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1.
Innov High Educ ; 46(4): 461-479, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33897099

RESUMO

Current policies and interventions to enhance student success and retention are often tied to full-time enrollment, which are substantiated by studies associating part-time enrollment with lower retention and poorer academic outcomes. However, these findings are limited to studies of first-time college students and do not represent today's nontraditional undergraduate who may be transfer, online, and working adult students. To enhance retention of on-campus and hybrid online 2 + 2 transfer students in a STEM undergraduate program, need-based scholarships are awarded to students enrolled full-time as stipulated by the federal granting agency. Although the scholarship has helped >80 students to date, over 40% of eligible transfer students are excluded only because they are enrolled part-time, disproportionately affecting students in the hybrid online track who are more likely to be women and underrepresented minorities. Using quantitative and qualitative methods, this study explores enrollment behavior of transfer students (online and on-campus), its relationship with student characteristics and academic outcomes, and implications for scholarship eligibility. Full-time enrollment is a significant challenge for transfer students. While scholarship requirements are a key factor influencing full-time enrollment, online transfer students additionally cite work and family obligations as drivers of enrollment behavior. Thus, online 2 + 2 transfer students face different challenges than on-campus peers and are more likely to enroll part-time out of necessity, yet still have comparable GPA and graduation rates. These findings support a growing awareness of barriers nontraditional students face questioning the relevance of policies driven by "traditional" student outcomes, which perpetuate inequity in higher education. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s10755-021-09549-7.

2.
J Immunol ; 186(6): 3538-46, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21317395

RESUMO

Although it is known that resident gut flora contribute to immune system function and homeostasis, their role in the progression of the autoimmune disease type 1 diabetes (T1D) is poorly understood. Comparison of stool samples isolated from Bio-Breeding rats, a classic model of T1D, shows that distinct bacterial populations reside in spontaneous Bio-Breeding diabetes-prone (BBDP) and Bio-Breeding diabetes-resistant animals. We have previously shown that the oral transfer of Lactobacillus johnsonii strain N6.2 (LjN6.2) from Bio-Breeding diabetes-resistant to BBDP rodents conferred T1D resistance to BBDP rodents, whereas Lactobacillus reuteri strain TD1 did not. In this study, we show that diabetes resistance in LjN6.2-fed BBDP rodents was correlated to a Th17 cell bias within the mesenteric lymph nodes. The Th17 bias was not observed in the non-gut-draining axillary lymph nodes, suggesting that the Th17 bias was because of immune system interactions with LjN6.2 within the mesenteric lymph node. LjN6.2 interactions with the immune system were observed in the spleens of diabetes-resistant, LjN6.2-fed BBDP rats, as they also possessed a Th17 bias in comparison with control or Lactobacillus reuteri strain TD1-fed rats. Using C57BL/6 mouse in vitro assays, we show that LjN6.2 directly mediated enhanced Th17 differentiation of lymphocytes in the presence of TCR stimulation, which required APCs. Finally, we show that footpad vaccination of NOD mice with LjN6.2-pulsed dendritic cells was sufficient to mediate a Th17 bias in vivo. Together, these data suggest an interesting paradigm whereby T1D induction can be circumvented by gut flora-mediated Th17 differentiation.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/microbiologia , Interleucina-17/biossíntese , Lactobacillus/imunologia , Células Th17/imunologia , Células Th17/microbiologia , Animais , Diferenciação Celular/imunologia , Células Cultivadas , Diabetes Mellitus Tipo 1/patologia , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Limosilactobacillus reuteri/imunologia , Linfonodos/imunologia , Linfonodos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Ratos , Ratos Endogâmicos BB , Células Th17/patologia
3.
Bol Soc Mat Mex ; 19(2): 255-266, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25221355

RESUMO

We show two examples of how we answer biological questions by converting them into statistical hypothesis testing problems. We consider gene abundance data, and apply permutation tests. Though these tests are simple, they allow us to test biologically relevant hypotheses. Here we present the analysis of data rising from two studies on Type 1 Diabetes. In the first study [3] are interested in comparing the gut bacterial biodiversity in children at risk and not at risk of developing diabetes. In the second study, [4] compare the gut bacterial biodiversity of children in six different sites in USA and Europe. The statistical analyses presented here are parts of the "statistical methods" in two papers mentioned above. Here we offer a detailed explanation of the "Statistical Methods" addressed to readers with a statistics background.

