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

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.

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Oesophageal protection during AF ablation: real world registry data and mechanisms behind the therapeutic effect of tissue cooling

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.

A registry review of 2532 catheter ablations for atrial fibrillation using active thermal protection

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

Cost-effectiveness of catheter ablation versus medical therapy for the treatment of atrial fibrillation in the United Kingdom

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.

Patient outcomes after AF ablation using Ablation Index technology with oesophageal protection: insight from the IMPACT study

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)

1202 Validation Of A Novel Wearable Home Sleep Testing Device For Assessment Of Obstructive Sleep Apnea

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.

Author Correction: Lysyl oxidase drives tumour progression by trapping EGF receptors at the cell surface

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Anti-metastatic Inhibitors of Lysyl Oxidase (LOX): Design and Structure-Activity Relationships

Lysyl oxidase (LOX) is a secreted copper-dependent amine oxidase that cross-links collagens and elastin in the extracellular matrix and is a critical mediator of tumor growth and metastatic spread. LOX is a target for cancer therapy, and thus the search for therapeutic agents against LOX has been widely sought. We report herein the medicinal chemistry discovery of a series of LOX inhibitors bearing an aminomethylenethiophene (AMT) scaffold. High-throughput screening provided the initial hits. Structure-activity relationship (SAR) studies led to the discovery of AMT inhibitors with sub-micromolar half-maximal inhibitory concentrations (IC50) in a LOX enzyme activity assay. Further SAR optimization yielded the orally bioavailable LOX inhibitor CCT365623 with good anti-LOX potency, selectivity, pharmacokinetic properties, as well as anti-metastatic efficacy.

Bridging the gap: An evaluation of self-paced online transition modules for advanced pharmacy practice experience students

BACKGROUND AND PURPOSE

A three module online self-paced educational resource was developed for entry to practice students transitioning from the classroom to their inpatient practicums. The objective of this study was to determine the benefits of the transition modules on students' self-perceived competency as related to onsite performance and reduction in anxiety during their inpatient practicum.

EDUCATIONAL ACTIVITY AND SETTING

Evaluations of the three transition modules were conducted in two phases via electronic surveys distributed to final year advanced pharmacy practice students and focus group members including faculty, pharmacy practice educators, and pharmacy residents.

FINDINGS

Based on our findings, the modules addressed common learning needs. While 69.7% of student respondents from Phase II of the evaluation found the modules to have positively impacted their onsite performance, only 24.7% believed the modules reduced their anxiety.

DISCUSSION

The study indicates that students found the modules to be relevant to inpatient practice and of appropriate difficulty. Although most students perceived the modules to enhance performance on practicum, student anxiety levels appeared to remain unchanged.

SUMMARY

Based on feedback and results, it may be beneficial to expose students to transition modules earlier in the curriculum in tandem with other inpatient preparatory activities. The results from this study may be of interest or benefit other universities and healthcare educators pursuing work on transition activities.

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

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.

Improving the stability of 11C-labeled L-methionine with ascorbate

Background

Carbon-11 labeled L-methionine (¹¹C–MET) is a popular tracer used in the clinic for imaging brain tumors with positron emission tomography. However, the stability of ¹¹C–MET in its final formulation is not well documented in literature. Recently, we observed fast degradation of HPLC-purified ¹¹C–MET over time, and systematic investigation was conducted to identify the cause.

Results

In this study, we verified the degraded product as ¹¹C–labeled methionine sulfoxide (¹¹C–METSO). To minimize oxidation, ascorbate (100 ppm) was added to the HPLC eluant, and the resulting HPLC-purified ¹¹C–MET was stable in the final formulation solution without noticeable degradation for up to 1 h after the end of synthesis.

Conclusions

Our data suggest that to minimize degradation, ascorbate can be added to the ¹¹C–MET formulation solution especially if it is not administered into patients soon after the end of synthesis.

Electronic supplementary material

The online version of this article (10.1186/s41181-017-0032-x) contains supplementary material, which is available to authorized users.

Lysyl oxidase drives tumour progression by trapping EGF receptors at the cell surface

Lysyl oxidase (LOX) remodels the tumour microenvironment by cross-linking the extracellular matrix. LOX overexpression is associated with poor cancer outcomes. Here, we find that LOX regulates the epidermal growth factor receptor (EGFR) to drive tumour progression. We show that LOX regulates EGFR by suppressing TGFβ1 signalling through the secreted protease HTRA1. This increases the expression of Matrilin2 (MATN2), an EGF-like domain-containing protein that traps EGFR at the cell surface to facilitate its activation by EGF. We describe a pharmacological inhibitor of LOX, CCT365623, which disrupts EGFR cell surface retention and delays the growth of primary and metastatic tumour cells in vivo. Thus, we show that LOX regulates EGFR cell surface retention to drive tumour progression, and we validate the therapeutic potential of inhibiting this pathway with the small molecule inhibitor CCT365623.

