Relative Effectiveness of Neutrons for Production of Delayed Biological Effects: I. Effect of Single Doses of Thermal Neutrons on Life Span of Mice

1958 ◽  
Vol 8 (1) ◽  
pp. 64 ◽  
Author(s):  
John B. Storer ◽  
Phyllis C. Sanders
Keyword(s):  
Life Span ◽  
Biological Effects ◽  
Relative Effectiveness ◽  
Thermal Neutrons

Plant polyphenols: free radical scavengers or chain-breaking antioxidants?

1995 ◽  
Vol 61 ◽  
pp. 103-116 ◽  
Author(s):  
Catherine Rice-Evans
Keyword(s):  
Biological Effects ◽  
Relative Effectiveness ◽  
Antioxidant Properties ◽  
Peroxyl Radicals ◽  
Free Radical Scavengers ◽  
Dietary Polyphenols ◽  
Chain Breaking ◽  
Lipid Peroxyl Radicals

There is increasing interest in the biological effects of tea- and wine-derived polyphenols and many studies in vitro and in vivo are demonstrating their antioxidant properties. Tea is a major source of dietary polyphenols and an even richer source of the flavanols, the catechins and catechin/gallate esters. Although there are limited studies on the bioavailability of the polyphenols, the absorption of flavanols in humans has been shown. The studies described in this chapter discuss the relative antioxidant potentials of the polyphenolic flavonoids in vitro against radicals generated in the aqueous phase in comparison with their relative effectiveness as antioxidants against propagating lipid peroxyl radicals, and how their activity influences that of α-tocopherol in low-density lipoproteins exposed to oxidative stress.

scholarly journals LASTING BIOLOGICAL EFFECTS OF EARLY ENVIRONMENTAL INFLUENCES

1968 ◽  
Vol 127 (4) ◽  
pp. 783-799 ◽  
Author(s):  
René Dubos ◽  
Russell W. Schaedler ◽  
Richard Costello
Keyword(s):  
Life Span ◽  
Biological Effects ◽  
Foster Mother ◽  
Adult Size ◽  
Specific Pathogen Free ◽  
Depressing Effect ◽  
Average Life ◽  
Average Life Expectancy ◽  
Complete Diet ◽  
Specific Pathogen

Newborn specific-pathogen-free mice (SPF) were separated from their mothers shortly after birth and immediately reallocated at random to foster mothers, each of which received eight young. Under these conditions, the growth rate and adult size of the young were profoundly and lastingly conditioned by some unidentified influence exerted by the foster mother. In SPF mice nursed by their own mothers, the diet of the latter during gestation and lactation, or during lactation alone, conditioned the weight of the young at weaning time, and throughout their whole life span. Lasting depression of growth has been achieved by minor alterations of the dam's diet, for example by lowering its content in magnesium, or in lysine and threonine. The growth-depressing effect so achieved persisted throughout the whole life-span of the young, even though they were given at weaning time and constantly thereafter unlimited amounts of an optimum diet. In contrast, the weight-depressing effect of a diet deficient in lysine and threonine administered to adult animals was completely and rapidly reversible when a complete diet was later substituted for the deficient one. Depression of growth resulting from nutritional experiences during gestation or lactation did not seem to affect adversely the health of the young, or to decrease their longevity. In fact, the results of two experiments in which the animals nursed by mothers on different diets, were kept undisturbed and on optimum diets throughout their whole life span, suggest that the smaller animals had a greater average life expectancy than the larger ones.

scholarly journals Bcl2-induced DNA replication stress promotes lung carcinogenesis in response to space radiation

2020 ◽  
Vol 41 (11) ◽  
pp. 1565-1575
Author(s):  
Maohua Xie ◽  
Dongkyoo Park ◽  
Gabriel L Sica ◽  
Xingming Deng
Keyword(s):  
Lung Cancer ◽  
Dna Replication ◽  
Reductase Activity ◽  
Biological Effects ◽  
Relative Effectiveness ◽  
Replication Stress ◽  
Space Radiation ◽  
Lung Carcinogenesis ◽  
Lung Targeting ◽  
Dna Replication Stress

Abstract Space radiation is characterized by high-linear energy transfer (LET) ionizing radiation. The relationships between the early biological effects of space radiation and the probability of cancer in humans are poorly understood. Bcl2 not only functions as a potent antiapoptotic molecule but also as an oncogenic protein that induces DNA replication stress. To test the role and mechanism of Bcl2 in high-LET space radiation-induced lung carcinogenesis, we created lung-targeting Bcl2 transgenic C57BL/6 mice using the CC10 promoter to drive Bcl2 expression selectively in lung tissues. Intriguingly, lung-targeting transgenic Bcl2 inhibits ribonucleotide reductase activity, reduces dNTP pool size and retards DNA replication fork progression in mouse bronchial epithelial cells. After exposure of mice to space radiation derived from 56iron, 28silicon or protons, the incidence of lung cancer was significantly higher in lung-targeting Bcl2 transgenic mice than in wild-type mice, indicating that Bcl2-induced DNA replication stress promotes lung carcinogenesis in response to space radiation. The findings provide some evidence for the relative effectiveness of space radiation and Bcl-2 at inducing lung cancer in mice.

