The significance of anti-neuronal antibodies for acute psychiatric disorders: a retrospective case–controlled study

Background

The clinical significance of anti-neuronal antibodies in patients with psychiatric disorders, but without encephalitis, remains unknown. In patients admitted to acute psychiatric inpatient care we aimed to identify clinical features distinguishing anti-neuronal antibody positive patients from matched controls.

Results

Patients who were serum-positive to N-methyl d-aspartate receptor (NMDAR) (n?=?21), contactin-associated protein 2 (CASPR2) (n?=?14) and/or glutamic acid decarboxylase 65 (GAD65) (n?=?9) antibodies (cases) were age and sex matched (1:2) with serum-negative patients from the same cohort (controls). The prevalence and severity of psychiatric symptoms frequently encountered in NMDAR, CASPR2 and GAD65 antibody associated disorders were compared in cases and controls. NMDAR, CASPR2 and GAD65 antibody positive patients did not differ in their clinical presentation from matched serum negative controls.

Conclusion

In this cohort, patients with and without NMDAR, CASPR2 and GAD65 antibodies admitted to acute psychiatric inpatient care had similar psychiatric phenotypes. This does not exclude their clinical relevance in subgroups of patients, and studies further investigating the clinical significance of anti-neuronal antibodies in patients with psychiatric symptomatology are needed.

     

Measurements and predictions of hooded crow (Corvus corone cornix) call propagation over open field habitats

In a study of hooded crow communication over open fields an excellent correspondence is found between the attenuation spectra predicted by a "turbulence-modified ground effect plus atmospheric absorption" model, and crow call attenuation data. Sound propagation predictions and background noise measurements are used to predict an optimal frequency range for communication ("sound communication window") from an average of crow call spectra predicted for every possible combination of the sender/receiver separations 300, 600, 900, and 1200 m and heights 3,6,9 m thereby creating a matrix assumed relevant to crow interterritorial communication. These predictions indicate an optimal frequency range for sound communication between 500 Hz and 2 kHz. Since this corresponds to the frequency range in which crow calls have their main energy and crow hearing in noise is particularly sensitive, it suggests a specific adaptation to the ground effect. Sound propagation predictions, together with background noise measurements and hearing data, are used to estimate the radius of the hooded crow active space. This is found to be roughly 1 km in moderately windy conditions. It is concluded that the propagation modeling of the sort introduced here could be used for assessing the impact of human noise on animal communication.     

Experimental investigation of the plasma-wall transition

We report on measurements of the ion velocity distribution as a function of distance to a target immersed in a magnetized argon plasma. Two situations are investigated: (a) practically the whole plasma streams onto a large target, and (b) the size of the target is significantly smaller than the plasma diameter. The Mach number M=u/c_{s} decreases from M=1 at the target surface to values around 0.5 at a typical scale of lambda_{a}=30 mm and lambda_{b}=5 mm, respectively. In order to explain these small decay lengths, the measurements of case (a) are compared with a source-diffusion model and those of (b) to Hutchinson's model. In (a) good agreement between modeling and experiment is obtained assuming a low neutral gas temperature. The data in (b) also agree excellently with modeled profiles, although the large fitting parameter D=20 m;{2}/s indicates that other processes than diffusion contribute significantly to the transport.     

Hysteresis and scanning behavior of mesoporous molecular sieves

Sorption hysteresis is a widely studied phenomenon whose predicted behavior is well documented and researched. On the other hand, there is much less known about the region that lies between sorption isotherms, believed to be a metastable region. Scanning curves are a way of understanding the mechanism of hysteresis and a tool for hysteresis model validation. Scanning curves were produced for mesoporous materials: SBA-15 and MCM-41 for N(2) sorption at 77 K and Ar sorption at 87 K. A limited set of different scanning behaviors is identified. Like most hysteresis theories, it was found that a single model for scanning behavior cannot be extended to all materials under the same or different experimental conditions. Two behaviors are consistent with recent theories and simulations; however, several are not. The implications as to the characterization of pore dimensions and structure are discussed.     

Electronic structure,electrical and magnetic properties of RMo(8)O(14) compounds (R = La,Ce, Pr,Nd, Sm) containing bicapped Mo(8) clusters

Magnetic and electrical resistivity properties of RMo(8)O(14) (R = La, Ce, Pr, Nd, Sm) compounds containing different bicapped-octahedral Mo(8) clusters are discussed. Extended Hückel (EH) molecular calculations were carried out in order to study the influence of the position of metal capping atoms on the electronic structure of different Mo(8) isomers. Different optimal metal electron counts are possible for these clusters. Periodic density functional calculations confirm the molecular character of these compounds and allow the understanding of their semiconducting and magnetic properties.     

Optimizing delays in the MBOB,broadband HMBC,and broadband XLOC NMR pulse sequences

The MBOB, broadband HMBC, and broadband XLOC NMR pulse sequences (A. Meissner and O. W. S?rensen (2000, Magn. Reson. Chem. 38, 981-984; 2001, 39, 49-52)) were introduced as a means of obtaining heteronuclear long-range correlation spectra with broadband excitation over an interval of heteronuclear long-range J coupling constants. However, it is not trivial what combination of delays to choose for a given purpose, particularly if one-bond and long-range correlation spectra are obtained simultaneously as in MBOB. This paper presents a way to determine sets of delays for MBOB, broadband HMBC, and broadband XLOC resolving the problem. The results tabulated suit various ranges of J coupling constants and transverse relaxation times.     

Synthesis of O-glycolyl-linked neuraminic acids through a spirocyclic intermediate

[reaction: see text] The neuraminic acid derivative 5 is readily converted in several steps to the neuraminic acid dimer 12, linked through the hydroxyl of a 5-N-glycolyl group in an alpha-2,5 glycosidic linkage. The sequence is shown to proceed through a spirocyclic intermediate 9 by in situ NMR experiments. Similar derivatives of N-glycolylneuraminic acid (Neu5Gc), including polymers, have been identified from marine sources, including starfish and sea urchins, often as sulfated derivatives and are thought to mediate sperm-egg recognition.     

Electron-impact promoted fragmentation of some substituted isoxazolidines

A series of substituted isoxazolidinylacetophenones (II to VI) have been shown to fragment subsequent to electron-impact in a generally predictable fashion. One characteristic fragmentation of all the compounds investigated was the loss of H₂O₂ from their respective molecular ions.     

Beyond the T1 limit: singlet nuclear spin states in low magnetic fields

Low-field nuclear spin singlet states may be used to store nuclear spin order in a room temperature liquid for a time much longer than the spin-lattice relaxation time constant T1. The low-field nuclear spin singlets are unaffected by intramolecular dipole-dipole relaxation, which is generally the predominant relaxation mechanism. We demonstrate storage of nuclear spin order for more than 10 times longer than the measured value of T1. This phenomenon may facilitate the development of nuclear spin hyperpolarization methods and may allow the study of motional processes which occur too slowly for existing NMR techniques. This is the first time that the memory of nuclear spins has been extended well beyond the T1 limit in a system lacking intrinsic magnetic equivalence.