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Groot J, MacLellan A, Butler M, Todor E, Zulfiqar M, Thackrah T, Clarke C, Brosnan M, Ainsworth B. The Effectiveness of Fully Automated Digital Interventions in Promoting Mental Well-Being in the General Population: Systematic Review and Meta-Analysis. JMIR Ment Health 2023; 10:e44658. [PMID: 37856172 PMCID: PMC10623223 DOI: 10.2196/44658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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: 11/28/2022] [Revised: 06/30/2023] [Accepted: 07/07/2023] [Indexed: 10/20/2023] Open
Abstract
BACKGROUND Recent years have highlighted an increasing need to promote mental well-being in the general population. This has led to a rapidly growing market for fully automated digital mental well-being tools. Although many individuals have started using these tools in their daily lives, evidence on the overall effectiveness of digital mental well-being tools is currently lacking. OBJECTIVE This study aims to review the evidence on the effectiveness of fully automated digital interventions in promoting mental well-being in the general population. METHODS Following the preregistration of the systematic review protocol on PROSPERO, searches were carried out in MEDLINE, Web of Science, Cochrane, PsycINFO, PsycEXTRA, Scopus, and ACM Digital (initial searches in February 2022; updated in October 2022). Studies were included if they contained a general population sample and a fully automated digital intervention that exclusively used psychological mental well-being promotion activities. Two reviewers, blinded to each other's decisions, conducted data selection, extraction, and quality assessment of the included studies. Narrative synthesis and a random-effects model of per-protocol data were adopted. RESULTS We included 19 studies that involved 7243 participants. These studies included 24 fully automated digital mental well-being interventions, of which 15 (63%) were included in the meta-analysis. Compared with no intervention, there was a significant small effect of fully automated digital mental well-being interventions on mental well-being in the general population (standardized mean difference 0.19, 95% CI 0.04-0.33; P=.02). Specifically, mindfulness-, acceptance-, commitment-, and compassion-based interventions significantly promoted mental well-being in the general population (P=.006); insufficient evidence was available for positive psychology and cognitive behavioral therapy-based interventions; and contraindications were found for integrative approaches. Overall, there was substantial heterogeneity, which could be partially explained by the intervention duration, comparator, and study outcomes. The risk of bias was high, and confidence in the quality of the evidence was very low (Grading of Recommendations, Assessment, Development, and Evaluations), primarily because of the high rates of study dropout (average 37%; range 0%-85%) and suboptimal intervention adherence (average 40%). CONCLUSIONS This study provides a novel contribution to knowledge regarding the effectiveness, strengths, and weaknesses of fully automated digital mental well-being interventions in the general population. Future research and practice should consider these findings when developing fully automated digital mental well-being tools. In addition, research should aim to investigate positive psychology and cognitive behavioral therapy-based tools as well as develop further strategies to improve adherence and reduce dropout in fully automated digital mental well-being interventions. Finally, it should aim to understand when and for whom these interventions are particularly beneficial. TRIAL REGISTRATION PROSPERO CRD42022310702; https://tinyurl.com/yc7tcwy7.
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Affiliation(s)
- Julia Groot
- Department of Psychology, University of Bath, Bath, United Kingdom
| | | | - Madelaine Butler
- Department of Psychology, University of Bath, Bath, United Kingdom
| | - Elisa Todor
- Department of Psychology, University of Bath, Bath, United Kingdom
| | - Mahnoor Zulfiqar
- Department of Psychology, University of Bath, Bath, United Kingdom
| | | | - Christopher Clarke
- Department of Computer Science, University of Bath, Bath, United Kingdom
| | - Mark Brosnan
- Centre for Applied Autism Research, Department of Psychology, University of Bath, Bath, United Kingdom
| | - Ben Ainsworth
- School of Psychology, Faculty of Environmental and Life Sciences, University of Southampton, Southampton, United Kingdom
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Brown MEL, MacLellan A, Laughey W, Omer U, Himmi G, LeBon T, Finn GM. Can stoic training develop medical student empathy and resilience? A mixed-methods study. BMC Med Educ 2022; 22:340. [PMID: 35505329 PMCID: PMC9064267 DOI: 10.1186/s12909-022-03391-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [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: 06/04/2021] [Accepted: 04/21/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Empathic erosion and burnout represent crises within medicine. Psychological training has been used to promote empathy and personal resilience, yet some training useful within adjacent fields remain unexplored, e.g., Stoic training. Given recent research within psychology suggesting that Stoic training increases emotional wellbeing, exploring this type of training within health professions education is important. We therefore asked: What impact would a Stoicism informed online training package have on third year medical students' resilience and empathy? METHODS 24 third year medical students took part in 12 days of online training (SeRenE), based on Stoic philosophy, and co-developed with psychotherapists. A mixed-methods study was conducted to evaluate impact. Pre- and post-SeRenE students completed the Stoic Attitudes and Behaviours Scale (SABS), Brief Resilience Scale (BRS) and Jefferson Scale of Empathy (JSE). All students completed semi-structured interviews following training and 2 months post-SeRenE. Thematic analysis was employed to analyse qualitative data, whilst within subjects t-tests and correlational analyses were conducted on quantitative data. RESULTS Quantitatively, stoic ideation, resilience and empathy increased post-training, with correlational analyses suggesting resilience and empathy increase in tandem. Qualitatively, four themes were identified: 1. Negative visualisation aids emotional and practical preparedness; 2. Stoic mindfulness encourages students to think about how they think and feel; 3. Stoic reflection develops the empathic imagination; and 4. Evaluating the accessibility of SeRenE. CONCLUSIONS Our data lend support to the ability of Stoic-based psychological training to positively influence resilience and empathy. Although, quantitatively, results were mixed, qualitative data offers rich insight. The practice of negative visualisation, promoted by SeRenE, encourages student self-efficacy and planning, domains of resilience associated with academic success. Further, this study demonstrates a connection between Stoic practice and empathy, which manifests through development of the empathic imagination and a sense of empathic bravery.