Biological Effects of Inhaled 239PuO2 in Rats with Pre-existing Pulmonary Emphysema

1990 ◽  
Vol 9 (5) ◽  
pp. 295-308 ◽  
Author(s):  
D.L. Lundgren ◽  
J.L. Mauderly ◽  
W.W. Carlton ◽  
F.F. Hahn ◽  
J.H. Diel
Keyword(s):  
Life Span ◽  
Body Mass ◽  
Pulmonary Emphysema ◽  
Respiratory Function ◽  
Biological Effects ◽  
Lung Tumours ◽  
Neoplastic Lesions ◽  
Carcinogenic Effects ◽  
Normal Lungs ◽  
Over Time

The modifying effects of pre-existing pulmonary emphysema on the deposition, distribution, retention and effects of inhaled 239PuO2 in the rat were investigated. The presence of emphysema in the rats was documented by morphometric and respiratory function measurements. For rats exposed to similar airborne concentrations of 239PuO2, initial lung burdens of 239Pu per kg body mass were lower in rats with emphysema than in those without emphysema; however, the retention of 239Pu over time was similar in both groups. The distribution of 239Pu particles in the lungs of rats with emphysema tended to be more random than in the lungs of control rats. The life span, and incidences of non-neoplastic and neoplastic lesions in the lung, and risk of lung tumours per unit of alpha dose to the lungs in the rats with emphysema were similar to or less than in the control rats, when groups with similar initial lung burdens of 239Pu were compared. The results of this study suggest that humans with uncomplicated pulmonary emphysema are not necessarily more sensitive to the carcinogenic effects of inhaled 239PuO2 than individuals with normal lungs.

scholarly journals Activins Are Critical Modulators of Growth and Survival

2003 ◽  
Vol 17 (12) ◽  
pp. 2404-2417 ◽  
Author(s):  
Chester W. Brown ◽  
Liunan Li ◽  
Dianne E. Houston-Hawkins ◽  
Martin M. Matzuk
Keyword(s):  
Renal Function ◽  
Life Span ◽  
Biological Effects ◽  
Somatic Growth ◽  
Spatiotemporal Pattern ◽  
Urinary Proteins ◽  
Growth And Survival ◽  
Major Urinary Proteins ◽  
Igf I ◽  
Liver And Kidney

Abstract Activins βA and βB (encoded by Inhba and Inhbb genes, respectively) are related members of the TGF-β superfamily. Previously, we generated mice with an Inhba knock-in allele (InhbaBK) that directs the expression of activin βB protein in the spatiotemporal pattern of activin βA. These mice were small and had shortened life spans, both influenced by the dose of the hypomorphic InhbaBK allele. To understand the mechanism(s) underlying these abnormalities, we now examine growth plates, liver, and kidney and analyze IGF-I, GH, and major urinary proteins. Our studies show that activins modulate the biological effects of IGF-I without substantial effects on GH, and that activin signaling deficiency also has modest effects on hepatic and renal function. To assess the relative influences of activin βA and activin βB, we produced mice that express activin βB from the InhbaBK allele, and not from its endogenous Inhbb locus. InhbaBK/BK, Inhbb−/− mice have failure of eyelid fusion at birth and demonstrate more severe effects on somatic growth and survival than either of the corresponding single homozygous mutants, showing that somatic growth and life span are supported by both activins βA and βB, although activin βA plays a more substantial role.

Biological Effects of Irradiation with Thermal Neutrons on Boll Weevils Fed Boric Acid Containing Boron-101

1971 ◽  
Vol 64 (5) ◽  
pp. 1002-1008 ◽  
Author(s):  
H. M. Flint ◽  
E. L. Walk ◽  
W. Klassen ◽  
D. Greenberg
Keyword(s):  
Boric Acid ◽  
Biological Effects ◽  
Thermal Neutrons

scholarly journals A Comparison of Biological Effects between Thermal Neutrons and X-rays on Rice Seeds.

1958 ◽  
Vol 8 (1) ◽  
pp. 37-45 ◽  
Author(s):  
Takane MATSUO ◽  
Hikoyuki YAMAGUCHI ◽  
Akihiko ANDO
Keyword(s):  
Biological Effects ◽  
Thermal Neutrons ◽  
X Rays ◽  
Rice Seeds
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