Search results for "Rhythm"

The columnar gene vnd is required for tritocerebral neuromere formation during embryonic brain development of Drosophila.

2006

International audience; In Drosophila, evolutionarily conserved transcription factors are required for the specification of neural lineages along the anteroposterior and dorsoventral axes, such as Hox genes for anteroposterior and columnar genes for dorsoventral patterning. In this report, we analyse the role of the columnar patterning gene ventral nervous system defective (vnd) in embryonic brain development. Expression of vnd is observed in specific subsets of cells in all brain neuromeres. Loss-of-function analysis focussed on the tritocerebrum shows that inactivation of vnd results in regionalized axonal patterning defects, which are comparable with the brain phenotype caused by mutatio…

Hippocampal theta activity is selectively associated with contingency detection but not discrimination in rabbit discrimination-reversal eyeblink con…

2009

The relative power of the hippocampal theta-band ( approximately 6 Hz) activity (theta ratio) is thought to reflect a distinct neural state and has been shown to affect learning rate in classical eyeblink conditioning in rabbits. We sought to determine if the theta ratio is mostly related to the detection of the contingency between the stimuli used in conditioning or also to the learning of more complex inhibitory associations when a highly demanding delay discrimination-reversal eyeblink conditioning paradigm is used. A high hippocampal theta ratio was not only associated with a fast increase in conditioned responding in general but also correlated with slow emergence of discriminative res…

Regular theta-firing neurons in the nucleus incertus during sustained hippocampal activation

2015

This paper describes the existence of theta-coupled neuronal activity in the nucleus incertus (NI). Theta rhythm is relevant for cognitive processes such as spatial navigation and memory processing, and can be recorded in a number of structures related to the hippocampal activation including the NI. Strong evidence supports the role of this tegmental nucleus in neural circuits integrating behavioural activation with the hippocampal theta rhythm. Theta oscillations have been recorded in the local field potential of the NI, highly coupled to the hippocampal waves, although no rhythmical activity has been reported in neurons of this nucleus. The present work analyses the neuronal activity in t…

Nocturnal hormone profiles in patients with schizophrenia treated with olanzapine.

2005

Summary Nocturnal hormone profiles were measured in patients with schizophrenia with predominantly negative symptoms both under drug-free baseline conditions and after subchronic administration of the atypical antipsychotic olanzapine, with the aim of characterizing its pharmacological properties on the neuroendocrine level. The following hormones were studied in the sleep laboratory under polysomnographic control: adrenocorticotrophic hormone, cortisol, growth hormone (GH), prolactin, testosterone, and melatonin. Blood samples were taken at regular time intervals over the night, and serum concentrations of the hormones were determined. Ten patients completed the study, two of them were exc…

Behavioural sensitization to repeated sleep deprivation in a mice model of mania.

2008

Sensitization to the effect of stress has been hypothesized as a mechanism to explain episode recurrence and cycle acceleration in bipolar disorder. Naturalistic observations and experimental work in human patients suggested that sleep deprivation can trigger manic episodes of illness. In rats sleep deprivation (SD) with the platform method caused mania-like behaviours thus providing an animal model of mania with face, construct, and predictive validity. In the present study we administered SD or control stress to male CD1 mice following a dose-response protocol based on time of exposure to the experimental conditions (6, 12 or 24 h) and repetition of treatment (three times). SD, but not st…

Oxidant/antioxidant response of rhythmic gymnastics trainers following high intensity interval exercise training

2013

A Newly-Detected Reductase fromRauvolfiaCloses a Gap in the Biosynthesis of the Antiarrhythmic Alkaloid Ajmaline

2002

A new enzyme, 1,2-dihydrovomilenine reductase (E.C. 1.3.1), has been detected in Rauvolfia cell suspension cultures. The enzyme specifically converts 2beta( R)-1,2-dihydrovomilenine through an NADPH-dependent reaction into 17-O-acetylnorajmaline, a close biosynthetic precursor of the antiarrhythmic alkaloid ajmaline from Rauvolfia. A five-step purification procedure using SOURCE 30Q chromatography, hydroxyapatite chromatography, 2',5'-ADP Sepharose 4B affinity chromatography and ion exchange chromatography on DEAE Sepharose and Mono Q delivered an approximately 200-fold enriched enzyme in a yield of approximately 6%. SDS-PAGE showed an M r for the enzyme of approximately 48 kDa. Optimum pH …

FONEMĀTISKĀ RITMIKA BĒRNIEM AR FONĒTISKI FONEMATISIEM TRAUCĒJUMIEM

2021

Fonētiskā ritmika bērniem ar fonētiski fonemātiskiem traucējumiem Darba autore: Sabīne Siliča Zinātniskā vadītāja: Dr.paed., doc. Ilze Šūmane Diplomdarba apjoms: 54 lpp., 6 tabulas, 15 attēli, 8 pielikumi, izmantoti 41 literatūras avoti. Darbā analizēti fonētiski fonemātisko traucējumu teorētiskie aspekti, raksturotas 5-6 gadus vecu bērnu psiholoģiskās attīstības īpatnības, apkopota fonētiskās ritmikas teorētiskā bāze. Veikts pētījums, kurā ar anketēšanas palīdzību noskaidrots sabiedrības informētības līmenis par runas traucējumiem un iespējām to mazināšanai, viedoklis par fonētisko ritmiku, secināts par tās izmantošanas iespējām. Darbā piedāvāts fonētikās ritmikas vingrinājumu kopums un ek…

Recommendations of the European Cardiac Arrhythmia Society Committee on Device Failures and Complications

2006

Recommendations of the European Cardiac Arrhythmia Society Committee on Device Failures and Complications MASSIMO SANTINI,* JOHANNES BRACHMANN,† RICCARDO CAPPATO,‡ WYN DAVIES,§ JERONIMO FARRE,‖ SAMUEL LEVY,¶ AURELIO QUESADA,# RENATO P. RICCI,** EDWARD ROWLAND,†† NEIL SULKE‡‡ From *San Filipo Neri Hospital, Rome, Italy, †Klinikum Coburg, Germany, ‡Policlinico S. Donato, Milan, Italy, §St. Mary Hospital, London, UK, ‖Fundacion Jimenez Diaz, Madrid, Spain, ¶Hopital Nord des Bourrellys, Marseille, France, #Hospital General University of Valencia, Spain, **San Filippo Neri Hospital, ††St. George Medical School, London, UK, ‡‡Eastbourne General Hospital, Sussex, UK

Patterns of cercarial production from Diplostomum spathaceum: terminal investment or bet hedging?

2004

In the production of the infective cercariae of trematodes, the terminal investment hypothesis of life-history theory predicts that the rate of host exploitation and cercarial production should increase during the period of cercarial shedding since the reproductive value of the parasite decreases during this period. In contrast, a bet hedging hypothesis that focuses on the success of transmission when host contact rate is variable predicts that cercarial production should decrease in an attempt to keep the host alive for longer and thus would increase the probability of successful transmission. We examined these two hypotheses under laboratory conditions and recorded the production ofDiplos…