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Pernari J, Wells LA. Poly(2-hydroxyethyl methacrylate) surface chemistry and modulus differentially modulate neutrophils and lens epithelial cells-possible implications in cellular responses to intraocular lenses. J Biomed Mater Res A 2023; 111:863-878. [PMID: 36951220 DOI: 10.1002/jbm.a.37537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 03/09/2023] [Accepted: 03/11/2023] [Indexed: 03/24/2023]
Abstract
During cataract surgery, diseased lenses in the eye are surgically removed and replaced with polymeric artificial intraocular lenses (IOLs). Patients can experience a complication called posterior capsular opacification (PCO) that is corrected through the removal of part of the posterior capsule using a neodymium: yttrium-aluminum-garnet (Nd-YAG) laser to restore the optical path. These interventions have increased costs and can damage the retina and the IOL. PCO develops when lens epithelial cells (LECs) proliferate, migrate, and undergo epithelial-to-mesenchymal transition. Neutrophils involved in the immune response triggered during implantation impact LEC behavior and produce damaging neutrophil extracellular traps (NETs). In this research, poly(2-hydroxyethyl methacrylate) (PHEMA) -based disks were synthesized with varying amounts of comonomer (HEMA with 0, 2, and 12 mol% MMA) and functionalized with carboxyl and amine groups, yielding nine different hydrogels. Material and chemical properties of the disks were characterized, and neutrophil-like HL60 cells and B3 LECs were incubated with the disks. HL60 cell behavior was more strongly influenced by chemical functionalization than by mechanical properties with increases in adherence and NET accumulation. Conversely, the behavior and viability of B3 LECs were more strongly influenced by mechanical properties with increases in cell adhesion and α-SMA expression with increasing compressive moduli. Interestingly, B3 LECs had decreased viability and increased α-SMA expression when cultured on PHEMA2 disks pretreated with isolated NETs. Critical to the understanding of PCO and its prevention are both surface chemistry and mechanics as well as the inflammatory response.
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Affiliation(s)
- J Pernari
- Department of Chemical Engineering, Queen's University, Kingston, Ontario, Canada
| | - L A Wells
- Department of Chemical Engineering, Queen's University, Kingston, Ontario, Canada
- Centre for Health Innovation, Queen's University and Kingston Health Sciences Centre, Kingston, Ontario, Canada
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Fong VM, Wells LA. Copolymer functional groups modulate extracellular trap accumulation and inflammatory markers in HL60 and murine neutrophils. Biomed Mater 2023; 18. [PMID: 36787640 DOI: 10.1088/1748-605x/acbc00] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 02/13/2023] [Indexed: 02/16/2023]
Abstract
Undesirable host responses to implants commonly lead to impaired device function. As the first immune cell to respond to inflammation, activated neutrophils release antimicrobials and neutrophil extracellular traps (NETs) that prime microenvironments for macrophages and other infiltrating cells. This research aims to understand how functional groups in copolymers of isodecyl acrylate (IDA) that are known to modulate healing in vivo, modulate neutrophil cells. Phorbol myristate acetate-activated HL60 cells and bone marrow-derived murine neutrophils (BMDN) were incubated with coatings of IDA copolymerized with, methacrylic acid (MAA films), methyl methacrylate (MM films), or MM functionalized with hexamethylenediamine (HMD films). Cells incubated on HMD films resulted in increased accumulation of NETs at the film's surface in comparison to other copolymers because of increased adhesion of HL60 onto HMD films or increased rates of NETosis from BMDN. Overall, lower inflammation was observed with cells on MAA films. HL60 cells had no increase in classical inflammatory markers such as TNF-α and ICAM-1, whereas HL60 on HMD films had increases in these same markers. Taken together, these studies give important insights into how neutrophils interact differently with functionalized copolymers and the proteins that adsorb to them, with MAA (carboxyl groups) leading to behavior associated with lower inflammation and HMD (amine groups) with higher inflammation and accumulation of NETs.
