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Johnson RM, Fraser CL. Iron Tris(bipyridine)-Centered Star Block Copolymers: Chelation of Triblock Macroligands Generated by ROP and ATRP. Macromolecules 2004. [DOI: 10.1021/ma035494+] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Uddin M, Wildman DE, Liu G, Xu W, Johnson RM, Hof PR, Kapatos G, Grossman LI, Goodman M. Sister grouping of chimpanzees and humans as revealed by genome-wide phylogenetic analysis of brain gene expression profiles. Proc Natl Acad Sci U S A 2004; 101:2957-62. [PMID: 14976249 PMCID: PMC365727 DOI: 10.1073/pnas.0308725100] [Citation(s) in RCA: 188] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Gene expression profiles from the anterior cingulate cortex (ACC) of human, chimpanzee, gorilla, and macaque samples provide clues about genetic regulatory changes in human and other catarrhine primate brains. The ACC, a cerebral neocortical region, has human-specific histological features. Physiologically, an individual's ACC displays increased activity during that individual's performance of cognitive tasks. Of approximately 45,000 probe sets on microarray chips representing transcripts of all or most human genes, approximately 16,000 were commonly detected in human ACC samples and comparable numbers, 14,000-15,000, in gorilla and chimpanzee ACC samples. Phylogenetic results obtained from gene expression profiles contradict the traditional expectation that the non-human African apes (i.e., chimpanzee and gorilla) should be more like each other than either should be like humans. Instead, the chimpanzee ACC profiles are more like the human than like the gorilla; these profiles demonstrate that chimpanzees are the sister group of humans. Moreover, for those unambiguous expression changes mapping to important biological processes and molecular functions that statistically are significantly represented in the data, the chimpanzee clade shows at least as much apparent regulatory evolution as does the human clade. Among important changes in the ancestry of both humans and chimpanzees, but to a greater extent in humans, are the up-regulated expression profiles of aerobic energy metabolism genes and neuronal function-related genes, suggesting that increased neuronal activity required increased supplies of energy.
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Johnson RM, Fraser CL. Metalloinitiation Routes to Biocompatible Poly(lactic acid) and Poly(acrylic acid) Stars with Luminescent Ruthenium Tris(bipyridine) Cores. Biomacromolecules 2004; 5:580-8. [PMID: 15003024 DOI: 10.1021/bm034421v] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Poly(lactic acid) (PLA) and poly(acrylic acid) (PAA) biomaterials with luminescent ruthenium tris(bipyridine) centers couple drug delivery and imaging functions. Hydrophobic [Ru(bpyPLA2)3](PF6)2 (1) was generated from [Ru[bpy(CH2OH)2]3](PF6)2 in bulk monomer using 4-(dimethylamino)pyridine as the catalyst. The bromoesters, [Ru[bpy(CH2OR)2]3](PF6)2, [Ru[bpy(C13H27)2][bpy(CH2OR]2](PF6)2 (4), and [Ru[bpy(PLAOR)2]3]2+ (9) (R=COCBr(CH3)2), served as initiators for tert-butyl acrylate (tBA) polymerization. Conversion of PtBA to PAA via hydrolysis affords water soluble materials, [Ru(bpyPAA2)3]2+ (7) and [Ru[bpy(C13H27)2](bpyPAA2)2]2+ (8) and the amphiphilic star polymer [Ru[bpy(PLA-PAA)2]3)](PF6)2 (11), which is soluble in a H2O/CH3CN (1:1) mixture. Luminescence excitation and emission spectra of the Ru polymers were in agreement with the parent [Ru(bpy)3]2+ chromophore (lambdaex=468, lambdaem=621 nm). Lifetimes of tau approximately 700 ns in both air and nitrogen atmospheres are typical for most materials; however, the amphiphilic star block copolymer 11 is quenched by oxygen to some degree. Thermal analysis shows the expected glass transitions for the polymeric ruthenium complex materials.
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McGee KS, Coyne-Beasley T, Johnson RM. Review of evaluations of educational approaches to promote safe storage of firearms. Inj Prev 2003; 9:108-11. [PMID: 12810734 PMCID: PMC1730973 DOI: 10.1136/ip.9.2.108] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To systematically review evaluation studies of educational interventions promoting safe firearm storage. METHODS Medline, ERIC, PsycINFO, Criminal Justice Periodicals Index, Cumulative Index of Nursing and Allied Health Literature, and Sociofile were searched. The references from each potentially eligible study were checked, and experts in the field were contacted for additional reports. In addition, an internet search was performed to identify programs not published in the conventional literature. Sources relevant to safe firearm storage promotion were selected and evaluated. RESULTS Seven studies met inclusion criteria: adult subjects, program description was included, and firearm storage outcomes were measured. One was a randomized controlled trial and the other six were one group pre-test and/or post-test. The studies were classified into the following categories based on the intervention strategies used: (1). counseling and firearm safety materials (n=3); (2). counseling/educational message (n=3); and (3). firearm safety materials distribution (n=1). The outcomes were safe firearms storage (firearms locked up and unloaded or removal from home) after intervention. Four studies, three using counseling and materials distribution, reported improved storage after the interventions. CONCLUSIONS It is not yet clear what types of interventions, or which specific intervention components, prompt gun owners to securely store their weapons. Increased understanding of gun storage behaviors and stronger evaluation designs will aid further understanding of this important issue.
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Abstract
Evolutionary approaches to the identification of DNA sequences required for transcription of the genes of the beta-globin cluster are reviewed. Sequence alignments of non-coding regions from widely divergent species revealed many conserved motifs (phylogenetic footprints) that were putative transcription factor binding sites and candidate binding proteins were identified. The differential timing of the prosimian and simian gamma-globin genes was analyzed by identifying base changes in the vicinity of the phylogenetic footprints. These differential phylogenetic footprints were shown to bind different nuclear factors, and the behavior of constructs with human or galago gamma-promoters in transgenic mice indicated that DNA motifs near the gamma-globin genes are sufficient to determine the developmental stage of expression. Locus control region alignments have identified many conserved sequence differences outside of the hypersensitive sites. Globin protein and mRNA expression profiles during embryological development in a series of catarrhine (Old World monkeys and apes) and platyrrhine (New World monkeys) primates have been determined. While all catarrhines examined to date have globin expression patterns that are highly similar to the well-established human switching behavior, platyrrhines have inactivated their gamma 1 genes by a variety of mechanisms, and have an earlier gamma-beta switch.