4.
Genome Biol ; 22(1): 39, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33478573

RESUMO

BACKGROUND: The Environmental Determinants of Diabetes in the Young (TEDDY) is a prospective birth cohort designed to study type 1 diabetes (T1D) by following children with high genetic risk. An integrative multi-omics approach was used to evaluate islet autoimmunity etiology, identify disease biomarkers, and understand progression over time. RESULTS: We identify a multi-omics signature that was predictive of islet autoimmunity (IA) as early as 1 year before seroconversion. At this time, abnormalities in lipid metabolism, decreased capacity for nutrient absorption, and intracellular ROS accumulation are detected in children progressing towards IA. Additionally, extracellular matrix remodeling, inflammation, cytotoxicity, angiogenesis, and increased activity of antigen-presenting cells are observed, which may contribute to beta cell destruction. Our results indicate that altered molecular homeostasis is present in IA-developing children months before the actual detection of islet autoantibodies, which opens an interesting window of opportunity for therapeutic intervention. CONCLUSIONS: The approach employed herein for assessment of the TEDDY cohort showcases the utilization of multi-omics data for the modeling of complex, multifactorial diseases, like T1D.


Assuntos
Autoimunidade/imunologia , Diabetes Mellitus Tipo 1/imunologia , Inflamação/imunologia , Metabolismo dos Lipídeos/genética , Espécies Reativas de Oxigênio/metabolismo , Autoanticorpos/genética , Autoanticorpos/imunologia , Autoimunidade/genética , Biomarcadores , Estudos de Casos e Controles , Quimiocinas/genética , Estudos de Coortes , Citocinas/genética , Diabetes Mellitus Tipo 1/genética , Progressão da Doença , Feminino , Expressão Gênica , Predisposição Genética para Doença , Humanos , Inflamação/genética , Masculino , Metabolômica , Estudos Prospectivos , Fatores de Risco
5.
Artigo em Inglês | MEDLINE | ID: mdl-31768212

RESUMO

The Microbiology and Cell Science program at the University of Florida compressed two standard 16-week lab courses into five-day versions of the course, which are referred to as bootcamp labs. The bootcamp labs have the same objectives, activities, and assessments as their traditional counterparts. Development of the bootcamp labs was part of a larger effort to increase access to the major, and more broadly STEM, by offering a 2+2 hybrid online transfer program. The results of this mixed-methods study include a direct comparison between bootcamp and traditional lab format as an approach for delivery of a face-to-face lab course. The bootcamp lab cohort has a greater diversity of students, with more women and underrepresented minorities in STEM than the traditional semester-long cohorts. Students in the bootcamp labs have comparable grade outcomes and learning gains to students in traditional lab format. Regression analysis identified GPA, but not lab format, as the most significant predictor of success for students enrolled in lab courses. Qualitative results suggest that the bootcamp format may be a better way than traditional formats to teach microbiology lab. In summary, the results demonstrate that a bootcamp version of a face-to-face microbiology course is just as effective as the traditional semester-long version. This work has broader implications as it supports the bootcamp lab approach as a model in STEM education for increasing access and for overcoming a major barrier to online STEM programs: face-to-face delivery of key lab courses.

6.
CBE Life Sci Educ ; 15(3)2016.
Artigo em Inglês | MEDLINE | ID: mdl-27587859

RESUMO

The Microbiology and Cell Science (MCS) Department at the University of Florida (UF) developed a new model of a 2 + 2 program that uses a hybrid online approach to bring its science, technology, engineering, and mathematics (STEM) curriculum to students. In this paradigm, 2-year graduates transfer as online students into the Distance Education in MCS (DE MCS) bachelor of science program. The program has broadened access to STEM with a steadily increasing enrollment that does not draw students away from existing on-campus programs. Notably, half of the DE MCS students are from underrepresented minority (URM) backgrounds and two-thirds are women, which represents a greater level of diversity than the corresponding on-campus cohort and the entire university. Additionally, the DE MCS cohort has comparable retention and academic performance compared with the on-campus transfer cohort. Of those who have earned a BS through the DE MCS program, 71% are women and 61% are URM. Overall, these data demonstrate that the hybrid online approach is successful in increasing diversity and provides another viable route in the myriad of STEM pathways. As the first of its kind in a STEM field, the DE MCS program serves as a model for programs seeking to broaden their reach.


