Pentobarbital anesthesia: Lack of effect on venous prostaglandins in dogs

Venous prostaglandins A, E, and F were determined by radioimmunoassay in 10 dogs before and one hour after administration of sodium pentobarbital (35 mg/Kg, iv). In the conscious state, PGA was 0.34 ± 0.04 ng/ml (mean ± SE), PGE 0.20 ± 0.01 ng/ml, and PGF 0.25 ± 0.03 ng/ml. During pentobarbital anesthesia, these levels were unchanged (p >0.05). Thus, pentobarbital anesthesia had no effect on peripheral venous prostaglandin levels.     

Developmental biochemistry of cotton seed embryogenesis and germination. VII. Characterization of the cotton genome.

The DNA of cotton, Gossypium hirsutum, has been characterized as to spectral characteristics, buoyant density in CsCl, base composition, and genetic complexity. The haploid genome size is found to bo 0.795 pg DNA/cell. However, the amount of DNA per cell in the cotyledons increases during embryogenesis to an average ploidy level of 12N in the mature seed cotyledons. Reassociation kinetics indicate that this increase is due to endoreduplication of the entire genome.Non-repetitive deoxynucleotide sequences account for approximately 60.5% of the cotton genome ($\text{C}{}_0\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}$pure⁵ = 437); highly repetitive sequences (> 10,000 repetition frequency) constitute about 7.7% of the genome. ($\text{C}{}_0\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{pure}\text{= 4.6 × 10}{}^{\mathrm{?4}}$) and intermediately repetitive sequences constitute the remaining 27% of the genome ($\text{C}{}_0\text{t}{}_{\mathrm{<mtext>1</mtext><mtext>2</mtext>}}\text{pure}\text{= 1.46}$). Hybridization of ¹²⁵I-labeled cytoplasmic ribosomal RNA to whole-cell DNA on filters and in solution indicate approximately 300 to 350 copies of the rRNA cistrons per haploid genome.The interspersion of repetitive sequences that reassociate between C₀t values of 0.1 and 50 with non-repetitive sequences of the cotton genome has been examined by determining the reassociation kinetics of DNA of varying fragment lengths and by the electron microscopy of reassociated molecules. About 60% of the genome consists of non-repetitive regions that average 1800 base-pairs interpersed with repetitive sequences that average 1250 base-pairs. Approximately 20% of the genome may be involved in a longer period interspersion pattern containing non-repetitive sequences of approximately 4000 base-pairs between repetitive sequences. Most of the individual sequences of the interspersed repetitive component are much smaller than the mass average size, containing between 200 and 800 base-pairs. Sequence divergence is evident among the members of this component.Highly repetitive sequence elements that are reassociated by a C₀t value of 0.1 average 2500 base-pairs in length, appear to have highly divergent regions and do not appear to be highly clustered. A portion of this highly repetitive component reassociates by C₀t = 10^?4, zero-time binding DNA, and accounts for less than 3% of the genome. At least a third of these sequences appear by electron microscopy to be intramolecular duplexes (palindromes) of 150 to 200 base-pairs and to occur in clusters.     

Adrenal inhibition of maternal behavior in virgin female rats.

The role of the adrenal gland in suppressing the onset of maternal behavior in virgin female rats was investigated. Virgin female rats were either ovariectomized, adrenalectomized, or subjected to the combined operation and tested for the induction of maternal behavior by being exposed to young pups. Females that were both ovariectomized and adrenalectomized 4 weeks prior to testing exhibited significantly shorter latencies to the onset of maternal behavior than that of females subjected to either ovariectomy or adrenalectomy alone. Replacement of either estrogen or progesterone in the group that was both adrenalectomized and ovariectomized resulted in a prolongation of the average latency to become maternal. The results indicated that both estrogen and progesterone can act to inhibit the onset of maternal behavior and that the adrenal gland may act to suppress the onset of such behavior by supplying an extra-ovarian source of endogenous progesterone and estrogen.     

The developmental biochemistry of cotton seed embryogenesis and germination. VI. Levels of cytosol and chloroplast aminoacyl-tRNA synthetases during cotyledon development.

The separation of isotransferring aminoacyl-tRNA synthetase activities (amino acid: tRNA ligases, EC 6.1.1.x) for several amino acids extracted from tissues of embryonic and germinating cotton seeds was carried out by DEAE-cellulose column chromatography. Evidence was obrained that the separated activities represent discrete enzymes, and could be defined as cytosol or chloroplast enzymes by several criteria. The levels of the cytosol enzymes per cell were found to be constant in germinated and ungerminated cotyledons. Chloroplast enzymes were found to be present in immature embryonic cotyledons and in roots at constant levels relative to the cytosol enzymes, but found to increase markedly in germinating cotyledons. This increase takes place to the same extent in etiolated cotyledons as in greened cotyledons indicating that the chloroplast synthetase increase is analogous to the simultaneous increase in chloroplast tRNA and rRNA which also is not light dependent. The separated cytosol and chloroplast enzymes show varying degrees of specificity for isoaccepting tRNA species from homologous and heterologous sources.     

