Comparative analysis of dufour's gland secretions of two carpenter bees (xylocopinae: anthophoridae) with different nesting habits

• 1.1. The chemistry and function of Dufour's gland secretions of two carpenter bees were studied.
• 2.2. Dufour's gland of Proxylocopa olivieri, a ground nesting bee, produces long chain hydrocarbons that are utilized to line its brood cells and are mixed with its bee bread.
• 3.3. Dufour's gland secretion of Xylocopa sulcatipes, on the other hand, is dominated by ethyl eicosanoate and ethyl docosanoate accompanied by the corresponding methyl esters and high boiling hydrocarbons.
• 4.4. This wood nesting bee apparently does not use Dufour's gland secretion to line its nest.
• 5.5. The relationship between the respective chemistry and function of Dufour's gland secretion and the nesting ecology of the two bees is discussed.

     

The influence of optic nerve section on blood metabolite levels in Carcinus maenas (Crustacea: Brachyura)

• 1.1. Blood metabolite levels were assayed in Carcinus maenas as an indicator of the functioning of the hyperglycemic hormone, HGH, secreted by the crab's eyestalk neuroendocrine tissue.
• 2.2. Bilateral eyestalk ablation eventually resulted in a hypoglycemic response after 2–3 days.
• 3.3. Bilateral optic nerve section produced a significant, long-term hypoglycemic response suggesting that release of HGH from the eyestalk sinus gland is controlled, via a promotive neural pathway, by the CNS and probably by the cerebral ganglia.
• 4.4. Injection of eyestalk extract into operated crabs consistently produced significant, short-term hyperglycemia.

     

Alteration of the protein composition of bothrops jararaca venom and venom gland by isoproterenol treatment

• 1.1. The protein composition of Bothrops jararaca venom and venom gland was analyzed through SDS-PAGE, after isoproterenol (IPR) treatment.
• 2.2. Some proteins (47, 48, 57 and 72 kDa) were detected in the gland homogenate from the control but not from the IPR-treated samples.
• 3.3. Three proteins (26.5, 44.5 and 53 kDa) were detected in the venom gland from IPR-treated snakes but not from the venom gland from the control.
• 4.4. In the venom samples proteins of 41 and 74 kDa were detected only in the IPR treated samples, while proteins of 17 and 28 kDa were detected only in the control.
• 5.5. The biological activity of the venom did not change with IPR treatment.

     

Biochemical evidences for two sibling species of genus Myliobatis (chondrichthyes: myliobatidae) in South Brazil

• 1.1. Two morphotypes of Myliobatis from the demersal fishery off the Rio Grande (Brazil) were studied.
• 2.2. Thirty-two alleles were detected and resolved by 27 loci.
• 3.3. Nei's measure of genetic identity was 0.8306 and Thorpe's similarity was 0.6990. Mean heterozygosities observed were 0.1327 for the “DE” morphotype and 0.0409 for the “DL” morphotype.
• 4.4. Seven loci were fixed differently in the two taxa studied. This indicates the existence of a barrier to gene-flow between them, showing that both morphotypes belong to different species.
• 5.5. Jaccard's measure of similarity was calculated and a phenogram with the two morphotypes and M. freminvillii was constructed using isoelectric focusing of total soluble proteins. This showed a higher similarity between the two morphotypes of Myliobatis than M. freminvillii.

     

Phosphatase activity in the hepatopancreas of Helix aspersa

• 1.1. Phosphatase acid (PhA) activity in the digestive gland (hepatopancreas) of the common garden snail Helix aspersa has been investigated using cytochemical methods.
• 2.2. All the cells composing this gland show PhA activity, the distribution pattern differing according to the cell type.
• 3.3. The digestive cells show the most widely distributed reaction product (brush border, phagolysosomes, multivesicular bodies and autophagic vacuoles).
• 4.4. In the excretory cells this activity appears in large sacs, while in the calcium cells the reaction product is abundant in the calcium granules.
• 5.5. Cellular digestion processes performed by each of these cell types is discussed together with their role in the detoxification of heavy elements derived from the environment.