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Johnson RM, Goyette G, Ravindranath Y, Ho YS. Oxidation of glutathione peroxidase-deficient red cells by organic peroxides. Blood 2002; 100:1515-6. [PMID: 12184279 DOI: 10.1182/blood-2002-04-1124] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Burmeister JL, Silver JL, Al-Janabi MY, Johnson RM. Zinc(II)-catalyzed reaction of malononitrile with ethyl alcohol. Inorg Chem 2002. [DOI: 10.1021/ic50099a029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Osaki K, Mitsuda Y, Johnson RM, Schrag JL, Ferry JD. Infinite-Dilution Viscoelastic Properties of Linear and Star-Shaped Polybutadienes. Macromolecules 2002. [DOI: 10.1021/ma60025a004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Daigle DJ, Johnson RM, Sands D, Connick WJ. Surface charge properties and soil mobilities of mycoherbicidal spores. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2001; 67:617-624. [PMID: 11911629 DOI: 10.1007/s001280169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Coyne-Beasley T, Johnson RM. Law enforcement officers' opinions about gun locks: anchors on life jackets? Inj Prev 2001; 7:200-4. [PMID: 11565984 PMCID: PMC1730735 DOI: 10.1136/ip.7.3.200] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES One way law enforcement officers support firearm safety is by promoting the use of gun locks. This investigation examined law enforcement officers' willingness to use gun locks on their own guns, as well as their opinions regarding gun locks in general. SETTING Law enforcement officers from an urban agency in the southern region of the United States. METHODS Free keyed cable gun locks were distributed to all law enforcement officers in one agency who wanted one, and then an anonymous questionnaire survey was conducted about their subsequent use of, and attitudes toward, these devices. RESULTS About half of the 207 officers collected gun locks (n=103). Nearly three quarters (73%) completed and returned the questionnaire. Two thirds reported that they were not using the gun lock they collected (65%), and over half disagreed that gun lock use should be required (56%). Very few cited any actual or potential technical problems with the device. An important reason given for non-use of gun locks related to being able to access the weapon quickly in case of an emergency. CONCLUSIONS The findings highlight the need for further investigation into law enforcement officers' attitudes toward gun locks, the degree to which their attitudes affect their firearm safety counseling, and the need to develop a gun safety device that can be disengaged quickly.
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Coyne-Beasley T, Johnson RM, Charles LE, Schoenbach VJ. Firearm storage practices of officers in a law enforcement agency in the South. Am J Prev Med 2001; 21:118-23. [PMID: 11457631 DOI: 10.1016/s0749-3797(01)00327-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Law enforcement officers play an important role in promoting firearm safety. This study examined their firearm-related attitudes and practices. METHODS We conducted an anonymous, self-administered survey of law enforcement officers in an agency in the South concerning firearm ownership, storage practices, and opinions. RESULTS The 207 respondents (response rate=71%) were primarily white (60%) and male (89%). The proportions of respondents with (55%) and without (45%) children were similar. Eighty percent of the officers had firearms in addition to the one they were issued for work. Most stored firearms unlocked (59%) and loaded (68%); almost half (44%) reported storing firearms both unlocked and loaded. Eighty-five percent indicated that they felt an added need to protect themselves and family because of their job. Those who reported having firearms for self-protection were less likely than those who had firearms for recreation to store firearms securely. As compared to those without children, law enforcement officers with children were more likely to store firearms safely, and were especially likely to store firearms locked up (chi(2)=12.72, p<0.0001). Respondents favored background checks, mandatory safety training, and enforcement of storage laws. Three quarters approved of government safety regulations for handguns. CONCLUSIONS Despite the law enforcement officers' prominent role in firearm safety promotion and support for initiatives that limit unauthorized access, our study found that many do not practice safe storage. Apparently, many officers keep their firearms stored unlocked and loaded for the purpose of protecting themselves and their families. Addressing concerns about personal safety is a necessary step in promoting safe storage to law enforcement officers.
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Smith S, Johnson RM, Pepperman AB. Formulation and tillage effects on atrazine and alachlor in shallow ground water in upland corn production. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2001; 67:113-121. [PMID: 11381320 DOI: 10.1007/s001280098] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2000] [Accepted: 04/12/2001] [Indexed: 05/23/2023]
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Coyne-Beasley T, Schoenbach VJ, Johnson RM. "Love our kids, lock your guns": a community-based firearm safety counseling and gun lock distribution program. ARCHIVES OF PEDIATRICS & ADOLESCENT MEDICINE 2001; 155:659-64. [PMID: 11386952 DOI: 10.1001/archpedi.155.6.659] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Safer storage practices may reduce injury rates by limiting youth access to firearms. OBJECTIVE To determine if a firearm safety counseling and gun lock distribution program improved storage practices. DESIGN Community-based before-after trial. SETTING Urban county in central North Carolina. PARTICIPANTS One hundred twelve adult gun owners recruited through a mass media advertising campaign. INTERVENTION In the parking lot of a shopping mall, participants completed a survey, and were then provided with tailored counseling, gun safety information, a gun lock, and instructions to use it. MAIN OUTCOME MEASURES Firearm storage practices, assessed by survey and personal interview (baseline) and telephone interview (6-month follow-up). RESULTS Most participants were white (62%), men (63%), had children (58%), and owned a gun for protection (74%). At follow-up, of the 82 participants, 63 (77%) (up from 39 [48%]) reported storing their gun(s) in a locked compartment (P =.004), 59 (72%) (up from 0) reported using gun locks (P =.001), 61 (74%) (up from 57 [69%]) reported storing their ammunition locked in a separate location, 59 (72%) (up from 52 [63%]) reported storing their gun(s) unloaded, and 6 (7%) (down from 15 [18%]) reported storing firearms unlocked and loaded. Participants with children were more likely at baseline to store weapons unlocked and loaded (38 [59%] vs 19 [41%]; P =.02) but were more likely after counseling to lock their weapons (29 [58%] vs 14 [44%]) and remove guns from the home (5 [10%] vs 0 [0%]). CONCLUSIONS This program prompted reporting of safer firearm storage practices, particularly among parents. Longer follow-up, verification of self-reports and correct use, testing of gun locks, and monitoring firearm injury rates after distribution programs are needed to establish the public health potential of this approach.
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Johnson RM, Little JR, Storch GA. Kawasaki-like syndromes associated with human immunodeficiency virus infection. Clin Infect Dis 2001; 32:1628-34. [PMID: 11340536 DOI: 10.1086/320523] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2000] [Revised: 11/07/2000] [Indexed: 11/03/2022] Open
Abstract
Kawasaki disease is an acute febrile vasculitic syndrome of early childhood. It is very rarely seen in adults. Among the adult patients with Kawasaki disease who have been described, a disproportionate number are infected with human immunodeficiency virus (HIV). This suggests that the immunocompromised state may predispose individuals to this syndrome. We report our experience with 2 HIV-positive patients who presented with Kawasaki-like syndromes and review the published literature on HIV-positive patients with similar syndromes.
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Shapiro AJ, Johnson RM, Miller SF, McCarthy MC. Facial fractures in a level I trauma centre: the importance of protective devices and alcohol abuse. Injury 2001; 32:353-6. [PMID: 11382418 DOI: 10.1016/s0020-1383(00)00245-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Urban trauma centres have recently noted a shift in the causative mechanism of facial fractures away from motor vehicle crashes (MVC) to blunt assaults (BA). This study was conducted to examine the incidence and aetiology of facial fractures at our institution as well as the relationship with alcohol and protective device use. Trauma registry records of all patients admitted to a level I trauma centre from 1 January 1988 to 1 January 1999 were reviewed. There were 13594 trauma admissions during the 11-year period. Facial fractures were sustained by 1429 patients (10.5%) and this group forms the subject of this study. MVC was the predominant aetiology (59.9%) followed by BA (18.8%). Facial fractures were found in 9.5% of restrained MVC patients compared to 15.4% of unrestrained patients (P<0.00l). Non-helmeted motorcyclists were four times more likely to sustain facial fractures (4.3% vs. 18.4%) than helmeted patients (P<0.00l). 39.6% of patients in the MVC group were legally intoxicated compared to 73.5% in the BA group (P<0.00l). 45.4% of unrestrained patients with facial fractures were intoxicated compared to 11.8% of restrained MVC patients with facial fractures (P<0.001). MVC continue to be the primary aetiology of facial fractures in our trauma population. Protective devices decrease the incidence of facial fractures. Lack of protective device use and the consumption of alcohol correlate with sustaining facial fractures.