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Affiliation(s)
- Megan E L Brown
- Health Professions Education Unit, Hull York Medical School, University of York, York, UK.
| | | | - William Laughey
- Health Professions Education Unit, Hull York Medical School, University of York, York, UK
| | - Usmaan Omer
- Health Professions Education Unit, Hull York Medical School, University of York, York, UK
| | - Ghita Himmi
- Health Professions Education Unit, Hull York Medical School, University of York, York, UK
| | | | - Gabrielle M Finn
- Health Professions Education Unit, Hull York Medical School, University of York, York, UK
- School of Medical Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
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Stubbs H, MacLellan A, McGettrick M, Jani B, Brewis M, Church C, Johnson M. Predicting Group II pulmonary hypertension: diagnostic accuracy of the H2FPEF and OPTICS scores in Scotland. Open Heart 2022; 9:openhrt-2022-002023. [PMID: 35477699 PMCID: PMC9047890 DOI: 10.1136/openhrt-2022-002023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Accepted: 04/07/2022] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE Group II pulmonary hypertension (PH) can be challenging to distinguish from Group I PH without proceeding to right heart catheterisation (RHC). The diagnostic accuracy of the H2FPEF and OPTICS scores was investigated in Scotland. METHODS Patients were included in the study if they were referred to the Scottish Pulmonary Vascular Unit between 2016 and 2020 and subsequently diagnosed with Group II PH or Group I PH which was either idiopathic, heritable or pulmonary veno-occlusive disease. The established cut offs for the H2FPEF and for the OPTICS scores were applied retrospectively to predict the presence of Group II PH. The diagnosis from the scores were compared with the MDT consensus diagnosis following RHC. RESULTS 107 patients with Group I PH and 86 patients with Group II PH were included. Retrospective application of the OPTICS score demonstrated that pretest scoring would detect 28% of cases with Group II PH yet at the cost of misdiagnosing 4% of patients with Group I as Group II PH (specificity 0.96). The H2FPEF score had a far greater sensitivity (0.70) yet reduced specificity (0.91), leading to misdiagnosis of 9% of Group I PH cases. CONCLUSION While the specificity of these scores was high, the lack of perfect specificity limits their utility as it results in missed patients with Group I PH. As a consequence, they cannot replace RHC as the means of diagnosing the aetiology of PH in their current form. The scores may still be used to support clinical judgement or to indicate the advisability for further provocative testing at RHC.
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Affiliation(s)
- Harrison Stubbs
- Scottish Pulmonary Vascular Unit, NHS Greater Glasgow and Clyde, Glasgow, UK .,Institute of Health & Wellbeing, University of Glasgow, Glasgow, UK
| | - Alexander MacLellan
- Scottish Pulmonary Vascular Unit, NHS Greater Glasgow and Clyde, Glasgow, UK.,Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow, UK
| | - Michael McGettrick
- Scottish Pulmonary Vascular Unit, NHS Greater Glasgow and Clyde, Glasgow, UK.,Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow, UK
| | - Bhautesh Jani
- Institute of Health & Wellbeing, University of Glasgow, Glasgow, UK
| | - Melanie Brewis
- Scottish Pulmonary Vascular Unit, NHS Greater Glasgow and Clyde, Glasgow, UK.,Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow, UK
| | - Colin Church
- Scottish Pulmonary Vascular Unit, NHS Greater Glasgow and Clyde, Glasgow, UK.,Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow, UK
| | - Martin Johnson
- Scottish Pulmonary Vascular Unit, NHS Greater Glasgow and Clyde, Glasgow, UK.,Institute of Cardiovascular & Medical Sciences, University of Glasgow, Glasgow, UK
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Stubbs H, MacLellan A, Lua S, Dormand H, Church C. The right ventricle under pressure: Anatomy and imaging in sickness and health. J Anat 2022; 242:17-28. [PMID: 35285014 PMCID: PMC9773164 DOI: 10.1111/joa.13654] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [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] [Received: 11/12/2021] [Revised: 01/28/2022] [Accepted: 03/02/2022] [Indexed: 12/25/2022] Open
Abstract
The right ventricle (RV) is an important structure which serves a multitude of vital physiological functions in health. For many years, the left ventricle has dominated the focus of understanding in both biology and pathophysiology and the RV was felt to be more of a passive structure which rarely had an effect on disease states. However, it is increasingly recognised that the RV is essential to the homoeostasis of normal physiology and disturbances in RV structure and function have a substantial effect on patient outcomes. Indeed, the prognosis of diseases of lung diseases affecting the pulmonary vasculature and left heart disease is intimately linked to the function of the right ventricle. This review sets out to describe the developmental and anatomical complexities of the right ventricle while exploring the modern techniques employed to image and understand its function from a clinical perspective.
