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Padia SA, Johnson GE, Horton KJ, Kwan S, Vaidya S, Ingraham CR, Monsky WL, Valji K, Kogut MJ, Yeung RS, Park JO, Bhattacharya R, Liou I, Harris WP. Segmental yttrium-90 radioembolization versus chemoembolization for localized hepatocellular carcinoma. J Clin Oncol 2016. [DOI: 10.1200/jco.2016.34.15_suppl.4084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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McKay T, Ingraham CR, Johnson GE, Kogut MJ, Vaidya S, Padia SA. Cone-Beam CT with Fluoroscopic Overlay Versus Conventional CT Guidance for Percutaneous Abdominopelvic Abscess Drain Placement. J Vasc Interv Radiol 2015; 27:52-7. [PMID: 26573489 DOI: 10.1016/j.jvir.2015.09.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Revised: 09/19/2015] [Accepted: 09/19/2015] [Indexed: 10/22/2022] Open
Abstract
PURPOSE To compare technical success and procedure time for percutaneous abscess drain placement with fluoroscopic cone-beam computed tomography (CT) and two-axis needle guidance versus conventional CT guidance. MATERIALS AND METHODS A total of 85 consecutive patients undergoing abdominopelvic abscess drain placement guided by fluoroscopic cone-beam CT or conventional CT were retrospectively reviewed over a 2-year period. Forty-three patients underwent drain placement with cone-beam CT using XperGuide navigation and 42 underwent placement with conventional 64-slice CT. Patient characteristics, median abscess size (6.8 cm vs 7.8 cm; P = .14), and depth to abscess (7.2 cm vs 7.7 cm; P = .88) were similar between groups. RESULTS Technical success rates were 98% (42 of 43) in the cone-beam CT group and 100% (42 of 42) in the conventional CT group (P = .32), with a 10-F pigtail drainage catheter inserted in the majority of cases. There were no complications in either group. There was no significant difference in effective dose between groups (9.6 mSv vs 10.7 mSv; P = .30). Procedure times were significantly shorter in the cone-beam CT group (43 min vs 62 min; P = .02). In addition, during the study period, there was a gradual improvement in procedure time in the cone-beam CT group (50% reduction), whereas procedure time did not change for the conventional CT group. CONCLUSIONS Cone-beam CT guidance appears to be equivalent to conventional CT guidance for drain placement into medium-sized abdominopelvic collections, yielding similar technical success rates and radiation doses, with the additional benefit of reduced procedure times.
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Padia SA, Johnson GE, Yeung RS, Park JO, Hippe DS, Kogut MJ. Irreversible Electroporation in Patients with Hepatocellular Carcinoma: Immediate versus Delayed Findings at MR Imaging. Radiology 2015; 278:285-94. [PMID: 26523493 DOI: 10.1148/radiol.2015150031] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
PURPOSE To assess the postprocedure findings of irreversible electroporation (IRE) in patients with hepatocellular carcinoma (HCC) at magnetic resonance (MR) imaging. MATERIALS AND METHODS This retrospective study was Institutional Review Board approved, and informed consent was waived. Twenty patients with HCC were treated with IRE over a 2.5-year period. The median patient age was 62 years, and 75% of patients had cirrhosis with a Child-Pugh score of A. The median tumor diameter was 2.0 cm (range, 1.0-3.3 cm). Contrast material-enhanced multiphase MR imaging was performed on postprocedure days 1 and 30 and every 90 days thereafter. Ablation zone sizes and signal intensities were compared between each time point for both T1- and T2-weighted images. Trends in signal intensity and tumor dimensions over time were quantified by using generalized linear models. RESULTS MR imaging appearances of treated tumors include a zone of peripheral enhancement with centripetal filling on delayed contrast-enhanced images. Compared with postprocedure day 1, every 90 days there is a decrease of 28.9% (mean, axis) in the size of the enhancing ablation zone. Over time, there is a trend toward decreasing signal intensity in the peripheral ablation zone on both T2-weighted (P = .01) and contrast-enhanced T1-weighted (P < .08) images. Conversely, the tumor itself typically has increased signal intensity on the same sequences. CONCLUSION IRE of HCC results in a large region of enhancement on immediate postprocedure MR images that, over time, involutes and is associated with decreasing signal intensity of the peripheral ablation zone. This phenomenon may represent resolution of the reversible penumbra.
