Real-world deployment of lateral flow SARS-CoV-2 antigen detection in the emergency department to provide rapid, accurate and safe diagnosis of COVID-19

BACKGROUND

Point-of-care (POC) SARS-CoV-2 lateral-flow antigen detection (LFD) testing in the emergency department (ED) could inform rapid infection control decisions but requirements for safe deployment have not been fully defined.

METHODS

Review of LFD test results, laboratory and POC-RT-PCR results and ED-performance metrics during a two-week high SARS-CoV-2 prevalence period followed by several months of falling prevalence.

AIM

Determine whether LFD testing can be safely deployed in ED to provide an effective universal SARS-CoV-2 testing capability.

FINDINGS

93% (345/371) of COVID-19 patients left ED with a virological diagnosis during the 2-week universal LFD evaluation period compared to 77% with targeted POC-RT-PCR deployment alone, on background of approximately one-third having an NHS Track and Trace RT-PCR test-result at presentation. LFD sensitivity and specificity was 70.7% and 99.1% respectively providing a PPV of 97.7% and NPV of 86.4% with disease prevalence of 34.7%. ED discharge-delays (breaches) attributable to COVID-19 fell to 33/3532 (0.94%) compared with the preceding POC-RT-PCR period (107/4114 (2.6%); p=<0.0001). Importantly, LFD testing identified 1 or 2 clinically-unsuspected COVID-19 patients/day. Three clinically-confirmed LFD false positive patients were appropriately triaged based on LFD action-card flowchart, and only 5 of 95 false-negative LFD results were inappropriately admitted to non-COVID-19 areas where no onward-transmission was identified. LFD testing was restricted to asymptomatic patients when disease prevalence fell below 5% and detected 1-3 cases/week.

CONCLUSION

Universal SARS-CoV-2 LFD testing can be safely and effectively deployed in ED alongside POC-RT-PCR testing during periods of high and low disease prevalence.

The social invisibility of mental health: understanding social exclusion through place & space

Background

The European target that the 5% of the healthcare service budget goes to mental health might not be enough to cover the inequity between health and mental health provision. The project is a multi-disciplinary, research-through-arts project, involving a Faculty of the Built Environment, a Division of Psychiatry and a School of Art. The project aims to identify elements demonstrating inequality demonstrated from place and space related to the facility provision.

Methods

The research compares mental vs healthcare facilities inside a catchment area, with photographs of the facades of the buildings and mapping their proximity to public transportation. It juxtaposes mental/healthcare facilities for access, condition and status compared to their surroundings.

Results

A book and an exhibition close to Bentham’s auto-icon, the designer of Panopticon custodial facility, demonstrated inverse links between his Panopticon, and the invisibility that NIMBYism produces towards the mentally ill that resulted in their exclusion, within deprived, vandalized, under-funded, isolated from public transport facilities “in the community”.

Conclusions

The project identified factors that contribute to the isolation of mental health facilities in terms of both space and place, and set the basis for further research in future projects. It demonstrated visually the under-budgeting of mental health facilities and their stigmatization as expressed by the centrality of locations and their overall projected image. This outlined the path for integrated, transdisciplinary research in the future involving architecture, arts and psychiatry. The project increased the awareness of the general public on social injustice, stigma and mental health. It combats NIMBYism and supports the fairer allocation of resources and placement of health facilities, aiming to put pressure to stakeholders involved in the NHS decision. Actions have been taken by the Trust involved to change.

Key messages

Inequalities between building (facades and location) contribute to mental illness stigma: this is what the general public views daily. Architecture can be a powerful medium to support inclusion.