     

Malate dehydrogenase isoforms from ribbed mussel (Modiolus demissus) gill tissue

• 1.1. The malate dehydrogenase (MHD) activity from the ribbed mussel gill is polymorphic with two distinct mitochondrial forms (M1 and M2) and five forms that could be resolved from cytosolic extracts (C1 to C5) by DEAE-cellulose chromatography and starch gel electrophoresis.
• 2.2. Two of the cytosolic forms (C3 and C4) may represent interchangeable conformational states.
• 3.3. With kinetic analysis there appear to be three distinct cytosolic forms (C1, C2 and C3–C4), with C2 possibly behaving as a heterodimer.
• 4.4. The identity of C5 is uncertain.
• 5.5. The forms isolated from the mitochondria (M1 and M2) exhibited lower apparent K_ms for oxaloacetate (OAA) than the cytosolic forms.
• 6.6. For all isozymic forms, the apparent K_ms for OAA increased as the pH increased between pH 6 and 9
• 7.7. Increasing the salt concentration raised the K_m for OAA for all forms.
• 8.8. The mMDHs were more sensitive to inhibition by NaCl than the cMDHs.
• 9.9. Representative cMDH (C1) and mMDH (M2) isozymes exhibited substrate inhibition by high concentrations of OAA with the mMDH possessing lower K_is for substrate inhibition than the cMDH at each pH tested.
• 10.10. Differences and similarities in K_m app. for OAA at the different pHs and salt concentrations indicated that C1, C2 and C3–C4 and C5 were distinct forms, that M1 and M2 were distinct but very similar to each other, and that C1, C2, C3–C4 and C5 were distinct from M1 and M2.

     

Evidence of an egg-laying factor in the prostatic secretions of Helix aspersa müller

• 1.1. A high percentage (53%) of isolated snails injected with prostate gland homogenates lay eggs.
• 2.2. These egg masses consist of a few eggs which contain many nonviable oocytes.
• 3.3. Preliminary experiments suggest that an egg-laying factor may be present in prostatic secretions.
• 4.4. Snails bred in isolation from hatching, whether injected or not, occasionally lay viable eggs.
• 5.5. This observation shows that self-fertilization or parthenogenesis is, in fact, possible in Helix aspersa Müller.

     

Electrophoretic characterization of a hybrid between Eretmochelys imbricata and Caretta caretta (Cheloniidae)

• 1.1. An intermediate morphotype between Eretmochelys imbricata and Caretta caretta was studied in Praia do Forte, Bahia, Brazil.
• 2.2. Three enzymatic systems were successfully analyzed: SOD, lactate dehydrogenase (LDH) and esterase (EST). Isoelectric focusing of total soluble proteins of muscle and transferrin were shown.
• 3.3. Esterase exhibited nine phenotype patterns, seven in C. caretta and one in the others morphotypes. SOD phenotypes were identical in the three morphotypes. Lactate dehydrogenase and transferrins were characteristic for each species.
• 4.4. Jaccard's measure of similarity was calculated and a phenogram with the three morphotypes were constructed using isoelectric focusing of total soluble proteins.

     

Purification and some properties of an atypical alkaline p-nitrophenylphosphate phosphatase activity from Halobacterium halobium

• 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 K_m 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.

     

Selective activation of carcinogenic aromatic amines to bacterial mutagens in the marine musselMytilus gallopro vincialis

• 1.1. The postmitochondrial fraction of the marine mussel Mytilus galloprovincialis digestive gland activates selectively precarcinogenic aromatic amines, but not precarcinogenic benzo(a]pyrene, to Salmonella typhimurium TA 98 mutagens.
• 2.2. This activation potential is NADPH-dependent, is not inducible by exposure to Diesel 2 oil and a polluted environment, and is inhibited by methimazole.
• 3.3. The characteristics of this activation potential are consistent with the recent finding of the presence of FAD-containing-, and lack ofcytochrome P-450 dependent-, monooxygenase activity in Mytilus edulis.
• 4.4. The presence of such selective potential in marine invertebrate(s) may bring new insight into our understanding of the fate and the effects of carcinogens in the marine environment.

