15 results on '"Bollyky JB"'
Search Results
2. Rapamycin/IL-2 combination therapy in patients with type 1 diabetes augments Tregs yet transiently impairs β-cell function.
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Long SA, Rieck M, Sanda S, Bollyky JB, Samuels PL, Goland R, Ahmann A, Rabinovitch A, Aggarwal S, Phippard D, Turka LA, Ehlers MR, Bianchine PJ, Boyle KD, Adah SA, Bluestone JA, Buckner JH, Greenbaum CJ, for Diabetes TrialNet and the Immune Tolerance Network, and Long, S Alice
- Abstract
Rapamycin/interleukin-2 (IL-2) combination treatment of NOD mice effectively treats autoimmune diabetes. We performed a phase 1 clinical trial to test the safety and immunologic effects of rapamycin/IL-2 combination therapy in type 1 diabetic (T1D) patients. Nine T1D subjects were treated with 2-4 mg/day rapamycin orally for 3 months and 4.5 × 10(6) IU IL-2 s.c. three times per week for 1 month. β-Cell function was monitored by measuring C-peptide. Immunologic changes were monitored using flow cytometry and serum analyses. Regulatory T cells (Tregs) increased within the first month of therapy, yet clinical and metabolic data demonstrated a transient worsening in all subjects. The increase in Tregs was transient, paralleling IL-2 treatment, whereas the response of Tregs to IL-2, as measured by STAT5 phosphorylation, increased and persisted after treatment. No differences were observed in effector T-cell subset frequencies, but an increase in natural killer cells and eosinophils occurred with IL-2 therapy. Rapamycin/IL-2 therapy, as given in this phase 1 study, resulted in transient β-cell dysfunction despite an increase in Tregs. Such results highlight the difficulties in translating therapies to the clinic and emphasize the importance of broadly interrogating the immune system to evaluate the effects of therapy. [ABSTRACT FROM AUTHOR]
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- 2012
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3. Association of protective behaviors with SARS-CoV-2 infection: results from a longitudinal cohort study of adults in the San Francisco Bay Area.
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Judson TJ, Zhang S, Lindan CP, Boothroyd D, Grumbach K, Bollyky JB, Sample HA, Huang B, Desai M, Gonzales R, Maldonado Y, and Rutherford G
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- Adult, Humans, SARS-CoV-2, Pandemics prevention & control, Longitudinal Studies, RNA, Viral, San Francisco epidemiology, Cohort Studies, COVID-19 epidemiology, COVID-19 prevention & control
- Abstract
Purpose: In an effort to decrease transmission during the first years of the COVID-19 pandemic, public health officials encouraged masking, social distancing, and working from home, and restricted travel. However, many studies of the effectiveness of these measures had significant methodologic limitations. In this analysis, we used data from the TrackCOVID study, a longitudinal cohort study of a population-based sample of 3846 adults in the San Francisco Bay Area, to evaluate the association between self-reported protective behaviors and incidence of SARS-CoV-2 infection., Methods: Participants without SARS-CoV2 infection were enrolled from August to December 2020 and followed monthly with testing and surveys (median of four visits)., Results: A total of 118 incident infections occurred (3.0% of participants). At baseline, 80.0% reported always wearing a mask; 56.0% avoided contact with nonhousehold members some/most of the time; 9.6% traveled outside the state; and 16.0% worked 20 or more hours per week outside the home. Factors associated with incident infection included being Black or Latinx, having less than a college education, and having more household residents. The only behavioral factor associated with incident infection was working outside the home (adjusted hazard ratio 1.62, 95% confidence interval 1.02-2.59)., Conclusions: Focusing on protecting people who cannot work from home could help prevent infections during future waves of COVID-19, or future pandemics from respiratory viruses. This focus must be balanced with the known importance of directing resources toward those at risk of severe infections., Competing Interests: Declaration of Competing Interest The authors have no competing interests to disclose., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)
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- 2023
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4. Incidence and Prevalence of Coronavirus Disease 2019 Within a Healthcare Worker Cohort During the First Year of the Severe Acute Respiratory Syndrome Coronavirus 2 Pandemic.
