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Stewart JA, Hamilton PJ, Murdoch AP. Thromboembolic disease associated with ovarian stimulation and assisted conception techniques. Hum Reprod 1997; 12:2167-73. [PMID: 9402276 DOI: 10.1093/humrep/12.10.2167] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Thromboembolic disease, as a complication of ovarian stimulation and assisted conception techniques, is generally considered to be a rare complication of ovarian hyperstimulation syndrome and, by implication, lower limb in origin. Sporadic cases of unusually sited thromboses, both venous and arterial, have been reported. This paper aims to draw attention to the relatively large number of such thromboses reported in the world literature compared with those cited in previous commentaries, and to emphasize how little is known about their pathogenesis. It is believed that this is an issue which requires to be addressed in order to understand the background pathology to such incidents and if possible to identify women at greatest risk from such potentially debilitating or fatal complications, such that appropriate prophylactic measures can be taken.
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Solomon KD, Turkalj JW, Whiteside SB, Stewart JA, Apple DJ. Topical 0.5% ketorolac vs 0.03% flurbiprofen for inhibition of miosis during cataract surgery. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 1997; 115:1119-22. [PMID: 9298051 DOI: 10.1001/archopht.1997.01100160289004] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
OBJECTIVE To compare the effects of topical 0.5% ketorolac tromethamine ophthalmic solution (Acular, Allergen Pharmaceuticals, Irvine, Calif) with topical 0.03% flurbiprofen sodium ophthalmic solution (Ocufen, Allergen Pharmaceuticals) on the inhibition of surgically induced miosis during phacoemulsification cataract surgery. DESIGN One hundred eighteen patients were prospectively randomized to receive 0.5% topical ketorolac or 0.03% topical flurbiprofen at 3 preoperative intervals. The flurbiprofen-treated group served as the control group. The surgeon was masked as to patient selection. Horizontal pupillary diameter measurements were obtained at the start of surgery, just before phacoemulsification, before lens implantation, and after lens implantation. RESULTS Mean horizontal pupillary diameter measurements for both medications were similar at the start of surgery. However, a consistent trend of larger pupillary diameter was seen in all subsequent surgical intervals in the ketorolac-treated group. Changes from baseline measurements also indicated a more significant inhibition of miosis at all subsequent intervals, and a more stable mydriasis throughout the procedure in the ketorolac-treated group. CONCLUSIONS Topical ketorolac is an effective inhibitor of miosis during phacoemulsification cataract surgery, and provides a more stable mydriatic effect throughout the surgical procedure.
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Reyes M, Gary HE, Dobbins JG, Randall B, Steele L, Fukuda K, Holmes GP, Connell DG, Mawle AC, Schmid DS, Stewart JA, Schonberger LB, Gunn WJ, Reeves WC. Surveillance for chronic fatigue syndrome--four U.S. cities, September 1989 through August 1993. MMWR. CDC SURVEILLANCE SUMMARIES : MORBIDITY AND MORTALITY WEEKLY REPORT. CDC SURVEILLANCE SUMMARIES 1997; 46:1-13. [PMID: 12412768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
PROBLEM/CONDITION Although chronic fatigue syndrome (CFS) has been recognized as a cause of morbidity in the United States, the etiology of CFS is unknown. In addition, information is incomplete concerning the clinical spectrum and prevalence of CFS in the United States. REPORTING PERIOD COVERED This report summarizes CFS surveillance data collected in four U.S. cities from September 1989 through August 1993. DESCRIPTION OF SYSTEM A physician-based surveillance system for CFS was established in four U.S. metropolitan areas: Atlanta, Georgia; Wichita, Kansas; Grand Rapids, Michigan; and Reno, Nevada. The objectives of this surveillance system were to collect descriptive epidemiologic information from patients who had unexplained chronic fatigue, estimate the prevalence and incidence of CFS in defined populations, and describe the clinical course of CFS. Patients aged > or = 18 years who had had unexplained, debilitating fatigue or chronic unwellness for at least 6 months were referred by their physicians to a designated health professional(s) in their area. Those patients who participated in the surveillance system a) were interviewed by the health professional(s); b) completed a self-administered questionnaire that included their demographic information, medical history, and responses to the Beck Depression Inventory, the