Predictors and Outcomes for COVID-19 Re-Admissions in the Anticipate Cohort.

Aims To describe readmissions of hospitalised patients with COVID-19, define predictors of readmission and explore the long term outcomes using the SF-12 score compared to patients who were not readmitted and those not hospitalised. Methods A single centre retrospective in North Inner-City Dublin. Recruitment was done through a COVID follow up clinic. Predictors of readmission and SF-12 scores at two timepoints post follow up at median 3 months and 12 months. Results Seventy (45%) participants were admitted, with a median age of 49.5 years (IQR 41.3-56.9), 36(51%) of whom were female. Unscheduled readmissions at ≤30 days in COVID-19 patients were 9(12.9%) and length of stay was four days (IQR 2-5). Readmissions were due to ongoing symptoms(n=9(64.3%)) or new complications(n=5(35.7%)). Mechanical ventilation and having symptoms of nausea and vomiting on index admission were predictive of readmission. (p=0.002). SF-12 scores at one year of readmitted patients were not different to patients who were never admitted at median one year follow up, p=.089. Conclusions Most readmissions were of short duration. Early follow up of patients post MV or who had nausea and vomiting on index admission should be prioritised. Wellbeing of readmitted patients was not different to those never hospitalised, at one year.

Electron and Ion Heating Characteristics during Magnetic Reconnection in the MAST Spherical Tokamak.

Electron and ion heating characteristics during merging reconnection start-up on the MAST spherical tokamak have been revealed in detail using a 130 channel yttrium aluminum garnet (YAG) and a 300 channel Ruby-Thomson scattering system and a new 32 chord ion Doppler tomography diagnostic. Detailed 2D profile measurements of electron and ion temperature together with electron density have been achieved for the first time and it is found that electron temperature forms a highly localized hot spot at the X point and ion temperature globally increases downstream. For the push merging experiment when the guide field is more than 3 times the reconnecting field, a thick layer of a closed flux surface form by the reconnected field sustains the temperature profile for longer than the electron and ion energy relaxation time ~4-10 ms, both characteristic profiles finally forming a triple peak structure at the X point and downstream. An increase in the toroidal guide field results in a more peaked electron temperature profile at the X point, and also produces higher ion temperatures at this point, but the ion temperature profile in the downstream region is unaffected.

Design of a real-time two-color interferometer for MAST Upgrade.

A single chord two-color CO2/HeNe (10.6/0.633 µm) heterodyne laser interferometer has been designed to measure the line integral electron density along the mid-plane of the MAST Upgrade tokamak, with a typical error of 1 × 10(18) m(-3) (∼2° phase error) at 4 MHz temporal resolution. To ensure this diagnostic system can be restored from any failures without stopping MAST Upgrade operations, it has been located outside of the machine area. The final design and initial testing of this system, including details of the optics, vibration isolation, and a novel phase detection scheme are discussed in this paper.

A field programmable gate array unit for the diagnosis and control of neoclassical tearing modes on MAST.

A real-time system has been developed to trigger both the MAST Thomson scattering (TS) system and the plasma control system on the phase and amplitude of neoclassical tearing modes (NTMs), extending the capabilities of the original system. This triggering system determines the phase and amplitude of a given NTM using magnetic coils at different toroidal locations. Real-time processing of the raw magnetic data occurs on a low cost field programmable gate array (FPGA) based unit which permits triggering of the TS lasers on specific amplitudes and phases of NTM evolution. The MAST plasma control system can receive a separate trigger from the FPGA unit that initiates a vertical shift of the MAST magnetic axis. Such shifts have fully removed m∕n = 2∕1 NTMs instabilities on a number of MAST discharges.

Deconvolution of Thomson scattering temperature profiles.

Deconvolution of Thomson scattering (TS) profiles is required when the gradient length of the electron temperature (T(e)) or density (n(e)) are comparable to the instrument function length (Δ(R)). The most correct method for deconvolution to obtain underlying T(e) and n(e) profiles is by consideration of scattered signals. However, deconvolution at the scattered signal level is complex since it requires knowledge of all spectral and absolute calibration data. In this paper a simple technique is presented where only knowledge of the instrument function I(r) and the measured profiles, T(e, observed)(r) and n(e, observed)(r), are required to obtain underlying T(e)(r) and n(e)(r). This method is appropriate for most TS systems and is particularly important where high spatial sampling is obtained relative to Δ(R).

A 130 point Nd:YAG Thomson scattering diagnostic on MAST.

