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Fetz A, Li L, Lee C, Leung L. A253 PRIMARY PROPHYLAXIS FOR SPONTANEOUS BACTERIAL PERITONITIS IN HOSPITALIZED CIRRHOTIC PATIENTS WITH LOW PROTEIN ASCITES AND RENAL DYSFUNCTION OR LIVER FAILURE: A RETROSPECTIVE REVIEW FROM A TERTIARY CENTRE IN BRITISH COLUMBIA. J Can Assoc Gastroenterol 2023. [PMCID: PMC9991183 DOI: 10.1093/jcag/gwac036.253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/09/2023] Open
Abstract
Background Spontaneous bacterial peritonitis (SBP) is a severe and often fatal infection that can occur in patients with cirrhosis and ascites. The benefits of primary prophylaxis with antibiotics for SBP have been demonstrated in patients with cirrhosis presenting with gastrointestinal (GI) bleeding; patients hospitalized for other reasons with an ascitic protein less than 10 g/L; and patients with ascitic protein less than 15 g/L with either impaired renal function (serum creatinine greater than 106 µmol/L, BUN greater than 8.9 mmol/L, or serum sodium less than or equal to 130 mEq/L) or liver failure (Child-Pugh score greater than or equal to 9 or bilirubin greater than 50 umol/L). Purpose To evaluate the rate of primary prophylaxis in patients discharged from a tertiary care hospital with low protein ascites and impaired renal function or liver failure, and subsequent episodes of SBP, hospitalizations, or deaths. Method A retrospective chart review at St. Paul’s Hospital in Vancouver, British Columbia, from November 2019 to August 2021 was conducted. Hospitalized patients with cirrhosis who had an ascitic protein less than 15 g/L and met criteria for either renal dysfunction or liver failure were included in the study. The rate of primary prophylaxis prescribed in eligible patients as well as the subsequent incidence of SBP, hospitalizations, or all-cause mortality were evaluated. Patients were followed up to 12 months after the index paracentesis. Result(s) A total of 279 patients with cirrhosis were hospitalized during the study period. 69 patients underwent a diagnostic paracentesis and 41 patients met the inclusion criteria for primary SBP prophylaxis. 28 patients were excluded with most common reasons being ascitic protein above 15 g/L (n=12), no documented ascitic protein concentration (n=9), or index paracentesis met the criteria for the diagnosis of SBP (n=5). Of the patients included, 37 (90.2%) did not receive primary prophylaxis. 8 of these patients (21.6%) developed subsequent SBP. 30 patients (81.1%) were hospitalized at least once in the following 12 months. 18 (48.6%) died during the follow-up period with 1 death attributed to SBP. 4 patients (9.76%) received primary prophylaxis and were prescribed either ciprofloxacin or trimethoprim/sulfamethoxazole. None of these patients developed SBP, however, 3 (75%) were hospitalized and died from other causes. Conclusion(s) The rate of primary prophylaxis for SBP in hospitalized patients with low protein ascites and impaired renal function or liver failure at our institution is low. The guarded prognosis in this subset of patients is also demonstrated. Further studies are needed to assess the root causes for the lack of primary prophylaxis given. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared
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Affiliation(s)
- A Fetz
- University of British Columbia, Vancouver, Canada
| | - L Li
- University of British Columbia, Vancouver, Canada
| | - C Lee
- University of British Columbia, Vancouver, Canada
| | - L Leung
- University of British Columbia, Vancouver, Canada
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Akhtar Z, Sohal M, Kontogiannis C, Leung LWM, Harding I, Zuberi Z, Bajpai A, Norman M, Pearse S, Beeton I, Gallagher MM. Anatomical variations in coronary venous drainage: challenges and solutions in delivering cardiac resynchronisation therapy. Europace 2022. [DOI: 10.1093/europace/euac053.490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Cardiac resynchronisation therapy (CRT) is the cornerstone of heart failure management. Delivery of a left ventricular lead can occur in a small proportion of patients undermining the benefits of this treatment. Abnormal coronary venous anatomy is a contributing factor to this failure. Although epicardial lead placement is available, this patient cohort requiring CRT is subject to higher peri-operative morbidity and mortality than the general population; a transvenous approach is preferable.
Purpose
To investigate the abnormalities of the coronary venous system in candidates for cardiac resynchronization therapy (CRT) and describe methods for circumventing the resulting difficulties.
Methods
From 4 implanting institutes, data of all CRT implants between October 2008-October 2020 were screened for abnormal cardiac venous anatomy, defined as an anatomical variation not conforming to the accepted ‘normal’ anatomy. Patient demographics, procedural detail and subsequent left ventricle (LV) lead pacing indices were collected.
Results
From a total of 3548 CRT implants, 15 (0.42%) patients (80% male) of 72.2±10.6 years in age with a LV ejection fraction of 34±10.3% were identified to have had an abnormal cardiac venous anatomy over the study period. There were 13 cases of persistent left side superior vena cava (pLSVC), 5 of which had coronary sinus ostium atresia (CSOA) including 2 with an ‘unroofed’ coronary sinus (CS); 1 patient had a unique anomalous origin of the CS and 1 patient had an isolated CSOA. In total 14 patients (60% repeat attempt) had successful percutaneous implant under general anaesthesia (46.7%) via the cephalic vein (59.1%), using the femoral approach (53.3%) for levophase venography and/or pull-through, including 1 case of endocardial LV implant. Pacing follow-up over 37.64±37.6 months demonstrated LV lead threshold between 0.62-2.9 volts (pulsewidth 0.4-1.5 milliseconds) in all cases; 5 patients died within 2.92±1.6 years of successful implant.
Conclusion
CRT devices can be implanted percutaneously even in the presence of substantial abnormalities of coronary venous anatomy. Alternative routes of venous access may be required.
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Affiliation(s)
- Z Akhtar
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - M Sohal
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - C Kontogiannis
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - LWM Leung
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - I Harding
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - Z Zuberi
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - A Bajpai
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - M Norman
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - S Pearse
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - I Beeton
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - MM Gallagher
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
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Akhtar Z, Zuberi Z, Leung LWM, Kontogiannis C, Waleed K, Elbatran AI, Sohal M, Gallagher MM. Transvenous lead extraction: the Tandem approach. Europace 2022. [DOI: 10.1093/europace/euac053.535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Transvenous lead extraction (TLE) has become an important strategy in the management of patients with cardiac implantable electronic devices (CIEDs). A rising population of patients with CIEDs coupled with an expanding indication for TLE, has fuelled demand. There are notable procedural risks however development of techniques and tools have contributed to an improvement in the safety and efficacy of TLE. The mechanical rotational dissecting sheath is safe and efficacious whilst the Needle’s Eye Snare (NES) is an additional ‘bail-out’ strategy contributing to procedural success.
Purpose
We sought to evaluate the outcomes of TLE performed from the superior access in conjunction with counter-traction provided by snaring of the targeted lead via the femoral access.
Method
The ‘Tandem’ procedure consisted of the rotational powered sheath performing dissection of the adhesions encapsulating the leads (at the superior access), in ‘Tandem’ with the Needle’s Eye Snare providing countertraction via the femoral vein. In brief: after deployment of the locking stylet in the lead lumen, the NES was used to grasp the lead in the right atrium and hold it tort while a rotational sheath was used to dissect through the veins. Once the sheath reached the right atrium, the lead was released from the snare and the sheath was used to continue dissection toward the lead tip. Data for all consecutive ‘Tandem’ procedures performed between 1/1/2021 – 1/1/2022 in our high-volume TLE institute were collected and evaluated for safety and efficacy.
Results
Forty patients aged 69.2±16.3 (70% male), underwent TLE of 75 leads (45 right ventricle, 25, right atrium, 5 left ventricle) with dwell time of 150.1±80.3 months for a non-infectious indication (65%). Of the 40 cases, 27 were hypertensives, 14 had ischaemic heart disease whilst 5 suffered diabetes with a left ventricle ejection fraction of 46.8±10.2%; 12 (30%) were pacing dependent. Procedures were performed by cardiologists in the cardiac catheterisation suite under general anaesthesia (95%) using a locking stylet (100%) with an Evolution RL (11-french 58.7%); a NES 13 millimetres curve (88%) was used to successfully snare 91% of the targeted leads. Complete procedural success was achieved in 92% of leads with 98.7% clinical success. Minor complications occurred in 2 cases (pneumothorax, pocket haematoma requiring intervention), in the absence of any major complications or peri-procedural mortality; there was no 30-day mortality.
Conclusion
The ‘Tandem’ procedure provides an additional strategy to improve the safety and efficacy of TLE, especially in leads of a long dwell time.
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Affiliation(s)
- Z Akhtar
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - Z Zuberi
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - LWM Leung
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - C Kontogiannis
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - K Waleed
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - AI Elbatran
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - M Sohal
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - MM Gallagher
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
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Leung L, Akhtar Z, Bajpai A, Li A, Sohal M, Norman M, Kaba R, Al-Subaie N, Louis-Auguste J, Hayat J, Zuberi Z, Gallagher M. Oesophageal protection during AF ablation: real world registry data and mechanisms behind the therapeutic effect of tissue cooling. Europace 2022. [DOI: 10.1093/europace/euac053.229] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Oesophageal protection using a dedicated device to provide controlled active thermal protection of the oesophagus during atrial fibrillation ablation has been shown to be effective at reducing endoscopically detected oesophageal lesions. Real world registry data of this device and established evidence on the effect of cooling on localized tissue after thermal injury have been under review.
Purpose
To determine the safety of an oesophageal temperature control device by a review of real-world registry data on its clinical use during catheter ablation procedures and to clarify basic mechanisms of its therapeutic action by a literature review of scientific studies on cooling in the context of thermal injury.
