Polyphenolics of Salvia--a review.

Salvia is an important genus widely cultivated and used in flavouring and folk medicines. The genus has attracted great interest so much so that it has been the subject of numerous chemical studies. It is a rich source of polyphenols, with an excess of 160 polyphenols having been identified, some of which are unique to the genus. A large number of these polyphenolic compounds are apparently constructed from the caffeic acid building block via a variety of condensation reactions. The nature of these polyphenols which have been reported is compiled in this report together with some bioactivity data in an effort to show the rapid development in the phytochemistry and the therapeutic applications of the Salvia species.     

Subsite mapping of enzymes. Depolymerase computer modelling.

We have developed a depolymerase computer model that uses a minimization routine. The model is designed so that, given experimental bond-cleavage frequencies for oligomeric substrates and experimental Michaelis parameters as a function of substrate chain length, the optimum subsite map is generated. The minimized sum of the weighted-squared residuals of the experimental and calculated data is used as a criterion of the goodness-of-fit for the optimized subsite map. The application of the minimization procedure to subsite mapping is explored through the use of simulated data. A procedure is developed whereby the minimization model can be used to determine the number of subsites in the enzymic binding region and to locate the position of the catalytic amino acids among these subsites. The degree of propagation of experimental variance into the subsite-binding energies is estimated. The question of whether hydrolytic rate coefficients are constant or a function of the number of filled subsites is examined.     

The origin and evolution of protein superfamilies.

The organization of proteins into superfamilies based primarily on their sequences is introduced: examples are given of the methods used to cluster the related sequences and to elucidate the evolutionary history of the corresponding genes within each superfamily. Within the framework of this organization, the amount of sequence information currently and potentially available in all living forms can be discussed. The 116 superfamilies already sampled reflect possibly 10% of the total number. There are related proteins from many species in all of these superfamilies, suggesting that the origin of a new superfamily is rare indeed. The proteins so far sequenced are so rigorously conserved by the evolutionary process that we would expect to recognize as related descendants of any protein found in the ancestral vertebrate. The evolutionary history of the thyrotropin-gonadotropin beta chain superfamily is discussed in detail as an example. Some proteins are so constrained in structure that related forms can be recognized in prokaryotes and eukaryotes. Evolution in these superfamilies can be traced back close to the origin of life itself. From the evolutionary tree of the c-type cytochromes the identity of the prokaryote types involved in the symbiotic origin of mitochondria and chloroplasts begins to emerge.     

Polymer fractionation in aqueous two-phase polymer systems.

We consider the effects of the addition of poly(ethylene glycol) (PEG) of different molecular weights to aqueous two-phase system of PEG 8000 and dextran 500. The first purpose of this study was to determine the molecular weight partitioning of the polymers themselves so that, for example, aqueous two-phase separations using affinity ligands can be improved. The second purpose was to examine whether this molecular weight partitioning could be predicted by using solution thermodynamic models so that it would be possible to optimize affinity partitioning without extensive laboratory work. Experimentally, we find that, by increasing the PEG concentration of any molecular weight in the feed, the high molecular weight PEG concentration in the dextran-rich phase is reduced. This observation can be used to reduce the loss of expensive ligated PEG used in affinity partitioning. Further, there is generally good agreement between our experimental data and the predictions of a solution thermodynamic model.     

The reaction of protein tryptophanyl residues with reduced nicotinamide adenine dinucleotide. Structure of a model adduct.

This paper describes in detail a simple, light producing and handling system which differs greatly from the commercial unit presently used by most investigators, and which overcomes a number of its disadvantages. The apparatus is designed so that it can easily be substituted for the light producing, dispersing, and collimating section of the commercial photoelectric scanners, with no further changes in the commercial scanners except the substitution of optical flats for the collimating and condensing lenses in the bottom and top, respectively, of the rotor chamber. The most outstanding feature of this new system is that the use of a faster monochromator ($\text{f}\text{75.3}$) and a cylindrical lens theoretically increases light intensity by up to 100 times that of the commercial scanner, under otherwise identical conditions. Other advantages include the following: (1) For collecting and collimating light, two pairs of mirrors give a precell optical system focused in the radial direction at all wavelengths of light; (2) these components and the lamp are located on a table outside the centrifuge, so virtually any size of lamp can be used; (3) the entire precell optical system is a self-contained unit which, within reasonable limits, may be moved to any desired location without markedly affecting the quality of the collimated light; and (4) the optical path length has been shortened, providing less dissipation of light energy. The principles behind the selection and design of the key components are discussed. New alignment procedures and apparatus developed to aid in fast, easy, accurate alignment are described and discussed. Several components for use with a system using a computer-controlled stepping motor scanner for collection of data are also described. This system is simple enough and is documented in sufficient detail so that other interested workers, even those with little or no optics experience, can duplicate and use the system.     

