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Davies DJ, McLean PF, Kemp PR, Liddle AD, Morrell MJ, Halse O, Martin NM, Sam AH. Assessment of factual recall and higher-order cognitive domains in an open-book medical school examination. Adv Health Sci Educ Theory Pract 2022; 27:147-165. [PMID: 34687383 PMCID: PMC8536902 DOI: 10.1007/s10459-021-10076-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Accepted: 09/19/2021] [Indexed: 06/04/2023]
Abstract
Open-book examinations (OBEs) will likely become increasingly important assessment tools. We investigated how access to open-book resources affected questions testing factual recall, which might be easy to look-up, versus questions testing higher-order cognitive domains. Few studies have investigated OBEs using modern Internet resources or as summative assessments. We compared performance on an examination conducted as a traditional closed-book exam (CBE) in 2019 (N = 320) and a remote OBE with free access to Internet resources in 2020 (N = 337) due to COVID-19. This summative, end-of-year assessment focused on basic science for second-year medical students. We categorized questions by Bloom's taxonomy ('Remember', versus 'Understand/Apply'). We predicted higher performance on the OBE, driven by higher performance on 'Remember' questions. We used an item-centric analysis by using performance per item over all examinees as the outcome variable in logistic regression, with terms 'Open-Book, 'Bloom Category' and their interaction. Performance was higher on OBE questions than CBE questions (OR 2.2, 95% CI: 2.14-2.39), and higher on 'Remember' than 'Understand/Apply' questions (OR 1.13, 95% CI: 1.09-1.19). The difference in performance between 'Remember' and 'Understand/Apply' questions was greater in the OBE than the CBE ('Open-Book' * 'Bloom Category' interaction: OR 1.2, 95% CI: 1.19-1.37). Access to open-book resources had a greater effect on performance on factual recall questions than higher-order questions, though performance was higher in the OBE overall. OBE design must consider how searching for information affects performance, particularly on questions measuring different domains of knowledge.
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Affiliation(s)
- D J Davies
- Imperial College School of Medicine, Imperial College London, London, England.
| | - P F McLean
- Imperial College School of Medicine, Imperial College London, London, England
| | - P R Kemp
- Imperial College School of Medicine, Imperial College London, London, England
- National Heart and Lung Institute, Imperial College London, London, England
| | - A D Liddle
- Imperial College School of Medicine, Imperial College London, London, England
| | - M J Morrell
- Imperial College School of Medicine, Imperial College London, London, England
- National Heart and Lung Institute, Imperial College London, London, England
| | - O Halse
- Imperial College School of Medicine, Imperial College London, London, England
| | - N M Martin
- Imperial College School of Medicine, Imperial College London, London, England
| | - A H Sam
- Imperial College School of Medicine, Imperial College London, London, England
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Patel MS, Donaldson AV, Lewis A, Natanek SA, Lee JY, Andersson YM, Haji G, Jackson SG, Bolognese BJ, Foley JP, Podolin PL, Bruijnzeel PLB, Hart N, Hopkinson NS, Man WDC, Kemp PR, Polkey MI. Klotho and smoking--An interplay influencing the skeletal muscle function deficits that occur in COPD. Respir Med 2016; 113:50-6. [PMID: 27021580 DOI: 10.1016/j.rmed.2016.02.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 02/05/2016] [Accepted: 02/11/2016] [Indexed: 02/08/2023]
Abstract
BACKGROUND Klotho is an 'anti-ageing' hormone and transmembrane protein; Klotho deficient mice develop a similar ageing phenotype to smokers including emphysema and muscle wasting. The objective of this study was to evaluate skeletal muscle and circulating Klotho protein in smokers and COPD patients and to relate Klotho levels to relevant skeletal muscle parameters. We sought to validate our findings by undertaking complimentary murine studies. METHODS Fat free mass, quadriceps strength and spirometry were measured in 87 participants (61 COPD, 13 'healthy smokers' and 13 never smoking controls) in whom serum and quadriceps Klotho protein levels were also measured. Immunohistochemistry was performed to demonstrate the location of Klotho protein in human skeletal muscle and in mouse skeletal muscle in which regeneration was occurring following injury induced by electroporation. In a separate study, gastrocnemius Klotho protein was measured in mice exposed to 77 weeks of smoke or sham air. RESULTS Quadriceps Klotho levels were lower in those currently smoking (p = 0.01), irrespective of spirometry, but were not lower in patients with COPD. A regression analysis identified current smoking status as the only independent variable associated with human quadriceps Klotho levels, an observation supported by the finding that smoke exposed mice had lower gastrocnemius Klotho levels than sham exposed mice (p = 0.005). Quadriceps Klotho levels related to local oxidative stress but were paradoxically higher in patients with established muscle wasting or weakness; the unexpected relationship with low fat free mass was the only independent association. Within locomotor muscle, Klotho localized to the plasma membrane and to centralized nuclei in humans and in mice with induced muscle damage. Serum Klotho had an independent association with quadriceps strength but did not relate to quadriceps Klotho levels or to spirometric parameters. CONCLUSIONS Klotho is expressed in skeletal muscle and levels are reduced by smoking. Despite this, quadriceps Klotho protein expression in those with established disease appears complex as levels were paradoxically elevated in COPD patients with established muscle wasting. Whilst serum Klotho levels were not reduced in smokers or COPD patients and were not associated with quadriceps Klotho protein, they did relate to quadriceps strength.