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Affiliation(s)
- Harrison Stubbs
- Scottish Pulmonary Vascular Unit, Golden Jubilee National HospitalGlasgowScotland,University of GlasgowGlasgowScotland
| | - Alexander MacLellan
- Scottish Pulmonary Vascular Unit, Golden Jubilee National HospitalGlasgowScotland,University of GlasgowGlasgowScotland
| | - Stephanie Lua
- Scottish Pulmonary Vascular Unit, Golden Jubilee National HospitalGlasgowScotland
| | - Helen Dormand
- Scottish Pulmonary Vascular Unit, Golden Jubilee National HospitalGlasgowScotland
| | - Colin Church
- Scottish Pulmonary Vascular Unit, Golden Jubilee National HospitalGlasgowScotland,University of GlasgowGlasgowScotland
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McGettrick M, MacLellan A, McCaughey P, Bagot C, Brewis MJ, Lang NN, Johnson MK, Church AC. Pulmonary thromboembolism in hospitalised patients with COVID-19: a retrospective national study of patients managed in critical care and ward environments in Scotland. BMJ Open 2021; 11:e050281. [PMID: 34462282 PMCID: PMC8406462 DOI: 10.1136/bmjopen-2021-050281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
OBJECTIVES To assess for increase in pulmonary thromboembolism (PTE) in hospitalised patients with COVID-19, in both critical care and ward environments. SETTING We reviewed all CT pulmonary angiograms (CTPA) performed in Scotland between 23 March 2020 and 31 May 2020 and identified those with COVID-19 using either classical radiological appearances or positive COVID-19 PCR swab. PARTICIPANTS All hospitalised patients in Scotland with COVID-19 between 23 March 2020 and 31 May 2020 who underwent a CTPA. PRIMARY OUTCOME MEASURE To assess if the rate of PTE was increased in those with COVID-19 compared with previously published figures of hospitalised patients. SECONDARY OUTCOME MEASURES To assess the effect of right heart strain or requirement for critical care on mortality. RESULTS 3401 CTPAs were reviewed. 192 were positive for PTE in patients with evidence of COVID-19 either real-time PCR swab positive for SARS-CoV-2 (n=104) or having radiological changes consistent with COVID-19 (n=88). The total number of hospital admissions in Scotland between 23rd March 2020 and 31st May 2020 with COVID-19 was 5195. The incidence of PTE during this time was 3.7% in all patients admitted to all hospitals in Scotland with COVID-19 during this period. 475 hospitalised patients were managed in critical care (both level 2 and level 3 care), in whom the incidence of PTE was 6% (n=29). 4720 patients did not require admission to critical care, in whom the incidence of PTE was 3.5% (n=163). There was increased risk of death with right heart strain (25/52 vs 128/140 (p<0.01)) and in critical care (15/29 vs 146/163 (p<0.01)). CONCLUSIONS We have demonstrated an increased risk of PTE in critical care and ward-based environments. Further studies are required to establish effective prophylactic anticoagulation in this group.
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Affiliation(s)
- Michael McGettrick
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Clydebank, UK
| | - Alexander MacLellan
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Clydebank, UK
| | - Paul McCaughey
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Clydebank, UK
| | - Catherine Bagot
- Department of Haematology, Glasgow Royal Infirmary, Glasgow, UK
| | - Melanie J Brewis
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Clydebank, UK
| | | | - M K Johnson
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Clydebank, UK
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Resasco A, MacLellan A, Ayala MA, Kitchenham L, Edwards AM, Lam S, Dejardin S, Mason G. Cancer blues? A promising judgment bias task indicates pessimism in nude mice with tumors. Physiol Behav 2021; 238:113465. [PMID: 34029586 DOI: 10.1016/j.physbeh.2021.113465] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 04/23/2021] [Accepted: 04/27/2021] [Indexed: 02/06/2023]
Abstract
In humans, affective states can bias responses to ambiguous information: a phenomenon termed judgment bias (JB). Judgment biases have great potential for assessing affective states in animals, in both animal welfare and biomedical research. New animal JB tasks require construct validation, but for laboratory mice (Mus musculus), the most common research vertebrate, a valid JB task has proved elusive. Here (Experiment 1), we demonstrate construct validity for a novel mouse JB test: an olfactory Go/Go task in which subjects dig for high- or low-value food rewards. In C57BL/6 and Balb/c mice faced with ambiguous cues, latencies to dig were sensitive to high/low welfare housing: environmentally-enriched animals responded with relative 'optimism' through shorter latencies. Illustrating the versatility of this validated JB task across different fields of research, it further allowed us to test hypotheses about the mood-altering effects of cancer in male and female nude mice (Experiment 2). Males, although not females, treated ambiguous cues as intermediate; and males bearing subcutaneous lung adenocarcinomas also responded more pessimistically to these than did healthy controls. To our knowledge, this is the first evidence of a valid mouse JB task, and the first demonstration of pessimism in tumor-bearing animals. This task still needs to be refined to improve its sensitivity. However, it has great potential for investigating mouse welfare, the links between affective state and disease, depression-like states in animals, and hypotheses regarding the neurobiological mechanisms that underlie affect-mediated biases in judgment.