Diagnostic Interview Schedule, and the Sickness Impact Profile; c) submitted blood and urine samples for laboratory testing; and d) agreed to a review of their medical records. On the basis of this information, patients were assigned to one of four groups: those whose illnesses met the criteria of the 1988 CFS case definition (Group I); those whose fatigue or symptoms did not meet the criteria for CFS (Group II); those who had had an identifiable psychological disorder before onset of fatigue (Group III); and those who had evidence of other medical conditions that could have caused fatigue (Group IV). Patients assigned to Group III were further evaluated to determine the group to which they would have been assigned had psychological illness not been present, the epidemiologic characteristics of the illness and the frequency of symptoms among patients were evaluated, and the prevalence and incidence of CFS were estimated for each of the areas. RESULTS Of the 648 patients referred to the CFS surveillance system, 565 (87%) agreed to participate. Of these, 130 (23%) were assigned to Group I; 99 (18%), Group II; 235 (42%), Group III; and 101 (18%), Group IV. Of the 130 CFS patients, 125 (96%) were white and 111 (85%) were women. The mean age of CFS patients at the onset of illness was 30 years, and the mean duration of illness at the time of the interview was 6.7 years. Most (96%) CFS patients had completed high school, and 38% had graduated from college. The median annual household income/for CFS patients was $40,000. In the four cities, the age-, sex-, and race-adjusted prevalences of CFS for the 4-year surveillance period ranged from 4.0 to 8.7 per 100,000 population. The age-adjusted 4-year prevalences of CFS among white women ranged from 8.8 to 19.5 per 100,000 population. INTERPRETATION The results of this surveillance system were similar to those in previously published reports of CFS. Additional studies should be directed toward determining whether the data collected in this surveillance system were subject to selection bias (e.g., education and income levels might have influenced usage of the health-care system, and the populations of these four surveillance sites might not be representative of the U.S. population). ACTIONS TAKEN In February 1997, CDC began a large-scale, cross-sectional study at one surveillance site (Wichita) to describe more completely the magnitude and epidemiology of unexplained chronic fatigue and CFS.
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Stroman GA, Stewart WC, Stewart JA, Deitz TM. Safety of beta-adrenergic blocker washout period in clinical trials. ACTA OPHTHALMOLOGICA SCANDINAVICA 1997; 75:94-5. [PMID: 9088411 DOI: 10.1111/j.1600-0420.1997.tb00259.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We prospectively evaluated the safety of the washout period from topical beta-adrenergic blockers prior to clinical drug trials. In 30 consecutive patients optic disc parameters (neural rim, optic disc, peripapillary halo and atrophy areas, and venous/arterial diameters) did not change following washout (p > 0.05). Likewise, the mean defect and pattern standard deviation (Humphrey 30-2) did not change following washout (p > 0.05). This study suggests, generally, the safety of the washout period prior to clinical drug trials.
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Carbone PP, Bailey HH, Stewart JA. Breast cancer. CANCER CHEMOTHERAPY AND BIOLOGICAL RESPONSE MODIFIERS 1997; 17:562-611. [PMID: 9551231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Mawle AC, Nisenbaum R, Dobbins JG, Gary HE, Stewart JA, Reyes M, Steele L, Schmid DS, Reeves WC. Immune responses associated with chronic fatigue syndrome: a case-control study. J Infect Dis 1997; 175:136-41. [PMID: 8985207 DOI: 10.1093/infdis/175.1.136] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
An exploratory case-control study was conducted to assess whether the many reported differences in the immune function of chronic fatigue syndrome (CFS) patients are detectable in rigorously defined cases of CFS. Although many studies have reported differences between cases and controls in various measures of immune function, none of these differences were found in all studies. In this study, no differences were found in white blood cell numbers; immune complex, complement, or serum immunoglobulin levels; delayed type hypersensitivity and allergic responses; NK cell function; and proliferative responses to mitogens and antigens. Marginal differences were detected in cytokine responses and in cell surface markers in the total CFS population. However, when the patients were subgrouped by type of disease onset (gradual or sudden) or by how well they were feeling on the day of testing, more pronounced differences were seen.
