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1.
  • 1.1. Gastrointestinal (GI) transit and emptying of male and female 15-day-old chickens treated with testosterone, estradiol and progesterone was measured by means of 14C-polyethylene glycol-4000.
  • 2.2. All the administered sex hormones increased GI motility at the shortest time (0.5 and 1 hr) after the marker administration, but decreased GI motility at the longest times (2 and 4 hr). This motor pattern agrees with the known anabolic role of sex hormones.
  • 3.3. We conclude that testosterone and estradiol increased GI motility and intestinal inhibitory reflexes. Thus, chicks' and mammals' GI motility were modified by testosterone and estradiol in a similar form.
  • 4.4. The effect of progesterone on the chick GI motility was contrary to that observed in mammals. This may happen because of increased inhibitory GI motor reflexes or direct inhibition of visceral smooth muscle activity.
  • 5.5. No statistical differences were observed between the sexes, which could be explained by the sexual immaturity of chicks.
  • 6.6. Chicks constitute good biological material to study the influence of sex hormones on avian GI motility.
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2.
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Highlights
  • •CMTM4 is associated with human spermatogenesis and sperm quality.
  • Cmtm4 knockout mouse were generated by CRISPR/Cas9 technology for male fertility research.
  • •CMTM4 is required for male fertility but not female fertility.
  • •Phenotype and quantitative proteomics of Cmtm4 KO mice reveal an association of CMTM4 with histone-to-protamine exchange, sperm motility and induction of the acrosome reaction.
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3.
  • 1.1. The mean annual Zn content of the sperm storage organs (uterus and epididymis) in Myotis velifer and M. lucifugus is two to three times higher than in corresponding tissues of other mammals.
  • 2.2. The content of Zn in the sperm storage organs and male accessory glands has an annual cyclic pattern. Significant increases are recorded at prehibernation insemination (September) and posthibernation conception (April/May).
  • 3.3. Zinc is present in the storage organs of bats throughout the spermatozoa storage phase of the reproductive cycle.
  • 4.4. Zinc, due to its regulatory effects on spermatozoa (maturation, metabolism, motility) may be important in sperm storage in hibernating bats.
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4.
  • 1.1. Nephron segments (rabbit) were dissected and explanted into primary culture.
  • 2.2. Outgrowth of epithelial cells and proliferation in monolayer from distal nephron segments was dependent upon cell substratum (plasma or collagen) and upon hormonal supplements of serum-free media.
  • 3.3. Distal nephron segments from cortex and outer medulla (thick ascending loop of Henle, collecting tubule) have differential requirements for growth-stimulation.
  • 4.4. Proximal epithelial tissue (embryonic Nephron Anlage) depends on serum or embryo extract for differentiation into convoluted segments.
  • 5.5. The mammalian nephron can be cultivated in vitro to form segmental epithelial monolayers.
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5.
  • 1.1. The sperm-agglutinating factor (SAF) could be induced in the serum of male Nile tilapias, Oreochromis niloticus, by injection of allogeneic sperm.
  • 2.2. Only one class of molecules was demonstrated to be SAF in the serum.
  • 3.3. Analysis on purified SAF revealed it to be a tetrameric molecule of IgM with a mol. wt of 760kD.
  • 4.4. Cross reaction of the IgM with sperm of other teleost species suggests that sperm-specific surface antigens may be in evolution.
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6.
  • 1.1. A method is described to measure cytosolic and mitochondrial metabolites in isolated kidney tubule suspensions.
  • 2.2. With the use of digitonin, 95% of cytosolic metabolites are released into the supernatant fraction whereas mitochondrial matrix enzymes are retained in the pellet fraction.
  • 3.3. In a study of adaptation to acidosis, different α-oxoglutarate gradients between the tubular cell compartments are obtained, when medium pH is changed from 7.0 to 7.8.
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7.
  • 1.1. African sharptooth catfish individuals, heterozygous for glucose phosphate isomerase (GPI-2), were selected as broodstock by using horizontal starch-gel electrophoresis.