Methods
The United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE), FDA Medical and Radiation Emitting Device Recalls, the Medicines and Healthcare products Regulatory Agency (MHRA) Medical Device Alerts and SwissMedic records of Field Safety Corrective Actions (FSCA) databases were reviewed for any device-related adverse events. A systematic literature review was conducted to clarify the findings from studies investigating the physiological processes behind the therapeutic effect of cooling after tissue thermal injury.
Results
Of over 20,000 oesophageal temperature control devices clinically used, 7976 were recorded as having been used for the purpose of oesophageal protection during left atrial catheter ablations. No adverse events occurred related to its use during left atrial catheter ablations. No case of clinically significant oesophageal injury was reported in a patient who had been protected by the oesophageal temperature control device. 208 research articles retrieved from PubMed and MEDLINE that met the search criteria were reviewed. The common finding in all the studies was that cooling had an anti-inflammatory and restorative effect via modulation of several immune-mediated pathways, local cellular function and genetic expression.
Conclusions
There have been no adverse events reported to date in real world clinical use of an oesophageal temperature control device during left atrial catheter ablations, for the purpose of active thermal protection. Literature review data suggests that there are complex biophysical and cellular effects from cooling that leads to its therapeutic effect but further work is required to define the mechanisms of action of thermal protection in this specific context.
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Affiliation(s)
- L Leung
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - Z Akhtar
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - A Bajpai
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - A Li
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - M Sohal
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - M Norman
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - R Kaba
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - N Al-Subaie
- Ahmadi hospital, Anaesthetics, Kuwait, Kuwait
| | - J Louis-Auguste
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - J Hayat
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - Z Zuberi
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - M Gallagher
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
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Gallagher M, Akhtar Z, Gang Y, Gonna H, Li A, Bajpai A, Zuberi Z, Norman M, Sohal M, Leung LWM. Randomised comparison of achieve and traditional circular mapping catheters in cryoballoon ablation: results at up to a decade. Europace 2022. [DOI: 10.1093/europace/euac053.082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
A single-centre trial randomised patients to the use of the Achieve mapping catheter or a traditional circular mapping catheter during cryoballoon procedures for paroxysmal atrial fibrillation (AF) in 2011-2014. Long-term outcomes from the cohort were determined in 2021.
Purpose
To evaluate the determinants of long-term outcome of ablation for paroxysmal AF.
Methods
Patient and study procedure characteristics and clinical outcomes were determined, including mapping catheter assignment, model of cryoballoon used, AF recurrence, repeat ablations required, findings at repeat ablation long term survival of the patient.
Results
Of 102 patients in the original study, 98 had long-term (4.11+/-2.82 years) follow up data available. 35 patients (35.7%) had AF recurrence, giving a long-term success rate at 64.3% after 1 ablation, increasing to 81.6% after repeat ablation. Of the study cohort n=8 (8.16%) died at a median of 4.9 years after ablation (IQR:1.7-5.7). 25/98 (25.5%) patients had a second ablation and 7 (7.1%) had a third or more ablations. Those who had AF recurrence were older, with a higher prevalence of prior ischaemic heart disease and cardiac device implantation (p=0.02-0.03). After multi-variate analysis, a prior implanted cardiac device was the only significant predictor of recurrence (p=0.03).
Conclusion
Long-term outcomes after a 1st time PAF cryoablation were similar regardless of the type of mapping catheter used, the generation of cryoballoon, and traditional procedure endpoints. AF recurrences were more often detected in older patients with a history of ischaemic heart disease and implanted cardiac devices.
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Affiliation(s)
- M Gallagher
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - Z Akhtar
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - Y Gang
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - H Gonna
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - A Li
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - A Bajpai
- Epsom and St Helier University Hospitals NHS Trust, Cardiology, Epsom, United Kingdom of Great Britain & Northern Ireland
| | - Z Zuberi
- Royal Surrey County Hospital, Cardiology, Guildford, United Kingdom of Great Britain & Northern Ireland
| | - M Norman
- Frimley Park Hospital, Cardiology, Frimley, United Kingdom of Great Britain & Northern Ireland
| | - M Sohal
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - LWM Leung
- St George’s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
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6
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Akhtar Z, Gallagher MM, Leung LWM, Kontogiannis C, Elbatran AI, Zuberi Z, Sohal M. Tunnelled dialysis catheter extraction: a cardiology experience. Europace 2022. [DOI: 10.1093/europace/euac053.536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: None.
Background
Tunnelled dialysis catheters are integral to the management of patients with chronic kidney disease (CKD), providing a means to dialysis. They are prone to blockages necessitating removal. Most catheters are removed with manual traction without any sequalae by renal physicians whilst a small proportion require further intervention which may include interventional radiology or an ‘open’ surgical removal which carries additional risk. Cardiologists versed in transvenous lead extraction (TLE) provide an additional strategy.
Purpose
To evaluate the outcomes of tunnelled dialysis catheter ‘extractions’ performed by cardiologists at a high-volume TLE institute.
Method
All consecutive patients referred to cardiologists (1/10/2016 – 1/10/21) for extraction of tunnelled dialysis catheters following an unsuccessful attempt by the renal physicians and interventional radiology, were included in this series. Data of procedural outcomes was evaluated for safety and efficacy.
Results
Twelve patients (7 male) aged 64.15±15.04 years with a body mass index of 28.3 kg/m2 were referred for tunnelled catheter extraction for non-functioning lines (75%). Of these 12 CKD patients, the aetiology included focal segmental glomerulosclerosis (n=2), hypertension (n=2), diabetes (n=1) and sickle cell disease (n=1). In total, 12 tunnelled catheters (75%; n=9 right side) were completely removed (100%) using local anaesthesia (83.3%) in a procedure lasting 54.7±29.8 minutes and requiring 0.79±1.32 minutes of fluoroscopy. Eleven patients (91.7%) had their catheters successfully extracted with manual traction alone; 3 necessitated the use of a 0.035 stiff J-tip wire whilst one required the use of a rotational dissecting sheath Evolution (Cook Medical, USA). Of the 12 cases, 11 had a failed previous attempt including 1 patient who suffered a ventricular fibrillation cardiac arrest during the procedure and 1 was referred directly without an attempt as there was a concurrent pacemaker situated from the contralateral side; 4 patients had new lines placed and no significant complications occurred. There were no complications or procedural mortality.
Conclusion
Extraction of tunnelled dialysis catheter lines performed by cardiologists is safe and efficacious; experience in TLE is vital. This may provide an additional strategy for removal of these catheters when other percutaneous attempts fail.
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Affiliation(s)
- Z Akhtar
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - MM Gallagher
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - LWM Leung
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - C Kontogiannis
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - AI Elbatran
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - Z Zuberi
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
| | - M Sohal
- St George’s University Hospital NHS Foundation Trust, London, United Kingdom of Great Britain & Northern Ireland
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Long G, Tawbi H, Meyer N, Breznen B, Vyas C, Leung L, Moshyk A, Pushkarna D, Thakkar P, Fazeli M, Kotapati S, Schadendorf D. 1077P Treatment outcomes in patients (pts) with melanoma brain metastases (MBM) undergoing systemic therapy: A systematic literature review (SLR) and meta-analysis (MA) of real-world evidence (RWE). Ann Oncol 2021. [DOI: 10.1016/j.annonc.2021.08.1462] [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: 11/30/2022] Open
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Leung L, Bajpai A, Zuberi Z, Li A, Norman M, Kaba RA, Sohal M, Akhtar Z, Evranos B, Gonna H, Harding I, Al Subaie N, Louis-Auguste J, Hayat J, Gallagher MM. A registry review of 2532 catheter ablations for atrial fibrillation using active thermal protection. Europace 2021. [DOI: 10.1093/europace/euab116.250] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): Dr Leung has received research support from Attune Medical (Chicago, IL). Dr Gallagher has received research funding from Attune Medical (Chicago, IL).
Background
Thermal injury to the oesophagus causes a spectrum of adverse effects after ablation for atrial fibrillation (AF); at the most severe end, atrio-oesophageal fistula carries a high mortality rate. Controlled active thermal protection in the oesophagus during ablation is the most promising method of oesophageal protection. Randomized evidence from the IMPACT trial (NCT03819946) showed an 83.4% reduction in endoscopically detected oesophageal lesions compared to standard care when an oesophageal temperature control device was used to control the local temperature. The IMPACT patients who were randomized to the use of the device had no adverse event related to its use. Real world registry data on applications of this device have not previously been available.
Purpose
To determine the safety of an oesophageal temperature control device by review of real-world registry data on its clinical use and any reported device-related adverse events.
Methods
We reviewed the following databases for any reported oesophageal temperature control device-related complications: The United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE), FDA Medical and Radiation Emitting Device Recalls, the Medicines and Healthcare products Regulatory Agency (MHRA) Medical Device Alerts and SwissMedic records of Field Safety Corrective Actions (FSCA). An internal registry (post-marketing follow up) database maintained by the manufacturer of the device was used to quantify the number used for each indication. Reported events were reviewed and catalogued for description and identification of any events related to its use in the cardiac electrophysiology lab. The IMPACT study patients were reviewed for any device-related events.
Results
Of the 13, 284 oesophageal temperature control devices used, 2532 were recorded as having been used for the purpose of oesophageal protection during catheter ablation for AF. A total of 5 events associated with the device were identified, all from the MAUDE database. Three were from 2017, one from 2018, and one from 2019. All involved its use in critical care or trauma patients and were related to user error or contraindicated patient selection; none resulted in serious harm to the patient. No adverse events occurred related to its use in the cardiac electrophysiology lab. No case of clinically significant oesophageal injury was reported in a patient who had been protected by the oesophageal temperature control device.
