Mental health and child refugees

This paper presents an overview of the importance of mental health services for unaccompanied asylum-seeking children in the United Kingdom. It reviews what mental health support appears to be available in the United Kingdom following an on-line search which took place in Spring 2021 and using information gathered through 22 interviews and focus groups with stakeholders. The latter group are defined as people working with asylum-seeking children. The primary stakeholders were local authority staff, although interviews were also conducted with local government associations (London Councils, the Local Government Association), NHS bodies and the voluntary sector. Often, further relevant stakeholders were identified during interviews. The report details the aims, methodology and context, before the findings are presented which is followed by recommendations for improving mental and social care provision for unaccompanied asylum-seeking children in the United Kingdom.

[Morphine poisoning in chronic kidney failure. Morphine-6-glucuronide as a pharmacologically active morphine metabolite]

HISTORY AND ADMISSION FINDINGS

A 57-year-old woman with metastasizing ovarian cancer and chronic renal failure was admitted for morphine treatment of an acute lumbospinal pain syndrome, ambulant treatment with analgesics having failed provide adequate pain relief. On admission due to pain the conscious patient presented with reduced general condition and lumbal pain sensitive to tapping. Lasègue's sign was positive on both sides, no other disturbed neurological functions were found.

TREATMENT AND COURSE

On the 7th day of morphine administration she became somnolent and breathing became markedly depressed, indicating overdosage, metabolic and intracranial causes having been excluded. Naloxone, an opioid antagonist, was given i.v. and the breathing pattern improved. But drowsiness continued for another 48 hours and only regressed after repeated doses of naloxone.

CONCLUSIONS

Morphine-6-glucuronide (M6G), formed from morphine in the liver, accumulates in blood and penetrates the blood-brain barrier, binding with strong affinity to opiate receptors and exerts a strong analgesic effect. As M6G is excreted by the kidney, its concentration rises in renal failure and can lead to severe intoxication. Morphine dosage must therefore be carefully controlled in patients with renal failure.

Predictive coding: a fresh view of inhibition in the retina

Interneurons exhibiting centre--surround antagonism within their receptive fields are commonly found in peripheral visual pathways. We propose that this organization enables the visual system to encode spatial detail in a manner that minimizes the deleterious effects of intrinsic noise, by exploiting the spatial correlation that exists within natural scenes. The antagonistic surround takes a weighted mean of the signals in neighbouring receptors to generate a statistical prediction of the signal at the centre. The predicted value is subtracted from the actual centre signal, thus minimizing the range of outputs transmitted by the centre. In this way the entire dynamic range of the interneuron can be devoted to encoding a small range of intensities, thus rendering fine detail detectable against intrinsic noise injected at later stages in processing. This predictive encoding scheme also reduces spatial redundancy, thereby enabling the array of interneurons to transmit a larger number of distinguishable images, taking into account the expected structure of the visual world. The profile of the required inhibitory field is derived from statistical estimation theory. This profile depends strongly upon the signal: noise ratio and weakly upon the extent of lateral spatial correlation. The receptive fields that are quantitatively predicted by the theory resemble those of X-type retinal ganglion cells and show that the inhibitory surround should become weaker and more diffuse at low intensities. The latter property is unequivocally demonstrated in the first-order interneurons of the fly's compound eye. The theory is extended to the time domain to account for the phasic responses of fly interneurons. These comparisons suggest that, in the early stages of processing, the visual system is concerned primarily with coding the visual image to protect against subsequent intrinsic noise, rather than with reconstructing the scene or extracting specific features from it. The treatment emphasizes that a neuron's dynamic range should be matched to both its receptive field and the statistical properties of the visual pattern expected within this field. Finally, the analysis is synthetic because it is an extension of the background suppression hypothesis (Barlow & Levick 1976), satisfies the redundancy reduction hypothesis (Barlow 1961 a, b) and is equivalent to deblurring under certain conditions (Ratliff 1965).

Single photon signals in fly photoreceptors and first order interneurones at behavioral threshold

1. The contrast sensitivity of the optomotor response of the fly Musca domestica was measured using a moving sinusoidal grating as the stimulus. In parallel experiments intracellular recordings were made from photoreceptors and first order visual interneurones to to determine their responses to the same threshold stimuli. Measurements of the spatial modulation transfer function for photoreceptors confirm that the optics of the eye were intact during recordings. 2. At the lowest intensity at which one can obtain an optomotor response, the photoreceptor signal is a train of discrete depolarizations, or bumps. With constant intensity stimuli, the temporal distribution of bumps followed the Poisson distribution with a mean rate of proportional to luminance. The mean bump rate at the threshold intensity for a behavioural response is 1.7 +/- 0.7 s-1 (mean +/- S.D., n = 25). 3. Calibrations and the statistical properties of the bump train indicate that a bump represents one effective photon, implying that the bump : photon ratios are quantum capture efficiencies. 4. At low intensities the first order interneurones (the large monopolar cells or LMCs) show hyperpolarizing bumps each triggered by a receptor bump. Using a point source stimulus, centred in the field of view, the LMC bump rate is six times that in a single receptor viewing the same stimulus, as expected from the known projection of six receptor axons to each LMC. When using an extended stimulus (the grating), the bump rate is 18-20 times that in receptors. Comparison with earlier work suggests that this increased lateral summation of receptor inputs to LMCs only occurs at very low intensities. 5. In both receptor and LMCs the amplitudes and wave forms of bumps depend upon the position of a point source stimulus within the field of view. With the light in the periphery of the field the bumps are smaller and slower than when the light is in the centre. This difference in response suggests that spatial stimulation is brought about by lateral interactions, possibly between receptors. 6. At higher mean intensities the signal-to-noise ratios in receptors responding to the appropriate threshold stimuli increase with intensity. This is suggestive of a decrease in the extent of spatial and/or temporal summation in the optomotor pathway.

Individual assignments of amide proton resonances in the proton NMR spectrum of the basic pancreatic trypsin inhibitor

Studies of proton-proton nuclear Overhauser effects were used to obtain individual assignments of 17 amide proton resonances in the 360 MHz proton nuclear magnetic resonance spectrum of the basic pancreatic trypsin inhibitor. First, optimizing the conditions for obtaining selective nuclear Overhauser effects in the presence of spin diffusion in macromolecules is discussed. Truncated driven nuclear Overhauser experiments were used to assing the amide proton resonances of the beta-sheet in the inhibitor. It is suggested that these techniques could serve quite generally to obtain individual resonance assignments in beta-sheet secondary structures of proteins. Combination of nuclear Overhauser studies with spin decoupling further resulted in individual assignments of the gamma-methyl resonances of the two isoleucines and numerous Calpha and Cbeta protons.