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Choi WM, Yip TCF, Kim WR, Yee LJ, Brooks-Rooney C, Curteis T, Clark LJ, Jafry Z, Chen CH, Chen CY, Huang YH, Jin YJ, Jun DW, Kim JW, Park NH, Peng CY, Shin HP, Shin JW, Yang YH, Wong GLH, Lim YS. Chronic hepatitis B baseline viral load and on-treatment liver cancer risk: A multinational cohort study of HBeAg-positive patients. Hepatology 2024:01515467-990000000-00726. [PMID: 38436992 DOI: 10.1097/hep.0000000000000752] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 12/12/2023] [Indexed: 03/05/2024]
Abstract
BACKGROUND AND AIMS A single-nation study reported that pretreatment HBV viral load is associated with on-treatment risk of HCC in patients who are HBeAg-positive without cirrhosis and with chronic hepatitis B initiating antiviral treatment. We aimed to validate the association between baseline HBV viral load and on-treatment HCC risk in a larger, multinational cohort. APPROACH AND RESULTS Using a multinational cohort from Korea, Hong Kong, and Taiwan involving 7545 adult patients with HBeAg-positive, without cirrhosis and with chronic hepatitis B who started entecavir or tenofovir treatment with baseline HBV viral load ≥5.00 log 10 IU/mL, HCC risk was estimated by baseline viral load. HBV viral load was analyzed as a categorical variable. During continuous antiviral treatment (median, 4.28 y), HCC developed in 200 patients (incidence rate, 0.61 per 100 person-years). Baseline HBV DNA level was independently associated with on-treatment HCC risk in a nonlinear pattern. HCC risk was lowest with the highest baseline viral load (≥8.00 log 10 IU/mL; incidence rate, 0.10 per 100 person-years), but increased sharply as baseline viral load decreased. The adjusted HCC risk was 8.05 times higher (95% CI, 3.34-19.35) with baseline viral load ≥6.00 and <7.00 log 10 IU/mL (incidence rate, 1.38 per 100 person-years) compared with high (≥8.00 log 10 IU/mL) baseline viral load ( p <0.001). CONCLUSIONS In a multinational cohort of adult patients with HBeAg-positive without cirrhosis and with chronic hepatitis B, baseline HBV viral load was significantly associated with HCC risk despite antiviral treatment. Patients with the highest viral load who initiated treatment had the lowest long-term risk of HCC development.
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Affiliation(s)
- Won-Mook Choi
- Department of Gastroenterology, Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Terry Cheuk-Fung Yip
- Department of Medicine and Therapeutics, Medical Data Analytics Centre, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - W Ray Kim
- Department of Medicine, Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, California, USA
| | | | | | | | | | - Zarena Jafry
- Costello Medical Inc, Boston, Massachusetts, USA
| | - Chien-Hung Chen
- Department of Internal Medicine, Division of Hepatogastroenterology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Chi-Yi Chen
- Department of Internal Medicine, Division of Hepatogastroenterology, Ditmanson Medical Foundation Chia-Yi Christian Hospital, Chia-Yi, Taiwan
| | - Yi-Hsiang Huang
- Department of Medicine, Division of Gastroenterology and Hepatology, Taipei Veterans General Hospital, Taipei, Taiwan
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Young-Joo Jin
- Department of Internal Medicine, Digestive Disease Center, Inha University Hospital, Inha University School of Medicine, Incheon, Korea
| | - Dae Won Jun
- Department of Internal Medicine, Hanyang University Hospital, Hanyang University College of Medicine, Seoul, Korea
| | - Jin-Wook Kim
- Department of Medicine, Seoul National University Bundang Hospital, Seongnam, Korea
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Neung Hwa Park
- Department of Internal Medicine, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Korea
- Biomedical Research Center, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Korea
| | - Cheng-Yuan Peng
- Department of Internal Medicine, Center for Digestive Medicine, China Medical University Hospital, Taichung, Taiwan
- School of Medicine, China Medical University, Taichung, Taiwan
| | - Hyun Phil Shin
- Department of Gastroenterology and Hepatology, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, Seoul, Korea
| | - Jung Woo Shin
- Department of Internal Medicine, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Korea
| | - Yao-Hsu Yang
- Department of Traditional Chinese Medicine, Chiayi Chang Gung Memorial Hospital, Chiayi, Taiwan
- Health Information and Epidemiology Laboratory, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Grace Lai-Hung Wong
- Department of Medicine and Therapeutics, Medical Data Analytics Centre, The Chinese University of Hong Kong, Hong Kong SAR, China
| | - Young-Suk Lim
- Department of Gastroenterology, Liver Center, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
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Kelly JD, Curteis T, Rawal A, Murton M, Clark LJ, Jafry Z, Shah-Gupta R, Berry M, Espinueva A, Chen L, Abdelghany M, Sweeney DA, Quint JK. SARS-CoV-2 post-acute sequelae in previously hospitalised patients: systematic literature review and meta-analysis. Eur Respir Rev 2023; 32:220254. [PMID: 37437914 PMCID: PMC10336551 DOI: 10.1183/16000617.0254-2022] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [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] [Received: 12/19/2022] [Accepted: 04/03/2023] [Indexed: 07/14/2023] Open
Abstract
BACKGROUND Many individuals hospitalised with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection experience post-acute sequelae of SARS-CoV-2 infection (PASC), sometimes referred to as "long COVID". Our objective was to conduct a systematic literature review and meta-analysis to identify PASC-associated symptoms in previously hospitalised patients and determine the frequency and temporal nature of PASC. METHODS Searches of MEDLINE, Embase, Cochrane Library (2019-2021), World Health Organization International Clinical Trials Registry Platform and reference lists were performed from November to December 2021. Articles were assessed by two reviewers against eligibility criteria and a risk of bias tool. Symptom data were synthesised by random effects meta-analyses. RESULTS Of 6942 records, 52 studies with at least 100 patients were analysed; ∼70% were Europe-based studies. Most data were from the first wave of the pandemic. PASC symptoms were analysed from 28 days after hospital discharge. At 1-4 months post-acute SARS-CoV-2 infection, the most frequent individual symptoms were fatigue (29.3% (95% CI 20.1-40.6%)) and dyspnoea (19.6% (95% CI 12.8-28.7%)). Many patients experienced at least one symptom at 4-8 months (73.1% (95% CI 44.2-90.3%)) and 8-12 months (75.0% (95% CI 56.4-87.4%)). CONCLUSIONS A wide spectrum of persistent PASC-associated symptoms were reported over the 1-year follow-up period in a significant proportion of participants. Further research is needed to better define PASC duration and determine whether factors such as disease severity, vaccination and treatments have an impact on PASC.
