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Suk K, Chang I, Kim YH, Kim S, Kim JY, Kim H, Lee MS. Interferon gamma (IFNgamma ) and tumor necrosis factor alpha synergism in ME-180 cervical cancer cell apoptosis and necrosis. IFNgamma inhibits cytoprotective NF-kappa B through STAT1/IRF-1 pathways. J Biol Chem 2001; 276:13153-9. [PMID: 11278357 DOI: 10.1074/jbc.m007646200] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We investigated the molecular mechanism of the synergism between interferon gamma (IFNgamma) and tumor necrosis factor alpha (TNFalpha) documented in a variety of biological occasions such as tumor cell death and inflammatory responses. IFNgamma/TNFalpha synergistically induced apoptosis of ME-180 cervical cancer cells. IFNgamma induced STAT1 phosphorylation and interferon regulatory factor 1 (IRF-1) expression. Transfection of phosphorylation-defective STAT1 inhibited IFNgamma/TNFalpha-induced apoptosis, whereas IRF-1 transfection induced susceptibility to TNFalpha. Dominant-negative IkappaBalpha transfection sensitized ME-180 cells to TNFalpha. IFNgamma pretreatment attenuated TNFalpha- or p65-induced NF-kappaB reporter activity, whereas it did not inhibit p65 translocation or DNA binding of NF-kappaB. IRF-1 transfection alone inhibited TNFalpha-induced NF-kappaB activity, which was reversed by coactivator p300 overexpression. Caspases were activated by IFNgamma/TNFalpha combination; however, caspase inhibition did not abrogate IFNgamma/TNFalpha-induced cell death. Instead, caspase inhibitors directed IFNgamma/TNFalpha-treated ME-180 cells to undergo necrosis, as demonstrated by Hoechst 33258/propidium iodide staining and electron microscopy. Taken together, our results indicate that IFNgamma and TNFalpha synergistically act to destroy ME-180 tumor cells by either apoptosis or necrosis, depending on caspase activation, and STAT1/IRF-1 pathways initiated by IFNgamma play a critical role in IFNgamma/TNFalpha synergism by inhibiting cytoprotective NF-kappaB. IFNgamma/TNFalpha synergism appears to activate cell death machinery independently of caspase activation, and caspase activation seems to merely determine the mode of cell death.
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Suk K, Kim YH, Chang I, Kim JY, Choi YH, Lee KY, Lee MS. IFNalpha sensitizes ME-180 human cervical cancer cells to TNFalpha-induced apoptosis by inhibiting cytoprotective NF-kappaB activation. FEBS Lett 2001; 495:66-70. [PMID: 11322949 DOI: 10.1016/s0014-5793(01)02335-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Tumor necrosis factor alpha (TNFalpha) induces apoptosis of a variety of tumor cell types. The anti-tumor effect of TNFalpha is often augmented by interferon (IFN) gamma. We hypothesized that IFNalpha, which shares many biological activities with IFNgamma, might also synergize with TNFalpha for the induction of tumor cell death. We tested our hypothesis using ME-180 human cervical cancer cells exposed to either IFNalpha or TNFalpha alone or both. We analyzed the death of ME-180 cells by biochemical and cytological means, and investigated the molecular mechanism underlying cytotoxic synergism between the two cytokines. We found that (i) IFNalpha/TNFalpha synergistically induced apoptosis of ME-180 cells, which was accompanied by activation of caspases-3 and -8; (ii) IFNalpha induced signal transducer and activator of transcription (STAT) 1 phosphorylation, and transfection of phosphorylation-defective STAT1 dominant-negative mutant inhibited IFNalpha/TNFalpha-induced apoptosis; (iii) inhibition of nuclear factor kappaB (NF-kappaB) by proteasome inhibitor MG-132 sensitized ME-180 cells to TNFalpha alone; (iv) IFNalpha treatment attenuated TNFalpha-induced NF-kappaB reporter activity, while it did not inhibit DNA binding of NF-kappaB. Taken collectively, our results indicate that IFNalpha sensitizes ME-180 cells to TNFalpha-induced apoptosis by inhibiting TNFalpha-mediated cytoprotective NF-kappaB activation, and this sensitizing effect of IFNalpha is mediated through a STAT1-dependent pathway.
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Suk K, Kim S, Kim YH, Kim KA, Chang I, Yagita H, Shong M, Lee MS. IFN-gamma/TNF-alpha synergism as the final effector in autoimmune diabetes: a key role for STAT1/IFN regulatory factor-1 pathway in pancreatic beta cell death. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:4481-9. [PMID: 11254704 DOI: 10.4049/jimmunol.166.7.4481] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Fas ligand (FasL), perforin, TNF-alpha, IL-1, and NO have been considered as effector molecule(s) leading to beta cell death in autoimmune diabetes. However, the real culprit(s) in beta cell destruction have long been elusive, despite intense investigation. We and others have demonstrated that FasL is not a major effector molecule in autoimmune diabetes, and previous inability to transfer diabetes to Fas-deficient nonobese diabetic (NOD)-lpr mice was due to constitutive FasL expression on lymphocytes from these mice. Here, we identified IFN-gamma/TNF-alpha synergism as the final effector molecules in autoimmune diabetes of NOD mice. A combination of IFN-gamma and TNF-alpha, but neither cytokine alone, induced classical caspase-dependent apoptosis in insulinoma and pancreatic islet cells. IFN-gamma treatment conferred susceptibility to TNF-alpha-induced apoptosis on otherwise resistant insulinoma cells by STAT1 activation followed by IFN regulatory factor (IRF)-1 induction. IRF-1 played a central role in IFN-gamma/TNF-alpha-induced cytotoxicity because inhibition of IRF-1 induction by antisense oligonucleotides blocked IFN-gamma/TNF-alpha-induced cytotoxicity, and transfection of IRF-1 rendered insulinoma cells susceptible to TNF-alpha-induced cytotoxicity. STAT1 and IRF-1 were expressed in pancreatic islets of diabetic NOD mice and colocalized with apoptotic cells. Moreover, anti-TNF-alpha Ab inhibited the development of diabetes after adoptive transfer. Taken together, our results indicate that IFN-gamma/TNF-alpha synergism is responsible for autoimmune diabetes in vivo as well as beta cell apoptosis in vitro and suggest a novel signal transduction in IFN-gamma/TNF-alpha synergism that may have relevance in other autoimmune diseases and synergistic anti-tumor effects of the two cytokines.
