Brain chimeras for the study of an avian model of genetic epilepsy: structures involved in sound and light-induced seizures

The epileptic homozygotes of the Fayoumi strain of chickens (Fepi) are affected by photogenic reflex epilepsy with complete penetrance. Here we demonstrate that they are equally affected by audiogenic reflex epilepsy induced by intense sound stimulation. All the Fepi display sound-induced seizures from hatching to adulthood consisting of initial 'ictal arousal' and running fits usually followed by generalized clonico-tonic convulsions. A running fit is the preconvulsive motor symptom specifically induced by auditory stimulation while neck myoclonus is the preconvulsive motor symptom specifically induced by photic stimulation. The EEG interictal spikes and spike and waves are suppressed and replaced by a desynchronized trace during the seizures of both kinds. Viable neural chimeras were obtained by graft of embryonic brain vesicles from Fepi donors into normal chick embryos. Transfer of the complete audiogenic and photogenic phenotypes was obtained in chimeras resulting from embryonic substitution of both the prosencephalon and mesencephalon. The substitution of the prosencephalon alone resulted in transfer of interictal paroxysmal EEG activity accompanied by the sound and light-induced desynchronization and 'ictal arousal' with no motor seizures. Chimeras with embryonic substitution of the mesencephalon alone displayed running fits and convulsions induced by sound stimulation but only neck myoclonus following light stimulation. The conclusions are reached that: (i) the Fepi is a model of audiogenic and photogenic reflex epilepsy; (ii) in both types, the seizure initiator and the convulsion generator are localized in the brainstem, although reinforcement from telencephalic visual structures is needed to trigger photogenic generalized convulsions.     

Determination of urine saturation with computer program EQUIL 2 as a method for estimation of the risk of urolithiasis

Two measures of weight cycling and indexes of psychological functioning were examined in a large sample of dieters. History of weight cycling was assessed to include number of dieting attempts, total lifetime weight lost and regained, and number of weight cycles over 20 lb (9.1 kg). Experience of weight cycling measured perception of being a yo-yo dieter and perceived success at maintaining past weight losses. Experience was more strongly related than history to all psychological measures. Further, when controlling for the effects of age, body mass index, and experience, the relation between history and the psychological variables was nonsignificant. This finding suggests that an individual's perception of being a weight cycler may be more related to psychological problems than the actual number of pounds lost and regained over time.     

A Methodology for Data Schema Integration in the Entity Relationship Model

The conceptual design of databases is usually seen as divided into two steps: view modeling, during which user requirements are formally expressed by means of several user oriented conceptual schemata, and schema integration, whose goal is to merge such schemata into a unique global conceptual schema. This paper is devoted to describe a methodology for schema integration. An enriched entity relationship model is chosen as the data model. The integration process consists of three steps: first, several types of conflicts between the different user schemata are checked and solved; second, schemata are merged into a draft integrated schema, that is, third, enriched and restructured according to specific goals.     

Horseradish peroxidase localization of masticatory muscle motoneurons in cat

Horseradish peroxidase has been injected into individual masticatory muscles in young and adult cats in order to determine the topography of the corresponding groups of motoneurons in the motor nucleus of the Vth nerve. The results obtained show a clear dorsoventral somatotopic distribution; the superior muscles have their motoneurons located dorsally in the nucleus and the inferior muscles ventrally; the two main jaw closers, temporalis and masseter, are represented in the dorsal and central parts of the nucleus; located more ventrally are the motoneurons for the pterygoideus medialis and lateralis, the jaw closers and abductor muscles; finally motoneurons for the jaw openers, and the anterior belly of the digastricus and mylohyoideus, occupy the ventromedial part of the nucleus. All muscles have been found to be represented along the entire length of the nucleus, with the same dorsoventral layering.     

Design of statistical databases: A methodology for the conceptual step

The aim of the conceptual step in database design is to describe data involving in the application in a formal and abstract way, without any concern to the specific model and language chosen for the implementation. In statistical applications, data are described at different levels of aggregation, from elementary facts of the reality to complex aggregations such as classifications, time series, indexes. The paper describes a methodology for conceptual design of statistical databases that provides the designer suitable strategies for defining such different levels of aggregation starting from user requirements, and checking the completeness, coherence and minimality of the conceptual schema at the different levels. The methodology makes use of two data models for the representation of data: for elementary data the Entity-Relationship model, widely used in database applications, and for summary data a new model is proposed, designed to be an effective trade-off between expressive power and simplicity of use.     

The ortho effect makes manganese(III) meso-tetrakis(N-methylpyridinium-2-yl)porphyrin a powerful and potentially useful superoxide dismutase mimic

The ortho, meta, and para isomers of manganese(III) 5,10,15, 20-tetrakis(N-methylpyridyl)porphyrin, MnTM-2-PyP5+, MnTM-3-PyP5+, and MnTM-4-PyP5+, respectively, were analyzed in terms of their superoxide dismutase (SOD) activity in vitro and in vivo. The impact of their interaction with DNA and RNA on the SOD activity in vivo and in vitro has also been analyzed. Differences in their behavior are due to the combined steric and electrostatic factors. In vitro catalytic activities are closely related to their redox potentials. The half-wave potentials (E1/2) are +0.220 mV, +0.052 mV, and +0.060 V versus normal hydrogen electrode, whereas the rates of dismutation (kcat) are 6.0 x 10(7), 4.1 x 10(6), and 3.8 x 10(6) M-1 s-1 for the ortho, meta, and para isomers, respectively. However, the in vitro activity is not a sufficient predictor of in vivo efficacy. The ortho and meta isomers, although of significantly different in vitro SOD activities, have fairly close in vivo SOD efficacy due to their similarly weak interactions with DNA. In contrast, due to a higher degree of interaction with DNA, the para isomer inhibited growth of SOD-deficient Escherichia coli.     

Thiorphan stimulates clonal growth of GM-CFU in short-term cultures of bone marrow from a healthy donor and from patients with non-Hodgkin lymphoma

Thiorphan, a specific inhibitor of membrane neutral endopeptidase (NEP, EC 3.4.24.11) also known as the common acute lymphoblastic leukemia antigen (CALLA, CD10) was added into short-term clonal cultures of the buffy coat concentrates of human bone marrow obtained from a healthy donor (six experiments) and from ten patients with non-Hodgkin lymphoma (NHL) (eight in complete remission, one in partial remission and one in relapse). Thiorphan concentrations ranged from 10(-5) to 10(-13) M. Nanomolar and higher concentrations of the drug mildly stimulated the granulocyte-macrophage colony-forming unit (GM-CFU) counts in the cultures of normal bone marrow, reaching the significance at 10(-7) M. Meaningful alterations of the GM-CFU counts were noted in 31 of 79 thiorphan-treated cultures of NHL bone marrow (39%). In those cultures the stimulatory effects (33%) outnumbered the inhibitory ones (6%). The stimulatory effects occurred mainly in the bone marrow samples of the patients with highly malignant NHL. The observations are compatible with the idea that the membrane endopeptidase (CALLA, CD10) participates in processes controlling the proliferation and differentiation of hematopoetic cells by cleaving the neuropeptides and related hemoregulatory peptides.