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Affiliation(s)
- M S Patel
- NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, UK; Imperial College London, UK
| | - A V Donaldson
- NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, UK; Imperial College London, UK
| | | | - S A Natanek
- NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, UK; Imperial College London, UK
| | | | | | - G Haji
- NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, UK; Imperial College London, UK
| | | | - B J Bolognese
- Respiratory Therapeutic Area, GlaxoSmithKline, King of Prussia, PA, USA
| | - J P Foley
- Respiratory Therapeutic Area, GlaxoSmithKline, King of Prussia, PA, USA
| | - P L Podolin
- Respiratory Therapeutic Area, GlaxoSmithKline, King of Prussia, PA, USA
| | | | - N Hart
- NIHR Comprehensive Biomedical Research Centre, Guy's & St Thomas' NHS Foundation Trust and King's College London, London, UK
| | - N S Hopkinson
- NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, UK; Imperial College London, UK
| | - W D-C Man
- NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, UK; Imperial College London, UK
| | | | - M I Polkey
- NIHR Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, UK; Imperial College London, UK.
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Paul RG, Polkey MI, Kemp PR, Griffiths MJD. S116 GDF-15, the miR-542 cluster and miR-422a are associated with muscle wasting in Intensive Care Unit Acquired Paresis. Thorax 2015. [DOI: 10.1136/thoraxjnl-2015-207770.122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Bloch SAA, Lee JY, Syburra T, Rosendahl U, Griffiths MJD, Kemp PR, Polkey MI. Increased expression of GDF-15 may mediate ICU-acquired weakness by down-regulating muscle microRNAs. Thorax 2014; 70:219-28. [PMID: 25516419 PMCID: PMC4345798 DOI: 10.1136/thoraxjnl-2014-206225] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [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] [Indexed: 12/31/2022]
Abstract
Rationale The molecular mechanisms underlying the muscle atrophy of intensive care unit-acquired weakness (ICUAW) are poorly understood. We hypothesised that increased circulating and muscle growth and differentiation factor-15 (GDF-15) causes atrophy in ICUAW by changing expression of key microRNAs. Objectives To investigate GDF-15 and microRNA expression in patients with ICUAW and to elucidate possible mechanisms by which they cause muscle atrophy in vivo and in vitro. Methods In an observational study, 20 patients with ICUAW and seven elective surgical patients (controls) underwent rectus femoris muscle biopsy and blood sampling. mRNA and microRNA expression of target genes were examined in muscle specimens and GDF-15 protein concentration quantified in plasma. The effects of GDF-15 on C2C12 myotubes in vitro were examined. Measurements and main results Compared with controls, GDF-15 protein was elevated in plasma (median 7239 vs 2454 pg/mL, p=0.001) and GDF-15 mRNA in the muscle (median twofold increase p=0.006) of patients with ICUAW. The expression of microRNAs involved in muscle homeostasis was significantly lower in the muscle of patients with ICUAW. GDF-15 treatment of C2C12 myotubes significantly elevated expression of muscle atrophy-related genes and down-regulated the expression of muscle microRNAs. miR-181a suppressed transforming growth factor-β (TGF-β) responses in C2C12 cells, suggesting increased sensitivity to TGF-β in ICUAW muscle. Consistent with this suggestion, nuclear phospho-small mothers against decapentaplegic (SMAD) 2/3 was increased in ICUAW muscle. Conclusions GDF-15 may increase sensitivity to TGF-β signalling by suppressing the expression of muscle microRNAs, thereby promoting muscle atrophy in ICUAW. This study identifies both GDF-15 and associated microRNA as potential therapeutic targets.
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Affiliation(s)
- S A A Bloch
- Molecular Medicine, National Heart and Lung Institute, Imperial College, London, UK
| | - J Y Lee
- Molecular Medicine, National Heart and Lung Institute, Imperial College, London, UK
| | - T Syburra
- National Institute for Health Research Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, London, UK
| | - U Rosendahl
- National Institute for Health Research Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, London, UK
| | - M J D Griffiths
- National Institute for Health Research Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, London, UK Leukocyte Biology, National Heart and Lung Institute, Imperial College, London, UK
| | - P R Kemp
- Molecular Medicine, National Heart and Lung Institute, Imperial College, London, UK
| | - M I Polkey
- National Institute for Health Research Respiratory Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust and Imperial College, London, UK
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Bloch SAA, Kemp PR, Griffiths MJD, Polkey MI. S55 Mir-181: a potential biomarker of acute muscle wasting? Thorax 2013. [DOI: 10.1136/thoraxjnl-2013-204457.62] [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: 11/04/2022]
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Patel MS, Donaldson AV, Natanek SA, Bruijnzeel PLB, Hopkinson NS, Man WDC, Kemp PR, Polkey MI. S51 Klotho is associated with skeletal muscle dysfunction and oxidative stress in COPD. Thorax 2013. [DOI: 10.1136/thoraxjnl-2013-204457.58] [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: 11/03/2022]
