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1.
  • 1.1. Two columnar cacti in the Sonoran Desert, agria and organpipe, contain medium chain (C8−C12) fatty acids.
  • 2.2. Necrotic tissues of these cacti serve as feeding and breeding substrates for Drosophila mojavensis but not D. nigrospiracula.
  • 3.3. Results show that capric and lauric acids are the predominant fatty acids of both cacti.
  • 4.4. Fatty acid chain length exhibits a differential effect on larval viability with caprylic acid (Q) having the greatest and myristic acid (C14) having the least effect.
  • 5.5. Drosophila mojavensis is more tolerant of free fatty acids than D. nigrospiracula, and this partly explains the ability of D. mojavensis to utilize agria and organpipe cacti.
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2.
  • 1.1. The effect of myo-inositol on the ability of three species of nematodes to survive desiccation has been studied.
  • 2.2. Survival rates obtained from worms treated with an inositol bathing medium were compared with survival rates of worms treated with distilled or tapwater media.
  • 3.3. Highest survival rates were found in those nematodes that were placed in an inositol solution prior to desiccation.
  • 4.4. Tapwater facilitated higher revival rates than did distilled water in both D. dipsaci and D. myceliophagous.
  • 5.5. No such differences were found for A. tritici.
  • 6.6. The results are discussed in relation to the possible mechanisms of protection afforded by the different bathing media.
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3.
  • 1.1. Patterns of histone variants from three diptera, Ceratitis capitata, Dacus oleae and Drosophila melanogaster were compared to mouse and to Plodia interpunctella variant patterns.
  • 2.2. The three diptera contain histones which comigrate on two dimensional gels with H3.2, H3.3 and H4 in mouse and Plodia. H2A.1 and H2B.1 comigrate with Plodia H2A.1 and H2B.1 and are different from mouse, whilst H2A.Z has a different mobility to that of Plodia and mouse.
  • 3.3. The iodinated peptides obtained from H2A.1 and H2A.2 of the diptera studied are compared to mouse and Plodia H2A.1 and H2A.Z peptides.
  • 4.4. The histone variants from three developmental stages, larval, pupal and adult of the three diptera were identified and compared.
  • 5.5. The same histone variant pattern is found through all stages of development.
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4.
  • 1.1. Chemical structures were determined for the cuticular alkanes, alkenes, and certain of the alkadienes for 11 D. virilis group species.
  • 2.2. Male-specific hydrocarbons occurred in five species: these were 9-heneicosene in D. americana and D. novamexicana, 10-heneicosene in D. virilis, 5,13- and 5,15-pentacosadienes in D. kanekoi, and 9-pentacosene in one strain of D. lummei.
  • 3.3. Hydrocarbon profiles of newly emerged flies always differed from mature files.
  • 4.4. Relationships among the species, with respect to hydrocarbon profiles, were investigated by cluster analysis.
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5.
  • 1.1.|The infective larvae of Ascaris suum develop in the egg between the temperatures 16 ± 1°C and 34 ± 1°C. Within this temperature range, increases in temperature increase the rate of development. The maximum rate of egg development is attained at 31 ± 1°C.
  • 2.2.|Eggs embryonated at 28 ± 1°C and above give rise to infective larvae which have less ability to hatch in vitro, shorter longevity when aged in phosphate buffered saline (pH 7.2) at 37°C, and more limited ability to penetrate tissue membranes in vitro, when compared with those larvae from eggs embryonated at lower temperatures.
  • 3.3.|Maximum larval viability and ability to penetrate tissues in vitro was achieved when eggs were embryonated at 22 ± 1°C. These results suggest that the optimal temperature for rate of development and larval viability, or survivability are not the same, a point which has not previously been emphasised.
  • 4.4.|The practical significance of these results are discussed in relation to the epidemiology of Ascarias and the known biology of the parasite.
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6.
  • 1.1. A variety of haematological parameters were determined in adult Dasyurus viverrinus.
  • 2.2. Haemoglobin and red cell counts were high with a very low mean cell volume.
  • 3.3. Basophils are absent but the eosinophils contain small numbers of basophilic granules which may indicate a dual role for this cell.
  • 4.4. “Ring Form” leucocytes are present.
  • 5.5. Three types of red cell picture could be identified, some animals showing large numbers of spherocytes, spicule cells, and inclusion bodies.
  • 6.6. These cells resemble those found in some inherited human haemolytic anaemias but there was no evidence of haemolysis in the animals.
  • 7.7. An alkali resistant haemoglobin component is present.
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7.
  • 1.1. The activity of l-gulonolactone oxidase (EC 1.1.3.8) in livers of 49 species of eutherian mammals varied intraspecifically among individuals; coefficients of variation were 0.2 to 0.4 in many species.
  • 2.2. Differences observed in l-gulonolactone oxidase activity among strains of laboratory rats and domestic rabbits are probably genetically controlled.
  • 3.3. Pronounced sex differences in l-gulonolactone oxidase activity were found in some species, particularly in the genera Peromyscus, Reithrodontomys and Onychomys.
