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Newton MG, King RB, Chang M, Gimeno J. Complete substitution of carbonyl groups in cyclopentadienyliron dicarbonyl dimer by methylaminobis(difluorophosphine). A novel bridging CH3NPF2 ligand bonded to metals through both phosphorus and nitrogen. J Am Chem Soc 2002. [DOI: 10.1021/ja00473a066] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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152
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Newton MG, King RB, Chang M, Gimeno J. Tetrakis[methylaminobis(difluorophosphine)]carbonyldiiron: unsymmetrical bonding of methylaminobis(difluorophosphine) to a pair of transition metals involving phosphorus-nitrogen bond cleavage. J Am Chem Soc 2002. [DOI: 10.1021/ja00469a077] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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153
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Newton MG, King RB, Chang M, Gimeno J. Novel bimetallic products from iron carbonyls and methylaminobis(difluorophosphine): an example of square pyramidal pentacoordinate iron(0). J Am Chem Soc 2002. [DOI: 10.1021/ja00450a069] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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154
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King RB, Chang M. Metal complexes of fluorophosphines. 7. Cocondensations of some first-row transition-metal vapors with (dimethylamino)difluorophosphine and (methylamino)bis(difluorophosphine). Inorg Chem 2002. [DOI: 10.1021/ic50192a032] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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155
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Selco JI, Brooks T, Chang M, Trieu MT, McDonald JK, McManus SP. Solution photochemistry of azulene. J Org Chem 2002. [DOI: 10.1021/jo00081a024] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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156
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Chang M, Kim H, Shigematsu R, Nho H, Nishijima T, Tanaka K. Functional fitness may be related to life satisfaction in older Japanese adults. Int J Aging Hum Dev 2002; 53:35-49. [PMID: 11678355 DOI: 10.2190/3xjl-x2yt-2p2c-etef] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The relationship between functional fitness status and life satisfaction was assessed in older Japanese people from the perspective of quality of life (QOL). A total of 123 older men and women (M = 74.3 years, SD = 5.4) participated in the study. The questionnaire contained 21 questions covering eight structural factors pertaining to the feelings of life satisfaction in older people. The functional fitness test consisted of nine items representing the following five areas of fitness: muscular strength, agility, coordination, balance, and flexibility. The analysis revealed no overall correlation between the total fitness and the total life satisfaction scores, but some of the life satisfaction factors were significantly related to some functional fitness items (P < .01). The results suggest it is important for older people to maintain their functional fitness in order to manage a high quality of life.
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Chen Y, Chang M, Wang ZZ, Chen LX, Yang Q, Qi YM, Wang R. [Nphe1]nociceptin(1-13)-NH2 antagonizes nociceptin-induced hypotension, bradycardia, and hindquarters vasodilation in the anesthetized rat. Can J Physiol Pharmacol 2002; 80:31-5. [PMID: 11911223 DOI: 10.1139/y02-003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of this study was to investigate the effects of [Nphe1]nociceptin(1-13)-NH2 on nociceptin-induced decreases in mean arterial pressure (MAP), heart rate (HR), and hindquarters vascular bed resistance (HVBR) of the anesthetized rat. The results showed that i.c.v. or i.v. [Nphe1]nociceptin(1-13)-NH2 (1.5-12 nmol/kg and 5-120 nmol/kg, respectively) could antagonize the depressor effects of i.c.v. or i.v. nociceptin (3 and 30 nmol/kg, respectively) on MAP and HR. Furthermore, [Nphe1]nociceptin(1-13)-NH2 (5-120 nmol/kg) could reverse nociceptin (30 nmol/kg)-induced decrease of HVBR. However, [Nphe1]nociceptin(1-13)-NH2 had no significant effects on similar effects induced by morphine. Our results suggest that [Nphe1]nociceptin(1-13)-NH2 acts as a selective antagonist of the nociceptin receptor in the cardiovascular system of the rat.