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Doernberg SB, Holubar M, Jain V, Weng Y, Lu D, Bollyky JB, Sample H, Huang B, Craik CS, Desai M, Rutherford GW, and Maldonado Y
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- Humans, Pandemics prevention & control, Incidence, Prevalence, Longitudinal Studies, Health Personnel, Cohort Studies, SARS-CoV-2, COVID-19 epidemiology
- Abstract
Background: Preventing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2_ infections in healthcare workers (HCWs) is critical for healthcare delivery. We aimed to estimate and characterize the prevalence and incidence of coronavirus disease 2019 (COVID-19) in a US HCW cohort and to identify risk factors associated with infection., Methods: We conducted a longitudinal cohort study of HCWs at 3 Bay Area medical centers using serial surveys and SARS-CoV-2 viral and orthogonal serological testing, including measurement of neutralizing antibodies. We estimated baseline prevalence and cumulative incidence of COVID-19. We performed multivariable Cox proportional hazards models to estimate associations of baseline factors with incident infections and evaluated the impact of time-varying exposures on time to COVID-19 using marginal structural models., Results: A total of 2435 HCWs contributed 768 person-years of follow-up time. We identified 21 of 2435 individuals with prevalent infection, resulting in a baseline prevalence of 0.86% (95% confidence interval [CI], .53%-1.32%). We identified 70 of 2414 incident infections (2.9%), yielding a cumulative incidence rate of 9.11 cases per 100 person-years (95% CI, 7.11-11.52). Community contact with a known COVID-19 case was most strongly correlated with increased hazard for infection (hazard ratio, 8.1 [95% CI, 3.8-17.5]). High-risk work-related exposures (ie, breach in protective measures) drove an association between work exposure and infection (hazard ratio, 2.5 [95% CI, 1.3-4.8). More cases were identified in HCWs when community case rates were high., Conclusions: We observed modest COVID-19 incidence despite consistent exposure at work. Community contact was strongly associated with infections, but contact at work was not unless accompanied by high-risk exposure., Competing Interests: Potential conflicts of interest . S. B. D. has received coronavirus disease 2019 (COVID-19) research funding from Gilead and the National Institutes of Health (NIH) and has served as a consultant to and received non–COVID-19 research funding from Genentech, Basilea, and the NIH. G. W. R. has received grant funding from the Centers for Disease Control and Prevention and the California Department of Public Health, has served as a consultant regarding adverse events for Moderna, and has provided expert declarations and depositions for the California Department of Justice. Y. M. has received funding from Pfizer (grants C3671008 and C4591007), the NIH (grants U54 MD010724, U54 MD010724-05S1, R21AI148810, P30AG059307, and 000522211-022), the Bill & Melinda Gates Foundation (grant OPP1113682), and the Chan Zuckerberg Foundation (grant 12089sc); has served as an advisor for and received payment or honoraria from the American Academy of Pediatrics; and has served on a data safety monitoring board for Pfizer. All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2022. Published by Oxford University Press for the Infectious Diseases Society of America.)
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- 2022
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5. Oral hymecromone decreases hyaluronan in human study participants.