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Affiliation(s)
- J Daniel Kelly
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA
| | | | | | | | | | - Zarena Jafry
- Costello Medical Consulting, Inc., Boston, MA, USA
| | | | - Mark Berry
- Gilead Sciences Europe Ltd, Uxbridge, UK
| | | | - Linda Chen
- Gilead Sciences, Inc., Foster City, CA, USA
| | | | - Daniel A Sweeney
- Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of California, San Diego, CA, USA
| | - Jennifer K Quint
- School of Public Health and National Heart and Lung Institute, Imperial College London, London, UK
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Westhoek A, Clark LJ, Culbert M, Dalchau N, Griffiths M, Jorrin B, Karunakaran R, Ledermann R, Tkacz A, Webb I, James EK, Poole PS, Turnbull LA. Conditional sanctioning in a legume- Rhizobium mutualism. Proc Natl Acad Sci U S A 2021; 118:e2025760118. [PMID: 33941672 PMCID: PMC8126861 DOI: 10.1073/pnas.2025760118] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Legumes are high in protein and form a valuable part of human diets due to their interaction with symbiotic nitrogen-fixing bacteria known as rhizobia. Plants house rhizobia in specialized root nodules and provide the rhizobia with carbon in return for nitrogen. However, plants usually house multiple rhizobial strains that vary in their fixation ability, so the plant faces an investment dilemma. Plants are known to sanction strains that do not fix nitrogen, but nonfixers are rare in field settings, while intermediate fixers are common. Here, we modeled how plants should respond to an intermediate fixer that was otherwise isogenic and tested model predictions using pea plants. Intermediate fixers were only tolerated when a better strain was not available. In agreement with model predictions, nodules containing the intermediate-fixing strain were large and healthy when the only alternative was a nonfixer, but nodules of the intermediate-fixing strain were small and white when the plant was coinoculated with a more effective strain. The reduction in nodule size was preceded by a lower carbon supply to the nodule even before differences in nodule size could be observed. Sanctioned nodules had reduced rates of nitrogen fixation, and in later developmental stages, sanctioned nodules contained fewer viable bacteria than nonsanctioned nodules. This indicates that legumes can make conditional decisions, most likely by comparing a local nodule-dependent cue of nitrogen output with a global cue, giving them remarkable control over their symbiotic partners.
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Affiliation(s)
- Annet Westhoek
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom
- Systems Biology Doctoral Training Centre, Doctoral Training Centre, University of Oxford, OX1 3NP Oxford, United Kingdom
| | - Laura J Clark
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom
| | - Michael Culbert
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom
| | - Neil Dalchau
- Biological Computation, Microsoft Research Cambridge, CB1 2FB Cambridge, United Kingdom
| | - Megan Griffiths
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom
| | - Beatriz Jorrin
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom
| | - Ramakrishnan Karunakaran
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, NR4 7UH Norwich, United Kingdom
| | - Raphael Ledermann
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom
| | - Andrzej Tkacz
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom
| | - Isabel Webb
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom
| | - Euan K James
- Ecological Sciences, The James Hutton Institute, DD2 5DA Invergowrie, United Kingdom
| | - Philip S Poole
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom;
| | - Lindsay A Turnbull
- Department of Plant Sciences, University of Oxford, OX1 3RB Oxford, United Kingdom;
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Affiliation(s)
- L J Clark
- Fertilizer Investigations Research Branch, Soil and Water Conservation Research Division, Agricultural Research Service, U. S. Department of Agriculture, Beltsville, Md
| | - W L Hill
- Fertilizer Investigations Research Branch, Soil and Water Conservation Research Division, Agricultural Research Service, U. S. Department of Agriculture, Beltsville, Md
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Abstract
Introduction The incidence of deep neck space infection (DNSI) is rising and appears to be related to falling rates of tonsillectomy. The purpose of this study was to assess demographics of patients presenting with DNSI and the financial burden to the National Health Service (NHS). Methods Data were collected retrospectively on patients aged over 16 years admitted to NHS Greater Glasgow and Clyde with DNSI between 2012 and 2016. Demographics, aetiology and use of hospital resources were reviewed. The cost of hospital admissions was calculated using data from NHS Scotland's Information Services Division, the local diagnostics division and the British National Formulary. Results Seventy-four patients were admitted with DNSI during the study period. Forty (54%) were male. The mean age was 44.0 years (range: 16-86 years). The most frequent source of infection was the tonsil (n=30, 40.5%). The most common infective organism was Streptococcus constellatus (n=9, 12.2%). The mean length of stay was 11 days. Fifty-five patients (74.3%) required operative intervention. The mean cost of admission per patient was £5,700 (range: £332-£46,700). Conclusions This study highlights the high cost burden of DNSI to the NHS. The incidence of DNSI in Glasgow has risen over the study period; contributing factors may include the reduced tonsillectomy rate and a reduction in antibiotic prescribing. As the incidence of DNSI continues to rise, there will be an increase in cost to the NHS, which must be planned for.
