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Johnson TR, Hoch M, Huber A, Römer U, Reiser MF, Schönberg SO, Netz H. Quantifizierung der rechtsventrikulären Funktion bei angeborenen Herzfehlern: Korrelation von 3D-Echokardiographie und MRT als sich ergänzende Methoden. ROFO-FORTSCHR RONTG 2006; 178:1014-21. [PMID: 17021980 DOI: 10.1055/s-2006-926945] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
PURPOSE In congenital heart disease, the exact determination of the right ventricular function is of high importance for therapeutic and especially surgical planning. The aim of this study was to correlate the parameters of the right ventricular function in MRI and 3D echocardiography to determine the agreement of both modalities. MATERIALS AND METHODS In 18 patients suffering from congenital heart disease, 3D echocardiography was performed using a Philips Sonos 7500 system. In MRI short axis slices with a 4-mm distance were acquired using an SSFP sequence on a Siemens Sonata or Symphony System. Volumetry for both modalities was performed on an external workstation (Tomtec) using the EchoView software. RESULTS Enddiastolic and endsystolic volumes showed a highly significant correlation with coefficients of 0.996 and 0.990, respectively. In echocardiography there was a systematic slight underestimation of enddiastolic volumes and overestimation of endsystolic volumes. The Wilcoxon test did not show significant differences between the volumes and ejection fractions assessed by both modalities. CONCLUSION There is an excellent correlation in the quantification of right ventricular volumes in MRI and 3D echocardiography, which allows a comparison of acquired volumes in clinical follow-up.
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Gould WR, McClanahan TB, Welch KM, Baxi SM, Saiya-Cork K, Chi L, Johnson TR, Leadley RJ. Inhibitors of blood coagulation factors Xa and IIa synergize to reduce thrombus weight and thrombin generation in vivo and in vitro. J Thromb Haemost 2006; 4:834-41. [PMID: 16634754 DOI: 10.1111/j.1538-7836.2006.01830.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Many compounds currently in development for treatment of thrombotic disorders demonstrate high specificity for single targets of blood coagulation such as factor Xa (FXa) or thrombin. AIM The aim of this study is to determine if inhibition of both FXa and thrombin by simultaneous administration of PD0313052 and argatroban, respectively, synergistically increases the effect of either drug alone in vivo and in vitro. METHODS AND RESULTS Analyses of thrombin generation from combined inhibition in human plasma using statistical methods of Bliss independence identified a synergistic reduction in thrombin production 30% lower than predicted by simple additivity. The greatest synergy occurred at concentrations of each compound below their individual IC50 values. In a rabbit arterio-venous shunt model (RAV) of thrombosis, co-administration of PD0313052 and argatroban reduced thrombus weight (TW) to a much greater degree than expected by additivity alone producing a synergistic decrease of 45% over the level predicted by additivity. Analyses of thrombin generation in plasma samples from the RAV also demonstrated 38% synergy ex vivo. Furthermore, at plasma concentrations with the greatest synergistic effect, no increase in bleeding or appreciable change in prothrombin time, activated partial thromboplastin time, or activated clotting time was observed, but thrombus weight reduction was greater than twofold higher than that expected from simple additivity. CONCLUSIONS These results demonstrate a significant synergistic antithrombotic effect of combining low doses of PD0313052 and argatroban and support the hypothesis that simultaneous targeting of multiple coagulation enzymes may offer an improved therapeutic index in the prevention and treatment of thrombosis.