Nonlinear elastic wave tomography for the imaging of corrosion damage

This paper presents a nonlinear elastic wave tomography method, based on ultrasonic guided waves, for the image of nonlinear signatures in the dynamic response of a damaged isotropic structure. The proposed technique relies on a combination of high order statistics and a radial basis function approach. The bicoherence of ultrasonic waveforms originated by a harmonic excitation was used to characterise the second order nonlinear signature contained in the measured signals due to the presence of surface corrosion. Then, a radial basis function interpolation was employed to achieve an effective visualisation of the damage over the panel using only a limited number of receiver sensors. The robustness of the proposed nonlinear imaging method was experimentally demonstrated on a damaged 2024 aluminium panel, and the nonlinear source location was detected with a high level of accuracy, even with few receiving elements. Compared to five standard ultrasonic imaging methods, this nonlinear tomography technique does not require any baseline with the undamaged structure for the evaluation of the corrosion damage, nor a priori knowledge of the mechanical properties of the specimen.

The weight debate

Therapeutic interventions administered on Critical Care are often dosed on the basis of patient body size, to ensure treatments are effective in achieving their goals and to prevent harm from overdose. Many treatment modalities use predicted weights estimated from descriptors such as sex, weight and height to reduce error that is associated with using total body weight in critically ill patients. In this article we review the size descriptors that have been described, their origin and calculation. We then examine the role they play in dosing of common therapies utilised in Critical Care and potential areas of research for the future.

Thrombosis of the external jugular vein: a rare complication of a proximal humerus fracture treated with collar and cuff immobilisation

We report the case of an 87-year-old woman who developed a thrombosis of her external jugular vein after sustaining a proximal humerus fracture managed nonoperatively with a collar and cuff. At review in fracture clinic she was found to have an enlarged external jugular vein which was subsequently found to be thrombosed. Her collar and cuff had been applied very tightly and it was felt by the ENT team to be the cause of the thrombosis of her external jugular vein. She was fully anticoagulated with warfarin after subsequently developing a deep vein thrombosis in the subclavian and axillary veins. She made a full recovery following anticoagulation. In this case, we review the potential causes of this rare and underdiagnosed condition, as well as the usual investigations and treatments. We also review the common complications of this fracture and the alternative treatment options available.

Cumulus gene expression as a predictor of human oocyte fertilisation, embryo development and competence to establish a pregnancy

The close relationship between cumulus cell function and oocyte developmental competence indicates that analysis of cumulus gene expression is a potential non-invasive method to aid embryo selection and IVF outcome. Cumulus was isolated from 674 oocytes from 75 women undergoing ICSI and gene expression analysed by quantitative RT-PCR. Cumulus expression of cyclooxygenase 2 (PTGS2) was higher with mature oocytes, whereas brain-derived neurotrophic factor (BDNF) was lower when fertilisation was normal. Expression levels of gremlin (GREM1) and BDNF were weak positive and negative predictors of embryo quality respectively. Ranking of GREM1 expression within cohorts of oocytes showed that oocytes associated with the highest GREM1 expression were more likely to be transferred or cryopreserved than discarded (49 vs 33%, P<0.02), although the clinical pregnancy rate was not significantly different. This study demonstrates both the feasibility and difficulties of this method of analysis in the largest such group studied thus far. Novel relationships between BDNF expression and fertilisation were identified, and the potential value of GREM1 expression as a marker of embryo quality supports the further assessment of GREM1 analysis in the context of embryo selection.

Behavior of TiO2 thin film in a nanocapacitor

Gold and platinum nanocapacitors have been fabricated using a magnetron sputtering technique. TiO2 is used as a dielectric material to separate the metal layers which act as the parallel plates for the capacitors. The thickness for metal films and TiO2 layer is 80 nm and 400 nm, respectively. Capacitance of the nanocapacitors has been measured and dielectric constant of TiO2 calculated. Both capacitance and dielectric constant are observed to have strong frequency dependence.

Three hundred and thirty cycles of preimplantation genetic diagnosis for serious genetic disease: clinical considerations affecting outcome

OBJECTIVE

To report on our experience with preimplantation genetic diagnosis (PGD) cycles performed for serious genetic disease in relation to the clinical factors affecting outcome.

DESIGN

Retrospective review of data from a single centre.

SETTING

Tertiary referral PGD centre in a London teaching hospital.

