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1.
  • 1.1. Urate spherules obtained from three cockroach species have been isolated, purified and examined by scanning electron microscopy, atomic absorption, i.r. and Kjeldahl analysis.
  • 2.2. Purified spherules exposed to ionic environments may change from a smooth to a textured form.
  • 3.3. Ion analysis confirmed that the spherules are high in K+ and low in Na+.
  • 4.4. All preparations from the cockroach tissues diaplayed similar i.r. spectra, but were dissimilar to those of uric acid and urate salt standards.
  • 5.5. It appears that there is a distinct pattern or mechanism by which the cockroach urates are deposited in the spherule matrix.
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2.
  • 1.1. Exposure of human caeruloplasmin, an acute phase protein with antioxidant properties, to a mixture of xanthine/hypoxanthine and xanthine oxidase as a source of reactive oxygen intermediates decreased its ferroxidase and ascorbate oxidase activities and its ability to inhibit lipid peroxidation.
  • 2.2. Immunological reactivity was also altered.
  • 3.3. Exposure to hydrogen peroxide mimicked these effects.
  • 4.4. Exposure to low-intensity u.v. irradiation depressed caeruloplasmin's ability to inhibit iron-catalysed hyaluronic acid degradation.
  • 5.5. The results may explain the mechanism of the observed inactivation of caeruloplasmin within human rheumatoid synovial fluid.
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3.
  • 1.1. Responses of channel catfish (Ictalurus punctatus) swim-up fry to dietary calcium in soft (< 1 mg/1 as CaCO3) and hard (> 100 mg/1 as CaCO3) water were determined by feeding purified egg-white diets containing 0, 0.5, 1.0, or 2.0% calcium from CaCO3 for 8 weeks.
  • 2.2. Catfish fry fed the basal diet (0.03% Ca) in hard and soft water had lower whole-body ash and whole-body calcium concentrations but higher weight gain and survival than those fed calcium-supplemented diets.
  • 3.3. Fry in soft water generally had lower whole-body ash, whole-body calcium, and survival, as well as a higher incidence of spinal deformities than fry in hard water.
  • 4.4. Feeding higher levels of calcium to fry reared in soft water did not increase whole-body calcium levels or decrease spinal deformities to the levels observed for fry reared in hard water and fed supplemental calcium.
  • 5.5. These data indicate that calcium derived solely from dietary or environmental sources was not sufficient for optimum health of channel catfish fry.
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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. The urate, urea and ammonia content of the whole egg of the Japanese quail was measured in late incubation in eggs subject to different rates of water loss.
  • 2.2. High rates of water loss substantially increased egg urate content, but had little or no effect on urea or ammonia content.
  • 3.3. Allopurinol, an inhibitor of urate synthesis, reduced egg urate content to low levels, but produced no effect on urea content, and a small reduction in ammonia content.
  • 4.4. The urea concentration of the embryo was lower than in allantoic fluid.
  • 5.5. It is concluded that urate production by the avian embryo is primarily concerned with the modification of allantoic fluid composition.
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6.
  • 1.1. Indian River male broiler chickens growing from 7 to 28 days of age were fed diets containing 12, 18, 24 and 30% protein + 0 or 1 mg triiodothyronine (T3)/kg of diet to study energetic costs of lipogenesis and the use of various substrates for in vitro lipogenesis.
  • 2.2. De novo lipid and CO2 production were determined in the presence of [1-14C]pyruvate, [2-14q]pyruvate, [3-14C]pyruvate, [2-14C]acetate and [U-14C]alanine.
  • 3.3. Oxygen consumption was determined in mitochondrial preparations to estimate the energetic costs in expiants synthesizing lipid.
  • 4.4. Radiolabeled CO2 derived from [1-14C]pyruvate was used as an estimate of coenzyme A availability in liver expiants. Lipids derived from [2-14C]pyruvate, [2-14C]acetate and [U-14C]alanine estimate relative substrate efficiency.
  • 5.5. Labeled CO2 production from [1-14C]pyruvate was greatest in that group fed a 12% protein diet and least in the group fed a 30% protein diet.
