27 results on '"Hansen DW"'
Search Results
2. Dying of pestilence: Stature and mortality from the Black Death in 14th-century Kyrgyzstan.
- Author
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Hansen DW, DeWitte SN, and Slavin P
- Subjects
- Humans, Kyrgyzstan epidemiology, Male, Female, Adult, History, Medieval, Young Adult, Middle Aged, Archaeology, Cemeteries history, Adolescent, Anthropology, Physical, Plague history, Plague mortality, Plague epidemiology, Body Height
- Abstract
Objectives: Bioarchaeological studies have provided important information about mortality patterns during the second pandemic of plague, including the Black Death, but most to date have focused on European contexts. This study represents a spatial contribution to plague bioarchaeology, focusing on Central Asia, the origin of the second pandemic. We examine the relationship between stature and plague mortality during an outbreak of plague at Kara-Djigach in northern Kyrgyzstan in 1338-1339, the earliest archaeological site known to contain victims of the Black Death in Eurasia., Methods: This study uses epigraphic data and in situ measurements from the Syriac Christian cemeteries at Kara-Djigach, obtained from field notes from excavations conducted by Russian archaeologists in the 1880s (n = 34 individuals). The epigraphic data provide detailed information about the interred individuals, including occupations, year of death, and gender. In situ measurements provide data on adult stature. This study uses chi-square and Fisher's exact tests to examine relationships between stature and plague at the site., Results: We find evidence that relatively short people were disproportionately affected by plague when compared with non-plague years., Discussion: These results might reflect increased mortality risks from plague based on exposure to early life biological stress events., (© 2024 Wiley Periodicals LLC.)
- Published
- 2024
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3. Psychosocial outcomes with the Omnipod® 5 Automated Insulin Delivery System in caregivers of very young children with type 1 diabetes.
- Author
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MacLeish SA, Hood KK, Polonsky WH, Wood JR, Bode BW, Forlenza GP, Laffel LM, Buckingham BA, Criego AB, Schoelwer MJ, DeSalvo DJ, Sherr JL, Hansen DW, Conroy LR, Huyett LM, Vienneau TE, and Ly TT
- Subjects
- Humans, Child, Preschool, Female, Male, Hypoglycemia prevention & control, Hypoglycemia chemically induced, Surveys and Questionnaires, Sleep Quality, Adult, Diabetes Mellitus, Type 1 drug therapy, Diabetes Mellitus, Type 1 psychology, Diabetes Mellitus, Type 1 blood, Caregivers psychology, Insulin Infusion Systems, Insulin administration & dosage, Insulin therapeutic use, Hypoglycemic Agents administration & dosage, Hypoglycemic Agents therapeutic use
- Abstract
Aim: Automated insulin delivery (AID) systems have demonstrated improved glycaemic outcomes in people with type 1 diabetes (T1D), yet limited data exist on these systems in very young children and their impact on caregivers. We evaluated psychosocial outcomes following use of the tubeless Omnipod® 5 AID System in caregivers of very young children., Materials and Methods: This 3-month single-arm, multicentre, pivotal clinical trial enrolled 80 children aged 2.0-5.9 years with T1D to use the Omnipod 5 AID System. Caregivers completed questionnaires assessing psychosocial outcomes-diabetes distress (Problem Areas in Diabetes), hypoglycaemia confidence (Hypoglycemia Confidence Scale), well-being (World Health Organization 5 Well-Being Index), sleep quality (Pittsburgh Sleep Quality Index), insulin delivery satisfaction (Insulin Delivery Satisfaction Survey) and system usability (System Usability Scale) at baseline with standard therapy and after 3 months of AID use., Results: Following 3 months of Omnipod 5 use, caregivers experienced significant improvements across all measures, including diabetes-related psychosocial outcomes (Problem Areas in Diabetes; p < 0.0001, Hypoglycemia Confidence Scale; p < 0.01), well-being (World Health Organization 5 Well-Being Index; p < 0.0001) and perceived system usability (System Usability Scale; p < 0.0001). Significant improvements were seen in the Pittsburgh Sleep Quality Index total score and the overall sleep quality, sleep duration and efficiency subscales (all p < 0.05). Insulin Delivery Satisfaction Survey scores improved on all subscales (greater satisfaction, reduced burden and reduced inconvenience; all p < 0.0001)., Conclusions: Caregivers face unique challenges when managing T1D in very young children. While glycaemic metrics have unquestioned importance, these results evaluating psychosocial outcomes reveal additional meaningful benefits and suggest that the Omnipod 5 AID System alleviates some of the burdens caregivers face with diabetes management., (© 2024 Insulet Corporation and The Author(s). Diabetes, Obesity and Metabolism published by John Wiley & Sons Ltd.)
- Published
- 2024
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4. Glycemic Outcomes Persist for up to 2 Years in Very Young Children with the Omnipod ® 5 Automated Insulin Delivery System.
