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Effects of Imazapyr and prescribed fire on vegetation and bird communities in mid-rotation CRP pine plantations of MississippiSingleton, Lindsey Rae Carpenter 03 May 2008 (has links)
Appropriate management of mid-rotation pine plantations can improve habitat for early successional and pine-grassland adapted avian species. I tested effects of Imazapyr selective herbicide and prescribed fire on plant and avian communities in thinned, mid-rotation pine stands contracted under the Conservation Reserve Program. Within 12 replicate sites, 2 8.1-ha plots were assigned either herbicide and prescribed fire treatment or control. I described components of vegetation structure and composition in 2006. I tested effects of herbicide and prescribed fire treatment on avian relative abundance, species richness, total avian conservation value, and density of select species during 2003 - 2006. Hardwood midstory decreased and abundances of grasses and forbs increased following treatment. A shift occurred in the bird community from closed-canopy forest species to early successional and pine-grassland species. Treatment stands benefited many avian species exhibiting negative population trends.
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Avian Use Of Riparian Habitats And The Conservation Reserve Program: Migratory Stopover In AgroecosystemsCashion, Erin Brooke 06 September 2011 (has links)
No description available.
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Controlled radical polymerization of vinyl esters and vinyl amides : experimental and theoretical studies / Polymérisation radicalaire contrôlée d'esters et d'amides de vinyle : études expérimentales et théoriquesMorin, Aurélie 06 November 2013 (has links)
Ces travaux de thèse portent sur la polymérisation radicalaire contrôlée (PRC) des esters et amides de vinyle. L’une des possibilités de contrôle est le piégeage dynamique réversible des chaînes radicalaires croissantes (P•) par un agent de contrôle (T) formant une espèce dormante (P─T’). La concentration en radicaux dans le milieu peut alors diminuer dramatiquement de sorte que les réactions indésirables de terminaisons soient négligeables et que le contrôle de la masse molaire des polymères soit atteint avec un faible indice de dispersité. L’utilisation de complexes métalliques, pouvant s’oxider et former une liaison métal-carbone, comme agent de piégeage des radicaux est une manière de réaliser ce contrôle. La PRC est alors appelée Polymérisation Radicalaire Contrôlée par voie Organométallique (OMRP). A ce jour, plusieurs métaux de transitions ont été utilisés avec plus ou moins de succès en OMRP. Lors de cette étude, nous avons synthétisé des complexes de cuivre(I) et testé leurs performances pour l’OMRP de l’acétate de vinyle et de l’éthylène. Nous avons également utilisé des outils de chimie théorique pour mieux comprendre pourquoi le cobalt(II) acétylacétonate est, jusqu’à aujourd’hui, le meilleur agent de contrôle pour la polymérisation de l’acétate de vinyle et des amides de vinyle. Grâce à la théorie de la fonctionnelle de densité (DFT), nous avons mis en lumière le rôle crucial de la coordination sur le cobalt des groupements carbonyles des monomères étudiés. / This thesis focus on Controlled Radical Polymerization (CRP) of vinyl esters and vinyl amides. One of the possibilities to achieve this control is a dynamic reversible trapping of the growing radical chains (P•) by a controlling agent (T) to form a dormant species (P─T’). The radical concentration in the medium can be dramatically reduced so that the unwanted terminations are disfavored and polymers with controlled molecular weights and low dispersity can be obtained. A way to achieve this control is the use of metallic complexes, which can oxidize and form a metal-carbon bond, as trapping agent in the so-called Organometallic Mediated Radical Polymerization (OMRP). So far, different transition metals have been used with gretaer or smaller success. In this study, the synthesis of copper(I) complexes and their investigation for the vinyl acetate and ethylene polymerization under OMRP conditions were performed. We also used computational chemistry as a tool to better understand why the cobalt(II) acetylacetonate (Co(acac)2) has, so far, given the best results for either vinyl acetate or vinyl amides polymerization. Thanks to Density Functional Theory (DFT), the crucial role of the monomer carbonyl group coordination to cobalt was pointed out.