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Rosser JI, Nagy N, Goel R, Kaber G, Demirdjian S, Saxena J, Bollyky JB, Frymoyer AR, Pacheco-Navarro AE, Burgener EB, Rajadas J, Wang Z, Arbach O, Dunn CE, Kalinowski A, Milla CE, and Bollyky PL
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- Administration, Oral, COVID-19, Europe, Extracellular Matrix metabolism, Humans, Hyaluronic Acid metabolism, Hymecromone administration & dosage, Hymecromone adverse effects
- Abstract
BACKGROUNDHyaluronan (HA), an extracellular matrix glycosaminoglycan, has been implicated in the pathophysiology of COVID-19 infection, pulmonary hypertension, pulmonary fibrosis, and other diseases, but is not targeted by any approved drugs. We asked whether hymecromone (4-methylumbelliferone [4-MU]), an oral drug approved in Europe for biliary spasm treatment that also inhibits HA in vitro and in animal models, could be repurposed as an inhibitor of HA synthesis in humans.METHODSWe conducted an open-label, single-center, dose-response study of hymecromone in healthy adults. Subjects received hymecromone at 1200 (n = 8), 2400 (n = 9), or 3600 (n = 9) mg/d divided into 3 doses daily, administered orally for 4 days. We assessed safety and tolerability of hymecromone and analyzed HA, 4-MU, and 4-methylumbelliferyl glucuronide (4-MUG; the main metabolite of 4-MU) concentrations in sputum and serum.RESULTSHymecromone was well tolerated up to doses of 3600 mg/d. Both sputum and serum drug concentrations increased in a dose-dependent manner, indicating that higher doses lead to greater exposures. Across all dose arms combined, we observed a significant decrease in sputum HA from baseline after 4 days of treatment. We also observed a decrease in serum HA. Additionally, higher baseline sputum HA levels were associated with a greater decrease in sputum HA.CONCLUSIONAfter 4 days of exposure to oral hymecromone, healthy human subjects experienced a significant reduction in sputum HA levels, indicating this oral therapy may have potential in pulmonary diseases where HA is implicated in pathogenesis.TRIAL REGISTRATIONClinicalTrials.gov NCT02780752.FUNDINGStanford Medicine Catalyst, Stanford SPARK, Stanford Innovative Medicines Accelerator program, NIH training grants 5T32AI052073-14 and T32HL129970.
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- 2022
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6. Figure Correction: The Effect of a Cellular-Enabled Glucose Meter on Glucose Control for Patients With Diabetes: Prospective Pre-Post Study.
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Bollyky JB, Melton ST, Xu T, Painter SL, and Knox B
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[This corrects the article DOI: 10.2196/14799.]., (©Jennifer B Bollyky, Stephanie T Melton, Tong Xu, Stefanie L Painter, Brian Knox. Originally published in JMIR Diabetes (http://diabetes.jmir.org), 28.07.2020.)
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- 2020
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7. The Effect of a Cellular-Enabled Glucose Meter on Glucose Control for Patients With Diabetes: Prospective Pre-Post Study.
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Bollyky JB, Melton ST, Xu T, Painter SL, and Knox B
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Background: Diabetes is a global epidemic affecting approximately 30 million people in the United States. The World Health Organization recommends using technology and telecommunications to improve health care delivery and disease management. The Livongo for Diabetes Program offers a remote monitoring technology with Certified Diabetes Educator outreach., Objective: The purpose of this study was to examine health outcomes measured by changes in HbA
1c , in time in target blood glucose range, and in depression symptoms for patients enrolled in a remote digital diabetes management program in a Diabetes Center of Excellence setting., Methods: The impact of the Livongo for Diabetes program on hemoglobin A1c (HbA1c ), blood glucose ranges, and depression screening survey results (Patient Health Questionnaire-2 [PHQ-2]) were assessed over 12 months in a prospective cohort recruited from the University of South Florida Health Diabetes Home for Healthy Living. Any patient ≥18 years old with a diagnosis of diabetes was approached for voluntary inclusion into the program. The analysis was a pre-post design for those members enrolled in the study. Data was collected at outpatient clinic visits and remotely through the Livongo glucose meter., Results: A total of 86 adults were enrolled into the Livongo for Diabetes program, with 49% (42/86) female, an average age of 50 (SD 15) years, 56% (48/86) with type 2 diabetes mellitus, and 69% (59/86) with insulin use. The mean HbA1c drop amongst the group was 0.66% (P=.17), with all participants showing a decline in HbA1c at 12 months. A 17% decrease of blood glucose checks <70 mg/dL occurred concurrently. Participants with type 2 diabetes not using insulin had blood glucose values within target range (70-180 mg/dL) 89% of the time. Participants with type 2 diabetes using insulin were in target range 68% of the time, and type 1 diabetes 58% of the time. Average PHQ-2 scores decreased by 0.56 points during the study period., Conclusions: Participants provided with a cellular-enabled blood glucose meter with real-time feedback and access to coaching from a certified diabetes educator in an outpatient clinical setting experienced improved mean glucose values and fewer episodes of hypoglycemia relative to the start of the program., (©Jennifer B Bollyky, Stephanie T Melton, Tong Xu, Stefanie L Painter, Brian Knox. Originally published in JMIR Diabetes (http://diabetes.jmir.org), 07.10.2019.)- Published
- 2019
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8. Reduced medical spending associated with increased use of a remote diabetes management program and lower mean blood glucose values.
