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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Avaliação do polimorfismo C677T (ALA222VAL) do gene da metilenotetrahidrofolato redutose (MTHFR) da hemocisteína e-493G/T do gene da proteína microssomal transportadora de triglicerídeos (MTP) em pacientes com hepatite C crônica do Nordeste do Brasil / Methylenetetrahydrofolate reductase (MTHFR) C677T (ALA222VAL) polimorphysm and microsomal triglyceride transfer protein (MTP) -493G/T polymorphism in chronic hepatitis C patients from Northeast of Brazil

Siqueira, Erika Rabelo Forte de 12 September 2011 (has links)
Introdução: A infecção crônica pelo vírus da hepatite C (VHC) está associada à presença da resistência insulínica e da esteatose hepática, independentemente dos fatores metabólicos do hospedeiro. A alteração na enzima MTHFR resulta em hiperhomocisteinemia, que altera o metabolismo intracelular dos lipídios e pode estar relacionada à esteatose hepática e à fibrose, em portadores do VHC. A redução da atividade hepática da MTP resulta em acúmulo de gordura nos hepatócitos, contribuindo para a severidade da esteatose hepática e da fibrose em portadores do VHC. Como objetivos foram estudados os polimorfismos 677 C/T do gene da MTHFR e -493 G/T do gene da MTP e sua relação com as variáveis clínicas, bioquímicas e histológicas em pacientes com infecção crônica pelo VHC. Métodos: 174 pacientes sem tratamento prévio com RNA do VHC positivo e com biópsia hepática foram genotipados para o polimorfismo 677C/T da MTHFR por Restriction Fragment Length Polymorfism-Polimerase Chain (PCRRFLP) e para -493G/T da MTP, por sequenciamento. Todos os pacientes tinham marcadores negativos para doença de Wilson, hemocromatose e doença autoimune, e também tinham baixa ingesta alcoólica, com menos de 100g/semana. Variáveis bioquímicas foram analisadas no momento da realização da biópsia hepática. Resultados: A frequência do genótipo TT do gene MTHFR foi de 9,8% nos pacientes com genótipo não 1 do VHC. No entanto, foi encontrada associação entre o genótipo TT x CT /CC do polimorfismo do gene MTHFR, com o grau de esteatose e fibrose em ambos os genótipos da hepatite C (p < 0,05). Uma diferença significativa foi encontrada em níveis plasmáticos de homocisteína em pacientes com esteatose (p = 0,03). A frequência do genótipo GG+GT do gene MTP foi de 56,8% nos pacientes com genótipo 1 do VHC com fibrose hepática grau 3+4 (OR 1,8, IC 95% 1,3-2,3). Foi observada uma associação direta entre a presença da esteatose hepática nos pacientes com VHC com o genótipo GG+GT do polimorfismo -493G/T do gene da MTP independentemente do genótipo do VHC (OR = 0,4, IC 95% 0,2-0,8, p = 0,01). Conclusões: o genótipo TT do polimorfismo C677T do gene da MTHFR foi mais frequente no genótipo não 1 do VHC, independentemente da classificação histopatológica, assim como a frequência do genótipo CT + TT na presença de fibrose grau 1+ 2 e da esteatose hepática. A hiperhomocisteinemia foi altamente prevalente em indivíduos com esteatose. Por outro lado, a presença do alelo G do do polimorfismo -493G/T do gene da MTP está associada a uma menor expressão da MTP hepática, protegendo contra a esteatose em pacientes com VHC do Nordeste do Brasil. Estudos adicionais em outras populações são necessários para avaliar melhor o papel desses polimorfismos em indivíduos infectados pelo VHC / Background: Chronic hepatitis C (CHC) infection has been shown to promote insulin resistance and hepatic steatosis independent of host metabolic factors. A lower MTHFR activity is associated to hiperhomocysteinemia and also may be related to steatosis and fibrosis in CHC. Futhermore a reduction on hepatic MTP activity resulting in fatty liver and could contribute to the severity of hepatic steatosis and fibrosis in CHC. The aim was to investigate this this polymorphism in the 677 C/T MTHFR and -493G/T MTP genes and there relation with metabolic and histological variables in patients with CHC. Methods: One hundred seven-four untreated patients with viral RNA and liver biopsy were genotyped for the 677C/T MTHFR and 493G/T MTP polymorphisms. The 677C/T polymorphism of the MTHFR gene was identified by Restriction Fragment Length Polymorfism- Polimerase Chain (PCRRFLP) and the 493 G/T polymorphism of the MTP gene was determined by direct sequencing of the polymerase chain reaction products. All patients were negative for markers of Wilsons disease, hemochromatosis and autoimmune diseases and had current and past daily alcohol intake less than 100g/week. A set of metabolic markers were also measured at the time of liver biopsies. Results: Among subjects infected with CHC genotype non-1 the frequency of MTHFR genotypes TT was 9.8%. Nevertheless, association was found between the MTHFR genotype TT x CT/CC polymorphism and the degree of steatosis and fibrosis in both hepatitis C genotype (p < 0.05). A significant difference was found on plasma homocysteine levels in patients with steatosis (p=0.03). Among subjects infected with CHC genotype 1 with fibrosis grade 3+4 the frequency of MTP genotypes GG+GT was 56.8% (OR 1.8; CI 95% 1.3-2.3). Observed an association with steatosis as dependent variable identified in genotypes GG+GT as independent protective factors against steatosis (OR=0.4, CI 95% 0.2-0.8, p = 0.01). Conclusion: The presence of genotype TT of MTHFR C677T polymorphism was more common in CHC genotype non-1 infected patient regardless of histopathological classification and genotype CT+TT frequencies were significant in the presence of fibrosis grade 1+2 and of steatosis. On the other hand the presence of the G allele of MTP 493G/T, which is possibly associated with a lower MTP hepatic expression, protects against steatosis in CHC patients from northeast of Brazil. Additional studies in other populations are needed to further assess the role of this polimorphysm in CHC
52

