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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.
141

Efeitos na expansão volêmica e na oxigenação sistêmica e gastrointestinal após reposição com hidroxietilamido, associado ou não à solução salina hipertônica, e Ringer lactato em cães submetidos a choque hemorrágico /

Barros, João Maximiano Pierin de. January 2009 (has links)
Orientador: José Reinaldo Cerqueira Braz / Banca: Luiz Antonio Vane / Banca: Jorge João Abrão / Banca: Luiz Marcelo Sá Malbonisson / Banca: Rosa Inês Costa Pereira / Resumo: As variáveis hemodinâmicas e de oxigenação sistêmica não refletem com precisão a hipoperfusão esplâncnica durante o choque hipovolêmico, dificultando o tratamento adequado. A expansão volêmica após a reposição fluídica é fundamental para promover a oxigenação sistêmica e regional após o choque hemorrágico. Em contraste com as soluções convencionais de reposição volêmica, a menor expansão plasmática proporcionada pela administração de hidroxietilamido em solução hipertônica de cloreto de sódio, durante o choque hemorrágico, poderia determinar uma menor oferta de oxigênio sistêmico, com prejuízo à oxigenação gástrica. O estudo teve como objetivo comparar a expansão volêmica e os efeitos imediatos na oxigenação sistêmica e da mucosa gástrica após a administração de hidroxietilamido a 6% (peso molecular de 130 kDa, grau de substituição de 0,4) em solução hipertônica de cloreto de sódio a 7,5% (HHEA), Ringer lactato (RL) e hidroxietilamido a 6% (130/0,4) em cloreto de sódio a 0,9% (HEA), em cães submetidos à choque hemorrágico. Trinta cães, sem raça definida, sob anestesia e esplenectomizados, foram submetidos a sangramento (30 ml/kg) visando manter a pressão arterial média de 40 a 50 mm Hg durante 45 9 Introdução e Literatura minutos, sendo feita a reposição volêmica após este período com RL (n=10), na razão de 3:1 para o sangue removido; HEA (n=10), na razão de 1:1 para o sangue removido; e HHEA (n=10), 4 ml/kg. A expansão do volume intravascular (através da diluição do azul de Evans e da hemoglobina), e os atributos hemodinâmicos, e de oxigenação sistêmica e gástrica (através da tonometria gástrica), foram determinados no momento basal, após 45 minutos de hemorragia, e aos 5, 45 e 90 minutos após a reposição volêmica. A solução de HHEA aumentou o volume sanguíneo, devido à alta eficiência na... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Hemodynamic and global oxygen transport variables have failed to reflect splanchnic hypoperfusion, resulting in a failure to recognize inadequately treated hemorrhagic shock. Volemic expansion after fluid resuscitation is essential to improve global and regional oxygen in hemorrhagic shock. We hypothesized that, in contrast with conventional plasma expanders, the smaller volemic expansion from hypertonic hydroxyethyl starch solution administration in hemorrhagic shock may determine lesser systemic oxygen delivery and gastric oxygenation. We used hemorrhaged dogs to compare the early intravascular volume expansion and systemic and gastric oxygenation effects of 7.5% NaCl 6% hydroxyethyl starch 130/0.4 (HHES), lactated Ringer's (LR), and 0.9% NaCl 6% hydroxyethyl starch (HES) solutions. Thirty mongrel dogs anesthetized and submitted to splenectomy, were bled (30mL/kg) to hold mean arterial pressure at 40-50 mm Hg over 45 minutes and were randomly resuscitated in three groups: LR (n=10) at 3:1 ratio to shed blood; HES (n=10) at 1:1 to shed blood; and HHES (n=10), 4mL/kg. Intravascular volume expansion (Evans blue and hemoglobin dilution), hemodynamic, systemic oxygenation and gastric intramucosal- arterial PCO2 gradient (PCO2 gap) variables were measured at baseline, after 45 min of hemorrhage, and 5, 45, and 90 min after fluid resuscitation. HHES increased blood volume, due to the 11 Introdução e Literatura high volume expansion efficiency, but intravascular volume expansion with this solution was the smallest of the solutions. All three solutions induced a similar hemodynamic performance but HHES showed lower mixed venous oxygen saturation and higher systemic oxygenation extraction and PCO2 gap than LR and HES. In conclusion, the smaller volume state from HHES after resuscitation provides worse systemic and gastric oxygenation recovery compared to LR and HES in dogs submitted... (Complete abstract click electronic access below) / Doutor
142

Personers erfarenheter av dagligt liv efter en Gastric ByPass-operation : En narrativ analys av bloggar / Persons' experiences of everyday life after a Gastric ByPass surgery : A narrative analysis of blogs

