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Down syndrome regression disorder (DSRD) is a rare condition involving subacute cognitive decline, loss of previously acquired developmental skills, and prominent neuropsychiatric symptoms, particularly catatonia, in people with Down syndrome. It is thought to involve both autoimmune and neuropsychiatric mechanisms. Research, however, is largely restricted to case studies and retrospective case series and is particularly limited in terms of prospective longitudinal follow-up. We report a case study of a person with DSRD who received both immunomodulatory (intravenous immunoglobulin; IVIG) and psychiatric interventions (electroconvulsive therapy, ECT) over two years with regular assessments using caregiver and clinician ratings. This revealed a small, unsustained response to IVIG and a rapid, sustained response once ECT was introduced. The case highlights the importance of multimodal assessment involving multiple medical specialties, the need to trial different therapies due to the condition’s complexity, and the significant barriers that patients and their families face in accessing care.

Nineteen years of atmospheric composition measurements made at the University of Toronto Atmospheric Observatory (TAO; 43.66∘ N, 79.40∘ W; 174 m a.s.l.) are presented. These are retrieved from Fourier transform infrared (FTIR) solar absorption spectra recorded with an ABB Bomem DA8 spectrometer from May 2002 to December 2020. The retrievals have been performed for 14 species: O3, HCl, HF, HNO3, CH4, C2H6, CO, HCN, N2O, C2H2, H2CO, CH3OH, HCOOH, and NH3 using the SFIT4 algorithm. The measurements have been archived in the Network for the Detection of Atmospheric Composition Change (NDACC) data repository in Hierarchical Data Format version 4 (HDF4) files following the Generic Earth Observation Metadata Standard (GEOMS) and are also publicly available on Borealis, the Canadian Dataverse Repository (https://doi.org/10.5683/SP2/VC8JMC, Yamanouchi et al., 2022). In this paper, we describe the instrumentation, the retrieval strategy, the vertical sensitivity of the retrievals, the quality assurance process, and the error analysis of the TAO FTIR measurements and present the current version of the time series.

Abstract We report the results of an experiment in which electrophysiological activity was recorded from the human cerebellum and cerebrum in a sample of 14 healthy subjects before, during and after a classical eye blink conditioning procedure with an auditory tone as conditional stimulus and a maxillary nerve unconditional stimulus. The primary aim was to show changes in the cerebellum and cerebrum correlated with behavioral ocular responses. Electrodes recorded EMG and EOG at peri‐ocular sites, EEG from over the frontal eye‐fields and the electrocerebellogram (ECeG) from over the posterior fossa. Of the 14 subjects half strongly conditioned while the other half were resistant. We confirmed that conditionability was linked under our conditions to the personality dimension of extraversion‐introversion. Inhibition of cerebellar activity was shown prior to the conditioned response, as predicted by Albus (1971). However, pausing in high frequency ECeG and the appearance of a contingent negative variation (CNV) in both central leads occurred in all subjects. These led us to conclude that while conditioned cerebellar pausing may be necessary, it is not sufficient alone to produce overt behavioral conditioning, implying the existence of another central mechanism. The outcomes of this experiment indicate the potential value of the noninvasive electrophysiology of the cerebellum.

A new unsymmetrical dinucleating phosphino pyridyl 1,8-naphthyridine ligand PNNN is reported. Reaction with CuCl gave the dicopper complex [Cu2(μ-Cl)2(PNNN)] (1). In contrast, complexation of [RuCl2(cymene)]2 yielded a monometallic species [RuCl(cymene)(PNNN)]Cl ([2]Cl) in which the Ru is bound to the κ2-N,N, rather than κ2-P,N, binding pocket. The selective formation of the monoruthenium complex [2]Cl enabled synthesis of heterobimetallic complexes [RuCuCl3(cymene)(PNNN)] (3) and [RuCuCl2(cymene)(PNNN)]2[PF6]2 ([4]2[PF6]2), which both exhibit κ1-P coordination of Cu. Complexes 1 and [4]2[PF6]2 exhibit reversible dearomatisation–aromatisation behaviour at the metal–ligand cooperative methylene site upon sequential treatment with base (KOtBu) and acid (HCl). Notably, deprotonation of [4]2[PF6]2 induces a shift in the coordination mode of Cu to κ2-P,N. [ABSTRACT FROM AUTHOR]