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Affiliation(s)
- A Resasco
- Institute of Cell Biology and Neurosciences, National Scientific and Technical Research Council-University of Buenos Aires, Autonomous City of Buenos Aires, Argentina; Laboratory of Experimental Animals, Faculty of Veterinary Sciences, National University of La Plata, La Plata, Argentina
| | - A MacLellan
- Department of Integrative Biology, University of Guelph, Guelph, Canada
| | - M A Ayala
- Laboratory of Experimental Animals, Faculty of Veterinary Sciences, National University of La Plata, La Plata, Argentina
| | - L Kitchenham
- Department of Integrative Biology, University of Guelph, Guelph, Canada
| | - A M Edwards
- Ontario Agricultural College, University of Guelph, Guelph, Canada
| | - S Lam
- Ontario Veterinary College, University of Guelph, Guelph, Canada
| | - S Dejardin
- Formerly Department of Animal Biosciences, University of Guelph, Guelph, Canada
| | - G Mason
- Department of Integrative Biology, University of Guelph, Guelph, Canada.
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MacLellan A, Derakshan N. The Effects of Stoic Training and Adaptive Working Memory Training on Emotional Vulnerability in High Worriers. Cogn Ther Res 2021. [DOI: 10.1007/s10608-020-10183-4] [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: 10/22/2022]
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McGettrick M, McCaughey P, MacLellan A, Brewis M, Church AC, Johnson MK. Social deprivation in Scottish populations with pulmonary hypertension secondary to connective tissue disease and chronic thromboembolic disease. ERJ Open Res 2020; 6:00297-2019. [PMID: 33263038 PMCID: PMC7682671 DOI: 10.1183/23120541.00297-2019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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] [Received: 10/29/2019] [Accepted: 08/12/2020] [Indexed: 11/20/2022] Open
Abstract
Socioeconomic factors have been shown to have an adverse impact on survival in some respiratory diseases. Studies from the USA and China have suggested worse survival in idiopathic pulmonary arterial hypertension in low socioeconomic groups. We looked at the effect of deprivation on the outcomes in patients with connective tissue disease-associated pulmonary hypertension (CTDPH) and chronic thromboembolic pulmonary hypertension (CTEPH) in a retrospective observational study. Data were obtained from 232 patients with CTDPH and 263 with CTEPH who were under the care of the Scottish Pulmonary Vascular Unit, Glasgow, UK. We used Cox proportional hazards regression to assess for a relationship between deprivation and survival. We found no difference in survival across deprivation quintiles in the CTDPH (p=0.26) or CTEPH cohorts (p=0.18). We constructed multivariate models using enrolment time, age, sex and body mass index, with no significant change in findings. There was no difference between expected and observed population distribution of CTDPH (p=0.98) and CTEPH (p=0.36). Whilst there was no difference in presenting functional class in the CTDPH group, the CTEPH patients in more deprived quintiles presented in a worse functional class (p=0.032). There was no difference between quintiles of CTEPH patients who had distal or proximal disease (p=0.75), or who underwent surgery (p=0.5). Increased social deprivation is not associated with worse survival in patients with CTDPH and CTEPH managed in the Scottish National Health Service. Whilst there is no evidence of referral barriers in CTDPH, this may not be the case in CTEPH, as lower deprivation was associated with worse functional class at presentation. Increased social deprivation is not associated with worse survival in patients with connective tissue disease-associated pulmonary hypertension or chronic thromboembolic pulmonary hypertension managed in the Scottish NHShttps://bit.ly/32KbzSv
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Affiliation(s)
- Michael McGettrick
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Glasgow, UK
| | - Paul McCaughey
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Glasgow, UK
| | - Alexander MacLellan
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Glasgow, UK
| | - Melanie Brewis
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Glasgow, UK
| | - A Colin Church
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Glasgow, UK
| | - Martin K Johnson
- Scottish Pulmonary Vascular Unit, Golden Jubilee National Hospital, Glasgow, UK
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Zaharia L, Hill JM, Loeb E, MacLellan A, Khan A, Hill NO. Systemic lupus erythematosus in twin sisters following ten years of hyperglobulinemic purpura (Waldenström). Acta Med Scand 2009; 199:429-32. [PMID: 1274678 DOI: 10.1111/j.0954-6820.1976.tb06760.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Uniovular twin sisters have been diagnosed 10 years ago as having hyperglobulinemic purpura (Waldenström) at age 12. The diagnosis was documented by purpura of the lower extremities, increased gamma-globulin after serum electrophoresis, and increased 7S component upon ultracentrifugation. In addition, there was an elevated ESR, a positive rheumatoid arthritis latex test, and their LE prep. was negative at that time. At a later date, however, both of them developed polyarthritis. After 9 years for the one and 10 years for the other, their LE prep. became strongly and constantly positive, while their gamma-globulin remained within abnormal limits.