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Affiliation(s)
- Victoria M Fong
- Department of Chemical Engineering, Queen's University, 19 Division St. Room 201, Kingston, Ontario, K7L 3N6, CANADA
| | - Laura A Wells
- Department of Chemical Engineering, Queen's University, 19 Division Street Room 201, Kingston, Ontario, K7L 3N6, CANADA
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Clasky DP, Meunier L, Wells LA. Modeling the Effects of Disease, Drug Properties, and Material on Drug Transport From Intraocular Lenses. Transl Vis Sci Technol 2022; 11:14. [PMID: 35575775 PMCID: PMC9123490 DOI: 10.1167/tvst.11.5.14] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Surgically implanted intraocular lenses (IOLs) may be used as drug-delivery devices, but their effectiveness is not well defined. Computational fluid dynamics models were developed to investigate the capability of IOLs to release drugs at therapeutic concentrations. Methods Models were generated using COMSOL Multiphysics. Primary open-angle glaucoma (POAG) and wet age-related macular degeneration (AMD) were simulated by reducing aqueous vein and choroidal blood flow, respectively. Release of dexamethasone, ganciclovir, or dextran was studied using common IOL materials, polydimethylsiloxane (PDMS) and poly(2-hydroxyethyl methacrylate) (PHEMA). Results Drug clearance proceeds mainly through choroidal blood flow. When fully constricted, maximum concentration at the choroid (Cmax) values increased by 32.4% to 39,800%. Compared to dexamethasone, Cmax in different tissues decreased by 6.07% to 96.0% for ganciclovir and dextran, and clearance rates decreased by 16% to 69% for ganciclovir and by 92% to 100% for dextran. Using PDMS as the IOL reduced clearance rates by 91.3% to 94.6% compared to PHEMA. Conclusions In diseased eyes, drugs accumulate mainly in posterior tissue; thus, choroidal drug toxicity must be assessed prior to IOL implantation in POAG and AMD patients. Moreover, drug properties modulated concentration profiles in all ocular segments. The hydrophobic small-molecule dexamethasone attained the highest concentrations and cleared the fastest, whereas hydrophilic macromolecular dextran attained the lowest concentrations and cleared the slowest. Furthermore, high concentrations were achieved quickly following release from PHEMA, whereas PDMS allowed for sustained release. Translational Relevance In silico results can guide scientists and clinicians regarding important physiological and chemical factors that modulate tissue drug concentrations from drug-eluting IOLs.
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Affiliation(s)
- Danielle P Clasky
- Department of Chemical Engineering, Queen's University, Kingston, Ontario, Canada
| | - Louise Meunier
- Department of Chemical Engineering, Queen's University, Kingston, Ontario, Canada
| | - Laura A Wells
- Department of Chemical Engineering, Queen's University, Kingston, Ontario, Canada.,Centre for Health Innovation, Queen's University and Kingston Health Sciences Centre, Kingston, Ontario, Canada
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Baldwin ET, Wells LA. Hyaluronic Acid and Poly-l-Lysine Layers on Calcium Alginate Microspheres to Modulate the Release of Encapsulated FITC-Dextran. J Pharm Sci 2021; 110:2472-2478. [PMID: 33450219 DOI: 10.1016/j.xphs.2021.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 12/12/2020] [Accepted: 01/03/2021] [Indexed: 11/25/2022]
Abstract
Alginate solutions crosslink into microspheres in calcium alginate, enabling the encapsulation and subsequent release of biological macromolecules and drugs. However, release from calcium alginate into PBS is relatively fast because it will decrosslink the gel relatively quickly. In this research, FITC-dextran (MW 10 kDa) was encapsulated in 2% (w/v) calcium alginate microspheres by electrospraying. The resulting microspheres (diameter = 247 ± 13 μm) were then layered with thin polyelectrolyte films of hyaluronic acid (HA) and poly-l-lysine (PLL) to attempt to slow the diffusion of FITC-dextran out of the microspheres and the coating parameters were modified to modulate diffusion and release. Increasing the concentration of FITC-dextran encapsulated in the microspheres resulted in an increase in its release over time into PBS. Crosslinking PLL/HA layers on the microspheres did not decrease the in vitro release rates of encapsulated FITC-dextran into PBS. Increasing the number of layers on the microspheres from 3 to 5 layers significantly decreased the amount of encapsulated FITC-dextran released. However, increasing the number of layers to 7 did not further sustain the release of FITC-dextran, likely because these microspheres collapsed to a smaller size during the coating procedure, resulting in release controlled by both diffusion and swelling. Multiple layers of PLL and HA provided a robust mechanism to sustain and control release of large molecules from calcium alginate.