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DeSalvo DJ, Bode BW, Forlenza GP, Laffel LM, Buckingham BA, Criego AB, Schoelwer M, MacLeish SA, Sherr JL, Hansen DW, and Ly TT
- Subjects
- Humans, Child, Preschool, Female, Male, Hypoglycemia prevention & control, Treatment Outcome, Glycemic Control methods, Blood Glucose Self-Monitoring, Diabetes Mellitus, Type 1 drug therapy, Diabetes Mellitus, Type 1 blood, Insulin Infusion Systems, Insulin administration & dosage, Insulin therapeutic use, Blood Glucose analysis, Hypoglycemic Agents administration & dosage, Hypoglycemic Agents therapeutic use, Glycated Hemoglobin analysis
- Abstract
Background: To evaluate the long-term safety and effectiveness of the Omnipod
® 5 Automated Insulin Delivery (AID) System in very young children with type 1 diabetes with up to 2 years of use. Methods: Following a 13-week single-arm, multicenter, pivotal trial that took place after 14 days of standard therapy data collection, participating children (2-5.9 years of age at study enrollment) were provided the option to continue use of the AID system in an extension phase. HbA1c was measured every 3 months, up to 15 months of total use, and continuous glucose monitor metrics were collected through the completion of the extension study (for up to 2 years). Results: Participants ( N = 80) completed 18.2 [17.4, 23.4] (median [interquartile range]) total months of AID, inclusive of the 3-month pivotal trial. During the pivotal trial, HbA1c decreased from 7.4% ± 1.0% (57 ± 10.9 mmol/mol) to 6.9% ± 0.7% (52 ± 7.7 mmol/mol, P < 0.0001) and was maintained at 7.0% ± 0.7% (53 ± 7.7 mmol/mol) after 15 months total use ( P < 0.0001 from baseline). Time in target range (70-180 mg/dL) increased from 57.2% ± 15.3% during standard therapy to 68.1% ± 9.0% during the pivotal trial ( P < 0.0001) and was maintained at 67.2% ± 9.3% during the extension phase ( P < 0.0001 from standard therapy). Participants spent a median 97.1% of time in Automated Mode during the extension phase, with one episode of severe hypoglycemia and one episode of diabetic ketoacidosis. Conclusion: This evaluation of the Omnipod 5 AID System indicates that long-term use can safely maintain improvements in glycemic outcomes with up to 2 years of use in very young children with type 1 diabetes. Clinical Trials Registration Number: NCT04476472.- Published
- 2024
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5. Retraction Note: Eye tracking: empirical foundations for a minimal reporting guideline.
- Author
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Holmqvist K, Örbom SL, Hooge ITC, Niehorster DC, Alexander RG, Andersson R, Benjamins JS, Blignaut P, Brouwer AM, Chuang LL, Dalrymple KA, Drieghe D, Dunn MJ, Ettinger U, Fiedler S, Foulsham T, van der Geest JN, Hansen DW, Hutton SB, Kasneci E, Kingstone A, Knox PC, Kok EM, Lee H, Lee JY, Leppänen JM, Macknik S, Majaranta P, Martinez-Conde S, Nuthmann A, Nyström M, Orquin JL, Otero-Millan J, Park SY, Popelka S, Proudlock F, Renkewitz F, Roorda A, Schulte-Mecklenbeck M, Sharif B, Shic F, Shovman M, Thomas MG, Venrooij W, Zemblys R, and Hessels RS
- Published
- 2024
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6. Two Years with a Tubeless Automated Insulin Delivery System: A Single-Arm Multicenter Trial in Children, Adolescents, and Adults with Type 1 Diabetes.
- Author
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Criego AB, Carlson AL, Brown SA, Forlenza GP, Bode BW, Levy CJ, Hansen DW, Hirsch IB, Bergenstal RM, Sherr JL, Mehta SN, Laffel LM, Shah VN, Bhargava A, Weinstock RS, MacLeish SA, DeSalvo DJ, Jones TC, Aleppo G, Buckingham BA, and Ly TT
- Subjects
- Adult, Child, Humans, Adolescent, Hypoglycemic Agents therapeutic use, Insulin therapeutic use, Glycated Hemoglobin, Insulin Infusion Systems, Blood Glucose, Blood Glucose Self-Monitoring, Diabetes Mellitus, Type 1 drug therapy
- Abstract
Background: The Omnipod
® 5 Automated Insulin Delivery (AID) System was shown to be safe and effective following 3 months of use in people with type 1 diabetes (T1D); however, data on the durability of these results are limited. This study evaluated the long-term safety and effectiveness of Omnipod 5 use in people with T1D during up to 2 years of use. Materials and Methods: After a 3-month single-arm, multicenter, pivotal trial in children (6-13.9 years) and adolescents/adults (14-70 years), participants could continue system use in an extension phase. HbA1c was measured every 3 months for up to 15 months; continuous glucose monitor metrics were collected for up to 2 years. Results: Participants ( N = 224) completed median (interquartile range) 22.3 (21.7, 22.7) months of AID. HbA1c was reduced in the pivotal trial from 7.7% ± 0.9% in children and 7.2% ± 0.9% in adolescents/adults to 7.0% ± 0.6% and 6.8% ± 0.7%, respectively, ( P < 0.0001), and was maintained at 7.2% ± 0.7% and 6.9% ± 0.6% after 15 months ( P < 0.0001 from baseline). Time in target range (70-180 mg/dL) increased from 52.4% ± 15.6% in children and 63.6% ± 16.5% in adolescents/adults at baseline to 67.9% ± 8.0% and 73.8% ± 10.8%, respectively, during the pivotal trial ( P < 0.0001) and was maintained at 65.9% ± 8.9% and 72.9% ± 11.3% during the extension ( P < 0.0001 from baseline). One episode of diabetic ketoacidosis and seven episodes of severe hypoglycemia occurred during the extension. Children and adolescents/adults spent median 96.1% and 96.3% of time in Automated Mode, respectively. Conclusion: Our study supports that long-term use of the Omnipod 5 AID System can safely maintain improvements in glycemic outcomes for up to 2 years of use in people with T1D. Clinical Trials Registration Number: NCT04196140.- Published
- 2024
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7. Eye tracking: empirical foundations for a minimal reporting guideline.
