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Warfarin metabolism and disposition in anticoagulant-resistant and susceptible mouse strainsSutcliffe, Frances Anne January 1986 (has links)
The differential susceptibilities of warfarin-susceptible LAC-grey and warfarin-resistant HC house mice to the anticoagulant effect of the oral rodenticide 3-(alpha-acetonyl benzyl)-4-hydroxycoumarin (Warfarin) in terms of their blood clotting times, were determined. The hypoprothrombinaemic effect of both the R(+) and S(-) warfarin enantiomers was also investigated, in addition to the standard test for warfarin-resistance in mice, the ability to survive on a diet containing 0.025% warfarin for 21 days. Onto this base of knowledge of the exact hypoprothrombinaemic responses evoked by treatment of both warfarin- susceptible and warfarin-resistant mice with warfarin at various doses, a structured analysis of the biochemical consequence(s) of expression of the major warfarin-resistance gene, War, could be built. Thus, changes in the in vivo pharmacokinetic parameters including half-life (t[1/2]), plasma clearance (Cl[p]), apparent volume of distribution (Vd[app]) and bioavailability (F) were documented for both R(+) and S(-) warfarin in both males and females of the two mouse strains. Similarly, in vitro hepatic microsomal metabolite profiles following pretreatment with warfarin, phenobarbitone, beta-naphthoflavone and clofibrate, excretion of unchanged warfarin enantiomers and warfarin metabolites and finally plasma protein binding parameters were determined in LAC-grey and HC mice. Therefore, it was possible to correlate changes in the pharmacokinetics, metabolism and disposition of warfarin in these mice with their differential anticoagulant sensitivities. Accordingly, the biochemical mechanism(s) of the expression of the major warfarin-resistance gene, War, has (have) been proposed to be due, at least in part, to a combination of a greater plasma clearance of the more potent S(-) warfarin enantiomer in females, a larger hepatic uptake of the same enantiomer in both sexes, and a greater degree of plasma protein binding of both enantiomers of warfarin.
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Agronomic and physiological responses of resistant and susceptible cotton genotypes to reniform nematode severity and soil nitrogenSingh, Bhupinder 01 May 2020 (has links)
Rotylenchulus reniformis (RN) nematode infection has been identified as a major biotic factor limiting cotton yield (~8%) in Mississippi. Cotton researchers are striving to develop resistance to RN and develop management practices to mitigate the problem. Reniform nematode and soil nitrogen (N) directly affect cotton growth and physiology, however, responses to RN and N may vary across a wide genetic background. The overall objective of this research was to determine the role that host plant resistance to reniform nematode and soil nitrogen plays in cotton growth, physiology, and yield and controlling RN populations. In experiment 1, the effect of RN on resistant (Gossypium barbadense introgressions; 08SS110-NE06.OP and 08SS100) along with a susceptible genetic standard (Deltapine 16) and a commercially, susceptible cultivar (PHY 490 W3FE) was studied based on growth, development, and yield characteristics under field conditions. In experiment 2, the effect of N application rates, ranging from 0-150%, with 100% being recommended rate, on early season morphological and physiological traits of the resistant and susceptible genotypes were studied in the presence and absence of RN under greenhouse conditions. In the field project, agronomic traits varied among genotypes at a given sampling time but growth rates, described by three-parameter sigmoidal function (r2 = 0.95 to 0.99), were not different among genotypes. Further, genotypes exhibited higher agronomic and physiological traits, including plant height, main stem nodes, leaf area, net photosynthetic rates, and hand-picked lint yields in 2018 than 2017. In the greenhouse study, 08SS110-NE06.OP performed physiologically better across RN environments than other genotypes, but growth rates with respect to soil N treatments, described by linear or quadratic function (r2 = 0.72 to 0.99), were not different among genotypes. No interactions between soil N treatments and RN based on physiological and growth traits were observed at the time of harvesting. In both projects, resistant genotypes suppressed reniform nematode population at the time of harvesting. RN resistant lines have no biological significant effect on plant growth, development, or yield but do suppress RN populations.
