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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.
81

Avaliação nutricional de pacientes portadores de insuficiência cardíaca no período pré-transplante cardíaco / Nutritional assessment of heart failure patients after listing for cardiac transplantation

Helenice Moreira da Costa 10 September 2008 (has links)
A desnutrição freqüentemente está presente em pacientes com insuficiência cardíaca (IC), podendo trazer aumento de complicações e mortalidade. O objetivo do estudo foi o de avaliar o estado nutricional de pacientes portadores de IC refratária, aguardando a realização de transplante cardíaco. Avaliação nutricional foi realizada utilizando-se da avaliação subjetiva global, avaliação antropométrica completa [índice de massa corpórea (IMC), circunferência do braço (CB), prega cutânea tricipital (PCT), circunferência muscular do braço (CMB) e área gordurosa do braço (AGB)], avaliação laboratorial e realização de anamnese alimentar em dois momentos: no momento de admissão na fila de transplante (1a avaliação) e 4 meses após (2a avaliação). Na 1ª avaliação foram estudados 56 pacientes, idade média de 46±12 anos, 67,8% homens, 33,9% com miocardiopatia chagásica. Análise de dados antropométricos revelou com base no IMC: 73,2% eutróficos e 5,3% com baixo peso; CMB: 66% apresentavam depleção. Houve correlação negativa e significativa entre IMC e fator de necrose tumoral (r= - 0,305; p= 0,022). Análise laboratorial demonstrou: baseado na albumina, 50% dos pacientes apresentavam-se com algum grau de depleção, na transferrina 40% e na contagem de linfócitos 80%. Houve correlação negativa e significativa entre albumina e interleucina-6 (r = - 0,464; p< 0,001), transferrina e interleucina-6 (r= -0,269; p= 0,047) e contagem de linfócitos e interleucina-6 (r= - 0,394; p=0,003). Na 2ª avaliação 18 pacientes foram estudados. Não foram observadas diferenças significativas entre as duas avaliações quanto aos parâmetros estudados. Com base na realização da anamnese alimentar os pacientes atingiram aproximadamente 85% e 84% de suas necessidades calóricas na 1ª e 2ª avaliações, e com relação à ingestão protéica, tanto na 1ª como na 2ª avaliação mais de 70% dos pacientes apresentaram consumo adequado de proteínas. Foi observado consumo abaixo das necessidades nutricionais de cálcio, potássio, magnésio, zinco, folato e vitamina E. Quanto ao sódio verificamos um consumo acima do recomendado. Foram transplantados 14 pacientes com idade de 44 ± 21 anos, 57,1% do sexo masculino, quatro pacientes morreram no pós operatório. Não houve diferenças significativas quanto aos dados antropométricos, laboratoriais, de adequação alimentar e idade entre o grupo de transplantados que sobreviveram (n=9) comparados com os que faleceram (n=4). Concluímos que a desnutrição é comum em pacientes com IC grave aguardando transplante cardíaco. A avaliação nutricional baseada no IMC não mostrou ser um bom método, necessitando ser complementada com as medidas de CB, CMB, PCT e AGB. A avaliação laboratorial permitiu a detecção de comprometimento nutricional. A participação das citocinas inflamatórias no processo de desnutrição foi evidenciada em nossa população. Portanto, a avaliação nutricional completa deve fazer parte do atendimento em pacientes com IC crônica, particularmente aqueles com IC refratária à espera por um transplante cardíaco / Malnutrition is frequently present in patients with heart failure (HF) and is associated with an increase in morbidity and mortality. The objective of this study was to evaluate nutritional status of patients with refractory HF waiting for cardiac transplantation. Nutritional evaluation was done with the use of subjective global assessment, complete anthropometric measurements (body mass index (BMI), mid-arm circumference (MAC), triceps skinfold thickness (TSF), mid-arm muscle circumference (MAMC) and arm fat area), laboratory evaluation and food intake assessment in two moments: at the admission to the cardiac transplantation waiting list (1st evaluation) and after 4 months (2nd evaluation). On the 1st evaluation, we studied 56 patients, mean age 46±12 years, 67.8% were men, and 33.9% had Chagas disease. Analyzing anthropometric measurements, we found that, based on BMI 73.2% of patients were normal and 5.3% had underweight; MAMC revealed 66% with depletion. There was a negative and significant correlation between BMI and tumor necrosis factor-a (r= - 0.305; p<0.022). Laboratory evaluation showed that based on albumin levels, 50% of patients had some degree of depletion, based on transferrin 40% and on lymphocyte count 80%. There were negative and significant correlations between albumin and interleukin-6 (r= - 0.464; p<0.001), transferrin and interleukin-6 (r= -0.269; p<0.047) and lymphocyte count and interleukin-6 (r= -0.394; p<0.003). On the 2nd evaluation 18 patients were studied. There were no significant differences in the studied parameters between the 1st and 2nd evaluations. Based on the food intake assessment, percentage of adequacy of calories intake was 85% and 84% on 1st and 2nd evaluations, and more than 70% of patients had adequate protein intake on both evaluations. Low intake of calcium, potassium, magnesium, zinc, folate and vitamin E was detected. Daily sodium intake was found to be above the recommended levels. Fourteen patients were submitted to cardiac transplantation, mean age 44±21 years, 57.1% were men. Four patients died in post operative period. No relation was observed between anthropometric, laboratory, alimentary adequacy and age variables between patients transplanted that survive (n=9) and that died (n=4). We concluded that malnutrition is common in patients with refractory HF listed for cardiac transplantation. Nutritional assessment based on BMI did not show to be a good index to detect nutritional disorders and need to be used together with MAC, TSF, MAMC and arm fat area. Laboratory evaluation permitted the detection of compromised nutritional status. The participation of inflammatory cytokines in the process of malnutrition was evidenced in our population. Therefore, a complete nutritional evaluation should be part of routine care of patients with chronic HF, particularly in those with refractory HF waiting for cardiac transplantation
82

