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Johnson K. Reauthorization of the Endangered Species Act. J Am Vet Med Assoc 1998; 212:488-9. [PMID: 9491152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Abstract
BACKGROUND This report details our experience in 13 patients with a technical modification of the standard central shunt. METHODS The study was performed using a retrospective chart review approach. In our operation, the aorto-Gore-Tex (W.L. Gore & Assoc, Flagstaff, AZ) anastomosis is created in a side-to-side fashion with the free end of the Gore-Tex shunt being oversewn. RESULTS All patients had echocardiographic evidence of shunt patency in the immediate postoperative period, and there have been no cases of late shunt occlusion at a mean follow-up period of 10 months. CONCLUSIONS We believe this approach will yield patency rates equivalent to or better than those of the standard central shunt. The technique has the advantage of creating a short, straight-lying shunt that is less likely to kink or be injured on repeated sternotomy and in which flow may be more reliable.
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Fontes ML, Mathew J, Johnson K, Rafferty T. Bicuspid noncalcific aortic stenosis: diagnostic limitations of intraoperative transesophageal echocardiography. J Cardiothorac Vasc Anesth 1998; 12:58-60. [PMID: 9509358 DOI: 10.1016/s1053-0770(98)90056-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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429
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Jones MZ, Alroy J, Boyer PJ, Cavanagh KT, Johnson K, Gage D, Vorro J, Render JA, Common RS, Leedle RA, Lowrie C, Sharp P, Liour SS, Levene B, Hoard H, Lucas R, Hopwood JJ. Caprine mucopolysaccharidosis-IIID: clinical, biochemical, morphological and immunohistochemical characteristics. J Neuropathol Exp Neurol 1998; 57:148-57. [PMID: 9600207 DOI: 10.1097/00005072-199802000-00006] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Several animal models have been developed for the mucopolysaccharidoses (MPSs), a group of lysosomal storage disorders caused by lysosomal hydrolase deficiencies that disrupt the catabolism of glycosaminoglycans (GAG). Among the MPS, the MPS-III (Sanfilippo) syndromes lacked an animal counterpart until recently. In this investigation of caprine MPS-IIID, the clinical, biochemical, morphological, and immunohistochemical studies revealed severe and mild phenotypes like those observed in human MPS III syndromes. Both forms of caprine MPS IIID result from a nonsense mutation and consequent deficiency of lysosomal N-acetylglucosamine 6-sulfatase (G6S) activity and are associated with tissue storage and urinary excretion of heparan sulfate (HS). Using special stains, immunohistochemistry, and electron microscopy, secondary lysosomes filled with GAG were identified in most tissues from affected goats. Primary neuronal accumulation of HS and the secondary storage of gangliosides were observed in the central nervous system (CNS) of these animals. In addition, morphological changes in the CNS such as neuritic expansions and other neuronal alterations that may have functional significance were also seen. The spectrum of lesions was greater in the severe form of caprine MPS IIID and included mild cartilaginous, bony, and corneal lesions. The more pronounced neurological deficits in the severe form were partly related to a greater extent of CNS dysmyelination. These findings demonstrate that caprine MPS IIID is a suitable animal model for the investigation of therapeutic strategies for MPS III syndromes.
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430
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Petrini J, Damus K, Roy S, Johnson K, Johnston RB. The effect of using "race of child" instead of "race of mother" on the black-white gap in infant mortality due to birth defects. Public Health Rep 1998; 113:263-7. [PMID: 9633874 PMCID: PMC1308680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE For at least 20 years, birth defects have been the leading cause of infant mortality in the United States. Some studies have reported higher rates for black infants than white infants of mortality due to birth defects, while other studies have reported no black-white differences. The authors analyzed the effect on these rates of a change in the way the National Center for Health Statistics (NCHS) tabulates "race" for newborns. METHODS The authors calculated infant mortality rates due to birth defects for 1980-1993 using two standard methods of assigning newborns to "racial" categories: a "race of child" algorithm and the "race of mother" approach currently used by NCHS. RESULTS From 1980 through 1993, birth defect-specific infant mortality rates (BD-IMRs) were significantly higher for black infants than white infants 12 of the 14 years by "race of mother" and only 5 of 14 years by "race of child." Calculation of BD-IMRs by "race of mother" reduced the rate for white infants and increased the rate for black infants in each of the 14 years. The choice of method for assigning newborns to "racial" categories had a progressively greater effect over time on the black-white gap in BD-IMRs. CONCLUSIONS Calculations of trends in "race"-specific BD-IMRs by may vary substantially by whether "race of mother" or "race of child" is used. Identifying the method of tabulation is imperative for appropriate comparisons and interpretations.