Assuntos
Engenharia/educação , Internet , Matemática/educação , Grupos Minoritários/educação , Ciência/educação , Tecnologia/educação , Mulheres , Currículo , Avaliação Educacional , Feminino , Humanos
7.
Microbiome ; 4: 17, 2016 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-27114075

RESUMO

BACKGROUND: The development of anti-islet cell autoimmunity precedes clinical type 1 diabetes and occurs very early in life. During this early period, dietary factors strongly impact on the composition of the gut microbiome. At the same time, the gut microbiome plays a central role in the development of the infant immune system. A functional model of the association between diet, microbial communities, and the development of anti-islet cell autoimmunity can provide important new insights regarding the role of the gut microbiome in the pathogenesis of type 1 diabetes. RESULTS: A novel approach was developed to enable the analysis of the microbiome on an aggregation level between a single microbial taxon and classical ecological measures analyzing the whole microbial population. Microbial co-occurrence networks were estimated at age 6 months to identify candidates for functional microbial communities prior to islet autoantibody development. Stratification of children based on these communities revealed functional associations between diet, gut microbiome, and islet autoantibody development. Two communities were strongly associated with breast-feeding and solid food introduction, respectively. The third community revealed a subgroup of children that was dominated by Bacteroides abundances compared to two subgroups with low Bacteroides and increased Akkermansia abundances. The Bacteroides-dominated subgroup was characterized by early introduction of non-milk diet, increased risk for early autoantibody development, and by lower abundances of genes for the production of butyrate via co-fermentation of acetate. By combining our results with information from the literature, we provide a refined functional hypothesis for a protective role of butyrate in the pathogenesis of type 1 diabetes. CONCLUSIONS: Based on functional traits of microbial communities estimated from co-occurrence networks, we provide evidence that alterations in the composition of mucin degrading bacteria associate with early development of anti-islet cell autoimmunity. We hypothesize that lower levels of Bacteroides in favor of increased levels of Akkermansia lead to a competitive advantage of acetogens compared to sulfate reducing bacteria, resulting in increased butyrate production via co-fermentation of acetate. This hypothesis suggests that butyrate has a protective effect on the development of anti-islet cell autoantibodies.


Assuntos
Bacteroides/metabolismo , Ácido Butírico/metabolismo , Diabetes Mellitus Tipo 1/microbiologia , Microbioma Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Verrucomicrobia/metabolismo , Ácido Acético/imunologia , Ácido Acético/metabolismo , Adulto , Autoanticorpos/biossíntese , Autoimunidade , Bacteroides/imunologia , Aleitamento Materno , Ácido Butírico/imunologia , Criança , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Dieta , Feminino , Fermentação , Trato Gastrointestinal/imunologia , Humanos , Imunidade Inata , Lactente , Ilhotas Pancreáticas/imunologia , Masculino , Verrucomicrobia/imunologia
8.
PLoS One ; 10(4): e0119548, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25875606

RESUMO

Although initial interest in science, technology, engineering and mathematics (STEM) is high, recruitment and retention remains a challenge, and some populations are disproportionately underrepresented in STEM fields. To address these challenges, the Microbiology and Cell Science Department in the College of Agricultural and Life Sciences at the University of Florida has developed an innovative 2+2 degree program. Typical 2+2 programs begin with a student earning an associate's degree at a local community college and then transferring to a 4-year institution to complete a bachelor's degree. However, many universities in the United States, particularly land-grant universities, are located in rural regions that are distantly located from their respective states' highly populated urban centers. This geographical and cultural distance could be an impediment to recruiting otherwise highly qualified and diverse students. Here, a new model of a 2+2 program is described that uses distance education as the vehicle to bring a research-intensive university's life sciences curriculum to students rather than the oft-tried model of a university attempting to recruit underrepresented minority students to its location. In this paradigm, community college graduates transfer into the Microbiology and Cell Science program as distance education students to complete their Bachelor of Science degree. The distance education students' experiences are similar to the on-campus students' experiences in that both groups of students take the same department courses taught by the same instructors, take required laboratory courses in a face-to-face format, take only proctored exams, and have the same availability to instructors. Data suggests that a hybrid online transfer program may be a viable approach to increasing STEM participation (as defined by enrollment) and diversity. This approach is particularly compelling as the distance education cohort has comparable grade point averages and retention rates compared to the corresponding on-campus transfer cohort.