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Abstract
This study was undertaken because there is a dearth of objective information in the literature on the clinical instability of the cervical spine below C2. To our knowledge, it is the first biomechanical investigation designed to analyze clinical stability. We have carried out a quantitative analysis of the behavior of the spine as a function of the systematic destruction of various anatomic elements. Under controlled conditions designed to maintain the biological integrity of the specimens, 17 motion segments from 8 cervical spines were analyzed. The spines were studied with either flexion or extension simulated using physiologic loads. Some of the more important findings are: (1) In sectioning the ligaments, one observes small increments of change followed without warning by sudden, complete disruption of the spine; (2) Removal of the facets alters the motion segment such that in flexion, there is less angular displacement and more horizontal displacement; (3) The anterior ligaments contribute more to stability in extension than the posterior ligaments and in flexion, the converse is true; (4) The adult cervical spine is unstable, or on the brink of instability, when any of the following conditions are present: a) All the anterior or all the posterior elements are destroyed or unable to function. b) More than 3.5 mm horizontal displacement of one vertebra in relation to an adjacent vertebra measured on lateral roentgenograms (resting or flexion-extension). c) More than 11 degrees of rotation difference to that of either adjacent vertebra measured on a resting lateral or flexion-extension roentgenogram. These findings can be aptly applied to clinical situations and when instability as determined by the above criteria is present, surgical fusion or some other method to achieve stability should be seriously considered. Work is continuing on this problem as we do not consider this to be altogether complete or definitive. Hopefully, this initial study will stimulate further scientific and clinical investigations.
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Johnson RM, Buck S, Chiu CH, Gage DA, Shen TL, Hendrickx AG, Gumucio DL, Goodman M. Humans and old world monkeys have similar patterns of fetal globin expression. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 2000; 288:318-26. [PMID: 11144280 DOI: 10.1002/1097-010x(20001215)288:4<318::aid-jez4>3.0.co;2-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The expression of epsilon- and gamma-globin mRNA and protein has been determined in three Old World monkey species (Macaca mulatta, Macaca nemestrina, and Cercopithecus aethiops). Using RT-PCR with primers for epsilon- and gamma-globin, both mRNAs were detected in early fetal stages, whereas at 128 days (85% of full term), only gamma was expressed. High-performance liquid chromatography was used for separation and quantitation, and matrix-assisted laser desorption/ionization mass spectrometry was used for identification of globin polypeptides. An alpha-globin polymorphism was observed in all of the species examined. During fetal life, gamma-globin was the predominant expressed beta-type globin. The red blood cells of infants still contained substantial amounts of gamma-globin, which declined to negligible levels in 14 weeks as beta-globin expression reached adult values. The ratio of gamma1- to gamma2-globins (equivalent to Ggamma/Agamma in humans) was approximately 2.5, similar to the Ggamma/Agamma ratio observed in humans. Thus, gamma-globin gene expression in these Old World monkeys species has three features in common with human expression: expression of both duplicated gamma genes, the relative preponderance of gamma1 over gamma2 expression, and the delay of the switch from gamma- to beta-globin until the perinatal period. Thus, the catarrhines seem to share a common pattern of developmental switching in the beta-globin gene cluster, which is distinct from the timing of expression in either prosimians or the New World monkeys. Our results indicate that an Old World monkey, such as Rhesus, could serve as a model organism (resembling humans) for experimentally investigating globin gene expression patterns during the embryonic, fetal, and postnatal stages.
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Richard R, Miller S, Staley M, Johnson RM. Multimodal versus progressive treatment techniques to correct burn scar contractures. THE JOURNAL OF BURN CARE & REHABILITATION 2000; 21:506-12. [PMID: 11194803 DOI: 10.1097/00004630-200021060-00006] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The treatment of burn scar contractures is a major emphasis in the rehabilitation of patients with burn injuries. Many treatment techniques have been used successfully but without a critical investigation of the best practice of care. In this study, we compared the outcomes for pediatric and adult patients treated with a multimodal therapy approach to treatment techniques that are considered to be progressive to determine if differences existed in the techniques. The medical records of 52 patients with documented burn scar contractures were reviewed for patient and rehabilitation treatment parameters. Included were population demographic information and type of treatment intervention used to correct the scar contracture. In particular, the postburn day when the contracture appeared, the percentage of range of motion deficit, the day when definitive treatment that eventually corrected the contracture was begun, and the days required to correct the contracture were noted. With equal range-of-motion deficits identified, the burn scar contractures of patients in the progressive treatment group were corrected in less than half the time of the burn scar contractures of the patients in the multimodal treatment group. This result occurred despite scar contractures that appeared significantly earlier and later initiation of definitive treatment.
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Johnson RM, Ng C, Samson CCM, Fraser CL. Copper ATRP Catalysts with Quadridentate Amine Ligands: The Effects of Steric and Electronic Tuning on the Polymerization of Methyl Methacrylate. Macromolecules 2000. [DOI: 10.1021/ma9911905] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Johnson RM, Goyette G, Ravindranath Y, Ho YS. Red cells from glutathione peroxidase-1-deficient mice have nearly normal defenses against exogenous peroxides. Blood 2000; 96:1985-8. [PMID: 10961904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
The role of glutathione peroxidase in red cell anti-oxidant defense was examined using erythrocytes from mice with a genetically engineered disruption of the glutathione peroxidase-1 (GSHPx-1) gene. Because GSHPx-1 is the sole glutathione peroxidase in the erythrocyte, all red cell GSH peroxidase activity was eliminated. Oxidation of hemoglobin and membrane lipids, using the cis-parinaric acid assay, was determined during oxidant challenge from cumene hydroperoxide and H(2)O(2). No difference was detected between wild-type red cells and GSHPx-1-deficient cells, even at high H(2)O(2) exposures. Thus, GSHPx-1 appears to play little or no role in the defense of the erythrocyte against exposure to peroxide. Simultaneous exposure to an H(2)O(2) flux and the catalase inhibitor 3-amino-1,2,4-triazole supported this conclusion. Hemoglobin oxidation occurred only when catalase was depleted. Circulating erythrocytes from the GSHPx-1-deficient mice exhibited a slight reduction in membrane thiols, indicating that high exposure to peroxides might occur naturally in the circulation. (Blood. 2000;96:1985-1988)
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Abstract
Mood and behavior changes that have a seasonal pattern were first called seasonal affective disorder (SAD) in 1984. SAD, which affects about 5% of Americans, is most common among reproductive-age women. Afflicted patients typically experience debilitating somatic complaints of fatigue, discomfort, lethargy and atypical depressive complaints of hypersomnia, increased appetite, carbohydrate craving, and weight gain. This article presents current issues in the clinical assessment and management of SAD.
