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Cohen F, Kearney KA, Zegans LS, Kemeny ME, Neuhaus JM, Stites DP. Differential immune system changes with acute and persistent stress for optimists vs pessimists. Brain Behav Immun 1999; 13:155-74. [PMID: 10373279 DOI: 10.1006/brbi.1998.0531] [Citation(s) in RCA: 90] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
This study investigated whether acute and persistent stressors and life change events were followed by changes in immune status, and whether dispositional optimism moderated these relationships. Thirty-nine healthy women ages 18-45 were followed prospectively for 3 months, with weekly assessment of acute and persistent stressors and monthly assessment of life events and immune parameters (NK cell cytotoxicity, and CD4 and CD8 T cell subsets). The study used an autoregressive linear model to examine how weekly appraised acute and persistent stress levels were associated with immune parameters in the subsequent week. Analyses revealed that the immune outcomes were differentially affected by acute and persistent stressors. Further, the association between acute stress and subsequent immune parameters was buffered by an optimistic perspective. However, when stress persisted at high levels, optimists showed more subsequent immune decrements than pessimists.
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Malaterre HR, Cohen F, Kallee K, Deharo JC, Djiane P. Giant interatrial septal aneurysm mimicking a right atrial tumor. INTERNATIONAL JOURNAL OF CARDIAC IMAGING 1998; 14:163-6. [PMID: 9813752 DOI: 10.1023/a:1006052431751] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We report the case of a patient with a giant interatrial septum aneurysm who was admitted to our hospital for analysis of palpitations. Transthoracic echocardiography was not contributive and cardiac magnetic resonance imaging demonstrated a small interatrial septal aneurysm. In our study, only transesophageal echocardiography provided the correct diagnosis, showing a giant interatrial septal aneurysm protruding far away into the right atrium and mimicking a right atrial cystic tumor.
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Kuwatsuru R, Brasch RC, Mühler A, Mathur A, Vexler VS, Rosenau W, Mintorovitch J, Berthezene Y, Cohen F, Shames DM. Definition of liver tumors in the presence of diffuse liver disease: comparison of findings at MR imaging with positive and negative contrast agents. Radiology 1997; 202:131-8. [PMID: 8988202 DOI: 10.1148/radiology.202.1.8988202] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE The potential to define liver tumors at magnetic resonance (MR) imaging was compared with a positive and a negative contrast agent (gadoxetic acid disodium, or gadolinium EOB-DTPA [a hepatocyte-directed agent], and ferumoxides, or superpara-magnetic iron oxide particles [a Kupffer cell-directed agent], respectively) in normal rats and in rats with induced acute hepatitis, fatty liver, or cirrhosis. MATERIALS AND METHODS Rats with implanted liver adenocarcinomas were divided into four groups: no diffuse liver disease ("normal" [n = 6]) and diffuse liver diseases (induced acute hepatitis [n = 6], fatty liver [n = 6], or cirrhosis [n = 6]). Rats first received gadoxetic acid disodium (50 mumol/kg) and then, 45 minutes later, ferumoxides (10 mumol/kg). Liver signal intensity enhancement and tumor-to-liver contrast-to-noise ratio (C/N) were measured in each group. RESULTS Mean liver signal intensity enhancement values with gadoxetic acid disodium and ferumoxides were excellent in the normal liver model (176% and -62%, respectively; P < .01) but were significantly reduced in the acute hepatitis model (82% and -36%, respectively). In the fatty livers compared with the normal livers, enhancement with gadoxetic acid disodium was reduced (57%) but with ferumoxides was excellent (-55%). In the cirrhotic livers compared with the normal livers, enhancement with gadoxetic acid disodium (174%) was virtually the same but was impaired with ferumoxides (-43%). CONCLUSION Hepatic enhancement and tumor-to-liver C/N with either positive or negative liver-enhancing agents can be impaired by the presence of underlying liver disease. Prior knowledge of the type of diffuse liver disease may influence the choice of contrast agent for tumor detection.