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Kogut MJ, Shin DS, Padia SA, Johnson GE, Hippe DS, Valji K. Intra-Arterial Thrombolysis for Hepatic Artery Thrombosis following Liver Transplantation. J Vasc Interv Radiol 2015; 26:1317-22. [PMID: 26190188 DOI: 10.1016/j.jvir.2015.06.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 06/01/2015] [Accepted: 06/02/2015] [Indexed: 12/13/2022] Open
Abstract
PURPOSE Hepatic artery thrombosis (HAT) is a major cause of morbidity and death following liver transplantation. The purpose of this study was to evaluate the safety and efficacy of intra-arterial thrombolysis (IAT) in liver transplant recipients with HAT. MATERIALS AND METHODS Adult liver transplant recipients who underwent attempted IAT for HAT were identified. This included patients with early and late HAT (occurring less than or greater than 30 d after transplantation). Records were reviewed to determine the rates of technical success, complications, surgical revascularization, repeat liver transplantation, and ischemic cholangiopathy. RESULTS Twenty-six patients underwent attempted thrombolysis, 13 of whom had early HAT. IAT was successfully initiated in 23 patients (88%), with a median IAT duration of 28 hours (range, 12-90 h). Recanalization was achieved in 12 patients (46%). Major complications were observed in 11 patients (42%). The early HAT group showed a trend toward increased major bleeding compared with the late HAT group (50% vs 9%; P = .07). Among 12 patients who had technically successful thrombolysis, five (42%) required surgical revascularization or repeat transplantation within 2 months. At 6 months after thrombolysis, 45% with unsuccessful recanalization avoided surgery or development of ischemic cholangiopathy, similar to the proportion in those who had successful recanalization (42%; P = .88). CONCLUSIONS Posttransplantation hepatic artery thrombolysis yields suboptimal results with a high complication rate, especially in early HAT. Even with successful restoration of flow, clinical outcomes are poor. Although thrombolysis may still be considered in view of the limited treatment options for HAT, awareness of potential complications and suboptimal success rate is essential.
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Johnson GE, Soeteman-Hernández LG, Gollapudi BB, Bodger OG, Dearfield KL, Heflich RH, Hixon JG, Lovell DP, MacGregor JT, Pottenger LH, Thompson CM, Abraham L, Thybaud V, Tanir JY, Zeiger E, van Benthem J, White PA. Derivation of point of departure (PoD) estimates in genetic toxicology studies and their potential applications in risk assessment. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2014; 55:609-23. [PMID: 24801602 PMCID: PMC6710644 DOI: 10.1002/em.21870] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/07/2014] [Accepted: 04/11/2014] [Indexed: 05/13/2023]
Abstract
Genetic toxicology data have traditionally been employed for qualitative, rather than quantitative evaluations of hazard. As a continuation of our earlier report that analyzed ethyl methanesulfonate (EMS) and methyl methanesulfonate (MMS) dose-response data (Gollapudi et al., 2013), here we present analyses of 1-ethyl-1-nitrosourea (ENU) and 1-methyl-1-nitrosourea (MNU) dose-response data and additional approaches for the determination of genetic toxicity point-of-departure (PoD) metrics. We previously described methods to determine the no-observed-genotoxic-effect-level (NOGEL), the breakpoint-dose (BPD; previously named Td), and the benchmark dose (BMD10 ) for genetic toxicity endpoints. In this study we employed those methods, along with a new approach, to determine the non-linear slope-transition-dose (STD), and alternative methods to determine the BPD and BMD, for the analyses of nine ENU and 22 MNU datasets across a range of in vitro and in vivo endpoints. The NOGEL, BMDL10 and BMDL1SD PoD metrics could be readily calculated for most gene mutation and chromosomal damage studies; however, BPDs and STDs could not always be derived due to data limitations and constraints of the underlying statistical methods. The BMDL10 values were often lower than the other PoDs, and the distribution of BMDL10 values produced the lowest median PoD. Our observations indicate that, among the methods investigated in this study, the BMD approach is the preferred PoD for quantitatively describing genetic toxicology data. Once genetic toxicology PoDs are calculated via this approach, they can be used to derive reference doses and margin of exposure values that may be useful for evaluating human risk and regulatory decision making.
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Johnson GE, Sandstrom CK, Kogut MJ, Ingraham CR, Stratil PG, Valji K, Vo NJ, Glickerman D, Hippe DS, Padia SA. Frequency of external iliac artery branch injury in blunt trauma: improved detection with selective external iliac angiography. J Vasc Interv Radiol 2013; 24:363-9. [PMID: 23433412 DOI: 10.1016/j.jvir.2012.12.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 12/06/2012] [Accepted: 12/06/2012] [Indexed: 01/21/2023] Open
Abstract
PURPOSE To assess the utility of selective external iliac artery (EIA) angiography and the frequency of injury to branches of the EIA in cases of blunt pelvic trauma. MATERIALS AND METHODS A retrospective review of pelvic angiograms in 66 patients with blunt pelvic trauma was conducted over a 12-month period. Pelvic and femur fracture patterns were correlated to the presence of EIA injury. Pelvic arteriography was compared versus selective EIA angiography for the detection of arterial injury. RESULTS Fifty-four of 66 patients (82%) exhibited pelvic arterial injury or elicited enough suspicion for injury to warrant embolization. Internal iliac artery embolization was performed in 50 of 66 (76%). EIA branch injury was identified in 11 of 66 patients (17%), and 10 were successfully embolized. EIA branch vessel injury was identified more frequently when there was ipsilateral intertrochanteric fracture (P = .07) or ipsilateral ilium fracture (P = .07). The sensitivity of nonselective pelvic angiography in the detection of EIA branch vessel injury was 45%. CONCLUSIONS EIA branch injury occurs in a substantial fraction of patients with blunt pelvic trauma who undergo pelvic angiography. Selective EIA angiography should be considered in all patients undergoing pelvic angiography in this situation.