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Batra AS, Chun DS, Johnson TR, Maldonado EM, Kashyap BA, Maiers J, Lindblade CL, Rodefeld M, Brown JW, Hubbard JE. A prospective analysis of the incidence and risk factors associated with junctional ectopic tachycardia following surgery for congenital heart disease. Pediatr Cardiol 2006; 27:51-55. [PMID: 16391972 DOI: 10.1007/s00246-005-0992-6] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This study was designed to evaluate the incidence and risk factors associated with the occurrence of junctional ectopic tachycardia (JET) in patients after congenital heart surgery. We prospectively analyzed cardiac rhythm status in 336 consecutive patients undergoing surgery for congenital heart disease at our institution during a 1-year period. The incidence of JET was 8% (27/336). Repairs with the highest incidence of JET were arterial switch operation (3/13, 23%), atrioventricular (AV) canal repair (4/19, 21%), and Norwood repair (2/10, 20%). Compared to patients with no arrhythmias, patients with JET were more likely to be younger (2.75 +/- 2.44 vs 5.38 +/- 7.25 years, p < 0.01), have had longer cardiopulmonary bypass times (126 +/- 50 vs 85 +/- 73, p < 0.01), and have a higher inotrope score (6.26 +/- 7.55 vs 2.41 +/- 8.11, p < 0.01). By multivariate analysis, ischemic time was the only factor associated with JET [odds ratio, 1.01 (confidence interval, 1.005-1.02); p = 0.0014). The presence of JET did not correlate with electrolyte abnormalities. JET is not necessarily related to surgery near the His bundle or hypomagnesemia. Longer ischemic time is the best predictor of JET. Patients undergoing arterial switch operation, AV canal repair, and Norwood repair are at highest risk of postoperative JET and should be considered for prophylactic therapy.
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Sandouka A, Balogun E, Foresti R, Mann BE, Johnson TR, Tayem Y, Green CJ, Fuller B, Motterlini R. Carbon monoxide-releasing molecules (CO-RMs) modulate respiration in isolated mitochondria. Cell Mol Biol (Noisy-le-grand) 2005; 51:425-32. [PMID: 16309593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2005] [Accepted: 04/18/2005] [Indexed: 05/05/2023]
Abstract
Emerging evidence reveals that heme oxygenase-1 (HO-1) and its product carbon monoxide (CO) can exert diverse biological and cytoprotective effects. Our group has recently identified a new class of compounds (CO-releasing molecules or CO-RMs) that can carry and deliver CO to biological systems and can be used to examine the physiological properties of CO. Here, we evaluated the influence of endogenously-generated CO (via HO-1 induction by hemin) and CO liberated from exogenously supplied CO-RMs on mitochondrial function. Renal mitochondria were isolated either from rats with increased HO-1 or from untreated animals, the latter being exposed to different concentrations of CO-RMs (10-100 microM). We found that mitochondrial oxygen uptake was significantly reduced in kidneys after HO-1 induction and, in a similar fashion, CO-RMs inhibited mitochondrial function in a concentration-dependent manner. Specifically, a marked depression of state 3 was observed resulting in a significant decrease in respiratory control index (RCI) values. When mitochondria were incubated with the inactive forms of CO-RMs, which are devoid of CO, the respiratory parameters remained unchanged. In summary, the results indicate that HO-1 induction and enhanced CO decrease renal oxygen consumption and alter mitochondrial function suggesting that CO could be a physiological regulator of mitochondrial oxidative phosphorylation.
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Foresti R, Shurey C, Ansari T, Sibbons P, Mann BE, Johnson TR, Green CJ, Motterlini R. Reviewing the use of carbon monoxide-releasing molecules (CO-RMs) in biology: implications in endotoxin-mediated vascular dysfunction. Cell Mol Biol (Noisy-le-grand) 2005; 51:409-23. [PMID: 16309592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2005] [Accepted: 05/30/2005] [Indexed: 05/05/2023]
Abstract
The inducible stress protein heme oxygenase-1 (HO-1) has been linked to tissue and organ protection against the deleterious actions of many pathological conditions, including endotoxin challenge. Similar protection can be achieved by the main products of heme oxygenase activity, namely bilirubin and carbon monoxide (CO). Since the identification of novel chemical compounds that liberate CO in biological systems (CO-releasing molecules or CO-RMs), our group and others have had access to a convenient and simple pharmacological tool that enables to study the role of CO in physiological functions. This article will review the scientific literature published to date on CO-RMs, with emphasis on the in vitro, ex vivo and in vivo experimental models employed to determine the contribution of CO to cellular mechanisms. In addition, we will report on the effect of heme oxygenase-related substances, such as bilirubin, CORM-3 and hemin, in a model of endotoxin-induced hypotension. Among the three different approaches examined, CORM-3 proved the most effective agent in reducing the fall in blood pressure caused by endotoxin. Furthermore, heme oxygenase-related substances affected the endotoxin-stimulated induction and distribution of hepatic HO-1 and inducible nitric oxide synthase (iNOS). Thus, it emerges that CO-RMs could exert important biological actions in the context of endotoxic-mediated dysfunction.
