bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thiamin Deficiency in the Lamb: Changes in Thiamin Phosphate Esters in the Brain
Authors: Thornber E. J. , Dunlop R. H. , Gawthorne J. M. 
Published: October 2006

Abstract: Concentrations of thiamin (unphosphorylated), thiamin monophosphate (TMP), thiamin diphosphate (TDP), and thiamin triphosphate (TTP) were measured in three regions of the brain of seven pairs of lambs. The lambs were maintained on a thiamin‐free synthetic diet for 2, 3, or 4 weeks. Controls were pair‐fed and supplemented with thiamin. The three brain regions were: (1) dorso‐lateral aspect of the cortex [common site for lesions of polioencephalomalacia (PEM)]; (2) pyriform lobe of the cortex (no PEM lesions are found here); (3) white matter of the internal capsule (no PEM lesions found here). The concentration of TTP in all three sections of brain was maintained at control values for up to 4 weeks on the thiamin‐deficient diet. TDP concentration decreased to 22% of control values in both regions of grey matter after 4 weeks on the diet. Unphosphorylated thiamin and TMP decreased to a smaller extent than TDP.
A New Class of Monoamine Oxidase Inhibitors
Authors: Vunnam R. R. , Bond D. , Schatz R. A. , Radin N. S. , Narasimhachari N. 
Published: October 2006

Abstract:Newly synthesized compounds have been found to inhibit mitochondrial monoamine oxidase (MAO) in mouse brain and rat liver. A series of 2‐acylamino‐3‐tert‐aminopropiophenones acted preferentially against MAO type B (2‐phenylethylamine as substrate), apparently irreversibly. 2‐Decanoylamino‐3‐morpholinopropiophenone acted similarly in vivo toward the cerebral MAO, producing a dose‐related inhibition. At high dose levels, MAO type A was also severely inhibited. The effects were produced rapidly and restoration of enzyme activity also appeared rapidly. The half‐life for MAO type A could be estimated from the rate of enzyme reappearance to be 13 h. It is suggested that the amino ketones undergo a β‐elimination reaction at the enzyme's active site, forming a reactive species (an α,β‐unsaturated ketone), which reacts covalently with a nucleophilic group of the enzyme by a Michael addition. Some other related compounds, derivatives of phenylpropane, also showed inhibitory activity against MAO, particularly against type A (serotonin as substrate). The morpholino compound might have promise as a quickly effective, short‐acting inhibitor of MAO type B.
Inhibition of Synaptosomal Neurotransmitter Uptake by Hallucinogens
Authors: Whipple Michael R. , Reinecke Manfred G. , Gage Fred H. 
Published: October 2006

Abstract:The effect of 13 hallucinogens on the uptake of serotonin and norepinephrine into hippocampal synaptosomes and of serotonin and dopamine into caudate synaptosomes was found to be inhibitory, except for lysergic acid diethylamide and 2‐bromolysergic acid diethylamide, which were inactive. The indoleal‐kylamines were generally more potent than the phenylethylamines. The reported inhibition of uptake of serotonin by 5‐methoxy‐N,N‐dimethyltryptamine and lysergic acid diethylamide into whole brain synaptosomes was not reproducible at concentrations 102 to 104 times higher than those stated in the literature.
[3H]8‐Hydroxy‐2‐(Di‐n‐Propylamino)Tetralin Binding to Pre‐ and Postsynaptic 5‐Hydroxytryptamine Sites in Various Regions of the Rat Brain
Authors: Hall M. D. , Mestikawy S. El , Emerit M. B. , Pichat L. , Hamon M. , Gozlan H. 
Published: October 2006