The interaction of obesity and age and their effect on adipose tissue metabolism in the mouse

Liu, Ke-di January 2019 (has links)
Numerous studies have investigated how bulk lipid metabolism is influenced in obesity and in particular how the composition of triglycerides found in the cytosol change with increased adipocyte expansion. However, in part reflecting the analytical challenge the composition of cell membranes, and in particular glycerophospholipids, an important membrane component, have been seldom investigated. Cell membrane components contribute to a variety of cellular processes including maintaining organelle functionality, providing an optimized environment for numerous proteins and providing important pools for metabolites, such as choline for one-carbon metabolism and S-adenosylmethionine for DNA methylation. Here, I have conducted a comprehensive lipidomic and transcriptomic study of white adipose tissue in mice that become obese either through genetic modification (ob/ob genotype), diet (high-fat diet) or a combination of the two across the life course. Specifically, I demonstrated that the changes in triglyceride metabolism that dominate the overall lipid composition of white adipose tissue were distinct from the compositional changes of glycerophospholipids. These latter lipids became more unsaturated to maintain the fluidity and normal function of the membrane in the initiation of obesity but then turned saturated after long-term administration of HFD and aging. This suggests that while triglycerides within the adipose tissue may be a relatively inert store of lipids, the compositional changes occur in cell membranes with more far-reaching functional consequences in both obesity and aging. The two-phase change of phospholipids can be correlated well with transcriptional and one-carbon metabolic changes within the adipocytes. The transcriptomic study demonstrated that the lipid metabolic pathways regulated by the peroxisome, AMPK, insulin and PPARγ signaling were activated in the initiation of obesity but inhibited in the adipose tissue of old ob/ob mice along with up-regulated inflammation pathways. The brown and white adipose tissue of PPARα-knock-out mice were also studied by lipidomic tools to get a deeper understanding of the effect of the peroxisome and PPAR system on adipose tissue and lipid metabolism during obesity. Most of the lipids were increased and became more saturated and shorter in adipose tissues of PPARα null mice, which is in good accordance with the results of the former animal study. In conclusion, my work using different rodent models and multi-omics techniques demonstrated a protective metabolic mechanism activated in the initiation but impaired at the end of the processes of obesity and aging, which could be an explanation of the similarity of obesity and aging in terms of high incidence of the metabolic syndrome and related diseases.
53