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Abdominal Aortic Aneurysm : Experience from a Screening Study in Northern SwedenWanhainen, Anders January 2004 (has links)
<p>Abdominal aortic aneurysm (AAA) is a common problem with life-threatening consequences and was suspected to be a serious health problem in Norsjö, a municipality in northern Sweden. A screening study was undertaken to investigate the prevalence, risk factors associated with AAA and the effect of screening on quality of life (QoL). All men and women, aged 65-75 years, were invited to an ultrasonography (US) examination, 91% attended and 92 subjects were also evaluated with computed tomography (CT).</p><p>Depending on diagnostic criteria, the AAA prevalence was 3.6-16.9% in men and 0.8-9.4% in women. Seventy-five percent of the differences between US- and CT anteroposterior measurements were less than 5 mm. A decrease in mental health was observed among AAA patients with low baseline SF-36 scale scores. Elevated cholesterol at age 60 years were associated with screening detected AAA after 12 years of follow-up. Smoking, atherosclerosis and having a first degree relative with AAA were associated with AAA at screening. Compared to blood samples obtained 12 years prior to screening an elevation of hsCRP over time was observed among AAA patients. </p><p>Based on a systematic review of the literature, different screening strategies were analysed in a Markov cohort model. The cost per life year gained ranged from $8 309 to $14 084 and was estimated to $10 474 when 65 year old men were screened once.</p><p>Conclusions: The highest prevalence of AAA ever reported, in a population-based screening program, was found in Norsjö. The risk of having an AAA at screening showed a strong but complex association with atherosclerosis and its risk factors, genetic and inflammatory mechanisms may also be important. Screening 65-year-old men for AAA may be cost-effective, but QoL aspects on the cost-effectiveness of AAA screening merits further investigation.</p>
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Abdominal Aortic Aneurysm : Experience from a Screening Study in Northern SwedenWanhainen, Anders January 2004 (has links)
Abdominal aortic aneurysm (AAA) is a common problem with life-threatening consequences and was suspected to be a serious health problem in Norsjö, a municipality in northern Sweden. A screening study was undertaken to investigate the prevalence, risk factors associated with AAA and the effect of screening on quality of life (QoL). All men and women, aged 65-75 years, were invited to an ultrasonography (US) examination, 91% attended and 92 subjects were also evaluated with computed tomography (CT). Depending on diagnostic criteria, the AAA prevalence was 3.6-16.9% in men and 0.8-9.4% in women. Seventy-five percent of the differences between US- and CT anteroposterior measurements were less than 5 mm. A decrease in mental health was observed among AAA patients with low baseline SF-36 scale scores. Elevated cholesterol at age 60 years were associated with screening detected AAA after 12 years of follow-up. Smoking, atherosclerosis and having a first degree relative with AAA were associated with AAA at screening. Compared to blood samples obtained 12 years prior to screening an elevation of hsCRP over time was observed among AAA patients. Based on a systematic review of the literature, different screening strategies were analysed in a Markov cohort model. The cost per life year gained ranged from $8 309 to $14 084 and was estimated to $10 474 when 65 year old men were screened once. Conclusions: The highest prevalence of AAA ever reported, in a population-based screening program, was found in Norsjö. The risk of having an AAA at screening showed a strong but complex association with atherosclerosis and its risk factors, genetic and inflammatory mechanisms may also be important. Screening 65-year-old men for AAA may be cost-effective, but QoL aspects on the cost-effectiveness of AAA screening merits further investigation.
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Biomarcadores de sepsis en sangre de cordón para el diagnóstico de sepsis neonatal precozSancho Rodríguez, Natalia 23 July 2012 (has links)
La sepsis neonatal precoz actualmente es una importante causa de morbilidad y mortalidad en el período neonatal, y su rápido diagnóstico puede ayudar a instaurar un tratamiento antibiótico eficaz.
El objetivo de este trabajo es estudiar la relación de diferentes marcadores de sepsis, tanto bioquímicos como hematológicos, en muestras de sangre de cordón procedentes de neonatos; que previamente fueron clasificados en grupos de estudio en función de la presencia o ausencia de factores de riesgo (infeccioso, prematuridad, otras causas, o sepsis neonatal precoz confirmada).