Westher, Elina, Wester, Victoria January 2017 (has links)
Bakgrund: Fetma är ett hot mot folkhälsan och har ökat snabbt de senaste årtiondena. I Sverige utförs många operationer mot fetma vilket kan minska sjukdomsföljder samt ge en förbättrad livskvalitet. Det finns olika typer av överviktskirurgi där gastric bypassoperationen är den vanligaste. Hälsa är sammankopplat med självuppfattning vilket är av betydelse för de personer som väljer att genomgå en operation. Egenvård används för att bibehålla hälsa i det dagliga livet. Syfte: Syftet med denna studie var att beskriva personers erfarenheter av dagligt liv efter en gastric bypassoperation. Metod: Den metod som användes var narrativ analys av sex bloggar skrivna av kvinnor. Resultat: Ur analysen av datamaterialet framträdde tre kategorier; anpassa till en ny vardag, svårigheter att leva ett normalt liv och medaktör i den fortsatta planeringen med sju underkategorier. Slutsats: Studiens resultat har genererat information som med fördel kan användas för att förstå hur personer som genomgått en gastric bypassoperation erfar det dagliga livet. Denna kunskap kan hjälpa sjuksköterskor till att få en djupare förståelse för dessa personer, kunna tillämpa patientcentrerad vård och därmed bedriva en god omvårdnad. / Background: Obesity is a threat against public health and has grown rapidly the last decades. Many surgeries against obesity are done in Sweden which may reduce disease outcomes as well as providing an improved quality of life. There are different types of obesity surgery where gastric bypass is the most common. Health is connected to self-perception which is important for those who choose to undergo surgery. Self-treatment are used to maintain health in daily life. Objective: The aim of this study was to describe people´s experiences of everyday life after a gastric bypass surgery. Method: The method used was a narrative analysis of six blogs written by women. Result: Three categories emerged from the analysis; adjust to a new daily life, difficulties to live a normal life and co-actors in the continued planning with seven subcategories. Conclusion: The study’s results have generated information that can be advantageously used to understand how people who have undergone a gastric bypass surgery experiencing daily life. This knowledge can help nurses to get a deeper understanding of these people, be able to apply patient-centered care and therefore operate good care.
143

Gastric bypasskirugi : patientupplevelser ur psykosocialt och krppsligt perspektiv / Gastric bypass surgery : patient experinces of psychosocial and physical perspective

Karlsson, Anne-Marie, Nilsson, Maria January 2013 (has links)
Fetma är ett av de allvarligaste hälsoproblemen i världen. Övervikt i såväl ungdomen och vuxenlivet är associerad med en ökad dödlighet. Bestående viktminskning minskar risken att dö i förtid. Gastric Bypass är en kirurgi som hjälper personer med fetma till viktminskning och ger ett minskat näringsupptag. Syftet var att belysa personers psykosociala och kroppsliga upplevelser efter en gastric bypass operation. Arbetet är utformat som en litteraturstudie och baseras på tio kritiskt granskade kvalitativa och kvantitativa artiklar, efter genomläsning och analys tydliggjordes fyra kategorier. I resultatet identifierades fyra huvudteman efter genomgången gastric bypass kirurgi. Det som beskrivs är: känslomässiga förändringar, kontroll över födointag, livskvalité vid kroppsförändringar samt upplevelser i olika relationer. Slutsatsen visar att den upplevda livskvalitén förbättrades eller var god även om undantag sågs. / Obesity is one of the most serious health problems in the world. Obesity in both adolescence and adulthood is associated with increased mortality. Permanent weight loss reduces the risk of dying prematurely. Gastric bypass is a surgery that helps obese people to lose weight and provides a reduced nutrient intake. The aim was to highlight people's psychosocial and physical sensations after gastric bypass surgery. The work is designed as a literature review and based on ten critically examined qualitative and quantitative articles. Analysis of the literature identified four major themes resulting from the completion of gastric bypass surgery. These can be described as: emotional changes, control of food intake, quality of life resulting from body changes and experiences in different relationships. The conclusion shows that the perceived quality of life was improved or was good, although there were exceptions.
144

Depression Screening for Bariatric Surgical Patients

Stidham, Cova Teresa 01 January 2019 (has links)
Obesity in the United States has increased to epidemic numbers over the last decade. Practitioners need to reverse the trend. To address the problem of depression in obesity, a practice guideline from a bariatric clinic for under-served populations was proposed to an expert panel. The Spell Out on First Use (PHQ-9) screening is a valid and reliable self-screening tool to assist the practitioner in determining the level of depression if any. The PHQ-9 has nine questions. No formal screening existed at the bariatric clinic, and the practice guideline (with algorithm and revised workflow) was proposed for use at the clinic. The expert panel consisted of the medical director, a surgeon, a psychiatrist, and a nurse practitioner at the clinic. The expert panel reviewed the materials and made one recommendation: to implement the PHQ-9 upon intake when the patient is being admitted to the program, and the panel recommends administering PHQ-9 prior to assessment by practitioners All panel members were in agreement about full implementation of the practice guideline, provided that an educational program on the revised workflow in the clinic was first presented. The expert panel also reviewed and approved the algorithm and the treatment pathways identified for patients to use in the practice after the results of the PHQ-9 are compiled. It is expected that use of the depression screening tool and recommended guidelines in the bariatric clinic will result in more effective treatment for the patients and thus better outcomes-a significant positive social change.
145