Conclusions
Real world registry data has shown no adverse events reported to date in over 2500 uses of an oesophageal temperature control device in the cardiac electrophysiology lab, for the purpose of active thermal protection. This data supports the randomized trial evidence of its clinical effectiveness. Abstract Figure. Oesophageal active thermal protection
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Affiliation(s)
- L Leung
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - A Bajpai
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - Z Zuberi
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - A Li
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - M Norman
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - RA Kaba
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - M Sohal
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - Z Akhtar
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - B Evranos
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - H Gonna
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - I Harding
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - N Al Subaie
- Ahmadi hospital, Anaesthetics , Kuwait, Kuwait
| | - J Louis-Auguste
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - J Hayat
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - MM Gallagher
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
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Leung L, Imhoff RJ, Frame D, Mallow PJ, Goldstein L, Taylor H, Gallagher MM. Cost-effectiveness of catheter ablation versus medical therapy for the treatment of atrial fibrillation in the United Kingdom. Europace 2021. [DOI: 10.1093/europace/euab116.531] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Private company. Main funding source(s): This research study was funded by Biosense Webster, Inc. Dr Leung has received research support from Attune Medical (Chicago, IL) towards a research fellowship at St. George"s University of London. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
Background
Randomised data on patient-related outcomes comparing catheter ablation to medical therapy for the treatment of atrial fibrillation (AF) have shown the effectiveness of catheter ablation. Ablation versus medical therapy should also be analysed from a health economics perspective to achieve optimal healthcare resource allocation.
Purpose
To determine the cost effectiveness of catheter ablation compared to medical therapy for the treatment of atrial fibrillation, from the perspective of the UK National Health Service.
Methods
A patient-level Markov health-state transition model was used to conduct a cost utility analysis comparing catheter ablation and medical therapy for the treatment of AF. A systematic review and meta-analysis of catheter ablation treatment versus medical therapy (rhythm and/or rate control drugs) was conducted to enable comparison of AF recurrence between treatment groups utilising the model. Additional model parameters were established based upon a best-evidence review of the literature. The model simulated care delivered from a secondary care perspective. Total patients simulated in this model over a lifetime were 250,000, with patients entering the model at age 64. Only previously treated AF patients were included, including those with concomitant heart failure. A separate scenario analysis was conducted to determine the cost effectiveness specifically in the cohort of patients with AF and heart failure.
Main outcomes measures
Incremental cost-effectiveness ratio (ICER) and average total expected costs and quality-of-life years (QALYs) incurred over the lifetime of a patient. AF recurrence, complications and cardiovascular adverse events were compared over the total duration inside the model.
Results
In the base case analysis, catheter ablation resulted in a favourable ICER of £8,614 per additional QALY gained when compared to medical therapy, well below the national Willingness-to-Pay threshold of £20,000. Catheter ablation was associated with an expected increase of 1.01 QALYs, while adding an additional cost £8,742 over a patient’s lifetime. The cost-effectiveness of catheter ablation was improved in the heart failure sub-group analysis, with an ICER of £6,438. A significantly greater proportion of patients in the medical therapy group failed rhythm control at any stage compared to catheter ablation (72% vs 24%) and at a faster rate (median time to treatment failure: 3.8 vs 10 years).
Conclusion
Catheter ablation appears to be a highly cost-effective treatment for atrial fibrillation, compared to medical therapy, from the perspective of the UK National Health Service. With low rates of adverse events and superiority in achieving rhythm control, AF ablation services should be prioritised with appropriate allocation of healthcare resources.
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Affiliation(s)
- L Leung
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
| | - RJ Imhoff
- CTI Clinical Trial and Consulting , Real-World Evidence and Late Phase Research, Kentucky, United States of America
| | - D Frame
- CTI Clinical Trial and Consulting , Real-World Evidence and Late Phase Research, Kentucky, United States of America
| | - PJ Mallow
- Xavier University , Health Services Administration , Ohio, United States of America
| | - L Goldstein
- Biosense Webster , Irvine, United States of America
| | - H Taylor
- Johnson & Johnson Medical Limited, Berkshire, United Kingdom of Great Britain & Northern Ireland
| | - MM Gallagher
- St George"s Hospital (London), London, United Kingdom of Great Britain & Northern Ireland
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10
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Leung L, Bajpai A, Zuberi Z, Li A, Norman M, Kaba R, Akhtar Z, Evranos B, Gonna H, Harding I, Sohal M, Al-Subaie N, Louis-Auguste J, Hayat J, Gallagher M. Patient outcomes after AF ablation using Ablation Index technology with oesophageal protection: insight from the IMPACT study. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.0619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Atrio-oesophageal fistula formation accounts for the majority of AF ablation-related morbidity and mortality. Thermal injury to the oesophagus can be significantly reduced by application of oesophageal cooling for protection during AF ablation. The effect of this method of oesophageal protection in patients receiving radiofrequency (RF) ablation guided by Ablation Index technology is currently unknown.
Objective
To investigate the ability of a temperature control device to protect the oesophagus from ablation-related thermal injury in patients receiving AF ablation guided by Ablation Index technology.
Methods
The IMPACT study is a single-centre, prospective, double-blind randomized controlled trial, which investigated the ability of a controlled method of oesophageal cooling to protect the oesophagus from ablation-related thermal injury. The EnsoETM device was used to deliver oesophageal cooling. This method was compared in a 1:1 randomization to a control group of standard practice utilizing a single-sensor temperature probe. In the study group, the device was used to keep the luminal temperature at 4°C during RF ablation. All participants received AF ablation using Ablation Index technology at posterior and anterior settings (30W at 350–400 and 40W at 450–500, respectively). Endoscopic examination was performed within 7 days post-ablation and oesophageal injury was graded. The patient and the endoscopist were blinded to the randomization. Structured clinical follow up occurred after 3 months post-ablation; both patient and follow up clinician were blinded.
Results
We recruited 188 patients, of whom 120 underwent endoscopic evaluation. Thermal injury to the mucosa was significantly more common in the control group than in those receiving oesophageal protection (12/60 versus 2/60; P=0.008). There was no difference between groups in RF time, lesion duration, force, power and combined ablation index (P value range= 0.2–0.9). Procedure and fluoroscopy duration were similar (P=0.97, P=0.91 respectively). The majority of those who passed through the 1st follow up evaluation (n=136) did not have gastrointestinal or chest pain symptoms post ablation and there was no difference between the randomized groups. Only 4.4% overall had severe symptoms and they were poorly correlated against those who sustained mucosal lesions. AF recurrence was similar in both groups (8% vs 8.8%). There were 2 cases of vascular trauma needing intervention in the control group and 1 case of conservatively managed pericardial effusion in the protected group only. Clinical and endoscopy findings did not report any EnsoETM device-related trauma.
Conclusion
Thermal protection of the oesophagus significantly reduces ablation-related thermal injury compared to standard care when ablation is performed using radiofrequency with Ablation Index technology. This method of oesophageal protection is safe and does not compromise the efficacy of the ablation procedure.
Endoscopy findings and patient symptoms.
Funding Acknowledgement
Type of funding source: Public hospital(s). Main funding source(s): 1. Public hospital: St. George's NHS Foundation Trust; 2. Private company: Attune Medical (Chicago, IL)
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Affiliation(s)
- L Leung
- St. George's Hospital, London, United Kingdom
| | - A Bajpai
- St. George's Hospital, London, United Kingdom
| | - Z Zuberi
- St. George's Hospital, London, United Kingdom
| | - A Li
- St. George's Hospital, London, United Kingdom
| | - M Norman
- St. George's Hospital, London, United Kingdom
| | - R Kaba
- St. George's Hospital, London, United Kingdom
| | - Z Akhtar
- St. George's Hospital, London, United Kingdom
| | - B Evranos
- St. George's Hospital, London, United Kingdom
| | - H Gonna
- St. George's Hospital, London, United Kingdom
| | - I Harding
- St. George's Hospital, London, United Kingdom
| | - M Sohal
- St. George's Hospital, London, United Kingdom
| | - N Al-Subaie
- St. George's Hospital, London, United Kingdom
| | | | - J Hayat
- St. George's Hospital, London, United Kingdom
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11
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Yeh E, Wong E, Strohl K, Gu W, Tsai C, Leung L, Yar W, Chiang A. 1202 Validation Of A Novel Wearable Home Sleep Testing Device For Assessment Of Obstructive Sleep Apnea. Sleep 2020. [DOI: 10.1093/sleep/zsaa056.1196] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
There is a substantial need for an accurate and easy-to-use tool for obstructive sleep apnea (OSA) assessment. Belun Ring Platform (BRP), a novel photoplethysmography (PPG)-based home sleep apnea testing system with a proprietary deep learning algorithm, has been shown to have good sensitivity and specificity in predicting OSA in subjects without significant comorbidities and medications known to affect heart rate (HR). In this study, we further tested its performance in subjects referred for in-lab polysomnography (PSG) assessment of sleep disorders without excluding those with non-arrhythmia comorbidities or the subjects on HR-affecting medications.
Methods
PSG was recorded simultaneously with the Ring in the sleep lab and the studies were manually scored by certified sleep technicians according to the AASM Scoring manual version 2.4. Exclusion criteria include age <18, unstable cardiopulmonary status, recent hospitalization within 30 days, significant arrhythmias, baseline HR <50 or >100, home oxygen use, pacemaker/defibrillator, post-cardiac transplantation or Left ventricular assist device.