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Abstract
The purpose of this article is to explore assaultive behavior of psychiatric in-patients in a hospital and to examine the interplay of patient, environmental, and staff factors related to assault. The present study was carried out prospectively using standardized instruments applied in four acute wards in one hospital. A log system was used to record the occurrence of assaults. The results showed 595 episodes of assault from 238 patients in 7 months. Forty one nurses participated in the study. To further examine the differences between assaultive and non-assaultive patients, and assaulted and non-assaulted nurses, a logistic regression analysis was used. The results indicated that patient factors (diagnosis, history of assault, time since admission, and history of smoking), environmental factors (patient/nurse ratio and spatial density), and staff factors (age, length of work experience, training program received in prevention and management of assaults) are contributing variables to assaultive behavior. The present study examined a wider range of variables than have been included in many previous studies. This reinforces the necessary complexity of models likely to prove useful in predicting assaults among psychiatric inpatients.
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Tsai CL, Yang YF, Han CC, Hsieh JH, Chang M. Measurement and simulation of light distribution in biological tissues. APPLIED OPTICS 2001; 40:5770-5777. [PMID: 18364868 DOI: 10.1364/ao.40.005770] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Lateral light-distribution images of biologic tissues were used to study the tissues' optical characteristics. Monte Carlo simulation with the same conditions was performed to simulate the light distribution for comparison. Simulation results showed that the lateral light distribution was similar to the internal light distribution in biologic tissue. The direction of muscle fibers and the temperature both affect the near-field light distribution in tissue. The lateral view distribution can be both measured and simulated to study photon migration in tissue. It can also be used to estimate or verify the optical coefficients of tissue.
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Shigematsu R, Tanaka K, Holland G, Nakagaichi M, Chang M, Takeshima N, Noda F, Tanaka Y, Mimura K. Validation of the functional fitness age (FFA) index in older Japanese women. Aging Clin Exp Res 2001; 13:385-90. [PMID: 11820712 DOI: 10.1007/bf03351507] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Functional fitness age (FFA), which we previously described, is a measure of functional age that reflects a person's overall physical ability to complete daily tasks such as preparing meals and performing various household chores. The purpose of this study was to validate FFA in two elderly populations: 1) older subjects from different communities, and 2) older subjects participating in an exercise intervention program. FFA was calculated from 4 performance tests: performing arm curls; moving beans with chopsticks; demonstrating functional reach; and sitting and walking around two cones. The first study group was selected from 4 different communities (N=127), and was subdivided into a less active group (N=87) and an active group (N=40). The results of the 4 tests for the less active group were not significantly different from those for the original validation group used in developing the FFA equation. The FFA of the less active group (71.1+/-7.7 yrs) was not different from their chronological age (70.4+/-6.6 yrs). In the active group, except for the arm curls, test scores were significantly higher than those of the original validation group. The FFA of the active group (66.2+/-5.1 yrs) was significantly younger than their chronological age (70.9+/-4.2 yrs). Another group of 14 older women (79.5+/-3.9 yrs) was recruited for pre- and post-training testing. After the 3-month exercise program, they showed significant improvements in sitting and walking around two cones and functional reach; their FFA decreased significantly from 81.5+/-5.0 yrs to 78.3+/-4.5 yrs. The control group selected from the same community (N=16, 79.8+/-5.3 yrs) showed no significant changes in the 4 performance tests, and their FFA remained unchanged. These results indicate that our FFA is highly cross-validated for different Japanese communities, and is sensitive to changes associated with participation in an exercise intervention program.
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Baetz K, Moffat J, Haynes J, Chang M, Andrews B. Transcriptional coregulation by the cell integrity mitogen-activated protein kinase Slt2 and the cell cycle regulator Swi4. Mol Cell Biol 2001; 21:6515-28. [PMID: 11533240 PMCID: PMC99798 DOI: 10.1128/mcb.21.19.6515-6528.2001] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In Saccharomyces cerevisiae, the heterodimeric transcription factor SBF (for SCB binding factor) is composed of Swi4 and Swi6 and activates gene expression at the G(1)/S-phase transition of the mitotic cell cycle. Cell cycle commitment is associated not only with major alterations in gene expression but also with highly polarized cell growth; the mitogen-activated protein kinase (MAPK) Slt2 is required to maintain cell wall integrity during periods of polarized growth and cell wall stress. We describe experiments aimed at defining the regulatory pathway involving the cell cycle transcription factor SBF and Slt2-MAPK. Gene expression assays and chromatin immunoprecipitation experiments revealed Slt2-dependent recruitment of SBF to the promoters of the G(1) cyclins PCL1 and PCL2 after activation of the Slt2-MAPK pathway. We performed DNA microarray analysis and identified other genes whose expression was reduced in both SLT2 and SWI4 deletion strains. Genes that are sensitive to both Slt2 and Swi4 appear to be uniquely regulated and reveal a role for Swi4, the DNA-binding component of SBF, which is independent of the regulatory subunit Swi6. Some of the Swi4- and Slt2-dependent genes do not require Swi6 for either their expression or for Swi4 localization to their promoters. Consistent with these results, we found a direct interaction between Swi4 and Slt2. Our results establish a new Slt2-dependent mode of Swi4 regulation and suggest roles for Swi4 beyond its prominent role in controlling cell cycle transcription.
