bluuebunny/crossref_metadata_2025_split huggingface dataset:
Depolarization‐Induced Increase in Surface Binding and Internalization of 125I‐Nerve Growth Factor by PC 12 Pheochromocytoma Cells
Authors: Koike Tatsuro 
Published: October 2006

AbstractThe binding and internalization of 125I‐nerve growth factor (NGF) by PC 12 pheochromocytoma cells was studied as a function of extracellular potassium concentration. Both surface‐bound and internalized fractions of 125I‐NGF associated with the cells under depolarizing conditions (50 mM K+) increased to 144 ± 28% (average ± SEM, six different cell preparations) and to 176 ± 12% (n = 6), respectively, of those observed at 6.0 mM K+. Scat‐chard‐type analysis of the data indicates increased sites for the binding and internalization of iodinated NGF by the cells. Similar enhancement was observed for cells treated with NGF as well. This voltage‐dependent phenomenon was reversible, and also observed in the presence of veratri‐dine. Moreover, withdrawal of extracellular Ca2+ abolished high K+‐induced modulation of 125I‐NGF binding and internalization, indicating that this effect may be mediated by Ca2+.
Ontogeny of Glucose and Lipid Metabolism in Dorsal Root Ganglia of Chickens.: Similarities and Contrasts with Sympathetic Ganglia
Authors: Larrabee Martin G. 
Published: October 2006

AbstractDorsal root ganglia, excised from the lumbar roots of the sciatic nerve of white Leghorn chicken embryos 6–13 days of age, were incubated usually for 5 h, at 36°C in 20 μI of a bicarbonate‐buffered physiological salt solution containing 5.5 mM glucose. [U‐14C]Glucose, [1‐14C]glucose, [6‐14C]glucose, or [5‐3H]uridine was also added. Lipid synthesis and lactate output were measured by incorporation of 14C from [U‐14C]glucose and RNA synthesis by incorporation of 3H from [5‐3H]uridine. Glucose uptake and labeled lactate output declined rapidly from 6 to 8–9 days of age, more slowly thereafter. Synthesis of lipids was relatively constant throughout the ages studied, without the increased rate at intermediate ages seen previously in sympathetic ganglia of the same species. RNA synthesis declined progressively throughout the ages studied. The output of C‐6 of glucose to CO2 was about the same at all ages, whereas that of C‐1 declined rapidly from 6 to 7 days of age and then more slowly, but always remained higher than that of C‐6 and thus indicated that much glucose was metabolized via the hexosemonophosphate shunt.
Amino Acid Sequences of Neuropeptides in the Sinus Gland of the Land Crab Cardisoma carnifex: A Novel Neuropeptide Proteolysis Site
Authors: Newcomb Robert W. 
Published: October 2006

AbstractThe sinus gland is a major neurosecretory structure in Crustacea. Five peptides, labeled C, D, E, F, and I, isolated from the sinus gland of the land crab have been hypothesized to arise from the incomplete proteolysis at two internal sites on a single biosynthetic intermediate peptide “H,” based on amino acid composition additivities and pulse‐chase radiolabeling studies. The presence of only a single major precursor for the sinus gland peptides implies that peptide H may be synthesized on a common precursor with crustacean hyperglycemic hormone forms, “J” and “L,” and a peptide, “K,” similar to peptides with molt inhibiting activity. Here I report the amino acid sequences of these peptides. The amino terminal sequence of the parent peptide, H, (and the homologous fragments) proved refractory to Edman degradation. Data from amino acid analysis and carboxypeptidase digestion of the naturally occurring fragments and of fragments produced by endopeptidase digestion were used together with Edman degradation to obtain the sequences. Amino acid analysis of fragments of the naturally occurring “overlap” peptides (those produced by internal cleavage at one site on H) was used to obtain the sequences across the cleavage sites. The amino acid sequence of the land crab peptide H is Arg‐Ser‐Ala‐Asp‐Gly‐Phe‐Gly‐Arg‐Met‐Glu‐Ser‐Leu‐Leu‐Thr‐Ser‐Leu‐Arg‐Gly‐Ser‐Ala‐Glu‐Ser‐Pro‐Ala‐Ala‐Leu‐Gly‐Glu‐Ala‐Ser‐Ala‐Ala‐His‐Pro‐Leu‐Glu. In vivo cleavage at one site involves excision of arginine from the sequence Leu‐Arg‐Gly, whereas cleavage at the other site involves excision of serine from the sequence Glu‐Ser‐Leu. Proteolysis at the latter sequence has not been previously reported in intact secretory granules. The aspartate at position 4 is possibly covalently modified.
Solubilization and Characterization of Calcitonin Gene‐Related Peptide Binding Site from Porcine Spinal Cord
Authors: Hiroshima Osamu , Sano Yoshihisa , Yuzuriha Teruaki , Yamato Chiyuki , Saito Akira , Okamura Naomichi , Uchiyama Yasuo , Kimura Sadao , Goto Katsutoshi 
Published: October 2006