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LaMontagne LL, Hepworth JT, Johnson BD, Cohen F. Children's preoperative coping and its effects on postoperative anxiety and return to normal activity. Nurs Res 1996; 45:141-7. [PMID: 8637794 DOI: 10.1097/00006199-199605000-00004] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A model was tested to assess children's preoperative coping with major orthopedic surgery and how coping is related to two different postoperative outcomes, anxiety and return to normal activities. Ninety children, ages 8 to 17, participated. Data were collected the day before surgery, the second postoperative day, and at 3-, 6-, and 9-month recovery periods. A respecified model was not significantly different from the data (p = .90), indicating a good fit. Children who were older, more anxious, and more internal in locus of control exhibited more vigilant coping. Avoidant coping was associated with less anxiety 2 days postoperatively, and vigilant coping was associated with return to normal activities over the course of recovery.
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Bush CE, Donovan RM, Manzor O, Baxa D, Moore E, Cohen F, Saravolatz LD. Comparison of HIV type 1 RNA plasma viremia, p24 antigenemia, and unintegrated DNA as viral load markers in pediatric patients. AIDS Res Hum Retroviruses 1996; 12:11-5. [PMID: 8825613 DOI: 10.1089/aid.1996.12.11] [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
Better surrogate markers need to be developed to evaluate therapy in HIV-infected children. This study evaluated plasma RNA, immune complex-dissociated p24 antigenemia, and unintegrated DNA (uDNA) in HIV-infected pediatric patients. Ten children were followed from initiation of nucleoside antiretroviral therapy at intervals up to 24 months. Prior to initiation of therapy, HIV RNA was detected in 10 of 10 patients (median, 76,000 Eq/ml), p24 antigen was detected in 8 of 10 patients (median, 193 pg/ml), and uDNA was detected in 6 of 7 patients (median, 10% uDNA). After 12 months the RNA decreased in all patients and became undetectable in six. In contrast, p24 antigenemia decreased in 6 of 10 patients, remained undetectable in 1, and increased in 3. HIV uDNA decreased in six of six patients and became undetectable in three. There was no overall change in CD4 cell count. Plasma RNA and uDNA levels are both sensitive markers of nucleoside therapy in children; however, they do not covary strongly.
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Boyce WT, Adams S, Tschann JM, Cohen F, Wara D, Gunnar MR. Adrenocortical and behavioral predictors of immune responses to starting school. Pediatr Res 1995; 38:1009-17. [PMID: 8618776 DOI: 10.1203/00006450-199512000-00030] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Associations between major psychologic stressors and immune function have been documented in previous research, but few studies have investigated immune changes attending minor, normative stressors. This study examined adrenocortical and behavioral predictors of immune responses to starting kindergarten in 39 five-year-old children, who completed laboratory visits for venipunctures 1 wk before (time 1) and 1 wk after (time 2) school entry. At time 1, children were also immunized with pneumococcal vaccine. Immune responses were measured as change scores for T (CD4+ and CD8+) cells, B (CD19+) cells, lymphoproliferative responses to pokeweed mitogen (PWM), and type-specific pneumococcal antibody responses (ABR). Adrenocortical response was assessed as the change in salivary cortisol level, and behavioral difficulty with school adjustment was scored using parental ratings of behavior problems, stress due to changes in routines, and degree of adaptive challenge. Salivary cortisol rose after kindergarten entry (means = 0.39 +/- 0.28 to 0.49 +/- 0.36 micrograms/dL, p = 0.03) and was unrelated to behavioral difficulties. CD4+ cells increased in number, whereas PWM declined, and CD19+ cells showed a borderline increase. Change in salivary cortisol was positively associated with change in CD19+ (delta CD19+) and inversely related to ABR. Scores for behavioral difficulty were inversely associated with delta CD4+ and delta CD19+. These data suggest that: 1) school entry is a stressor capable of evoking elevations in cortisol and behavior problems, accompanied by shifts in functional and enumerative measures of immune status; and 2) children with greater adrenocortical reactivity have increases in B cell numbers and less effective B cell-mediated antibody production, whereas children with more behavioral difficulties show declines in all T and B cell subsets.