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Clive S, Webb DJ, MacLellan A, Young A, Byrne B, Robson L, Smyth JF, Jodrell DI. Forearm blood flow and local responses to peptide vasodilators: a novel pharmacodynamic measure in the phase I trial of antagonist G, a neuropeptide growth factor antagonist. Clin Cancer Res 2001; 7:3071-8. [PMID: 11595697] [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: 02/21/2023]
Abstract
PURPOSE Arg-D-Trp-NmePhe-D-Trp-Leu-Met-NH(2) (Antagonist G), a substance P (SP 6-11) analogue, inhibits mitogenesis stimulated by a broad spectrum of neuropeptides and has demonstrated antitumor activity in vitro and in vivo with IC(50) concentrations of 10-20 microM in small cell lung cancer and other cell lines. Because neuropeptides are part of complex neurohumoral pathways, we have sought to develop novel pharmacodynamic approaches as part of the early clinical development of this potential anticancer drug. EXPERIMENTAL DESIGN A Phase I trial was performed in two stages. In stage 1, Antagonist G was administered at 3- week intervals using an accelerated dose-escalation strategy until the target maximum plasma concentration (C(max)) of 10 microM was achieved. In stage 2, dose intensity was increased to weekly, and the inhibitory effect of i.v. Antagonist G was assessed by forearm blood flow (FBF) using SP as a vasodilator, as measured by venous plethysmography. RESULTS In stage 1, dose was escalated from 2 to 300 mg/m(2) in 12 dose levels using only 15 patients. In stage 2, nine patients were entered at three dose levels (300, 350, and 400 mg/m(2)) and a C(max) of 45 microM was achieved. Facial flushing was the only consistent toxicity but was not dose limiting. FBF studies demonstrated that Antagonist G consistently inhibited the vasodilatory effects of SP (mean, 62 +/- 2% inhibition). CONCLUSIONS Antagonist G can be safely administered up to 400 mg/m(2), achieving C(max)s >20 microM by weekly 6-h i.v. infusion. FBF studies in patients demonstrated that Antagonist G inhibits SP vasodilatory effects in vivo at these doses in the absence of dose-limiting toxicity.
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Affiliation(s)
- S Clive
- Imperial Cancer Research Fund Medical Oncology Unit, Western General Hospital, University of Edinburgh, Edinburgh EH4 2XU, Scotland, UK
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Jodrell DI, Bowman A, Stewart M, Dunlop N, French R, MacLellan A, Cummings J, Smyth JF. Dose-limiting neurotoxicity in a phase I study of penclomedine (NSC 388720, CRC 88-04), a synthetic alpha-picoline derivative, administered intravenously. Br J Cancer 1998; 77:808-11. [PMID: 9514062 PMCID: PMC2149952 DOI: 10.1038/bjc.1998.131] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [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: 02/06/2023] Open
Abstract
3,5-Dichloro-2,4-dimethoxy-6-(trichloromethyl)pyridine (penclomedine, NSC 338720, CRC 88-04) is an alpha-picoline derivative with anti-tumour activity in preclinical models. Penclomedine administration by 1-h intravenous infusion on 5 consecutive days was repeated 3 weekly in the absence of dose-limiting toxicity (DLT) or disease progression. Five dose levels were investigated (22.5-340 mg m(-2) day[-1]). Eight men and eight women were entered, median age 59 years (range 39-73 years), with good performance status (ECOG 0/1) in 11 patients. A total of 13 out of 16 patients had received previous chemotherapy. Common toxicity criteria grade (CTCg) II vomiting was recorded at all dose levels. Neurotoxicity (cerebellar ataxia and dizziness) was the DLT, CTCg III toxicity occurring in three out of three patients treated at 340 mg m(-2) day(-1). CTCg III dizziness was noted in one out of three patients at 250 mg m(-2) day(-1). Neurotoxicity developed during the 1-h infusion and persisted for a variable period (maximum 5 h) after infusion. Prophylactic antiemetic drugs appeared to reduce associated vomiting but did not prevent ataxia. No antiproliferative toxicities were noted and no anti-tumour responses were documented. Penclomedine pharmacokinetic studies confirmed preclinical evidence of extensive apparent distribution (93 l m[-2]) and rapid clearance (41 l h[-1] m[-2]). Purkinje cell loss has been identified in preclinical models after intraperitoneal administration (O'Reilly et al, 1996a) and further clinical development of penclomedine will focus on oral administration.
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Affiliation(s)
- D I Jodrell
- ICRF Medical Oncology Unit, Western General Hospital, Edinburgh
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Malcolm GP, Jodrell DI, MacLellan A, Swaroop GR, Kelly PA, Whittle IR. Effects of nitric oxide manipulation on the disposition of platinum in an experimental glioma model. Neuroreport 1998; 9:181-5. [PMID: 9507952 DOI: 10.1097/00001756-199801260-00002] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Rodents with striatal C6 glioma were given carboplatin (65 mg kg(-1) in a 10 mg ml(-1) solution, i.v.) after pretreatment with the NO modulating agents 3-morpholinosydnonimine (SIN-1), NG-nitro-L-arginine methyl ester (L-NAME), bradykinin or dexamethasone, to determine whether platinum disposition in the glioma and normal brain was altered. There was no significant change in mean glioma platinum disposition after 3 days of dexamethasone (32+/-9.7 microg/g). Treatment with SIN-1 (45.1+/-14.2 microg/g), L-NAME (42.9+/-4.9 microg/g) and bradykinin (45.7+/-11.3 microg/g) all resulted in increased tumour platinum concentration compared with controls (29+/-5.5 microg/g) but these results were not statistically significant. Dexamethasone significantly (p < 0.05) reduced the platinum concentration in normal brain but the other agents had no effect. Although glioma platinum concentration could be increased by some agents that alter tissue NO levels, the patterns of response were unpredictable and the magnitude (approximately 50%) of the increased platinum disposition is unlikely to be biologically significant.