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MESH Headings
- Animals
- Apoptosis/immunology
- Autoimmune Diseases/immunology
- Autoimmune Diseases/pathology
- Autoimmune Diseases/prevention & control
- Caspase 1/biosynthesis
- Caspases/biosynthesis
- Caspases, Initiator
- Cell Death/immunology
- Cells, Cultured
- Cytotoxicity Tests, Immunologic
- DNA-Binding Proteins/biosynthesis
- DNA-Binding Proteins/metabolism
- DNA-Binding Proteins/physiology
- Diabetes Mellitus, Type 1/immunology
- Diabetes Mellitus, Type 1/pathology
- Diabetes Mellitus, Type 1/prevention & control
- Drug Synergism
- Enzyme Induction/immunology
- Immune Sera/administration & dosage
- Infusions, Intravenous
- Interferon Regulatory Factor-1
- Interferon-gamma/toxicity
- Islets of Langerhans/immunology
- Islets of Langerhans/metabolism
- Islets of Langerhans/pathology
- Mice
- Mice, Inbred ICR
- Mice, Inbred NOD
- Phosphoproteins/biosynthesis
- Phosphoproteins/metabolism
- Phosphoproteins/physiology
- Phosphorylation
- STAT1 Transcription Factor
- Signal Transduction/immunology
- Trans-Activators/metabolism
- Trans-Activators/physiology
- Tumor Cells, Cultured
- Tumor Necrosis Factor-alpha/antagonists & inhibitors
- Tumor Necrosis Factor-alpha/immunology
- Tumor Necrosis Factor-alpha/toxicity
- Up-Regulation/immunology
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Chang I, Lapham SC, Wanberg KW. Alcohol use inventory: screening and assessment of first-time driving-while-impaired offenders. I. Reliability and profiles. Alcohol Alcohol 2001; 36:112-21. [PMID: 11259207 DOI: 10.1093/alcalc/36.2.112] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This study evaluated the use of the Alcohol Use Inventory (AUI) in a drink-driving offender population court-mandated to attend a screening programme. We compared offenders' scale scores, reliability statistics and profiles to those from two clinical populations on which the AUI was normed. Among offenders, males and females had similar levels of involvement with alcohol, and Native Americans had higher scale scores than other ethnic groups. Comparisons with the normative population revealed lower mean scale scores and lower reliability scores among offenders. Differences between the offender and normative populations were most pronounced for the primary scales. We also found inconsistencies in offenders' responses to certain questions. To address this, we recommend that, when using the AUI for screening offenders: (1) screeners place more emphasis on second- and third-order scales than primary scales; (2) lower cut-off points be used for identifying problem drinkers; (3) counsellors conduct in-person interviews with clients to develop rapport and encourage self-disclosure.
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Chang I, Lapham SC, C'de Baca J, Davis JW. Alcohol use inventory: screening and assessment of first-time driving-while-impaired offenders. II. Typology and predictive validity. Alcohol Alcohol 2001; 36:122-30. [PMID: 11259208 DOI: 10.1093/alcalc/36.2.122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
This study evaluated the use of Alcohol Use Inventory (AUI) for driving-while-impaired (DWI) screening, by determining whether DWI offenders (n = 1644), grouped according to their reported alcohol involvement on the AUI, would have different rates of recidivism in a 5-year follow-up. Cluster analysis using the six second-order scales produced six groups (clusters 1-6) described as the Low-Profile (50%), Alcohol-Preoccupation (14%), Enhanced (22%), Enhanced-Disrupt (9%), Anxious-Disrupt (3%), and High-Profile (1%) types. They were characterized by different sociodemographic profiles. Members of cluster 4 were associated with the highest DWI recidivism rate (40%), committing one or more further DWI, and clusters 5 and 6 were associated with the highest rate of committing two or more DWIs. Rates of subsequent traffic convictions and crashes were, however, not statistically different among the clusters. Predictors of DWI recidivism included male gender, young age, less-educated, high blood-alcohol concentration at arrest, and clusters of 3 and 4. Different typologies indicated that the needs for treatment might be different. Evaluators should keep in mind the strength of AUI, use risk factors identified in the study, and take measures of test-taking defensiveness to enhance overall predictive validity.
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Rennels MB, Edwards KM, Keyserling HL, Reisinger K, Blatter MM, Quataert SA, Madore DV, Chang I, Malinoski FJ, Hackell JG, Paradiso PR. Safety and immunogenicity of four doses of Neisseria meningitidis group C vaccine conjugated to CRM197 in United States infants. Pediatr Infect Dis J 2001; 20:153-9. [PMID: 11224833 DOI: 10.1097/00006454-200102000-00007] [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: 11/26/2022]
Abstract
BACKGROUND Following widespread use of conjugate pneumococcal vaccine, Neisseria meningitidis likely will become the leading cause of bacterial sepsis and meningitis in US children. This report describes the safety and immunogenicity in US children of four consecutive doses of a meningococcal group C vaccine conjugated to CRM197 via reductive amination (MnCC). METHODS One hundred six healthy 2-month-old infants received MnCC at 2, 4 and 6 months of age in a randomized, controlled double blind study; children in the other treatment arm were given a 7-valent conjugate pneumococcal vaccine. Parents reenrolled 64 of these children at 12 to 15 months to receive a fourth dose of MnCC. Routine childhood vaccines, including DTP, were coadministered. Temperatures and symptoms were recorded for 3 days after each immunization. Serum enzyme-linked immunosorbent assay IgG and bactericidal antibodies were measured prevaccination and before and 1 month after Doses 3 and 4. RESULTS Moderate to severe local reactions, defined as erythema or induration > or =2.4 cm or pain that interfered with limb movement was reported after 0 to 3.2% of MnCC injections, depending on the reaction and dose. Fever occurred in 23 to 37% of children, but the contribution of MnCC to the febrile reactions is unknown. Geometric mean concentrations of IgG antibody to group C meningococcal polysaccharide were 3.72 microg/ml after Dose 3 and 8.03 microg/ml after the booster. Geometric mean functional serum bactericidal antibody titers after Doses 3 and 4 were 1:463 and 1:2341, respectively. One hundred percent of children had a serum bactericidal antibody titer of > or =1:64 after three doses and > or = 1:128 after the booster. CONCLUSIONS The MnCC vaccine had an acceptable safety profile and generated high titers of bactericidal antibody in immunized US infants and toddlers. It appears to be an attractive candidate vaccine for the prevention of serogroup C meningococcal disease in young children.