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Affiliation(s)
- Emily T Baldwin
- Department of Chemical Engineering, Queen's University, 99 University Ave., Kingston, Ontario, Canada
| | - Laura A Wells
- Department of Chemical Engineering, Queen's University, 99 University Ave., Kingston, Ontario, Canada.
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Wells LA, Guo H, Emili A, Sefton MV. The profile of adsorbed plasma and serum proteins on methacrylic acid copolymer beads: Effect on complement activation. Biomaterials 2017; 118:74-83. [DOI: 10.1016/j.biomaterials.2016.11.036] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 11/21/2016] [Accepted: 11/24/2016] [Indexed: 10/20/2022]
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Zhang B, Montgomery M, Chamberlain MD, Ogawa S, Korolj A, Pahnke A, Wells LA, Massé S, Kim J, Reis L, Momen A, Nunes SS, Wheeler A, Nanthakumar K, Keller G, Sefton MV, Radisic M. Biodegradable scaffold with built-in vasculature for organ-on-a-chip engineering and direct surgical anastomosis. Nat Mater 2016; 15:669-78. [PMID: 26950595 PMCID: PMC4879054 DOI: 10.1038/nmat4570] [Citation(s) in RCA: 347] [Impact Index Per Article: 43.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Accepted: 01/19/2016] [Indexed: 05/12/2023]
Abstract
We report the fabrication of a scaffold (hereafter referred to as AngioChip) that supports the assembly of parenchymal cells on a mechanically tunable matrix surrounding a perfusable, branched, three-dimensional microchannel network coated with endothelial cells. The design of AngioChip decouples the material choices for the engineered vessel network and for cell seeding in the parenchyma, enabling extensive remodelling while maintaining an open-vessel lumen. The incorporation of nanopores and micro-holes in the vessel walls enhances permeability, and permits intercellular crosstalk and extravasation of monocytes and endothelial cells on biomolecular stimulation. We also show that vascularized hepatic tissues and cardiac tissues engineered by using AngioChips process clinically relevant drugs delivered through the vasculature, and that millimetre-thick cardiac tissues can be engineered in a scalable manner. Moreover, we demonstrate that AngioChip cardiac tissues implanted with direct surgical anastomosis to the femoral vessels of rat hindlimbs establish immediate blood perfusion.
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Affiliation(s)
- Boyang Zhang
- Department of Chemical Engineering, University of Toronto, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Miles Montgomery
- Department of Chemical Engineering, University of Toronto, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - M. Dean Chamberlain
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Shinichiro Ogawa
- McEwen Center for Regenerative Medicine, Toronto, Ontario, Canada
| | - Anastasia Korolj
- Department of Chemical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Aric Pahnke
- Department of Chemical Engineering, University of Toronto, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Laura A. Wells
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Stéphane Massé
- The Toby Hull Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
| | - Jihye Kim
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Lewis Reis
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Abdulah Momen
- Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Sara S. Nunes
- Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Aaron Wheeler
- Department of Chemical Engineering, University of Toronto, Toronto, Ontario, Canada
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
| | - Kumaraswamy Nanthakumar
- The Toby Hull Cardiac Fibrillation Management Laboratory, Toronto General Hospital, Toronto, Ontario, Canada
| | - Gordon Keller
- McEwen Center for Regenerative Medicine, Toronto, Ontario, Canada
| | - Michael V. Sefton
- Department of Chemical Engineering, University of Toronto, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
| | - Milica Radisic
- Department of Chemical Engineering, University of Toronto, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- The Heart and Stroke/Richard Lewar Centre of Excellence, Toronto, Ontario, Canada
- Correspondence should be addressed to M.R. ()
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Chamberlain MD, Wells LA, Lisovsky A, Guo H, Isserlin R, Talior-Volodarsky I, Mahou R, Emili A, Sefton MV. Unbiased phosphoproteomic method identifies the initial effects of a methacrylic acid copolymer on macrophages. Proc Natl Acad Sci U S A 2015; 112:10673-8. [PMID: 26261332 PMCID: PMC4553830 DOI: 10.1073/pnas.1508826112] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