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Donaldson AVJ, Tanner RJ, Davey CA, Hopkinson N, Man WDC, Kemp PR, Polkey MI. S52 MiR-181 increases in the quadriceps muscle of COPD patients after an acute bout of exercise: Abstract S52 Table 1. Thorax 2013. [DOI: 10.1136/thoraxjnl-2013-204457.59] [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: 11/04/2022]
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Maddocks M, Shrikrishna D, Vitoriano S, Tanner RJ, Natanek SA, Hart N, Kemp PR, Moxham J, Polkey MI, Hopkinson NS. P78 Physical Inactivity is Associated with Mid-Thigh Intramuscular Fat in Patients with COPD. Thorax 2012. [DOI: 10.1136/thoraxjnl-2012-202678.320] [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: 11/04/2022]
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Shrikrishna D, Tanner RJ, Lee JY, Natanek SA, Lewis A, Murphy PB, Hart N, Moxham J, Montgomery H, Kemp PR, Polkey MI, Hopkinson NS. S48 The Effect of Angiotensin-Converting Enzyme Inhibition on Skeletal Muscle Dysfunction in Chronic Obstructive Pulmonary Disease: A Randomised Controlled Trial. Thorax 2012. [DOI: 10.1136/thoraxjnl-2012-202678.054] [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: 11/03/2022]
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Bloch SAA, Lee JY, Wort SJ, Polkey MI, Kemp PR, Griffiths MJD. S73 Circulating Regulators of Acute Muscle Wasting in the Critically Ill: GDF-15 a Potential Novel Driver of Acute Muscle Wasting. Thorax 2012. [DOI: 10.1136/thoraxjnl-2012-202678.079] [Citation(s) in RCA: 3] [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: 11/04/2022]
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Natanek SA, Gosker HR, Slot I, Marsh GS, Langen RCJ, Hopkinson NS, Man WDC, Moxham J, Kemp PR, Schols AMWJ, Polkey MI. P144 Muscle fibre atrophy and aerobic to anaerobic fibre type shift in the quadriceps in COPD. Thorax 2010. [DOI: 10.1136/thx.2010.150987.45] [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: 11/03/2022]
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Natanek SA, Langen RCJ, Gosker HR, Marsh GS, Slot I, Hopkinson NS, Man WDC, Kemp PR, Moxham J, Schols AMWJ, Polkey MI. P143 NF-kappa B (NF- B) and activator protein-1 (AP-1) DNA binding in the quadriceps of COPD patients. Thorax 2010. [DOI: 10.1136/thx.2010.150987.44] [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: 11/03/2022]
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Abstract
1. The unusual kinetics of human ether-à-go-go-related gene (HERG) K(+) channels are consistent with a role in the suppression of arrhythmias initiated by premature beats. Action potential clamp protocols were used to investigate the effect of premature stimulation on HERG K(+) channels, transfected in Chinese hamster ovary cells, at 37 degrees C. 2. HERG K(+) channel currents peaked during the terminal repolarization phase of normally paced action potential waveforms. However, the magnitude of the current and the time point at which conductance was maximal depended on the type of action potential waveform used (epicardial, endocardial, Purkinje fibre or atrial). 3. HERG K(+) channel currents recorded during premature action potentials consisted of an early transient outward current followed by a sustained outward current. The magnitude of the transient current component showed a biphasic dependence on the coupling interval between the normally paced and premature action potentials and was maximal at a coupling interval equivalent to 90 % repolarization (APD(90)) for ventricular action potentials. The largest transient current response occurred at shorter coupling intervals for Purkinje fibre (APD(90) - 20 ms) and atrial (APD(90) - 30 ms) action potentials. 4. The magnitude of the sustained current response following premature stimulation was similar to that recorded during the first action potential for ventricular action potential waveforms. However, for Purkinje and atrial action potentials the sustained current response was significantly larger during the premature action potential than during the normally paced action potential. 5. A Markov model that included three closed states, one open and one inactivated state with transitions permitted between the pre-open closed state and the inactivated state, successfully reproduced our results for the effects of premature stimuli, both during square pulse and action potential clamp waveforms. 6. These properties of HERG K(+) channels may help to suppress arrhythmias initiated by early afterdepolarizations and premature beats in the ventricles, Purkinje fibres or atria.
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Affiliation(s)
- Y Lu
- Section of Cardiovascular Biology, Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
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Abstract
Klf9 and Klf13 are members of the C(2)H(2) zinc finger family of transcription factors that are thought to be involved in regulating basal transcription. The mRNA localization of Klf9 and Klf13 during development was determined by in situ hybridization of mouse E8, E11, E13 and E16 embryo sections. The data showed that Klf9 and Klf13 are widely expressed at all the mouse embryo stages examined. Whilst the expression patterns of the two genes largely overlap there are differences in the localization or level of expression in some tissues. At E11, both genes are expressed in high levels in the cephalic mesenchyme whilst Klf13 and not Klf9 is expressed at high levels in the developing heart at E8 and E11. In the gut and bladder at E16, Klf13 is expressed in the epithelial cell layer whereas Klf9 is expressed in both the muscle and epithelial layers. Both Klf9 and Klf13 are expressed at high levels in the epidermis at E11, E13 and E16.