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Johnson TR, Kim JS. A generalized estimating equations approach to mixed-effects ordinal probit models. THE BRITISH JOURNAL OF MATHEMATICAL AND STATISTICAL PSYCHOLOGY 2004; 57:295-310. [PMID: 15511310 DOI: 10.1348/0007110042307177] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Clustered ordinal responses, which are commonplace in behavioural and educational research, are often analysed using mixed-effects ordinal probit models. Likelihood-based inference for these models can be computationally burdensome, and may compromise the consistency of estimators if the model is misspecified. We propose an alternative inferential approach based on generalized estimating equations. We show that systems of estimating equations can be specified for mixed-effects ordinal probit models that avoid the potentially heavy computational demands of maximum likelihood estimation, and can also provide inferences that are robust with respect to some forms of model misspecification--particularly serial effects in longitudinal data.
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McPhee SD, Johnson TR, Dietrich MS. Comparing health status with healthy habits in elderly assisted-living residents. FAMILY & COMMUNITY HEALTH 2004; 27:158-169. [PMID: 15596983 DOI: 10.1097/00003727-200404000-00009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
There is a growing number of older adults in America. Assisted-living facilities have become a more prevalent residence for this increasing population. In the study described in this article, a secondary data analysis was completed using residents of several LifeTrust America, Inc.,'s assisted-living facilities across the Southeastern United States. There were 1,079 residents who completed the Healthy Generation Survey. Residents were asked whether they currently, previously, or had never had certain health conditions. They also responded to various questions about their current participation in healthy habits, such as using cigarette or tobacco products, moderate alcohol consumption, eating breakfast, eating healthy snacks, getting 7-8 hours of sleep each night, drinking the daily recommended amount of water, and participating in regular physical exercise. The research question asked if there was a relationship between current healthy habits and physical health. The study found that individuals with more current physical health conditions also reported greater participation in healthy habits. This could lead to the conclusion that after individuals acquired certain physical health conditions, they began to participate in more healthy habits. Also of significance was the finding that participation in physical exercise and recreational activity related to greater participation in all other healthy habits.
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Feresu SA, Harlow SD, Gillespie BW, Welch K, Johnson TR. Birthweight-adjusted Dubowitz methods: reducing misclassification of assessments of gestational age in a Zimbabwean population. THE CENTRAL AFRICAN JOURNAL OF MEDICINE 2003; 49:47-53. [PMID: 15214282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
OBJECTIVE To evaluate the performance and the utility of using birthweight-adjusted scores of the Dubowitz method of estimating gestational age in a Zimbabwean population. DESIGN A validation study. SETTING Harare Maternity Hospital, from October to December 1999. SUBJECTS 364 African newborn infants with a known last menstrual period (LMP), within the first 56 hours of life. MAIN OUTCOME MEASURES Differences between regression lines and variances explained by Dubowitz scores obtained by examining newborn infants compared to gestational age calculated from the last menstrual period, in models with and without the addition of birthweight. RESULTS The Dubowitz method was a good predictor of gestational age, useful in differentiating term from pre-term infants. The beta coefficients from regression lines with and without addition of birthweight differed significantly from each other (z = 2.83, p < 0.01). Our regression line without adding birthweight was Y(LMP gestational age) = 23.814 + 0.301* score. Addition of birthweight to the regression models improved prediction of gestational age, Y(LMP gestational age) = 23.512 + 0.219* score + 0.0015* grams, and accounted for 69% of the variance compared to 66% in models without birthweight. CONCLUSION The introduction of birthweight improves estimation of gestational age, correcting for the overestimation reported for the original Dubowitz methods and the error caused by low birthweight. We recommend the use of our birthweight-adjusted Dubowitz maturity scales for studies of prematurity, and for routine clinical practice.