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Boyce WT, Chesney M, Alkon A, Tschann JM, Adams S, Chesterman B, Cohen F, Kaiser P, Folkman S, Wara D. Psychobiologic reactivity to stress and childhood respiratory illnesses: results of two prospective studies. Psychosom Med 1995; 57:411-22. [PMID: 8552730 DOI: 10.1097/00006842-199509000-00001] [Citation(s) in RCA: 224] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Psychological stress is thought to undermine host resistance to infection through neuroendocrine-mediated changes in immune competence. Associations between stress and infection have been modest in magnitude, however, suggesting individual variability in stress response. We therefore studied environmental stressors, psychobiologic reactivity to stress, and respiratory illness incidence in two studies of 236 preschool children. In Study 1, 137 3- to 5-year-old children from four childcare centers underwent a laboratory-based assessment of cardiovascular reactivity (changes in heart rate and mean arterial pressure) during a series of developmentally challenging tasks. Environmental stress was evaluated with two measures of stressors in the childcare setting. The incidence of respiratory illnesses was ascertained over 6 months using weekly respiratory tract examinations by a nurse. In Study 2, 99 5-year-old children were assessed for immune reactivity (changes in CD4+, CD8+, and CD19+ cell numbers, lymphocyte mitogenesis, and antibody response to pneumococcal vaccine) during the normative stressor of entering school. Blood for immune measures was sampled 1 week before and after kindergarten entry. Environmental stress was indexed with parent reports of family stressors, and a 12-week respiratory illness incidence was measured with biweekly, parent-completed symptom checklists. The two studies produced remarkably similar findings. Although environmental stress was not independently associated with respiratory illnesses in either study, the incidence of illness was related to an interaction between child care stress and mean arterial pressure reactivity (beta = .35, p < .05) in Study 1 and to an interaction between stressful life events and CD19+ reactivity (beta = .51, p < .05) in Study 2.(ABSTRACT TRUNCATED AT 250 WORDS)
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Bergman M, Cohen F, Schlesinger H, Kessler-Icekson G. Effects of amiodarone on beating rate and Na-K-ATPase activity in cultured neonatal rat heart myocytes. GENERAL PHARMACOLOGY 1995; 26:285-90. [PMID: 7590075 DOI: 10.1016/0306-3623(94)00178-p] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
1. The purpose of this study was to examine the possibility that the cellular action of amiodarone is mediated by inhibition of thyroid hormone regulatory functions within the myocardial cell. We measured the rate of cell beating and the activity of Na-K-ATPase in cultured neonatal rat heart myocytes. 2. Amiodarone (0.25 and 1 microgram/ml) reduced beating rate up to 75% within 20 min, and Na-K-ATPase activity up to 40% within 2 hr. No toxic effects were detected in the treated cells. 3. The inhibitory actions of amiodarone on beating rate and Na-K-ATPase activity were the same in myocytes grown in the presence or absence of 3-iodothyronine (T3, 5 nM). 4. These data indicate that amiodarone affects beating rate and Na-K-ATPase activity independently of thyroid hormone. It is suggested that interference of amiodarone with thyroid hormone action is not the only mechanism by which this drug modulates some functions of the myocardial cell.
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Birdsall NJ, Cohen F, Lazareno S, Matsui H. Allosteric regulation of G-protein-linked receptors. Biochem Soc Trans 1995; 23:108-11. [PMID: 7758667 DOI: 10.1042/bst0230108] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
MESH Headings
- Allosteric Regulation
- Allosteric Site
- Animals
- GTP-Binding Proteins/metabolism
- Humans
- Ligands
- Receptors, Adrenergic, alpha-2/chemistry
- Receptors, Adrenergic, alpha-2/metabolism
- Receptors, Muscarinic/chemistry
- Receptors, Muscarinic/metabolism
- Receptors, Neurotransmitter/chemistry
- Receptors, Neurotransmitter/metabolism
- Receptors, Purinergic P1/chemistry
- Receptors, Purinergic P1/metabolism
- Recombinant Proteins/chemistry
- Recombinant Proteins/metabolism
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Isobe H, Sridhar KS, Doria R, Cohen F, Raub WA, Saldana M, Krishan A. Prognostic significance of DNA aneuploidy in diffuse malignant mesothelioma. CYTOMETRY 1995; 19:86-91. [PMID: 7705189 DOI: 10.1002/cyto.990190111] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
DNA ploidy of pepsin digested preparations of 48 paraffin-embedded specimens from 19 patients with histologically confirmed malignant mesothelioma was determined by laser flow cytometry. Eight of the 19 tumors (42%) were diploid and 11 (58%) were aneuploid. Of the aneuploid tumors, only one showed multiploidy. The median survival time of the patients with diploid tumors was 19, 16, and 14 months from the onset of symptoms, diagnosis, and treatment, respectively. The median survival in patients with aneuploid tumors was 8, 7, and 7 months from the onset of first symptoms, diagnosis, and treatment. Thus, patients with diploid tumors lived longer than patients with aneuploid tumors. These results suggest that DNA ploidy analysis may be of prognostic value in malignant mesothelioma.