Results
A cohort of 78 individuals (26 males and 52 females, age 50.5) were studied with 26 taking HR-affecting medications. Of these, 35 (45%) had AHI < 5; 14 (18%) had AHI 5-15; 15 (19%) had AHI 15-30; 14 (18%) had AHI > 30. The Ring-REI correlated well with the PSG-AHI (r =0.83, P <0.001). The accuracy, sensitivity, specificity in categorizing AHI >15 were 0.808, 0.931, and 0.735 respectively. The positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio were 0.675, 0.947, 3.509, and 0.094 respectively. The use of HR-affecting medications did not significantly affect the sensitivity and specificity of BRP in predicting OSA (P =0.16 and 0.44 respectively).
Conclusion
BRP is promising as a reasonable tool for OSA assessment and can potentially be incorporated into a broad spectrum of clinical practices for identification of patients with OSA.
Support
This study is supported by a Grant from Belun Technology Company Limited.
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Affiliation(s)
- E Yeh
- University Hospitals, CLEVELAND, OH
| | - E Wong
- University Hospitals, CLEVELAND, OH
| | - K Strohl
- University Hospitals, CLEVELAND, OH
| | - W Gu
- Belun Technology Company Limited, Hong Kong, HONG KONG
| | - C Tsai
- Belun Technology Company Limited, Hong Kong, HONG KONG
| | - L Leung
- Belun Technology Company Limited, Hong Kong, HONG KONG
| | - W Yar
- University Hospitals, CLEVELAND, OH
| | - A Chiang
- University Hospitals, CLEVELAND, OH
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12
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Leung L, Hung K, Lo R, Yeung C, Chan S, Graham C. 6 Prognostic Value of qSOFA, SIRS and News in the Emergency Department for Predicting 7-Day Mortality: A Prospective Study. Ann Emerg Med 2018. [DOI: 10.1016/j.annemergmed.2018.08.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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13
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Leung L, Wang E, Lee B. ADVERSE EFFECTS OF HIGH-DOSE VS STANDARD-DOSE DEXMEDETOMIDINE IN THE CARDIAC SURGERY POPULATION: A RETROSPECTIVE COHORT REVIEW. Can J Cardiol 2018. [DOI: 10.1016/j.cjca.2018.07.319] [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: 10/28/2022] Open
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14
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Leung L, Evranos B, Gonna H, Gomes J, Harding I, Raju H, Angelozzi A, Domenichini G, Zuberi Z, Norman M, Gallagher M. 220Simultaneous multi-catheter cryotherapy for the treatment of accessory pathways refractory to radiofrequency catheter ablation. Europace 2018. [DOI: 10.1093/europace/euy015.069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- L Leung
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
| | - B Evranos
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
| | - H Gonna
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
| | - J Gomes
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
| | - I Harding
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
| | - H Raju
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
| | - A Angelozzi
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
| | - G Domenichini
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
| | - Z Zuberi
- Royal Surrey County Hospital, Cardiology Department, Guildford, United Kingdom
| | - M Norman
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
| | - M Gallagher
- St George's University of London, Cardiology Clinical Academic Group, London, United Kingdom
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Ma B, King AD, Leung L, Wang K, Poon A, Ho WM, Mo F, Chan CML, Chan ATC, Wong SCC. Identifying an early indicator of drug efficacy in patients with metastatic colorectal cancer-a prospective evaluation of circulating tumor cells, 18F-fluorodeoxyglucose positron-emission tomography and the RECIST criteria. Ann Oncol 2018; 28:1576-1581. [PMID: 28379285 DOI: 10.1093/annonc/mdx149] [Citation(s) in RCA: 14] [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: 08/16/2016] [Indexed: 12/20/2022] Open
Abstract
Background This study investigated the predictive and prognostic significance of assessing early drug response with both positron-emission computerized tomography (PET-CT) and circulating tumor cells (CTCs) in patients receiving first-line chemotherapy for metastatic colorectal cancer. Patients and methods Eligible patients had PET-CT and CTC analysis at baseline and 4-6 weeks after starting chemotherapy, and then a CT scan at 10-12 weeks to assess the Response Evaluation Criteria In Solid Tumors (RECIST) response. Early response was defined as achieving a dual-endpoint consisting of PET-CT (30% drop in the sum of maximum standard uptake values-SUVmax-of target lesions) and CTC response (CTC < 3 cells/7.5 ml blood) at 4-6 weeks after starting chemotherapy. Results About 84 patients were enrolled with a median follow-up of 32.9 months (95% confidence interval, CI, 24.5 months-not reached, NR), and 70 patients (84.3%) completed all assessments. Achieving an early response based on the dual-endpoint was independently associated with progression-free survival (hazard ratio, HR = 0.452, 95% CI 0.267-0.765). The median progression-free survival of early responders was 7.41 months (95% CI, 6.05-9.11) compared with 5.37 months (95% CI, 4.68-6.24) in non-responders (log-rank, P = 0.0167). RECIST response at 10 weeks was independently associated with overall survival (OS) (HR = 0.484, 95% CI, 0.275-0.852). Early response based on the dual-endpoint could predict the subsequent RECIST response with a sensitivity, specificity and positive predictive value of 64%, 70% and 74%, respectively. Conclusions Early response based on both PET-CT and CTC analysis has prognostic and probably predictive significance in patients undergoing first-line chemotherapy for metastatic colorectal cancer. Its utility as a new tool for assessing early drug response should be further validated.
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Affiliation(s)
- B Ma
- State Key Laboratory of Oncology in South China, Department of Clinical Oncology, Sir Y K Pao Centre for Cancer, Hong Kong Cancer Institute
| | - A D King
- Department of Diagnostic and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR
| | - L Leung
- State Key Laboratory of Oncology in South China, Department of Clinical Oncology, Sir Y K Pao Centre for Cancer, Hong Kong Cancer Institute
| | - K Wang
- Department of Diagnostic and Interventional Radiology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong SAR
| | - A Poon
- State Key Laboratory of Oncology in South China, Department of Clinical Oncology, Sir Y K Pao Centre for Cancer, Hong Kong Cancer Institute
| | - W M Ho
- State Key Laboratory of Oncology in South China, Department of Clinical Oncology, Sir Y K Pao Centre for Cancer, Hong Kong Cancer Institute
| | - F Mo
- State Key Laboratory of Oncology in South China, Department of Clinical Oncology, Sir Y K Pao Centre for Cancer, Hong Kong Cancer Institute
| | - C M L Chan
- State Key Laboratory of Oncology in South China, Department of Clinical Oncology, Sir Y K Pao Centre for Cancer, Hong Kong Cancer Institute
| | - A T C Chan
- State Key Laboratory of Oncology in South China, Department of Clinical Oncology, Sir Y K Pao Centre for Cancer, Hong Kong Cancer Institute
| | - S C C Wong
- Department of Health Technology and Informatics, Faculty of Health and Social Sciences, Hong Kong Polytechnic University, Hong Kong SAR, China
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Loong H, Huang M, Wong C, Leung L, Burke T, Chandwani S, Law A, Tan S. P1.01-050 Cost-Effectiveness of PDL1 Based Test-And-Treat Strategy with Pembrolizumab as the 1st Line Treatment for NSCLC in Hong Kong. J Thorac Oncol 2017. [DOI: 10.1016/j.jtho.2017.09.704] [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: 10/18/2022]
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17
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Leung L, Li A, Saba M. P1709Circadian rhythm variability of right and left ventricular outflow tract ectopy. Eur Heart J 2017. [DOI: 10.1093/eurheartj/ehx502.p1709] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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18
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Leung L, Gonzalez-Matos C, Bajpai A, Saba M. P1037Post-ablation mahaim accessory pathway automaticity: a rare cause of recurrent symptoms. Europace 2017. [DOI: 10.1093/ehjci/eux151.217] [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: 11/14/2022] Open
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19
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Lam P, Cheng S, Lo W, Tong C, Lo K, Lam Y, Leung L, Leung P. Topical application of mesenchymal stem cells for the treatment of chronic wounds- a pilot study. Cytotherapy 2017. [DOI: 10.1016/j.jcyt.2017.02.320] [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: 11/16/2022]
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20
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Pacis MM, Leung L, Harkins GJ. Fundamentals of Pelvic Anatomy in Laparoscopic Surgery. J Minim Invasive Gynecol 2016. [DOI: 10.1016/j.jmig.2016.08.438] [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: 10/20/2022]
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21
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Fuller NR, Fong M, Gerofi J, Leung L, Leung C, Denyer G, Caterson ID. A randomized controlled trial to determine the efficacy of a high carbohydrate and high protein ready-to-eat food product for weight loss. Clin Obes 2016; 6:108-16. [PMID: 26781700 DOI: 10.1111/cob.12137] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 11/04/2015] [Accepted: 12/07/2015] [Indexed: 11/30/2022]
Abstract
UNLABELLED Incorporating meal replacements has been shown to produce a significantly greater weight loss than a conventional reduced calorie diet. Ready-to-eat conventional foods may also be effective in this role and provide additional benefit because of their palatability, acceptance and enjoyment and thus increase dietary compliance. This trial investigated the efficacy of a ready-to-eat food product (Vita-Weat biscuit) that is both high in carbohydrate and high in protein as part of a diet prescription for weight loss in an overweight and obese population group. A total of 76 participants were randomized to a 6-week weight loss intervention including the ready-to-eat food product (intervention group) or advice on the 'Australian Guide to Healthy Eating' (control group). Both groups lost approximately 2 kg weight which equated to a reduction in body mass index of 0.70 kg m(-2) . There was no significant difference in percentage weight loss from screening to 6 weeks between the two groups; mean difference for the intervention vs. CONTROL GROUP -0.20% (95% confidence interval: -0.96, 1.36); P = 0.73. Both diets were nutritionally matched and well-accepted over the 6-week period. This study shows that the inclusion of a ready-to-eat food product can be included as part of a dietary programme to achieve a clinically significant weight loss over a short period. This may have benefit when incorporated into an individual's meal plan intermittently to assist weight control. It also provides support for current public health nutritional guidelines as the participants in this study following such advice were also successful in achieving a clinically meaningful weight loss.