Abstract:The specific binding of [3H]8‐hydroxy‐2‐(di‐n‐propylamino)tetralin ([3H]8‐OH‐DPAT) to 5‐hydroxytryptamine (5‐HT)‐related sites was investigated in several regions of the rat brain. Marked differences were observed in the characteristics of binding to membranes from hippocampus, striatum, and cerebral cortex. Hippocampal sites exhibited the highest affinity (KD > 2 nM) followed by the cerebral cortex (KD > 6 nM) and the striatum (KD > 10 nM). Ascorbic acid inhibited specific [3H]8‐OH‐DPAT binding in all three regions but millimolar concentrations of Ca2+, Mg2+, and Mn2+ enhanced specific binding to hippocampal membranes, whereas only Mn2+ increased it in the cerebral cortex and all three cations inhibited specific binding to striatal membranes. Guanine nucleotides (0.1 mM GDP, GTP) inhibited binding to hippocampal and cortical membranes only. As intracerebral 5,7‐dihydroxytryptamine markedly decreased [3H]8‐OH‐DPAT binding sites in the striatum, but not in the hippocampus, the striatal sites appear to be on serotoninergic afferent fibers. In contrast, in the hippocampus the sites appear to be on postsynaptic 5‐HT target cells, as local injection of kainic acid decreased their density. Both types of sites appear to be present in the cerebral cortex. The postsynaptic hippocampal [3H]8‐OH‐DPAT binding sites are probably identical to the 5‐HT1A, subsites, but the relationship between the presynaptic binding sites and the presynaptic autoreceptors controlling 5‐HT release deserves further investigation.
Pyruvate Dehydrogenase Activity in Osmotically Shocked Rat Brain Mitochondria: Stimulation by Oxaloacetate
Authors: Haas Richard H. , Thompson Geoffrey , Morris Bernard , Conright Kelly , Andrews Torre 
Published: October 2006

AbstractPyruvate dehydrogenase complex activity (PDHC) measured by CO2 release isotopic assay has generally been much lower than activity measured by the spec‐trophotometric arylamine acetyltransferase assay (ArAT). Decarboxylation of [l‐14C]pyruvate was measured in osmotically shocked rat brain cortical mitochondria. Activity is dependent on the concentration of the substrate pyruvate. Activity of 74.6 units ± 12.3 SD (n = 22) was observed at 4 mM pyruvate (1 unit = 1 nmol pyruvate decarboxy‐lated/min/mg protein). Activity was dependent on added NAD, CoA, and thiamine pyrophosphate, implying increased mitochondrial permeability after osmotic shock. Freeze/thaw with sonication of the mitochondrial preparation reduced PDHC activity to 11.5 units ± 3.0 SD (n = 4). Oxaloacetate produced a marked stimulation of activity. The optimal assay contained 3 mM oxaloacetate, and without oxaloacetate activity fell to 15.4 units ± 9.9 SD (n = 8). These studies highlight the importance of optimal substrate concentrations in the CO2 release isotopic PDHC method. Higher PDHC activity is found with intact mitochondria and thus activity values should be interpreted in the light of the presence or absence of intact mitochondria in individual preparations.
Kinetic Characterization of Inhibition of γ‐Aminobutyric Acid Uptake into Cultured Neurons and Astrocytes by 4,4‐Diphenyl‐3‐Butenyl Derivatives of Nipecotic Acid and Guvacine
Authors: Larsson O. M. , Falch E. , Krogsgaard‐Larsen P. , Schousboe A. 
Published: October 2006

AbstractThe effects of N‐(4,4‐diphenyl‐3‐butenyl) derivatives of nipecotic acid (SKF‐89976‐A and SKF‐100844‐A) and guvacine (SKF‐100330‐A) on neuronal and astroglial γ‐aminobutyric acid (GABA) uptake were investigated. In addition, the uptake of SKF‐89976‐A was studied using the tritiated compound. All of the compounds were found to be competitive inhibitors of GABA uptake irrespective of the cell type, with Ki values similar to or lower than those of the parent amino acids. Moreover, none of the compounds exhibited selectivity with regard to inhibition of neuronal and glial GABA uptake. In spite of the competitive nature of SKF‐89976‐A, the compound was not transported by the GABA carriers in the two cell types, because no saturable uptake could be demonstrated.
Phorbol Ester‐Induced Upregulation of Angiotensin II Receptors in Neuronal Cultures Is Potentiated by a Calcium Ionophore
Authors: Sumners Colin , Rueth Susan M. , Myers Linda M. , Kalberg Christopher J. , Crews Fulton T. , Raizada Mohan K. 
Published: October 2006