Epoxidation of unsaturated fatty esters in argentation chromatography.

Absorption chromatography of unsaturated esters on silver ion-silica gel columns leads to the formation of epoxides, if solvents containing peroxides are used. With small samples of radioactive esters the epoxide is formed in proportion so large that subsequent analytical procedures will reveal the epoxide, to the possible confusion of the investigator. Data on the behavior of epoxides of common unsaturated fatty esters in TLC and GLC are presented.     

The staining pattern of collagen fibrils. Improved correlation with sequence data.

The periodic banding pattern of stained collagen fibrils observed in the electron microscopic can be correlated with the charge distribution deduced from the amino acid sequence. Earlier work used alpha 1 chain sequence data only. The present study incorporates alpha 2 as well as alpha 1 sequence data, so that the complete distribution of charged residues is used. Correlation is improved if it is supposed that the extrahelical terminal regions are contracted. The optimal value of the periodicity, D, (previously 232.3 +/- 0.5 residues using alpha 1 data only), is now 234.2 +/- 0.5 residues, assuming uniform spacing of residues in the helical body of the molecule. This value agrees better with values obtained by others from analyses of interactions between molecules, using sequence data alone. Using the improved value of D, the relative axial locations of the charged residues in the fibril are displayed. In this way, the charged residues contributing to each band in the fibril staining pattern can be identified.     

The chemical restraint of apes and monkeys by means of phencyclidine or ketamine.

The anesthetic effects of two drugs, namely, Phencyclidine and Ketamine, used alone or in combination with atropine, were compared during clinical and experimental procedures on different primate species ranging from gorillas, orangutans, white-faced and dwarf chimpanzees, baboons, cercopithecus monkeys to new--world monkeys. It is concluded that both these anesthetics are very good and safe drugs for restraint and anesthesia. Ketamine appeared to be superior to Phencyclidine for use among apes and monkeys in so far as it is shorter acting, has wider safety margin and shorter recovery time, provides better muscle relaxation and is practically without side effects. But Phencyclidine has definite advantage in so far as it is needed is smaller quantity to produce comparable effect of anesthesia.     

Reciprocal role of the inward currents ib, Na and i(f) in controlling and stabilizing pacemaker frequency of rabbit sino-atrial node cells.

Experiments and computations were done to clarify the role of the various inward currents in generating and modulating pacemaker frequency. Ionic currents in rabbit single isolated sino-atrial (SA) node cells were measured using the nystatin-permeabilized patch-clamp technique. The results were used to refine the Noble-DiFrancesco-Denyer model of spontaneous pacemaker activity of the SA node. This model was then used to show that the pacemaker frequency is relatively insensitive to the magnitude of the sodium-dependent inward background current ib, Na. This is because reducing ib, Na hyperpolarizes the cell and so activates more hyperpolarizing-activated current, i(f), whereas the converse occurs when ib, Na is increased. The result is that i(f) and ib, Na replace one another and so stabilize nodal pacemaker frequency.     

Subunit interaction during catalysis. Alternating site cooperativity of mitochondrial adenosine triphosphatase.

ATP concentration modulates oxygen exchange catalyzed by purified, soluble mitochondrial ATPase during ATP hydrolysis so that water oxygen incorporation into each Pi formed increases markedly as ATP concentration is lowered. This behavior is readily explained by catalytic cooperativity between subunits of the ATPase. However, other reasonable explanations also need consideration. A new approach for assessing these various explanations is used, based on measurement of the [18O]Pi species formed by hydrolysis of ATP highly labeled with 18O in the gamma-phosphoryl group. The results and other supporting data give what appears to be the most compelling evidence yet attained for alternating site catalytic cooperativity in an enzymic catalysis.     

Macromolecular diffusion in crowded solutions.

The effects of crowding on the self or tracer diffusion of macromolecules in concentrated solutions is an important but difficult problem, for which, so far, there has been no rigorous treatment. Muramatsu and Minton suggested a simple model to calculate the diffusion coefficient of a hard sphere among other hard spheres. In this treatment, scaled particle theory is used to evaluate the probability that the target volume for a step in a random walk is free of any macromolecules. We have improved this approach by using a more appropriate target volume which also allows the calculation to be extended to the diffusion of a hard sphere among hard spherocylinders. We conclude that, to the extent that proteins can be approximated as hard particles, the hindrance of globular proteins by other proteins is reduced when the background proteins aggregate (the more so the greater the decrease in particle surface area), the hindrance due to rod-shaped background particles is reduced slightly if the rod-like particles are aligned, and the anisotropy of the diffusion of soluble proteins among cytoskeletal proteins will normally be small.     

