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O'Connor DJ, Kerin MJ, Barkley LR. O13: TUMOUR STROMAL CELLS - A CULPRIT IN BREAST CANCER RECURRENCE AFTER NEOADJUVANT CHEMOTHERAPY. Br J Surg 2021. [DOI: 10.1093/bjs/znab117.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
Introduction
The goal of neoadjuvant chemothepaeutics(NACs) and surgical excision of breast cancer is to control and ultimately eliminate the malignant tumour. Despite advances in treatment, a subset of patients will develop disease recurrence. Tumour stromal cells(TSCs) are non-cancerous cells that support malignancy within the tumour microenvironment(TME). In particular, TSCs can suppress the host immune response to tumour. It is unclear if NACs affect the survival of–or alter the immunosuppressive functions of TSCs in breast cancer patients and if this correlates with recurrance or chemoresistance?
Method
TSCs and Tumour Associated Normal Stromal Cells(TANs) were isolated from tissue harvested from breast cancer patients at surgery. Clonogenic survival assays were performed following exposure to increasing doses of Paclitaxel (range 0-1000nM), Cyclophosphamide (range 0-3μM) and Doxorubicin (0-100nM). TSCs were co-cultured with CD4+ and CD8+ T-cells to determine the effect of chemotherapeutics on their ability to suppress T-cell proliferation.
Result
TSCs(n=5) are less susceptible to the cytotoxic effects of chemotherapy compared to TANs with 21%(p-0.0001), 21%(p-0.001) and 15%(p-0.026) more colonies across all doses of Paclitaxel, Cyclophosphamide and Doxorubicin respectively. Chemo naïve TSCs suppressed CD4+ and CD8+ T-Cell proliferation by 44% and 20.5% respectively(p-0.001, p-0.042). Interestingly, Paclitaxel-treated TSCs suppressed CD4+ proliferation by a further 11.1%(p-0.047) and CD8+ proliferation by 35.6%(p-0.017). Additionally, Cyclophosphamide-treated TSCs enhanced CD8+ suppression by 25.6%(p-0.029).
Conclusion
Our data indicate that NACs enhance the immunosuppressive function of TSCs - potentially creating an immune inert TME in vivo. Future studies will explore the correlation between NAC treatment, immunosuppressive activities within patient tumours/blood and recurrence.
Take-home message
After neoadjuvant chemotherapy, Tumour stromal cells are highly immunosuppressive and may contribute to breast cancer recurrence.
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Affiliation(s)
- DJ O'Connor
- Department of Surgery, Lambe Institute, NUI Galway
| | - MJ Kerin
- Department of Surgery, Lambe Institute, NUI Galway
| | - LR Barkley
- Department of Surgery, Lambe Institute, NUI Galway
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2
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Fennelly M, Keane J, Dolan L, Plant BJ, O'Connor DJ, Sodeau JR, Prentice MB. Containment of procedure-associated aerosols by an extractor tent: effect on nebulized drug particle dispersal. J Hosp Infect 2021; 110:108-113. [PMID: 33484782 PMCID: PMC7817412 DOI: 10.1016/j.jhin.2021.01.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 01/12/2021] [Accepted: 01/13/2021] [Indexed: 02/07/2023]
Abstract
Background Several medical procedures involving the respiratory tract are considered as ‘aerosol-generating procedures’. Aerosols from these procedures may be inhaled by bystanders, and there are consequent concerns regarding the transmission of infection or, specific to nebulized therapy, secondary drug exposure. Aim To assess the efficacy of a proprietary high-efficiency-particulate-air-filtering extractor tent on reducing the aerosol dispersal of nebulized bronchodilator drugs. Methods The study was conducted in an unoccupied outpatient room at St. James's Hospital, Dublin, Ireland. A novel real-time, fluorescent particle counter, the Wideband Integrated Bioaerosol Sensor (WIBS), monitored room air continuously for 3 h. Baseline airborne particle count and count during nebulization of bronchodilator drug solutions were recorded. Findings Nebulization within the tent prevented any increase over background level. Nebulization directly into room air resulted in mean fluorescent particle counts of 4.75 x 105/m3 and 4.21 x 105/m3 for Ventolin and Ipramol, respectively, representing more than 400-fold increases over mean background level. More than 99.3% of drug particles were <2 μm in diameter and therefore small enough to enter the lower respiratory tract. Conclusion The extractor tent was completely effective for the prevention of airborne spread of drug particles of respirable size from nebulized therapy. This suggests that extractor tents of this type would be efficacious for the prevention of airborne infection from aerosol-generating procedures during the COVID-19 pandemic.