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Affiliation(s)
- N R Fuller
- The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - M Fong
- The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - J Gerofi
- The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - L Leung
- The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - C Leung
- The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - G Denyer
- The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, The University of Sydney, Sydney, Australia
| | - I D Caterson
- The Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, Charles Perkins Centre, The University of Sydney, Sydney, Australia
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22
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Chen CHK, Leung L, Boldyrev S, Maruca BA, Bale SD. Ion-scale spectral break of solar wind turbulence at high and low beta. Geophys Res Lett 2014; 41:8081-8088. [PMID: 26074642 PMCID: PMC4459186 DOI: 10.1002/2014gl062009] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2014] [Accepted: 10/14/2014] [Indexed: 05/29/2023]
Abstract
The power spectrum of magnetic fluctuations in the solar wind at 1 AU displays a break between two power laws in the range of spacecraft-frame frequencies 0.1 to 1 Hz. These frequencies correspond to spatial scales in the plasma frame near the proton gyroradius ρi and proton inertial length di. At 1 AU it is difficult to determine which of these is associated with the break, since [Formula: see text] and the perpendicular ion plasma beta is typically β⊥i∼1. To address this, several exceptional intervals with β⊥i≪1 and β⊥i≫1 were investigated, during which these scales were well separated. It was found that for β⊥i≪1 the break occurs at di and for β⊥i≫1 at ρi, i.e., the larger of the two scales. Possible explanations for these results are discussed, including Alfvén wave dispersion, damping, and current sheets.
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Affiliation(s)
- C H K Chen
- Department of Physics, Imperial College London London, UK ; Space Sciences Laboratory, University of California Berkeley, California, USA
| | - L Leung
- Space Sciences Laboratory, University of California Berkeley, California, USA
| | - S Boldyrev
- Department of Physics, University of Wisconsin-Madison Madison, Wisconsin, USA
| | - B A Maruca
- Space Sciences Laboratory, University of California Berkeley, California, USA
| | - S D Bale
- Space Sciences Laboratory, University of California Berkeley, California, USA ; Department of Physics, University of California Berkeley, California, USA
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23
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Liang S, Leung L, Putta S, Hotson D, Rosen D, Hawtin R. 109 Functional activity, but not PD-1 expression level, differentiates primary CLL from healthy PD1+ T cells using SCNP. Eur J Cancer 2014. [DOI: 10.1016/s0959-8049(14)70235-7] [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: 10/24/2022]
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24
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Leung SF, Chan KCA, Ma BB, Hui EP, Mo F, Chow KCK, Leung L, Chu KW, Zee B, Lo YMD, Chan ATC. Plasma Epstein-Barr viral DNA load at midpoint of radiotherapy course predicts outcome in advanced-stage nasopharyngeal carcinoma. Ann Oncol 2014; 25:1204-8. [PMID: 24638904 DOI: 10.1093/annonc/mdu117] [Citation(s) in RCA: 148] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND To test the hypothesis that prognostication of treatment outcome is feasible by biomarker response at midcourse of chemoradiotherapy (CRT)/radiotherapy (RT), with respect to the plasma load of Epstein-Barr viral (EBV) DNA in nasopharyngeal carcinoma (NPC). PATIENTS AND METHODS One hundred seven patients with stage IIB-IV NPC were prospectively studied. Plasma EBV DNA load was measured by quantitative PCR before therapy (pre-DNA), at completion of 4 weeks of CRT/RT (mid-DNA), and within 3 months of completion of therapy (post-DNA). The end points are post-DNA load, a recognized surrogate of survival, and clinical outcome. RESULTS Ninety-three percent of patients had detectable EBV DNA before therapy (median load = 972 copies/ml). EBV DNA became undetectable in 55 (51%) patients at the end of week 4 of therapy. Detectable mid-DNA was associated with worse clinical outcome (median follow-up time, 6.2 years), for distant failure [hazard ratio (HR) 12.02, 95% confidence interval (CI) 2.78-51.93; P < 0.0001], progression-free survival (PFS; HR 4.05, 95% CI 1.89-8.67, P < 0.0001), and overall survival (OS; HR 3.29, 95% CI 1.37-7.90, P = 0.0077). Seventy-four percent of all failures were associated with detectable mid-DNA, whereas 34% of all failures were associated with detectable post-DNA. Stratification by tumor stage (IIB, III, IV) has no significant prognostic effect. CONCLUSIONS Unfavorable EBV DNA response at midcourse of RT/CRT is an adverse prognosticator for treatment outcome, is linked to majority of all failures, and discriminates outcome better than tumor stage. The data could provide a basis for trial design that addresses alteration of therapy intensity during the latter phase of CRT, and adjuvant therapy. Validation studies are awaited.
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Affiliation(s)
| | | | - B B Ma
- Department of Clinical Oncology
| | - E P Hui
- Department of Clinical Oncology
| | - F Mo
- Department of Clinical Oncology
| | | | - L Leung
- Department of Clinical Oncology
| | - K W Chu
- Department of Clinical Oncology
| | - B Zee
- Department of School of Public Health, State Key Laboratory in Oncology in South China, Sir YK Pao Center for Cancer, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Y M D Lo
- Department of Chemical Pathology
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Saha P, Aksan N, Andersen J, Yan J, Simoneau J, Leung L, Bertrand F, Aoto K, Kamide H. Issues and future direction of thermal-hydraulics research and development in nuclear power reactors. Nuclear Engineering and Design 2013. [DOI: 10.1016/j.nucengdes.2012.07.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
OBJECTIVE To investigate the impact of subinguinal microsurgical varicocelectomy on semen parameters and pregnancy outcomes in couples with male factor subfertility. DESIGN Case series. SETTING Male Infertility Clinic in an academic institution in Hong Kong. PATIENTS The clinical records of 42 consecutive subfertile male patients who had subinguinal microsurgical varicocelectomy (from January 2000 to December 2009) were retrospectively reviewed. All the patients had a known history of subfertility and abnormalities in one or more semen parameters. Female subfertility factors were not addressed. Only grade 2 or higher clinically palpable varicoceles were operated on. MAIN OUTCOME MEASURES Preoperative and postoperative semen analyses based on the World Health Organization criteria; the outcome measures included changes in semen parameters and whether a pregnancy ensued. RESULTS The mean age of patients and their spouses were 38 and 33 years, respectively. The mean duration of infertility was 4 years; 37 patients had primary infertility and five had secondary infertility. The mean (± standard deviation) sperm concentration improved from 12 ± 19 million/mL to 23 ± 29 million/mL following varicocelectomy (P<0.001), the mean sperm motility improved from 26% ± 16% to 32% ± 18% (P<0.001), and the mean normal morphology increased from 5% ± 7% to 6% ± 6% (P<0.001). Postoperatively, 23 (55%) of the patients achieved pregnancy, 11 (26%) being spontaneous, 1 (2%) by intrauterine insemination, and 11 (26%) by in-vitro fertilisation. Among 20 patients with severe preoperative oligospermia (<5 million/mL), statistically significant improvements occurred in postoperative mean sperm concentration, motility and morphology (all P<0.001), and five (25%) of them achieved a spontaneous pregnancy. There was one intra-operative injury to the testicular artery with immediate repair and no testicular atrophy. Five (12%) of the patients had recurrences. No preoperative factors appeared predictive of a pregnancy ensuing. CONCLUSIONS In couples with male infertility due to varicoceles, subinguinal microsurgical varicocelectomy was shown to improve sperm concentrations, motility and morphology, and the likelihood of a pregnancy. Spontaneous pregnancy was achieved in 25% of the couples in which the man had severe oligospermia.
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Affiliation(s)
- L Leung
- Department of Surgery, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong
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Lau CT, Leung L, Chan IHY, Chung PHY, Lan LCL, Chan KL, Wong KKY, Tam PKH. Thoracoscopic resection of congenital cystic lung lesions is associated with better post-operative outcomes. Pediatr Surg Int 2013; 29:341-5. [PMID: 23292534 DOI: 10.1007/s00383-012-3243-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
INTRODUCTION The incidence of congenital cystic lung lesions has been increasing in recent years due to better antenatal detection. With the introduction and maturation of thoracoscopy, the operative management for these lesions has seen advancement in the last decade. In this study, we aimed to compare the post-operative outcomes of patients who had thoracoscopic resection with those who underwent open resection. METHODS A retrospective review of all patients who underwent surgery for congenital cystic lung lesions between January 1996 and June 2012 in a tertiary referral center was conducted. Patients' demographics, operative procedures and post-operative outcomes were analyzed. RESULTS Sixty-seven patients were identified over the past 15 years. Thirty-nine patients had thoracoscopic resections and 28 had open resections. Thirteen patients in the thoracoscopic group required conversion. Both groups had similar demographics in terms of age, body weight and laterality of lesions. The mean operative time and blood loss in the two groups were comparable. Patients in the thoracoscopic group had significantly shorter duration of chest tube drainage (4.3 vs. 6.9 days, p = 0.004), shorter intensive care unit stay (2.5 vs. 5.9 days, p = 0.003) and shorter hospital stay (6.9 vs. 12.0 days, p < 0.001). Post-operative complication rate was similar between the two groups. Patients with body weight less than 5 kg showed a significantly higher conversion to open surgery as compared to those with body weight more than 5 kg (62.5 vs. 25.8 %, p = 0.049). CONCLUSION Successful thoracoscopic resection for congenital cystic lung lesions results in better post-operative outcomes. However, this technique remains technically challenging in patients with body weight less than 5 kg.
