Purification and characterization of vitellogenin from the American cockroach,Periplaneta americana

• 1.1. Vitellogenin (VG) was isolated and purified from the hemolymph of female American cockroaches.
• 2.2. The purification method used in this study comprises two steps: the first step is based on the method originally developed for purifying lipophorin from hemolymph, and the second step is the separation of VG from lipophorin by a KBr density gradient ultracentrifugation.
• 3.3. The purified VG was characterized according to molecular weight, substructure, shape and size, and lipid composition.
• 4.4. The VG molecule is almost globular in shape with the diameter of about 15.5 nm and is indistinguishable from lipophorin in shape and size.
• 5.5. The native molecular weight determined by light scattering method was 560 kDa.
• 6.6. The VG consists of four subunits with molecular weights of approximately 102, 81, 49 and 40 kDa, respectively.
• 7.7. VG is a lipoprotein and comprises 92% protein and 8% lipid.
• 8.8. Major lipid components were found to be diacylglycerol (25%) and phospholipids (71%).

     

Cellular and intracellular localization of catalase and acid phosphatase in the midgut of Lumbricus terrestris L.: A cell fractionation study

• 1.1. Cellular and intracellular localization of catalase and acid phosphomonoesterase in the midgut of Lumbricus terrestris was studied by use of tissue fractionation.
• 2.2. At least 60–70% of the catalase resides in the chloragocyte cytosol and the remaining 30–40% resides in gut epithelium peroxisomes.
• 3.3. One of the main functions of the chloragocyte catalase is probably scavenging for H₂O₂ arising from the interaction between blood heme-protein and oxygen.
• 4.4. A simple method for the histochemical detection of cytosol catalase is proposed.
• 5.5. About 10% of the gut acid phosphatase resides in chloragocyte lysosomes. The chloragosomes contain no acid phosphatase.

     

Evidence for extracellular deamination of adenosine in the rat heart

• 1.1. In rat heart perfused with adenosine (10⁻⁶M), dilazep (10⁻⁴M) inhibited incorporation of adenosine into nucleotides (an index of nucleoside transport and phosphorylation) to a greater extent (70%) than metabolism to inosine and uric acid (40%) and actually increased the recovery of inosine to 30% of the adenosine infused.
• 2.2. Extrapolating for complete inhibition of transport suggested that 60% of adenosine metabolism was intracellular and 40% extracellular.
• 3.3. Static incubations of atria also gave an estimate for extracellular metabolism of 40%.
• 4.4. Adenosine deaminase was localised by immunocytochemistry to the extracellular surface of endothelial cells of small coronary arteries.
• 5.5. Extracellular deamination may explain the lack of effect of nucleoside transport inhibitors on responses to adenosine in rat heart.

     

The effect of Cryptocotyle lingua infection on the blood volume of Littorina littorea

• 1.1. Blood volumes of uninfeeted and parasitized individuals of L. littorea have been measured using inulin dilution.
• 2.2. Uninfected specimens have a blood volume of 64% and parasitized specimens a blood volume of 38% of the flesh weight.
• 3.3. Two different methods of inulin analysis give essentially similar results.

     

Laboratory studies on the oxygen consumption of the marine teleost,Lichia amia (Linnaeus, 1758)

• 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.

     

Time related changes in the free amino acid pool of the sea anemone,Bunodosoma cavernata,during salinity stress

• 1.1. The sea anemone, Bunodosoma cavernata, is a relatively eurybaline cnidarian tolerating salinities from 12 to 40%.
• 2.2. Taurine, glutamic acid and aspartic acid all showed some increases with increased salinity.
• 3.3. The amino acid showing the greatest accumulation under high salinity conditions was β-alanine which increased 28-fold from 1.5 to 41.9 μmol/g dry weight when salinity was raised from 26 to 40%.
• 4.4. When B. cavernata was subjected to increased salinity, β-alanine was rapidly accumulated and reached maximum levels within 4 days.
• 5.5. When salinity was dropped from 36 to 26%0, β-alanine concentrations dropped from 15 to 2 μmol/g dry weight in 2 days.

     

Difference in the specific activity of tritium labelled water in blood,urine and evaporative water in rabbits

• 1.1. After a single injection of tritium labelled water (THO) into rabbits the specific activity was measured in blood, urine and evaporative water.
• 2.2. The specific activity in urine was similar to that in blood, the specific activity in pulmocutaneous evaporate was 5–8% below that of blood.
• 3.3. The permeability coefficient of the urinary bladder wall for THO was 44 ± 11 cm/sec × 10⁻⁶.
• 4.4. Maximum differences in the specific activity between blood and urine due to the accumulation of urine in the bladder were calculated as up to 1.8%.
• 5.5. In the state of equilibrium the specific activity in urine water, but not in evaporative water. can be used for the estimation of total body water.