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Lapham SC, Skipper BJ, Hunt WC, Chang I. Do risk factors for re-arrest differ for female and male drunk-driving offenders? Alcohol Clin Exp Res 2000; 24:1647-55. [PMID: 11104112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
BACKGROUND The present study investigated gender differences in factors affecting recidivism among 628 female and 659 male drunk-driving offenders. The study population included residents from New Mexico who completed a screening program for offenders and who were still residents when contacted 5 years later. METHOD Risk factors for re-arrest in the 5-year period after screening referral were examined using multiple logistic regression models. Predictor variables included gender, age, ethnicity, education, marital status, blood alcohol concentration at arrest, parental alcohol problems, spousal alcohol problems, lifetime use of cannabis, cocaine, or amphetamines, abusive behavior toward spouse, and scores on two standardized assessments. RESULTS Risk factors for re-arrest were similar for males and females except that young age predicted higher recidivism among males but not females. The overall 5-year re-arrest rate was 26%-20% for women, 38% for males age 30 and under, and 24% for males age 31 and older. CONCLUSIONS Young age predicts re-arrest for males but not for females. Neither the type of risk factors nor the number of risk factors fully explained female offenders' disproportionately lower recidivism rates, compared with young males.
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Lapham S, Baum G, Skipper B, Chang I. Attrition in a follow-up study of driving while impaired offenders: who is lost? Alcohol Alcohol 2000; 35:464-70. [PMID: 11022021 DOI: 10.1093/alcalc/35.5.464] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
High attrition rates seriously threaten the validity of follow-up studies of criminal justice populations. This study examines attrition from a follow-up study of drink-driving offenders referred 5 years earlier to a screening programme. The aim of the study was to determine which factors are most closely associated with: (1) inability to locate subjects, (2) subjects' refusal to participate; (3) the manner in which subjects refuse. Logistic regression models compared the following groups of subjects: located vs not located; interviewed vs not interviewed; type of refusal (direct vs indirect). Independent variables included gender, age group, ethnicity, whether the subject had a telephone, compliance with and completion of the screening programme, alcohol dependence or abuse diagnosis vs no diagnosis, breath-alcohol level (BAL) at the time of arrest, and whether the subject had an outstanding arrest warrant. Some factors (younger age, screening compliance, Mexican national ethnicity, and having an outstanding arrest warrant) predicted both inability to locate and type of refusal. Hispanic ethnicity and having a telephone predicted better success with locating subjects. Among refusers, non-Hispanic whites were more likely than other ethnic groups to refuse directly, and those with warrants were more likely to refuse indirectly. Non-compliance with the screening programme was also associated with differential follow-up rates. Neither arrest BAL nor alcohol diagnoses was associated with differential rates of follow-up. We conclude that alcohol diagnosis does not appear to influence successful follow-up in this criminal justice population. Rather, tracking and interviewing challenges differed among ethnic groups, suggesting a need for culturally sensitive recruitment strategies in these populations.
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Tracey I, Becerra L, Chang I, Breiter H, Jenkins L, Borsook D, González RG. Noxious hot and cold stimulation produce common patterns of brain activation in humans: a functional magnetic resonance imaging study. Neurosci Lett 2000; 288:159-62. [PMID: 10876085 DOI: 10.1016/s0304-3940(00)01224-6] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We used functional magnetic resonance imaging (fMRI) to determine whether similar brain regions activate during noxious hot and cold stimulation. Six male subjects underwent whole brain fMRI during phasic delivery of noxious hot (46 degrees C) and noxious cold (5 degrees C) stimulation to the dorsum of the left hand. Mid-brain regions activated included thalamus, basal ganglia and insula. Cortical areas activated included cingulate, somatosensory, premotor and motor cortices, as well as prefrontal and inferior parietal cortex. Most regions activated bilaterally but with stronger activation contralateral to the stimulus. Noxious cold stimulation produced significantly increased volumes of activation compared to noxious heat in prefrontal areas only. Our results suggest a similar network of regions activate common to the perception of pain produced by either noxious hot or cold stimulation.
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Lapham SC, Chang I, Gregory C. Substance abuse intervention for health care workers: a preliminary report. J Behav Health Serv Res 2000; 27:131-43. [PMID: 10795124 DOI: 10.1007/bf02287308] [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: 11/25/2022]
Abstract
The Workplace Managed Care Cooperative Agreement project targets 3,300 health care professionals in hospital, specialty clinic, and primary care settings located in metropolitan New Mexico communities. This project will evaluate whether enhancements to existing substance abuse prevention/early intervention programs can prevent the onset of risky drinking, reduce prevalence of risky drinking, better identify employees who abuse alcohol and drugs, and improve employee wellness. This article describes one such enhancement (Project WISE [Workplace Initiative in Substance Education]), implemented at Lovelace Health Systems. Project WISE includes relatively low-cost elements such as substance abuse awareness training, information on how to reduce drinking, and brief motivational counseling. Evaluation will consist of baseline comparisons of the intervention and comparison sites, a process evaluation, a qualitative analysis using focus groups, and an outcome evaluation using health and work records. Methodological challenges, solutions, and implications for researchers undertaking similar projects are presented.