METHODS

The PGD cycles included 172 cycles for chromosome rearrangements, 96 cycles for single-gene disorders and 62 cycles for X-linked disorders. In vitro fertilisation was the preferred method in chromosome rearrangement and X-linked cases, while intra cytoplasmic sperm injection was used in all single-gene disorders. Appropriate in situ hybridisation fluorescence probes were used in chromosome rearrangement and X-linked cases and polymerase chain reaction was used in single-gene disorders. All pregnancies were followed till delivery.

MAIN OUTCOME MEASURE

Live birth rate per PGD cycle started.

RESULTS

Eighty-six percent of cycles started (283) reached oocyte retrieval and 3743 eggs were collected, of which 2086 fertilised normally (55.7%). Two hundred and fifty cycles (76%) had embryos sutiable for biopsy on day 3 of in vitro culture, 1714 embryos were biopsied, and in 205 cycles (62%), there was at least one unaffected embryo available for transfer, resulting in 90 pregnancies, 68 clinical pregnancies and 58 live birth. The live birth rate was 18% per cycle started, 21% per egg retrieval and 28% per embryo transfer which significantly affected the live birth outcome. Woman age, number of eggs collected and achieving cryopreservation of surplus embryos had no statistically significant effect on treatment outcome.

CONCLUSIONS

The live birth outcome of PGD cycles for serious genetic disorder is modest and is affected by the number of embryos genetically suitable for transfer.

Breeding and longevity in captive Australian sea lions Neophoca cinerea at zoos and aquaria in Australia: 1965-2003

Australian sea lions (Neophoca cinerea) are known to have been kept in aquaria and zoos in Australia since 1965. During that time at least 41 births were recorded, of which 19 were in Adelaide, 15 at Adelaide Zoo and 4 at Marineland of South Australia. The mean interval between successive births in Adelaide was 538.9 � 9.5 days (18.0 months; n = 10) and the mean assumed pregnancy period, including embryonic diapause, was 536.0 � 11.4 days (17.9 months; n = 9). The mean interval between parturition and presumed successful mating was 8.4 � 1.6 days (n = 5). Births occurred in all months except January, June, August and December. Figures for New South Wales and Queensland establishments are too small and scattered over time for any pregnancy periods or birth intervals to be determined. Likewise, latitudinal differences, if any, were not evident, because of the paucity of data from these more northerly places. One female at the Adelaide Zoo produced 8 pups between 1986 and 1997; she is still alive after 22 years in captivity. The youngest known-age (captive-born) female was 4 years, 8 months old when she gave birth to her first pup; and the oldest female in captivity to give birth to a pup was aged approximately 21 years, 8 months. The longest recorded captive period for a female was more than 25 years by 31 December 2003, and for a male it was 21 years, 11 months. A captive-bred female was still alive after 18 years, 2 months, 24 days; another such female died aged 18 years, 2 months, 18 days. These life spans appear to be similar to those that meagre data suggest for tagged N. cinerea in the wild.

Phospholipase Cζ causes Ca2+ oscillations and parthenogenetic activation of human oocytes

At fertilization in mammals the sperm activates development of the oocyte by inducing a prolonged series of oscillations in the cytosolic free Ca2+concentration. One theory of signal transduction at fertilization suggests that the sperm cause the Ca2+oscillations by introducing a protein factor into the oocyte after gamete membrane fusion. We recently identified this sperm-specific protein as phospholipase Cζ (PLCζ), and we showed that PLCζ triggers Ca2+oscillations in unfertilized mouse oocytes. Here we report that microinjection of the complementary RNA for human PLCζ causes prolonged Ca2+oscillations in aged human oocytes that had failed to fertilize duringin vitrofertilization or intracytoplasmic sperm injection. The frequency of Ca2+oscillations was related to the concentration of complementary RNA injected. At low concentrations, PLCζ stimulated parthenogenetic activation of oocytes. These embryos underwent cleavage divisions and some formed blastocysts. These data show that PLCζ is a novel parthenogenetic stimulus for human oocytes and that it is unique in its ability to mimic the repetitive nature of the Ca2+stimulus provided by the sperm during human fertilization.

