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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.
61

The Lipid Handling Capacity of Subcutaneous Fat Requires mTORC2 during Development

Hsiao, Wen-Yu 30 June 2020 (has links)
Overweight and obesity are associated with Type 2 Diabetes, non-alcoholic fatty liver disease, cardiovascular disease and cancer, but all fat is not equal as storing excess lipid in subcutaneous white adipose tissue (SWAT) is more metabolically favorable than in visceral fat. Here, we uncover a critical role for mTORC2 in setting SWAT lipid handling capacity. We find that subcutaneous white preadipocytes differentiating without the essential mTORC2 subunit Rictorexpress mature adipocyte markers but develop a striking lipid storage defect. In vivo,this results in smaller adipocytes, reduced tissue size, lipid re-distribution to visceral and brown fat, and sex-distinct effects on systemic metabolic fitness. Mechanistically, mTORC2 promotes transcriptional upregulation of select lipid metabolism genes controlled by PPARgand ChREBP. These include genes that control lipid uptake, synthesis, and degradation pathways as well as Akt2, the gene encoding its substrate and insulin effector. Finally, we reveal a potential novel mTORC2 target, ACSS2, which might control intracellular acetyl-CoA availability and regulate metabolic gene expression by altering histone modification in white adipocytes. Exploring this pathway may uncover strategies to promote safe lipid storage and improve insulin sensitivity.
62

Self-Management of Type 1 Diabetes Across Adolescence: A Dissertation

Keough, Lori A. 01 December 2009 (has links)
Little is known about what variables affect self-management practices of adolescents with T1D. Few studies have examined differences in self-management behaviors by stage of adolescence. Similarly, no studies have examined all of the attributes of self-management, including Collaboration with Parents and Goals. In order to fill the gaps in the literature, a secondary data analysis with a descriptive correlation design was conducted to describe T1D self-management behaviors (Collaboration with Parents, Diabetes Care Activities, Diabetes Problem Solving, Diabetes Communication and Goals) during early, middle and late stages of adolescence. This study also examined whether the roles of covariates (regimen, duration of illness (DOI), gender) in self-management behaviors vary by stage of adolescence. Data from 504 subjects aged 13 – 21 years were analyzed and the age variable was transformed into three adolescent stages early (13-14) (n=163), middle (15-16) (n=159) and late (17-21) (n=182). The findings revealed significant differences between adolescent stages on Collaboration with Parents and the Diabetes Problem Solving subscale. The covariate analysis showed no significant effect modification for the covariates and stage on any of the subscales so the results did not differ from the ANOVA model. Covariate analysis showed significant associations between regimen and Collaboration with Parents, Diabetes Care Activities and Diabetes Problem Solving. DOI showed significant associations only with Diabetes Problem solving and gender had significant associations with Diabetes Care Activities and Diabetes Communication. The mean scores on Collaboration with Parents show an incremental decline in collaboration with parents as adolescents move through stages. The higher mean Diabetes Problem Solving scores found in the late adolescent group compared correlated with a higher degree of problem solving in this group when compared to those in the early or middle adolescent stage group. Regimen had significant associations with three of the five subscales suggesting this is an important variable for future study. DOI did not have a significant impact on self-management whereas gender related differences in the areas of Diabetes Activities and Diabetes communication warrant further investigation.
63

The Relationship Between Vitamin D Status of Adult Women and Diet, Sun Exposure, Skin Reflectance, Body Composition, and Insulin Sensitivity