     

A fetal-maternal shift in the oxygen equilibrium of hemoglobin from the viviparous caecilian,Typhlonectes compressicauda

• 1. The equilibria and kinetics of oxygen binding by blood and hemoglobin from adult and fetal caecilians,Typhlonectes compressicauda, have been measured.
• 2. The oxygen affinity of fetal blood is higher than that of adult blood.
• 3. Electrophoresis of adult and fetal hemoglobins suggests that they may be identical: a major and minor component occurs in each.
• 4. Adult and fetal hemoglobins have identical oxygen equilibria. Stripped hemoglobins have a high oxygen affinity and no Bohr effect between pH 6.5 and 10.0. An “acid”, reversed Bohr effect is present below pH 6.5. The addition of 1 mM ATP reduces the oxygen affinity markedly and produces a moderate, normal Bohr effect.
• 5. The major nucleoside triphosphate in fetal and adult erythrocytes is adenosine triphosphate: about 10% of the nucleoside triphosphates is guanosine triphosphate. Adult erythrocytes contain 3 times as much ATP as do the fetal erythrocytes.
• 6. The fetal to maternal shift in the oxygen equilibrium is mediated entirely by the difference in ATP content of the maternal and fetal red blood cells.

     

Proteolytic cleavage of band 3 protein in relation to anion transport in fish (Oncorhynchus mykiss) red blood cells

• 1.1. The effects of trypsin and chymotrypsin on HCO₃⁻/Cl⁻ exchange through red blood cell membranes of humans and trout were studied.
• 2.2. To measure the anion exchange we used a right-angle light-scattering technique by applying the Jacobs-Stewart cycle in ammonium solution and the osmotiration method at constant cell volume.
• 3.3. The Cl⁻ flux in human red blood cells remained unaltered after treatment with external trypsin and chymotrypsin while in trout red blood cells the flux decreased.
• 4.4. This partial inhibition of anion transport in fish, ranging from 30 to 40%,suggest that one or several of the cleavage sites in band 3 protein, essential for anion transport function, are exposed in fish red blood cells.
• 5.5. In human red blood cells the fragments of band 3 which are affected by proteolytic digestion, retain their tertiary structure because there is no influence on anion transport.

     

The role of citrate derived from glucose in the acetylcholine synthesis in rat brain synaptosomes

• 1.1. Synaptosomes utilizing glucose or glucose plus malate produced citrate with rates of 2.4 and 7.8 nmol/hr/mg of protein, respectively.
• 2.2. (−)Hydroxycitrate increased citrate net synthesis 4 times and inhibited acetylcholine synthesis by 40%.
• 3.3. Oxygen and glucose consumption as well as lactate and CO₂ production were not changed by this inhibitor.
• 4.4. (−)Hydroxycitrate inhibited utilization of exogenous citrate in synaptosomes by 50%.

     

Skin blood flow in the Wistar-Kyoto rat and the spontaneously hypertensive rat

• 1.1. Using laser Doppler techniques in man, we have previously demonstrated differences in skin blood flow properties at sites with primarily nutritive (NUTR) perfusion, such as the elbow or knee, as compared to sites such as the finger pulp, with predominantly arteriovenous anastomotic (AVA) perfusion.
• 2.2. Basal and heat stimulated flow is greater at AVA sites. In man, blood pressure changes are reflected primarily by changes at AVA rather than NUTR sites.
• 3.3. These blood pressure induced changes affect the red blood cell velocity (VEL) component at AVA sites more than microvascular volume (VOL).
• 4.4. Given these findings in man, we decided to compare skin blood flow properties in a suitable animal model.
• 5.5. We chose the Wistar-Kyoto (WKY) and Spontaneously Hypertensive Rat (SHR) strains, in view of the marked difference in systemic blood pressure in these two related strains.
• 6.6. Skin blood flow varied considerably at different skin sites in the rats. Skin sites with hair covering, on the back and at the base of the tail, showed low basal and heat stimulated blood flow.
• 7.7. In contrast, the plantar surface of the paw behaved similarly to the finger or toe pulps in man, with 3–4-fold higher basal flow than the hair covered areas and a 7–8-fold rise with local heating to 44°C.
• 8.8. Furthermore, there was a 25% greater blood flow at the plantar paw surface in the SHR rats as compared to the WKY rats, corresponding to the 25% higher systemic blood pressure in these animals.
• 9.9. The heat induced increase in flow at the plantar surface of the paw was primarily a result of a marked increase in VEL rather than VOL.
• 10.10. The higher flow at this site in SHR as compared to WKY rats was likewise ascribable to an increase in VEL, VOL being equivalent in the two strains.

