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1.
  • 1.1. A membrane glycoprotein was isolated from Tetrahymena surface membrane with properties similar to mammalian erythrocyte glycoprotein.
  • 2.2. This membrane glycoprotein had a specific acitivity less than whole membrane at various time intervals up to 40 hr.
  • 3.3. In double labelling experiments, glucosamine contributed a greater degree of the labelling of this glycoprotein than did amino acids.
  • 4.4. Greater incremental increases in the glucosamine radioactivity over amino acids at the longer time intervals suggests that the carbohydrate and protein moieties may have independent metabolic pathways.
  • 5.5. When Tetrahymena was grown in proteose peptone-tryptone in the presence of labelled amino acid, the specific activity of the surface membrane was less than one-tenth of the specific activity obtained in defined growth media. Under these same conditions, there were only slight changes in the specific activities of glucosamine in the membrane.
  • 6.6. Data is presented suggesting independent synthesis of the protein and oligosaccharide from different pools.
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2.
  • 1.1. Haemolymph volume decreases during the initial 16 hr post-ecdysial period, increases after water ingestion and subsequently drops until the inter-ecdysial level is reached.
  • 2.2. Total body water follows a similar pattern, but the changes are not as pronounced.
  • 3.3. Tissue water is inversely proportional to the total body water.
  • 4.4. Soluble cuticle protein declines throughout the initial 16 hr period while both β-glucosidase and alkaline phosphatase activity is lost within 6 hr after ecdysis.
  • 5.5. Dehydration of the cuticle also occurs during the immediate 6 hr post-ecdysial period.
  • 6.6. These data suggest that the formation of the protein-insoluble matrix is linked with water loss.
  • 7.7. Water removal may decrease the distance between molecules allowing specific reactions to take place.
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3.
  • 1.1. Some effects of restricting feed intake for 96 or 168 hr were determined in male Nubian goats.
  • 2.2. Goats restricted for 96 hr lost 11.6% of their body weight, and goats restricted for 168 hr lost 19.8%.
  • 3.3. Feed restriction for up to 168 hr did not produce significant effects on the heart rate, respiratory rate or rectal temperature.
  • 4.4. Haemoglobin concentration, packed cell volume and erythrocyte number were all decreased by feed restriction. There was also a tendency towards eosinopenia and lymphopenia.
  • 5.5. Feed restriction for 96 or 168 hr raised the plasma activity of aspartate transaminase, and did not affect significantly cholinesterase activity. Plasma amine oxidase activity was significantly reduced in goats restricted for 168 hr.
  • 6.6. Feed restriction produced significant increases in the blood or plasma concentrations of lactate. pyruvate, non-esterified fatty acids, cholesterol, ketone bodies and bilirubin.
  • 7.7. Significant decreases were found in the concentrations of total protein and calcium.
  • 8.8. No significant changes were observed in the plasma concentrations of glucose, sodium or potassium.
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4.
  • 1.1. The distribution of radiolabel from L-leucine [14C-UL] and D-glucose [14C-UL] was measured in the sea star Asterias rubens at 1, 6 and 24 hr after oral administration.
  • 2.2. Incorporation of the label from both compounds was observed in pyloric caeca, coelomocytes and ovaries even after an incubation time of 1 hr.
  • 3.3. Highest incorporation from both precursors was found in proteins, while substantial radioactivity was present in the amino acids, organic acids and neutral components. Lipids were hardly labelled from leucine and only slightly from glucose.
  • 4.4. Radioactivity in proteins and lipids increased with increasing incubation time. No significant differences were found in the distribution patterns of radiolabel during the reproductive cycle.
  • 5.5. The data obtained are discussed in terms of current knowledge on the translocation of nutrients in echinoderms.
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5.
  • 1.1. To evaluate changes in high-energy phosphate metabolism in the water scorpion (Ranatra chinensis) under restraint and cold water-warm water stresses, in vivo [31P]NMR spectra were obtained.
  • 2.2. Under restraint stress, arginine phosphate (Arg-P) decreased by 10% after 1 hr and remained at that level thereafter, while β-ATP showed negligible changes over 6 hr.
  • 3.3. As the water temperature gradually increased or decreased, the relative concentration of Arg-P decreased due to enzyme regulation.
  • 4.4. Repeated cold water-warm water stress, which consisted of repeated 15 min exposures to cold water (5°C) followed by 15 min exposures to warm water (30°C) caused distinct decreases in Arg-P and β-ATP concentration. These decreases were dependent on the frequency of exposure.
  • 5.5. Phosphomonoesters (PME) increased not only with restraint stress but also with cold water-warm water stress.
  • 6.6. The effect of cold water-warm water stress on high-energy phosphate metabolism was greater than that of restraint stress.