A randomized controlled trial to determine the efficacy of a high carbohydrate and high protein ready-to-eat food product for weight loss

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.

Ion-scale spectral break of solar wind turbulence at high and low beta

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.

Plasma Epstein-Barr viral DNA load at midpoint of radiotherapy course predicts outcome in advanced-stage nasopharyngeal carcinoma

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.

Subinguinal microsurgical varicocelectomy for male factor subfertility: ten-year experience

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.

Thoracoscopic resection of congenital cystic lung lesions is associated with better post-operative outcomes

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.

Synthesis and crystallographic analysis of meso-2,3-difluoro-1,4-butanediol and meso-1,4-dibenzyloxy-2,3-difluorobutane

A large-scale synthesis of meso-2,3-difluoro-1,4-butanediol in 5 steps from (Z)-but-2-enediol is described. Crystallographic analysis of the diol and the corresponding benzyl ether reveals an anti conformation of the vicinal difluoride moiety. Monosilylation of the diol is high-yielding but all attempts to achieve chain extension through addition of alkyl Grignard and acetylide nucleophiles failed.

The synthesis and in vivo evaluation of 2',2'-difluoro KRN7000

The synthesis of 2',2'-difluoro KRN7000 is described. In vivo evaluation demonstrates that this fluorinated glycolipid induces CD1d-dependent TCR activation of NKT cells, with a bias towards Th2 cytokine production.

Synthesis and in vivo evaluation of 4-deoxy-4,4-difluoro-KRN7000

The synthesis of 4-deoxy-4,4-difluoro-KRN7000 starting from phytosphingosine is described. Key steps include a regioselective benzylation of azidophytosphingosine and a deoxofluor-mediated fluorination of the corresponding 4-ketone. This fluorination failed completely when the adjacent 3-OH was protected as benzyl ether but proceeded well when a benzoyl group was used. The biological evaluation reveals a bias toward Th1 cytokine induction upon Natural Killer T cell activation.

Comparison of morphology and mechanical properties of PLGA bioscaffolds

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.

Novel mutations and mutation pattern of epidermal growth factor receptor (EGFR) gene in Chinese patients with primary lung adenocarcinoma

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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]

Use of canalicular membrane vesicles (CMVs) from rats, dogs, monkeys and humans to assess drug transport across the canalicular membrane

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.

Human epidermal growth factor enhances healing of diabetic foot ulcers

OBJECTIVE

To study the healing effect of recombinant human epidermal growth factor (hEGF) on diabetic foot ulcers.

RESEARCH DESIGN AND METHODS

A total of 127 consecutive patients were screened and 61 diabetic subjects were recruited into this double-blind randomized controlled study. Predetermined criteria were used for diagnosis and classification of the diabetic wound. The patients were randomized into three groups. All patients attended our Diabetes Ambulatory Care Center every other week for joint consultation with the diabetologist and the podiatrist. Group 1 (control) was treated with Actovegin 5% cream (Actovegin), group 2 with Actovegin plus 0.02% (wt/wt) hEGF, and group 3 with Actovegin plus 0.04% (wt/wt) hEGF. The study end point was the complete closure of the wound. Failure to heal was arbitrarily defined as incomplete healing after 12 weeks.

RESULTS

Final data were obtained from 61 patients randomly assigned into three groups. The mean ages of the patients, wound sizes, wound duration, metabolic measurements, and comorbidities were comparable within groups, except that group 3 had more female patients. Mean follow-up for the patients was 24 weeks. Data were cutoff at 12 weeks, and results were analyzed by intention to treat. After 12 weeks, in group 1 (control) eight patients had complete healing, two patients underwent toe amputation, and nine had nonhealing ulcers. In group 2 (0.02% [wt/wt] hEGF) 12 patients experienced wound healing, 2 had toe amputations, and 7 had nonhealing ulcers. Some 20 of 21 patients in group 3 (0.04% [wt/wt] hEGF) showed complete wound healing. Healing rates were 42.10, 57.14, and 95% for the control, 0.02% (wt/wt) hEGF, and 0.04% (wt/wt) hEGF groups, respectively. Kaplan-Meier survival analysis suggested that application of cream with 0.04% (wt/wt) hEGF caused more ulcers to heal by 12 weeks and increased the rate of healing compared with the other treatments (log-rank test, P = 0.0003).

CONCLUSIONS

Our data support the contention that application of hEGF-containing cream, in addition to good foot care from a multidisciplinary team, significantly enhances diabetic foot ulcer wound healing and reduces the healing time.

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

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.

A randomized controlled trial of azithromycin and amoxycillin/clavulanate in the management of subacute childhood rhinosinusitis

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.

Disseminated toxoplasmosis following T cell-depleted related and unrelated bone marrow transplantation

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.

Increased DNA vaccine delivery and immunogenicity by electroporation in vivo

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.

Tear break-up time: clinical procedures and their effects

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.