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Donovan RM, Bush CE, Smereck SM, Moore E, Cohen F, Saravolatz LD. Antiretroviral therapy is associated with a decrease in unintegrated HIV-1 DNA in pediatric patients. JOURNAL OF ACQUIRED IMMUNE DEFICIENCY SYNDROMES 1994; 7:1237-41. [PMID: 7965634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Good markers for monitoring the efficacy of antiretroviral therapy in children do not currently exist. This study examined the effect of antiretroviral therapy on human immunodeficiency virus (HIV-1) unintegrated DNA (uDNA), integrated DNA (iDNA), percent uDNA, immune complex dissociated (ICD) p24 antigenemia, and plasma viral titer. Seven children were followed at therapy initiation and at approximately 3- and 10-month intervals. HIV-1 uDNA was detected in all children prior to start of therapy (average percent uDNA, 43%). At 3 months, the percent HIV uDNA decreased in all patients to an average of 18% (p = 0.01) and at 10 months decreased to an average of 1%. In contrast, the amount of HIV iDNA was relatively constant after initiation of therapy. ICD HIV p24 antigen was detected in all patients prior to therapy (average, 538 pg/ml). Over the study period, the ICD p24 antigen level decreased in three patients and remained relatively unchanged in four patients. Plasma cultures of HIV-1 were positive in only one of the seven patients prior to therapy. Among the methods evaluated, measurement of uDNA was the only parameter which reliable decreased after initiation of nucleoside therapy.
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Kuwatsuru R, Liu T, Cohen F, Shames DM, Osorio RW, Mann J, Rosenau W, Mühler A, Neuder MS, Roberts JP. Acute liver transplantation rejection. Early detection of endothelial leak in a rat model using magnetic resonance imaging and a macromolecular contrast medium. Invest Radiol 1994; 29 Suppl 2:S297-9. [PMID: 7928261 DOI: 10.1097/00004424-199406001-00102] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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Boyce WT, Chesterman EA, Martin N, Folkman S, Cohen F, Wara D. Immunologic changes occurring at kindergarten entry predict respiratory illnesses after the Loma Prieta earthquake. J Dev Behav Pediatr 1993; 14:296-303. [PMID: 8254059] [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: 01/29/2023]
Abstract
Previous studies in adult populations have demonstrated alterations in immune function after psychologically stressful events, and pediatric research has shown significant associations between stress and various childhood morbidities. However, no previous work has examined stress-related immune changes in children and subsequent illness experience. Twenty children were enrolled in a study on immunologic changes after kindergarten entry and their prospective relationship to respiratory illness (RI) experience. Midway through a 12-week RI data collection period, the October 17, 1989 Loma Prieta earthquake occurred. The timing of this event created a natural experiment enabling us to study possible associations between immunologic changes at kindergarten entry, the intensity of earthquake-related stress for children and parents, and changes in RI incidence over the 6 weeks after the earthquake. Immunologic changes were measured using helper (CD4+)-suppressor (CD8+) cell ratios, lymphocyte responses to pokeweed mitogen, and type-specific antibody responses to Pneumovax, in blood sampled 1 week before and 1 week after school entry. RI incidence was assessed using home health diaries and telephone interviews completed every 2 weeks. RIs per child varied from none to six. Six children showed an increase in RI incidence after the earthquake; five experienced a decline. Changes in helper-suppressor cell ratios and pokeweed mitogen response predicted changes in RI incidence in the postearthquake period (r = .43, .46; p < .05). Children showing upregulation of immune parameters at school entry sustained a significant increase in RI incidence after the earthquake.(ABSTRACT TRUNCATED AT 250 WORDS)