Los marcadores bioquímicos de sepsis (PCR, PCT e IL-6) y hematológicos en sangre de cordón no han resultado de utilidad en el diagnóstico de sepsis neonatal precoz, y los datos clínicos continúan siendo los más determinantes. Las nuevas técnicas de biología molecular en sangre de cordón fueron indicativas de la presencia de sospecha de infección en aquellos neonatos con uno o varios factores de riesgo infeccioso. / Early-onset neonatal sepsis is currently a major cause of morbidity and mortality in the neonatal period, and its rapid diagnosis can help to establish an effective antibiotic treatment. The objective of this work is to study the relationship of different markers of sepsis, both biochemical and haematological, in cord blood samples taken from infants; that were previously classified in groups according to the presence or absence of risk factors (infectious, prematurity, other causes, or confirmed early neonatal sepsis).
Biochemical markers sepsis (CRP, PCT and IL-6) and haematological in cord blood have not proved useful in the diagnosis of early neonatal sepsis, and clinical data continue to be the most decisive. New techniques of molecular biology in cord blood were indicative of the presence of suspected infection in those neonates with one or several factors of risk of infection.
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Régulation de la lipoprotéine lipase macrophagique et de LOX-1 par des facteurs métaboliques. Implications dans l’athérosclérose associée au diabète de type 2.Maingrette, Fritz 12 1900 (has links)
Les maladies cardiovasculaires (MCV) sont la principale cause de décès dans les pays occidentaux et constituent la principale complication associée au diabète. La lipoprotéine lipase (LPL) est une enzyme clé du métabolisme des lipides et est responsable de l'hydrolyse des lipoprotéines riches en triglycérides (TG). Plusieurs études ont démontré que la LPL sécrétée par les macrophages dans la paroi artérielle est pro-athérogénique.
La dysfonction endothéliale caractérise les stades précoces du processus athérosclérotique. Il a été observé qu’un récepteur nouvellement identifié des lipoprotéines de basse densité oxydées (LDLox), le récepteur de type lectine des LDLox (LOX-1), est fortement exprimé dans les lésions athérosclérotiques humaines et dans l’aorte de rats diabétiques, suggérant un rôle clé de LOX-1 dans la pathogénèse de l’athérosclérose diabétique.
Au vu du rôle potentiel de la LPL macrophagique et du LOX-1 dans l’athérosclérose associée au diabète de type 2, nous avons évalué la régulation de ces deux molécules pro-athérogéniques par des facteurs métaboliques et inflammatoires augmentés dans le diabète, soit la leptine, l’acide linoléique (LA) et la protéine C-réactive (CRP). Nos résultats démontrent que : 1) Dans les cellules endothéliales aortiques humaines (HAECs), LA augmente l’expression protéique de LOX-1 de façon temps- et dose-dépendante; 2) La pré-incubation de HAECs avec des antioxydants et des inhibiteurs de la NADPH oxydase, de la protéine kinase C (PKC) et du facteur nucléaire-kappa B (NF-kB), inhibe l’effet stimulant de LA sur l’expression protéique de LOX-1; 3) Dans les HAECs traitées avec LA, on observe une augmentation d’expression des isoformes classiques de la PKC; 4) LA augmente de manière significative l’expression génique de LOX-1 ainsi que la liaison des protéines nucléaires extraites des HAECs à la séquence régulatrice NF-kB présente dans le promoteur du gène de LOX-1; 5) LA augmente, via LOX-1, la captation des LDLox par les cellules endothéliales. Pris dans leur ensemble, ces résultats démontrent que LA augmente l’expression endothéliale de LOX-1 in vitro et appuient le rôle clé de LA dans la dysfonction endothéliale associée au diabète.
Au vu de nos études antérieures démontrant qu’une expression accrue de LPL macrophagique chez les patients diabétiques de type 2 et que l’augmentation de facteurs métaboliques dans cette maladie, soit l’homocystéine (Hcys), les acides gras et les produits terminaux de glycation (AGE), accroissent l’expression de la LPL macrophagique, nous avons par la suite déterminé l’effet, in vitro, de deux autres facteurs métaboliques et inflammatoires surexprimés dans le diabète, soit la leptine et la CRP, sur l’expression de la LPL macrophagique.