LPA1 receptor-deficient mice have phenotypic changes observed in psychiatric disease

Several psychiatric diseases, including schizophrenia, are thought to have a developmental aetiology, but to date no clear link has been made between psychiatric disease and a specific developmental process. LPA(1) is a G(i)-coupled seven transmembrane receptor with high affinity for lysophosphatidic acid. Although LPA(1) is expressed in several peripheral tissues, in the nervous system it shows relatively restricted temporal expression to neuroepithelia during CNS development and to myelinating glia in the adult. We report the detailed neurological and behavioural analysis of mice homozygous for a targeted deletion at the lpa(1) locus. Our observations reveal a marked deficit in prepulse inhibition, widespread changes in the levels and turnover of the neurotransmitter 5-HT, a brain region-specific alteration in levels of amino acids, and a craniofacial dysmorphism in these mice. We suggest that the loss of LPA(1) receptor generates defects resembling those found in psychiatric disease.

Initial management of ocular hypertension and primary open-angle glaucoma: an evaluation of the royal college of ophthalmologists' guidelines

PURPOSE

The purpose of this study was to identify any consensus of opinion among consultant ophthalmologists in Wales with respect to the initial management of glaucoma referrals based on the published guidelines of the Royal College of Ophthalmologists (RCO) and to compare consultant opinion with the practice in a typical hospital.

METHOD

The RCO guidelines document was studied to identify clear statements, which could be adopted as standards for audit purposes. A questionnaire was designed and sent to all consultant ophthalmologists in Wales (n=37) to obtain their opinions. An audit was performed of 100 consecutive patients referred to our unit as glaucoma suspects with regard to initial management. Descriptive statistical analysis was performed.

RESULTS

A good response rate for a postal questionnaire was obtained (81%) with 79.1% of responders finding the guidelines of at least some help. Levels of agreement with the definitions of ocular hypertension (OH) and primary open-angle glaucoma (POAG) were 76.7 and 86.7%, respectively. There was consensus of consultant opinion regarding many of the elements of the baseline clinical assessment with the significant exceptions of the necessity for dilated fundoscopy, gonioscopy, retinal nerve fibre layer assessment, and drawing of optic discs. The various 'clinical scenarios' for management of the RCO document were not all endorsed. The clinical audit results of the initial management of glaucoma referrals accurately reflected the consensus of the consultant opinion.

DISCUSSION

The RCO guidelines document represents a useful contribution to the management of patients with OH and POAG. Nevertheless, considerable variation in opinion exists concerning even the most basic areas. With the advent of clinical governance, bridging the gap between the conclusions of College working parties and realities of everyday practice will assume greater importance.

Neuropilin-2 is required in vivo for selective axon guidance responses to secreted semaphorins

Neuropilins are receptors for class 3 secreted semaphorins, most of which can function as potent repulsive axon guidance cues. We have generated mice with a targeted deletion in the neuropilin-2 (Npn-2) locus. Many Npn-2 mutant mice are viable into adulthood, allowing us to assess the role of Npn-2 in axon guidance events throughout neural development. Npn-2 is required for the organization and fasciculation of several cranial nerves and spinal nerves. In addition, several major fiber tracts in the brains of adult mutant mice are either severely disorganized or missing. Our results show that Npn-2 is a selective receptor for class 3 semaphorins in vivo and that Npn-1 and Npn-2 are required for development of an overlapping but distinct set of CNS and PNS projections.

Bilateral thalamic stimulation for the treatment of essential tremor

OBJECTIVE

To determine the safety and efficacy of bilateral thalamic stimulation in the treatment of essential tremor (ET).

METHODS

Nine ET patients with disabling tremor refractory to pharmacotherapy underwent bilateral staged implants. Tremor was assessed by the Fahn-Tolosa-Marin Tremor Rating Scale at baseline 1 (before first implant), baseline 2 (before second implant), and at 6-month and 1-year follow-up. Blinded evaluations were performed at 3 months. Associated changes in speech were evaluated in six patients. There were seven men and two women with a mean age of 73.8 years.