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Affiliation(s)
- G P Malcolm
- Department of Clinical Neurosciences, University of Edinburgh, Western General Hospital, UK
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Jones DA, Cummings J, Langdon SP, MacLellan A, Smyth JF. Characterization of the deamidase enzyme responsible for the metabolism of the anticancer peptide: H-Arg-D-Trp-NmePhe-D-Trp-Leu-Met-NH2. Biochem Pharmacol 1995; 50:585-90. [PMID: 7669060 DOI: 10.1016/0006-2952(95)00191-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [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
H-Arg-D-Trp-NmePhe-D-Trp-Leu-Met-NH2, a broad spectrum neuropeptide growth factor antagonist (antagonist G), is soon to enter a phase I clinical trial for the treatment of small-cell lung cancer (SCLC). The pre-clinical pharmacology of this peptide has revealed that its metabolism proceeds from the C-terminus via deamidation. In this study the class of enzyme responsible for the degradation of antagonist G has been characterized. Tissue distribution studies on the enzyme have shown it to be very widespread with high specific activity being detected in the spleen, kidney, H69 SCLC xenograft and liver (12.64, 9.58, 8.00 and 6.94 nmols G/mg protein/hr, respectively). HPLC gel filtration indicated that the G-deamidase enzyme had an apparent molecular mass of 81 kDa. The sub-cellular distribution of the enzyme using differential centrifugation indicates that it is largely soluble with > 85% of the activity located in the cytosolic fraction. The distribution of activity towards antagonist G closely resembles that of esterase and acid carboxypeptidase activity, two activities, along with deamidase activity, known to be possessed by serine carboxypeptidases. Studies using a range of protease inhibitors showed clear inhibition of metabolism by phenylmethylsulphonylfluoride and benzyloxycarbonylphenylalanine chloromethylketone, indicating that the enzyme is a chymotrypsin-like serine carboxypeptidase. This knowledge of the enzyme will be invaluable in the further development of antagonist G and similar compounds. Moreover, the widespread distribution of this enzyme together with its broad specificity for C-terminal group suggests that it should be given serious consideration when designing C-terminally modified peptide drugs.
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Affiliation(s)
- D A Jones
- Imperial Cancer Research Fund, Medical Oncology Unit, Western General Hospital, Edinburgh, U.K
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Cummings J, MacLellan A, Langdon SP, Smyth JF. Stability and in vitro metabolism of the mitogenic neuropeptide antagonists [D-Arg1,D-Phe5, D-Trp7,9, Leu11]-substance P and [Arg6, D-Trp7,9, MePhe8]-substance P (6-11) characterized by high-performance liquid chromatography. J Pharm Biomed Anal 1994; 12:811-9. [PMID: 7522585 DOI: 10.1016/0731-7085(93)e0027-k] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [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: 01/25/2023]
Abstract
The substance P (SP) analogues [D-Arg1, D-Phe5, D-Trp7,9, Leu11]-SP and [Arg6, D-Trp7,9, MePhe8]-SP (6-11) (antagonists D and G, respectively) are under consideration as new anticancer drugs. In this report, the stability and in vitro metabolism of both antagonists in up to seven different media (water, 1 M acetic acid, human plasma, nude mouse liver and WX 322 human SCLC xenograft homogenized in either 1 M acetic acid or phosphate buffered saline (PBS), pH 7.4) have been characterized by both isocratic and gradient elution reversed-phase HPLC. Antagonist D was stable (never > 13% degradation over 24 h, at 37 degrees C) in water, 1 M acetic acid and plasma but was metabolized by PBS liver homogenates (10%, w/v) sequentially to two stable metabolites with a half life of 0.98 h at a concentration of 500 micrograms ml-1. The major pathway of degradation of antagonist G appeared to be C-terminal methionine oxidation (particularly in plasma) as well as hydrolysis, with even aqueous solutions being significantly affected at low concentrations of peptide (0.1 micrograms ml-1, half life 20.9 h at 37 degrees C). Stable metabolites of antagonist G were also detected in incubations with PBS liver homogenates (half life 1.53 h at 500 micrograms ml-1, 37 degrees C). Overall, the data presented indicate that the modifications made to SP have been relatively successful in preserving chemical and biological stability.
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Affiliation(s)
- J Cummings
- Imperial Cancer Research Fund, Medical Oncology Unit, Western General Hospital, Edinburgh, UK
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Cummings J, MacLellan A, Langdon SP, Rozengurt E, Smyth JF. Determination of two neuropeptide growth factor antagonists, [D-Arg1,D-Phe5,D-Trp7,9,Leu11]-substance P and [Arg6,D-Trp7,9,N-MePhe8]- substance P(6-11), by high-performance liquid chromatography with electrochemical detection. J Chromatogr B Biomed Appl 1994; 653:195-203. [PMID: 7515751 DOI: 10.1016/0378-4347(93)e0442-s] [Citation(s) in RCA: 14] [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: 01/25/2023]
Abstract
The neuropeptide growth factor antagonists [D-Arg1,D-Phe5,D-Trp7,9,Leu11]-substance P (D) and [Arg6,D-Trp7,9, [corrected] N-MePhe8]-substance P(6-11) (G) are currently undergoing preclinical evaluation as potential anticancer agents and clinical trials are planned for G in the near future. A reversed-phase high-performance liquid chromatographic separation has been developed which is both sensitive (limit of detection 250 pg/263 fmol for G; 500 pg/330 fmol for D) and selective, based on electrochemical detection of the two tryptophan residues present in each peptide. Two ion-pairing agents were included in the isocratic mobile phase to eliminate adsorption of the peptides onto the analytical column. Extensive sample clean-up procedures have been developed for plasma, tissue and tumour based on solid-phase extraction. Precision and accuracy of each assay was 91.3 +/- 16.9% (between-day) for G and 99.3 +/- 16.9% (between-day) for D. The assays were able to detect the intact peptides and a number of their metabolites in plasma, liver and the WX 322 SCLC human xenograft in nude mice for at least 6 hr after administration of therapeutic and pharmacological doses.