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A study of genetic factors that determine clinical phenotype in skin cancer : basal cell carcinoma and malignant melanomaIchii-Jones, Fumiyo January 2000 (has links)
No description available.
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On temperature-related mortality in an elderly population and susceptible groupsOudin Åström, Daniel January 2014 (has links)
Background: Climate change has increased the frequency, intensity, duration, and spatial extent of some extreme weather events, for instance heat waves. Societies today are experiencing an ongoing change in the population structure yielding an increasing proportion elderly due to increased longevity, resulting in higher prevalence of chronic and degenerative diseases. Literature suggests that the elderly and certain susceptible subgroups with chronic disease are among the most vulnerable to heat waves and elevated temperatures. Aim: The main aims of this thesis were to expand the scientific knowledge on the short-term effects of extreme heat on mortality for the general population and certain susceptible groups in society, to investigate the development of this relationship over time and to attribute mortality to observed climate change. Methods: Daily numbers of deaths and daily meteorological observations during three different periods were collected for present day Stockholm County, Sweden. The analyses of the relationship between mortality and temperature extremes were analysed using a time series approach. The regression models assumed the daily counts of mortality to follow an overdispersed Poisson distribution and adjustments were made for time-trends as well as confounding factors. Results: The literature review of recent studies identified a strong relationship between heat and heat waves and increasing death rates among the elderly, particularly for respiratory and cardiovascular mortality. A statistically significant increase in total daily mortality during heat extremes in all decades investigated, as well as over the entire period, during the period 1901-2009 with a declining trend over time for the relative risk associated with heat extremes, was reported in paper II. For the period 1901-2009 cold extremes significantly increased mortality, with a more disperse pattern over individual decades and no declining trend over time. Paper III attributed increased mortality due to climate change between 1900-1929 and 1980-2009. This increase was mainly due to a large number of excess heat extremes in the latter time period. Furthermore certain subgroups of the population above 50, were in paper IV found to have significantly increased mortality during heat waves as compared to non-heat wave days. Conclusions: Although the relative risk of dying during extreme temperature events appears to have fallen in Stockholm, Sweden, such events still pose a threat to public health. The elderly population and certain susceptible subgroups of the population experience higher relative risks of dying on heat waves days as compared to normal summer days. Some of the groups most susceptible during heat waves were identified. In order to minimize future impacts of heat waves on public health, identifying susceptible subgroups in an ageing society as well as develop strategies to reduce the impact of future temperature extremes on public health will be important.
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Resistência, resiliência e sensibilidade de ovinos ao Haemonchus contortus: comparações hematológicas e bioquímicas / Resistance, resilience and sensitivity of sheep to Haemonchus contortus: hematological and biochemical comparisonsStorillo, Vanessa Martins 15 December 2016 (has links)
