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https://www.readbyqxmd.com/read/28100283/genetic-influences-on-hormonal-markers-of-chronic-hypothalamic-pituitary-adrenal-function-in-human-hair
#1
E M Tucker-Drob, A D Grotzinger, D A Briley, L E Engelhardt, F D Mann, M Patterson, C Kirschbaum, E K Adam, J A Church, J L Tackett, K P Harden
BACKGROUND: Cortisol is the primary output of the hypothalamic-pituitary-adrenal (HPA) axis and is central to the biological stress response, with wide-ranging effects on psychiatric health. Despite well-studied biological pathways of glucocorticoid function, little attention has been paid to the role of genetic variation. Conventional salivary, urinary and serum measures are strongly influenced by diurnal variation and transient reactivity. Recently developed technology can be used to measure cortisol accumulation over several months in hair, thus indexing chronic HPA function...
January 19, 2017: Psychological Medicine
https://www.readbyqxmd.com/read/28094875/neuroendocrinology-of-mast-cells-challenges-and-controversies
#2
REVIEW
Theoharis C Theoharides
Mast cells (MC) are hemopoietically-derived tissue immune cells that are ubiquitous in the body, including neuroendocrine organs such as the hypothalamus, pineal, pituitary, ovaries, pancreas and uterus where their action is not well understood. Mast cells have historically been associated with allergies because of their rich content of histamine and tryptase, but more recently with regulation of immunity and inflammation due their synthesis and release of numerous cytokines and chemokines. Mast cells are located perivascularly and express numerous receptors for diverse ligands such as allergens, pathogens, neurotransmitters, neuropeptides and hormones including acetylcholine, calcitonin gene-related peptide (CGRP), corticosteroids, corticotropin-releasing hormone (CRH), β-endorphin, epinephrine, 17β-estradiol, gonadotrophins, hemokinin-A (HKA), leptin, melatonin, neurotensin (NT), parathyroid hormone (PTH), substance P (SP) and vasoactive instestinal peptide (VIP)...
January 17, 2017: Experimental Dermatology
https://www.readbyqxmd.com/read/28087763/circadian-kinetics-of-cell-cycle-progression-in-adult-neurogenic-niches-of-a-diurnal-vertebrate
#3
Veronica Akle, Alexander J Stankiewicz, Vasili Kharchenko, Lili Yu, Peter V Kharchenko, Irina V Zhdanova
: The circadian system may regulate adult neurogenesis via intracellular molecular clock mechanisms or by modifying the environment of neurogenic niches, with daily variation in growth factors or nutrients depending on the animal's diurnal or nocturnal life-style. In a diurnal vertebrate, zebrafish, we studied circadian distribution of immunohistochemical markers of the cell division cycle (CDC) in five of the sixteen neurogenic niches of adult brain, the dorsal telencephalon, habenula, preoptic area, hypothalamus and cerebellum...
January 13, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28078345/comparison-between-the-optical-properties-of-aerosols-in-the-fine-and-coarse-fractions-over-valladolid-spain
#4
S Mogo, J F López, V E Cachorro, A de Frutos, R Zocca, A Barroso, D Mateos, E Conceição
Continuous measurements of the optical properties of aerosol particles have been made at Valladolid, Spain, covering the period from June 2011 to July 2012. The measurements were made at two size cuts: sub-10 μm and sub-1 μm (PM10 and PM1). The data measured were the scattering and backscattering coefficients, σs and σbs, obtained from an integrating nephelometer, and the absorption coefficient, σa, obtained from a particle soot absorption photometer. Spectrally resolved data were obtained from both instruments at 3 wavelengths (blue/green/red) at low relative humidity (RH < 40%)...
January 12, 2017: Environmental Science. Processes & Impacts
https://www.readbyqxmd.com/read/28076306/parallel-diurnal-fluctuation-of-testosterone-androstenedione-dehydroepiandrosterone-and-17ohprogesterone-as-assessed-in-serum-and-saliva-validation-of-a-novel-liquid-chromatography-tandem-mass-spectrometry-method-for-salivary-steroid-profiling
#5
Marco Mezzullo, Alessia Fazzini, Alessandra Gambineri, Guido Di Dalmazi, Roberta Mazza, Carla Pelusi, Valentina Vicennati, Renato Pasquali, Uberto Pagotto, Flaminia Fanelli
BACKGROUND: Salivary androgen testing represents a valuable source of biological information. However, the proper measurement of such low levels is challenging for direct immunoassays, lacking adequate accuracy. In the last few years, many conflicting findings reporting low correlation with the serum counterparts have hampered the clinical application of salivary androgen testing. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) makes it possible to overcome previous analytical limits, providing new insights in endocrinology practice...
