In the field of regenerative medicine, there is a need to develop technologies that can increase the overall efficiency of imaging and expanding cells in culture and in complex heterogeneous arrangements necessary for tissue construction. Long-term live cell imaging has the potential to significantly enhance our understanding of intercellular signaling pathways and the dependence of phenotype on cell arrangement. A transdisciplinary approach has been taken to bridge the fields of cell biology, robotics, and photonics to create a long-term live cell imaging system capable of single cell handling as well as the acquisition of multiple types of data needed for data mining and a general informatics approach to cell culture. A Bio-Assembly Mosaic Builder and Informatics (BAMBI) system was designed and developed using custom software to control a 3-axis stage manufactured by Galil Inc, and custom 1-axis micromanipulator for robotic operations. The software also employs a Sony charged-coupled device sensor for real-time image feedback and data acquisition. The system is mounted on a Carl Zeiss Axiovert 200 inverted microscope. Custom-built environmental controls are used to maintain the temperature, humidity, and gas conditions for extended live cell work. The software was designed using Visual C++ for the Windows PC platform using an object orientated and modular design methodology to allow the BAMBI software to continue to grow with new tasks and demands as needed. The modular approach keeps functional groups of code within context boundaries allowing for easy removal, addition, or changes of functions without compromising the usability of the whole system. BAMBI has been used to image cells within a novel cell culture chamber that constricts cell growth to a true monolayer for high-resolution imaging. In one specific application, BAMBI was also used to characterize and track the development of individual Colony Forming Units (CFU) over the five-day culture period in 5-day CFU-Hill colony assays. The integrated system successfully enabled the tracking and identification of cell types responsible for the formation of the CFU-Hill colonies (a putative endothelial stem cell). BAMBI has been used to isolate single hematopoietic stem cell (HSC) candidate cells, accumulate long-term live cell images, and then return these cells back to the in-vivo environment for further characterization. From these results, further data mining and lineage informatics suggested a novel way to isolate and purify HSCs. Studies such as these are the fundamental next step in developing new therapies for regenerative medicine in the future.

In the field of regenerative medicine, there is a need to develop technologies that can increase the overall efficiency of imaging and expanding cells in culture and in complex heterogeneous arrangements necessary for tissue construction. Long-term live cell imaging has the potential to significantly enhance our understanding of intercellular signaling pathways and the dependence of phenotype on cell arrangement. A transdisciplinary approach has been taken to bridge the fields of cell biology, robotics, and photonics to create a long-term live cell imaging system capable of single cell handling as well as the acquisition of multiple types of data needed for data mining and a general informatics approach to cell culture. A Bio-Assembly Mosaic Builder and Informatics (BAMBI) system was designed and developed using custom software to control a 3-axis stage manufactured by Galil Inc, and custom 1-axis micromanipulator for robotic operations. The software also employs a Sony charged-coupled device sensor for real-time image feedback and data acquisition. The system is mounted on a Carl Zeiss Axiovert 200 inverted microscope. Custom-built environmental controls are used to maintain the temperature, humidity, and gas conditions for extended live cell work. The software was designed using Visual C++ for the Windows PC platform using an object orientated and modular design methodology to allow the BAMBI software to continue to grow with new tasks and demands as needed. The modular approach keeps functional groups of code within context boundaries allowing for easy removal, addition, or changes of functions without compromising the usability of the whole system. BAMBI has been used to image cells within a novel cell culture chamber that constricts cell growth to a true monolayer for high-resolution imaging. In one specific application, BAMBI was also used to characterize and track the development of individual Colony Forming Units (CFU) over the five-day culture period in 5-day CFU-Hill colony assays. The integrated system successfully enabled the tracking and identification of cell types responsible for the formation of the CFU-Hill colonies (a putative endothelial stem cell). BAMBI has been used to isolate single hematopoietic stem cell (HSC) candidate cells, accumulate long-term live cell images, and then return these cells back to the in-vivo environment for further characterization. From these results, further data mining and lineage informatics suggested a novel way to isolate and purify HSCs. Studies such as these are the fundamental next step in developing new therapies for regenerative medicine in the future.