     

Hydrolysis of glycol chitin by chitinolytic enzymes

• 1.1. The hydrolysis of glycol chitin preparations by several β-N-acetylglucosaminidases was monitored colorimetrically with the potassium ferriferrocyanide reagent.
• 2.2. Glycol chitin samples from crab and insect sources varied considerably in chemical composition and susceptibility to enzymatic hydrolysis.
• 3.3. Insect endochitinase preferred crab glycol chitin as substrate while hen's egg white lysozyme preferred commercial glycol chitin.
• 4.4. Insect glycol chitin was well hydrolyzed by both enzymes.
• 5.5. Insect exochitinase did not digest glycol chitin.

     

A comparison of aspartate transcarbamylase activity in juvenile pacific oysters (Crassostrea gigas) when fed various diets

• 1.1. The optimum pH for measurement of aspartate transcarbamylase activity in oyster tissue was determined to be 9.35 while the optimum temperature was 39.5°C.
• 2.2. Aspartate transcarbamylase activity varied significantly over short periods of time (hr) possibly due to fluctuations in the amount of food digested.
• 3.3. The composition of the oyster's diet also affected the levels of aspartate transcarbamylase activity in oyster tissues.
• 4.4. Those oysters fed an egg yolk-starch diet contained significantly lower aspartate transcarbamylase activity than oysters fed an egg yolk-starch-salmon oil diet or a casein-starch-salmon oil diet.
• 5.5. The aspartate transcarbamylase activities in oysters fed Phacedactylum tricornutum or a starch diet were not significantly different from the activities in oysters fed the egg yolk-starch diet.

     

Hemolymph osmoregulation in three species of beetles

• 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.

     

Comparison of the proliferation and differentiation of myogenic satellite cells and embryonic myoblasts derived from the turkey

• 1.1. Embryonic and posthatch turkey skeletal muscle development was compared in in vitro studies using clonal-derived embryonic myoblasts and satellite cells.
• 2.2. Although population doubling times were similar between the two lines (25.4 hr for satellite cells and 26.4 hr for embryonic myoblasts), embryonic myoblasts consistently began log phase growth 24 hr earlier than satellite cells.
• 3.3. Differentiation (fusion) of embryonic myoblasts was maximized by 36 hr in Dulbecco's Modified Eagle's Medium containing 1% horse serum compared with 72 hr for satellite cells.
• 4.4. When administered a serum-free medium which supports proliferation of turkey satellite cells, embryonic myoblasts differentiated to form myotubes.

     

Fatty acid profile of the digestive gland and mantle in the bivalve Macoma balthica

• 1.1. Digestive gland and mantle fatty acids were studied in spring and summer in the bivalve Macoma balthica off the southern coast of Finland. The presence of lipids was also examined histochemically in various clam tissues.
• 2.2. the neutral lipid content of the digestive gland increased ca 4.5-fold during the annual growth period.
• 3.3. Neutral lipid fatty acids of the digestive gland, of which palmitoleic, eicosapentaenoic and palmitic acids were predominant, were clearly distinguished from phospho- and glycolipid fatty acids.
• 4.4. The degree of unsaturation of phospholipid fatty acids was higher in the cold season both in the digestive gland and mantle, mainly due to the titer of eicosapentaenoic acid.