The role of macrophage intracellular lipid partitioning in glucose and lipid homeostasis during obesity

Petkevicius, Kasparas January 2019 (has links)
Obesity-associated metabolic disorders are amongst the most prevalent causes of death worldwide. Understanding how obesity leads to the development of the Metabolic Syndrome (MetS) and cardiovascular disease (CVD) will enable the development of novel therapies that dissociate obesity from its cardiometabolic complications. Our laboratory views the functional capacity of white adipose tissue (WAT), the organ designed for safe lipid storage, as a key factor in the development of MetS and CVD. At a genetically-defined stage of the aberrant WAT expansion that occurs during obesity, adipocytes undergo a functional failure, resulting in an impaired control of serum free fatty acid (FFA) concentration. In such setting, FFAs and their metabolic derivatives accumulate in other organs, where they cause lipotoxicity, leading to the development of insulin resistance and CVD. We therefore aim to understand the pathophysiological mechanisms that induce adipocyte dysfunction. The past two decades of research have established the immune system as an important regulator of WAT function. The number of adipose tissue macrophages (ATMs), the most abundant immune cell type in WAT, increases during obesity, resulting in WAT inflammation. Multiple genetic and pharmacological intervention studies of murine models of obesity have assigned a causal link between ATM pro-inflammatory activation and WAT dysfunction. However, while the propagation of inflammation in ATMs during obesity has been extensively studied, factors triggering ATM inflammatory activation are less clear. Recently, our lab has observed lipid accumulation in the ATMs isolated from obese mice. Lipid-laden ATMs were pro-inflammatory, leading us to hypothesise that aberrant lipid build-up in macrophages triggers WAT inflammation during obesity. This thesis expands on the initial findings from our lab and describes two novel mechanisms that potentially contribute to lipid-induced inflammatory activation of ATMs. In chapter 3, the role of de novo phosphatidylcholine (PC) synthesis pathway during lipotoxicity in macrophages is addressed. The first part of the chapter demonstrates that lipotoxic environment increased de novo PC synthesis rate in bone marrow-derived macrophages (BMDMs) and ATMs, and that loss of rate-limiting enzyme in de novo PC synthesis pathway, CTP:phosphocholine cytidylyltransferase a (CCTa) diminished saturated FFA-induced inflammation in BMDMs. In the second part, I show that macrophage-specific CCTa deletion did not impact on the development of WAT inflammation or systemic insulin resistance, but had a minor benefitial effect on hepatic gene transcription during obesity. Chapter 4 develops on recent observations of interactions between sympathetic nerves and macrophages in WAT. In the first part of the chapter, I demonstrate that stimulating B2-adrenergic receptor (B2AR), the main receptor for sympathetic neurotransmitter norepinephrine in macrophages, enhanced intracellular triglyceride storage by up-regulating diacylglycerol O-acyltransferase 1 (Dgat1) gene expression in BMDMs. The second part of the chapter shows that macrophage-specific B2AR deletion did not modulate systemic glucose and lipid metabolism during obesity, but mice lacking B2ARs in macrophages demonstrated augmented hepatic glucose production on a chow diet. Furthermore, systemic B2AR blockade or macrophage-specific B2AR deletion in mice did not affect the thermogenic response to cold exposure. Chapter 5 includes the characterisation of B2AR stimulation-induced changes to the global cellular proteome of BMDMs, and a subsequent validation of the role of candidate transcription factors in regulating B2AR agonism-induced gene expression in BMDMs.
54