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Affiliation(s)
- M Fennelly
- Environmental Research Institute, University College Cork, Cork, Ireland; Department of Pathology, University College Cork, Cork, Ireland.
| | - J Keane
- Respiratory Assessment Unit, St. James's Hospital, Dublin, Ireland
| | - L Dolan
- Respiratory Assessment Unit, St. James's Hospital, Dublin, Ireland
| | - B J Plant
- Adult Cystic Fibrosis Centre, Cork University Hospital, Cork, Ireland
| | - D J O'Connor
- School of Chemical and Pharmaceutical Sciences, Technological University Dublin, Dublin, Ireland
| | - J R Sodeau
- Environmental Research Institute, University College Cork, Cork, Ireland
| | - M B Prentice
- Department of Pathology, University College Cork, Cork, Ireland; APC Microbiome Institute, University College Cork, Cork, Ireland.
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3
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Fennelly M, O'Connor DJ, Hellebust S, Murphy N, Casey C, Eustace J, Plant BJ, Sodeau JR, Prentice MB. Effectiveness of a plasma treatment device on microbial air quality in a hospital ward, monitored by culture. J Hosp Infect 2020; 108:109-112. [PMID: 33188867 PMCID: PMC7658605 DOI: 10.1016/j.jhin.2020.11.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 10/26/2020] [Accepted: 11/06/2020] [Indexed: 11/28/2022]
Abstract
This study analysed the effectiveness of plasma treatment on airborne bacteria and surface counts during a 14-day intervention within a four-bedded bay in an adult respiratory ward at Cork University Hospital, Ireland. One-hundred-litre air samples were collected twice daily every weekday for 4 weeks, with settle plates and surface swabs. The plasma treatment did not have an effect on airborne bacteria and fungi that was detectable by culture. However, the possibility that culture-based sampling may be insufficiently sensitive to detect an effect, or that the duration of the study was insufficient for plasma treatment to affect a complex environment, cannot be excluded.
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Affiliation(s)
- M Fennelly
- Environmental Research Institute, University College Cork, Cork, Ireland; Department of Pathology, University College Cork, Cork, Ireland; School of Chemistry, University College Cork, Cork, Ireland.
| | - D J O'Connor
- School of Chemical and Pharmaceutical Sciences, Technological University Dublin, Dublin, Ireland
| | - S Hellebust
- Environmental Research Institute, University College Cork, Cork, Ireland; School of Chemistry, University College Cork, Cork, Ireland
| | - N Murphy
- Adult Cystic Fibrosis Centre, Cork University Hospital, Cork, Ireland
| | - C Casey
- College of Medicine and Health, University College Cork, Cork, Ireland
| | - J Eustace
- Health Research Board Clinical Research Facility-Cork, Cork, Ireland
| | - B J Plant
- Adult Cystic Fibrosis Centre, Cork University Hospital, Cork, Ireland; College of Medicine and Health, University College Cork, Cork, Ireland; APC Microbiome Institute, University College Cork, Cork, Ireland
| | - J R Sodeau
- Environmental Research Institute, University College Cork, Cork, Ireland; School of Chemistry, University College Cork, Cork, Ireland
| | - M B Prentice
- Department of Pathology, University College Cork, Cork, Ireland; College of Medicine and Health, University College Cork, Cork, Ireland; APC Microbiome Institute, University College Cork, Cork, Ireland
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O'Connor DJ, Waters PS, Aucharaz N, Condon E, Coffey JC, Waldron D. Erratum to: 24th Sylvester O'Halloran Perioperative Scientific Symposium. Ir J Med Sci 2016; 185:999. [PMID: 27534544 DOI: 10.1007/s11845-016-1489-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- D J O'Connor
- Department of Surgery, University Hospital Limerick, Limerick, Ireland.