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6.
  • 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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7.
  • 1.1. Oestradiol administration in castrated rats resulted in an increased activity of the cholesterolα-hydroxylase and a decreased activity of the drug oxidase enzyme systems.
  • 2.2. Aqueous solutions of oestradiol (up to 25·10−6M) incubated in vitro with microsomes, binds into the microsomal membrane framework reducing the activity of both enzyme systems.
  • 3.3. The specific activity of cholesterol 7α-hydroxylase. drops after 3 hr preincubation with oestradiol to at least 70% of its original value.
  • 4.4. Actinomycin D and cycloheximide administration reduced the oestradiol-induced and control cholesterol 7α-hydroxylase activity to the same level, 6 hr after the injections.
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8.
  • 1.1. An acid phosphatase from barley seeds germinated for 120 hr, that is not affected by the presence of cycloheximide, is a glycoprotein.
  • 2.2. The enzyme has an optimum pH 4.9 and a mol. wt of 57,000 as determined by SDS-gel electrophesis.
  • 3.3. The main sugar is galactose amounting to one half of the protein and it is as either mono or disaccharide.
  • 4.4. Serine and glycine predominate and hydroxyproline is absent.
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9.
  • 1.1. The oxygen consumption of the marine teleost, Lichia amia was investigated under controlled laboratory conditions.
  • 2.2. The routine oxygen consumption showed a strong circadian rhythm with the fish being mainly active during the light period.
  • 3.3. The specific mass exponent (dimension: μg O2/g/hr) is temperature independent and ranges from 0.27–0.29.
  • 4.4. Starving the fish results in a mean decrease in active, routine and standard oxygen consumption of 21%, 24% and 20%, respectively.
  • 5.5. Feecling led to an increase in the oxygen consumption of the teleosts, with the mean metabolic rate over the 24 hr that followed, being 58% and 50% higher for fish that had been starved for 162hr and 40 hr, respectively.
  • 6.6. Apparent SDA showed some variation and ranged from 6.0 to 35.5%.
  • 7.7. The results obtained are generally in agreement with those recorded for other teleosts.
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10.
  • 1.1. Albumin purified from rhesus monkey (MSA) shows immunological cross-reactivity with human serum albumin (HSA) by RIA.
  • 2.2. The amino-terminal sequence of MSA shows a high degree of homology to HSA.
  • 3.3. Thirty minutes after injection of radioactive leucine directly into the portal vein, albumin was purified chemically from the liver, kidneys and serum.
  • 4.4. At this time, 15% of the label was incorporated into liver homogenate protein.
  • 5.5. A highly labelled immunoreactive albumin form was purified from liver to constant specific radioactivity and separated from tissue and serum albumin.
  • 6.6. The specific radioactivity of this proalbumin was 36-times higher than the specific radioactivity of albumin in liver tissue.
  • 7.7. These similarities to HSA suggest that this non human primate species can serve as a useful model of human albumin synthesis in vivo.
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11.
  • 1.1. Two major glycoprotein components were released in vitro by rat gastric mucosal cells after 4 hr incubation with radioisotopes: a high molecular weight fraction with the characteristics of a fucomucin and a low molecular weight fraction, the latter having a higher specific radioactivity than the former.
  • 2.2. Pulse chase experiments indicate that several low and high molecular weight glycoproteins are synthesized simultaneously with no precursor-product relationship between them.
  • 3.3. Common antigenic determinants, specific to the stomach were found on the 2 fractions, using immunofluorescence, both fractions appeared to be present in the same cells.
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12.
  • 1.1. The distribution of different phospholipids and the repartition of fatty acids extracted from hemolymph of crab Carcinus maenas are analysed.
  • 2.2. The action of the temperature on the lipid composition is also determined: an increase of content of PE and a slight rise of the degree of unsaturation of fatty acids are found at lower temperatures.
  • 3.3. The specific radioactivity of total phospholipids, phosphatidyl-choline and phosphatidylethanolamine from hemolymph of Carcinus maenas is studied from two radioactive precursors (32Phosphorus and 3H]ethanolamine). Results suggested that the conversion of PE into PC by methylation could take place in hepatopancreas of Carcinus maenas.
  • 4.4. The specific radioactivity of phospholipids from these two same radioactive compounds is increased following a variation in the environmental temperature.
  • 5.5. The composition of hemolymph lipids could be a direct reflection of the lipid metabolism of the hepatopancreas and that the temperature alters the rate of the phospholipid exchange between hepatopancreas and hemolymph.
  • 6.6. It is suggested that these lipid alterations occur in order to permit crab Carcinus maenas to support large changes in environmental temperatures.
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13.