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Whaley CM, Bollyky JB, Lu W, Painter S, Schneider J, Zhao Z, He X, Johnson J, and Meadows ES
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- Adolescent, Adult, Blood Glucose, Blood Glucose Self-Monitoring, Child, Cost-Benefit Analysis, Diabetes Mellitus, Type 2 blood, Female, Health Expenditures statistics & numerical data, Health Resources statistics & numerical data, Health Services statistics & numerical data, Humans, Insurance Claim Review, Male, Middle Aged, Retrospective Studies, Wearable Electronic Devices, Young Adult, Diabetes Mellitus, Type 2 economics, Diabetes Mellitus, Type 2 therapy, Self-Management economics, Self-Management methods, Telemedicine economics, Telemedicine methods
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Aims: Many new mobile technologies are available to assist people in managing chronic conditions, but data on the association between the use of these technologies and medical spending remains limited. As the available digital technology offerings to aid in diabetes management increase, it is important to understand their impact on medical spending. The aim of this study was to investigate the financial impact of a remote digital diabetes management program using medical claims and real-time blood glucose data. Materials and methods: A retrospective analysis of multivariate difference-in-difference and instrumental variables regression modeling was performed using data collected from a remote digital diabetes management program. All employees with diabetes were invited, in a phased introduction, to join the program. Data included blood glucose (BG) values captured remotely from members via connected BG meters and medical spending claims. Participants included members (those who accepted the invitation, n = 2,261) and non-members ( n = 8,741) who received health insurance benefits from three self-insured employers. Medical spending was compared between people with well-controlled (BG ≤ 154 mg/dL) and poorly controlled (BG > 154 mg/dL) diabetes. Results: Program access was associated with a 21.9% ( p < 0.01) decrease in medical spending, which translates into a $88 saving per member per month at 1 year. Compared to non-members, members experienced a 10.7% ( p < 0.01) reduction in diabetes-related medical spending and a 24.6% ( p < 0.01) reduction in spending on office-based services. Well-controlled BG values were associated with 21.4% ( p = 0.03) lower medical spending. Limitations and conclusions: Remote digital diabetes management is associated with decreased medical spending at 1 year. Reductions in spending increased with active utilization. It will be beneficial for future studies to analyze the long-term effects of the remote diabetes management program and assess impacts on patient health and well-being.
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- 2019
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9. Remote Lifestyle Coaching Plus a Connected Glucose Meter with Certified Diabetes Educator Support Improves Glucose and Weight Loss for People with Type 2 Diabetes.
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Bollyky JB, Bravata D, Yang J, Williamson M, and Schneider J
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- Adult, Blood Glucose Self-Monitoring, Diabetes Mellitus, Type 2 blood, Diabetes Mellitus, Type 2 physiopathology, Female, Humans, Male, Mentoring, Middle Aged, Treatment Outcome, Blood Glucose analysis, Diabetes Mellitus, Type 2 therapy, Life Style, Patient Education as Topic, Remote Consultation, Weight Loss physiology
- Abstract
Background: Connected health devices with lifestyle coaching can provide real-time support for people with type 2 diabetes (T2D). However, the intensity of lifestyle coaching needed to achieve outcomes is unknown., Methods: Livongo provides connected, two-way messaging glucose meters, unlimited blood glucose (BG) test strips, and access to certified diabetes educators. We evaluated the incremental effects of adding lifestyle coaching on BG, estimated HbA1c, and weight. We randomized 330 eligible adults (T2D, HbA1c > 7.5%, BMI ≥ 25) to receive no further intervention ( n = 75), a connected scale ( n = 115), scale plus lightweight coaching ( n = 73), or scale plus intense coaching ( n = 67) for 12 weeks. We evaluated the change in outcomes using ANOVA., Results: Livongo participation alone resulted in improved BG control (mean HbA1c declined: 8.5% to 7.5%, p = 0.01). Mean weight loss and additional BG decreases were higher in the intensive compared with the lightweight coaching and scale-only groups (weight change (lb): -6.4, -4.1, and -1.1, resp., p = 0.01; BG change (mg/dL): -19.4, -11.3, and -2.9, resp., p = 0.02). The estimated 12-week program costs were 5.5 times more for intensive than lightweight coaching., Conclusion: Livongo participation significantly improves BG control in people with T2D. Additional lifestyle coaching may be a cost-effective intervention to achieve further glucose control and weight loss.