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431
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Lehmann CU, Wang DJ, Kim GR, Johnson K. Utilization of a paediatric link collection by health professionals and laypersons. MEDICAL INFORMATICS = MEDECINE ET INFORMATIQUE 1998; 23:53-62. [PMID: 9618683 DOI: 10.3109/14639239809001391] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The Internet is an evolving resource for health-care information. However little information exists on providers' and other web patrons' usage of the 'medical' Internet. This study aims to characterize the users of a large paediatric link collection, describe their objectives and track their use of the information provided by the site. We utilized a paediatric link collection called the Pediatric Points of Interest (POI) and a combination of a questionnaire, unique user identifier and link-tracking system to collect data about POI patrons' demographics and Internet resource utilization. During a five week period, 5216 individuals visited the POI and requested 36,187 links. The majority of users had less than one year of Internet experience and were first-time visitors to the POI. More than 83% of users were from North America. Medical professionals were more likely to return to the POI during the study period and reported visiting the POI mainly for 'medical education', 'research', 'resource identification', and 'disease specific information'; they proceeded primarily to the resource categories 'Medical Institutions and Agencies' (32%) and 'Professional Education and Resources' (28%). Laypersons expressed the greatest interest in 'disease specific information' and 'patient education' and most frequently visited the category. 'Patient Education' (42%). On average, users were able to identify resources related to their stated goals within one level of searching. Health care providers and other web patrons are actively utilizing Internet sites to seek medical information and are able to identify resources with a minimum of searching.
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432
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Rosenbaum S, Johnson K, Sonosky C, Markus A, DeGraw C. The children's hour: the State Children's Health Insurance Program. Health Aff (Millwood) 1998; 17:75-89. [PMID: 9455017 DOI: 10.1377/hlthaff.17.1.75] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The State Children's Health Insurance Program (CHIP) is the product of a series of policy and political compromises and generates numerous structural and policy issues for states. CHIP entitles states to federal financial aid to provide health assistance to targeted children, through Medicaid expansions, new program implementation, or a product of the two. States that elect to operate CHIP programs apart from Medicaid have enormous discretion under the law to determine how they will structure their programs, the services they will cover, the form that benefits will take, and the conditions of participation and consumer protections that will apply. Determining what approach to take, as well as how to respond to the choices posed by the statute, represents a major test of how states address the needs of children and families.
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433
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Fleming MF, Manwell LB, Barry KL, Johnson K. At-risk drinking in an HMO primary care sample: prevalence and health policy implications. Am J Public Health 1998; 88:90-3. [PMID: 9584040 PMCID: PMC1508398 DOI: 10.2105/ajph.88.1.90] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVES This study was designed to determine the prevalence of at-risk drinking using varying alcohol use criteria. METHODS A period prevalence survey was conducted in 22 primary care practices (n = 19372 adults). RESULTS The frequency of at-risk alcohol use varied from 7.5% (World Health Organization criteria) to 19.7% (National Institute on Alcohol Abuse and Alcoholism criteria). A stepwise logistic model using National Institute on Alcohol Abuse and Alcoholism criteria found male gender, current tobacco use, never married status, retirement, and unemployment to be significant predictors of at-risk alcohol use. CONCLUSIONS Public health policy needs to move to a primary care paradigm focusing on identification and treatment of at-risk drinkers.