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Budescu DV, Kuhn KM, Kramer KM, Johnson TR. Erratum to “Modeling certainty equivalents for imprecise gambles” [Organizational Behavior and Human Decision Processes 88 (2002) 748–768]. ORGANIZATIONAL BEHAVIOR AND HUMAN DECISION PROCESSES 2002. [DOI: 10.1016/s0749-5978(02)00041-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Budescu DV, Kuhn KM, Kramer KM, Johnson TR. Modeling certainty equivalents for imprecise gambles. ORGANIZATIONAL BEHAVIOR AND HUMAN DECISION PROCESSES 2002. [DOI: 10.1016/s0749-5978(02)00014-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Johnson TR, Schamberger MS, Brown JW, Girod DA. Resolution of acquired pulmonary arteriovenous malformations in a patient with total anomalous systemic venous return. Pediatr Cardiol 2002; 23:210-2. [PMID: 11889537 DOI: 10.1007/s00246-001-0049-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
An 11-year-old male with total anomalous systemic venous return had surgical repair except for the hepatic venous return, which drained to the left atrium. He developed progressive cyanosis and fatigue and was diagnosed with large pulmonary arteriovenous malformations (PAVMs) during cardiac catheterization with the use of bubble contrast echocardiography. After surgical redirection of hepatic venous flow to the right heart and pulmonary arterial system, resolution of these PAVMs was demonstrated clinically and by contrast echocardiography. This unique case report demonstrates the development of PAVMs with exclusion of hepatic venous return through the pulmonary vascular bed while pulsatile pulmonary blood flow remains intact. It reinforces the likelihood of the absence of an as yet unidentified hepatic vasoactive substance as the source for development of PAVMs.
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Matsuguchi T, Musikacharoen T, Johnson TR, Kraft AS, Yoshikai Y. A novel mitogen-activated protein kinase phosphatase is an important negative regulator of lipopolysaccharide-mediated c-Jun N-terminal kinase activation in mouse macrophage cell lines. Mol Cell Biol 2001; 21:6999-7009. [PMID: 11564882 PMCID: PMC99875 DOI: 10.1128/mcb.21.20.6999-7009.2001] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2001] [Accepted: 06/26/2001] [Indexed: 11/20/2022] Open
Abstract
We have isolated a cDNA homologous to known dual-specificity phosphatases from a mouse macrophage cDNA library and termed it MKP-M (for mitogen-activated protein kinase phosphatase isolated from macrophages). Three other presumed splice variant isoforms have also been identified for MKP-M. The longest and most abundant mRNA contains an open reading frame corresponding to 677 amino acids and produces an 80-kDa protein. The deduced amino acid sequence of MKP-M is most similar to those of hVH-5 (or mouse M3/6) and VHP1, a Caenorhabditis elegans tyrosine phosphatase. It includes an N-terminal rhodanase homology domain, the extended active-site sequence motif (V/L)X(V/I)HCXAG(I/V)SRSXT(I/V)XXAY(L/I)M (where X is any amino acid), and a C-terminal PEST sequence. Northern blot analysis revealed a dominant MKP-M mRNA species of approximately 5.5 kb detected ubiquitously among all tissues examined. MKP-M was constitutively expressed in mouse macrophage cell lines, and its expression levels were rapidly increased by lipopolysaccharide (LPS) stimulation but not by tumor necrosis factor alpha (TNF-alpha), gamma interferon, interleukin-2 (IL-2), or IL-15 stimulation. Immunocytochemical analysis showed MKP-M to be present within cytosol. When expressed in COS7 cells, MKP-M blocks activation of mitogen-activated protein kinases with the selectivity c-Jun N-terminal kinase (JNK) >> p38 = extracellular signal-regulated kinase. Furthermore, expression of a catalytically inactive form of MKP-M in a mouse macrophage cell line increased the intensity and duration of JNK activation and TNF-alpha secretion after LPS stimulation, suggesting that MKP-M is at least partially responsible for the desensitization of LPS-mediated JNK activation and cytokine secretion in macrophages.
