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Pellino T, Tluczek A, Collins M, Trimborn S, Norwick H, Engelke ZK, Broad J. Increasing self-efficacy through empowerment: preoperative education for orthopaedic patients. Orthop Nurs 1998; 17:48-51, 54-9. [PMID: 9814337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
PURPOSE To examine whether patients who received an empowerment model of education for preoperative orthopaedic teaching had improved outcomes compared to patients who received the traditional education. DESIGN An experimental (empowerment teaching method) group vs. comparison (traditional teaching method) group posttest design. SAMPLE Seventy-four patients undergoing elective orthopaedic surgery. METHODS Following the preoperative teaching session, patients in both groups completed a questionnaire designed to measure their perceptions of the teaching (empowerment) and self-efficacy (belief in their ability to carry out perioperative tasks). A chart audit and phone interview was done after discharge to assess length of stay, pain management, complications, and patient perceptions of the ability to complete perioperative tasks. FINDINGS Patients in the empowerment group felt the educational approach was more empowering and had significantly higher self-efficacy scores than those in the traditional teaching group. There was much less variation in empowerment and self-efficacy scores in the empowerment group. The empowerment group reported feeling greater confidence in performing perioperative tasks. There were no differences in length of stay, complications or pain control. CONCLUSION Use of an empowerment teaching approach enabled patients to become more confident in their ability to carry out perioperative tasks and become a more integral part of the preoperative teaching process. IMPLICATIONS FOR NURSING RESEARCH The theoretical model will be used to structure other educational programs and guide research. More sensitive measures of complications and pain control should be considered for future studies.
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Morales A, Gingell C, Collins M, Wicker PA, Osterloh IH. Clinical safety of oral sildenafil citrate (VIAGRA) in the treatment of erectile dysfunction. Int J Impot Res 1998; 10:69-73; discussion 73-4. [PMID: 9647940 DOI: 10.1038/sj.ijir.3900354] [Citation(s) in RCA: 340] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Sildenafil citrate has been shown to be effective in a wide range of patients with erectile dysfunction and has been approved in the United States for this indication. The overall clinical safety of oral sildenafil, a potent inhibitor of phosphodiesterase type 5, in the treatment of erectile dysfunction was evaluated in more than 3700 patients (with a total of 1631 years of exposure worldwide). Safety and tolerability data were analysed from a series of double-blind, placebo-controlled studies and from 10 open-label extension studies of sildenafil in the treatment of erectile dysfunction. A total of 4274 patients (2722 sildenafil, 1552 placebo; age range 19-87 y) received double-blind treatment over a period of up to six months' duration, and 2199 received long-term, open-label sildenafil for up to 1 y. The most commonly reported adverse events (all causes) were headache (16% sildenafil, 4% placebo), flushing (10% sildenafil, 1% placebo), and dyspepsia (7% sildenafil, 2% placebo) and they were predominantly transient and mild or moderate in nature. These adverse events reflect the pharmacology of sildenafil as a phosphodiesterase type 5 inhibitor. No cases of priapism were reported. The rate of discontinuation due to adverse events (all causes) was comparable for patients treated with sildenafil (2.5%) and placebo (2.3%). In open-label extension studies, 90% of patients completed long-term sildenafil treatment, with only 2% withdrawing due to adverse events. Sildenafil is a well-tolerated oral treatment for erectile dysfunction.
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Ramsay ME, Balogun MA, Collins M, Balraj V. Laboratory surveillance of hepatitis C virus infection in England and Wales: 1992 to 1996. COMMUNICABLE DISEASE AND PUBLIC HEALTH 1998; 1:89-94. [PMID: 9644120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Screening assay for antibody to hepatitis C virus (HCV) became available late in 1990 and their use has subsequently become widespread. Laboratories in England and Wales reported 5232 confirmed HCV infections to the PHLS Communicable Disease Surveillance Centre (CDSC) between 1992 and 1996. Fifty-seven per cent (2976) of reports included risk factor information, 80% of which (2382) identified injecting drug use as the main route of transmission. Thirty-one per cent of reports (1640) included clinical information: 41% (665) were asymptomatic, 57% (938) had symptoms, signs, or biochemical abnormalities of hepatic origin, and 2.2% (37) had non-hepatic conditions. To enhance these data two additional surveys have been undertaken to collect data on all anti-HCV tests performed in public health laboratories. In 1993, a retrospective survey of people tested between 1990 and 1993 revealed that the prevalence of antibody was highest (222/331 [67%]) among injecting drug users and recipients of blood or blood products (189/548 [34%]) and lower among other groups. In a prospective survey of HCV tests performed in transfusion recipients in early 1995, the prevalence of antibody was higher in those transfused before 1985 (11/418 [2.6%]) than in those transfused after 1985 (14/1441 [1.0%]). Reports of confirmed infections are a useful method of monitoring hepatitis C infection but additional data on testing are needed to interpret trends overall and in specific risk groups.