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Clark LJ, Glennie L, Audrey S, Hickman M, Trotter CL. The health, social and educational needs of children who have survived meningitis and septicaemia: the parents' perspective. BMC Public Health 2013; 13:954. [PMID: 24112360 PMCID: PMC3852620 DOI: 10.1186/1471-2458-13-954] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 10/07/2013] [Indexed: 11/29/2022] Open
Abstract
Background Survivors of bacterial meningitis and septicaemia can experience a range of after-effects. There is little published research on the needs and provision of aftercare for children surviving bacterial meningitis and septicaemia. Methods Mixed methods study employing a survey and follow-up interviews with a sample of survey participants recruited from Meningitis Research Foundation’s member database and social media. Results Of 194 eligible survey respondents, 77% reported at least moderate short-term after-effects, and 57% a need for aftercare or support. Most parents reported that their child received a hearing test (98%) and follow-up appointment with a paediatrician (66%). Psychosocial after-effects were most common and the greatest need was for educational support. About half of participants felt their children’s needs for aftercare were met. We conducted interviews with 18 parents. Findings suggest access could be limited by: parents’ inability to navigate systems in place, child’s age, and delayed identification of sequelae. Parents felt a comprehensive explanation of possible after-effects on discharge from hospital was required, and found uncertain prognoses difficult. Good communication between professionals enabled a service tailored to the child’s needs. Conclusions Our study supports the NICE and SIGN guidelines and highlights areas for improvement in the aftercare of these children.
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Affiliation(s)
- Laura J Clark
- School of Social and Community Medicine, University of Bristol, Bristol, UK.
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Townsley RB, Florea CD, Clark LJ. The adult tracheostomy: a guide for the hospital at night doctor. Br J Hosp Med (Lond) 2012; 73:C152-5. [PMID: 23124199 DOI: 10.12968/hmed.2012.73.sup10.c152] [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: 11/11/2022]
Affiliation(s)
- R B Townsley
- Department of Ear, Nose and Throat Surgery, Royal Alexandra Hospital, Paisley, UK.
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Spender LC, O'Brien DI, Simpson D, Dutt D, Gregory CD, Allday MJ, Clark LJ, Inman GJ. TGF-beta induces apoptosis in human B cells by transcriptional regulation of BIK and BCL-XL. Cell Death Differ 2009; 16:593-602. [PMID: 19136942 PMCID: PMC2857326 DOI: 10.1038/cdd.2008.183] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
TGF-β potently induces apoptosis in Burkitt’s Lymphoma (BL) cell lines and in explanted primary human B lymphocytes. The physiological relevance and mechanism of TGF-β-mediated apoptosis induction in these cells remains to be determined. Here we demonstrate the requirement for TGF-β-mediated regulation of BIK and BCL-XL to activate an intrinsic apoptotic pathway in centroblastic BL cells. TGF-β directly induced transcription of BIK and a consensus Smad binding element identified in the BIK promoter recruits TGF-β-activated Smad transcription factor complexes in vivo. TGF-β also transcriptionally repressed expression of the apoptosis inhibitor BCL-XL. Inhibition of BCL-XL sensitised BL cells to TGF-β-induced apoptosis while overexpression of BCL-XL or suppression of BIK by shRNA, diminished TGF-β-induced apoptosis. BIK and BCL-XL were also identified as TGF-β target genes in purified normal human centroblast B cells and immunohistochemical analyses of tonsil tissue revealed widespread TGF-β receptor-regulated Smad activation and a focal pattern of BIK expression. Furthermore, using a selective inhibitor of the TGF-β receptor we provide evidence that autocrine TGF-β signaling through ALK5 contributes to the default apoptotic program in normal human centroblasts undergoing spontaneous apoptosis. Our data suggests that TGF-β may act as a physiological mediator of human germinal centre homeostasis via regulation of BIK and BCL-XL.
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Affiliation(s)
- L C Spender
- Growth Factor Signalling Laboratory, The Beatson Institute for Cancer Research, Garscube Estate, Switchback Road, Bearsden, Glasgow, UK.
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Cumberbatch GLA, Clark LJ, Neate B. Steroids for meningitis in the Emergency Department? Emerg Med J 2006; 23:161. [PMID: 16439762 PMCID: PMC2564053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
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10
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Abstract
Ectopic submandibular thyroid tissue is a rare entity and poses difficult diagnostic and management problems. The first case of ectopic submandibular thyroid with a normotopic multinodular goitre is presented
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Affiliation(s)
- A T M Mace
- Department of Otolaryngology, Royal Infirmary, Glasgow, UK.