CTRP3 Attenuates Diet-induced Hepatic Steatosis by Regulating Triglyceride Metabolism

Peterson, Jonathan M., Seldin, Marcus M., Wei, Zhikui, Aja, Susan, Wong, G. William 01 August 2013 (has links)
CTRP3 is a secreted plasma protein of the C1q family that helps regulate hepatic gluconeogenesis and is downregulated in a diet-induced obese state. However, the role of CTRP3 in regulating lipid metabolism has not been established. Here, we used a transgenic mouse model to address the potential function of CTRP3 in ameliorating high-fat diet-induced metabolic stress. Both transgenic and wild-type mice fed a high-fat diet showed similar body weight gain, food intake, and energy expenditure. Despite similar adiposity to wild-type mice upon diet-induced obesity (DIO), CTRP3 transgenic mice were strikingly resistant to the development of hepatic steatosis, had reduced serum TNF-α levels, and demonstrated a modest improvement in systemic insulin sensitivity. Additionally, reduced hepatic triglyceride levels were due to decreased expression of enzymes (GPAT, AGPAT, and DGAT) involved in triglyceride synthesis. Importantly, short-term daily administration of recombinant CTRP3 to DIO mice for 5 days was sufficient to improve the fatty liver phenotype, evident as reduced hepatic triglyceride content and expression of triglyceride synthesis genes. Consistent with a direct effect on liver cells, recombinant CTRP3 treatment reduced fatty acid synthesis and neutral lipid accumulation in cultured rat H4IIE hepatocytes. Together, these results establish a novel role for CTRP3 hormone in regulating hepatic lipid metabolism and highlight its protective function and therapeutic potential in attenuating hepatic steatosis.
55

Characterization of the genetic basis in two cases of abetalipoproteinemia reveals two novel mutations

Gunnar, Erika January 2010 (has links)
<p>BACKGROUND: Abetalipoproteinemia (ABL) is a rare autosomal recessive disorder caused by mutations in the gene coding for microsomal triglyceride transfer protein (MTTP).</p><p>AIM: To characterize the genetic basis of ABL in two unrelated patients.</p><p>RESULTS: In the first patient, the substitution c.1911C>T in exon 12 of the <em>MTTP</em> gene, resulting in the protein substitution p.P552L, was discovered using mutation screening. The parents are heterozygous and the proband is a homozygous carrier of this substitution. Using restriction fragment length polymorphism (RFLP), 100 control subjects were analyzed and none carried the substitution indicating that it is a novel <em>MTTP </em>mutation. Sequencing of the other ABL patient showed that the proband carried a homozygous single base insertion, at position  c.2342IVS16+2-3insT, located at the donor splice-site of intron 16 resulting in skipping of exon 16 and truncation of the protein. The proband's mother is heterozygous for the insertion while the father does not carry the insertion. Multiplex ligation-dependent probe amplification (MLPA) did not identify any deletion encompassing exon 16 in the proband, father or mother. Nonpaternity was excluded using polymorphic markers from several chromosomes. Haplotype analysis using markers spanning chromosome 4 revealed  heterodisomy (two homologous chromosomes) of 4p and the distal part of 4q, and isodisomy (duplication of one chromosome) of 4q12-4q26.</p><p>CONCLUSION: These data show that the cause of ABL in one of the patients is a missense mutation, p.P552L, while the cause of ABL in the other patient is due to uniparental disomy, probably resulting from non-disjunstion in meiosis I.</p>
56

Characterization of the genetic basis in two cases of abetalipoproteinemia reveals two novel mutations