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Brown E, Collins M, Jones C, Meara F, Reid J, Symes J, Thomas C. Awareness campaign to reduce ICU psychosis. Aust Crit Care 1998. [DOI: 10.1016/s1036-7314(98)70471-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Kirk EP, Santa J, Heckler T, Collins M. Obstetrician-gynecologists as primary care physicians: the Oregon experience--early perceptions regarding the effects of legislative action. Am J Obstet Gynecol 1998; 178:1222-8. [PMID: 9662305 DOI: 10.1016/s0002-9378(98)70326-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE Our purpose was to assess whether legislative action influenced the role of obstetrician-gynecologists as primary care physicians. STUDY DESIGN An observational study was performed on the basis of a questionnaire sent to 410 obstetrician-gynecologists and 27 medical directors of managed-care organizations. RESULTS Of 67% of obstetrician-gynecologists and 96% of medical directors who responded, there was agreement as to the content of primary care, but a minority (38%) of obstetrician-gynecologists identified themselves as primary care providers. A minority of medical directors (35%) felt that obstetrician-gynecologists should serve in that role. Both obstetrician-gynecologists and medical directors felt that legislation had little impact. CONCLUSION The reticence of obstetrician-gynecologists to assume a major role in primary care appears to be the result of an uneasiness with accepting a more comprehensive role in patient management and gatekeeping. They appear comfortable with the more traditional roles but feel that training and experience has not prepared them well for the management of more complex medical problems.
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Abstract
The results of alveolar bone grafting carried out at The Hospital for Sick Children, Great Ormond Street, London, UK, between January 1982 and January 1989 were assessed. Cancellous bone from the iliac crest was grafted to alveolar cleft defects in 115 patients (63 male and 52 female). Eighty-seven unilateral (58 left and 29 right) and 28 bilateral clefts were operated on. The mean age at the time of operation was 11.5 years, with a range of 8.08-18.75 years. The cleft canine had erupted prior to bone grafting in 58.4 per cent. At the time of this study the cleft had erupted in 96.35 per cent and was unerupted in 3.65 per cent of sites. Radiographs were taken at regular intervals and assessed according to previously reported criteria. Eighty-six per cent were clinically successful (Type I and II). In Type III 10.95 per cent had less than three-quarters of the normal interdental septal height and 2.18 per cent failed (Type IV). In addition, 3.6 per cent of sites showed cervical root resorption affecting the adjacent incisor and 1.4 per cent internal resorption of the cleft canine.
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Griffiths M, Zahner K, Collins M, Carney L. Masking of irregular corneal topography with contact lenses. THE CLAO JOURNAL : OFFICIAL PUBLICATION OF THE CONTACT LENS ASSOCIATION OF OPHTHALMOLOGISTS, INC 1998; 24:76-81. [PMID: 9571266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
PURPOSE We examined the effectiveness of various types of contact lenses in masking irregular corneal topography using videokeratoscopy, residual aberrations, and measurement of visual acuity. METHODS Thirteen subjects with differing degrees of keratoconus were recruited. Four types of soft lenses were used that varied in both thickness and water content, along with a rigid gas permeable (RGP) and a flexible gas permeable contact lens. RESULTS RGP contact lenses provided the best visual acuity and the least residual aberrations. Flexible gas permeable lenses showed a reasonable masking of corneal distortion but did not provide the expected improvement in visual acuity. Soft contact lenses provided marginally better visual acuity than spectacle correction, but the level of residual aberrations was still high, even for relatively thick soft lenses (up to 0.2 mm). A significant correlation existed between the regularity of the front surface of the contact lenses on the eye and visual acuity in low illumination. CONCLUSIONS Among the currently available contact lens materials, RGP lenses provide the best visual performance for subjects with keratoconus.