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Obaro SK, Adegbola RA, Chang I, Banya WA, Jaffar S, Mcadam KW, Greenwood BM. Safety and immunogenicity of a nonavalent pneumococcal vaccine conjugated to CRM197 administered simultaneously but in a separate syringe with diphtheria, tetanus and pertussis vaccines in Gambian infants. Pediatr Infect Dis J 2000; 19:463-9. [PMID: 10819345 DOI: 10.1097/00006454-200005000-00014] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
BACKGROUND Unrelenting high morbidity and mortality have mandated that immunogenic vaccines be used to combat pneumococcal disease in infants. OBJECTIVES To evaluate the safety and immunogenicity of a nonavalent pneumococcal conjugate vaccine and the antigenic interaction when administered simultaneously with diphtheria, tetanus and pertussis vaccines. METHODS Two hundred seven infants were randomized to receive three doses of either nonavalent protein conjugate pneumococcal vaccine (PnCV) or inactivated polio vaccine (IPV) at 2, 3 and 4 months of age with routine Expanded Program of Immunization vaccines as scheduled. Vaccinees were visited on Days 1, 2 and 7 to observe local and systemic adverse reactions. Blood was drawn before the first dose and 1 month after the third dose. Antibody concentrations in sera were measured by standardized enzyme-linked immunosorbent assay. Nasopharyngeal carriage of pneumococci was tested at 5 and 9 months of age. RESULTS No serious reactions were observed. Local induration and tenderness were observed more commonly at the site of administration of diphtheria, tetanus and pertussis vaccines than at the site of administration of IPV or PnCV. Between 79 and 91% achieved >1 microg/ml antibody against specific pneumococcal serotypes. Antibody responses to diphtheria and pertussis antigens were similar in both groups; however, antibody response to tetanus toxoid was significantly lower in infants who received PnCV (geometric mean concentration, 11.1 vs. 17.4; P < 0.001). Nasopharyngeal carriage in PnCV-vaccinated children was reduced but not significantly different from those vaccinated with IPV. CONCLUSION Simultaneous administration of PnCV with Expanded Program of Immunization vaccines is safe and immunogenic. immune response to the composite antigens is likely to confer protection.
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Black S, Shinefield H, Fireman B, Lewis E, Ray P, Hansen JR, Elvin L, Ensor KM, Hackell J, Siber G, Malinoski F, Madore D, Chang I, Kohberger R, Watson W, Austrian R, Edwards K. Efficacy, safety and immunogenicity of heptavalent pneumococcal conjugate vaccine in children. Northern California Kaiser Permanente Vaccine Study Center Group. Pediatr Infect Dis J 2000; 19:187-95. [PMID: 10749457 DOI: 10.1097/00006454-200003000-00003] [Citation(s) in RCA: 1513] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE To determine the efficacy, safety and immunogenicity of the heptavalent CRM197 pneumococcal conjugate vaccine against invasive disease caused by vaccine serotypes and to determine the effectiveness of this vaccine against clinical episodes of otitis media. METHODS The Wyeth Lederle Heptavalent CRM197 (PCV) was given to infants at 2, 4, 6 and 12 to 15 months of age in a double blind trial; 37,868 children were randomly assigned 1:1 to receive either the pneumococcal conjugate vaccine or meningococcus type C CRM197 conjugate. The primary study outcome was invasive disease caused by vaccine serotype. Other outcomes included overall impact on invasive disease regardless of serotype, effectiveness against clinical otitis media visits and episodes, impact against frequent and severe otitis media and ventilatory tube placement. In addition the serotype-specific efficacy against otitis media was estimated in an analysis of spontaneously draining ears. RESULTS In the interim analysis in August, 1998, 17 of the 17 cases of invasive disease caused by vaccine serotype in fully vaccinated children and 5 of 5 of partially vaccinated cases occurred in the control group for a vaccine efficacy of 100%. Blinded case ascertainment was continued until April, 1999. As of that time 40 fully vaccinated cases of invasive disease caused by vaccine serotype had been identified, all but 1 in controls for an efficacy of 97.4% (95% confidence interval, 82.7 to 99.9%), and 52 cases, all but 3 in controls in the intent-to-treat analysis for an efficacy of 93.9% (95% confidence interval, 79.6 to 98.5%). There was no evidence of any increase of disease caused by nonvaccine serotypes. Efficacy for otitis media against visits, episodes, frequent otitis and ventilatory tube placement was 8.9, 7.0, 9.3 and 20.1% with P < 0.04 for all. In the analysis of spontaneously draining ears, serotype-specific effectiveness was 66.7%. CONCLUSION This heptavalent pneumococcal conjugate appears to be highly effective in preventing invasive disease in young children and to have a significant impact on otitis media.
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Mbelle N, Huebner RE, Wasas AD, Kimura A, Chang I, Klugman KP. Immunogenicity and impact on nasopharyngeal carriage of a nonavalent pneumococcal conjugate vaccine. J Infect Dis 1999; 180:1171-6. [PMID: 10479145 DOI: 10.1086/315009] [Citation(s) in RCA: 355] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The safety, immunogenicity, and impact on carriage of a nonvalent pneumococcal vaccine given at ages 6, 10, and 14 weeks were examined in a double-blind, randomized, placebo-controlled trial in 500 infants in Soweto, South Africa. No serious local or systemic side effects were recorded. Significant antibody responses to all pneumococcal serotypes were observed 4 weeks after the third dose. Haemophilus influenzae type b polyribosylribitol phosphate (geometric mean titer, 11.62 microg/mL) and diphtheria (1.39 IU/mL) antibodies were significantly higher in children receiving pneumococcal conjugate, compared with placebo recipients (4.58 microgram/mL and 0.98 IU/mL, respectively). Nasopharyngeal carriage of vaccine serotypes decreased in vaccinees at age 9 months (18% vs. 36%), whereas carriage of nonvaccine serotypes increased (36% vs. 25%). Carriage of penicillin-resistant pneumococci (21% vs. 41%) and cotrimoxazole-resistant pneumococci (23% vs. 35%) were significantly reduced 9 months after vaccination, compared with controls.