Les concentrations plasmatiques de leptine sont élevées chez les patients diabétiques et sont associées à un accroissement des risques cardiovasculaires. Nous avons démontré que : 1) Dans les macrophages humains, la leptine augmente l’expression de la LPL, tant au niveau génique que protéique; 2) L’effet stimulant de la leptine sur la LPL est aboli par la pré-incubation avec un anticorps dirigé contre les récepteurs à la leptine (Ob-R), des inhibiteurs de la PKC et des antioxydants; 3) La leptine augmente l’expression membranaire des isoformes classiques de la PKC et la diminution de l’expression endogène de la PKC, abolit l’effet de la leptine sur l’expression de la LPL macrophagique; 4) Dans les macrophages murins, la leptine augmente le taux de synthèse de la LPL et augmente la liaison de protéines nucléaires à la séquence protéine activée-1 (AP-1) du promoteur du gène de la LPL. Ces observations supportent la possibilité que la leptine puisse représenter un facteur stimulant de la LPL macrophagique dans le diabète.
Finalement, nous avons déterminé, in vitro, l’effet de la CRP sur l’expression de la LPL macrophagique. La CRP est une molécule inflammatoire et un puissant prédicteur d’événements cardiovasculaires. Des concentrations élevées de CRP sérique sont documentées chez les patients diabétiques de type 2. Nous avons démontré que : 1) Dans les macrophages humains, la CRP augmente l’expression de la LPL au niveau génique et protéique et la liaison de la CRP aux récepteurs CD32 est nécessaire pour médier ses effets; 2) La pré-incubation de macrophages humains avec des antioxydants, des inhibiteurs de la PKC et de la protéine kinase mitogénique activée (MAPK), prévient l’induction de la LPL par la CRP; 3) La CRP augmente l’activité de la LPL, la génération intracellulaire d’espèces radicalaires oxygénées (ROS), l’expression d’isoformes classiques de la PKC et la phosphorylation des kinases extracellulaires régulées 1/2 (ERK 1/2); 4) Les macrophages murins traités avec la CRP démontrent une augmentation de la liaison des protéines nucléaires à la séquence AP-1 du promoteur du gène de la LPL. Ces données suggèrent que la LPL puisse représenter un nouveau facteur médiant les effets délétères de la CRP dans la vasculopathie diabétique.
Dans l’ensemble nos études démontrent le rôle clé de facteurs métaboliques et inflammatoires dans la régulation vasculaire de la LPL et du LOX-1 dans le diabète. Nos données suggèrent que la LPL et le LOX-1 puissent représenter des contributeurs clé de l’athérogénèse accélérée associée au diabète chez l’humain.
Mots-clés : athérosclérose, maladies cardiovasculaires, diabète de type 2, macrophage, LPL, cellules endothéliales, LOX-1, stress oxydatif, leptine, LA, CRP. / Atherosclerotic cardiovascular disease is the leading cause of death in western countries and is the major complication of diabetes. Lipoprotein lipase (LPL) is a key enzyme in lipid metabolism, responsible for the hydrolysis of triglyceride (TG) rich lipoproteins. Many studies have shown that LPL secreted by macrophages in the arterial wall is proatherogenic.
Endothelial dysfunction is a characteristic feature of early-stage atherosclerosis. The observation that lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1), a newly identified receptor for oxidized LDL (oxLDL), is highly expressed in human atherosclerotic lesions and upregulated in the aorta of diabetic rats, suggests a key role for LOX-1 in the pathogenesis of diabetic atherosclerosis.