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Robins HI, Rushing D, Kutz M, Tutsch KD, Tiggelaar CL, Paul D, Spriggs D, Kraemer C, Gillis W, Feierabend C, Arzoomanian RZ, Longo W, Alberti D, d'Oleire F, Qu RP, Wilding G, Stewart JA. Phase I clinical trial of melphalan and 41.8 degrees C whole-body hyperthermia in cancer patients. J Clin Oncol 1997; 15:158-64. [PMID: 8996137 DOI: 10.1200/jco.1997.15.1.158] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
PURPOSE To evaluate the biologic interactions and toxicities of melphalan (L-PAM) combined with 41.8 degrees C whole-body hyperthermia (WBH) for 60 minutes. PATIENTS AND METHODS Sixteen patients with refractory cancer were treated (May 1992 to May 1995) with WBH alone during week 1) thereafter patients were randomized to receive either L-PAM alone on week 2 and L-PAM plus WBH on week 5, or the reverse sequence. Patients who demonstrated clinical improvement received WBH plus L-PAM monthly. Dose levels of L-PAM were 10 mg/m2 (n = 3), 15 mg/m2 (n = 3), 17.5 mg/m2 (n = 6), and 20 mg/m2 (n = 4). L-PAM was administered at target temperature; WBH was administered with an Aquatherm radiant-heat device (patent pending; Cancer Research Institute, New York, NY). RESULTS Comparisons of mean WBC count and platelet nadirs for L-PAM alone and L-PAM plus WBH demonstrated that the addition of WBH resulted in nadir counts that were, on average, 25% lower. There were no instances of febrile neutropenia or bleeding. Toxicities allowed for escalation of L-PAM to 20 mg/m2; all four patients at this level experienced grade 4 myelosuppression. No significant myelosuppression was observed at 10 and 15 mg/m2. Grade 3 myelosuppression was observed in two of six patients at 17.5 mg/m2. Responses included complete remission (CR) of pancreatic cancer (10 mg/m2), partial remission (PR) of malignant melanoma in two patients (20 mg/m2), and transient clinical and/or serologic improvement in five patients. The pharmacokinetics of L-PAM were not altered by WBH. Observed cytokine induction by WBH is also discussed in detail. CONCLUSION We conclude that L-PAM with 41.8 degrees C WBH is well tolerated. Clinical results are consistent with preclinical predictions and provide a foundation for second-generation trials now in progress.
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Stewart JA, Rathbone BJ. Nurse endoscopists and percutaneous endoscopic gastrostomy (PEG) insertion. Eur J Gastroenterol Hepatol 1997; 9:93. [PMID: 9031908 DOI: 10.1097/00042737-199701000-00022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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85
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Stewart WC, Sine C, Sutherland S, Stewart JA. Total cholesterol and high-density lipoprotein levels as risk factors for increased intraocular pressure. Am J Ophthalmol 1996; 122:575-7. [PMID: 8862057 DOI: 10.1016/s0002-9394(14)72121-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
PURPOSE To determine whether high-density lipoprotein and total cholesterol levels were risk factors for increased intraocular pressure in patients with chronic open-angle glaucoma or ocular hypertension. METHODS We measured total cholesterol, high-density lipoprotein, and total cholesterol/high-density lipoprotein ratio in 25 patients with open-angle glaucoma or ocular hypertension who had taken no glaucoma medications for four weeks. We individually matched these patients to 25 control subjects who had no history of open-angle glaucoma or ocular hypertension, on the basis of age, race, gender, and history of vascular disease or diabetes mellitus. RESULTS We found no statistical difference in the high-density lipoprotein (P = .702) or total cholesterol (P = .177) levels or total cholesterol/high-density lipoprotein ratio between groups (P = .178, paired t test). CONCLUSION This study indicates that increased high-density lipoprotein and total cholesterol levels are not risk factors for increased intraocular pressure.