Perfil lipídico e inflamação sistêmica na caquexia associada ao câncer. / Lipid profile and systemic inflammation in cancer cachexia.

Daniela Mendes dos Reis Riccardi 19 October 2015 (has links)
A caquexia associada ao câncer, cujo o sintoma mais notável é a severa e rápida perda de peso, afeta cerca de 80% dos pacientes com câncer avaçado e constitui causa direta de morte em 22 a 40% dos casos. Estudos recentes têm mostrado que os mediadores inflamatórios têm um papel importante no desenvolvimento de caquexia, hoje em dia considerada como uma doença inflamatória crónica. Um possível contribuinte é o tecido adiposo branco (TAB) que sofre diversas alterações, como por exemplo, reorganização morfológica e aumento da lipólise, liberando assim ácidos graxos livres (AGL), que por sua vez, podem acentuar a produção de citocinas pró-inflamatórias. O objetivo do presente estudo foi analisar a expressão gênica de citocinas pró-inflamatórias no TAB e estabelecer se os ácidos graxos que são liberados pelos adipócitos na vigência da caquexia deflagram e/ou contribuem para inflamação local e sistêmica. O estudo envolveu 122 pacientes divididos em 3 grupos: controle (N), câncer sem caquexia (WSC) e câncer com caquexia (CC). O grupo CC foi composto por pacientes com uma perda de peso não intencional superior a 5% nos últimos 12 meses e atendeu a no mínimo três dos cinco critérios utilizados para a classificação da caquexia e o grupo WSC foi composta por pacientes em tratamento para o câncer, sem declarar a perda de peso> 5% nos últimos 12 meses. O tecido adiposo subcutâneo (TASC) apresentou aumento da expressão gênica de TNF- e uma tendência do aumento para a expressão gênica de CCL-2 no CC comparado ao N, enquanto o conteúdo de RNAm da IL-10 diminuiu no mesmo grupo. Sugerimos que o TASC enconta-se inflamado nos pacientes com caquexia associado ao câncer e um possível ativador da secreção de proteínas pró-inflamatórias nesse tecido poderia ser a maior presença de acidos graxos livres. / The cachexia associated with cancer, whose most notable symptom is severe and rapid weight loss, affecting about 80% of patients with cancer and avacado is the direct cause of death in 22 to 40% of cases. Recent studies have shown that inflammatory mediators play an important role in the development of cachexia, nowadays considered as a chronic inflammatory disease. A possible contributory is white adipose tissue (TAB) that undergoes various changes, such as morphological reorganization and increased lipolysis, thereby releasing free fatty acids (AGL), which in turn, can enhance the production of pro-inflammatory cytokines. The aim of this study was to analyse the gene expression of proinflammatory cytokines in the TAB and establish whether the fatty acids are released by fat cells in the presence of cachexia trigger and / or contribute to local and systemic inflammation. The study involved 122 patients divided into 3 groups: control (N) without cancer cachexia (WSC) and cancer cachexia (CC). The CC group consisted of patients with a loss of unintentional weight more than 5% in the last 12 months and met at least three of the five criteria used for classification of cachexia and the WSC group was composed of patients on treatment for cancer without declaring weight loss> 5% in the last 12 months. The subcutaneous adipose tissue (TASC) showed an increase in TNF- and increase the tendency of gene expression for CCL-2 gene expression in the CC as compared to N, while the mRNA content of IL-10 decreased in the same group. We suggest that the TASC is ignited in patients with cachexia associated with cancer and possible activator of secretion of proinflammatory proteins that fabric could be increased presence of free fatty acids.
83