Gunnar, Erika January 2010 (has links)
BACKGROUND: Abetalipoproteinemia (ABL) is a rare autosomal recessive disorder caused by mutations in the gene coding for microsomal triglyceride transfer protein (MTTP). AIM: To characterize the genetic basis of ABL in two unrelated patients. RESULTS: In the first patient, the substitution c.1911C&gt;T in exon 12 of the MTTP gene, resulting in the protein substitution p.P552L, was discovered using mutation screening. The parents are heterozygous and the proband is a homozygous carrier of this substitution. Using restriction fragment length polymorphism (RFLP), 100 control subjects were analyzed and none carried the substitution indicating that it is a novel MTTP mutation. Sequencing of the other ABL patient showed that the proband carried a homozygous single base insertion, at position  c.2342IVS16+2-3insT, located at the donor splice-site of intron 16 resulting in skipping of exon 16 and truncation of the protein. The proband's mother is heterozygous for the insertion while the father does not carry the insertion. Multiplex ligation-dependent probe amplification (MLPA) did not identify any deletion encompassing exon 16 in the proband, father or mother. Nonpaternity was excluded using polymorphic markers from several chromosomes. Haplotype analysis using markers spanning chromosome 4 revealed  heterodisomy (two homologous chromosomes) of 4p and the distal part of 4q, and isodisomy (duplication of one chromosome) of 4q12-4q26. CONCLUSION: These data show that the cause of ABL in one of the patients is a missense mutation, p.P552L, while the cause of ABL in the other patient is due to uniparental disomy, probably resulting from non-disjunstion in meiosis I.
57

Purinergic Signaling and Autophagy Regulate the Secretion of High-Density Lipoprotein and Hepatic Lipase

Chatterjee, Cynthia 19 April 2013 (has links)
Dyslipidemia can be a comorbidity of both insulin-resistance and atherosclerosis. Hypertriglyceridemia is common in hyperglycemia and is associated with hypoalphalipoproteinemia (low HDL) and with altered nucleotide or purinergic signaling. We therefore hypothesized that extracellular nucleotides may affect hepatic lipoprotein metabolism. Our studies confirm this view and show that nucleotides regulate cellular proteolytic pathways in liver cells and thereby control lipoprotein secretion and their metabolism by hepatic lipase (HL). Treatment of liver cells with the nucleotide, adenosine diphosphate (ADP), stimulates VLDL-apoB100 and apoE secretion, but blocks HDL-apoA-I and HL secretion. ADP functions like a proteasomal inhibitor to block proteasomal degradation and stimulate apoB100 secretion. Blocking the proteosome is known to activate autophagic pathways. The nucleotide consequently stimulates autophagic degradation in liver cells and increases cellular levels of the autophagic proteins, LC3 and p62. Confocal studies show that ADP increases cellular LC3 levels and promotes co-localization of LC3 and apoA-I in an autophagosomal degradation compartment. ADP acts through the G-protein coupled receptor, P2Y13, to stimulate autophagy and block both HDL and HL secretion. Overexpression of P2Y13 increases cellular LC3 levels and blocks the induction of both HDL and HL secretion, while P2Y13 siRNA reduce LC3 protein levels and cause up to a ten-fold stimulation in HDL and HL secretion. P2Y13 gene expression regulates autophagy through the insulin receptor (IR-β). A reduction in P2Y13 expression increases the phosphorylation of IR-β and protein kinase B (Akt) >3-fold, while increasing P2Y13 expression inhibits the activation of IR-β and Akt. Experiments with epitope-labeled apoA-I and HL show that activation of purinergic pathways has no effect on the internalization and degradation of extracellular apoA-I and HL, which confirms the view that nucleotides primarily impact intracellular protein transport and degradation. In conclusion, elevated blood glucose levels may promote dyslipidemia by stimulating purinergic signaling through P2Y13 and IR-β and perturbing the intracellular degradation and secretion of both HDL and VLDL.
58

Efeitos da dieta cetogênica à base de trienantina nos episódios convulsivos de ratos portadores de epilepsia induzida por pilocarpina / Effects of the ketogenic diet based on triheptanoin in sezures of rats with epilepsy induced by pilocarpine