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Simonsen L, Khan AS, Gary HE, Hanson C, Pallansch MA, Music S, Holman RC, Stewart JA, Erdman DD, Arden NH, Arenberg IK, Schonberger LB. Outbreak of vertigo in Wyoming: possible role of an enterovirus infection. Epidemiol Infect 1996; 117:149-57. [PMID: 8760963 PMCID: PMC2271687 DOI: 10.1017/s0950268800001254] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
An epidemiologic investigation was conducted to characterize and evaluate the possibility of a viral aetiology of an outbreak of acute vertigo in Hot Springs Country, Wyoming, during autumn 1992. Case-finding identified Hot Springs County residents who sought medical attention for new onset vertigo during 1 August, 1992-31 January 1993. Thirty-five case-patients and 61 matched controls were interviewed and serum specimens were obtained during January 1993. Case-patients were more likely than controls to report symptoms (e.g. fatigue, sore throat, fever, diarrhoea) of antecedent acute illness. Case-patients did not have a significantly greater prevalence or mean titre of IgG antibodies to respiratory syncytial virus, parainfluenza viruses, Epstein-Barr virus, and cytomegalovirus than controls. Serologic evidence of recent enterovirus infection (IgM antibodies) was found for 74% of case-patients compared with 54% of controls (P < 0.05), suggesting a possible association between vertigo and enterovirus infection. Future studies are needed to define the role of enteroviruses in innerear diseases.
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Abstract
Survival rates from in-hospital cardiac arrests are low and have not improved since the 1960s. Increased emphasis on early defibrillation has significantly improved prehospital survival rates in recent years, but the organization of resuscitation efforts in hospitals has not changed. Nurses throughout the hospital should be trained and authorized to defibrillate on their own initiative, using defibrillators that are already close at hand. The basic procedure is not difficult, and an aggressive protocol using blind defibrillation could further simplify training and maximize survival. Working together, nurses can overcome psychologic and emotional barriers to these changes and improve their patients' odds of survival.
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Jackson LA, Stewart LK, Solomon SL, Boase J, Alexander ER, Heath JL, McQuillan GK, Coleman PJ, Stewart JA, Shapiro CN. Risk of infection with hepatitis A, B or C, cytomegalovirus, varicella or measles among child care providers. Pediatr Infect Dis J 1996; 15:584-9. [PMID: 8823851 DOI: 10.1097/00006454-199607000-00005] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
BACKGROUND Employment as a child care provider has been suggested as an indication for hepatitis A virus (HAV) immunization; however, whether this occupational group is at increased risk of HAV infection is not well-defined. METHODS We obtained sera samples for testing for antibodies to hepatitis A, B and C, cytomegalovirus, varicella and measles from a sample of child care providers in King County, WA, and administered a questionnaire to assess employment characteristics and other potential risk factors for infection. We also compared the anti-HAV seroprevalence among providers with that of subjects in the Third National Health and Nutrition Survey, representative of the US general population. RESULTS Thirteen percent (48 of 360) of providers were anti-HAV-positive (46% (22 of 47) of foreign born vs. 8% (26 of 313) of US-born (P < 0.001)). In multivariate analysis anti-HAV seropositivity was associated with foreign birth, age, income and Hispanic ethnicity but was not associated with characteristics of employment. Seroprevalence among US-born providers tended to be lower than that among Third National Health and Nutrition Survey subjects of similar age, sex, race and income. Sixty-two percent of providers were seropositive to cytomegalovirus, which was associated with nonwhite race, changing diapers > or = 3 days/week while at work and having a child in the household. Antibody prevalence was 1.4% to hepatitis B core antigen, 0.6% to hepatitis C, 94% to measles and 98% to varicella. CONCLUSIONS The anti-HAV prevalence among US-born providers was low, and seropositivity was not associated with employment characteristics, indicating that occupational exposure to HAV is uncommon under non-outbreak circumstances.
