bluuebunny/crossref_metadata_2025 huggingface dataset:
Addictive Drugs: The Cigarette Experience
Authors: Schelling Thomas C.
Published: October 2006

Cigarettes are among the most addictive substances of abuse and by far the most deadly. In this country smokers know it and try to stop. Their success has been dramatic but partial and excruciatingly slow, and until recently quite uncoerced by government. Cigarettes and nicotine have characteristics distinct among addictive drugs, and some of these help explain why efforts to quit smoking are so often frustrated. Nicotine itself is the most interesting chemical in the treatment of addiction and, in some forms, can pose a dilemma: compromise by settling for pure nicotine indefinitely, or stay with cigarettes and keep trying to quit. Nicotine is not alone among addictive drugs in becoming increasingly identified with the poorer classes.
Widespread Dispersion of Neuronal Clones Across Functional Regions of the Cerebral Cortex
Authors: Walsh Christopher , Cepko Constance L.
Published: October 2006

The cerebral cortex of the mammalian brain has expanded rapidly during the course of evolution and acquired structurally distinguishable areas devoted to separate functions. In some brain regions, topographic restrictions to cell intermixing occur during embryonic development. As a means of examining experimentally whether such restrictions occur during formation of functional subdivisions in the rat neocortex, clonally related neocortical cells were marked by retroviral-mediated transfer of a histochemical marker gene. Clonal boundaries were determined by infection of the developing brain with a library of genetically distinct viruses and amplification of single viral genomes by the polymerase chain reaction. Many clonally related neurons in the cerebral cortex became widely dispersed across functional areas of the cortex. Specification of cortical areas therefore occurs after neurogenesis.
Persistent Increase in Brain Serotonin Turnover after Chronic Administration of LSD in the Rat
Authors: Díaz José-Luis , Huttunen Matti O.
Published: October 2006

Lysergic acid diethylamide at doses of 20 micrograms per kilogram per day was administered orally to rats for 1 month. Eighteen hours after the final dose a 25 to 30 percent increase in the synthesis and turnover of serotonin was noted, as well as a moderate but significant increase in the concentration of tryptophan (18 percent) and serotonin (13 percent) in the brain.
Nonconversion of
o
,
p
′-DDT to
p
,
p
′-DDT in Rats, Sheep, Chickens, and Quail
Authors: Bitman Joel , Cecil Helene C. , Fries George F.
Published: October 2006

The finding of appreciable quantities of
p
,
p
′-DDT after feeding
o
,
p
′-DDT to rats led to the proposal of a theory that an isomeric metabolic conversion occurs. The presence of
p
,
p
′-DDT as an impurity in supposedly pure samples of
o
,
p
′-DDT is the correct explanation for the appearance of
p
,
p
′-DDT. Purified
o
,
p
′-DDT and
14
C-labeled
o
,
p
′-DDT yielded no data to support the idea that
o
,
p
′-DDT is converted to the
p
,
p
′-DDT isomer.
Kinetic Path of Genes Undergoing Selection
Authors: Kirkman Henry N.
Published: October 2006

As natural populations approach genetic equilibrium, the various genes in the population are capable of assuming intermediate distributions that might not be anticipated from either the rate of the process or the final distribution of the genes. Since it is possible that many populations have not reached genetic equilibrium, the distribution of genes in natural populations may be a reflection of the kinetic path by which the genes approach equilibrium. Attention to kinetic path provides an explanation for an apparent discrepancy in recent studies of selection in man.
Immunochemical Detection of Minor Bases in Nucleic Acids
Authors: Sawicki Dorothea L. , Erlanger Bernard F. , Beiser Sam M.
Published: October 2006

Rabbits immunized with bovine serum albumin conjugates of 5-bromouracil, 5-iodouracil, and 6-methyladenosine produced antibodies specific for the bases. These antibodies were used to detect immunochemically 5-bromouracil and 6-methyladenosine in denatured DNA.
Morphine Tolerance and Dependence Induced by Intraventricular Injection
Authors: Eidelberg E. , Barstow C. A.
Published: October 2006

Injection of small quantities of morphine into the cerebral ventricular system of awake, relatively unrestrained, monkeys depressed or abolished operant food-reinforced lever pressing. After repeated injections progressively higher doses of morphine were needed to depress responding. Also, dependence could be demonstrated in these animals by precipitating specific abstinence signs with an antagonist.
The Sun's Work in a Cornfield
Authors: Lemon Edgar , Stewart D. W. , Shawcroft R. W.
Published: October 2006

After extensive field experiments, we developed SPAM, a comprehensive mathematical model that simulates energy and material exchange in the plant-air layer at the earth's interface. The model is based upon the conservation of energy, where the sun is the driving force. Our understanding and deficiencies were gauged initially by testing model predictions against actual experience with a relatively simple system—a cornfield. Climatic predictions are physically and biologically good enough for many applications, but they reveal inadequacies in our understanding of the fluid dynamics of airflow within the plant stand. Our present inability to measure or predict the degree of wetness of the soil surface hampers correct prediction of evaporation. Probably the most difficult problem to resolve is that of predicting how stomates open and close under drought stress, thus affecting both evaporation and photosynthesis in leaves. Along with resolution of these problems, the basic framework of the model can be adapted to more complex systems in nature, where variability is much greater than in an agricultural crop. The model in its present form can be used, with caution, as a powerful tool to help man order his priorities of plant community traits for whatever outcome he desires, be it food production, nature and water conservation, climate modification, or esthetic enjoyment.
Morphological Basis for a Mechanical Linkage in Otolithic Receptor Transduction in the Frog
Authors: Hillman D. E. , Lewis E. R.
Published: October 2006