AbstractThe binding site for calcitonin gene‐related peptide (CGRP) was solubilized with 3‐[(3‐cholamidopropyl) dimethylammonio]‐1‐propane sulfonate (CHAPS) in an active form from porcine spinal cord. l25I‐labeled human α‐CGRP (125I‐CGRP) binding to the solubilized protein was determined by filration using a GF/B glass filter. The maximal binding activity (˜60% of the crude membrane fraction) was obtained with 5 mM CHAPS. 125I‐CGRP binding to the solubilized protein was of high affinity, saturability, and high specificity, having KD and Bmax values of 3.69 pM and 338 fmol/mg of protein, respectively. The binding activity was eluted in a single peak with a molecular mass of 400,000 daltons by gel filtration on TSK gel G4000SW. These results suggest that the solubilized protein may be responsible for the specific binding site.
Large‐Scale, One‐Step Purification of Oxidized and Reduced Forms of Bovine Brain S100b Protein by HPLC
Authors: Mely Y. , Gérard D. 
Published: October 2006

AbstractA rapid and simple method, using a reverse‐phase column in a HPLC system, has been developed to purify high yields of both oxidized and reduced S100b proteins from a bovine brain S100 protein mixture. The final proteins were characterized by amino acid analysis, sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, and ab‐sorbance and fluorescence spectroscopy. Both S100b subtypes appeared highly purified and differed only by their oxidation state: all four cysteinyl sulfhydryl groups were free in reduced S100b protein whereas two of them gave disulfide bridges in oxidized S100b protein. The stability of the oxidation state of the two isolated subtypes suggests that the two forms were not in rapid equilibrium and probably coexisted in vivo.
Effects of Protonophores on the Synthesis of Catecholamines and the Intracellular pH in Cultured Bovine Adrenal Medullary Cells
Authors: Yokota Kenji , Yanagihara Nobuyuki , Izumi Futoshi , Wada Akihiko 
Published: October 2006

AbstractThe protonophores carbonyl cyanide p‐trifluoromethoxyphenylhydrazone (FCCP) and carbonyl cyanide m‐chlorophenylhydrazone (CCCP) stimulated the synthesis of 14C‐catecholamines from [14C]tyrosine in cultured bovine adrenal medullary cells. The stimulatory effect of CCCP but not of FCCP was partially dependent on extracellular Ca2+. CCCP but not FCCP increased the influx of 45Ca2+ to the cells. When cells were incubated with either CCCP or FCCP (0.01–0.2 μg/ml), the intracellular pH fell from 7.2 to 6.3–6.5 and catecholamine synthesis increased. Tyrosine hydroxylase activity in a soluble fraction prepared from cultured adrenal medullary cells was measured after incubation of the cells with FCCP or CCCP. Although FCCP did not affect the activity of the enzyme, CCCP caused a stable activation of it which was dependent on extracellular Ca2+. Since the optimal pH of soluble tyrosine hydroxylase is around 6.0 in adrenal medullary cells, FCCP may increase the synthesis of catecholamines by shifting the intracellular pH toward it. In addition to this mechanism, CCCP may enhance the synthesis of catecholamines by a Ca2+‐dependent mechanism.
Developmental Expression of the P0 Glycoprotein and Basic Protein mRNAs in Normal and Trembler Mutant Mice
Authors: Garbay Bertrand , Domec Christine , Fournier Michel , Bonnet Jacques 
Published: October 2006