McAdler, Marisa M 01 May 2013 (has links) (PDF)
As the prevalence of vitamin D deficiency continues to grow, mounting evidence supporting its link with chronic disease strengthens suggesting vitamin D’s candidacy in the prevention and treatment of multiple disease states and their complications. Dietary guidelines, however, do not take sun exposure into account. The present study sought to explore the impact of sun exposure on vitamin D status (serum 25(OH)D), and identify other significant determinants of serum levels which may have the greatest effects on overall health. Participants (n = 34) were pre-menopausal women aged 18 to 50 years (mean age 39 ± 6 years), who had their blood drawn at a local pathology lab and a follow-up appointment at a health assessment lab for the collection of other measurements. Mean serum 25(OH)D level was 64 ± 18 nmol/L, and mean dietary vitamin D intake was approximately 327 ± 229 IU/day. Although 82% of participants were below the RDA guidelines (600 IU/day for females ages 9-50 years) for dietary vitamin D intake, only 32% had serum 25(OH)D levels < 50 nmol/L (the recommended level of sufficiency for bone health) reflecting deficiency. While serum 25(OH)D levels were significantly correlated to dietary vitamin D intake (r = 0.42, p = 0.0139), it is reasonable to assume that participants obtained adequate vitamin D from sun exposure. Fasting serum insulin levels were significantly, positively correlated with BMI (r = 0.83, p < 0.0001), and sun exposure index (Body Surface Area x Minutes of Direct Sunlight) was significantly, positively correlated with serum 25(OH)D levels (fall weekend SEI: r = 0.47, p = 0.0059; spring weekend SEI: r = 0.43, p = 0.0135; average weekend SEI: r = 0.43, p = 0.013; and average overall SEI: r = 0.39, p = 0.0247). Reported sun exposure appeared to be least during winter weekdays and the most during summer weekends. Regression analysis was used to determine the strongest predictors of serum 25(OH)D levels, which were found to be sun exposure, dietary vitamin D intake, skin reflectance, age, BMI, and ethnicity (R2 = 0.58 , p = 0.0031), demonstrating that simple questionnaires, such as those employed in this study, can help to predict serum 25(OH)D status and thus be considered in the future treatment of vitamin D deficiency.
64

Comparative Differences Between Traditional Chinese Medicine and Western Medicine in Treating Type Two Diabetes Mellitus

Morales, Neley 01 May 2014 (has links)
In the United States alone, there were 25.8 million people suffering from diabetes in 2010. The prevalence of diabetes is expected to markedly increase worldwide over the next 30 years, an estimated 2.8% in 2000 and 4.4% in 2030. For individuals diagnosed with type 2 diabetes mellitus (T2DM), treatment is essential to control adverse effects such as hypertension and diabetic neuropathy. The focus of this study is to examine various approaches to maintain and improve the lifestyle of individuals suffering from T2DM. A comparative approach has been used to evaluate the differences in the treatment of T2DM with the use of traditional Chinese medicine (TCM) and Western medicine. In Western society, pharmaceuticals are commonly used as a treatment method to manage hyperglycemia, along with life-style modifications. Furthermore, TCM views the human body and its functioning in a holistic way, stating that no single body part or symptom can be understood apart from its relation to a whole. Herbal medications and other treatments in TCM are targeted to treat underlying medical complaints that resulted in symptoms, instead of treating one specific manifestation. Data collection has been gathered through Qualitative over the phone interviews with patients suffering from T2DM, as well as TCM physicians. Interviews were conducted on patients that were diagnosed with T2DM (fasting plasma glucose levels of 126 or greater and HbAlc levels [greater than] 8%), and had continued treatment longer than three months prior to interviews. Collection of chart notes containing glucose levels, levels of pain, lifestyle changes, and vital signs were also used. A total of 21 patients from a family practice were interviewed, answering 23 constructed questions based on treatment of choice (TCM or western) and their personal input on treatment satisfaction. Patients varied in age, ethnicities, and gender, ranging from 39-70 years of age. Two traditional Chinese medicine physicians were also interviewed. Interviews with TCM physicians elaborated on course of treatment and steps taken to diagnose T2DM. Furthermore, prescription medications were also charted and documented to further analyze with secondary data. Upon completing the interviews, the data stated 21 patients (total population questioned) had not experienced alternative medicine and were exposed only to western medicine as treatment. A major concern for most patients were the pharmaceutical side effects, and 85.1% of patients stated they would be interested in an alternative treatment. Due to insufficient sources and knowledge on TCM treatment, 14.2% of patients stated they were satisfied with their western medicine treatment of choice and would not change treatment. The research's objective was to evaluate the differences in treatment of T2DM. Data collected supported the objective and showed the lack of sources to alternative treatments aside from western medicine. The researcher informed and educated interviewees about literature review on traditional Chinese medicine about alternative treatments available to treat T2DM.
65