     

Responses of antioxidants and lipid peroxidation in mussels to oxidative damage exposure

• 1.1. The aim of this work was to evaluate the relationships between free radical scavengers and lipid peroxidation in the common mussel Mytilus edulis.
• 2.2. Mussels were exposed to compounds known for their ability to produce free radicals (carbon tetrachloride, CCl₄) and reactive oxygen species via redox cycling (menadione), and the effects on digestive gland, gills and remaining tissues were studied.
• 3.3. Lipid peroxidation parameters and the status of free radical scavengers (glutathione, vitamins A, E and C) were affected more by exposure to menadione than to CCl₄.
• 4.4. The observed changes in the free radical scavengers content are indicative of a role in detoxication of damaging reactive species.

     

Lysosomal acid deoxyribonuclease from vervet monkey livers—II: Enzymic properties

• 1.1. Primate liver lysosomal acid DNase is an endonucleolytic enzyme.
• 2.2. The enzyme has both 3'- and 5'-nucleotidohydrolase activities.
• 3.3. The oligonucleotides produced by DNase are polymers mainly about 30 mononucleotides long.
• 4.4. The Arrhenius plot shows a discontinuity with a transition temperature at 47°C, with an activation energy of 107 kJ/mol below and 67 kJ/mol above this temperature.
• 5.5. The activation enthalpy is 104kJ/mol and the entropy −0.498 kJ/mol/K.
• 6.6. The enzyme is subject to substrate inhibition and the K_m value is 159 × 10⁻³mM DNA-P.

     

Synthesis of reserved polysaccharide from wax esters accumulated as the result of anaerobic energy generation in Euglena gracilis returned from anaerobic to aerobic conditions

• 1.1. Euglena gracilis SM-ZK (a non-photosynthetic mutant), cultured in Koren-Hutner medium, containing glucose, malate and glutamate as the main nutrients, were incubated anaerobiosis for 24 hr, and then returned to aerobic conditions. Wax esters, which were synthesized from paramylon (the reserved polysaccharide) for ATP generation under anaerobiosis (wax ester fermentation) were promptly degraded immediately after the cells were replenished with sufficient O₂. A large part (about 70%) of the decomposed wax esters were converted back to paramylon.
• 2.2. When cells were fed with [1–14C]acetate or [U-¹⁴C]acetate immediately after transfer from anaerobic to aerobic conditions, radioactivity incorporated into paramylon in the cells fed with [U-¹⁴C]acetate was about 1.5-times as high as that with [1-¹⁴C]acetate, proposing that glyoxylate cycle participates in the conversion from wax esters to paramylon.
• 3.3. Paramylon synthesis from [1-¹⁴C]acetate was considerably activated by anaerobic preincubation of cells for several hours.
• 4.4. Isocitrate lyase and malate synthase occurred in cells cultured in Koren-Hutner medium, but the activities were obviously lower than those in cells grown on ethanol. These enzymes were not induced by the anaerobic preincubation.

     

Effects of angiotensin II and bladder condition on hydration behavior and water uptake in the toad,Bufo woodhousei

• 1.1. Water absorption response (WR) behavior and water weight gain were examined in hydrated toads, Bufo woodhousei, treated with angiotensin II (All) or with a control Ringer's solution. The effects of urinary bladder condition (ad lib. bladder urine or empty bladder) were examined concurrently.
• 2.2. Toads treated with All (100μg/100g body weight), spent more time in WR posture and absorbed more water than Ringer's-injected toads.
• 3.3. Toads with empty bladders maintained WR posture for longer periods of time and gained more weight than toads whose bladders were not emptied.
• 4.4. The effects of All and bladder urine on water absorption by B. woodhousei appear to be separate and additive.

     

Multidimensional Proteomics Identifies Declines in Protein Homeostasis and Mitochondria as Early Signals for Normal Aging and Age-associated Disease in Drosophila,

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Highlights

• •Proteomic landscapes of Drosophila somatic and reproductive tissues during aging.
• •Pulsed metabolic labeling determines a decline in protein synthesis with age.
• •Drosophila model of human Parkinson's disease signifies an early-onset decline in protein synthesis.
• •Collapse of proteostasis and mitochondria are early signals for normal aging.