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Affiliation(s)
- C T Lau
- Department of Surgery, The University of Hong Kong, Queen Mary Hospital, Pokfulam Road, Hong Kong SAR, China
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Leung L. An investigation of the association between diet and occurrence of acne: a rational approach from a traditional Chinese medicine perspective - comment. Clin Exp Dermatol 2012; 37:73-4. [DOI: 10.1111/j.1365-2230.2011.04112.x] [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: 11/29/2022]
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Eisenstein A, Leung L, Lim T, Ning Z, Polanyi JC. Reaction dynamics at a metal surface; halogenation of Cu(110). Faraday Discuss 2012; 157:337-53; discussion 375-98. [DOI: 10.1039/c2fd20023f] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Chan SL, Chan AK, Hui EP, Yu S, Leung L, Loong HHF, Ma B, Mok T, Chan ATC, Yeo W. Quantitation of circulating methylated RASSF1A in prognostication and monitoring of treatment response in unresectable hepatocellular carcinoma (HCC). J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.4058] [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: 11/20/2022] Open
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Starr C, Nekaris KAI, Streicher U, Leung L. Traditional use of slow lorises Nycticebus bengalensis and N. pygmaeus in Cambodia: an impediment to their conservation. ENDANGER SPECIES RES 2010. [DOI: 10.3354/esr00285] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Al-Badriyeh D, Leung L, Davies GE, Stewart K, Kong D. Successful Use of Topical Voriconazole 1% Alone as First-Line Antifungal Therapy Against Candida albicans Keratitis. Ann Pharmacother 2009; 43:2103-7. [DOI: 10.1345/aph.1m318] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Leung L, Manini A, Wilson D. 365: Fatal Toxicity From Nucleoside Reverse Transcriptase Inhibitor Use: Factors Implicated With Symptomatic Hyperlactemia Emergencies. Ann Emerg Med 2009. [DOI: 10.1016/j.annemergmed.2009.06.397] [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: 10/20/2022]
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Tegay DH, Chan KK, Leung L, Wang C, Burkett S, Stone G, Stanyon R, Toriello HV, Hatchwell E. Toriello-Carey syndrome in a patient with ade novobalanced translocation [46,XY,t(2;14)(q33;q22)] interrupting SATB2. Clin Genet 2009; 75:259-64. [DOI: 10.1111/j.1399-0004.2008.01145.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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Abstract
In this study, bioscaffolds using poly(DL-lactide-co-glycolide) acid (PLGA) were fabricated and studied. The gas foaming/salt leaching technique in a batch foaming setup was employed, and the effects of material composition of PLGA on the morphology and mechanical properties using this process were investigated. Two material compositions of PLGA 50/50 and 85/15 were used, and characterization of scaffolds fabricated with these materials showed that a lower relative density can be achieved with an increasing poly(DL-lactide) acid (PDLLA) content; however, higher open-cell porosity was obtained with lower PDLLA content. Furthermore, the effect of PLGA composition on modulus of the scaffolds was minor.
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Affiliation(s)
- L Leung
- Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, Ontario, M5S 3G8, Canada
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36
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Mok T, Lui P, Lam KC, Yim A, Wan I, Lee S, Hsin M, Leung L, To K. Novel mutations and mutation pattern of epidermal growth factor receptor (EGFR) gene in Chinese patients with primary lung adenocarcinoma. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.7667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
7667 Background: EGFR mutation is a diverse and complex phenomenon. Shigematsu et al (JNCI 97:339,2005), analyzing NSCLC samples from multiple ethnicities and histologic cell types, reported 11 types of in-frame deletions in exon 19 (46%), 9 missense mutation in exons 18, 20, 21 (45%) and 8 in-frame insertion in exons 20 (9%). 3/130 tumors (2.3%) had multiple mutations. Here we report the incidence, mutation pattern and novel finding of EGFR mutation in a homogenous ethnic group with adenocarcinoma of lung. Methods: Between 2004 and 2006 we isolated genomic DNA from 194 (archival 53, prospective 141) primary lung adenocarinoma for PCR amplification of EGFR exon 18–21. We isolated tumor cell by micro-dissection. PCR products were purified and sequenced using the BigDye Terminator Cycly Sequencing Ready Reaction Kit (Applied Biosystem) and run on Applied Biosystem 3100 Genetic Analyzer. Results: We found 79 EGFR mutations in 73 tumors (37.6%). Six (8.2%) had double mutations. IN-FRAME DEL: 10 types in exon 19 (39 cases, 49.4%); 1 type in exon 18 (1 case). MISSENSE MUTATION: 2 types in exon 18 (2 cases); 4 types in exon 20 (5 cases) and 2 types in exon 21 (29 cases, 36.7%) IN-FRAME INSERTION: 3 types in exon 20 (3 cases). Typical exon 19 E746-A750del and exon 21 L858R mutations accounted for 31% and 34%, respectively. We found 11 types of mutations not previously described.( Table ) Four pts with novel mutations received EGFR TKI and 3 attained PR (all with exon 19 del). Two pts have T790M mutations without prior exposure to EGFR TKI and both with double mutations. Conclusion: Mutation pattern of EGFR gene in Chinese pts with adenocarcinoma is similar to the Shigematsu report. The overall incidence of EGFR mutation and multiple mutations are higher but in-frame insertion in exon 20 is less common. Majority of the novel mutations are rare mutations involving exon 18 and 20. No significant financial relationships to disclose. [Table: see text]
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Affiliation(s)
- T. Mok
- The Chinese Univ of Hong Kong, Shatin, Hong Kong
| | - P. Lui
- The Chinese Univ of Hong Kong, Shatin, Hong Kong
| | - K. C. Lam
- The Chinese Univ of Hong Kong, Shatin, Hong Kong
| | - A. Yim
- The Chinese Univ of Hong Kong, Shatin, Hong Kong
| | - I. Wan
- The Chinese Univ of Hong Kong, Shatin, Hong Kong
| | - S. Lee
- The Chinese Univ of Hong Kong, Shatin, Hong Kong
| | - M. Hsin
- The Chinese Univ of Hong Kong, Shatin, Hong Kong
| | - L. Leung
- The Chinese Univ of Hong Kong, Shatin, Hong Kong
| | - K. To
- The Chinese Univ of Hong Kong, Shatin, Hong Kong
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Shilling AD, Azam F, Kao J, Leung L. Use of canalicular membrane vesicles (CMVs) from rats, dogs, monkeys and humans to assess drug transport across the canalicular membrane. J Pharmacol Toxicol Methods 2006; 53:186-97. [PMID: 16176877 DOI: 10.1016/j.vascn.2005.08.003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2004] [Accepted: 08/09/2005] [Indexed: 11/15/2022]
Abstract
INTRODUCTION A novel application of a Ultrafree filter cartridge/centrifugation method was evaluated to determine uptake in canalicular membrane vesicles (CMVs) from SD rats, beagle dogs, cynomolgus monkeys (common safety species in the pharmaceutical industry) and humans to assess biliary transport. METHODS CMVs prepared from fresh livers of rats, dogs, monkeys and humans (four donors) were characterized for enrichment, basolateral and Golgi contamination and orientation. The presence of MRP2 and p-glycoprotein (P-gp) were confirmed by Western blots. Uptake of [3H]-leukotriene C4 (LTC4) and [3H]-estradiol-17beta-d-glucuronide (E2-Gluc) was determined at a low substrate concentration and/or by kinetic measurements (K(m) and V(max)). Correlation of in vitro data with in vivo findings was achieved by determining the biliary clearance of E2-Gluc in rats after a single i.v. dose and with literature in vivo data for LTC4. RESULTS CMVs were highly enriched and minimally contaminated based on marker enzyme activities. Uptake clearance among different species varied by approximately ten-fold (rat > dog = human > monkey) for LTC4 and less than two-fold for E2-Gluc. The lower uptake of LTC4 by human than rat CMVs may be attributed to a higher Km value for human than rat CMVs. Uptake of LTC4 or E2-Gluc by human CMVs showed little inter-subject variability (2-5-fold). Differences in in vitro uptake clearance (10-fold) between LTC4 and E2-Gluc in rat CMVs seemed to correlate with differences in their biliary clearance (4-fold) in rats, consistent with LTC4 and E2-Gluc being a high and a low clearance substrate, respectively. DISCUSSION A novel application of a Ultrafree filter cartridge/centrifugation method was developed to determine uptake in CMVs from different preclinical animal safety species and humans, and may represent a useful approach to study the mechanism of biliary excretion during drug discovery and development.
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Affiliation(s)
- A D Shilling
- Drug Safety and Metabolism, Wyeth Research RS3250, 500 Arcola Road, Collegeville, PA 19426, USA.
