Transseptal Mitral Valve-in-Valve-in-Valve

•Transseptal MV implantation is performed for many indications. •Previous ViV procedures do not preclude further ViV insertion. •Appropriate sizing of transseptal MVs is essential to reduce complications. •Multimodality cardiac imaging is essential for valve placement and follow-up. •Frequent serial TTE is recommended for follow-up.

Correlative Light and Electron Cryo-Microscopy Workflow Combining Micropatterning, Ice Shield, and an In-Chamber Fluorescence Light Microscope

In situ cryo-electron tomography (cryo-ET) is the most current, state-of-the-art technique to study cell machinery in its hydrated near-native state. The method provides ultrastructural details at sub-nanometer resolution for many components within the cellular context. Making use of recent advances in sample preparation techniques and combining this method with correlative light and electron microscopy (CLEM) approaches have enabled targeted molecular visualization. Nevertheless, the implementation has also added to the complexity of the workflow and introduced new obstacles in the way of streamlining and achieving high throughput, sample yield, and sample quality. Here, we report a detailed protocol by combining multiple newly available technologies to establish an integrated, high-throughput, optimized, and streamlined cryo-CLEM workflow for improved sample yield. Key features • PRIMO micropatterning allows precise cell positioning and maximum number of cell targets amenable to thinning with cryo focused-ion-beam-scanning electron microscopy. • CERES ice shield ensures that the lamellae remain free of ice contamination during the batch milling process. • METEOR in-chamber fluorescence microscope facilitates the targeted cryo focused-ion-beam (cryo FIB) milling of these targets. • Combining the three technologies into one cryo-CLEM workflow maximizes sample yield, throughput, and efficiency. Graphical overview.

Diagnostic application of intraoral ultrasonography to assess furcation involvement in mandibular first molars

OBJECTIVES

The objectives were to clarify if intraoral ultrasonography (USG) is: (1) more accurate than conventional periodontal examinations in detection of furcation involvement, and (2) comparable to conventional periodontal examinations in accurate horizontal classification of furcation involvement in comparison to cone beam computed tomography (CBCT).

METHODS

The buccal furcation in 61 lower first molars were evaluated with conventional periodontal examinations, intraoral USG and CBCT. The presence and classification of the horizontal depth of furcation involvement were defined clinically by assessment with a Nabers periodontal probe and a periapical radiograph with reference to the bone loss under the fornix. The horizontal depth of furcation involvement was measured in intraoral USG and CBCT images. Based on the measurements, presence diagnosis and horizontal classification were performed. Results from conventional periodontal examinationsand intraoral USG were compared with those from CBCT.

RESULTS

κ value (κ) for agreement of presence diagnosis of furcation involvement between intraoral USG and CBCT was 0.792, while agreement with conventional periodontal examinations was 0.225. Diagnostic accuracy of intraoral USG exhibited higher values (sensitivity: 98.3%, accuracy: 98.4 %) than conventional periodontal examinations (81.4% and 81.9 %). Weighted κ statistics showed substantial agreement in the classification between intraoral USG and CBCT (κ = 0.674). High agreement (ICC: 0.914) for the measurement of horizontal depth of furcation involvement was found between intraoral USG and CBCT.

CONCLUSIONS

Intraoral USG may be a reliable diagnostic tool for assessment of furcation involvement of mandibular molars with a similar performance to CBCT, but without ionizing radiation.

Uncovering and engineering the mechanical properties of the adhesion GPCR ADGRG1 GAIN domain

Key cellular functions depend on the transduction of extracellular mechanical signals by specialized membrane receptors including adhesion G-protein coupled receptors (aGPCRs). While recently solved structures support aGPCR activation through shedding of the extracellular GAIN domain, the molecular mechanisms underpinning receptor mechanosensing remain poorly understood. When probed using single-molecule atomic force spectroscopy and molecular simulations, ADGRG1 GAIN dissociated from its tethered agonist at forces significantly higher than other reported signaling mechanoreceptors. Strong mechanical resistance was achieved through specific structural deformations and force propagation pathways under mechanical load. ADGRG1 GAIN variants computationally designed to lock the alpha and beta subdomains and rewire mechanically-induced structural deformations were found to modulate the GPS-Stachel rupture forces. Our study provides unprecedented insights into the molecular underpinnings of GAIN mechanical stability and paves the way for engineering mechanosensors, better understanding aGPCR function, and informing drug-discovery efforts targeting this important receptor class.