Made available in DSpace on 2016-06-02T19:48:26Z (GMT). No. of bitstreams: 1 6683.pdf: 1309691 bytes, checksum: a89d34d3628e54a7f9ed01c34014ad28 (MD5) Previous issue date: 2015-02-26 / This work entitled "The search for natural childbirth and motivations to prepare the pelvic diaphragm with the epi-no" has as main objectives: to understand the elements involved in the choice of women for natural childbirth, identify motivations for the preparation of the pelvic diaphragm with the epi-no, seeking natural childbirth and identify the components that facilitate and those that hinder this choice. Was carried out with women who were part of the Epi-no Program, Health Laboratory initiative of Women of University of São Paulo, between 2013 and 2014. This is a qualitative research, for which we used as theoretical and methodological approach, Feminism Dialogic proposed by Lygia Puigvert (2001) and the Critical Communicative Methodology (MCC) proposed by Gomez et al (2006), both anchored in theoretical frameworks of Dialogic Learning, which in turn are based on concept of Communicative Action Habermas (1999) and dialogical of Paulo Freire (1994; 2005). The MCC seeks to identify the transformative dimensions, that is, those that promote or facilitate, in this case, a pleasurable experience of childbirth and cause difficulties dimensions, that is, those that represent a barrier to this experience, both relating to the categories of life and world system. Data collection began in November / 2013, and the analysis was organized as the basic level of analysis proposed by the MCC. Eight women were interviewed, seven of them completed the two phases of the communicative account, according to the methodology and there was canceling an interview, due to loss of material. The women were between 22 and 38 years with predominance of age above 30 years, all had a partner, five were primiparous (1st pregnancy) and two multiparous (2 or more pregnancies), with a history of cesarean section and abortion and all performed in childbirth hospital environment. The results showed that the discovery of pregnancy urged to talk with family, friends and health professionals about natural childbirth; aroused the personal search for information (books, magazines, internet, support groups natural childbirth); motivated to prepare the pelvic diaphragm with epi-no, among others. Childbirth, previously seen as traumatic and surrounded interventions (oxytocin, episiotomy, Kristeller) and suffering, in general gained a new meaning, exchanging a traumatic experience for a autonomous, self-control, fulfilling and unforgettable experience. The dimensions that transformed the labor context were linked to the experience of women and were related to world of life category. The analysis showed that they were more promising than category system, in other words , institutions, spaces, organization systems and guidelines governed by power or money. The processing dimensions were represented by groups who take the initiative to provide the dissemination of knowledge to women or who brought innovations (epi-no equipment, for example). In the case of cause difficulties dimensions, it was observed that the elements that related to the system and those related to the world of life is presented in similar numbers, showing that the woman is motivated to prepare the natural birth is difficult, both in his personal / family life, as in institutions. This work demonstrated that the changes initiated in the world of life category and that women rethought their way to see the birth, overcame their fears and naturelly tried to "convince" people around them. In the population studied was noted that the epi-no reduced lacerations, episiotomies warned, however in some cases did not prevent lacerations 1st degree. It is hoped that this work contribute to reflections on the delivery care model in order to rescue the female autonomy in childbirth and reduce myths and anxiety around the issue, reaffirming the importance, both from a personal point of view as a social and epidemiological , to follow the recommendations of the World Health Organization, as regards the issue of labor and birth. / O presente trabalho intitula-se A busca pelo parto natural e motivações para o preparo do assoalho pélvico com o epi-no e teve como principais objetivos: compreender os elementos envolvidos na escolha da mulher pelo parto natural, identificar motivações para o preparo do assoalho pélvico com o epi-no, visando o parto natural e identificar as dimensões que facilitam e aquelas que dificultam essa escolha. Foi realizado com gestantes que faziam parte do Programa de Epi-no, iniciativa do Laboratório de Saúde da Mulher de uma Universidade do interior de São Paulo, entre os anos 2013 e 2014. Trata-se de uma pesquisa qualitativa, para a qual se utilizou como referencial teórico-metodológico, o Feminismo Dialógico proposto por Lygia Puigvert (2001) e a Metodologia Comunicativa Crítica (MCC) proposta por Gomez et al (2006), ambos ancorados nos referenciais teóricos da Aprendizagem Dialógica, que por sua vez se baseiam no conceito da Ação Comunicativa de Habermas (1999) e na Dialogicidade de Paulo Freire (1994; 2005). A MCC busca identificar as dimensões facilitadoras, ou seja, aquelas que promovem, neste caso, uma vivência prazerosa do parto e as dimensões dificultadoras, ou seja, aquelas que representam uma barreira à esta vivência, relacionando ambas às categorias mundo da vida e sistema. A coleta de dados foi iniciada em novembro/ 2013 e a análise foi organizada conforme o nível básico de análise proposto pela MCC. Foram entrevistadas oito mulheres, sete delas concluíram as duas fases do relato comunicativo, de acordo com a metodologia e houve cancelamento de uma entrevista, devido à perda de material. As mulheres tinham entre 22 e 38 anos com predominância de idade acima dos 30 anos, todas tinham companheiro, cinco eram primíparas (1ª gestação) e duas multíparas (2 ou mais gestações), com histórico de cesárea e abortos e todas realizaram o parto no ambiente hospitalar. Os resultados mostraram que a descoberta da gravidez incitou, nessas mulheres, curiosidade em dialogar com familiares, amigos e profissionais da saúde sobre o parto natural; despertou a busca pessoal por informações (livros, revistas, internet, grupos de apoio ao parto natural); motivou para o preparo do assoalho pélvico com o epi-no, entre outros. O parto, visto anteriormente como traumático e cercado de intervenções (ocitocina, episiotomia, Kristeller) e sofrimento, em geral ganhou um novo significado e passou de uma experiência traumatizante para uma experiência autônoma, de autocontrole, realizadora e inesquecível. As dimensões que facilitam o contexto do parto estavam ligadas à vivência das mulheres e se relacionaram a categoria mundo da vida. A análise mostrou que foram mais promissoras do que aquelas que se apresentaram a categoria sistema, ou seja, as instituições, espaços, sistemas de organização e diretrizes reguladas pelo poder ou dinheiro. As dimensões facilitadoras foram representadas por grupos que tomam a iniciativa de proporcionar a difusão de conhecimento para as mulheres ou que trouxeram inovações (equipamento epi-no, por exemplo). No caso das dimensões dificultadoras, observou-se que, os elementos que se relacionaram ao sistema e os que se relacionaram ao mundo da vida se apresentaram em números equiparados, demonstrando que a mulher que se motiva para o preparo do parto natural encontra dificuldades, tanto em sua vida pessoal/familiar, quanto nas instituições. Este trabalho demonstrou que as mudanças iniciaram no mundo da vida e que as mulheres repensaram sua forma de ver o parto, superaram seus medos e tentaram contagiar as pessoas em seu entorno. Na população estudada notou-se que o epi-no reduziu as lacerações, preveniu episiotomias, porém em alguns casos não evitou lacerações de 1º grau. Espera-se com este trabalho contribuir para reflexões acerca do modelo de atenção ao parto, de forma a resgatar a autonomia feminina no parto e reduzir mitos e ansiedade em torno do tema, reafirmando a importância, tanto do ponto de vista pessoal como social e epidemiológico, de atender as recomendações da Organização Mundial da Saúde, no que se refere às questões do parto e nascimento.