Por ser um parasita hematófago, Haemonchus contortus é modelo para estudo da anemia verminótica em ovinos. A presente pesquisa objetivou analisar as diferenças hematológicas e bioquímicas entre ovinos resistentes, resilientes e sensíveis, e propor a utilização das variações do hematócrito e do teor de hemoglobina durante o período de infecção com H. contortus para agrupar os animais nessas categorias. Para tal, 32 ovinos adultos da raça White Dorper foram infectados com 10.000 larvas L3 de H. contortus em bolus. Nos dias 0, 1, 4, 7, 14, 21, 28 e 34 após a infecção foram realizados: exames clínicos, hemograma, leucograma, perfil bioquímico e contagem de ovos por grama de fezes (OPG). O abate dos animais ocorreu no dia 35 para contagem de parasitas no abomaso. Utilizou-se a variação entre o hematócrito inicial e o final associada à contagem total de parasitas adultos no abomaso para classificar 21 animais em resistentes, resilientes e sensíveis. Verificou-se que as variações do hematócrito e do teor de hemoglobina ao longo do período de parasitismo são mais eficazes em descrever as respostas dos ovinos do que os valores do hematócrito e hemoglobina em si. Durante os primeiros 30 dias de hemoncose os ovinos resilientes mantém o equilíbrio entre produção e perda de hemácias, não ocorrendo envio de células imaturas para a corrente sanguínea. Em oposição, os sensíveis desenvolvem anemia sem sinais de regeneração e sem diminuição do ferro sérico o que denota uma possível falta ou insuficiência de resposta da medula óssea. Nesse período, o leucograma não apresenta especificidades que possam ser atribuídas a características de resistência, resiliência ou sensibilidade. Ocorreu diminuição de proteína total, albumina, beta-hidroxibutirato, triglicérides e movimentos ruminais, portanto menor produtividade, em todos os animais, incluído os resistentes, o que permite recomendar que os ovinos sejam mantidos em ausência de verminose / Haemonchus contortus is a hematophagous parasite, it is a model for the study of verminous anemia in sheep. The present study aimed to analyze the hematological and biochemical differences between resistant, resilient and sensitive sheep and to propose the use variations of hematocrit and hemoglobin content during the infection period with H. contortus to group the animals in these categories. For this, 32 adult White Dorper sheep were infected with 10,000 L3 larvae of H. contortus on bolus. On days 0, 1, 4, 7, 14, 21, 28 and 34 post-infection were performed: clinical exams, hemogram, leukogram, biochemical profile and fecal egg count (FEC). The slaughter of the animals occurred on day 35 for counting parasites in the abomasum. The variation between the initial and final hematocrit associated to the total adult parasite count in the abomasum was used to classify 21 animals as resistant, resilient and sensitive. Variations in hematocrit and hemoglobin content over the period of parasitism have been found to be more effective in describing ovine responses than hematocrit and hemoglobin values per se. During the first 30 days of hemonchosis, the resilient sheep maintains the balance between production and loss of red blood cells, and there is no release of immature cells into the bloodstream. In contrast, the susceptible individuals develop anemia with no signs of regeneration and no decrease in serum iron, which indicates a possible lack or insufficiency of bone marrow response. In this period, the leukogram does not present specificities that can be attributed to characteristics of resistance, resilience or sensitivity. There was decrease in total protein, albumin, beta-hydroxybutyrate, triglycerides and ruminal movements, thus lower productivity, in all animals, including the resistant ones, which allows to recommend keep sheep in the absence of verminose
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Hospedabilidade de Meloidogyne enterolobii em diferentes esp?cies vegetais no Estado do Rio de Janeiro / Hosted Meloidogyne enterolobii in different plant species in the State of Rio de JaneiroMARQUES, M?nica Lau da Silva 31 January 2012 (has links)
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Previous issue date: 2012-01-31 / CAPES / Meloidogyne enterolobii (M. mayaguensis) is nematode specie found in several Brazilian states, parasitizing guavas and other crops. This work aimed to evaluate the reaction of thirty-two plants species to M. enterolobii in the State of Rio de Janeiro. The experiment was conducted in the greenhouse conditions. The population of the M. enterolobiii used in this study was obtained from roots of guava cv. ?Paluma? infested from the municipality of S?o Jo?o da Barra - RJ. The inoculum was multiplied in tomato (Solanum Lycoperyicum) cv. TRural I grown in containers of two liters, with previously autoclaved substrate, which received 5.000 eggs/juveniles/plant. Assessments were made at 90 days after inoculation. Plant roots were processed using Hussey and Barker technique and the population of eggs, juveniles and adults were estimated with the help