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Martin F, Kupsch J, Takeuchi Y, Russell S, Cosset FL, Collins M. Retroviral vector targeting to melanoma cells by single-chain antibody incorporation in envelope. Hum Gene Ther 1998; 9:737-46. [PMID: 9551621 DOI: 10.1089/hum.1998.9.5-737] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Two strategies for targeting recombinant retroviruses to melanoma cells were compared. One was to extend the tropism of an ecotropic envelope to human melanoma cells, the other was to enhance the tropism of an amphotropic envelope for melanoma cells. Chimeric retroviral envelopes, incorporating a single-chain antibody (ScFv) directed against high-molecular-weight melanoma-associated antigen (HMWMAA) at the amino terminus are correctly processed and incorporated into virions. ScFv-ecotropic envelope chimeras allow specific, but low-titer, targeting of HMWMAA-positive cells, when co-expressed with ecotropic envelopes. ScFv-amphotropic envelope chimeras bind specifically to HMWMAA-positive cells and allow preferential infection at high titer.
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MW, Lyberg L, Biemer P, Collins M, dE Leeuw E, Dippo C, Schwarz N, Trewin D. Survey Measurement and Process Quality. J Am Stat Assoc 1998. [DOI: 10.2307/2669667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Pessoa MG, Terrault NA, Detmer J, Kolberg J, Collins M, Hassoba HM, Wright TL. Quantitation of hepatitis G and C viruses in the liver: evidence that hepatitis G virus is not hepatotropic. Hepatology 1998; 27:877-80. [PMID: 9500722 DOI: 10.1002/hep.510270335] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatitis G virus (HGV) is prevalent in patients with chronic liver disease and has been previously detected in liver specimens. However, it is unknown whether the virus is replicating in the liver or is simply a contaminant from serum. We sought to determine whether HGV was hepatotropic and to determine whether coinfection with HGV and hepatitis C virus (HCV) influenced the level of either virus. Virus was quantitated using branched DNA (bDNA) assay for both HGV and HCV in the liver explants and pretransplant serum samples from 30 transplant recipients: Group I, HGV/HCV coinfection (n = 10); group II, HCV infection alone, (n = 8); group III, HGV alone (n = 12). In patients with coinfection HCV (RNA) titers in liver were consistently higher than those for HGV RNA (median 1.13 x 10(8) and 360,000 Eq/g respectively, P < .01). The ratio of liver/serum viral RNA was significantly higher for HCV than for HGV (median 129 and 0.3 respectively, P < .01). Levels of HCV RNA were similar in patients with HCV infection alone versus those with HGV/HCV coinfection (median; liver = 1.15 x 10(7) vs. 1.13 x 10(8) Eq/g, serum = 500,000 vs. 200,000 Eq/mL) and levels of HGV RNA in liver and serum were similar in patients with HGV infection alone compared to those with HGV/HCV coinfection (median; liver = 1.2 x 10(6) vs. 4.0 x 10(5) Eq/g, serum = 4.5 x 106 vs. 2.6 x 10(6) Eq/mL). Levels of either virus appeared unaffected by the presence of an additional virus. The high ratio of HCV RNA levels in liver compared to serum is consistent with its known hepatotropism, but this pattern was not observed for HGV. The median liver/serum ratio of HGV RNA was less than unity, a finding consistent with serum contamination of liver tissue. Thus we conclude that the liver is not the main site of HGV replication.
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Fox WL, O'Rourke PT, Collins M, Gooding K. Encouraging physician leadership. Catholic healthcare systems explore balanced relationships. HEALTH PROGRESS (SAINT LOUIS, MO.) 1998; 79:40-1, 47. [PMID: 10178086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Ziegel ER, Lyberg L, Biemer P, Collins M, de Leeuw E, Dippo C, Schwartz N, Trewin D. Survey Measurement and Process Quality. Technometrics 1998. [DOI: 10.2307/1271416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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289
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Urban JF, Noben-Trauth N, Donaldson DD, Madden KB, Morris SC, Collins M, Finkelman FD. IL-13, IL-4Ralpha, and Stat6 are required for the expulsion of the gastrointestinal nematode parasite Nippostrongylus brasiliensis. Immunity 1998; 8:255-64. [PMID: 9492006 DOI: 10.1016/s1074-7613(00)80477-x] [Citation(s) in RCA: 463] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Although IL-4 induces expulsion of the gastrointestinal nematode parasite, Nippostrongylus brasiliensis, from immunodeficient mice, this parasite is expelled normally by IL-4-deficient mice. This apparent paradox is explained by observations that IL-4 receptor alpha chain (IL-4Ralpha)-deficient mice and Stat6-deficient mice fail to expel N. brasiliensis, and a specific antagonist for IL-13, another activator of Stat6 through IL-4Ralpha, prevents worm expulsion. Thus, N. brasiliensis expulsion requires signaling via IL-4Ralpha and Stat6, and IL-13 may be more important than IL-4 as an inducer of the Stat6 signaling that leads to worm expulsion. Additional observations made in the course of these experiments demonstrate that Stat6 signaling is not required for IL-4 enhancement of IgG1 production and actually inhibits IL-4-induction of mucosal mastocytosis.