Polycyclic polyprenylated acylphloroglucinols (PPAPs) are plant- (Guttiferae) derived natural products. They have fascinating bicyclo[3.3.1]nonane-2,4,9-trione or [3.2.1]nonane-2,4,8-trione cores decorated with prenyl or geranyl groups. More than 200 PPAPs have been isolated, but only a few of them have been synthesized, although most of the synthesized PPAPs are of type A and have an exo substituent at C (7). Here, we are trying to make a type B 7-endo PPAP, 7-epi-clusianone. The synthetic plan involves an alkynylation–aldol strategy to construct the bicyclic core. Having established the bicyclic core, the synthesis presents a new challenge: the oxidation of a very hindered 2-alkenone to the β-hydroxy 2-alkenone.

Inhibition of cyclooxygenase (COX)-2 increases cardiovascular deaths. Identifying a biomarker of COX-2 is desirable but difficult, since COX-1 and COX-2 ordinarily catalyze formation of an identical product, prostaglandin H2. When acetylated by aspirin, however, COX-2 (but not COX-1) can form 15(R)-HETE, which is metabolized to aspirin-triggered lipoxin (ATL), 15-epi-lipoxin A4. Here we have used COX-1- and COX-2-knockout mice to establish whether plasma ATL could be used as a biomarker of vascular COX-2 in vivo. Vascular COX-2 was low but increased by LPS (10 mg/kg; i.p). Aspirin (10 mg/kg; i.v.) inhibited COX-1, measured as blood thromboxane and COX-2, measured as lung PGE2. Aspirin also increased the levels of ATL in the lungs of LPS-treated wild-type C57Bl6 mice (vehicle: 25.5±9.3 ng/ml; 100 mg/kg: 112.0±7.4 ng/ml; P<0.05). Despite this, ATL was unchanged in plasma after LPS and aspirin. This was true in wild-type as well as COX-1−/− and COX-2−/− mice. Thus, in mice in which COX-2 has been induced by LPS treatment, aspirin triggers detectable 15-epi-lipoxin A4 in lung tissue, but not in plasma. This important study is the first to demonstrate that while ATL can be measured in tissue, plasma ATL is not a biomarker of vascular COX-2 expression.—Kirkby, N. S., Chan, M. V., Lundberg, M. H., Massey, K. A., Edmands, W. M. B., MacKenzie, L. S., Holmes, E., Nicolaou, A., Warner, T. D., Mitchell, J. A. Aspirin-triggered 15-epi-lipoxin A4 predicts cyclooxygenase-2 in the lungs of LPS-treated mice but not in the circulation: implications for a clinical test.

The study sought to determine the meaning and interpretation by facility managers and nurses on utilisation of expanded programme on immunisation and integrated management of childhood illnesses (EPI and IMCI) programmes for follow-up and antibody testing of HIV-exposed infants (HEI) at 18 months. Also to understand the factors within the health systems that influence the follow-up and antibody testing. The study setting selected was six facilities in Steve Tshwete subdistrict in Nkangala district of Mpumalanga province in South Africa. The study used a hermeneutic phenomenology using in-depth interviews for collecting data from 4 facility managers and 12 nurses. The major themes that emerged from the interviews were referral, defaulting, integration, stigma, and off-site ART initiation within the health system. These were found to influence the utilisation of HEI and IMCI services for follow-up and management of HEI. It was also found that the importance of integrating the management of HEI into the EPI and IMCI cannot be overemphasised. It was concluded that the Health Department needs to be vigilant and use all available resources to manage HEI to meet the MDG 4 of prevention of infant mortality / Health Studies / M.A. (Nursing Science)

Este trabalho teve como principal propósito discutir a segurança e a saúde no trabalho rural com agrotóxicos, especialmente no Brasil. De modo geral, essa discussão tem se limitado à proposição de medidas individuais de controle de riscos. Segundo conceitos de segurança e higiene do trabalho estas deveriam ser propostas como complementação às medidas coletivas de controle de riscos, consideradas prioritárias. No entanto, as medidas coletivas não têm sido abordadas como objeto principal dessa discussão. Assim, o trabalho buscou analisar as limitações práticas e conceituais do enfoque predominante e mostrar a necessidade de ampliar a discussão através da proposição de medidas coletivas para enfrentar a complexa questão que envolve as condições de trabalho com agrotóxicos. O trabalho baseia-se, principalmente, em revisão bibliográfica. Na primeira parte do trabalho faz-se uma exposição buscando mostrar a dimensão da utilização dos agrotóxicos e as principais culturas em que são empregados. Apresentam-se indicativos do potencial de exposição da população que trabalha com esses produtos. Procede-se, ainda, a uma descrição sobre os principais impactos provocados pelos agrotóxicos na agricultura, no meio ambiente e na saúde humana. A segunda parte dedica-se à discussão das medidas para o controle dos riscos no trabalho com agrotóxicos. Primeiramente se procede a uma análise do enfoque que responsabiliza basicamente ao usuário pelos problemas decorrentes do uso dos agrotóxicos. Exemplifica-se a sua predominância entre os diversos segmentos envolvidos com a questão, discutem-se os possíveis motivos que levam à essa predominância e analisam-se as limitações conceituais desse enfoque. Em seguida são discutidas as medidas individuais de controle de riscos, evidenciando-se principalmente as dificuldades de ordem prática para sua implantação nas condições do trabalho rural. A importância, os problemas, e as necessidades relacionadas aos equipamentos de proteção individual nas atividades de trabalho com agrotóxicos são detalhadamente analisados. Também se discute a eficácia das medidas de controle de riscos baseadas exclusivamente no comportamento do trabalhador. A seguir, faz-se uma abordagem das medidas coletivas cabíveis para o controle de riscos no trabalho rural com agrotóxicos. Dois campos de ação são examinados como medidas de engenharia para o controle de riscos: os sistemas de aplicação dos agrotóxicos e o processo de produção agrícola. Discutem-se as condições de segurança dos equipamentos de aplicação mais comumente empregados em nosso meio e sugere-se a obrigatoriedade de colocar no