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Affiliation(s)
- K M Martin
- Section of Cardiovascular Biology, Department of Biochemistry, Cambridge University, Tennis Court Road, Cambridge CB2 1QW, UK
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16
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Lücke CD, Philpott A, Metcalfe JC, Thompson AM, Hughes-Davies L, Kemp PR, Hesketh R. Inhibiting mutations in the transforming growth factor beta type 2 receptor in recurrent human breast cancer. Cancer Res 2001; 61:482-5. [PMID: 11212236] [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: 02/19/2023]
Abstract
Members of the transforming growth factor beta (TGF-beta) family are potent inhibitors of the growth of many epithelial cell types. Transmembrane signaling by TGF-beta occurs via a complex of the serine/threonine kinases TGF-beta type 1 receptor and TGF-beta type 2 receptor (TGFBR2), and inactivating mutations in the latter have recently been detected in some primary tumors and in several types of tumor-derived cell lines. The most common mutations that have been identified in TGFBR2 are frameshifts in a repetitive polyadenine region in replication error-positive colorectal carcinomas that result in a truncated protein and absence of receptor expression at the cell surface. A number of point mutations in the highly conserved serine/threonine kinase domain of TGFBR2 have also been reported, some of which have been correlated with either loss of trans-phosphorylation of TGF-beta type 1 receptor or constitutive activation of trans-phosphorylation. No TGFBR2 mutations have been reported in human breast tumors, but anomalous expression of TGF-beta in breast carcinomas suggests that TGF-beta signaling may be defective. We have therefore systematically examined unmatched sets of 17 primary and 17 recurrent breast tumor samples for mutations in TGFBR2, restricted to those regions of the gene in which mutations have previously been reported. None of the previously reported mutations was detected, but four novel mutations (V387M, N435S, V447A, and L452M) were found in the kinase domain in recurrent tumors. No mutations were detected in primary tumors. TGF-beta signaling was significantly inhibited by each of the N435S, V447A, and L452M mutations.
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MESH Headings
- Animals
- Breast Neoplasms/genetics
- Breast Neoplasms/pathology
- DNA Mutational Analysis
- DNA, Neoplasm/chemistry
- DNA, Neoplasm/genetics
- Embryo, Nonmammalian/cytology
- Embryo, Nonmammalian/drug effects
- Embryo, Nonmammalian/metabolism
- Humans
- Mutation
- Neoplasm Recurrence, Local/genetics
- Neoplasm Recurrence, Local/pathology
- Polymorphism, Single-Stranded Conformational
- Protein Serine-Threonine Kinases
- RNA/administration & dosage
- RNA/genetics
- Receptor, Transforming Growth Factor-beta Type II
- Receptors, Transforming Growth Factor beta/genetics
- Transforming Growth Factor beta/pharmacology
- Transforming Growth Factor beta1
- Xenopus
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Affiliation(s)
- C D Lücke
- Department of Biochemistry, University of Cambridge, United Kingdom
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Ellis PD, Chen Q, Barker PJ, Metcalfe JC, Kemp PR. Nov gene encodes adhesion factor for vascular smooth muscle cells and is dynamically regulated in response to vascular injury. Arterioscler Thromb Vasc Biol 2000; 20:1912-9. [PMID: 10938011 DOI: 10.1161/01.atv.20.8.1912] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.1] [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: 11/16/2022]
Abstract
Nephroblastoma overexpressed (NOV) is a member of the CCN family (connective tissue growth factor, CYR61, and NOV) of proteins that are involved in regulating the proliferation, differentiation, and adhesion of a variety of cell types. We have examined the expression of the NOV: gene and NOV protein by vascular smooth muscle cells (VSMCs), in vitro and in vivo, and the effects of recombinant NOV on VSMCs. Rat aortic VSMCs were found to express NOV: mRNA and NOV protein in vitro and in vivo. NOV: expression in adult rat tissues was very high in the aorta and was detected only weakly in the brain and lung by Northern analysis (relative levels 33:3:1). During postnatal development (3 days to 12 weeks), the expression of NOV: was correlated with markers of the differentiated smooth muscle cell phenotype (smooth muscle myosin heavy chain and SM22 alpha). In the rat carotid artery balloon injury model, NOV: was detectable by in situ hybridization and was downregulated in the media of the injured artery compared with the uninjured artery at 7 and 14 days after injury. Expression in the developing intima was barely detectable at 7 days after injury except for strong expression at the luminal surface. At 14 days after injury, NOV: expression was substantially increased throughout the intima. In vitro studies of the function of NOV protein showed that it promoted VSMC adhesion via a mechanism that was divalent cation and Arg-Gly-Asp independent but that it did not modulate VSMC proliferation or phenotype. The strong expression and dynamic regulation of NOV: in the arterial wall, together with its ability to promote VSMC adhesion, suggest that it may be involved in homeostasis and repair.
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Affiliation(s)
- P D Ellis
- Section of Cardiovascular Biology, Department of Biochemistry, University of Cambridge, Cambridge, UK.
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Kemp PR, Metcalfe JC. Four isoforms of serum response factor that increase or inhibit smooth-muscle-specific promoter activity. Biochem J 2000; 345 Pt 3:445-51. [PMID: 10642500 PMCID: PMC1220776] [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: 02/15/2023]
Abstract
Serum response factor (SRF) is a key transcriptional activator of the c-fos gene and of muscle-specific gene expression. We have identified four forms of the SRF coding sequence, SRF-L (the previously identified form), SRF-M, SRF-S and SRF-I, that are produced by alternative splicing. The new forms of SRF lack regions of the C-terminal transactivation domain by splicing out of exon 5 (SRF-M), exons 4 and 5 (SRF-S) and exons 3, 4 and 5 (SRF-I). SRF-M is expressed at similar levels to SRF-L in differentiated vascular smooth-muscle cells and skeletal-muscle cells, whereas SRF-L is the predominant form in many other tissues. SRF-S expression is restricted to vascular smooth muscle and SRF-I expression is restricted to the embryo. Transfection of SRF-L and SRF-M into C(2)C(12) cells showed that both forms are transactivators of the promoter of the smooth-muscle-specific gene SM22alpha, whereas SRF-I acted as a dominant negative form of SRF.