Avaliação da associação entre o tratamento com metformina e suplementação nutricional com leucina no metabolismo protéico de ratos portadores do tumor de Walker 256 / Effects of metformin treatment associated to leucine rich-diet on protein metabolism in Walker 256 tumour-bearing rats

Oliveira, André Gustavo de, 1980- 19 August 2018 (has links)
Orientador: Maria Cristina Cintra Gomes Marcondes / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-19T11:39:14Z (GMT). No. of bitstreams: 1 Oliveira_AndreGustavode_M.pdf: 2220744 bytes, checksum: ad8fc9b9eb42ef7af7f4733b165e19b0 (MD5) Previous issue date: 2011 / Resumo: O crescimento do câncer promove o desenvolvimento de caquexia em função de intensa espoliação de nutrientes, principalmente, de gordura e proteína corpórea total. A via de sinalização da mTOR controla o crescimento celular e alguns estudos apontam que a inibição dessa via por metformina (M) pode diminuir a taxa de desenvolvimento tumoral. Desse modo, o presente estudo avaliou os efeitos da administração de metformina associada à dieta rica em leucina (L), em animais com tumor de Walker 256 (W), sobre o metabolismo protéico muscular, na hipótese de melhorar o estado caquético. Ratos Wistar jovens foram distribuídos em oito grupos, de acordo com a presença ou não de tumor, tratamento com metformina (36 mg x Kg-1) e/ou dieta rica em leucina (dieta com excesso de 3%). Foram analisados parâmetros somáticos e bioquímicos bem como vias de sinalização celular no músculo gastrocnêmico. No grupo W, o crescimento tumoral induziu perda de 20% da massa corpórea; proporcionou redução de 70% na massa gorda, alem da diminuição da concentração sérica de glicose, de proteínas totais e albumina. As concentrações de GH e IGF-1 foram reduzidas, porém a concentração de ACTH foi elevada em todos os grupos com tumor. Os grupos portadores de tumor tiveram maiores taxas de degradação protéica muscular, embora as taxas de síntese não tenham sido alteradas. A suplementação com leucina estimulou a síntese protéica nos animais não portadores de tumor, e os resultados sugerem que esse efeito tenha sido via Akt ou Erk, enquanto que a metformina estimulou a sinalização via IRS-1, levando à ativação de Erk. A evolução tumoral promoveu espoliação da massa protéica e modulação dos processos de síntese protéica, através da inibição da Erk e IRS-1. A suplementação com leucina foi capaz de estimular a síntese protéica nos animais não portadores de tumor, porém o tratamento com metformina não foi eficaz em diminuir o crescimento das células tumorais, provavelmente em função da baixa concentração que foi administrada aos animais / Abstract: Tumour growth induces cachexia by intense nutrient waste, characterized by involuntary host weight loss, mainly depleting the total body protein and fat. mTOR signaling pathway controls the cell growth regulating translation of mRNA, and the inhibition of this pathway by compounds such as metformin (M) could decrease tumour growth rate. Knowing these facts, the aim of this study was to evaluate metformin effects associated to leucine-rich diet in Walker 256 (W) tumour-bearing animals, on muscle protein metabolism, trying to improve the cachectic state. Young male Wistar rats were distributed into 8 groups, according to the tumour implant, the treatment with metformin (36 mg x kg-1) and/or leucine-rich diet (3% leucine). After the sacrifice of the animals we evaluated some somatic and biochemical parameters as well as the muscle cell signaling pathways.. Tumour growth promotes 20%reduction of body mass and 70% of fat mass. Glucose serum was 50% decreased and also the total serum proteins (20% less) and albumin (25% reduced). GH and IGF-1 concentrations were decreased in all tumour-bearing groups, while ACTH concentration was increased. Tumour-bearing groups had higher protein degradation rates while protein synthesis rates were not changed, showing decreased protein turnover. Leucine rich-diet stimulated protein synthesis in non-tumour-bearing groups and these results suggest that this effect was through Akt or Erk pathways and metformin stimulated signaling through IRS-1, leading to Erk activation. Tumour growth promoted lean body mass spoliation and modulated protein synthesis through Erk and IRS-1 inhibition. Leucine-rich diet was able to stimulate protein synthesis in non tumour-bearing animals, although the treatment with metformina was not thus effective in decreasing tumour's cells growth, probably by low dose concentration / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
84