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Abstract
OBJECTIVE To test the hypothesis that performance on a clock-drawing test in a mailed survey to an older cohort is associated with known and potential risk and protective factors for Alzheimer's disease. DESIGN The Leisure World Cohort Study is an ongoing study, begun in 1981, of nearly 14,000 older adults. In November 1992, the 8,406 living cohort members were mailed a follow-up questionnaire. SETTING Leisure World Laguna Hills, a southern California retirement community. PARTICIPANTS The study population is a predominantly white, well-educated, upper-middle-class community; approximately two-thirds are women. Data from 4,843 cohort members (mean age 80 years; range 52-101) were analyzed. MEASUREMENTS The questionnaire included a clock-drawing task: a predrawn circle 3 1/4 inches (8.3 cm) in diameter was provided with instructions "In the circle below, draw in the numbers as on a clock face. Make no erasures." Clocks were scored on 7 items: all numbers 1-12 present without adding extra or omitting numbers, sequencing of numbers, position of numbers, orientation of numbers to circle, consistent number style (either Arabic or Roman), tilt of numbers, and superfluous marks. A total clock score was calculated by summing the number of correct individual items (0-7). We also classified individuals as cognitively impaired by a previously suggested method: individuals were affected if they did not have three numbers drawn in the upper left quadrant of the clock face. RESULTS Ninety percent or more of the participants across all ages placed the numbers 1 to 12 on their clocks without omissions or additions; 35% completed the clock drawing without error. The mean total clock scores decreased with each successive 5-year age group in both men and women. Regression analysis indicated a significant effect for age (b = -0.15, P <.0001), education (b = 0.05, P =.0001), smoking (b = 0.13, P =.03), and female gender (b = -0.05, P =.05) and a marginally significant effect of nonrheumatoid arthritis (b = 0.05, P =.07) on total clock score. No other measured variable had a significant effect. Cognitively impaired individuals were more likely to be female and older. After adjusting for age and gender, they were also more likely to be hypertensive and to have taken blood pressure medication and less likely to be college graduates, have glaucoma or arthritis, and to have taken vitamin supplements. CONCLUSION The clock-drawing task is an appealing measure of cognitive function for large epidemiological studies because it is a simple, self-administered test that is easily adapted to mail surveys and correlates with more-detailed and more-time-consuming cognitive screens. Although it is relatively free of influence by language, cultural, or ethnic factors, our study shows that even in a highly educated population, clock drawing is influenced by educational level and other known risk factors for Alzheimer's disease. Thus a clock-drawing task may help predict cognitive frailty and future disability in older people. Such determination can direct high-risk individuals to earlier diagnosis, potential therapies, and better management.
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Affiliation(s)
- A Paganini-Hill
- Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA
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12
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Whalley WR, Lipiec J, Finch-Savage WE, Cope RE, Clark LJ, Rowse HR. Water stress can induce quiescence in newly-germinated onion (Allium cepa L.) seedlings. J Exp Bot 2001; 52:1129-1133. [PMID: 11432930 DOI: 10.1093/jexbot/52.358.1129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The effect of water stress on the early seedling growth of onions was studied by placing newly-germinated seedlings in vermiculite equilibrated at different water potentials. Roots and shoots elongated more at -0.29 than at -0.64 MPa, but did not elongate at -1.66 MPa. However, roots and shoots of seedlings that had been incubated in vermiculite at -1.66 MPa for up to 35 d resumed elongation when subsequently placed on wet filter boards. This suggests that water stress can induce quiescence in newly-germinated seedlings.
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Affiliation(s)
- W R Whalley
- Silsoe Research Institute, Wrest Park, Silsoe, Bedford MK45 4HS, UK.
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Clark LJ, Whalley WR, Barraclough PB. Partial mechanical impedance can increase the turgor of seedling pea roots. J Exp Bot 2001; 52:167-71. [PMID: 11181726] [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: 05/23/2023]
Abstract
Roots of 3-d-old pea seedlings (Pisum sativum L.) were mechanically impeded using a sand core apparatus, which allowed mechanical impedance to be varied independently of aeration and water status. Turgor of root cortical cells was then measured using a pressure probe. In seedlings grown in sand cores for 1 d, impedance had little effect on turgor, but in seedlings grown in the sand cores for 2 d, impedance increased turgor by 0.18 MPa in the apical 6 mm.
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Affiliation(s)
- L J Clark
- Biochemistry and Physiology Department, IACR-Rothamsted, Harpenden, Hertfordshire AL5 2JQ, UK.
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14
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Abstract
BACKGROUND Tamoxifen is an anti-estrogen used in the treatment of breast cancer and to reduce the incidence of breast cancer in high risk women. Although the brain is an estrogen target organ and several studies have found a beneficial effect of estrogen on cognitive function, the effect of tamoxifen on cognition has not been reported. Therefore, we initiated a follow-up study of women who had participated in a study of breast cancer to assess the effect of tamoxifen treatment on cognitive function. METHODS We recruited previously interviewed patients who were cases in a population-based case-control study of 2,653 women with primary breast cancer diagnosed between 1987 and 1996 at ages 55-72 years in Los Angeles County, California, USA. In November 1997, each case was mailed a follow-up questionnaire. Cognitive function was assessed by (1) clock drawing. (2) copying a box drawing, and (3) narrative writing to describe a pictured scene. Women reporting treatment with tamoxifen were categorized as standard-term users (4-5 years), short-term users (< 4 years) or long-term users (6 + years) and compared to never users. Tamoxifen users were also classified as past or current users. Differences in the mean cognitive test scores were tested after adjusting for age, age at diagnosis, stage of disease, radiation therapy, chemotherapy, race, education, marital status, previous use of oral contraceptives, type of menopause, age at last menstrual period, previous use of hormone replacement therapy, and depressive symptoms using analysis of covariance. All p-values for differences in the proportion of women who had errors on the tests are 2-sided and adjusted for age, stage of disease at diagnosis, and chemotherapy. FINDINGS Information from 1,163 women aged 57-75 years of age was analyzed; 710 had taken tamoxifen. There was little difference between women who had used tamoxifen for the standard five years and never users on the three cognitive tests. However, more women who had used tamoxifen for the standard term reported seeing their physician for memory problems than non-users (3.8% vs 1.5%, p = 0.04). This was especially true for current users of standard-term (8.0%, p = 0.003). Current users also had a significantly lower mean complexity score (p = 0.03) on the narrative writing task. No differences were seen between past users and non-users. INTERPRETATION Our study suggests that current use of tamoxifen may adversely effect cognition. Further study of tamoxifen and cognition is needed so that healthy women considering tamoxifen for the primary prevention of breast cancer have comprehensive information about the side effects of the treatment.
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Affiliation(s)
- A Paganini-Hill
- Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, USA.