AbstractPrevious studies have suggested that protein ki‐nase C is important in the regulation of angiotensin II receptors in neuronal cultures, because the C‐kinase agonists, phorbol esters, are able to increase the number of these receptors. In the present study, we have further investigated the role of protein kinase C in angiotensin II receptor regulation. This enzyme is calcium dependent, and so we investigated the effects of A23187, a calcium ionophore, on phorbol ester‐stimulated and basal angiotensin II receptor regulation. A23187, at concentrations that increased 45Ca2+ influx, caused a dose‐dependent potentiation of phorbol‐12‐myristate‐13‐acetate (TPA)‐stimulated upregulation of angiotensin II receptors. This potentiation by A23187 was a further increase in angiotensin II receptor number and was abolished in calcium‐free medium. In the absence of TPA, A23187 caused a decrease in angiotensin II receptor number, an effect not observed in calcium‐free medium. The results suggest at least two pathways for angiotensin II receptor regulation in neuronal cells: (a) by calcium‐dependent protein kinase C and (b) via an influx of calcium into the cell.
Expression of Glial Fibrillary Acidic Protein and Neurofilament mRNA in Gliosis Induced by Experimental Autoimmune Encephalomyelitis
Authors: Aquino Dennis A. , Shafit‐Zagardo Bridget , Brosnan Celia F. , Norton William T. 
Published: October 2006

Abstract:We have previously shown that the content of glial fibrillary acidic protein (GFAP) gradually increases in the spinal cord of Lewis rats with acute experimental autoimmune encephalomyelitis (EAE), reaching a level 1.5–2 times greater than that in controls by 35 days postimmunization (dpi). We report here that the increase in GFAP mRNA level followed a completely different time course and reached higher levels relative to controls than did that of the protein. Total RNA was isolated using a modified version of current methods using phenol/chloroform extractions to ensure optimal recovery from spinal cord. Control animals yielded 323 ± 35 μg (mean ± SD; n = 34) of total RNA/spinal cord throughout the experimental period. EAE animals contained up to three times as much total RNA during 11–14 dpi, a finding largely reflecting the infiltration of inflammatory cells. By 65 dpi, total RNA levels closely approached control values. As early as 10 dpi, increased amounts of GFAP mRNA were detected in EAE animals relative to controls. During 11–14 dpi, GFAP mRNA levels reached six‐ to eightfold greater than values in controls and then slowly declined throughout the remainder of the time course, with a fourfold increase still detected at 65 dpi. However, coinciding with the height of inflammation and clinical signs at 12 dpi, the GFAP mRNA content dropped to ∼50% of the level at 11 dpi but rose again at 13 dpi. This dip was mirrored by a similar decrease in neurofilament mRNA content, but otherwise the level of this message remained relatively constant and equal to that in controls. The changes in GFAP message content contrasted sharply with those in protein content, which increases slowly and does not reach maximal levels until after 4 weeks. Elevated levels of GFAP mRNA, protein, and immunostaining persisted through 65 dpi, >40 days after clinical signs had resolved.
Soil Microbiology as a Field Of Science
Authors: Waksman Selman A. 
Published: October 2006

It can now be definitely recognized that the soil microbiologist is in a position to make important contributions not only to our knowledge of soil processes and plant growth, but also to microbiology, especially microbial physiology, and to the utilization of microorganisms for various industrial, public health and other processes. The soil microbiologist is able to contribute in many ways to man's capacity to survive, by learning to control the activities of injurious microorganisms and by favoring the processes brought about by the beneficial organisms.
The reason why the broader concept "microbiology" rather than the narrower term "bacteriology" has been used throughout this discussion is that the soil microbiologist has often to pay as much attention to the fungi as to the bacteria, and occasionally also to the protozoa, the algae and even the nematodes and other worms, inhabiting the soil in large numbers. Only a recognition of all these lower forms of life and their many interrelationships can help to elucidate this complex and important science.
Evolution of Genome Size by DNA Doublings
Authors: Sparrow Arnold H. , Nauman Anne F. 
Published: October 2006

