scholarly journals Role of Food Consumption in the Mortality Response of Irradiated Rats Subjected to Prolonged Cold Exposure

1958 ◽  
Vol 195 (2) ◽  
pp. 271-275 ◽  
Author(s):  
Bernard D. Newsom ◽  
Donald J. Kimeldorf
Keyword(s):  
Mortality Rate ◽  
Food Consumption ◽  
Cold Exposure ◽  
Prolonged Exposure ◽  
Cold Environment ◽  
X Rays ◽  
Mortality Response ◽  
Maintain Body Weight ◽  
Inadequate Food Intake

Prolonged exposure to a low ambient temperature increases the 30-day mortality rate of irradiated rats. To determine if the increased mortality is due to a failure of the irradiated rat to adapt to the higher metabolic demands of a cold environment, the food consumption of irradiated (500r, 600r, 250 kv x-rays) animals was measured during 30 days of exposure at normal (23°C) or lowered (6°C) environmental temperature. The food consumption of irradiated animals was increased by exposure to cold; however, this increase was not sufficient to maintain body weight at a level comparable to nonirradiated animals. When the food consumption of nonirradiated animals was limited to that of irradiated animals during exposure to a 6°C environment, the mortality observed among nonirradiated animals was comparable to the increase in mortality induced by cold exposure of irradiated animals. These results suggest that the increased mortality rate of irradiated animals in a cold environment is related to an inadequate food intake.

Tolerance of rats to a cold environment during multiple exposures to a low dose of x rays

1961 ◽  
Vol 200 (5) ◽  
pp. 1039-1042 ◽  
Author(s):  
Bernard D. Newsom ◽  
Donald J. Kimeldorf
Keyword(s):  
Cold Exposure ◽  
Low Dose ◽  
Lethal Dose ◽  
Dose Fractionation ◽  
Cold Environment ◽  
X Rays ◽  
Time Intervals ◽  
Multiple Exposures ◽  
X Irradiation ◽  
Food Consumed

A lethal dose of X irradiation can be made sublethal by the fractionation of a dose into a series of smaller doses separated by adequate time intervals. The results reported here demonstrate how an environmental stress, such as cold, may affect this mitigating action of dose fractionation. Rats were maintained at 6 C while receiving a total dose of 600 r in one or eight exposures with various intervals between exposures. A greater interval was required between radiation exposures at 6 C than at 23 C to reduce the lethal response following irradiation. From the results of the food consumption measurements, it appears that cold exposure emphasizes the consequence of the reduced food intake which follows daily doses of 75 r in the rat. The irradiated rat was able to increase the amount of food consumed during cold exposure; however, the increase was not sufficient for adaptation. The lowered consumption which followed eight daily 75-r exposures was sufficient to cause death in pair-fed rats maintained at 6 C, but not at 23 C.

scholarly journals Tranilast treats cold-related hypertension by reducing the expression of NLRP3 inflammasome

2021 ◽  
Vol 1 (2) ◽  
pp. 95-101
Author(s):  
Hui Yu ◽  
Yun Zhou ◽  
Yu Duan ◽  
Yunlong Gao ◽  
Ning Fang ◽  
...  
Keyword(s):  
Cold Exposure ◽  
Nlrp3 Inflammasome ◽  
Receptor Protein ◽  
Control Group ◽  
Cold Environment ◽  
Sprague Dawley ◽  
Inhibitory Effects ◽  
Beneficial Action ◽  
To Receive

Abstract Objective Cold exposure is associated with increased prevalence of hypertension and the related severe cardiovascular events. Aberrant activation of the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome plays an important role in the development of hypertension. Tranilast (TR), an inhibitor of NLRP3, provides a useful pharmacological probe for exploring the role of NLRP3 in pathogenesis associated with inflammation and its potential application as a therapeutic agent. This study was designed to examine the effects of TR on NLRP3 and hypertension in rats exposed to cold environment to simulate the frigid-zone conditions. Methods and results Sprague Dawley (SD) rats were exposed to moderate cold temperature (4±1°C), and then were randomized to receive TR or vehicle for 3 weeks, while the control group was raised under rat room temperature (RT, 23±1°C). We found that cold exposure substantially increased blood pressure, NLRP3 inflammasome level, and fibrosis in aorta, which were reversed by TR. Conclusion TR has an anti-hypertensive property in cold environment, and this beneficial action is likely conferred by its inhibitory effects on inflammation and fibrosis. These findings suggest TR as a potential drug for the treatment of cold-induced hypertension.