mercado apenas os equipamentos considerados mais seguros. Na discussão sobre o controle de riscos no processo produtivo agrícola, analisam-se as práticas produtivas que propiciam a instalação de pragas e doenças nas lavouras e as vantagens do Manejo Integrado de Pragas - MIP - enquanto sistema que minimiza a necessidade de agrotóxicos. Depois analisam-se as condições necessárias para sua difusão, especialmente entre os pequenos produtores rurais. Propõe-se, ainda, a inclusão da segurança do trabalhador rural como um dos parâmetros de decisão para a definição das medidas de controle de pragas no MIP. Além das medidas de engenharia, face às carências estruturais de ordem técnica, social e econômica existentes no país, propõe-se como medida essencial o controle da disponibilidade dos agrotoxicos, especialmente dos mais tóxicos, através de mecanismos legais e econômicos. Evidencia-se a necessidade de proceder a análises de impacto econômico e de risco/benefício nos casos de restrições e banimentos, assim como também para o registro de agrotóxicos. O estabelecimento de políticas de taxação e de regulamentação de preços, visando desviar a preferência dos agricultores pelos produtos mais perigosos para os de menor risco, também é considerado. Propõe-se. ainda, que se estude as estratégias adotadas em programas de redução geral no uso de agrotóxicos que estão sendo realizados em diversos países, segundo as condições existentes no Brasil, pois os resultados que vêm sendo obtidos não comprometem a produção agrícola e têm trazido benefícios para o meio ambiente e para a saúde pública. Por fim, recomenda-se que o Poder Público estabeleça estratégias e garanta a necessária estrutura de suporte para a definição de uma política conseqüente de segurança e saúde no trabalho com agrotóxicos / This dissertation had the main purpose of\' discussing safety and health concerning the use of pesticides in agriculture, in Brazil. This discussion has usually been limited to the proposal of individual risk control precautions which, according to occupational safety and hygiene concepts, should be proposed as complements of collective control precautions. Although collective control is assigned as priority, it has not been at the central focus of this discussion as it should be. Thus, the dissertation aimed to examine conceptual and practical limitations of the prevailing focus and to highlight the need of a broad reflection in order to point out collective proposals to face the complex problem of working with these chemicals. Bibliographical references were examined and considered in this analysis. The first part presents data of pesticide use and of potential exposure of rural workers in Brazil. It also describes the main impacts pesticides cause in agriculture, in the environment and in human health. The second part discusses risk control in pesticide usage. First it is analyzed the prevailing approach that points the worker as the responsible of pesticide related problems. Examples are provided to show how this predominance took place and to present the conceptual limitations associated with it. Arguments about the importance of collective pesticide risk control are added. The main practical difficulties concerning the implementation of personal protective equipments in rural work conditions are presented. The importance, the problems and the needs related to personal protection in the pesticide working activities are examined in detail; as well as the effectiveness of occupational hazard controlling methods based exclusively in the workers\' behavior. Then, collective control measures aimed to rural work with pesticides are discussed. Two levels of action are examined as risk control engineering: pesticide application methods and the agricultural production system. Safety conditions of the most commonly used pesticide application devices are discussed, and it is suggested that only the equipments considered safer should be available in the market. The discussion of the agricultural production process as a risk control procedure itself follows, and production practices that favors the incidence of pest attacks arc compared to the advantages of the Integrated Pest Management as a system that reduces the need of pesticide use to a minimum, the conditions required to the Integrated Pest Management to become widespread, specially to small farms, are considered. It is also suggested that rural worker safety should be taken into account as one of the parameters to decision-making in Integrated Pest Management. Besides engineering measures, legal and economical constraints are proposed as important means to accomplish effective control of pesticides availability, specially of the most toxic chemicals, to cope with the structural technical, social and economical deficiencies faced by the country. The need of undergoing cost/benefit and economical impact analysis studies for the cases of banishment or severe use restriction of specific chemicals are stressed. The same studies should be applied to product registration procedures. Tax and price policies should also be established in order to dissuade farmers of using highly toxic pesticides, therefore stimulating preference for less dangerous products. It is also proposed that general pesticide usage reduction strategies ongoing in other countries should be studied accordingly to Brazilian conditions. These experiences has shown the possibility of reductions in pesticide usage with little or without losses in agricultural production along with real benefits to the environment and public health. Finally, the establishment of strategies and regulations enforcement by public authorities are recommended as necessary actions to compose a policy that aims to safety and health in the work with pesticides