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Weaver DD, Baker D, Theobald M, Cohen F, King RA, Krueger S, Laxova R, Lubinsky MS. Minimum guidelines for the delivery of clinical genetics services. The Evaluation of Clinical Services Subcommittee, Great Lakes Regional Genetics Group. Am J Hum Genet 1993; 53:287-9. [PMID: 8317494 PMCID: PMC1682236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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Jarvis JN, Taylor H, Iobidze M, Dejonge J, Chang S, Cohen F. Rheumatoid factor expression and complement activation in children congenitally infected with human immunodeficiency virus. CLINICAL IMMUNOLOGY AND IMMUNOPATHOLOGY 1993; 67:50-4. [PMID: 8443984 DOI: 10.1006/clin.1993.1044] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Rheumatic disease manifestations and autoimmune phenomena are common in adults infected with human immunodeficiency virus (HIV). On the other hand, rheumatic disease manifestations are rare in children congenitally infected with HIV. We studied the relationship between autoimmune phenomena and rheumatic diseases by examining HIV-infected children for the presence of rheumatoid factors (RFs), immune complexes, and complement activation fragments. RFs (principally IgA) were detected in 12 of the 24 HIV-infected patients (50%) and in none of the uninfected (HIV-exposed, seroreverted) controls (n = 22). Mean levels of complement activation fragments C3a and Bb were elevated in the HIV-infected children compared with the controls. A correlation was seen between the presence of IgA RF and alternative complement pathway activation as measured by plasma levels of Bb. None of the children had clinical or laboratory evidence of rheumatic disease.
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Cohen F, Valleur P, Serra J, Brisset D, Chiche L, Hautefeuille P. Relationship between gastric acid secretion and the rate of recurrent ulcer after parietal cell vagotomy. Ann Surg 1993; 217:253-9. [PMID: 8452404 PMCID: PMC1242778 DOI: 10.1097/00000658-199303000-00007] [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: 01/30/2023]
Abstract
OBJECTIVE This study assessed the effect of gastric secretion on the rate of recurrent ulcer after parietal cell vagotomy for duodenal ulcer. SUMMARY BACKGROUND DATA Three hundred patients who underwent parietal cell vagotomy for duodenal ulcer between 1975 and 1986 were evaluated. The mean follow-up period for 280 patients was 5 years. METHODS The gastric secretion tests concerned basal acid output (BAO) and peak acid output stimulated by pentagastrin or insulin. Tests were preoperative for 172 patients and postoperative for 118. RESULTS At the end of that time, the overall incidence of symptomatic recurrent ulcer was 15%. Two criteria were shown to be important predictors of recurrent ulcer: preoperative BAO > 7 mmol/hr, for which the recurrence rate 5 years after vagotomy was 30% versus 11% for values below this threshold (p = 0.01), and postoperative BAO > 1.4 mmol/hr, for which the recurrence rate at 5 years was 72% versus 8% for lower values (p = 0.0001). All patients with recurrent ulcer had either a postoperative BAO > 7 mmol/hr and/or a postoperative reduction in BAO < 80%. CONCLUSION Preoperative BAO > 7 mmol/hr and postoperative BAO > 1.4 mmol/hr were shown to be factors predictive of RU. All patients with RU presented either with preoperative BAO > 7 mmol/hr and/or a reduction in BAO < 80%. Consequently, in our opinion, these criteria could be used either to select patients for vagotomy or to assess the effectiveness of vagotomy of different types, especially those performed by celioscopy.