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MESH Headings
- Alternative Splicing
- Animals
- Carcinoma, Embryonal
- Cell Line
- Cloning, Molecular
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Gene Expression Regulation, Developmental
- Mice
- Microfilament Proteins/genetics
- Microfilament Proteins/metabolism
- Muscle Proteins/genetics
- Muscle Proteins/metabolism
- Muscle, Smooth/cytology
- Muscle, Smooth/physiology
- Muscle, Smooth, Vascular/metabolism
- Nuclear Proteins/genetics
- Nuclear Proteins/metabolism
- Promoter Regions, Genetic
- Protein Isoforms/genetics
- Protein Isoforms/metabolism
- RNA, Messenger/metabolism
- Serum Response Factor
- Tumor Cells, Cultured
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Affiliation(s)
- P R Kemp
- Section of Cardiovascular Biology, Department of Biochemistry, University of Cambridge, The Downing Site, Tennis Court Road, Cambridge CB2 1QW, U.K.
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Martin KM, Cooper WN, Metcalfe JC, Kemp PR. Mouse BTEB3, a new member of the basic transcription element binding protein (BTEB) family, activates expression from GC-rich minimal promoter regions. Biochem J 2000; 345 Pt 3:529-33. [PMID: 10642511 PMCID: PMC1220787] [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: 02/15/2023]
Abstract
Members of the three-zinc-finger family of transcription factors play an important role in determining basal transcription. We have cloned mouse BTEB3 (mBTEB3), a new member of the basic transcription element binding protein (BTEB) family, which is expressed in a wide variety of tissues. mBTEB3 activates transcription of the simian virus 40 early promoter (4-fold) and of the tissue-specific SM22alpha promoter (100-fold), suggesting that, like BTEB1 and Sp1, mBTEB3 is a basal transcription factor.
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Affiliation(s)
- K M Martin
- Section of Cardiovascular Biology, Department of Biochemistry, Cambridge University, Tennis Court Road, Cambridge CB2 1QW, U.K
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20
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Grainger DJ, Heathcote K, Chiano M, Snieder H, Kemp PR, Metcalfe JC, Carter ND, Spector TD. Genetic control of the circulating concentration of transforming growth factor type beta1. Hum Mol Genet 1999; 8:93-7. [PMID: 9887336 DOI: 10.1093/hmg/8.1.93] [Citation(s) in RCA: 559] [Impact Index Per Article: 22.4] [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: 12/13/2022] Open
Abstract
The concentration of transforming growth factor beta (TGF-beta) in plasma has been correlated with the development of several diseases, including atherosclerosis and certain forms of cancer. However, the mechanisms that control the concentration of TGF-beta in plasma are poorly understood. In a study of 170 pairs of female twins (average age 57.7 years) we show that the concentration of active plus acid-activatable latent TGF-beta1 [(a+l) TGF-beta therefore is predominantly under genetic control (heritability estimate 0.54). Single strand conformation polymorphism (SSCP) mapping of the TGF-beta1 gene promoter has identified two single base substitution polymorphisms. The two polymorphisms (G-->A at position -800 bp and C-->T at position -509 bp) are in linkage disequilibrium (correlation coefficient Delta = 0.215, P < 0.01). The C-509T polymorphism is significantly associated with the plasma concentration of (a+l) TGF-beta1, explaining 8.2% of the additive genetic variance of (a+l) TGF-beta1 concentration. It is therefore possible that predisposition to atherosclerosis, bone diseases or various forms of cancer may be correlated with the presence of particular alleles at the TGFB1 locus.
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Affiliation(s)
- D J Grainger
- Department of Medicine, University of Cambridge, Box 157, Addenbrooke's Hospital, Hills Road, Cambridge CB2 2QQ, UK
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Syrris P, Carter ND, Metcalfe JC, Kemp PR, Grainger DJ, Kaski JC, Crossman DC, Francis SE, Gunn J, Jeffery S, Heathcote K. Transforming growth factor-beta1 gene polymorphisms and coronary artery disease. Clin Sci (Lond) 1998; 95:659-67. [PMID: 9831690 DOI: 10.1042/cs0950659] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.1] [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: 11/17/2022]
Abstract
1. Transforming growth factor-beta1 is a cytokine with a very wide spectrum of biological activities. Previous studies have shown that it is involved in a number of physiological and pathological processes including heart disease. In our study we aimed to scan the transforming growth factor-beta1 locus for polymorphisms and to identify haplotypes significantly associated with a predisposition to coronary atherosclerosis.2. Two patient groups comprising 244 angiographically normal individuals and 655 patients with coronary artery disease were recruited from London and Sheffield. DNA samples from these subjects were screened for mutations in the transforming growth factor-beta1 locus and all subjects were genotyped by a coupled polymerase chain reaction-restriction enzyme digestion method.3. Five polymorphisms have been identified in the transforming growth factor-beta1 gene at positions G-800A, C-509T in the promoter region, Leu10-->Pro, Arg25-->Pro in exon 1 and Thr263-->Ile in exon 5. No significant difference in frequencies for any of the five polymorphisms was found between controls and patients with coronary artery disease. Similarly, there was no correlation between these polymorphisms and hypertension.4. The genotypes of all the individuals participating in the study were assigned to seven main haplotypes of the transforming growth factor-beta1 locus. Based on species comparison data we propose that GCCGC is the ancestral haplotype in humans.5. Our data suggest that these transforming growth factor-beta1 polymorphisms are not associated with coronary artery disease and therefore their presence alone would not be a genetic risk factor for predisposition to coronary artery disease.