Este trabalho teve como principal propósito discutir a segurança e a saúde no trabalho rural com agrotóxicos, especialmente no Brasil. De modo geral, essa discussão tem se limitado à proposição de medidas individuais de controle de riscos. Segundo conceitos de segurança e higiene do trabalho estas deveriam ser propostas como complementação às medidas coletivas de controle de riscos, consideradas prioritárias. No entanto, as medidas coletivas não têm sido abordadas como objeto principal dessa discussão. Assim, o trabalho buscou analisar as limitações práticas e conceituais do enfoque predominante e mostrar a necessidade de ampliar a discussão através da proposição de medidas coletivas para enfrentar a complexa questão que envolve as condições de trabalho com agrotóxicos. O trabalho baseia-se, principalmente, em revisão bibliográfica. Na primeira parte do trabalho faz-se uma exposição buscando mostrar a dimensão da utilização dos agrotóxicos e as principais culturas em que são empregados. Apresentam-se indicativos do potencial de exposição da população que trabalha com esses produtos. Procede-se, ainda, a uma descrição sobre os principais impactos provocados pelos agrotóxicos na agricultura, no meio ambiente e na saúde humana. A segunda parte dedica-se à discussão das medidas para o controle dos riscos no trabalho com agrotóxicos. Primeiramente se procede a uma análise do enfoque que responsabiliza basicamente ao usuário pelos problemas decorrentes do uso dos agrotóxicos. Exemplifica-se a sua predominância entre os diversos segmentos envolvidos com a questão, discutem-se os possíveis motivos que levam à essa predominância e analisam-se as limitações conceituais desse enfoque. Em seguida são discutidas as medidas individuais de controle de riscos, evidenciando-se principalmente as dificuldades de ordem prática para sua implantação nas condições do trabalho rural. A importância, os problemas, e as necessidades relacionadas aos equipamentos de proteção individual nas atividades de trabalho com agrotóxicos são detalhadamente analisados. Também se discute a eficácia das medidas de controle de riscos baseadas exclusivamente no comportamento do trabalhador. A seguir, faz-se uma abordagem das medidas coletivas cabíveis para o controle de riscos no trabalho rural com agrotóxicos. Dois campos de ação são examinados como medidas de engenharia para o controle de riscos: os sistemas de aplicação dos agrotóxicos e o processo de produção agrícola. Discutem-se as condições de segurança dos equipamentos de aplicação mais comumente empregados em nosso meio e sugere-se a obrigatoriedade de colocar no mercado apenas os equipamentos considerados mais seguros. Na discussão sobre o controle de riscos no processo produtivo agrícola, analisam-se as práticas produtivas que propiciam a instalação de pragas e doenças nas lavouras e as vantagens do Manejo Integrado de Pragas - MIP - enquanto sistema que minimiza a necessidade de agrotóxicos. Depois analisam-se as condições necessárias para sua difusão, especialmente entre os pequenos produtores rurais. Propõe-se, ainda, a inclusão da segurança do trabalhador rural como um dos parâmetros de decisão para a definição das medidas de controle de pragas no MIP. Além das medidas de engenharia, face às carências estruturais de ordem técnica, social e econômica existentes no país, propõe-se como medida essencial o controle da disponibilidade dos agrotoxicos, especialmente dos mais tóxicos, através de mecanismos legais e econômicos. Evidencia-se a necessidade de proceder a análises de impacto econômico e de risco/benefício nos casos de restrições e banimentos, assim como também para o registro de agrotóxicos. O estabelecimento de políticas de taxação e de regulamentação de preços, visando desviar a preferência dos agricultores pelos produtos mais perigosos para os de menor risco, também é considerado. Propõe-se. ainda, que se estude as estratégias adotadas em programas de redução geral no uso de agrotóxicos que estão sendo realizados em diversos países, segundo as condições existentes no Brasil, pois os resultados que vêm sendo obtidos não comprometem a produção agrícola e têm trazido benefícios para o meio ambiente e para a saúde pública. Por fim, recomenda-se que o Poder Público estabeleça estratégias e garanta a necessária estrutura de suporte para a definição de uma política conseqüente de segurança e saúde no trabalho com agrotóxicos / This dissertation had the main purpose of\' discussing safety and health concerning the use of pesticides in agriculture, in Brazil. This discussion has usually been limited to the proposal of individual risk control precautions which, according to occupational safety and hygiene concepts, should be proposed as complements of collective control precautions. Although collective control is assigned as priority, it has not been at the central focus of this discussion as it should be. Thus, the dissertation aimed to examine conceptual and practical limitations of the prevailing focus and to highlight the need of a broad reflection in order to point out collective proposals to face the complex problem of working with these chemicals. Bibliographical references were examined and considered in this analysis. The first part presents data of pesticide use and of potential exposure of rural workers in Brazil. It also describes the main impacts pesticides cause in agriculture, in the environment and in human health. The second part discusses risk control in pesticide usage. First it is analyzed the prevailing approach that points the worker as the responsible of pesticide related problems. Examples are provided to show how this predominance took place and to present the conceptual limitations associated with it. Arguments about the importance of collective pesticide risk control are added. The main practical difficulties concerning the implementation of personal protective equipments in rural work conditions are presented. The importance, the problems and the needs related to personal protection in the pesticide working activities are examined in detail; as well as the effectiveness of occupational hazard controlling methods based exclusively in the workers\' behavior. Then, collective control measures aimed to rural work with pesticides are discussed. Two levels of action are examined as risk control engineering: pesticide application methods and the agricultural production system. Safety conditions of the most commonly used pesticide application devices are discussed, and it is suggested that only the