Avaliação da composição corporal, citocinas inflamatórias e gasto energético basal em pacientes com câncer de cabeça e pescoço antes e após o tratamento padrão / Assessment of body composition, inflammatory cytokines and resting energy expenditure in patients with head and neck cancer before and after treatment standard.

Carvalho, Thalyta Morandi Ridolfi de, 1985- 19 August 2018 (has links)
Orientador: Sarah Monte Alegre / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-19T20:32:32Z (GMT). No. of bitstreams: 1 Carvalho_ThalytaMorandiRidolfide_M.pdf: 1082546 bytes, checksum: 8844f3f5a4c8f2d69eee5b1aa85f8f02 (MD5) Previous issue date: 2012 / Resumo: Mundialmente estimam-se 644.000 novos casos de câncer de cabeça e pescoço no mundo com dois terços dos casos ocorrendo em países em desenvolvimento. Os principais sinais e sintomas clínicos são dificuldade para engolir os alimentos, aumento do volume da região cervical, rouquidão, sangramento e em alguns casos dor que guiam o paciente à perda de peso. O presente estudo teve como objetivo avaliar o gasto energético basal e os fatores que mais influenciam na perda de peso de trinta e dois pacientes com carcinoma de células escamosas de cabeça e pescoço em estádios III e IV do sistema TNM antes e após 30 dias do término da radioterapia e quimioterapia,compreendidos numa faixa etária de 30 a 65 anos, de ambos os sexos. A seleção dos indivíduos foi realizada no ambulatório de Oncologia do Hospital das Clinicas -Universidade Estadual de Campinas. A coleta de dados realizou-se na Unidade Metabólica, 6° andar do HC-UNICAMP que englobou o preenchimento de um questionário com informações pessoais (idade, sexo, tabagismo), avaliação do estado nutricional (peso, altura e avaliação subjetiva global preenchida pelo próprio paciente), avaliação da composição corporal (bioempedância elétrica, circunferência braquial, prega cutânea do tríceps e circunferência muscular do braço), avaliação do gasto energético basal (calorimetria indireta), avaliação metabólica/bioquímica (colesterol total e frações, triglicérides, glicemia, insulinemia, adiponectina, leptina, fator de necrose tumoral (TNF-?), interleucina 1 (IL-1?), interleucina 6 (IL-6) e avaliação da sensibilidade à insulina (HOMA). Além disso os pacientes foram avaliados em relação à ingestão alimentar por meio do recordatório de 24 horas e do Índice de Alimentação Saudável. Os dados foram digitados em banco de dados utilizando-se o programa Excel e para a análise estatística utilizou-se o programa SAS para Windows versão 9.1.3. com nível de significância ? 5%. Nosso estudo mostrou que não podemos justificar a perda de peso pelo aumento do gasto energético basal e/ou diminuição do gasto energético basal, sendo a mesma influenciada por fatores derivados do tumor e pelo início de um processo inflamatório e sugerimos que o aporte nutricional precoce e a ressecção tumoral antes de iniciar o tratamento poderiam melhorar o prognóstico do paciente / Abstract: Worldwide, an estimated 644,000 new cases of head and neck cancer are diagnosed each year, with two- thirds of cases occurring in undeveloped countries. They are usually seen as a set of signs and symptoms which include lesions of the oral cavity, swelling of the neck, difficulty in swallowing food, hoarseness, bleeding and ultimately pain that in some cases can lead to malnutrition. Furthermore, the standard treatment increases weight loss. The main of this study was to evaluate the resting energy expenditure and the factors that had the most influence on weight loss of thirty two patients (aged between 30 and 65 years of both genders) with squamous cell carcinoma of head and neck in stage III and IV of the TNM system before and after 30 days of completion radiotherapy and chemotherapy. The selection of subjects was performed at the Hospital Oncology Clinic, University of Campinas. Data collection took place in the Metabolic Unit which included filling out a questionnaire with personal information such as (age, sex, smoker or non-smoker ...), assessment of nutritional status (weight, height and subjective global assessment completed by the patient), evaluation of body composition (bioelectrical impedance, arm circumference, triceps skinfold and arm muscle circumference), evaluation of resting energy expenditure (indirect calorimetry), evaluation of metabolic / biochemical factors (total cholesterol and fractions , triglycerides, glucose, insulin, adiponectin, leptin, tumor necrosis factor ? (TNF-?), interleukin 1 ? (IL-1?), interleukin 6 (IL-6) and evaluation of insulin sensitivity (HOMA). In addition, the patient was evaluated in relation to food intake by 24-hour recall and the Healthy Eating Index. The data were entered into the database using the program Excel and the statistical analysis used the SAS for Windows version 9.1. 3. with a significance level ? 5%. Our study demonstrated that we cannot justify the weight loss either by increasing the resting energy expenditure or decreasing; it is influenced by factors derived from the tumor and the beginning of an inflammatory process. Nutritional support and early tumor resection before starting treatment improves the nutritional prognosis / Mestrado / Ciencias Basicas / Mestre em Clinica Medica
85