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Abstract
OBJECTIVE To evaluate the efficacy of 0.5% proparacaine stored at room temperature for 6 weeks. ANIMALS STUDIED Six normal dogs, evaluated on a weekly basis for 6 weeks. PROCEDURE Proparacaine stored at 4 degrees C or at room temperature, was evaluated in the right and left eye of each dog, respectively. Corneal sensitivity was assessed with a Cochet-Bonnet aesthesiometer before and after instillation of proparacaine at each time point. RESULTS A statistically significant difference was seen in corneal sensitivity beginning at week 3 for the eyes receiving room-temperature proparacaine compared to refrigerated proparacaine. Differences were not seen between right and left eyes before instillation of proparacaine for any time point, nor for eyes receiving refrigerated proparacaine over the 6 week study period. CONCLUSION Short-term storage of proparacaine at room temperature did not affect efficacy, but storage at room temperature for more than 2 weeks resulted in a decrease in drug effect.
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Lee S, Sharm Y, Lee TK, Chang M, Davis KR. Lignification induced by pseudomonads harboring avirulent genes on Arabidopsis. Mol Cells 2001; 12:25-31. [PMID: 11561727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023] Open
Abstract
The responses of Arabidopsis thaliana ecotypes to the bacterial pathogen Pseudomonas syringae pv. maculicola 4326 (Psm4326) harboring cloned avirulence genes avrB and avrRpt2 from P. syringae pv. glycinea were examined. Psm4326 containing avirulent genes, avrB and avrRpt2 induced lignification and peroxidase activities in the bacteria infiltrated leaves of Col-O only and not in Mt-O, Bla-2 and Po-1. However, Arabidopsis ecotypes infiltrated with Psm4326 harboring with and without avirulent genes all showed differential induction of mRNA for peroxidase gene and lignin accumulation up to 24 h after infiltration. Only avrB gene in Col-O showed strong corelationship between peroxidase mRNA expression as well as lignification gradually up to 36 h after infiltration. These results extend previous observations that avirulence genes from pathogens of one host plant can be recognized by non-host plants and provide the genetic framework for analysis of the plant-specific response to the bacterial avirulent gene products in A. thaliana.
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Cardelino C, Chang M, St John J, Murphey B, Cordle J, Ballagas R, Patterson L, Powell K, Stogner J, Zimmer-Dauphinee S. Ozone predictions in Atlanta, Georgia: analysis of the 1999 ozone season. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2001; 51:1227-1236. [PMID: 11518297 DOI: 10.1080/10473289.2001.10464342] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Ozone prediction has become an important activity in many U.S. ozone nonattainment areas. In this study, we describe the ozone prediction program in the Atlanta metropolitan area and analyze the performance of this program during the 1999 ozone-forecasting season. From May to September, a team of 10 air quality regulators, meteorologists, and atmospheric scientists made a daily prediction of the next-day maximum 8-hr average ozone concentration. The daily forecast was made aided by two linear regression models, a 3-dimensional air quality model, and the no-skill ozone persistence model. The team's performance is compared with the numerical models using several numerical indicators. Our analysis indicated that (1) the team correctly predicted next-day peak ozone concentrations 84% of the time, (2) the two linear regression models had a better performance than a 3-dimensional air quality model, (3) persistence was a strong predictor of ozone concentrations with a performance of 78%, and (4) about half of the team's wrong predictions could be prevented with improved meteorological predictions.