Observations made with a scanning electron microscope confirm the binding of the stereocilia to a matchhead-like bulbous terminal at the apex of the kinocilium in frog saccular receptor cells. Since the kinocilium is shown to rest on a portion of the receptor cell that lacks the rigid cuticular base of the stereocilia, movement of the ciliary ensemble results in a "plunging-like" effect of the kinocilium which produces a distension of the membrane at its base. This membrane distension is envisaged as bringing about the ionic conductance changes necessary for the production of a generator potential and, thus, for the transduction of movement into vestibular nerve activity.
Oxygen-Carrying Iridium Complexes: Kinetics, Mechanism, and Thermodynamics
Authors: Vaska L. , Chen Loomis S. , Senoff C. V.
Published: October 2006

The rates of oxygenation and deoxygenation of a series of iridium complexes increase and decrease, respectively, with increasing electron-releasing tendency of the anionic ligands (A) attached to the metal atom in the oxygencarrying compounds, [IrA(CO)(Ph
3
P)
2
]. Calculated heats of oxygenation (—ΔH
2
0
), related to Ir-O
2
bond energies, are proportional to the previously reported O-O bond lengths in the oxygen adducts, [O
2
IrA(CO)(Ph
3
P)
2
].
Informational DNA Synthesis Distinguished from That of Nuclear DNA by Inhibitors of DNA Synthesis
Authors: Bell Eugene
Published: October 2006

With inhibitors of DNA synthesis used in the presence of ethidium bromide, it has been possible to distinguish between synthesis of informational DNA (I-DNA) and that of nuclear DNA. Hydroxyurea depresses I-DNA synthesis preferentially but does not affect DNA transport between cell compartments. 5-Fluorodeoxyuridine and cytosine arabinoside reduce synthesis of I-DNA to a much lesser degree than that of nuclear DNA.
Alkyl Isocyanates as Active Site-Specific Inhibitors of Chymotrypsin and Elastase
Authors: Brown William E. , Wold Finn
Published: October 2006

Alkyl isocyanates react specifically with the two serine proteinases, chymotrypsin and elastase, to yield inactive enzyme derivatives containing 1 mole of reagent per mole of enzyme. Octyl isocyanate inactivates chymotrypsin only, while butyl isocyanate inactivates both enzymes but shows greater efficiency toward elastase than toward chymotrypsin. These reagents may thus represent unique chemical "yardsticks" for the measurement of the relative dimensions of the active sites of the two very similar enzymes.
Uranium Distributions in Archeologic Ceramics: Dating of Radioactive Inclusions
Authors: Zimmerman D. W.
Published: October 2006

Small mineral grains (10 to 50 micrometers) of high uranium concentration (100 to 3000 parts per million) were located in polished sections of eight potsherds from Cyprus, England, Greece, and Mexico by induced fission-track mapping. Most of the grains were identified as zircons or apatites by a microprobe attachment to a scanning electron microscope. The advantages in using such radioactive grains for thermoluminescence dating and alpha-recoil track dating are discussed.
Leech-Repellent Property of Eastern Red-Spotted Newts,
Notophthalmus viridescens
Authors: Pough F. Harvey
Published: October 2006

Eastern red-spotted newts (
Notophthalmus viridescens
, Salamandridae) are rarely attacked by leeches. This protection is not shared by related salamandrids or by
Ambystoma
(Ambystomatidae). Tetrodotoxin is not the repellent. The immunity of
Notophthalmus
to leech parasitism is probably most significant in its aquatic stages, although the terrestrial efts are also protected.
Nuclear Acidic Protein Changes during Differentiation in
Physarum polycephalum
Authors: LeStourgeon Wallace M. , Rusch Harold P.
Published: October 2006

A class of acidic nuclear phosphoproteins has been isolated throughout the mitotic cycle and at two points during differentiation in the slime mold
Physarum polycephalum
. The electrophoretic profiles of these proteins are reproducible and unchanging throughout the mitotic cycle, but reproducible changes occur during differentiation. The proteins are rapidly synthesized after mitosis, and their molecular weights range from 34,000 to 88,000. The proteins rapidly incorporate [
32
P]orthophosphate, and the content of alkali-labile phosphate increases 20 percent during the period after DNA synthesis. The proteins comprise 6.5 percent by dry weight of nuclear material while the DNA comprises about 5.5 percent. These acidic nuclear proteins may have a role in control of gene activity.
Selection of Ribosomal Mutants by Antibiotic Suppression in Yeast
Authors: Bayliss Frank T. , Vinopal Robert T.
Published: October 2006

Wild-type
Saccharomyces cerevisiae
is highly resistant to streptomycin. A histidine auxotroph was found which could grow without histidine in the presence of high concentrations of streptomycin. Selection for derivatives of this strain which could be suppressed by much lower concentrations of streptomycin yielded streptomycin-sensitive mutants which are cold-sensitive and have altered ribosomal profiles.
Prehistory of the Formosan Uplands
Authors: Treistman Judith M.
Published: October 2006

Recent archeological surveys in the central mountain ranges of Formosa show human occupation of considerable antiquity. The pattern of ecological adaptation which dichotomizes Southeast Asia characterized prehistoric Formosan settlement.
Backward Enhancement?
Authors: Dember William N. , Stefl Mary
Published: October 2006

Presentation of a masking stimulus enhances, rather than detracts from, detectability of certain multisegment targets. Present theories of backward masking cannot account for this "backward enhancement" effect, which resembles another puzzling phenomenon, previously reported as target recovery or disinhibition. An explanation in terms of interaction between retinal excitatory and inhibitory fields is offered.
Human Sarcomas Contain RNA Related to the RNA of a Mouse Leukemia Virus
Authors: Kufe D. , Hehlmann R. , Spiegelman S.
Published: October 2006