| | - P S Waters
- Department of Surgery, University Hospital Limerick, Limerick, Ireland
| | - N Aucharaz
- Department of Surgery, University Hospital Limerick, Limerick, Ireland
| | - E Condon
- Department of Surgery, University Hospital Limerick, Limerick, Ireland
| | - J C Coffey
- Department of Surgery, University Hospital Limerick, Limerick, Ireland
| | - D Waldron
- Department of Surgery, University Hospital Limerick, Limerick, Ireland
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Legge K, Cutajar D, Wilfert A, Martin J, Rozenfeld A, O'Connor DJ, Greer P. SU-F-T-328: Real-Time in Vivo Dosimetry of Prostate SBRT Boost Treatments Using MOSkin Detectors. Med Phys 2016. [DOI: 10.1118/1.4956513] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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6
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J Zwan B, Colvill E, Booth J, J O'Connor D, Keall P, B Greer P. TH-AB-202-02: Real-Time Verification and Error Detection for MLC Tracking Deliveries Using An Electronic Portal Imaging Device. Med Phys 2016. [DOI: 10.1118/1.4958066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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7
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Zwan BJ, Barnes M, Hindmarsh J, Seymour E, O'Connor DJ, Keall PJ, Greer PB. MO-FG-202-04: Gantry-Resolved Linac QA for VMAT: A Comprehensive and Efficient System Using An Electronic Portal Imaging Device. Med Phys 2016. [DOI: 10.1118/1.4957306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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8
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Legge K, Nguyen D, Ng J, Wilton L, Booth J, Keall P, Martin J, O'Connor DJ, Greer P. SU-G-JeP4-10: Measurement of Prostate Motion Trajectories During Prostate SBRT Boost Treatments with a Rectafix. Med Phys 2016. [DOI: 10.1118/1.4957120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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9
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O'Lee A, O'Connor D, O'Connor DJ. Endovascular approaches to the ascending aorta for repair with straight and branched endografts: techniques and for what lesions. J Cardiovasc Surg (Torino) 2015; 56:1-9. [PMID: 25394878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Traditionally ascending aortic lesions have been repaired in open fashion: stenotomy, cardiopulmonary bypass, with or without deep hypothermic circulatory arrest. However, a subsegment of patients are deemed too high risk for open intervention. In the advent of endovascular advancement, this subset of patients may be treated with the use of stents (physician made, off-label use), branched stents, through a variety of methods and approaches. Although there are currently no large randomized, prospective studies, success has been seen in smaller case series. This review article addresses the identification of anatomy amenable to endovascular repair for management of type A aortic dissection, pseudoaneurysm, and zone 0 lesions. Different approaches to repair, including transapical, transeptal, femoral, common carotid, and axillary graft insertion are also examined. For endovascular treatment of ascending aortic lesions to grow as a field, devices made specifically for the ascending aorta need to be designed and larger trials are necessary to evaluate the rates of complications, morbidity, and mortality, and graft patency.
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Affiliation(s)
- A O'Lee
- Division of Vascular Surgery Heart and Vascular Hospital Hackensack University Medical Center Hackensack, NJ, USA -
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10
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O'Connor DJ, Wright GC, Dieters MJ, George DL, Hunter MN, Tatnell JR, Fleischfresser DB. Development and Application of Speed Breeding Technologies in a Commercial Peanut Breeding Program. ACTA ACUST UNITED AC 2013. [DOI: 10.3146/ps12-12.1] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
ABSTRACT
Reducing the release time of new peanut varieties is a key objective of peanut breeding programs. In the Australian Peanut Genetic Improvement Program release time has traditionally taken 10 to 15 years; however, the relatively recent use of winter breeding and seed increase nurseries has significantly reduced release times. Despite these improvements, full-season maturity cultivars are still limited to two generations in a calendar year, when grown under optimal environmental conditions. This paper describes a new speed breeding technique, which combines controlled environment conditions, continuous light in conjunction with optimal temperature, and a single seed descent breeding strategy in a greenhouse environment. Speed breeding was successful in reducing generation time of full-season maturity cultivars from 145 to 89 days. Speed breeding can rapidly progress the inbreeding of F2, F3 and F4 generations in less than 12 months, and potentially accelerate the development of first cross to commercial release in around six to seven years.
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Affiliation(s)
- D. J. O'Connor
- Research Scholar, The University of Queensland, School of Agriculture and Food Sciences, St Lucia, QLD, 4072
| | - G. C. Wright
- Manager (Breeding, Seed and Innovation), Peanut Company of Australia, Haly St, Kingaroy, QLD 4610
| | - M. J. Dieters
- Senior Lecturer, The University of Queensland, School of Agriculture and Food Sciences, St Lucia, QLD, 4072
| | - D. L. George
- Senior Lecturer, The University of Queensland, School of Agriculture and Food Sciences, St Lucia, QLD, 4072
| | - M. N. Hunter
- Honorary Senior Fellow, The University of Queensland, School of Agriculture and Food Sciences, St Lucia, QLD, 4072
| | - J. R. Tatnell