An unbiased phosphoproteomic method was used to identify biomaterial-associated changes in the phosphorylation patterns of macrophage-like cells. The phosphorylation differences between differentiated THP1 (dTHP1) cells treated for 10, 20, or 30 min with a vascular regenerative methacrylic acid (MAA) copolymer or a control methyl methacrylate (MM) copolymer were determined by MS. There were 1,470 peptides (corresponding to 729 proteins) that were differentially phosphorylated in dTHP1 cells treated with the two materials with a greater cellular response to MAA treatment. In addition to identifying pathways (such as integrin signaling and cytoskeletal arrangement) that are well known to change with cell-material interaction, previously unidentified pathways, such as apoptosis and mRNA splicing, were also discovered.
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Affiliation(s)
- Michael Dean Chamberlain
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada M5S 3G9
| | - Laura A Wells
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada M5S 3G9
| | - Alexandra Lisovsky
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada M5S 3G9
| | - Hongbo Guo
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada M5S 3G9
| | - Ruth Isserlin
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada M5S 3G9
| | - Ilana Talior-Volodarsky
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada M5S 3G9
| | - Redouan Mahou
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada M5S 3G9
| | - Andrew Emili
- Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada M5S 3G9
| | - Michael V Sefton
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, ON, Canada M5S 3G9; Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada M5S 3G9
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Wells LA, Brook MA, Sheardown H. Generic, Anthracene-Based Hydrogel Crosslinkers for Photo-controllable Drug Delivery. Macromol Biosci 2011; 11:988-98. [DOI: 10.1002/mabi.201100001] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 03/10/2011] [Indexed: 11/11/2022]
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Abstract
Ophthalmic drug delivery to the posterior segment of the eye could benefit from a responsive controlled drug delivery system with light or laser inducible changes. For example, the delivery of age-related macular degeneration drugs requires invasive monthly injections making long-term photoresponsive drug delivery a desirable option. The feasibility of this may be facilitated by both the transparency of the eye and the advanced technology in ophthalmic lasers. Hyaluronic acid photogels that are compatible with retinal pigment epithelial cell lines are shown here to deliver a variety of small and large model drugs over the long term (months). Varying UV exposures resulted in decreases/increases or the turning off and on of delivery, potentially allowing the therapy to be tailored to suit the patient and the disease.
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Affiliation(s)
- Laura A Wells
- Department of Chemical Engineering and School of Biomedical Engineering McMaster University, Hamilton, Ontario, Canada
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Abstract
Responsive polymer systems that react to thermal and light stimuli have been a focus in the biomaterials literature because they have the potential to be less invasive than currently available materials and may perform well in the in vivo environment. Natural and synthetic polymer systems created to exhibit a temperature-sensitive phase transition lead to in situ forming hydrogels that can be degradable or non-degradable. These systems typically yield physical gels whose properties can be manipulated to accommodate specific applications while requiring no additional solvents or cross-linkers. Photo-responsive isomerization, dimerization, degradation, and triggered processes that are reversible and irreversible may be used to create unique gel, micelle, liposome, and surface-modified polymer systems. Unique wavelengths induce photo-chemical reactions of polymer-bound chromophores to alter the bulk properties of polymer systems. The properties of both thermo- and photo-responsive polymer systems may be taken advantage of to control drug delivery, protein binding, and tissue scaffold architectures. Systems that respond to both thermo- and photo-stimuli will also be discussed because their multi-responsive properties hold the potential to create unique biomaterials.