RESULTS

There was a significant improvement in the mean total tremor score from a baseline of 66.1+/-11.6 to 28.4+/-12.8 12 months after the second surgery. Similarly, the mean motor tremor subscore was 20.1+/-5.0 before the first surgery and improved significantly to 14.1+/-3.6 before the second surgery. Motor tremor scores 6 months after the second surgery (6.0+/-3.7) and 12 months after the second surgery (7.5+/-3.9) also improved significantly relative to the preoperative scores. The mean activities of daily living (ADL) subscore at baseline was 18.2+/-2.9 and improved significantly before the second surgery to 9.0+/-3.2. These ADL scores further improved 6 months (6.2+/-5.2) and 12 months (7.9+/-5.7) following the second surgery, but these gains were not significant. Blinded evaluations also revealed a similar degree of improvement. Complications were noted in five patients: asymptomatic intracranial hematoma (1), postoperative seizures (1), a hematoma over the implanted pulse generator (IPG) (1), lead repositioning (1), and IPG malfunction (1). Adverse effects related to stimulation were mild and resolved with adjustment of the stimulation parameters. Three of the six patients demonstrated worsening of dysarthria with both stimulators on.

CONCLUSIONS

Bilateral thalamic stimulation is effective in reducing tremor and functional disability in ET; however, dysarthria is a possible complication.

The relationship of attributional beliefs to self-esteem

Several studies have reported that beliefs about the causes of events (i.e., causal attributions) are related to achievement-oriented behavior. Skinner (1995) has suggested that achievement-oriented behavior is related to beliefs about successful strategies and beliefs about the capacity to enact those strategies. Based on Skinner's research, Wellborn, Connell, and Skinner (1989) developed the Students' Perception of Control Questionnaire (SPOCQ). In the present investigation, the SPOCQ was adapted for use with adolescents and adults. The SPOCQ and the Rosenberg Self-esteem Scale were administered to 147 college students. The internal consistency and the intercorrelations of the SPOCQ subscales were found to be acceptable. Additionally, SPOCQ scores were related to self-esteem and grade point average. There were statistically significant differences in the SPOCQ scores for males and females and in the relation of SPOCQ scores to self-esteem. It is suggested that the three constructs measured by the SPOCQ (control, strategies, and capacity) provide a more complete description of attributional beliefs than do previous scales.

Cost effectiveness of a single-function treatment center for cataract surgery

PURPOSE

To compare the clinical and cost effectiveness of two models for cataract treatment: a single-function Cataract Treatment Centre (CTC) and a general ophthalmology service.

SETTING

Cataract Treatment Centre and the general ophthalmology service at Sunderland Eye Infirmary, Sunderland, United Kingdom.

METHODS

Two hundred patients were studied using two models of care: 100 in the CTC and 100 in the general ophthalmology service. Outcome measures were best corrected visual at 3 months postoperatively or at discharge and occurrence of surgery-related complications. All direct costs to the National Health Service were identified, measure, and assessed.

RESULTS

Clinical outcomes in the two groups were similar. The average cost per patient was 496.90 pounds ($760.25) at the CTC and 566.34 pounds ($866.50) at the general ophthalmology service. The cost per patient treated as a day case in the general service group was 495.84 pounds ($758.63). Thus, treatment at the CTC was more cost effective than in the mixed service group and as cost effective as in the day case subgroup.

CONCLUSIONS

Depending on local circumstances, day care must be delivered more cost effectively in a single-function center than in a general ophthalmology service. We recommend day care using local anesthesia and protocols for assessment, surgery, and follow-up.

Extracapsular cataract surgery using capsulorhexis with viscoexpression via a limbal section

Two hundred consecutive patients had extracapsular cataract surgery by capsulorhexis and viscoexpression. Capsulorhexis, attempted in 195 eyes, was successful in 87.7%. Viscoexpression was attempted in 162 cases and successfully delivered the nucleus in 87.7%. There were five cases of zonule rupture, one of posterior capsule rupture, and two of vitreous loss. If the capsulorhexis is larger than 5 mm, viscoexpression can be safely used on all cataracts, regardless of nuclear density, and is the ideal transition to phacoemulsification.

