Karyometric and cytophotometric study of hepatocyte nuclei of frogs exposed to cold and prolonged starvation

1966 ◽  
Vol 75 (1) ◽  
pp. 240-249 ◽  
Author(s):  
Marvin R. Alvarez ◽  
Ronald R. Cowden
Keyword(s):  
Prolonged Starvation ◽  
Cytophotometric Study

Physiologische Bedeutung der „Stringent Control“ bei Escherichia coli unter extremen Hungerbedingungen / Stringent Control and Starvation Survival in Escherichia coli

1989 ◽  
Vol 44 (9-10) ◽  
pp. 838-844 ◽  
Author(s):  
H. Mach ◽  
M. Hecker ◽  
I. Hill ◽  
A. Schroeter ◽  
F. Mach
Keyword(s):  
Escherichia Coli ◽  
Amino Acids ◽  
Amino Acid ◽  
Protein Turnover ◽  
Stringent Response ◽  
Phosphate Starvation ◽  
Pleiotropic Effects ◽  
Prolonged Starvation ◽  
Stringent Control ◽  
Starvation Survival

The viability of three isogenic relA+/relA strain pairs of Escherichia coli (CP78/CP79; NF 161/ NF162; CP 107/CP 143) was studied during prolonged starvation for amino acids, glucose or phosphate. After amino acid limitation we found a prolonged viability of all relA+ strains which synthesized ppGpp. We suggest that some ppGpp-mediated pleiotropic effects of the stringent response (e.g. glykogen accumulation, enhanced protein turnover) might be involved in this prolongation of survival. After glucose or phosphate starvation there was no difference in the relA+/relA strains either in the ppGpp content or in the survival.

scholarly journals On the adaptation of ticks to the habits of their hosts

Parasitology ◽  
1911 ◽  
Vol 4 (1) ◽  
pp. 46-67 ◽  
Author(s):  
George H. F. Nuttall
Keyword(s):  
Larval Stage ◽  
Feeding Habits ◽  
Small Aperture ◽  
Loss Of Life ◽  
Primitive Type ◽  
Prolonged Starvation

A consideration of the facts presented in the foregoing pages appears to warrant certain conclusions which must, however, be regarded in part as provisional and subject to revision when our knowledge of the various species of ticks has become more extended. The views here expressed may prove of practical use in the study of the Ixodidae.The Argasidae represent the relatively primitive type of ticks because they are less constantly parasitic than are the Ixodidae. Their nymphs and adults are rapid feeders and chiefly infest the habitat of their hosts. In certain Argasidae (O. moubata and O. savignyi) the disadvantage of their possessing an “active” larval stage has resulted in the development of an “inactive” larva, i.e. the young nymph being the first to suck blood. In O. megnini we have a considerable adaptation brought about by the difficulty there must be in the tick entering the small aperture of the ear more than once. Owing to the Argasidae infesting the habitats of their hosts, their resistance to prolonged starvation and their rapid feeding habits, they do not need to bring forth a large progeny, because there is less loss of life in the various stages, as compared to Ixodidae, prior to their attaining maturity.The Ixodidae are more highly specialized parasites than the preceding. The majority are parasitic on hosts having no fixed habitat and consequently all stages, as a rule, occur upon the host. In the genus Ixodes we find an adaptation of certain species according to the habits of the hosts upon which they are parasitic. In the species which usually occur upon wandering hosts both sexes are found upon the host, whereas in other species which occur on hosts possessing more or less fixed habitats the males are rarely or never found upon the host. The males of species of Ixodes, both sexes of which occur upon the host, are characterized, as a rule, by the possession of hypostomes with prominent teeth, the reverse being the case in forms wherein the males do not occur upon the host. Where species occur upon a wandering host it is essential, for their propagation in nature, that both sexes should be carried about upon the host.