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Affiliation(s)
- Laura A Wells
- Department of Chemical Engineering, McMaster University, Hamilton, Ontario, Canada
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Wells LA, Sheardown H. Extended release of high pI proteins from alginate microspheres via a novel encapsulation technique. Eur J Pharm Biopharm 2007; 65:329-35. [PMID: 17156984 DOI: 10.1016/j.ejpb.2006.10.018] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2006] [Revised: 10/13/2006] [Accepted: 10/18/2006] [Indexed: 11/30/2022]
Abstract
Alginate has potential as a matrix for controlled delivery of protein-based drugs that require site-specific long-term delivery. In the current work albumin, lysozyme and chymotrypsin were encapsulated into alginate microspheres using a novel method that involved soaking the microspheres in a protein-containing NaCl solution. This was followed by recrosslinking with calcium chloride. High pI proteins also appeared to physically crosslink the sodium alginate which resulted in more sustained release. Release was affected by the nature of the releasate solution. In TRIS buffered saline, the high pI proteins chymotrypsin and lysozyme showed sustained release lasting over 150 h. Release into 0.15% NaCl led to relatively constant release of lysozyme and chymotrypsin over more than 2000 h; reduction of the releasate volume lengthened the lysozyme release to greater than 8 months. Released lysozyme was shown to remain active for at least 16 days, in some cases with activity greater than 100% of the active control. This encapsulation technique can therefore be used to rapidly load alginate microspheres with proteins, with high isoelectric point proteins showing particular promise. Furthermore, the interactions between the high pI proteins and the alginate gel could potentially be exploited to generate new protein delivery systems.
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Affiliation(s)
- L A Wells
- Department of Chemical Engineering, McMaster University, Hamilton, Ont., Canada
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Abstract
Bulimia nervosa is a common eating disorder in adolescent women. Biological, psychological, and social factors are implicated in onset and important in treatment. Diagnosis of the syndrome, but not its subtypes, can be made well using the DSM-IV system. Screening tools, laboratory findings, and physical findings can be helpful in making the diagnosis. Comorbid disorders include affective disorders, addictive disorders, anxiety disorders, personality disorders, and anorexia nervosa. The etiology of bulimia nervosa is complex, with biologic, psychological, social, and family factors, which likely differ somewhat from patient to patient. Treatment, accordingly, should be comprehensive, individualized, and multifaceted. Many patients respond well to the use of an antidepressant, and cognitive-behavioral therapy is a useful approach for many patients. Combining these two treatments seems to be a good strategy. Environmental and family issues also need to be addressed. Many patients are treated insufficiently. More research on bulimia nervosa specific to adolescence is needed.
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Affiliation(s)
- L A Wells
- Department of Psychiatry and Psychology, Mayo Clinic, Rochester, Minnesota 55905, USA.
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Das S, Lese CM, Song M, Jensen JL, Wells LA, Barnoski BL, Roseberry JA, Camacho JM, Ledbetter DH, Schnur RE. Partial paternal uniparental disomy of chromosome 6 in an infant with neonatal diabetes, macroglossia, and craniofacial abnormalities. Am J Hum Genet 2000; 67:1586-91. [PMID: 11038325 PMCID: PMC1287936 DOI: 10.1086/316897] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2000] [Accepted: 09/27/2000] [Indexed: 11/03/2022] Open
Abstract
Neonatal diabetes, which can be transient or permanent, is defined as hyperglycemia that presents within the first month of life and requires insulin therapy. Transient neonatal diabetes mellitus has been associated with abnormalities of the paternally inherited copy of chromosome 6, including duplications of a portion of the long arm of chromosome 6 and uniparental disomy, implicating overexpression of an imprinted gene in this disorder. To date, all patients with transient neonatal diabetes mellitus and uniparental disomy have had complete paternal isodisomy. We describe a patient with neonatal diabetes, macroglossia, and craniofacial abnormalities, with partial paternal uniparental disomy of chromosome 6 involving the distal portion of 6q, from 6q24-qter. This observation demonstrates that mitotic recombination of chromosome 6 can also give rise to uniparental disomy and neonatal diabetes, a situation similar to that observed in Beckwith-Wiedemann syndrome, another imprinted disorder. This finding has clinical implications, since somatic mosaicism for uniparental disomy of chromosome 6 should also be considered in patients with transient neonatal diabetes mellitus.