- Author
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Holmqvist K, Örbom SL, Hooge ITC, Niehorster DC, Alexander RG, Andersson R, Benjamins JS, Blignaut P, Brouwer AM, Chuang LL, Dalrymple KA, Drieghe D, Dunn MJ, Ettinger U, Fiedler S, Foulsham T, van der Geest JN, Hansen DW, Hutton SB, Kasneci E, Kingstone A, Knox PC, Kok EM, Lee H, Lee JY, Leppänen JM, Macknik S, Majaranta P, Martinez-Conde S, Nuthmann A, Nyström M, Orquin JL, Otero-Millan J, Park SY, Popelka S, Proudlock F, Renkewitz F, Roorda A, Schulte-Mecklenbeck M, Sharif B, Shic F, Shovman M, Thomas MG, Venrooij W, Zemblys R, and Hessels RS
- Subjects
- Humans, Empirical Research, Eye-Tracking Technology, Eye Movements
- Abstract
In this paper, we present a review of how the various aspects of any study using an eye tracker (such as the instrument, methodology, environment, participant, etc.) affect the quality of the recorded eye-tracking data and the obtained eye-movement and gaze measures. We take this review to represent the empirical foundation for reporting guidelines of any study involving an eye tracker. We compare this empirical foundation to five existing reporting guidelines and to a database of 207 published eye-tracking studies. We find that reporting guidelines vary substantially and do not match with actual reporting practices. We end by deriving a minimal, flexible reporting guideline based on empirical research (Section "An empirically based minimal reporting guideline")., (© 2022. The Author(s).)
- Published
- 2023
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8. Modified Curcumins as Potential Drug Candidates for Breast Cancer: An Overview.
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Flint AL, Hansen DW, Brown LD, Stewart LE, Ortiz E, and Panda SS
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- Humans, Female, Solubility, Signal Transduction, Tumor Microenvironment, Curcumin pharmacology, Curcumin therapeutic use, Breast Neoplasms metabolism, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use
- Abstract
Breast cancer (BC), the most common malignancy in women, results from significant alterations in genetic and epigenetic mechanisms that alter multiple signaling pathways in growth and malignant progression, leading to limited long-term survival. Current studies with numerous drug therapies have shown that BC is a complex disease with tumor heterogeneity, rapidity, and dynamics of the tumor microenvironment that result in resistance to existing therapy. Targeting a single cell-signaling pathway is unlikely to treat or prevent BC. Curcumin (a natural yellow pigment), the principal ingredient in the spice turmeric, is well-documented for its diverse pharmacological properties including anti-cancer activity. However, its clinical application has been limited because of its low solubility, stability, and bioavailability. To overcome the limitation of curcumin, several modified curcumin conjugates and curcumin mimics were developed and studied for their anti-cancer properties. In this review, we have focused on the application of curcumin mimics and their conjugates for breast cancer.
- Published
- 2022
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9. Safety and Glycemic Outcomes With a Tubeless Automated Insulin Delivery System in Very Young Children With Type 1 Diabetes: A Single-Arm Multicenter Clinical Trial.
- Author
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Sherr JL, Bode BW, Forlenza GP, Laffel LM, Schoelwer MJ, Buckingham BA, Criego AB, DeSalvo DJ, MacLeish SA, Hansen DW, Ly TT, Sherr JL, Weyman K, Tichy E, VanName M, Brei M, Zgorski M, Steffen A, Carria L, Bode BW, Busby A, Forlenza GP, Wadwa RP, Slover R, Cobry E, Messer L, Laffel LM, Isganaitis E, Ambler-Osborn L, Freiner E, Turcotte C, Volkening L, Schoelwer M, Brown SA, Krauthause K, Emory E, Oliveri M, Buckingham BA, Ekhlaspour L, Kingman R, Criego AB, Schwartz BL, Gandrud LM, Grieme A, Hyatt J, DeSalvo DJ, McKay S, DeLaO K, Villegas C, MacLeish SA, Wood JR, Kaminski BA, Casey T, Campbell W, Behm K, Adams R, Hansen DW, Stone SL, Bzdick S, Bulger J, Agostini L, Doolittle S, Kivilaid K, Kleve K, Ly TT, Dumais B, Vienneau T, Huyett LM, Lee JB, O'Connor J, and Benjamin E
- Subjects
- Blood Glucose, Child, Child, Preschool, Glycated Hemoglobin analysis, Humans, Hypoglycemic Agents adverse effects, Insulin adverse effects, Insulin Infusion Systems, Insulin, Regular, Human therapeutic use, Diabetes Mellitus, Type 1 drug therapy, Diabetes Mellitus, Type 1 epidemiology, Hypoglycemia epidemiology
- Abstract
Objective: Very young children with type 1 diabetes often struggle to achieve glycemic targets, putting them at risk for long-term complications and creating an immense management burden for caregivers. We conducted the first evaluation of the Omnipod 5 Automated Insulin Delivery System in this population., Research Design and Methods: A total of 80 children aged 2.0-5.9 years used the investigational system in a single-arm study for 13 weeks following 14 days of baseline data collection with their usual therapy., Results: There were no episodes of severe hypoglycemia or diabetic ketoacidosis. By study end, HbA1c decreased by 0.55% (6.0 mmol/mol) (P < 0.0001). Time with sensor glucose levels in target range 70-180 mg/dL increased by 10.9%, or 2.6 h/day (P < 0.0001), while time with levels <70 mg/dL declined by median 0.27% (P = 0.0204)., Conclusions: Use of the automated insulin delivery system was safe, and participants experienced improved glycemic measures and reduced hypoglycemia during the study phase compared with baseline., (© 2022 by the American Diabetes Association.)