Logarithmic distributions of nucleic acid contents per genome of species within major phylogenetic groups of organisms tend to form several peaks. These peaks appear to represent intragroup doublings of DNA or RNA which, in the case of eukaryotes, are independent of polyploidy. This phenomenon has been termed cryptopolyploidy. There are numerical similarities in peak values for different taxonomic groups. A high degree of order is suggested when minimum values for the major phylogenetic groups are plotted against a series of theoretical doublings. These data demonstrate the apparent existence of an exponential periodicity over eight orders of magnitude, leading us to suggest an evolutionary continuity of doublings of a basic ancestral genome (of about 300 nucleotides), these doublings being independent of both chromosome number and ploidy level. This proposed continuity encompasses most major life forms and is generally concomitant with increasing evolutionary complexity, particularly in the prokaryotes and lower eukaryotes.
Our interpretation of the data presented here must currently be viewed as speculative, and we do not propose that genome doubling is the only mechanism for genome evolution. However, we feel that the evidence is sufficient to warrant serious scrutiny of our proposals. We hope that this approach to a synthesis of available data will provoke discussion and will stimulate further work toward either supporting, modifying, or disproving our hypothesis.
Color Defect and Color Theory
Authors: Graham C. H. , Hsia Yun 
Published: October 2006

It is important to find answers to two questions concerning the visual discriminations of dichromatic persons, especially deuteranopes: (i) Do such persons show a loss of sensitivity to various wavelengths of the spectrum as compared with normal subjects? (ii) What colors do they see?
A number of experiments were performed on the first question.

First, luminosity curves were determined on three groups of subjects, consisting respectively of five protanopes, six deuteranopes, and seven normal individuals. As compared with normal subjects, protanopes show a loss of luminosity in the red, whereas deuteranopes show a loss in the blue-to-green region of the spectrum (See
10
).

Second, we examined the luminosity curves of a subject whose right eye is classifiable (on the basis of color-mixture determinations) as normal and whose left eye is classifiable as dichromatic. (The hue discrimination curve for her dichromatic eye seemed comparable to the curve of the usual deuteranope except in the violet, where it manifested relatively good discrimination.) The luminosity function for this subject's dichromatic eye, determined by data on threshold and flicker, exhibits the same type of luminosity loss in the blue and green regions of the spectrum as was shown by our group of six deuteranopes.
Only unilaterally dichromatic subjects can tell us how colors seen by a dichromatic eye appear to a normal eye. In the color-blind eye, our unilaterally dichromatic subject sees wavelengths below and above her neutral ("grey") point (which occurs at 502 mμ) as, respectively, a blue equivalent to about 470 mμ and a yellow equivalent to about 570 mμ in her normal eye.
The results on (i) luminosity loss and (ii) the seeing of wavelengths above 502 mμ as yellow are considered theoretically. The seeing of yellow by deuteranopes and protanopes may be accounted for by an idea based on Leber-Fick transmation theory. It is proposed that the characteristic sensitivities of the red and green receptors become similar while no change takes place in their central brain connections. Losses may be introduced into the transformed sensitivity curves to indicate appropriate degrees of luminosity deficit for deuteranopes and protanopes.
Organization of Scientific Activities in Norway
Authors: Major Robert 
Published: October 2006

By way of a summary, may I say that I believe we now have in Norway an over-all pattern for the administration of research which fits our present situation reasonably well. There are weaknesses, as I have pointed out, but there are also signs that we have a fair chance of putting them right. The system is sufficiently flexible to allow for initiative, and we know we shall have to make changes to fit our future needs. We are in the happy situation of having our youth show an increasing interest in research work, so if we can successfully master our training problems we should have the good recruitment we consider essential for progress in research. The problem of "being small" can probably be solved, or at least remedied, through a combination of concentration and international collaboration.
In think it has now become clear to the greater part of our population, and specifically to a great number of influential persons, that if we in Norway are to maintain and develop our spiritual and material culture, we shall have to continue the progress in research. We thus hope that in the future, through a united effort of our Government, our trades and industries, and our research, we shall be able to contribute our share to the common fund of knowledge and shall be able also to use this knowledge to expand the social and economic life of our nation and contribute to the security of all free nations.
The International Geophysical Month
Authors: Helliwell R. A. , Martin L. H. 
Published: October 2006

