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Dive into the research topics where Dayalan Karat is active.

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Featured researches published by Dayalan Karat.


British Journal of Surgery | 2005

Sentinel node biopsy to evaluate the metastatic dissemination of oesophageal adenocarcinoma

P. J. Lamb; S. M. Griffin; Alastair D. Burt; J. J. Lloyd; Dayalan Karat; N Hayes

The aim of this study was to determine the feasibility and accuracy of sentinel lymph node (SLN) biopsy for oesophageal adenocarcinoma.


British Journal of Surgery | 2004

Prospective study of routine contrast radiology after total gastrectomy

P. J. Lamb; S. M. Griffin; M. V. Chandrashekar; David Richardson; Dayalan Karat; N. Hayes

The practice of routine contrast radiology before recommencing oral nutrition after total gastrectomy is not evidence based. The aim of this prospective study was to evaluate the clinical role and timing of this investigation.


Surgical Endoscopy and Other Interventional Techniques | 2006

Use of alarm symptoms to select dyspeptics for endoscopy causes patients with curable esophagogastric cancer to be overlooked

D. J. Bowrey; S. M. Griffin; J. Wayman; Dayalan Karat; N Hayes; S. A. Raimes

BackgroundIn August 2004, the United Kingdom Department of Health advisory body published dyspepsia referral guidelines for primary care practitioners. These guidelines advised empiric treatment with antisecretory medications and referral for endoscopy only in the presence of alarm symptoms. The current study aimed to evaluate the effect of these guidelines on the detection of esophagogastric cancer.MethodsThe study reviewed a prospectively compiled database of 4,018 subjects who underwent open access gastroscopy during the years 1990 to 1998. The main outcome measures for the study were cancer detection rates, International Union Against Cancer (UICC) stage, and survival.ResultsGastroscopy identified esophagogastric carcinoma in 123 (3%) of the 4,018 subjects. Of these 123 patients, 104 (85%) with esophagogastric cancer had “alarm” symptoms (anemia, mass, dysphagia, weight loss, vomiting) and would have satisfied the referral criteria. The remaining 15% would not have been referred for initial endoscopic assessment because their symptoms were those of uncomplicated “benign” dyspepsia. The patients with “alarm” symptoms had a significantly more advanced tumor stage (metastatic disease in 47% vs 11%; p < 0.001), were less likely to undergo surgical resection (50% vs 95%; p < 0.001), and had a poorer survival (median, 11 vs 39 months; p = 0.01) than their counterparts without such symptoms.ConclusionsThe use of alarm symptoms to select dyspeptics for endoscopy identifies patients with advanced and usually incurable esophagogastric cancer. Patients with early curable cancers often have only dyspeptic symptoms, and their diagnosis will be delayed until the symptoms of advanced cancer develop.


Lancet Neurology | 2015

Safety and efficacy of diaphragm pacing in patients with respiratory insufficiency due to amyotrophic lateral sclerosis (DiPALS): a multicentre, open-label, randomised controlled trial.

Christopher J McDermott; Mike Bradburn; Chin Maguire; Cindy Cooper; Wendy Baird; Susan Baxter; Stephen C Bourke; I Imam; Andrew Bentley; John Ealing; M Elliott; C O Hanemann; P Hughes; Richard W. Orrell; Pamela J. Shaw; Kevin Talbot; Tim Williams; Roger Ackroyd; R Berrisford; Simon Galloway; Dayalan Karat; Nick Maynard; A Sarela; L Taylor; Russell Leek; R Darlison; Nigel Leigh; M Dewey; A Radunovic

