Light Rhythm Research Articles

Misbalance of thyroid hormones after two weeks of exposure to artificial light at night in Eurasian perch Perca fluviatilis.

Artificial light at night (ALAN) can affect the physiology and behavior of animals because it alters the natural rhythm of light and darkness. Thyroid hormones (TH) are partially regulated by the light information of photoperiod and are involved in metabolic adjustments to daily and seasonal changes in the environment, such as larval and juvenile development, somatic growth and reproduction. ALAN can change photoperiodic information and might thereby lead to changes in thyroid metabolism, but so far research on this topic is scarce. Therefore, we tested in two different experiments the effects of nocturnal illumination at a wide range of light intensities on TH in plasma of Eurasian perch (Perca fluviatilis). Total 3,3',5-triiodo-L-thyronine (T3) was significantly affected by ALAN and reduced at the highest tested intensity of 100lx after only two weeks of exposure. Although total L-thyroxine (T4) was not significantly affected, the ratio of T3 to T4 tended to slightly decrease at 100lx. In a second low-light experiment ALAN did not have clear effects on T3, T4 or the ratio of T3 to T4 at intensities between 0.01lx and 1lx. The results show first signs of endocrine disruption in thyroid metabolism after a relatively short ALAN exposure of two weeks under high-intensity streetlight conditions. Misbalanced thyroidal status can have serious implications for metabolic rates as well as developmental and reproductive processes.

ЭЛЕКТРОФИЗИОЛОГИЧЕСКОЕ ИССЛЕДОВАНИЕ ОСЦИЛЛЯТОРНОЙ АКТИВНОСТИ МОЗГА ОБЕЗЬЯН MACACA MULATTA

It is well known that rhythmic light stimulation can alter the electrical activity of the human and animal brain. Moreover, the brain response to certain flicker frequencies significantly exceeds the responses to neighboring frequencies. This phenomenon is thought to be related with the effect of resonance, as evidenced by the coincidence of one of the maxima in the profile of the response to flashes with the frequency of the alpha rhythm. However, other frequencies that cause an increased response to flashes are not reflected in electroencephalogram (EEG) as dominant oscillations. The goal of this study was to reveal the relationship between local maxima in the profile of the responses to flashes of different frequencies and dominant brain oscillations recorded in electrocorticogram (ECoG) of rhesus monkeys without stimulation. The study was carried out on four male Macaca mulatta individuals. In three animals, peak responses were elicited by flickers at 8 and 16 Hz, while one monkey showed a second peak in the 22−30 Hz range. The first maximum (8−10 Hz) in the profile of the response to rhythmic photostimulation coincided with the dominant rhythm recorded in the occipital and parietal regions at rest. The second maximum at 16 Hz coincided with the dominant ECoG rhythm in one of the primates when it was in the state of emotional arousal, which may account for the resonant origin of the increase in responses in this frequency range. The data obtained indicate that dominant brain rhythms, including latent rhythms revealed only by rhythmic photostimulation, can coincide in frequency in monkeys and humans. Neuronal mechanisms of selective sensitivity of neural networks to different frequencies of photostimulation are discussed.

Intermittent Lighting Schedule effects on Broiler Production Performance and Carcass Traits

The current research aim is to examine the impact of light rhythm on development characteristics in broiler chicken before and after slaughter. One hundred and eighty-eight 11-day Ross 308 broilers were picked and reared between 11 to 42 days under an intermittent illumination schedule of either control illumination 6 hours of light: 18 hours of darkness T1 (6L:18D) or 2 hours of light: 2 hours of darkness T2(2L:2D) or 4 hours of light: 4 hours of darkness T3(4L:4D) or 6 hours of light: 6 hours of darkness T3(6L:6D). The results show that there are no significant differences for body weight and body weight gain at 23-42 days and body weight gain at 11-22days of age between treatments, but body weight in intermittent light (2L:2D) was significantly better than control group with other treatments group (P<0.05). The results also demonstrate that here is no significant difference between treatments for feed intake. Use of intermittent lighting schedule improved feed conversion ratio but not significantly (P<0.05). Also for mortality, there is no significant difference between treatments. Similarly, the chest and thigh percentage in birds reared in all photoperiods are not significantly different from each other. In addition, the dressing percentage of birds reared in the (2L:2D) treatment group is greater than measurements observed in the control or other lighting program. Therefore, we can conclude that in broiler managing, the (2L:2D) lighting schedule was preferable compared to 4L:4D, 6L:6D photoperiod and control.