  • 2.2. Ova of one heterozygous female were inseminated with cryopreserved and fresh milt from a corresponding male.
  • 3.3. Significant deviations from expected Hardy-Weinberg proportions occured for offspring obtained by using cryopreserved milt.
  • 4.4. Differences in genotypic variation seems to relate to different cryodiluents and the fertility thereof.
  • 5.5. Selection of breeding stock for aquacultural practices based on the above information is discussed.
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8.
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Highlights
  • •Proteome of mature boar spermatozoa from cauda epididymal and ejaculated sources were analyzed by iTRAQ-based LC-MS/MS.
  • •1,723 sperm proteins identified (974 of Sus scrofa taxonomy).
  • •1,602 sperm proteins quantified (960 of Sus scrofa taxonomy).
  • •32 Sus scrofa sperm proteins were differentially expressed among sperm sources.
  • •The proteome of boar spermatozoa is remodelled during ejaculation.
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9.
  • 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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10.
 
  • 1.The levels of water, Na, K, Ca and Mg in blood serum, brain and kidney and aldosterone level in blood of Naja haje haje were studied during the different phases of the annual cycle.
  • 2.The water content in the tissues studied displayed only minor changes as the animals passed from one phase to the other.
  • 3.A significant increase in Na was recorded in the brain during the different phases indicating a depressed sodium pump, whereas the blood Na level showed a significant decrease during hibernation.
  • 4.K increased in blood serum, brain and kidney during hibernation, while a nonsignificant decrease was found in blood serum during arousal. The brain may act as a potassium reservoir.
  • 5.An increase in Ca and Mg concentration was recorded in blood serum, brain and kidney during prehibernation and hibernation. The data suggested a homeostatic function in the transport and metabolism of these cations.
  • 6.Aldosterone exhibited a highly significant decrease especially during hibernation. The aldosterone regulation of ionic composition is discussed.
  • 7.Na/K and Ca/Mg ratios in the brain may explain the decreased excitability during winter torpor.
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11.
  • 1.1. To assess whether the stretch-activated (SA) channels in snail cells could contribute to osmoregulation, information is needed about the behaviour of the cells under anisosmotic conditions.
  • 2.2. Cells of Lymnaea stagnalis were therefore examined during acute hyposmotic stress (HOS).
  • 3.3. Kidney, heart and neuronal cells (monitored photographically) swelled less than expected for strictly semipermeable cells, but exhibited no regulatory volume decrease.
  • 4.4. Long-term viability of the cells was not compromised following acute hyposmotic stress.
  • 5.5. Quinidine, which blocks SA channels in Lymnaea, intensified stress-induced swelling most markedly in kidney cells.
  • 6.6. The data can, however, be explained without invoking recruitment of SA channels.
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12.
  • 1.1. Seasonal variation in total lipids was examined in several body components of the turtle Sternotherus odoratus.
  • 2.2. Carcass fat stores in both sexes were depleted during winter. Additionally, a decline in carcass lipids was associated with increases in gonadal mass.
  • 3.3. Concentrations of liver lipids were maximal during August and minimal during winter.
  • 4.4. Males showed little seasonal change in plasma lipid levels, whereas females had seasonal peaks temporally associated with ovarian development and carcass fat storage.
  • 5.5. Ovarian concentrations of lipids were minimal after nesting and increased during fall.
  • 6.6. Results suggest that S. odoratus uses stored fats both for reproduction and maintenance during winter.
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13.
  • 1.1. The subcellular distribution of nine transition metals (plus four additional elements) was measured in the kidney tissue of the quahog, Mercenaria mercenaria.
  • 2.2. Elemental analyses of the subcellular fractions indicated three main patterns of metal distribution within kidney cells.
  • 3.3. Barium, iron, manganese and lead were associated primarily with kidney granules.
  • 4.4. Cadmium, copper, potassium and magnesium were found mainly in the cytosolic fraction.
