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Polycylic Aromatic Hydrocarbons (PAHs) are produced during the incomplete burning of organic materials. PAH sources include vehicle exhaust, tobacco smoke and waste incineration. Environmental and occupational exposures to PAHs are known to occur. Cancer is a significant endpoint of PAH exposure and several occupations associated with high PAH exposure have been classified by IARC as carcinogenic to humans (Group 1). Pyrene is a common component of PAH mixtures and metabolism of pyrene leads to the excretion of 1-hydroxypyrene glucuronide (1-OHPyrG) in urine. Laboratory measurement of urinary 1-OHPyrG is employed in occupational and environmental biomonitoring programmes. The production of an anti-1-OHPyrG monoclonal antibody would allow the development of a PAH biomonitoring ELISA facilitating large scale laboratory screening and routine testing. The development of a lateral flow immunoassay and the production of a field test (point of use test) would greatly increase the value of biomonitoring. A novel Lateral Flow has been developed which employs an anti-1-OHPyrG sheep monoclonal antibody (Mab) to capture the PAH metabolite. The captured metabolite is visualised through a second Mab raised against the Mab-1-OHPyrG immune complex. This sandwich assay provides a positive correlation between the assay signal and biomarker concentration. A Smartphone camera allows signal measurement and a carefully considered 'app' provides result interpretation and data analysis. Results are provided in an exposed/not-exposed format. Performance of the lateral flow was confirmed through a comparative study and field trial. The development of a lateral flow test provides "real-time" analysis to occupational health professionals. On-site screening allows the immediate confirmation of safe working practice, provides immediate reassurance to those involved in potentially hazardous activities and greatly increases the efficacy of biomonitoring., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Lathan Ball reports financial support was provided by Bioventix plc. Lathan Ball reports a relationship with Bioventix plc that includes: consulting or advisory and travel reimbursement. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper, (Copyright © 2024 Elsevier B.V. All rights reserved.)

Mediastinal mass in pregnancy is a rare condition that presents significant anaesthetic challenges. We present a woman with relapsed Hodgkin's lymphoma during pregnancy who declined to have chemotherapy because of concerns for her unborn child. She failed to attend follow-up clinic appointments and presented at 33 weeks' gestation with tracheal deviation and narrowing down to the level of the carina, as a result of large neck and mediastinal masses. She required delivery of the baby to allow her to receive urgent chemotherapy. We describe successful management of a caesarean section under combined spinal-epidural anaesthesia, at which bilateral femoral vein access was gained in case of the need for urgent extracorporeal membrane oxygenation., (Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.)

The application of silver nanoparticles to electrochemical metalloimmunoassays has previously been reported (Szymanski et al., 2009) and is now used in the electrochemical Argento immunoassay platform via UK Patent No. 2458420. The development of an immunoassay in this format requires the optimisation of the antibody to silver nanoparticle conjugation process. Issues such as pH, antibody concentration and other factors can affect the assay performance. In order to determine the effect of these variables it is necessary to understand and control the effects of other factors that may affect the assay signal. In this study a number of conditions which affect the assay signal were identified and methods developed to minimise variability in the assay signal, resulting in a standardised method allowing easy comparisons of silver nanoparticle conjugates prepared and assayed at different times., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The aim of this study was to investigate facial expression recognition (FER) accuracy in social phobia and in particular to explore how facial expressions of emotion were misclassified. We hypothesised that compared with healthy controls, subjects with social phobia would be no less accurate in their identification of facial emotions (as reported in previous studies) but that they would misclassify facial expressions as expressing threatening emotions (anger, fear or disgust). Thirty individuals with social phobia and twenty-seven healthy controls completed a FER task which featured six basic emotions morphed using computer techniques between 0 percent (neutral) and 100 percent intensity (full emotion). Supporting our hypotheses we found no differences between the groups on measures of the accuracy of emotion recognition but that compared with healthy controls the social phobia group were more likely both to misclassify facial expressions as angry and to interpret neutral facial expressions as angry. The healthy control group were more likely to misclassify neutral expressions as sad. The importance of the role of these biases in social phobia needs further replication but may help in understanding the disorder and provide an interesting area for future research and therapy., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

It has been postulated that the supplementary motor area (SMA) is involved in the initiation of movement and in gating of afferent input to motor cortex (MI) from peripheral receptors. We studied the responses of 119 neurons in MI to imposed disturbances of wrist-movement performance generated by the introduction of torque pulses before, during and after localized cooling of the SMA in conscious monkeys. The cooling of SMA did not prevent monkeys from making these simple movements. Eighty-two neurons responded to the wrist perturbations. Only 7 of these neurons changed their responsiveness with unilateral or bilateral cooling of SMA. From the data we have obtained on MI neuronal firing patterns, the SMA does not appear to modulate the long-latency trans-cortical stretch reflex during the periods in a task that we have investigated. Nor does it prevent animals from performing these simple movements to a visual target.