We studied simultaneous EMG and midline EEG responses, including over the cerebellum, in 10 standing subjects (35 ± 15 yr; 5 females, 5 males). Recordings were made following repeated taps to the sternum, stimuli known to evoke short-latency EMG responses in leg muscles, consistent with postural reflexes. EEG power had relatively more high-frequency components (>30 Hz) when recorded from electrodes over the cerebellum (Iz and SIz) compared with other midline electrodes. We confirmed a previous report using a similar stimulus that evoked short-latency potentials over the cerebellum. We showed clear midline-evoked EEG potentials occurring at short latency over the cerebellum (P23, N31, N42, and P54) and frontally (N28 and N57) before the previously described perturbation-evoked potential (P1/N1/P2). The P23 response correlated with the subsequent EMG response in the tibialis anterior muscles (r = 0.72, P = 0.018), confirming and extending previous observations. We did not find a correlation with the N1 amplitude. We conclude that early activity occurs from electrodes over the inion in response to a brief tap to the sternum. This is likely to represent cerebellar activity and it appears to modulate short-latency postural EMG responses. NEW & NOTEWORTHY: We studied the effects of a brief tap to the sternum in human subjects, known to evoke short-latency postural responses. Using an extended EEG recording system, we showed early evoked responses over the midline cerebellum, including the P23 potential, which correlated with the EMG responses in tibialis anterior, consistent with a cerebellar role in postural reflexes. The stimulus also evoked later EEG responses, including the perturbation potential. [ABSTRACT FROM AUTHOR]

The genetic changes that occur in late stage metastatic melanoma are not well delineated. Here, the authors use rapid autopsy samples from metastatic melanoma patients and show that the late stage in the disease is characterised by whole genome doubling and aneuploidy.

Down syndrome regression disorder (DSRD) is a rare condition involving subacute cognitive decline, loss of previously acquired developmental skills, and prominent neuropsychiatric symptoms, particularly catatonia, in people with Down syndrome. It is thought to involve both autoimmune and neuropsychiatric mechanisms. Research, however, is largely restricted to case studies and retrospective case series and is particularly limited in terms of prospective longitudinal follow-up. We report a case study of a person with DSRD who received both immunomodulatory (intravenous immunoglobulin; IVIG) and psychiatric interventions (electroconvulsive therapy, ECT) over two years with regular assessments using caregiver and clinician ratings. This revealed a small, unsustained response to IVIG and a rapid, sustained response once ECT was introduced. The case highlights the importance of multimodal assessment involving multiple medical specialties, the need to trial different therapies due to the condition's complexity, and the significant barriers that patients and their families face in accessing care. [ABSTRACT FROM AUTHOR]

Although optical components in Fourier transform infrared (FTIR) spectrometers are preferably wedged, in practice, infrared spectra typically suffer from the effects of optical resonances (“channeling”) affecting the retrieval of weakly absorbing gases. This study investigates the level of channeling of each FTIR spectrometer within the Network for the Detection of Atmospheric Composition Change (NDACC). Dedicated spectra were recorded by more than 20 NDACC FTIR spectrometers using a laboratory mid-infrared source and two detectors. In the indium antimonide (InSb) detector domain (1900–5000 cm−1), we found that the amplitude of the most pronounced channeling frequency amounts to 0.1 ‰ to 2.0 ‰ of the spectral background level, with a mean of (0.68±0.48) ‰ and a median of 0.60 ‰. In the mercury cadmium telluride (HgCdTe) detector domain (700–1300 cm−1), we find even stronger effects, with the largest amplitude ranging from 0.3 ‰ to 21 ‰ with a mean of (2.45±4.50) ‰ and a median of 1.2 ‰. For both detectors, the leading channeling frequencies are 0.9 and 0.11 or 0.23 cm−1 in most spectrometers. The observed spectral frequencies of 0.11 and 0.23 cm−1 correspond to the optical thickness of the beam splitter substrate. The 0.9 cm−1 channeling is caused by the air gap in between the beam splitter and compensator plate. Since the air gap is a significant source of channeling and the corresponding amplitude differs strongly between spectrometers, we propose new beam splitters with the wedge of the air gap increased to at least 0.8∘. We tested the insertion of spacers in a beam splitter's air gap to demonstrate that increasing the wedge of the air gap decreases the 0.9 cm−1 channeling amplitude significantly. A wedge of the air gap of 0.8∘ reduces the channeling amplitude by about 50 %, while a wedge of about 2∘ removes the 0.9 cm−1 channeling completely. This study shows the potential for reducing channeling in the FTIR spectrometers operated by the NDACC, thereby increasing the quality of recorded spectra across the network.

Vestibular evoked myogenic potentials (VEMPs) are a useful and increasingly popular component of the neuro-otology test battery. These otolith-dependent reflexes are produced by stimulating the ears with air-conducted sound or skull vibration and recorded from surface electrodes placed over the neck (cervical VEMPs) and eye muscles (ocular VEMPs). VEMP abnormalities have been reported in various diseases of the ear and vestibular system, and VEMPs have a clear role in the diagnosis of superior semicircular canal dehiscence. However there is significant variability in the methods used to stimulate the otoliths and record the reflexes. This review discusses VEMP methodology and provides a detailed theoretical background for the techniques that are typically used. The review also outlines the common pitfalls in VEMP recording and the clinical applications of VEMPs. Keywords: Otolith, Sound, Vibration, Vestibular, VEMP, Method