o crescimento micelial e germinação de conídios de M. fructicola, e a área da lesão de podridão parda e produção de conídios in vivo, exceto o extrato de mostarda-daíndia por infusão que não reduziu a área da lesão de podridão parda. Os tratamentos EITE de canola e mostarda-da-índia foram mais eficientes no controle da podridão parda em pêssego, reduzindo a doença, em média, 58 e 51%, respectivamente. Quando os tratamentos foram comparados entre si e com o controle químico, observou-se que o tratamento EITE de canola foi superior ao tratamento EITE de mostarda-da-índia e não diferiu do controle químico sobre a produção de conídios nas lesões de podridão parda em pêssego, diminuindo a área da lesão em mais de 84%, e a esporulação em mais de 90%. A aplicação de extrato simples de canola, seja aplicado sozinho ou na tática EITE, se apresenta como uma alternativa eficiente e práticas no controle da podridão parda em pós-colheita de pêssego. / Brown rot (Monilinia fructicola) is the major disease of stone fruits, causing pre and postharvest losses. The objectives of this study were to evaluate different forms of extraction of canola and indian mustard extracts to control brown rot, assess the best way of application of extracts of these plants associated with thermotherapy to control brown rot and compare the best result of these studies with chemical control. Initially, tests were made with different forms of extraction of canola and indian mustard extracts. For this, brassica species were collected in full bloom, oven dried and ground to obtain a powder. For the simple extraction mode, the powder was mixed with water and filtered. For maceration extraction, the extract was filtered only after a time of 8 hours of booking. To infusion extract, was used water heated to 100 °C and after 20 min the solution was filtered. Simple extracts from each plant were selected to be tested in different combinations with the thermotherapy treatment by immersion in hot water (50 °C for 30 s). The treatments tested for canola and indian mustard were: 1- Application of the respective extract and inoculation of fruits (EI); 2- inoculated fruits and implementation of its extract (IE); 3- Inoculation of fruit and application of thermotherapy (IT); 4- Application of the respective extract, inoculation of fruits and application of thermotherapy (EIT); 5- Inoculation of fruit, application of thermotherapy and application of the extract (ITE); 6- Application of the respective extract, inoculation of fruits, application of thermotherapy and application of the extract again (EITE) and 7- inoculated peaches and treated with sterile water (control). The EITE with treatments canola and indian mustard were selected for comparison with chemical treatment (azoxystrobin®, 2 g L-1). All tested extraction, of the two species of brassica, significantly reduced the mycelial growth and conidial germination of M. fructicola, and the area of brown rot injury and conidia production in vivo, except the extraction infusion of indian mustard, that did not reduce the area of brown rot injury. The EITE treatments of canola and indian mustard were more efficient in controlling brown rot in peach, reducing the disease, on average, 58 and 51%, respectively. When the treatments were compared with chemical control, were observed that canola EITE treatment was superior to indian mustard EITE treatment, and did not differ from chemical control on the production of conidia in brown rot lesions in peach, reducing the area of the lesion in more than 84% and sporulation in more than 90%. The application of simple canola extract, whether used alone or in EITE tactic, is an efficient alternative in the control of brown rot in peach postharvest. / 5000
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Puxamento de fibras cristalinas do sistema Al2O3-Nd2O3 e o desenvolvimento de ponta cristalina para aplicação em termoterapia pontual a quente / Crystal fibers pulling from the Al2O3-Nd2O3 system and the development of crystal tip for application in punctual hot thermotherapy

Sergio Paulo Marcondes 30 May 2014 (has links)
A radiação laser tem sido amplamente utilizada em diversos dispositivos para aplicações tecnológicas. Uma área particularmente interessante que tem sido explorada para o desenvolvimento destes dispositivos é a medicina. Um campo da medicina que tem se beneficiado desse esforço é a termoterapia a laser. No entanto, algumas desvantagens do uso em larga escala desta tecnologia são devidas à falta de uniformidade da absorção da radiação pelo tecido humano. Uma maneira proposta de resolver esta problemática tem sido a utilização de um método fototérmico indireto para converter a energia da luz do laser em calor; por meio de uso de pontas de fibras ópticas revestidas. Contudo, o uso dessas pontas apresenta a desvantagem da limitada estabilidade química