AbstractMice affected by the autosomal dominant Trembler mutation exhibit a severe hypomyelinization of the PNS. Previous biochemical studies have shown that the accumulation of the major PNS myelin proteins, P0 and myelin basic protein (MBP), is strongly diminished in Trembler sciatic nerves during postnatal development. We performed Northern blots which showed that the size of mRNA species for P0 and MBP in normal and mutant mice are indistinguishable. Densitometric analysis of Northern blots showed that, in normal mice, the proportion of P0 mRNA increases up to the 12th day, then decreases slowly. At day 40, the proportion is 60% of the maximal value. In the mutant, the proportion of P0 mRNA increases up to the 12th day and then decreases much faster than in the control. At days 12 and 40, the P0 mRNA proportion measured in Trembler sciatic nerves rep resents only 40% and 7%, respectively, of the proportion measured in control littermates. The MBP mRNA proportion in the normal mice increases up to the 16th day, and then decreases to attain 45% of the maximum level at day 40. In the Trembler mouse, there is a maximum level at day 12, representing 25% of the normal level, but the MBP mRNA is barely detectable at days 8 or 40. Thus, these data seem to indicate that in the Trembler sciatic nerves, the proportions of P0 and MBP mRNAs are too small to allow the synthesis of normal levels of the corresponding proteins.
Investigations on the Incorporation of a Tritiated Ganglioside, GM1, in the Injured and Intact Sciatic Nerves of the Rat
Authors: Lang W. , Stotzem C. D. 
Published: October 2006

AbstractFollowing injury of their left sciatic nerves by means of a standardized procedure, male rats received intravenous injections of a tritiated ganglioside, GM1, on different days during the process of regeneration. The rats were killed at two different times after the injection and the concentrations of the total radioactivity, nonvolatile radioactivity, and labelled GM1 were estimated in six segments of the crushed and intact sciatic nerves. The segments of the damaged nerves showed higher concentrations of radioactivity and a higher content of GM1 than the corresponding segments of the contralateral nerves. Within the immediate area of the lesion the highest levels were found on the 3rd and 6th days after the injury; the segments distal from the lesion showed the highest levels of activity on days 9 and 12. The nerve segments proximal to the site of the injury showed a low rate of radioactivity incorporation. The higher concentrations of [3H]GM1 in damaged nerves as well as the rate of incorporation as a function of time indicate that exogenous gangliosides may be involved in the processes of regeneration and have a bearing on the latter.
γ‐Aminobutyric AcidB Receptor Activation Modifies Agonist Binding to β‐Adrenergic Receptors in Rat Brain Cerebral Cortex
Authors: Scherer Roberta W. , Ferkany John W. , Karbon E. William , Enna S. J. 
Published: October 2006

AbstractThe interaction of isoproterenol with β‐adrenergic receptor (βAR) binding sites was measured in membranes prepared from rat brain cerebral cortical slices previously incubated in the presence or absence of γ‐aminobutyric acid (GABA) receptor agonists. Both GABA and baclofen, but not isoguvacine, altered βAR agonist binding by increasing the affinity of both the low‐ and high‐affinity binding sites and by increasing the proportion of low‐affinity receptors. The response to baclofen was stereoselective, and the effect of GABA was not inhibited by bicuculline. The results suggest that GABAB, but not GABAA, receptor activation modifies the coupling between βAR and stimulatory guanine nucleotide‐binding protein, which may in part explain the ability of baclofen to augment isoproterenol‐stim‐ulated cyclic AMP accumulation in brain slices.
Postnatal Development of a Granule Cell‐Enriched, Neurone‐Specific Glycoprotein, gp50, in Normal and Thyroid‐Deficient Rats
Authors: Beesley Philip W. , Paladino Toni , Hill Irene , Gravel Claude , Hawkes Richard B. , Gurd James W. 
Published: October 2006