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Gasset M, Baldwin MA, Lloyd DH, Gabriel JM, Holtzman DM, Cohen F, Fletterick R, Prusiner SB. Predicted alpha-helical regions of the prion protein when synthesized as peptides form amyloid. Proc Natl Acad Sci U S A 1992; 89:10940-4. [PMID: 1438300 PMCID: PMC50458 DOI: 10.1073/pnas.89.22.10940] [Citation(s) in RCA: 262] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
By comparing the amino acid sequences of 11 mammalian and 1 avian prion proteins (PrP), structural analyses predicted four alpha-helical regions. Peptides corresponding to these regions of Syrian hamster PrP were synthesized, and, contrary to predictions, three of the four spontaneously formed amyloids as shown by electron microscopy and Congo red staining. By IR spectroscopy, these amyloid peptides exhibited secondary structures composed largely of beta-sheets. The first of the predicted helices is the 14-amino acid peptide corresponding to residues 109-122; this peptide and the overlapping 15-residue sequence 113-127 both form amyloid. The most highly amyloidogenic peptide is AGAAAAGA, which corresponds to Syrian hamster PrP residues 113-120 and is conserved across all species for which the PrP sequence has been determined. Two other predicted alpha-helices corresponding to residues 178-191 and 202-218 form amyloids and exhibit considerable beta-sheet structure when synthesized as peptides. These findings suggest the possibility that the conversion of the cellular isoform of PrP to the scrapie isoform of PrP involves the transition of one or more putative PrP alpha-helices into beta-sheets and that prion diseases are disorders of protein conformation.
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Cohen F, Goumont R, Rudler H, Daran J, Toscano R. Dihydropyridine-induced reductions of methyl(ethoxy)carbene complexes of chromium and tungsten: Formation and x-ray crystal structure of the adduct between pyridine and the corresponding ethylidene carbene complexes. J Organomet Chem 1992. [DOI: 10.1016/0022-328x(92)83292-p] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Moore EC, Cohen F, Douglas SD, Gutta V. Staphylococcal infections in childhood dermatomyositis--association with the development of calcinosis, raised IgE concentrations and granulocyte chemotactic defect. Ann Rheum Dis 1992; 51:378-83. [PMID: 1575586 PMCID: PMC1004666 DOI: 10.1136/ard.51.3.378] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
There is a high incidence of staphylococcal infection in children with dermatomyositis, which is limited to those children who either already have or subsequently develop calcinosis. Of 15 children followed up for 3-10 years after diagnosis, all nine who developed calcinosis had infections with Staphylococcus aureus compared with none of six without calcinosis. Of these nine, the occurrence of staphylococcal infections before calcinosis was observed in four, suggested by history in two, and unclear in three children. Granulocyte chemotaxis to Staphylococcus aureus was more severely depressed in those children with calcinosis, whereas those without calcinosis did not differ significantly from controls. The chemotactic defect was due to a serum factor (patients' serum depressed control chemotaxis and control serum corrected the patients' chemotaxis). The nine children with calcinosis also had significantly higher serum IgE concentrations than non-atopic age matched controls; the six without calcinosis did not differ from controls. The increased IgE concentrations appeared to develop after staphylococcal infection and before calcinosis. Two of five patients with calcinosis had increased antistaphylococcal IgE antibodies; neither of the two patients without calcinosis had such increased antibodies. This suggests preceding immunological differences in patients with dermatomyositis who do and do not subsequently develop calcinosis, either increasing susceptibility to Staphylococcus aureus infection or potentially resulting from such infections.
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Moore EC, Cohen F, Farooki Z, Chang CH. Focal scleroderma and severe cardiomyopathy. Patient report and brief review. AMERICAN JOURNAL OF DISEASES OF CHILDREN (1960) 1991; 145:229-31. [PMID: 1994694 DOI: 10.1001/archpedi.1991.02160020123031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A 21-month-old infant presented with simultaneous localized scleroderma and severe cardiomyopathy with heart failure. Cardiac abnormalities and serological changes (positive rheumatoid factor assay, elevated IgM and IgG levels, and elevated erythrocyte sedimentation rate) reverted to normal with prednisone therapy, and there was substantial, though incomplete, resolution of her skin changes during the same period. To our knowledge, this is the first patient with definite, clinically significant cardiac involvement associated with focal scleroderma. The possibility of internal organ involvement, including cardiac involvement, must be considered with focal scleroderma as well as with progressive systemic sclerosis.