Putative Pacemakers in Crayfish Procambarus clarkii Show Circadian Oscillations in Levels of mRNA for Clock Genes under Different Light Rhythm

In the circadian rhythm mechanism, cycle (Cyc), clock (Clk), cryptochrome (Cry) are three core clock genes that constitute complex mechanism controlling organisms to follow a 24-hour oscillation cycle. In the present study, the major clock genes, i.e. PcCyc, PcClk, PcCry1 were cloned from crayfish Procambarus clarkii. The putative functions as well as physical and chemical properties of the resolved proteins were analyzed by various bioinformatic methods. Real-time quantitative PCR technique was used to explore the mRNA expression of the PcCyc, PcClk, PcCry1 in brain, eyestalk, and hepatopancreas tissues of P. clarkii. In order to examine circadian rhythm of selected clock genes in the species, the experiment was carried out under three different light conditions, namely: (a) 12 h of light and dark periods per day (12LD), (b) 24 h of constant darkness (24DD) and (c) 72 h of constant darkness (72DD). The obtained results showed essential correlation in the mRNA expression levels of PcCyc and PcClk genes under similar light conditions. It indirectly suggests that the PcCYC and PcCLK proteins might be involved in the transcriptomic regulatory mechanism of all other genes within the core-clock network. The mRNA expression levels of the PcCry1 gene were highly variable, differing significantly in relation to the various illumination conditions and sampled tissues. The obtained results seem to follow the pattern evidencing the sensitivity of PcCry1 gene to the light signals. It firmly supports the gene’s role in the conversion mechanism of light signals into optical signals, which is engaged in the generation and control of circadian rhythmicity.

Melatonin Alleviates Glucose and Lipid Metabolism Disorders in Guinea Pigs Caused by Different Artificial Light Rhythms.

Modern lifestyle-associated factors, such as high-calorie intake, high-fat diet (HFD), and excessive artificial light, are risk factors for glucose and lipid metabolism disturbances. Melatonin may be beneficial for managing obesity and diabetes; however, the underlying molecular mechanisms are not well elucidated. We aimed to assess whether melatonin has beneficial effects on constant artificial light-induced fat deposition, lipid metabolism, and insulin resistance. Guinea pigs were randomly divided into five experimental groups: control (C), HFD (H), 12 h light (12HL), 24 h light (24HL), and melatonin (M). The majority of indexes, including insulin resistance and obesity, were measured after 10 weeks. AMP-activated protein kinase α (AMPKα)/peroxisome proliferator-activated receptor-α (PPARα) pathway expression was analyzed by quantitative reverse transcription PCR and western blotting. Although insulin resistance and obesity indexes were higher in the 24HL group than in the 12HL group, they were significantly lower in the M group than in the 24HL group. Melatonin treatment markedly upregulated AMPKα, phosphorylated AMPKα (p-AMPKα), PPARα, and carnitine palmitoyl-CoA transferase 1 A (CPT1A) gene and protein expression. Melatonin may alleviate insulin resistance and obesity caused by persistent artificial light exposure in guinea pigs, likely via activation of the AMPKα/PPARα signaling pathway.

Effect of Electrical Stimulation of Cervical Sympathetic Ganglia on Intraocular Pressure Regulation According to Different Circadian Rhythms in Rats.