Inflamação e alteração metabólica na caquexia: papel dos adipócitos, do fígado e da modulação oferecida pela microbiota intestinal. / Cancer cachexia inflammation and metabolic: contribution of adipocyte, of the liver and modulation by intestinal microbiota.

Rodrigo Xavier das Neves 10 June 2016 (has links)
Objetivo do estudo foi estudar a participação dos adipócitos e do fígado na inflamação e o papel da microbiota ao longo da progressão da caquexia. Para verificar o comportamento dos adipócitos e do fígado utilizamos ratos Wistar macho de 8 semanas, divididos em dois grupos: i) controle; ii) tumor. Este último foi subdividido em 2 grupos: a) 7º. e b) 14º. dia após a inoculação das células tumorais. Para avaliar o comportamento da microbiota durante o quadro de caquexia utilizamos camundongos C57Bl/6 convencional e germ free de 8-10 semanas, divididos em quatro grupos: i) Convencional controle; ii) Germ Free controle; iii) Convencional tumor; iv) Germ Free tumor. A célula tumoral usada para esse modelo foi Lewis Lung Carcinoma. Adipócitos isolados dos TAB, mesentérico, mais o fígado, mostraram que a via do inflamassoma esta ativa na fase terminal da caquexia. No modelo Germ Free, observamos que a caquexia apresenta-se é acelerada no tecido adiposo epididimal comparado aos camundongos convencionais tumor. Em conclusão, os adipócitos e o fígado desempenha papel importante no estabelecimento da inflamação, enquanto que a simbiose da microbiota parece ser essencial para combater a redução do tecido adiposo. / The goal of this study the role of adipocytes and liver inflammation and the role of microbiota along the progression of cachexia. The main aspects evaluated were increased of the inflammation, alteration in both pathways NF-kB and the inflammasome, and importance of the microbiota during progression of cachexia. To verify the behavior of adipocytes and liver I used Eight weeks-old male rats, I divided into two main groups: i) control; ii) tumor. The latter was divided into 2 groups: a) 7º. and b) 14º. day after tumor cell. To assess the microbial behavior during the development of cachexia I used C57BL/6 conventional mice and Germ Free 8-10 weeks, they were divided into four groups: i) Conventional control; ii) Germ Free control; iii) Conventional tumor; iv) Germ Free tumor. The tumor cell used in this model was Lewis Lung Carcinoma. Adipocytes isolated from TAB, mesenteric further the liver, showed that the inflammasome pathway is active in the terminal phase of cachexia. In model of Germ free mice we observed that cachexia is accelerated in epididymal adipose tissue compared to conventional tumor. In conclusion, adipocytes and liver seem to play a relevant role in the establishment of inflammation, while the microbial symbiosis seems to be essential for combating the reduction of adipose tissue.
86

Development and Characterization of formulations for the nose-to-brain delivery of ghrelin and the management of cachexia