Assuntos
Educação a Distância , Universidades , Currículo , Engenharia/educação , Florida , Humanos , Matemática/educação , Ciência/educação , Tecnologia/educação
9.
Diabetes Care ; 38(2): 329-32, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25519450

RESUMO

OBJECTIVE: Gut microbiome dysbiosis is associated with numerous diseases, including type 1 diabetes. This pilot study determines how geographical location affects the microbiome of infants at high risk for type 1 diabetes in a population of homogenous HLA class II genotypes. RESEARCH DESIGN AND METHODS: High-throughput 16S rRNA sequencing was performed on stool samples collected from 90 high-risk, nonautoimmune infants participating in The Environmental Determinants of Diabetes in the Young (TEDDY) study in the U.S., Germany, Sweden, and Finland. RESULTS: Study site-specific patterns of gut colonization share characteristics across continents. Finland and Colorado have a significantly lower bacterial diversity, while Sweden and Washington state are dominated by Bifidobacterium in early life. Bacterial community diversity over time is significantly different by geographical location. CONCLUSIONS: The microbiome of high-risk infants is associated with geographical location. Future studies aiming to identify the microbiome disease phenotype need to carefully consider the geographical origin of subjects.


Assuntos
Diabetes Mellitus Tipo 1/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Intestinos/microbiologia , Microbiota/fisiologia , Pré-Escolar , Diabetes Mellitus Tipo 1/epidemiologia , Fezes/microbiologia , Feminino , Finlândia/epidemiologia , Alemanha/epidemiologia , Humanos , Lactente , Masculino , Projetos Piloto , RNA Ribossômico 16S/metabolismo , Características de Residência , Fatores de Risco , Suécia/epidemiologia , Estados Unidos/epidemiologia
10.
Genome Announc ; 2(3)2014 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-24812223

RESUMO

We report here the complete genome sequences of Lactobacillus johnsonii strain N6.2, a homofermentative lactic acid intestinal bacterium, and Lactobacillus reuteri strain TD1, a heterofermentative lactic acid intestinal bacterium, both isolated from a type 1 diabetes-resistant rat model.

11.
Front Microbiol ; 5: 361, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25101067

RESUMO

Despite the large interest in the human microbiome in recent years, there are no reports of bacterial DNA methylation in the microbiome. Here metagenomic sequencing using the Pacific Biosciences platform allowed for rapid identification of bacterial GATC methylation status of a bacterial species in human stool samples. For this work, two stool samples were chosen that were dominated by a single species, Bacteroides dorei. Based on 16S rRNA analysis, this species represented over 45% of the bacteria present in these two samples. The B. dorei genome sequence from these samples was determined and the GATC methylation sites mapped. The Bacteroides dorei genome from one subject lacked any GATC methylation and lacked the DNA adenine methyltransferase genes. In contrast, B. dorei from another subject contained 20,551 methylated GATC sites. Of the 4970 open reading frames identified in the GATC methylated B. dorei genome, 3184 genes were methylated as well as 1735 GATC methylations in intergenic regions. These results suggest that DNA methylation patterns are important to consider in multi-omic analyses of microbiome samples seeking to discover the diversity of bacterial functions and may differ between disease states.

12.
Diabetes ; 63(6): 2006-14, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24608442

RESUMO

The gut microbiome is suggested to play a role in the pathogenesis of autoimmune disorders such as type 1 diabetes. Evidence of anti-islet cell autoimmunity in type 1 diabetes appears in the first years of life; however, little is known regarding the establishment of the gut microbiome in early infancy. Here, we sought to determine whether differences were present in early composition of the gut microbiome in children in whom anti-islet cell autoimmunity developed. We investigated the microbiome of 298 stool samples prospectively taken up to age 3 years from 22 case children in whom anti-islet cell autoantibodies developed, and 22 matched control children who remained islet cell autoantibody-negative in follow-up. The microbiome changed markedly during the first year of life, and was further affected by breast-feeding, food introduction, and birth delivery mode. No differences between anti-islet cell autoantibody-positive and -negative children were found in bacterial diversity, microbial composition, or single-genus abundances. However, substantial alterations in microbial interaction networks were observed at age 0.5 and 2 years in the children in whom anti-islet cell autoantibodies developed. The findings underscore a role of the microbiome in the pathogenesis of anti-islet cell autoimmunity and type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Fezes/microbiologia , Trato Gastrointestinal/imunologia , Ilhotas Pancreáticas/imunologia , Microbiota/imunologia , Leite Humano/imunologia , Autoimunidade , Aleitamento Materno , Estudos de Casos e Controles , Pré-Escolar , Parto Obstétrico/efeitos adversos , Diabetes Mellitus Tipo 1/etiologia , Exposição Ambiental/efeitos adversos , Feminino , Seguimentos , Trato Gastrointestinal/microbiologia , Humanos , Lactente , Alimentos Infantis , Fenômenos Fisiológicos da Nutrição do Lactente , Masculino , Fatores de Risco
13.
PLoS One ; 9(3): e90784, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24614698