Labeled DNA complementary to the RNA of the Rauscher leukemia virus was hybridized with RNA from the polysome fraction of human sarcomas. Eighteen out of 25 specimens contained RNA possessing homology to the RNA of the mouse leukemia virus but not to that of the unrelated viruses causing mammary tumors in mice or myeloblastosis in chickens. Further, no normal adult or fetal tissues showed significant amounts of RNA specific to mouse leukemia virus. It appears that human sarcomas contain RNA sequences homologous to those found in an agent related to a virus known to cause sarcomas in mice.
Cellular Site of Glucocorticoid-Receptor Complex Formation
Authors: Levinson Barbara B. , Baxter John D. , Rousseau Guy G. , Tomkins Gordon M.
Published: October 2006

The cellular site of binding of dexamethasone by specific glucocorticoid receptors in cultured hepatoma cells was investigated with the use of certain mercurials.
p
-Chloromercuribenzene sulfonate and
p
-chloromercuribenzoate inhibit the binding of steroid by receptors in cell-free extracts, but they allow the steroid-receptor complex to form in whole cells. In contrast, HgCl
2
inhibits binding both in extracts and cells. Since both organic mercury compounds, unlike HgCl
2
, do not readily enter intact cells, it appears that the specific steroid binding occurs inside the cell rather than at the cell membrane.
Innervation of the Hamster Harderian Gland
Authors: Bucana Corazon D. , Nadakavukaren Mathew J.
Published: October 2006

Harderian glands of male and female hamsters have nerve endings associated with the secretory cells, myoepithelial cells, and the blood vessels. The nerve endings adjacent to the myoepithelial cells also have myoneural junctions.
Mariner 9 S-Band Martian Occultation Experiment: Initial Results on the Atmosphere and Topography of Mars
Authors: Kliore A. J. , Cain D. L. , Fjeldbo G. , Seidel B. L. , Rasool S. I.
Published: October 2006

A preliminary analysis of 15 radio occultation measurements taken on the day side of Mars between 40°S and 33°S has revealed that the temperature in the lower 15 to 20 kilometers of the atmosphere of Mars is essentially isothermal and warmer than expected. This result, which is also confirmed by the increased altitude of the ionization peak of the ionosphere, can possibly be caused by the absorption of solar radiation by fine particles of dust suspended in the lower atmosphere. The measurements also revealed elevation differences of 13 kilometers and a range of surface pressures between 2.9 and 8.3 millibars. The floor of the classical bright area of Hellas was found to be about 6 kilometers below its western rim and 4 kilometers below the mean radius of Mars at that latitude. The region between Mare Sirenum and Solis Lacus was found to be relatively high, lying 5 to 8 kilometers above the mean radius. The maximum electron density in the ionosphere (about 1.5 × 10
5
electrons per cubic centimeter), which was found to be remarkably constant, was somewhat lower than that observed in 1969 but higher than that observed in 1965.
Ethanol Produces Muscle Damage in Human Volunteers
Authors: Song Sun K. , Rubin Emanuel
Published: October 2006

Repeated administration of ethanol (42 percent of total calories) for 28 days increased serum creatine phosphokinase activity and produced ultrastructural changes in skeletal muscle of human volunteers. The data suggest that alcoholic myopathy results from ethanol toxicity, rather than from nutritional or other factors.
Lunar Anorthosite 15415: Texture, Mineralogy, and Metamorphic History
Authors: James Odette B.
Published: October 2006

Lunar anorthosite 15415 consists almost entirely of anorthite (homogeneous anorthite 96.6 molecule percent), with accessory diopsidic augite and traces of hypersthene, ilmenite, and a silica mineral. The rock has had a complex metamorphic history. The texture reflects at least two episodes of shearing (followed by intense and partial recrystallization, respectively), one episode of cataclastic deformation, and one or more episodes of shattering and fragmentation.
L-Leucine: A Neuroactive Substance in Insects
Authors: Tashiro Shigeki , Taniduchi Eiji , Eto Morifusa
Published: October 2006

A compound was isolated from the blood of silkworm larvae,
Bombyx mori
, which had been prostrated with DDT; this compound increased the spontaneous discharge in the isolated abdominal nerve cord of the American cockroach,
Periplaneta americana
. The compound was identified as L-leucine.
Crystallization Studies of Lunar Igneous Rocks: Crystal Structure of Synthetic Armalcolite
Authors: Lind M. D. , Housley R. M.
Published: October 2006

Crystals of armalcolite, Mg
0.5
Fe
0.5
Ti
2
O
5
, up to several millimeters in length have been grown from a glass initially having the composition of lunar rock 10017. A single-crystal x-ray study has confirmed that the crystals are isomorphous with pseudobrookite and has shown that the cations are strongly ordered, with the Ti
4+
ions occupying the 8
f
sites and the Fe
2+
and Mg
2+
ions randomly distributed over the 4
c
sites. An examination of karrooite, MgTi
2
O
5
, has revealed a similar distribution of Mg
2+
and Ti
4+
ions. A reexamination of earlier x-ray and Mössbauer data for pseudobrookite, Fe
2
TiO
5
, has shown that it is more consistent with this type of ordering than with the inverse structure that has been generally assumed.
Attentiveness to Sensory Stimuli: Central Control in Locusts
Authors: Camhi Jeffrey M. , Hinkle Maija
Published: October 2006