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Childs J, Shope RE, Fish D, Meslin FX, Peters CJ, Johnson K, Debess E, Dennis D, Jenkins S. Emerging zoonoses. Emerg Infect Dis 1998; 4:453-4. [PMID: 9716969 PMCID: PMC2640307 DOI: 10.3201/eid0403.980328] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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435
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Taylor VM, Thompson B, Montano DE, Mahloch J, Johnson K, Li S. Mammography use among women attending an inner-city clinic. JOURNAL OF CANCER EDUCATION : THE OFFICIAL JOURNAL OF THE AMERICAN ASSOCIATION FOR CANCER EDUCATION 1998; 13:96-101. [PMID: 9659628 DOI: 10.1080/08858199809528524] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
BACKGROUND Low-income, minority, and inner city women have breast cancer screening rates that are below those of the general population. METHODS The authors surveyed women who received primary care at Seattle's county hospital about their mammography behaviors in early 1995. Data were analyzed within the context of the PRECEDE framework. RESULTS Only half (48%) of the women were obtaining regular screening. Breast cancer and mammography beliefs differed by racial group. The following factors differentiated between inner-city women who were and were not regular users: mammography beliefs concerning early detection of disease, pressure from the machine causing breast cancer, and cost (these were less important among white women than members of other racial groups); previous physician discussions, concerns about appointment scheduling, and transportation problems; and social support from physicians, family, and friends. CONCLUSION Interventions to encourage regular screening among inner-city women should address predisposing, enabling, and reinforcing factors.
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436
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Nader-Djalal N, Knight PR, Davidson BA, Johnson K. Hyperoxia exacerbates microvascular lung injury following acid aspiration. Chest 1997; 112:1607-14. [PMID: 9404761 DOI: 10.1378/chest.112.6.1607] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
OBJECTIVES To examine the effects of an increase in ambient oxygen (O2) concentrations on the extent of inflammatory pulmonary damage following acid aspiration. DESIGN Prospective, controlled laboratory study. SETTINGS University-affiliated animal research facility. SUBJECTS Male, Long Evans rats weighing 250 to 300 g. INTERVENTION Rats were injured by instillation of 1.2 mL/kg normal saline solution/HCl, pH= 1.25 (acid), into the lungs via a tracheotomy. Animals were allowed to awaken and were exposed to 21%, 50%, or 98% O2 for 0 to 5 h (n/group > or = 10). In a separate set of experiments, injured rats exposed to 98% O2 were treated with different doses of deferoxamine, just prior to injury. Uninjured rats and rats injured with normal saline solution, pH = 5.3, were used as the control group. MEASUREMENTS Injury was determined by assessing lung function (lung compliance and arterial blood gases) and alveolar-capillary wall integrity (wet/dry weight, lung albumin permeability index [PI], and intrapulmonary hemorrhage [HI]). RESULTS Intrapulmonary instillation of acid increased PI, HI, and decreased static lung compliance compared to uninjured control animals. Increased ambient oxygen following acid aspiration decreased lung compliance, 1.06+/-0.03 mL/kg/cm H2O, in oxygen-exposed lungs when compared to the lungs exposed to air, 1.26+/-0.04, following a low pH aspirate (p<0.05). An increase in protein leakage into the lung tissue was noted in oxygen-exposed animals, PI=1.33+/-0.10, vs air-exposed rats, 0.89+/-0.07 (p<0.05). The hyperoxia-induced increase in lung injury was prevented by 30 mg/kg or higher deferoxamine treatment, 0.78+/-0.05 (p<0.05). Exposure of animals to 98% O2 for 2 h was sufficient to produce the same increase in microvascular protein leakage as 5-h exposure to O2 following low pH aspirate. CONCLUSION Hyperoxia increases acid aspiration-induced inflammatory microvascular lung injury. This appears to be mediated by production of reactive species of O2.
