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1.
  • 1.1. Serum from the Pacific hagfish,Eptatretus stouti,contains a complement-like protein (CLP).
  • 2.2. CLP from unfractionated hagfish serum and from affinity-purified preparations binds to yeast cell surfaces.
  • 3.3. Incubation with CLP enhances the phagocytosis of yeast by hagfish leukocytes.
  • 4.4. CLP-mediated opsonization can be inhibited by anti-CLP antibody, EDTA, d(+)mannose and l(+)rhamnose.
  • 5.5. Additional opsomic factors are also in hagfish serum.
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2.
  • 1.1. Role of NADP-glutamate dehydrogenase in the depletion of citrate was analyzed using permeabilized yeast cells.
  • 2.2. Citrate was converted to 2-oxoglutarate, which was then metabolized to glutamate by NADP-glutamate dehydrogenase in the presence of ammonium ion.
  • 3.3. Formation of 2-oxoglutarate plus glutamate was in good agreement with the concentration of citrate decreased. Glutamate formation can be a good indicator of the depletion of citrate, because 70% of the citrate decreased was converted to glutamate.
  • 4.4. Glycolytic activity was closely correlated with the decrease in citrate under the in situ conditions.
  • 5.5. NADP-glutamate dehydrogenase increased in anaerobically grown yeast cells.
  • 6.6. An effective depletion of citrate by increased synthesis of NADP-glutamate dehydrogenase can explain the lowered mechanism of citrate causing glycolytic stimulation under the anaerobic growth conditions of yeast.
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3.
  • 1.1. The effect of regular handling on fear reactions was investigated in mallard (Anas platyrhynchos) by exposing six hand-reared and four wild ducks to an approaching human being and recording heart rates with an external ECG device.
  • 2.2. All ducks reacted to the approach with tachycardia, but the response was significantly less in tame birds.
  • 3.3. Hand-reared females showed less response than males. No sex-linked differences were apparent in the wild ducks.
  • 4.4. Decreasing responses throughout the experiments were only found in tame birds.
  • 5.5. Fear or stress reactions can apparently be diminished through habituation induced by regular handling.
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4.
  • 1.1. Growth rates and body condition factors for native wild and captive-raised juvenile alligators (Alligator mississippiensis) that had been released to the wild were studied using tag-recapture methods for 274 alligators over a 4-year period. Alligators were grouped by sex, size class, source (farm-released vs native wild) and as to whether they had overwintered or not.
  • 2.2. In most groups, the farm-released alligators grew significantly better than wild alligators matched for sex and size; in the remaining groups the post-release alligators grew as well as their counterparts, though not better.
  • 3.3. Overwintering tended to slow growth rates in both groups, but farm-released alligators still demonstrated superior growth over native wild alligators even after overwintering.
  • 4.4. Males tended to grow faster than females, though this trend was not always significantly greater. In no matched group did females grow faster than males.
  • 5.5. Growth rates diminished with increasing size in native wild alligators (smaller alligators grew faster), but growth rates of farm-released alligators remained accelerated even at the larger size classes.
  • 6.6. Growth curves were constructed using known recapture data with three growth models (von Bertlanffy, Gompertz and logistic); the calculated maximum attainable length and growth parameters were significantly larger (P < 0.01) for farm-released alligators than wild using all three models.
  • 7.7. Body condition factors were not different in captive-raised post-released alligators than native wild alligators.
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5.
  • 1.1. Eggs of wild cod, and of farmed cod fed (a) a diet supplemented with astaxanthin and (b) a diet supplemented with both astaxanthin and canthaxanthin, were analysed with respect to carotenoids.
  • 2.2. The total carotenoid contents in eggs were 0.7 ppm for wild cod and 0.5 ppm for farmed cod.
  • 3.3. Cod, having white flesh, deposit ketocarotenoids in the eggs, preferably astaxanthin.
  • 4.4. Canthaxanthin can replace astaxanthin in the eggs, but astaxanthin appears to be deposited preferentially when both carotenoids are present in the diet.
  • 5.5. The isomer distribution of (3S, 3′S):(3R, 3′S, meso):(3R, 3′R) astaxanthin in the eggs reflected the isomer composition of the diet.
  • 6.6. Echinenone, 4′-hydroxyechinenone, adonixanthin and zeaxanthin encountered in cod eggs may represent reductive metabolites of canthaxanthin and astaxanthin.
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6.
