scholarly journals Extra Visual Function of the Human Eye.

2020 ◽  
pp. 1-6
Keyword(s):  
Biological Clock ◽  
Biological Rhythms ◽  
Visual Image ◽  
Photochemical Activity ◽  
Electrical Signal ◽  
The Body ◽  
Scotopic Vision ◽  
Rods And Cones ◽  
Organ Systems ◽  
The Brain

Abstract The eye is part of the sensory nervous system. However, there are a number of organ systems that also work with the eye. The retina is the only tissue in mammals that regulates photoreception due to the presence of photoreceptors, the rods and cones and performs both visual and non-visual functions Light plays a fundamental role in the behavior of almost all organisms. In addition to visual processes, light also induces important physiological responses. People with mild vascular disease that causes damage to the retina in the eye are more likely to have problems with thinking and memory skills. Everyone has a natural body clock that they are born with and all organs in the body operate according to biological rhythms. Our experiments with ophthalmic mutant rats also showed that the loss of vision also hampered their physiological activities and their rhythmicity was also disturbed. The menstrual cycle disturbances and age of menarche are regulated by many factors; nevertheless, blindness is one of the most impotent factors in regulating biological clock dependent functions. The human eyes are the only organs in the body capable of “seeing”- wavelengths of light and turning it into visual images. We can't “see” or get a visual image to the brain without eyes. The eye-like ability of skin to sense light by using a receptor (Cryptochrome) but failed to form image. Photoreceptors contain chemicals that change when they are hit by light. This causes an electrical signal, which is then sent to the brain along the optic nerve. Different types of photoreceptor allow us to see an enormous range of light and colours. There are two types of photoreceptors in the human retina, rods and cones. Rods are responsible for vision at low light levels (scotopic vision). They do not mediate colour vision and have a low spatial acuity. The blind: People who have lost their sight have different experiences. Some describe seeing complete darkness, like being in a cave. Some people see sparks or experience vivid visual hallucinations that may take the form of recognizable shapes, random shapes and colours, or flashes of light. An afterimage is an image that continues to appear in the eyes after a period of exposure to the original image. Afterimages occur because photochemical activity in the retina continues even when the eyes are no longer experiencing the original stimulus.

Corticotrophin Releasing Hormone: Chemistry and Recent Developments

2004 ◽  
Vol 57 (5) ◽  
pp. 393 ◽  
Author(s):  
James Garner ◽  
Paul A. Keller ◽  
Adam McCluskey
Keyword(s):  
Neurological Disorders ◽  
Biological Clock ◽  
The Body ◽  
Exciting Field ◽  
Releasing Hormone ◽  
The Past ◽  
Corticotrophin Releasing Factor ◽  
Recent Developments ◽  
Fight Or Flight Response ◽  
The Brain

Corticotrophin Releasing Hormone [CRH; also known as Corticotrophin Releasing Factor (CRF)], a 41-amino-acid hormone, is one of the body’ major modulators of the stress response. CRH coordinates the endocrine, autonomic, and behavioural responses to stress through actions in both the brain and the periphery activating the ‘fight or flight’ response. CRH is also implicated in various neurological disorders including Alzheimer’s, Parkinson’s, and anorexia nervosa, and it has been described as a biological clock controlling the length of gestation in humans and other higher-order primates. In the past decade there has been an enormous effort expended in the design and development of new therapeutic agents targetting CRHs in the central nervous and peripheral systems. In this review, we examine the chemistry and recent developments in this exciting field.

scholarly journals Ophthalmology: ozone therapy applied to dystrophic maculopathy

Ozone Therapy ◽  
2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Giorgio Grechi
Keyword(s):  
The Body ◽  
Age Related Macular Degeneration ◽  
Antioxidant Systems ◽  
Macular Area ◽  
Ozone Therapy ◽  
Rods And Cones ◽  
Age Related ◽  
Small Structure ◽  
Colloid Cysts ◽  
The Brain

The macula, which is the noblest part of the retina, is a very small structure, containing the photoreceptors (rods and cones) responsible for visual acuity. Over the years, observations have confirmed that alterations that modify the optimal state of the eye also give rise to similar diseases in the brain: ischemias, structural circulatory alterations and neurodegeneration. As the body ages, oxidative alterations take place and they change the antioxidant systems that serves as a neurological and ocular defence. In industrialised nations, age-related macular degeneration is the leading cause of blindness in patients over 55 years of age. Initially, this creates drusen (or colloid cysts) in the macular area.

scholarly journals In situ localization of the per clock protein during development of Drosophila melanogaster.