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- 2022
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10. High-Accuracy Gaze Estimation for Interpolation-Based Eye-Tracking Methods.
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Narcizo FB, Dos Santos FED, and Hansen DW
- Abstract
This study investigates the influence of the eye-camera location associated with the accuracy and precision of interpolation-based eye-tracking methods. Several factors can negatively influence gaze estimation methods when building a commercial or off-the-shelf eye tracker device, including the eye-camera location in uncalibrated setups. Our experiments show that the eye-camera location combined with the non-coplanarity of the eye plane deforms the eye feature distribution when the eye-camera is far from the eye's optical axis. This paper proposes geometric transformation methods to reshape the eye feature distribution based on the virtual alignment of the eye-camera in the center of the eye's optical axis. The data analysis uses eye-tracking data from a simulated environment and an experiment with 83 volunteer participants (55 males and 28 females). We evaluate the improvements achieved with the proposed methods using Gaussian analysis, which defines a range for high-accuracy gaze estimation between -0.5∘ and 0.5∘. Compared to traditional polynomial-based and homography-based gaze estimation methods, the proposed methods increase the number of gaze estimations in the high-accuracy range.
- Published
- 2021
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11. Multicenter Trial of a Tubeless, On-Body Automated Insulin Delivery System With Customizable Glycemic Targets in Pediatric and Adult Participants With Type 1 Diabetes.
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Brown SA, Forlenza GP, Bode BW, Pinsker JE, Levy CJ, Criego AB, Hansen DW, Hirsch IB, Carlson AL, Bergenstal RM, Sherr JL, Mehta SN, Laffel LM, Shah VN, Bhargava A, Weinstock RS, MacLeish SA, DeSalvo DJ, Jones TC, Aleppo G, Buckingham BA, and Ly TT
- Subjects
- Adolescent, Adult, Aged, Blood Glucose, Child, Glycated Hemoglobin analysis, Humans, Hypoglycemic Agents, Insulin Infusion Systems, Middle Aged, Prospective Studies, Young Adult, Diabetes Mellitus, Type 1 drug therapy, Insulin
- Abstract
Objective: Advances in diabetes technology have transformed the treatment paradigm for type 1 diabetes, yet the burden of disease is significant. We report on a pivotal safety study of the first tubeless, on-body automated insulin delivery system with customizable glycemic targets., Research Design and Methods: This single-arm, multicenter, prospective study enrolled 112 children (age 6-13.9 years) and 129 adults (age 14-70 years). A 2-week standard therapy phase (usual insulin regimen) was followed by 3 months of automated insulin delivery. Primary safety outcomes were incidence of severe hypoglycemia and diabetic ketoacidosis. Primary effectiveness outcomes were change in HbA
1c and percent time in sensor glucose range 70-180 mg/dL ("time in range")., Results: A total of 235 participants (98% of enrolled, including 111 children and 124 adults) completed the study. HbA1c was significantly reduced in children by 0.71% (7.8 mmol/mol) (mean ± SD: 7.67 ± 0.95% to 6.99 ± 0.63% [60 ± 10.4 mmol/mol to 53 ± 6.9 mmol/mol], P < 0.0001) and in adults by 0.38% (4.2 mmol/mol) (7.16 ± 0.86% to 6.78 ± 0.68% [55 ± 9.4 mmol/mol to 51 ± 7.4 mmol/mol], P < 0.0001). Time in range was improved from standard therapy by 15.6 ± 11.5% or 3.7 h/day in children and 9.3 ± 11.8% or 2.2 h/day in adults (both P < 0.0001). This was accomplished with a reduction in time in hypoglycemia <70 mg/dL among adults (median [interquartile range]: 2.00% [0.63, 4.06] to 1.09% [0.46, 1.75], P < 0.0001), while this parameter remained the same in children. There were three severe hypoglycemia events not attributable to automated insulin delivery malfunction and one diabetic ketoacidosis event from an infusion site failure., Conclusions: This tubeless automated insulin delivery system was safe and allowed participants to significantly improve HbA1c levels and time in target glucose range with a very low occurrence of hypoglycemia., (© 2021 by the American Diabetes Association.)- Published
- 2021
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12. The impact of physiological fatigue and gaze behavior on shooting performance in expert biathletes.