Gomes, Tâmara Kelly de Castro 15 February 2011 (has links)
The main importance of temporal lobe epilepsy due to its high prevalence and high proportion of patients with refractory epilepsy to treatment, making it necessary in this case, the use of alternative therapies, such as the ketogenic diet. This diet is rich in fat, low in carbohydrates and proteins, and since 1921 has been used for patients unresponsive to medical therapy. This dissertation deals with the investigation of the effects of the ketogenic diet based on triheptanoin in epileptic seizures in rats and was developed in the form of two articles. The first article, The role of the ketogenic diet on oxidative stress occurring in epilepsy, presents a review of the relationship between oxidative stress and epilepsy, highlighting the possible beneficial effect of ketogenic diet in this context. Several results show that, in fact, this dietary method reduces oxidative stress markers. The second article, entitled Effects of ketogenic diet based on triheptanoin in seizures of rats with epilepsy induced by pilocarpine, describes the experimental study conducted in Wistar rats were divided into three groups, named according to the diet received, in control (standard diet AIN-93G), CetoTAGC7 (ketogenic based in triheptanoin; AIN-93G diet modified to contain 4% soybean oil, 25.79% of triheptanoin and 40% margarine) and CetoTAGsoja (ketogenic based in soybean; AIN-93G diet modified to contain 29.79% of soybean oil margarine and 40%). The ratio lipid: carbohydrate + protein ketogenic diets was 3.5:1 (control diet, 1:11,8) and experimental period lasted 19 days. It was found that the energy value of the share of feed intake and weight gain made by the three groups during the experimental period were not different (P> 0.05). There was no significant difference among the three groups regarding the ratio of feed efficiency (P> 0.05). The behavioral analysis showed no difference for the variable frequency of spontaneous recurrent seizures, however the duration of the attacks of animals belonging to the group triheptanoin was lower in the last experimental day. Future additional research are encouraged, therefore, the results of this study indicate, however modestly, to a potential beneficial effect of triheptanoin to control seizures, which could be investigated under different conditions, like a period longer than is tested by this protocol. / A principal importância da epilepsia do lobo temporal decorre de sua alta prevalência e elevada proporção de pacientes com crises epilépticas refratárias ao tratamento medicamentoso, fazendo-se necessário, neste caso, o uso de terapias alternativas, como a dieta cetogênica. Esta dieta é rica em lipídeos, pobre em carboidratos e proteínas e desde 1921 tem sido utilizada para pacientes não responsivos à terapia medicamentosa. A presente dissertação trata da investigação dos efeitos da dieta cetogênica à base de trienantina nos episódios convulsivos de ratos epilépticos e foi desenvolvida na forma de dois artigos. O primeiro artigo, O papel da dieta cetogênica no estresse oxidativo presente na epilepsia, apresenta uma revisão sobre a relação existente entre o estresse oxidativo e a epilepsia, destacando o possível efeito benéfico da dieta cetogênica neste contexto. Vários resultados atestam que, de fato, esta modalidade dietética diminui os marcadores de estresse oxidativo.O segundo artigo, intitulado Efeitos da dieta cetogênica à base de trienantina nos episódios convulsivos de ratos portadores de epilepsia induzida por pilocarpina, descreve o estudo experimental, realizado em ratos Wistar, subdivididos em três grupos, denominados, segundo a dieta recebida, em Controle (dieta padrão AIN-93G), CetoTAGC7 (cetogênico à base de trienantina; AIN-93G modificada para conter 4% de óleo de soja, 25,79% de trienantina e 40% de margarina) e CetoTAGsoja (cetogênico à base de soja; AIN-93G modificada para conter 29,79% de óleo de soja e 40% de margarina). A proporção lipídeos:carboidratos+proteína das dietas cetogênicas foi de 3,5:1 (dieta controle, 1:11,8) e o período experimental totalizou 19 dias. Verificou-se que o valor energético da cota de ração ingerida e o ganho de peso apresentado pelos três grupos, no período experimental, não foram diferentes (P>0,05). Não houve diferença significativa entre os três grupos, quanto ao coeficiente de eficiência alimentar (P>0,05). As análises comportamentais demonstraram que não houve diferença para a variável frequência de crises recorrentes espontâneas, entretanto a duração das crises dos animais pertencentes ao grupo da trienantina foi menor no último dia experimental. Pesquisas adicionais futuras são encorajadas, pois, os resultados do presente estudo apontam, ainda que modestamente, para um potencial efeito benéfico da trienantina no controle de crises epilépticas, que poderia ser investigado em condições diferentes, a exemplo de um período de tempo superior ao testado pelo presente protocolo de pesquisa.
59