- Senior Experimentalist, Department of Agriculture, Fisheries and Forestry, 213 Goodger Rd, Kingaroy, QLD, 4610
| | - D. B. Fleischfresser
- Senior Experimentalist, Department of Agriculture, Fisheries and Forestry, 213 Goodger Rd, Kingaroy, QLD, 4610
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11
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O'Connor DJ, Wong RWK, Rabie ABM. Resveratrol Inhibits Periodontal PathogensIn Vitro. Phytother Res 2011; 25:1727-31. [DOI: 10.1002/ptr.3501] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Revised: 03/14/2011] [Accepted: 03/17/2011] [Indexed: 11/10/2022]
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Rowshanfarzad P, Sabet M, O'Connor DJ, Greer PB. Sci-Sat AM(2): Brachy - 07: Amelioration of the Effect of Non-Uniform Arm Backscatter on Dosimetry with a Varian A-Si EPID. Med Phys 2010. [DOI: 10.1118/1.3476219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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13
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14
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Fallis LH, Richards E, O'Connor DJ, Zhong S, Hsieh JK, Packham G, Lu X. The biological response of MCF7 breast cancer cells to proteosome inhibition or gamma-radiation is unrelated to the level of p53 induction. Apoptosis 2003; 4:99-107. [PMID: 14634287 DOI: 10.1023/a:1009614726059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The p53 tumour suppressor is stabilised following exposure to genotoxic agents, such as gamma-radiation. Cell responses to p53 stabilisation include induction of apoptosis and/or cell cycle arrest. Several studies have suggested that gamma-radiation stabilises p53 by blocking ubiquitin mediated proteolysis. Here we have compared the biological activities of p53 stabilized following exposure to gamma-radiation or treatment with the proteosome inhibitor N-acetyl-leucinyl-leucinyl-norleucinal (ALLN) in MCF7 cells with wild type p53. Stabilisation of p53 by ALLN was reversible and was not blocked by caffeine. Although ALLN was a more effective p53 stabilising agent than gamma-radiation, ALLN was not as effective at inducing cell cycle arrest/apoptosis as gamma-radiation. Although p53 stabilised by ALLN and gamma-radiation were both able to bind DNA and activate transcription, ALLN did not increase expression of BAX, which is involved in p53-induced apoptosis. Therefore, p53 stabilised by different agents is not always biologically active to the same extent and additional alterations triggered by gamma-radiation may enable p53 to activate a subset of critical target genes, such as BAX, which are required for p53 responses.
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Affiliation(s)
- L H Fallis
- Ludwig Institute for Cancer Research, Imperial College School of Medicine, St. Mary's Campus, Norfolk Place, London, W2 1PG, UK
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15
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Samuels-Lev Y, O'Connor DJ, Bergamaschi D, Trigiante G, Hsieh JK, Zhong S, Campargue I, Naumovski L, Crook T, Lu X. ASPP proteins specifically stimulate the apoptotic function of p53. Mol Cell 2001; 8:781-94. [PMID: 11684014 DOI: 10.1016/s1097-2765(01)00367-7] [Citation(s) in RCA: 526] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
We identified a family of proteins termed ASPP. ASPP1 is a protein homologous to 53BP2, the C-terminal half of ASPP2. ASPP proteins interact with p53 and specifically enhance p53-induced apoptosis but not cell cycle arrest. Inhibition of endogenous ASPP function suppresses the apoptotic function of endogenous p53 in response to apoptotic stimuli. ASPP enhance the DNA binding and transactivation function of p53 on the promoters of proapoptotic genes in vivo. Two tumor-derived p53 mutants with reduced apoptotic function were defective in cooperating with ASPP in apoptosis induction. The expression of ASPP is frequently downregulated in human breast carcinomas expressing wild-type p53 but not mutant p53. Therefore, ASPP regulate the tumor suppression function of p53 in vivo.
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Affiliation(s)
- Y Samuels-Lev
- Ludwig Institute for Cancer Research, Imperial College School of Medicine, St. Mary's Campus, Norfolk Place, London W2 1PG, United Kingdom
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16
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Abstract
PURPOSE To report a randomized clinical trial of postoperative subconjunctival injections of low-dose 5-fluorouracil in patients undergoing primary trabeculectomy. METHODS In a prospective, randomized clinical trial, 40 eyes of 40 patients were randomized to the low-dose 5-fluorouracil group and received three subconjunctival injections of 5 mg each over 11 postoperative days, and 40 eyes of 40 patients were randomized to trabeculectomy without 5-fluorouracil. RESULTS Mean (+/-SD) preoperative and 1-year postoperative intraocular pressures in the 5-fluorouracil group were 26.9 (+/-9.5) and 15.3 (+/-5.8) mm Hg, respectively. In the control group these were 25.9 (+/-8.1) mm Hg, and 15.8 (+/-5.1) mm Hg, respectively. The patients who received 5-fluorouracil had a mean reduction in intraocular pressure of 11.5 (+/-9.1) mm Hg at a median follow-up of 52.3 weeks. The control group had a mean reduction in intraocular pressure of 10.2 (+/-8.7) mm Hg at a median follow-up of 52.6 weeks. These differences were not statistically significant. CONCLUSIONS Three postoperative subconjunctival 5-fluorouracil injections of 5 mg each after trabeculectomy in eyes at low risk for failure had no statistically or clinically significant effect on reduction of intraocular pressure with 1-year follow-up. Enhancement of success in this group of patients may require a larger total dose of 5-fluorouracil.