  • 1.1. This work represents the first approach to characterize the transport system of haem pathway precursors, such as δ-aminolevulinic acid (ALA), in two strains of Saccharomyces cerevisiae, a wild type, D27, and a HEM R+ mutant.
  • 2.2. ALA transport occurs unidirectionally by a sole active system with an apparent KM of 0.10 mM, at the optimum pH of 5.0. ALA uptake is influenced by both the carbon and nitrogen source; this suggests a rather complex regulation mechanism.
  • 3.3. This transport is not mediated by the general amino acid permease (GAP).
  • 4.4. ALA uptake is strongly inhibited by compounds harboring a methyl-amine terminus suggesting that this group is essential for ALA transport; however, the electric environment of the carboxylic group may be also important for the interaction between ALA and its transporter active site.
  • 5.5. We have found differences in ALA transport which would indicate a different regulation mechanism for this system in both strain cells.
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7.
  • 1.1. In the present study the major metabolic pathways of glucose metabolism were determined in isolated liver cells using [2-13C]acetate and 13C magnetic resonance spectroscopy.
  • 2.2. The relative reaction rates of glucose synthesis to the TCA cycle were determined from the 13C distribution in glucose where the overall 13C enrichment of glucose was 6.41 ± 1.94% (mean ± SD; n = 6) and the mean 13C enrichment of C1, C2, C5, C6 to C3, C4 was 2.63 ± 0.30.
  • 3.3. Since the distribution of tracer in glucose is a function of the relative entry rates of pyruvate to acetyl-CoA into the oxaloacetate pool this was calculated to be 0.32 ± 0.15 and the factor for carbon exchange (1/P) between the gluconeogenic pathway and the TCA cycle was calculated to be 1.03 ± 0.20.
  • 4.4. With this carbon exchange factor and the approximated 13C enrichment of acetyl-CoA the intramitochondrial 13C enrichment of phosphoenolpyruvate was calculated and the “true” rate of hepatic gluconeogenesis from phosphoenolpyruvate estimated.
  • 5.5. Since acetate was metabolized solely in liver cells the 13C enrichment of acetyl-CoA could be approximated from that of 3-hydroxybutyrate.
  • 6.6. The carbon 13 enrichment of 3-hydroxybutyrate and phosphoenolpyruvate was 5.89 ± 0.90% and 5.96 ± 1.67%, respectively.
  • 7.7. The per cent gluconeogenesis from phosphoenolpyruvate calculated as the ratio of the 13C enrichment of glucose to that of 3-hydroxybutyrate times 1/P was 107 ± 8%.
  • 8.8. In this study the validity of assessing isotopic exchange at oxaloacetate as suggested by Katz [Katz J. (1985) Am. J. Physiol.248, R391–R399] when interpretation of the data are not obscured by pseudoketogenesis.
  • 9.9. Magnetic resonance spectroscopy provides direct information about intramolecular tracer distribution by which flux rates in major metabolic pathways are derived.
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8.
  • 1.1. A lipoxygenase preparation was obtained from Thermoactinomyces vulgaris and was purified by affinity chromatography on a linoleyl aminoethyl sepharose column.
  • 2.2. Two active fractions were obtained.
  • 3.3. The fraction obtained by elution with 100 mM borate buffer pH 9.0 was used in the subsequent work.
  • 4.4. Th. vulgaris lipoxygenase oxidized linoleic acid into two products: 13-HPOD and 9-HPOD at a ratio of 44 to 56, respectively.
  • 5.5. The identification and characterization of the isomers was done by HPLC, I.R. and mass spectrometry.
  • 6.6. When arachidonic acid was used as substrate, 15-HPETE and 15-HETE were found to be the main enzymatic products.
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9.
  • 1.1. The histopathology of zebra mussel populations (Dreissena polymorpha) which were transplanted and exposed in baskets in the Dutch sector of the River Maas (5 locations) were compared with indigenous wild mussels at the same locations and at a clean reference site in the Ijsselmeer.
  • 2.2. All groups were sectioned histologically and examined to quantify cytological damage and pathology of a wide range of tissues, as well as to examine parasitology and to assess their reproductive state.
  • 3.3. Results show a significant reduction in general cytological quality and an increase in observed pathological conditions in the wild populations at the 3 downstream stations.
  • 4.4. The transplanted (active biomonitoring) groups of mussels clearly showed a similar trend in condition after only 42 days exposure at these sites.
  • 5.5. The influence of an industrial spillage of Cd in the Maas during the exposures is examined against this background of locally varying “health”.