  • 4.4. Mormota monax exhibited seasonal variation in l-gulonolactone oxidase somewhat like that previously observed in Sylvilagus floridanus; no such seasonal variation was found in Sciurus carolinensis.
  • 5.5. Hibernation did not affect l-gulonolactone oxidase activity in Spermophilus tridecemlineatus.
  • 6.6. In four species of rodents, Microtus ochrogaster, Tylomys panamensis, Octodon degus and Sigmodon hispidus, l-gulonolactone oxidase activity was not affected by the level of dietary ascorbate.
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8.
  • 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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9.
  • 1.1. Brain trehalase specific activity and trehalosemia were measured during the end of the developmental life cycle in non-diapausing and diapausing insects.
  • 2.2. During non-diapausing development, trehalosemia reached maximum values at the beginning of pupal life. Then a constant decrease was observed up to the end of adult life.
  • 3.3. The specific activity of brain trehalase was maximum when the insects were in active feeding periods, minimum activity appearing during moulting phases.
  • 4.4. During diapausing development, trehalosemia was very high at the beginning of pupal life, particularly when insects were exposed to wintering conditions.
  • 5.5. When diapause was broken, trehalosemia fell, announcing adult emergence.
  • 6.6. Brain trehalase activity showed the same qualitative variations as in non-diapausing larvae, but with rather lower values.
  • 7.7. During pupal life, brain trehalase activity decreased markedly during the long period necessary to obtain diapause breakdown.
  • 8.8. Wintering conditions allow a progressive increase of brain trehalase activity, which preceded the fall of trehalosemia.
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10.
  • 1.1. An alkaline p-nitrophenylphosphate phosphatase has been purified 440-fold from extracts of Hatobacterium halobium.
  • 2.2. The enzyme has an apparent molecular weight of 24,000.
  • 3.3. A Km value for p-nitrophenylphosphate of 1.12mM has been found under optimal conditions.
  • 4.4. The enzyme is selectively activated and stabilized by Mn2+.
  • 5.5. It requires high salt concentrations for stability and maximum activity.
  • 6.6. It displays an unusual restricted substrate specificity of 25 phosphate esters tested, only phosphotyrosine and casein were hydrolysed besides p-nitrophenylphosphate.
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11.
  • 1.1. Levels of progesterone, pregnenolone, testosterone, 5α-dihydrotestosterone, estrone and estradiol were measured by radioimmunoassay in purified gonadal extracts of larval and adult male and female Locusta migratoria.
  • 2.2. The average steroid contents varied between less than 1 ng to more than 160 ng/g tissue.
  • 3.3. Young adults were treated with precocene or ketoconazole in an attempt to influence the steroid contents in gonads.
  • 4.4. Ketoconazole treatment had no effect on the steroid contents in gonads whereas precocene treatment resulted in higher contents of androgens.
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12.
  • 1.1. Per cent total body water content (%TBW), cuticular permeability (CP), rate of water loss, critical thermal maxima (CTMax), and upper lethal limits (ULL) were determined for Pacific beetle, Diploptera punctata (Eschscholtz), Surinam, Pycnoscelus surinamensis (L.), and Turkestan, Blaita lateralis (Walker), cockroaches.
  • 2.2. Initial body mass ranged from 153.16 to 464.96 mg, for D. punctata and P. surinamensis cockroaches, respectively. Mean %TBW was 57.8 for P. surinamensis and 67.7 for B. lateralis.
  • 3.3. Mean cuticular permeability was not related to initial mass and ranged from 20.9 to 38.7 μg/cm2/hr/mmHg for D. punctata and P. surinamensis, respectively.
  • 4.4. Cumulative mass loss and %TBW lost increased linearly with desiccation time.
  • 5.5. CTMax ranged from 43.2°C for D. punctata to 44.3°C for P. surinamensis. There were significant, but small differences in CTMax among the three species.
  • 6.6. ULL were 2.2 to approximately 4°C greater than CTMax. The greatest ULL was 48.1°C for B. lateralis and the lowest ULL was 45.0°C for D. punctata.
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13.
  • 1.1. A choriolytic enzyme was isolated from the hatching medium of the pike, Esox lucius.
  • 2.2. The enzyme is defined as hatching enzyme.
  • 3.3. The molecular weight of the enzyme is 24,000.
  • 4.4. The enzyme is a glycoprotein containing 2% carbohydrate.
  • 5.5. Its isoelectric point is 6.5.
  • 6.6. The pH optimum is around pH 8.
  • 7.7. The enzyme molecule contains two disulfide bonds but no free cysteine.
  • 8.8. Inhibitor studies and metal analysis show that the enzyme is a zinc-metalloprotease.
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14.
  • 1.1. Hemolymph osmoregulation was examined in Chrysochus auratus, Tetraopes tetrophthalmus and Tenebrio molitor. These beetles differed in their water loss rates and in the availability of free water in their habitats.
  • 2.2. During dehydration at comparable rates, osmotic responses were similar in these species. Osmoregulation after rehydration was better in C. auratus.
  • 3.3. Osmoregulation ability was not significantly affected by the beetle's rate of dehydration.
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15.
  • 1.1. Arginase, ornithine decarboxylase and S-adenosylmethionine decarboxylase are active in both retina and brain. Activity is higher in cerebellum than in the cerebral hemispheres and optical lobes.