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Affiliation(s)
- I A Chaudhry
- Department of Ophthalmology and Visual Sciences, Yale University School of Medicine and Yale-New Haven Hospital, New Haven, Connecticut, USA
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17
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Lopez CD, Ao Y, Rohde LH, Perez TD, O'Connor DJ, Lu X, Ford JM, Naumovski L. Proapoptotic p53-interacting protein 53BP2 is induced by UV irradiation but suppressed by p53. Mol Cell Biol 2000; 20:8018-25. [PMID: 11027272 PMCID: PMC86412 DOI: 10.1128/mcb.20.21.8018-8025.2000] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
p53 is an important mediator of the cellular stress response with roles in cell cycle control, DNA repair, and apoptosis. 53BP2, a p53-interacting protein, enhances p53 transactivation, impedes cell cycle progression, and promotes apoptosis through unknown mechanisms. We now demonstrate that endogenous 53BP2 levels increase following UV irradiation induced DNA damage in a p53-independent manner. In contrast, we found that the presence of a wild-type (but not mutant) p53 gene suppressed 53BP2 steady-state levels in cell lines with defined p53 genotypes. Likewise, expression of a tetracycline-regulated wild-type p53 cDNA in p53-null fibroblasts caused a reduction in 53BP2 protein levels. However, 53BP2 levels were not reduced if the tetracycline-regulated p53 cDNA was expressed after UV damage in these cells. This suggests that UV damage activates cellular factors that can relieve the p53-mediated suppression of 53BP2 protein. To address the physiologic significance of 53BP2 induction, we utilized stable cell lines with a ponasterone A-regulated 53BP2 cDNA. Conditional expression of 53BP2 cDNA lowered the apoptotic threshold and decreased clonogenic survival following UV irradiation. Conversely, attenuation of endogenous 53BP2 induction with an antisense oligonucleotide resulted in enhanced clonogenic survival following UV irradiation. These results demonstrate that 53BP2 is a DNA damage-inducible protein that promotes DNA damage-induced apoptosis. Furthermore, 53BP2 expression is highly regulated and involves both p53-dependent and p53-independent mechanisms. Our data provide new insight into 53BP2 function and open new avenues for investigation into the cellular response to genotoxic stress.
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Affiliation(s)
- C D Lopez
- Divisions of Medical Oncology, Department of Pediatrics, Stanford University School of Medicine, Stanford, California 94305, USA.
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18
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Abstract
One of the common features of cellular response to stress is cell cycle arrest or apoptosis. E2F is one of the key factors which controls cell cycle progression. Overexpression of E2F-1 can also induce apoptosis. In order to understand the role of E2F-1 in cellular response to stress, we studied the E2F-1 response in various cell lines to different types of stress signals including UV irradiation, cisplatin, etoposide and hypoxia. We showed here that the expression level of E2F-1 can be up regulated by the treatment of DNA damage agents as well as hypoxia. The kinetics of E2F-1 increase was dependent on the types of inducer and was similar to that of p53. However, stress signals can induce E2F-1 expression independently of p53 and Rb. Furthermore, the induced E2F-1 was transcriptionally inactive. All these results suggested that E2F-1 may play a very important role in cellular response to stress and this novel role of E2F-1 is independent of its transactivation function.
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Affiliation(s)
- D J O'Connor
- Ludwig Institute for Cancer Research, Imperial College of Science, Technology and Medicine at St. Mary's Campus, Norfolk Place, London W2 1PG, UK
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19
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Abstract
The original concept for the heat stress limits adopted by the American Conference of Governmental Industrial Hygienists (ACGIH) was that the threshold for heat stress can be marked by environmental conditions (WBGT) that are adjusted for metabolic rate. The underlying data were based on ordinary work clothes. The Physical Agents Committee promoted clothing adjustment factors within the industrial hygiene community through a revision in the TLVs for heat stress in 1990. As approved, there were adjustment factors for three other clothing ensembles. To extend and further understand adjustment factors, adjustments for commercially available clothing ensembles and prototype ensembles have been examined. The fundamental principle of the assignment of an adjustment factor to an ensemble begins with establishing critical environmental conditions in which test subjects were just able to maintain thermal equilibrium. Four or five subjects for each ensemble walked on a tread-mill inside a climatic chamber under controlled conditions of heat stress. During each test, heart rate and core temperature were continuously monitored. After a physiological steady-state was achieved, temperature and humidity were slowly increased to maintain relative humidity at 20 percent, 50 percent, or 70 percent. Metabolic rate was assessed by measuring the rate of oxygen consumption. Reviewing a trial, the critical conditions were noted as the time when thermal regulatory control was lost (called the inflection point and marked by a steady increase in core temperature). The climatic conditions at the inflection point were used to assign a critical WBGT. A WBGT representative of each ensemble was assigned through a weighted average of different protocols. Clothing adjustment factors representing an equivalent increase in WBGT were computed by noting the difference between the representative WBGT of the cotton work clothes and the other clothing ensembles. The results suggested adjustment factors with reference to ordinary work clothes from the least stress at -2.1 to 5.5 degrees C-WBGT. The adjustment factors were reasonably well predicted by a linear regression based on a computed value for total evaporative resistance (r2 = 0.92).