January 11, 2017: Clinical Chemistry and Laboratory Medicine: CCLM
https://www.readbyqxmd.com/read/28065371/real-t1-relaxation-time-measurement-and-diurnal-variation-analysis-of-intervertebral-discs-in-a-healthy-population-of-50-volunteers
#6
J Galley, G Maestretti, G Koch, H-M Hoogewoud
PURPOSE: To measure the real T1 relaxation time of the lumbar intervertebral discs in a young and healthy population, using different inversion recovery times, and assess diurnal variation. MATERIAL AND METHODS: Intervertebral discs from D12 to S1 of 50 healthy volunteers from 18 to 25 years old were evaluated twice the same day, in the morning and in the late afternoon. Dedicated MRI sequences with different inversion recovery times (from 100 to 2500ms) were used to calculate the real T1 relaxation time...
February 2017: European Journal of Radiology
https://www.readbyqxmd.com/read/28060525/diurnal-rhythms-in-psychological-reward-functioning-in-healthy-young-men-wanting-liking-and-learning
#7
Jamie E M Byrne, Greg Murray
A range of evidence suggests that human reward functioning is partly driven by the endogenous circadian system, generating 24-hour rhythms in behavioural measures of reward activation. Reward functioning is multifaceted but literature to date is largely limited to measures of self-reported positive mood states. The aim of this study was to advance the field by testing for hypothesised diurnal variation in previously unexplored components of psychological reward: 'wanting', liking, and learning using subjective and behavioural measures...
January 6, 2017: Chronobiology International
https://www.readbyqxmd.com/read/28057622/seasonal-ambient-changes-influence-inpatient-falls
#8
Chie Magota, Hiroyuki Sawatari, Shin-Ichi Ando, Mari K Nishizaka, Kaoru Tanaka, Kaori Horikoshi, Izumi Hoashi, Hashiguchi Nobuko, Tomoko Ohkusa, Akiko Chishaki
BACKGROUND: falls by inpatients often result in serious injuries and deterioration in a patient's physical abilities and quality of life, especially among older individuals. Although various factors have been found to be associated with falls, the combined effects of behavioural and ambient factors are not fully evaluated. OBJECTIVE: we investigated the influence of both behavioural and ambient factors on inpatient falls, focusing on seasonal and diurnal variations...
January 4, 2017: Age and Ageing
https://www.readbyqxmd.com/read/28042677/contrasting-patterns-of-cytokinins-between-years-in-senescing-aspen-leaves
#9
Erik Edlund, Ondrej Novak, Michal Karady, Karin Ljung, Stefan Jansson
Cytokinins are plant hormones that typically block or delay leaf senescence. We profiled 34 different cytokinins/cytokinin metabolites (including precursors, conjugates and degradation products) in leaves of a free-growing mature aspen (Populus tremula) before and after the initiation of autumnal senescence over three consecutive years. The levels and profiles of individual cytokinin species, or classes/groups, varied greatly between years, despite the fact that the onset of autumn senescence was at the same time each year, and senescence was not associated with depletion of either active or total cytokinin levels...
January 1, 2017: Plant, Cell & Environment
https://www.readbyqxmd.com/read/28042668/leaf-water-18-o-and-2-h-enrichment-along-vertical-canopy-profiles-in-a-broadleaved-and-a-conifer-forest-tree
#10
Rebekka Bögelein, Frank M Thomas, Ansgar Kahmen
Distinguishing meteorological and plant mediated drivers of leaf water isotopic enrichment is prerequisite for ecological interpretations of stable hydrogen and oxygen isotopes in plant tissue. We measured input and leaf water δ(2) H and δ(18) O as well as micrometeorological and leaf morpho-physiological variables along a vertical gradient in a mature angiosperm (European beech) and gymnosperm (Douglas fir) tree. We used these variables and different enrichment models to quantify the influence of Péclet and non-steady state effects and of the biophysical drivers on leaf water enrichment...