1988 ◽  
Vol 8 (12) ◽  
pp. 5378-5385 ◽  
Author(s):  
L Saez ◽  
M W Young
Keyword(s):  
Drosophila Melanogaster ◽  
Biological Clock ◽  
Biological Rhythms ◽  
Adult Brain ◽  
Genetic Studies ◽  
Ring Gland ◽  
Ultradian Rhythmicity ◽  
The Brain ◽  
Clock Protein

The per locus influences biological rhythms in Drosophila melanogaster. In this study, per transcripts and proteins were localized in situ in pupae and adults. Earlier genetic studies have demonstrated that per expression is required in the brain for circadian locomotor activity rhythms and in the thorax for ultradian rhythmicity of the Drosophila courtship song. per RNA and proteins were detected in a restricted group of cells in the eyes and optic lobes of the adult brain and in many cell bodies in the adult and pupal thoracic ganglia. per products were also found in the pupal ring gland complex, a tissue involved in rhythmic aspects of Drosophila development. Abundant expression was seen in gonadal tissue. No biological clock phenotypes have been reported for this tissue in any of the per mutants, per protein mapped to different subcellular locations in different tissues. The protein accumulated in or around nuclei in some cells and appeared to be cytoplasmic in others.

Experimental study of irreversible shock and the brain

1973 ◽  
Vol 39 (4) ◽  
pp. 434-441 ◽  
Author(s):  
Patrick F. Golden ◽  
John A. Jane
Keyword(s):  
Experimental Study ◽  
Hemorrhagic Shock ◽  
The Body ◽  
Neural Mechanisms ◽  
Shock Model ◽  
Content Type ◽  
Organ Systems ◽  
The Brain ◽  
Fine Print

✓ The roles of various organ systems in preventing the phenomenon of irreversible hemorrhagic shock were studied in dogs by artificially maintaining or depriving these systems of circulation. It was found that depriving the abdominal viscera of circulation did not necessarily result in death if the heart and brain were perfused. If the heart was maintained at normal pressures while the rest of the body was subjected to what would have otherwise been a lethal period of shock, the animal nevertheless survived. Thus, in the standard “35 mm Hg shock model” the heart seemed to be crucial. However, in the “30 mm Hg shock model” death occurred even if the heart was adequately perfused, indicating that failure of neural mechanisms accounts for irreversibility at these levels of hypotension.

scholarly journals Daily Rhythms of the Body and the Biological Clock

2021 ◽  
Vol 9 ◽  
Author(s):  
Tamar Shochat ◽  
Eran Tauber
Keyword(s):  
Environmental Changes ◽  
Biological Clock ◽  
External Environment ◽  
Light Level ◽  
The Body ◽  
Modern World ◽  
Daily Rhythms ◽  
Light Levels ◽  
Daily Cycles ◽  
The Brain

Earth’s rotation creates a cycle of day and night, which is observed as changes in light levels and temperature. During evolution, plants and animals adapted to these cycles, developing daily cycles of physical and behavioral processes that are driven by a central biological clock, also known as the circadian clock. Even in the absence of changes in light between day and night, the biological clock creates cycles called circadian rhythms. The nervous system transfers information about the external light level to the biological clock in the brain, which matches the clock’s cycle to the external environment. The biological clock prepares the body for environmental changes. The modern world has created disruptions in the circadian clock’s timing, because of electrical lighting, flights to other time zones, and work during the night. The study of chronobiology studies the mechanisms of the biological clock and the clock’s influence on human health.