Identification of the Effects of Diabetes Mellitus on the Brain

Mikhail, Tryphina A 01 January 2016 (has links)
As more studies accumulate on the impact of diabetes mellitus on the central nervous system, they resound with the same conclusion - diabetes has a detrimental effect on cognition regardless of the presence of comorbidities. Less consistent however, are the specific mental processes wherein these declines are noticeable, and the structural changes that accompany these reductions in mental capacity. From global atrophy to changes in the volume of gray and white matter, to conflicting results regarding the effects of hypo- and hyperglycemic states on the development of the hippocampus, the studies display a variety of results. The goal of this research is to link the structural and compositional changes occurring in the diabetic brain with the clinical and behavioral findings highlighted in the literature, as well as to explore the potential mechanisms behind the pathologic brain state of diabetic encephalopathy. Using diabetic (OVE26) and non-diabetic wild type (FVB) mice as models, differences in the number of hippocampal neurons in the dentate gyrus, and cornu ammonis areas 1,2, and 3 were investigated through Nissl staining. Neurodegeneration was confirmed in those cells determined to be hyperchromatic in the diabetic model through staining with Fluoro-Jade C. Finally, the presence of progenitor cells in the hippocampus was compared in the diabetic and non-diabetic models using Musashi-1 antibodies, to determine whether neurogenesis in these areas is affected by diabetes. These experiments were performed to better understand the effect of DM on learning and memory, and could potentially explain the linkage between diabetes mellitus and the increased prevalence of Alzheimer’s disease, vascular dementia, and depression in this subset of the population.
66

Avaliação dos níveis de corte do hormônio estimulador da tireoide na triagem neonatal para a detecção de hipotireoidismo congênito no Estado de Mato Grosso / Thyroid-stimulating hormone evaluation in neonatal screening for the detection of congenital hypothyroidism in the State of Mato Grosso

Silvestrin, Stela Maris 29 April 2014 (has links)
INTRODUÇÃO: O Hipotireoidismo congênito (HC) é uma das endocrinopatias mais frequentes em pediatria e pode causar retardo mental e do crescimento, se não for tratado precocemente. A determinação do nível do hormônio estimulador da tireoide em sangue total após o nascimento (TSHneo) constitui uma estratégia efetiva para o rastreamento de HC, embora não exista consenso em relação aos níveis considerados seguros para essa detecção. Muitos serviços utilizam os valores de corte do TSH neonatal de 10,0 e 15,0 ?UI/mL, por ensaios imunofluorimétricos. OBJETIVO: Analisar a capacidade de detecção dos casos de hipotireoidismo congênito por diferentes níveis de corte do TSH neonatal e os efeitos destes sobre o sistema de triagem neonatal para essa doença, em nascidos vivos avaliados pelo Programa de Triagem Neonatal (PTN) da rede pública do Estado de Mato Grosso (MT), de 01 de janeiro de 2010 a 31 de dezembro de 2012. MÉTODOS: Estudo de coorte, de corte transversal, com coleta retrospectiva de dados obtidos a partir do banco de dados do Serviço de Referência em Triagem Neonatal do Estado de Mato Grosso, de nascidos vivos no período 01/01/2010 a 31/12/2012 e avaliados pelo PTN-MT. Estes foram divididos em dois grupos: I. Controle: Crianças com exame de triagem neonatal normal; II. Estudo: Crianças com HC. Análise estatística incluiu o uso do teste qui-quadrado ou exato de Fischer para análise das características dos recém-nascidos entre os grupos e o teste t de Student ou não paramétrico de Mann-Whitney para análise dos níveis de TSH em sangue total de ambos os grupos e, avaliação das concentrações de TSH e T4 livre no soro, em crianças com HC. Construiu-se uma curva ROC (Receiver Operating Characteristic), para a avaliação dos pontos de corte do TSHneo. O nível de significância foi p<0,05. RESULTADOS: Entre as 111.705 crianças triadas pelo Programa, 50 tiveram o diagnóstico de HC, sob o ponto de corte do TSHneo de 5,0 ?UI/mL. A prevalência da doença foi de 1:2.234 nascidos vivos. A cobertura do Programa estadual foi de 73,9%. Para o Grupo II, os níveis do TSHneo foram superiores a 20,0 ?UI/mL em 61,4% das crianças e, os níveis de TSH no soro excederam este valor em 83,7%. A curva ROC identificou o ponto de corte do TSHneo de 5,03 ?UI/mL, como o correspondente à sensibilidade de 100% e a maior especificidade associada (93,7%). A área observada sob a curva foi de 0,9898 (p<0,0001). CONCLUSÕES: Observou-se uma cobertura inadequada do PTN-MT. O ponto de corte do TSH neonatal de 5,0 ?UI/mL, adotado pelo PTN-MT, foi confirmado pela curva ROC como o mais seguro para detectar HC e determinou a elevada prevalência da doença no Estado de Mato Grosso / INTRODUCTION: Congenital hypothyroidism (CH) is a very common pediatric endocrine disorder and can cause mental and growth retardation without early treatment. Measuring the total blood thyroid-stimulating hormone level after birth (TSHneo) is an effective screening strategy for CH, although there is not yet a consensus on the appropriate diagnostic levels. Many services use the neonatal TSH cut-off points of 10.0 and 15.0 uIU/mL per imunofluorimetric assay. OBJECTIVE: The aim of the present study was to analyze the ability of various TSHneo cutoff values to detect CH and their effects on the Newborn Screening Program (NSP) of the State of Mato Grosso (MT) from January 1, 2010, to december 31, 2012. METHODS: Cohort study, cross-sectional, based on retrospective data collection obtained from the database of the Reference Service for Neonatal Screening of the State of Mato Grosso, for all live births from January 1, 2010, to December 31, 2012, reviewed by NSP-MT. The infants were divided into two groups: I-Control: infants with normal newborn screening tests and II-Study: infants with CH. Statistical analysis included the chi-square or Fisher\'s exact test to compare the characteristics of the newborns from both groups and Student\'s t-test or the non-parametric Mann-Whitney test to analyse the total blood TSH level from both groups of infants and evaluate the serum TSH and free thyroxine (T4) concentrations in infants with CH. A Receiver Operating Characteristic (ROC) curve was constructed to assess the TSHneo cutoff values. The significance level was p < 0.05. RESULTS: Using a TSHneo cutoff value 5.0 uIU/mL, 50 out of 111,705 screened infants were diagnosed with CH. The prevalence of CH was 1:2,234 live births. The state program coverage was 73.9%. For Group II, the TSHneo levels were higher than 20.0 uIU/mL in 61.4% of infants, and the serum TSH levels exceeded that level in 83.7%. The ROC curve showed that a TSHneo cutoff value of 5.03 uIU/mL had 100% sensitivity and the greatest associated specificity (93.7%). The area under the curve was 0.9898 (p < 0.0001). CONCLUSIONS: An inadequate coverage of the NSP-MT was observed. The ROC curve confirmed that the TSHneo cutoff value of 5.0 ?IU/mL adopted by the NSP-MT was the safest for detecting CH and determined the high prevalence of disease that was found in the State of Mato Grosso
67