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10.
  • 1.1. The results of chemically crosslinking yeast cytochrome c peroxidase with both horse and yeast iso-1 ferricytochromes c have been studied by a combination of gel electrophoresis and proton NMR spectroscopy.
  • 2.2. The complexes were formed at a variety of potassium phosphate concentrations ranging from 10 to 300 mM using the water soluble crosslinking agent, EDC (l-ethyl-3-[3-(dimethylamino)propyl]-carbodiimide).
  • 3.3. The primary crosslinking product in both cases is the 1:1 covalent complex, but, for each pair of partner proteins the yield of the 1:1 crosslinked complex varies with the salt concentration.
  • 4.4. Furthermore, at low salt concentrations the yield of the 1:1 covalent complex involving horse cytochrome c is much larger than the yield of the 1:1 covalent complex formed with yeast iso-1 cytochrome c, whereas at high salt concentrations the situation is reversed.
  • 5.5. Proton NMR spectroscopy, in combination with gel electrophoresis, provides evidence for the formation of different types of 1:1 complexes for the peroxidase/yeast cytochrome c pair and has been used to study the effect of changes in the solution ionic strength upon both the peroxidases/horse cytochrome c and the peroxidase/yeast cytochrome c complexes.
  • 6.6. This work indicates that electrostatic interactions between proteins play a dominant role in formation of complexes between cytochrome c peroxidase and horse ferricytochrome c, whereas the hydrophobic effect plays a comparatively larger role in stabilizing complexes between cytochrome c peroxidase and yeast iso-1 ferricytochrome c.
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11.
  • 1.1. The influence of temperature (14,19, 24°C), salinity (26,32, 38,44%.) and food type (artificial diets: Fryfood, Mytilus, Soya, Yeast, Spirulina) on the respiratory rate of Tisbe holothuriae has been studied.
  • 2.2. Oxygen consumption decreased with decreasing temperature, but with a greater rate at supra- or subnormal salinities.
  • 3.3. Multiple-regression analysis showed the quadratic effect of temperature and the linear effect of salinity to be the more important factors affecting respiration.
  • 4.4. The food type also seems to exert an important effect on oxygen consumption.
  • 5.5. A significant lowering of respiration was observed for all food tested when the animals were starved.
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12.
  • 1.1. Malleefowl Leipoa ocellata have a lower than predicted metabolic rate, a finding common to many arid adapted avian species.
  • 2.2. Evaporative water loss was as expected by allometric analysis. However, in the wild this species probably reduces its evaporative water loss because their water turnover rate is extremely low.
  • 3.3. Malleefowl coped with temperatures up to 40°C well, but above this temperature they become highly agitated.
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13.
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Highlights
  • •Developed a data processing pipeline to format phosphopeptide identifications.
  • •Identified the preferred substrate motif for FLT3 and mutant kinases.
  • •Designed and validated a panel of pan-FTL3 artificial substrates.
  • •Monitored FLT3 and mutant kinase activity through FAStide phosphorylation.
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14.
  • 1.1. To characterize an enzyme which metabolizes retinal in liver microsomes, several properties of the enzymatic reaction from retinal to retinoic acid were investigated using rabbit liver microsomes.
  • 2.2. The maximum pH of the reaction in the liver microsomes was 7.6.
  • 3.3. The Km and Vmax values for all-trans, 9-cis and 13-cis-retinals were determined.
  • 4.4. The reaction proceeded in the presence of NADPH and molecular oxygen.
  • 5.5. The incorporation of one atom of molecular oxygen into retinal was confirmed by using oxygen-18, showing that the reaction comprised monooxygenation, not dehydrogenation.
  • 6.6. The monooxygenase activity was inhibited by carbon monoxide, phenylisocyanide and antiNADPH-cytochrome P-450 reductase IgG, but not by anti-cytochrome b5 IgG.
  • 7.7. The enzymatic activity inhibited by carbon monoxide was photoreversibly restored by light of a wavelength of around 450 nm.
  • 8.8. The retinal-induced spectra of liver microsomes with three isomeric retinals were type I spectra.
  • 9.9. The microsomal monooxygenase activity induced by phenobarbital or ethanol were more effective than that by 3-methylcholanthrene, clotrimazole or β-naphthoflavone.
  • 10.10. These results showed that the monooxygenase reaction from retinal to retinoic acid in liver microsomes is catalyzed by a cytochrome P-450-linked monooxygenase system.
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15.
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16.