  • 6.6. In addition, T3 increased CO2 production from [1-14C]pyruvate.
  • 7.7. The production of 14CO2 from the second carbon of pyruvate or acetate was increased by T3.
  • 8.8. The low-protein diet (12% protein) increased (P <0.05) lipogenesis.
  • 9.9. Adding T3 to the diets decreased carbon flux into lipid from all substrates, but increased CO2 production from all substrates without changing stage 3 and 4 respiration rates in mitochondrial preparations.
  • 10.10. These observations imply that coenzyme A availability may have regulated de novo lipogenesis in the present study.
  • 11.11. It was also concluded that previously noted effects of T3 on intermediary metabolism may involve metabolic pathways that do not involve changes in mitochondrial function.
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7.
  • 1.1. Experiments performed on isolated hepatocytes and perfused liver of starved chickens showed that gluconeogenesis from lactate, glycerol and fructose was inhibited by 22–100% on addition of urate precursors.
  • 2.2. The inhibition was associated with an increased rate of urate formation.
  • 3.3. 2,4-Dinitrophenol (40 μM), 2-bromooctanoate (2 mM) and 3-mercaptopicolinate (3MPA) (0.5 mM) were inhibitory with respect to gluconeogenesis but did not significantly affect the rate of urate formation.
  • 4.4. The possible interrelationships between gluconeogenesis and uricogenesis are considered in terms of a competition for ATP and for other metabolites between the two pathways.
  • 5.5. An interplay of both pathways at the level of anion transfer across the inner mitochondrial membrane is also discussed.
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8.
  • 1.1. Mineral balance was studied in meadow voles (Microtus pennsylvanicus) maintained in the laboratory.
  • 2.2. Urine and fecal Na+ contents of voles on low-Na+ diets were comparable to those reported for other herbivore species, but urine and fecal K levels were higher.
  • 3.3. Voles approached Na+ balance (input = output) on diets with Na+ content as low as 56 ppm.
  • 4.4. There was not a clearcut hypertrophy of the adrenal-gland zona glomerulosa in voles maintained on low-Na+ diets.
  • 5.5. Plasma K content and bone water content were higher in voles maintained on high-Na + vegetation diets, suggesting expansion of extracellular fluid volume.
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9.
  • 1.1. Groups of Luidia clathrata were fed maintenance level diets of Donax variabilis (50% protein by dry weight) or Penaeus duorarum (80% protein) or were starved.
  • 2.2. The NH4+ excretion rates for all treatments increased from 6.06 ± 2.55 to 14.39 ± 4.31 μg NH4+ − N/g dry wt per hr after 20 days.
  • 3.3. The urea excretion rate for all treatments was 1.25 ± 3.39 μg urea-N/g dry wt per hr for 56 days.
  • 4.4. The pyloric caecum index (percentage of wet body weight) decreased 16.5 and 73.4%, for Donax variabilis-fed and starved sea stars, respectively. The pyloric caecum index of Penaeus duorarum-fed sea stars increased 81.5%. The protein level of the pyloric caeca was 47.00 ± 4.14% of the dry weight for the fed animals and 37% for the starved animals.
  • 5.5. Increased NH4+ excretion rates with starvation or presumed maintenance diets appear to be due to tissue catabolism.
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10.
  • 1.1. The net absorption of protein, fatty acids, calcium and phosphate along the small intestine of the turkey (Meleagris gallopovo) was evaluated with the aid of 91Y as a reference substance.
  • 2.2. About 85% of the ingested protein was absorbed, with most of the absorption occurring in the duodenum and upper jejunum.
  • 3.3. The overall lipid absorption coefficient was around 90%, and was inversely related to the fatty acid chain length and saturation.
  • 4.4. Most of the lipid absorption occurred in the duodenum and jejunum.
  • 5.5. Calcium absorption also occurred in the duodenum and jejunum: its fractional rate decreased with calcium intake.
  • 6.6. Phosphate absorption occurred mostly in the duodenum and jejunum and its efficacy was only slightly affected by dietary phosphate intake.
  • 7.7. The high nutrient absorption in the turkey duodenum, relative to that of the chick (Gallus domesticus), was discussed.