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Larsen S, Chng K, Battah F, Armstrong M, Hayward M, Leung L, Thomson S, Hennessy A, Rasko J. Cytokine-induced in vivo expansion and mobilization of marrow mesenchymal stem cells in nonhuman primates. Biol Blood Marrow Transplant 2006. [DOI: 10.1016/j.bbmt.2005.11.329] [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: 11/30/2022]
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Affiliation(s)
- L Leung
- Wilmer Eye Institute, Johns Hopkins Medical Institutes, Baltimore, MD 21287, USA
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40
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Barnett SW, Lu S, Srivastava I, Cherpelis S, Gettie A, Blanchard J, Wang S, Mboudjeka I, Leung L, Lian Y, Fong A, Buckner C, Ly A, Hilt S, Ulmer J, Wild CT, Mascola JR, Stamatatos L. The ability of an oligomeric human immunodeficiency virus type 1 (HIV-1) envelope antigen to elicit neutralizing antibodies against primary HIV-1 isolates is improved following partial deletion of the second hypervariable region. J Virol 2001; 75:5526-40. [PMID: 11356960 PMCID: PMC114265 DOI: 10.1128/jvi.75.12.5526-5540.2001] [Citation(s) in RCA: 188] [Impact Index Per Article: 8.2] [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: 11/20/2022] Open
Abstract
Partial deletion of the second hypervariable region from the envelope of the primary-like SF162 virus increases the exposure of certain neutralization epitopes and renders the virus, SF162DeltaV2, highly susceptible to neutralization by clade B and non-clade B human immunodeficiency virus (HIV-positive) sera (L. Stamatatos and C. Cheng-Mayer, J. Virol. 78:7840-7845, 1998). This observation led us to propose that the modified, SF162DeltaV2-derived envelope may elicit higher titers of cross-reactive neutralizing antibodies than the unmodified SF162-derived envelope. To test this hypothesis, we immunized rabbits and rhesus macaques with the gp140 form of these two envelopes. In rabbits, both immunogens elicited similar titers of binding antibodies but the modified immunogen was more effective in eliciting neutralizing antibodies, not only against the SF162DeltaV2 and SF162 viruses but also against several heterologous primary HIV type 1 (HIV-1) isolates. In rhesus macaques both immunogens elicited potent binding antibodies, but again the modified immunogen was more effective in eliciting the generation of neutralizing antibodies against the SF162DeltaV2 and SF162 viruses. Antibodies capable of neutralizing several, but not all, heterologous primary HIV-1 isolates tested were elicited only in macaques immunized with the modified immunogen. The efficiency of neutralization of these heterologous isolates was lower than that recorded against the SF162 isolate. Our results strongly suggest that although soluble oligomeric envelope subunit vaccines may elicit neutralizing antibody responses against heterologous primary HIV-1 isolates, these responses will not be broad and potent unless specific modifications are introduced to increase the exposure of conserved neutralization epitopes.
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Affiliation(s)
- S W Barnett
- Chiron Corporation, Emeryville, California 94608-2916, USA
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41
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Ng DK, Chow PY, Leung L, Chau KW, Chan E, Ho JC. A randomized controlled trial of azithromycin and amoxycillin/clavulanate in the management of subacute childhood rhinosinusitis. J Paediatr Child Health 2000; 36:378-81. [PMID: 10940175 DOI: 10.1046/j.1440-1754.2000.00526.x] [Citation(s) in RCA: 9] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Subacute childhood rhinosinusitis is a disorder commonly seen in children with allergic rhinitis. Antibiotics have been recommended as a major component of the treatment regime. The objective of the present study was to compare the effectiveness of a 3-day course of azithromycin and a 2-week course of amoxycillin/clavulanate in the treatment of subacute childhood rhinosinusitis. METHODOLOGY A randomized single-blinded control study of subacute rhinosinusitis was conducted, comparing a 3-day course of azithromycin and a 2-week course of amoxycillin/clavulanate. Inclusion criteria were children aged between 5 and 16 years, duration of nasal blockage or discharge between 30 and 120 days, and abnormal sinus radiographs. All enrolled children were prescribed budesonide nasal spray (Rhinocort Aqua Nasal Spray, Astra Pharmaceuticals, Sodertalje, Sweden) as adjuvant treatment. RESULTS Forty-two children were recruited into the study and one defaulted on follow-up. Failure occurred in 6 of 20 for the azithromycin group and 5 of 21 for the amoxycillin/clavulanate group. The odds ratio was 1.46 (95%CI 0.37-5. 80, P = 0.73). No relapse occurred in azithromycin group and 5 of 21 in amoxycillin/clavulanate group. The odds ratio was 0.16 (95%CI 0. 017-1.51, P = 0.18). Both antibiotics were well tolerated, however, two children, one from each group, complained of mild transient epigastric discomfort. CONCLUSIONS This small study did not provide evidence of a difference between 14 days of amoxycillin/clavulanate and 3 days of azithromycin. Larger studies will be needed to determine which, if any, antibiotic regimen should be used in treating subacute childhood rhinosinusitis.
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Affiliation(s)
- D K Ng
- Departments of Paediatrics and Radiology, Kwong Wah Hospital, Hong Kong, China.
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Small TN, Leung L, Stiles J, Kiehn TE, Malak SA, O'Reilly RJ, Sepkowitz K. Disseminated toxoplasmosis following T cell-depleted related and unrelated bone marrow transplantation. Bone Marrow Transplant 2000; 25:969-73. [PMID: 10800065 DOI: 10.1038/sj.bmt.1702370] [Citation(s) in RCA: 42] [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: 11/09/2022]
Abstract
More than 95% of reported cases of disseminated toxoplasmosis following BMT have occurred following an unmodified transplant. Most have been fatal, diagnosed at autopsy and without antemortem institution of specific therapy. From 1989 to 1999, we identified 10 cases of disseminated toxoplasmosis, in 463 consecutive recipients of a T cell-depleted (TCD) BMT. Transplants were from an unrelated donor (n = 5), an HLA-matched sibling (n = 4) or an HLA-mismatched father (n = 1). In 40%, both the donor and recipient had positive IgG titers against T. gondii pre-transplant; in 30%, only the recipient was sero-positive. Three recipients of an unrelated TCD BMT developed toxoplasmosis despite both donor and host testing negative pretransplant. All 10 patients presented with high grade fever. CNS involvement ultimately occurred in seven patients, with refractory respiratory failure and hypotension developing in nine. Eight of 10 cases were found only at autopsy, involving the lungs (n = 7), heart (n = 5), GI tract (n = 5), brain (n = 8), liver and/or spleen (n = 5). The only survivor, treated on the day of presentation with fever and headache, was diagnosed by detection of T. gondii DNA by polymerase chain reaction (PCR) performed on the blood and spinal fluid. This study demonstrates the similar incidence of toxoplasmosis following TCD BMT and that reported post T cell-replete BMT, and underscores the need for rapid diagnostic tests in an effort to improve outcome.
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Affiliation(s)
- T N Small
- Department of Pediatrics (Bone Marrow Transplant Service),Memorial Sloan-Kettering Cancer Center, New York City, NY 10021, USA
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Widera G, Austin M, Rabussay D, Goldbeck C, Barnett SW, Chen M, Leung L, Otten GR, Thudium K, Selby MJ, Ulmer JB. Increased DNA vaccine delivery and immunogenicity by electroporation in vivo. J Immunol 2000; 164:4635-40. [PMID: 10779767 DOI: 10.4049/jimmunol.164.9.4635] [Citation(s) in RCA: 404] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
DNA vaccines have been demonstrated to be potent in small animals but are less effective in primates. One limiting factor may be inefficient uptake of DNA by cells in situ. In this study, we evaluated whether cellular uptake of DNA was a significant barrier to efficient transfection in vivo and subsequent induction of immune responses. For this purpose, we used the technique of electroporation to facilitate DNA delivery in vivo. This technology was shown to substantially increase delivery of DNA to cells, resulting in increased expression and elevated immune responses. The potency of a weakly immunogenic hepatitis B surface Ag DNA vaccine was increased in mice, as seen by a more rapid onset and higher magnitude of anti-hepatitis B Abs. In addition, the immunogenicity of a potent HIV gag DNA vaccine was increased in mice, as seen by higher Ab titers, a substantial reduction in the dose of DNA required to induce an Ab response, and an increase in CD8+ T cell responses. Finally, Ab responses were enhanced by electroporation against both components of a combination HIV gag and env DNA vaccine in guinea pigs and rabbits. Therefore, cellular uptake of DNA is a significant barrier to transfection in vivo, and electroporation appears able to overcome this barrier.
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MESH Headings
- AIDS Vaccines/administration & dosage
- AIDS Vaccines/genetics
- AIDS Vaccines/immunology
- Animals
- Dose-Response Relationship, Immunologic
- Electroporation
- Female
- Gene Products, env/genetics
- Gene Products, env/immunology
- Gene Products, gag/genetics
- Gene Products, gag/immunology
- Guinea Pigs
- HIV Antibodies/biosynthesis
- HIV-1/genetics
- HIV-1/immunology
- Hepatitis B Antibodies/biosynthesis
- Hepatitis B Surface Antigens/genetics
- Hepatitis B Surface Antigens/immunology
- Hepatitis B Vaccines/administration & dosage
- Hepatitis B Vaccines/genetics
- Hepatitis B Vaccines/immunology
- Injections, Intramuscular
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Nude
- Rabbits
- Vaccines, DNA/administration & dosage
- Vaccines, DNA/genetics
- Vaccines, DNA/immunology
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Affiliation(s)
- G Widera
- Vaccines Research, Chiron Corporation, Emeryville, CA 94608, USA
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Cho P, Leung L, Lam A, Choi A. Tear break-up time: clinical procedures and their effects. Ophthalmic Physiol Opt 1998; 18:319-24. [PMID: 9829104] [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: 02/09/2023]
Abstract
Three successive (representative) values of fluorescein-instillation TBUT (tear break-up time) were obtained from a group of young Hong Kong (HK)-Chinese. The median TBUT1, TBUT2 and TBUT3 were 3.2, 3.8 and 4.5 sec, respectively. Wilcoxon signed-rank tests showed that TBUT1 was significantly different from TBUT2 and TBUT3, but there was no difference between TBUT2 and TBUT3. It is therefore important, when measuring the TBUT, to specify which TBUT value was taken as the representative TBUT. Fluorescein was reapplied about six min after the first application, and the TBUT value re-determined (TBUTR). The median TBUTR was not significantly different from TBUT1. The subjects were requested to return another day and TBUT values (TBUTW) were determined, with the subjects opening their eyes as wide as possible, such that the palpebral aperture size was increased. The mean +/- SD normal palpebral aperture size was 10.0 +/- 1.3 mm, and the mean +/- SD palpebral aperture size with the eyes wide open was 11.4 +/- 1.5 mm. The median TBUTW (3.6 sec) was significantly longer than the median TBUT1 (3.0 sec), but this difference appeared to be due to the extremely long TBUTW of one subject; no significant difference was found between the median TBUTW (3.4 sec) and TBUT1 (2.8 sec) when data from this subject were excluded. There was no significant correlation between changes in palpebral size and TBUT value.
