Effect of amobarbital on the course of human dark adaptation

1961 ◽  
Vol 16 (2) ◽  
pp. 361-366 ◽  
Author(s):  
G. W. Granger
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Oral Administration ◽  
White Light ◽  
Dark Adaptation ◽  
Light Adaptation ◽  
Visual Adaptation ◽  
Test Field ◽  
The Central Nervous System ◽  
The Stability

Following light adaptation to a luminance of 120 mL for 5 minutes, absolute thresholds for a centrally fixated, 7-degree test field in 'white' light were measured during the course of 30 minutes' dark adaptation. Viewing was monocular and the measuring light was exposed in 0.018-second flashes. The resulting curves, defining the relation between log threshold luminance and time in the dark, displayed the typical features of 'rod' dark adaptation and were found to be highly reproducible in three experienced observers. Neither the shape of the curves nor their position along the log luminance axis was affected by the oral administration of a sedative dose (0.30 gm/70 kg) of amobarbital. It was concluded that the results supported the views of Hecht and other photochemical theorists concerning the stability of human dark adaptation and its resistance to fluctuations in the state of the central nervous system, but were not necessarily incompatible, as was sometimes supposed, with the hypothesis of a neural component in visual adaptation. Submitted on May 23, 1960

scholarly journals Brain Targeting of anti-HIV Nucleosides: in vitro and in vivo Evaluation of 6-chloro-2′,3′-dideoxypurine, a Lipophilic Prodrug of 2′,3′-dideoxyinosine

1994 ◽  
Vol 5 (5) ◽  
pp. 304-311 ◽  
Author(s):  
K. J. Doshi ◽  
F. D. Boudinot ◽  
J. M. Gallo ◽  
R. F. Schinazi ◽  
C. K. Chu
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Oral Administration ◽  
Intravenous Administration ◽  
Brain Targeting ◽  
The Central Nervous System ◽  
Intravenous And Oral Administration ◽  
The Brain

Lipophilic 6-halo-2′,3′-dideoxypurine nucleosides may be useful prodrugs for the targeting of 2′,3′-dideoxyinosine (ddl) to the central nervous system. The purpose of this study was to evaluate the potential effectiveness of 6-chloro-2′,3′-dideoxypurine (6-CI-ddP) for the targeting of ddl to the brain. In vitro studies indicated that the adenosine deaminase-mediated biotransformation of 6-CI-ddP to ddl was more rapid in mouse brain homogenate than in mouse serum. The brain distribution of 6-CI-ddP and ddl was assessed in vivo in mice following intravenous and oral administration of the prodrug or parent drug. Brain concentrations of ddl were similar after intravenous administration of 6-CI-ddP or ddl. However, after oral administration of the 6-CI-ddP prodrug, significantly greater concentrations of ddl were seen in the brain compared to those found after oral administration of ddl. The brain:serum AUG ratio (expressed as a percentage) of ddl after intravenous administration of 50 mg kg−1 of the active nucleoside was 3%. Following oral administration of 250 mg kg−1 ddl, low concentrations of ddl were detected in the brain. Brain:serum AUC ratios following intravenous and oral administration of the prodrug 6-CI-ddP were 19–25%. Thus, brain:serum AUC ratios were 6- to 8-fold higher after prodrug administration than those obtained after administration of the parent nucleoside. Oral administration of 6-CI-ddP yielded concentrations of ddl in the brain similar to those obtained following intravenous administration. The results of this study provide further evidence that 6-CI-ddP may be a useful prodrug for delivering ddl to the central nervous system, particularly after oral administration.