do revestimento. Neste trabalho, apresentamos os resultados do desenvolvimento de pontas cristalinas de Nd2O3 altamente estáveis quimicamente em fibras monocristalinas de safira (Al2O3) obtidas diretamente a partir da fase líquida (fundida), fazendo-se uso da técnica Laser-Heated Pedestal Growth (LHPG). A metodologia desenvolvida permite a produção de pontas de diâmetros variados, o que possibilita definir a dimensão da região de aquecimento dentro dos limites de interação ponta cristalina/meio. Para o crescimento dos cristais no formato de fibras, chamados de fibras monocristalinas, usando-se a técnica LHPG, preparamos pedestais de Al2O3 puros e de composição Nd2O3, utilizando-se a técnica de extrusão a frio. Fibras monocristalinas de safira de 0,67 mm de diâmetro e 200 mm de comprimento, livres de poros ou trincas, com pontas cristalinas aproximadamente cônicas foram fabricadas em atmosfera aberta. Para avaliarmos a eficiência da conversão de luz em calor, as fibras foram bombeadas com luz de um laser de comprimento de onda 810 nm. Uma correspondência linear entre a potência do laser e a temperatura da ponta cristalina foi determinada em nossos sistemas e valores de até 250 oC podem ser alcançados; o que torna a ponta cristalina da fibra promissora para aplicações em termoterapia a laser e para a área de soldagem em micro(nano) eletrônica. Neste trabalho apresentamos também um estudo sistemático sobre o processo de puxamento de fibras do compósito eutético Nd2O3-NdAl11O18, através da técnica LHPG, com velocidades de puxamento variando entre 0,08 - 0,92 mm/min. As fibras eutéticas foram fabricadas com sucesso, livres de poros ou trincas. A microestrutura analisada ao microscópio eletrônico de varredura (MEV) foi denominada como do tipo regular, presente em todas as amostras. A despeito da sua complexidade, a microestrutura desse compósito foi controlada e a relação entre o espaçamento médio entre as fases e a velocidade de puxamento &#9552v = constante = (8,2 ± 0,3) µm3/s foi mantida em todo o intervalo das velocidade de puxamento utilizadas. Devido às propriedades mecânicas e ópticas das fases eutéticas individuais, este compósito apresenta-se como candidato com enorme potencial para aplicações dentro da ciência e engenharia de materiais. Ao nosso conhecimento, este trabalho parece ser o primeiro relato sobre a microestrutura eutética do sistema binário Al2O3-Nd2O3. / The laser radiation has been extensively used as devices for technological application, for which the medicine is a hot topic. In this field, the laser-induced thermotherapy is the primary beneficiary of the main researches and applications. However, the heterogeneity associated to the light aborsorption by the human tissue is major impediment preventing the large using of the thermotherapy. To solve this situation, an indirect photothermal method has been employed in order to convert laser radiation into heat by using coated optical fiber tips. Nevertheless, the limited chemical stability of the coating is a crucial problem associated to the large scale application of these coated tips. In the present work, we prepared crystal tips of Nd2O3, chemically stable, coupled in the Al2O3 (sapphire) crystal fiber, being both obtained by the laser-heated pedestal growth technique (LHPG), providing the production of tips with different diameters. Also, the cold extrusion technique was employed to produce the Al2O3 e Nd2O3 pedestals. Besides, the Al2O3 crystal fibers with 0.67 mm in diameter and 200 mm in length, free of cracks and pores, were successfully produced in an air atmosphere. In order to account the efficiency of the light-to-heat conversion, the fibers were pumped with laser light centered at 810 nm. Finally, linear correspondence between laser power and crystal tip temperature was determined in our systems, making them appropriated to the laser-induced thermotheraphy applications and welding in micro- and nano-electronics. Furthermore, we presented a profound investigation about the pulling process of Nd2O3-NdAl11O18 eutectic fibers obtained by LHPG technique. These eutectics were successfully pulled free of cracks and pores. Using scanning electron microscopy (SEM), we were capable of identificating the regular microstructure of our eutectics. Changes in the microstructure were observed in the eutectic fibers pulled using fiber pulling rates from 0.08 to 0.92 mm/min. Despite the complexity of their microstructures, the relation &#9552v = (8,2 ± 0,3) µm3/s = constant, defined by Jackson and Hunt, applied very well for this system. Owing to the mechanical and optical properties of the eutectic phases, these compounds present huge potential for applications in the materials science and engineering related fields. To our knowledge, this work seems to be the first report on the eutectic microstructure of the Al2O3-Nd2O3 binary system.
