Search results for "Apse"
showing 10 items of 1903 documents
The effects of short pulses of light at night on numbers of pineal "synaptic" ribbons and serotonin N-acetyltransferase activity in male Sprague-Dawl…
1986
To characterize further the functionally enigmatic "synaptic" ribbons (SR) of the mammalian pineal gland and to study possible relationships to melatonin synthesis, in the present investigation rats were exposed to short pulses of light at night when both SR numbers and serotonin N-acetyltransferase (NAT) activity are high in comparison to day-time values. Male Sprague-Dawley rats were killed at 13:00 and 01:00 h, respectively, and at 01:10 and 02:00 h after exposure to light for 10 and 60 min, respectively. The pineals were rapidly taken out and cut sagittally in half. One half was processed for electron-microscopic quantitation of SR numbers and the other half for NAT determinations. It w…
Correlation of the number of pineal ?synaptic? ribbons and spherules with the level of serum melatonin over a 24-hour period in male rabbits
1984
Previous studies have shown that pineal "synaptic" ribbons and spherules may respond differently under normal and experimental conditions. It has been suggested that the increase in the number of ribbons may be a prerequisite for enhanced melatonin formation. In the present study, the number of ribbons and spherules as well as the level of serum melatonin were monitored over a 24-h period in the male rabbit, the pineal gland of which is known to contain many spherules. It was found that both the number of ribbons and the levels of serum melatonin show the typical nocturnal increase, exhibiting peaks at 02:00 and 06:00 h, respectively. There is a good correlation (R = 0.8) of the two paramet…
Circadian and photoperiodic correlation between the number of pineal gland synaptic ribbons and serum melatonin levels in the rat.
1987
A study is made of the number of pineal gland synaptic ribbons in 35 maleWistar rats over a 24-hour period during the months of September and February, in correlation to the serum melatonin levels during the same periods and photophases.The results of the study confirm those reported by others authors and suggest that the synaptic ribbons may be the stimuli-transmitting organs facilitating pineal secretory function.
Synaptic ribbons of the rat pineal gland: responses to in-vivo and in-vitro treatment with inhibitors of protein synthesis.
1990
To elucidate the role of protein synthesis in the nocturnal increase of synaptic ribbons in the rat pineal gland, actinomycin-D, which inhibits transcription, and cycloheximide, an inhibitor of translation, were used. To assure that the drugs were effective and to relate morphological changes to pineal biosynthetic phenomena, the activity of N-acetyltransferase and levels of pineal indoleamine were measured. Results of in-vivo, short-term and long-term treatment with either drug suggest that transcription of proteins related to synaptic ribbon formation occurs during the first half of the light phase, whereas translation takes place during the first few hours of the dark phase. In contrast,…
Maturation changes the excitability and effective connectivity of the frontal lobe : A developmental TMS-EEG study
2019
The combination of transcranial magnetic stimulation with simultaneous electroencephalography (TMS–EEG) offers direct neurophysiological insight into excitability and connectivity within neural circuits. However, there have been few developmental TMS–EEG studies to date, and they all have focused on primary motor cortex stimulation. In the present study, we used navigated high‐density TMS–EEG to investigate the maturation of the superior frontal cortex (dorsal premotor cortex [PMd]), which is involved in a broad range of motor and cognitive functions known to develop with age. We demonstrated that reactivity to frontal cortex TMS decreases with development. We also showed that although fron…
Physical Activity and Body Composition in Children and Their Mothers According to Mother’s Gestational Diabetes Risk: A Seven-Year Follow-Up Study
2019
Background and Objectives: There is lack of knowledge on whether mothers&rsquo
Development of Children’s Actual and Perceived Motor Competence, Cardiorespiratory Fitness, Physical Activity, and BMI
2021
Purpose To examine synergistic associations between developmental trajectories of motor competence, perceived motor competence, cardiorespiratory fitness, moderate-to-vigorous physical activity (MVPA), and body mass index (BMI) from late childhood to adolescence. Methods In this 3-yr follow-up study, motor competence, perceived motor competence, cardiorespiratory fitness, MVPA, and BMI were assessed in 1167 Finnish school-age children (girls = 583, boys = 565; Mage = 11.27 ± 0.33). Moderate-to-vigorous physical activity was measured using hip-mounted accelerometers. Developmental trajectories were analyzed using latent growth curve modeling. Results The development of motor competence, card…
Developmental profiles of reading fluency and reading comprehension from grades 1 to 9 and their early identification.
2021
This study examined developmental profiles of reading fluency and reading comprehension in Grades 1 to 9 (ages 7 to 15) in a large Finnish sample (N = 2,518). In addition, early predictors of the profiles were analyzed with respect to kindergarten cognitive skills (phonological awareness, letter knowledge, rapid automized naming [RAN], number counting, word reading, vocabulary, and listening comprehension), parental factors (level of education, reading difficulties), and gender. Four different profiles of reading fluency and reading comprehension development were identified using latent profile analysis. These comprised one profile with persistent reading difficulties across the grades, one…
Sociodemographic Correlates of Parental Co-Participation in Digital Media Use and Physical Play of Preschool-Age Children
2021
Young children’s digital media use and physical activity have gained attention in recent research. Parental co-participation has a major impact on children’s health consequences. This study addressed a gap in the research by investigating daily parental co-participation in children’s digital media use and physical play, using the family ecological model theoretical framework. The participants in this nationally representative cross-sectional study were 2512 Finnish parents with two- to six-year-old children. Parents completed a questionnaire. Sociodemographic correlates of co-participation and of the awareness of guidelines regarding co-participation and correlation between co-participation…
Low dose of aPCC after the initial treatment in acquired haemophilia A is useful to reduce bleeding relapses: Data from the FAIR registry
2019
Background: Bypassing agents are the first line therapy in patients with acquired haemophilia A (AHA). Activated prothrombin complex concentrate (aPCC) proved to be effective as initial treatment, but 20% of patients (pts) had relapses. aPCC as short-term prophylaxis to reduce subsequent bleeds is still not clear. Aim: To evaluate whether a short-term prophylaxis with low dose of aPCC can reduce bleeding relapses after initial AHA treatment, maintaining safety. Methods: The FAIR Registry is a retrospective-prospective study started on December 2012, that collected data on all pts with AHA treated with aPCC in 12 Italian Haemophilia Centers. All statistical analyses were carried out in the 5…