PurposeThe purpose of this study was to investigate the relationship between circadian rhythm and intraocular pressure (IOP), and to explore whether electrical stimulation of cervical sympathetic ganglia (SCG) can regulate IOP via neurotransmitter distribution around the Schlemm's canal (SC) in rats.MethodsSprague Dawley rats were housed under normal (N-normal), constant dark (N-dark), and constant light (N-light) rhythms (n = 6 per group). Electrical stimulation (intermittent wave [20 hertz {Hz}, 2 mA, 10 minutes]) was used to stimulate the SCG. Atropine sulfate eye gel was applied three times a day. DiI was injected into the SCG and anterior chamber. The cross-sectional area and circumference of SC were evaluated using hematoxylin-eosin staining. Immunofluorescence staining was used to evaluate dopamine-β-hydroxylase (DβH) expression in SC endothelial (SCE) cells.ResultsN-Dark increased the IOP, decreased the cross-sectional area of SC, and increased DβH levels in SCE cells. Nerve projection between SC and SCG was detected, and electrical stimulation of SCG upregulated DβH expression in SCE cells. Under normal and constant light rhythms, electrical stimulation of SCG increased DβH and decreased the cross-sectional area and circumference of SC, while simultaneously increasing IOP and decreasing IOP fluctuations. After paralyzing the ciliary muscles, electrical stimulation of SCG decreased the cross-sectional area and circumference of SC under normal and constant light rhythms.ConclusionsN-Dark increased DβH in SCE cells, reduced the cross-sectional area of SC, and increased IOP. Under the normal and light rhythms, electrical stimulation of SCG increased DβH in SCE cells, reduced the cross-sectional area and circumference of SC, and in turn elevated IOP and decreased IOP fluctuations.

Discharge and Role of GABA Pontomesencephalic Neurons in Cortical Activity and Sleep-Wake States Examined by Optogenetics and Juxtacellular Recordings in Mice.

The cholinergic neurons in the pontomesencephalic tegmentum have been shown to discharge in association with and promote cortical activation during active or attentive waking and paradoxical or rapid eye movement sleep. However, GABA neurons lie intermingled with the cholinergic neurons and may contribute to or oppose this activity and role. Here we investigated in vitro and in vivo the properties, activities, and role of GABA neurons within the laterodorsal tegmental and sublaterodorsal tegmental nuclei (LDT/SubLDT) using male and female transgenic mice expressing channelrhodopsin-(ChR2)-EYFP in vesicular GABA transporter (VGAT)-expressing neurons. Presumed GABA (pGABA) neurons were identified by response to photostimulation and verified by immunohistochemical staining following juxtacellular labeling in vivo pGABA neurons were found to be fast-firing neurons with the capacity to burst when depolarized from a hyperpolarized membrane potential. When stimulated in vivo in urethane-anesthetized or unanesthetized mice, the pGABA neurons fired repetitively at relatively fast rates (∼40 Hz) during a continuous light pulse or phasically in bursts (>100 Hz) when driven by rhythmic light pulses at theta (4 or 8 Hz) frequencies. pNon-GABA, which likely included cholinergic, neurons were inhibited during each light pulse to discharge rhythmically in antiphase to the pGABA neurons. The reciprocal rhythmic bursting by the pGABA and pNon-GABA neurons drove rhythmic theta activity in the EEG. Such phasic bursting by GABA neurons also occurred in WT mice in association with theta activity during attentive waking and paradoxical sleep.SIGNIFICANCE STATEMENT Neurons in the pontomesencephalic tegmentum, particularly cholinergic neurons, play an important role in cortical activation, which occurs during active or attentive waking and paradoxical or rapid eye movement sleep. Yet the cholinergic neurons lie intermingled with GABA neurons, which could play a similar or opposing role. Optogenetic stimulation and recording of these GABA neurons in mice revealed that they can discharge in rhythmic bursts at theta frequencies and drive theta activity in limbic cortex. Such phasic burst firing also occurs during natural attentive waking and paradoxical sleep in association with theta activity and could serve to enhance sensory-motor processing and memory consolidation during these states.