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165
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Chang M, Hahn RA, Teutsch SM, Hutwagner LC. Multiple risk factors and population attributable risk for ischemic heart disease mortality in the United States, 1971–1992. J Clin Epidemiol 2001; 54:634-44. [PMID: 11377125 DOI: 10.1016/s0895-4356(00)00343-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The objective of this study was to assess the associations and population attributable risks (PAR) of risk factor combinations and ischemic heart disease (IHD) mortality in the United States. We used logistic regression models to assess the association of risk factors with IHD in the First National Health and Nutrition Examination Survey (1971-1974) and Epidemiologic Follow-up Study (1982-1992) among white and black men and women. We examined eight modifiable risk factors: hypertension, elevated serum cholesterol, diabetes, overweight, current smoking, physical inactivity, depression, and nonuse of replacement hormones. Risk factors associated with IHD mortality were the same among white and black men (i.e., age, education, smoking, diabetes, hypertension, and serum cholesterol). Age, education, smoking, diabetes, and hypertension were the risk factors among white and black women. Physical inactivity, nonuse of replacement hormones, serum cholesterol, and overweight were the additional risk factors among white women. Adjusted for demographic risk factors, overall PARs for study risk factors were 41.2% for white men, 60.5% for white women (with five risk factors only), 49.2% for black men, and 71.2% for black women. Much IHD mortality attributable to individual risk factors is caused by those factors in combination with other risk factors; relatively little mortality is attributable to each risk factor in isolation. Analysis that does not examine risk factor combinations may greatly overestimate PARs associated with individual risk factors.
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166
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Chang M, Shin YG, van Breemen RB, Blond SY, Bolton JL. Structural and functional consequences of inactivation of human glutathione S-transferase P1-1 mediated by the catechol metabolite of equine estrogens, 4-hydroxyequilenin. Biochemistry 2001; 40:4811-20. [PMID: 11294649 DOI: 10.1021/bi002513o] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The inactivation mechanism(s) of human glutathione S-transferase P1-1 (hGST P1-1) by the catechol metabolite of Premarin estrogens, 4-hydroxyequilenin (4-OHEN), was (were) studied by means of site-directed mutagenesis, electrospray ionization mass spectrometric analysis, titration of free thiol groups, kinetic studies of irreversible inhibition, and analysis of band patterns on nonreducing sodium dodecyl sulfate--polyacrylamide gel electrophoresis (SDS-PAGE). The four cysteines (Cys 14, Cys 47, Cys 101, and Cys 169 in the primary sequence) in hGST P1-1 are susceptible to electrophilic attack and/or oxidative damage leading to loss of enzymatic activity. To investigate the role of cysteine residues in the 4-OHEN-mediated inactivation of this enzyme, one or a combination of cysteine residues was replaced by alanine residues (C47A, C101A, C47A/C101A, C14A/C47A/C101A, and C47A/C101A/C169A mutants). Mutation of Cys 47 decreased the affinity for the substrate GSH but not for the cosubstrate 1-chloro-2,4-dinitrobenzene (CDNB). However, the Cys 47 mutation did not significantly affect the rate of catalysis since V(max) values of the mutants were similar or higher compared to that of wild type. Electrospray ionization mass spectrometric analyses of wild-type and mutant enzymes treated with 4-OHEN showed that a single molecule of 4-OHEN-o-quinone attached to the proteins, with the exception of the C14A/C47A/C101A mutant where no covalent adduct was detected. 4-OHEN also caused oxidative damage as demonstrated by the appearance of disulfide-bonded species on nonreducing SDS--PAGE and protection of 4-OHEN-mediated enzyme inhibition by free radical scavengers. The studies of thiol group titration and irreversible kinetic experiments indicated that the different cysteines have distinct reactivity for 4-OHEN; Cys 47 was the most reactive thiol group whereas Cys 169 was resistant to modification. These results demonstrate that hGST P1-1 is inactivated by 4-OHEN through two possible mechanisms: (1) covalent modification of cysteine residues and (2) oxidative damage leading to proteins inactivated by disulfide bond formation.