Based on the role of macrophage LPL and LOX-1 in atherosclerosis, we sought to investigate the regulation of these two proatherogenic molecules by metabolic and inflammatory factors dysregulated in diabetes namely leptin, linoleic acid (LA) and C-reactive protein (CRP). Our results demonstrated that: 1) In human aortic endothelial cells (HAECs), LA increased LOX-1 protein expression in a time- and dose-dependent manner; 2) Pretreatment of HAECs with antioxidants and inhibitors of NADPH oxidase, protein kinase C (PKC), and nuclear factor-kB (NF-kB) inhibited the stimulatory effect of LA on LOX-1 protein expression; 3) Increased expression of classic PKC isoforms was observed in LA-treated HAECs; 4) LA led to a significant increase in LOX-1 gene expression and enhanced the binding of nuclear proteins extracted from HAECs to the NF-kB regulatory element of the LOX-1 gene promoter; 5) LA enhanced, through LOX-1, oxLDL uptake by endothelial cells. Overall, these results demonstrated that LA enhances endothelial LOX-1 expression in vitro and support a key role for LA in endothelial dysfunction associated with diabetes.
Based on our previous studies showing that macrophage LPL expression is increased in patients with type 2 diabetes and that metabolic factors dysregulated in this disease such as glucose, homocysteine (Hcys), fatty acids and advanced glycation end products (AGE), increased macrophage LPL expression, we next determined the effect of two other metabolic and inflammatory factors dysregulated in diabetes, namely leptin and CRP, on macrophage LPL expression in vitro.
Leptin levels are elevated in diabetic patients and are associated with greater cardiovascular risks. We found that: 1) In human macrophages, leptin increased LPL expression, at both the gene and protein levels; 2) The stimulatory effect of leptin on LPL was abolished by pre-treatment with anti-leptin receptor (Ob-R) antibody, PKC inhibitors and antioxidants; 3) Leptin increased the membrane expression of conventional PKC isoforms and downregulation of endogenous PKC expression abolished the effects of leptin on macrophage LPL expression; 4) In murine macrophages, leptin raised LPL synthetic rate and enhanced the binding of nuclear proteins to the activated protein-1 (AP-1) sequence of the LPL gene promoter. These observations support the possibility that leptin may represent a macrophage LPL stimulatory factor in diabetes.
Finally, we sought to determine the effect of CRP on macrophage LPL expression in vitro. CRP is an inflammatory molecule and a strong predictor of cardiovascular events and high serum levels of CRP are observed in type 2 diabetic patients. We found that: 1) In human macrophages, CRP increased LPL expression at the gene and protein levels and CRP binding to CD32 receptors is required for these effects; 2) Preincubation of human macrophages with antioxidants, PKC and mitogen-activated protein kinase (MAPK) inhibitors, prevented the CRP-induced LPL expression; 3) CRP increased LPL activity, intracellular reactive oxygen species (ROS) generation, classic PKC isozymes expression and extracellular signal-regulated protein kinase (ERK) 1/2 phosphorylation; 4) CRP-treated murine macrophages demonstrated increased binding of nuclear proteins to the AP-1 sequence of the LPL gene promoter. These data suggest that LPL might represent a novel factor underlying the adverse effect of CRP on the diabetic vasculature.
Overall, our studies indicate a key role of metabolic and inflammatory factors in the regulation of vascular LPL and LOX-1 in diabetes. Our data suggest that LPL and LOX-1 are key contributors to the accelerated atherogenesis associated with human diabetes.
Keywords : atherosclerosis, cardiovascular diseases, type 2 diabetes, macrophage, LPL, endothelial cells, LOX-1, oxidative stress, leptin, LA, CRP.
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Régulation de la lipoprotéine lipase macrophagique et de LOX-1 par des facteurs métaboliques. Implications dans l’athérosclérose associée au diabète de type 2Maingrette, Fritz 12 1900 (has links)
No description available.