Linking Light-Dependent Life History Traits with Population Dynamics for Prochlorococcus and Cyanophage

ABSTRACTProchlorococcus cyanobacteria grow in diurnal rhythms driven by diel cycles. Their ecology depends on light, nutrients, and top-down mortality processes, including lysis by viruses. Cyanophage, viruses that infect cyanobacteria, are also impacted by light. For example, the extracellular viability and intracellular infection kinetics of some cyanophage vary between light and dark conditions. Nonetheless, it remains unclear whether light-dependent viral life history traits scale up to influence population-level dynamics. Here, we examined the impact of diel forcing on both cellular- and population-scale dynamics in multiple Prochlorococcus-phage systems. To do so, we developed a light-driven population model, including both cellular growth and viral infection dynamics. We then tested the model against measurements of experimental infection dynamics with diel forcing to examine the extent to which population level changes in both viral and host abundances could be explained by light-dependent life history traits. Model-data integration reveals that light-dependent adsorption can improve fits to population dynamics for some virus-host pairs. However, light-dependent variation alone does not fully explain realized host and virus population dynamics. Instead, we show evidence consistent with lysis saturation at relatively high virus-to-cell ratios. Altogether, our study represents a quantitative approach to integrate mechanistic models to reconcile Prochlorococcus-virus dynamics spanning cellular-to-population scales.IMPORTANCE The cyanobacterium Prochlorococcus is an essential member of global ocean ecosystems. Light rhythms drive Prochlorococcus photosynthesis, ecology, and interactions with potentially lethal viruses. At present, the impact of light on Prochlorococcus-virus interactions is not well understood. Here, we analyzed Prochlorococcus and virus population dynamics with a light-driven population model and compared our results with experimental data. Our approach revealed that light profoundly drives both cellular- and population-level dynamics for some host-virus systems. However, we also found that additional mechanisms, including lysis saturation, are required to explain observed host-virus dynamics at the population scale. This study provides the basis for future work to understand the intertwined fates of Prochlorococcus and associated viruses in the surface ocean.

Disrupted Glutamate Signaling in Drosophila Generates Locomotor Rhythms in Constant Light

We have used the Cambridge Protein Trap resource (CPTI) to screen for flies whose locomotor rhythms are rhythmic in constant light (LL) as a means of identifying circadian photoreception genes. From the screen of ∼150 CPTI lines, we obtained seven hits, two of which targeted the glutamate pathway, Got1 (Glutamate oxaloacetate transaminase 1) and Gs2 (Glutamine synthetase 2). We focused on these by employing available mutants and observed that variants of these genes also showed high levels of LL rhythmicity compared with controls. It was also clear that the genetic background was important with a strong interaction observed with the common and naturally occurring timeless (tim) polymorphisms, ls-tim and s-tim. The less circadian photosensitive ls-tim allele generated high levels of LL rhythmicity in combination with Got1 or Gs2, even though ls-tim and s-tim alleles do not, by themselves, generate the LL phenotype. The use of dsRNAi for both genes as well as for Gad (Glutamic acid decarboxylase) and the metabotropic glutamate receptor DmGluRA driven by clock gene promoters also revealed high levels of LL rhythmicity compared to controls. It is clear that the glutamate pathway is heavily implicated in circadian photoreception. TIM levels in Got1 and Gs2 mutants cycled and were more abundant than in controls under LL. Got1 but not Gs2 mutants showed diminished phase shifts to 10 min light pulses. Neurogenetic dissection of the LL rhythmic phenotype using the gal4/gal80 UAS bipartite system suggested that the more dorsal CRY-negative clock neurons, DNs and LNds were responsible for the LL phenotype. Immunocytochemistry using the CPTI YFP tagged insertions for the two genes revealed that the DN1s but not the DN2 and DN3s expressed Got1 and Gs2, but expression was also observed in the lateral neurons, the LNds and s-LNvs. Expression of both genes was also found in neuroglia. However, downregulation of glial Gs2 and Got1 using repo-gal4 did not generate high levels of LL rhythmicity, so it is unlikely that this phenotype is mediated by glial expression. Our results suggest a model whereby the DN1s and possibly CRY-negative LNds use glutamate signaling to supress the pacemaker s-LNvs in LL.

Can skyglow reduce nocturnal melatonin concentrations in Eurasian perch?