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Johnson RM. Balancing a large scale of responsibility: an interview with R. Milton Johnson. HEALTHCARE FINANCIAL MANAGEMENT : JOURNAL OF THE HEALTHCARE FINANCIAL MANAGEMENT ASSOCIATION 2000; 54:33-4. [PMID: 11010179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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Woodcock RJ, Marx WF, Johnson RM, Lowe JM, Lipper MH, Kallmes DF. Needle diameter in outpatient myelography: rates of adverse effects and current practice trends. Neuroradiology 2000; 42:371-4. [PMID: 10872160 DOI: 10.1007/s002340050902] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Telephone calls were made to 1251 consecutive patients one day following outpatient myelography. Data were available on 518 patients punctured with 22-gauge (g) (large-diameter) and 465 with 25-g (small-diameter) spinal needles. We surveyed 48 academic and private practice groups regarding needle diameter use in myelography; data were obtained from 34 private practice and 14 academic radiology departments. Patients reported adverse effects including mild and severe headache, back pain and nausea. The percentage of total adverse effects was significantly greater in the 22-g than in the 25-g needle group. The percentage of patients with headache was higher in the 22-g than in the 25-g group, but this difference was not statistically significant. Only 19% of private practice groups and 17% of academic centers use 25-g needles; the remainder use 20-g or 22-g needles.
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Raymon HK, Thode S, Zhou J, Friedman GC, Pardinas JR, Barrere C, Johnson RM, Sah DW. Immortalized human dorsal root ganglion cells differentiate into neurons with nociceptive properties. J Neurosci 1999; 19:5420-8. [PMID: 10377351 PMCID: PMC6782307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
A renewable source of human sensory neurons would greatly facilitate basic research and drug development. We had established previously conditionally immortalized human CNS cell lines that can differentiate into functional neurons (). We report here the development of an immortalized human dorsal root ganglion (DRG) clonal cell line, HD10.6, with a tetracycline-regulatable v-myc oncogene. In the proliferative condition, HD10.6 cells have a doubling time of 1.2 d and exhibit a neuronal precursor morphology. After differentiation of clone HD10.6 for 7 d in the presence of tetracycline, v-myc expression was suppressed, and >50% of the cells exhibited typical neuronal morphology, stained positively for neuronal cytoskeletal markers, and fired action potentials in response to current injection. Furthermore, this cell line was fate-restricted to a neuronal phenotype; even in culture conditions that promote Schwann cell or smooth muscle differentiation of neural crest stem cells, HD10.6 differentiated exclusively into neurons. Moreover, differentiated HD10.6 cells expressed sensory neuron-associated transcription factors and exhibited capsaicin sensitivity. Taken together, these data indicate that we have established an immortalized human DRG cell line that can differentiate into sensory neurons with nociceptive properties. The cell line HD10.6 represents the first example of a human sensory neuronal line and will be valuable for basic research, as well as for the discovery of novel drug targets and clinical candidates.
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Baecker PA, Lee WH, Verity AN, Eglen RM, Johnson RM. Characterization of a promoter for the human glial cell line-derived neurotrophic factor gene. BRAIN RESEARCH. MOLECULAR BRAIN RESEARCH 1999; 69:209-22. [PMID: 10366742 DOI: 10.1016/s0169-328x(99)00106-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
To address the regulation of glial cell line-derived neurotrophic factor (GDNF) gene expression, we have isolated 5' extended cDNAs, cloned the human GDNF gene, and characterized the promoter. GDNF-encoding 5' extended cDNAs containing a novel exon were isolated via reverse transcription-polymerase chain reaction (RT-PCR) of mRNA from human fetal kidney and adult skeletal muscle. The GDNF gene was isolated from a human genomic library in a P1 bacteriophage vector. Analysis of the 5' flanking sequence revealed a promoter that lacks a CCAAT-box motif and is GC rich. Consensus binding sites for a variety of transcription factors have been identified in the promoter. Promoter/reporter plasmids have been constructed by fusion of the promoter and a portion of exon I to a luciferase gene. The promoter/reporter construct and a number of promoter deletions were transiently transfected into two human cell lines known to express GDNF. Multiple enhancer and silencer regions were revealed as well as a minimal promoter sufficient for basal transcription. Finally, a RT-PCR assay, specific for transcripts originating from this GDNF promoter, was developed and used to show that this promoter is active in vivo. The results suggest GDNF is regulated in a complex manner.
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Vitello W, Kim M, Johnson RM, Miller S. Full-thickness burn to the hand from an automobile airbag. THE JOURNAL OF BURN CARE & REHABILITATION 1999; 20:212-5. [PMID: 10342473 DOI: 10.1097/00004630-199905000-00009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
An 18-year-old male was involved in a single car motor vehicle accident in which the driver's side airbag was deployed. He presented to the trauma center with complex injuries to the left hand, lacerations to the scalp, and a full-thickness burn to the ulnar aspect of the right hand that included the hypothenar area and the fifth digit. The patient was admitted to the trauma center and received immediate consultation from the burn service. He underwent debridement and split-thickness skin grafting of 50 cm2 of the right hand on postburn day 3. The graft became necrotic and the patient underwent debridement of the skin and the abductor minimi muscle of the right hand on postburn day 32. Split-thickness skin grafting and release of flexion contracture were successfully completed 18 days later. The police and fire departments reported that the airbag showed signs of thermal destruction. Upon request, Honda motors submitted information from the TRW safety systems and material safety data sheet (Mesa, Ariz, issued 1989) that showed that airbag canisters contain the chemicals sodium azide and cupric oxide. Water may react with sodium azide to form highly toxic and explosive hyfrazoic acid. These chemicals are converted to sodium hydroxide, which can cause significant chemical burns. In addition, these chemicals may ignite when exposed to live electrical wires or temperatures greater than 300 degrees F. We conclude that burns associated with damaged deployed airbags in motor vehicle accidents may be the results of both chemical and thermal injury. The extent of the burn wound may be underestimated, as our case illustrates. Full-thickness burns resulting from airbag deployment may require more aggressive initial debridement and treatment.
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Richard R, DerSarkisian D, Miller SF, Johnson RM, Staley M. Directional variance in skin movement. THE JOURNAL OF BURN CARE & REHABILITATION 1999; 20:259-64. [PMID: 10342482 DOI: 10.1097/00004630-199905000-00018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Skin tension is known to affect the amount of movement in normal skin and has been theorized to have a possible influence on burn scars. This study measured the directional variance in skin movement, which is related to this theory. Twenty adult female volunteers had 5 predetermined skin sites tested; these sites were on the ventral surface of the upper extremities (UE), from the shoulder to the wrist. A 1 kg axial traction force was randomly applied to each skin site in both proximal and distal directions. The skin was load-cycled 6 times before movement was measured with the use of a laser beam projection. Analysis was performed for each site, and pooled data was normalized for the entire UE. Distal skin movement was significantly greater than proximal movement at each of the 5 test sites and for the UE as a whole (P < .001). No significant differences were found among like-direction sites. Only subject height and length of UE correlated strongly (r = .88). This study demonstrates a difference in skin movement and discusses how these findings may relate to the theory that skin tension could be involved in burn scar contracture and hypertrophy.