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Clark LJ, Watson J, Cobbe SM, Reeve W, Swann IJ, Macfarlane PW. CPR '98: a practical multimedia computer-based guide to cardiopulmonary resuscitation for medical students. Resuscitation 2000; 44:109-17. [PMID: 10767498 DOI: 10.1016/s0300-9572(99)00171-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [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: 11/20/2022]
Abstract
This paper describes an initiative to build a multimedia computer-based teaching package for cardiopulmonary resuscitation. The project resulted from a perceived gap in the undergraduate medical curriculum allied to concern from medical students. The software application was designed to be networked and used as an adjunct to taught life support courses for undergraduate medical students. The package comprises tutorials and test questions in basic and advanced life support. It incorporates sound, video, graphics and animation to illustrate the techniques involved and is distributed on CD ROM for the PC. The content is based on the 'Advanced Life Support Manual', produced by the Resuscitation Council (UK) and incorporates all changes to the guidelines made during 1997 and 1998. The basic life support section has been networked locally, and has been tested on more than 60 third year medical students attending a local basic life support course. It was found that students who used the package performed significantly better in theoretical assessments than those who did not.
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Affiliation(s)
- L J Clark
- The Microcomputer Cluster, Level 1, Glasgow Royal Infirmary, Glasgow, UK
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Abstract
BACKGROUND Tamoxifen is an oral anti-estrogen used in the treatment of breast cancer and recently approved to reduce the incidence of breast cancer in high risk women. As a large clinical trial of tamoxifen has reported an increased risk of cataract, we conducted a study of women with breast cancer to evaluate the association of tamoxifen with cataracts and other eye problems. METHODS We attempted to recruit previously interviewed patients who were cases in a population-based case-control study of 2653 women with primary breast cancer diagnosed between 1987 and 1996 at ages 55-72 years in Los Angeles County, California, USA. In November 1997, each case was mailed a questionnaire to ascertain self-reported incidence of eye diseases and Amsler grid test scores. Information from 1297 women aged 57-75 years of age was analyzed. Women reporting treatment with tamoxifen were categorized as standard-term users (4-5 years), short-term users (<4 years), or long-term users (6+ years) and compared to non-users. All p-values, relative risks, and confidence intervals for differences in eye problems and grid test results are adjusted for age and stage of disease at diagnosis. FINDINGS Standard-term and long-term users of tamoxifen more frequently reported developing cataracts than non-users (18.2%, 21.4% vs. 14.8%). The relative risk was 1.40 (95% confidence interval 0.94-2.10) for standard-term users and 1.70 (1.11-2.59) for long-term users. Tamoxifen use was unrelated to frequency of glaucoma or macular degeneration or to Amsler grid test results. INTERPRETATION Our study suggests that five or more years of tamoxifen use increases risk of cataracts. Healthy women considering tamoxifen use to reduce risk of breast cancer should be advised of the possibility of cataract development. Women choosing such therapy should be diligent about receiving regular ocular exams.
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Affiliation(s)
- A Paganini-Hill
- Department of Preventive Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, USA.
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Bryce SD, Forsyth NR, Fitzsimmons SA, Clark LJ, Bertram MJ, Cuthbert AP, Newbold RF, Pereira-Smith OM, Parkinson EK. Genetic and functional analyses exclude mortality factor 4 (MORF4) as a keratinocyte senescence gene. Cancer Res 1999; 59:2038-40. [PMID: 10232582] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
Approximately 50% of immortal human keratinocyte lines show loss of heterozygosity of chromosome region 4q33-q34, and the reintroduction of chromosome 4 into one such line, BICR 6, causes proliferation arrest and features of replicative senescence. Recently, a candidate gene, mortality factor 4 (MORF4), was identified in this region and sequenced in 21 immortal keratinocyte lines. There were no mutations or deletions, and two of the seven lines that showed loss of heterozygosity at 4q33-q34 were heterozygous for MORF4 itself. Furthermore, the transfer of a chromosomal segment containing the entire MORF4 gene did not mimic the senescence effect of chromosome 4 in BICR 6. These results suggest that the inactivation of MORF4 is not required for human keratinocyte immortality.
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Affiliation(s)
- S D Bryce
- Beatson Institute for Cancer Research, CRC Beatson Laboratories, Bearsden, Glasgow, United Kingdom
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18
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Bertram MJ, Bérubé NG, Hang-Swanson X, Ran Q, Leung JK, Bryce S, Spurgers K, Bick RJ, Baldini A, Ning Y, Clark LJ, Parkinson EK, Barrett JC, Smith JR, Pereira-Smith OM. Identification of a gene that reverses the immortal phenotype of a subset of cells and is a member of a novel family of transcription factor-like genes. Mol Cell Biol 1999; 19:1479-85. [PMID: 9891081 PMCID: PMC116076 DOI: 10.1128/mcb.19.2.1479] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.5] [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] [Received: 06/24/1998] [Accepted: 10/30/1998] [Indexed: 11/20/2022] Open
Abstract
Based on the dominance of cellular senescence over immortality, immortal human cell lines have been assigned to four complementation groups for indefinite division. Human chromosomes carrying senescence genes have been identified, including chromosome 4. We report the cloning and identification of a gene, mortality factor 4 (MORF 4), which induces a senescent-like phenotype in immortal cell lines assigned to complementation group B with concomitant changes in two markers for senescence. MORF 4 is a member of a novel family of genes with transcription factor-like motifs. We present here the sequences of the seven family members, their chromosomal locations, and a partial characterization of the three members that are expressed. Elucidation of the mechanism of action of these genes should enhance our understanding of growth regulation and cellular aging.
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Affiliation(s)
- M J Bertram
- Roy M. and Phyllis Gough Huffington Center on Aging, Baylor College of Medicine, Houston, Texas 77030, USA.