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Affiliation(s)
- P Syrris
- Medical Genetics Unit, St George's Hospital Medical School, Cranmer Terrace, London SW170RE, U.K
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22
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Abstract
Latent transforming growth factor beta binding protein-1 (LTBP1) is important in regulating the localisation and activation of transforming growth factor beta(TGFbeta). Three forms of LTBP1 mRNA have previously been described, LTBP1L, LTBP1S and LTBPdelta53. Here, we have analysed the LTBP1 coding sequence and identified two other spliced forms, LTBP1delta55 and LTBP1delta41. LTBP1delta55 is a short form of LTBPIL which lacks 55 amino acids including two consensus N-glycosylation sites and LTBP1delta41 is a form of LTBP1 which lacks the 12th EGF-like repeat. Furthermore, sequencing of genomic clones showed that splicing to generate LTBP1L occurs using an intra-exonic 3' splice acceptor site in the first coding exon of LTBP1S and that LTBP1delta55 arises from the alternative use of an exonic 3' splice acceptor site at the end of the following intron. LTBP1delta41 arises from skipping the exon which encodes the 12th EGF-like repeat. LTBP1delta55 and LTBP1delta41 mRNA are expressed in a wide variety of human tissues but the proportions of each splice form vary in the tissues.
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Affiliation(s)
- R Oklü
- Department of Biochemistry, University of Cambridge, UK.
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23
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Oklü R, Metcalfe JC, Hesketh TR, Kemp PR. Loss of a consensus heparin binding site by alternative splicing of latent transforming growth factor-beta binding protein-1. FEBS Lett 1998; 425:281-5. [PMID: 9559666 DOI: 10.1016/s0014-5793(98)00257-9] [Citation(s) in RCA: 24] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Latent transforming growth factor-beta binding protein-1 (LTBP-1), plays an important role in controlling localisation and activation of transforming growth factor-beta (TGF-beta). We show that alternative splicing generates a form of mRNA which lacks bases 1277-1435 (termed LTBP-1delta53). The 53 amino acids encoded by these bases include the eighth cysteine of the first cysteine repeat and a consensus heparin binding sequence. Sequencing of genomic clones showed that alternative splicing resulted from the use of an intra-exonic 3' splice acceptor site. The loss of the heparin binding site implies that LTBP-1delta53 will bind to the extracellular matrix less efficiently than LTBP-1.
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Affiliation(s)
- R Oklü
- Department of Biochemistry, Cambridge University, UK.
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24
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Abstract
We have cloned and sequenced a 1.9 kb fragment of the 5'-upstream sequence of the smooth-muscle-specific gene SM22 alpha. The region cloned consisted of the SM22 alpha promoter, a 65 bp exon containing most of the 5'-untranslated region and 307 bp of the first intron. A 1.5 kb fragment at the 5' end of this sequence was able to drive the expression of a reporter chloramphenicol acetyltransferase (CAT) gene in both vascular smooth-muscle cells and Rat-1 fibroblasts. This promoter region did not contain a consensus TATAA box but contained the sequence TTTAAA 25 bp from the major start site identified by primer extension. Deletion analysis showed that a fragment of the promoter from +65 to -303 was more active in both cell types than the 1.5 kb fragment suggesting that there are silencer sequences in the region 5' to the core promoter. CAT activity was also observed with fragments containing bases +65 to -193 and +65 to -117 in smooth-muscle cells. In contrast with the smooth-muscle cells, no CAT activity was detected in Rat-1 fibroblasts with the smallest two fragments. The residual promoter activity in the smallest fragment of the SM22 alpha promoter tested suggested that, unlike the smooth-muscle alpha-actin promoter, transcription from the SM22 alpha promoter can occur in smooth-muscle cells in the absence of factors binding to CC(A/Trich)6GG (CArG box) or CANNTG (E box) motifs.
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Affiliation(s)
- P R Kemp
- Department of Biochemistry, Cambridge University, U.K
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25
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Kemp PR, Metcalfe JC, Grainger DJ. ID--a dominant negative regulator of skeletal muscle differentiation--is not involved in maturation or differentiation of vascular smooth muscle cells. FEBS Lett 1995; 368:81-6. [PMID: 7615094 DOI: 10.1016/0014-5793(95)00605-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [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: 01/26/2023]
Abstract
Rat aortic vascular smooth muscle cells (VSMCs) expressing the MyoD gene formed myotubes at a low frequency in the presence of serum but at a high frequency in the absence of serum. Expression of an antisense Id gene increased myotube formation in the presence of serum indicating that a reduction in Id levels is a major mechanism by which serum withdrawal promotes myotube formation. The role of Id in the development of VSMCs was investigated by expressing an antisense Id gene in neonatal VSMCs. No evidence was found for the conversion of neonatal VSMCs to adult VSMCs in the presence of the antisense Id gene. Similarly reduction in Id by serum withdrawal also failed to cause conversion of the neonatal VSMCs to the adult phenotype. These data suggest that the maturation of neonatal smooth muscle cells is not controlled by a VSMC homologue of the skeletal muscle basic-helix-loop-helix proteins.