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Jett MF, Ramesha CS, Brown CD, Chiu S, Emmett C, Voronin T, Sun T, O'Yang C, Hunter JC, Eglen RM, Johnson RM. Characterization of the analgesic and anti-inflammatory activities of ketorolac and its enantiomers in the rat. J Pharmacol Exp Ther 1999; 288:1288-97. [PMID: 10027870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
The marked analgesic efficacy of ketorolac in humans, relative to other nonsteroidal anti-inflammatory drugs (NSAIDs), has lead to speculation as to whether additional non-NSAID mechanism(s) contribute to its analgesic actions. To evaluate this possibility, we characterized (R,S)-ketorolac's pharmacological properties in vivo and in vitro using the nonselective cyclooxygenase (COX) inhibitors [indomethacin (INDO) and diclofenac sodium (DS)] as well as the selective COX-2 inhibitor, celecoxib, as references. The potency of racemic (R,S)-ketorolac was similar in tests of acetic acid-induced writhing, carrageenan-induced paw hyperalgesia, and carrageenan-induced edema formation in rats; ID50 values = 0.24, 0. 29, and 0.08 mg/kg, respectively. (R,S)-ketorolac's actions were stereospecific, with (S)-ketorolac possessing the biological activity of the racemate in the above tests. The analgesic potencies for (R,S)-, (S)-, and (R)-ketorolac, INDO, and DS were highly correlated with their anti-inflammatory potencies, suggesting a common mechanism. (R,S)-ketorolac was significantly more potent than INDO or DS in vivo. Neither difference in relative potency of COX inhibition for (R,S)-ketorolac over INDO and DS nor activity of (S)-ketorolac at a number of other enzymes, channels, or receptors could account for the differences in observed potency. The distribution coefficient for (R,S)-ketorolac was approximately 30-fold less than for DS or INDO, indicating that (R,S)-ketorolac is much less lipophilic than these NSAIDs. Therefore, the physicochemical and pharmacokinetics properties of (R,S)-ketorolac may optimize the concentrations of (S)-ketorolac at its biological target(s), resulting in greater efficacy and potency in vivo.
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Fowler CJ, Janson U, Johnson RM, Wahlström G, Stenström A, Norström K, Tiger G. Inhibition of anandamide hydrolysis by the enantiomers of ibuprofen, ketorolac, and flurbiprofen. Arch Biochem Biophys 1999; 362:191-6. [PMID: 9989926 DOI: 10.1006/abbi.1998.1025] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The endogenous cannabimimetic anandamide is hydrolyzed by a fatty acid amide hydrolase to yield arachidonic acid and ethanolamine. In the present study, the regional distribution of the activity and its sensitivity to inhibition by the enantiomers of ibuprofen, ketorolac, and flurbiprofen has been investigated. The rate of [3H]anandamide hydrolysis was found in both 7-week-old and 90-week-old rats to be in the order hippocampus > cerebral cortex > cerebellum > striatum approximately midbrain, with higher rates of hydrolysis for the 7-week-old rats than for the 90-week-old rats. In whole brain (minus cerebellum), the R(-)-enantiomer of ibuprofen was a mixed-type inhibitor of anandamide hydrolysis and was approximately 2-3 times more potent than the S(+)-enantiomer, IC50 values of 230 and 750 microM, respectively, being found. A similar pattern of inhibition of anandamide hydrolysis was seen when intact C6 rat glioma cells were used. Ketorolac inhibited rat brain anandamide hydrolysis, with IC50 values of 50, 440, and 80 microM being found for the R-, S-, and R,S-forms, respectively. The IC50 value for R-flurbiprofen (60 microM) was similar to the IC50 value for the S-enantiomer (50 microM). These data demonstrate that there is no dramatic enantiomeric selectivity of NSAID compounds as inhibitors of fatty acid amide hydrolase enzyme(s) responsible for the hydrolysis of anandamide. The enantiomers of flurbiprofen and R-ketorolac are the most potent NSAID inhibitors of fatty acid amide hydrolase yet reported.
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Verity AN, Wyatt TL, Lee W, Hajos B, Baecker PA, Eglen RM, Johnson RM. Differential regulation of glial cell line-derived neurotrophic factor (GDNF) expression in human neuroblastoma and glioblastoma cell lines. J Neurosci Res 1999; 55:187-97. [PMID: 9972821 DOI: 10.1002/(sici)1097-4547(19990115)55:2<187::aid-jnr6>3.0.co;2-t] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Human SK-N-AS neuroblastoma and U-87MG glioblastoma cell lines were found to secrete relatively high levels of glial cell line-derived neurotrophic factor (GDNF). In response to growth factors, cytokines, and pharmacophores, the two cell lines differentially regulated GDNF release. A 24-hr exposure to tumor necrosis factor-alpha (TNFalpha; 10 ng/ml) or interleukin-1beta (IL-1,; 10 ng/ml) induced GDNF release in U-87MG cells, but repressed GDNF release from SK-N-AS cells. Fibroblast growth factors (FGF)-1, -2, and -9 (50 ng/ml), the prostaglandins PGA2, PGE2, and PGI2 (10 microM), phorbol 12,13-didecanoate (PDD; 10 nM), okadaic acid (10 nM), dexamethasone (1 microM), and vitamin D3 (1 microm) also differentially effected GDNF release from U-87MG and SK-N-AS cells. A result shared by both cell lines, was a two- to threefold increase in GDNF release by db-cAMP (1 mM), or forskolin (10 microM). In general, analysis of steady-state GDNF mRNA levels correlated with changes in extracellular GDNF levels in U-87MG cells but remained static in SK-N-AS cells. The data suggest that human GDNF synthesis/release can be regulated by numerous factors, signaling through multiple and diverse secondary messenger systems. Furthermore, we provide evidence of differential regulation of human GDNF synthesis/release in cells of glial (U-87MG) and neuronal (SK-N-AS) origin.
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Johnson RM, Panchoosingh H, Goyette G, Ravindranath Y. Increased erythrocyte deformability in fetal erythropoiesis and in erythrocytes deficient in glucose-6-phosphate dehydrogenase and other glycolytic enzymes. Pediatr Res 1999; 45:106-13. [PMID: 9890617 DOI: 10.1203/00006450-199901000-00018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Erythrocyte deformability was determined in more than 500 clinical samples, and was found to be elevated in conditions in which fetal-like red cells are produced: aplastic anemia (3/3 cases), myelodysplastic syndromes, polycythemias, sickle cell anemia during treatment with hydroxyurea, paroxysmal nocturnal hemoglobinuria, and recovery from B12 deficiency. Elevated deformability was observed in neonatal erythrocytes, and during recovery from transient erythroblastopenia of childhood, when fetal-like red cells are known to be produced. Increased deformability appears to be a feature of fetal and fetal-like red cells. Forty-eight cases of enzymatically verified glucose-6-phosphate (G-6-PD) deficiency were also examined. Thirty out of 32 G-6-PD(A-) individuals, including both heterozygotes and hemizygotes, exhibited increased deformability during the steady state. In contrast, G-6-PD(Med) hemizygotes had normal deformability. Increased deformability was also found in G-6-PD(Huron) (n=3), G-6-PD(Wayne) (n=4), triose phosphate isomerase deficiency (n=2), and pyruvate kinase deficiency (n=2). An elevated osmoscan was found in more than 90% of female G-6-PD heterozygotes, affording a simple screening test for heterozygotes. Deformability remained high during hemolytic episodes, when older enzyme deficient cells are removed from the circulation. In four cases of G-6-PD deficiency with normal deformability, evidence for co-existing hereditary spherocytosis was found. The combination of conditions with opposing effects on deformability resulted in nearly normal deformability. Because increased red cell deformability is a feature of fetal erythrocytes, these results suggest that the red cells in many cases of glycolytic enzyme deficiency are fetal-like.