Artificial light at night (ALAN) changes the natural rhythm of light and darkness and can impair the biorhythms of animals, for example the nocturnal melatonin production of vertebrates, which serves as a proxy for daily physiological rhythms. Freshwater fish are exposed to ALAN in large urban and suburban areas in the form of direct light or in the form of skyglow, a diffuse brightening of the night sky through the scattered light reflected by clouds, atmospheric molecules, and particles in the air. However, investigations on the sensitivity of melatonin production of fish towards low intensities of ALAN in the range of typical skyglow are rare. Therefore, we exposed Eurasian perch (Perca fluviatilis) to nocturnal illumination levels of 0.01 lx, 0.1 lx and 1 lx and a control group with dark nights and daylight intensities of 2900 lx in all groups. After ten days of exposure to the experimental conditions, tank water was non-invasively sampled every 3 h over a 24 h period and melatonin was measured by ELISA. Melatonin was gradually reduced in all treatments with increasing intensity of ALAN whereas rhythmicity was maintained in all treatment groups although at 1 lx not all evaluated parameters confirmed rhythmicity. These results show a high sensitivity of Eurasian perch towards ALAN indicating that low light intensities of 0.01 lx and 0.1 lx as they occur in urban and suburban areas in the form of skyglow can affect the physiology of Eurasian perch. Furthermore, we highlight how this may impact perch in their sensitivity towards lunar rhythms and the role of skyglow for biorhythms of temperate freshwater fish.

Melatonin Orchestrates Lipid Homeostasis through the Hepatointestinal Circadian Clock and Microbiota during Constant Light Exposure.

Misalignment between natural light rhythm and modern life activities induces disruption of the circadian rhythm. It is mainly evident that light at night (LAN) interferes with the human endocrine system and contributes to the increasing rates of obesity and lipid metabolic disease. Maintaining hepatointestinal circadian homeostasis is vital for improving lipid homeostasis. Melatonin is a chronobiotic substance that plays a main role in stabilizing bodily rhythm and has shown beneficial effects in protecting against obesity. Based on the dual effect of circadian rhythm regulation and antiobesity, we tested the effect of melatonin in mice under constant light exposure. Exposure to 24-h constant light (LL) increased weight and insulin resistance compared with those of the control group (12-h light–12-h dark cycle, LD), and simultaneous supplementation in the melatonin group (LLM) ameliorated this phenotype. Constant light exposure disturbed the expression pattern of a series of transcripts, including lipid metabolism, circadian regulation and nuclear receptors in the liver. Melatonin also showed beneficial effects in improving lipid metabolism and circadian rhythm homeostasis. Furthermore, the LL group had increased absorption and digestion of lipids in the intestine as evidenced by the elevated influx of lipids in the duodenum and decrease in the efflux of lipids in the jejunum. More interestingly, melatonin ameliorated the gut microbiota dysbiosis and improved lipid efflux from the intestine. Thus, these findings offer a novel clue regarding the obesity-promoting effect attributed to LAN and suggest a possibility for obesity therapy by melatonin in which melatonin could ameliorate rhythm disorder and intestinal dysbiosis.

The role of natural light rhythm in the development of desynchronosis in the conditions of rotational shiftwork in the Arctic

Purpose. To study the effects of a natural light cycle on circadian rhythms of blood pressure (BP) and heart rate conditions of rotational shiftwork in the Far North. Material and Methods . Data of 24-h BP monitoring were analyzed in 373 male patients with hypertension stage II monthly round-trip sojourns to the Arctic compared with a similar group of 144 patients living in moderate climate (Tyumen, 57 N). The standard and chronobiological parameters of 24-h BP monitoring were analyzed in 93 randomly selected patients of the Far North group and 64 patients of the Tyumen group. The 24-h BP profile, circadian indices of systolic and diastolic BP, percentage contribution value, rhythm amplitude, acrophase, and diurnal mean value of 24-h BP rhythm were studied during the seasons of the year. Results. The circadian rhythms of HR and BP in hypertensive patients in the conditions of rotational shiftwork in the Arctic showed the signs of internal desynchronosis and significantly differed from those in Tyumen patients independently of a season. The lack of natural light in the Far North during the polar day and polar night resulted in the flattened curves of circadian BP and HR rhythms in the hypertensive patients. Other major differences consisted in the low-amplitude profile of the spectrum and the loss of 24-h component in this group. The seasonal changes in HR in the comparison group were insignificant unlike those in the Far North group, which showed maximum flattening of HR rhythm during the polar day and polar night. Winter season (polar night) was the most adverse for the main group of patients in regard to their 24-h BP profile, which was characterized by the maximum degree of circadian rhythm flattening and the predominance of high-frequency oscillations in the spectrum. Conclusions. The development of circadian and seasonal desynchronosis of the HR and BP rhythms in hypertensive patients in the conditions of rotational shiftwork in the Arctic was caused not only by the labour characteristics and the climatic factors, but also by the natural light rhythmicity in the high latitude.