The Pineal Gland and Stress: Effect of Pineal Stalk Section on the Plasma Corticosteroid Response to Cold in Rabbits

1979 ◽  
Vol 44 (3) ◽  
pp. 883-890 ◽  
Author(s):  
Robert W. Rivest ◽  
Kenneth D. Roberts ◽  
Franco Leporé
Keyword(s):  
Pineal Gland ◽  
Cold Exposure ◽  
Control Group ◽  
Sham Operation ◽  
Stress Effect ◽  
Cold Environment ◽  
Corticosterone Concentration ◽  
General Adaptation ◽  
Corticosteroid Response

To investigate the role of the pineal gland on plasma corticosteroid elevation during stress, a pineal stalk section was performed in rabbits implanted with a carotid cannula, while a comparable sham operation was carried out in a control group ( n = 8) similarly implanted. Six days after the surgery, the rabbits were exposed to a cold environment for 2 hr. Blood was withdrawn periodically throughout the 2 hr. of cold stress and for an additional 2 hr. after the rabbits were returned to their cages. Results show that plasma corticosteroids (cortisol + corticosterone) concentration in both groups rose during the cold exposure and gradually declined towards resting values after removal from the cold. The lesioned rabbits, however, exhibited an earlier and higher elevation in plasma corticosteroid levels in reaction to the cold. These observations suggest that the pineal stalk in normal animals influences the corticosteroid response to a stress in such a way as to increase the latency of its onset and decrease its amplitude. This effect is interpreted in the context of the general adaptation syndrome.

Digital x-ray mapping of nanometer-size supported bimetallic catalysts

1988 ◽  
Vol 46 ◽  
pp. 530-531
Author(s):  
L. T. Germinario
Keyword(s):  
Background Radiation ◽  
Metal Cluster ◽  
Single Element ◽  
Beam Diameter ◽  
X Rays ◽  
X Ray ◽  
Major Interest ◽  
Induced Changes

Understanding the role of metal cluster composition in determining catalytic selectivity and activity is of major interest in heterogeneous catalysis. The electron microscope is well established as a powerful tool for ultrastructural and compositional characterization of support and catalyst. Because the spatial resolution of x-ray microanalysis is defined by the smallest beam diameter into which the required number of electrons can be focused, the dedicated STEM with FEG is the instrument of choice. The main sources of errors in energy dispersive x-ray analysis (EDS) are: (1) beam-induced changes in specimen composition, (2) specimen drift, (3) instrumental factors which produce background radiation, and (4) basic statistical limitations which result in the detection of a finite number of x-ray photons. Digital beam techniques have been described for supported single-element metal clusters with spatial resolutions of about 10 nm. However, the detection of spurious characteristic x-rays away from catalyst particles produced images requiring several image processing steps.

Treatment of ebola and other infectious diseases: melatonin “goes viral”

2020 ◽  
Vol 3 (1) ◽  
pp. 43-57 ◽  
Author(s):  
Russel J Reiter ◽  
Qiang Ma ◽  
Ramaswamy Sharma
Keyword(s):  
Mortality Rate ◽  
Infectious Diseases ◽  
Hemorrhagic Shock ◽  
Safety Profile ◽  
Ebola Virus ◽  
Viral Infections ◽  
Virus Disease ◽  
Attractive Potential ◽  
Potential Treatment

This review summarizes published reports on the utility of melatonin as a treatment for virus-mediated diseases. Of special note are the data related to the role of melatonin in influencing Ebola virus disease. This infection and deadly condition has no effective treatment and the published works documenting the ability of melatonin to attenuate the severity of viral infections generally and Ebola infection specifically are considered. The capacity of melatonin to prevent one of the major complications of an Ebola infection, i.e., the hemorrhagic shock syndrome, which often contributes to the high mortality rate, is noteworthy. Considering the high safety profile of melatonin, the fact that it is easily produced, inexpensive and can be self-administered makes it an attractive potential treatment for Ebola virus pathology.  

scholarly journals The Role of Place of Delivery in Preventing Neonatal and Infant Mortality Rate in India

Geographies ◽  
2021 ◽  
Vol 1 (1) ◽  
pp. 47-62
Author(s):  
Ujjwal Das ◽  
Barkha Chaplot ◽  
Hazi Mohammad Azamathulla
Keyword(s):  
Mortality Rate ◽  
Infant Mortality ◽  
Neonatal Mortality ◽  
Public Hospitals ◽  
Infant Mortality Rate ◽  
Private Institutions ◽  
Public And Private ◽  
Place Of Delivery ◽  
At Home

Skilled birth attendance and institutional delivery have been advocated for reducing maternal, neonatal mortality and infant mortality (NMR and IMR). This paper examines the role of place of delivery with respect to neo-natal and infant mortality in India using four rounds of the Indian National Family Health Survey conducted in 2015–2016. The place of birth has been categorized as “at home” or “public and private institution.” The role of place of delivery on neo-natal and infant mortality was examined by using multivariate hazard regression models adjusted for clus-tering and relevant maternal, socio-economic, pregnancy and new-born characteristics. There were 141,028 deliveries recorded in public institutions and 54,338 in private institutions. The esti-mated neonatal mortality rate in public and private institutions during this period was 27 and 26 per 1000 live births respectively. The study shows that when the mother delivers child at home, the chances of neonatal mortality risks are higher than the mortality among children born at the health facility centers. Regression analysis also indicates that a professionally qualified provider′s antenatal treatment and assistance greatly decreases the risks of neonatal mortality. The results of the study illustrate the importance of the provision of institutional facilities and proper pregnancy in the prevention of neonatal and infant deaths. To improve the quality of care during and imme-diately after delivery in health facilities, particularly in public hospitals and in rural areas, accel-erated strengthening is required.