BACKGROUND Non-invasive ventilation is part of the standard of care for treatment of respiratory failure in patients with amyotrophic lateral sclerosis (ALS). The NeuRx RA/4 Diaphragm Pacing System has received Humanitarian Device Exemption approval from the US Food and Drug Administration for treatment of respiratory failure in patients with ALS. We aimed to establish the safety and efficacy of diaphragm pacing with this system in patients with respiratory muscle weakness due to ALS. METHODS We undertook a multicentre, open-label, randomised controlled trial at seven specialist ALS and respiratory centres in the UK. Eligible participants were aged 18 years or older with laboratory supported probable, clinically probable, or clinically definite ALS; stable riluzole treatment for at least 30 days; and respiratory insufficiency. We randomly assigned participants (1:1), via a centralised web-based randomisation system with minimisation that balanced patients for age, sex, forced vital capacity, and bulbar function, to receive either non-invasive ventilation plus pacing with the NeuRx RA/4 Diaphragm Pacing System or non-invasive ventilation alone. Patients, carers, and outcome assessors were not masked to treatment allocation. The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Analysis was by intention to treat. This trial is registered, ISRCTN number 53817913. FINDINGS Between Dec 5, 2011, and Dec 18, 2013, we randomly assigned 74 participants to receive either non-invasive ventilation alone (n=37) or non-invasive ventilation plus diaphragm pacing (n=37). On Dec 18, 2013, the Data Monitoring and Ethics Committee (DMEC) recommended suspension of recruitment on the basis of overall survival figures. Randomly assigned participants continued as per the study protocol until June 23, 2014, when the DMEC advised discontinuation of pacing in all patients. Follow-up assessments continued until the planned end of the study in December, 2014. Survival was shorter in the non-invasive ventilation plus pacing group than in the non-invasive ventilation alone group (median 11·0 months [95% CI 8·3-13·6] vs 22·5 months [13·6-not reached]; adjusted hazard ratio 2·27, 95% CI 1·22-4·25; p=0·009). 28 (76%) patients died in the pacing group and 19 (51%) patients died in the non-invasive ventilation alone group. We recorded 162 adverse events (5·9 events per person-year) in the pacing group, of which 46 events were serious, compared with 81 events (2·5 events per person-year) in the non-invasive ventilation alone group, of which 31 events were serious. INTERPRETATION Addition of diaphragm pacing to standard care with non-invasive ventilation was associated with decreased survival in patients with ALS. Our results suggest that diaphragmatic pacing should not be used as a routine treatment for patients with ALS in respiratory failure. FUNDING The National Institute for Health Research Health Technology Assessment Programme; the Motor Neurone Disease Association of England, Wales, and Northern Ireland.


European Respiratory Journal | 2012

Anti-reflux surgery in lung transplant recipients: outcomes and effects on quality of life

Agn Robertson; A. Krishnan; Christopher Ward; Jeffrey P. Pearson; Therese Small; Pa Corris; John H. Dark; Dayalan Karat; Jonathan Shenfine; S. M. Griffin

Fundoplication may improve survival after lung transplantation. Little is known about the effects of fundoplication on quality of life in these patients. The aim of this study was to assess the safety of fundoplication in lung transplant recipients and its effects on quality of life. Between June 1, 2008 and December 31, 2010, a prospective study of lung transplant recipients undergoing fundoplication was undertaken. Quality of life was assessed before and after surgery. Body mass index (BMI) and pulmonary function were followed up. 16 patients, mean±sd age 38±11.9 yrs, underwent laparoscopic Nissen fundoplication. There was no peri-operative mortality or major complications. Mean±sd hospital stay was 2.6±0.9 days. 15 out of 16 patients were satisfied with the results of surgery post fundoplication. There was a significant improvement in reflux symptom index and DeMeester questionnaires and gastrointestinal quality of life index scores at 6 months. Mean BMI decreased significantly after fundoplication (p=0.01). Patients operated on for deteriorating lung function had a statistically significant decrease in the rate of lung function decline after fundoplication (p=0.008). Laparoscopic fundoplication is safe in selected lung transplant recipients. Patient benefit is suggested by improved symptoms and satisfaction. This procedure is acceptable, improves quality of life and may reduce deterioration of lung function.


British Journal of Cancer | 1999

Expression of oestrogen and progesterone receptors in gastric cancer: a flow cytometric study

Dayalan Karat; I Brotherick; B K Shenton; D Scott; S. A. Raimes; S. M. Griffin

SummaryIncreased expression of oestrogen (ER) and progesterone (PR) receptors have been reported in gastric adenocarcinoma, although results have been variable. Immunohistochemical staining methodologies, in particular in the detection of ER, have been inconsistent with many tumours being classified ER-negative. In this study we have used flow cytometry to quantify expression of ER and PR in gastric adenocarcinoma and examine their relationships with established prognostic indicators. Cytokeratin-positive cells obtained from tumour biopsies of 50 patients with gastric cancer and ten control patients were labelled with biotinylated ER or PR antibodies followed by streptavidin PE. Flow cytometry was seen to increase the detection of ER levels in gastric cancer with more receptor-positive patients in this study than in results published to date. We believe this is related to the sensitivity of the flow cytometric assay with the detection of small shifts in ER level detected using cytokeratin gating. On analysis, the data showed no significant correlations with tumour stage and grade, and no differences were seen between normal mucosa and gastric cancer samples.