Subcellular fractionation of pig platelets

Subcellular components were obtained from pig platelets, disrupted by means of a French press and separated into 4 primary fractions. The granule fraction (10 000 g) was subjected to a sucrose gradient fractionation. Primary fractions and the granule subfractions were studied electron microscopically and biochemically by following the distribution of markers of membranes, lysosomes of α-granules, mitochondria and dense granules. With this technique of platelet homogenization, 80% of the serotonin and 93% of the β-N-acetylglucosaminidase were found to be particulate. In the gradient, mitochondria were sharply banded in a fraction (density 1.16–1.17) having a specific activity 10–100 times higher than the other fractions of the gradient. Serotonin-containing granules were found in a pellet of density greater than 1.27 and contained 60% of the serotonin and adenine nucleotides of the granule fraction. The lysosome markers that were monitored, acid phosphatase and β-N-acetylglucosaminidase, exhibited different distribution patterns. Acid phosphatase showed the highest specific activity in the microsomal fraction with only 2.8% in the granule fraction, and this latter amount also appeared to be associated with membranes upon further fractionation. β-N-Acetylglucosaminidase was present in both the granule fraction and in the microsomal fraction with nearly the same specific activity. However, that present in the granule fraction was clearly associated with granules that distributed over a wide range of densities on a sucrose gradient. The calcium distribution was followed to attempt to determine its subcellular location; 19% was found in the same subfraction as the serotonin-containing granules, but at least 50% of the particulate calcium was associated with granules distinctly separate from the storage granules.     

Partial purification of active delta and epsilon subunits of the membrane ATPase from escherichia coli

We have partially purified active delta and epsilon subunits of the E. coli membranebound Mg²⁺ -ATPase (ECF₁). Treating purified ECF₁ with 50% pyridine precipitates the major subunits (α, β, and γ) of the enzyme, but the two minor subunits (δ and ϵ), which are present in relatively small amounts, remain in solution. The delta and epsilon subunits were then resolved from one another by anion exchange chromatography. The partially purified epsilon strongly inhibits the hydrolytic activity of ECF₁. The epsilon fraction inhibits both the highly purified five-subunit ATPase and the enzyme deficient in the δ subunit. The latter result indicates that the delta subunit is not required for inhibition by epsilon. By contrast, two-subunit enzyme, consisting chiefly of the α and β subunits, was insensitive to the ATPase inhibitor, suggesting that the γ subunit may be required for inhibition by epsilon. The partially purified delta subunit restored the capacity of ATPase deficient in delta to recombine with ATPase-depleted membranes and to reconstitute ATP-dependent transhydrogenase. Previously we reported (Biochem. Biophys. Res. Commun. 62:764 [1975]) that a fraction containing both the delta and epsilon subunits of ECF₁ restored the capacity of ATPase missing delta to recombine with depleted membranes and to function as a coupling factor in oxidative phosphorylation and for the energized transhydrogenase. These reconstitution experiments using isolated subunits provide rather substantial evidence that the delta subunit is essential for attaching the ATPase to the membrane and that the epsilon subunit has a regulatory function as an inhibitor of the ATPase activity of ECF₁.     

A multi-criteria decision-making model for classifying wood products with respect to their impact on environment

Background, aim and scope  

Although life cycle assessment is frequently used in scientific studies of product comparison, many practitioners are looking for improvements in the normalisation, grouping and weighting of life cycle inventory results. Local conditions, which are well known to local experts, are very important to these steps. The goal of this work was to develop a computer-based decision support system for classifying wood products according to their influence on the environment in their whole life cycle. The model specifically addresses local conditions in the Republic of Slovenia and was developed by Slovenian experts.     

Radioimmunoassay of androsterone and androsterone-3-sulfate in plasma

Details of a sensitive and specific radioimmunoassay for androsterone (1) and androsterone sulfate in plasma have been presented. Benzene extracts of plasma were chromatographed on a lumina to isolate the androsterone fraction either (a) directly after extraction (A) or (b) after solvolysis (AS). Following treatment with rabbit anti-A-17-BSA, antibody bound steroid was precipitated by ammonium sulfate. Androsterone concentrations in normal male plasma averaged 57 ± 24 (S.D.) ng/dl, range 35–135 ng/dl and for normal women, 44 ± 21 (S.D.) ng/dl, range 18–98 ng/dl. Androsterone sulfate concentrations were: males 55 ± 28 μg/dl (range 10–114 μg/dl); premenopausal females 52 ± 31 μg/dl (range 16–318 μg/dl).     

Early and late replicative chromosomal banding patterns of Gallus domesticus.

Early and late replicating chromosomal banding patterns of Gallus domesticus were investigated by cell synchronization and incorporation of 5'-bromodeoxyuridine during early and late DNA synthesis. The early replicating chromosomal banding patterns observed, as revealed by either acridine orange or Hoechst 33258/propidium iodide staining, were similar to the structural G-banding patterns obtained by trypsin digestion and Giemsa staining. Late replicating chromosomal banding showed extensive reverse band complementarity to the G-banding pattern. Cell synchronization increased the number of prometaphase and metaphase plates available for analysis. G-banding obtained by Hoechst 33258/propidium iodide staining was investigated due to the fact that it is compatible with chromosomal in situ hybridization procedures that use nonisotopically-labeled DNA probes. Standard replicative G-banded and R-banded idiograms, as obtained after cell synchronization, are proposed.