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Chang M, Shi Y, Nail SL, HogenEsch H, Adams SB, White JL, Hem SL. Degree of antigen adsorption in the vaccine or interstitial fluid and its effect on the antibody response in rabbits. Vaccine 2001; 19:2884-9. [PMID: 11282199 DOI: 10.1016/s0264-410x(00)00559-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The effect of the degree of adsorption of lysozyme by aluminium hydroxide adjuvant on the immune response in rabbits was studied. The surface charge of the adjuvant was modified by pretreatment with phosphate anion to produce five vaccines having degrees of adsorption ranging from 3 to 90%. The degree of adsorption of vaccines exhibiting 3, 35 or 85% adsorption changed to 40% within 1 h after each vaccine was mixed with sheep interstitial fluid to simulate subcutaneous administration. The mean anti-lysozyme antibody titers produced by the vaccines were the same and were four times greater than that produced by a lysozyme solution. Thus, the degree of adsorption of lysozyme in sheep interstitial fluid rather than the degree of adsorption in the vaccine correlated with the immune response.
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168
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Park H, Choi H, Lang J, Choi S, Rhee J, Chang M. Synthesis and in vitro antibacterial activity of cephalosporins with a pyridinium substituent carrying an isoxazole moiety at the C-3 position. Arch Pharm Res 2001; 24:89-94. [PMID: 11339638 DOI: 10.1007/bf02976473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Several quaternary pyridinium cephalosporin analogues were prepared and evaluated in vitro for antibacterial activity against selected gram-positive and gram-negative organisms. Most of the synthesized analogues were either as effective or less effective against the tested bacterial organisms than the reference compounds, Cefpirome and Ceftazidime.
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Chang M, Lubahn DB, Hoffman RW. DNA microsatellite markers for estrogen receptor-beta are not associated with systemic lupus erythematosus. J Rheumatol 2001; 28:924-5. [PMID: 11327282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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170
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Chang M, Walker SE, Hoffman RW. Immunization with a bacterial ATP-binding cassette transporter fragment suppresses autoimmunity and prolongs survival in MRL/lpr lupus-prone mice. Lupus 2001; 9:655-63. [PMID: 11199919 DOI: 10.1191/096120300667608330] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The present study was undertaken to better define the role of the U1 70 kDa antigen in a spontaneous murine model of systemic lupus erythematosus (SLE) by testing whether immunization with the U1 70 kDa polypeptide could alter the production of antibodies against U1 70 kDa or against other small nuclear ribonucleoproteins (snRNP), modify disease expression or alter survival. We found that, while immunization with a U1 70 kDa derived fusion protein (70 KFP) tended to delay the development of anti-snRNP antibodies in the sera of MRL/lpr mice, it had no effect on autoimmune-mediated renal disease or survival. Unexpectedly, it was found that MRL/lpr mice immunized with a 367 amino acid fragment of a bacterial ATP-binding cassette transporter, MFP, had prolonged survival compared to saline injection or U1 70 kDa immunization and that this was associated with a delay in the onset of SLE-like proliferative glomerulonephritis. This is the first study, to our knowledge, in which a bacterial ATP-binding cassette transporter was shown to be beneficial in treating a murine model of SLE. We report that MFP significantly prolonged longevity in the MRL/lpr murine model of SLE compared to saline injection or 70 KFP immunization and that improved survival was associated with a delay in the onset of SLE-like glomerulonephritis.
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Silverman GJ, Shaw PX, Luo L, Dwyer D, Chang M, Horkko S, Palinski W, Stall A, Witztum JL. Neo-self antigens and the expansion of B-1 cells: lessons from atherosclerosis-prone mice. Curr Top Microbiol Immunol 2001; 252:189-200. [PMID: 11125476 DOI: 10.1007/978-3-642-57284-5_20] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The pathogenesis of atherosclerosis involves an inflammatory process that is modulated by the immune system, and within these complex responses we have discerned a possible role for an archetypic B-1 clone. We speculate that due to their immunogenicity and in vivo distribution the "neo"-self determinants created in oxidatively modified LDL are highly stimulatory for certain B-1 cell clones. These neo-self determinants, which can be created chemically, by somatic processes, may in fact represent the molecular analogues of somatic maturation, or even aging. These changes, including those on non-protein antigens induced by oxidative metabolism, amongst others, create neo-determinants against which the host no doubt can not develop rigorous B-cell tolerance. The onset of expression of these oxidative neo-determinants relatively late in development may well serve a useful function for the highly evolved mammalian immune system, as targeting by evolutionarily selected B-1 clones may facilitate the amplification of other useful antibody-mediated physiologic functions. As in the case of the T15 clone, these antibodies may aid in protection against common microbial pathogens. Hence we postulate that during the evolution of the adaptive immune system the neo-self antigenic milieu may have been exploited for the natural selection of primordial clonal specificities. The T15 B-1 clone may then illustrate a common paradigm in which there has been natural selection based on utility for the defense of the individual from environmental threats, as well as for possible "housekeeping" role(s) and the maintenance of cellular homeostasis.