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Hoffman E, Maraldo P, Coons HL, Johnson K. The women-centered health care team: integrating perspectives from managed care, women's health, and the health professional workforce. Womens Health Issues 1997; 7:362-74; discussion 375-9. [PMID: 9439197 DOI: 10.1016/s1049-3867(97)00074-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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438
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Wosikowski K, Schuurhuis D, Johnson K, Paull KD, Myers TG, Weinstein JN, Bates SE. Identification of epidermal growth factor receptor and c-erbB2 pathway inhibitors by correlation with gene expression patterns. J Natl Cancer Inst 1997; 89:1505-15. [PMID: 9337347 DOI: 10.1093/jnci/89.20.1505] [Citation(s) in RCA: 93] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Growth factor receptor-signaling pathways are potentially important targets for anticancer therapy. The interaction of anticancer agents with specific molecular targets can be identified by correlating target expression patterns with cytotoxicity patterns. We sought to identify new agents that target and inhibit the activity of the epidermal growth factor (EGF) receptor and of c-erbB2 (also called HER2 or neu), by correlating EGF receptor, transforming growth factor (TGF)-alpha (a ligand for EGF receptor), and c-erbB2 messenger RNA (mRNA) expression levels with the results of cytotoxicity assays of the 49000 compounds in the National Cancer Institute (NCI) drug screen database. METHODS The levels of mRNAs were measured and used to generate a molecular target database for the 60 cell lines of the NCI anticancer drug screen. The computer analysis program, COMPARE, was used to search for cytotoxicity patterns in the NCI drug screen database that were highly correlated with EGF receptor, TGF-alpha, or c-erbB2 mRNA expression patterns. The putative EGF receptor-inhibiting compounds were tested for effects on basal tyrosine phosphorylation, in vitro EGF receptor tyrosine kinase activity, and EGF-dependent growth. Putative ErbB2-inhibiting compounds were tested for effects on antibody-induced ErbB2 tyrosine kinase activity. RESULTS EGF receptor mRNA and TGF-alpha mRNA levels were highest in cell lines derived from renal cancers, and c-erbB2 mRNA levels were highest in cells derived from breast, ovarian, and colon cancers. Twenty-five compounds with high correlation coefficients (for cytotoxicity and levels of the measured mRNAs) were tested as inhibitors of the EGF receptor or c-erbB2 signaling pathways; 14 compounds were identified as inhibitors of these pathways. The most potent compound, B4, inhibited autophosphorylation (which occurs following activation) of ErbB2 by 50% in whole cells at 7.7 microM. CONCLUSIONS Novel EGF receptor or c-erbB2 pathway inhibitors can be identified in the NCI drug screen by correlation of cytotoxicity patterns with EGF receptor or c-erbB2 mRNA expression levels.
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Woeltje KF, Kilo CM, Johnson K, Primack J, Fraser VJ. Tuberculin skin testing of hospitalized patients. Infect Control Hosp Epidemiol 1997. [PMID: 9276237 DOI: 10.2307/30141266] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
OBJECTIVES We sought to define the prevalence of tuberculin skin test (TST) positivity in a group of newly hospitalized patients, to identify risk factors for positive tests, and to examine the impact of testing on infection control practices. DESIGN Unblinded cohort study over 5 days in July 1992. SETTING A 1,000-bed university-affiliated hospital. PATIENTS All patients admitted (excluding obstetric patients and newborns) were interviewed. Patients without a history of tuberculosis (TB) or a positive TST were offered a TST with Candida and tetanus controls. RESULTS Of 346 patients offered the test, 21 (6%) had a prior history of TB or a positive TST, and 36 (10%) declined to participate; 279 of the remaining 289 completed the study. Anergy was demonstrated in 94 (33.7%) of 279 patients. New positive TSTs were identified in 19 (10.3%) of 185 nonanergic patients. Of the 19 TST-positive patients, 6 (32%) had infiltrates on chest radiographs and were evaluated for active TB. One patient was treated empirically for active TB, and five received isoniazid prophylaxis. Risk factors for a new positive TST included age (odds ratio [OR], 1.56 per decade of life; P = .021), African American race (OR, 4.81; P = .008), alcohol abuse (OR, 5.53; P = .005), and peptic ulcer disease (OR, 4.53; P = .017). Risk factors for anergy included admission to a surgical service (OR, 2.1; P = .006), current use of steroids (OR, 2.65; P = .005), and human immunodeficiency virus (HIV) infection (OR, undefined; P = .034). CONCLUSIONS Despite a high rate of anergy, routine tuberculin skin testing identified a substantial number of patients with TB infection who might otherwise have gone unrecognized.