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Affiliation(s)
- P Cho
- Department of Optometry & Radiography, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
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Le T, Leung L, Carroll WL, Schibler KR. Regulation of interleukin-10 gene expression: possible mechanisms accounting for its upregulation and for maturational differences in its expression by blood mononuclear cells. Blood 1997; 89:4112-9. [PMID: 9166853] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Interleukin-10 (IL-10) downmodulates phagocytic immune responses and accentuates humoral responses. Human neonates exhibit broad immune deficits that parallel actions of IL-10. We postulated that IL-10 production would be diminished in neonatal blood cells. We found that IL-10 production by lipopolysaccharide-stimulated peripheral blood mononuclear cells (PBMNCs) in vitro was greater by adult cells than by term cells and preterm cells. Additional studies were undertaken to identify mechanisms responsible for the developmental differences in IL-10 gene expression. IL-10 transcription was present in freshly isolated adult and neonatal cells in the absence of detectable levels of transcript. Transcription rates were not different between adult and neonatal cells. IL-10 transcripts were approximately 40% more abundant in adult cells than in term cells and were consistent with differences in secreted protein; however, no differences were noted in mRNA stability. IL-10 half-life was 60 minutes for both adult and term PBMNCs. We conclude that up-regulation of IL-10 gene expression in PBMNCs is modulated at the post-transcriptional level, that IL-10 protein production and mRNA content are greater in activated cells from adults compared with those from neonates, and that maturational differences in IL-10 expression are not due to differences in transcription rate or mRNA stability. Maturational differences in IL-10 expression might be due to differences in subpopulations of cytokine-producing cells or differences in nucleo-cytoplasmic transport.
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Affiliation(s)
- T Le
- Department of Pediatrics, Clinical Research Center, University of Utah School of Medicine, Salt Lake City 84132, USA
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Wu PM, Chua DT, Sham JS, Leung L, Kwong DL, Lo M, Yung A, Choy DT. Tumor control probability of nasopharyngeal carcinoma: a comparison of different mathematical models. Int J Radiat Oncol Biol Phys 1997; 37:913-20. [PMID: 9128969 DOI: 10.1016/s0360-3016(96)00588-3] [Citation(s) in RCA: 25] [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: 02/04/2023]
Abstract
PURPOSE Radiation dose and tumor volume are factors known to affect the local control of a given type of tumor. Local tumor control is a major factor to consider when a treatment plan is evaluated. This article reports the correlation between tumor control probability, dose, and volume in a retrospective study of 142 patients with nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS The tumor volume was outlined and calculated from a computed tomographic scan. Patients were categorized according to tumor volume and radiation dose received in treatment. Local control rate was calculated for each category by the Kaplan-Meier method. Mathematical models were fitted to correlate the local control rate, dose, and volume. Both empirical and mechanistic approaches were attempted; the former included logistic models with two and three parameters, and the latter, the formulation from Brenner and Bentzen with a radiobiological basis. RESULTS Brenner's model estimated alpha at 0.041 Gy(-1) with 95% confidence limits (-0.032, 0.113) Gy(-1). The volume dependent constant h was estimated at 0.160 cm(-3) with 95% confidence limits (-0.729, 1.048) cm(-3). The Pearson correlation coefficient was 0.64. The magnitude and sign of the fitted parameters were reasonable and consistent with reported clinical experience. The other models were fitted with slightly better goodness of fit (r = 0.65 - 0.68), but with less interpretable parameters. CONCLUSION Brenner's model is considered appropriate for a description of the dose and volume effect on the local control of the NPC. It could be used in combination with normal tissue complication probability for treatment plan evaluation to optimize treatment results.
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Affiliation(s)
- P M Wu
- Department of Radiotherapy and Oncology, University of Hong Kong, Queen Mary Hospital
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47
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Abstract
PURPOSE To demonstrate that "reverse iontophoresis" can be used to noninvasively obtain information about systemic glucose levels in vivo in humans. METHODS The passage of current across the skin in vivo drives ions into the tissue, from the electrode chambers positioned on the skin surface, and simultaneously pulls ions from the body in the opposite direction. Because of the net negative charge on the skin, under normal conditions, the membrane is permselective to cations, and a potential gradient also results, therefore, in electroosmotic convection of solvent in the direction of counterion flow (i.e., from anode to cathode). Thus, it is also possible to enhance the transport of polar, yet uncharged, species using iontophoresis. In an earlier study, the in vitro extraction of glucose, by "reverse iontophoresis" was established, and extension of the approach to an in vivo model was indicated. The idea has therefore been further explored in vivo in humans. RESULTS Using small, simple, prototypical electrode chambers, attached to the ventral forearm surface, direct current iontophoresis at 0.25 mA/cm2 for periods of up to 1 hour, and a sensitive analytical procedure to measure the quantities of glucose extracted, it has been shown that iontophoretic sampling of glucose is feasible. However, the shorter periods (15 minutes or less) of extraction considered yield results which are "contaminated" (it is believed) by glucose that is a product of lipid metabolism within the skin. While this material is expected to complicate the initial calibration of the approach, the problem is effectively resolved within one hour, by which time the glucose arriving in the electrode chambers on the skin surface is expected to directly reflect the subcutaneous tissue concentration. CONCLUSIONS Based upon these initial observations, further investigation can now be directed towards optimization of electroosmotic flow and sampling time, improved reproducibility and the development of a practical assay methodology.
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Affiliation(s)
- G Rao
- Department of Pharmacy, University of California, San Francisco 94143-0446, USA
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48
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Miller LS, Liu JB, Colizzo FP, Ter H, Marzano J, Barbarevech C, Helwig K, Leung L, Goldberg BB, Hedwig K [corrected to Helwig K]. Correlation of high-frequency esophageal ultrasonography and manometry in the study of esophageal motility. Gastroenterology 1995; 109:832-7. [PMID: 7657111 DOI: 10.1016/0016-5085(95)90391-7] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND & AIMS No studies correlate manometric measurements with morphological changes during the esophageal peristaltic sequence. The aim of this study was to develop and use a system for sonographically imaging the esophageal wall while simultaneously recording esophageal pressure changes. METHODS An ultrasonography transducer attached to a manometric probe was used to evaluate the esophagus. RESULTS Four sonographic phases of an esophageal peristaltic sequence were identified. The esophageal lumen was not open at rest in phase 1 (resting), increased to a maximum mean circumference of 4.90 +/- 0.57 cm in phase 2 (passive distention), and returned to a closed position in phases 3 (contraction) and 4 (relaxation). The muscle layers of the esophageal wall were baseline resting width in phase 1, decreased in width during phase 2, increased and reached maximum mean widths during phase 3, and returned to baseline widths during phase 4. The measurement of esophageal intraluminal pressure remained at a baseline resting level during phases 1 and 2, increased to a maximum mean peak of 67.95 +/- 9.18 mm Hg during phase 3, and returned to baseline during phase 4. CONCLUSIONS A combined ultrasonography transducer/manometry probe was used to dynamically and simultaneously evaluate esophageal wall motion, muscle thickness, and esophageal pressure changes during peristalsis.
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Affiliation(s)
- L S Miller
- Department of Medicine, Temple University Hospital, Philadelphia, Pennsylvania, USA
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49
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Abstract
Platelet aggregation is one of the best understood examples of adhesive cell-cell interactions. The platelet glycoprotein IIb/IIIa membrane receptor plays a pivotal role in platelet aggregation through its binding of fibrinogen. It is intimately involved in the pathogenesis of platelet-rich arterial thromboses. The IIb/IIIa receptor is an important target for recently described novel antiplatelet therapeutics. The development and clinical evaluation of this class of antiplatelet therapeutics are reviewed in this article.
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Affiliation(s)
- S Coutré
- Gilead Sciences, Foster City, California 94404, USA
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50
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Bommannan DB, Tamada J, Leung L, Potts RO. Effect of electroporation on transdermal iontophoretic delivery of luteinizing hormone releasing hormone (LHRH) in vitro. Pharm Res 1994; 11:1809-14. [PMID: 7899247 DOI: 10.1023/a:1018983804635] [Citation(s) in RCA: 113] [Impact Index Per Article: 3.8] [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: 01/27/2023]
Abstract
Electroporation, the creation of transient, enhanced membrane permeability using short duration (microseconds to millisecond) electrical pulses, can be used to increase transdermal drug delivery. The effect of an (electroporative) electric pulse (1000 V, tau = 5 msec) on the iontophoretic transport of LHRH through human skin was studied in vitro. Fluxes achieved with and without a pulse under different current densities (0- 4 mA/cm2) were compared. The results indicated that the application of a single pulse prior to iontophoresis consistently yielded higher fluxes (5-10 times the corresponding iontophoretic flux). For example, at 0.5 mA/cm2 fluxes were 0.27 +/- 0.08 and 1.62 +/- 0.05 micrograms/hr/cm2 without and with the pulse, respectively. At each current density studied, the LHRH flux decreased after iontophoresis, approaching pre-treatment values. The results show that electroporation can significantly and reversibly increase the flux of LHRH through human skin. These results also indicate the therapeutic utility of using electroporation for enhanced transdermal transport.
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Affiliation(s)
- D B Bommannan
- Cygnus Therapeutic Systems, Redwood City, California 94063
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