Estudo fitoquímico e biológico dos frutos e raízes de Piper caldense C. DC. (Piperaceae)

Cavalcanti, Élida Batista Vieira Sousa 27 February 2014 (has links)
Submitted by Clebson Anjos (clebson.leandro54@gmail.com) on 2016-03-29T19:16:04Z No. of bitstreams: 1 arquivototal.pdf: 5534324 bytes, checksum: 898113655c311035d0ba3661db9223c8 (MD5) / Made available in DSpace on 2016-03-29T19:16:04Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 5534324 bytes, checksum: 898113655c311035d0ba3661db9223c8 (MD5) Previous issue date: 2014-02-27 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The genus Piper L. is the largest one among the Piperaceae. Containing at least 1000 species, they are located mainly on the neotropical region of Earth and it draws our attention due to its economical, cultural, chemical and medical properties, such as anti-inflamatory, antibacterial and fungicide actions. Species of the genus Piper have been becoming research sources for specific classes of secondary metabolites which play an important role concerning biological activities, including alkaloids, amides, chalcones, chromenes, flavonoids, lignans, cyclopentanediones terpenes, steroids, porphyrin derivatives and benzoic acid derivatives. Piper caldense C. DC., which is commonly known as “Pimenta d’arda”, is used in Paraíba as sedative, snake venom antidote, anti-toothache agent, and as active in located pain treatments through the use of compresses. This research reports the phytochemical study of P. caldense C. DC. fruits and roots. Through usual chromatographic methods and spectroscopic techniques such as IR, MS and one and two-dimensional 1H and 13C NMR techniques and comparison with literature data it was possible to isolate and identify a triglyceride: trilinolein, a mixture of steroids: β-sitosterol and stigmasterol and three benzoic acid derivatives: 4-hydroxy-3- ((2E, 6E, 10E) -3’, 7’, 11’, 15’-tetramethylhexadeca-2’, 6’, 10’, 14’-tetraen-1-yl) benzoic acid, 3,4-dihydroxy-2-((2Z, 6E, 10E) -3’,7’, 11’, 15’-tetramethylhexadeca-2’, 6’, 10’, 14’-tetraen-1-yl) benzoic acid e 4,5-dihydroxy-3-((2E, 6E, 10E)-11-carboxy-3’, 7’, 15’-trimethylhexadeca-2’, 6’, 10’, 14’-tetraen-1-yl) benzoic acid. The last three compounds were subjected to microbiological tests, showing antibacterial activity against Gram negative and Gram positive bacteria of clinical importance. / O gênero Piper L. é o maior da família Piperaceae, compreendendo pelo menos 1000 espécies, que se encontram distribuídas especialmente na região neotropical do globo terrestre e se destaca por suas propriedades econômicas, culturais, químicas e medicinais, como anti-inflamatória, antibacteriana, anestésica e fungicida, dentre outros. Espécies do gênero Piper têm-se tornado fontes de pesquisa de classes específicas de metabólitos secundários com marcantes atividades biológicas, incluindo alcaloides, amidas, chalconas, cromenos, flavonoides, lignanas, terpenos ciclopentanodionas, esteroides, derivados porfirínicos e derivados do ácido benzoico. Piper caldense C. DC., conhecida popularmente como “pimenta d’arda”, é utilizada na Paraíba como sedativa, antídoto para picadas de cobras, para dores de dente, bem como na forma de compressa no local afetado para alívio da dor. Este trabalho reporta o estudo fitoquímico das folhas e frutos de P. caldense C. DC. Utilizando-se métodos cromatográficos usuais e técnicas espectroscópicas de IV, EM e RMN de 1H e 13C uni e bidimensionais e a comparação dos dados com a literatura foi possível isolar e identificar do extrato etanólico bruto dos frutos e raízes de Piper caldense C. DC., um triglicerídeo: trilinoleína, uma mistura de esteroides: β-sitosterol e estigmasterol, e três derivados do ácido benzoico: ácido 4-hidroxi-3-((2E,6E,10E)-3’,7’,11’,15’-tetrametilhexadeca-2’,6’,10’,14’-tetraen-1-il) benzoico, ácido 3,4-dihidroxi-2-((2Z,6E,10E)-3’,7’,11’,15’-tetrametilhexadeca-2’,6’,10’,14’-tetraen-1-il) benzoico e ácido 4,5-dihidroxi-3-((2E,6E,10E)-11-carboxi-3’,7’,15’-trimetilhexadeca-2’,6’,10’,14’-tetraen-1-il) benzoico. As três últimas substâncias isoladas foram submetidas a ensaios microbiológicos, apresentando atividade antibacteriana frente a bactérias Gram negativas e Gram positivas de importância clínica.
60