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Garner P, Collins M, Cameron K, Bird D. Mobile telecare--a mobile support system to aid the provision of community-based care. J Telemed Telecare 1998; 2 Suppl 1:39-42. [PMID: 9375087 DOI: 10.1258/1357633961929222] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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291
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Charlton MR, Brandhagen D, Wiesner RH, Gross JB, Detmer J, Collins M, Kolberg J, Krom RA, Persing DH. Hepatitis G virus infection in patients transplanted for cryptogenic cirrhosis: red flag or red herring? Transplantation 1998; 65:73-6. [PMID: 9448147 DOI: 10.1097/00007890-199801150-00014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND The significance of hepatitis G (HGV) infection in liver transplant recipients is not known. We set out to determine the pre-orthotopic liver transplantation (OLT) prevalence, the pre- and postoperative viral titers of HGV, and the allograft histology in patients infected with HGV who underwent OLT for cryptogenic cirrhosis. METHODS HGV RNA was measured using a research-based branched DNA assay. The assay used a target-specific probe set that was based on the 5'-untranslated region of the HGV genome. Allograft histology was assessed with protocol liver biopsies in all patients who survived longer than 6 months. RESULTS The preoperative prevalence of HGV infection in recipients transplanted for cryptogenic cirrhosis was 26%. Thirty-seven percent (12 of 33) of recipients who had serum available in the first postoperative month had HGV infection. Mean HGV RNA levels were 9.8 (+/-4.2) (viral molecular equivalents/ml x 10[6]) before OLT and 37.5 (+/-10.7) at 1 year after OLT. In 4 of the 11 cryptogenic recipients in whom HGV RNA was detectable in the first postoperative month, HGV RNA fell to undetectable levels at the most recent follow-up (mean 70 months). Of the five cryptogenic recipients who continue to have measurable HGV RNA, three have unexplained hepatitis histologically. CONCLUSIONS These findings suggest the following: 1) The prevalence of HGV infection in patients undergoing OLT for cryptogenic cirrhosis is about 25%. 2) In recipients persistently infected with HGV, mean HGV RNA titers increase after OLT. 3) HGV RNA becomes undetectable in about one third of recipients who had detectable HGV RNA in the first month after OLT. 4) Hepatitis of uncertain etiology occurs in 60% (3 of 5) of persistently HGV-infected cryptogenic recipients.
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Nicholson LB, Waldner H, Carrizosa AM, Sette A, Collins M, Kuchroo VK. Heteroclitic proliferative responses and changes in cytokine profile induced by altered peptides: implications for autoimmunity. Proc Natl Acad Sci U S A 1998; 95:264-9. [PMID: 9419364 PMCID: PMC18196 DOI: 10.1073/pnas.95.1.264] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/1997] [Accepted: 11/07/1997] [Indexed: 02/05/2023] Open
Abstract
Productive engagement of T cell receptors (TCRs) by cognate ligand (major histocompatibility complex plus peptide) leads to proliferation, differentiation, and the elaboration of effector functions. Altered peptides generated by single amino acid substitutions in the antigenic peptide have diverse effects on the outcome of the T cell response. We have generated an altered peptide (Q144) from an autoantigenic peptide of myelin proteolipid protein 139-151 by a single amino acid substitution (from tryptophan to glutamine) in the primary TCR contact at position 144 that is capable of inducing CD4(+) T cell responses in H-2(s) mice. By using a Q144-specific T cell clone (Q1.1B6), we see a hierarchy in T cell proliferation and cytokine production with various position 144 substituted peptides and have identified a peptide (L144) that hyperstimulates this T cell clone. In contrast to Q144, L144 induces maximal proliferation at 7 logs lower antigen concentration, induces greater cell death at higher antigen dose, and induces the secretion of cytokines not detected following stimulation with the cognate ligand. This heteroclitic T cell response associated with changes in cytokine profile was observed with several other T cell clones of different specificities. The L144 peptide also induces costimulation independent proliferation and cytokine production from the Q1.1B6 T cell clone. We describe this as a superagonist response. Such responses may have a role in the initiation of autoimmunity by promoting a proinflammatory environment following ligation of a cross-reactive TCR on autoreactive T cells.