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Zaïr ZM, Johnson GE, Griffiths AP, Jenkins GJ. Diagnostic correlation between the expression of the DNA repair enzyme N-methylpurine DNA glycosylase and esophageal adenocarcinoma onset: a retrospective pilot study. Dis Esophagus 2013; 26:644-50. [PMID: 23137018 DOI: 10.1111/dote.12003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
EAC in its early stages, when it can potentially be cured, is rarely symptomatic and is associated with high mortality rates because in part of late-stage diagnosis. Given that DNA repair is an important contributory factor of early-stage malignancy, our study focused on the expression of the base excision repair enzyme N-methylpurine DNA glycosylase (MPG) in EAC disease onset. MPG messenger RNA (mRNA) expression levels were determined using quantitative reverse transcriptase polymerase chain reaction from a maximum of 72 patient samples. Immunohistochemistry was further utilized for the detection of MPG protein, and semiquantitative analysis performed using an H-score approach was carried out on a total of 130 archival tissue samples of different esophageal pathologies. Nuclear localized MPG protein was detected in all nonmalignant tissues derived from the enterohepatic system, with H-score values of 3.9-5.5 ± 0.4-1.0. In cancerous tissues derived from the enterohepatic system, a 9.5-fold increase in the level of MPG mRNA expression was specifically observed in the malignant regions located within the esophagus region. Further analysis revealed a 9- and 14-fold increase in MPG mRNA expression in EAC tumor, node, metastasis stages II and III, respectively, suggesting MPG expression to correlate with EAC disease progression. Immunohistochemistry analysis further showed a sevenfold significant increase in MPG protein expression in EAC tissues. Intriguingly, there was a fivefold significant decrease in nuclear localized MPG protein expression in tissues derived from Barrett's esophagus and low-grade dysplasia. Such findings highlight a complex regulatory pattern governing DNA glycosylase base excision repair initiation, as normal tissue undergoes Barrett's metaplasia and later dedifferentiates to EAC. Indeed, disease-stage-specific alterations in the expression of MPG may highlight a potential role for MPG in determining EAC onset and thus potentially be of clinical relevance for early disease detection and increased patient survival.
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Borthwick LA, Corris PA, Mahida R, Walker A, Gardner A, Suwara M, Johnson GE, Moisey EJ, Brodlie M, Ward C, Perry JD, De Soyza A, Mann DA, Fisher AJ. TNFα from classically activated macrophages accentuates epithelial to mesenchymal transition in obliterative bronchiolitis. Am J Transplant 2013; 13:621-33. [PMID: 23331923 DOI: 10.1111/ajt.12065] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Revised: 10/04/2012] [Accepted: 10/08/2012] [Indexed: 01/25/2023]
Abstract
Bronchiolitis obliterans syndrome is characterized by fibrotic obliteration of small airways which severely impairs graft function and survival after lung transplantation. Bronchial epithelial cells from the transplanted lung can undergo epithelial to mesenchymal transition and this can be accentuated by activated macrophages. Macrophages demonstrate significant plasticity and change phenotype in response to their microenvironment. In this study we aimed to identify secretory products from macrophages that might be therapeutic targets for limiting the inflammatory accentuation of epithelial to mesenchymal transition in bronchiolitis obliterans syndrome. TNFα, IL-1β and IL-8 are elevated in bronchoalveolar lavage from lung transplant patients prior to diagnosis of bronchiolitis obliterans syndrome. Classically activated macrophages secrete more TNFα and IL-1β than alternatively activated macrophages and dramatically accentuate TGF-β1-driven epithelial to mesenchymal transition in bronchial epithelial cells isolated from lung transplant patients. Blocking TNFα, but not IL-1β, inhibits the accentuation of epithelial to mesenchymal transition. In a pilot unblinded therapeutic intervention in five patients with progressive bronchiolitis obliterans syndrome, anti-TNFα treatment improved forced expiratory volume in 1 second and 6-min walk distances in four patients. Our data identify TNFα as a potential new therapeutic target in bronchiolitis obliterans syndrome deserving of a randomized placebo controlled clinical trial.