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Kadakia MP, Rybka WB, Stewart JA, Patton JL, Stamey FR, Elsawy M, Pellett PE, Armstrong JA. Human herpesvirus 6: infection and disease following autologous and allogeneic bone marrow transplantation. Blood 1996; 87:5341-54. [PMID: 8652850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Human herpesvirus 6 activity (HHV-6) was studied in 15 allogeneic and 11 autologous marrow transplantation patients. After transplantation, HHV-6 was isolated from the peripheral blood mononuclear cells of 12 of 26 patients (6 allogeneic and 6 autologous). All isolates were variant B. Eleven of 26 and 12 of 19 patients showed salivary shedding of HHV-6 DNA before and after transplantation, respectively. The antibody titer increased in 7 of 26 patients. Thus, 23 of 26 patients showed evidence of active HHV-6 infection either by virus isolation, salivary shedding, or increases in antibody titers. The fraction of saliva specimens positive in 19 patients was negatively associated with their antibody titers (P= .005). The proportion of cultures positive increased after transplantation (P = .007). Sinusitis was associated with HHV-6 isolation in autologous recipients (P= .002). In allogeneic patients, active human cytomegalovirus infection was associated with HHV-6 isolation (P = .04). No association was observed between HHV-6 infection and GVHD, pneumonia, delay in engraftment, or marrow suppression. Of the 120 clinical events analyzed in 26 patients, HHV-6 was defined as a probable cause of 16 events in 9 patients based on the propinquity of HHV-6 activity and the clinical event plus the absence of other identified causes of the event.
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Einzig AI, Neuberg D, Remick SC, Karp DD, O'Dwyer PJ, Stewart JA, Benson AB. Phase II trial of docetaxel (Taxotere) in patients with adenocarcinoma of the upper gastrointestinal tract previously untreated with cytotoxic chemotherapy: the Eastern Cooperative Oncology Group (ECOG) results of protocol E1293. Med Oncol 1996; 13:87-93. [PMID: 9013471 DOI: 10.1007/bf02993858] [Citation(s) in RCA: 151] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The aim of this study was to evaluate the clinical efficacy and safety of docetaxel (Taxotere) in patients with adenocarcinoma of the upper gastrointestinal tract previously untreated with cytotoxic chemotherapy. Docetaxel 100 mg m-2 was administered as a 1 hour intravenous (IV) infusion every 3 weeks to 41 patients. Patients were premedicated prior to each course with dexamethasone, diphenhydramine and cimetidine. Clinical response and toxicity were determined. Objective responses were seen in seven of 41 eligible patients (two complete responses [CRs] and five partial responses [PRs], for an objective response rate of 17% (90% confidence interval [CI], 8% to 30%). The most common toxicity was grade 4 neutropenia, which occurred in 88% of patients; 46% of patients required a dose reduction following an episode of neutropenic fever requiring antibiotic therapy. Additional patients have had reversible grade 3-4 toxicities including nausea, vomiting, stomatitis, diarrhea, fatigue and peripheral neuropathy. Ten patients have had grade 1-3 hypersensitivity reactions. Alopecia has been seen in the majority of patients. Fluid retention grade 1-3 has been observed in patients. Docetaxel administered on this schedule is an active agent in adenocarcinomas of the upper gastrointestinal tract. Further investigation of this drug should be conducted in multi-drug combination programs.