of Peters counting chamber under an optical microscope. It was determined the final population (Pf) and the reproduction factor (RF), defined as the ratio Pf/Pi, where Pi is the initial population. From the thirty-two plants analyzed, fifteen were susceptible: zucchini (Curcubita moschata Duch), loofah (Luffa cylindrica), white bottlebrush (Callistemon rigidus R. Br), red bottlebrush (Callistemon rigidus R. Br), Brazilian guave (Psidium guineensis), sugarcane var. RB 956911(Saccharum hybrid var. RB 956911), sugarcane var. RB 867515 (Saccharum hybrid var. RB 867515), sugarcane var. RB 92579 (Saccharum hybrid var. RB 92579), sugarcane var. SP 801816 (Saccharum hybrid var. SP 801816), antlerpepper (Capsicum baccatum), hotpepper (Capsicum chinense), tomato cv. TRural I (Solanum lycopersycum cv. TRural I), fis?lia (Physalis angulata), scarlet eggplant (Solanum gilo) and eggplant (Solanum melogena L.). Two were immune: ornamental eucalyptus (Eucalyptus tereticornis) and ox guava (Eugenia stipilata); and fifteen were resistant: count the fruit (Annona squamosa), curly parsley (Petroselinum crispum), pearl pineapple (Ananas cosmosus L. Merril), purple basil (Ocimum pupuraceus), cambuci (Campomanesia phaea), fragrant eucalyptus (Eucalyptus citriodora), eucalyptus (Eucalyptus grandis), pear guava (Psidium acutangulum), yellow guava (Psidium cattleyanum), purple guava (Psidium myrtoides), biribiri (Averrhoa bilimbi L), carambola (Averrhoa carambola L), yellow passionflower (Passiflora maliformis L), rattlepod (crotalaria juncea L) e gray mucuna (Mucuna cin?rea cv. gray mucuna ). / Meloidogyne enterolobii (M. mayaguensis) ? uma esp?cie de nemat?ide encontrado em v?rios estados brasileiros, parasitando goiabeiras e outras plantas cultivadas. Este trabalho teve como objetivo avaliar a hospedabilidade de trinta e duas esp?cies vegetais quanto ? rea??o ao M. enterolobii no Estado do Rio de Janeiro. O experimento foi conduzido em casa de vegeta??o do Instituto de Biologia, no Departamento de Entomologia e Fitopatologia da Universidade Federal Rural do Rio de Janeiro. A popula??o do in?culo inicial do M. enterolobii utilizada foi obtida em campo a partir de ra?zes de goiabeira cv. ?Paluma? infestadas, proveniente do munic?pio de S?o Jo?o da Barra ? RJ. O in?culo foi multiplicado em tomateiro (Solanum Lycopersycum) cv. TRural I cultivadas em vasos de dois litros, com substrato previamente autoclavado, que receberam 5.000 ovos/juvenis/planta. As avalia??es ocorreram aos 90 dias ap?s a inocula??o. As ra?zes das plantas foram processadas utilizando a t?cnica de Hussey e Barker adaptada por Bonnetti e Ferraz (1981) e a popula??o de ovos, juvenis e adultos foram estimada com aux?lio da c?mara de contagem de Peters, sob microsc?pio ?ptico. Os dados obtidos constitu?ram a popula??o final (Pf) e foram utilizados na determina??o do fator de reprodu??o (FR), conforme Collen e D?Herde (1972), definido pela rela??o Pf/Pi, em que Pi ? a popula??o inicial. Das trinta e duas plantas analisadas, quinze foram suscet?veis: abobrinha menina brasileira (Curcubita moschata Duch), bucha (Luffa cylindrica), escova-de-garrafa branca (Callistemon rigidus R. Br), escova-de-garrafa vermelho (Callistemon rigidus R. Br), ara?? (Psidium guineensis), cana-de-a??car var. RB956911 (Saccharum hibrido var. RB956911), cana-de-a??car var. RB 867515 (Saccharum hibrido var. RB 867515), cana-de-a??car var. RB 92579 (Saccharum hibrido var. RB 92579), cana-de-a??car var. SP 801816 (Saccharum hibrido var. SP 801816), pimenta chifre de veado (Capsicum baccatum), pimenta bode (Capsicum chinense), tomate cv. TRural I (Solanum lycopersycum) cv TRural I, f?salis (Physalis angulata), jil? (Solanum gilo) e a berinjela (Solanum melogena L.). Dois foram imunes: eucalipto ornamental (Eucalyptus tereticornis) e o ara?? boi (Eugenia stipilata); e quinze foram resistentes: fruta do conde (Annona squamosa), salsa-crespa (Petroselinum crispum), abacaxi perola (Ananas cosmosus L. Merril), manjeric?o roxo (Ocimum pupuraceus), cambuci (Campomanesia phaea), eucalipto cheiroso (Eucalyptus citriodora), eucalipto (Eucalyptus grandis), ara?? p?ra (Psidium acutangulum), ara??-amarelo (Psidium cattleyanum), ara?? roxo (Psidium myrtoides), biribiri (Averrhoa bilimbi L), carambola (Averrhoa carambola L), maracuj? amarelo (Passiflora maliformis L), crotalaria juncea (crotalaria juncea L) e mucuna cinza (Mucuna cin?rea cv. Mucuna cinza).