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Gollapudi BB, Johnson GE, Hernandez LG, Pottenger LH, Dearfield KL, Jeffrey AM, Julien E, Kim JH, Lovell DP, Macgregor JT, Moore MM, van Benthem J, White PA, Zeiger E, Thybaud V. Quantitative approaches for assessing dose-response relationships in genetic toxicology studies. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2013; 54:8-18. [PMID: 22987251 DOI: 10.1002/em.21727] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Revised: 07/19/2012] [Accepted: 07/23/2012] [Indexed: 06/01/2023]
Abstract
Genetic toxicology studies are required for the safety assessment of chemicals. Data from these studies have historically been interpreted in a qualitative, dichotomous "yes" or "no" manner without analysis of dose-response relationships. This article is based upon the work of an international multi-sector group that examined how quantitative dose-response relationships for in vitro and in vivo genetic toxicology data might be used to improve human risk assessment. The group examined three quantitative approaches for analyzing dose-response curves and deriving point-of-departure (POD) metrics (i.e., the no-observed-genotoxic-effect-level (NOGEL), the threshold effect level (Td), and the benchmark dose (BMD)), using data for the induction of micronuclei and gene mutations by methyl methanesulfonate or ethyl methanesulfonate in vitro and in vivo. These results suggest that the POD descriptors obtained using the different approaches are within the same order of magnitude, with more variability observed for the in vivo assays. The different approaches were found to be complementary as each has advantages and limitations. The results further indicate that the lower confidence limit of a benchmark response rate of 10% (BMDL(10) ) could be considered a satisfactory POD when analyzing genotoxicity data using the BMD approach. The models described permit the identification of POD values that could be combined with mode of action analysis to determine whether exposure(s) below a particular level constitutes a significant human risk. Subsequent analyses will expand the number of substances and endpoints investigated, and continue to evaluate the utility of quantitative approaches for analysis of genetic toxicity dose-response data.
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Johnson GE, Ingraham CR, Nair AV, Padia SA. Hepatic abscess complicating transarterial chemoembolization in a patient with liver metastases. Semin Intervent Radiol 2012; 28:193-7. [PMID: 22654261 DOI: 10.1055/s-0031-1280663] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Hepatic abscess following transarterial chemoembolization is an uncommon complication. The authors describe a case of liver abscess after transarterial chemoembolization for neuroendocrine liver metastases, including risk factors, prophylaxis, treatment, and outcomes.
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Brodlie M, McKean MC, Johnson GE, Anderson AE, Hilkens CMU, Fisher AJ, Corris PA, Lordan JL, Ward C. Raised interleukin-17 is immunolocalised to neutrophils in cystic fibrosis lung disease. Eur Respir J 2011; 37:1378-85. [PMID: 21109552 DOI: 10.1183/09031936.00067110] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Interleukin (IL)-17 is pivotal in orchestrating the activity of neutrophils. Neutrophilic inflammation is the dominant pathology in cystic fibrosis (CF) lung disease. We investigated IL-17 protein expression in the lower airway in CF, its cellular immunolocalisation and the effects of IL-17 on CF primary bronchial epithelial cells. Immunohistochemistry was performed on explanted CF lungs and compared with the non-suppurative condition pulmonary hypertension (PH). Airway lavages and epithelial cultures were generated from explanted CF lungs. Immunoreactivity for IL-17 was significantly increased in the lower airway epithelium in CF (median 14.1%) compared with PH (2.95%, p=0.0001). The number of cells staining positive for IL-17 in the lower airway mucosa was also increased (64 cells·mm(-1) compared with 9 cells·mm(-1) basement membrane, p=0.0005) and included both neutrophils in addition to mononuclear cells. IL-17 was detectable in airway lavages from explanted CF lungs. Treatment of epithelial cultures with IL-17 increased production of IL-8, IL-6 and granulocyte macrophage colony-stimulating factor. In conclusion, immunoreactive IL-17 is raised in the lower airway of people with CF and localises to both neutrophils and mononuclear cells. IL-17 increases production of pro-neutrophilic mediators by CF epithelial cells, suggesting potential for a positive feedback element in airway inflammation.
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Borthwick LA, McIlroy EI, Gorowiec MR, Brodlie M, Johnson GE, Ward C, Lordan JL, Corris PA, Kirby JA, Fisher AJ. Inflammation and epithelial to mesenchymal transition in lung transplant recipients: role in dysregulated epithelial wound repair. Am J Transplant 2010; 10:498-509. [PMID: 20055810 DOI: 10.1111/j.1600-6143.2009.02953.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Epithelial to mesenchymal transition (EMT) has been implicated in the pathogenesis of obliterative bronchiolitis (OB) after lung transplant. Although TNF-alpha accentuates TGF-beta1 driven EMT in primary human bronchial epithelial cells (PBECs), we hypothesized that other acute pro-inflammatory cytokines elevated in the airways of patients with OB may also accentuate EMT and contribute to dysregulated epithelial wound repair. PBECs from lung transplant recipients were stimulated with TGF-beta1+/-IL-1beta, IL-8, TNF-alpha or activated macrophages in co-culture and EMT assessed. The quality and rate of wound closure in a standardized model of lung epithelial injury was assessed in response to above stimuli. Co-treatment with TGF-beta1+TNF-alpha or IL-1beta significantly accentuates phenotypic and some functional features of EMT compared to TGF-beta1 alone. Co-treatment with TGF-beta1+TNF-alpha or IL-1beta accelerates epithelial wound closure however the quality of repair is highly dysregulated. Co-treatment with TGF-beta1+IL-8 has no significant effect on EMT or the speed or quality of wound healing. Activated macrophages dramatically accentuate TGF-beta1-driven EMT and cause dysregulated wound repair. Crosstalk between macrophage-derived acute inflammation in the airway and elevated TGF-beta1 may favor dysregulated airway epithelial repair and fibrosis in the lung allograft via EMT.