  • 5.5. Calcium, phosphorus and zinc were found in all isolated fractions, probably reflecting the important roles that these elements play in bivalve metabolism.
  • 6.6. The organelle composition of the isolated subcellular fractions was determined using marker enzyme assays and microscopic techniques.
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14.
  • 1.1. The in trarumen pressure (IRP) of eight calves was elevated for 10 min by nitrogen insufflation to pressures of 5, 10, 15 and 20 cm H2O.
  • 2.2. Rumen motility was evaluated by recording reticulorumen myoelectrical activity and changes in luminal pressure, while eructation was determined from anterior tracheal and face mask gas expulsion.
  • 3.3. The elevation of IRP increased primary rumen contraction frequency slightly and secondary rumen contraction frequency as much as 3-fold.
  • 4.4. Rumen gas was expelled only during rumen contractions and virtually always during secondary rumen contractions.
  • 5.5. Cattle do not exhibit the primary-secondary contraction previously identified in sheep and their rumen motility appears to be less sensitive than sheep to increases in IRP.
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15.
  • 1.1. Heart rates of adult aquatic red-spotted newts can be conveniently recorded using an impedance pneumograph.
  • 2.2. Heart rates decrease linearly with decreasing temperature.
  • 3.3. Submergence in normoxic and hypoxic water at 10°, 15°, and 20°C results in bradycardia which is more pronounced in hypoxic water.
  • 4.4. At 5°C one newt exhibited the above pattern, but bradycardia was not exhibited by the other newt during normoxic submergence.
  • 5.5. Diminishing heart rates are probably due to oxygen deficiency, not immersion alone.
  • 6.6. Recovery from bradycardia in air is rapid and not linked with resumption of aerial breathing.
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16.
  • 1.1.|Resting metabolic rate of laboratory rabbits kept indoors is susceptible to seasonal fluctuations and is higher in winter than in summer.
  • 2.2.|Thermoneutral zone of rabbits under these conditions may shift downwards in winter and upwards in summer.
  • 3.3.|Both of these adjustments in thermoregulation seem to be related to the seasonally changing photoperiod.
  • 4.4.|Dehydration does not influence these thermoregulatory adaptive changes.
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17.
  • 1.1. Pineapple stem extract, consisting of a mixture of the protease bromelain and sulphhydryl protease inhibitors, was fractionated by gel permeation chromatography.
  • 2.2. Inhibitor-containing fractions were further resolved by ion exchange chromatography on DEAE-cellulose, giving 12 chromatographically distinct inhibitory fractions.
  • 3.3. These 12 inhibitory fractions all show an inhibition specificity towards bromelain.
  • 4.4. Reduction, S-carboxymethylation and refractionation of each of these inhibitory fractions gave, for each fraction, two separated peptides of ca 13 and 40 amino acids in length, respectively.
  • 5.5. The amino acid compositions and the N-terminal sequences of these peptides show the inhibitors to be a closely homologous set. Both the constituent peptides of each fraction are microheterogeneous. Each DEAE-cellulose chromatogram peak contains a co-eluting set of iso-inhibitors.
  • 6.6. Structural microvariations within these isoinhibitors have a minor influence on inhibitor activity towards bromelain.
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18.
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19.
  • 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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20.
  • 1.1. When two male mice fight to establish social rank, the subordinate exhibits marked splenomegaly, reticulocytosis and decreased hematocrit.
  • 2.2. Individuals were isolated at weaning, paired 3 weeks later for two 30-min encounter periods daily for up to 3 weeks.
  • 3.3. After 2 days and 1 week encounter periods, subordinates had significantly decreased levels of hemoglobin in the kidney compared to dominants and controls.
  • 4.4. Subordinates had increased ATP levels in blood after 1, 2 and 3 weeks of encounter, bone marrow erythroid hyperplasia, as well as a substantial increase in the erythropoietin litre and Fe59 incorporation in spleen and blood.
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