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Affiliation(s)
- J Cummings
- Imperial Cancer Research Fund, Western General Hospital, Edinburgh, UK
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Abstract
HPLC has been applied to determine the stability of mechlorethamine hydrochloride (nitrogen mustard) formulated as an ointment in white soft paraffin (10 mg drug, 50 g paraffin and 1 mL acetone). A new solubilization technique is described for extraction of the drug from the ointment for HPLC analysis which has an extraction efficiency of 76.1% with a coefficient of variation of 10.4%. Stored at 4 degrees C the drug content of the ointment remained stable for at least 84 days and stored at 37 degrees C the drug content remained stable for at least 40 days. In comparison aqueous solutions of mechlorethamine at the same concentration, fully degraded after 4 days. These data will aid hospital pharmacists decide on a standardized protocol for the controlled usage of the ointment which is both safe and cost-effective.
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Affiliation(s)
- J Cummings
- Imperial Cancer Research Fund, Medical Oncology Unit, Western General Hospital, Edinburgh, UK
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French RC, Cummings J, MacLellan A, MacPherson JS, Ritchie AA, Smyth JF. The comparative disposition of the pyrolloquinone GR63178A and its 9-hydroxy metabolite GR54374X in sensitive and resistant mouse colon adenocarcinoma. Cancer Chemother Pharmacol 1993; 32:156-61. [PMID: 8485810 DOI: 10.1007/bf00685620] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The novel anticancer compound GR63178A is being evaluated in the clinic, having demonstrated activity against a wide range of experimental tumour systems in animals without significant toxic side-effects being apparent. In this work, we have demonstrated significant antitumour action of this compound against one murine colon cancer model (colon 38 tumour in BDF-1 mice, specific growth delay = 1.2) when given at 10 mg/kg over 21 consecutive days and in contrast shown minimal sensitivity of another similar murine colon adenocarcinoma, MAC 26, in NMRI mice with the same dose regime. We investigated the disposition of both the parent drug and the 9-OH metabolite (GR54374X) in plasma, tissues and tumours, using solid phase extraction followed by reversed-phase high performance liquid chromatography. Although plasma clearance profiles of GR63178A were similar, significant differences were seen in the disposition of the drug to major organs in two mouse strains. Noteably, the liver and kidneys of the sensitive model had higher levels of parent drug and 9-OH metabolite at both 30 min and 4 h post-injection. However, this was not apparent in the tumours themselves, and the levels of 9-OH metabolite were lower in the plasma and higher in the urine of the sensitive mice, indicating possible rapid renal clearance of this compound. Neither GR63178A nor GR54374X proved cytotoxic in in vitro experiments. The data presented here have revealed considerable variation in drug handling by these two mouse strains, but this did not produce different levels of either parent drug or GR54374X in the tumours, which are the presumed targets, suggesting that differences in disposition are probably not responsible for the different sensitivities of the two tumours. Other possible explanations include the production of a hitherto undetected ultimate cytotoxic metabolite in the sensitive, but not in the resistant, mouse/tumour combination, or differences in inherent tumour sensitivity, or in host-mediated effects. These possibilities are discussed.
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Affiliation(s)
- R C French
- Imperial Cancer Research Fund, Medical Oncology Unit, Western General Hospital, Edinburgh, UK
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Cummings J, MacLellan A, Smyth JF, Farmer PB. Determination of reactive nitrogen mustard anticancer drugs in plasma by high-performance liquid chromatography using derivatization. Anal Chem 1991; 63:1514-9. [PMID: 1952082 DOI: 10.1021/ac00015a004] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [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: 12/29/2022]
Abstract
A high-performance liquid chromatography (HPLC) method is described for the determination of reactive nitrogen mustard anticancer drugs in plasma after derivatization with diethyl-dithiocarbamic acid (DDTC). Three compounds were studied: two reactive species (mechlorethamine (HN2) and galactose 6-mustard (G-6-M] and a less reactive species (melphalan (L-PAM] included for validation experiments. Mass and NMR spectrometry confirmed that one molecule of DDTC reacts with each arm of the mustard, displacing a chlorine atom to form a stable disubstituted adduct. With the reactive mustards a 30-min incubation at 37 degrees C is recommended for greater than 90% derivatization efficiency. Gradient elution was employed to analyze all three compounds using the same conditions with a microBondapak C18 10-microns particle size column (30 cm by 3.8 mm i.d.). The retention time (tR) of HN2-DDTC2 was 13.1 min +/- 1.5% within day CV; tR of L-PAM was 7.6 min and L-PAM-DDTC2 was 14.6 min +/- 0.8% CV. G-6-M-DDTC2 yielded a double peak, tR = 10.7 min and 10.9 min +/- 2.9% CV. The limit of detection on column was 0.5 ng for HN2, 1 ng for L-PAM, and 5 ng for G-6-M. A solid-phase sample preparation technique using "Bond Elut" phenyl is described that extracts from plasma G-6-M-DDTC2 with greater than 74% efficiency and HN2-DDTC2 with greater than 90% efficiency. When the drugs were derivatized in plasma, recovery remained high for G-6-M (greater than 84%) but dropped to 50% for HN2.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J Cummings