Acute Bioprosthetic Mitral Valve Failure Diagnosed Using Point-of-Care Ultrasound Leading to Prompt Treatment and Good Outcome

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Acute bioprosthetic mitral valve failure is a medical emergency.

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POCUS can confirm the diagnosis along with a good history and physical exam.

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Early diagnosis and prompt multidisciplinary treatment will deliver the best outcome.

Comparison of ophthalmic artery Doppler with PlGF and sFlt-1/PlGF ratio at 35-37 weeks' gestation in prediction of imminent pre-eclampsia

OBJECTIVE

To compare the predictive performance for delivery with pre-eclampsia (PE) at < 3 weeks and at any stage after assessment at 35 + 0 to 36 + 6 weeks' gestation of serum placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1)/PlGF ratio with that of a competing-risks model utilizing maternal risk factors, mean arterial pressure (MAP) and ophthalmic artery peak systolic velocity (PSV) ratio.

METHODS

This was a prospective observational study of women attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation. This visit included recording of maternal demographic characteristics and medical history, ultrasound examination of fetal anatomy and growth, assessment of flow velocity waveforms from the maternal ophthalmic arteries and measurement of MAP, serum PlGF and serum sFlt-1. The performance of screening for delivery with PE at < 3 weeks and at any time after the examination was assessed using areas under the receiver-operating-characteristics curves and detection rates (DRs), at a 10% false-positive rate (FPR). McNemar's test was used to compare DRs, at a 10% FPR, between screening by PlGF concentration, the sFlt-1/PlGF concentration ratio and the competing-risks model utilizing maternal risk factors, MAP and ophthalmic artery PSV ratio. Model-based estimates of screening performance for different methods of screening were also produced.

RESULTS

The study population of 2338 pregnancies contained 75 (3.2%) cases that developed PE, including 30 (1.3%) that delivered with PE at < 3 weeks from assessment, and 2263 cases unaffected by PE. The DR of PE at < 3 weeks from assessment, at a 10% FPR, of sFlt-1/PlGF ratio (70.0% (95% CI, 50.6-85.3%)) was superior to that of PlGF (50.0% (95% CI, 31.3-68.7%)) or PSV ratio (56.7% (95% CI, 37.4-74.5%)) but inferior to that of the combination of maternal risk factors, MAP multiples of the median (MoM) and PSV ratio delta (96.7% (95% CI, 82.8-99.9%)). Similarly, the DR of PE at any stage after assessment of sFlt-1/PlGF ratio (62.7% (95% CI, 50.7-73.6%)) was superior to that of PlGF (52.0% (95% CI, 40.2-63.7%)) or PSV ratio (41.3% (95% CI, 30.1-53.3%)) but inferior to that of the combination of maternal risk factors, MAP MoM and PSV ratio delta (78.7% (95% CI, 67.7-87.3%)). The empirical results for DR at a 10% FPR were consistent with the modeled results, both for delivery with PE at < 3 weeks and at any time after assessment.

CONCLUSION

Ophthalmic artery Doppler in combination with maternal risk factors and blood pressure could potentially replace measurement of PlGF and sFlt-1/PlGF ratio in the prediction of imminent PE. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Impact of inter-vendor variability on evaluation of left ventricular mechanical dispersion

PURPOSE

Left ventricular mechanical dispersion (LVMD) is a novel speckle tracking parameter for prognostic assessment of arrhythmic risk prediction. There is growing evidence to support its use in a variety of cardiomyopathic processes. There is paucity of data addressing any presence of inter-vendor discrepancies for LVMD. The aim of this study was to assess inter-vendor variability of LVMD in vendor specific software (VSS) and vendor independent software (VIS) in subjects with preserved and reduced left ventricular function.

METHODS

Fifty-nine subjects (14 normal subjects and 45 subjects with cardiac disease) were recruited and 2D speckle tracking echocardiographic images were acquired on two different ultrasound machines (GE and Philips). LVMD was measured by two different VSS (EchoPac GE and QLAB Philips) and one VIS (TomTec Arena).

RESULTS

There was significant bias and wide limits of agreement (LOA) in the overall cohort observed between two different VSS (17.6 ms; LOA: -29.6 to 64.8; r: .47). There was acceptable bias and narrower LOA with good agreement for LVMD between images obtained on different vendors when performed on VIS (-3.1 ms; LOA: -27.6 to 21.4; r: .75). QLAB LVMD was consistently higher than GE LVMD and TomTec LVMD in both preserved and reduced left ventricular function. LVMD measurements have high intra-vendor reproducibility with excellent inter and intra-observer agreement.