Salade, Laurent 04 October 2019 (has links) (PDF)
For many years, the nasal route of administration as part of a therapeutic treatment has been used. This route of administration is easy to implement, especially due to its non-invasiveness the ease of administration that it affords for the patient. In addition, it is suitable for chronic treatment as well as for an emergency situation when the patient is unconscious. For instance, the administration of benzodiazepines, such as midazolam, may be done to stop convulsions in a patient.Traditionally, intranasal administration was mainly borrowed to target a local effect (e.g. treatment of a cold with a decongestant agent). Subsequently, its application for systemic delivery (e.g. treatment of migraine with triptans) was more and more frequently considered. However, the administration of a drug in the nasal cavities for systemic delivery still remains limited. Indeed, even if the intravenous route has several major limitations such as its invasiveness or the pain generated during administration, it remains more widely used than the intranasal route. This can be explained, on the one hand, by the knowledge that was relatively limited regarding the nasal delivery but also because of the unavailability of nasal devices allowing precise control of the nasal administration (i.e. accurate dose delivery, strong deposition in the nasal cavity, etc).Subsequently, the intranasal route has led to a third therapeutic targeting, namely, the “nose-to-brain pathway”. In that case, the nasal cavity was considered as an opportunity to access the central nervous system (CNS). Indeed, the nose-to-brain delivery allows reaching the brain while bypassing the blood-brain barrier which is known to be a major obstacle to the diffusion of drugs in the CNS. Moreover, the passage through the nasal cavity would allow the administration of sensitive molecules (e.g. biopharmaceuticals) while avoiding excessive enzymatic degradation.Therefore, the nose-to-brain pathway appears to be an attractive route for the delivery of unstable molecules, requiring an access to the brain to reach their site of action. In this context, the therapeutic target that has been selected was "cachexia". It is a complex metabolic syndrome associated with underlying illness and characterized by loss of muscle with or without loss of fat mass. It usually results in particular from undernutrition and a generalized inflammatory state in the patient. In order to treat this syndrome and to restore the appetite in these patients, the goal was to use ghrelin (GHRL) as a model drug. GHRL is a peptide hormone that exhibits, among other effects, an orexigenic action. This biopharmaceutical needs to reach its receptors, located in the hypothalamus, to exert its therapeutic effect.In this study, the goal was to develop a formulation that was able to protect GHRL during its nasal administration, while increasing its residence time to promote its diffusion through the nasal olfactory epithelium.In the first part of the project, GHRL was mainly characterized in terms of stability (e.g. temperature and pH), but also in terms of surface charge. These results allowed selecting the most suitable strategy of formulation as well as the optimal storage conditions. After these preformulation evaluations, it was decided to work on the development of a liquid formulation. The first formulation was based on micelles composed of lipids with polyethylene glycol "DSPE-PEG (1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N- [amino (polyethylene glycol) -2000] (ammonium salt)" as hydrophilic group. This type of pegylated lipids have already shown, in many scientific studies, interesting properties in the context of intranasal administration, especially in terms of mucopenetration. With a slight adaptation of the protocol found in the literature, it was possible to obtain micelles of an adequate size (~15 nm). The micelles produced also showed good ability to encapsulate GHRL with an encapsulation rate of 98%, but micelles of DSPE-PEG failed to increase the GHRL diffusion through epithelial layer. This step is essential in order to obtain high GHRL levels in the brain. The formulation containing DSPE-PEG micelles has thus been abandoned.Still in the goal of combining lipid excipients with hydrophilic polymer, another formulation strategy based on liposomes coated with chitosan has been considered. Since GHRL has a positive charge at physiological pH, anionic liposomes have been developed to get a high loading. Three types of liposomes have been produced: anionic, neutral and cationic. The objective was to evaluate the influence of the liposomes charge on GHRL encapsulation. By working with anionic liposomes, the loading could be 46% higher than that obtained from the cationic liposomes. In order to evaluate a potential relation between the amount of GHRL that was encapsulated in the liposomes and the amount of GHRL that could potentially be degraded in the presence of enzyme, the three types of liposomes were exposed to trypsin. Following enzyme exposure, anionic liposomes showed enzymatic protection 4 times higher than cationic liposomes. These anionic liposomes have also shown high GHRL protection in the presence of another enzyme with another mechanism of digestion, namely, carboxylesterase-1. Subsequently, isothermal titration calorimetry tests were performed to better understand the interaction mechanisms between GHRL and anionic liposomes. This technique showed that hydrophobic interactions between both compounds were predominant. The coating of anionic liposomes by chitosans was performed and confirmed by an increase of the mean diameter (+48 nm) and charge (+6 mV) as well as by the modification of the morphology of the liposomes. This coating of liposomes with chitosans was supposed to confer additional properties to the formulation such as mucoadhesion and permeation enhancement. These both effects can be obtained thanks to the positive charge of chitosans which allows adhering to the mucins of the mucus, on the one hand, and thanks to the opening of the epithelial tight junctions that enhances drug permeation, on the other hand. The chitosan coating allowed increasing the fixation of the liposomes to mucins by about twenty percent compared to uncoated liposomes. In addition, the "absorption promoter" effect of chitosans was confirmed on cells culture. Then, the formulation was introduced into two distinct nasal devices intended for the administration of liquid nasal sprays, namely, the VP3 device from Aptar Pharma and the SP270 device from Nemera. The aerosols produced by each device allowed generating droplets characterized by a mean diameter higher than 10µm, leading to potential satisfactory impaction onto the olfactory region instead of diffusion throughout posterior region of the nasal cavities. In the second part of the work, a dry formulation was produced by spray-drying from the liquid dispersion of coated liposomes. The objective was to increase the stability of GHRL during storage as well as to enhance its remanence and diffusion through the olfactory epithelium. The optimized parameters allowed producing a powder characterized by a mean diameter higher than 10 μm with an acceptable yield. The powder produced exhibited a low residual moisture and showed good homogeneity in terms of GHRL content. Then, a comparative study was carried out between the powder and the liquid formulation to compare the GHRL stability over time during storage at different temperatures (4°C and 25°C) but also their ability to fix mucins. In both cases, the dry powder showed better results The powder was also re-dispersed in aqueous phase to evaluate the ability of the liposomes to be reconstituted without modifying their physicochemical properties (e.g. size distribution, charges, stability). It was demonstrated that the majority of the initial properties could be preserved after reconstitution (i.e. rate of encapsulation). Similarly to the liquid formulation, the powder was loaded into a specific device developed for the nasal administration of powders that allows targeting the olfactory region to optimize the nose-to-brain transfer. The device, "UDS - Unit Dose System " from Aptar Pharma, has shown excellent properties in terms of particle size distribution in the aerosol but also in terms of targeting the olfactory zone. The latest was studied by means of "nasal cast" that is a 3-printed model of artificial nasal cavities. After impaction in the different cavities of the cast, it was possible to quantify the amount of GHRL that was deposited in the olfactory zone. Using our optimized formulation in combination with the device developed by Aptar, it was shown that 52% of the powder was impacted onto the area corresponding to the olfactory region. Such data demonstrated the relative difficulty to target this section of the nasal cavities.Finally, the formulation loaded with fluorescent GHRL was intranasally administered in mice. It was demonstrated that GHRL could reach the brain after intranasal administration of the formulation and that the formulation was essential to allow this transfer to the brain.The administration of such biopharmaceutical by nose-to-brain with this formulation seems to be an interesting alternative to exploit. However, additional studies to quantify this transfer more precisely, to better define its kinetics and also to evaluate the efficacy of the treatment should be carried out. / Doctorat en Sciences biomédicales et pharmaceutiques (Pharmacie) / info:eu-repo/semantics/nonPublished
87