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Schwartzman D, Chang I, Michele JJ, Mirotznik MS, Foster KR. Electrical impedance properties of normal and chronically infarcted left ventricular myocardium. J Interv Card Electrophysiol 1999; 3:213-24. [PMID: 10490477 DOI: 10.1023/a:1009887306055] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Previous reports have disclosed that a significant difference exists between the electrical impedance properties of healthy and chronically infarcted ventricular myocardium. PURPOSE To assess the potential utility of electrical impedance as the basis for mapping in chronically infarcted left ventricular myocardium. Specifically: (1) to delineate electrical impedance properties of healthy and chronically infarcted ventricular myocardium, with special emphasis on the infarction border zone; (2) to correlate impedance properties with tissue histology; (3) to correlate impedance properties with electrogram amplitude and duration; (4) To demonstrate that endocardial impedance can be measured effectively in vivo using an electrode mounted on a catheter inserted percutaneously. METHODS An ovine model of chronic left ventricular infarction was utilized. Sites of healthy myocardium, densely infarcted myocardium and the infarction border zone were investigated. Bulk impedance was measured in vitro using capacitor cell, four-electrode and unipolar techniques. Epicardial and endocardial impedances were measured in vivo using four-electrode and unipolar techniques. Impedance was measured at multiple frequencies. Electrographic amplitude, duration and amplitude/duration ratio were measured using bipolar electrograms during sinus rhythm. Quantitation of tissue content of myocytes, collagen, elastin and neurovascular elements was performed. RESULTS Densely infarcted myocardial impedance was significantly lower than healthy myocardium. Impedance gradually decreased in the border zone transitioning between healthy myocardium and dense infarction. Decreasing impedance correlated with a decrease in tissue myocyte content. The magnitude of the difference in impedance between densely infarcted and healthy myocardium increased as the measurement frequency decreased. Healthy myocardium exhibited a marked frequency dependence in its impedance properties; this phenomenon was not observed in densely infarcted myocardium. There was a direct association between impedance and both electrogram amplitude and amplitude/duration ratio. There was an inverse association between impedance and electrogram duration. Endocardial impedance, measured in vivo using a electrode catheter inserted percutaneously, was demonstrated to distinguish between healthy and infarcted myocardium. CONCLUSIONS The electrical impedance properties of healthy and infarcted left ventricular myocardium differ markedly. The properties of the infarction border zone are intermediate between healthy and infarcted myocardium. Impedance may be a useful assay of cardiac tissue content and adaptable for cardiac mapping in vivo. Condensed Abstract. To delineate the electrical impedance properties of healthy and chronically infarcted left ventricular myocardium emphasizing the infarction border zone, impedance was measured in chronically infarcted ovine hearts. Densely infarcted myocardial impedance was significantly lower than healthy myocardium. Impedance gradually decreased in the infarction border zone in transition between healthy myocardium and dense infarction. This correlated with a decreasing myocyte content. The magnitude of the difference in impedance between densely infarcted and healthy myocardium increased as measurement frequency decreased. There was a direct association between impedance and electrogram characteristics. Endocardial impedance, measured in vivo using an electrode catheter inserted percutaneously, distinguished between healthy and infarcted myocardium
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Ryu J, Youn J, Kim Y, Kwon O, Song Y, Kim H, Cho K, Chang I. Mutation spectrum of 4-nitroquinoline N-oxide in the lacI transgenic Big Blue Rat2 cell line. Mutat Res 1999; 445:127-35. [PMID: 10521698 DOI: 10.1016/s1383-5718(99)00136-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This paper describes the spectrum of mutations induced by 4-nitroquinoline N-oxide (4-NQO) in the lacI target gene of the transgenic Big Blue Rat2 cell line. There are only a few report for the mutational spectrum of 4-NQO in a mammalian system although its biological and genetic effects have been well studied. Big Blue Rat2 cells were treated with 0.03125, 0.0625 or 0.125 microg/ml of 4-NQO, the highest concentration giving 85% survival. Our results indicated that the mutant frequency (MF) induced by 4-NQO was dose-dependent with increases from three- to seven-fold. The DNA sequence analysis of lacI mutants from the control and 4-NQO treatment groups revealed an obvious difference in the spectra of mutations. In spontaneous mutants, transition (60%) mutations, especially G:C-->A:T transition (45%), were most frequent. However, the major type of base substitution after treatment of 4-NQO was transversions (68.8%), especially G:C-->T:A (43.8%), while only 25% of mutants were transitions. These results are consistent with those produced by 4-NQO in other systems and the transgenic assay system will be a powerful tool to postulate more accurately the mechanism of chemical carcinogenesis involved.