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Borthwick LA, Parker SM, Brougham KA, Johnson GE, Gorowiec MR, Ward C, Lordan JL, Corris PA, Kirby JA, Fisher AJ. Epithelial to mesenchymal transition (EMT) and airway remodelling after human lung transplantation. Thorax 2009; 64:770-7. [PMID: 19213777 DOI: 10.1136/thx.2008.104133] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND Aberrant epithelial repair is a key event in the airway remodelling which characterises obliterative bronchiolitis (OB) in the transplanted lung. The potential for airway epithelium from lung transplant recipients to undergo epithelial to mesenchymal cell transition (EMT) was assessed in culture and in vivo in lung allograft tissue. METHODS Change in epithelial and mesenchymal marker expression was assessed after stimulation with transforming growth factor beta(1) (TGF-beta(1)) alone or in combination with tumour necrosis factor alpha (TNFalpha) and compared with untreated controls. The ability of cells to deposit extracellular matrix, secrete matrix metalloproteinases (MMPs) and invade collagen was investigated. Immunolocalisation of epithelial and mesenchymal markers was compared in airway tissue from stable recipients and those with OB. RESULTS Untreated cells maintained epithelial morphology and phenotype. TGF-beta(1) reduced expression of epithelial markers, increased expression of vimentin and fibronectin, promoted collagen I and fibronectin deposition and increased MMP-9 production. Co-treatment with TNFalpha dramatically accentuated phenotypic and some functional features of EMT. Airway epithelial biopsies from recipients with OB demonstrated significantly increased staining for mesenchymal markers and significantly reduced E-cadherin staining compared with stable recipients. CONCLUSIONS These observations demonstrate the ability of human airway epithelium to undergo EMT and suggest this phenomenon may be a potential link between inflammatory injury and TGF-beta(1)-driven airway remodelling in the development of OB.
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Johnson GE. Epidemiological Features of a Typhoid Fever Outbreak in West Philadelphia Following a Supper. Am J Public Health Nations Health 2008; 26:913-7. [PMID: 18014502 DOI: 10.2105/ajph.26.9.913] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Barber RC, Hickenbotham P, Hatch T, Kelly D, Topchiy N, Almeida GM, Jones GDD, Johnson GE, Parry JM, Rothkamm K, Dubrova YE. Radiation-induced transgenerational alterations in genome stability and DNA damage. Oncogene 2006; 25:7336-42. [PMID: 16751800 DOI: 10.1038/sj.onc.1209723] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Mutation induction in directly exposed cells is currently regarded as the main component of the genetic risk of ionizing radiation for humans. However, recent data on the transgenerational increases in mutation rates in the offspring of irradiated parents indicate that the genetic risk could be greater than predicted previously. Here, we have analysed transgenerational changes in mutation rates and DNA damage in the germline and somatic tissues of non-exposed first-generation offspring of irradiated inbred male CBA/Ca and BALB/c mice. Mutation rates at an expanded simple tandem repeat DNA locus and a protein-coding gene (hprt) were significantly elevated in both the germline (sperm) and somatic tissues of all the offspring of irradiated males. The transgenerational changes in mutation rates were attributed to the presence of a persistent subset of endogenous DNA lesions (double- and single-strand breaks), measured by the phosphorylated form of histone H2AX (gamma-H2AX) and alkaline Comet assays. Such remarkable transgenerational destabilization of the F(1) genome may have important implications for cancer aetiology and genetic risk estimates. Our data also provide important clues on the still unknown mechanisms of radiation-induced genomic instability.
