scholarly journals The Kidney Clock Contributes to Timekeeping by the Master Circadian Clock

2019 ◽  
Vol 20 (11) ◽  
pp. 2765 ◽  
Author(s):  
Jihwan Myung ◽  
Mei-Yi Wu ◽  
Chun-Ya Lee ◽  
Amalia Ridla Rahim ◽  
Vuong Hung Truong ◽  
...  

The kidney harbors one of the strongest circadian clocks in the body. Kidney failure has long been known to cause circadian sleep disturbances. Using an adenine-induced model of chronic kidney disease (CKD) in mice, we probe the possibility that such sleep disturbances originate from aberrant circadian rhythms in kidney. Under the CKD condition, mice developed unstable behavioral circadian rhythms. When observed in isolation in vitro, the pacing of the master clock, the suprachiasmatic nucleus (SCN), remained uncompromised, while the kidney clock became a less robust circadian oscillator with a longer period. We find this analogous to the silencing of a strong slave clock in the brain, the choroid plexus, which alters the pacing of the SCN. We propose that the kidney also contributes to overall circadian timekeeping at the whole-body level, through bottom-up feedback in the hierarchical structure of the mammalian circadian clocks.

2021 ◽  
Vol 11 (1) ◽  
pp. 82
Author(s):  
Ida Cariati ◽  
Roberto Bonanni ◽  
Gabriele Pallone ◽  
Giuseppe Annino ◽  
Virginia Tancredi ◽  
...  

In the past 40 years, scientific research has shown how Whole Body Vibration concept represents a strong stimulus for the whole organism. Low (<30 Hz), medium (30–80 Hz), and high (>80 Hz) frequency vibrations can have both positive and negative effects, depending on the oscillation type and duration of exposure to which the body is subjected. However, very little is known about the effects of vibratory training on the brain. In this regard, we verified whether three vibratory training protocols, differing in terms of vibration frequency and exposure time to vibration, could modulate synaptic plasticity in an experimental mouse model, by extracellular recordings in vitro in hippocampal slices of mice of 4 and 24 months old. Our results showed that vibratory training can modulate synaptic plasticity differently, depending on the protocol used, and that the best effects are related to the training protocol characterized by a low vibration frequency and a longer recovery time. Future studies will aim to understand the brain responses to various types of vibratory training and to explore the underlying mechanisms, also evaluating the presence of any structural and functional changes due to vibratory training.


1976 ◽  
Vol 15 (05) ◽  
pp. 248-253
Author(s):  
A. K. Basu ◽  
S. K. Guha ◽  
B. N. Tandon ◽  
M. M. Gupta ◽  
M. ML. Rehani

SummaryThe conventional radioisotope scanner has been used as a whole body counter. The background index of the system is 10.9 counts per minute per ml of sodium iodide crystal. The sensitivity and derived sensitivity parameters have been evaluated and found to be suitable for clinical studies. The optimum parameters for a single detector at two positions above the lying subject have been obtained. It has been found that for the case of 131I measurement it is possible to assay a source located at any point in the body with coefficient of variation less than 5%. To add to the versatility, a fixed geometry for in-vitro counting of large samples has been obtained. The retention values obtained by the whole body counter have been found to correlate with those obtained by in-vitro assay of urine and stool after intravenous administration of 51Cr-albumin.


2008 ◽  
Vol 396-398 ◽  
pp. 569-572
Author(s):  
Fumio Watari ◽  
Shigeaki Abe ◽  
I.D. Rosca ◽  
Atsuro Yokoyama ◽  
Motohiro Uo ◽  
...  

Nanoparticles may invade directly into the internal body through the respiratory or digestive system and diffuse inside body. The behavior of nanoparticles in the internal body is also essential to comprehend for the realization of DDS. Thus it is necessary to reveal the internal dynamics for the proper treatments and biomedical applications of nanoparticles. In the present study the plural methods with different principles such as X-ray scanning analytical microscope (XSAM), MRI and Fluorescent microscopy were applied to enable the observation of the internal diffusion of micro/nanoparticles in the (1) whole body level, (2) inner organ level and (3) tissue and intracellular level. Chemical analysis was also done by ICP-AES for organs and compared with the results of XSAM mapping.