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Resistência, resiliência e sensibilidade de ovinos ao Haemonchus contortus: comparações hematológicas e bioquímicas / Resistance, resilience and sensitivity of sheep to Haemonchus contortus: hematological and biochemical comparisonsVanessa Martins Storillo 15 December 2016 (has links)
Por ser um parasita hematófago, Haemonchus contortus é modelo para estudo da anemia verminótica em ovinos. A presente pesquisa objetivou analisar as diferenças hematológicas e bioquímicas entre ovinos resistentes, resilientes e sensíveis, e propor a utilização das variações do hematócrito e do teor de hemoglobina durante o período de infecção com H. contortus para agrupar os animais nessas categorias. Para tal, 32 ovinos adultos da raça White Dorper foram infectados com 10.000 larvas L3 de H. contortus em bolus. Nos dias 0, 1, 4, 7, 14, 21, 28 e 34 após a infecção foram realizados: exames clínicos, hemograma, leucograma, perfil bioquímico e contagem de ovos por grama de fezes (OPG). O abate dos animais ocorreu no dia 35 para contagem de parasitas no abomaso. Utilizou-se a variação entre o hematócrito inicial e o final associada à contagem total de parasitas adultos no abomaso para classificar 21 animais em resistentes, resilientes e sensíveis. Verificou-se que as variações do hematócrito e do teor de hemoglobina ao longo do período de parasitismo são mais eficazes em descrever as respostas dos ovinos do que os valores do hematócrito e hemoglobina em si. Durante os primeiros 30 dias de hemoncose os ovinos resilientes mantém o equilíbrio entre produção e perda de hemácias, não ocorrendo envio de células imaturas para a corrente sanguínea. Em oposição, os sensíveis desenvolvem anemia sem sinais de regeneração e sem diminuição do ferro sérico o que denota uma possível falta ou insuficiência de resposta da medula óssea. Nesse período, o leucograma não apresenta especificidades que possam ser atribuídas a características de resistência, resiliência ou sensibilidade. Ocorreu diminuição de proteína total, albumina, beta-hidroxibutirato, triglicérides e movimentos ruminais, portanto menor produtividade, em todos os animais, incluído os resistentes, o que permite recomendar que os ovinos sejam mantidos em ausência de verminose / Haemonchus contortus is a hematophagous parasite, it is a model for the study of verminous anemia in sheep. The present study aimed to analyze the hematological and biochemical differences between resistant, resilient and sensitive sheep and to propose the use variations of hematocrit and hemoglobin content during the infection period with H. contortus to group the animals in these categories. For this, 32 adult White Dorper sheep were infected with 10,000 L3 larvae of H. contortus on bolus. On days 0, 1, 4, 7, 14, 21, 28 and 34 post-infection were performed: clinical exams, hemogram, leukogram, biochemical profile and fecal egg count (FEC). The slaughter of the animals occurred on day 35 for counting parasites in the abomasum. The variation between the initial and final hematocrit associated to the total adult parasite count in the abomasum was used to classify 21 animals as resistant, resilient and sensitive. Variations in hematocrit and hemoglobin content over the period of parasitism have been found to be more effective in describing ovine responses than hematocrit and hemoglobin values per se. During the first 30 days of hemonchosis, the resilient sheep maintains the balance between production and loss of red blood cells, and there is no release of immature cells into the bloodstream. In contrast, the susceptible individuals develop anemia with no signs of regeneration and no decrease in serum iron, which indicates a possible lack or insufficiency of bone marrow response. In this period, the leukogram does not present specificities that can be attributed to characteristics of resistance, resilience or sensitivity. There was decrease in total protein, albumin, beta-hydroxybutyrate, triglycerides and ruminal movements, thus lower productivity, in all animals, including the resistant ones, which allows to recommend keep sheep in the absence of verminose