- Author
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Heinrich A, Hansen DW, Stoll O, and Cañal-Bruland R
- Subjects
- Adolescent, Adult, Female, Heart Rate, Humans, Lactic Acid blood, Male, Young Adult, Athletic Performance physiology, Fatigue physiopathology, Firearms, Fixation, Ocular, Physical Exertion, Skiing physiology
- Abstract
Objectives: Biathlon is a discipline that combines cross country skiing with rifle shooting. It demands high shooting accuracy and fast shooting times under increasing levels of physiological fatigue. Building on Vickers and Williams (2007), the current study aimed at scrutinizing the impact of physiological fatigue and gaze behavior on shooting performance in elite and sub-elite biathletes., Design: Ten members of the German national senior team (elite) and 13 members of the German national junior team (sub-elite) participated in a performance test. They conducted a roller skiing test on a treadmill including four increasing intensity levels followed by shooting blocks of five shots in both prone and standing position., Methods: Physiological measurements consisted of heart rate and blood lactate, shooting performance data included shooting accuracy and time. Eye movements were assessed, i.e. the duration of the final fixation, using a gun-mounted eye tracking system., Results: Physiological fatigue systematically increased across intensity levels. There were no differences between elite and sub-elite biathletes in percentage shooting accuracy. However, elites needed shorter shooting times than sub-elites. Both groups showed increased range times with increased workload levels in prone and standing positions. Yet, there was no effect on shooting accuracy. Finally, analyses of a subset of data did not show any effect of final fixation duration on shooting accuracy., Conclusions: Physiological fatigue seems to have no impact on shooting accuracy, but rather affects shooting times in expert biathletes. Furthermore, the duration of the final fixation does not seem to moderate shooting accuracy in elite biathletes., (Copyright © 2020 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)
- Published
- 2020
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13. 50 Years Ago in The Journal of Pediatrics: Hyperosmolality Complicating Diabetes Mellitus in Childhood.
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Hansen DW
- Subjects
- Acid-Base Imbalance etiology, Acid-Base Imbalance metabolism, Child, Diabetes Complications complications, Diabetes Complications metabolism, History, 20th Century, Humans, Acid-Base Imbalance history, Diabetes Complications history, Pediatrics history, Periodicals as Topic history
- Published
- 2019
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14. Referrals for Hypoglycemia to the Pediatric Endocrine Clinic: Is It For Real?
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Hansen DW and Eugster EA
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- Adolescent, Child, Child, Preschool, Female, Humans, Hypoglycemia diagnosis, Hypoglycemia therapy, Incidence, Male, Retrospective Studies, Ambulatory Care Facilities, Endocrinology, Hypoglycemia epidemiology, Referral and Consultation
- Published
- 2018
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15. Prevalence of Nephrocalcinosis in Pseudohypoparathyroidism: Is Screening Necessary?
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Hansen DW, Nebesio TD, DiMeglio LA, Eugster EA, and Imel EA
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- Adolescent, Child, Child, Preschool, Female, Humans, Infant, Male, Mass Screening, Nephrocalcinosis epidemiology, Prevalence, Retrospective Studies, Risk Factors, Nephrocalcinosis diagnosis, Nephrocalcinosis etiology, Pseudohypoparathyroidism complications
- Abstract
The prevalence of nephrocalcinosis in persons with pseudohypoparathyroidism has not been systematically examined. We conducted a retrospective study of renal imaging and biochemical results in 19 patients with pseudohypoparathyroidism with 49 imaging assessments. No cases of nephrocalcinosis were identified. Routine screening for nephrocalcinosis in pseudohypoparathyroidism may not be necessary., (Copyright © 2018 Elsevier Inc. All rights reserved.)
- Published
- 2018
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16. Why have microsaccades become larger? Investigating eye deformations and detection algorithms.
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Nyström M, Hansen DW, Andersson R, and Hooge I
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- Adult, Algorithms, Analysis of Variance, Humans, Male, Middle Aged, Photic Stimulation, Pupil physiology, Ocular Physiological Phenomena, Saccades physiology, Visual Perception physiology
- Abstract
The reported size of microsaccades is considerably larger today compared to the initial era of microsaccade studies during the 1950s and 1960s. We investigate whether this increase in size is related to the fact that the eye-trackers of today measure different ocular structures than the older techniques, and that the movements of these structures may differ during a microsaccade. In addition, we explore the impact such differences have on subsequent analyzes of the eye-tracker signals. In Experiment I, the movement of the pupil as well as the first and fourth Purkinje reflections were extracted from series of eye images recorded during a fixation task. Results show that the different ocular structures produce different microsaccade signatures. In Experiment II, we found that microsaccade amplitudes computed with a common detection algorithm were larger compared to those reported by two human experts. The main reason was that the overshoots were not systematically detected by the algorithm and therefore not accurately accounted for. We conclude that one reason to why the reported size of microsaccades has increased is due to the larger overshoots produced by the modern pupil-based eye-trackers compared to the systems used in the classical studies, in combination with the lack of a systematic algorithmic treatment of the overshoot. We hope that awareness of these discrepancies in microsaccade dynamics across eye structures will lead to more generally accepted definitions of microsaccades., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2016
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17. In the eye of the beholder: a survey of models for eyes and gaze.