CONCLUSIONS

There was acceptable bias and narrower LOA for LVMD assessment on a VIS. Inter-vendor variability exists for LVMD assessment between VSS. Serial measurements of LVMD should be performed using a single vendor for consistent and reliable results.

Closed-Incision Negative Pressure Wound management Following Midline Laparotomy in Gynecological Oncology Operations: A Feasibility Pilot Study

Introduction

Surgical site infections (SSIs) are a cause of considerable morbidity and mortality in healthcare. Increasingly, closed-incision negative pressure wound therapy (ciNPWT) is being studied as a potential method of reducing incidence of SSI with conflicting results in the literature. Few studies however have looked at its use in the field of gynecological oncology.

Objectives

We aimed to compare the incidence of SSI when using ciNPWT dressings versus conventional dressings in gynecological oncology patients undergoing midline laparotomies.

Methods

This was a pilot study involving 14 patients receiving the ciNPWT dressing and 26 control patients. All patients were followed up for a period of 30 days. We used the American College of Surgeons (ACS) risk calculator to estimate each patient’s risk of SSI in order to risk stratify the groups.

Results

The incidence of wound infection was 21% (3/14) in the ciNPWT group and 23% (6/26) in the control group (p=0.886). The ciNPWT group was found to be at significantly higher risk for SSI as calculated by the ACS tool (8.8% ciNPWT, 6% control, p=0.004). After stratifying for this difference in risk, still no significant difference in incidence of SSI was found between the two groups (27% (3/11) ciNPWT, 29% (2/7) control p=0.929).

Conclusion

The incidence of SSI does not appear to decrease by the prophylactic use of the closed-incision negative pressure wound dressing. 

Improved Constraints on Primordial Gravitational Waves using Planck, WMAP, and BICEP/Keck Observations through the 2018 Observing Season

We present results from an analysis of all data taken by the BICEP2, Keck Array, and BICEP3 CMB polarization experiments up to and including the 2018 observing season. We add additional Keck Array observations at 220 GHz and BICEP3 observations at 95 GHz to the previous 95/150/220  GHz dataset. The Q/U maps now reach depths of 2.8, 2.8, and 8.8  μK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈600 square degrees at 95 GHz and ≈400 square degrees at 150 and 220 GHz. The 220 GHz maps now achieve a signal-to-noise ratio on polarized dust emission exceeding that of Planck at 353 GHz. We take auto- and cross-spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz and evaluate the joint likelihood of the spectra versus a multicomponent model of lensed ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and no longer requires a prior on the frequency spectral index of the dust emission taken from measurements on other regions of the sky. This model is an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.036 at 95% confidence. Running maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.009. These are the strongest constraints to date on primordial gravitational waves.

Absence of fetal heart rate cycling on the intrapartum cardiotocograph (CTG) is associated with intrapartum pyrexia and lower Apgar scores

BACKGROUND

Cycling consists of alternating periods of reduced and normal fetal heart variability, reflecting changes in fetal behavioral states. Occurrence of active and quiet sleep cycles is considered to be a hallmark of fetal autonomic nervous system integrity, demonstrating healthy interaction between the parasympathetic and sympathetic nervous systems. Cycling is an overlooked feature in most international cardiotocography (CTG) guidelines. The authors tested the hypothesis that fetuses showing no cycling in the intrapartum period have poorer outcomes.

AIM

To investigate whether the absence of cycling at the commencement of intrapartum fetal monitoring is associated with poorer neonatal outcomes (umbilical arterial cord pH, Apgar scores and neonatal unit admission).

METHODS

Analysis of a database of sequentially acquired intrapartum CTG traces from a single center. Only cases of singleton pregnancies over 36 weeks gestation in cephalic presentation with recorded umbilical artery cord pH were considered. Neonatal outcomes were assessed based on umbilical cord artery pH, Apgar ≤7 at 5 min and unexpected admission to the neonatal unit. Intrapartum pyrexia, presence of meconium-stained amniotic fluid and mode of delivery were also recorded.

RESULTS

A total of 684 cases were analyzed. Absence of cycling from the beginning of the intrapartum CTG recording was noted in 5% of cases. Cases with no cycling were more likely to have maternal pyrexia (≥37.8 °C) (p = .006) and Apgars ≤7 at 5 min (p = .04). There was an association between increasing baseline fetal heart rate and the proportion of cases with no cycling. There was no significant difference between the two groups with regard to the mode of delivery or umbilical cord arterial pH <7.05 (p = .53).