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440
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Ferraro FR, Wonderlich S, Johnson K. Do individuals at risk for eating disorders exhibit negative priming deficits? THE JOURNAL OF GENERAL PSYCHOLOGY 1997; 124:381-90. [PMID: 9499585 DOI: 10.1080/00221309709595567] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Fifty people (25 at risk for an eating disorder, 25 controls) performed a simple reaction-time (SRT) task and a negative-priming (NP) task. The two groups did not differ on the SRT task. For the NP task, the controls displayed the NP effect (responses on critical trials were slower than responses on control trials). At-risk participants, however, revealed no such NP effect. Although the pattern of NP performance in the at-risk participants may indicate that they as a group had deficiencies in their ability to inhibit irrelevant information, it is also possible that issues related to obsessionality, perfectionism, and restraint in the at-risk group affected the results.
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441
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Brillhart B, Johnson K. Motivation and the coping process of adults with disabilities: a qualitative study. Rehabil Nurs 1997; 22:249-52, 255-6. [PMID: 9341546 DOI: 10.1002/j.2048-7940.1997.tb02111.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Adults with disabilities who have completed rehabilitation programs and have returned to active lifestyles are experts on the importance of motivation after an injury or an illness. This qualitative descriptive study was conducted with 9 men and 3 women who had completed a spinal cord injury rehabilitation program at a rehabilitation hospital. The subjects were asked two questions: What helped motivate you during rehabilitation to return to an active, productive life? and How did rehabilitation nurses and staff assist you with that process? An analysis of the interviews revealed five motivational categories--independence, education, socialization, self-esteem, and realization--within the specific themes of nursing and healthcare interventions. Gaining insight into the motivation of adults who have coped with disabilities effectively can help rehabilitation nurses determine how they can promote the motivation that clients need to achieve a quality lifestyle.
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442
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Nelson M, Nicolete J, Johnson K. Integration or evolution: women's health as a model for interdisciplinary change in medical education. ACADEMIC MEDICINE : JOURNAL OF THE ASSOCIATION OF AMERICAN MEDICAL COLLEGES 1997; 72:737-740. [PMID: 9311312 DOI: 10.1097/00001888-199709000-00005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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443
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Woeltje KF, Kilo CM, Johnson K, Primack J, Fraser VJ. Tuberculin skin testing of hospitalized patients. Infect Control Hosp Epidemiol 1997; 18:561-5. [PMID: 9276237 DOI: 10.1086/647672] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVES We sought to define the prevalence of tuberculin skin test (TST) positivity in a group of newly hospitalized patients, to identify risk factors for positive tests, and to examine the impact of testing on infection control practices. DESIGN Unblinded cohort study over 5 days in July 1992. SETTING A 1,000-bed university-affiliated hospital. PATIENTS All patients admitted (excluding obstetric patients and newborns) were interviewed. Patients without a history of tuberculosis (TB) or a positive TST were offered a TST with Candida and tetanus controls. RESULTS Of 346 patients offered the test, 21 (6%) had a prior history of TB or a positive TST, and 36 (10%) declined to participate; 279 of the remaining 289 completed the study. Anergy was demonstrated in 94 (33.7%) of 279 patients. New positive TSTs were identified in 19 (10.3%) of 185 nonanergic patients. Of the 19 TST-positive patients, 6 (32%) had infiltrates on chest radiographs and were evaluated for active TB. One patient was treated empirically for active TB, and five received isoniazid prophylaxis. Risk factors for a new positive TST included age (odds ratio [OR], 1.56 per decade of life; P = .021), African American race (OR, 4.81; P = .008), alcohol abuse (OR, 5.53; P = .005), and peptic ulcer disease (OR, 4.53; P = .017). Risk factors for anergy included admission to a surgical service (OR, 2.1; P = .006), current use of steroids (OR, 2.65; P = .005), and human immunodeficiency virus (HIV) infection (OR, undefined; P = .034). CONCLUSIONS Despite a high rate of anergy, routine tuberculin skin testing identified a substantial number of patients with TB infection who might otherwise have gone unrecognized.
