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1.
  • 1.1. The behaviour of the tRNA population during the acclimatization process was studied, examining the intracellular levels of aminoacylated-tRNAs in livers from summer and winter adapted carps (Cyprinus carpio).
  • 2.2. The in vivo content of Val-tRNA, Ala-tRNA and Met-tRNA decreased significantly during the summer season, in which Val was 80%, Ala 47% and Met 54% with respect to the values attained in winter.
  • 3.3. The half-life for the nonenzymic deacylation showed significant variations for the two populations of aminoacyl-tRNA obtained from summer and winter acclimatized fish.
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2.
  • 1.1. Lipid concentrations and lecithin:cholesterol acyltransferase (LCAT) activity in the plasma Tropidurus torquatos were remarkably variable.
  • 2.2. Both lipid levels and LCAT activity were highest for lizards collected during the early rainy season (March–April) than during other seasons, and were higher for females than for males.
  • 3.3. Plasma lipid levels and LCAT activity were significantly and inversely correlated with body weight (age) of male lizards, this being associated with an apparent change to an herbivorous diet in older males.
  • 4.4. During prolonged fasting, plasma lipid levels and lecithin:cholesterol acyltransfer (LCAT) and hepatic phospholipids were markedly reduced.
  • 5.5. LCAT activity in plasma of fasted and non-fated lizards was significantly correlated with the molar proportion of PC to UC, suggesting that the apparent low LCAT in plasma of fasted lizards is partly due to depletion of PC in the lipoprotein substrates.
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3.
  • 1.1. The lipid and fatty acid composition from the plasma and hemocytes in Octopus tehuelchus at different stages of sexual development, was determined.
  • 2.2. The highest content of lipids was found in females engaged in egg development, and the lowest in post-spawning and brooding females. Highest levels occurred during the autumn season in both sexes.
  • 3.3. Changes were mainly due to triacylglycerols and diacylglyceryl ethers.
  • 4.4. The plasma fatty acid composition did not demonstrate significant changes at different stages of maturation. The arachidonic acid (20:4 ω 6) was present at surprisingly high levels.
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4.
  • 1.1. Since glucose is one of the main energetic substrates for general metabolic processes in crustaceans, analysis of carbohydrate levels can furnish information on the energy metabolism of intact animals during osmoregulation.
  • 2.2. Different groups of Chasmagnathus granulata were transferred to different salinities (0 and 40%), and the glucose and glycogen concentrations in blood, gills, muscle and hepatopancreas were determined at the beginning of the experiment and 24, 72, 168 and 360 hr after the salinity changes.
  • 3.3. Differences in tissues carbohydrate levels were observed between summer and winter, that reflected differences in reserve mobilization.
  • 4.4. In the summer, hypo- and hyperosmotic shocks induced an increase in carbohydrate levels in almost all tissues studied, indicating gluconeogenesis.
  • 5.5. In the winter, a carbohydrate mobilization occurred only in the gills and hepatopancreas after both osmotic shocks.
  • 6.6. Thus, the substrate reserve used for energy production required for osmoregulation seems to be dependent on the season and tissues.
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5.
  • 1.1. Seasonal acclimatization effects on oxygen consumption, body temperature, and body weight were evaluated in three different experimental groups of Dipodomys panamintinus.
  • 2.2. Body weights of wild field as well as captive animals housed in outdoor sand cages were maximum in winter and lowest in summer for both sexes.
  • 3.3. Mean oxygen consumption was maximum in winter and lowest during spring in both sexes of the wild field and captive exposed groups.
  • 4.4. Neither weight nor oxygen consumption of indoor control animals varied with the seasons.
  • 5.5. No significant differences in body temperatures were observed during either the fall or winter seasons.
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6.
  • 1.1. Seasonal changes in the accumulation of end products after 48 hr of exposure to air and in the composition of the free amino acid pool were studied in Mytilus edulis.
  • 2.2. The accumulation levels of succinate and acetate showed only weak seasonal changes.
  • 3.3. Conversion of succinate to propionate was high in summer and virtually zero in winter
  • 4.4. Alanine and most other free amino acids were present in relatively high concentrations in summer and early autumn and reached minimal values in winter and early spring.
  • 5.5. Exceptions were glutamate, aspartate and taurine, which showed hardly an season related changes and glycine, which changed inversely to the majority of the free amino acids.
  • 6.6. The anaerobic formation of alanine was inversely proportional to the endogenous concentration.
  • 7.7. The only other free amino acids affected by anaerobiosis were glutamate and aspartate, which respectively increased and decreased under these conditions.
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7.
  • 1.1. Seasonal changes of circulating blood parameters of Natrix n. natrix were evident and involved both sexes to the same extent.