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AVALIAÇÃO DO ESTRESSE OXIDATIVO ATRAVÉS DA DETERMINAÇÃO DE PRODUTOS DA OXIDAÇÃO AVANÇADA DE PROTEÍNAS (AOPP) EM PACIENTES COM ANEMIA MICROCÍTICA E HIPOCRÔMICA / EVALUATION OF OXIDATIVE STRESS BY DETERMINATION OF ADVANCED OXIDATION PROTEIN PRODUCTS (AOPP) IN PATIENTS WITH ANEMIA MICROCYTIC AND HYPOCROMICDanieli, Karina 31 August 2011 (has links)
The etiology of anemia is characterized by abnormal hemoglobin synthesis. Iron
deficiency is characterized by microcytic and hipochromic red cells and low serum
ferritin, being the most prevalent nutritional deficiency worldwide, responsible for iron
deficiency anemia (FA). Anemia of chronic disease (ACD) is considered a clinical
syndrome associated with chronic inflammation, infectious disease, neoplastic or
traumatic, being the second most frequent cause of anemia. The severity of anemia
correlates with the degree of pathology. Both have functional iron deficiency. The
objective of this study was to evaluate hematological and inflammatory, as well as the
presence of oxidative stress in patients with anemia. The blood analyzer was done by
the CBC, automated hematology analyzer processed, Sysmex® (Automated
Hematology Analyzer). The quantitative determination of ferritin is serum was done in
IMMULITE analyzer. Levels of CRP and AOPP were performed in serum by automated
Cobas MIRA® (Roche Diagnostics). Statistical analysis was performed using
GraphPad Prism 5. We analyzed 70 patients with microcytic and hypochromic anemia.
Of these, 29 (41.43%) were diagnosed as iron deficiency anemia and 41 (58.57%) with
anemia of chronic disease. As a control group, we used samples from 44 patients with
hematological parameters, serum ferritin, CRP and AOPP normal. The values of MCV,
MCH and MCHC significantly lower in iron deficiency anemia. Ferritin levels showed
that it can be considered both a measure of iron store as an inflammatory marker. In
ACD there is increased production of inflammatory cytokines, which, in turn, increases
the concentration of C-reactive protein (CRP). The results indicate that AOPP in both
groups with anemia showed increased levels of this marker, which indicates the
presence of oxidative stress, probably caused by increased production of free radicals
and decreases in enzyme activities of the antioxidant defense system of erythrocytes. / A etiologia das anemias caracteriza-se pela síntese anormal de hemoglobina. A
deficiência de ferro é caracterizada por eritrócitos microcíticos e hipocrômicos e por
ferritina sérica baixa, sendo a carência nutricional mais prevalente em todo o mundo,
responsável pela Anemia Ferropriva (AF). A Anemia de Doença Crônica (ADC) é
considerada uma síndrome clínica, associada à inflamação crônica, doença infecciosa,
traumática ou neoplásica, sendo a segunda causa mais freqüente de anemia. Ambas
apresentam deficiência funcional de ferro. O objetivo deste trabalho foi avaliar
parâmetros hematológicos e inflamatórios, bem como a presença de estresse
oxidativo em pacientes com anemia. A análise hematológica foi feita através do
hemograma, processado em analisador hematológico automatizado, Sysmex®
(Automated Hematology Analyzer). O doseamento quantitativo da ferritina no soro foi
feito em analisador IMMULITE. A dosagem de Proteína C-Reativa (PCR) e de
Produtos da Oxidação Avançada de Proteínas (AOPP) foram realizadas no soro
através do sistema automatizado Cobas MIRA® (Roche Diagnostics). A análise
estatística foi realizada através do programa GraphPad Prism 5. Foram analisados 70
pacientes portadores de anemia microcítica e hipocrômica. Destes, 29 (41,43%) foram
diagnosticados como anemia ferropriva e 41 (58,57%) com anemia de doença crônica.
Como grupo controle, foram utilizadas amostras de 44 indivíduos com parâmetros
hematológicos, níveis de ferritina, PCR e AOPP dentro da normalidade. Os valores de
VCM, HCM e CHCM foram significativamente menores na anemia ferropriva. Os níveis
de ferritina revelaram que ela pode ser considerada tanto uma medida das reservas de
ferro quanto um marcador inflamatório. Na ADC há aumento da produção de citocinas
inflamatórias, que, por sua vez, aumenta também a concentração de PCR. Os
resultados do AOPP indicam que ambos os grupos com anemia apresentaram níveis
aumentados deste marcador, o que indica a presença de estresse oxidativo,
provavelmente causado por aumento na produção de radicais livres e declínio das
atividades das enzimas do sistema de defesa antioxidante dos eritrócitos.
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Effects of Acetaminophen on Pain Response among Overweight or Obese Women Exposed to Weight StigmatizationLanders, Jacob David January 2021 (has links)
No description available.
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