equipments considered safer should be available in the market. The discussion of the agricultural production process as a risk control procedure itself follows, and production practices that favors the incidence of pest attacks arc compared to the advantages of the Integrated Pest Management as a system that reduces the need of pesticide use to a minimum, the conditions required to the Integrated Pest Management to become widespread, specially to small farms, are considered. It is also suggested that rural worker safety should be taken into account as one of the parameters to decision-making in Integrated Pest Management. Besides engineering measures, legal and economical constraints are proposed as important means to accomplish effective control of pesticides availability, specially of the most toxic chemicals, to cope with the structural technical, social and economical deficiencies faced by the country. The need of undergoing cost/benefit and economical impact analysis studies for the cases of banishment or severe use restriction of specific chemicals are stressed. The same studies should be applied to product registration procedures. Tax and price policies should also be established in order to dissuade farmers of using highly toxic pesticides, therefore stimulating preference for less dangerous products. It is also proposed that general pesticide usage reduction strategies ongoing in other countries should be studied accordingly to Brazilian conditions. These experiences has shown the possibility of reductions in pesticide usage with little or without losses in agricultural production along with real benefits to the environment and public health. Finally, the establishment of strategies and regulations enforcement by public authorities are recommended as necessary actions to compose a policy that aims to safety and health in the work with pesticides

Natural product synthesis is one of the most creative branch of chemistry in terms of its boundless scope for innovation and has stimulated several generations of synthetic organic chemists. With advancement in the technology, particularly in the isolation and purification techniques, high-field NMR and X-ray crystallography, it has become fairly routine to isolate and assign the structures, high-field NMR and X-ray crystallography, it has become fairly routine to isolate and assign the structures, even to those complex molecules, which are available only in microscopic quantities from natural sources. Concurrently, one has witnessed tremendous advances in the availability of new synthetic methodologies with high region-, stereo-, and enantiocontrol for one or multiple C-C bond formations and rapid generation of molecular complexity. These developments have rekindled interest with total synthesis of natural products as platforms for testing and validating new reactions and strategies. Many natural products exhibit wide range of biological activities and thus provide good leads in drug discovery but quite often such bioactive compounds are obtained only in minute quantities from Nature. Hence, there is need to synthesize them to obtain requisite quantities and build diversity around their scaffold to further explore their therapeutic potential. Thus, natural product synthesis combines both intellectual challenge and possible application for human wellbeing. Our research group is actively engaged in the synthesis of structurally complex, bioactive natural products and as a part of this endeavour, total syntheses of several bioactive compounds have been accomplished in our laboratory in recent past. The present thesis has also evolved around the ongoing theme directed towards natural product synthesis and is organized under three chapters. Chapter I: Total synthesis of (+)-1S-Minwanenone Chapter II: Enantioselective total synthesis of the bioactive natural product (+)-Sch 642305. Chapter III: Enantiospecific total synthesis of 6-epi-(-)-Hamigeran B.

The construction of diverse molecular architecture conceived and created by Nature, continues to be the most exiting and challenging task to the practitioners of organic synthesis. As a result of refinement in isolation and purification techniques, recent advances in the spectroscopic methods particularly two-dimensional NMR spectroscopy and routine use of single crystal X-ray crystallography, the isolation and structural elucidation of the complex natural products has become a routine exercise. Even those natural products which are present in minute quantity, are being unraveled from the newer and exotic sources such as marine flora and fauna, microbial organisms and insect world. This has been a big boon for the synthetic organic chemists, providing them with increasing number of exciting objectives. The recent advances in the field of natural product synthesis testify to the organic chemists endeavors to meet these emerging challenges. Nature's expertise and virtuosity in creating a phenomenal array of carbocyclic frameworks is most notably highlighted in the terpenoid group of natural products. Indeed, the number and type of carbocyclic skeleta among terpenes continues to grow unabated as more and more natural products are being routinely isolated from the various sources. Thus, various polycyclic natural products bearing new and novel fused assemblies of five, six, seven and eight membered rings and replete with dense functionalization and stereogenic centers are being regularly encountered. The present investigation represents synthetic efforts towards some novel and recently isolated terpenoid natural products. Two main themes have been pursued. The first involves the construction of a functionalized hydroazulene framework employing RCM as the key step and its further elaboration to the 5,7,6-tricyclic framework present in diterpene guanacastepene-A and 5,11-fused bicyclic system present in neodolabellane diterpenes. The second theme explores the synthetic versatility of the well-established photo-thermal metathetic approach to linear triquinanes through its application to the total synthesis of novel and recently isolated natural product cucumin E. It further explores the utility