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Termoterapia associada à cultura de tecidos para obtenção de plantas de cana-de-açúcar da variedade SP80-3280 livres de Leifsonia xyli subsp. xyli / Thermotherapy associated to tissue culture to obtain sugarcane plants of variety SP80-3280 free from Leifsonia xyli subsp. xyli

Martha Monteiro Chaddad 15 April 2013 (has links)
A cana-de-açúcar é uma das principais culturas agroindustriais do Brasil. Como outras culturas de importância econômica, é também afetada por diversos patógenos como fungos, bactérias, vírus e fitoplasmas que podem limitar sua produção. A bactéria fastidiosa Leifsonia xyli subsp. xyli (Lxx) é o agente causal do raquitismo-da-soqueira da cana-de-açúcar (RSD). Esta doença não apresenta sintomas externos característicos de fácil reconhecimento. Dessa forma, a incidência do RSD pode não ser perceptível durante inspeções visuais de campo e, assim, ser facilmente disseminado de uma região para outra. A bactéria restrita ao xilema é transmitida mecanicamente de plantas infectadas para plantas saudáveis por meio da seiva presente em ferramentas de corte e em outros equipamentos durante o plantio, o cultivo e a colheita da cultura. Em razão da importância da cana-de-açúcar e do dano causado por Lxx, este trabalho visou avaliar a termoterapia e o cultivo in vitro em dois experimentos direcionados à obtenção de plantas de cana-de-açúcar da variedade SP80-3280 livres de Leifsonia xyli subsp. xyli e, assim, fornecer subsídio para o aprimoramento das medidas atuais de controle. O primeiro experimento combinou a termoterapia de toletes de uma gema (52 °C por 30 minutos) com o cultivo de meristemas apicais de três tamanhos (0,5 mm, 1,0 mm e 1,5 mm); o segundo combinou três tempos de termoterapia (1 hora, 2 horas e 3 horas) a 50 °C em gemas laterais imaturas isoladas do tolete com o cultivo in vitro. No primeiro experimento, os resultados de RT-PCR das amostras coletadas aos 15 dias na casa de vegetação mostraram que os três tamanhos de meristemas produziram plantas com títulos bacterianos em média 25 vezes mais baixos que suas genitoras, mas não as isentaram completamente de Lxx, com exceção de 8 plantas que não apresentaram Lxx com 90 dias de cultivo (4 plantas provenientes do cultivo de meristemas de 0,5 mm, 1 planta de meristema de 1,0 mm e 3 plantas de meristemas de 1,5 mm). Além disso, os meristemas de 0,5 mm não necessariamente regeneraram plantas com títulos mais baixos da bactéria quando comparados com os meristemas de 1,0 mm e 1,5 mm, mostrando que estes tamanhos testados não apresentaram correlação direta com o nível de infecção da planta regenerada por eles. Em relação ao segundo experimento, os resultados de RT-PCR mostraram que o incremento no tempo de termoterapia proporcionou maior redução nos títulos bacterianos, sendo os tratamentos de 2 horas e 3 horas os mais bem sucedidos com média de redução de 80,08% e 81,73%, respectivamente, mas não foi capaz de eliminar a bactéria. Portanto, estes experimentos demonstram que a termoterapia associada ao cultivo de tecidos é uma metodologia promissora, pois apresentaram redução da presença da bactéria Lxx em plantas de cana-de-açúcar, mas por não terem sido totalmente efetivos na eliminação da mesma, reforça a necessidade de estudos complementares. / Sugarcane is one of the major agro-industrial crops of Brazil. Like other crops of economic importance, it\'s also affected by several pathogens such as fungus, bacteria, viruses and phytoplasmas that may limit its production. The fastidious bacterium Leifsonia xyli subsp. xyli (Lxx) is the causal agent of ratoon stunting disease in sugarcane (RSD). This disease shows no external symptoms characteristic of easy recognition. Thus, the incidence of RSD may not be noticeable during visual inspection in the field and be easily spread from one region to another. The xylem-limited bacterium is transmitted mechanically from infected plants to healthy plants by the sap present in cutting tools and others equipments for planting, growing and harvesting the crop. Due to the importance of sugarcane and the damage caused by Lxx, this work aimed to evaluate thermotherapy and in vitro culture in two experiments in order to obtain sugarcane plants of variety SP80-3280 free from Leifsonia xyli subsp. xyli and thus provide subsidy for the improvement of current control methods. The first experiment combined thermotherapy on the individual