Wind-angle changes evoke yaw-correcting deflections of the abdomen in tethered locusts, but only if the wings are beating. In flight, the central neuronal flight motor drives abdominal motoneurons in rhythmic bursts. Wind angle inputs, which are inadequate alone to drive these motoneurons, alter the number of spikes per burst, and the alterations are reciprocal in opposite nerves. Burst frequency and phase are unaffected.
Locust Motoneurons: Bursting Activity Correlated with Axon Diameter
Authors: Hinkle Maija , Camhi Jeffrey M.
Published: October 2006

A group of abdominal motoneurons in the locust can be driven by either or both of two central neuronal oscillators of different characteristic frequencies. Much of the motor cells' complex activity can be explained by the varying strengths of activation from these two rhythmic sources and by a cell-to-cell gradation in sensitivity to driving inputs, a property that is correlated with axon diameter.
Seminal Vesicle Formation and Specific Male Protein Secretion by Female Cells in Allophenic Mice
Authors: Mintz Beatrice , Domon Masaharu , Hungerford David A. , Morrow John
Published: October 2006

The relation of cellular sex genotype to phenotype was examined in seminal vesicles of adult allophenic mice with cellular sex chromosome mosaicism. Each animal originated from conjoined blastomeres of an embryo of female (XX) and one of male (XY) constitution, from different inbred strains. Cells of both sexes were detected in bone marrow and certain other somatic tissues; cellular sex of seminal vesicles was deduced from strain-associated electrophoretic variants of proteins coded for at autosomal loci. Seminal vesicles composed partly or entirely of female cells were found in male and pseudohermaphrodite individuals. In a pseudohermaphrodite, both allelic variants of the tissue-specific normal male seminal vesicle protein (
Svp
-locus) were present, signifying that female as well as male cells were synthesizing the protein. Male-determining factors on the Y chromosome are thus not required in cells that differentiate into functional seminal vesicles.
Tissue Factor (Thromboplastin): Localization to Plasma Membranes by Peroxidase-Conjugated Antibodies
Authors: Zeldis Steven M. , Nemerson Yale , Pitlick Frances A. , Lentz Thomas L.
Published: October 2006

Peroxidase-conjugated antibodies were used to determine the histologic and cytologic localization of bovine and human tissue factor (thromboplastin). Tissue factor antigen was found in highest concentration in the intima of blood vessels, particularly in the plasma membranes of endothelial cells and in human atheromatous plaques. Tissue factor was also found limited to the plasma membranes of many cell types. The presence of tissue factor in the plasma membranes of endothelial cells and atheromata suggests that it may play a significant role in hemostasis and thrombosis.
Ultrastructural Evidence for Nephropathy Induced by Long-Term Exposure to Small Amounts of Methyl Mercury
Authors: Fowler Bruce A.
Published: October 2006

A low dose of methyl mercuric chloride fed to female rats for 12 weeks caused extrusion of numerous cytoplasmic masses from kidney proximal tubule cells of the pars recta segment. These masses were characterized ultrastructurally by the presence of a smooth endoplasmic reticulum aggregate. The in vivo metabolism of methyl mercury to inorganic mercury may produce this effect and account for the proteinuria observed in persons occupationally exposed to organic mercury compounds.
H-2 Antigen on Cell Membranes: An Explanation for the Alteration of Distribution by Indirect Labeling Techniques
Authors: Davis William C.
Published: October 2006

The distribution of H-2 isoantigens on the plasma membrane of lymphocytes and thymocytes was studied with ferritin-conjugated alloantibody. The spatial arrangement of the membrane components which possess H-2 isoantigens is markedly altered by the attachment of a second antibody, directed toward mouse gamma globulin or ferritin; the second antibody appears to cause the aggregation of the sensitized H-2 antigens into discrete zones on the cell membrane. Other membrane antigens may be equally affected by indirect labeling techniques and, thus, topographic analysis of the antigenic structure should be done with antibody that is directly conjugated.
Thyroid Hormone Influence upon Lung Surfactant Metabolism
Authors: Redding Ralph A. , Douglas William H. J. , Stein Myron
Published: October 2006

Thyroid administration and thyroidectomy in the rat profoundly affect the morphological characteristics of the type II pneumonocyte and the quantitative harvest of lung surfactant obtained from alveolar washings. The correlation of the ultrastructural changes with quantitative alterations in lung surfactant is evidence that the lamellar bodies within this cell are the source of the surface-active phospholipids utilized at the air-liquid interphase of lung alveoli. Our findings suggest that in the rat, L-thyroxine may be a potent regulator of lung surfactant metabolism.
Carcinoembryonic Antigen Present in Human Colonic Neoplasms Serially Propagated in Hamsters
Authors: Goldenberg David M. , Hansen Hans J.
Published: October 2006

Carcinoembryonic antigen, as measured by radioimmunoassay, is present in two different human colonic tumors that have been serially transplanted and maintained in the cheek pouches of unconditioned, adult golden hamsters. This finding shows that a human tumor-associated antigen can be produced in an animal host.
Matanchén Complex: New Radiocarbon Dates on Early Coastal Adaptation in West Mexico
Authors: Mountjoy Joseph B. , Taylor R. E. , Feldman Lawrence H.
Published: October 2006

Samples of marine shell from archeological context on the coast of Nayarit, Mexico, have given radiocarbon determinations of 1810 ± 80 B.C., 2000 ± 100 B.C., and 2100 ± 100 B.C. Even with maximum correction for upwelling these are the earliest dates for coastal occupation in West Mexico north of Acapulco, Guerrero. Analysis of the midden contents has provided new insights regarding early coastal adaptation.
Predation of Schistosomiasis Vector Snails by Ostracoda (Crustacea)
Authors: Sohn I. G. , Kornicker L. S.
Published: October 2006