A Thomson scattering diagnostic designed to measure both edge and core physics has been implemented on MAST. The system uses eight Nd:YAG lasers, each with a repetition rate of 30 Hz. The relative and absolute timing of the lasers may be set arbitrarily to produce fast bursts of measurements to suit the time evolution of the physics being studied. The scattered light is collected at F/6 by a 100 kg six element lens system with an aperture stop of 290 mm. The collected light is then transferred to 130 polychromators by 130 independent fiber bundles. The data acquisition and processing are based on a distributed computer system of dual core processors embedded in 26 chassis. Each chassis is standalone and performs data acquisition and processing for five polychromators. This system allows data to be available quickly after the MAST shot and has potential for real-time operations.

Absolute calibration of LIDAR Thomson scattering systems by rotational Raman scattering.

Absolute calibration of LIDAR Thomson scattering systems on large fusion devices may be achieved using rotational Raman scattering. The choice of calibrating gas molecule presents different options and design trade-offs and is likely to be strongly dependent on the laser wavelength selected. Raman scattering of hydrogenic molecules produces a very broad spectrum, however, with far fewer scattered photons than scattering from nitrogen or oxygen at the same gas pressure. Lower laser wavelengths have the advantage that the Raman cross section increases, sigma(Raman) proportional to 1/lambda(0)(4), but the disadvantage that the spectral width of the scattered spectrum decreases, Deltalambda(Raman) proportional to lambda(0)(2). This narrower spectrum makes measurement closer to the laser wavelength necessary. The design of the calibration technique presents a number of challenges. Some of these challenges are generic to all Thomson scattering systems. These include detecting a sufficient number of photoelectrons and designing filters that measure close to the laser wavelength while simultaneously achieving adequate blocking of the laser wavelength. An issue specific to LIDAR systems arises since the collection optics operates over a wide range of depth of field. This wide depth of field has the effect of changing the angle of light incident on the optical interference filter with plasma major radius. The angular distribution then determines the effective spectral transmission function of the interference filter and hence impacts on the accuracy of the absolute calibration. One method that can be used to increase absolute calibration accuracy is collecting both Stokes and anti-Stokes lines with optical filter transmission bands specifically designed to reduce systematic uncertainty.

Design and implementation of a full profile sub-cm ruby laser based Thomson scattering system for MAST.

A major upgrade to the ruby Thomson scattering (TS) system has been designed and implemented on the Mega-ampere spherical tokamak (MAST). MAST is equipped with two TS systems, a Nd:YAG laser system and a ruby laser system. Apart from common collection optics each system provides independent measurements of the electron temperature and density profile. This paper focuses on the recent upgrades to the ruby TS system. The upgraded ruby TS system measures 512 points across the major radius of the MAST vessel. The ruby laser can deliver one 10 J 40 ns pulse at 1 Hz or two 5 J pulses separated by 100-800 µs. The Thomson scattered light is collected at F/15 over 1.4 m. This system can resolve small (7 mm) structures at 200 points in both the electron temperature and density channels at high optical contrast; ∼50% modulated transfer function. The system is fully automated for each MAST discharge and requires little adjustment. The estimated measurement error for a 7 mm radial point is <4% of T(e) and <3% of n(e) in the range of 40 eV to 2 keV, for a density of n(e)=2×10(19) m(-3). The photon statistics at lower density can be increased by binning in the radial direction as desired. A new intensified CCD camera design allows the ruby TS system to take two snapshots separated with a minimum time of 230 µs. This is exploited to measure two density and temperature profiles or to measure the plasma background light.

Patient compliance with colposcopy information leaflets.

OBJECTIVE: To investigate patient satisfaction and compliance with recommendations in information leaflets sent to women prior to colposcopy clinic attendance and to establish whether alteration to the leaflet improved compliance. STUDY DESIGN: Data was collected prospectively and analysed retrospectively on the first 50 women attending for colposcopy before and after alterations to the information leaflet. RESULTS: All the patients received our patient leaflet and over 90% in each group felt that the information was understandable, clear and adequate. This is in complete contrast to overall compliance of less than 40% in both groups of the women. The first language of the patients did not make any major impact on compliance. CONCLUSION: Patients understanding of the information provided in the leaflets was not reflected in compliance. Compliance was no better in repeat attendees. The compliance with the information provided was not affected by the womens first language. Alterations in the leaflet did not improve compliance. Other methods of information provision should be looked at to try to improve compliance.

Total laparoscopic hysterectomy in morbidly obese women with endometrial cancer anaesthetic and surgical complications.