of 5-5-5 fused ring system to access 5-8 system. This strategy has led to the stereoselective total synthesis of natural product asterisca-3(15),6~diene belonging to the rare asteriscane family. The present thesis entitled "Towards the Total Synthesis of Terpenoid Natural Products" describes our endeavors towards the synthesis of 5-7-6, 5-11, 5-5-5 and 5-8 fused natural products and has been organized under four chapters. Chapter I. Studies toward the total synthesis of novel diterpene antibiotic guanacastepene A. Chapter EL Synthesis of the novel 5,11-fused bicyclic framework of neodollabellane diterpenoids. Chapter HI. A Stereoselective total synthesis of the novel triquinane sesquiterpene cucumin E. Chapter IV. Total synthesis of 5-8 ring fused sesquiterpene hydrocarbon asterisca-3(15),6-diene. The Chapter I describes a stereoselective approach towards the construction of the novel 5,7,6-rig fused framework present in the diterpene antibiotic guanacastepene A 1, recently isolated from an unidentified fungus growing on the tree Daphnopsis americana by Clardy et al. Besides its structural novelty, guanacastepene A exhibits impressive activity towards methicilline-resistant Staphylococcus aureus and vancomycine-resistant Entereococcusfaecium. Thus, 1 has evoked an unprecedented attention from the synthetic community and we too were enticed to enter this arena. Scheme 1 (structural formula) The synthetic approach towards guanacastepene A 1, envisage in this study, was revealed through a retrosynthetic analysis which identified hydroazulenic core 2 (AB rings) with requisite level of functionalities as an advanced precursor to which a six membered ring could be annulated through appropriate protocols. The hydroazulene core 2 was to be accessed from the substituted cyclopentenone 4 through the intermediacy of 3 and the former in turn could be prepared from the readily available endo tricyclo[5.2.1.026]deca-3,8-diene-5-one 6, Scheme 1. In this approach to the AB ring hydroazulenic core 2 of 1, some essential requirements were recognized at the outset. These were the setting up the key cis relationship of the angular methyl group at C11 and the neighboring bulky-isopropyl group at C12, installation of a desirable level of functionalization in the five membered ring and a functional group handle in seven-membered ring to Scheme 2 (structural formula) append the six membered ring with requisite functionality. Keeping these considerations in mind, readily available endo-tricyclo[5.2.1.02-6]deca-3,8-diene-5-one 6 with well-established propensity toward reactivity on exro-face was identified to be starting point, Scheme 1. Copper(I)mediated stereoselective 1,4-addition of isopropylmagnesium iodide on 6, followed by sequential a-alkylation with allyl bromide and methyl iodide led to 7 as a single diastereomer and correctly installed the methyl and isopropyl groups in the required cis-relationship, Scheme 2* Retro-Diels-^Ider reaction in 7 under flash vacuum pyrolysis (FVP) liberated the cyclopentenone 8. For the annulation of a seven-membered ring to cyclopentenone 8, recourse was taken to a ring closing metathesis-(RCM) based protocol. Barbier-type addition of 4-bromo-1-butene to 8 in the presence of lithium metal and oxidative transposition of the resulting allylic alcohol with PCC furnished enone 9 in good yield. On exposure to Grubbs' catalyst, enone 9 underwent smooth RCM reaction to deliver the desired hydroazulenic framework 10, Scheme 2. The bicyclic hydroazulenic enone 10 was now poised for the elaboration of functionalities in the context of evolution to the natural product 1. Thus, 10 was elaborated to epoxy alcohol 11 in a three step sequence, Scheme 2. TMSOTf mediated opening of epoxide ring to yield cis-enediol, protection of the resultant diol as an acetonide and allylic oxidation furnished the key enone 12, Scheme 2. Attempts to alkylate the enone 12 to install the C16 methyl group and the precursor side chain for six membered ring annulation failed consistently. Recourse was then taken to a-carboethoxylation in 12 using Mander's reagent proved to be quite effective and further alkylation with methyl iodide furnished 13 as a single stereoisomer with the correct stereochemical positioning of the quaternary methyl group at C8. Intermediate 13 was elaborated to tricyclic framework 14 of guanacastepane A in five steps, by setting up NaOEt mediated intramolecular aldol reaction as key step, for the construction of six membered ring, Scheme 2. In tricyclic cross-conjugated dienone 14, complete carbon framework of the natural product guanacastepene A 1, with a copious disposition of functionalities was realized. Further efforts to transform 14 to 1 were not very encouraging. However a variant of ring C annulation on 12 is being investigated by a colleague in the group to achieve the total synthesis of the natural product. In travails towards 1 and 14, several deviations from the expected course, leading to the new tricyclic structural variants of the biologically promising guanacastepene A 1 were encountered and these findings will also be detailed in this chapter of the thesis. In the Chapter n of the thesis, synthetic studies directed towards the bicyclic framework present in novel neodolabellane type diterpenes like a-and (3-neodolabellenol 17a and 17b isolated from an unknown species of Australian soft coral by Coll et al will be delineated. The readily accessible bicyclic hydroazulenic enone 13, also served as an advanced intermediate for the construction of the 5-11 fused bicyclic skeleton 16 of neodollabellane diterpenoids via an oxy-Cope rearrangement. Elaboration of 13 to the divinyl carbinol 15 and its [3.3] sigmatropic rearrangement (oxy-Cope rearrangement) to 16 and related reactions will be described, Scheme 3. Scheme 3(Structral formula) Chapter III describes the first total synthesis of the sesquiterpenoid natural product cucumin E 26 bearing a novel triquinane framework, and reported recently from the mycelial cultures of agaric Macrocystidia cucumis (Pers ex Fr.) by the groups of Steglich and Anke. Synthesis of 26 was accomplished following an interesting variant