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Moore EC, Cohen F, Kauffman RE, Aravind MK. Zidovudine overdose in a child. N Engl J Med 1990; 322:408-9. [PMID: 2300100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Roifman CM, Hummel D, Martinez-Valdez H, Thorner P, Doherty PJ, Pan S, Cohen F, Cohen A. Depletion of CD8+ cells in human thymic medulla results in selective immune deficiency. J Exp Med 1989; 170:2177-82. [PMID: 2511270 PMCID: PMC2189543 DOI: 10.1084/jem.170.6.2177] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
CD8 molecules expressed on the surface of a subset of T cells participate in the selection of class I MHC antigen-restricted T cells in the thymus, and in MHC-restricted immune responses of mature class I MHC antigen-restricted T cells. Here we describe an immune-deficient patient with lack of CD8+ peripheral blood cells. The patient presented with Pneumocystis carinii pneumonia and was unable to reject an allogeneic skin graft, but had normal primary and secondary antibody responses. Examination of the patient's thymus revealed that the loss of CD8+ cells occurred during intrathymic differentiation: the patient's immature cortical thymocytes included both CD4+ and CD8+ cells while the mature medullary cells expressed the CD4 but not the CD8 protein on their surface. Northern blot and polymerase chain reaction analyses revealed the presence of CD8 alpha and beta mRNA in the patient's thymus but not in the peripheral blood. Both class I MHC antigen expression and the expressed TCR V beta repertoire are normal in this patient. These data are consistent with an impaired selection of CD8+ cells in the patient's thymus and support the role of the CD8 surface protein in thymic selection previously characterized in genetically manipulated and inbred mice.
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Holm K, Cohen F, Dudas S, Medema PG, Allen BL. Effect of personal pain experience on pain assessment. IMAGE--THE JOURNAL OF NURSING SCHOLARSHIP 1989; 21:72-5. [PMID: 2731953 DOI: 10.1111/j.1547-5069.1989.tb00101.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The purpose of this study was to determine the effect of nurses' personal pain experiences on the assessment of their patients' pain. The sample consisted of 134 registered nurses employed in three Midwestern hospitals. In response to a personal pain history questionnaire, pain with headache, menstrual distress and dental events were cited most frequently. Most also reported that a family member had experienced pain in their presence (cancer, surgery, orthopedic injuries). Responses to the Standard Measure of Inferences of Suffering (Davitz & Davitz, 1981) showed significant differences between intensity of pain experienced by the nurse and overall perceived patient psychological distress. Furthermore, the intensity of pain experienced by the nurse was the only variable that predicted significantly perceptions of patients' physical suffering and psychological distress. While additional study is warranted, the findings support the notion that nurses who have experienced intense pain are more sympathetic to the patient in pain.
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Abstract
The relationships among stressful life experience, mood, helper-inducer (CD4+) and suppressor-cytotoxic (CD8+) T cells and genital herpes simplex virus (HSV) recurrence were investigated prospectively in 36 patients with recurrent HSV. The following factors were measured monthly for six months: stressful life experience (including current acute and ongoing stressors, residual effects of previous stressors, and anticipation of future stressors), negative mood, health behaviors, other possible HSV triggers, HSV recurrences, and the proportion of CD4+ and CD8+ cells (in half the sample). Results averaging monthly scores over the six-month study period indicated that: 1) subjects with high levels of stressful experience had a lower proportion of both CD4+ and CD8+ cells, 2) subjects with high levels of depressive mood, anxiety, or hostility had a lower proportion of CD8+ cells, and 3) subjects with high levels of depressive mood who did not report many symptoms of other infections had a higher rate of HSV recurrence. A model is proposed linking depressive mood, CD8+ cells, and HSV recurrence.
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Cohen F, Lasfargues JJ. Quantitative chemical study of root canal preparations with calcium hydroxide. ENDODONTICS & DENTAL TRAUMATOLOGY 1988; 4:108-13. [PMID: 3248572 DOI: 10.1111/j.1600-9657.1988.tb00306.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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