Deep Proteome Profiling in the Progression of Pancreatic Ductal Adenocarcinoma-Associated Cachexia

Umberger, Tara 09 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Cachexia is a devastating muscle wasting syndrome affecting multiple biochemical pathways and is a comorbidity of many diseases including pancreatic ductal adenocarcinoma (PDAC). PDAC patients with cachexia commonly experience systemic inflammation, progressive loss of lean muscle and adipose tissue, and cardiac dysfunction. The present workflow identifies proteins and their post-translational modifications extracted from both cardiac and skeletal muscle tissue isolated from a murine model of PDAC-associated cachexia. Reported here are differentially occurring post-translational modifications found on the most abundant contractile proteins. Tissue from mouse muscle samples were collected two weeks after either receiving a sham surgery or orthotopically implanted with PDAC tumor cells, with or without a follow-up chemotherapy treatment of the standard of care agent gemcitabine with nab-Paclitaxel. Whole tissue blocks of gastrocnemius or heart were either flash frozen and pulverized or homogenized in denaturing lysis buffer and then sonicated to facilitate protein extraction. After disulfide bond reduction, cysteine alkylation, and trypsin digestion, the resultant peptides were subjected to molecular barcoding using tandem mass tag isobaric labeling reagents to facilitate multiplexing. The first and second dimension of peptide separation in the multiplexed sample is accomplished with an offline, high pH, reverse phase (RP)-LC fractionation followed by an online RP-LC at lower pH. The use of high-field asymmetric-waveform ion mobility spectrometry provided a last dimension of separation before MSn analyses. ​This novel, proteomic workflow enables deep proteome profiling in the progression of cancer-induced cachexia. The use of multi-dimensional chromatographic separation and differential ion mobility technique have allowed us to identify almost 4,500 proteins groups of gastrocnemius muscle tissue and nearly 7,100 protein groups of myocardium taken from the murine PDAC model of pancreatic cancer. A comprehensive analysis of the data collected from this workflow was used to calculate differential post-translational modifications on major contractile proteins isolated from PDAC model muscle tissue, with or without chemotherapy, when compared to sham surgery controls. Differential post-translational modifications and protein expression changes found to contribute to cancer cachexia may elucidate novel molecular mechanisms and cellular signaling that drive cachexia progression. / 2022-08-23
88