     

The effect of d2o on glycolysis by rat hepatocytes

• 1.1. The effect of incorporating D₂O into the incubation medium on glycolysis and gluconeogenesis by hepatocytes from fasted rats was examined.
• 2.2. The substitution by heavy water, D₂O, at concentrations from 10 to 40%, stimulated glucose uptake, lactate production and CO₂ yields from glucose. At 10 mM glucose, 40% D₂O doubled glucose uptake, increased CO₂ production by 40%, and increased lactate production by 350%.
• 3.3. The stimulation of lactate production decreased at higher glucose concentrations, but was still substantial even at 80 mM glucose.
• 4.4. There was no effect on CO₂ production above glucose concentrations of 30 mM.
• 5.5. Ten percent D₂O showed little inhibition of lactate uptake, its oxidation and gluconeogenesis. At 40% D₂O the inhibition ranged from 10 to 20%.
• 6.6. No effect of D₂O on the rate of glucokinase or glucose-6-phosphatase was observed.
• 7.7. The concentration of fructose, 2,6-P was not affected by D₂O

     

Evaporative water loss and uptake in juvenile and adult Salamandra salamandra (L.) (Amphibia: Urodela)

• 1.1. Both juveniles and adults of this rare salamander were studied.
• 2.2. The rate of evaporative water loss increased with temperature and at lower humidities.
• 3.3. At all four temperatures and three humidities studied, adults lost water at a lower rate than juveniles.
• 4.4. Aggregating juveniles reduced water loss especially at lower moisture.
• 5.5. The rate of water uptake was greater in juveniles than in adults.
• 6.6. Juveniles were capable of absorbing moisture from moist soil even at 40% saturated soil.

     

Measurement of blood flow in the skin and oral mucosa of the rhesus monkey (Macaca mulatta) using laser doppler flowmetry

• 1.1. It is generally assumed that oral blood flow is higher than that of skin, and invasive methods to measure blood flow support this view.
• 2.2. However, it was not known whether this finding would be confirmed by laser Doppler flowmetry, which is a noninvasive method to measure blood flow.
• 3.3. The purpose of this study was to compare blood flow in oral and skin regions of the rhesus monkey using laser Doppler flowmetry.
• 4.4. The results demonstrated that blood flow was significantly higher in oral regions as compared to facial skin (P < 0.05).
• 5.5. This finding is most likely related to the more abundant capillary supply in oral mucosa as compared to skin.

     

Hematology and blood chemistry of the marsh harrier (Circus aeruginosus)

• 1.1. This study deals with the hematological and blood chemistry of 13 adult marsh harriers (Circus aeruginosus).
• 2.2. No significant differences were observed between male and female groups in any of the parameters.
• 3.3. The value of white blood cells was 14,677/mm³ heterophils and lymphocytes, these being the most abundant cellular type (81.42 and 12%, respectively).
• 4.4. Urea and uric acid are present in approximately similar proportions, though birds are said to be uricotelic.
• 5.5. The cholesterol concentration values determined in our study, are higher than those reported in most other birds.

     

Urea excretion rates and waste nitrogen concentrations during metamorphosis of Xenopus laevis Daudin

• 1.1. Serum urea, ammonia concentrations in the blood and excretion were measured in tadpoles of different stages and juveniles of Xenopus laevis.
• 2.2. The urea excretion rate was determined with the help of injected ¹⁴C-urea.
• 3.3. Urea concentrations are higher during metamorphic climax and at the end of metamorphosis than during prometamorphosis.
• 4.4. Blood ammonia levels remain rather constant throughout metamorphosis.
• 5.5. Coincidentally, the relative amount of urea in the blood increases.
• 6.6. The ¹⁴C-urea excretion rates slow down from very high values (48%/hr) at the beginning of prometamorphosis to low rates (5%/hr) in newly metamorphosed animals.
• 7.7. This means that during metamorphosis not only is the possibility of urea production established. but there is a capacity to retard and store urea to some extent.

     

Purification and characterization of hatching enzyme of the pike (Esox lucius)

• 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.

     

Oxygen consumption,body temperature and heart rate in the coati (Nasua nasua)

• 1.1. Coatis are chiefly diurnal, showing marked nycthemeral variations of body temperature and oxygen uptake.
• 2.2. The thermoneutral zone extends from 25–33°C; the basal metabolic rate is about 40% below the value predicted from body mass.
• 3.3. Thermoregulation in cold is excellent, partly due to decreasing thermal conductance at falling ambient temperatures.
• 4.4. Exposure to temperatures above 35°C is endured for only short periods.
• 5.5. Basal heart rate is reduced to about 70% of the predicted level. The contribution of heart rate to increased oxygen demands at falling ambient temperatures is rather low.
• 6.6. The measured physiological characteristics of coatis are discussed with regard to the high mobility and the wide distribution range of these procyonids.

     

The precipitation of human IgG and its subunits with heparin

• 1.1. About 40% of IgG is precipitated when heparin is added to human plasma at pH 5.4, while only a little IgM and no IgA are precipitated.
• 2.2. The precipitation of purified IgG by heparin is pH-dependent and follows a sigmoid curve between pH 7.0 and 5.0.
• 3.3. The precipitate has a constant molar ratio heparin: IgG, independent of pH or the amount of heparin that is added.
• 4.4. The precipitate does not redissolve at high heparin concentrations.
• 5.5. The heavy chains of IgG precipitate also at pH 5.4, but this precipitate redissolves in excess heparin.
• 6.6. Light chains do not precipitate and the F_ab and F_c fragments are only partly precipitated.

     

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