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Affiliation(s)
- D J O'Connor
- College of Public Health, University of South Florida, Tampa, USA
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20
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Abstract
The binding of RB to MDM2 is shown to be essential for RB to overcome both the antiapoptotic function of MDM2 and the MDM2-dependent degradation of p53. The RB-MDM2 interaction does not prevent MDM2 from inhibiting p53-dependent transcription, but the RB-MDM2 complex still binds to p53. Since RB specifically rescues the apoptotic function but not the transcriptional activity of p53 from negative regulation by MDM2, transactivation by wild-type p53 is not required for the apoptotic function of p53. However, an RB-MDM2-p53 trimeric complex is active in p53-mediated transrepression. These data link directly the function of two tumor suppressor proteins and demonstrate a novel role of RB in regulating the apoptotic function of p53.
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Affiliation(s)
- J K Hsieh
- Ludwig Institute for Cancer Research, Imperial College School of Medicine, London, United Kingdom
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21
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Lu QB, Souda R, O'Connor DJ, King BV. Interaction of oxygen with a Cs-monolayer-covered Si(100) surface. Phys Rev B Condens Matter 1996; 54:R17347-R17350. [PMID: 9985954 DOI: 10.1103/physrevb.54.r17347] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Lu QB, Souda R, O'Connor DJ, King BV. Electronic-Structure Modification and the Adsorption Site of Oxygen on Alkali (Cs) Covered Surfaces Studied by Normal Exit Li- Ion Spectroscopy. Phys Rev Lett 1996; 77:3236-3239. [PMID: 10062168 DOI: 10.1103/physrevlett.77.3236] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Lu QB, Souda R, O'Connor DJ, King BV, MacDonald RJ. Electronic-structure effect on core-level excitation and charge transfer in ions scattering from alkali-metal-covered surfaces. Phys Rev B Condens Matter 1996; 54:R8389-R8392. [PMID: 9984602 DOI: 10.1103/physrevb.54.r8389] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Zhang FM, King BV, O'Connor DJ. Low energy ion scattering investigation of the order-disorder transition in the first atomic layer of the Cu3Au(100) surface. Phys Rev Lett 1995; 75:4646-4649. [PMID: 10059962 DOI: 10.1103/physrevlett.75.4646] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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O'Connor DJ, Lam EW, Griffin S, Zhong S, Leighton LC, Burbidge SA, Lu X. Physical and functional interactions between p53 and cell cycle co-operating transcription factors, E2F1 and DP1. EMBO J 1995; 14:6184-92. [PMID: 8557038 PMCID: PMC394743 DOI: 10.1002/j.1460-2075.1995.tb00309.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
One way in which wild-type p53 is able to regulate cell cycle progression is thought to be via the induction of its downstream target gene Waf1/CIP1, thus indirectly regulating the transcriptional activity of E2F. The E2F transcription factors are known to be key effectors of the cell cycle. We report here that there is a physical and functional interaction between p53 and two of the components of the E2F transcription factors, E2F1 and DP1. The expression of wild-type p53 can inhibit the transcriptional activity of E2F, and the expression of both E2F1 and DP1 can also downregulate p53-dependent transcription. The transcriptional activity of p53 is known to be inhibited by the direct binding of mdm2, but we demonstrate here that both E2F1 and DP1 can inhibit p53 transcriptional activity independently of mdm2. Detailed studies of protein-protein interactions have provided evidence that E2F1 and its co-operating factor DP1 can complex with p53 both in vitro and in vivo.
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Affiliation(s)
- D J O'Connor
- Ludwig Institute for Cancer Research, St Mary's Hospital Medical School, London, UK
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Abstract
PURPOSE Various techniques of optic disc and nerve fiber layer evaluation may be used to detect structural glaucomatous damage. The authors compared several qualitative and quantitative methods to determine their relative sensitivities and specificities to detect the presence of glaucomatous visual field loss. METHODS Fifty-one healthy eyes, 169 ocular hypertensive eyes with normal visual fields, and 132 glaucomatous eyes with early visual field defects were evaluated with qualitative and quantitative measures of structural damage to the optic nerve and nerve fiber layer. Qualitative evaluations were performed by three experienced masked observers who independently graded stereoscopic color disc and monochromatic nerve fiber layer photographs. Quantitative measurements of disc rim area and nerve fiber layer height were made with digitized image analysis of videographic images. Manual planimetric measurements of disc rim area were made from enlarged prints of stereoscopic optic disc photographs. Diagnostic precision was defined as the total proportion of correct diagnoses for the presence or absence of visual field loss. RESULTS The diagnostic precision of results of a quantitative disc examination (81%) was greater than those of a qualitative nerve fiber layer examination (75%). Quantitative nerve fiber height measurement had the highest sensitivity rate (73%) and results of the qualitative disc examination had the highest specificity rate (87%) of the methods tested. CONCLUSION The diagnostic precision of disc evaluation was superior to other methods, including nerve fiber layer examination, in correctly determining the presence of structural glaucomatous damage at the early visual field loss stage.