1924 ◽  
Vol 39 (4) ◽  
pp. 533-542 ◽  
Author(s):  
James E. McCartney

These studies fail to confirm the statements previously made that microorganisms of the class of the globoid bodies of poliomyelitis may be cultivated in the Smith-Noguchi medium from the so called virus of encephalitis lethargica. They show equally that the herpes virus does not multiply in this medium. The experiments indicate, moreover, that the medium is unfavorable to the survival of the virus, while ordinary broth under aerobic conditions is more favorable for maintaining the activity of both the encephalitic and the herpes viruses. Probably no multiplication of either takes place in the latter medium but merely a survival, and for a maximum period of 6 days in the broth itself, and 12 days in the fragment of brain tissue immersed in the broth. Finally, it has been shown that with a suitable technique the viruses can be passed from the brain of one rabbit to that of another through a long series without contamination with cocci or other common bacterial forms. Hence we regard all reports of the finding of ordinary bacteria in the brain of cases of epidemic or lethargic encephalitis as instances of mixed or secondary infection arising during life, or examples of postmortem invasion of the body, or of faulty technique at the autopsy.


2021 ◽  
Author(s):  
Andrew D. Beale ◽  
Priya Crosby ◽  
Utham K. Valekunja ◽  
Rachel S. Edgar ◽  
Johanna E. Chesham ◽  
...  

AbstractCellular circadian rhythms confer daily temporal organisation upon behaviour and physiology that is fundamental to human health and disease. Rhythms are present in red blood cells (RBCs), the most abundant cell type in the body. Being naturally anucleate, RBC circadian rhythms share key elements of post-translational, but not transcriptional, regulation with other cell types. The physiological function and developmental regulation of RBC circadian rhythms is poorly understood, however, partly due to the small number of appropriate techniques available. Here, we extend the RBC circadian toolkit with a novel biochemical assay for haemoglobin oxidation status, termed “Bloody Blotting”. Our approach relies on a redox-sensitive covalent haem-haemoglobin linkage that forms during cell lysis. Formation of this linkage exhibits daily rhythms in vitro, which are unaffected by mutations that affect the timing of circadian rhythms in nucleated cells. In vivo, haemoglobin oxidation rhythms demonstrate daily variation in the oxygen-carrying and nitrite reductase capacity of the blood, and are seen in human subjects under controlled laboratory conditions as well as in freely-behaving humans. These results extend our molecular understanding of RBC circadian rhythms and suggest they serve an important physiological role in gas transport.


2017 ◽  
Vol 118 (4) ◽  
pp. 2499-2506 ◽  
Author(s):  
A. Pomante ◽  
L. P. J. Selen ◽  
W. P. Medendorp

The vestibular system provides information for spatial orientation. However, this information is ambiguous: because the otoliths sense the gravitoinertial force, they cannot distinguish gravitational and inertial components. As a consequence, prolonged linear acceleration of the head can be interpreted as tilt, referred to as the somatogravic effect. Previous modeling work suggests that the brain disambiguates the otolith signal according to the rules of Bayesian inference, combining noisy canal cues with the a priori assumption that prolonged linear accelerations are unlikely. Within this modeling framework the noise of the vestibular signals affects the dynamic characteristics of the tilt percept during linear whole-body motion. To test this prediction, we devised a novel paradigm to psychometrically characterize the dynamic visual vertical—as a proxy for the tilt percept—during passive sinusoidal linear motion along the interaural axis (0.33 Hz motion frequency, 1.75 m/s2peak acceleration, 80 cm displacement). While subjects ( n=10) kept fixation on a central body-fixed light, a line was briefly flashed (5 ms) at different phases of the motion, the orientation of which had to be judged relative to gravity. Consistent with the model’s prediction, subjects showed a phase-dependent modulation of the dynamic visual vertical, with a subject-specific phase shift with respect to the imposed acceleration signal. The magnitude of this modulation was smaller than predicted, suggesting a contribution of nonvestibular signals to the dynamic visual vertical. Despite their dampening effect, our findings may point to a link between the noise components in the vestibular system and the characteristics of dynamic visual vertical.NEW & NOTEWORTHY A fundamental question in neuroscience is how the brain processes vestibular signals to infer the orientation of the body and objects in space. We show that, under sinusoidal linear motion, systematic error patterns appear in the disambiguation of linear acceleration and spatial orientation. We discuss the dynamics of these illusory percepts in terms of a dynamic Bayesian model that combines uncertainty in the vestibular signals with priors based on the natural statistics of head motion.