An ostracod species of
Cypretta
is an effective predator in laboratory experiments on 1- to 3-day-old
Biomphalaria glabrata
, a vector snail of the blood fluke that causes the tropical and subtropical disease schistosomiasis.
Iodine Metabolism: Preferential Renal Excretion of Iodide Derived from Triiodothyronine Deiodination
Authors: Shimoda Shin-Ichi , Greer Monte A.
Published: October 2006

Measurements were made in rats of the relative rates of accumulation in urine or in the thyroid of radioactive iodide derived from simultaneous injections of
131
I-labeled triiodothyronine and
125
I-labeled iodide. The data indicate that deiodination of triiodothyronine by the kidney results in a loss into the urine of iodine which does not enter the general body iodide pool. This renal "iodide leak" should be considered in kinetic models of iodine metabolism.
1-Methyladenine Biosynthesis in Starfish Ovary: Action of Gonad-Stimulating Hormone in Methylation
Authors: Shirai H. , Kanatani H. , Taguchi S.
Published: October 2006

Gonad-stimulating substance, a hormonal peptide released from the nervous system of starfishes, acts on the ovary to produce 1-methyladenine, an inducer of oocyte maturation. Addition of methionine to the incubation mixture of ovarian fragments and gonad-stimulating substance enhanced the production of 1-methyladenine, whereas ethionine inhibited it. Incubation of ovarian tissue with methionine alone failed to produce 1-methyladenine. Use of a radioactive label showed that methionine is a methyl donor in the biosynthesis of 1-methyladenine, suggesting that gonad-stimulating substance is involved in the methylation process.
Oxygen Affinity in Red Cells: Changes Induced in vivo by Propranolol
Authors: Oski Frank A. , Miller Leonard D. , Delivoria-Papadopoulos Maria , Manchester Joel H. , Shelburne James C.
Published: October 2006

Propranolol, a blocking agent for the beta adrenergic receptor, produces a redistribution of 2,3-diphosphoglycerate in the red cell. At concentrations of 3.3 × 10
-5
M
, 2,3-diphosphoglycerate in the red cell membrane becomes unbound in vitro. The administration of propranolol to humans produces similar changes and results in a decrease in the affinity of hemoglobin for oxygen.
Sound Production in Scolytidae: Chemostimulus of Sonic Signal by the Douglas-Fir Beetle
Authors: Rudinsky J. A. , Michael R. R.
Published: October 2006

Stridulation by male
Dendroctonus pseudotsugae
was recorded in response to the natural female attractant (frass) or to three synthetic components of the attractant (frontalin, 3-methyl-2-cyclohexen-1-one, and trans-verbenol). This stridulation was acoustically distinct from stress sound and correlated with known attraction behavior. The response of female
D. pseudotsugae
to male stridulation— negation of her attraction—was induced by playback of recorded attractant stridulation but not by that of stress sounds. Acoustic communication must be more important in scolytid behavior than it was heretofore believed to be.
Sex Pheromones of Summer Fruit Tortrix Moth
Adoxophyes orana
: Two Synergistic Isomers
Authors: Meijer G. M. , Ritter F. J. , Persoons C. J. , Minks A. K. , Voerman S.
Published: October 2006

Both
cis
-9- and
cis
-11-tetradecenyl acetate were isolated from 2500 virgin females of the summer fruit tortrix moth
Adoxophyes orana
(F.v.R.) by gel permeation, column chromatography on silica gel, and gas chromatography. Their chemical, physical, and biological properties were identical to those of the synthetic compounds. In contrast to the single compounds, mixtures of these pheromones were highly active in laboratory and field tests. Catches, in traps, with the pheromone mixture were comparable to those obtained when live females were used as bait. This is the first example of a member of the lepidoptera in which the presence of two isomers is an absolute requirement for activity in laboratory and in field experiments.
GABA Catabolism: Localization of Succinic Semialdehyde Dehydrogenase in Brain Motor and Sensory Nuclei
Authors: Sims K. L. , Weitsen H. A. , Bloom F. E.
Published: October 2006

The localization of brain succinic semialdehyde dehydrogenase, a specific gamma-aminobutyric acid degradative enzyme, could potentially yield valuable information concerning the function of the enzyme. Application of a new histochemical technique for this enzyme has revealed characteristic patterns of neuronal staining that are consistent within embryologically and functionally similar nuclei of the brainstem of the rat.
Griseofulvin: A Teratogenic Study
Authors: Klein M. F. , Beall J. R.
Published: October 2006

Griseofulvin, a fungistatic agent, was administered in oral doses of 125 to 1500 milligrams per kilogram per day to pregnant rats during organogenesis. Evaluation of the offspring from dams treated with the largest doses, 63 and 75 times a therapeutic dose in man, indicated decreased survival rates and a syndrome of malformations.
Meiosis in Triploid All-Female Fish (
Poeciliopsis
, Poeciliidae)
Authors: Cimino Michael C.
Published: October 2006

Prior to meiosis in triploid gynogenetic all-female forms of
Poeciliopsis
, the chromosome number of the nucleus of the triploid oogonium is raised endomitotically to hexaploid. Recombination does not occur; instead, a triploid ovum with a genetic complement identical to that of the mother is produced by two conventional meiotic divisions. Sperm from a sympatric gonochoristic (bisexual) species stimulates the ovum to develop, but paternal genes are not incorporated into the zygote. This is the first cytologically verified case of natural endomitosis in the egg production in fish.
Biosynthesis of α and β-Ecdysones from Cholesterol outside the Prothoracic Gland in
Bombyx mori
Authors: Nakanishi Koji , Moriyama Hiroshi , Okauchi Tetsuo , Fujioka Shoji , Koreeda Masato
Published: October 2006