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Ayres AW, Johnson TR, Hayashi R. Characteristics of fetal heart rate tracings prior to uterine rupture. Int J Gynaecol Obstet 2001; 74:235-40. [PMID: 11543746 DOI: 10.1016/s0020-7292(01)00445-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To identify the fetal heart rate patterns that occurred in a 2-h period of time preceding uterine rupture. METHODS The fetal monitor strips and the medical records of patients with a confirmed diagnosis of uterine rupture were reviewed. These patients delivered at the University of Michigan Hospital from January 1, 1985 to December 31, 1999 and were >or =28 weeks gestational age. Asymptomatic uterine scar dehiscences were excluded. The weeks of gestation, the number of cesarean sections, the surgical findings, and the maternal complications were obtained from the review of the maternal records. The fetal monitor strips for the 2 h preceding the uterine rupture were analyzed, and the fetal heart rate patterns were classified. RESULTS During the study period, there were 11 patients identified with uterine rupture. Seven of the 11 (64%) had operative or post-operative complications. There were no maternal deaths. Review of the eight fetal heart rate tracings available revealed 7/8 (87.5%) with recurrent late decelerations and 4/8 (50%) with terminal bradycardia. All four of the patients with fetal bradycardia were preceded by recurrent late decelerations (100%). CONCLUSIONS The most common fetal heart rate abnormalities that occurred prior to uterine rupture were recurrent late decelerations and bradycardia. The appearance of recurrent late decelerations may be an early sign of impending uterine rupture.
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Schwartz G, Johnson TR, Goetz A, Burris H, Smetzer L, Lampkin T, Sailstad J, Hohneker JA, Von Hoff DD, Rowinsky EK. A phase I and pharmacokinetic study of 1843U89, a noncompetitive inhibitor of thymidylate synthase, in patients with advanced solid malignancies. Clin Cancer Res 2001; 7:1901-11. [PMID: 11448903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
This study was performed to assess the feasibility of administering 1843U89, a potent, noncompetitive inhibitor of thymidylate synthase that does not require polyglutamation for activity, as a 2-min i.v. infusion daily for 5 days every 3 weeks, to determine whether folic acid supplementation ameliorates the toxic effects of 1843U89 and permits further dose escalation, and to recommend doses of 1843U89 administered without and with folic acid for further clinical evaluations. The study also sought to characterize the pharmacokinetic behavior of 1843U89 and to seek preliminary evidence of anticancer activity. Patients with advanced solid malignancies were treated with escalating doses of 1843U89 as a 2-min i.v. infusion daily for 5 days every 3 weeks. Initially, patients were treated in the absence of high-dose folic acid until dose-limiting toxicity was consistently noted. Next, patients were treated with escalating doses of 1843U89 preceded by 1000 mg of folic acid administered p.o. 30 min before each of the 5 daily doses of 1843U89. Patients (32) received 101 total courses of 1843U89 at doses ranging from 1 to 6 mg/m(2)/day with and without folic acid. At the 2 mg/m(2)/day dose level without folic acid, 2 of 7 new patients experienced dose-limiting toxicity, principally neutropenia, mucositis, and malaise in 3 of 11 courses. 1843U89 doses were further increased with folic acid to 6 mg/m(2)/day, but repetitive treatment was not feasible at this dose level because of an unacceptable high incidence of severe neutropenia and mucositis. Other toxicities included thrombocytopenia, rash, and fever. In contrast, repetitive treatment at the 5 mg/m(2)/day dose level was feasible. The pharmacokinetics of 1843U89 were neither dose dependent nor affected by folic acid. On day 1, clearance, terminal half-life, and steady-state volume of distribution values averaged 47.1 +/- 21.7 ml/min/m(2), 7.72 +/- 4.09 h, and 16.7 +/- 8.8 liter/m(2)/h, respectively. The results of the study indicate that the administration of 1843U89 as a 2-min infusion daily for 5 days every 3 weeks without and with folic acid is feasible at 1843U89 doses as high as 2 and 5 mg/m(2)/day, respectively. Because folic acid pretreatment results in no diminution of the antitumor activity of 1843U89 in preclinical studies and ameliorates the toxic effects of 1843U89 in both preclinical models and cancer patients, the therapeutic index of 1843U89 may be enhanced by folic acid pretreatment and, therefore, the development of 1843U89 with folic acid is warranted. However, the question of whether to administer 1843U89 at a dose of 2 mg/m(2)/day with folic acid, which is associated with negligible toxicity, or at its highest feasible dose with folic acid, 5 mg/m(2)/day, should be addressed in appropriately designed trials.