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Ryan SV, Dougherty MJ, Chang M, Lombardi J, Raviola C, Calligaro K. Abnormal duplex findings at the proximal anastomosis of infrainguinal bypass grafts: does revision enhance patency? Ann Vasc Surg 2001; 15:98-103. [PMID: 11221953 DOI: 10.1007/s100160010004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Using color duplex ultrasound (CDU) surveillance of autogenous infrainguinal bypasses, a peak systolic flow velocity (PSFV) ratio of greater than 3 to 1 within the graft relative to adjacent PSFV has been accepted as predicting significant stenosis mandating revision. At the proximal anastomosis, where significant vessel diameter differences and turbulent flow exist, the validity of these criteria is less clear. Our purpose was to review our experience with proximal anastomotic abnormalities in a CDU surveillance protocol. Routine CDU surveillance for all infrainguinal bypass gratis consisted of evaluation in an accredited vascular laboratory at 1 month postoperatively, every 3 months for the first year, every 6 months in the second year, and annually thereafter. Grafts with a PSFV ratio of >3 at the proximal anastomosis on any CDU study were included in this review. From our results we conclude that currently accepted CDU criteria for graft-threatening stenosis may not be valid for abnormalities at the proximal anastomosis of infrainguinal grafts. Regression of these abnormalities is common. Better CDU criteria are needed for predicting not only severity of proximal anastomotic stenosis but also likelihood of graft thrombosis.
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Chen JX, Berry LC, Tanner M, Chang M, Myers RP, Meyrick B. Nitric oxide donors regulate nitric oxide synthase in bovine pulmonary artery endothelium. J Cell Physiol 2001; 186:116-23. [PMID: 11147806 DOI: 10.1002/1097-4652(200101)186:1<116::aid-jcp1005>3.0.co;2-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
This study examined the notion that exogenous generation of nitric oxide (NO) modulates NOS gene expression and activity. Bovine pulmonary artery endothelial cells (BPAEC) were treated with the NO donors, 1 mM SNAP (S-nitroso-N-acetylpenicillamine), 0.5 mM SNP (sodium nitroprusside) or 0.2 microM NONOate (spermine NONOate) in medium 199 containing 2% FBS. Controls included untreated cells and cells exposed to 1 mM NAP (N-acetyl-D-penicillamine). NOS activity was assessed using a fibroblast-reporter cell assay; intracellular Ca2+ concentrations were assessed by Fura-2 microfluorometry; and NO release was measured by chemiluminescence. Constitutive endothelial (e) and inducible (i) NOS gene and protein expression were examined by northern and western blot analysis, respectively. Two hours exposure to either SNAP or NONOate caused a significant elevation in NO release from the endothelial cells (SNAP = 51.4 +/- 5.9; NONOate = 23.8 +/- 4.2; control = 14.5 +/- 2.8 microM); but A23187 (3 microM)-stimulated NO release was attenuated when compared to controls. Treatment with either SNAP or NONOate for 2 h also resulted in a significant increase in NOS activity in endothelial homogenates (SNAP = 23.6 +/- 2.5; NONOate= 29.8 +/- 7.7; control = 14.5 +/- 2.5fmol cGMP/microg per 10(6) cells). Exposure to SNAP and SNP, but not NONOate, for 1 h caused an increase in intracellular calcium. Between 4 and 8 h, SNAP and NONOate caused a 2- to 3-fold increase in eNOS, but not iNOS, gene (P < 0.05) and protein expression. NAP had little effect on either eNOS gene expression, activity or NO production. Our data indicate that exogenous generation of NO leads to a biphasic response in BPAEC, an early increase in intracellular Ca2+, and increases in NOS activity and NO release followed by increased expression of the eNOS gene, but not the iNOS gene. We conclude that eNOS gene expression and activity are regulated by a positive-feedback regulatory action of exogenous NO.
