Neonatal serum bilirubin levels following the use of prostaglandin E2 in labour

A prospective study of 447 labours and the resulting neonates failed to reveal a significant difference between the mean serum bilirubin concentrations on the third and sixth day following spontaneous, accelerated or induced labour. A similar incidence of neonatal jaundice (bilirubin concentrations of 10 mg/100 or more) was found in the studied groups. However, there was a tendency for neonates born after accelerated or induced labour to have slightly higher bilirubin levels than those born after spontaneous labour. No strong dose dependent effect on the level of bilirubin concentration following Prostaglandin E₂ induced labour was demonstrated.     

Quantitative analysis of solubilized methane in refuse leachate

To obviate problematic gas phase analyses, a rapid, simple method was developed for the quantitative determination of methane release from continuously perfused, passively vented, heterogeneous laboratory landfill models.     

Effects of semi-starvation on the total body composition and absorptive function of the small intestine of the young adult female rat.

Sixteen female rats aged about 80 days and with a mean body weight of 175 g were fed 40% of their ad libitum intake of a laboratory chow. They were killed and analysed for water, protein, lipid and ash after 9, 21-5, 30-2 and 38-8% of body weight had been lost. Compared to a control group of four animals, the 38-8% group lost 13 g or 34% of their protein. The animals in the 21-5, 30-2 and 38-8% groups lost 7-5 g or 87% of their lipid leaving only 1-1 g of lipid. The percentage protein in the body was little affected by body weight loss but lipid decreased from 5 to 1%. In another experiment with 26 rats of 205 g mean body weight and aged about 115 days, absorption rates by the small intestine were measured in vivo after variable weight losses between 0 and 39%. D(+)-Glucose uptake was increased by about 70% in those animals which had lost only 5% of body weight and this increased uptake was retained in those rats which had lost up to 39% of body weight. The absorption of L-leucine was not affected by the decline in body weight compared to the controls but relative to body weight, the ability of the intestine to absorb increased. In the same animals, the wet and dry weights of the small intestine declined slightly faster than body weight and the length of the small intestine tended to decrease slightly with increasing loss of body weight.     

Trypsin cleavage of the alpha-subunit of beef heart F1-ATPase abolishes ATP synthesis and ATP-driven energy-transduction capabilities

Previous work has shown that mild trypsin treatment eliminates energy-transduction capability and tight (non-exchangeable)nucleotide binding in beef heart mitochondrial F1-ATPase (Leimgruber, R.M. and Senior, A.E. (1976) J. Biol. Chem. 251, 7103-7109). The structural change brought about by trypsin was, however, too subtle to be identified by one-dimensional sodium dodecyl sulfate polyacrylamide gel electrophoresis, and was not defined. In this work we have applied two-dimensional electrophoresis (isoelectric focussing then sodium dodecyl sulfate polyacrylamide gradient electrophoresis) to the problem, and have determined that the alpha-subunit of F1 is altered by the mild trypsin treatment, whereas no change was detected in beta-, gamma-, delta- or epsilon-subunits. Binding of ADP to the trypsin-treated F1 was compared to binding to control enzyme over a range of 0-40 muM ADP in a 30 min incubation period. There was no difference between the two enzymes, KADPd in Mg2+ -containing buffer was about 2 muM in each. Since the tight (nonexchangeable)sites are abolished in trypsin-treated F1, this shows that tight exchangeable ADP-binding sites are different from the tight nonexchangeable ADP-binding sites. There was no effect of trypsin cleavage of the alpha-subunit on beta-subunit conformation as judged by aurovertin fluorescence studies. The cleavage of the alpha-subunit which occurred was judged to occur very close to the C- or N-terminus of the subunit and constitutes therefore a small and specific chemical modification which abolishes overall function in F1 but leaves partial functions intact.     

Membrane interactions of the putative fusion peptide (MFalphaP) from fertilin-alpha,the mouse sperm protein complex involved in fertilization

Mammalian fertilization depends upon successful binding and fusion between the membranes of the spermatozoon and the oocyte. These processes are thought to be mediated by a series of protein-protein interactions in which sperm antigens known as fertilins are thought to play a key role. Using a recently developed fluorescence technique, the interactions of the oligopeptide sequence corresponding to the fusogenic domain of mouse fertilin-alpha (MFalphaP) and phospholipid vesicles have been investigated. Following stopped-flow mixing, MFalphaP bound rapidly to phospholipid membranes in a co-operative manner with a Hill coefficient of 2.4 and binding rate constants in excess of 1000 s-1. The co-operative nature of the binding process is suggested to represent evidence of a structural mechanism to prevent egg fertilization by immature spermatozoa. The subsequent membrane insertion was found to take place over a longer time period (with rate constants of up to 6.3 s-1), and was linear with respect to peptide concentration. Comparison of these processes with similar time-resolved circular dichroism measurements revealed that changes in peptide secondary structure were very rapid. Fourier transform infrared spectroscopy measurements confirmed changes in the secondary structure of MFalphaP during interaction with PC phospholipid membranes, indicating that the peptide is mainly present in a beta-structure with a small proportion of alpha-helix. These results are consistent with the hypothesis that fertilin-alpha is the fusogenic species with an important role in fertilization.     

Books

Industrial Ecology of the Automobile: A Lifecycle Perspective, by Gregory A. Keoleian, Krishnendu Kar, Michelle M. Manion, and Jonathan W. Bulkley
Industrial Ecology and the Automobile, by Thomas E. Graedel and Braden R. Allenby     

Control/promotion of the refuse methanogenic fermentation

Although practiced for more than 7 millennia, the landfill disposal of refuse has, as yet, with few exceptions, been merely regarded as a low-cost disposal option and its exploitation potential has been largely ignored. Today, however, a number of possibilities are under consideration including the production of energy, chemical feedstock, value-added chemicals, carbon dioxide and protein; the use of refuse as an anaerobic filter for the co-disposal of industrial wastewater and sludge; and the restoration of impoverished soils by fresh or composted refuse addition. Development of these technologies, however, necessitates a comprehensive understanding of the fundamental microbiology and biochemistry of refuse catabolism. Existing fundamental knowledge underpinning these technologies will be considered in a series of review articles. In the first, control/exploitation of the solid-state refuse methanogenic fermentation is examined with specific reference to the effects of first-tier variable manipulations.