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- 2018
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10. Elimination diet and the development of multiple tree-nut allergies.
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Elizur A, Bollyky JB, and Block WM
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- Adolescent, Age of Onset, Allergens immunology, Biomarkers blood, Child, Child, Preschool, Female, Humans, Immunoglobulin E blood, Intradermal Tests, Male, Nut Hypersensitivity diagnosis, Nut Hypersensitivity immunology, Nuts immunology, Plant Proteins immunology, Predictive Value of Tests, Retrospective Studies, Surveys and Questionnaires, Allergens adverse effects, Nut Hypersensitivity diet therapy, Nuts adverse effects, Plant Proteins adverse effects
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BackgroundDespite its high prevalence, relatively little is known about the characteristics of patients with multiple tree-nut allergies.MethodsPatients (n=60, aged 4-15 years), recruited for a multiple food (tree nuts, peanut, milk, egg, soy, sesame, and wheat) oral immunotherapy (OIT) study, filled a questionnaire on their initial allergy evaluation. Medical records were reviewed. At OIT enrollment (median interval, 7.5 years), patients underwent oral food challenges (OFCs) to foods still eliminated.ResultsThere was significantly less evidence for eliminating tree nuts compared with other foods, as reflected by a lower rate of acute reaction to the offending food, either as the trigger for initial allergy evaluation (5.9% for tree-nuts vs. 20-40% for other foods, respectively P<0.001) or later in life (14.5% vs. 38-75%, respectively P=0.001), and a higher rate of negative skin prick test (SPT)/specific IgE (sIgE) at initial diagnosis (25% vs. <10%, P<0.001). SPT/sIgE increased significantly from past initial levels to present for tree nuts (P<0.001) and peanut (P=0.001) but not for other foods, and most OFCs performed at present were positive.ConclusionsTree nuts are often eliminated from the diet of multiple-food-allergic patients, despite their low probability for allergy. Sensitization and allergy to most tree nuts exist years later, suggesting that it developed during the period of elimination.
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- 2017
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11. Association of Clinical Reactivity with Sensitization to Allergen Components in Multifood-Allergic Children.
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Andorf S, Borres MP, Block W, Tupa D, Bollyky JB, Sampath V, Elizur A, Lidholm J, Jones JE, Galli SJ, Chinthrajah RS, and Nadeau KC
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- Adolescent, Child, Child, Preschool, Egg Proteins immunology, Female, Humans, Immunoglobulin E blood, Male, Milk Proteins immunology, Molecular Mimicry, Prunus dulcis immunology, Skin Tests, Allergens immunology, Cross Reactions, Food Hypersensitivity immunology
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Background: Thirty percent of children with food allergies have multiple simultaneous allergies; however, the features of these multiple allergies are not well characterized serologically or clinically., Objective: We comprehensively evaluated 60 multifood-allergic patients by measuring serum IgE to key allergen components, evaluating clinical histories and medication use, performing skin tests, and conducting double-blind, placebo-controlled food challenges (DBPCFCs)., Methods: Sixty participants with multiple food allergies were characterized by clinical history, DBPCFCs, total IgE, specific IgE, and component-resolved diagnostics (IgE and IgG4) data. The food allergens tested were almond, egg, milk, sesame, peanut, pecan, walnut, hazelnut, cashew, pistachio, soy, and wheat., Results: Our data demonstrate that of the reactions observed during a graded DBPCFC, gastrointestinal reactions occurred more often in boys than in girls, as well as in individuals with high levels of IgE to 2S albumins from cashew, walnut, and hazelnut. Certain food allergies often occurred concomitantly in individuals (ie, cashew/pistachio and walnut/pecan/hazelnut). IgE testing to components further corroborated serological relationships between and among these clustered food allergies., Conclusions: Associations of certain food allergies were shown by DBPCFC outcomes as well as by correlations in IgE reactivity to structurally related food allergen components. Each of these criteria independently demonstrated a significant association between allergies to cashew and pistachio, as well as among allergies to walnut, pecan, and hazelnut., (Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)
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- 2017
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12. Heterogeneity in recent-onset type 1 diabetes - a clinical trial perspective.