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Forrest IA, Murphy DM, Ward C, Jones D, Johnson GE, Archer L, Gould FK, Cawston TE, Lordan JL, Corris PA. Primary airway epithelial cell culture from lung transplant recipients. Eur Respir J 2006; 26:1080-5. [PMID: 16319339 DOI: 10.1183/09031936.05.00141404] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Long-term survival in lung transplantation is limited by the development of obliterative bronchiolitis, a condition characterised by inflammation, epithelial injury, fibroproliferation and obliteration of bronchioles leading to airflow obstruction. To investigate the role of the bronchial epithelium in the pathogenesis of obliterative bronchiolitis the current study aimed to establish primary bronchial epithelial cell cultures (PBEC) from lung allografts. Four to six bronchial brushings were obtained from sub-segmental bronchi of lung allografts. Cells were seeded onto collagen-coated plates and grown to confluence in bronchial epithelial growth medium. Bronchial brushings (n=33) were obtained from 27 patients. PBECs were grown to confluence from 12 out of 33 (39%) brushings. Failure to reach confluence was due to early innate infection. Bacteria were usually isolated from both bronchoalveolar lavage and culture media, but a separate population was identified in culture media only. Primary culture of bronchial epithelial cells from lung transplant recipients is feasible, despite a high rate of early, patient-derived infection. Latent infection of the allograft, identified only by bronchial brushings, may itself be a persistent stimulus for epithelial injury. This technique facilitates future mechanistic studies of airway epithelial responses in the pathogenesis of obliterative bronchiolitis.
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Jenkins GJS, Doak SH, Johnson GE, Quick E, Waters EM, Parry JM. Do dose response thresholds exist for genotoxic alkylating agents? Mutagenesis 2005; 20:389-98. [PMID: 16135536 DOI: 10.1093/mutage/gei054] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The demonstration and acceptance of dose response thresholds for genotoxins may have substantial implications for the setting of safe exposure levels. Here we test the hypothesis that direct-acting DNA reactive agents may exhibit thresholded dose responses. We examine the potential mechanisms involved in such thresholded responses, particularly in relation to those of alkylating agents. As alkylating agents are representative model DNA reactive compounds with well characterized activities and DNA targets, they could help shed light on the general mechanisms involved in thresholded dose responses for genotoxins. Presently, thresholds have mainly been described for agents with non-DNA targets. We pay particular attention here to the contribution of DNA repair to genotoxic thresholds. A review of the literature shows that limited threshold data for alkylating agents are currently available, but the contribution of DNA repair in thresholded dose responses is suggested by several studies. The existence of genotoxic thresholds for alkylating agents methylmethanesulfonate is also supported here by data from our laboratory. Overall, it is clear that different endpoints induced by the same alkylator, can possess different dose response characteristics. This may have an impact on the setting of safe exposure levels for such agents. The limited information available concerning the dose response relationships of alkylators can nevertheless lead to the design of experiments to investigate the mechanisms that may be involved in threshold responses. Through using paired alkylators inducing different lesions, repaired by different pathways, insights into the processes involved in genotoxic thresholds may be elucidated. Furthermore, as alkyl-guanine-DNA transferase, base excision repair and mismatch repair appear to contribute to genotoxic thresholds for alkylators, cells deficient in these repair processes may possess altered dose responses compared with wild-type cells and this approach may help understand the contribution of these repair pathways to the production of thresholds for genotoxic effects in general. Finally, genotoxic thresholds are currently being described for acute exposures to single agents in vitro, however, dose response data for chronic exposures to complex mixtures are, as yet, a long way off.
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Ward C, Forrest IA, Brownlee IA, Johnson GE, Murphy DM, Pearson JP, Dark JH, Corris PA. Pepsin like activity in bronchoalveolar lavage fluid is suggestive of gastric aspiration in lung allografts. Thorax 2005; 60:872-4. [PMID: 16055614 PMCID: PMC1747219 DOI: 10.1136/thx.2004.036426] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND A biologically plausible link between gastro-oesophageal reflux (GOR), aspiration, and lung allograft dysfunction has been suggested, but there is no systematic evidence indicating the presence of gastric contents in the lung. We have tested the hypothesis that pepsin, as a marker of aspiration, is detectable in bronchoalveolar lavage (BAL) fluid of allograft recipients who had not reported symptoms of GOR. METHODS Standardised 3 x 60 ml surveillance BAL fluid samples from 13 chronologically sequential stable lung allograft recipients without chronic rejection (10 patients treated with a prophylactic proton pump inhibitor) were studied. Lavage supernatants were assayed by an ELISA based on a monospecific goat antibody for pepsin/pepsinogen. Pepsin levels were compared with those from four normal volunteer controls. RESULTS Pepsin levels were measurable in all allograft recipients, in keeping with gastric aspiration (median 109 ng/ml (range 35-1375)). In the control group the pepsin levels were below the limit of detection. Treatment with a proton pump inhibitor was not correlated with pepsin levels. There was no correlation between BAL fluid neutrophils and pepsin levels. CONCLUSION These data demonstrate lung epithelial lining fluid concentrations of pepsin in lung allograft recipients which are much higher than blood reference levels, with no detectable pepsin in controls. This provides direct evidence of gastric aspiration, which is potentially injurious to the allograft.