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Morton PA, Fu XT, Stewart JA, Giacoletto KS, White SL, Leysath CE, Evans RJ, Shieh JJ, Karr RW. Differential effects of CTLA-4 substitutions on the binding of human CD80 (B7-1) and CD86 (B7-2). THE JOURNAL OF IMMUNOLOGY 1996. [DOI: 10.4049/jimmunol.156.3.1047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
CTLA-4 expressed on activated T cells binds to CD80 (B7-1) and CD86 (B7-2) molecules present on APC with high avidity and appears to deliver a negative regulatory signal to the T cell. We have investigated the kinetics of CTLA-4 binding to CD80 and CD86, together with the effects of selected CTLA-4 mutations on binding activity. The dissociation constants (Kd) for binding of CTLA-4-Ig to CD80 and CD86 transfectants were 8.1 and 6.7 nM, respectively. Surface plasmon resonance was used to determine kinetic parameters of CTLA-4-Ig binding to CD80-Ig and CD86-Ig fusion proteins and revealed enhanced association (ka) and dissociation (kd) rate constants for CD86-Ig compared with CD80-Ig. Furthermore, CD80-Ig and CD86-Ig fusion molecules demonstrated variable abilities to cross-compete for binding to several modified forms of CTLA-4-Ig. Differential binding of CD80 and CD86 to CTLA-4 was further revealed by analysis of 10 discrete CTLA-4 mutants. Five single amino acid substitutions within the CTLA-4 MYPPPY domain exerted modest effects on CD80 binding, but each of these substitutions completely abrogated CD86 binding. In addition, substitutions just N-terminal of the MYPPPY region, and within the CDR1-like region of CTLA-4, eliminated both CD80 and CD86 binding. Hence, CD80 and CD86 bind with different association/dissociation kinetics to similar, but distinct, sites on CTLA-4.
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Morton PA, Fu XT, Stewart JA, Giacoletto KS, White SL, Leysath CE, Evans RJ, Shieh JJ, Karr RW. Differential effects of CTLA-4 substitutions on the binding of human CD80 (B7-1) and CD86 (B7-2). JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1996; 156:1047-54. [PMID: 8557978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
CTLA-4 expressed on activated T cells binds to CD80 (B7-1) and CD86 (B7-2) molecules present on APC with high avidity and appears to deliver a negative regulatory signal to the T cell. We have investigated the kinetics of CTLA-4 binding to CD80 and CD86, together with the effects of selected CTLA-4 mutations on binding activity. The dissociation constants (Kd) for binding of CTLA-4-Ig to CD80 and CD86 transfectants were 8.1 and 6.7 nM, respectively. Surface plasmon resonance was used to determine kinetic parameters of CTLA-4-Ig binding to CD80-Ig and CD86-Ig fusion proteins and revealed enhanced association (ka) and dissociation (kd) rate constants for CD86-Ig compared with CD80-Ig. Furthermore, CD80-Ig and CD86-Ig fusion molecules demonstrated variable abilities to cross-compete for binding to several modified forms of CTLA-4-Ig. Differential binding of CD80 and CD86 to CTLA-4 was further revealed by analysis of 10 discrete CTLA-4 mutants. Five single amino acid substitutions within the CTLA-4 MYPPPY domain exerted modest effects on CD80 binding, but each of these substitutions completely abrogated CD86 binding. In addition, substitutions just N-terminal of the MYPPPY region, and within the CDR1-like region of CTLA-4, eliminated both CD80 and CD86 binding. Hence, CD80 and CD86 bind with different association/dissociation kinetics to similar, but distinct, sites on CTLA-4.