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Mosely DS, Johnson TR, Swann SW. The special operations aviation flight medic. Mil Med 2001; 166:401-4. [PMID: 11370202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2023] Open
Abstract
Medical support in the Army Special Operations Forces is a comprehensive continuum of care that begins at the point of injury and extends through definitive management. Each special operations unit has unique medical needs and, as a result, has developed specially trained medical personnel to fulfill those needs. The 160th Special Operations Aviation Regiment has developed the special operations aviation flight medic to fill this role. The training of these medics involves a systematic, graduated approach with specific milestones to ensure a standardized level of training.
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Abstract
A review of the safety, practicality and cost effectiveness of day surgery anterior cruciate ligament reconstruction was studied in the British set-up. We evaluated 20 patients prospectively who underwent ACL reconstruction as a day surgery procedure for pain control, recovery time, post-operative complications and cost effectiveness. All patients on a verbal response score (VRS) for pain expressed themselves as satisfied or very satisfied. All patients regained a range of movement of 0-90 degrees by 1 week and 0-130 degrees by 6 weeks post-operatively. None of the patients required hospitalisation, only two patients had superficial wound infections at the graft-harvesting site. Cost analysis showed that day surgery ACL reconstruction was cost effective. The average saving per patient was in the range of 20-25% when compared to inpatient ACL reconstruction.
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Johnson TR, Budescu DV, Wallsten TS. Averaging probability judgments: Monte Carlo analyses of asymptotic diagnostic value. JOURNAL OF BEHAVIORAL DECISION MAKING 2001. [DOI: 10.1002/bdm.369] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Johnson TR, Tobias JD. Hypotension following the initiation of tizanidine in a patient treated with an angiotensin converting enzyme inhibitor for chronic hypertension. J Child Neurol 2000; 15:818-9. [PMID: 11198499 DOI: 10.1177/088307380001501211] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Centrally acting alpha-2 adrenergic agonists are one of several pharmacologic agents used in the treatment of spasticity related to disorders of the central nervous system. In addition to their effects on spasticity, certain adverse cardiorespiratory effects have been reported. Adults chronically treated with angiotensin converting enzyme inhibitors may have a limited ability to respond to hypotension when the sympathetic response is simultaneously blocked. The authors present a 10-year-old boy chronically treated with lisinopril, an angiotensin converting enzyme inhibitor, to control hypertension who developed hypotension following the addition of tizanidine, an alpha-2 agonist, for the treatment of spasticity. The possible interaction of tizanidine and other antihypertensive agents should be kept in mind when prescribing therapy to treat either hypertension or spasticity in such patients.
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Pawlowski JE, Nesterov A, Scheinman RI, Johnson TR, Kraft AS. NF-kappa B does not modulate sensitivity of renal carcinoma cells to TNF alpha-related apoptosis-inducing ligand (TRAIL). Anticancer Res 2000; 20:4243-55. [PMID: 11205254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
BACKGROUND Immune cells express TNF-related apoptosis-inducing ligand (TRAIL) and may play an important role in controlling the growth of renal cancer. For this reason we examined the potential cytotoxic and intracellular signaling effects of TRAIL on several renal cancer cell (RCC) lines. METHODS Cytotoxicity was determined using an MTS tetrazolium based assay. Death receptor expression was measured by reverse-transcription polymerase chain reaction. Immunoblot analysis was used to measure cFLIP, caspase-8 and phosphorylated JNK and p38. Activation of NF-kappa B was determined by electrophoretic mobility shift assays. RESULTS Two RCC lines were highly sensitive to TRAIL-induced cell death, two were of intermediate sensitivity, and two were insensitive. Sensitivity to TRAIL-stimulated apoptosis did not correlate with expression of death receptors, decoy receptors, or expression of the caspase-8-inhibitory protein cFLIP. Neither activation or inhibition of the NF-kappa B signal transduction pathway protected sensitive cells from TRAIL-induced cell death. CONCLUSIONS NF-kappa B, although stimulated in these cell lines, does not play a role in the sensitivity of RCC to TRAIL and could play other functions in TRAIL signaling.
