Development induces changes in sleep, and its duration has been reported to change as a function of aging. Additionally, sleep timing is a marker of pubertal maturation, where during adolescence, the ...circadian rhythm shifts later. Typically, this is manifested in a later sleep onset in the evening and later awakening in the morning. These changes across development seem to be universal around the world but are unlikely to persist into adulthood.
This study utilized accelerometer data from 17,355 participants aged 16–30 years (56% female) measured by validated Polar wearables over a 14-day period. We compared sleep duration, chronotype (sleep midpoint) and weekend catch-up (ie, social jetlag) sleep across ages and regions over 242,948 nights.
The data indicate a decline in sleep duration as well as a dramatic shift in sleep onset times throughout adolescence. This continues well into early adulthood and stabilizes nearer age 30. Differences in sleep duration across ages were significant, and ranged from 7:53 h at age 16 to 7:29 h at age 30 in the sample. Additionally, there was a clear difference between females and males throughout adolescence and young adulthood: girls had longer sleep duration and earlier timed sleep in the current study. Differences in sleep were found between regions across the world, and across European areas.
Both sleep duration and sleep timing go through a clear developmental pattern, particularly in early adulthood. Females had an earlier sleep midpoint and obtained more sleep. Regional differences in sleep occurred across the world.
•There is a steady decrease in sleep duration from age 16 to 30.•Sleep timing shifts later from 16 to 24 after which it becomes earlier again.•There are geographical differences in sleep duration and timing across the world.
Susceptibility to voice reactions during a histamine provocation test was studied in 21 asthmatics and 21 healthy subjects. Speech samples were recorded before, and 5 and 15 min after histamine ...inhalation, and the samples were rated by six speech pathologists. Deterioration of voice quality occurred in 2/12 asthmatic men and in 3/9 asthmatic women within 5 min after histamine inhalation; no change was observed between 5 and 15 min. Voice reactions were not related to the degree of bronchial obstruction: the subjects with the most pronounced decrease in peak expiratory flow (PEF) (60–61% in three subjects) did not develop voice reactions, and PEF did not decrease in one subject with voice reactions. No voice reactions were observed in the healthy subjects.
Thymic carcinoid tumours constitute less than 1% of all carcinoids, and differ markedly from true thymomas in natural history, morphology, prognosis and therapeutic options. New clinical and ...diagnostic modalities are described in two brothers with thymic carcinoid associated with multiple endocrine neoplasia syndrome. Octreotide scintigraphy proved useful for diagnosis and follow-up, and somatostatin receptor positivity may provide new prospects for treatment of non-resectable or recurrent tumour.
The daily rhythms of melatonin, cortisol and body temperature were studied in 16 institutionalized subjects with the Lennox-Gastaut syndrome. The results of 9 subjects with normal daily rhythms of ...sleep and wakefulness (group 1) were compared with those of 7 subjects with disordered sleep (group 2). Salivary samples were collected and axillary temperature was measured every 2 h during two or three separate 26-h periods. The hormones were measured by radioimmunoassays. The rhythms were characterized with single cosinor analysis. Two subjects in group 1 and six subjects in group 2 had abnormalities in their rhythms of temperature, cortisol or melatonin. All three rhythms were disrupted in two subjects of group 2. These two subjects were the only ones with disrupted cortisol rhythm. The diversity of rhythm pathologies suggested partly separate regulatory mechanisms for each rhythm. The co-occurrence of circadian rhythm sleep disorders with the deteriorated melatonin rhythm raised the question as to whether the sleep disorders of these subjects, like those of subjects with healthy brains, could be relieved by the induction of normal melatonin rhythm.
This study analyzed production of a long vowel sound within Finnish words by normal or dysphonic voices, using the Self-Organizing Map, the artificial neural network algorithm of T. Kohonen which ...produces two-dimensional representations of speech. The method was found to be both sensitive and specific in the detection of dysphonia. (Author/JDD)
A Baker-type linear independece measure is obtained for the values of generalized Heine series at non-zero points of an imaginary quadratic number field. This kind of estimate depends on the ...individual coefficients of the linear form, not only on the maximum of their absolute values.
The most anterior part of area 7 of awake, behaving macaque monkeys was investigated using single cell recording technique. Eighty-five cells from three hemispheres of two monkeys were isolated and ...studied. These cells showed more complex functional properties than the cells in the primary and secondary cortical fields. Of the cells 61% responded to somatosensory (26%) or visual (2%) or both somatosensory and visual (33%) stimulation; 39% of the cells were active only during the monkey's own movements. Most of the cells studied were active while the monkey was bringing an object to the mouth with its hand, when reaching for an object with lips, or while chewing. The neurons responded selectively to, e.g., palpation of the flexors of the arm, a visual stimulus approaching the face, passive movement of the monkey's hand towards the mouth, or they were active only when the monkey was reaching for an object with its lips or was mouthing it. The cellular activity in the anterolateral part of area 7 was prominently related to the stimulation or motor activity of the face (especially the mouth). In this respect, it differed from the more posterior part of area 7 adjacent to it. The results thus indicate that there is a separate and rather extensive mouth (or face) area in the parietal association cortex of the monkey.
The expression of "naming," "commanding," "angry," "frightened," "pleading," "astonished," "satisfied," "admiring," "scornful," and "sad" was with the word saara spoken by 12 subjects. Using the same ...connotations, the 120 utterances were categorized by 73 listeners. Most samples were agreed on by 50%-99% of the judges. Most samples of "astonished," "angry," "frightened," and "commanding" were judged as intended, while "pleading" was often confused with "sad," and "content" with "admiring." Acoustic differences between the categories were examined for F0, duration, and sound pressure; spectral features of aa were visualized with the self-organizing map of Kohonen. Most intraspeaker variation of mean F0, FO range, sound pressure, and duration took place during the aa segment. Peak sound pressure, mean FO, and spectral energy distribution of aa differentiated among "commanding," "angry," "frightened," "naming," and "sad.". Specific intonations of the aa segment were encountered for "astonished," "scornful," and "pleading.". The best-conveyed "admiring" samples were distinguished from "content" by spectral cues for a breathy voice quality.
Binding of 2-125Imelatonin to the anteroventral and anterodorsal nuclei of the rat limbic thalamus was analyzed with in vitro autoradiography. In both nuclei the binding was of high affinity (Kd ...values 24-41 pM) and was competed with by nanomolar concentrations of 6-hydroxymelatonin. Kd values were in the same range as those reported for other high-affinity binding sites in the brain. Bmax values were 0.68-2.99 fmol/mg protein. The results suggest that some effects of melatonin are mediated via the limbic thalamus.
Pineal melatonin is a putative humoral coordinator of various circadian body rhythms. Rather few loci in the brain contain such a density of melatonin receptors that specific binding can be ...demonstrated by autoradiography. In this study we measured, using in vitro receptor autoradiography, displaceable binding of iodo-melatonin to the anteroventral and anterodorsal thalamic nuclei of Wistar rats (0.6-1.4 fmol/mg protein at 100 pM ligand concentration). These nuclei of the limbic system have direct connections with the retina and they participate in learning and memory functions.
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