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Affiliation(s)
- D J O'Connor
- Department of Ophthalmology and Visual Sciences, Yale University School of Medicine, New Haven, CT 06510
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Shen YG, O'Connor DJ, MacDonald RJ. Studies of surface composition, structure and oxygen adsorption of Ni3Al(110) by Li+ and He+ ion scattering. SURF INTERFACE ANAL 1992. [DOI: 10.1002/sia.740181007] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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O'Connor DJ, Tressler CS, Caprioli J. A surgical method to repair leaking filtering blebs. Ophthalmic Surg 1992; 23:336-8. [PMID: 1603534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Surgical revision of a chronically-thinned filtering bleb with a leak at the limbus is described. After surgical excision of the scarred cystic conjunctiva and Tenon's fascia surrounding the leaking bleb, relatively uninvolved conjunctiva and Tenon's fascia are mobilized with the help of a large relaxing incision in the superior fornix and sutured over the area of filtration. We have used this technique successfully in five cases to provide fresh tissue to repair the bleb leak and restore adequate filtration.
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Affiliation(s)
- D J O'Connor
- Yale University School of Medicine, Department of Ophthalmology and Visual Science, New Haven, CT 06510
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Abstract
Recent studies have demonstrated an increased incidence in the diagnosis of malignancy subsequent to the diagnosis of deep venous thrombosis or pulmonary embolus. We reviewed 237 patients with venographically proven deep venous thrombosis over eight years. Of these, 216 had at least one predisposing cause for deep venous thrombosis; of the remaining 21 patients, three had hemoglobin determinations revealing anemia and were subsequently shown to have a malignant disease. One patient had two chief complaints and was shown to have deep venous thrombosis and malignant disease. The 17 remaining patients underwent computed tomographic scan of the abdomen and seven (41%) had abnormalities which proved to be malignant in origin. One further patient was diagnosed with carcinoma of the cervix two months following the onset of deep venous thrombosis. The remaining 10 patients continued free of malignant disease. Five have died of circulatory causes in the follow-up period. Seven of the nine patients diagnosed with malignancy succumbed within six months of the diagnosis. We conclude that only a small group of patients with deep venous thrombosis will have no identifiable cause for deep venous thrombosis and be asymptomatic for malignancy. Complete blood count, physical examination and computed tomographic scan of the abdomen at the time of venographic diagnosis of deep venous thrombosis is useful in diagnosis of "occult" malignancy. The number of gynecologic tumors would suggest the need for pelvic examination as well as radiographic examination. The presence of deep venous thrombosis and malignant disease is an ominous prognostic sign.
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Affiliation(s)
- N A Sannella
- Department of Surgery, St. John's Hospital, Lowell, Massachusetts
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31
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Abstract
The study of surfaces has progressed by the development of techniques which use different probing species in the form of electrons, ions and photons. Specialisation within the use of each probe has resulted in the subsequent development of methods of analysis tuned to obtain specific information about a surface. In this presentation the various uses of ion scattering spectrometry over a wide range of energies will be reviewed to illustrate how it has been successfully used to yield structural and compositional information of the surface atomic layer and the near surface region.