2016 ◽  
Vol 16 (1) ◽  
pp. 9
Author(s):  
Ummu Balqis ◽  
Darmawi Darmawi ◽  
Maryam Maryam ◽  
Muslina Muslina ◽  
Abdullah Hamzah ◽  
...  

ABSTRAK. Tujuan penelitian ini untuk mengetahui motilitas Ascaridia galli dewasa dalam ekstrak etanol biji Veitchia merrillii. Ekstrak etanol V. merrillii dianalisis fitokimia. Sebanyak 16 ekor cacing A. galli dewasa dibagi kedalam empat kelompok. Cacing pada kelompok pertama adalah kelompok tanpa perlakuan. Cacing pada kelompok kedua diberi 0,6 mg/ml levamisole. Cacing pada masing-masing kelompok ketiga dan keempat diberi 50 dan 100 mg/ml crude ekstrak biji V. merrillii. Motilitas A. galli ditentukan dalam skor persentase setelah 12, 24, 36 jam dengan menggunakan kriteria: 3 (badan bergerak), 2 (hanya sebagian badan bergerak), 1 (tidak bergerak tetapi masih hidup), 0 (mati). Hasil fitokimia V. merrillii mengandung alkaloids, saponins, tannins, flavonoids, terpenoids. Ekstrak biji V. merrillii dosis 100 mg/ml secara in vitro dapat mempersingkat selama 12 jam waktu motilitas cacing A. galli dewasa. Penelitian ini mengindikasikan potensi anthelmintik berbasis herbal untuk pengendalian A. galli.  (Motility of Ascaridia galli adult worms in vitro in ethanolic extracts of Nuts Veitchia merrillii) ABSTRACT. The purpose of this research was to know the motility of Ascaridia galli adult worms in aqueous ethanolic extracts of nuts Veitchia merrillii. The ethanolic extract of the V. merrillii was analyzed. Amount of sixteen head A. galli adult worms were divided into four groups. The first group, worms were left as un-treated normal controls. The second group, worms were treated with concentrations of 0,6 mg/ml levamisole. The third and fourth group, worms were treated with crude aqueous ethanolic extract of 50 and 100 mg/ml concentrations nuts of the V. merrillii, respectively. Motility of A. galli were determined after 12, 24, 36 hour by mean of persentage scored using the following criteria: 3 (moving whole body), 2 (moving only parts of the body), 1 (immobile but alive), and 0 (died). The result of phytochemical V. merrillii contains alkaloids, saponins, flavonoids, tannins, and terpenoids. V. merrillii nuts extract concentrations of 100 mg/ml in vitro can shorten the time motility A. galli adult worms for 12 hours. The study indicated the potential for developing herbal-based anthelmintics to control A. galli.


2020 ◽  
Vol 7 (1) ◽  
pp. 11-18
Author(s):  
Noni Zakiah ◽  
Vonna Aulianshah ◽  
T. Maulana Hidayatullah ◽  
Faridah Hanum