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Kahle PJ, Shooter EM, Johnson RM, Verity AN. Phosphatidylcholine-specific phospholipase inhibitor D609 differentially affects MAP kinases and immediate-early genes in PC12 cells. Cell Signal 1998; 10:321-30. [PMID: 9692675 DOI: 10.1016/s0898-6568(98)00010-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The effects of tricyclodecan-9-yl xanthogenate (D609), an inhibitor of phosphatidylcholine-specific phospholipases, on PC12 cells were investigated. D609 repressed nerve growth factor (NGF)-mediated induction of c-fos mRNA with an IC50 approximately 50 microg/ml. Interestingly, maximal c-fos-suppressing doses of D609 did not affect activity of extracellular signal-regulated kinases. Surprisingly, D609 enhanced the extracellular acidification rate of PC12 cells, even in the absence of NGF. D609 alone induced c-jun mRNA with the same potency as it repressed the NGF-induced expression of c-fos. Like NGF, D609 alone induced c-jun even in the presence of dominant-negative Ras. Immediate-early induction of c-jun mRNA by NGF and D609 was abrogated by pretreatment with the kinase inhibitor olomoucine. Jun kinase, which is inhibited by olomoucine, was found to be activated by D609. Thus, D609 might induce c-jun in PC12 cells as a consequence of Jun kinase activation through a Ras-independent pathway. Under the same conditions, D609 repressed NGF-mediated induction of c-fos mRNA.
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Verity AN, Wyatt TL, Hajos B, Eglen RM, Baecker PA, Johnson RM. Regulation of glial cell line-derived neurotrophic factor release from rat C6 glioblastoma cells. J Neurochem 1998; 70:531-9. [PMID: 9453547 DOI: 10.1046/j.1471-4159.1998.70020531.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
We have monitored glial cell line-derived neurotrophic factor (GDNF) secretion from rat C6 glioblastoma cells by ELISA. Representative cytokines, neurotrophins, growth factors, neuropeptides, and pharmacological agents were tested for their ability to modulate GDNF release. Whereas most factors tested had minimal effect, a 24-h treatment with fibroblast growth factor-1, -2, or -9 elevated secreted GDNF protein levels five- to 10-fold. The proinflammatory cytokines interleukin-1beta, interleukin-6, tumor necrosis factor-alpha, and lipopolysaccharide elevated GDNF release 1.5- to twofold. Parallel studies aimed at elucidating intracellular events that may regulate GDNF synthesis/release demonstrated the involvement of multiple signaling pathways. GDNF levels were increased by phorbol 12,13-didecanoate (10 nM) activation of protein kinase C, the Ca2+ ionophore A23187 (1 microM), okadaic acid (10 nM) inhibition of type-2A protein phosphatases, nitric oxide donors (1 mM), and H2O2 (1 mM)-induced oxidative stress. Elevation of cyclic AMP levels by either forskolin (10 microM) or dibutyryl cyclic AMP (1 mM) repressed GDNF secretion, as did treatment with the glucocorticoid dexamethasone (1 microM). Our results demonstrate that diverse biological factors are capable of modulating GDNF protein levels and that multiple signal transduction systems can regulate GDNF synthesis and/or release.
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Cooper JB, Pang S, Albin S, Zheng J, Johnson RM. Fabrication of Boron-Doped CVD Diamond Microelectrodes. Anal Chem 1998; 70:464-7. [DOI: 10.1021/ac970762l] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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87
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Johnson RM. The TRAM flap for breast reconstruction. Plast Reconstr Surg 1997; 99:2111-3. [PMID: 9180751 DOI: 10.1097/00006534-199706000-00066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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88
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Day-Lollini PA, Stewart GR, Taylor MJ, Johnson RM, Chellman GJ. Hyperplastic changes within the leptomeninges of the rat and monkey in response to chronic intracerebroventricular infusion of nerve growth factor. Exp Neurol 1997; 145:24-37. [PMID: 9184106 DOI: 10.1006/exnr.1997.6448] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Recombinant human nerve growth factor (rhNGF) was delivered for up to 6 months by continuous intracerebroventricular (i.c.v.) infusion to CD (Sprague-Dawley derived) rats and cynomolgus monkeys. Rats (n = 15/sex/group) received doses of 0 (vehicle), 6, 60, or 300 ng/day; monkeys (n = 5/sex/group) received 0, 0.6, 6, or 60 microg/day of rhNGF. Animals tolerated i.c.v. infusion with no behavioral signs attributable to rhNGF. Body weight was transiently decreased in female rats at the highest dose. At the completion of dosing, histological examination in both species revealed an increase in the thickness of the leptomeninges along the ventral and lateral surfaces of the hindbrain and extending over the dorsal aspect of the spinal cord. The change was present to varying degrees at all doses of rhNGF and tended to be more severe at higher doses. At the light microscopic level, the leptomeninges contained layers of well-differentiated, spindle-shaped cells and a plexus of axonal fibers. Cells were immunoreactive for S-100 protein and were associated with an accumulation of Type IV collagen, suggesting Schwann cell origin. Electron microscopy revealed numerous fine caliber axons ensheathed by the presumptive Schwann cells, with myelination of individual axonal segments. These findings suggest that chronic i.c.v. delivery of rhNGF has stimulated axonal sprouting and secondary hyperplasia of Schwann or Schwann-like support cells within the pia-arachnoid.
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Emmett CJ, McNeeley PA, Johnson RM. Evaluation of human astrocytoma and glioblastoma cell lines for nerve growth factor release. Neurochem Int 1997; 30:465-74. [PMID: 9106262 DOI: 10.1016/s0197-0186(96)00083-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Nerve growth factor (NGF) prevents degeneration of cholinergic neurons in the central nervous system (CNS), and has potential as a therapeutic treatment for Alzheimer's disease. The inability of NGF to cross the blood-brain barrier has prompted pharmacological approaches investigating peripherally administered compounds that stimulate release of endogenous NGF. This study describes the NGF-releasing properties of six human astrocytoma and glioblastoma cell lines (SW 1088, SW 1783 and CRL 1718 astrocytomas, and U-138, U-373, and T98G glioblastomas). Using a highly specific two-site ELISA for human NGF, basal NGF release could be detected in all cell lines, with the lowest level in the T98G line (approximately 80 pg NGF/ml). Cell lines tested with a variety of compounds for 24 h in serum-free media demonstrated stimulation of NGF release by distinct mechanisms. NGF levels were markedly elevated (up to 8-fold above vehicle-treated cells) when stimulated with the cytokine interleukin-1 beta (IL-1 beta). Phorbol ester stimulated NGF release 4-fold. Clenbuterol, 4-methyl catechol, and propentofylline had little activity, while 6-(4-hydroxybutyl)-2,3,5,-trimethyl-1,4,benzoquinone (TMQ), dexamethasone and 1,25-dihydroxyvitamin D3 elevated NGF levels 3-fold. These data indicate differences in the ability of human astrocytoma and glioblastoma cells to release NGF when stimulated with mechanistically distinct compounds.