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Ferguson A, Upledger JE, McPartland JM, Collins M, Lever R. Cranial osteopathy and craniosacral therapy: current opinions. J Bodyw Mov Ther 1998. [DOI: 10.1016/s1360-8592(98)80044-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Dixon WC, Collins M. Screening and chemoprophylaxis for tuberculosis infection in college populations. JOURNAL OF AMERICAN COLLEGE HEALTH : J OF ACH 1998; 46:171-175. [PMID: 9519579 DOI: 10.1080/07448489809595605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Active tuberculosis and the potential for widespread disease exist on college campuses. To maximize the benefit and minimize the potential harm of a screening program, health service clinicians should administer tuberculin skin tests to high-risk students only. Those found to be infected should be considered for prophylactic treatment. The criteria that identify students as being at high risk need to be clearly appreciated, especially the issue of birth outside the United States. Certain countries of origin pose a high risk; others do not. By understanding the fundamentals of the current pandemic and employing a consistent approach, college health professionals can make the correct screening decisions, thereby reducing the risk to their campus communities and assisting in the eradication of this preventable disease.
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Shi Y, Wang R, Sharma A, Gao C, Collins M, Penn L, Mills GB. Dissociation of cytokine signals for proliferation and apoptosis. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1997; 159:5318-28. [PMID: 9548471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Cytokines such as IL-2 or IL-3 prevent cell death through apoptosis, either by preventing apoptosis directly or by sensitizing cells to survival factors present in serum. We demonstrate herein that BAF-B03 cells transfected with the wild-type IL-2R beta-chain undergo apoptosis when stimulated with IL-2 or IL-3 in the absence of serum. IL-2 also induced apoptosis in normal IL-2-responsive human T cell blasts in the absence of serum, and furthermore, epidermal growth factor and fibroblast growth factor induced increased rates of apoptosis in fibroblasts in the absence of serum, suggesting that cytokine-induced apoptosis in the absence of serum survival factors might represent an important biologic phenomenon. In the presence or the absence of serum, IL-2 and IL-3 induced expression of both c-Myc and Bax. In contrast, optimal cytokine-induced expression of Bcl-2 requires serum. Constitutive expression of Bcl-2 prevented cytokine-induced apoptosis. Transferrin mimicked serum by inducing an increase in Bcl-2 expression levels and concurrently prevented apoptosis. These results suggest that the balance between cytokine- and serum-induced Bcl-2 expression and cytokine-induced Bax expression may determine whether a cell undergoes cytokine-induced apoptosis. In BAF/BO3 cells expressing a mutant IL-2Rbeta with a deletion of the acidic domain, IL-2 did not induce either Bax expression or apoptosis. This suggests that the acidic domain of the IL-2R beta-chain plays an essential role in regulating IL-2-mediated Bax expression and apoptosis. Cytokine-induced apoptosis and its counterbalance by survival factors present in serum may play an important role in the regulation of cellular homeostasis during pathophysiologic processes.