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Stewart JA. Delayed in-hospital defibrillation. Ann Emerg Med 1996; 27:104-5. [PMID: 8572440 DOI: 10.1016/s0196-0644(96)70310-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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Black JB, Schwarz TF, Patton JL, Kite-Powell K, Pellett PE, Wiersbitzky S, Bruns R, Müller C, Jäger G, Stewart JA. Evaluation of immunoassays for detection of antibodies to human herpesvirus 7. CLINICAL AND DIAGNOSTIC LABORATORY IMMUNOLOGY 1996; 3:79-83. [PMID: 8770508 PMCID: PMC170251 DOI: 10.1128/cdli.3.1.79-83.1996] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
An enzyme immunoassay (EIA), an immunoblot assay (IB), and an indirect immunofluorescence assay were developed for detection of human herpesvirus 7 (HHV-7) antibodies in human serum. Cross-absorption studies with EIA or IFA using HHV-7 and human herpesvirus 6 (HHV-6) antigens indicated that most human sera contain cross-reactive HHV-6 and HHV-7 antibodies and that the degree of cross-reactivity varies between individual serum specimens. Inhibition of homologous antibody activity by absorption with heterologous virus ranged from 0 to 57% by EIA. However, for every sample tested, absorption with homologous virus removed more activity than did heterologous virus. An 89-kDa protein was identified as an HHV-7-specific serologic marker by IB. Activity to this protein was not removed by absorption with HHV-6 antigen. Of the three assays, the EIA was the most sensitive (94%), while the IB was the most specific (94%). Approximately 80% of specimens collected from German adults and children older than 2 years were positive for HHV-7 antibodies by these assays.
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Lin JC, Lin SC, Mar EC, Pellett PE, Stamey FR, Stewart JA, Spira TJ. Is Kaposi's-sarcoma-associated herpesvirus detectable in semen of HIV-infected homosexual men? Lancet 1995; 346:1601-2. [PMID: 7500753 DOI: 10.1016/s0140-6736(95)91931-7] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
We explored a possible route of transmission of Kaposi's-sarcoma-associated herpes virus (KSHV) with nested and unnested PCR techniques. We looked for KSHV DNA sequences in semen of HIV-positive homosexual men and HIV-negative healthy semen donors. With unnested primers we found KSHV sequences in 21 of 33 (64%) homosexual men and in none of 30 healthy donors. With a nested PCR assay, 30 of 33 (91%) specimens from the homosexual men and 7 of 30 (23%) specimens from healthy donors had detectable KSHV sequences. Over 5 years of follow-up, 13 of 30 KSHV-positive homosexual men (43%) developed KS compared with none of the 3 KSHV-negative homosexual men.
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Mawle AC, Nisenbaum R, Dobbins JG, Gary HE, Stewart JA, Reyes M, Steele L, Schmid DS, Reeves WC. Seroepidemiology of chronic fatigue syndrome: a case-control study. Clin Infect Dis 1995; 21:1386-9. [PMID: 8749620 PMCID: PMC7197952 DOI: 10.1093/clinids/21.6.1386] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
We performed serological testing for a large number of infectious agents in 26 patients from Atlanta who had chronic fatigue syndrome (CFS) and in 50 controls matched by age, race, and sex. We did not find any agent associated with CFS. In addition, we did not find elevated levels of antibody to any of a wide range of agents examined. In particular, we did not find elevated titers of antibody to any herpesvirus, nor did we find evidence of enteroviral exposure in this group of patients.