scholarly journals Fever in the Neurointensive Care Unit

2019 ◽  
Vol 06 (03) ◽  
pp. 275-283
Author(s):  
Siddharth Chavali ◽  
Manjari Tripathi ◽  
Vanitha Rajagopalan
Keyword(s):  
Neurocritical Care ◽  
The Body ◽  
Cerebral Damage ◽  
Systemic Complications ◽  
Mortality And Morbidity ◽  
Neurointensive Care Unit ◽  
Secondary Insult ◽  
Organ Systems ◽  
Cerebral Diseases ◽  
The Brain

AbstractFever occurs commonly in patients admitted to the neurocritical care unit. An increase in the body temperature is known to have deleterious effects on patients with acute nervous system injury and in most cases is associated with an increase in mortality and morbidity of these patients. There are multiple causes of fever in these patients. Due to the potentially devastating effects of fever in patients with cerebral diseases, it warrants treatment in every case. In all patients with acute cerebral damage, treatment of fever and maintenance of euthermia is important to obtain a better functional recovery and to limit any further secondary insult to the brain. This review highlights the etiology and pathophysiology of fever in neurocritical care unit patients, the effects on various organ systems and associated systemic complications, and the evaluation and different therapeutic options available for the management of fever in this patient subset.

In situ localization of the per clock protein during development of Drosophila melanogaster

1988 ◽  
Vol 8 (12) ◽  
pp. 5378-5385
Author(s):  
L Saez ◽  
M W Young
Keyword(s):  
Drosophila Melanogaster ◽  
Biological Clock ◽  
Biological Rhythms ◽  
Adult Brain ◽  
Genetic Studies ◽  
Ring Gland ◽  
Ultradian Rhythmicity ◽  
The Brain ◽  
Clock Protein

The per locus influences biological rhythms in Drosophila melanogaster. In this study, per transcripts and proteins were localized in situ in pupae and adults. Earlier genetic studies have demonstrated that per expression is required in the brain for circadian locomotor activity rhythms and in the thorax for ultradian rhythmicity of the Drosophila courtship song. per RNA and proteins were detected in a restricted group of cells in the eyes and optic lobes of the adult brain and in many cell bodies in the adult and pupal thoracic ganglia. per products were also found in the pupal ring gland complex, a tissue involved in rhythmic aspects of Drosophila development. Abundant expression was seen in gonadal tissue. No biological clock phenotypes have been reported for this tissue in any of the per mutants, per protein mapped to different subcellular locations in different tissues. The protein accumulated in or around nuclei in some cells and appeared to be cytoplasmic in others.

scholarly journals PULSATILE DRUG DELIVERY SYSTEM-A TECHNIQUE OF DELIVERING DRUG IN ACCORDANCE WITH BIOLOGICAL CLOCK - A REVIEW

2021 ◽  
Vol 9 (4) ◽  
pp. 101-124
Author(s):  
Chiluvuru Vani ◽  
◽  
K. Srinivas Reddy ◽  
Keyword(s):  
Drug Delivery ◽  
Drug Delivery System ◽  
Delivery System ◽  
Biological Clock ◽  
Biological Rhythms ◽  
Immediate Release ◽  
Dosage Forms ◽  
The Body ◽  
Solid Dosage ◽  
Pulsatile Drug Delivery

Over last 30 years pulsatile drug delivery system has achieved a lot of importance in drug delivery technology. And the reason why this pulsatile drug delivery is gaining importance is because of its strategy of delivering drug molecule at right place, right time. There are certain diseases which are controlled by biological clock of our body and follow circadian rhythms like congestive heart failure, asthma, rheumatoid arthritis ,osteoarthritis, inflammatory disorders and other hormonal disorders, for this type of diseases conventional solid dosage forms like immediate release tablets or modified dosage forms like sustained, controlled release tablets cant give the required therapeutic response and also for such diseases delivering the drug at right time in right amount is very important. And that task is accomplished by this pulsatile drug delivery system. These pulsatile drug delivery framework is planned by the organic mood i.e., biological rhythms of the body, and medication conveyance is worked with by as per disease cadence. The rule for the utilization of pulsatile drug delivery of the medications is the place where a consistent drug discharge isnt wanted. The principle for the utilization of pulsatile release of the medications is the place where a steady drug discharge isnt wanted, yet drug release must be planned in such a way that, quick medication discharge is accomplished after the lag time. Current review examined the clarifications for improvement of pulsatile drug delivery framework in accordane with body circadian rhythm, kinds of the illness during which pulsatile discharge is required, order, assessments, benefits, impediments.