Avaliação dos níveis de corte do hormônio estimulador da tireoide na triagem neonatal para a detecção de hipotireoidismo congênito no Estado de Mato Grosso / Thyroid-stimulating hormone evaluation in neonatal screening for the detection of congenital hypothyroidism in the State of Mato Grosso

Stela Maris Silvestrin 29 April 2014 (has links)
INTRODUÇÃO: O Hipotireoidismo congênito (HC) é uma das endocrinopatias mais frequentes em pediatria e pode causar retardo mental e do crescimento, se não for tratado precocemente. A determinação do nível do hormônio estimulador da tireoide em sangue total após o nascimento (TSHneo) constitui uma estratégia efetiva para o rastreamento de HC, embora não exista consenso em relação aos níveis considerados seguros para essa detecção. Muitos serviços utilizam os valores de corte do TSH neonatal de 10,0 e 15,0 ?UI/mL, por ensaios imunofluorimétricos. OBJETIVO: Analisar a capacidade de detecção dos casos de hipotireoidismo congênito por diferentes níveis de corte do TSH neonatal e os efeitos destes sobre o sistema de triagem neonatal para essa doença, em nascidos vivos avaliados pelo Programa de Triagem Neonatal (PTN) da rede pública do Estado de Mato Grosso (MT), de 01 de janeiro de 2010 a 31 de dezembro de 2012. MÉTODOS: Estudo de coorte, de corte transversal, com coleta retrospectiva de dados obtidos a partir do banco de dados do Serviço de Referência em Triagem Neonatal do Estado de Mato Grosso, de nascidos vivos no período 01/01/2010 a 31/12/2012 e avaliados pelo PTN-MT. Estes foram divididos em dois grupos: I. Controle: Crianças com exame de triagem neonatal normal; II. Estudo: Crianças com HC. Análise estatística incluiu o uso do teste qui-quadrado ou exato de Fischer para análise das características dos recém-nascidos entre os grupos e o teste t de Student ou não paramétrico de Mann-Whitney para análise dos níveis de TSH em sangue total de ambos os grupos e, avaliação das concentrações de TSH e T4 livre no soro, em crianças com HC. Construiu-se uma curva ROC (Receiver Operating Characteristic), para a avaliação dos pontos de corte do TSHneo. O nível de significância foi p<0,05. RESULTADOS: Entre as 111.705 crianças triadas pelo Programa, 50 tiveram o diagnóstico de HC, sob o ponto de corte do TSHneo de 5,0 ?UI/mL. A prevalência da doença foi de 1:2.234 nascidos vivos. A cobertura do Programa estadual foi de 73,9%. Para o Grupo II, os níveis do TSHneo foram superiores a 20,0 ?UI/mL em 61,4% das crianças e, os níveis de TSH no soro excederam este valor em 83,7%. A curva ROC identificou o ponto de corte do TSHneo de 5,03 ?UI/mL, como o correspondente à sensibilidade de 100% e a maior especificidade associada (93,7%). A área observada sob a curva foi de 0,9898 (p<0,0001). CONCLUSÕES: Observou-se uma cobertura inadequada do PTN-MT. O ponto de corte do TSH neonatal de 5,0 ?UI/mL, adotado pelo PTN-MT, foi confirmado pela curva ROC como o mais seguro para detectar HC e determinou a elevada prevalência da doença no Estado de Mato Grosso / INTRODUCTION: Congenital hypothyroidism (CH) is a very common pediatric endocrine disorder and can cause mental and growth retardation without early treatment. Measuring the total blood thyroid-stimulating hormone level after birth (TSHneo) is an effective screening strategy for CH, although there is not yet a consensus on the appropriate diagnostic levels. Many services use the neonatal TSH cut-off points of 10.0 and 15.0 uIU/mL per imunofluorimetric assay. OBJECTIVE: The aim of the present study was to analyze the ability of various TSHneo cutoff values to detect CH and their effects on the Newborn Screening Program (NSP) of the State of Mato Grosso (MT) from January 1, 2010, to december 31, 2012. METHODS: Cohort study, cross-sectional, based on