CRITICAL FREQUENCY OF FLICKER MERGING AND VISUAL POTENTIALS UNDER COMPUTER LOAD

The urgency of the development and improvement of methods for studying the functional state of users of computer technology is growing in parallel with the growth of their negative impact on the main targets - visual and neuropsychic functions. Therefore, the aim of the study was to study the processes of perception of rhythmic light incentives and induced electrical activity of the visual cortex during a computer load. The study was conducted with the participation of clinically healthy students ( n = 182), who determined the critical fusion frequency of flashes and recorded rhythmic cortical evoked visual potentials during a computer-assisted visual load. To assess the nature and duration of use of computer students, as well as determining the presence and severity of computer dependency, a survey was conducted. Various types of perception of light flashes and changes in the rhythm assimilation reaction under the influence of a computer load are revealed. The data are discussed taking into account the rhythmic processes of the brain. A conclusion is drawn about the weakened, stable and strengthened types of response of oscillatory neural mechanisms to computer visual loads.

Expressive Motion in the Early Films of Mary Ellen Bute

Between 1935 and 1938, Mary Ellen Bute began her career as a filmmaker with a series of mostly animated films, including Rhythm in Light (1935), Synchromy No. 2 (1936), Parabola (1938) and Escape (1938). This article examines how these films offered an innovative, subtle and purposeful investigation of the potentials of animation to create artistic and expressive motion. Paying close attention to Bute’s own writing, the article explores how these films related to Bute’s expansive vision of cinema as a new form of kinetic art that was both composed and free-flowing. Drawing upon painting, music, sculpture and chronophotography, Bute’s work was highly intermedial, investing these arts and media with the dynamic potentials of filmic and animated motion. Tracing how Bute composed motion, displayed motion and used motion expressively, this article aims to develop our understanding of a pivotal 20th-century filmmaker, while at the same time investigating the distinctive ideas of the aesthetics, forms and effects of animated motion that were articulated in her filmmaking practice and theoretical writing.

Human Electroencephalogram-Controlled Effects of Photostimulation

The assumption that rhythmic light stimulation may exhibit high biological efficiency when automatically modulated by a human electroencephalogram has been tested experimentally. A comparative analysis of the effects observed in the same subjects in response to the two types of rhythmic photostimulation has been performed. In one case, 15 volunteers who were in a state of stress and anxiety, were exposed to real-time light rhythmic stimulation based on their electroencephalograms, and in the other case (control), rhythmic photostimulation was applied at a frequency that increased linearly from 4 to 25 Hz. It has been demonstrated that significant positive shifts in the objective and subjective indicators are found only in cases when the control of light stimulation is performed directly via the subject’s electroencephalogram. These results may be explained by an increased personalization of electroencephalogram-derived stimulation, as well as by the the interaction between the interoceptive signals with the resonance mechanisms of the brain, which provide the normalization of the human functional state under electroencephalogram-derived rhythmic light stimulation.