This paper comments on: Low, B. S., Alexander, R. D., and Noonan, K.M. Human hips, breast, and buttocks: Is fat deceptive? Ethology and Sociobiology 8: 249-247, 1987. In it I argue that:
  • 1.1. Sexual selection has probably not been the most important selection pressure on
  • 2.female human body shape.
  • 3.2. Male humans in different cultures find different aspects of the female body attractive
  • 4.and therefore are unlikely to have exerted consistent directional sexual selection on
  • 5.the female body.
  • 6.3. Breast size is not correlated with lactation success.
  • 7.4. Visible hip width is not correlated with parturition success.
  • 8.5. Women would lower their fitness if they tried to deceive men about their internal
  • 9.pelvic dimensions.
  • 10.6. There are many alternative hypothesis to explain the existence of fat onwomen's
  • 11.breast, hips, and buttocks.
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17.
  • 1.1. The phosphorylation of Escherichia coli proteins was analyzed comparatively before and after induction of the SOS response in a temperature-sensitive mutant strain.
  • 2.2. The presence of phosphorylated proteins was evidenced by gel electrophoresis and autoradiography after labelling with radioactive orthophosphate in vivo or radioactive adenosine triphosphate in vitro.
  • 3.3. Significant changes in the intensity of protein labelling were observed upon induction of the SOS functions: six proteins were found to be more phosphorylated while two others were less phosphorylated. Moreover, five additional proteins appeared to become phosphorylated exclusively during the SOS response. The molecular mass and isoelectric point of these various proteins were determined.
  • 4.4. For most proteins, the changes in the pattern of protein phosphorylation were concomitant with variations in the amount of protein synthesized.
  • 5.5. The changes in the pattern of phosphoproteins observed during the SOS response were not due to the temperature shift required experimentally for expressing the SOS phenotype.
  • 6.6. Phosphorylation was found to be catalyzed by protein kinases that modify amino acid residues at hydroxyl groups in protein substrates.
  • 7.7. Both in vivo and in vitro studies brought evidence that neither RecA nor LexA, the two key regulatory proteins of the SOS functions, were capable of undergoing phosphorylation.
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18.
  • 1.1. The ciliary membrane lipid composition and electrophysiology of the behavioral mutant of Paramecium tetraurelia, barium A (d4–592), were previously shown to differ from those of wild-type 51S when both strains were grown in low sterol medium.
  • 2.2. In this study, the phospholipid fatty acid composition of the two strains was shown to differ regardless of the level of sterol supplementation or culture age (growth phase).
  • 3.3. The ratio of linoleic to γ-linolenic acid, 18:2(9,12)/18:3(6,9,12), was consistently higher in baA compared to wild-type phospholipids, largely because of a dramatic shift in the ratio of these two fatty acids esterified at the 2 position of 1-alkyl-2-acyl-sn-glycero-3-phosphorylcholine (GPC).
  • 4.4. These data support the hypothesis that a specific Δ6 fatty-acyl desaturase, which directly desaturates phospholipid and shows a preference for GPC as its substrate, is impaired as a result of the barium A mutation.
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19.
  • 1.1. Glucose pool size, space, entry rate, and turnover time were estimated from the specific radioactivity vs time curves of [3H] and [14C]glucose administered as a single injection in the euro (Macropus robustus erubescens) and the sympatric feral goat (Capra hircus).
  • 2.2. Digestible energy intake was greater (P < 0.05 ± SE) in the goat than in the euro (798 ± 64 vs 624 ± 31kJ/kg0.75 × day).
  • 3.3. However, there were no significant differences between the two species in parameters of glucose metabolism.
  • 4.4. The use of an implantable osmotic infusion pump to deliver isotopic glucose showed promise as a means of avoiding the stress involved with the single injection technique.
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20.
  • 1.1. Nematocyst structural proteins (NSP) from the sea anemones Aiptasia pallida and Metridium senile and the siphonophore Physalia physalis are primarily low molecular weight collagens linked by disulfide bonds.
  • 2.2. NSP patterns resolved by SDS-PAGE revealed a common, major collagen species (40 kDa) in each nematocyst type, together with other collagens and non-thiol-containing proteins.
  • 3.3. For each cnidarian, NSP glycosylation profiles were significantly different.
  • 4.4. Monoclonal antibodies against Aiptasia NSP demonstrated a differential distribution between capsule wall and thread.
  • 5.5. NSP differences would account for the diversity of morphologic and functional types.
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