retrospective data collection obtained from the database of the Reference Service for Neonatal Screening of the State of Mato Grosso, for all live births from January 1, 2010, to December 31, 2012, reviewed by NSP-MT. The infants were divided into two groups: I-Control: infants with normal newborn screening tests and II-Study: infants with CH. Statistical analysis included the chi-square or Fisher\'s exact test to compare the characteristics of the newborns from both groups and Student\'s t-test or the non-parametric Mann-Whitney test to analyse the total blood TSH level from both groups of infants and evaluate the serum TSH and free thyroxine (T4) concentrations in infants with CH. A Receiver Operating Characteristic (ROC) curve was constructed to assess the TSHneo cutoff values. The significance level was p < 0.05. RESULTS: Using a TSHneo cutoff value 5.0 uIU/mL, 50 out of 111,705 screened infants were diagnosed with CH. The prevalence of CH was 1:2,234 live births. The state program coverage was 73.9%. For Group II, the TSHneo levels were higher than 20.0 uIU/mL in 61.4% of infants, and the serum TSH levels exceeded that level in 83.7%. The ROC curve showed that a TSHneo cutoff value of 5.03 uIU/mL had 100% sensitivity and the greatest associated specificity (93.7%). The area under the curve was 0.9898 (p < 0.0001). CONCLUSIONS: An inadequate coverage of the NSP-MT was observed. The ROC curve confirmed that the TSHneo cutoff value of 5.0 ?IU/mL adopted by the NSP-MT was the safest for detecting CH and determined the high prevalence of disease that was found in the State of Mato Grosso
68

Possible endocrine disruption in molluscs from the Limpopo Province / Ignatius Michael Viljoen

Viljoen, Ignatius Michael January 2010 (has links)
With parts of SA in a malaria endemic area, a preventative way of fighting malaria is with the use of pesticides such as 1,1,1–Trichloro–2,2–bis(pclorophenyl) ethane, also known as DDT. DDT is listed under the persistent organic pollutants (POPs) and considered an endocrine disruptive compound (EDC) under the Stockholm Convention. SA registered an exemption to use DDT as means to fight malaria. DDT and its isomers are, however, known EDCs. Combined with their ability to persist in the environment while not being target specific motivates further studies into possible detrimental effects. The present study aimed to establish if ED was present by comparing the male reproductive organs from snails from an area currently sprayed with DDT (for malaria control) to an area not sprayed with DDT in the Limpopo Province. A possible endpoint (the penis sheath/preputium length ratio or PSPLR) was identified for the freshwater snail Bulinus tropicus. B. tropicus and sediment samples were collected from DDT–sprayed and nonsprayed areas located close together. The snails were dissected and various morphometric parameters measured. Sediments from the sites where the snails were collected were analysed for DDT using GC–MS. Statistical analysis showed significant differences in PSPLR (and therefore possible ED) between snails from the two areas. The difference in PSPLR values was mainly due to a relatively shorter preputium for the snails from the DDT–sprayed area. Even though the sediment samples showed that DDT was present in most of the DDT–sprayed sites and not in the non–DDT sprayed sites, causality of the possible ED could not be established from this field study. This study indicated the possibility of using the PSPLR as endpoint for ED. Recommendations are made for further development of the PSPLR and B. tropicus as biological indicators for endocrine disruption, but causality must first be established. / Thesis (M.Sc (Environmental Science))--North-West University, Potchefstroom Campus, 2011.
69