CONCLUSION

Absence of cycling is associated with intrapartum maternal pyrexia and fetuses with the absence of cycling are more likely to have poorer perinatal outcomes measured by Apgar ≤ 7 at 5 min, despite no association with fetal acidosis. Results from this research were presented at the XXVI European Congress of Perinatal Medicine in September 2018.

Pneumothorax and Pneumatocoele Formation in a Patient with COVID-19: a Case Report

Coronavirus disease 2019 (COVID-19) causes significant morbidity and mortality for a proportion of infected patients, and our knowledge and understanding of its clinical, radiological and histopathological features are still evolving. An association between COVID-19 and pneumothorax has been described in an increasing number of case reports and series in the literature, which have largely focused on clinical and imaging features. We report the case of a patient who developed COVID-19 complicated by pneumothorax, requiring surgical intervention. We describe the histopathological features seen in the thorascopically resected bullectomy specimen—this is, to our knowledge, the first reported description of the morphological features of pneumothorax in this important clinical setting.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Rapid and complete paraffin removal from human tissue sections delivers enhanced Raman spectroscopic and histopathological analysis

Incomplete removal of paraffin and organic contaminants from tissues processed for diagnostic histology has been a profound barrier to the introduction of Raman spectroscopic techniques into clinical practice. We report a route to rapid and complete paraffin removal from a range of formalin-fixed paraffin embedded tissues using super mirror stainless steel slides. The method is equally effective on a range of human and animal tissues, performs equally well with archived and new samples and is compatible with standard pathology lab procedures. We describe a general enhancement of the Raman scatter and enhanced staining with antibodies used in immunohistochemistry for clinical diagnosis. We conclude that these novel slide substrates have the power to improve diagnosis through anatomical pathology by facilitating the simultaneous combination of improved, more sensitive immunohistochemical staining and simplified, more reliable Raman spectroscopic imaging, analysis and signal processing.

Global trends in incidence and mortality of neonatal encephalopathy due to birth asphyxia and trauma

Background

Neonatal encephalopathy due to birth asphyxia and trauma is a leading cause of premature death and long-term disability as estimated by the Global Burden of Disease (GBD) 2017 study. To evaluate comparative improvements in prevention and survival, this analysis evaluated GBD 2017 mortality to incidence (MI) ratios as a proxy for case fatality over time, location, and socio-demographic status.

Methods

We derived estimates of cause-specific mortality and incidence at birth from GBD 2017, calculating MI ratios of neonatal encephalopathy in children &lt;1 year. We analyzed temporal, geographic, and socio-demographic trends in incidence, mortality, and MI ratio.

Results

Neonatal encephalopathy incidence shows little change over time, with global incidence in children under one essentially the same in 2017 (1,996 cases per 100,000 (1,334-2,912)) and 1990 (1,996 cases per 100,000 (1,331-2,926)). Regions show the same trend, though a large difference exists between the highest and lowest regional incidence, with incidence in Central Sub-Saharan Africa over 20 times higher than in Australasia. Over the same period, MI ratios for neonatal encephalopathy have decreased across all regions. Model input data represented 52 countries for prevalence and 145 countries for mortality, with notable data sparsity in Africa and Eastern Europe.

Conclusions

Case fatality of neonatal encephalopathy, as approximated by MI ratio, has declined worldwide over the past three decades, but incidence has shown little change. This suggests treatment of neonatal encephalopathy has improved, but more research is needed on risk factors in order to increase prevention. Continued work is also needed to reduce disparities in incidence and mortality between countries with different levels of SDI. Improving data coverage in lower SDI regions will be critical to accurately monitor progress toward reducing inequity.

Key messages

Neonatal encephalopathy is a leading cause of premature death and disability. Incidence of neonatal encephalopathy has changed little since 1990, indicating more work is needed on prevention. Case fatality of neonatal encephalopathy can be approximated by the mortality to incidence ratio, and has declined worldwide over the past three decades, suggesting improvements in treatment.