Personers upplevelse av psykisk ohälsa efter en gastric bypassoperation : en litteraturöversikt / Peoples’ experience of mental illness after undergoing gastric bypass surgery : A litterature review

Jarl, Hanna, Omlin, Elin January 2016 (has links)
Bakgrund: Fetma har blivit en folksjukdom med dramatisk ökning och omkring en halv miljon svenskar har idag fetma (BMI>30). I takt med att fetman ökar sker även en ökning av överviktskirurgi där gastric bypass står för 95 % av operationerna. Det har tidigare genomförts studier med fokus på medicinska och fysiologiska effekter efter en gastric bypassoperation. Dessa studier har påvisat framförallt de positiva fysiologiska och medicinska effekterna efter en sådan operation. Däremot har personers upplevelser av en eventuell psykisk ohälsa efter en gastric bypassoperation inte studerats i samma omfattning. Syfte: Belysa hur personer som genomgått en gastric bypassoperation beskriver sin upplevda psykiska ohälsa efter operationen Metod: Litteraturöversikt baserad på tio vetenskapliga artiklar med kvalitativ ansats. Resultat: I studien framkom fyra huvudkategorier som svarade till syftet: ”Upplevelse av tomhet – en saknad av mat”, ”Upplevelse av misslyckande”, ”En negativ självbild och ett ifrågasättande av den nya kroppen” samt ”Upplevelse av smärta och sårbarhet inför omgivningens reaktioner”. Slutsats: Studiens resultat visade på att upplevelser av psykisk ohälsa förekom efter gastric bypassoperation. Studien belyser ett tidigare ganska outforskat område och bidrar med ökad kunskap och förståelse för målgruppen. Resultatet är av vikt för omvårdnadssituationer och för att öka kompetensen hos omvårdnadspersonal kring psykisk ohälsa efter en gastric bypassoperation.
146

Signaling Pathways Coupled to Melatonin Receptor MT1 in Gastric Smooth Muscle

Ahmed, Rashad 21 May 2010 (has links)
The Melatonin, a close derivative of serotonin, is involved in physiological regulation of circadian rhythms. In the gastrointestinal (GI) system, melatonin exhibits endocrine, paracrine and autocrine actions and is implicated in the regulation of GI motility. Generally, melatonin actions oppose the stimulatory actions of serotonin on motility. However, it is not known whether melatonin can also act directly on GI smooth muscle cells. The aim of the present study was to determine the expression of melatonin receptors in smooth muscle and identify their signaling pathways. Muscle cells were isolated from rabbit distal stomach by enzymatic digestion, filtration and centrifugation and cultured in DMEM-10. Expression of melatonin receptors, MT1 and MT2, was determined by RT-PCR and Western blot. G protein activity was measured by melatonin-induced increase in Gα binding to [35S]GTPγS. Phosphoinositide (PI)-specific phospholipase C (PLC-) activity was measured by ion-exchange chromatography. Cytosolic Ca2+ was measured in fura-2 loaded cells and muscle contraction was measured by scanning micrometry. In cultured gastric smooth muscle cells MT1 was detected by RT-PCR and western blot. Melatonin activated Gαq, but not Gαs, Gαi1, Gαi2, or Gαi3. Consistent with activation of Gαq, melatonin stimulated PLC-β activity (PI hydrolysis), increased cytosolic Ca2+, and elicited muscle contraction. Stimulation of PLC-β activity was blocked by the expression of Gq minigene and contraction was blocked by the PLC-β inhibitor, U73122. We conclude that gastric smooth muscle cells express receptors for melatonin (MT1) coupled to Gq. The receptors mediate stimulation of PLC- activity and increase in cytosolic Ca2+, and elicit muscle contraction.
147

Langzeiteffektivität acht Jahre nach Gastric banding-Operation / Long-term effectiveness eight years after gastric banding operation