Reactive oxygen species in cell responses to toxic agents

2002 ◽  
Vol 21 (2) ◽  
pp. 85-90 ◽  
Author(s):  
L E Feinendegen
Keyword(s):  
Radiation Exposure ◽  
Mammalian Cells ◽  
Low Dose ◽  
X Rays ◽  
Low Dose Radiation ◽  
Cell Responses ◽  
Toxic Agents ◽  
Particle Tracks ◽  
Dose Radiation

This review first summarizes experimental data on biological effects of different concentrations of ROS in mammalian cells and on their potential role in modifying cell responses to toxic agents. It then attempts to link the role of steadily produced metabolic ROS at various concentrations in mammalian cells to that of environmentally derived ROS bursts from exposure to ionizing radiation. The ROS from both sources are known to both cause biological damage and change cellular signaling, depending on their concentration at a given time. At low concentrations signaling effects of ROS appear to protect cellular survival and dominate over damage, and the reverse occurs at high ROS concentrations. Background radiation generates suprabasal ROS bursts along charged particle tracks several times a year in each nanogram of tissue, i.e., average mass of a mammalian cell. For instance, a burst of about 200 ROS occurs within less than a microsecond from low-LET irradiation such as X-rays along the track of a Compton electron (about 6 keV, ranging about 1 μm). One such track per nanogram tissue gives about 1 mGy to this mass. The number of instantaneous ROS per burst along the track of a 4-meV ¬-particle in 1 ng tissue reaches some 70000. The sizes, types and sites of these bursts, and the time intervals between them directly in and around cells appear essential for understanding low-dose and low dose-rate effects on top of effects from endogenous ROS. At background and low-dose radiation exposure, a major role of ROS bursts along particle tracks focuses on ROS-induced apoptosis of damage-carrying cells, and also on prevention and removal of DNA damage from endogenous sources by way of temporarily protective, i.e., adaptive, cellular responses. A conclusion is to consider low-dose radiation exposure as a provider of physiological mechanisms for tissue homoeostasis.

scholarly journals Mortality rate in rheumatoid arthritis-related interstitial lung disease: the role of radiographic patterns

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Maria A. Nieto ◽  
Maria J. Rodriguez-Nieto ◽  
Olga Sanchez-Pernaute ◽  
Fredeswinda Romero-Bueno ◽  
Leticia Leon ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Interstitial Lung Disease ◽  
Mortality Rate ◽  
General Population ◽  
Lung Disease ◽  
Interstitial Pneumonia ◽  
Usual Interstitial Pneumonia ◽  
Multiple Regression Model ◽  
Multicentric Study

Abstract Background To assess mortality rate (MR) and standardized mortality rate (SMR) of rheumatoid arthritis-related interstitial lung disease (RA-ILD) patients and to evaluate the role of radiographic patterns in mortality. Methods A longitudinal multicentric study was conducted in RA-ILD patients from 2005 to 2015 and followed-up until October 2018 in Madrid. Patients were included in the Neumologia-Reumatología y Enfermedades Autoinmunes Registry, from diagnosis of ILD. The main outcome was all-cause mortality. The radiographic pattern at baseline [usual interstitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP), or others] was the independent variable. Covariables included sociodemographic and clinical data. Survival techniques were used to estimate MR, expressed per 1000 persons-year with their 95% confidence intervals [CI]. Cox multiple regression model was run to examine the influence of radiographic patterns on survival. SMR [CI] was calculated comparing MR obtained with MR expected in the general population of Madrid by indirect age-gender standardization. Results 47 patients were included with a follow-up 242 patients-year. There were 16 (34%) deaths, and most frequent causes were acute ILD exacerbation and pneumonia. MR was 64.3 [39.4–104.9], and 50% of the patients died at 8.3 years from ILD diagnosis. After adjusting for confounders, (UIP compared to NSIP was associated with higher mortality risk. The overall SMR was 2.57 [1.4–4.17]. Women of 60–75 years of age were the group with the highest SMR. Conclusions RA-ILD is associated with an excess of mortality compared to general population. Our results support that UIP increases the risk of mortality in RA-ILD, regardless other factors.

scholarly journals AGN surveys to study galaxy evolution along cosmic times

2013 ◽  
Vol 9 (S304) ◽  
pp. 180-186
Author(s):  
Luigi Spinoglio
Keyword(s):  
Star Formation ◽  
Galaxy Evolution ◽  
Energy Production ◽  
X Rays ◽  
Radio Frequencies ◽  
Ir Spectroscopic ◽  
Observational Techniques ◽  
Production Mechanisms

AbstractVarious observational techniques have been used to survey galaxies and AGN, from X-rays to radio frequencies, both photometric and spectroscopic. I will review these techniques aimed at the study of galaxy evolution and of the role of AGNs and star formation as the two main energy production mechanisms. I will then present as a new observational approach the far-IR spectroscopic surveys that could be done with planned astronomical facilities of the next future, such as SPICA from the space and CCAT from the ground.

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