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Johnson RM, Buck S, Schneider H, Sampaio I, Gage DA, Shen TL, Schneider MP, Goodman M. Identification of pre-gamma-globin. Hemoglobin 1997; 21:143-53. [PMID: 9101283 DOI: 10.3109/03630269708997518] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
A pre-gamma-globin species was identified by high performance liquid chromatography in platyrrhine primates. Although pre-gamma-globin has not been observed in human hemoglobin, its identification in platyrrhine hemoglobin was facilitated by the functional inactivation of one of the duplicated gamma-globin genes in platyrrhines, which simplified the high performance liquid chromatography elution pattern. Part, but not all, of the pre-gamma was glutathionyl gamma 2-globin, and matrix-assisted laser desorption/ionization mass spectrometry was used to demonstrate that the glutathionyl residue was located on cysteine 93. As this residue is invariant in primates, it is predicted that the formation of glutathionyl gamma-globin will be seen in all primate hemoglobins under appropriate conditions.
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Johnson RM, Buck S, Chiu C, Schneider H, Sampaio I, Gage DA, Shen TL, Schneider MP, Muniz JA, Gumucio DL, Goodman M. Fetal globin expression in New World monkeys. J Biol Chem 1996; 271:30298. [PMID: 8991898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
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92
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Holtzman DM, Santucci D, Kilbridge J, Chua-Couzens J, Fontana DJ, Daniels SE, Johnson RM, Chen K, Sun Y, Carlson E, Alleva E, Epstein CJ, Mobley WC. Developmental abnormalities and age-related neurodegeneration in a mouse model of Down syndrome. Proc Natl Acad Sci U S A 1996; 93:13333-8. [PMID: 8917591 PMCID: PMC24093 DOI: 10.1073/pnas.93.23.13333] [Citation(s) in RCA: 349] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
To study the pathogenesis of central nervous system abnormalities in Down syndrome (DS), we have analyzed a new genetic model of DS, the partial trisomy 16 (Ts65Dn) mouse. Ts65Dn mice have an extra copy of the distal aspect of mouse chromosome 16, a segment homologous to human chromosome 21 that contains much of the genetic material responsible for the DS phenotype. Ts65Dn mice show developmental delay during the postnatal period as well as abnormal behaviors in both young and adult animals that may be analogous to mental retardation. Though the Ts65Dn brain is normal on gross examination, there is age-related degeneration of septohippocampal cholinergic neurons and astrocytic hypertrophy, markers of the Alzheimer disease pathology that is present in elderly DS individuals. These findings suggest that Ts65Dn mice may be used to study certain developmental and degenerative abnormalities in the DS brain.
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Johnson RM, Buck S, Chiu CH, Schneider H, Sampaio I, Gage DA, Shen TL, Schneider MPC, Muniz JA, Gumucio DL, Goodman M. Fetal globin expression in New World monkeys. J Biol Chem 1996. [DOI: 10.1016/s0021-9258(19)79281-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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94
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Emmett CJ, Stewart GR, Johnson RM, Aswani SP, Chan RL, Jakeman LB. Distribution of radioiodinated recombinant human nerve growth factor in primate brain following intracerebroventricular infusion. Exp Neurol 1996; 140:151-60. [PMID: 8690058 DOI: 10.1006/exnr.1996.0125] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The distribution of radioiodinated recombinant human nerve growth factor ([125I]rhNGF) was evaluated in adult cynomolgus monkeys following unilateral intracerebroventricular (icv) administration. Animals were cannulated into the right ventricle and recovered for 7 days. Monkeys were infused with 1.2 micrograms of [125I]rhNGF or [125I]rhNGF with a 140-fold excess of rhNGF. Twenty-four hours after infusion, animals were anesthetized and transcardially perfused with an aldehyde fixative. Coronal brain sections were processed for quantitative film autoradiography or for choline-acetyltransferase immunohistochemistry and then emulsion dipped. Specific radiolabel was distributed bilaterally and, with equal density, throughout the basal forebrain and was colocalized with choline acetyltransferase-positive neurons. Specific labeling was also present in the superficial ventral cortex. Nonspecific binding was observed surrounding the ventricles and lining blood vessels. These results demonstrate that unilateral icv infusion is an effective approach for delivering NGF to basal forebrain cholinergic neurons in primates and represents a viable drug delivery strategy for the therapeutic use of NGF in Alzheimer's Disease.
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Johnson RM, Buck S, Chiu C, Schneider H, Sampaio I, Gage DA, Shen TL, Schneider MP, Muniz JA, Gumucio DL, Goodman M. Fetal globin expression in New World monkeys. J Biol Chem 1996; 271:14684-91. [PMID: 8663037 DOI: 10.1074/jbc.271.25.14684] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Reverse phase chromatography of the globin chains of adult, newborn, and fetal erythrocytes from three species of New World monkeys (Cebus apella, Aotus azarae, and Callithrix jacchus) representing three of the seven platyrrhine clades showed that gamma-globin expression was fetal in these animals. The globins were identified by a combination of chemical sequencing and mass spectrometric analysis. Since gamma-globin expression is fetal in the other major simian branch, the catarrhines, but embryonic in prosimian primates and nonprimate placental mammals, the evolution of fetal recruitment can now be assigned to the period between the simian-prosimian divergence (55 million years ago) and the platyrrhine-catarrhine divergence (35 million years ago). The gamma-globin gene underwent tandem duplication during the same evolutionary epoch, in accord with a model that suggests that the downstream duplicated gamma-gene (gamma2) was free to acquire the mutations necessary for fetal recruitment. Mass spectrometric analysis of tryptic digests of the gamma-globins verified the amino acid sequences deduced from genomic sequencing. Detailed analysis of high performance liquid chromatography and matrix-assisted laser desorption/ionization mass spectrometry data showed that gamma2-globin in Cebus was expressed to a far greater extent than gamma1-globin, supporting inferences drawn from a study of the promoter sequences. A "pre-gamma"-globin was observed in C. apella and shown to be primarily the glutathionyl adduct. The other species, A. azarae and C. jacchus, also express only one gamma-globin polypeptide. This work provides biochemical evidence of an evolutionary trend in the platyrrhines to alter the duplicated gamma-globin gene locus so that only one gamma-globin polypeptide is expressed.
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Abstract
PURPOSE The use of red blood cell deformability measurements in the diagnosis of hemolytic anemia is reviewed. PATIENTS AND METHODS Results from 500 individuals are discussed. Erythrocytes were characterized by the automated measurement of cell deformability as the tonicity of the medium is varied (osmotic scan ektacytometry). RESULTS The measurement yields a reliable identification of hemolytic anemias caused by deficiencies or abnormalities in erythrocyte structural proteins. In addition, it can, with good reliability, signal the presence of a glycolytic enzyme deficiency. The scan is complete in 15 min, and can therefore give a rapid indication of the type of hemolytic anemia. The osmotic scans of other hemolytic anemias are also discussed. CONCLUSION The analysis of red blood cell deformability can offer a valuable addition to diagnostic methods in hemolytic anemia.