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Hansen DW and Ji Q
- Subjects
- Humans, Regression Analysis, Eye Movement Measurements, Eye Movements physiology, Fixation, Ocular physiology, Head Movements physiology, Models, Biological
- Abstract
Despite active research and significant progress in the last 30 years, eye detection and tracking remains challenging due to the individuality of eyes, occlusion, variability in scale, location, and light conditions. Data on eye location and details of eye movements have numerous applications and are essential in face detection, biometric identification, and particular human-computer interaction tasks. This paper reviews current progress and state of the art in video-based eye detection and tracking in order to identify promising techniques as well as issues to be further addressed. We present a detailed review of recent eye models and techniques for eye detection and tracking. We also survey methods for gaze estimation and compare them based on their geometric properties and reported accuracies. This review shows that, despite their apparent simplicity, the development of a general eye detection technique involves addressing many challenges, requires further theoretical developments, and is consequently of interest to many other domains problems in computer vision and beyond.
- Published
- 2010
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18. Enhancement of 1,25-dihydroxyvitamin D3-mediated suppression of experimental autoimmune encephalomyelitis by calcitonin.
- Author
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Becklund BR, Hansen DW Jr, and Deluca HF
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- Animals, Calcitonin therapeutic use, Calcium analysis, Dose-Response Relationship, Drug, Drug Synergism, Drug Therapy, Combination, Encephalomyelitis, Autoimmune, Experimental prevention & control, Hypercalcemia, Mice, Vitamin D pharmacology, Vitamin D therapeutic use, Calcitonin pharmacology, Encephalomyelitis, Autoimmune, Experimental drug therapy, Vitamin D analogs & derivatives
- Abstract
The active form of vitamin D, 1alpha,25-dihydroxyvitamin D(3) [1,25(OH)(2)D(3)], suppresses disease development in the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis (MS). However, complete disease prevention only occurs with doses that dramatically elevate serum calcium levels, thus limiting the usefulness of 1,25(OH)(2)D(3) as a potential MS therapeutic agent. Because calcitonin (CT) is believed to be released by hypercalcemia and has been shown to be anti-inflammatory, we examined whether suppression of EAE by 1,25(OH)(2)D(3) could be mediated either in part or entirely by CT. Continuous administration of pharmacological doses of CT did not prevent EAE. However, a combination of CT and a subtherapeutic dose of 1,25(OH)(2)D(3) additively suppressed EAE without causing hypercalcemia. Moreover, CT decreased the dose of 1,25(OH)(2)D(3) required for disease suppression. Our results suggest that CT may be a significant factor but cannot account entirely for 1,25(OH)(2)D(3)-mediated suppression of EAE.
- Published
- 2009
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19. Synthesis and biological characterization of L-N(6)-(1-iminoethyl)lysine 5-tetrazole-amide, a prodrug of a selective iNOS inhibitor.
- Author
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Hallinan EA, Tsymbalov S, Dorn CR, Pitzele BS, Hansen DW Jr, Moore WM, Jerome GM, Connor JR, Branson LF, Widomski DL, Zhang Y, Currie MG, and Manning PT
- Subjects
- Acute Disease, Administration, Oral, Animals, Arthritis, Experimental pathology, Carrageenan, Chronic Disease, Crystallization, Edema chemically induced, Edema enzymology, Edema pathology, Enzyme Inhibitors chemistry, Enzyme Inhibitors metabolism, Homoarginine analogs & derivatives, Homoarginine chemistry, Homoarginine metabolism, Humans, Isoenzymes antagonists & inhibitors, Nitric Oxide Synthase Type I, Nitric Oxide Synthase Type II, Nitric Oxide Synthase Type III, Prodrugs chemistry, Prodrugs metabolism, Rats, Recombinant Proteins antagonists & inhibitors, Enzyme Inhibitors chemical synthesis, Homoarginine chemical synthesis, Lysine analogs & derivatives, Lysine chemistry, Nitric Oxide Synthase antagonists & inhibitors, Prodrugs chemical synthesis
- Abstract
The 5-tetrazole amide of L-N(6)-(1-iminoethyl)lysine (L-NIL), L-N(6)-(1-iminoethyl)lysine 5-tetrazole amide (1), has been prepared and evaluated. In contrast to L-NIL, 1 is a stable, nonhygroscopic, crystalline solid. Unlike L-NIL, 1 has minimal inhibitory activity in vitro on human inducible nitric oxide synthase (iNOS). However, it is rapidly converted in vivo to L-NIL and produces dose-dependent inhibition of iNOS in acute and chronic models of inflammation in the rodent with efficacy comparable to L-NIL. In addition, both 1 and L-NIL exhibit significant and comparable in vivo selectivity for the inhibition of iNOS vs endothelial NOS. Doses approximately 80-fold greater than those that inhibited inflammation do not elevate systemic blood pressure. In summary, both the physical properties and the pharmacological profile of 1 make it an ideal molecule for preclinical and clinical studies on the role of selective iNOS inhibitors in mediating inflammatory disease processes.
- Published
- 2002
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20. Selective heterocyclic amidine inhibitors of human inducible nitric oxide synthase.
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Moormann AE, Metz S, Toth MV, Moore WM, Jerome G, Kornmeier C, Manning P, Hansen DW Jr, Pitzele BS, and Webber RK
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- Azepines chemical synthesis, Azepines chemistry, Enzyme Inhibitors chemical synthesis, Enzyme Inhibitors chemistry, Humans, Inhibitory Concentration 50, Nitric Oxide Synthase Type II, Structure-Activity Relationship, Azepines pharmacology, Enzyme Inhibitors pharmacology, Isoenzymes antagonists & inhibitors, Nitric Oxide Synthase antagonists & inhibitors
- Abstract
The potency and selectivity of a series of 5-hetero-2-iminohexahydroazepines were examined as inhibitors of the three human NOS isoforms. The effect of ring substitution of the 5-carbon for a heteroatom is presented. Potencies (IC(50)'s) for these inhibitors are in the low micromolar range for hi-NOS with some examples exhibiting a 500x selectivity versus hec-NOS.