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19
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Loughran O, Clark LJ, Bond J, Baker A, Berry IJ, Edington KG, Ly IS, Simmons R, Haw R, Black DM, Newbold RF, Parkinson EK. Evidence for the inactivation of multiple replicative lifespan genes in immortal human squamous cell carcinoma keratinocytes. Oncogene 1997; 14:1955-64. [PMID: 9150362 DOI: 10.1038/sj.onc.1201028] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.0] [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: 02/04/2023]
Abstract
Human keratinocyte immortality is genetically recessive to the normal phenotype of limited replicative lifespan and appears to require the dysfunction of p53 and the cyclin D-Cdk inhibitor p16. In order to test for the inactivation of other candidate replicative lifespan genes in the immortal cells of human tumors, we developed a series of mortal and immortal keratinocyte cultures derived from neoplastic lesions of the head and neck which were amenable to molecular genetic analysis by the loss of heterozygosity (LOH) technique. The results indicate that keratinocyte immortalization in head and neck squamous cell carcinoma (SCC-HN) development involves the inactivation of at least two further pathways to senescence and four in all. Chromosomes 1, 4 and 7 carry genes representing immortality complementation groups C, B and D respectively and immortal keratinocytes showed LOH at either 4q32-q34 between D4S1554 and D4S171 (group B) or 7q31 (group D) but never 1q25 (group C). These results tentatively suggest that the genes responsible for the immortality complementation groups encode proteins on the same pathway to senescence. In addition, all of the immortal keratinocyte lines possessed high levels of telomerase activity and a suppressor of telomerase activity has been mapped to the short arm of chromosome 3p. Five out of eight lines showed LOH at 3p21.2-p21.3, a region which may carry a gene capable of suppressing SCC-HN telomerase. However, alternative mechanisms of telomerase reactivation were also suggested by our results. None of the above genetic alterations were seen in seven senescent neoplastic keratinocyte cultures. Other loci harbouring antiproliferative genes implicated in replicative lifespan showed few or no alterations and any alterations seen were additional to those described above.
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MESH Headings
- Carcinoma, Squamous Cell/genetics
- Carcinoma, Squamous Cell/pathology
- Cell Survival
- Cellular Senescence
- Chromosome Deletion
- Chromosome Mapping
- Chromosomes, Human, Pair 1
- Chromosomes, Human, Pair 3
- Chromosomes, Human, Pair 4
- Chromosomes, Human, Pair 7
- Genes, Suppressor
- Genetic Complementation Test
- Genetic Markers
- Head and Neck Neoplasms/genetics
- Head and Neck Neoplasms/pathology
- Humans
- Keratinocytes/pathology
- Telomerase/biosynthesis
- Telomerase/genetics
- Tumor Cells, Cultured
- X Chromosome
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Affiliation(s)
- O Loughran
- CRC Beatson Laboratories, Beatson Institute for Cancer Research, Garscube Estate, Bearsden, Glasgow, Scotland
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20
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Loughran O, Edington KG, Berry IJ, Clark LJ, Parkinson EK. Loss of heterozygosity of chromosome 9p21 is associated with the immortal phenotype of neoplastic human head and neck keratinocytes. Cancer Res 1994; 54:5045-9. [PMID: 7923114] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Human chromosomes 1,4,6, and 9 harbor genes which induce cellular senescence in vitro but a role for their inactivation in human tumors is not established. To investigate this we searched for loss of heterozygosity (LOH) on these chromosomes in keratinocyte cultures obtained from different stages of human squamous cell carcinoma progression. There was consistent LOH between markers D9S171 and D9S157 in 9 of 9 (100%) informative immortal cultures and in one line which entered crisis, but 0 of 7 informative senescent cultures showed LOH. These results suggest that inactivation of a gene at 9p21 is important but insufficient for human squamous cell carcinoma keratinocyte immortalization.
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Affiliation(s)
- O Loughran
- CRC Beatson Laboratories, Bearsden, Glasgow, Scotland
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21
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Abstract
Around 60% of oral squamous cell carcinomas (SCCs) have been shown to harbour p53 mutations, and other studies have demonstrated mutant p53 genes in normal and dysplastic squamous epithelium adjacent to these SCCs. In line with these earlier studies we show here that DOK, a keratinocyte cell line derived from a dysplasia, displays elevated levels of p53 protein and harbours a 12 bp in-frame deletion of the p53 gene spanning codons 188-191. In contrast, the coding region of the p53 gene was normal in a series of six benign recurrent laryngeal papillomas and a series of four premalignant oral erythroplakia biopsies and their cell cultures. All but one of these lesions were free of malignancy at the time of biopsy, in contrast to the premalignant lesions studied by previous investigators, but keratinocytes cultured from these lesions all displayed a partially transformed phenotype that was less pronounced than that of DOK. Since three out of four of the erythroplakia patients developed SCC within 1 year of biopsy, these lesions were by definition premalignant. The availability of strains of partially transformed keratinocytes from premalignant erythroplakias which possess normal p53 genes should enable us to test the role of mutant p53 in the progression of erythroplakia to SCC. The premalignant tissues and cultures were also tested for the presence of human papillomavirus (HPV), which is known to inactivate p53 function in some cases. Only the benign papillomas were shown to contain high levels of either HPV 6 or HPV 11 E6 DNA, but not both, and none of the samples contained detectable levels of HPV 16, HPV 18 or HPV 33 E6 DNA or L1 DNA of several other HPV types. There was therefore no evidence to suggest that p53 was being inactivated by a highly oncogenic HPV in these samples.