Kegunaan labu kuning di Indonesia masih sebatas daging buah yang dapat diolah menjadi panganan seperti kue basah, kolak dan sayur berkuah. Secara empiris, biji labu kuning telah digunakan untuk mengatasi cacingan. Penelitian ini dilakukan untuk mengetahui mortalitas cacing gelang (Ascaridia galli) dalam ekstrak etanol biji labu kuning (Cucurbita moschata Duchesne). Penelitian ini menggunakan 25 ekor Ascaridia galli yang dibagi menjadi 5 kelompok, kelompok I kontrol negatif menggunakan larutan NaCl fisiologis, kelompok II kontrol positif menggunakan larutan pirantel pamoat 0,5 %, kelompok III, IV dan V berturut-turut menggunakan 25 mg/ml, 50 mg/ml dan 100 mg/ml ekstrak etanol biji labu kuning. Parameter penelitian ini ditentukan dengan melihat persentase nilai skor pasca inkubasi 12 jam, 24 jam, dan 36 jam. Skor 3 diberikan apabila seluruh tubuh Ascaridia galli bergerak, skor 2 diberikan jika hanya sebagian tubuh Ascaridia galli bergerak, skor 1 jika Ascaridia galli diam tetapi masih hidup, dan skor 0 apabila Ascaridia galli mati. Hasil uji in vitro dengan perlakuan 25 mg/ml ekstrak etanol biji labu kuning menyebabkan kematian 3 ekor Ascaridia galli  atau 60% pasca inkubasi 36 jam, sedangkan ekstrak etanol biji labu kuning dengan perlakuan 50 mg/ml, 100 mg/ml dan kelompok kontrol positif mengakibatkan kematian 4 ekor Ascaridia galli atau 80% pasca inkubasi 36 jam. Dari hasil penelitian disimpulkan bahwa ekstrak etanol biji labu kuning (Cucurbita moschata Duchesne) dosis 25 mg/ml, 50 mg/ml, dan 100 mg/ml secara in vitro dalam waktu 36 jam mampu mengakibatkan mortalitas Ascaridia galli. The use of yellow pumpkin in Indonesia is still limited to fruit meat that can be processed into snacks such as soggy cakes, porridge and vegetable soup. This research was conducted to determine the mortality of Ascaridia galli in ethanol extract of yellow pumpkin seeds (Cucurbita moschata Duchesne). This study used 25 Ascaridia galli which were divided into 5 groups, group I was negative control using physiological NaCl solution, group II was positive control using 0.5% pirantel pamoate solution, group III, IV and V respectively used 25 mg / ml, 50 mg/ml and 100 mg/ml ethanol extract of yellow pumpkin seeds. The parameters of this study were determined by looking at the percentage of post-incubation scores 12 hours, 24 hours, and 36 hours. A score of 3 is given if the whole body of Ascaridia galli moves, a score of 2 is given if only part of the body of Ascaridia galli moves, a score of 1 if Ascaridia galli is still but still alive, and a score of 0 if Ascaridia galli dies. In vitro test results with 25 mg/ml ethanol extract of pumpkin seeds caused 3 deaths of Ascaridia galli or 60% after incubation for 36 hours, while ethanol extract of yellow pumpkin seeds treated with 50 mg / ml, 100 mg/ml and positive control group resulting in the death of 4 Ascaridia galli or 80% after 36 hours incubation. From the results of the study concluded that the ethanol extract of yellow pumpkin seeds (Cucurbita moschata Duchesne) doses of 25 mg / ml, 50 mg / ml, and 100 mg / ml in vitro within 36 hours can lead to Ascaridia galli mortality.


PEDIATRICS ◽  
1951 ◽  
Vol 7 (2) ◽  
pp. 269-293
Author(s):  
CHARLES C. CHAPPLE