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Shinefield HR, Black S, Ray P, Chang I, Lewis N, Fireman B, Hackell J, Paradiso PR, Siber G, Kohberger R, Madore DV, Malinowski FJ, Kimura A, Le C, Landaw I, Aguilar J, Hansen J. Safety and immunogenicity of heptavalent pneumococcal CRM197 conjugate vaccine in infants and toddlers. Pediatr Infect Dis J 1999; 18:757-63. [PMID: 10493334 DOI: 10.1097/00006454-199909000-00004] [Citation(s) in RCA: 208] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES The objectives of this study were (1) to determine the safety and immunogenicity of heptavalent pneumococcal CRM197 conjugate (PNCRM7) vaccine in infants and (2) to determine the effect of concurrent hepatitis B immunization during the primary series and the effect of concurrent diphtheria and tetanus toxoid and acellular pertussis [DTaP (ACEL-IMUNE)] and conjugate CRM197 Haemophilus influenzae type b [HbOC (HibTITER) immunization at time of the booster dose on the safety and immunogenicity of PNCRM7and these other concurrently administered vaccines. METHODS This was a randomized double-blinded study in 302 healthy infants in the Northern California Kaiser Permanente (NCKP) Health Plan. Infants received either PNCRM7 vaccine or meningococcal group C conjugate vaccine as a control at 2, 4 and 6 months of age and a booster at 12 to 15 months of age. Study design permitted the evaluation of immunology and safety of concurrent administration of routine vaccines. Antibody titers were determined on blood samples drawn before and 1 month after the primary series and the booster dose. RESULTS After the third dose of PNCRM7 geometric mean concentrations (GMCs) ranged from 1.01 for serotype 9V to 3.72 microg/ml for serotype 14. More than 90% of all subjects had a post-third dose titer of > or =0.15 microg/ml for all serotypes, and the percentage of infants with a post-third dose titer of > or =1.0 microg/ml ranged from 51% for type 9V to 89% for type 14. After the PNCRM7 booster dose, the GMCs of all seven serotypes increased significantly over both post-Dose 3 and pre-Dose 4 antibody levels. In the primary series there were no significant differences in GMCs of pneumococcal antibodies between the subjects given PN-CRM7 alone or concurrently with hepatitis B vaccine. At the toddler dose concurrent administration of PNCRM7 and DTaP and HbOC resulted in a near conventional threshold for statistical significance of a post-Dose 4 GMC for serotype 23F [alone 6.75 mirog/ml vs. concurrent 4.11 microg/ml (P = 0.057)] as well as significantly lower antibody GMCs for H. influenza polyribosylribitol phosphate, diphtheria toxoid, pertussis toxin and filamentous hemagglutinin. For all antigens there were no differences between study groups in defined antibody titers that are considered protective. CONCLUSION We conclude that PNCRM7 vaccine was safe and immunogenic. When this vaccine was administered concurrently at the booster dose with DTaP and HbOC vaccines, lower antibody titers were noted for some of the antigens when compared with the antibody response when PNCRM7 was given separately. Because the GMCs of the booster responses were all generally high and all subjects achieved similar percentages above predefined antibody titers, these differences are probably not clinically significant.
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Abstract
Although many studies have been published concerning clinical telemedicine, little information is available about emergency department (ED)-based telemedicine programs. An ED-based telemedicine program was initiated in April 1996 involving the National Cheng Kung University Hospital (NCKUH) and the Provincial Peng-Hu Hospital (PPHH) under a pilot project supported by the Department of Health. This is the first telemedicine program for remote offshore island service in Taiwan. The program is synchronous in nature to the practice of telemedicine. The role of the emergency physician includes giving initial suggestions, arranging consultations, coordination, and the organization of other medical tasks, such as accompanying some of the transfers. During the 12-month period, this system was used in 275 consultations, including 24 specialty and/or subspecialty department/sections, and more than 100 members of the medical staff have participated in this project since. In a survey, 89.4% of physicians in the PPHH and 82.2% of the physicians in NCKUH rated the system as very comfortable to work with and satisfactory. According to these observations, an ED-based telemedicine program is a feasible method for carrying out remote consultations. Successful development of the partnership and program of telemedicine is based on the active participation and coordination of the medical personnel and technicians between the cooperating hospitals.
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Cheon M, Heo M, Chang I, Stauffer D. Fragmentation of percolation clusters in general dimensions. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1999; 59:R4733-6. [PMID: 11969506 DOI: 10.1103/physreve.59.r4733] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/1998] [Indexed: 04/18/2023]
Abstract
The scaling behavior for binary fragmentation of critical percolation clusters in general dimensions is investigated by Monte Carlo simulation as well as by exact series expansions. We obtain values of critical exponents lambda and phi describing the scaling of the fragmentation rate and the distribution of cluster masses produced by binary fragmentation. Our results for lambda and phi in two to nine dimensions agree with the conjectured scaling relation sigma=1+lambda-phi by Edwards and co-workers [Phys. Rev. Lett. 68, 2692 (1992); Phys. Rev. A 46, 6252 (1992)], which in turn excludes the other scaling relations suggested by Gouyet (for d=2), and by Roux and Guyon [J. Phys. A 22, 3693 (1989)], where sigma is the crossover exponent for the cluster numbers in percolation theory.
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Tracey I, Hamberg LM, Guimaraes AR, Hunter G, Chang I, Navia BA, González RG. Increased cerebral blood volume in HIV-positive patients detected by functional MRI. Neurology 1998; 50:1821-6. [PMID: 9633734 DOI: 10.1212/wnl.50.6.1821] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To study changes in cerebral hemodynamics related to HIV infection. BACKGROUND Cerebral injury is a well-known manifestation of HIV infection. Physiologic changes in the HIV brain may precede structural changes and may be detected by functional MRI (fMRI). METHODS Dynamic contrast fMRI was used to measure the cerebral blood volume (CBV) in 13 patients infected with HIV and in 7 healthy control subjects. RESULTS Significant increases in dynamic CBV were found in the deep (p < 0.001) and cortical gray matter (p < 0.05) of HIV-positive (HIV+) patients. Patients with definite cognitive impairment showed significantly greater increases in CBV in the deep gray matter (DGM) compared with those without impairment. In one patient with rapidly progressive cognitive impairment, these abnormalities reversed and paralleled clinical improvement after initiation of zidovudine monotherapy. CONCLUSIONS This study supports the hypothesis that HIV infection is associated with significant cerebral hemodynamic changes, particularly in the DGM, that may contribute to cognitive dysfunction in AIDS. Functional MRI may be useful for early detection of cerebral injury and for the assessment of novel therapies.