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Shi Y, Wang R, Sharma A, Gao C, Collins M, Penn L, Mills GB. Dissociation of cytokine signals for proliferation and apoptosis. THE JOURNAL OF IMMUNOLOGY 1997. [DOI: 10.4049/jimmunol.159.11.5318] [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
Cytokines such as IL-2 or IL-3 prevent cell death through apoptosis, either by preventing apoptosis directly or by sensitizing cells to survival factors present in serum. We demonstrate herein that BAF-B03 cells transfected with the wild-type IL-2R beta-chain undergo apoptosis when stimulated with IL-2 or IL-3 in the absence of serum. IL-2 also induced apoptosis in normal IL-2-responsive human T cell blasts in the absence of serum, and furthermore, epidermal growth factor and fibroblast growth factor induced increased rates of apoptosis in fibroblasts in the absence of serum, suggesting that cytokine-induced apoptosis in the absence of serum survival factors might represent an important biologic phenomenon. In the presence or the absence of serum, IL-2 and IL-3 induced expression of both c-Myc and Bax. In contrast, optimal cytokine-induced expression of Bcl-2 requires serum. Constitutive expression of Bcl-2 prevented cytokine-induced apoptosis. Transferrin mimicked serum by inducing an increase in Bcl-2 expression levels and concurrently prevented apoptosis. These results suggest that the balance between cytokine- and serum-induced Bcl-2 expression and cytokine-induced Bax expression may determine whether a cell undergoes cytokine-induced apoptosis. In BAF/BO3 cells expressing a mutant IL-2Rbeta with a deletion of the acidic domain, IL-2 did not induce either Bax expression or apoptosis. This suggests that the acidic domain of the IL-2R beta-chain plays an essential role in regulating IL-2-mediated Bax expression and apoptosis. Cytokine-induced apoptosis and its counterbalance by survival factors present in serum may play an important role in the regulation of cellular homeostasis during pathophysiologic processes.
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Czerwiec FS, Collins M, Feuillan P, Shenker A. Further study of the therapy for fibrous dysplasia is necessary. J Bone Miner Res 1997; 12:2128-30. [PMID: 9421248 DOI: 10.1359/jbmr.1997.12.12.2128] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Collins M, Easson J, Hansen G, Hodda A, Lewis K. GC-MS-MS confirmation of unusually high delta 9-tetrahydrocannabinol levels in two postmortem blood samples. J Anal Toxicol 1997; 21:538-42. [PMID: 9399122 DOI: 10.1093/jat/21.7.538] [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: 02/05/2023] Open
Abstract
Unusually high levels of delta 9-tetrahydrocannabinol (delta 9-THC) were detected in two postmortem blood samples. Because of sample decomposition, the major metabolite, 11-nor-9-carboxy-tetrahydrocannabinol (delta 9-THCCOOH), could not be determined using the routine EI-MS technique, which cast some doubt on the delta 9-THC result. Analysis of the sample extracts by GC-MS-MS confirmed the presence of delta 9-THC, although no delta 9-THCCOOH was detected.
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Broomall K, Collins M, Smulian AG. Pneumocystis carinii promoter analysis in a heterologous Saccharomyces cerevisiae assay system. J Eukaryot Microbiol 1997; 44:10S-11S. [PMID: 9508404 DOI: 10.1111/j.1550-7408.1997.tb05740.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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McHutchison JG, Nainan OV, Alter MJ, Sedghi-Vaziri A, Detmer J, Collins M, Kolberg J. Hepatitis C and G co-infection: response to interferon therapy and quantitative changes in serum HGV-RNA. Hepatology 1997; 26:1322-7. [PMID: 9362379 DOI: 10.1002/hep.510260534] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Hepatitis G virus (HGV), a positive sense RNA virus, is distantly related to hepatitis C virus (HCV): its genetic organization and identity are consistent with the Flaviviridae family. Coinfection with HGV occurs in 10% to 20% of HCV-infected subjects. These similarities raise two theoretical questions. First, could HGV coinfection play any role in the response of HCV to antiviral therapy and second, would this coinfected population have changes in serum HGV-RNA induced by interferon. To address these questions, 98 patients with documented chronic HCV underwent interferon therapy (3 million units three times a week) for 6 months. Response to therapy was categorized using standard biochemical criteria. Changes in HGV-RNA levels were evaluated before, during, and after interferon therapy by a quantitative branched DNA amplification research-based assay. Eleven of 98 (11%) patients with HCV infection had detectable serum HGV-RNA. There was no difference between the groups (HGV+ vs. HGV-) when baseline alanine aminotransferase (ALT) values, HCV-RNA levels, HCV genotype, histological severity, or other demographic features were analyzed. Interferon response was similar in both groups and HGV was not associated with outcome following therapy. Antiviral therapy appeared to induce a reduction in HGV-RNA load in five of nine patients coinfected with HCV serially tested. In two patients, the fall in serum HGV-RNA correlated with biochemical response, independent of changes in HCV-RNA. These observations indicate that a larger study of an HGV population is required to more clearly define the relationship between HCV and HGV coinfection and their response to antiviral therapy.
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