- Imperial Cancer Research Fund, Medical Oncology Unit, Western General Hospital, Edinburgh, U.K
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Cummings J, French RC, MacLellan A, Smyth JF. Chromatographic characterisation of six human metabolites of the new anticancer drug GR63178A. Cancer Chemother Pharmacol 1991; 28:27-32. [PMID: 2040030 DOI: 10.1007/bf00684952] [Citation(s) in RCA: 4] [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: 12/29/2022]
Abstract
GR63178A is the second pentacyclic pyrroloquinone to enter clinical trials as an anticancer drug. We developed a reversed-phase, gradient-elution high-performance liquid chromatography (HPLC) method along with a Bond Elut C2 mini-column sample-preparation technique for the analysis of GR63178A, its 9-hydroxy-metabolite GR54374X and internal standard GR70440A in human plasma and urine. The limit of detection is 2 ng/ml for both GR63178A and GR54374X. Analysis of GR63178A is complicated by its light instability, whereby a number of chromatographically distinct, stable degradation products can form. These can be practically eliminated if clinical specimens are frozen immediately and all subsequent sample preparation is performed in a darkroom. Using this methodology, a total of six metabolites (including GR54374X) were detected in human plasma and urine specimens. The five new metabolites were characterised according to polarity (HPLC retention time), UV-visible absorption maxima and the effect of incubation with beta-glucuronidase and aryl-sulphatase. Application of this methodology to the analysis of GR63178A will aid in the development of this novel synthetic anticancer drug.
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Affiliation(s)
- J Cummings
- Medical Oncology Unit, Western General Hospital, Edinburgh, UK
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Khan A, Hill JM, Grater W, Loeb E, MacLellan A, Hill N. Atopic hypersensitivity to cis-dichlorodiammineplatinum(II) and other platinum complexes. Cancer Res 1975; 35:2766-70. [PMID: 50881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Allergic reaction to an antitumor agent, cis-dichlorodiammineplatinum(II) (DDP) was investigated. A 15-year-old white male with pulmonary metastases from embryonal carcinoma of testis was treated with a combination of DDP, bleomycin, and vinblastine. The dose of DDP varied from 2 to 2.25 mg/kg given i.v. He received 7 doses of DDP in 9 months. An anaphylactic reaction was seen within 3 min of the initiation of i.v. infusion of the 8th dose of DDP. The reaction was due to atopic hypersensitivity, as confirmed by an immediate wheal and flair reaction and increased histamine release from leukocytes with DDP. His serum IgE level was elevated. Neither the presence of chloride nor the amine grouping in DDP was essential for reactivity. The replacement of platinum with palladium abrogated the reactivity. There was no cross-reactivity with 3 other platinum complexes of known antitumor activity (platinum blue, platinum(II) 1,2-diaminocyclohexane malonate, and platinum(II) ethylenediamine malonate). This was also confirmed by the lack of reaction to subsequent i.v. administration of platinum(II) 1,2-diaminocyclohexane malonate (10 mg/kg) in this patient.
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Khan A, Hill JM, MacLellan A, Loeb E, Hill NO, Thaxton S. Improvement in delayed hypersensitivity in Hodgkin's disease with transfer factor: lymphapheresis and cellular immune reactions or normal donors. Cancer 1975; 36:86-9. [PMID: 1081903 DOI: 10.1002/1097-0142(197507)36:1<86::aid-cncr2820360103>3.0.co;2-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Passive transfer of delayed hypersensitivity was achieved, with normal transfer factor, in patients with Hodgkin's disease in remission. The cellular immune responses of the recipients improved. It is suggested that, in addition to specific effect the transfer factor (or factors) has a nonspecific effect causing improvement in the state of delayed hypersensitivity of the recipient in general. The average number of E-rosette T lymphocytes was 46.3% after the transfer factor treatment in Hodgkin's disease. The control patients with Hodgkin's disease, not receiving transfer factor, had a value of 37.8%. Removal of 4.9 X 10(9) to 1.08 X 10(10) lymphocytes did not diminish the delayed hypersensitivity of the donor. Side effects attributable to transfer factor were not seen.
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Hill JM, Loeb E, MacLellan A, Hill NO, Khan A, King JJ. Clinical studies of Platinum Coordination compounds in the treatment of various malignant diseases. Cancer Chemother Rep 1975; 59:647-59. [PMID: 1203889] [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: 12/26/2022]
Abstract
Following the prior work of Rosenberg et al, Rosenberg and VanCamp, and Speer et al, we started clinical trials with cis-dichlorodiammineplatinum(II) in April 1971. Marked tumor regression was noted in several malignant diseases in these initial clinical studies which were reported at the Chemotherapy Congress in Prague, August 1971. At the present time over 178 patients have been treated wihhis durg for a variety of malignant conditions. Approximately half of these patients received the platinum compound alone and the other half received it in combination with four other chemotherapeutic agents...
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Hill JM, Loeb E, MacLellan A, Khan A, Roberts J, Shields WF, Hill NO. Response to highly purified L-asparaginase during therapy of acute leukemia. Cancer Res 1969; 29:1574-80. [PMID: 4896902] [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: 01/12/2023]
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