British Journal of Surgery | 2008

Iatrogenic perforation of localized oesophageal cancer.

F. Di Franco; P. J. Lamb; Dayalan Karat; N. Hayes; S. M. Griffin

The incidence of iatrogenic perforation of oesophageal cancer has increased in parallel with the use of therapeutic dilatation to relieve dysphagia and allow full endoscopic staging and evaluation by endoscopic ultrasonography1. The management remains controversial, with both urgent surgical resection2 and conservative treatment3 being advocated. Although definitive treatment is influenced by the stage of disease and patient fitness, the potential dissemination of malignant cells at perforation raises the question whether oesophagectomy is appropriate even for those with initially resectable disease. The aim of this study was to evaluate early clinical outcome and survival after oesophagectomy and non-operative management of patients with iatrogenic perforation of oesophageal carcinoma in a specialist unit.


Health Technology Assessment | 2016

DiPALS: Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis - a randomised controlled trial.

Christopher J McDermott; Mike Bradburn; Chin Maguire; Cindy Cooper; Wendy Baird; Susan Baxter; Judith Cohen; Hannah Cantrill; Simon Dixon; Roger Ackroyd; Simon Baudouin; Andrew Bentley; R Berrisford; Stephen Bianchi; Stephen C Bourke; R Darlison; John Ealing; Mark Elliott; Patrick Fitzgerald; Simon Galloway; H Hamdalla; C O Hanemann; Philip Hughes; I Imam; Dayalan Karat; Russell Leek; Nick Maynard; Richard W. Orrell; A Sarela; John Stradling

BACKGROUND Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease resulting in death, usually from respiratory failure, within 2-3 years of symptom onset. Non-invasive ventilation (NIV) is a treatment that when given to patients in respiratory failure leads to improved survival and quality of life. Diaphragm pacing (DP), using the NeuRx/4(®) diaphragm pacing system (DPS)™ (Synapse Biomedical, Oberlin, OH, USA), is a new technique that may offer additional or alternative benefits to patients with ALS who are in respiratory failure. OBJECTIVE The Diaphragm Pacing in patients with Amyotrophic Lateral Sclerosis (DiPALS) trial evaluated the effect of DP on survival over the study duration in patients with ALS with respiratory failure. DESIGN The DiPALS trial was a multicentre, parallel-group, open-label, randomised controlled trial incorporating health economic analyses and a qualitative longitudinal substudy. PARTICIPANTS Eligible participants had a diagnosis of ALS (ALS laboratory-supported probable, clinically probable or clinically definite according to the World Federation of Neurology revised El Escorial criteria), had been stabilised on riluzole for 30 days, were aged ≥ 18 years and were in respiratory failure. We planned to recruit 108 patients from seven UK-based specialist ALS or respiratory centres. Allocation was performed using 1 : 1 non-deterministic minimisation. INTERVENTIONS Participants were randomised to either standard care (NIV alone) or standard care (NIV) plus DP using the NeuRX/4 DPS. MAIN OUTCOME MEASURES The primary outcome was overall survival, defined as the time from randomisation to death from any cause. Secondary outcomes were patient quality of life [assessed by European Quality of Life-5 Dimensions, three levels (EQ-5D-3L), Short Form questionnaire-36 items and Sleep Apnoea Quality of Life Index questionnaire]; carer quality of life (EQ-5D-3L and Caregiver Burden Inventory); cost-utility analysis and health-care resource use; tolerability and adverse events. Acceptability and attitudes to DP were assessed in a qualitative substudy. RESULTS In total, 74 participants were randomised into the trial and analysed, 37 participants to NIV plus pacing and 37 to standard care, before the Data Monitoring and Ethics Committee advised initial suspension of recruitment (December 2013) and subsequent discontinuation of pacing (on safety grounds) in all patients (June 2014). Follow-up assessments continued until the planned end of the study in December 2014. The median survival (interquartile range) was 22.5 months (lower quartile 11.8 months; upper quartile not reached) in the NIV arm and 11.0 months (6.7 to 17.0 months) in the NIV plus pacing arm, with an adjusted hazard ratio of 2.27 (95% confidence interval 1.22 to 4.25; p = 0.01). CONCLUSIONS Diaphragmatic pacing should not be used as a routine treatment for patients with ALS in respiratory failure. FUTURE WORK It may be that certain population subgroups benefit from DP. We are unable to explain the mechanism behind the excess mortality in the pacing arm, something the small trial size cannot help address. Future research should investigate the mechanism by which harm or benefit occurs further. TRIAL REGISTRATION Current Controlled Trials ISRCTN53817913. FUNDING This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 20, No. 45. See the HTA programme website for further project information. Additional funding was provided by the Motor Neurone Disease Association of England, Wales and Northern Ireland.


