Single, high doses of TCDD in rats are known to cause wasting, a progressive loss of 30 to 50% body weight and death within several weeks. To identify pathway perturbations at or near doses causing ...wasting, we examined differentially gene expression (DGE) and pathway enrichment in centrilobular (CL) and periportal (PP) regions of female rat livers following 6 dose levels of TCDD – 0, 3, 22, 100, 300, and 1000 ng/kg/day, 5 days/week for 4 weeks. At the higher doses, rats lost weight, had increased liver/body weight ratios and nearly complete cessation of liver cell proliferation, signs consistent with wasting. DGE curves were left shifted for the CL versus the PP regions. Canonical Phase I and Phase II genes were maximally increased at lower doses and remained elevated at all doses. At lower doses, ≤ 22 ng/kg/day in the CL and ≤ 100 ng/kg/day, upregulated genes showed transcription factor (TF) enrichment for AHR and ARNT. At the mid- and high-dose doses, there was a large number of downregulated genes and pathway enrichment for DEGs which showed downregulation of many cellular metabolism processes including those for steroids, fatty acid metabolism, pyruvate metabolism and citric acid cycle. There was significant TF enrichment of the hi-dose downregulated genes for RXR, ESR1, LXR, PPARalpha. At the highest dose, there was also pathway enrichment with upregulated genes for extracellular matrix organization, collagen formation, hemostasis and innate immune system. TCDD demonstrates most of its effects through binding the aryl hydrocarbon receptor (AHR) while the downregulation of metabolism genes at higher TCDD doses is known to be independent of AHR binding to DREs. Based on our results with DEG, we provide a hypothesis for wasting in which high doses of TCDD shift circadian processes away from the resting state, leading to greatly reduced synthesis of steroids and complex lipids needed for cell growth, and producing gene expression signals consistent with an epithelial-to-mesenchymal transition in hepatocytes.
•In life studies in female rats with TCDD produce wasting-like responses within 4 weeks•Low doses upregulate genes regulated by AHR and ARNT; higher doses downregulate genes for cellular metabolism.•Downregulated genes at high doses are enriched for TF-binding sites for RXR, LXR, PPARA and ESR1.•Very high doses downregulated metabolic processes and upregulated those for extracellular matrix.•Wasting is most likely associated with sequestration of AHR and ARNT that removes them from roles in circadian cycling.
To investigate potential differences in discharge time, feeding methods and amounts, daily weight gain, vital signs, pain, and comfort levels among preterm infants born at 28–32 weeks' gestation who ...were hospitalized in the neonatal intensive care unit during long-term follow-up while implementing a light-dark cycle.
This is a randomized controlled study conducted with the support of a day-night cycle in premature infants born at 28–32 weeks' gestation and admitted to the neonatal intensive care unit of a teaching and research hospital affiliated with the Ministry of Health. The study compared the follow-up results from hospitalization to discharge over a period of 8 weeks.
50% of premature infants admitted to the unit are multiple pregnancies. There was no significant difference in discharge weight, comfort level, pain level, vital signs of the infants included in the study (p > 0.05). The optimal development of infant feeding patterns was examinedand it was observed that the study group had significantly improved before the control group in terms of the time to switch to full enteral feeding and oral feeding (p < 0,05). The daily weight gain of the babies was examined, it was seen that the weight gain was higher in the study group compared to the control group (p < 0,05). The mean duration of hospitalization was compared, it was seen that the babies in the study group were discharged significantly earlier (p < 0,05).
The study compared the long-term outcomes of premature babies hospitalized in neonatal intensive care and babies exposed to a light-dark cycle and regularly monitored in standard care. The results showed that the babies in the study group had higher daily weight gain and were discharged earlier than the control group. There were also no statistically significant differences in comfort and pain scores, vital signs or oxygen saturation between the study and control groups.
A light-dark cycle was found to be a feasible and promising intervention for infants at 28–32 weeks' gestation. It was a nurse-led management of care that could be integrated into the usual care of 28–32-week-old babies in neonatal units.
Shift work has become a necessity in many industries; however, the shift work system disrupts the endogenous circadian rhythm by changing the sleep-wake cycle and can prepare the ground for ...cardiovascular diseases. Shift workers are at risk of some chronic disorders such as hypertension, elevated serum lipids and body weight, cardiovascular conditions, including coronary artery disease, acute myocardial infarction, and stroke and metabolic syndrome. Furthermore, it is thought that changes occur in the concentrations of melatonin, cortisol, ghrelin, and leptin due to the night shift work, and this is associated with the change in the circadian rhythm. In this condition, reconsidering some precautions can reduce the risk of cardiovascular disease. Recently, it has been shown that exercise can be effective in reducing the risk of cardiovascular disease in shift workers. The aim of this review is to determine the relationship with cardiovascular diseases and shift work system.