Labeling experiments have established that cholesterol is converted into α- and β-ecdysones in isolated abdomens of silkworm larvae. Since the isolated abdomens do not contain the prothoracic glands, a doubt is cast on the long-standing principle in insect endocrinology that the prothoracic glands are the source of ecdysone secretion.
Restoration of Antibody-Forming Capacity in Cultures of Nonadherent Spleen Cells by Mercaptoethanol
Authors: Chen Chang , Hirsch James G.
Published: October 2006

Populations of mouse spleen cells, without those cells that adhere to glass or plastic, exhibit little or no capacity for formation of antibody to sheep erythrocytes in the Mishell-Dutton culture system. When 5 × 10
-5
M
mercaptoethanol is added to the culture medium, the antibody-forming capacity of these nonadherent spleen cells is restored to that of unfractionated spleen cells.
The Chimpanzee as an Animal Model for Investigating Alcoholism
Authors: Pieper W. A. , Skeen Marianne J. , McClure Harold M. , Bourne Peter G.
Published: October 2006

Young chimpanzees (
Pan troglodytes
) will accept ethanol in quantities sufficient to produce symptoms of withdrawal when ethanol is subsequently discontinued. Mild to severe symptoms of physical dependence, including grand mal seizures, are observed when ethanol is abruptly withdrawn after 6 to 10 weeks of chronic oral intake. In addition, the rate of disappearance of ethanol in blood increased during periods of chronic ingestion, an indication of developing metabolic tolerance. These results suggest that the young chimpanzee may be a suitable model for experimental studies of alcoholism.
Cloud Seeding Experiments: Lack of Bias in Florida Series
Authors: Brier Glenn W. , Cotton Gerald F. , Simpson Joanne , Woodley William L.
Published: October 2006

There has been concern about the possibility of selection bias in cloud seeding experiments. Covariates and experimental design have been used to obtain an estimate of this bias. The results indicate that there was no selection bias in the Caribbean and Florida series of cloud seeding experiments.
Immunologic Tolerance: Role of the Regional Lymph Node
Authors: Friedlaender Mitchell H. , Baer Harold
Published: October 2006

Dansyl chloride, a skin sensitizer when injected in complete Freund's adjuvant, induced marked tolerance and no sensitization when applied to the intact skin of guinea pigs. Application of this chemical to alymphatic skin islands failed to induce tolerance or sensitization. Lymphatic connections between skin and regional lymph nodes were essential for the development of immunologic tolerance.
Trophic Regulation of Acetylcholine Sensitivity of Muscle: Effect of Electrical Stimulation
Authors: Drachman Daniel B. , Witzke Fredrica
Published: October 2006

Denervation of skeletal muscle results in a spread of acetylcholine sensitivity over the entire surface membrane. Electrical stimulation, programmed to mimic the normal activity pattern, was applied continuously to the denervated rat diaphragm in vivo. After 4 days, the acetylcholine sensitivity was far less in the stimulated diaphragms than in denervated controls. Muscle activity may account for "neurotrophic" regulation of the acetylcholine sensitivity.
Polyadenylic Acid Sequences in the Virion RNA of Poliovirus and Eastern Equine Encephalitis Virus
Authors: Armstrong John A. , Edmonds Mary , Nakazato Hiroshi , Phillips Bruce A. , Vaughan Maurice H.
Published: October 2006

Poliovirus virion RNA contains a single covalently bound sequence of polyadenylic acid which is approximately 49 nucleotides long. A single, slightly longer polyadenylic acid sequence is contained in Eastern Equine Encephalitis virus RNA. Since these viruses are otherwise dissimilar these sequences may play a common role in viral replication, possibly in translation of the viral RNA.
Cholesteric Liquid Crystal-Like Structure of the Cuticle of
Plusiotis gloriosa
Authors: Pace Anderson
Published: October 2006

The toroidal but parallel array of planes of unidirectionally oriented molecules believed to characterize cholesteric liquid crystals also gives rise to certain geometrical patterns. The reality of this structure is demonstrated by micrographic evidence.
Terrestrial Atmospheric Composition from Stellar Occultations
Authors: Hays P. B. , Roble R. G. , Shah A. N.
Published: October 2006

Stellar ultraviolet light transmitted through the earth's upper atmosphere is strongly absorbed by ozone and molecular oxygen. The stellar ultraviolet photometers aboard the Orbiting Astronomical Observatory (OAO-2) satellite have measured the intensity changes of several stars during occultation of the star by the earth's atmosphere. From the occultation data the nighttime vertical number density profiles of molecular oxygen at altitudes from 120 to 200 kilometers and of ozone at altitudes from 60 to 100 kilometers have been obtained.
Triacylglycerols Characteristic of Porpoise Acoustic Tissues: Molecular Structures of Diisovaleroylglycerides
Authors: Varanasi Usha , Malins Donald C.
Published: October 2006

More than two-thirds of the triacylglycerols from the acoustic tissues of the porpoise (
Tursiops gilli
) consist of 2 moles of isovaleric acid for every 1 mole of long-chain acids. Cranial blubber, which has no distinct acoustic function, does not contain these unusual glycerides. The presence of large amounts of diisovaleroylisopentadecanoylglycerol suggests that this structure may be particularly important in sound transmission through lipid-protein matrices.
Crystalline Fraction I Protein: Preparation in Large Yield
Authors: Chan P. H. , Sakano Katsuhiro , Singh Shalini , Wildman S. G.
Published: October 2006