  • 2.2. Arginase and ornithine decarboxylase are very active in the retina of very young chicks, while S-adenosylmethionine decarboxylase is poorly active. By contrast, S-adenosylmethionine decarboxylase is much more active in brain.
  • 3.3. The pattern of activity during development is different; only ornithine decarboxylase is very active during embryonal life; S-adenosylmethionine decarboxylase, at all events in brain, is more active in adult life.
  • 4.4. Ornithine decarboxylase is inhibited in vitro by α-difluoromethylornithine, but not in vivo. Diaminopropane inhibits brain ornithine decarboxylase, but does not induce an ornithine decarboxylase-antizyme.
  • 5.5. Methylglyoxal bis(guanylhydrazone) promotes an increase of S-adenosylmethionine decarboxylase activity in both the brain and the retina in vivo.
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16.
  • 1.1. The cardiovascular physiology of adult Carcinus maenas (L.) emerging into air has been investigated at three different air temperatures.
  • 2.2. Transition from seawater to air or vice versa triggered transient increases in cardiac and locomotor activity.
  • 3.3. However, crabs became inactive 5–10 min after emerging from seawater (15°C) into air at the same temperature (15°C) or at lower temperatures (12–13°C) and heart rate fell.
  • 4.4. At higher air temperatures (18–20°C) heart rate rose but to a lesser extent than predicted from aquatic Q10 heart-rate values.
  • 5.5. Crabs were again quiescent in aerial conditions.
  • 6.6. Mean arterial oxygen tension (Pao2) was ~ 74 mmHg in submerged crabs but fell to ~ 38 mmHg in air while mean arterial carbon dioxide tension (Pao2) increased from 1 to 4 mmHg resulting in respiratory acidosis.
  • 7.7. A model of gill function is proposed to explain the development of internal hypoxia in air.
  • 8.8. The results are discussed in relation to the distribution of adult and juvenile C. maenas in situ.
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17.
  • 1.1. Procarboxypeptidase (W-PCPA) was purified from the pancreas of the sei whale Balaenoptera bolealis.
  • 2.2. W-PCPA was obtained as a homogeneous protein in polyacylamide gel disc electrophoresis.
  • 3.3. W-PCPA has a molecular weight of 75,000.
  • 4.4. Amino acid composition of W-PCPA was compared with that of bovine procarboxypeptidase as A S5 (PCPA-S5).
  • 5.5. W-PCPA may be two subunits, and the aggregate form may resemble PCPA-S5.
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18.
  • 1.1. Components of the cell surface of Crithidia guilhermei, Crithidia deanei and Crithidia oncopelti were radioiodinated by the iodogen technique. The distribution of proteins in the detergent-poor (DPP) and detergent-enriched phase (DRP) were studied using a phase separation technique in Triton X-114 and one- and two-dimensional polyacrylamide gel electrophoresis in sodium dodecyl sulphate (1D and 2D SDS-PAGE).
  • 2.2. Significant differences were noted in the proteins present in the DRP when the three species were compared.
  • 3.3. Two major bands with mol. wt 28,000 and 56,000 and motility in the pH gradient of 7.4 and 6.3, respectively, were observed in C. guilhermei, but not discernible in C. deanei and C. oncopelti.
  • 4.4. One polypeptide with mol. wt 50,000 and p1 4.9 was identified in the DRP of C. deanei.
  • 5.5. A broad band with mol. wt 68,000–140,000 and pI 4.7–5.5 was clearly observed in the DRP of C. deanei and one or two polypeptides only present in the DPP were observed in the three Crithidia species analyzed.
  • 6.6. Our observations show that C. guilhermei has characteristic surface polypeptides not found in C. deanei and C. oncopelti.
  • 7.7. Our results, in association with those reported by others, show that the phase separation using Triton X-114 offers a simple approach to the separation and further analysis of a select group of proteins from the bulk of the cellular proteins.
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19.
  • 1.1. The biological properties of venoms from juvenile and adult common tiger snakes (Notechis scutatus) were compared.
  • 2.2. The lethality, procoagulant activity and enzymatic activities of the juvenile venom were not substantially different from those of the adult venom.
  • 3.3. Electrophoretic studies, however, indicated some minor differences in the protein composition of the juvenile and adult venoms.
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20.
  • 1.1. One adult male, eight pups (including two full term foetuses) and nine adult female harbour seals (Phoca vitulina) were analysed for indices of mixed function oxidase (MFO) activity.
  • 2.2. MFO activity was present in liver samples, but was at or below detection limits in samples of kidney, lung and pancreas.
  • 3.3. Hepatic ethoxyresorufin O-de-ethylase and benzo[a]pyrene hydroxylase activities were similar to those reported in other seals and in other mammals.
  • 4.4. Cytochromes P-450 and b5 concentrations were slightly lower than those observed in other mammals.
  • 5.5. MFO activities in newborn pups and foetuses were significantly lower than those in adult females.
  • 6.6. No qualitative differences in cytochrome P-450 isozyme distribution between foetal and adult samples could be discerned by electrophoresis.
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