Ullmann, Birgit January 2007 (has links) (PDF)
Bei morbider Adipositas (BMI > 40 kg/m²), von der in Deutschland 1,6% der übergewichtigen Frauen und 0,5% der übergewichtigen Männer (BMI > 25 kg/m²) betroffen sind, erweisen sich für eine ausreichende und dauerhafte Gewichtsreduktion nur chirurgische Maßnahmen, wie z.B. laparoskopisches Gastric banding als effektiv. Allerdings fehlen Studien zur langfristigen Effektivität. In der vorliegenden Katamnesestudie zur Langzeiteffektivität von Gastric banding acht Jahre nach stattgefundener Operation wurden Veränderungen in Gewicht, depressiver Symptomatik, Selbstakzeptanz, Essverhalten und aufgetretene Komplikationen untersucht. / In Germany 1.6% of overweight women and 0.5% of overweight men (BMI > 25 kg/m²) are morbidly obese. A sufficient and lasting weight loss in patients suffering from morbid obesity (BMI > 40 kg/m²) can only be achieved by surgical intervention such as laparoscopic gastric banding. Long-term results of laparoscopic gastric banding have been rarely reported. In the present follow-up history the long-term effectiveness eight years after gastric banding operation was evaluated: we investigated changes in weight loss, depression, self-acceptance, eating behaviour and complications.
148

Morfologia do esqueleto gástrico em Lithodidae Samouelle, 1819 (Crustacea: Decapoda:Anomura): implicações filogenéticas / Morphology of gastric mill in Lithodidae Samouelle, 1819 (Crustacea: Decapoda: Anomura): Phylogenetic approach

Campillay, Nicole Alice Olguín 25 August 2016 (has links)
Os caranguejos anomuros da família Lithodidae são exclusivamente marinhos, habitantes predominantemente de águas frias vivendo, geralmente, em águas profundas. Via de regra são animais de grande tamanho, sendo que das 124 espécies atualmente conhecidas (distribuídas em 10 gêneros), algumas são de grande importância comercial. O monofiletismo da família Lithodidae e dos gêneros que a compõe, assim como as relações filogenéticas em Lithodidae ainda são obscuros e têm recebido muito pouca atenção. Diante da complexidade do esqueleto gástrico nos crustáceos Decapoda, neste trabalho nós investigamos em detalhe as características morfológicas dos ossículos do esqueleto gástrico em Lithodidae com vistas a sua descrição, interpretação e como fonte de dados morfológicos para servir de base a uma análise filogenética de Lithodidae, cujo objetivo precípuo foi testar a hipótese de monofiletismo de Lithodidae e acessar as relações internas na família. A partir do estudo de 185 estômagos foi descrita e ilustrada a morfologia dos ossículos do esqueleto gástrico de 66 espécies: 52 espécies (dos 10 gêneros de Lithodidae), 8 espécies (dos 5 gêneros de Hapalogastridae) e 6 espécies de outros Decapoda representantes do grupo externo (Birgus latro, Petrochirus diogenes, Pagurus bernhardus, Homarus americanus, Nephrops norvegicus e Thalassina anomala). A análise cladística de Lithodoidea foi realizada no programa TNT. Foram utilizados 126 caracteres binários e 63 caracteres multiestado obtidos da morfologia do esqueleto gástrico, relacionados com o tamanho, forma, grau de calcificação, grau de fusão de ossículos e morfologia dos dentes gástricos. O esqueleto gástrico em Lithodoidea está composto por 44 ossículos. Um novo ossículo foi reconhecido, o parapterocardíaco, associado com o ossículo pterocardíaco. A maioria dos ossículos exibem um padrão uniforme com variações menores e elementos morfológicos característicos. Nossa análise cladística resultou em 10 árvores igualmente parcimoniosas com 1802 passos. Nosso estudo mostra que a superfamília Lithodoidea é monofilética, porém o monofiletismo de Lithodidae e Hapalogastridae não pode ser recuperado. Os gêneros de Lithodidae, Cryptolithodes e Lopholithodes são monofiléticos, enquanto que Lithodes, Neolithodes, e Paralomis são polifiléticos. Paralithodes é parafilético. Os gêneros monoespecíficos de Lithodidae (Glyptolithodes, Phyllolithodes, Rhinolithodes e Sculptolithodes) são bem caracterizados por autapomorfias. Em consequência de nossos resultados, alterações na classificação interna de Lithodoidea são necessárias, afim de refletir as relações evolutivas. / The king crabs of the family Lithodidae (Anomura) are all marine and inhabit predominantly cold, deep waters. The lithodids currently comprise 124 species, some of which attain large sizes and are of great commercial importance. The interrelationships of the lithodids and even their monophyly and some of the constituent genera are yet to be solved. The great complexity of the decapod gastric mill prompted us to study the morphology of the gastric ossicles in the Lithodidae as a source of characters to assess its phylogenetic interrelationships and its monophyletic status as well as that of its constituent genera. We described and illustrated herein the morphology of the gastric ossicles from 66 species. A total of 186 stomachs were obtained as follows: 52 lithodid species (from all the 10 genera currently included in the Lithodidae), 8 hapalocarcinid species (from all the 5 genera of the Hapalogastridae) and 6 species from other groups of decapods representing the outgroup (Birgus latro, Petrochirus diogenes, Pagurus bernhardus, Homarus americanus, Nephrops novegicus e Thalassina anomala). The cladistic analysis of the Lithodoidea, was performed using the program TNT. 126 binary and 63 multistate characters from the morphology of the gastric ossicles related to size, shape, degree of calcification and fusion between ossicles, were used. The stomach of the Lithodoidea consists of 44 ossicles. A new ossicle is recognized herein, the para-pterocardiac, associated with pterocardiac ossicle. Most of the ossicles are conservative in shape, with few variations and distinctive morphological elements. The cladistic analysis resulted in 10 equally parsimonious trees with 1802 steps. Our study show that the superfamily Lithodoidea is monophyletic, whereas the lithodids and hapalogastrids were not recovered as monophyletic groups. The lithodid genera Cryptolithodes and Lopholithodes was recovered as monophyletic, while Lithodes, Neolithodes and Paralomis are polyphyletic; Paralithodes is paraphyletic. The monospecific lithodid genera are well characterized by a number of autoapomorphies each. As a result, the internal classification of the Lithodoidea requires further elaboration in order to reflect evolutionary relationships.
149