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Barr FE, Pedigo H, Johnson TR, Shepherd VL. Surfactant protein-A enhances uptake of respiratory syncytial virus by monocytes and U937 macrophages. Am J Respir Cell Mol Biol 2000; 23:586-92. [PMID: 11062136 DOI: 10.1165/ajrcmb.23.5.3771] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Surfactant protein (SP)-A is a known opsonin for a variety of pulmonary pathogens. SP-A enhances ingestion of these pathogens by interaction with an SP-A receptor (SP-AR) found on phagocytic cells such as peripheral blood monocytes (PBMC) and alveolar macrophages. Respiratory syncytial virus (RSV) is the most important respiratory pathogen in children. Recent studies have indicated that SP-A levels may be decreased in RSV bronchiolitis and pneumonia. In this study we examined the role of SP-A in uptake of RSV by both PBMC and U937 macrophages, a human macrophage cell line known to express SP-ARs. In addition, we studied the effect of SP-A- mediated uptake of RSV on production of tumor necrosis factor (TNF)-alpha and interleukin (IL)-10 by these cells because incomplete immunity to recurrent RSV infection has been partially attributed to abnormal cytokine responses by macrophages. SP-A enhanced binding and uptake of fluorescently labeled RSV (RSV-FITC) by PBMC in a dose-dependent manner, with a maximal effect seen with 10 to 15 microg/ml SP-A as measured by both percent fluorescent monocytes and linear mean fluorescence (lmf) of individual cells. SP-A also enhanced uptake of RSV-FITC by U937 macrophages, with a maximal effect seen with 20 microg/ml SP-A as measured by both percent fluorescent monocytes and lmf. With respect to TNF-alpha levels, RSV alone slightly enhanced TNF-alpha production by PBMC and decreased TNF-alpha production by U937 macrophages measured at 12 h after addition of RSV. SP-A-mediated uptake of RSV significantly enhanced TNF-alpha production by PBMC and reversed the RSV-induced depression of TNF-alpha by U937 macrophages. RSV significantly enhanced IL-10 production by both cell types, which was reversed by SP-A-mediated uptake. These findings suggest that SP-A is an important opsonin for RSV and that SP-A-mediated uptake of RSV may alter some of the unusual cytokine responses that are postulated to be involved in incomplete immunity to recurrent infection.
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Johnson TR, Biggs JR, Winbourn SE, Kraft AS. Regulation of dual-specificity phosphatases M3/6 and hVH5 by phorbol esters. Analysis of a delta-like domain. J Biol Chem 2000; 275:31755-62. [PMID: 10915787 DOI: 10.1074/jbc.m004182200] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Treatment of leukemic cells with phorbol 12-myristate 13-acetate (PMA) induces a short-lived phosphorylation and activation of stress-activated protein kinase (SAPK) and cellular differentiation. To investigate whether the rapid deactivation of SAPK results from dephosphorylation by dual-specificity phosphatases (DSPs), we studied regulation of the DSP hVH5 and its murine orthologue M3/6 in K562 human leukemia cells. PMA treatment rapidly induced hVH5 transcripts in these cells, and induced expression of M3/6 completely inhibited PMA-stimulated phosphorylation of SAPK, suggesting a feedback loop to control SAPK activity. Using both stable cell lines and transient transfection we demonstrate that activation of SAPK rapidly stimulated phosphorylation of M3/6. This phosphorylation did not regulate the half-life of total cellular M3/6. hVH5 and M3/6 shares with all sequenced mammalian DSPs an amino acid motif, XILPXLXL, located approximately 80 amino acids from the active site. The hVH5-M3/6 sequence, RILPHLYL, shares significant homology with the SAPK binding site of the c-Jun protein, called the delta domain. This motif was found to be important for DSP function, because deletion of RILPHLYL inhibits SAPK-mediated phosphorylation of M3/6, and deletion of this sequence or mutation of the LYL portion blocks the ability of this phosphatase to dephosphorylate SAPK.