  • 2.2. A significant decrease in red cell count, haematocrit and haemaglobin concentration in the mating period, and an increase in those parameters and mean cell volume in autumn were observed, and haemodilution during winter torpor.
  • 3.3. The changes during the breeding season had probably a hormonal background; in winter, they resulted first of all from a decreased erythropoietic activity and, to a lesser extent, from an increased red blood cell breakdown rate. However, the possibility that some erythrocytes were withdrawn from the circulation cannot be excluded.
  • 4.4. Winter lymphocytopenia, eosinocytopenia and neutrophilic granulocytosis in females during egg laying were expressions of changes of leucocyte formula.
  • 5.5. Seasonal cyclicity was found only with respect to the white cell count in males and the eosinophile fraction in males and females.
  • 6.6. Probable reasons for, and mechanisms of the changes in blood composition are discussed.
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8.
  • 1.1. Digestive gland and mantle fatty acids were studied in spring and summer in the bivalve Macoma balthica off the southern coast of Finland. The presence of lipids was also examined histochemically in various clam tissues.
  • 2.2. the neutral lipid content of the digestive gland increased ca 4.5-fold during the annual growth period.
  • 3.3. Neutral lipid fatty acids of the digestive gland, of which palmitoleic, eicosapentaenoic and palmitic acids were predominant, were clearly distinguished from phospho- and glycolipid fatty acids.
  • 4.4. The degree of unsaturation of phospholipid fatty acids was higher in the cold season both in the digestive gland and mantle, mainly due to the titer of eicosapentaenoic acid.
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9.
  • 1.1. Body weight, the weight of the hepatopancreas, protein content in the hepatopancreas and phosphatase activity at pH 8.5 in the hepatopancreas are great in spring and summer, and decrease during autumn and winter.
  • 2.2. Phosphatase activity at pH4.5 is the same throughout the year.
  • 3.3. Participation of acid phosphatases in extracellular and intracellular digestion and participation of alkaline phosphatases in food resorption and calcium deposition are postulated.
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10.
  • 1.1. The extent of anaerobic energy production of Arenicola marina during low tide is dependent on the season and on the locality in the intertidal.
  • 2.2. Anaerobic energy production was only found: (a) in animals from sediments, which fall dry for several hours; (b) in summer and autumn, but not in winter and spring.
  • 3.3. A correlation between the extent of anaerobic energy production and the development of gametes was demonstrated.
  • 4.4. The process of spawning represents a great stress to the animals. At this time the ability of Arenicola marina to survive anaerobic conditions was reduced drastically.
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11.
  • 1.1. The effects of seasonal variation on the carbohydrate and lipid metabolism of the Chasmagnathus granulata were investigated.
  • 2.2. Glycemia is high in winter and summer and low in spring and fall.
  • 3.3. The glycogen content in the hepatopancreas and muscle is higher in fall and winter, and decreases during spring and summer.
  • 4.4. The muscle lipids are higher in summer, and decrease during fall and winter whereas hepatopancreas lipids are higher except in the fall.
  • 5.5. The crabs show change in the metabolic pattern of lipids and carbohydrates during the seasons of the year.
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12.
  • 1.1. Properties of acetylcholinesterase (AChE, EC 3.1.1.7) from Apis mellifera head were studied during pupal development and at the adult stage.
  • 2.2. During post-embryonic development, tissue and specific activities were closely related and increased to reach a maximum value at emergence and at last pupal stage, respectively.
  • 3.3. In adults, AChE activity was weaker in foragers than in emerging bees.
  • 4.4. The membrane form occurred in adult bees as well as in pupae whereas the soluble enzyme only appeared from Pd pupal stage.
  • 5.5. The proportion of soluble and membrane forms fluctuated during late development but, in all cases, the percentage of the soluble form remained less than 10% of total AChE activity.
  • 6.6. At all post-embryonic stages, the membrane form was sensitive to the action of phosphatidylinositol-specific phospholipase C (PI-PLC) and was converted into a hydrophilic enzyme.
  • 7.7. In adult bees, the sensitivity to PI-PLC depended on the season. In summer, about 60% of the membrane activity could be solubilized by PI-PLC vs only 5% in winter.
  • 8.8. The sensitivity of AChE to pirimicarb varied with the developmental stage.
  • 9.9. In foraging bees, AChE was more susceptible to pirimicarb than in emerging bees. This difference of sensitivity to carbamate was abolished after removal of the membrane anchor either by mild trypsin digestion of PI-PLC treatment.
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13.
  • 1.1. The effects of photoperiod and pinealectomy on plasma corticoid levels in the goldfish (Carassius auratus) were examined.
  • 2.2. Plasma corticoid levels differed in goldfish maintained under different photoperiod regimes, but this response varied seasonally.
  • 3.3. Pinealectomy altered the effects of photoperiod on plasma corticoid levels but this effect varied with season.