At a time when both electrical and magnetic stimulation of the human brain are being used to assess cortical motor outflow in man, it is important to re-examine the organization of the motor areas of the cerebral cortex, the evidence which exists about the structures that are activated by epicortical stimulation, the nature of the projections from the cerebral cortex to lower motor centers, the physiological influences that are exerted on motoneurons and interneurons by these descending pathways and the relevance of all of these for the control of voluntary movement. This review examines the relationships of neuronal activities in some motor regions of the cerebral cortex to movement performance as revealed by recording of neuronal discharges during self-paced movements performed by conscious monkeys, and the relevance of these observations to the understanding of mechanisms of voluntary control of skilled movement performance in man. It documents detailed information about the precise connections made by descending cortico-motoneuronal fibers in the monkey and proposes a relationship between the analogous structural arrangements in man and the voluntary control of skilled movement. Comparison of some of the general propositions which derive from studies of cortico-motoneuronal commands in the monkey with the EMG results from magnetic stimulation in man leads to the suggestion that direct monosynaptic excitatory effects may be relevant to the control of both proximal and distal muscles in man. Electrical recordings of the neuronal activities of individual cells in strategic cytoarchitectonic areas of the monkey's cerebral cortex also provide a neurophysiological correlate of observations on regional cerebral blood flow and regional metabolism as these are studied in human subjects performing movement tasks. Hence it is possible to explain the involvement of supplementary motor areas of both hemispheres in the organization of the time-ordered commands for manual tasks. A deficit in bimanual coordination is evident in monkeys with a unilateral lesion of the supplementary motor area and this deficit mimics the disorder of voluntary control of bimanual manipulation reported in man.

Single cell recordings were made from movement-related neurones from the precentral cortex of two monkeys, trained to perform a simple lever-pulling task. They were also trained to remain relaxed while the arm was explored with passive movements at different joints, cutaneous stimuli and during the application of two types of phasic muscle stretch: percutaneous vibration and percussion of muscle tendons. Recordings were made of the responses of cortical neurones both to the 'natural' stimuli and to vibration of specific muscle tendons or percussion of the triceps tendon. Both tendon percussion and vibration excited neurones within area 4 with an average latency for tendon percussion of 21.0 msec. There was a high degree of consistency in the effects on single neurones of tendon percussion and vibration at the same site. Although long-term facilitation was not seen. vibration-induced discharge in the motor cortex should be considered as a potential mechanism of its effects in intact man. In contrast to the similarity of the effect of the two forms of phasic stretch, the relationship between a single neurone's response to either tendon percussion or vibration and to passive movement was complex. The dissociation seen between the effects of phasic muscle stretch and that of passive movement may underlie the failure, in man, to find uniformly increased long-latency stretch reflexes in clinical states of extrapyramidal rigidity.

The influence of diet on aryl acid metabolism was determined in normal and azotemic subjects. Aryl acid content of serum and urine was estimated by fluorometry in relation to hippuric acid as a standard (FI-Hipp). Secretory activity, a reflection of the biological potency of aromatic acids in serum and urine, was determined by bioassay. The urinary excretion of FI-Hipp and secretory activity of five normal persons on an ad lib diet was 0.78 and 2.25 mM/day, respectively; similar values were observed in two subjects with chronic renal insufficiency. Subjects were fed prunes and cranberries, since these foods contain abundant quantities of hippurate precursors. Prunes 1.5 g/kg body weight, caused the urinary excretion of both FI-Hipp and secretory activity to increase about tenfold in normal and azotemic subjects. Prune feeding caused the serum levels of FI-Hipp and secretory activity to increase about threefold. Cranberries increased the renal excretion of FI-Hipp and secretory activity as did the ingestion of a beverage containing benzoate as a preservative. On the basis of these studies it is clear that diet is an important determinant of the load of aryl acids for urinary excretion; in patients with renal insufficiency the ingestion of foods containing precursors may cause serum level of biologically active aryl acids to increase strikingly.