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11.
  • 1.1. The present work deals with the effect of feeding hornets on moderate amounts of theophylline and allopurinol.
  • 2.2. The median survival time of hornets fed on allopurinol was greater than that of hornets fed on theophylline, while that of a control group fed on sugar solution alone was between the two drug-fed groups.
  • 3.3. The controlled-diet hornets, which were kept in the groups of 10, lived longer than hornets in groups of 20 or 40.
  • 4.4. Those fed on theophylline usually did not eat proteins, niether did they build cells, lay eggs nor engage in any social activity. They behaved rather like queen hornets during the winter diapause.
  • 5.5. Hornets fed on allopurinol built less cells and combs than did the controls. They were very aggressive, produced fewer eggs, attended less brood than did the controls and fed intensively on proteins (partly through cannibalism).
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12.
  • 1.1. The rates of oxygen consumption of five species of Gorgonacea were determined and their daily energy requirements for metabolism were estimated.
  • 2.2. Oxygen consumption rates varied between 0.15 and 0.76 mg O2 g organic matter−1 hr−1.
  • 3.3. Daily energy requirements varied between 13 and 66 cal g organic matter−1 d−1.
  • 4.4. Energy costs for maintenance were somewhat lower than in other reef-dwelling Anthozoa.
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13.
  • 1.1. Relative to rabbit erythrocytes, chicken red blood cells exhibit a much greater capacity to utilize [3H]adenine for nucleotide synthesis in vitro, even at 5°C and in the absence of added inorganic phosphate.
  • 2.2. This difference is largely due to a higher concentration of phosphoribosylpyrophosphate and greater activity of adenine phosphoribosyltransferase in the avian cells. lli]3. The capacity of avian erythrocytes for utilization of guanine and hypoxanthine is several fold less than that of adenine.
  • 3.4. The data are consistent with lower activity for hypoxanthine/guanine phosphoribosyltransferase than for adenine phosphoribosyltransferase in intact chicken erythrocytes.
  • 4.5. The results indicate that reutilization of adenine by chicken erythrocytes may be physiologically significant.
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14.
  • 1.1. Rates of water loss in Megetra cancellata were very high compared to those reported for other xeric arthropods.
  • 2.2. Hemolymph weight in hydrated animals was 43.0% of the total body weight while it was 24.7% in desiccated animals that had lost 16.1% of their body weight as water.
  • 3.3. Hemolymph osmotic potential increased from 417 to 447 mOsm/kg in desiccated beetles, but osmotic regulation was evident.
  • 4.4. Total hemolymph protein mass and concentration decreased in desiccated beetles while amino acid concentrations remained constant (at about 70 mM).
  • 5.5. Na+ and −PO4 concentrations increased in desiccated beetles.
  • 6.6. Cl and K+ concentrations in desiccated beetles were equal to those in undesiccated beetles.
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15.
  • 1.1. Food consumption, assimilation and passage rates of an elephant shrew, Elephantulus edwardii, on three natural diets (cockroaches, locusts and termites) and one artificial cereal diet (Pronutro) were compared.
  • 2.2. Daily food consumption varies significantly between the diets and was partly related to % assimilation, which was highest on Pronutro and cockroaches (71%) and lowest on termites (31%).
  • 3.3. Throughput times were estimated using soluble (51 Cr-EDTA) and particulate markers in the Pronutro diet. First appearance of the soluble marker (0.5 hr) was significantly earlier than for the particulate marker (1.85 hr); 50% appeared at 3.2 and 3.35 hr for the soluble and particulate markers, respectively.
  • 4.4. The distribution of particulate markers in the digestive tract showed some retention in the stomach, ileum and colon, but rapid movement through the duodenum and very little entry to the caecum.
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16.
  • 1.1. Ration and body size effects on specific dynamic action (SDA) were investigated in the supralittoral isopod Ligia pallasii using seaweed and chemical diets.
  • 2.2. SDA increased asymptotically with ingested meal size for all diets.
  • 3.3. Body weight had a significant positive effect on SDA for only one of the six diets tested, but weak tendencies were present in the data for the other diets.