bud (52 °C for 30 minutes) and the cultivation of apical meristems of three sizes (0,5 mm, 1,0 mm and 1,5 mm); the second combined three period of thermotherapy (1 hour, 2 hours and 3 hours) at 50 °C in immature lateral buds totally isolated from the tissue source followed by in vitro culture. In the first experiment, the results of RT-PCR samples collected at 15 days in the greenhouse showed that the three sizes of meristems produced plants with bacterial titers on average 25 times lower than their mother plants, but not completely exempted them from Lxx, except 8 plants that showed no Lxx after 90 days of cultivation (4 plants were from cultivation of meristems with 0,5 mm, 1 plant from 1,0 mm meristem and 3 plants from 1,5 mm meristems size). Furthermore, the meristems of 0,5 mm does not necessarily regenerate plants with lower title of the bacteria compared with the meristems of 1.0 mm and 1.5 mm, showing that these sizes tested did not present direct correlation with the level of infection on the plants regenerated from them. Regarding the second experiment, RT-PCR results showed that the increase in time of thermotherapy provided greater reduction in bacterial titers, and the treatments of 2 and 3 hours were the most successful with average reduction of 80,08 % and 81,73%, respectively, but was not able to eliminate the bacteria. Therefore, these experiments showed that thermotherapy associated with tissue culture is a promising methodology because it reduced titer of Lxx in sugarcane, but were not fully effective in eliminating the same, reinforcing the need for complementary studies.
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Controle físico e biológico de Fusarium oxysporum f. sp. zingiberi em gengibre / Physical and biological control of Fusarium oxysporum f. sp. zingiberi in ginger

Fernanda Domingues 19 April 2006 (has links)
O Amarelo ou Murcha de Fusarium, causado por Fusarium oxysporum f. sp. zingiberi vem assumindo grande importância na cultura do gengibre devido à ausência de métodos eficientes de controle. Com os objetivos de testar a termoterapia associada ao tratamento químico e biológico para a obtenção de rizomas-semente sadios e avaliar a indução de supressividade do solo a Fusarium oxysporum f. sp. zingiberi com a incorporação de casca de camarão, seis ensaios foram conduzidos. Para o tratamento térmico, foram utilizados rizomas infectados, com aproximadamente 5cm de comprimento. As relações tempo-temperatura utilizadas foram: 45°C por zero, 60, 120 e 180 minutos e 50°C por zero, dez e 20 minutos (ensaio 1 e campo); 50°C por zero, 30 e 60 minutos e 55°C por zero, 10 e 20 minutos (ensaio 2); 50, 55 e 60ºC por zero, 10 e 20 min (ensaio 3). As caldas para tratamento térmico foram constituídas por água, solução de tiofanato metílico e caldo fermentado por Bacillus subtilis. No experimento em laboratório, os rizomas foram inoculados artificialmente. Após uma semana, receberam o tratamento térmico a 45º C por 60, 120 e 180 minutos e a 50ºC e 55ºC por 10e 20 minutos. Após a termoterapia, segmentos de rizoma foram plaqueados, sendo avaliados pela contagem dos segmentos que apresentavam o crescimento do patógeno. Na coleta, foram avaliadas altura, peso da matéria fresca da parte aérea e produção, e realizado o plaqueamento da parte aérea, raiz e rizoma. Para verificar a possibilidade do uso de casca de camarão, o solo foi infestado com o isolado patogênico. Após uma semana, houve a incorporação da casca de camarão ao solo nas concentrações de 0; 2,5; 5; 7,5; 10; 15 e 20% (v/v). A população de Fusarium do solo e a comunidade de actinomicetos foram avaliadas semanalmente por diluição em série e plaqueamento. Após oito semanas da incorporação, foi realizado o plantio de um rizoma-semente de gengibre por vaso. Na coleta, a avaliação foi realizada da mesma maneira que para termoterapia. Através de todos os resultados obtidos nos cinco ensaios de termoterapia, verificouse a possibilidade de utilização da técnica com sucesso no auxílio ao controle da doença. As melhores combinações tempo/temperatura foram a 45ºC pelo tempo de 120 minutos ou a 55ºC por 20 minutos em todas as caldas. No teste com o uso da casca de camarão, houve uma diminuição da população de Fusarium e aumento da comunidade de actinomicetos nos solos que receberam a incorporação de casca. A adição de casca de camarão ao solo permite o plantio do gengibre em locais onde o patógeno esteja