BMC Neurology | 2012

Protocol for diaphragm pacing in patients with respiratory muscle weakness due to motor neurone disease (DiPALS): a randomised controlled trial.

Christopher J McDermott; Chin Maguire; Cindy Cooper; Roger Ackroyd; Wendy Baird; Simon Baudouin; Andrew Bentley; Stephen Bianchi; Stephen C Bourke; Mike Bradburn; Simon Dixon; John Ealing; Simon Galloway; Dayalan Karat; Nick Maynard; Karen E. Morrison; Naveed Mustfa; John Stradling; Kevin Talbot; Tim Williams; Pamela J. Shaw

BackgroundMotor neurone disease (MND) is a devastating illness which leads to muscle weakness and death, usually within 2-3 years of symptom onset. Respiratory insufficiency is a common cause of morbidity, particularly in later stages of MND and respiratory complications are the leading cause of mortality in MND patients. Non Invasive Ventilation (NIV) is the current standard therapy to manage respiratory insufficiency. Some MND patients however do not tolerate NIV due to a number of issues including mask interface problems and claustrophobia. In those that do tolerate NIV, eventually respiratory muscle weakness will progress to a point at which intermittent/overnight NIV is ineffective. The NeuRx RA/4 Diaphragm Pacing System was originally developed for patients with respiratory insufficiency and diaphragm paralysis secondary to stable high spinal cord injuries. The DiPALS study will assess the effect of diaphragm pacing (DP) when used to treat patients with MND and respiratory insufficiency.Method/Design108 patients will be recruited to the study at 5 sites in the UK. Patients will be randomised to either receive NIV (current standard care) or receive DP in addition to NIV. Study participants will be required to complete outcome measures at 5 follow up time points (2, 3, 6, 9 and 12 months) plus an additional surgery and 1 week post operative visit for those in the DP group. 12 patients (and their carers) from the DP group will also be asked to complete 2 qualitative interviews.DiscussionThe primary objective of this trial will be to evaluate the effect of Diaphragm Pacing (DP) on survival over the study duration in patients with MND with respiratory muscle weakness. The project is funded by the National Institute for Health Research, Health Technology Assessment (HTA) Programme (project number 09/55/33) and the Motor Neurone Disease Association and the Henry Smith Charity. Trial Registration: Current controlled trials ISRCTN53817913. The views and opinions expressed therein are those of the authors and do not necessarily reflect those of the HTA programme, NIHR, NHS or the Department of Health.


British Journal of Surgery | 2008

Randomized clinical trial of laparoscopic total (Nissen) versus posterior partial (Toupet) fundoplication for gastro-oesophageal reflux disease based on preoperative oesophageal manometry (Br J Surg 2008; 95: 57–63)

Andrew G.N. Robertson; Lorna J. Dunn; Jonathan Shenfine; Dayalan Karat; S. M. Griffin

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses should be sent electronically via the BJS website (www.bjs.co.uk). All letters will be reviewed and,if approved,appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length. Copyright

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Chin Maguire

University of Sheffield

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Wendy Baird

University of Sheffield

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Andrew Bentley

University of Manchester

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John Ealing

Salford Royal NHS Foundation Trust

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Roger Ackroyd

Northern General Hospital

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Stephen C Bourke

Northumbria Healthcare NHS Foundation Trust

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Simon Dixon

University of Sheffield

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Susan Baxter

University of Sheffield

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