Abstract:Glycoprotein gp50 is a neurone‐specific, granule cell‐enriched glycoprotein that is also a major component of isolated synaptic membranes. Here, we describe the use of a monoclonal antibody, mab SM gp50, to study the postnatal development of gp50 in the brain of normal and thyroiddeficient rats. Radioimmunoassay, enzyme‐linked immunosorbent assay, and Western blotting show that gp50 is not detectable in brain until postnatal day 4 (P4) in both forebrain and cerebellum. In forebrain, the rate of increase of gp50 levels is maximal between P12 and P20. It is somewhat later in cerebellum, where peak levels are attained between P30 and P35. Immunocytochemical studies show little detectable gp50‐like immunoreactivity before P16, and the staining is still weak, relative to adult tissue, at P25. The intense staining of the granule cell layer characteristic of adult cerebellum predominantly appears after P25. Development of gp50 is severely retarded in the cerebellum of thyroid‐deficient rats, particularly during the second and third postnatal weeks. However, by the fourth postnatal week, gp50 levels in normal and hypothyroid animals are comparable. The results indicate that significant alterations in the pattern of gp50 expression continue to occur at a late stage of cerebellar development. In particular, the increase in immunocytochemical staining of the granule cells after P25 is striking in that by this time most major events associated with cerebellar development are essentially complete.
Food for the Future
Authors: Harrar J. G. 
Published: October 2006

There is ample justification for concern about adequate food supplies for future generations of mankind, but this concern should be broadened to include the immediate problem of an adequate standard of living for the world's present population. The successful solution of the immediate problems would furnish the best background of experience for meeting those that will arise in the future. First steps include the acceptance by society of responsibilities for the extension of the benefits of education throughout the world and provision for the type of scientific, economic, social, political, and religious leadership necessary to assure food for all on a continuing basis.
Striking improvements in the food supply can be readily made through the application of present knowledge, if the foregoing conditions are met. The rapid pace of modern science, both pure and applied, gives promise that future benefits may be much greater than those thus far experienced. Current advances do not signal the end of a technical road but rather that the great scientific developments still lie ahead. If we have the intelligence and wisdom to recognize human responsibilities and to make constructive use of our natural and human resources, we can look forward to a better world in the future and improved standards of living for all.
On the Mitotic Movements of Chromosomes
Authors: Carlson J. Gordon 
Published: October 2006

My conclusions, which, I confess, are tentative and based mainly on studies of one kind of cell, the grasshopper neuroblast, may be summarized as follows.
The late prophase orientation of the chromosomes is a carry-over from the late telophase orientation. It is apparently maintained by means of the centromeres, which appear to be attached within a limited region of the nucleus throughout telophase, interphase, and prophase.
Metaphase orientation of the chromosomes may be explained as the resultant of two forces: a force involving the centromere and spindle, which is responsible for keeping the centromeres in the equatorial plane of the spindle, and a repulsion force involving the noncentromeric portion of the chromosomes, which results in a tendency toward uniform spacing of the chromosomes outside the spindle.
Anaphase separation of sister chromatids and their subsequent movement toward the poles of the spindle involves at least four distinct phases: (i) the initial poleward movement of the centromeres, which may be due to intrinsic repulsion or to a force acting between spindle and centromeres that produces an angle of almost 90 degrees between the separated and unseparated portions of the chromatids; (ii) the autonomous separation of the noncentromeric part of the chromosome; (iii) elongation of the spindle, beginning just after the sister chromatids are separated proximally and ending when the longer chromatids are about to lose contact distally; and (iv) the later movement apart of the daughter chromosomes, probably resulting from a pushing force exerted by elongation of the interzonal fibers.
Basic Research in Europe
Authors: Gates David M. 
Published: October 2006

Europe, traditionally the breeding ground for basic scientific research until the 1930's, is only now approaching full recovery from the devastating effects of the war. Great Britain has a more stimulating climate for research, a more progressive graduate-school program, and a more flexible professorship structure than any other country of Europe. Germany still has several years to go before the effects of the war will be obliterated. In most northern European countries, the organization and support of academic research ranges from good to excellent, and a stimulating intellectual atmosphere exists. Germany is rapidly contending for the lead in basic research along with England and Sweden, which are now in the forefront. The Netherlands is typified by superb organization, and most of the Scandinavian countries are high in quality if not always in quantity of research. France is characterized by brilliant individual contributions but over-all falls far short of her potential for scientific research. Switzerland, a highly industrialized country, is geared primarily for engineering and does not compete as highly on basic research as might otherwise be expected. Italian research is good in certain areas but is plagued by a number of difficulties that retard progress. Nevertheless, there are encouraging efforts being made in Italy to develop some good scientific programs. In the south of Europe the situation is generally discouraging and will continue to be so, except where a few dedicated, brilliant individuals are making good contributions with the meager resources available.
Europe will continue to be a tremendous scientific manpower reserve for the United States, and, despite accusations of proselyting, the fact remains that in many European countries the employment possibilities are not commensurate with the production rate of scientists and engineers. If the universities of Europe would realign the professional structure of their departmental staffs and extend their graduate curricula they would give far more opportunity to young research scientists and make better use of their facilities. America can indeed be grateful to Europe for a great cultural and academic heritage, and one can sincerely hope that close cooperation in science will take place for many years to come.
Of Time and the Moon
Authors: Wetherill George W. 
Published: October 2006