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Affiliation(s)
- S Das
- Department of Human Genetics, The University of Chicago, Chicago, IL, 60637, USA.
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Abstract
Previous work (Willingham, 1999) has indicated that implicit motor sequence learning is not primarily perceptual; that is, what is learned is not a sequence of stimuli. Still other work has indicated that implicit motor sequence learning is not specific to particular muscle groups or effectors. In the present work, we tested whether implicit motor sequence learning would be represented as a sequence of response locations. In Experiment 1, learning showed very poor transfer when the response locations were changed, even though the stimulus positions were unchanged. In Experiment 2, participants switched their hand positions at transfer, so that one group of participants pushed the same sequence of keys but used a different sequence of finger movements to do so, whereas another group pushed a different sequence of keys but used the same sequence of finger movements used at training. Knowledge of the sequence was shown at transfer only if the sequence of response locations was maintained, not the sequence of finger movements.
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Affiliation(s)
- D B Willingham
- Department of Psychology, University of Virginia, Charlottesville 22903, USA.
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Affiliation(s)
- L A Wells
- Department of Psychiatry and Psychology, Mayo Clinic Rochester, Minnesota 55905, USA
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Sutor B, Wells LA, Rummans TA. Steroid-induced depressive psychosis responsive to electroconvulsive therapy. Convuls Ther 1996; 12:104-7. [PMID: 8744170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We report the case of a 15-year-old girl with acute lymphoblastic leukemia who developed a severe steroid-induced depression, which was rapidly responsive to ECT. This report adds to the growing body of literature supporting ECT as a safe and effective treatment of affective and psychotic disorders in children.
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Affiliation(s)
- B Sutor
- Department of Psychiatry, Mayo Clinic, Rochester, Minnesota 55905, USA
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Wells LA. Functional disorders in children and adolescents: diagnostic considerations. Mayo Clin Proc 1996; 71:259-65. [PMID: 8594284 DOI: 10.4065/71.3.259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE To describe the advantages of a nosologic approach to "functional" illness and its benefit in planning treatment for such illnesses. DESIGN A review of common functional syndromes occurring during childhood and adolescence in presented. RESULTS The functional versus "organic" dualism in pediatrics and family practice is not heuristic. The biopsychosocial model allows a more useful approach to nosology and treatment planning. An approach to such a clinical conceptualization is give. Several case examples are provided. CONCLUSION Patients with functional syndromes should be assessed with specific diagnostic criteria rather than criteria of exclusion.
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Affiliation(s)
- L A Wells
- Division of child and Adolescent Psychiatry, Mayo Clinic Rochester, Rochester, Minnesota 55905, USA
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Wells LA. Celestial medicine. Minn Med 1990; 73:23-4. [PMID: 2355905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- L A Wells
- Section of Child and Adolescent Psychiatry, Rochester, MN
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Abstract
Four adolescent student populations (totalling 686 girls and 705 boys) completed confidential questionnaires (98.6% response rate) concerning bulimia nervosa and alcohol abuse. All of the DSM-III-R criteria for bulimia nervosa were met by 2.0% of the girls and 0.1% of the boys. On the basis of score greater than or equal to 42 on the Adolescent Alcohol Involvement Scale, 12.5% of all girls and 9.2% of all boys were alcohol abusers. Our results suggest a significant association between bulimic behavior and alcohol abuse in this female population. Other factors associated with bulimic behavior included high maternal vocational status, high socioeconomic class (girls only), high weight for age and height, and low personal ideal weight. Other factors associated with alcohol abuse included high maternal vocational status, low paternal vocational status and education, low socioeconomic class (boys only), low grade point average, high age, and high birth order.