January 1, 2017: Plant, Cell & Environment
https://www.readbyqxmd.com/read/28036073/target-detection-over-the-diurnal-cycle-using-a-multispectral-infrared-sensor
#11
Huijie Zhao, Zheng Ji, Na Li, Jianrong Gu, Yansong Li
When detecting a target over the diurnal cycle, a conventional infrared thermal sensor might lose the target due to the thermal crossover, which could happen at any time throughout the day when the infrared image contrast between target and background in a scene is indistinguishable due to the temperature variation. In this paper, the benefits of using a multispectral-based infrared sensor over the diurnal cycle have been shown. Firstly, a brief theoretical analysis on how the thermal crossover influences a conventional thermal sensor, within the conditions where the thermal crossover would happen and why the mid-infrared (3~5 μm) multispectral technology is effective, is presented...
December 29, 2016: Sensors
https://www.readbyqxmd.com/read/28033569/temporal-and-diurnal-analysis-of-trace-elements-in-the-cryospheric-water-at-remote-laohugou-basin-in-northeast-tibetan-plateau
#12
Zhiwen Dong, Shichang Kang, Dahe Qin, Xiang Qin, Fangping Yan, Wentao Du, Ting Wei
An evaluation of glacial meltwater chemistry is needed under recent dramatic glacier melting when water resources might be significantly impacted. This study investigated trace elements variation in the meltwater stream, and its related aquatic environmental information, at the Laohugou (LHG) glacier basin (4260 m a.s.l.) at a remote location in northeast Tibetan Plateau. We focused on the spatial, temporal and diurnal change of trace elements during the glacier ablation period. Results showed evident elements spatial difference on the glacier surface meltwater, as most of the elements showed increased concentration at the terminus compared to higher elevations sites...
December 19, 2016: Chemosphere
https://www.readbyqxmd.com/read/28031812/dominance-in-a-ground-dwelling-ant-community-of-banana-agroecosystem
#13
Dominique Carval, Violaine Cotté, Rémi Resmond, Benjamin Perrin, Philippe Tixier
In tropical ecosystems, ants represent a substantial portion of the animal biomass and contribute to various ecosystem services, including pest regulation and pollination. Dominant ant species are known to determine the structure of ant communities by interfering in the foraging of other ant species. Using bait and pitfall trapping experiments, we performed a pattern analysis at a fine spatial scale of an ant community in a very simplified and homogeneous agroecosystem, that is, a single-crop banana field in Martinique (French West Indies)...
December 2016: Ecology and Evolution
https://www.readbyqxmd.com/read/28030646/tree-circumference-dynamics-in-four-forests-characterized-using-automated-dendrometer-bands
#14
Valentine Herrmann, Sean M McMahon, Matteo Detto, James A Lutz, Stuart J Davies, Chia-Hao Chang-Yang, Kristina J Anderson-Teixeira
Stem diameter is one of the most commonly measured attributes of trees, forming the foundation of forest censuses and monitoring. Changes in tree stem circumference include both irreversible woody stem growth and reversible circumference changes related to water status, yet these fine-scale dynamics are rarely leveraged to understand forest ecophysiology and typically ignored in plot- or stand-scale estimates of tree growth and forest productivity. Here, we deployed automated dendrometer bands on 12-40 trees at four different forested sites-two temperate broadleaf deciduous, one temperate conifer, and one tropical broadleaf semi-deciduous-to understand how tree circumference varies on time scales of hours to months, how these dynamics relate to environmental conditions, and whether the structure of these variations might introduce substantive error into estimates of woody growth...
2016: PloS One
https://www.readbyqxmd.com/read/28029289/effects-of-diurnal-variation-and-anesthetic-agents-on-intraocular-pressure-in-syrian-hamsters-mesocricetus-auratus
#15
Seyed Mehdi Rajaei, Maneli Ansari Mood, Mohammad Reza Paryani, David L Williams
OBJECTIVE To determine effects of diurnal variation and anesthetic agents on intraocular pressure (IOP) in Syrian hamsters (Mesocricetus auratus). ANIMALS 90 healthy adult Syrian hamsters (45 males and 45 females). PROCEDURES IOP was measured with a rebound tonometer. In phase 1, IOP was measured in all hamsters 3 times during a 24-hour period (7 am, 3 pm, and 11 pm). In phase 2, hamsters were assigned to 5 groups (18 animals [9 males and 9 females]/group). Each group received an anesthetic agent or combination of anesthetic agents (ketamine hydrochloride, xylazine hydrochloride, diazepam, ketamine-diazepam [KD], or ketamine-xylazine [KX] groups) administered via the IP route...