Genetic diagnosis using polymerase chain reaction and fluorescent in-situ hybridization analysis of biopsied cells from both the cleavage and blastocyst stages of individual cultured human preimplantation embryos

Cultured human preimplantation embryos have been used to develop methods which allow preimplantation genetic diagnosis (PGD) analyses by polymerase chain reaction (PCR) and fluorescent in-situ hybridization (FISH) on biopsied blastomeres and trophectoderm cells from the same embryo. An experimental design is described and experiments undertaken, which demonstrate the feasibility of extending biopsy and PGD procedures currently in use. We have shown that dual-stage biopsies are possible, and that the PCR and FISH analyses of the biopsied cell samples are effective. One to two blastomeres were biopsied from an 8- to 10-cell embryo and processed for the simultaneous PCR amplification of a beta-globin and a cytosine adenine (CA) repeat sequence, or a Y chromosome sequence. FISH procedures were also used to detect the presence of Y chromosome markers. The biopsied cleavage-stage embryo can be cultured to the blastocyst stage, where the serial biopsy of three to five mural trophectoderm cells provides two further cell samples. These can be used to repeat and/or undertake additional PGD analyses. The biopsied blastocyst is either used to confirm earlier diagnoses, or placed in culture for a further 4-24 h. Maintenance of a blastocoele cavity, hatching and formation of an outgrowth demonstrates continuing viability following the dual-stage biopsy procedures. The PCR DNA amplification procedures are effective at the cellular level for both biopsied blastomeres and mural trophectoderm cells. The FISH techniques have shown a definitive Y signal in 50% (one out of two) and 100% (two out of two) of the biopsied blastomeres and 72% (two out of three, four out of five and 7 out of 10) for the trophectoderm cell nuclei. Preliminary experiments have demonstrated that the FISH preparations can be re-amplified to improve the signal, and dual fluorescent procedures using the X and Y probes are effective. A retrospective PCR analysis has also been undertaken on preparations of biopsied cells which were previously used for PGD analysis by FISH.

Parthenogenetic activation and development of fresh and aged human oocytes

OBJECTIVE

To develop a systematic study of the parthenogenetic activation and early development of human oocytes.

DESIGN

Human oocytes (both freshly retrieved and remaining unfertilized after exposure to spermatozoa) were exposed to alcohol or calcium ionophore and examined for evidence of activation.

SETTING

Academic research department of a teaching hospital.

PATIENTS, PARTICIPANTS

Couples donating oocytes were undergoing therapy for infertility with in vitro fertilization or gamete intrafallopian transfer.

INTERVENTIONS

Gonadotropin-releasing hormone agonist and human menopausal gonadotropin were administered at therapeutic doses.

MAIN OUTCOME MEASURES

After application of activation stimuli at varying doses and durations, oocytes were examined for evidence of meiotic reactivation, pronuclear formation, deoxyribonucleic acid content, and cleavage.

RESULTS

Fresh and aged human oocytes can be activated parthenogenetically using a calcium ionophore but at lower rates than seen for mouse oocytes (typically 50% to 60% versus 90% to 100%, respectively). Ethanol was a poor activating agent (maximum activation rate 16%). Human parthenotes can complete division to the eight cell stage.

CONCLUSIONS

These results indicate that parthenote embryos may provide a source of material to study changes that occur during early human development. The data also raise the possibility that some early human pregnancy losses may involve oocytes that have been parthenogenetically activated spontaneously.

Behaviour of spherical and irregular (U,Pu)O2 particles after inhalation or intratracheal instillation in rat lung and during in vitro culture with bovine alveolar macrophages

Spherical and irregularly shaped mixed (U,Pu) oxide particles were administered to rats by inhalation and by intratracheal instillation. The lung retention of the particles was independent of particle shape and of the route of administration. Only a small percentage of the administered radioactivity was found in other organs. Detailed electron microscopic studies showed particles within membrane-enclosed vacuoles as well as lying free in the cytoplasm.