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Rennels MB, Edwards KM, Keyserling HL, Reisinger KS, Hogerman DA, Madore DV, Chang I, Paradiso PR, Malinoski FJ, Kimura A. Safety and immunogenicity of heptavalent pneumococcal vaccine conjugated to CRM197 in United States infants. Pediatrics 1998; 101:604-11. [PMID: 9521941 DOI: 10.1542/peds.101.4.604] [Citation(s) in RCA: 271] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE To determine the safety and immunogenicity of heptavalent pneumococcal saccharide vaccine (serotypes 4, 6B, 9V, 14, 18C, 19F, 23F) individually conjugated to CRM197 (PNCRM7), administered at 2, 4, 6, and 12 to 15 months of age. DESIGN Two hundred twelve healthy 2-month-old infants were equally randomized to receive four consecutive doses of PNCRM7 or an investigational meningococcal group C conjugate vaccine, which served as a control. Concomitantly administered routine vaccines were oral polio vaccine and combined diphtheria toxoid, tetanus toxoid, and whole cell pertussis vaccine/Haemophilus influenzae type b vaccine consisting of capsular oligosaccharides conjugated to CRM197 (DTP/HbOC) at 2, 4, and 6 months, and either measles-mumps-rubella vaccine or HbOC at 12 to 15 months. Active safety surveillance was conducted for 3 days after each dose. Antibody concentrations to each of the 7 pneumococcal serotypes were measured by enzyme-linked immunosorbent assay prevaccination, after doses two and three, prebooster, and postbooster. RESULTS Significantly fewer children experienced local reactions at the PNCRM7 injection site than at the DTP/HbOC site. There was no increase in the incidence or severity of local reactions at the PNCRM7 site with increasing doses of vaccine. Mild to moderate postvaccination fever was common in both the PNCRM7 and control vaccine groups, however DTP/HbOC was administered concurrently. All 7 vaccine serotypes were immunogenic. The kinetics of the immune responses were serotype-specific. After three doses of PNCRM7, between 92% to 100% of children had >/=0.15 microg/mL of antibody, and 51% to 90% achieved a level of >/=1 microg/mL against specific serotypes. A booster dose of PNCRM7 resulted in a brisk anamnestic response to all 7 vaccine serotypes, demonstrating effective stimulation of T-cell memory by the primary series of vaccinations. CONCLUSION Primary immunization followed by a booster dose of PNCRM7 seemed to be acceptably safe and resulted in significant rises in antibody to all 7 serotypes. Implications. Studies to assess vaccine efficacy of PNCRM7 for prevention of systemic disease, nasopharyngeal colonization, and acute otitis media are in progress. If PNCRM7 proves to be protective, there is the potential to prevent up to 85% of invasive pneumococcal disease occurring in US children.
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Lapham SC, Skipper BJ, Chang I, Barton K, Kennedy R. Factors related to miles driven between drinking and arrest locations among convicted drunk drivers. ACCIDENT; ANALYSIS AND PREVENTION 1998; 30:201-206. [PMID: 9450123 DOI: 10.1016/s0001-4575(97)00084-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The objectives of the study were to estimate the distance driven between drinking and arrest locations among 3,107 offenders convicted of driving while impaired and to determined whether the drinking location, the driver's appearance (factors such as race, age, gender), or age of the vehicle account for any differences in the estimated distance driven. Statistical models were used to determine odds ratios for being arrested in the immediate vicinity of the drinking location, and for miles driven impaired. The independent sociodemographic and arrest variables included: age, gender, ethnicity/race, vehicle age, drinking location, whether the arrest followed a crash, time of arrest, blood alcohol concentration, and drinking in areas with varying levels of arrest intensity. The variables associated with arrest in the immediate vicinity of the drinking location (less than one half mile) were drinking in high or medium-high arrest intensity areas, Hispanic/Mexican ethnicity/nationality, Native American race, and drinking at home. Among those who were not arrested in the immediate vicinity, the number of miles driven ranged from 0.5 to 18.2, with a mean of 3.4 miles (median = 2.6). Analysis of covariance demonstrated that among those arrested outside the immediate vicinity of their drinking locations, persons who drank in a high or medium-high arrest intensity area, those with blood alcohol concentrations of > or = 200 mg/l, and those drinking at bars, restaurants, or private parties, drove fewer miles compared to other offenders. Our findings are mixed regarding ethnicity/race. Traits such as age, gender, and vehicle age are unrelated to how far drunk drivers travel before their arrests.
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King JC, Vink PE, Chang I, Kimura A, Parks M, Smilie M, Lichenstein R, Farley JJ. Antibody titers eight months after three doses of a five-valent pneumococcal conjugate vaccine in HIV and non-HIV-infected children less than two years of age. Vaccine 1998; 16:361-5. [PMID: 9607056 DOI: 10.1016/s0264-410x(97)80914-0] [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: 02/07/2023]
Abstract
The objective of this study was to examine vaccine type-specific antibody titers eight months after a five-valent pneumococcal conjugate vaccine (PCV) in human immunodeficiency virus (HIV) and non-HIV-infected children under two years of age. Sixteen HIV-infected and 14 non-HIV-infected children under two years of age, and of similar age, race and sex distribution, received three doses (separated by two months each) of a five-valent oligosaccharide PCV (types 6B, 14, 18C, 19F, and 23F separately coupled to diphtheria CRM197). An additional 11 non-HIV-infected children, of similar demographic distribution to the PCV groups, received three doses of saline placebo. sera were collected just prior to, and at one and eight months after the three study drug doses. Serum vaccine type-specific pneumococcal IgG antibodies were measured by enzyme-linked immunoabsorbant assay (ELISA). There was an impressive rise in antibody titers pre- to one month post-third PCV in both the HIV (58-970-fold) and non-HIV-infected (19-553-fold) children. There was a rapid and similar drop in antibody titers eight months after the PCV series for both HIV (range 69-87% drop) and non-HIV-infected (range 57-79% drop) subjects respectively. However, 46% of the antibody titers from HIV-infected children and 62% of the titers from non-HIV-infected children were still > 1.0 microgram ml-1 compared to placebo recipients for whom only 5% of the titers were > 1.0 microgram ml-1 (p < 0.05). At the eight month post-PCV series blood draw, there were no significant differences in the GMTs, the percent drop in titers, or proportion of titers > 1.0 microgram ml-1 between the five HIV-infected children who had advanced (CDC class: N3, A3, B2-3, C1-3) compared to the 11 children with mild (CDC class: N1-2, A1-2, B1) HIV disease at the time of their first PCV dose. Eight months after the PCV series, the proportion of titers (combined all five serotypes) > 1.0 microgram ml-1 was slightly, but significantly, lower for HIV-infected subjects (46%) compared to non-HIV-infected subjects (62%) (p < 0.05). These data are helpful in describing the kinetics of antibody responses to pneumococcal conjugate vaccines in both HIV and non-HIV-infected young children.