Odocoileus hemionus (hemionus) on the North Rim of the Grand Canyon: A Study of Wildlife Nutrition, Metabolic Response and Interaction of the Herd with the Winter Habitat on the North Kaibab Plateau.

January 2014 (has links)
abstract: A mule deer herd exists on the northern rim of the Grand Canyon, located on the North Kaibab Plateau. Historical references to this indigenous mule deer herd presented reports of periodic population irruption and collapse. Partially funded by the Arizona Game and Fish Department and the Arizona Deer Association, examination of herd nutritional and metabolic status from the Fall 2005 - Spring 2008 was completed at the request of AzGFD and ADA. Habitat analysis included forage micro-histological, protein, and caloric content plus whole blood and plasma assays gauging herd metabolic response. Modelling was completed using best management practices wildlife energy demand calculations and principal component analysis. Forage quality analysis and modelling suggest a sufficient amount of nitrogen (N) available (DPI) to the deer for protein synthesis. Energy analysis (MEI) of forage suggest caloric deficiencies are widely prevalent on the north Kaibab plateau. Principal component analysis integrates forage and metabolic results providing a linear regression model describing the dynamics of forage utilization, energy availability, and forage nitrogen supply with metabolic demand and response of the mule deer herd. Most of the plasma and blood metabolic indicators suggest baseline values for the North Kaibab mule deer. Albumin values are in agreement with albumin values for mule deer in the Southwest. I suggest that the agreed values become a standard for mule deer in the Southwestern U.S. As excess dietary N is converted to a caloric resource, a continual state of under-nutrition exists for the deer upon entering the N. Kaibab winter range. The population is exceeding the nutritional resource plane that the winter habitat provides. Management recommendations include implementation of multiple small-scale habitat rehabilitation efforts over time, including invasive juniper (Juniperous osteosperma) and piñon (Pinus edulis) management, prescribed burning to control big sage (Artemesia tridentata) populations, and reseeding treated areas with a seed mix of native shrubs, grasses and forbs. I recommended that the population size of the North Kaibab deer herd is maintained at the current size with natural selection controlling growth, or the population be artificially reduced through increased hunting opportunities. / Dissertation/Thesis / Ph.D. Environmental Design and Planning 2014

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