P3545Association between diastolic dysfunction and two-year survival in heart failure patients with mid-range or reduced left ventricular ejection fraction

Background

Extensive studies have demonstrated prognostic impact of echocardiographic defined diastolic dysfunction (DD) in patients with preserved as well as reduced left ventricular ejection fraction (LVEF). Nevertheless, it remains controversial whether evaluation of DD could provide additional prognostic information in heart failure (HF) patients with impaired systolic function. The purpose of present study, therefore, is to investigate the prognostic impact of echocardiography-defined DD on survival in HF patients hospitalized in our centre from 2009 to 2017 with mid-range LVEF (HFmrEF, LVEF 41–49%) and reduced LVEF (HFrEF, LVEF<40%).

Methods

A total of 2018 patients with echocardiography-evidenced LVEF<50% and hospitalized in our centre between July 2009 to December 2017 were included. Baseline demographic and clinical data were obtained by reviewing the medical records. All patients subsequently completed a median clinical follow-up of 24 (IQR 13–36) months by medical record review or telephone interview. The primary endpoint was all-cause mortality or heart transplantation (HTx). Patients were divided into mild, moderate and severe DD according to recent guidelines.

Results

The mean age was 69±13 years in the HFmrEF group and 68±13 years in the HFrEF group. All-cause mortality/HTx rate was significantly higher in the HFrEF (all-cause death n=318 and HTx n=11, 30.9%) group than in patients with HFmrEF (all-cause death n=235 and HTx n=2, 24.9%, P=0.003). All-cause mortality/HTx rate increased in proportion to DD severity in HFmrEF patients: 17.1% (54/315) in the mild DD group, 25.4% (115/452) in the moderate DD group, and 37.0% (68/184) in the severe DD group (P<0.001) and in HFrEF patients: 18.9% (43/228) in the mild DD group, 30.3% (146/482) in the moderate DD group, and 39.2% (140/357) in the severe DD group (P<0.001). Multivariable Cox regression analysis showed that Doppler parameter early-diastolic mitral inflow velocity to septal mitral annular velocity ratio (E/E') >14 (HR 1.41, 95% CI 1.06–1.89, P=0.020) and peak tricuspid regurgitation velocity (TRVmax) >2.8m/s (HR 1.75, 95% CI 1.33–2.29, P<0.001) were independent determinants of all-cause mortality/HTx in patients with HFmrEF; while E/E'>14 (HR 1.48, 95% CI 1.08–2.04, P=0.015) remained as an independent determinant of all-cause mortality/HTx in patients with HFrEF after adjustment for clinical and other echocardiographic confounders. Besides DD-related parameters, after adjustment with age and sex, lower tricuspid and mitral annular plane systolic excursions (TAPSE and MAPSE) were also closely related to higher mortality/HTx rate in both HFmrEF and HFrEF patients.

Figure 1. Kaplan-Meier curves

Conclusion

Our results indicate that all-cause mortality/HTx rate increases in proportion to DD severity in both HFmrEF and HFrEF patients.

Constraints on Primordial Gravitational Waves Using Planck, WMAP, and New BICEP2/Keck Observations through the 2015 Season

We present results from an analysis of all data taken by the bicep2/Keck CMB polarization experiments up to and including the 2015 observing season. This includes the first Keck Array observations at 220 GHz and additional observations at 95 and 150 GHz. The Q and U maps reach depths of 5.2, 2.9, and 26  μK_{CMB} arcmin at 95, 150, and 220 GHz, respectively, over an effective area of ≈400 square degrees. The 220 GHz maps achieve a signal to noise on polarized dust emission approximately equal to that of Planck at 353 GHz. We take auto and cross spectra between these maps and publicly available WMAP and Planck maps at frequencies from 23 to 353 GHz. We evaluate the joint likelihood of the spectra versus a multicomponent model of lensed-ΛCDM+r+dust+synchrotron+noise. The foreground model has seven parameters, and we impose priors on some of these using external information from Planck and WMAP derived from larger regions of sky. The model is shown to be an adequate description of the data at the current noise levels. The likelihood analysis yields the constraint r_{0.05}<0.07 at 95% confidence, which tightens to r_{0.05}<0.06 in conjunction with Planck temperature measurements and other data. The lensing signal is detected at 8.8σ significance. Running a maximum likelihood search on simulations we obtain unbiased results and find that σ(r)=0.020. These are the strongest constraints to date on primordial gravitational waves.