Possible endocrine disruption in molluscs from the Limpopo Province / Ignatius Michael Viljoen

Viljoen, Ignatius Michael January 2010 (has links)
With parts of SA in a malaria endemic area, a preventative way of fighting malaria is with the use of pesticides such as 1,1,1–Trichloro–2,2–bis(pclorophenyl) ethane, also known as DDT. DDT is listed under the persistent organic pollutants (POPs) and considered an endocrine disruptive compound (EDC) under the Stockholm Convention. SA registered an exemption to use DDT as means to fight malaria. DDT and its isomers are, however, known EDCs. Combined with their ability to persist in the environment while not being target specific motivates further studies into possible detrimental effects. The present study aimed to establish if ED was present by comparing the male reproductive organs from snails from an area currently sprayed with DDT (for malaria control) to an area not sprayed with DDT in the Limpopo Province. A possible endpoint (the penis sheath/preputium length ratio or PSPLR) was identified for the freshwater snail Bulinus tropicus. B. tropicus and sediment samples were collected from DDT–sprayed and nonsprayed areas located close together. The snails were dissected and various morphometric parameters measured. Sediments from the sites where the snails were collected were analysed for DDT using GC–MS. Statistical analysis showed significant differences in PSPLR (and therefore possible ED) between snails from the two areas. The difference in PSPLR values was mainly due to a relatively shorter preputium for the snails from the DDT–sprayed area. Even though the sediment samples showed that DDT was present in most of the DDT–sprayed sites and not in the non–DDT sprayed sites, causality of the possible ED could not be established from this field study. This study indicated the possibility of using the PSPLR as endpoint for ED. Recommendations are made for further development of the PSPLR and B. tropicus as biological indicators for endocrine disruption, but causality must first be established. / Thesis (M.Sc (Environmental Science))--North-West University, Potchefstroom Campus, 2011.
70

Gene Expression and Profiling of Human Islet Cell Subtypes: A Master’s Thesis

Blodgett, David M. 25 July 2012 (has links)
Background: The endocrine pancreas contains multiple cell types co-localized into clusters called the Islets of Langerhans. The predominant cell types include alpha and beta cells, which produce glucagon and insulin, respectively. The regulated release of these hormones maintains whole body glucose homeostasis, essential for normal metabolism and to prevent diabetes and complications from the disease. Given the heterogeneous nature of islet composition and absence of unique surface markers, many previous studies have focused on the whole islet. Sorting islet cells by intracellular hormone expression overcomes this limitation and provides pure populations of individual islet cell subsets, specifically alpha and beta cells. This technique provides the framework for characterizing human islet composition and will work towards identifying the genetic changes alpha and beta cells undergo during development, growth, and proliferation. Methods: Human islets obtained from cadaveric donors are dissociated into a single cell suspension, fixed, permeabilized, and labeled with antibodies specific to glucagon, insulin, and somatostatin. Individual alpha, beta, and delta cell populations are simultaneously isolated using fluorescence activated cell sorting. Candidate gene expression and microRNA profiles have been obtained for alpha and beta cell populations using a quantitative nuclease protection assay. Thus far, RNA has been extracted from whole islets and beta cells and subjected to next generation sequencing analysis. Results: The ratio of beta to alpha cells significantly increases with donor age and trends higher in female donors; BMI does not appear to significantly alter the ratio. Further, we have begun to investigate the unique gene expression profiles of alpha and beta cells versus whole islets, and have characterized the microRNA profiles of the two cell subsets. Conclusions: By establishing methods to profile multiple characteristics of alpha and beta cells, we hope to determine how gene, miRNA, and protein expression patterns change under environmental conditions that lead to beta cell failure or promote beta cell development, growth, and proliferation.

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