OBJECTIVE: To assess the feasibility, associated anaesthetic and surgical morbidity in all morbidly obese women with endometrial cancer treated with total laparoscopic hysterectomy bilateral salpingo-oophorectomy (TLHBSO). STUDY DESIGN: Data was collected prospectively and analysed retrospectively on all morbidly obese women who had TLHBSO between February 2003 and January 2007. RESULTS: One case was converted to laparotomy. The mean postoperative stay was 4.04 (3-7) days. The only postoperative surgical complication was an incisional port site hernia. Comorbidities were present in 76% (26/34) of women, 29% (10/34) had a single comorbid condition, and 26% (9/34) had two. A further 21% (7/34) had more than two. There were no major anaesthetic complications. Patients with a BMI > 50 required ventilation with high airway pressure despite using ventilatory strategies to keep them to a minimum. CONCLUSION: TLHBSO in the obese population is safe in the hands of experienced surgeons and anaesthetists. The safety of a total laparoscopic approach in the surgical management of uterine cancer remains to be demonstrated in prospective randomised trials.

Primary malignant melanoma arising in an ovarian cystic teratoma.

Cystic ovarian teratomas are common tumours. Malignant melanoma developing in a teratoma, however, is an extremely rare diagnosis. A 49-year-old woman with a history of weight loss and abdominal distension was referred to UCLH. She underwent laparotomy and bilateral salpingo-oophorectomy for a large right ovarian tumour. Histopathology revealed a malignant melanoma and carcinoid tumour in the right ovarian teratoma and an endometrioid adenocarcinoma in the left ovary. Subsequent vaginal hysterectomy revealed complex atypical hyperplasia in the endometrium. An extraovarian primary maelanoma could not be found. At this time the patient remains alive and well with no indication of recurrence.

Design of a new Nd:YAG Thomson scattering system for MAST.

A new infrared Thomson scattering system has been designed for the MAST tokamak. The system will measure at 120 spatial points with approximately 10 mm resolution across the plasma. Eight 30 Hz 1.6 J Nd:YAG lasers will be combined to produce a sampling rate of 240 Hz. The lasers will follow separate parallel beam paths to the MAST vessel. Scattered light will be collected at approximately f/6 over scattering angles ranging from 80 degrees to 120 degrees. The laser energy and lens size, relative to an existing 1.2 J f/12 system, greatly increases the number of scattered photons collected per unit length of laser beam. This is the third generation of this polychromator to be built and a number of modifications have been made to facilitate mass production and to improve performance. Detected scattered signals will be digitized at a rate of 1 GS/s by 8 bit analog to digital converters (ADCs.) Data may be read out from the ADCs between laser pulses to allow for real-time analysis.

Using adaptive tests for the analysis of repeated measurements.

Several methods have been proposed for the analysis of data obtained from experimental units that are observed at multiple time points. In this paper we evaluate the performance of an adaptive test for the interaction of group and time, and an adaptive test for the group effect with data sets having measurements at common time points on two groups of experimental units. The results from extensive simulation studies show that the adaptive tests maintain their level of significance and are often more powerful than the corresponding likelihood ratio and mixed model tests when the error distributions and the random effect distributions are nonnormal. When the distributions are normal, the adaptive tests are nearly as powerful as the other tests.

Cardiac troponin I and N-terminal pro-brain natriuretic peptide in umbilical artery blood in relation to fetal heart rate abnormalities during labor.

The use of continuous fetal heart rate (FHR) recordings to monitor fetal well-being during labor is standard clinical practice in developed countries. Little is known about the relationship, if any, that exists between these FHR abnormalities and the fetal cardiac musculature and function. The aim of this study was to investigate umbilical artery serum levels of cardiac troponin I, a sensitive and specific marker of myocardial necrosis, and N-terminal pro-brain natriuretic peptide (pro-BNP), a sensitive marker of left ventricular dysfunction, in relation to FHR abnormalities. Umbilical artery blood samples were taken from 27 cases immediately after delivery of the infant. There was evidence of significant FHR abnormalities in 11 of these cases (group 2) and the FHR recording was normal in 16 cases (group 1). The mean N-terminal pro-BNP level in umbilical artery serum in group 2 was 413 fmol/L (SEM = 85) and in group 1 was 223 fmol/L (SEM = 28)(p = 0.022). There was no significant difference observed in cardiac troponin I levels between the two groups. Umbilical artery serum N-terminal pro-BNP is elevated in association with fetal heart rate abnormality in the late stage of labor. This finding suggests that some degree of cardiac compromise accompanies FHR abnormality.