Early ambulation after femoral percutaneous transluminal angioplasty - report of 02 cases

INTRODUCTION: In Brazil and around the world, there is still an abundance of hospital services that restrict exercise in individuals undergoing percutaneous coronary interventions (PCI), in the immediate postoperative period, for fear of complications. It is important to demonstrate that cardiovascular physical therapy can be performed in this population. OBJECTIVE: To verify the adverse effects in the performance of early ambulation after PCI, with the use of a mechanical device of arterial closure in the femoral puncture. POPULATION AND METHODS: Two cases (68-years-old man and 57-years-old woman) submitted to a single-vessel coronary artery (right coronary artery and diagonal branch, respectively) that had their femoral puncture associated with the device Angio-Seal - St. Jude Medical©, who were discharged from the hospital six hours after the intervention. Before PCI, patients had stable angina and cardiovascular risk factors (dyslipidemia, hypertension, and others). After the PCI, the patients were evaluated by the Heart Team, who monitored intercurrences during hospitalization (chest pain, ventilatory discomfort, electrocardiogram, cardiac enzymes and others). The gait of the individuals was verified, in order to evaluate the tolerance of the individuals to the same, after five hours of the PCI. Individuals were advised to walk in a light rhythm (modified Borg 1-3) for five minutes in a corridor of approximately 15 meters, in round-trip movements, and were evaluated after ambulation for hematoma at the puncture site, pain or any complications that might arise. On the first postoperative day, a telephone call was made for a second complication check. RESULTS: Both patients tolerated the five-minute walk and were released from the hospital after six hours, wandering uneventfully. One of the patients reported low-intensity headache during hospitalization. The same patient reported low-intensity pain at the puncture site the next day. There were no clinically relevant changes in cardiovascular or ventilatory parameters during the six hours postoperative hospitalization or during ambulation. CONCLUSION: Early ambulation within six hours after PCI was well tolerated in the two cases studied, even with the femoral artery access site. The use of a mechanical device for arterial closure was important so that the ambulation could be carried out in this population.

The national nature of Vitaism and Vasily Barvinsky

The article raises the problem of one of the dimensions of national modernism in the first half of the twentieth century – Vitaism, which is manifested not only in literature, but also other forms of art, in particular, music. The synthetic nature of Vitaism, the platform of which was outlined by M. Khvylovy, answered the aesthetic requests of the development of the new Ukrainian culture at that time and proved to be in agreement with many of its representatives. Acting in correspondence with the artists of the Dnieper Ukraine, professing the ideas of the uniqueness and unity of Ukrainianness, V. Barvinsky showed vivid and vibrant vitaistic tendencies in his work The nation-building idea gathers and absorbs all the life processes of the artist, revealing deep mental roots as the basis of vitaism - the heart animation of life. The fusion of ethnogenetic origin (through intense folklorizm) with a historical tradition (broad national and European temporal perspective) occurs at the composer under the denominator of cordocentric lyrical, however, active romanticism. Numerous vectors of neo- (baroque, classicism, romanticism) as one of the centrifugal axes of V. Barvinsky's style, opens a new round of vision and renewal of tradition. Along with the bright, solid pages of the composer's music, there is also a tangible tragedy. Responsible "heart-universe" does not avoid darkness, because light and darkness are in the only indivisible heart of a person, who is responsible for the dark first, too, grasping the antithetical and contradictory life. The main method of the artist is the desire for synaesthetic fusion in the sound matter of play, plasticity, color, symbol and movement (light rhythm). Conceptual modeling based on such a synthesis gives unique Ukrainian pictures of our own poetic image of the world. The rationalism of Vitaism was manifested in the high education and professionalism of the artist, who called for responsibility for the need to build a serious national cultural school, which served as a voluminous critical journalistic and scientific-pedagogical activity. Barvinsky, as one of the central figures of Galician musical culture of the first half of the twentieth century, reveals an original and unique synthesis of the tendencies of numerous artistic and aesthetic directions of the day. However, the optic ideological axis and active romanticism that shape the composer's stylistic dominance, vital conceptualism in the artistic modeling of the artist's world, make V. Barvinsky one of the brightest representatives of Vitaism.