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Improving Infectious Disease Transmission Models that Account for Variations in Transmissibility and Behavior31 December 2019 (has links)
archives@tulane.edu / We extend the conventional models in mathematical epidemiology to account for more practical (yet complicated) situations in infectious disease transmissions, such as behavior change, risk level differentiation and infectiousness as a function of time since infection. We allow the transmission rate and recovery rate to vary as functions of time since infection. We present the derivation of the integral differential equation model and analyze the associated analytical and long-time solutions. We prove the well-posedness of an initial boundary value problem for the model. We also derive the threshold quantities for the epidemic to grow. We then extend the approach for the vector-borne infectious disease models. We compare several risk distribution functions due to geographic reasons. We construct the behavior change factor for the host population to account for different levels of infectiousness due to behavior distinction and behavior change. We establish the well-posedness of an initial boundary value problem of the new model. Sensitivity analysis shows that different risk distribution functions that are designed to adjust for spatial and geographic reasons have a large impact on the solution. / 1 / Li Guan
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A Comparison of Internal Bicarbonate of Some Chlorosis-Resistant and Chlorosis-Susceptible PlantsClark, Ralph Barlow 01 May 1959 (has links)
Iron chlorosis has been a serious problem for many years. This physiological disease has occurred so frequently on calcareous soils that it has been called lime-induced chlorosis by many of the workers. Because the western United States has so many soils of this type, the chlorosis problem has been of primary concern. Untold economic losses have been the result of this physiological disease.
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A Histopathological Study of Rhizoctonia Solani Kuhn Infection of Resistant and Susceptible Lines of Lima Bean (Phaseolus Limensis Macf.)Bunnag, Chulevan 01 May 1969 (has links)
The effects of Rhizoctonia solani on the hypocotyls of resistant and susceptible lines of lima bean were studied . The fungus attacks lima bean at one or more stages during host development and causes pre-and -postemergence damping-off, root rot, and foliage blight. The isolate of the fungus used in this study was obtained from infected radishes grown in Salt Lake County. Utah.
The formation of infection cushions and modes of penetration by this fungus was no different on the resistant and susceptible lima bean hypocotyls . The infection process was studied under laboratory conditions . Differential staining showed that the fungal hyphae were closely appressed to the host surface , and at first along the longitudinal axis o f the epidermal cells. Later, hyphal branches grew in oblique and transverse directions . Aggregated hyphal tips formed infection cushions , which gave rise to one or more infection pegs that penetrated the host directly . Following penetration, both intercellular and intracellular hyphae were formed. The build-up of masses of hyphae occurred as club-shaped structures in the cortex of the susceptible lima bean hypocotyls , but were not observed in the resistant hypocotyls . The extents of infection in the resistant and susceptible lima bean hypocotyls were different at 7 days after inoculation. The hyphae in the susceptible hypocotyl had penetrated into vascular bundles and pith , whereas the hyphae had penetrated the cortex and pith of the resistant hypocotyl but were not observed in the vascular tissue.
Stomatal penetration from individual hyphal side branches was rare and apparently of minor importance as a means of penetration by this isolate .
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