Avaliação cintilográfica do esvaziamento gástrico e do trânsito intestinal após cirurgia bariátrica / Scintigraphic evaluation of gastric emptying and of intestinal transit after bariatric surgery

Xavier, Marcia Arruda Fajardo 31 October 2013 (has links)
O presente estudo teve como objetivo avaliar o esvaziamento gástrico e o trânsito intestinal em 31 pacientes (sendo 10 controle e 21 com vômitos) após cirurgia bariátrica de DGYR e a relação das alterações destas duas variáveis entre si e com quadro sintomático e ainda tentar definir o tempo de esvaziamento gástrico desejável. O esvaziamento gástrico e o trânsito gastrintestinal foram avaliados mediante cintilografia, segundo técnicas padronizadas e previamente empregadas em outros estudos. A análise das imagens obtidas e armazenadas foi feita mediante o delineamento de regiões de interesse (ROI, da expressão, em Lingua Inglesa, region of interest) correspondendo ao coto gástrico, para a quantificação do esvaziamento gástrico, e para este segmento e também para as porções proximal e distal do intestino delgado e para a região ileocecal, para o trânsito gastrintestinal. A mesma região de interesse foi utilizada para as contagens de todas as imagens consecutivas, para a mesma projeção e para o mesmo paciente. Para a determinação do esvaziamento gástrico, a atividade em cada momento do estudo foi expressa pela média geométrica das contagens das imagens anteriores e posteriores, para correção do efeito da eventual movimentação intragástrica das partículas do radiotraçador (30, 60, 90 e 120 minutos após ingerir a refeição). Foi feita também correção adicional das contagens para compensar o declínio físico do 99m Tecnécio. Ambas as correções foram feitas automaticamente pelo equipamento. As contagens corrigidas permitiram a construção, para cada sujeito do estudo, da correspondente curva de esvaziamento gástrico, expressa como porcentuais de retenção intragástrica do radiotraçador ingerido, em cada um dos momentos de aquisição das imagens. Foi considerado como tempo inicial o momento em que se deu o término da ingestão da refeição contendo o radioisótopo, que corresponderia idealmente a um estado caracterizado por retenção intragástrica alimentar de todo o ingerido (100%). Após a realização da cintilografia, as imagens permaneceram armazenadas num sistema computadorizado acoplado à gama câmara e, no momento da análise, foram então definidas manualmente as ROI correspondentes ao estômago, ao jejuno, ao íleo e à região ileocecal. Em todos os casos, atentou-se para que as áreas destas ROI fossem semelhantes, o que foi feito levando-se em conta o número de pixels englobado por cada uma das regiões. Foi feita uma subdivisão do grupo com sintomas em 2 subgrupos: 8 pacientes com quadro de vômitos e exames de imagem alterados (EDA e seriografia) e 11 pacientes com quadro de vômitos e exames de imagem normais.O teste de Mann-Whitney bicaudal foi utilizado para comparações entre os dois grupos e entre os dois subgrupos. Os resultados foram apresentados como mediana e percentis, com significância de p < 0,05. Para a verificação das correlações entre esvaziamento gástrico e trânsito intestinal foi utilizado o coeficiente de correlação de Spearman, com significância de p < 0,05: não houve diferença significativa entre os dois grupos nos diversos tempos estudados (30, 60, 90 e 120 minutos) com relação ao esvaziamento gástrico. Também não houve diferença significativa com relação ao trânsito intestinal de acordo com o centro geométrico nos tempos 0, 30, 60, 90 e 120 minutos. Entretanto, houve diferença significativa entre os dois subgrupos extraídos do grupo com