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Sterman DH, Molnar-Kimber K, Iyengar T, Chang M, Lanuti M, Amin KM, Pierce BK, Kang E, Treat J, Recio A, Litzky L, Wilson JM, Kaiser LR, Albelda SM. A pilot study of systemic corticosteroid administration in conjunction with intrapleural adenoviral vector administration in patients with malignant pleural mesothelioma. Cancer Gene Ther 2000; 7:1511-8. [PMID: 11228529 DOI: 10.1038/sj.cgt.7700269] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
One of the primary limitations of adenoviral (Ad) -mediated gene therapy is the generation of anti-Ad inflammatory responses that can induce clinical toxicity and impair gene transfer efficacy. The effects of immunosuppression on these inflammatory responses, transgene expression, and toxicity have not yet been systematically examined in humans undergoing Ad-based gene therapy trials. We therefore conducted a pilot study investigating the use of systemic corticosteroids to mitigate antivector immune responses. In a previous phase I clinical trial, we demonstrated that Ad-mediated intrapleural delivery of the herpes simplex virus thymidine kinase gene (HSVtk) to patients with mesothelioma resulted in significant, but relatively superficial, HSVtk gene transfer and marked anti-Ad humoral and cellular immune responses. When a similar group of patients was treated with Ad.HSVtk and a brief course of corticosteroids, decreased clinical inflammatory responses were seen, but there was no demonstrable inhibition of anti -Ad antibody production or Ad-induced peripheral blood mononuclear cell activation. Corticosteroid administration also had no apparent effect on the presence of intratumoral gene transfer. Although limited by the small numbers of patients studied, our data suggest that systemic administration of steroids in the context of Ad-based gene delivery may limit acute clinical toxicity, but may not inhibit cellular and humoral responses to Ad vectors.
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Pimentel M, Chang M, Chow EJ, Tabibzadeh S, Kirit-Kiriak V, Targan SR, Lin HC. Identification of a prodromal period in Crohn's disease but not ulcerative colitis. Am J Gastroenterol 2000; 95:3458-62. [PMID: 11151877 DOI: 10.1111/j.1572-0241.2000.03361.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Irritable bowel syndrome, a common gastrointestinal diagnosis, has not been clearly studied in inflammatory bowel disease. Some of the residual symptoms in subjects treated with Crohn's disease and ulcerative colitis are thought to be related to irritable bowel syndrome. The aims of this study were 1) to describe the duration and nature of complaints before the diagnosis of Crohn's disease and ulcerative colitis (prodromal period), and 2) to determine the role of IBS in this prodromal period. METHODS A total of 66 patients with confirmed inflammatory bowel disease were enrolled in the study. The subjects received a questionnaire to ascertain the nature and duration of symptoms preceding the diagnosis of Crohn's disease or ulcerative colitis, including features described under the Rome criteria for irritable bowel syndrome. RESULTS Of the 66 subjects analyzed, 45 had Crohn's disease and 21 had ulcerative colitis. The prodromal period was 7.7 +/- 10.7 yr for Crohn's disease and 1.2 +/- 1.8 yr for ulcerative colitis (p < 0.05). Once patients meeting the Rome criteria for irritable bowel syndrome during the prodrome were excluded, the duration of the prodromal period (non-IBS) for ulcerative colitis dropped to 0.8 +/- 1.3 yr compared to 6.9 +/- 9.8 yr in the Crohn's disease group (p < 0.05). The symptoms of the non-IBS prodrome in subjects with Crohn's disease were bloating, diarrhea, stomach pain, heartburn, fever, weight loss, and fatigue. Further analysis demonstrated that subjects whose Crohn's disease initially began as colonic disease had a longer prodrome than with small bowel. In the non-IBS Crohn's group, there was also a correlation between the age at the time of diagnosis and the duration of prodrome (r = 0.67, p < 0.0001). CONCLUSIONS There is a significant prodromal period before the time of diagnosis of Crohn's disease that is not found in ulcerative colitis even after exclusion of subjects with IBS.
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