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Ward C, Forrest IA, Brownlee IA, Johnson GE, Murphy DM, Pearson JP, Dark JH, Corris PA. Pepsin like activity in bronchoalveolar lavage fluid is suggestive of gastric aspiration in lung allografts. Thorax 2005. [PMID: 16055614 DOI: 10.1163/thx.2004.036426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND A biologically plausible link between gastro-oesophageal reflux (GOR), aspiration, and lung allograft dysfunction has been suggested, but there is no systematic evidence indicating the presence of gastric contents in the lung. We have tested the hypothesis that pepsin, as a marker of aspiration, is detectable in bronchoalveolar lavage (BAL) fluid of allograft recipients who had not reported symptoms of GOR. METHODS Standardised 3 x 60 ml surveillance BAL fluid samples from 13 chronologically sequential stable lung allograft recipients without chronic rejection (10 patients treated with a prophylactic proton pump inhibitor) were studied. Lavage supernatants were assayed by an ELISA based on a monospecific goat antibody for pepsin/pepsinogen. Pepsin levels were compared with those from four normal volunteer controls. RESULTS Pepsin levels were measurable in all allograft recipients, in keeping with gastric aspiration (median 109 ng/ml (range 35-1375)). In the control group the pepsin levels were below the limit of detection. Treatment with a proton pump inhibitor was not correlated with pepsin levels. There was no correlation between BAL fluid neutrophils and pepsin levels. CONCLUSION These data demonstrate lung epithelial lining fluid concentrations of pepsin in lung allograft recipients which are much higher than blood reference levels, with no detectable pepsin in controls. This provides direct evidence of gastric aspiration, which is potentially injurious to the allograft.
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Ward C, Forrest IA, Murphy DM, Johnson GE, Robertson H, Cawston TE, Fisher AJ, Dark JH, Lordan JL, Kirby JA, Corris PA. Phenotype of airway epithelial cells suggests epithelial to mesenchymal cell transition in clinically stable lung transplant recipients. Thorax 2005; 60:865-71. [PMID: 15972366 PMCID: PMC1747194 DOI: 10.1136/thx.2005.043026] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
BACKGROUND Obliterative bronchiolitis in chronic rejection of lung allografts is characterised by airway epithelial damage and fibrosis. The process whereby normal epithelium is lost and replaced by fibroblastic scar tissue is poorly understood, but recent findings suggest that epithelial cells can become fibroblasts through epithelial-mesenchymal transition (EMT). It is hypothesised that EMT occurs in lung allografts and plays a potential role in airway remodelling. METHODS Sixteen stable lung transplant recipients underwent bronchoscopy with bronchoalveolar lavage (BAL), endobronchial biopsies, and bronchial brushings. Biopsy sections were stained for the fibroblast marker S100A4. Brushings were cultured on collagen, stained with anti-S100A4, and examined for further EMT markers including matrix metalloproteinase (MMP) zymographic activity and epithelial invasion through collagen coated filters. RESULTS A median 15% (0-48%) of the biopsy epithelium stained for S100A4 in stable lung transplant recipients and MMP-7 co-localisation was observed. In non-stimulated epithelial cultures from lung allografts, S100A4 staining was identified with MMP-2 and MMP-9 production and zymographic activity. MMP total protein and activity was increased following stimulation with transforming growth factor (TGF)-beta1. Non-stimulated transplant epithelial cells were invasive and penetration of collagen coated filters increased following TGF-beta1 stimulation. CONCLUSIONS This study provides evidence of EMT markers in lung allografts of patients without loss of lung function. The EMT process may represent a final common pathway following injury in more common diseases characterised by airway remodelling.
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Johnson GE, Dowski ER, Cathey WT. Passive ranging through wave-front coding: information and application. APPLIED OPTICS 2000; 39:1700-1710. [PMID: 18345069 DOI: 10.1364/ao.39.001700] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Passive-ranging systems based on wave-front coding are introduced. These single-aperture hybrid optical-digital systems are analyzed by use of linear models and the Fisher information matrix. Two schemes for passive ranging by use of a single aperture and a single image are investigated: (i) estimating the range to an object and (ii) detecting objects over a set of ranges. Theoretical limitations on estimator-error variances are given by use of the Cramer-Rao bounds. Evaluations show that range estimates with less than 0.1% error can be obtained from a single wave-front coded image. An experimental system was also built, and example results are given.
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Higgs HN, Han MH, Johnson GE, Glomset JA. Cloning of a phosphatidic acid-preferring phospholipase A1 from bovine testis. J Biol Chem 1998; 273:5468-77. [PMID: 9488669 DOI: 10.1074/jbc.273.10.5468] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report the molecular cloning and expression of a phosphatidic acid-preferring phospholipase A1 from bovine testis. The open reading frame encoded an 875-amino acid protein with a calculated molecular mass of 97,576 daltons and a pI of 5.61. The sequence included a region similar to a lipase consensus sequence containing the putative active site serine and also included a potential, coiled-coil-forming region. Expression of the open reading frame in COS1 cells resulted in a 20-44-fold increase in phosphatidic acid phospholipase A1 activity over that of control cells. Mutation of the putative active site serine (amino acid 540) demonstrated that it was essential for this increase in enzyme activity. Northern blot analysis revealed at least five different messages with the highest overall message levels in mature testis, but detectable message in all tissues examined. Two possible alternately spliced regions in the open reading frame also were identified. Finally, a search of the data base identified six related proteins: a potential counterpart of the phospholipase A1 in Caenorhabditis elegans, two putative lipases in yeast, and three proteins separately encoded by the Drosophila retinal degeneration B gene and its mouse and human homologues.