sintomas em todos os tempos do esvaziamento gástrico e nos tempos 0, 30, 60 e 90 minutos do trânsito intestinal (centro geométrico). Não houve diferença significativa entre os subgrupos no tempo 120 e na progressão do centro geométrico. Descritores: esvaziamento gástrico, trânsito intestinal, DGYR. / The objective of the present study was to assess gastric emptying and intestinal transit in 31 patients (10 controls and 21 with vomiting as a symptom) after bariatric surgery by RYGB and the relation of the alterations of these two variables between them and with the signs and symptoms, and also to try to define the desirable time of gastric emptying. Gastric emptying and gastrointestinal transit were evaluated by scintigraphy according to standardized techniques previously employed in other studies. The images obtained and stored were analyzed by delineating the regions of interest (ROI) corresponding to the gastric stump for the quantitation of gastric emptying and also for the proximal and distal portions of the small bowel and for the ileocecal region, for the gastrointestinal transit. The same ROI was used to count all the consecutive images for the same projection and for the same patient. For the determination of gastric emptying, the activity at each time point in the study was expressed as the geometric mean of the counts of the anterior and posterior images, for the correction of the effect of eventual intragastric movement of the radiotracer particles (30, 60, 90 and 120 minutes after meal ingestion). The counts were also additionally corrected to compensate for the physical decline of 99m Technetium. Both corrections were automatically made by the equipment. The corrected counts permitted the construction for each subject of the corresponding gastric emptying curve, expressed as percentage of intragastric retention of the ingested radiotracer at each time of image acquisition. The initial time was considered to be the moment when the ingestion of the meal containing the radioisotope occurred, which would ideally correspond to a state characterized by intragastric retention of all the food ingested (100%). After scintigraphy, the images were stored in a computerized system coupled to the gamma camera and, at the time of analysis, the ROI corresponding to the stomach, jejunum, ileum and ileocecal region were defined manually. In all cases, an attempt was made for these ROI to be similar, by taking into account the number of pixels included in each region. The group with symptoms was divided into 2 subgroups: 8 patients with vomiting and altered imaging exams (UDE and seriography) and 11 patients with vomiting and normal imaging exams. The two-tailed Mann-Whitney test was used to compare the two groups and the two subgroups. Data are reported as median and interquartile range, with significance set at p < 0.05. The Spearman correlation coefficient was used to determine the correlations between gastric emptying and intestinal transit, with significance set at p < 0.05. There was no significant difference between the two groups at the various time points studied (30, 60, 90 and 120 minutes) regarding gastric emptying. Also, there was no significant difference regarding intestinal transit according to the geometric center at 0, 30, 60, 90 and 120 minutes. However, there was a significant difference between the two subgroups extracted from the group with symptoms at all times of gastric emptying and at times 0, 30, 60 and 90 minutes of intestinal transit (geometric center). There was no significant difference between subgroups at 120 minutes or in the progression of the geometric center.
150