scholarly journals Biological rhythms in Arctic vertebrates

Rangifer ◽  
2000 ◽  
Vol 20 (2-3) ◽  
pp. 99 ◽  
Author(s):  
B. E.H. Van Oort ◽  
N. J.C. Tyler ◽  
E. Reierth ◽  
K.-A. Stokkan
Keyword(s):  
Rangifer Tarandus ◽  
Biological Clock ◽  
Biological Rhythms ◽  
Polar Regions ◽  
Physiological Control ◽  
Endogenous Rhythms ◽  
Arctic Species ◽  
Cyclical Fluctuations ◽  
Timing Mechanisms ◽  
The Brain

Many biological processes show regular cyclical fluctuations that persist throughout an organism's life; these range from the transcription of DNA to patterns of behaviour. Persistent, cyclical phenomena of this kind are a fundamental feature of all organisms. They are governed primarily by endogenous rhythms generated by a 'biological clock' situated in the brain. Normally, however, the expression of the clock is modulated to a greater or lesser extent by environmental cues. This paper reviews the physiological control of the temporal organisation of cycles in vertebrates and, in particular, explores their regulation in arctic species like reindeer (Rangifer tarandus L.). We emphasise how exposure to the photoperiodic conditions that characterise polar regions places special demands on timing mechanisms and how arctic species, therefore, are of particular interest for the study of biological rhythms. Thus far, behavioural and physiological studies of these species show that arctic reindeer (and ptarmigan) appear to be truly opportunistic in summer and wintet, seemingly without any active biological clock and that they are, instead, driven directly by photoperiod. This situation, if confirmed, would be unique among vertebrates.

scholarly journals Neurophysiology of Basic Molecules Affecting Sleep and Wakefulness Mechanisms, Fundamentals of Sleep Pharmacology

2021 ◽  
Author(s):  
Murat Kayabekir
Keyword(s):  
Follicle Stimulating Hormone ◽  
Electrical Signal ◽  
The Body ◽  
Pharmacological Agents ◽  
Gaba A ◽  
Sleep Physiology ◽  
Other Substances ◽  
Signal Changes ◽  
Healthy Functioning ◽  
The Brain

As part of the biological rhythm, the human brain has a healthy functioning with the ability to differentiate between day and night hours in any given day (sleep rhythm, life rhythm). From the control of hormone levels to muscle tonus, from the regulation of respiratory rate to the content of our thoughts, sleep has an impact on all bodily and cognitive functions. It is not surprising to see such effects of sleep on the body as it leads to significant changes in the electrical activity of the brain in general. Electrical signal changes in the brain (sleep-wakefulness rhythm) are regulated by neurohormonal molecules and their receptors in the body. Neurotransmitters that control sleep and wakefulness can be listed as “Glutamate, Acetylcholine, Histamine, Norepinephrine and GABA”. Main hormones are: Melatonin, Corticotropin Releasing Hormone (CRH), cortisol, prolactin, Growth Hormone (GH), Insulin like Growth Factor (IGF-1, Somatomedin-C), Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH), progesterone, estrogen, testosterone, catecholamines, leptin and neuropeptide Y″. The effects of pharmacological agents on sleep and wakefulness cycles are materialized through the following molecules and their receptors: Hypnotics (GABA A agonists, benzodiazepines, gabapentin, tiagabine), sedative antidepressants (tricyclic antidepressants, trazadone, mitrazapine), antihistamines, medications used for the treatment of sleeplessness (melatonin and melatonin analogues), amphetamine (most commonly used stimulant), secretion of monoamines (dopamine), non-amphetamine stimulants used in the treatment of hypersomnia and narcolepsy (modafinil, bupropion, selegiline, caffeine) and other substances (alcohol, nicotine, anesthetics). To the extent we can conceptualize the physiological mechanisms of these basic molecules listed above and the regions they affect, we can appreciate the effects of these substances on sleep physiology and sleep disorders.

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