  • 1.1. Eel were exposed to a sublethal concentration of lindane (0.335 ppm) for 6, 12, 24, 48, 72 and 96 hr.
  • 2.2. Concentrations of glycogen, glucose, lactate, pyruvate and lipids were determined in gill tissue after lindane exposure.
  • 3.3. Gill glycogen descreased and glucose levels increased at 6 hr of treatment, lactate and pyruvate concentration increased between 6 and 48 hr. Total lipid values decreased between 6 and 24 hr; thereafter, the levels increased up to 72 hr of exposure.
  • 4.4. Clear changes were found in all parameters tested in gill tissues. The observed effects of lindane on metabolism in fish are discussed in relation to acute stress syndrome.
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14.
  • 1.1. Any diurnal rhythms in the hepatic specific activities of some enzymes of carbohydrate, lipid and amino acid metabolism were studied over a 36 hr period in immature domestic fowl subjected to 12 hr light: 12 hr dark.
  • 2.2. Only ATP-citrate lyase exhibited a diurnal fluctuation in metabolism having a higher specific activity in the light period than in the dark period.
  • 3.3. The results are discussed in relation to the diurnal rhythm in energy metabolism observed in domestic fowl.
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15.
  • 1.1. Gelatin, extracted by autoclaving animals after removing free amino acids with 80% ethanol, ranges from 43% of total protein in the scyphistoma to 80% in the adult medusa.
  • 2.2. Glutamic acid is predominant in gelatin from the scyphistoma, whereas adult gelatin is more typical of collagens from other cnidarians.
  • 3.3. Glycine, hydroxylysine and hydroxyproline are all lower than in other cnidarian collagens, suggesting a low degree of cross-linking in this species.
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16.
  • 1.1. A comparison of proteolytic and protease inhibitory activity, and ecdysteroid levels in body fluids was made between normal larvae of the flesh fly, Sarcophaga bullata, and those that had been water-stressed for two days.
  • 2.2. The course of proteolytic activity in water stressed flies decreases 6 hr after beginning the experiment and remains low in comparison with control flies.
  • 3.3. The course of protease inhibitors exhibits a mirror image pattern to proteases.
  • 4.4. Ecdysteroid pattern shows two peaks in control animals: minor at 24 hr and major at pupariation, in experimental animals: at 1 hr, at 6 hr and at white pupal stage.
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17.
  • 1.1. Membrane bound granules were isolated from homogenates of the foot of Mytilus californianus and shown to correspond to the ellipsoid collagen granules described by Tamarin & Keller (1972).
  • 2.2. Protein was extracted from the purified granules by standard procedures for preparation of collagen and its amino acid composition was compared with that of vertebrate collagen and different parts of the byssus secreted by glands in the mussel's foot.
  • 3.3. Hydrolysates of collagen extracted from granules contained approximately 8 mole % hydroxyproline and 33 mole % glycine and were similar in composition to byssus threads.
  • 4.4. Analyses of other parts of the byssus indicated that they contained collagen in addition to other protein components.
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18.
  • 1.1.|The body temperature and activity of cats exhibit two-peak patterns during the 24 hr period.
  • 2.2.|The two peaks are retained when the temperature and activity are permitted to freerun.
  • 3.3.|A third prominent peak appears in the actograms in cats in the main colony, induced by the presence of humans.
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19.
  • 1.1. Five adult, female alligators (Alligator mississippiensis) were captured at night during the breeding season, and a blood sample taken within 5 min of capture.
  • 2.2. The alligators were physically restrained (tied to boards) and additional blood samples taken at 4, 8, 12, 16, 22, 28, 38, and 48 hr after capture. After the last blood sample was collected the animals were released.
  • 3.3. Plasma estradiol-17β and corticosterone were measured by radioimmunoassay. Estradiol declined significantly from initial values by 22 hr post capture, but remained unchanged for 48 hr.
  • 4.4. Plasma corticosterone rose from a mean of 0.8 ng/ml at capture to 12.6 ng/ml after 4 hr. Corticosterone continued to rise up to 16 hr then declined after 22 hr. From 28 until 48 hr corticosterone again increased significantly.
  • 5.5. These results demonstrate that acute stress in female alligators causes significant suppression of plasma estradiol and a biphasic pattern of corticosterone secretion.
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20.
  • 1.1. The total amount of DNA present in L5178Y cells treated with antiserum in the absence of complement was decreased whereas the rate of incorporation of [3H]thymidine into DNA during a 1 hr pulse was increased as compared with those of controls.
  • 2.2. This increase in specific activity of [3H]thymidine in the DNA of antiserum-treated cells appeared to be due, at least in part, to an increase in thymidine kinase activity.
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