Considerable information concerning lunar chronology has been obtained by the study of rocks and soil returned by the Apollo 11 and Apollo 12 missions. It has been shown that at the time the moon, earth, and solar system were formed, ∼4.6 × 10
9
years ago, a severe chemical fractionation took place, resulting in depletion of relatively volatile elements such as Rb and Pb from the sources of the lunar rocks studied. It is very likely that much of this material was lost to interplanetary space, although some of the loss may be associated with internal chemical differentiation of the moon.

It has also been shown that igneous processes have enriched some regions of the moon in lithophile elements such as Rb, U, and Ba, very early in lunar history, within 100 million years of its formation. Subsequent igneous and metamorphic activity occurred over a long period of time; mare volcanism of the Apollo 11 and Apollo 12 sites occurred at distinctly different times, 3.6 ×10
9
and 3.3 × 10
9
years ago, respectively. Consequently, lunar magmatism and remanent magnetism cannot be explained in terms of a unique event, such as a close approach to the earth at a time of lunar capture. It is likely that these phenomena will require explanation in terms of internal lunar processes, operative to a considerable depth in the moon, over a long period of time. These data, together with the low present internal temperatures of the moon, inferred from measurements of lunar electrical conductivity, impose severe constraints on acceptable thermal histories of the moon.

Progress is being made toward understanding lunar surface properties by use of the effects of particle bombardment of the lunar surface (solar wind, solar flare particles, galactic cosmic rays). It has been shown that the rate of micrometeorite erosion is very low (angstroms per year) and that lunar rocks and soil have been within approximately a meter of the lunar surface for hundreds of millions of years.
Future work will require sampling distinctly different regions of the moon in order to provide data concerning other important lunar events, such as the time of formation of the highland regions and of the mare basins, and of the extent to which lunar volcanism has persisted subsequent to the first third of lunar history. This work will require a sufficient number of Apollo landings, and any further cancellation of Apollo missions will jeopardize this unique opportunity to study the development of a planetary body from its beginning. Such a study is fundamental to our understanding of the earth and other planets.
Restored Pictures of Ganymede, Moon of Jupiter
Authors: Frieden B. Roy , Swindell William 
Published: October 2006

Restored pictures of Ganymede have been produced that have some identifiably reliable features and some identifiable artifacts. The latter arise from artifacts in parts of the red image data. Among the presumably reliable features are some mare-like objects (perhaps with some internal structure), and a few rather large, bright rings. Whether the latter are ice, or arise from near-specular reflection from smooth surface features, is left for future investigation.
One of the restoring methods used, maximum entropy, has been shown to be applicable to moderately extended images. In view of its short time requirements (30 seconds per picture), the method should be applicable to moderately larger images, for example with twice the given number of data points.
A common genetic variant in XPD associates with risk of 5q- and 7q-deleted acute myeloid leukemia
Authors: Smith Alexandra G. , Worrillow Lisa J. , Allan James M. 
Published: October 2006

Abstract
Numerous structural genetic abnormalities observed in acute myeloid leukemia (AML) illustrate the heterogeneity of this disease, which likely has contributed to difficulty in identifying susceptibility alleles for AML. We previously reported that carriers of the glutamine-encoding allele at codon 751 of the xeroderma pigmentosum group D (XPD) DNA repair gene were significantly more likely to have a karyotype associated with a less favorable prognosis, and hypothesized that this observation was driven by an association between the codon 751 variant and risk of developing AML with specific structural abnormalities. Using a case series of 927 patients with AML, we show here that the XPD codon 751 glutamine-encoding variant significantly associates with risk of developing AML with a chromosome 5q deletion (odds ratio [OR] 2.09; 95% confidence interval [CI] 1.14-3.81; n = 69; P = .02) or a chromosome 7q deletion (OR 2.27; 95% CI 1.09-4.71; n = 47; P = .03), but not with any other commonly recurring cytogenetic lesion.