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Yung R, Chang S, Hemati N, Johnson K, Richardson B. Mechanisms of drug-induced lupus. IV. Comparison of procainamide and hydralazine with analogs in vitro and in vivo. ARTHRITIS AND RHEUMATISM 1997; 40:1436-43. [PMID: 9259423 DOI: 10.1002/art.1780400811] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE T cells treated with DNA methylation inhibitors overexpress lymphocyte function-associated antigen 1 (LFA-1), which results in autoreactivity, and the autoreactive cells cause a lupus-like disease in vivo, suggesting a mechanism by which some agents may cause drug-induced lupus. This study compared the effects of procainamide (Pca) and hydralazine (Hyd) with those of structural analogs, to determine if the degree of LFA-1 overexpression and T cell autoreactivity correlated with the ability of the agents to induce autoimmunity. METHODS Cloned murine T helper 2 cells were treated with Pca, N-acetylprocainamide, Hyd, Phthalazine, or hydroxyurea (HU). The treated cells were then compared for LFA-1 overexpression, autoreactivity, and the ability to induce autoimmunity in vivo. RESULTS Pca and Hyd were more potent than their analogs or HU in all 3 assays. CONCLUSION The results support a relationship between LFA-1 overexpression, T cell autoreactivity, and autoimmunity, and suggest a mechanism by which Pca and Hyd, but not the analogs, may cause drug-induced lupus.
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Cook S, Johnson K, Davisson M. The mouse urate oxidase gene, Uox, maps to distal chromosome 3. Mamm Genome 1997; 8:623-4. [PMID: 9250879 DOI: 10.1007/s003359900522] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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446
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Kim J, Johnson K, Chen HJ, Carroll S, Laughon A. Drosophila Mad binds to DNA and directly mediates activation of vestigial by Decapentaplegic. Nature 1997; 388:304-8. [PMID: 9230443 DOI: 10.1038/40906] [Citation(s) in RCA: 419] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The TGF-beta (transforming growth factor-beta)-related signalling proteins, including Decapentaplegic (Dpp) in Drosophila-and bone morphogenic proteins and activin in vertebrates, affect the growth and patterning of a great variety of structures. However, the mechanisms by which these ligands regulate gene expression are not understood. Activation of complexes of type I with type II receptors results in the phosphorylation and nuclear localization of members of the SMAD protein family, which are thought to act as co-activators of transcription, perhaps in conjunction with sequence-specific cofactors. Here we show that the amino-terminal domain of the Drosophila Mothers against dpp protein (Mad), a mediator of Dpp signalling, possesses a sequence-specific DNA-binding activity that becomes apparent when carboxy-terminal residues are removed. Mad binds to and is required for the activation of an enhancer within the vestigial wing-patterning gene in cells across the entire developing wing blade. Mad also binds to Dpp-response elements in other genes. These results suggest that Dpp signalling regulates gene expression by activating Mad binding to target gene enhancers.
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Sundberg JP, Boggess D, Hogan ME, Sundberg BA, Rourk MH, Harris B, Johnson K, Dunstan RW, Davisson MT. Harlequin ichthyosis (ichq): a juvenile lethal mouse mutation with ichthyosiform dermatitis. THE AMERICAN JOURNAL OF PATHOLOGY 1997; 151:293-310. [PMID: 9212754 PMCID: PMC1857926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The harlequin ichthyosis (ichq) mouse mutation arose spontaneously in 1989 in a colony of BALB/cJ mice at The Jackson Laboratory. Affected mice developed thick skin due to formation of compact, orthokeratotic scales that fractured over articular surfaces, secondary to bending. Harlequin ichthyosis mice on the inbred BALB/cJ background died between 9 and 12 days of age. Onset of the clinical phenotype corresponded with emergence of hair fibers from follicles at 5 days of age. There was marked proliferation of the root sheaths of anagen hair follicles, limited to the region within the dermis. Sebaceous glands were present but small compared with those of littermate controls. Emerging hair fibers were surrounded by a thick, compact sheath of cornified cells. Mutant skin contained large mitochondria with lamellar-shaped, electron-dense structures at the ultrastructural level. Keratohyalin granules were smaller and less pleomorphic than those in control mice. Lamellar bodies were not evident in either mutant or littermate control mice. Using a panel of antibodies to evaluate changes in keratinocyte differentiation, mouse-specific keratin 6 was overexpressed in the suprabasilar, hyperplastic epidermis. Loricrin expression, within the cytoplasm of cells in the stratum granulosum, decreased rapidly postmortem, unlike that in normal mice where it was stable for over 24 hours postmortem. Filaggrin expression, within granules of cells in the stratum granulosum, was prominent, corresponding to hypergranulosis evident by light microscopy in mutant mouse skin. Skin grafts from harlequin ichthyosis mice grafted onto immunodeficient nude mice maintained the phenotype for the 10-week observation period. The mutant gene locus mapped to the proximal end of mouse chromosome 19 and is inherited as a fully penetrant autosomal recessive gene. The harlequin ichthyosis mouse mutation is very similar to human type 2 harlequin ichthyosis for which it may be a good model.