- Published
- 2001
- Full Text
- View/download PDF
21. 2-Iminohomopiperidinium salts as selective inhibitors of inducible nitric oxide synthase (iNOS).
- Author
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Hansen DW Jr, Peterson KB, Trivedi M, Kramer SW, Webber RK, Tjoeng FS, Moore WM, Jerome GM, Kornmeier CM, Manning PT, Connor JR, Misko TP, Currie MG, and Pitzele BS
- Subjects
- Administration, Oral, Animals, Anti-Inflammatory Agents, Non-Steroidal administration & dosage, Anti-Inflammatory Agents, Non-Steroidal chemical synthesis, Anti-Inflammatory Agents, Non-Steroidal pharmacokinetics, Azepines administration & dosage, Azepines chemical synthesis, Azepines pharmacokinetics, Biological Availability, Cell Line, Enzyme Induction drug effects, Enzyme Inhibitors administration & dosage, Enzyme Inhibitors chemical synthesis, Enzyme Inhibitors pharmacokinetics, Humans, Imines administration & dosage, Imines chemical synthesis, Imines pharmacokinetics, Inflammation blood, Inflammation chemically induced, Lipopolysaccharides toxicity, Macrophages drug effects, Macrophages enzymology, Mice, Nitric Oxide Synthase Type I, Nitric Oxide Synthase Type II, Nitric Oxide Synthase Type III, Rats, Rats, Inbred Lew, Recombinant Proteins chemical synthesis, Recombinant Proteins pharmacology, Structure-Activity Relationship, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Azepines pharmacology, Enzyme Inhibitors pharmacology, Imines pharmacology, Nitric Oxide Synthase antagonists & inhibitors
- Abstract
An attractive approach to the treatment of inflammatory conditions such as osteo- and rheumatoid arthritis, inflammatory bowel disease, and sepsis is through the selective inhibition of human inducible nitric oxide synthase (hiNOS) since localized excess nitric oxide (NO) release has been implicated in the pathology of these diseases. A series of monosubstituted iminohomopiperidinium salts possessing lipophilic functionality at ring positions 3, 5, 6, and 7 has been synthesized, and series members have demonstrated the ability to inhibit the hiNOS isoform with an IC50 as low as 160 nM (7). Compounds were found that selectively inhibit hiNOS over the human endothelial constitutive enzyme (heNOS) with a heNOS/hiNOS IC50 ratio in excess of 100 and as high as 314 (9). Potencies for inhibition of hiNOS and the human neuronal constitutive enzyme (hnNOS) are comparable. Substitution in the 3 and 7 positions provides compounds that exhibit the greatest degree of selectivity for hiNOS and hnNOS over heNOS. Submicromolar potencies for 6 and 7 in a mouse RAW cell assay demonstrated the ability of these compounds to inhibit iNOS in a cellular environment. These latter compounds were also found to be orally bioavailable and efficacious due to their ability to inhibit the increase in plasma nitrite/nitrate levels in a rat LPS model.
- Published
- 1998
- Full Text
- View/download PDF
22. Substituted 2-iminopiperidines as inhibitors of human nitric oxide synthase isoforms.
- Author
-
Webber RK, Metz S, Moore WM, Connor JR, Currie MG, Fok KF, Hagen TJ, Hansen DW Jr, Jerome GM, Manning PT, Pitzele BS, Toth MV, Trivedi M, Zupec ME, and Tjoeng FS
- Subjects
- Animals, Cerebellum enzymology, Endothelium, Vascular enzymology, Enzyme Inhibitors chemistry, Enzyme Inhibitors pharmacology, Humans, Imines chemistry, Imines pharmacology, Kinetics, Lipopolysaccharides pharmacology, Male, Molecular Structure, Neurons enzymology, Nitrates blood, Nitrites blood, Piperidines chemistry, Piperidines pharmacology, Rats, Rats, Inbred Lew, Recombinant Proteins antagonists & inhibitors, Structure-Activity Relationship, Enzyme Inhibitors chemical synthesis, Imines chemical synthesis, Isoenzymes antagonists & inhibitors, Nitric Oxide Synthase antagonists & inhibitors, Piperidines chemical synthesis
- Abstract
A series of analogues of 2-iminopiperidine have been prepared and shown to be potent inhibitors of the human nitric oxide synthase (NOS) isoforms. Methyl substitutions on the 4-position (3) or 4- and 6-positions (8) afforded the most potent analogues. These compounds exhibited IC50 values of 0.1 and 0.08 microM, respectively, for hiNOS inhibition. Substitution with cyclohexylmethyl at the 6-position (13) afforded an inhibitor that showed the best selectivity for hiNOS versus heNOS (heNOS IC50/hiNOS IC50 = 64). Following oral administration, inhibitors were found to decrease serum nitrite/nitrate levels in an in vivo rat endotoxin assay. This series of 2-iminopiperidines were prepared via the described synthetic methodologies. The effect of ring substitutions on potency and selectivity for this class of cyclic amidines as NOS inhibitors is described.