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Affiliation(s)
- J E Burns
- CRC Laboratories, Garscube Estate, Bearsden, Glasgow, UK
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22
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Burns JE, McFarlane R, Clark LJ, Mitchell R, Robertson G, Soutar D, Parkinson EK. Maintenance of identical p53 mutations throughout progression of squamous cell carcinomas of the tongue. Eur J Cancer B Oral Oncol 1994; 30B:335-7. [PMID: 7703803 DOI: 10.1016/0964-1955(94)90035-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The occurrence of mutations within the coding sequence of the p53 tumour suppressor gene is now well documented for squamous cell carcinomas of the head and neck region. However, evidence that these mutations are required for the maintenance and progression of squamous tumours is still formally lacking. To test this we have examined whether p53 mutations detected in primary squamous cell carcinomas of the tongue are also detected in the corresponding lymph node metastases. Three different p53 mutations were detected in each of three primary tongue squamous cell carcinomas (SCC), and in each case the same mutation was detected in a lymph node metastasis excised from the same patient. Although the sample number is small, the chance of obtaining the same p53 mutation independently in both the primary and metastatic tumour of each patient is at least 10(-4), therefore the results indicate that keratinocytes harbouring these p53 mutations possess a selective advantage throughout SCC progression.
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Affiliation(s)
- J E Burns
- CRC Beatson Laboratories, Bearsden, Glasgow, U.K
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23
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Clark LJ, Edington K, Swan IR, McLay KA, Newlands WJ, Wills LC, Young HA, Johnston PW, Mitchell R, Robertson G. The absence of Harvey ras mutations during development and progression of squamous cell carcinomas of the head and neck. Br J Cancer 1993; 68:617-20. [PMID: 8353052 PMCID: PMC1968389 DOI: 10.1038/bjc.1993.396] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
We have examined the incidence of Harvey ras mutations in human squamous cell carcinomas (SCC) of the upper aerodigestive tract using the polymerase chain reaction (PCR) followed by direct sequencing. No mutations were detected at codons 12, 13, 59 or 61 of this gene in any of six papillomas, five erythroplakias, 56 squamous cell carcinomas, and 16 SCC cell lines. Some of the SCC were lymph node metastases (three) or tumours which had recurred following radiotherapy (seven). We conclude that Harvey ras mutations are not a common event in the pathogenesis or recurrence of SCCs from Caucasian subjects, in contrast to the situation with Indian populations (Saranath et al., 1991).
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Affiliation(s)
- L J Clark
- Beatson Institute for Cancer Research, CRC Beatson Laboratories, Glasgow, U.K
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24
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Abstract
Pigmented villonodular synovitis commonly occurs in synovial joints of the appendicular skeleton, but rarely affects the synovial joints of the spine. It has both neoplastic and benign features, and the etiology is thought to be posttraumatic. The case of a young man presenting with paraparesis and a large thoracic lesion is reported.
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Affiliation(s)
- L J Clark
- Department of Neurosurgery, Toledo Hospital, Ohio
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25
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Burns JE, Baird MC, Clark LJ, Burns PA, Edington K, Chapman C, Mitchell R, Robertson G, Soutar D, Parkinson EK. Gene mutations and increased levels of p53 protein in human squamous cell carcinomas and their cell lines. Br J Cancer 1993; 67:1274-84. [PMID: 8390283 PMCID: PMC1968513 DOI: 10.1038/bjc.1993.238] [Citation(s) in RCA: 98] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Using immunocytochemical and Western blotting techniques we have demonstrated the presence of abnormally high levels of p53 protein in 8/24 (33%) of human squamous cell carcinomas (SCC) and 9/18 (50%) of SCC cell lines. There was a correlation between the immunocytochemical results obtained with eight SCC samples and their corresponding cell lines. Direct sequencing of PCR-amplified, reverse transcribed, p53 mRNA confirmed the expression of point mutations in six of the positive cell lines and detected in-frame deletions in two others. We also detected two stop mutations and three out-of-frame deletions in five lines which did not express elevated levels of p53 protein. Several of the mutations found in SCC of the tongue (3/7) were in a region (codons 144-166) previously identified as being a p53 mutational hot spot in non-small cell lung tumours (Mitsudomi et al., 1992). In 11/13 cases only the mutant alleles were expressed suggesting loss or reduced expression of the wild type alleles in these cases. Six of the mutations were also detected in the SCCs from which the lines were derived, strongly suggesting that the mutations occurred, and were selected, in vivo. The 12th mutation GTG-->GGG (valine-->glycine) at codon 216 was expressed in line SCC-12 clone B along with an apparently normal p53 allele and is to our knowledge a novel mutation. Line BICR-19 also expressed a normal p53 allele in addition to one where exon 10 was deleted. Additionally 15 of the SCC lines (including all of those which did not show elevated p53 protein levels) were screened for the presence of human papillomavirus types 16 and 18 and were found to be negative. These results are discussed in relation to the pathogenesis of SCC and the immortalisation of human keratinocytes in vitro.
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Affiliation(s)
- J E Burns
- Cancer Research Campaign, Beatson Institute for Cancer Research, Garscube Estate, Bearsden, Glasgow, UK
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26
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Abstract
Using immunocytochemical techniques, recurrent laryngeal papillomas from six adult patients were studied. The p53 tumour suppressor gene protein was detected in the basal epithelial cells in papillomas from all six patients. None was detected in normal epithelium. Elevated levels of p53 protein are usually indicative of its inactivation either by point mutation or by complexing with tumour virus proteins.
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Affiliation(s)
- L J Clark
- Beatson Institute for Cancer Research, Glasgow, UK
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27
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Affiliation(s)
- L J Clark
- Beatson Institute for Cancer Research, Glasgow, UK
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28
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Abstract
Relapsing polychondritis is a rare disease which often presents firstly to ear, nose and throat (ENT) departments. Its complications, respiratory, cardiovascular, renal and neurological are life-threatening; thus it is important to recognize the disease and its complications early. Treatment for relapsing polychondritis may have serious side-effects which should be taken into account when managing these patients. We report two young patients with relapsing polychondritis and their treatments; both had severe tracheal stenosis responding in one case to pharmacological and in the other to surgical intervention.