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Affiliation(s)
- P R Kemp
- Department of Biochemistry, Cambridge University, UK
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26
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Abstract
Assays which measure active and latent forms of transforming growth factor beta (TGF-beta) separately in human serum and plasma are required to investigate the biological role of TGF-beta in a variety of human diseases. We have developed an enzyme-linked immunosorbent assay (ELISA) using two polyclonal antibodies against TGF-beta which rapidly determines the amount of active plus acid-activatable, latent TGF-beta forms ((a+l)TGF-beta) present in human serum and plasma in the range 4 pmol/l to 2000 pmol/l. To measure active TGF-beta alone, we have developed a second ELISA using the extracellular domain of the TGF-beta type II receptor as the capture reagent which detects active TGF-beta in serum and plasma samples in the range 20 pmol/l to 4000 pmol/l. Both assays detect TGF-beta 1 and TGF-beta 3 with similar sensitivity, are > 10-fold less sensitive to TGF-beta 2 and are not affected by a range of other peptide growth factors. The mean (a+l)TGF-beta present in human serum was 330 pmol/l but the range was very large (< 4 pmol/l to 1400 pmol/l). The mean active TGF-beta present was 230 pmol/l (range < 20 pmol/l to 1400 pmol/l) and the proportion of the (a+l)TGF-beta present which was active [a/(a+l)] varied from < 10% to 100%. The concentration of (a+l)TGF-beta and the proportion of TGF-beta which was active were very similar in the serum and platelet-poor plasma prepared from the same whole blood sample. The clot formed during serum preparation retained all of the TGF-beta which was detected by the (a+l)TGF-beta ELISA in the corresponding platelet releasate, although the PDGF in platelets was released into the serum. In contrast, platelet-poor plasma contained no detectable PDGF demonstrating that the (a+l)TGF-beta assayed in the plasma was not due to platelet degranulation after bleeding. Serum active TGF-beta and (a+l)TGF-beta concentrations therefore provide a reliable estimate of these forms of TGF-beta present in plasma.
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Affiliation(s)
- D J Grainger
- Department of Biochemistry, University of Cambridge, UK
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27
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Grainger DJ, Kemp PR, Metcalfe JC, Liu AC, Lawn RM, Williams NR, Grace AA, Schofield PM, Chauhan A. The serum concentration of active transforming growth factor-beta is severely depressed in advanced atherosclerosis. Nat Med 1995; 1:74-9. [PMID: 7584958 DOI: 10.1038/nm0195-74] [Citation(s) in RCA: 288] [Impact Index Per Article: 9.9] [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: 01/26/2023]
Abstract
Recent evidence has led us to propose that transforming growth factor-beta (TGF-beta) is a key inhibitor of atherosclerosis. We show here that a population of patients with advanced atherosclerosis all have less active TGF-beta in their sera than patients with normal coronary arteries, with a fivefold difference in average concentration between the two groups. This correlation with atherosclerosis is much stronger than for other known major risk factors and it may therefore have important diagnostic and prognostic significance. Aspirin medication correlates with an increase in active TGF-beta concentration, indicating that therapeutic interventions for TGF-beta are possible.
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Affiliation(s)
- D J Grainger
- Department of Biochemistry, University of Cambridge, UK
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28
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Abstract
A HIGH concentration of serum lipoprotein(a) is a risk factor for atherosclerosis. Lipoprotein(a) consists of low-density lipoprotein with the additional protein component, apolipoprotein(a), a homologue of plasminogen. Lipoprotein(a) and apolipoprotein(a) enhance proliferation of human vascular smooth muscle cells (hVSMCs) in culture by inhibiting activation of plasminogen to plasmin, thus blocking the proteolytic activation of transforming growth factor-beta (TGF-beta), an autocrine inhibitor of hVSMC proliferation. The hypothesis that this pathway is a key step in atherogenesis is tested on transgenic mice expressing the human apolipoprotein(a) gene. We show here that the activation of TGF-beta is inhibited in the aortic wall and serum of mice expressing apolipoprotein(a), as a consequence of apolipoprotein(a) inhibition of plasminogen activation. These effects are closely correlated with VSMC activation.
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Affiliation(s)
- D J Grainger
- Department of Biochemistry, University of Cambridge, UK
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29
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Grainger DJ, Kemp PR, Witchell CM, Weissberg PL, Metcalfe JC. Transforming growth factor beta decreases the rate of proliferation of rat vascular smooth muscle cells by extending the G2 phase of the cell cycle and delays the rise in cyclic AMP before entry into M phase. Biochem J 1994; 299 ( Pt 1):227-35. [PMID: 8166645 PMCID: PMC1138046 DOI: 10.1042/bj2990227] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.8] [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: 01/29/2023]
Abstract
Transforming growth factor beta 1 (TGF-beta 1) decreased the rate of proliferation of rat aortic vascular smooth muscle cells (VSMCs) stimulated with serum showing a maximal effect at > 5 ng/ml (200 pM). However, it did not reduce the proportion of cells which passed through S phase (> 90%) and entry into S phase was delayed by less than 3 h. The proportion of cells passing through M phase (> 90%) was also unaffected, but entry into mitosis was delayed by approx. 24 h. This increase in cell cycle time was therefore due mainly to an increase in the G2 to mitotic metaphase period. Addition of TGF-beta 1 late in G1 or late in S phase failed to delay the onset of mitosis, but the presence of TGF-beta 1 between 0 and 12 h after the addition of serum to quiescent cells was sufficient to cause the maximal delay in mitosis of approx. 24 h. The role of cyclic AMP in the mechanism of the TGF-beta 1 effects on the cell cycle was examined. Entry into mitosis was preceded by a transient 2-fold increase in cyclic AMP concentration and TGF-beta 1 delayed both this increase in cyclic AMP and entry into mitosis to the same extent. Addition of forskolin or 8-(4-chlorophenylthio)-cyclic AMP to cells 30 h after stimulation with serum completely reversed the increase in duration of G2 in the presence of TGF-beta 1, suggesting that the rise in cyclic AMP levels which precedes mitosis might trigger entry of the VSMCs into M phase. Addition of forskolin late in S phase (26 h after stimulation with serum) advanced the entry of the cells into M phase and they divided prematurely. This effect was unaffected by the addition of cycloheximide with the forskolin; however, the effect of forskolin on cell division was completely inhibited when cycloheximide was added late in G1. TGF-beta 1 prevented the loss of smooth-muscle-specific myosin heavy chain (SM-MHC), which occurs in primary VSMC cultures in the presence or absence of serum, and the cells proliferated while maintaining a differentiated phenotype. However, TGF-beta 1 did not cause re-differentiation of subcultured VSMCs which contained very low amounts of SM-MHC and the effect of TGF-beta 1 in extending the G2 phase of the cell cycle is exerted independently of its effect on differentiation.