Robusta-Natalensis Pair. Sp. 30. C. Robusta. Sp.31. C. Natalensis.

T he two giants of the genus-that is so far as the cock birds are concerned, but, as with chiniana and a few others, their hens are so much smaller that even when in the field the two sexes are seen in company one may often doubt their being a pair of the same species.     

Analytical scanning isoelectrofocusing. 5. Separation of glycinin subunits in urea-dithiothreitol media

As exemplified by glycinin, a method has been developer for the isoelectrofocusing of protein subunits in sucrose density gradients containing urea and dithiothreitol. Only microgram quantities of proteins need to be used. The technique involves direct optical scanning of micro quartz tubes in a vertical device utilizing the linear transport system of the Gilford spectrophotometer. The current is not interrupted during focusing so that kinetic tracings of the separated zones can be obtained at desirable time intervals and selective wavelength. By the use of dissociating media, observed microheterogeneity can be attributed mainly to differences in the primary structure of the subunits.     

Centralised interpretation of electrocardiograms.

A system was devised so that a peripheral hospital could transmit electrocardiograms (ECGs) to a central computer for interpretation. The link that transmits both ECGs and reports is provided by the telephone network. Initial results showed that telephone transmission did not significantly affect the accuracy of the ECG interpretation. The centralised computer programme could be much more widely used to provide ECG interpretations. A telephone link would not be justified in health centres, where the demand for ECGs is fairly small, but ECGs recorded at a health centre can be sent to the computer for interpretation and returned the next day. The most cost-effective method of providing computer interpretation for several health centres in a large city would be to have a portable electrocardiograph and transmission facilities, which could be moved from centre to centre.     

森林叶凋落物混合分解的研究I.缩微(Microcosm)实验

采用缩微实验法 ,初步系统研究了杉木叶凋落物分别与火力楠、红栲和木荷 3个阔叶树种之一的叶凋落物两两混合分解的动态变化 ,以探明凋落物混合分解过程中可能存在的相互作用 .结果表明 ,杉木叶凋落物与 3种阔叶树种叶凋落物两两混合分解时所表现出不同的相互作用形式 :杉木与木荷表现出抑制作用 ,杉木与红栲或火力楠表现为较弱的促进作用 .     

Cultivation of Oudemansiella tanzanica nom. prov. on agricultural solid wastes in Tanzania

The edible mushroom Oudemansiella tanzanica nom. prov., which is new to science, has been studied as a potential crop to reduce agricultural solid wastes and increase domestic mushroom production. The substrates sawdust, sisal waste and paddy straw supplemented with chicken manure resulted in the highest biological efficiencies of any mushroom cultivated in Tanzania so far. In addition, the mushroom has one of the shortest cultivation cycles at 24 d. Despite the fact that the mushroom extracts substantial amounts of nutrients, the spent substrate can be used as fodder, as a soil conditioner and fertilizer and in bioremediation.     

Activation of C55-isoprenoid alcohol phosphokinase from Staphylococcus aureus. II. Biophysical studies.

Physicochemical techniques were used to investigate the activation of C55-isoprenoid alcohol phosphokinase by synthetic lecithins. Complexes of the enzyme with phospholipids were prepared using a method employing sodium dodecyl sulfate as a protein-solubilizing agent. Circular dichorism and the intrinsic fluorescence of the kinase were used as optical probes of protein conformation with these complexes. No evidence for a major lipid-dependent conformational change in the protein was observed when these complexes were studied under conditions where the lipid mesomorphic transitions occurred. EPR studies of mixtures of synthetic lecithins and the C55-isoprenoid alcohol indicated a correlation between kinase activity and the rotational diffusion rate within the hydrophobic phase. It is concluded that the lipid physical state probably does not affect the enzyme activity by altering the protein conformation but more likely does so by affecting the motion of the molecular participants in the reaction.     

pH oscillations in transport process.

The paper discusses in more detail four published crystal structures which were used (McGavin, 1971a) in supporting the idea that base pairs in nucleic acid structures might be able to pair with identical base pairs about dyad axes so that specific four-strand structures are formed. The improbability of pairing unlike base pairs in such structures is discussed in more detail. Specific four-strand models themselves are also briefly discussed.     

Automated isocratic high-performance liquid chromatography of inositol phosphate isomers.

Isomers of inositol phosphates from biological samples can be analysed by anion-exchange h.p.l.c., by using isocratic elution with phosphate buffers. The method involves the preliminary processing of the extracted samples with conventional soft-gel anion-exchange resins, including the commonly used Dowex resins, followed by direct analysis with h.p.l.c. of a portion of relevant fractions. Run times (up to 20 min) and collected fraction numbers (up to 24) are minimal, so that if the method is used in conjunction with automated h.p.l.c. injection a high throughput of samples is achieved.