  • 4.4. Plasma corticoid levels were correlated with ovarian activity. The effects of photoperiod on plasma corticoid levels appear to be related to the influence of light on reproduction.
  • 5.5. The alteration of plasma corticoid levels in pinealectomized fish may be due to the role this organ plays in mediating photoperiod effects on gonadal activity.
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14.
  • 1.1. Progesterone levels in Mytilus edulis males and females during the annual reproductive cycle were analysed in the whole animal and in the gonads using gas-liquid chromatography and radioimmunoassays.
  • 2.2. The high hormone levels in the whole animal were observed in July and October, coincident with the main spawning seasons.
  • 3.3. The levels of progesterone in gonad extracts also show a maximum in summer (July).
  • 4.4. The patterns of the progesterone levels in males and females throughout the annual reproductive cycle are similar.
  • 5.5. These data are discussed in relation to the role of progesterone in the regulation of sex-specific processes, particularly gametogenesis.
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15.
  • 1.1. Aspects of ruminant-like metabolism were examined in the hyrax Procavia capensis.
  • 2.2. High concentrations of volatile fatty acids occurred in the cardiac stomach with a predominance of acetic and lactic acids.
  • 3.3. Acetic (69%), propionic (22%) and butyric (8%) acids occurred in highest concentrations in the proximal caecum, with appreciable amounts in the proximal colon, distal caecum and appendices.
  • 4.4. The depot fat contained high proportions of unsaturated C18 (linoleic and linolenic) acids.
  • 5.5. The glucose level in the plasma was within the range established for non-ruminant herbivores.
  • 6.6. The possibility of silage-like fermentation occurring in the cardiac stomach is discussed.
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16.
  • 1.1. Lipid, glucose and glycogen concentrations were measured in different tissues of the crab Chasmagnathus granulata during emersion.
  • 2.2. After 6 hr of emersion no reduction in the total amount of carbohydrates was found to occur, suggesting that a general metabolic arrest was taking place.
  • 3.3. A transitory increase in haemolymphatic glucose and lipid levels was observed. Possible causes are therefore discussed in relation to changes in the flux of substrates for energy production.
  • 4.4. The mobilization of carbohydrates and lipids to the gills, observed only during summer, may be concerned with energy supplying for ionic regulation.
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17.
18.
  • 1.1. Aspects of the physiology of two southern African scorpions have been examined. The scorpions are the large desert species Parabuthus villosus (Peters) (Buthidae) and the more mesic, burrowing species Opisthophthalmus capensis (Herbst) (Scorpionidae).
  • 2.2. Evaporative water losses were higher in Opisthophthalmus at all temperatures.
  • 3.3. Analysis of haemolymph during prolonged desiccation showed good osmotic and ionic regulation in Parabuthus but no regulation in Opisthophthalmus.
  • 4.4. Oxygen consumption of Parabuthus was measured after acclimation to 10 and 30°C. Metabolic rates were extremely low but there was no metabolic compensation to increased temperatures.
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19.
  • 1.1. The relationship between gonadal maturation and serum calcium levels was studied in hake, Merluccius gayi gayi, and killifish, Fundulus heteroclitus.
  • 2.2. Sexually mature male and female hake were sampled in the field throughout the year. Serum calcium was higher in all sexually mature fish regardless of the season, indicating a gonadal effect on serum calcium levels.
  • 3.3. Male killifish adapted to constant laboratory conditions showed no change in serum calcium at different stages of gonadal maturation. Castration also had no effect. However, clear relationships exist between testicular maturation and serum inorganic phosphate, percentage hematocrit and liver sizes.
  • 4.4. Such species differences are discussed.
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20.
  • 1.1. The phenoloxidase activity, protein and carbohydrate levels were studied for 24 hr in the hemolymph of the migratory grasshopper, Melanoplus sanguinipes after artificial wounding of the insect cuticle or the injection of Beauveria bassiana conidia.
  • 2.2. Injection or wounding induced a primary response and phenoloxidase activity was found to increase within 10–60 min. The values for phenoloxidase activity in viable B. bassiana-injected insects exhibited a secondary response, i.e., an increase 24 hr after injection.
  • 3.3. In wounded insects and those injected with inactivated conidia, the phenoloxidase activity receded after the initial increase and remained at low levels.
  • 4.4. Protein concentrations in the hemolymph increased immediately after infection and wounding and returned to basal levels during the course of the experiment.
  • 5.5. Injection of viable B. bassiana resulted in a gradual increase in the protein concentrations between 12 and 24 hr.
  • 6.6. There was no apparent change in the carbohydrate levels in either B. bassiana-infected or wounded insects.
  • 7.7. These results are discussed in relation to their possible role(s) and interrelationships in the immune response to infection or wounding. Furthermore, we suggest that a “factor” is released after mechanical injury of the integument.
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