Influence of rhythmic light stimulation on orientation signal within visual cortex columns in the cat

The present study used optical imaging to investigate the development of the optical signal within orientational columns in primary visual cortex of cats reared under conditions of rhythmic light stimulation. Results showed that, although inter-columnar spacing was unchanged, a 3-5-fold decrement in optical signal from orientation columns and a drastic decline in contrast sensitivity was observed in both areas 18 and 17. These data suggest the modification of cortical columnar functioning under artificially correlated synchronization of retinal input.

Discharge and Role of Acetylcholine Pontomesencephalic Neurons in Cortical Activity and Sleep-Wake States Examined by Optogenetics and Juxtacellular Recording in Mice.

Acetylcholine (ACh) neurons in the pontomesencephalic tegmentum (PMT) are thought to play an important role in promoting cortical activation with waking (W) and paradoxical sleep [PS; or rapid eye movement (REM)], but have yet to be proven to do so by selective stimulation and simultaneous recording of identified ACh neurons. Here, we employed optogenetics combined with juxtacellular recording and labeling of neurons in transgenic (TG) mice expressing ChR2 in choline acetyltransferase (ChAT)-synthesizing neurons. We established in vitro then in vivo in anesthetized (A) and unanesthetized (UA), head-fixed mice that photostimulation elicited a spike with short latency in neurons which could be identified by immunohistochemical staining as ACh neurons within the laterodorsal (LDT)/sublaterodorsal (SubLDT) and pedunculopontine tegmental (PPT) nuclei. Continuous light pulse stimulation during sleep evoked tonic spiking by ACh neurons that elicited a shift from irregular slow wave activity to rhythmic θ and enhanced γ activity on the cortex without behavioral arousal. With θ frequency rhythmic light pulse stimulation, ACh neurons discharged in bursts that occurred in synchrony with evoked cortical θ. During natural sleep-wake states, they were virtually silent during slow wave sleep (SWS), discharged in bursts during PS and discharged tonically during W. Yet, their bursting during PS was not rhythmic or synchronized with cortical θ but associated with phasic whisker movements. We conclude that ACh PMT neurons promote θ and γ cortical activity during W and PS by their tonic or phasic discharge through release of ACh onto local neurons within the PMT and/or more distant targets in the hypothalamus and thalamus.

Development of the Astyanax mexicanus circadian clock and non-visual light responses

Most animals and plants live on the planet exposed to periods of rhythmic light and dark. As such, they have evolved endogenous circadian clocks to regulate their physiology rhythmically, and non-visual light detection mechanisms to set the clock to the environmental light-dark cycle. In the case of fish, circadian pacemakers are not only present in the majority of tissues and cells, but these tissues are themselves directly light-sensitive, expressing a wide range of opsin photopigments. This broad non-visual light sensitivity exists to set the clock, but also impacts a wide range of fundamental cell biological processes, such as DNA repair regulation. In this context, Astyanax mexicanus is a very intriguing model system with which to explore non-visual light detection and circadian clock function. Previous work has shown that surface fish possess the same directly light entrainable circadian clocks, described above. The same is true for cave strains of Astyanax in the laboratory, though no daily rhythms have been observed under natural dark conditions in Mexico. There are, however, clear alterations in the cave strain light response and changes to the circadian clock, with a difference in phase of peak gene expression and a reduction in amplitude. In this study, we expand these early observations by exploring the development of non-visual light sensitivity and clock function between surface and cave populations. When does the circadian pacemaker begin to oscillate during development, and are there differences between the various strains? Is the difference in acute light sensitivity, seen in adults, apparent from the earliest stages of development? Our results show that both cave and surface populations must experience daily light exposure to establish a larval gene expression rhythm. These oscillations begin early, around the third day of development in all strains, but gene expression rhythms show a significantly higher amplitude in surface fish larvae. In addition, the light induction of clock genes is developmentally delayed in cave populations. Zebrafish embryonic light sensitivity has been shown to be critical not only for clock entrainment, but also for transcriptional activation of DNA repair processes. Similar downstream transcriptional responses to light also occur in Astyanax. Interestingly, the establishment of the adult timing profile of clock gene expression takes several days to become apparent. This fact may provide mechanistic insight into the key differences between the cave and surface fish clock mechanisms.