presente. / Yellow or Fusarium Wilt, caused for Fusarium oxysporum f. sp. zingiberi comes assuming great importance in the culture of the ginger due to absence of efficient methods of control. With the objectives to test the thermotherapy associated with the chemical and biological treatment for the healthy attainment of ginger-seed and to evaluate the induction of soil suppressiveness to Fusarium oxysporum f. sp. zingiberi with the incorporation of shrimp peel, six experiments had been lead. For the thermal treatment, infested rhizome had been used, with approximately 5cm of length. The used relations time-temperature had been: 45°C for zero, 60, 120 and 180 minutes and 50°C for zero, ten and 20 minutes (experiment 1 and field); 50°C for zero, 30 and 60 minutes and 55°C for zero, 10 and 20 minutes (experiment 2); 50, 55 and 60ºC for zero, 10 and 20 min (experiment 3). Solutions for thermal treatment had been constituted by water, solution of thiophanate methylic and broth leavend for Bacillus subtilis. In the experiment in laboratory, rhizomes had been inoculated artificially. After one week, they had received the thermal treatment 45º C for 60, 120 and 180 minutes and 50ºC and 55ºC for 10 and 20 minutes. After the thermal treatment, segments of rhizomes had been placed in plates, being evaluated for the counting of the segments that presented the growth of the pathogen. In the collection, height, weight of the aerial part and production had been evaluated, and carried through plating of the aerial part, root and rhizome. To verify the possibility of the use of shrimp peel, the soil was infested with isolated the pathogenic one. After one week, had the incorporation of the peel of shrimp to the soil in the concentrations of 0; 2,5; 5; 7,5; 10; 15 and 20% (v/v). The population of Fusarium of the soil and the community of actinomycetes had been evaluated weekly by dilution in series and placed in plates. After eight weeks of the incorporation, the plantation of one rizome-seed of ginger for vase was carried through. In the collection, the evaluation was carried through in the same way that for thermotherapy. Through all the results gotten in the five experiments of thermotherapy, it was verified successfully possibility of use of the technique in the aid to the control of the illness. The best combinations time/temperature had been 45ºC for the time of 120 minutes or 55ºC per 20 minutes in all solutions. In the test with the use of the shrimp peel, it had a reduction of the population of Fusarium and increase of the community of actinomycetes in the soil that had received the incorporation from peel. The addition of peel of shrimp to the soil allows the plantation of the ginger in places where the pathogen is present.
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Změny centrální reaktibility v průběhu termické stimulace monitorované pomocí elektromagnetické tomografie (sLORETA) / Changes in central reactibility during thermal stimulation monitored by electromagnetic tomography (sLORETA)

Richtrová, Eva January 2020 (has links)
Title: Changes in central reactivity during thermal stimulation monitored by electromagnetic tomography (sLORETA) Objectives: The objective of this thesis is to determine whether there are any changes in central reactivity during local thermal stimulation by heat and cold and to compare the effect of analgesic electrical stimulation by TENS (Transcutaneous Electrical Nerve Stimulation) applied after single thermal stimuli. The brain activity was scanned from the scalp EEG and the results were evaluated by using sLORETA program. Methods: Twelve young, healthy people over the age of 21 participated in this study. The requirement for the participation in this experiment was good health condition without any neurological or other diagnoses. The electrical activity of the brain was being recorded throughout the whole experiment using a 32-channel EEG cap. The measurement had multiple parts. During the whole experiment, the participants were lying on the therapeutic table and all stimuli were applied locally to the right hand. Firstly, the EEG was recorded while participants were resting with closed eyes for five minutes. Then we realized a measurement of a two-minute long application of electrical stimulation of TENS in above-threshold sensitive intensity, which was individual for each participant. The...

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