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Connolly PJ, Von Schroeder HP, Johnson GE, Kostuik JP. Adolescent idiopathic scoliosis. Long-term effect of instrumentation extending to the lumbar spine. J Bone Joint Surg Am 1995; 77:1210-6. [PMID: 7642667 DOI: 10.2106/00004623-199508000-00011] [Citation(s) in RCA: 114] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We evaluated eighty-three patients in whom adolescent idiopathic scoliosis had been treated with a posterior spinal arthrodesis and Harrington instrumentation extending to the second, third, fourth, or fifth lumbar vertebra. All eighty-three patients completed a questionnaire, and fifty-five patients were also examined clinically and roentgenographically at a follow-up evaluation at an average of twelve years (range, ten to sixteen years). Twelve patients had a type-I curve; twenty-six, a type-II curve; sixteen, a type-III curve; and one, a type-IV curve, according to the classification of King et al. The preoperative Cobb angle of the primary curve averaged 60 degrees and ranged from 40 to 100 degrees. The curve was an average of 35 degrees (range, 15 to 65 degrees) at the most recent follow-up evaluation. Functional assessment with use of information from the questionnaire revealed an average spine score of 81 points (range, 18 to 99 points). On the basis of the score, thirty-five patients were considered to have had an excellent result; twenty, a good result; thirteen, a fair result; and fifteen, a poor result. Sixty-three (76 per cent) of the eighty-three patients had low-back pain compared with thirty (50 per cent) of sixty individuals who served as a control group. This difference was significant (p < 0.001; chi-square test). Eighteen patients (22 per cent) needed additional spinal procedures. Fourteen patients (17 per cent) did not think that the goals of the initial operation had been accomplished.(ABSTRACT TRUNCATED AT 250 WORDS)
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Shelbourne KD, Johnson GE. Outpatient surgical management of arthrofibrosis after anterior cruciate ligament surgery. Am J Sports Med 1994; 22:192-7. [PMID: 8198186 DOI: 10.1177/036354659402200207] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We present a consecutive series of nine patients who were referred to us because of arthrofibrosis (loss of > 15 degrees of extension) after intraarticular anterior cruciate ligament reconstruction using autogenous patellar tendon (eight patients) or semitendinosus (one patient) graft. Eight patients had surgery within 2 weeks of injury. All patients had been immobilized in flexion after the anterior cruciate ligament reconstruction and they had failed to improve despite vigorous physical therapy and other closed methods of treatment. The mean time from anterior cruciate ligament reconstruction to the subsequent surgery was 10.2 months (range, 3 to 14). The patients underwent an outpatient arthroscopic anterior scar resection, notchplasty, a closed knee manipulation for flexion, and extension casting. Serial daily extension cast changes allowed the patients to obtain full extension, which was maintained by a bivalved extension splint for bedtime use. Flexion was actively sought by aggressive outpatient physical therapy. All patients except one noted near-normal ultimate range of motion. One patient could only attain 10 degrees short of flat extension at the end of his rehabilitation and was considered a failed result. At final followup (mean, 31 months), no patient complained of symptoms of instability, all had a normal gait, and all but one were able to return to athletic activities.
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Shelbourne KD, Johnson GE. Locked bucket-handle meniscal tears in knees with chronic anterior cruciate ligament deficiency. Am J Sports Med 1993; 21:779-82; discussion 782. [PMID: 8291626 DOI: 10.1177/036354659302100604] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Because we noticed patients had difficulty regaining full range of motion after surgery for a locked bucket-handle meniscal tear with simultaneous reconstruction for a chronic anterior cruciate ligament tear, we adopted a two-stage procedure for this group of patients. We evaluated the results of a two-stage procedure in the knees of 16 athletes (Group 1) and compared their outcome with the outcome of 16 matched athletes who had been treated with simultaneous repair or removal of the displaced bucket-handle meniscal tear and autogenous patellar tendon anterior cruciate ligament reconstruction (Group 2). Four patients in Group 2 required a second procedure or casting to regain full extension. No patient in Group 1 required a second procedure. One meniscal retear was detected in Group 1. The two-stage procedure also appears to have a number of theoretical advantages: 1) more aggressive use of repair rather than removal of a displaced torn meniscus, 2) prevention of problems in regaining range of motion, 3) allows a second look to judge the success of meniscal repair, and 4) allows time for the patient to prepare for anterior cruciate ligament reconstruction physically, mentally, academically, and socially.
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