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Malczewski MC, Zamboni WA, Haws MJ, Johnson RM, Smoot EC, Russell RC. Effect of motion on digital nerve repair in a fresh cadaver model. Plast Reconstr Surg 1995; 96:1672-5. [PMID: 7480288 DOI: 10.1097/00006534-199512000-00022] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Information in the literature regarding the postoperative management of digital nerve lacerations is vague, and postoperative immobilization for up to 3 weeks is frequently recommended. In order to define more precisely what, if any, postoperative restrictions are necessary, a fresh cadaver model was designed for digital nerve division, resection, repair, and passive motion. Ten digital nerves were divided at the proximal interphalangeal joint and then repaired, mobilized, and inspected. Intact nerve repairs were serially resected in order to determine the limits of resection that would allow motion without repair disruption. All repairs were resistant to disruption even with hyperextension up to a resection length of 2.5 mm, and all repairs were resistant to disruption if splinted in neutral up to a resection length of 5 mm. There was not 100 percent disruption of repairs until a resection length of 1 cm and range of motion including hyperextension. These results give valuable objective data that can be used to guide early motion and splinting protocols after various degrees of digital nerve injury and repair.
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98
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Traweek ST, Liu J, Braziel RM, Johnson RM, Byrnes RK. Detection of myeloperoxidase gene expression in minimally differentiated acute myelogenous leukemia (AML-M0) using in situ hybridization. DIAGNOSTIC MOLECULAR PATHOLOGY : THE AMERICAN JOURNAL OF SURGICAL PATHOLOGY, PART B 1995; 4:212-9. [PMID: 7493141 DOI: 10.1097/00019606-199509000-00009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Acute leukemias containing > 3% myeloperoxidase (MPO)-positive blast cells, as detected cytochemically, are considered to be myelogenous in origin, regardless of the immunophenotypic markers expressed. Conversely, acute leukemias that express only myeloid antigens are also considered to be acute myelogenous leukemia (AML), even in the absence of MPO. These MPO-negative AMLs, designated AML-M0 in the FAB classification, currently require either immunophenotypic or electron microscopic studies for identification. To examine the association of MPO and myeloid antigen expression in AML, particularly at the early stages of myeloid cell differentiation, we have used in situ hybridization (ISH) to evaluate MPO gene expression in myeloid leukemia cell lines and a variety of well-characterized acute leukemias, including six cases of AML-M0. Strong positivity for MPO mRNA was detected in the myeloid leukemia cell line HL-60 and in 22 of 27 AMLs (three AML-M0, four AML-M1, eight AML-M2, five AML-M4, two AML-M5a). No MPO gene expression was detected in three AML-M0, one AML-M5a, one AML-M7, 5 acute lymphoblastic leukemia, the lymphoid cell lines Molt-4 and Namalwa, or in the early myeloid cell lines KG-1 and KG-1a. Ultrastructural studies for MPO activity were performed on four AML-M0; one leukemia showed both gene expression and cytochemical activity, whereas two others contained neither MPO transcripts nor enzyme. Weak MPO gene expression was evident in one AML-M0 that was negative for enzymatic activity by electron microscopy. These studies show MPO gene expression can be detected by ISH in about half of AML-M0, supporting their presumed myelocytic derivation.(ABSTRACT TRUNCATED AT 250 WORDS)
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MESH Headings
- Biomarkers, Tumor/analysis
- Burkitt Lymphoma/enzymology
- Burkitt Lymphoma/genetics
- Burkitt Lymphoma/pathology
- Cell Differentiation/genetics
- Gene Expression
- Humans
- In Situ Hybridization
- Leukemia, Lymphoid/enzymology
- Leukemia, Lymphoid/genetics
- Leukemia, Lymphoid/pathology
- Leukemia, Myeloid, Acute/enzymology
- Leukemia, Myeloid, Acute/genetics
- Leukemia, Myeloid, Acute/pathology
- Peroxidase/analysis
- Peroxidase/genetics
- Transcription, Genetic
- Tumor Cells, Cultured
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99
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Dean HJ, Warner MS, Terhune SS, Johnson RM, Spear PG. Viral determinants of the variable sensitivity of herpes simplex virus strains to gD-mediated interference. J Virol 1995; 69:5171-6. [PMID: 7609090 PMCID: PMC189341 DOI: 10.1128/jvi.69.8.5171-5176.1995] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Cells that express glycoprotein D (gD) of herpes simplex virus type 1 (HSV-1) resist infection by HSV-1 and HSV-2 because of interference with viral penetration. The results presented here show that both HSV-1 and HSV-2 gD can mediate interference and that various HSV-1 and HSV-2 strains differ in sensitivity to this interference. The relative degree of sensitivity was not necessarily dependent on whether the cell expressed the heterologous or homologous form of gD but rather on the properties of the virus. Marker transfer experiments revealed that the allele of gD expressed by the virus was a major determinant of sensitivity to interference. Amino acid substitutions in the most distal part of the gD ectodomain had a major effect, but substitutions solely in the cytoplasmic domain also influenced sensitivity to interference. In addition, evidence was obtained that another viral gene(s) in addition to the one encoding gD can influence sensitivity to interference. The results indicate that HSV-1 and HSV-2 gD share determinants required to mediate interference with infection by HSV of either serotype and that the pathway of HSV entry that is blocked by expression of cell-associated gD can be cleared or bypassed through subtle alterations in virion-associated proteins, particularly gD.
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100
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Johnson RM, McCarthy MC, Miller SF, Peoples JB. Craniofacial trauma in injured motorcyclists: the impact of helmet usage. THE JOURNAL OF TRAUMA 1995; 38:876-8. [PMID: 7602627 DOI: 10.1097/00005373-199506000-00008] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Helmets are effective in decreasing maxillofacial trauma in motorcycle crashes. The impact, however, of motorcycle crashes on the location and patterns of craniofacial injuries among helmeted versus unhelmeted patients has not been examined. In the present study, 331 injured motorcyclists were evaluated to compare the incidence of craniofacial and spinal injury in 77 (23%) helmeted and 254 (77%) nonhelmeted patients. Nonhelmeted motorcyclists were three times more likely to suffer facial fractures (5.2% vs. 16.1%) than those wearing helmets (p < 0.01). Skull fracture occurred in only one helmeted patient (1.2%), compared with 36 (12.3%) of nonhelmeted patients (p < or = 0.01). The incidence of spinal injury was not significantly different between the two groups. Blood alcohol levels demonstrated that 12% of the helmeted group were legally intoxicated (blood alcohol level > 100 mg/dL), in contrast to 37.9% of the nonhelmeted motorcyclists (p < or = 0.01). Failure to wear a helmet resulted in a significantly higher incidence of craniofacial injury among patients involved in motorcycle crashes, but did not affect spinal injury or mortality. Alcohol usage seemed to correlate with failure to use helmets. Helmet use should be legally mandated on a national level for all motorcyclists.
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