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Snowdon KJ, O'Connor DJ, MacDonald RJ. Observation of skipping motion in small-angle ion-surface scattering. Phys Rev Lett 1988; 61:1760-1763. [PMID: 10038889 DOI: 10.1103/physrevlett.61.1760] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Snowdon KJ, O'Connor DJ, MacDonald RJ. Observation of transient adsorption or skipping motion in small angle ion-surface scattering. ACTA ACUST UNITED AC 1988. [DOI: 10.1007/bf00619702] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Hu BL, O'Connor DJ. Symmetry behavior in curved spacetime: Finite-size effect and dimensional reduction. Phys Rev D Part Fields 1987; 36:1701-1715. [PMID: 9958353 DOI: 10.1103/physrevd.36.1701] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Shen TC, Hu BL, O'Connor DJ. Symmetry behavior of the static Taub universe: Effect of curvature anisotropy. Phys Rev D Part Fields 1985; 31:2401-2423. [PMID: 9955538 DOI: 10.1103/physrevd.31.2401] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Ferron KR, Burke PA, O'Connor DJ. Radiology services' study improves productivity, care. Hosp Prog 1982; 63:50-1. [PMID: 10255571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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O'Connor DJ, Diters RW, Nielsen SW. Poxvirus and multiple tumors in an eastern gray squirrel. J Am Vet Med Assoc 1980; 177:792-5. [PMID: 6256332] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A moribund juvenile gray squirrel (Sciurus carolinensis) with numerous skin fibromas was submitted to the Northeastern Research Center for Wildlife Diseases. Necropsy revealed multiple firm white nodules in the lungs. On histologic examination, in addition to the skin lesions, fibromatous proliferations were seen in the wall of the alimentary tract, in 1 mesenteric lymph node, and in the myocardium. Tubular adenomas were seen in the renal cortex, and the lung nodules were bronchoalveolar adenomas. Eosinophilic intracytoplasmic poxvirus inclusion bodies were seen in both the mesenchymal and epithelial tumors.
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Abstract
An outbreak of staphylococcal mastitis in nursing female ranch mink (Mustela vison) is described. Lesions were acute necrotizing mastitis, fatty infiltration of the liver and renal tubules, and adrenal cortical hyperplasia. The presence of Aleutian disease in the herd suggests a role of immunosuppression in the outbreak.
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Schachat F, O'Connor DJ, Epstein HF. The moderately repetitive DNA sequences of Caenorhabditis elegans do not show short-period interspersion. Biochim Biophys Acta 1978; 520:688-92. [PMID: 718922 DOI: 10.1016/0005-2787(78)90154-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In these studies we show that the moderately repetitive DNA sequences of Caenorhabditis elegans are not arranged in the characteristic short-period interspersion pattern of most eukaryotes. Rather, the moderately repetitive sequences are arranged in long arrays as in Drosophila and Apis. These findings indicate that this type of arrangement is more phylogenetically diverse and hence less exceptional than previously believed.
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O'Connor DJ, Chang DT, Shey MI. Computed tomography in a community hospital. Radiology 1976; 119:601-2. [PMID: 935395 DOI: 10.1148/119.3.601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Computed tomography may be effectively utilized in the radiology department of a community hospital. An ideal program features regional services, 7-day, 24-hour coverage, immediate response to emergencies, prompt reporting, and availability of ancillary hospital services. Experience indicates that early scanning may eliminate the need for invasive diagnostic procedures, prevent or shorten hospital stay, and minimize the morbidity and expense of neuroradiological diagnosis.
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O'Connor DJ. An analysis of the dissolved oxygen distribution in the East River. J Water Pollut Control Fed 1966; 38:1813-30. [PMID: 5979391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Patterson JH, O'Connor DJ. Chemical studies of amphibole asbestos. I. Structural changes of heat-treated crocidolite, amosite, and tremolite from infrared absorption studies. Aust J Chem 1966. [DOI: 10.1071/ch9661155] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The thermal dehydroxylation,
oxidation, and decomposition of the amphiboles: crocidolite, amosite, and
tremolite have been investigated with infrared spectroscopy. Changes in the
spectra with temperature have been related to these processes.
The dehydroxylation
of crocidolite and amosite
in air causes only small structural rearrangements but dehydration of tremolite occurs at higher temperatures during
decomposition of the amphibole structure. For both crocidolite
and amosite the temperature of dehydroxylation
is higher and the decomposition temperature lower in vacuum than in air. These
differences are discussed in terms of variation in chemical composition and
changes in the mechanism of dehydroxylation. For crocidolite it is suggested that certain hydroxyl groups
are removed preferentially.��� Small structural rearrangements associated
with oxidation and dehydroxylation cause a broadening
and shifting of the main absorption bands but decomposition of the structure
produces marked changes in the spectra.
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Orey S, Basson AH, O'Connor DJ. Introduction to Symbolic Logic. J Am Stat Assoc 1962. [DOI: 10.2307/2282488] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Bryant F, O'Connor DJ. The adsorption of aspartic acid and glycine on sparingly soluble inorganic solids. Aust J Chem 1958. [DOI: 10.1071/ch9580125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
An investigation has
been made of the adsorption of aspartic acid and glycine on a series of natural
and synthetic sparingly soluble inorganic solids. The amino acids have been
analysed by a photographic development of the Fisher-Parsons-Morrison relationship
found to exist for paper chromatograms.
Aspartic acid was found
to be adsorbed in greater amounts than glycine. Natural samples showed higher
adsorptive capacities for both acids than did the synthetic samples. Adsorption
capacities of the solids investigated were considerably higher than those found
by previous workers for similar solids. No correlation has been found between
adsorptive capacities and known electrokinetic properties of the adsorbents.
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