Transcatheter mitral valve intervention: an emerging treatment for mitral regurgitation

Mitral regurgitation (MR) is a valvular heart disease associated with significant morbidity and mortality. Transcatheter mitral valve intervention (TMVI) repairs or replaces the mitral valve through small arterial and venous entry sites and so avoids risks associated with open heart surgery. Transcatheter devices targeting components of the mitral apparatus are being developed to repair or replace it. Numerous challenges remain including developing more adaptable devices and correction of multiple components of the mitral annulus to attain durable results. The mitral valve apparatus is a complex structure and understanding of the mechanisms of MR is essential in the development of TMVI. There will likely be a complementary role between surgery and TMVI in the near future.

A web-based prediction score for head and neck cancer referrals

OBJECTIVE

Following the announcement of the NHS Cancer Plan in 2000, anyone suspected of having cancer has to be seen by a specialist within 2 weeks of referral. Since this introduction, studies have shown that only 6.3%-14.6% of 2-week referrals were diagnosed with a head and neck cancer and that majority of the cancer diagnoses were via other referral routes. These studies suggest that the referral scheme is not currently cost-effective. Our aim is to develop a scoring system that determines the risk of head and neck cancer in a patient, which can then be used to aid GP referrals.

DESIGN

Retrospective data were collected from 1075 patients with 2-week head and neck cancer referrals from general practitioners. The retrospective data collected included patients' demographics, risk factors and relevant investigations. The data were used as input into a logistic regression to arrive at our model. Our approach included data analysis, machine learning techniques, statistical inference and model validation metrics to arrive at the best performing model. The model was then tested with more data from 235 prospective patients.

RESULTS

Using our results from the logistic regression, we created a web-based tool that GPs can use to calculate their patient's probability of cancer and use this result to assist in their decision regarding referral. Our prototype can be seen in Figure 2.

CONCLUSION

We have created a prototype scoring system that can be hosted online to assist GPs with their referrals with a sensitivity of 31% and specificity of 92%. While we acknowledge that there are several limitations to our model, we believe we have created a novel preliminary scoring system that has the potential to be improved dramatically with further data and be very helpful for GPs in a long run.

Multi-centre Raman spectral mapping of oesophageal cancer tissues: a study to assess system transferability

The potential for Raman spectroscopy to provide early and improved diagnosis on a wide range of tissue and biopsy samples in situ is well documented. The standard histopathology diagnostic methods of reviewing H&E and/or immunohistochemical (IHC) stained tissue sections provides valuable clinical information, but requires both logistics (review, analysis and interpretation by an expert) and costly processing and reagents. Vibrational spectroscopy offers a complimentary diagnostic tool providing specific and multiplexed information relating to molecular structure and composition, but is not yet used to a significant extent in a clinical setting. One of the challenges for clinical implementation is that each Raman spectrometer system will have different characteristics and therefore spectra are not readily compatible between systems. This is essential for clinical implementation where classification models are used to compare measured biochemical or tissue spectra against a library training dataset. In this study, we demonstrate the development and validation of a classification model to discriminate between adenocarcinoma (AC) and non-cancerous intraepithelial metaplasia (IM) oesophageal tissue samples, measured on three different Raman instruments across three different locations. Spectra were corrected using system transfer spectral correction algorithms including wavenumber shift (offset) correction, instrument response correction and baseline removal. The results from this study indicate that the combined correction methods do minimize the instrument and sample quality variations within and between the instrument sites. However, more tissue samples of varying pathology states and greater tissue area coverage (per sample) are needed to properly assess the ability of Raman spectroscopy and system transferability algorithms over multiple instrument sites.

Observational evidence of a long-term increase in precipitation due to urbanization effects and its implications for sustainable urban living

Although projected precipitation increases in East Asia due to future climate change have aroused concern, less attention has been paid by the scientific community and public to the potential long-term increase in precipitation due to rapid urbanization. A ten-year precipitation dataset was analysed for both a rapidly urbanized megacity and nearby suburban/rural stations in southern China. Rapid urbanization in the megacity was evident from satellite observations. A statistically significant, long-term, increasing trend of precipitation existed only at the megacity station (45.6mm per decade) and not at the other stations. The increase was attributed to thermal and dynamical modifications of the tropospheric boundary layer related to urbanization, which was confirmed by the results of our WRF-SLUCM simulations. The results also suggested that a long-term regional increase in precipitation, caused by greenhouse gas-induced climate change, for instance, was not evident within the study period. The urbanization-induced increase was found to be higher than the precipitation increase (18.3mm per decade) expected from future climate change. The direct climate impacts due to rapid urbanization is highlighted with strong implications for urban sustainable development and the planning of effective adaptation strategies for issues such as coastal defenses, mosquito-borne disease spread and heat stress mortality.