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Fischer JE, Johnson JE, Johnson TR, Graham BS. Pertussis toxin sensitization alters the pathogenesis of subsequent respiratory syncytial virus infection. J Infect Dis 2000; 182:1029-38. [PMID: 10979896 DOI: 10.1086/315806] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2000] [Revised: 05/26/2000] [Indexed: 11/03/2022] Open
Abstract
Evidence suggests that both host and viral factors influence disease severity after infection with respiratory syncytial virus (RSV). To characterize the effects of pertussis toxin (PT) sensitization on subsequent RSV infection, BALB/c mice were treated with PT parenterally before RSV challenge. Priming with purified and detoxified PT before RSV challenge increased postchallenge weight loss and mortality. PT priming changed the kinetics, location, and composition of the cellular infiltrate in the lung but altered neither antibody responses nor virus titers. Passive transfer of PT-sensitized splenocytes produced similar responses. Priming with purified, but not genetically detoxified, PT propagated a modest type 2 cytokine response to RSV antigens. However, anti-interleukin-4 treatment before RSV challenge failed to abrogate the effects of PT priming. These data confirm that the preexisting immune environment can change virus-specific immunity and provide both a model for study of RSV disease and evidence that noninfectious immunomodulators may impact pathogen-specific immunity.
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Rowinsky EK, Johnson TR, Geyer CE, Hammond LA, Eckhardt SG, Drengler R, Smetzer L, Coyle J, Rizzo J, Schwartz G, Tolcher A, Von Hoff DD, De Jager RL. DX-8951f, a hexacyclic camptothecin analog, on a daily-times-five schedule: a phase I and pharmacokinetic study in patients with advanced solid malignancies. J Clin Oncol 2000; 18:3151-63. [PMID: 10963644 DOI: 10.1200/jco.2000.18.17.3151] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE To assess the feasibility of administering DX-8951f (exatecan mesylate), a water-soluble, camptothecin analog, as a 30-minute intravenous infusion daily for 5 days every 3 weeks, determine the maximum-tolerated dose (MTD) and pharmacokinetic (PK) behavior of DX-8951f, and seek preliminary evidence of anticancer activity. PATIENTS AND METHODS Patients with advanced solid malignancies were treated with escalating doses of DX-8951f. After three patients were treated at the first dose level, doses were to be escalated in increments of 100%, using a single patient at each dose level unless moderate toxicity was observed. The MTD, defined as the highest dose level at which the incidence of dose-limiting toxicity did not exceed 20%, was calculated separately for minimally pretreated (MP) and heavily pretreated (HP) patients. The PK and excretory profiles of DX-8951, the anhydrous form of DX-8951f, were also characterized. RESULTS Thirty-six patients were treated with 130 courses of DX-8951f at six dose levels ranging from 0.1 to 0.6 mg/m(2)/d. Brief, noncumulative neutropenia was the most common toxicity observed. Severe myelosuppression (neutropenia that was protracted and/or associated with fever and/or severe thrombocytopenia) was consistently experienced by HP and MP patients at doses exceeding 0.3 and 0.5 mg/m(2)/d, respectively. Nonhematologic toxicities (nausea, vomiting, and diarrhea) were also observed, but these effects were rarely severe. Objective antitumor activity included partial responses in one patient each with platinum-resistant extrapulmonary small-cell and fluoropyrimidine- and irinotecan-resistant colorectal carcinoma, and minor responses in patients with prostate, hepatocellular, thymic, primary peritoneal, and irinotecan-resistant colorectal carcinomas. The PKs of total DX-8951 were linear and well fit by a three-compartment model. CONCLUSION The recommended doses for phase II studies of DX-8951f as a 30-minute infusion daily for 5 days every 3 weeks are 0.5 and 0.3 mg/m(2)/d for MP and HP patients, respectively. The characteristics of the myelosuppressive effects of DX-8951f, paucity of severe nonhematologic toxicities, and antitumor activity against a wide range of malignancies warrant broad disease-directed evaluations of DX-8951f on this schedule.
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