Insulin secretion: mechanism of the stimulation by glucose

1975 ◽  
Vol 8 (1) ◽  
pp. 1-41 ◽  
Author(s):  
Erol Cerasi
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Insulin Secretion ◽  
Blood Glucose ◽  
Food Intake ◽  
Blood Glucose Level ◽  
Glucose Level ◽  
Glucose Concentration ◽  
The Central Nervous System ◽  
The Stability

Glucose is one of the substrates that is controlled with the most efficient hormonal mechanisms in higher organisms. The presence of tissues such as the central nervous system which, under normal conditions, depend solely on glucose as substrate, and the sporadic type of food intake with periods of fasting of various lengths in the mammalians necessitate that the distribution of energy-rich substrates among various tissues be continuously adjusted by changes in the secretion of a number of hormones. The efficiency of this system is evidenced by the stability of the blood glucose level in man, in whom after a carbohydrate-rich meal more than 70% of the glucose that has been ingested will be retained in the liver during a single passage of portal blood, resulting in only small changes of the glucose concentration in peripheral blood. Likewise, periods of fasting up to24–36 h are followed by modest to minimal reductions of the blood glucose level, the liver now supplying the circulation with the hexose.

scholarly journals The microbiota protects from viral-induced neurologic damage through microglia-intrinsic TLR signaling

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
D Garrett Brown ◽  
Raymond Soto ◽  
Soumya Yandamuri ◽  
Colleen Stone ◽  
Laura Dickey ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Oral Administration ◽  
Viral Replication ◽  
Viral Infection ◽  
Host Defense ◽  
Toll Like Receptor ◽  
Tlr Signaling ◽  
The Central Nervous System ◽  
The Brain

Symbiotic microbes impact the function and development of the central nervous system (CNS); however, little is known about the contribution of the microbiota during viral-induced neurologic damage. We identify that commensals aid in host defense following infection with a neurotropic virus through enhancing microglia function. Germfree mice or animals that receive antibiotics are unable to control viral replication within the brain leading to increased paralysis. Microglia derived from germfree or antibiotic-treated animals cannot stimulate viral-specific immunity and microglia depletion leads to worsened demyelination. Oral administration of toll-like receptor (TLR) ligands to virally infected germfree mice limits neurologic damage. Homeostatic activation of microglia is dependent on intrinsic signaling through TLR4, as disruption of TLR4 within microglia, but not the entire CNS (excluding microglia), leads to increased viral-induced clinical disease. This work demonstrates that gut immune-stimulatory products can influence microglia function to prevent CNS damage following viral infection.

scholarly journals DEGENERATIVE CHANGES IN THE CENTRAL NERVOUS SYSTEM OF JAPANESE MONKEYS INDUCED BY ORAL ADMINISTRATION OF ALUMINUM SALT

1989 ◽  
Vol 10 (1) ◽  
pp. 33-41 ◽  
Author(s):  
ICHIRO YANO ◽  
SOHEI YOSHIDA ◽  
YUSHIRO UEBAYASHI ◽  
FUMIO YOSHIMASU ◽  
YOSHIRO YASE
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Oral Administration ◽  
Degenerative Changes ◽  
Japanese Monkeys ◽  
The Central Nervous System

scholarly journals Humans exploit robust locomotion by improving the stability of control signals

2019 ◽  
Author(s):  
Alessandro Santuz ◽  
Leon Brüll ◽  
Antonis Ekizos ◽  
Arno Schroll ◽  
Nils Eckardt ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Older Age ◽  
Muscle Synergies ◽  
Rough Terrain ◽  
Control Signals ◽  
Age Related ◽  
The Central Nervous System ◽  
The Stability ◽  
Over Time

AbstractIs the control of movement less stable when we walk or run in challenging settings? One might intuitively answer affirmatively, given that adding constraints to locomotion (e.g. rough terrain, age-related impairments, etc.) imply less stable movements. We investigated how young and old humans synergistically activate muscles during locomotion, when different perturbation levels are introduced. Of these control signals, called muscle synergies, we then analyzed the stability over time. Surprisingly, we found that perturbations and older age force the central nervous system to produce more stable signals. These outcomes show that robust locomotion in challenging settings is achieved by increasing the stability of control signals, whereas easier tasks allow for more unstable control.