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MESH Headings
- Animals
- Animals, Newborn
- Chromosome Mapping
- Crosses, Genetic
- Dermatitis/genetics
- Dermatitis/pathology
- Disease Models, Animal
- Female
- Filaggrin Proteins
- Genes, Lethal
- Ichthyosis, Lamellar/genetics
- Ichthyosis, Lamellar/pathology
- Image Processing, Computer-Assisted
- Immunohistochemistry
- Male
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Mutant Strains
- Mice, Nude
- Mutation
- Phenotype
- Skin Transplantation
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Yung R, Williams R, Johnson K, Phillips C, Stoolman L, Chang S, Richardson B. Mechanisms of drug-induced lupus. III. Sex-specific differences in T cell homing may explain increased disease severity in female mice. ARTHRITIS AND RHEUMATISM 1997; 40:1334-43. [PMID: 9214435 DOI: 10.1002/1529-0131(199707)40:7<1334::aid-art19>3.0.co;2-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE To determine if sex-specific differences in lymphocyte trafficking could contribute to increased disease severity in female mice. METHODS A lupus-like disease was induced by injecting male and female mice with procainamide-treated T cell clones. Trafficking was examined by labeling the injected cells with 51Cr or 5-chloromethylfluorescein diacetate. RESULTS Females developed more autoimmune liver disease and greater titers of anti-DNA antibodies than did males, and 2-7 times more cells accumulated in the female spleens. Splenectomy prevented the development of autoantibodies and renal and liver disease. Oophorectomy decreased the splenic homing, autoantibody titer, and liver disease severity, to levels found in males. CONCLUSION T cells traffic differently to the spleen in male and female mice, and the spleen appears to be essential in the disease process. This suggests that differences in T cell homing could contribute to sex-specific disease severity in this murine model, and also possibly in human disease.
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449
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Johnson K. Blinding of clinical trials with concurrent economic analysis. JAMA 1997; 277:1677. [PMID: 9169884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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450
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Martorell L, Johnson K, Boucher CA, Baiget M. Somatic instability of the myotonic dystrophy (CTG)n repeat during human fetal development. Hum Mol Genet 1997; 6:877-80. [PMID: 9175733 DOI: 10.1093/hmg/6.6.877] [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] Open
Abstract
Myotonic dystrophy is characterised by the striking level of somatic heterogeneity seen between and within tissues of the same patient, which probably accounts for a significant proportion of the pleiotropy associated with this disorder. The congenital form of the disease is associated with the largest (CTG)n repeat expansions. We have investigated the timing of instability of myotonic dystrophy (CTG)n repeats in a series of congenitally affected fetuses and neonates. We find that during the first trimester the repeat is apparently stable and that instability only becomes detectable during the second and third trimesters. In our series repeat instability is apparent only after 13 weeks gestational age and before 16 weeks. The appearance of heterogeneity shows some tissue specificity, with heart most commonly having the largest expansion. The degree of heterogeneity is not correlated with initial expansion size as gauged by chorionic villus and blood (CTG)n repeat sizes.
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