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Bollyky JB, Xu P, Butte AJ, Wilson DM, Beam CA, and Greenbaum CJ
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- Adolescent, Adult, Age Factors, Autoantibodies analysis, Biomarkers blood, Body Mass Index, C-Peptide blood, Child, Cohort Studies, Diabetes Mellitus, Type 1 blood, Diabetes Mellitus, Type 1 immunology, Diabetes Mellitus, Type 1 metabolism, Humans, Italy, Middle Aged, North America, Young Adult, Diabetes Mellitus, Type 1 complications, Leukopenia complications, Lymphopenia complications, Obesity complications, Overweight complications, Pediatric Obesity complications
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Background: Type 1 diabetes (T1D) TrialNet is a National Institutes of Health-sponsored clinical trial network aimed at altering the disease course of T1D. The purpose of this study is to evaluate age-dependent heterogeneity in clinical, metabolic and immunologic characteristics of individuals with recent-onset T1D, to identify cohorts of interest and to aid in planning of future studies., Methods: Eight hundred eighty-three individuals with recent-onset T1D involved in five TrialNet studies were categorized by age as follows: ≥18 years, 12-17 years, 8-12 years and <8 years. Data were compared with healthy age-matched subjects in the National Health and Nutrition Examination Survey., Results: Only 2.0% of the individuals overall were excluded from trial participation because of insufficient C-peptide values (<0.2 pmol/mL). A disproportionate number of these subjects were <8 years old. Leukopenia was present in 21.2% of individuals and lymphopenia in 11.6%; these frequencies were markedly higher than age-matched healthy National Health and Nutrition Examination Survey population. Of the cohort, 24.5% were overweight or obese. Neither high-risk human leukocyte antigen type DR3 nor DR4 was present in 31% of adults and 21% of children., Conclusions: The ability of recent-onset T1D patients to meet key entry criteria for TrialNet studies, including C-peptide >0.2 pmol/mL, varies by age. Lower C-peptide level requirements for younger participants and other aspects of heterogeneity of recent-onset T1D patients, such as white blood cell count abnormalities and body mass index should be considered in the design of future clinical studies., (Copyright © 2015 John Wiley & Sons, Ltd.)
- Published
- 2015
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13. 4-methylumbelliferone treatment and hyaluronan inhibition as a therapeutic strategy in inflammation, autoimmunity, and cancer.
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Nagy N, Kuipers HF, Frymoyer AR, Ishak HD, Bollyky JB, Wight TN, and Bollyky PL
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Hyaluronan (HA) is a prominent component of the extracellular matrix at many sites of chronic inflammation, including type 1 diabetes (T1D), multiple sclerosis, and numerous malignancies. Recent publications have demonstrated that when HA synthesis is inhibited using 4-methylumbelliferone (4-MU), beneficial effects are observed in several animal models of these diseases. Notably, 4-MU is an already approved drug in Europe and Asia called "hymecromone" where it is used to treat biliary spasm. However, there is uncertainty regarding how 4-MU treatment provides benefit in these animal models and the potential long-term consequences of HA inhibition. Here, we review what is known about how HA contributes to immune dysregulation and tumor progression. Then, we review what is known about 4-MU and hymecromone in terms of mechanism of action, pharmacokinetics, and safety. Finally, we review recent studies detailing the use of 4-MU to treat animal models of cancer and autoimmunity.
