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Introduction: Subacute adult‐acquired hemichorea is a striking presentation with a broad differential, including ischemic, metabolic, and inflammatory causes. Case: We encountered a 74‐year‐old woman with rapid onset of hemichorea and associated encephalopathy. Following a thorough workup without identification of clear imaging or laboratory abnormalities, we empirically treated with IVIg. Her hemichorea dramatically improved. Due to relapses of hemichorea, she required repeat immunotherapy with IVIg or high dose steroids followed by maintenance mycophenolate. Discussion: This case of seronegative autoimmune hemichorea highlights the importance of a high index of suspicion for an inflammatory etiology of chorea when other causes are ruled out and performing an immunotherapy trial. [ABSTRACT FROM AUTHOR]

The attempt to obtain phenoxypicramide from a classical nucleophilic substitution reaction using as reagents phenoxyamine and picryl chloride unexpectedly led to the formation of 1,3-dinitro-10H-phenoxazine. The possible mechanisms of formation, involving a molecular rearrangement with expelling of a nitro group, are discussed. [ABSTRACT FROM AUTHOR]

Through the importance of the number three in our culture and the strange preference for a ternary pattern of our nature one can perceive how and why number theory degraded to numerology. The strong preference of our minds for simple patterns can be read as the key to understanding not only the development of numerology, but also why scientists were and are prone to give their discoveries or creations a structure that is based on simple patterns and, among them, especially the ternary pattern. If some numbers seem to appear quite often throughout the fabric of reality, like zero, one, two, and three, reality has, nevertheless, been preferentially analysed in a way to enhance its ternary character. The present excursion through some scientific domains where the ternary pattern has been used tries to offer an answer to the fascination that some numbers, and patterns based on them, exerted and exerts, even today, on human minds. Throughout the overall models created by the human mind, be they natural or spiritual, the models based on a "unary" and on a "dualistic" pattern are surely important, but the model based on a ternary pattern ended up assuming an archetypical character, which is quite intriguing, and deserves to be deepened. The paper is a useful resource for projects for students and background material for teachers of mathematics touching, as it does, on biology, chemistry and physics.

IgG4-related disease-associated hypertrophic pachymeningitis (IgG4RD-HP) is a fibroinflammatory autoimmune disorder in which diagnosis is difficult without biopsy. Guidance on management of disease refractory to glucocorticoids and intravenous rituximab is limited. We present the case of a 68-year-old woman with IgG4RD-HP who developed sensorineural hearing loss with associated bulky basilar pachymeningeal enhancement. Her cerebrospinal fluid was inflammatory and had an elevated IgG4 concentration, strongly suggestive of IgG4RD-HP. Biopsy of involved meninges was not possible due to surgical risk. Over years she developed bilateral optic neuropathies and hydrocephalus, requiring intravenous rituximab and ventriculoperitoneal shunt. Her disease was refractory to glucocorticoids. Despite maintenance intravenous rituximab, she developed slowly progressive symptoms of intracranial hypertension and hydrocephalus with persistently inflammatory spinal fluid. Switching to intrathecal rituximab therapy led to dramatic improvement in gait and headache and reduced pachymeningeal bulk and metabolic activity. In patients with IgG4RD-HP refractory to glucocorticoids and intravenous rituximab, intrathecal rituximabmay be an efficacious therapy. [ABSTRACT FROM AUTHOR]

In a series of earlier studies, it was established that benzoannelation in the angular (resp. linear) position relative to a ring R of a polycyclic conjugated π-electron system, increases (resp. decreases) the intensity of the cyclic conjugation in the ring R. Herein, it is shown how this regularity can be explained by means of a simple, Kekulé-structurebased argument, itself based on an idea of Randić from the 1970s.

Two experiments investigated lateral asymmetries in eight-month-olds' perception of contour-altered and contour-preserved melody changes. Found that infants who heard a contour-altered change showed a left-ear advantage, whereas infants who heard a contour-preserved change showed a right-ear advantage. The pattern of lateralization for melody change detection may reflect more general hemispheric processing differences in early organization of auditory information processing. (Author/KB)

A modified Dimensional Change Card Sort (DCCS) task was used to test cognitive flexibility in adult cotton-top tamarins and children aged 19 months to 60 months. Subjects had to infer a rule from the experience of selecting between two cards to earn a reward, and the pairs of stimuli defined the rule (e.g., pick blue ones, not red ones, or pick trucks, not boats). Two different tests measured subjects' ability to shift to a reversal of the rule (intradimensional shift) and to shift to a new rule defined by a dimension previously irrelevant (interdimensional shift). Both adult tamarins and children aged 49-60 months were able to learn the initial rule and switch to a reversal and to a rule based on a different dimension. In contrast, the two younger groups of children, aged 19-36 months and aged 37-48 months, could switch when a reversal was imposed but took significantly longer to learn a new rule on a former irrelevant dimension. Experiment 2 presented a wider set of novel stimuli which shared some features with the original set to further explore the basis of rule learning. The result was that tamarins and 52-to 60-month-old children both chose novel stimuli that fit the rule and had no a priori associative strength, suggesting a rule application not solely based on associative strength. Importantly, novel items introduced some risk for choice, and children showed themselves to be risk-averse, whereas tamarins were risk-prone within a novel context. [ABSTRACT FROM AUTHOR]

A quantitative structure-property relationship (QSPR) study is presented for exploring the physical properties of catafusenes (cata-condensed benzenoids). Cata-condensed benzenoid hydrocarbons have some physical properties that depend in large measure on the presence of linearly condensed benzenoid rings that is parameter n and bulk properties that reflect in a large measure the weak intermolecular forces.

Byline: Alexandru T. Balaban (1), Milan Randic (2) Keywords: local aromaticity; Clar structures; Kekule structures; polycyclic hydrocarbons Abstract: By adopting the convention that shared double bonds in polycyclic conjugated hydrocarbons contribute with one [pi]-electron and unshared ones with two [pi]-electrons, a partition of [pi]-electrons in each ring ([pi]-electron content, EC) can be obtained by averaging over all Kekule structures, which are assumed to have equal weights. This affords a simple measure of local aromaticity that is comparable with other such local aromaticity indices in polycyclic benzenoids. Author Affiliation: (1) Texas A &amp M University at Galveston, MARS, 5007 Avenue U, Galveston, TX, 77551, USA (2) Milan Randic, 3225 Kingman Rd, Ames, IA, 50014, USA Article History: Registration Date: 03/12/2004 Received Date: 17/09/2004

Byline: Damir Vukicevic (1), Milan Randic (2), Alexandru T. Balaban (3) Keywords: polycyclic benzenoid hydrocarbons; algebraic vs. geometric Kekule structures Abstract: A rigorous proof is provided for the theorem on the necessary and sufficient conditions for the algebraic Kekule structure of a peri-condensed or corona-condensed benzenoid hydrocarbon to correspond to more than one geometric Kekule structure. Author Affiliation: (1) Department of Mathematics, University of Split, Nikole Tesle 12, 21000, Split, Croatia (2) 3225 Kingman Road, Ames, IA, 50014, USA (3) Department of Marine Sciences, Texas A &amp M University at Galveston, 5007 Avenue U, Galveston, TX, 77551, USA Article History: Registration Date: 27/10/2004

Heterocyclic chemistry offers a much wider prospect for exploring the possibilities and limitations of the aromaticity concept than hydrocarbon chemistry. Quantitative measures for aromaticity have been devised, and improved molecular calculation methods, which allow for a better evaluation of the experimental data already obtained and predictions of novel aromatic heterocycles.