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Affiliation(s)
- M G Timmerman
- Mayo Medical School, Mayo Clinic, Rochester, MN 55905
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Hughes PL, Wells LA, Cunningham CJ. The dexamethasone suppression test in bulimia before and after successful treatment with desipramine. J Clin Psychiatry 1986; 47:515-7. [PMID: 3759916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Recent reports have suggested that normal-weight bulimic patients without clinical evidence of major depressive disorder will have an abnormal response to dexamethasone. Of 23 normal-weight bulimic patients without clinical evidence of major depressive disorder, 11 had abnormal results on their dexamethasone suppression tests (DSTs). This finding closely matches those of other reports. After successful treatment with desipramine, repeat DSTs showed conversion to normal suppression in 6 of the 7 patients tested. Pretreatment DST results failed to predict the response to medication. The striking similarity of these findings to those reported in patients with major depression suggests that bulimia may be a consequence or an equivalent of major affective disorder.
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Abstract
A controlled study in patients with bulimia demonstrated a significant benefit from desipramine hydrochloride treatment (91% decrease in binge frequency) in contrast to the results from a placebo (19% increase in frequency). When patients originally taking the placebo crossed over to desipramine therapy, their frequency of binges decreased 84%, so that the overall improvement was 87% fewer binges. Global clinical status improved 3.5 scales, Zung depression scores improved 8.0 points, and a bulimia symptom scale improved 14.7 points. Fifteen (68%) of 22 patients attained complete abstinence from binge eating and purging. The presence or absence of previous episodes of anorexia nervosa did not influence the treatment response. One-month follow-up data indicated persistence of the benefit attained.
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de la Fuente JR, Wells LA. Human growth hormone in psychiatric disorders. J Clin Psychiatry 1981; 42:270-4. [PMID: 7016846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The authors review some features of the neuroendocrine regulation and neuropharmacologic manipulation of human growth hormone and then discuss some of the data that suggest that this hormone system might be involved in various psychiatric disorders. While emphasis is put on alcoholism and the affective disorders, the effects of stress, psychosocial deprivation and malnutrition are briefly discussed, as well. The possibilities and limitations of the psychoendocrine approach to psychiatric illnesses as exemplified by the growth hormone system are emphasized.
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Wells LA. Family pathology and father-daughter incest: restricted psychopathy. J Clin Psychiatry 1981; 42:197-202. [PMID: 7217024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Father-daughter incest can be found in dysfunctional families of many types. The concept of restricted psychopathy is discussed and examples of this concept in relation ot incest behavior are given. Three cases of father-daughter incest are presented. Ramifications of the concept of restricted psychopathy as it applies to father-daughter incest are discussed.
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Wells LA. Rural psychiatry on the nineteenth-century frontier: the career of Jacob Bowers. Perspect Biol Med 1981; 24:270-283. [PMID: 7022353 DOI: 10.1353/pbm.1981.0030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Wells LA. William Harvey and the convergence of medicine and science. Mayo Clin Proc 1978; 53:235-45. [PMID: 345002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Wells LA. Further studies on hypothermia and the blood-brain barrier system. Cryobiology 1976; 13:80-3. [PMID: 1261295 DOI: 10.1016/0011-2240(76)90162-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Wells LA. "Why not try the experiment?" The scientific education of Edward Jenner. Proc Am Philos Soc 1974; 118:135-145. [PMID: 11615678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Wells LA. Alteration of the blood-brain barrier system by hypothermia: critical time period vs. critical temperature. Comp Biochem Physiol A Comp Physiol 1973; 44:293-6. [PMID: 4145750 DOI: 10.1016/0300-9629(73)90481-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Wells LA. Permeability of the blood-brain barrier system to rubidium in euthermia, hibernation and hypothermia. Comp Biochem Physiol A Comp Physiol 1972; 42:551-7. [PMID: 4404383 DOI: 10.1016/0300-9629(72)90133-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Wells LA. Ectopic pregnancy following hysterectomy. Can Med Assoc J 1970; 103:1301. [PMID: 5485796 PMCID: PMC1930696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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