January 2017: American Journal of Veterinary Research
https://www.readbyqxmd.com/read/28013051/diurnal-variations-in-polyunsaturated-fatty-acid-contents-and-expression-of-genes-involved-in-their-de-novo-synthesis-in-pigs
#16
Xihong Zhou, Dan Wan, Yumei Zhang, Yiming Zhang, Cimin Long, Shuai Chen, Liuqin He, Bie Tan, Xin Wu, Yulong Yin
The daily variations in circulating fatty acid (FA) contents and lipid metabolism have been well documented. However, whether long chain polyunsaturated FA (PUFA) contents and expression of genes involved in their de novo synthesis exhibit daily rhythms are yet unknown. We conducted the present study to investigate the daily variations in PUFA contents in plasma and liver of pigs. Moreover, diurnal expression of genes encode fatty acid desaturases and elongases, which are key enzymes catalyzed de novo synthesis of long chain PUFA, were also explored...
December 21, 2016: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/28007048/non-invasive-individual-methane-measurement-in-dairy-cows
#17
E Negussie, J Lehtinen, P Mäntysaari, A R Bayat, A-E Liinamo, E A Mäntysaari, M H Lidauer
Attempts to lower the environmental footprint of milk production needs a sound understanding of the genetic and nutritional basis of methane (CH4) emissions from the dairy production systems. This in turn requires accurate and reliable techniques for the measurement of CH4 output from individual cows. Many of the available measurement techniques so far are either slow, expensive, labor intensive and are unsuitable for large-scale individual animal measurements. The main objectives of this study were to examine and validate a non-invasive individual cow CH4 measurement system that is based on photoacoustic IR spectroscopy (PAS) technique implemented in a portable gas analysis equipment (F10), referred to as PAS-F10 method and to estimate the magnitude of between-animal variations in CH4 output traits...
December 23, 2016: Animal: An International Journal of Animal Bioscience
https://www.readbyqxmd.com/read/28002028/within-day-biological-variation-and-hour-to-hour-reference-change-values-for-hematological-parameters
#18
Judith M Hilderink, Lieke J J Klinkenberg, Kristin M Aakre, Norbert C J de Wit, Yvonne M C Henskens, Noreen van der Linden, Otto Bekers, Roger J M W Rennenberg, Richard P Koopmans, Steven J R Meex
BACKGROUND: Middle- and long-term biological variation data for hematological parameters have been reported in the literature. Within-day 24-h variability profiles for hematological parameters are currently lacking. However, comprehensive hour-to-hour variability data are critical to detect diurnal cyclical rhythms, and to take into account the 'time of sample collection' as a possible determinant of natural fluctuation. In this study, we assessed 24-h variation profiles for 20 hematological parameters...
December 21, 2016: Clinical Chemistry and Laboratory Medicine: CCLM
https://www.readbyqxmd.com/read/27995565/a-new-perspective-for-parkinson-s-disease-circadian-rhythm
#19
REVIEW
Siyue Li, Yali Wang, Fen Wang, Li-Fang Hu, Chun-Feng Liu
Circadian rhythm is manifested by the behavioral and physiological changes from day to night, which is controlled by the pacemaker and its regulator. The former is located at the suprachiasmatic nuclei (SCN) in the anterior hypothalamus, while the latter is composed of clock genes present in all tissues. Circadian desynchronization influences normal patterns of day-night rhythms such as sleep and alertness cycles, rest and activity cycles. Parkinson's disease (PD) exhibits diurnal fluctuations. Circadian dysfunction has been observed in PD patients and animal models, which may result in negative consequences to the homeostasis and even exacerbate the disease progression...
December 19, 2016: Neuroscience Bulletin
https://www.readbyqxmd.com/read/27988119/rumination-time-and-reticuloruminal-temperature-as-possible-predictors-of-dystocia-in-dairy-cows
#20
L Kovács, F L Kézér, F Ruff, O Szenci
The objectives of this study were to explore changes of rumination time and reticuloruminal pH and temperature of dairy cows and heifers (means ± standard deviation; age = 5.8 ± 1.9; parity = 2.7 ± 1.4; body condition score = 3.2 ± 0.2) with eutocic (EUT, n = 10) and dystocic calving (DYS, n = 8). The recording period lasted from 3 d before calving until 7 d in milk. For the comparison of rumination time and reticuloruminal characteristics between groups, time to return to baseline (the time interval required to return to baseline from the delivery of the calf) and area under the curve (AUC; both for prepartum and postpartum periods) were calculated for each parameter...
December 14, 2016: Journal of Dairy Science
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