The role of glucose-dependent insulinotropic peptide in adipocyte. / CUHK electronic theses & dissertations collection

January 2012 (has links)
糖尿病是一种呈现流行趋势的代谢紊乱综合症,现如今,全球大约有3.46亿糖尿病患者, 这庞大的数字给各国的公共健康安全支出带来了严重的财政负担。 其中,二型糖尿病(T2DM)占90%。其特点是周围组织的胰岛素抵抗以及后期损伤的胰岛β细胞的功能。在饮食后,小肠会分泌两种肠促胰岛素,葡萄糖依赖性促胰岛素多肽(GIP)和胰高血糖素样肽-1(GLP-1)。两种多肽的主要功能是促进餐后胰岛细胞中胰岛素的分泌,另外他们还可以通过其自身的G蛋白偶联受体,GIPR和GLP-1R发挥其他作用,如葡萄糖依赖性的刺激胰岛素的生成,刺激胰岛β细胞的增殖,抑制细胞的凋亡等。这些功能也使肠促胰岛素成为糖尿病治疗的一种手段,比如Exendin-4和DPP4抑制剂。 然而,除了在胰岛中的作用,肠促胰岛还可能和脂质代谢相关,其中GIP和脂质代谢的报导研究的更加深入。在肥胖的状态下,血液中GIP含量高于正常水平;GIPR基因敲除老鼠和GIPR的抑制剂喂养的小鼠可以抵抗高脂饮食诱导的肥胖和2型糖尿病;GIP还可以直接调节脂肪细胞的脂肪生成和脂解。这些数据表明GIP在肥胖和糖尿病的发生过程中可能存在促进作用,这使得GIP治疗药物的开发需要谨慎的对待。 / 为了进一步研究GIP在脂肪细胞中发挥的生物学效应,在本研究中,我们利用腺病毒介导技术通过在脂肪细胞中过表达GIPR来增加GIP的活性,然后检查GIP在脂肪细胞中所起的作用。实验结果表明,GIP可以通过cAMP-PKA信号通路迅速并且长期的刺激脂肪细胞的炎症反应,增强IKKβ-NFκB信号通路和增加炎症基因的表达。更深入的机制研究表明,JNK 信号通路也参与GIP诱导的炎症反应,抑制JNK通路可以大部分恢复GIP增加的炎症因子的表达和IKKβ的磷酸化水平。由于长期的炎症反应,脂肪细胞的胰岛素信号通路受到GIP的损伤,在GIPR过表达的脂肪细胞中,胰岛素刺激的AKT磷酸化水平和葡萄糖吸收能力都被GIP降低,葡萄糖转运蛋白4(Glut-4)的表达水平也同时减少。因此,本研究结果表明GIP可能在肥胖的发展过程中,通过诱导脂肪细胞的炎症反应来损伤胰岛素敏感性而最终导致2型糖尿病的发生。 / Diabetes mellitus is a type of metabolic syndrome that has prevailed all over the world with the development of economic and over-nutrient lifestyle. It is estimated to 346 million diabetes patients in the worldwide most recently. The huge population put a major burden on the cost of public health care to all the countries. Among the types of diabetes, type 2 diabetes (T2DM) makes up 90% of recorded cases. The characteristics of T2DM are insulin resistance of peripheral tissues and impaired pancreatic cell function and mass. Two major incretins GIP (glucose-dependent insulinotropic peptide) and GLP-1 (glucagon-like peptide 1) are secreted from gut in response to food ingestion. The prominent role of GIP and GLP-1 is to stimulate glucose-dependent insulin release in pancreatic β cell. In addition, they both exert multiple biological effects via their relative G-protein coupled receptors, GIPR and GLP-1R, including glucose-stimulated insulin production, cell proliferation and anti-apoptosis in pancreatic β cells. The beneficent effects of incretins potentiate them as targets for the treatment of diabetes. GLP-1 analog, exendin-4 and DDP4 (dipeptidyl peptidase-4) inhibitors (to prevent GIP and GLP-1 from degradation) have been already used in clinical research. However, in addition to their effects on pancreatic β cell, both peptides are also related to lipid metabolism. The role of GIP has been studied more extensively. In obese state, the circulating level of GIP is elevated. GIPR knockout (KO) mice are resistant to high fat diet (HFD) induced obesity, a similar phenotype is found in GIPR antagonist administrated HFD-mice. Moreover, GIP also directly promotes lipogenesis and lipolysis in adipocytes. The rising evidence suggests a potential role of GIP in adipocyte biology and lipid metabolism, which diminishes the enthusiasm of GIP as a candidate therapeutic reagent for T2DM. / In order to further understand the biological effects of GIP in adipocytes, here, we over-expressed GIPR in 3T3-L1 CAR adipocytes via adenovirus-mediated gene transfer technology to enhance the activity of GIP. The results demonstrate that GIP impairs the physiological functions of adipocytes as a consequence of increasing the production of inflammatory cytokines, chemokines, and phosphorylation of IkB kinase (IKK) β through activation of the cyclic AMP-protein kinase A (cAMP-PKA) pathway. Activation of Jun N-terminal Kinase (JNK) pathway is also observed in GIP-induced inflammatory responses in adipocytes. An inhibitor of JNK blocks GIP-stimulated secretion of inflammatory cytokines and chemokines, as well as phosphorylation of IKKβ. The chronic inflammatory response eventually impairs insulin signaling in adipocytes, as demonstrated by reduction of protein kinase B (PKB/AKT) phosphorylation. The subsequently physiological analysis also indicates that GIP inhibits insulin-stimulated glucose uptake, and gene expression analysis reveals a decrease of glucose transporter 4 (Glut-4) in the meanwhile. The results suggest that GIP may be one of stimuli attributable to obesity induced insulin resistance via induction of adipocyte inflammation. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Nie, Yaohui. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 95-111). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract --- p.i / 摘要 --- p.iii / Acknowledgements --- p.v / INTRODUCTION --- p.1 / Chapter Part 1 --- Obesity and Type 2 diabetes --- p.1 / Chapter 1.1 --- Introduction to diabetes --- p.1 / Chapter 1.1.2 --- Physiology of adipocyte --- p.4 / Chapter 1.1.3 --- Mechanism of obesity induced diabetes --- p.10 / Chapter Part 2 --- Incretins and T2DM --- p.12 / Chapter 2.1 --- History of incretins --- p.12 / Chapter 2.2 --- Physiological actions of incretins --- p.14 / Chapter 2.3 --- Molecular mechanism of incretin actions in pancreas --- p.16 / Chapter 2.4 --- Incretins and T2DM --- p.19 / Chapter Part 3 --- Incretins and lipid metabolism --- p.23 / Objective --- p.26 / Methods and materials --- p.28 / Chapter 1 --- Cell culture --- p.28 / Chapter 1.1 --- 3T3-L1 culture and differentiation --- p.28 / Chapter 1.2 --- 3T3-L1 CAR culture and differentiation --- p.29 / Chapter 2 --- Cloning and recombinant adenovirus construction --- p.30 / Chapter 2.1 --- Plasmid construct --- p.30 / Chapter 2.2 --- Construct of recombinant adenoviruses --- p.30 / Chapter 2.3 --- Generation and infection of the adenoviruses --- p.31 / Chapter 3 --- Physiological and morphological assays --- p.32 / Chapter 3.1 --- Lipolysis assay --- p.32 / Chapter 3.2 --- TUNEL assay --- p.32 / Chapter 3.3 --- Glucose uptake --- p.33 / Chapter 3.4 --- Glut-4 localization --- p.33 / Chapter 4 --- Gene expression analysis --- p.35 / Chapter 4.1 --- Quantitative real-time PCR --- p.35 / Chapter 4.2 --- Immunoblot analysis --- p.35 / Chapter 4.3 --- ELISA assay --- p.36 / Chapter 5 --- Isolation of primary adipocytes --- p.37 / Results --- p.38 / Chapter Part 1 --- Role of GIP in 3T3-L1 cells --- p.38 / Chapter 1.1 --- Differentiation of 3T3-L1 adipocytes --- p.38 / Chapter 1.2 --- GIP slightly stimulates phosphorylation of p-CREB and lipolysis in 3T3-L1 cells. --- p.40 / Chapter 1.3 --- Analysis of gene expression in GIP-treated adipocytes --- p.42 / Chapter 1.4 --- Discussion --- p.44 / Chapter Part 2 --- Role of GIP in GIPR over-expressing 3T3-L1 CAR adipocytes --- p.46 / Chapter 2.1 --- Differentiation of 3T3-L1 CAR adipocytes --- p.46 / Chapter 2.2 --- Functional tests in GIPR over-expressing 3T3-L1 CAR adipocytes. --- p.48 / Chapter 2.3 --- Effect of GIP on cell viability --- p.50 / Chapter 2.4 --- Analysis of gene expression in GIP-treated adipocytes --- p.52 / Chapter 2.5 --- GIP activates inflammatory responses in GIPR over-expressing adipocytes --- p.54 / Chapter 2.6 --- Inhibition of IKKb pathway restores GIP-induced inflammatory responses --- p.56 / Chapter 2.7 --- Effects of GIP on adipocytes are partially dependent on the cAMP-PKA pathway --- p.58 / Chapter 2.8 --- Activation of cAMP-PKA pathway induces adipocyte inflammation. --- p.60 / Chapter 2.9 --- cAMP-Epac pathway is not involved in GIP-induced inflammation --- p.62 / Chapter 2.10 --- GIP stimulates cell stress activated kinases --- p.64 / Chapter 2.11 --- JNK partially mediates GIP-induced adipocyte inflammation --- p.65 / Chapter 2.12 --- Inhibition of JNK pathway partially restores GIP-induced inflammatory responses --- p.67 / Chapter 2.13 --- GIP impairs insulin signaling in GIPR over-expressing 3T3-L1 CAR adipocytes via inducing inflammatory response --- p.69 / Chapter 2.14 --- GIP enhances basal glucose uptake but impairs insulin stimulated glucose uptake in 3T3-L1 CAR GIPR over-expressing adipocytes --- p.71 / Chapter 2.15 --- Discussion --- p.73 / Chapter Part 3 --- Role of GIP in primary adipocytes --- p.78 / Chapter 3.1 --- GIPR expression level in primary adipocytes --- p.78 / Chapter 3.2 --- Analysis of gene expression in primary adipocytes after GIP treatment --- p.80 / Chapter 3.3 --- Discussion --- p.81 / SUMMARY --- p.82 / Chapter Future investigation --- p.83 / Chapter Appendix 1: --- Abbreviations --- p.86 / Chapter Appendix 2: --- Protocols --- p.90 / Preparation of competent cells --- p.90 / Outlines of recombinant adenovirus preparation --- p.91 / Virus titering (TCID50) --- p.92 / Primers for real-time PCR --- p.93 / Chapter Publications and Scientfic activities --- p.94 / Thesis related publication: --- p.94 / Other pubiliations: --- p.94 / Scientific activities: --- p.94 / References --- p.95

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