- Published
- 1998
- Full Text
- View/download PDF
23. Enkephalin analogs as systemically active antinociceptive agents: O- and N-alkylated derivatives of the dipeptide amide L-2,6-dimethyltyrosyl-N-(3-phenylpropyl)-D-alaninamide.
- Author
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Pitzele BS, Hamilton RW, Kudla KD, Tsymbalov S, Stapelfeld A, Savage MA, Clare M, Hammond DL, and Hansen DW Jr
- Subjects
- Alkylation, Amino Acid Sequence, Analgesics, Opioid metabolism, Animals, Dipeptides metabolism, Enkephalins metabolism, Male, Mice, Molecular Sequence Data, Rats, Rats, Sprague-Dawley, Receptors, Opioid metabolism, Structure-Activity Relationship, Analgesics, Opioid pharmacology, Dipeptides pharmacology, Enkephalins pharmacology
- Abstract
A number of O- and N-alkylated derivatives of the antinociceptive, orally active, mu-opioid-selective truncated enkephalin analog L-2,6-dimethyltyrosyl-N-(3-phenylpropyl)-D-alaninamide (2, SC-39566) were synthesized to explore the structure-activity relationships of the series. The parent molecule is quite forgiving of substitution on the tyrosyl phenolic moiety and on the alanyl nitrogen. The tyrosyl and (phenylpropyl)amide NH sites, however, appear to be critical to interactions with the receptor, for even modest changes at these sites cause great loss of binding potency.
- Published
- 1994
- Full Text
- View/download PDF
24. Rigid bifocal contact lenses.
- Author
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Hansen DW
- Subjects
- Humans, Patient Selection, Prosthesis Design, Prosthesis Fitting, Contact Lenses, Refractive Errors therapy
- Abstract
Rigid bifocal contact lens options continue to improve, with several new designs available in both the simultaneous and alternating vision categories. This paper reviews the selection of bifocal lens patients, describes basic lens designs, and provides guidelines for the successful fitting of rigid bifocal lenses.
- Published
- 1994
25. Systemic analgesic activity and delta-opioid selectivity in [2,6-dimethyl-Tyr1,D-Pen2,D-Pen5]enkephalin.
- Author
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Hansen DW Jr, Stapelfeld A, Savage MA, Reichman M, Hammond DL, Haaseth RC, and Mosberg HI
- Subjects
- Analgesics chemical synthesis, Analgesics metabolism, Animals, Brain metabolism, Cell Membrane metabolism, Electric Stimulation, Enkephalins chemical synthesis, Enkephalins metabolism, Male, Mice, Mice, Inbred ICR, Muscle Contraction drug effects, Pain Measurement, Receptors, Opioid, delta, Receptors, Opioid, mu, Structure-Activity Relationship, Vas Deferens drug effects, Vas Deferens physiology, Analgesia, Analgesics pharmacology, Enkephalins pharmacology, Receptors, Opioid physiology
- Abstract
The cyclic peptide [2,6-dimethyl-Tyr1,D-Pen2,D-Pen5]enkephalin (2) was synthesized by solid-phase techniques and contains the optically pure unnatural amino acid 2,6-dimethyltyrosine (DMT) as a replacement for the Tyr1 residue of [D-Pen2,D-Pen5]enkephalin (DPDPE, 1). This structural modification resulted in a 10-fold increase in the potency of 2 at the delta opioid receptor and a 35-fold increase in potency at the mu receptor while substantial delta receptor selectivity was maintained. In addition, 2 was 86-fold more effective than 1 at inhibiting electrically stimulated contractions of the mouse vas deferens. In the hot plate test, 2 was 7-fold more potent than 1 after intracerebroventricular administration in the mouse. While 1 was inactive following systemic administration of doses as high as 30 mg/kg, subcutaneous administration of 2 significantly inhibited writhing with an ED50 of 2.6 mg/kg. These results demonstrate that the potency and systemic activity of DPDPE are significantly increased by replacement of Tyr1 with DMT.
- Published
- 1992
- Full Text
- View/download PDF
26. Metabolic formation and synthesis of 1-(3-chlorophenyl)-2(4-hydroxyphenyl)-1-methyl-2(2 pyridine)ethanol. A potential hypocholesteremic agent.
- Author
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Sinsheimer JE, Van den Eeckhout E, Hewitt LE, Kido Y, Wade DR, Hansen DW Jr, Drach JC, and Burckhalter JH
- Subjects
- Animals, Cholesterol blood, Male, Pyridines pharmacology, Pyridines urine, Rats, Time Factors, Anticholesteremic Agents chemical synthesis, Pyridines chemical synthesis
- Abstract
1-(3-Chlorophenyl)-2-(4-hydroxphenyl)-1-methyl-2(2-pyridine)ethanol (8a) has been synthesized and found to be the major urinary metabolite following intraperitoneal administration of 1-(3-chlorophenyl)-1-methyl-2-phenyl-2-(2-pyridine)ethanol (1) to rats. This metabolite has a hypocholesteremic effect in rats similar to that of the parent drug.
- Published
- 1976
- Full Text
- View/download PDF
27. Acridine orange in the staining of blood parasites.
- Author
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Hansen DW, Hunter DT, Richards DF, and Allred L
- Subjects
- Animals, Dogs, Humans, Rats, Acridines, Blood microbiology, Parasites, Staining and Labeling
- Published
- 1970
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