Plants of the Amaryllidaceae family have been used as therapeutic agents against CNS related maladies such as Alzheimer′s disease. The known primary alkaloid constituents have significant biological ...activity. We identified the Lycoris alkaloids lycorine and lycoricidinol from Amaryllidaceae using a real-time reporter gene assay system based on NIH3T3 cells. These alkaloids have a wide spectrum of pharmacological actions and dose-dependently lengthen the circadian period. When cells that had been incubated with lycorine or lycoricidinol were washed and then incubated without these alkaloids, period length reverted to that of control cells, suggesting that elongation of the circadian period induced by lycorine and lycoricidinol is reversible. Although one of its major activities is the inhibition of protein synthesis, lycorine induced dose-dependent period elongation regardless of the presence of cycloheximide and moreover, cycloheximide, itself did not affect period length, suggesting that lycorine dose-dependently extends the circadian period by a mechanism other than translational inhibition. Real-time RT-PCR showed that lycorine enhanced RORα and Bmal1 transcription, and exogenous expression and knockdown of Bmal1 also caused long and short periods, respectively, thus confirming the phenotype indicated by lycorine. These data indicate that lycorine and lycoricidinol modulate Bmal1 transcription and the circadian period, and also suggest that Lycoris alkaloids are novel contributors to the control of period length in mammalian cells.
Endogenous circadian rhythms observed under constant conditions normally show period length variations. However, a general trend is difficult to identify when cells or organisms are entrained with ...the usual 24-h-period light/dark cycles. Therefore, these variations in time have been considered as fluctuations. In order to gain more insight into this phenomenon, individual Acetabularia cells were exposed to light/dark cycles of 16 h (LD 8:8) and 33.6 h (LD 16.8:16.8), respectively, i.e., periods which lie distinctly outside the range of the normal circadian entrainment. Employing a high-resolution procedure for data analysis, decreasing period lengths could consistently be detected when cells were kept under constant conditions for several weeks. Possible causes of this decrease are discussed.
System of Comfortable Live Level Improvement Zheliazkov, Yehor; Globa, Larysa; Yamnenko, Iuliia
2023 International Conference on Information and Digital Technologies (IDT),
2023-June-22
Conference Proceeding
Connection between physical systems and human is an essential task in man-machine systems. Comfort level is an essential element that has considerable impact on human Self-Esteem, related to human ...circadian rhytms and the perception of the environments. Nowadays issues of comfortable level improvement is still actual, because of the current research in this direction don't take into account the physiological characteristics of individual. The paper deals with the \text{IoT} system development, that based on the individual physiological characteristics. For this the \text{IoT} system uses the circadian rhytms analysis for indoor comfort level control by sensors. Light can be used not only in terms of the human visual system, but also for effecting to the circadian system. Each of the microclimate parameters has got a direct impact on comfortable level at the certain period of time: room or radiation temperature, humidity, lighting, speed and direction of the wind, etc. The paper describes the new system, which helps to older people with a comfortable level and healthcare. The relation between circadian rhythms and indoor parameters were studied based on real experiments. The results of this experiment allow to elaborate smart \text{IoT} system that is able to adapt to human perception of microclimate parameters, circadian rhythms and also can even rescue somebody's life.
Impact of lighting parameters on human comfortable feeling Zheliazkov, Yehor; Yamnenko, Julia
2022 IEEE 63th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON),
2022-Oct.-10
Conference Proceeding
Comfortable level is an essential element that has considerable implications on human circadian rhytms and the perception of the environments. Light has been defined only in terms of the human visual ...system, not the circadian system. Light parameters should consider the needs of both the visual and non-visual systems. Discussed are the lighting characteristics impacting these two systems and the implications for designing light for various healthcare and medical applications. The paper describes the experiment conducted in climate chamber of Dresden technical university. The results of this experiment allow to elaborate smart lighting control system that is able to adjust to human perception and circadian rhytms.
Several authors have suggested that Dexamethasone Suppression Test (DST) non-suppression is related to circadian alternations of hypothalamic-pituitary-adrenal function. Two clinical manifestations ...of altered circadian rhythms in depressed patients are early morning awakening and diurnal variation in mood. To observe whether these clinical symptom patterns were associated with an increased frequency of abnormal DSTs, we examined post-DST plasma cortisol concentrations and matched clinical ratings of early morning awakening and diurnal variation in mood in 49 patients with major depressive disorder, endogenous subtype. We found no significant association between these clinical and laboratory variables.
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