  • 4.4. SDA appeared to increase geometrically with increasing concentration of amino acids at high ration levels.
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17.
  • 1.1. Fingerlings of intergenious hybrid Russian sturgeon (Acipenser guldenstadti) × beluga (Huso huso) weighing 22 g reared in water with salinity 18 ppt were fed nine diets differing in protein and fat content.
  • 2.2. The increase of dietary protein content (from 45 to 52%) improved the fingerlings growth rate, food and protein conversion efficiencies. No effect of further protein content increase to 60% was observed.
  • 3.3. The increase of dietary fat content from 10 to 20% positively influenced all growth results.
  • 4.4. The muscular lipid content increased following the increase in dietary fat due to accumulation of triacylglycerols.
  • 5.5. Distinctive leucopenia in neutrophils and leucophilia in lymphocytes following dietary protein and fat content increase were observed.
  • 6.6. It was concluded that within the analysed range of values the increase of dietary protein and lipid content improved the physiological status of sturgeon hybrid fingerlings.
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18.
  • 1.1. The amount of sugar required for growth of Heliothis zea larvae on a chemically defined diet was determined.
  • 2.2. Larvae grew well on fructose, galactose, sucrose, trehalose and raffinose diets but not on diets containing more than 0.5% glucose.
  • 3.3. A starch diet did not promote rapid larval growth.
  • 4.4. Hemolymph trehalose levels in 12-day-old larvae ranged from none to 45μmoles/ml.
  • 5.5. A method for analysis of hemolymph trehalose by gas chromatography is described.
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19.
  • 1.1. Subcellular distribution of (NA+, K+-ATPase and ouabain-insensitive ATPase (Mg2+-ATPase) are compared in branchial tissues of the euryhaline crab, Eriocheir sinensis, acclimated to fresh water.
  • 2.2. Both the anterior and posterior gills contain cAMP-dependent protein kinase and endogenous protein substrate for phosphorylation.
  • 3.3. Phosphorylation occurs in both “particulate” and “soluble” subcellular fractions but its stimulation by cAMP is restricted to the “soluble” fraction.
  • 4.4. serotonin (5-HT) and dopamine receptors are present only in the “light particulate” fraction isolated from the posterior gills.
  • 1.(a) Serotonin and dopamine have no effect on the phosphorylation observed in a subcellular fraction alone.
  • 2.(b) Activation of the phosphorylation by serotonin and dopamine is found when the soluble fraction (source of cAMP-dependent protein kinase) is added to the fraction P3 from the posterior gills.
  • 3.(c) No activation occurs with the fractions P3 as well as P1 or P2 (not shown) from anterior gills of fresh water crab.
  • 4.(d) Cyproheptadine, a serotonin receptor antagonist, inhibits the 5-HT dependent increase in phosphorylation.
  • 5.(e) The dopamine receptor antagonist, chlorpromazine, inhibits dopamine-stimulated phosphorylation.
  • 6.5. Ouabain mimics the effect of cyproheptadine on the serotonin-stimulated phosphorylation found in the posterior gills.
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20.
  • 1.1. The metabolism of purine bases and nucleosides in cotyledons and embryonic axes of black gram (Phaseolus mungo L.) was studied.
  • 2.2. A large portion of absorbed [8-14C]adenine, [8-14C]guanine and [8-14C]adenosine was salvaged in nucleotide and nucleic acid synthesis.
  • 3.3. Most of the radioactivity of [8-14C]hypoxanthine and [8-14C]inosine was incorporated into allantoin and allantoic acid.
  • 4.4. Activity of adenine phosphoribosyltransferase in enzyme extracts was much higher than that of hypoxanthme and guanine phosphoribosyltransferase(s).
  • 5.5. Apparent activity of adenosine kinase was higher than that of inosine kinase. 6. NAD+-dependent xan thine dehydrogenase was detected in both cotyledons and embryonic axes of the seedlings.
  • 6.7. The capacity of purine salvage was higher m 24 hr old cotyledons than 24 and 48 hr old embryonic axes. The reverse was observed concerning that of purine degradation.
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