RESUMO

BACKGROUND: Preterm birth is the second leading cause of death in children under the age of five years worldwide, but the etiology of many cases remains enigmatic. The dogma that the fetus resides in a sterile environment is being challenged by recent findings and the question has arisen whether microbes that colonize the fetus may be related to preterm birth. It has been posited that meconium reflects the in-utero microbial environment. In this study, correlations between fetal intestinal bacteria from meconium and gestational age were examined in order to suggest underlying mechanisms that may contribute to preterm birth. METHODS: Meconium from 52 infants ranging in gestational age from 23 to 41 weeks was collected, the DNA extracted, and 16S rRNA analysis performed. Resulting taxa of microbes were correlated to clinical variables and also compared to previous studies of amniotic fluid and other human microbiome niches. FINDINGS: Increased detection of bacterial 16S rRNA in meconium of infants of <33 weeks gestational age was observed. Approximately 61·1% of reads sequenced were classified to genera that have been reported in amniotic fluid. Gestational age had the largest influence on microbial community structure (R = 0·161; p = 0·029), while mode of delivery (C-section versus vaginal delivery) had an effect as well (R = 0·100; p = 0·044). Enterobacter, Enterococcus, Lactobacillus, Photorhabdus, and Tannerella, were negatively correlated with gestational age and have been reported to incite inflammatory responses, suggesting a causative role in premature birth. INTERPRETATION: This provides the first evidence to support the hypothesis that the fetal intestinal microbiome derived from swallowed amniotic fluid may be involved in the inflammatory response that leads to premature birth.


Assuntos
Bactérias/metabolismo , Mecônio/microbiologia , Microbiota , Nascimento Prematuro/microbiologia , Líquido Amniótico/microbiologia , Biodiversidade , Biomarcadores/metabolismo , Contagem de Colônia Microbiana , Fatores de Confusão Epidemiológicos , Parto Obstétrico , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Mediadores da Inflamação/metabolismo , Gravidez , Proteína S100A12/metabolismo
14.
Front Microbiol ; 5: 678, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25540641

RESUMO

The incidence of the autoimmune disease, type 1 diabetes (T1D), has increased dramatically over the last half century in many developed countries and is particularly high in Finland and other Nordic countries. Along with genetic predisposition, environmental factors are thought to play a critical role in this increase. As with other autoimmune diseases, the gut microbiome is thought to play a potential role in controlling progression to T1D in children with high genetic risk, but we know little about how the gut microbiome develops in children with high genetic risk for T1D. In this study, the early development of the gut microbiomes of 76 children at high genetic risk for T1D was determined using high-throughput 16S rRNA gene sequencing. Stool samples from children born in the same hospital in Turku, Finland were collected at monthly intervals beginning at 4-6 months after birth until 2.2 years of age. Of those 76 children, 29 seroconverted to T1D-related autoimmunity (cases) including 22 who later developed T1D, the remaining 47 subjects remained healthy (controls). While several significant compositional differences in low abundant species prior to seroconversion were found, one highly abundant group composed of two closely related species, Bacteroides dorei and Bacteroides vulgatus, was significantly higher in cases compared to controls prior to seroconversion. Metagenomic sequencing of samples high in the abundance of the B. dorei/vulgatus group before seroconversion, as well as longer 16S rRNA sequencing identified this group as Bacteroides dorei. The abundance of B. dorei peaked at 7.6 months in cases, over 8 months prior to the appearance of the first islet autoantibody, suggesting that early changes in the microbiome may be useful for predicting T1D autoimmunity in genetically susceptible infants. The cause of increased B. dorei abundance in cases is not known but its timing appears to coincide with the introduction of solid food.

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