scholarly journals Uptake in the Central Nervous System of Geraniol Oil Encapsulated in Chitosan Oleate Following Nasal and Oral Administration

Pharmaceutics ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 106 ◽  
Author(s):  
Maria Bonferoni ◽  
Luca Ferraro ◽  
Barbara Pavan ◽  
Sarah Beggiato ◽  
Elena Cavalieri ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Cerebrospinal Fluid ◽  
Nervous System ◽  
Oral Administration ◽  
Amphiphilic Polymer ◽  
Nasal Administration ◽  
Dispersed Phase ◽  
Pharmacological Activities ◽  
Mean Diameter ◽  
The Central Nervous System

The pharmacological activities of geraniol include anticancer and neuroprotective properties. However, its insolubility in water easily induces separation from aqueous formulations, causing administration difficulties. Here we propose new emulsified formulations of geraniol by using the amphiphilic polymer chitosan-oleate (CS-OA) as surfactant to combine mucoadhesive and absorption enhancer properties with stabilization effects on the oil dispersion. The formulation based on CS-OA 2% (w/w) (G-CS-OA-2.0%) showed viscosity values compatible with oral and nasal administration to rats, and mean diameter of the dispersed phase of 819 ± 104 nm. G-CS-OA-2.0% oral administration sensibly increases the geraniol bioavailability with respect to coarse emulsions obtained without CS-OA (AUC values in the bloodstream were 42,713 ± 1553 µg∙mL−1∙min and 2158 ± 82 µg∙mL−1∙min following administration of 50 mg/kg or 1 mg/kg, respectively), and enhances the aptitude of geraniol to reach the central nervous system from the bloodstream (AUC values in the cerebrospinal fluid were 7293 ± 408 µg∙mL−1∙min and 399 ± 25 µg∙mL−1∙min after oral administration of 50 mg/kg or 1 mg/kg, respectively). Moreover, relevant geraniol amounts were detected in the cerebrospinal fluid following the G-CS-OA-2% nasal administration (AUC values in the cerebrospinal fluid were 10,778 ± 477 µg∙mL−1∙min and 5571 ± 290 µg∙mL−1∙min after nasal administration of 4 mg/kg or 1 mg/kg, respectively).

FEATURES OF THE FUNCTIONAL STATE OF THE CNS AND EFFICIENCY OF MEDICAL WORKERS OF PCR LABORATORIES DURING COVID-19 PANDEMIC

2021 ◽  
Author(s):  
V.V. Shkarin ◽  
◽  
N.I. Latyshevskaya ◽  
D.V. Orlov ◽  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Functional State ◽  
Functional System ◽  
Observation Group ◽  
Functional Capabilities ◽  
Functional Reserves ◽  
The Central Nervous System ◽  
Student’S T ◽  
The Stability

Abstract: The functional state of the central nervous system was determined by the method of variational chronoreflexometry. The calculated criteria for assessing the functional level of the nervous system (FLS, conventional units), the stability of the nervous reaction (SR, conventional units), the level of functional capabilities of the formed functional system (LFC, conventional units) were analyzed. The observation group was made up of medical workers of PCR laboratories during the COVID-19 pandemic. The results were processed by the variational-statistical method with the calculation of average values (M), representativeness errors (±m), the reliability of differences was determined by the Student's t-test using applied statistical packages Statistica 6.0. It was found that the functional state of the central nervous system in PCR laboratory workers is characterized by the development of significant fatigue and depletion of the functional reserves of the central nervous system, as evidenced by a significant decrease in the level of the formed functional system (FSL) from 2.40±0.04 to 2.13±0.095 units, the stability of the reaction (SR) to 66.25-74.54%. The ability of the central nervous system to form and maintain an adaptive functional system of adaptation to environmental factors significantly decreased by the end of the shift in the observation group by 43.12%- 48.01%. The identified features of the functional state of the central nervous system and the working capacity of medical workers in PCR laboratories during the COVID-19 pandemic will be used for further causation of changes in their health status in difficult working conditions.

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