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Clarke T, Evans ME, Hepworth G, Moate PJ, Stewart JA. Mordant factors that affect the fluorescence and counting of somatic cells by instruments. J DAIRY RES 1995; 62:373-94. [PMID: 7593825 DOI: 10.1017/s0022029900031095] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The requirement for accuracy in the counting of somatic cells in milk has been increased by the use of this measurement as a basis of payment for milk. This paper reports on several factors that can substantially affect efficiency of staining and cell detection in various types of fluorescent cell counters. These mordant factors include sample age, chemical preservative, other sample preservation treatments and reagent properties. Experiments were conducted in several laboratories with Fossomatic 215 and 360 cell counting instruments to measure the effect of these mordant factors on both cell fluorescence and cell count. Counting efficiency was as low as 20% for some instruments counting some particular samples, depending upon the combination of adverse mordant factors. The problem of poor counting efficiency was also not detected by calibration samples that had more favourable mordant treatments applied. The adverse mordant factors were shown to reduce the intensity of fluorescence of cells for all instruments. We suggest that a significant reduction in counting efficiency due to these adverse mordant factors is most likely to occur when the particular instrument already has an intrinsic inability to separate cell fluorescence properly from background noise. This paper also discusses quality control samples, the impact of various factors on discriminator curves and the use of appropriate measures to maintain good calibration adjustment.
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99
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Stewart JA, Reef SE, Pellett PE, Corey L, Whitley RJ. Herpesvirus infections in persons infected with human immunodeficiency virus. Clin Infect Dis 1995; 21 Suppl 1:S114-20. [PMID: 8547499 DOI: 10.1093/clinids/21.supplement_1.s114] [Citation(s) in RCA: 80] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Herpesviruses are among the most common causes of infections of humans. Viruses in this family share the unique biological property of being able to establish latency and to recur. Furthermore, chronic excretion of virus is not uncommon. In the immunocompromised host, including persons with human immunodeficiency virus (HIV) infection, herpesvirus disease can be particularly severe, resulting in chronic, persistent, active infection and, in some cases, life-threatening disease. The most pathogenic of the herpesviruses in patients with AIDS include herpes simplex viruses, human cytomegalovirus, and varicella-zoster virus. Disease caused by Epstein-Barr virus, particularly opportunistic malignancies, has been recognized. A new herpesvirus that is associated with Kaposi's sarcoma was recently described. On the other hand, disease caused by human herpesviruses 6 and 7 in persons infected with HIV remains to be unequivocally recognized. Prevention of exposure to herpesviruses, disease, and recurrence requires different measures than those for some of the other opportunistic infections in HIV-infected patients; this is because herpesvirus disease develops in most of these individuals as a result of reactivation rather than primary infection. Thus, approaches to the prevention and control of herpesvirus infections must be individualized according to both the type of virus as well as the type of infection (i.e., primary or recurrent). We discuss recommended measures for the prevention and control of these infections.
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100
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Sramek JJ, Viereck C, Huff FJ, Wardle T, Hourani J, Stewart JA, Cutler NR. A "bridging" (safety/tolerance) study of besipirdine hydrochloride in patients with Alzheimer's disease. Life Sci 1995; 57:1241-8. [PMID: 7674813 DOI: 10.1016/0024-3205(95)02068-t] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Besipirdine hydrochloride is a novel compound with cholinergic and adrenergic activity being investigated as a treatment for Alzheimer's disease (AD). The pharmacodynamics of some anti-dementia drugs are known to differ in patients with AD as compared with elderly normals. The present study was designed to determine the maximum tolerated dose (MTD) of multiple oral doses of besipirdine in AD patients. Twelve AD patients (NINCDS/ADRDA criteria; 7M, 5F, ages 58-75, mean age 65) were randomized to besipirdine (n = 9) or placebo (n = 3) in a double-blind, parallel-group, rising-dose design. Doses were 10, 20, 30, and 40 mg bid for 2 days each, followed by 50 and 60 mg bid for 5 days each. The most common adverse events were asymptomatic postural hypotension and asymptomatic bradycardia. Two patients on active drug developed severe adverse events: 1 after 3 days at 50 mg bid (nausea and vomiting); 1 after 3 days at 60 mg bid (angina). Due to the anginal episode, the study was terminated on Day 17. Plasma concentrations increased linearly with dose for besipirdine and its major metabolite. The two patients who developed severe adverse events had the highest plasma concentrations measured. Besipirdine 50 mg bid was considered the maximum tolerated dose (MTD).
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