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Affiliation(s)
- L J Clark
- Beatson Institute for Cancer Research, Wolfson Laboratory for Molecular Pathology, Bearsden, Glasgow
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29
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30
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Clark LJ. Concurrent care denials: clouding the horizon. Internist 1991; 32:34, 36. [PMID: 10111366] [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: 02/11/2023]
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31
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Abstract
Carcinoma of the middle ear is a difficult tumour to treat. We present ten cases and discuss staging of these tumours. Our results would suggest that a revised staging system may allow better identification of patients that would benefit from surgery whilst sparing some multilating surgery that offers little to improve their quality or quantity of life.
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Affiliation(s)
- L J Clark
- Beatson Institute for Cancer Research, Wolfson Laboratory for Molecular Biology, Bearsden, Glasgow
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32
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Abstract
We present a prospective controlled trial, comparing methods of analgesia for the relief of discomfort on removing nasal packing, including a general discussion on the considerations for, and methods of, nasal tamponade. On the basis that nasal packing is likely to continue to be used frequently, nitrous oxide (as Entonox) is advocated as a safe and relatively cheap means of pain relief with a statistically significant advantage over papaveretum.
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Affiliation(s)
- M R Laing
- Department of Otolaryngology, Royal Infirmary, Aberdeen, UK
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33
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Affiliation(s)
- A Macneil
- Department of Anaesthesia, Aberdeen Royal Infirmary, United Kingdom
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34
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Abstract
Commercial non-lubricated latex condoms were unpackaged and exposed in an environmental chamber to ozone levels (0.3 ppm) commonly present in urban smog conditions. Deterioration was observed by scanning electron microscopy after 18 hours exposure. Loss of mechanical strength was quantitated by measurement of the air pressures necessary to burst the condom and volumes at burst. After 24 hours exposure to ozone the latex surface was covered with craters and after 48 hours the pressure required to burst the condom was 44% that of control samples. Data suggest the need for study of the effectiveness of lubrication and packaging in protecting condoms from environmental factors which may accelerate deterioration.
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Affiliation(s)
- L J Clark
- Department of Microbiology, University of Southern California School of Medicine, Los Angeles 90033
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35
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Clark LJ. Neurosurgeons' role in organ procurement. J Neurosurg 1987; 66:947-8. [PMID: 3572527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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36
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Clark LJ, Chan LS, Powars DR, Baker RF. Negative charge distribution and density on the surface of oxygenated normal and sickle red cells. Blood 1981; 57:675-8. [PMID: 7470618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Negative charges on the external surface of red cells were visualized by colloidal iron hydroxide labelling of 50% of the membrane area after osmotic hemolysis and glutaraldehyde fixation. Counts were made over randomly selected areas on electron micrographs at 350,000 x magnification. Statistical analyses showed that at the 95% level of confidence there was no significant difference between oxygenated normal (AA) and sickle (SS) cells in either the distribution or the density of negative charges.
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37
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Clark LJ, Field MJ, Koontz TL, Koontz VL. The impact of Hill-Burton: an analysis of hospital bed and physician distribution in the United States, 1950-1970. Med Care 1980; 18:532-50. [PMID: 7401707 DOI: 10.1097/00005650-198005000-00006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The Hospital Survey and Construction Act of 1946, commonly known as the Hill-Burton Act, was intended to improve the supply, distribution and quality of general hospital beds across the United States. Some also saw the program as a means of affecting the supply and distribution of physicians. The strategy used here for evaluating the Hill-Burton program derives in part from the assumptions about health resources supplies on which Hill-Burton policy was found and in part from a model of socioeconomic convergence developed in public policy research on the American states. Major conclusions include 1) Hill-Burton had a major redistributive impact on state bed supplies; 2) physician redistribution lagged far behind progress in bed redistribution; and 3) interstate distribution of physicians appears to have been unaffected by Hill-Burton-associated bed redistribution, a finding contrary to other work in this area.
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38
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Majak W, Udenberg T, Clark LJ, McLean A. Toxicity of Saskatoon serviceberry to cattle. Can Vet J 1980; 21:74-6. [PMID: 6244889 PMCID: PMC1789689] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Saskatoon serviceberry (Amelanchier alnifolia) twigs were administered to cattle in feed rations and by intraruminal dosing to determine the toxicity of the cyanogenic shrub. When chopped twigs were fed as 75% of the diet, cattle exhibited restlessness, shivering, loss of weight, scours and shortness of breath. Low level dosing experiments indicated a rapid turnover of hydrogen cyanide in the rumen. When potential doses were increased to 5 mg hydrogen cyanide/kg (body weight) progressive stages of poisoning developed rapidly, rumen hydrogen cyanide levels were elevated for at least three hours and the increase in heart rate correlated with the rise in blood hydrogen cyanide concentration.
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39
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40
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Clark LJ. Honolulu Invites You to MLA 79. Bull Med Libr Assoc 1979; 67:47-50. [PMID: 16017755 PMCID: PMC226882] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Honolulu is the host city for the MLA Annual Meeting in 1979. The attractions of Honolulu and Hawaii are recommended to members.
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Affiliation(s)
- L J Clark
- Kaiser Medical Center, Honolulu, Hawaii
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41
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Caro JH, Batson HE, Clark LJ. Composition and Fertilizer Potential of Precipitator Dusts from Phosphate Smelting Furnaces. J AOAC Int 1958. [DOI: 10.1093/jaoac/41.3.649] [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: 11/13/2022]
Affiliation(s)
- J H Caro
- Fertilizer Investigations Research Branch, Soil and Water Conservation Research Division, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Md
| | - H E Batson
- Fertilizer Investigations Research Branch, Soil and Water Conservation Research Division, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Md
| | - L J Clark
- Fertilizer Investigations Research Branch, Soil and Water Conservation Research Division, Agricultural Research Service, U.S. Department of Agriculture, Beltsville, Md
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