For convenience, we summarize below some of the main advantages of the IGM concept.
1) Most organizations can mount and support intensive field operations for short periods.
2) High-quality data would be obtained, and the data could be processed more promptly than in long-term projects.
3) Laboratory equipment could in many instances be made available for field operations.
4) Top-caliber researchers would be available for field operations.
5) The participation of small research groups and of research workers from government and industry would be fostered.
6) Student participation would improve educational programs in, and attract needed talent to, the geophysical sciences.
7) Ship, satellite, and rocket observations could be scheduled for IGM's.
8) International scientific conferences scheduled to follow IGM's would attract working scientists.
It is not suggested that these short-term exercises should replace the long synoptic programs characteristic of the IGY. Rather it is proposed that they supplement and guide any such future long-term program. If adopted, they would produce many data of value for the planning and timing of the International Year of the Quiet Sun. To bring emphasis on special observations during the IQSY, International Geophysical Months might well be scheduled to coincide with the June and December solstices, to be followed by an IGM at an equinoctial period. This would provide periods for concentrated sampling—periods in somewhat the same category as the Regular World Intervals adopted during the IGY. The more elaborate experiments could be confined to the International Geophysical Months, so that only those studies for which continuous observations are essential would be scheduled for the entire period. The duration of an International Geophysical Month would be sufficient for carrying out experiments requiring moving platforms such as ships, rockets, or satellites.
It is recommended that every effort be made to schedule the first IGM during the June solstice in 1962. This initial effort could well be followed by the scheduling of IGM's during the December solstice in 1962 and the March equinox in 1963. These exercises would provide information important to the planning and scheduling of the IQSY.
Intracellular Infection and the Carrier State
Authors: Smadel Joseph E. 
Published: October 2006

The evidence summarized in this article is sufficient to support conclusions as follows.
1) Antibiotics penetrate rapidly into mammalian cells and inhibit multiplication of susceptible microbes within the cell as promptly and effectively as they inhibit multiplication of such microbes outside the cell. This is consistent with clinical experience.

2) Death of individual organisms inside mammalian cells bathed in medium containing antibiotics continues over several weeks but may not proceed
pari passu
with time. This observation supports the as yet meager clinical data, which suggest that eradication of the typhoid carrier state may be accomplished through antibiotic therapy, provided (i) the proper antibiotic is selected; (ii) it is administered in amounts sufficient to obtain continuous suppression of growth of intracellular organisms; and (iii) the regimen is maintained for 2 or 3 weeks.

3) The actual cause of death and destruction of intracellular microbes in treated cells remains an enigma. To attribute this to inanition or senescence of the organisms, without describing mechanisms, is to avoid the issue. The hypotheses dealing with inactivation of intracellular microbes by intracellular antimicrobial substances and antibodies deserve to be explored.
4) Evidence from the ward and laboratory suggests that infected cells can clear themselves of invading pathogens and recover. Although antibiotics have played the major role in demonstrating this in the laboratory, it is possible that they do nothing more than hold the intruders in abeyance while natural defense mechanisms of the cell gain the upper hand. Certainly such cellular mechanisms must provide a potent force for survival; otherwise, why would 98 percent of typhoid patients fail to become chronic carriers?
5) The continued study of infections, including the carrier state, with a view to understanding the abnormalities created by the multiplying intracellular microbe and the means by which the cell corrects these and eliminates the intruder, should open new vistas in chemotherapy and immunology.
The Scientist in the Federal Service
Authors: Macy John W. 
Published: October 2006

The plus factors of the federal personnel system for scientists may be summarized briefly as follows.
1) We have a modern, progressive personnel system which compares very favorably in most respects with that of a good private laboratory.
2) Although our pay scale may still be a little below that of private employment, great progress has been made in the past 3 years, and we are now catching up rather than falling further behind.
3) We do about as well as private employment with respect to benefits such as group life insurance, health insurance, and retirement, although some companies pay a larger share of the costs.
4) We have a generous and flexible leave system.
5) We are especially strong on promotion programs, incentive awards, and career development opportunities on the basis of merit and demonstrated competence.
Ethics for an International Health Profession
Authors: Taylor Carl E. 
Published: October 2006

These thoughts about an ethic of international health can be summarized in a very free revision of the Hippocratic Oath:
I will share the science and art by precept, by demonstration, and by every mode of teaching with other physicians regardless of their national origin. I will try to help secure for the physicians in each country the esteem of their own people, and in collaborative work see that they get full credit.
I will strive to eliminate sources of disease everywhere in the world and not merely set up barriers to the spread of disease to my own people.
I will work for understanding of the diverse causes of disease, including the social, economic, and environmental. I will promote the well-being of mankind in all its aspects, not merely the bodily, with sympathy and consideration for a people's culture and beliefs.
I will strive to prevent painful and untimely death, and also to help parents to achieve a family size conforming to their desires and to their ability to care for their children. In my concern with whole communities I will never forget the needs of its individual members.