A study has been made of the known phenomena which affect the biologic organism. Certain correlations have been found and other correlations are logically inferred. The common grounds of anatomic structures, the anatomic responses to endocrine stimuli, the interrelationships and interdependencies of the endocrines and external stimuli have been followed and have been related to cellular permeability and hyaluronic acid. Cellular phases, including the rhythmic alternations in physiologic functions, have been delineated and their importance stressed. Further, the probability is advanced that this rhythmicity originates physiologically in the brain but that the brain itself is capable of receiving transmissions from within and without the body, and disseminating them, again rhythmically, in normal or altered amplitude and frequency. Further experimental evidence of these correlations and their practical extrapolations into drug actions and the therapy of infections and metabolic disease will be reported and will include clinical, animal and in vitro studies. At present, the following conclusions seem justified: 1. No component of the body is capable of independent action. 2. Action in any component is reflected, according to its magnitude and directness of application, upon all the body. 3. All such actions are mediated by the brain. 4. There is a dynamic, rhythmic cyclicity in physiologic action which can be altered in amplitude and frequency. 5. These rhythms are alternations of cellular tenseness and relaxation. 6. The concomitants of the tense phase are compactness, impermeability, electric conductivity and contraction of all cells, and these characteristics might be described collectively as the factors operative in maturing the cell. The concomitants of the relaxed phase are laxness, permeability, electric resistance and expansion of all cells and are factors of growth. 7. The phase of tenseness is accompanied by an increase in certain hormonal activities and that of relaxation by an increase in others. 8. The hormones may be causes of the phase or the results of it. 9. Infectious disease cannot act as an extraneous agent capable of bringing its own engine into such a highly integrated mechanism but must act on the body through its ability to affect one of the body's mechanisms. 10. Drugs must act through the same channels available to disease. 11. Foods may contain, in addition to their caloric content, components capable of stimulating either the phase of cellular expansion or cellular compaction, particularly foods from the reproductive systems of plants or animals (milk, eggs, cereal, for example). 12. Vitamins each stimulate one phase and should be evaluated in terms of positive actions. 13. Inherent growth and maturation factors are not of fixed capacity in an individual but beyond certain limits must be supplied him or applied to him constantly. 14. The hormone most manifest in the tense phase is estrogen and so may be considered the maturation factor, and the one most manifest in the phase of relaxation or cell division is progesterone, which may be considered the growth factor.


2019 ◽  
Vol 21 (Supplement_3) ◽  
pp. iii58-iii58
Author(s):  
J Rowlinson ◽  
P McCrorie ◽  
S Smith ◽  
D Barrett ◽  
D Kim ◽  
...  

Abstract BACKGROUND Conventional oral or intravenous chemotherapy distributes drugs to the whole body whereby systemic toxicity to healthy parts of the body (e.g. bone marrow failure) limits the maximum dose that can be achieved in the brain. This presents a particular concern for CNS tumours where the blood-brain-barrier (BBB) restricts drug influx from the circulation. The ability to deliver chemotherapy locally at the tumour site offers the opportunity to target residual cancer cells post-surgery whilst minimising systemic toxicity. We have developed a poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) polymer matrix that forms a porous paste at room temperature when mixed with chemotherapy-containing saline, solidifying only at body temperature, with close apposition to the irregular surgical cavity. It is important that we can observe whether the drugs released from PLGA/PEG can penetrate brain parenchyma beyond the surgical resection margin at therapeutic doses. Currently the only way to measure the distribution of drugs in the body is to inject radioactive drugs into an animal. We aim to establish drug distribution parameters using label-free mass spectrometry imaging methods, prior to selection of drug formulations for clinically-relevant in vivo models. Drugs that penetrate the brain the furthest will be identified as good candidates for localised brain cancer drug delivery using PLGA/PEG paste. MATERIAL AND METHODS Diffusion rates were measured by examining the proportion of olaparib, dasatnib, carboplatin, etoposide, paclitaxel and gemcitabine at 2mg/ml concentration, which passes through 1mm slices of rat brain tissue within Franz cell chambers over a 6 hour period. The spatio-temporal distribution of label-free olaparib and dasatinib within mouse brain homogenate was quantitatively measured using innovative 3D OrbiSIMS, a hybrid time-of-flight / OrbitrapTM secondary ion mass spectrometer. RESULTS Within the Franz cell model, carboplatin and gemcitabine showed the highest diffusion rate diffusion at 16.4 and 6.53 µg/cm2/h respectively whereas olaparib, etoposide and paclitaxel were relatively poorly diffused at 1.87, 3.82 and 2.27 µg/cm2/h respectively. The minimum threshold of OrbiSIMS detection for label-free olaparib and dasatinib ions was 0.025 mg/ml and 0.2 mg/ml respectively throughout brain homogenate. CONCLUSION This study demonstrates different diffusion rates through brain tissue, between label-free chemotherapy drugs of distinct chemistries, with highest diffusion rates observed for carboplatin and gemcitabine. We also demonstrate label-free detection of olaparib and dasatinib using the innovative 3D OrbiSIMS method. These models will facilitate the rapid identification of agents most amenable for localised biomaterial-based chemotherapy delivery with high brain penetrance.


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