Adaptation to prolonged starvation in the rat: curtailment of skeletal muscle proteolysis

1981 ◽  
Vol 241 (4) ◽  
pp. E321-E327 ◽  
Author(s):  
M. N. Goodman ◽  
M. A. McElaney ◽  
N. B. Ruderman
Keyword(s):  
Skeletal Muscle ◽  
Protein Synthesis ◽  
Muscle Protein ◽  
Muscle Protein Synthesis ◽  
Early Event ◽  
Body Protein ◽  
Fed State ◽  
Prolonged Starvation ◽  
Obese Rats ◽  
Old Rats

Previous studies have established that 16-wk-old nonobese and obese rats conserve body protein during prolonged starvation. To determine the basis for this, protein synthesis and degradation in skeletal muscle were evaluated in the isolated perfused hindquarters of these rats, in the fed state and when starved for 2, 5, 10, and 11 days. Rats aged 4 and 8 wk were used as a comparison. The results indicate that the response to starvation depends on several factors: the age of the rat, its degree of adiposity, and the duration of the fast. An early event in starvation was a decline in muscle protein synthesis. This occurred in all groups, albeit this reduction occurred more slowly in the older rats. A later response to starvation was an increase in muscle proteolysis. This occurred between 2 and 5 days in the 8-wk-old rats. In 16-wk-old rats it did not occur until between 5 and 10 days, and it was preceded by a period of decreased proteolysis. In 16-wk-old obese rats, a decrease in proteolysis persisted for upwards of 10 days and the secondary increase was not noted during the period of study. The data suggest that the ability of older and more obese rats to conserve body protein during starvation is due, in part, to a curtailment of muscle proteolysis. This adaptation seems to correlate with the availability of lipid fuels.

Performance and recovery of nitrifying biofilm after exposure to prolonged starvation

Chemosphere ◽  
2021 ◽  
pp. 133323
Author(s):  
Alessandro di Biase ◽  
Daniel Flores-Orozco ◽  
Rakesh Patidar ◽  
Maciej S. Kowalski ◽  
Pouria Jabari ◽  
...  
Keyword(s):  
Prolonged Starvation

PSYMCOLOGIC EFFECTS OF PROLONGED STARVATION IN EXTREME OBESITY

1970 ◽  
Vol 63 (3) ◽  
pp. 276-279
Author(s):  
Neil Solomon ◽  
Dietrich Blumer ◽  
Frederick F. Converse
Keyword(s):  
Extreme Obesity ◽  
Prolonged Starvation

scholarly journals Starvation Survival and Biofilm Formation under Subminimum Inhibitory Concentration of QAMs

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Sanjay Kumar Tiwari ◽  
Suping Wang ◽  
Yannan Huang ◽  
Xuedong Zhou ◽  
Hockin H. K. Xu ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Biofilm Formation ◽  
Acid Production ◽  
Inhibitory Concentration ◽  
Lactic Acid Production ◽  
Oral Bacteria ◽  
Laser Scanning Microscopy ◽  
Prolonged Starvation ◽  
Survival And Development ◽  
Development Of Tolerance

Quaternary ammonium methacrylates (QAMs) are useful antimicrobial compounds against oral bacteria. Here, we investigated the effects of two QAMs, dimethylaminododecyl methacrylate (DMADDM) and dimethylaminohexadecyl methacrylate (DMAHDM), on biofilm formation, survival and development of tolerance by biofilm, and survival and development of tolerance against QAMs after prolonged starvation. Enterococcus faecalis (E. faecalis), Streptococcus gordonii (S. gordonii), Lactobacillus acidophilus (L. acidophilus), and Actinomyces naeslundii (A. naeslundii) were used. Minimum inhibitory concentration (MIC) of QAMs against multispecies biofilm was determined. Biofilm formed under sub-MIC was observed by crystal violet staining and confocal laser scanning microscopy (CLSM). Metabolic activity was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and lactic acid production measurement. Development of tolerance was determined by MIC values before and after exposure to QAMs or after prolonged starvation. It was found that E. faecalis and S. gordonii could survive and form biofilm under sub-MIC of QAMs. Lactic acid production from biofilms formed under sub-MIC was significantly higher than control specimens ( p < 0.05 ). The exposure to sub-MIC of QAMs promoted biofilm formation, and prolonged starvation or prolonged contact with sub-MIC helped bacteria develop tolerance against killing by QAMs.

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