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Affiliation(s)
- D J Grainger
- Department of Biochemistry, University of Cambridge, U.K
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30
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Kemp PR, Shachar-Hill Y, Weissberg PL, Metcalfe JC. Inhibition of PDGF BB stimulated DNA synthesis in rat aortic vascular smooth muscle cells by the expression of a truncated PDGF beta receptor. FEBS Lett 1993; 336:119-23. [PMID: 8262192 DOI: 10.1016/0014-5793(93)81623-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [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: 01/29/2023]
Abstract
Rat aortic vascular smooth muscle cells (VSMCs) were transfected with a vector encoding a truncated human PDGF beta receptor or the full-length human PDGF beta receptor. Cells stably expressing the truncated human PDGF beta receptor or the full-length human PDGF beta receptor were selected and the effect of PDGF BB on DNA synthesis in these cells was studied. Cells expressing the full-length PDGF beta receptor entered DNA synthesis normally, however, cells expressing the truncated PDGF beta receptor failed to enter DNA synthesis in response to PDGF BB. These data show that the mitogenic response of rat aortic vascular smooth muscle cells to PDGF BB can be inhibited by the expression of a truncated PDGF beta receptor.
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Affiliation(s)
- P R Kemp
- Department of Biochemistry, Cambridge University, UK
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31
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Kemp PR, Grainger DJ, Shanahan CM, Weissberg PL, Metcalfe JC. The Id gene is activated by serum but is not required for de-differentiation in rat vascular smooth muscle cells. Biochem J 1991; 277 ( Pt 1):285-8. [PMID: 1854341 PMCID: PMC1151222 DOI: 10.1042/bj2770285] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [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: 12/29/2022]
Abstract
Primary rat vascular smooth muscle cells cultured on fibronectin in the absence of serum lost smooth-muscle-specific myosin heavy chain but did not enter the cell cycle and proliferate until they were stimulated by serum. Under these conditions accumulation of Id mRNA occurred only in response to serum and was maximal during the G1 phase of the cycle.
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Affiliation(s)
- P R Kemp
- Department of Biochemistry, University of Cambridge, U.K
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32
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Affiliation(s)
- P R Kemp
- Department of Biochemistry, Oxford University, U.K
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33
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Kemp PR, Bailey IA, Radda GK, Seymour AM. Evidence for the compartmentation of the enzymes of cyclic AMP metabolism. Biochem Soc Trans 1990; 18:473-4. [PMID: 2164994 DOI: 10.1042/bst0180473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- P R Kemp
- Department of Biochemistry, Oxford University, U.K
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34
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Abstract
The metabolic and physiological responses of hearts from male rats and guinea-pigs to isoprenaline and SK&F 94120 (a phosphodiesterase III inhibitor), have been studied. Doses which gave similar chronotropic stimulation gave different inotropic responses. In both species, isoprenaline generated a greater increase in developed tension than SK&F 94120. With both drugs the inotropic response in the rat was less than than in the guinea-pig. 31P-NMR investigation of high-energy phosphate levels showed reduction in PCr concentration and an accompanying acidosis in the isoprenaline-perfused rat heart only. In both species, lactate production was stimulated by SK&F 94120 but not by isoprenaline. These results are discussed with reference to G-protein activation of ion channels and differences in Ca2+ handling by the two species.
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Affiliation(s)
- P R Kemp
- Department of Biochemistry, University of Oxford, U.K
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35
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Kemp PR. Points from letters: Personal view. West J Med 1969. [DOI: 10.1136/bmj.4.5683.624-d] [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: 11/04/2022]
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36
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37
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38
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39
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Kemp PR. Psychiatry in the Services. West J Med 1945. [DOI: 10.1136/bmj.2.4428.706-b] [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: 11/04/2022]
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40
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Kemp PR. Development of Health Services. West J Med 1935. [DOI: 10.1136/bmj.2.3887.40-b] [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: 11/04/2022]
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41
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Kemp PR. Rest in the Treatment of Neuroses. West J Med 1934. [DOI: 10.1136/bmj.1.3810.79-a] [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: 11/03/2022]
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42
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Kemp PR. The School Medical Service. West J Med 1932. [DOI: 10.1136/bmj.2.3752.1036-a] [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: 11/04/2022]
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43
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