About 1 milligram of twice-recrystallized fraction I protein of constant specific ribulose diphosphate carboxylase activity per gram of leaves (fresh weight) has been obtained from each of seven different species of
Nicotiana
and 14 reciprocal, interspecific F
1
hybrids. Crystals are produced from homogenates that have only been centrifuged to remove particulate matter.
Cytochalasin B Inhibits Lymphotoxin Production by Antigen-Stimulated Lymphocytes
Authors: Yoshinaga Masaru , Waksman Byron H. , Malawista Stephen E.
Published: October 2006

Lymph node cells of rats sensitized with hen ovalbumin produced lymphotoxin after 6 to 12 hours of exposure to specific antigen. Lymphotoxin was assayed by its cytotoxicity for fibroblasts from syngeneic embryos during a 72-hour incubation. Cytochalasin B inhibited lymphotoxin production, as well as later DNA synthesis, at concentrations (0.1 to 5.0 micrograms per milliliter) comparable to those which affect microfilament function and cell motility in other systems, and this inhibition was reversible. Binding of antigen was not affected.
Salicylate: A Structure-Activity Study of its Effects on Membrane Permeability
Authors: Levitan Herbert , Barker Jeffery L.
Published: October 2006

Salicylate and benzoate, and their analogs, reversibly increase the membrane potential and conductance of identified molluscan neurons by increasing potassium conductance and decreasing chloride conductance. The relative potencies of these compounds were closely correlated with their octanol-water partition coefficients and their
pK
a
values.
Cytochalasin B: Inhibition of D-2-Deoxyglucose Transport into Leukocytes and Fibroblasts
Authors: Zigmond Sally H. , Hirsch James G.
Published: October 2006

Cytochalasin B inhibits transport of D-2-deoxyglucose and of glucosamine into leukocytes, but does not impair uptake of leucine by these cells. This inhibitory action is rapid and reversible, and results in suppression of glycolysis. Cytochalasin B also blocks transport of D-2-deoxyglucose, but not of leucine, into mouse L strain fibroblasts.
A Fungal Gene for Antibiotic Resistance on a Dispensable ("B") Chromosome
Authors: Miao Vivian P. , Covert Sarah F. , VanEtten Hans D.
Published: October 2006

A family of cytochrome P-450 (
Pda
) genes in the pathogenic fungus
Nectria haematococca
is responsible for the detoxification of the phytoalexin pisatin, an antimicrobial compound produced by garden pea (
Pisum sativum
L.). The
Pda6
gene was mapped by electrophoretic karyotype analysis to a small meiotically unstable chromosome that is dispensable for normal growth. Such traits are typical of B chromosomes. The strains of
Nectria
studied here have no sequences that are homologous to the
Pda
family other than
Pda6
and therefore demonstrate that unique, functional genes can be found on B chromosomes. Unstable B chromosomes may be one mechanism for generating pathogenic variation in fungi.
Low Affinity Interaction of Peptide-MHC Complexes with T Cell Receptors
Authors: Matsui Kiyoshi , Boniface J. Jay , Reay Philip A. , Schild Hansjörg , de St. Groth Barbara Fazekas , Davis Mark M.
Published: October 2006

The interaction of antigen-specific T cell receptors (TCRs) with their ligands, peptides bound to molecules of the major histocompatibility complex (MHC), is central to most immune responses, yet little is known about its chemical characteristics. The binding to T cells of a labeled monoclonal antibody to the TCR was inhibited by soluble class II MHC heterodimers complexed to different peptides. Inhibition was both peptide- and TCR-specific and of low affinity, with a
K
D
= 4 × 10
-5
to 6 × 10
-5
M, orders of magnitude weaker than comparable antibody-antigen interactions. This finding is consistent with the scanning nature of T cell recognition and suggests that antigen-independent adhesion precedes TCR engagement.
REM Sleep Induction by Physostigmine Infusion During Sleep
Authors: Sitaram N. , Wyatt Richard Jed , Dawson Susan , Gillin J. Christian
Published: October 2006

Physostigmine (an anticholinesterase agent that increases acetylcholine at the synapse), in a dose of 0.5 milligram, was given intravenously to seven normal human volunteers. When injected during rapid eye movement (REM) sleep, physostigmine woke the subjects, and when injected during non-REM sleep, it induced REM sleep. This result suggests that cholinergic mechanisms play a role in the induction of REM sleep and in modulating cortical arousal mechanisms.
11-Hydroxy-Δ
9
-tetrahydrocannabinol: Pharmacology, Disposition, and Metabolism of a Major Metabolite of Marihuana in Man
Authors: Lemberger Louis , Crabtree Ross E. , Rowe Howard M.
Published: October 2006

11-Hydroxy-Δ
9
-tetrahydrocannabinol, administered intravenously to man, produces psychologic and pharmacologic effects that persist for several hours. The drug and its metabolites are excreted in urine and feces for more than 1 week. The pharmacology, disposition, and metabolism of 11-hydroxy-Δ
9
-tetrahydrocannabinol mimic that of Δ
9
-tetrahydrocannabinol, thus providing evidence that Δ
9
-tetrahydrocannabinol (the major active component of marihuana) is converted to the 11-hydroxy compound in man, the latter compound being responsible for the effects.
Carbon Monoxide and Nitric Oxide Consumption in Polluted Air: The Carbon Monoxide-Hydroperoxyl Reaction
Authors: Westenberg A. A.
Published: October 2006