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Shafran SD, Sacks SL, Aoki FY, Tyrrell DL, Schlech WF, Mendelson J, Rosenthal D, Gill MJ, Bader RL, Chang I. Topical undecylenic acid for herpes simplex labialis: a multicenter, placebo-controlled trial. J Infect Dis 1997; 176:78-83. [PMID: 9207352 DOI: 10.1086/514042] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A multicenter, patient-initiated, double-blind, placebo-controlled trial of 15% undecylenic acid cream was conducted with 573 patients with recurrent herpes labialis. Treatment was applied 5 or 6 times daily until crusting and then thrice daily until healing. Patients were assessed daily until 48 h after crusting and then every other day until healing. Undecylenic acid significantly reduced the incidence and duration of viral shedding and the duration and severity of itching but did not increase abortive episodes or reduce times to healing, crusting, or progression of lesion size. When treatment was initiated during the prodrome, the time to crusting was reduced (P = .02) and the area under the symptom-time curve for pain and tenderness was reduced, approaching statistical significance (P = .06). Active treatment was well tolerated but caused dysgeusia and local irritation. Undecylenic acid 15% cream reduces viral shedding in recurrent herpes labialis, but clinical benefits are minimal and largely restricted to patients initiating therapy during the prodrome.
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Thomas CE, Mayer SA, Gungor Y, Swarup R, Webster EA, Chang I, Brannagan TH, Fink ME, Rowland LP. Myasthenic crisis: clinical features, mortality, complications, and risk factors for prolonged intubation. Neurology 1997; 48:1253-60. [PMID: 9153452 DOI: 10.1212/wnl.48.5.1253] [Citation(s) in RCA: 209] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We retrospectively reviewed the hospital records of 53 patients admitted for 73 episodes of myasthenic crisis at Columbia-Presbyterian Medical Center over a period of 12 years, from 1983 to 1994. Median age at the onset of first crisis was 55 (range, 20 to 82), the ratio of women to men was 2:1, and the median interval from onset of symptoms to first crisis was 8 months. Infection (usually pneumonia or upper respiratory infection) was the most common precipitating factor (38%), followed by no obvious cause (30%) and aspiration (10%). Twenty-five percent of patients were extubated at 7 days, 50% at 13 days, and 75% at 31 days; the longest crisis exceeded 5 months. Using survival analysis and backward stepwise Cox regression, we identified three independent predictors of prolonged intubation: (1) pre-intubation serum bicarbonate > or = 30 mg/dl (p = 0.0004, relative hazard 4.5), (2) peak vital capacity day 1 to 6 post-intubation < 25 ml/kg (p = 0.001, relative hazard 2.9), and (3) age > 50 (p = 0.01, relative hazard 2.4). The proportion of patients intubated longer than 2 weeks was 0% among those with no risk factors, 21% with one risk factor, 46% with two risk factors, and 88% with three risk factors (p = 0.0004). Complications independently associated with prolonged intubation included atelectasis (p = 0.002), anemia treated with transfusion (p = 0.03), Clostridium difficile infection (p = 0.01), and congestive heart failure (p = 0.03). Three episodes of crisis were fatal, for a mortality rate of 4% (3/73); four additional patients died after extubation. All seven deaths were due to overwhelming medical comorbidity. Over half of those who survived were functionally dependent (home or institutionalized) at discharge. In addition to prospective controlled studies of immunotherapies, the prevention and treatment of medical complications offers the best opportunity for further improving the outcome of myasthenic crisis.
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Tracey I, Lane J, Chang I, Navia B, Lackner A, González RG. 1H magnetic resonance spectroscopy reveals neuronal injury in a simian immunodeficiency virus macaque model. JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES AND HUMAN RETROVIROLOGY : OFFICIAL PUBLICATION OF THE INTERNATIONAL RETROVIROLOGY ASSOCIATION 1997; 15:21-7. [PMID: 9215650 DOI: 10.1097/00042560-199705010-00004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Infection with human immunodeficiency virus (HIV) commonly results in neurologic disease called the AIDS dementia complex. Neuronal loss and injury have been found in the HIV brain, but the underlying mechanisms are not understood. The simian immunodeficiency virus (SIV)-infected macaque is an excellent animal model for HIV infection, but neuronal loss has not been demonstrated. To determine whether neuronal damage occurs in the SIV brain, we quantified the neuronal marker N-acetylaspartate (NAA) using proton magnetic resonance spectroscopy (1H-MRS) in brain extracts of control and SIV-infected macaques and correlated these findings with histologic analyses. We found reduced NAA in the SIV-infected animals compared with controls (2.94 +/- 1.37 versus 6.21 +/- 1.73 micromol/g of wet weight; p = 0.004). A significant decrease in NAA was also found in SIV-infected animals sacrificed in the acute stages of infection 9 or 10 days after inoculation with SIVmacYnef. We conclude that SIV infection of rhesus macaques results in neuronal damage that is demonstrable shortly after infection and that 1H-MRS may be used to measure such injury. The results further support the SIV macaque as a useful model to study the mechanisms of neuropathogenesis by HIV.
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