Exploration of Adipose in the Pathogenesis of Cancer Cachexia

Banh, Taylor January 2018 (has links)
No description available.
89

Intra- and Inter-Rater Reliability in the Cross-Sectional Area of Feline Epaxial Musculature on CT Scan

Rayhel, Laura H. 07 October 2020 (has links)
No description available.
90

The Regulation of Skeletal Myogenesis by C/EBPβ: Lessons from Small Muscles and Big Tumours

AlSudais, Hamood 22 June 2021 (has links)
Skeletal muscle associated disorders are correlated with significant morbidity, including frailty, fatigue, reduced mobility and poor resistance to treatments as well as mental health repercussions resulting from a loss of independence. Thus, conditions affecting skeletal muscle put considerable pressure on the health care system. In response to injury, skeletal muscle can regenerate and the molecular mechanisms underlying this unique process has been the subject of intense research with the goal of developing better treatment modalities for muscle-related diseases. Our laboratory has previously demonstrated that C/EBPβ is a negative regulator of postnatal myogenic differentiation. Expressed in muscle satellite cells (MuSCs), the primary source of regenerative potential in skeletal muscle, C/EBPβ inhibits entry into the myogenic differentiation program and is required for MuSC self-renewal after injury. Despite the important role of C/EBPβ in muscle homeostasis, little is known about the genes it regulates. To better understand how C/EBPβ regulates these processes, I used both a candidate-based approach to identify the inhibitor of DNA binding and differentiation protein ID3 as a C/EBPβ target gene that mediates inhibition of myogenic differentiation, and an unbiased approach using RNA-seq. I compared gene expression profiles from C2C12 myoblasts overexpressing C/EBPβ to control cells under growth and differentiation conditions. I observed that more than 20% of the molecular signature found in quiescent MuSCs is regulated by C/EBPβ. Caveolin- 1 was implicated as a direct target of C/EBPβ and part of the molecular mechanism by which C/EBPβ maintains MuSCs quiescence. Interestingly, the RNA-seq data identified numerous C/EBPβ-regulated secreted proteins including growth factors and cytokines. Co-culture experiments indicate that secreted proteins mediate the inhibition of cell differentiation and fusion, suggesting that C/EBPβ functions in an autocrine and paracrine fashion to influence activation of myoblasts in the absence of cell-to-cell contact. Given the role of C/EBPβ in regulating secretory proteins that inhibit myogenic differentiation, I examined the requirement of C/EBPβ in the expression of anti myogenic proteins secreted by cancer cells that affect MuSCs function and drive the development of cancer cachexia. Indeed, the expression of C/EBPβ in cancer cells was found to be required for the production of a cachexia-inducing secretome by tumours in vitro and in vivo. Furthermore, C/EBPβ was found to be sufficient to convert non-cachectic tumours into cachexia-inducing ones. In comparing differentially expressed C/EBPβ-regulated secreted protein transcripts from our RNA-seq data to that from 27 different types of human cancers revealed an ~18% similarity between C/EBPβ-regulated secreted proteins and those enriched in cachectic tumours including pancreatic, gastric and brain cancers. Three of these C/EBPβ-regulated secreted proteins (SERPINF1, TNFRSF11B and CD93) were tested further and found to be inducers of muscle atrophy. This work provides molecular insight into the role of C/EBPβ in the regulation of MuSC function and the regulation of cachexia-inducing factors by tumours, placing C/EBPβ as a novel therapeutic target for the treatment of cancer cachexia and other muscle-related diseases.

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