of the photo-thermal metathetic approach to linear triquinanes delineated by us sometime ago, Scheme 4. Cucumin E 26 attracted our attention as this sesquiterpene [Scheme 4 (Structural formula)] bears an Interesting biogenetic relationship to the related hirsutane group of linear triquinanes from which it can be derived through the migration of a methyl group. Towards the synthesis of 26, the readily available pentacyclic dione 18 was identified as the key starting material and was elaborated to 19 using FVP (flash vacuum pyrolysis) conditions under which 18 underwent [2+2]-cycloreversion of the cyclobutane ring to furnish the cis, syn, cis-triquinane, Scheme 5. On exposure to base, 19 could be equilibrated through back and forth double bond isomerization to furnish the cis,antecis-isorner 20 in reasonable yield. Attention was now turned towards the installation of the network of four methyl groups present in 26 and relevant functional group adjustments. Catalytic hydrogenation of 20, selective mono-Wittig olefination and subsequent gem-dimethylation furnished olefinic ketone 21. At this stage, the carbonyl group in 21 was sought to be removed and recourse was taken to the Barton deoxygenation protocol to furnish 22, Scheme 5. The next task en-route to the cucumin skeleton was the introduction of the angular methyl group at C7 to generate the complete Cis carbon framework. For this purpose, the ketal group in 22 was deprotected to furnish the ketone 23. Angular methylation in 23 exhibited fair regioselectivity to yield 24 as the major product. The enone moiety in 24 was established through allylic oxidation following the Sharpless catalytic selenium dioxide oxidation followed by PDC oxidation to afford 25. Rh(III)-mediated isomerization of the exocyclic double bond in 25 delivered cucumin E 26, whose spectral characteristics were exactly identical to the natural product as established through direct comparison, Scheme 5. In Chapter IV, the total synthesis of the bicyclo[6.3.0]undecane-based sesquiterpene hydrocarbon asterisca-3(15),6-diene 38, isolated from Lippia integrifolia (Griseb) by Konig et al. and representing the simplest member of the asteriscane family, is described. Our approach to the bicyclo[6.3.0]undecane system was based on the 'carbocyclic ring equivalency' concept. Thus, bicyclo[3.3.0]octane ring system is an eight-membered ring equivalent and tricyclo[6.3.0.02'6]undecane (linear triquinane system) is the latent form of the bicyclo[6.3-0]undecane system through the scission of the central bond as shown in Scheme 6. Following this concept a synthesis of 38 was envisaged from the cfe,syn, cis-triquinane bis-enone 28, readily and quantitatively available from the pentacyclic-caged dione 27, through flash-vacuum pyrolysis (FVP), as described earlier. More stable bis-enone 29 was obtained from 28 by relocation of one of the enone moieties in 28 through thermal activation under static conditions. The two double bonds in 29 could be now easily differentiated and hence it served as an appropriate substrate for further elaboration. Thus, bis-enone 29 on selective catalytic hydrogenation and regioselective gem-dimethylation afforded 30, Scheme 7. At this stage, the two-carbonyl functionalities in 30 were sought to be removed and this was achieved in a stepwise manner. The sequence involved chemoselective thioketalisation of the enone carbonyl followed by reductive desulfurization in metal-ammonia milieu and led to a diastereomeric mixture of alcohols (resulting from the concurrent reduction of the saturated ketone under metal-ammonia conditions). The diastereomeric mixture of alcohols was deoxygenated following the Barton protocol to yield tricyclic hydrocarbon 31, Scheme 7. Catalytic ruthenium mediated oxidative fragmentation of the tetrasubstituted olefinic bond in 31 afforded the 5,8-fused os-bicyclic dione 32. Wittig olefination of cis-bicyclic dione 32 proceeded regioselectively at the carbonyl group distant from the ring junction and furnished keto-olefin 33. However, the isomerization of exocyclic double bond in 33 to the desired endo position (corresponding to C6-C7 in the natural product) to yield 34 proved to be difficult due to unwanted transannular cyclization. Consequently, the transformation of 33 to the desired 34 was carried out through a five-step sequence. The sequence involved the reduction of the carbonyl group in 33 to yield alcohol, protection of the resultant alcohol as IMS-ether and RhCb mediated isomerization of the exo-double bond to the desired endo position. Further deprotection of the TMS ether and oxidation led to the acquisition of the expected enone 34, Scheme 7. Finally, the exo- methylene unit present in the natural product was installed by Wittig olefination in 34 to furnish 35, corresponding to the 'assigned structure' of the natural product. However the spectral data of synthetic 35 was distinctly different from that reported for the natural product and a revision of the natural product structure was warranted. A careful analysis of the spectral data led us to the surmise that the natural product could be the trans-isomer and we embarked on its synthesis. Consequently, cis-bicyclic diketone 32 on exposure to base could be readily equilibrated to the more stable trans-isomer 36 in which the later was the major product (1:4). Bicyclic trans-dione 36, like its cis sibling 32 underwent a facile regioselective Wittig olefination to yield keto-olefin 37, Scheme 8. RhCk-mediated double-bond isomerization in 37 proceeded without any complications and gave a readily separable mixture of regiomeric olefinic ketones 38 and 39 in the ratio 2:3, respectively. Wittig olefination on the required keto olefin 39 proceeded smoothly to furnish the bicyclic hydrocarbon 40 whose spectral characteristics [lH NMR, 13C NMR) exactly matched those reported for the natural product, Scheme 8. A total synthesis of the natural product asterisca-3(15),6-diene has been accomplished. These synthetic efforts necessitate the revision of the earlier assigned structure of the natural product from cis-35 to trans-38. (For structural formula pl see the original document)