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- 2015
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14. Evaluation of in vivo T cell kinetics: use of heavy isotope labelling in type 1 diabetes.
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Bollyky JB, Long SA, Fitch M, Bollyky PL, Rieck M, Rogers R, Samuels PL, Sanda S, Buckner JH, Hellerstein MK, and Greenbaum CJ
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- Adolescent, Adult, CD4-Positive T-Lymphocytes pathology, Case-Control Studies, Cell Proliferation, Deoxyribose metabolism, Deuterium Oxide metabolism, Diabetes Mellitus, Type 1 pathology, Female, Humans, Immunologic Memory, Kinetics, Male, Middle Aged, T-Lymphocyte Subsets immunology, T-Lymphocyte Subsets metabolism, T-Lymphocyte Subsets pathology, T-Lymphocytes, Regulatory immunology, T-Lymphocytes, Regulatory metabolism, T-Lymphocytes, Regulatory pathology, Young Adult, CD4-Positive T-Lymphocytes immunology, CD4-Positive T-Lymphocytes metabolism, Diabetes Mellitus, Type 1 immunology, Diabetes Mellitus, Type 1 metabolism
- Abstract
CD4(+) memory cell development is dependent upon T cell receptor (TCR) signal strength, antigen dose and the cytokine milieu, all of which are altered in type 1 diabetes (T1D). We hypothesized that CD4(+) T cell turnover would be greater in type 1 diabetes subjects compared to controls. In vitro studies of T cell function are unable to evaluate dynamic aspects of immune cell homoeostasis. Therefore, we used deuterium oxide ((2) H(2)O) to assess in vivo turnover of CD4(+) T cell subsets in T1D (n = 10) and control subjects (n = 10). Serial samples of naive, memory and regulatory (T(reg)) CD4(+) T cell subsets were collected and enrichment of deoxyribose was determined by gas chromatography-mass spectrometry (GC-MS). Quantification of T cell turnover was performed using mathematical models to estimate fractional enrichment (f, n = 20), turnover rate (k, n = 20), proliferation (p, n = 10) and disappearance (d*, n = 10). Although turnover of T(regs) was greater than memory and naive cells in both controls and T1D subjects, no differences were seen between T1D and controls in T(reg) or naive kinetics. However, turnover of CD4(+) memory T cells was faster in those with T1D compared to control subjects. Measurement and modelling of incorporated deuterium is useful for evaluating the in vivo kinetics of immune cells in T1D and could be incorporated into studies of the natural history of disease or clinical trials designed to alter the disease course. The enhanced CD4(+) memory T cell turnover in T1D may be important in understanding the pathophysiology and potential treatments of autoimmune diabetes., (© 2013 British Society for Immunology.)
- Published
- 2013
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15. The role of hyaluronan and the extracellular matrix in islet inflammation and immune regulation.
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Bollyky PL, Bogdani M, Bollyky JB, Hull RL, and Wight TN
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- Animals, Diabetes Mellitus, Type 1 immunology, Diabetes Mellitus, Type 1 metabolism, Humans, Hyaluronan Receptors metabolism, Models, Biological, Extracellular Matrix metabolism, Hyaluronic Acid metabolism, Islets of Langerhans metabolism
- Abstract
Type 1 diabetes (T1D) is a disease that in most individuals results from autoimmune attack of a single tissue type, the pancreatic islet. A fundamental, unanswered question in T1D pathogenesis is how the islet tissue environment influences immune regulation. This crosstalk is likely to be communicated through the extracellular matrix (ECM). Here, we review what is known about the ECM in insulitis and examine how the tissue environment is synchronized with immune regulation. In particular, we focus on the role of hyaluronan (HA) and its interactions with Foxp3+ regulatory T-cells (Treg). We propose that HA is a "keystone molecule" in the inflammatory milieu and that HA, together with its associated binding proteins and receptors, is an appropriate point of entry for investigations into how ECM influences immune regulation in the islet.
- Published
- 2012
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