Cardiac troponin I in pre-eclampsia and gestational hypertension.

OBJECTIVE: To investigate serum cardiac troponin I, a sensitive marker of cardiac myocyte damage, in normal pregnancy and pregnancies complicated by hypertension with and without significant proteinuria. DESIGN: Prospective cross sectional study. SETTING: University hospital delivery suite. SAMPLE: Serum samples obtained from women in normal pregnancy and in pregnancies complicated by hypertension with and without significant proteinuria. METHOD: Women with hypertension in pregnancy (at least two readings of systolic blood pressure > 140 mmHg and diastolic blood pressure > 90 mmHg) (n = 26) and normotensive women (n = 43) were included in the study. Serum cardiac troponin I was measured using Beckman Access immunoassay. MAIN OUTCOME MEASURE: Serum cardiac troponin I level in the pregnancies complicated by hypertension (with and without significant proteinuria) compared with the levels measured in normotensive women. RESULTS: The median serum cardiac troponin I level in pregnancies complicated by hypertension was 0.118 ng/mL (n = 26) which was significantly greater than that measured in samples obtained from normotensive women in pregnancy (0.03 ng/mL; n = 43) (P < 0.0001). There were higher median serum cardiac troponin I levels in hypertensive women with significant proteinuria (0.155 ng/mL; n = 6), compared with those without proteinuria (0.089 ng/mL; n = 20; P = 0.03). CONCLUSION: Serum cardiac troponin I is elevated in women with hypertensive disorders of pregnancy indicating some degree of cardiac myofibrillary damage in these disorders.

Microsatellite instability in sporadic colorectal carcinoma is not an indicator of prognosis.

Fifty sporadic colorectal carcinomas diagnosed in 1991 were analysed for microsatellite instability at four loci. Five of 50 (10 per cent) tumours showed replication errors (RERs) at two or more loci and were classed as RER-positive (RER+). A further five showed RERs at one locus only. A significant association (Fisher exact test) was found between RER+ tumours and location in the proximal colon, exophytic shape, size >5 cm, histological margin, lymphoid reaction, and near-diploid DNA content. There was no significant difference for age, sex, grade, mucin production, p53 protein overexpression or Duke's stage. There was no significant difference in survival as measured over a 60-month follow-up period. The findings, though limited by the small case numbers involved, show an association between RER positivity in sporadic colorectal tumours and certain clinico-pathological features. They do not suggest a better clinical outcome for sporadic RER+ tumours.

Activated protein C resistance, thrombophilia, and inflammatory bowel disease.

Thromboembolic events frequently complicate the clinical course of patients with inflammatory bowel disease (IBD). Hereditary thrombophilia may contribute to this tendency. Resistance to activated protein C is the most recently described thrombophilic state and may account for up to 40% of patients with thrombophilia. Thirty-seven patients with IBD were studied (mean age 44 years, range 18-82 years). Three patients had a history of thrombotic episodes. The 37 controls included 23 men and 17 women (mean age 48 years, range 16-89 years). Disease activity was assessed using the Harvey Bradshaw index for patients with Crohn's disease and the Truelove and Witts grading system for patients with ulcerative colitis. Levels of fibrinogen, antithrombin III (ATIII), protein C, protein S, activated protein C resistance (APCR), and the presence of a lupus anticoagulant (LA) were determined. Median ATIII levels in patients with IBD were significantly lower than controls (98% vs 106%, P = 0.007), while fibrinogen was elevated (4.2 vs 3.3 g/liter, P = 0.026) despite quiescent disease activity. LA was detected in 7/37 patients in the IBD group compared to 0/37 controls. (chi2 = 5.68, P = 0.017). No significant difference was observed in levels of inherited thrombophilic factors and in particular APCR between IBD patients and controls. In conclusion, the presence of inherited thrombophilic defects, in particular APCR, is uncommon in patients with IBD and does not merit routine screening.

Nitrofurantoin-induced hepatotoxicity mediated by CD8+ T cells.

Nitrofurantoin is a synthetic nitrofuran commonly used for the treatment and prophylaxis of urinary tract infections. We describe the case of a 75-yr-old woman who was taking nitrofurantoin as prophylaxis against recurrent urinary tract infections, and who subsequently developed pulmonary and hepatic toxicity. We postulate that a breakdown product of the drug or the drug itself complexed to an endogenous peptide is presented by the class I HLA antigen on the hepatocyte cell membrane, inducing cytotoxic T cell activation and subsequently, hepatocyte death.