A recent laboratory measurement of the ratio of the rate constant for the reaction CO + HO
2
→ CO
2
+ OH relative to that for H + HO
2
→ 2OH indicates that the former reaction is probably faster than CO + OH → CO
2
+ H. On this basis a simple analysis is given showing that the calculated lifetime of nitric oxide in polluted atmospheres would be appreciably longer than that estimated on the assumption that the carbon monoxide-hydroperoxyl reaction may be neglected. A fast carbon monoxide-hydroperoxyl reaction implies that the cyclic consumption of carbon monoxide (an atmospheric sink) could occur even with no nitric oxide present.
Heat Capacity of Superconducting Ternary Molybdenum Sulfides
Authors: Viswanathan R. , Lawson A. C.
Published: October 2006

The heat capacities of AgMo
4
S
5
, PbMo
6
S
7
, and SnMo
5
S
6
are reported. These ternary molybdenum sulfides have been found to be bulk superconductors with very large values of electronic heat capacity coefficients and very low values of Debye temperatures.
Variation in Cardiac Glycoside Content of Monarch Butterflies from Natural Populations in Eastern North America
Authors: Brower Lincoln P. , McEvoy Peter B. , Williamson Kenneth L. , Flannery Maureen A.
Published: October 2006

A new spectrophotometric assay has been used to determine the gross concentration of cardiac glycoside in individual monarch butterflies. Adults sampled during the fall migration in four areas of eastern North America exhibited a wide variation in cardiac glycoside concentration. The correlation between spectrophotometrically measured concentrations and emetic dose determinations supports the existence of a broad palatability spectrum in wild monarch butterflies. The cardiac gylcoside concentration is greater in females than in males and is independent of the dry weight of the butterflies; contrary to prediction, both the concentration mean and variance decrease southward. The defensive advantage of incorporating cardiac glycosides may be balanced by detrimental effects on individual viability.
Double Moldavites in Southern Bohemia
Authors: Bouška Vladimír , Rost Rudolf
Published: October 2006

Two noteworthy finds of moldavites were made in southern Bohemia. In both cases two moldavites are thrust into each other. The collision evidently took place during the flight of an inhomogeneous swarm of moldavites, still plastic but already displaying almost definite aerodynamic shapes. It is the first time such moldavites have been encountered, and the authors propose to designate them as double moldavites.
Subtle Consequences of Methylmercury Exposure: Behavioral Deviations in Offspring of Treated Mothers
Authors: Spyker Joan M. , Sparber Sheldon B. , Goldberg Alan M.
Published: October 2006

Overt neurological impairment is the endpoint currently used to document a case of methylmercury poisoning. No consideration is given to possible subtle consequences. Offspring from mice exposed to methylmercury on day 7 or 9 of pregnancy were apparently unaffected during postnatal development. However, subtle behavioral differences between treated and control offspring were found when the overtly normal animals were tested in an open field and evaluated in a swimming apparatus at 1 month of age. Brain weight, protein, choline acetyltransferase, and cholinesterase were not significantly altered.
Receptors for Histamine Can Be Detected on the Surface of Selected Leukocytes
Authors: Melmon Kenneth L. , Bourne Henry R. , Weinstein Jacob , Sela Michael
Published: October 2006

Histamine insolubilized by chemical linkage via a protein or polypeptide carrier to Sepharose beads cannot penetrate cells. Even so, the resultant histamine-coated Sepharose binds leukocytes selectively. Despite the low molecular weight of histamine, the binding is via preformed cell membrane receptors and can be specifically and competitively blocked or reversed by antihistamines.
Chromosome Banding Patterns in Preimplantation Mouse Embryos
Authors: Nesbitt Muriel N. , Donahue Roger P.
Published: October 2006

The chromosomes of first cleavage mouse embryos show the same banding patterns after quinacrine mustard staining as do chromosomes of differentiated mouse cells. Whatever feature of chromosome structure the banding pattern reveals thus appears not to be altered during development and differentiation.
Fertility Impairment in Mice on a Low Fluoride Intake
Authors: Messer H. H. , Armstrong W. D. , Singer L.
Published: October 2006

Female mice maintained on a low fluoride diet over two generations showed a progressive decline in litter production. Mice receiving the same diet supplemented with fluoride reproduced normally and at consistent intervals. Addition of fluoride to the intake of females with demonstrated impaired fertility restored their reproductive capacity.
Adenosine 3′,5′-Monophosphate and N6-2'-O-Dibutyryl-Adenosine 3′,5′-Monophosphate Transport in Cells
Authors: Ryan Wayne L. , Durick Mary Ann
Published: October 2006

Incubation of Strain L cells in 0.15 millimolar adenosine 3′,5′-monophosphate (cyclic AMP) increase the intracellular level of cyclic AMP more than does incubation in dibutyryl cyclic AMP. The intracellular increase of cyclic AMP is greater with Strain L than with WI-38 cells. Similarly, cell division of Strain L cells is inhibited more by cyclic AMP. The experiments do not support the belief that dibutyryl cyclic AMP is transported better than cyclic AMP.
Lanthanide Complexes as Nuclear Magnetic Resonance Structural Probes: Paramagnetic Anisotropy of Shift Reagent Adducts
Authors: Horrocks William DeW. , Sipe James P.
Published: October 2006

Magnetic anisotropy measurements on single crystals of a series of paramagnetic 8-coordinate lanthanide shift reagent adducts of the type Ln[(CH
3
)
3
CCOCHCOC(CH
3
)
3
]
3
(4-CH
3
C
5
H
4
N)
2
have been made for the following lanthanides: praseodymium, neodymium, samarium, europium, terbium, dysprosium, holmium, erbium, thulium, and ytterbium. The susceptibility tensors are highly anisotropic and nonaxial. Dipolar nuclear magnetic resonance shifts evaluated from the solid-state data are in satisfactory agreement with the solution results.
Behavioral Changes of Chronic Schizophrenic Patients Given L-5-Hydroxytryptophan
Authors: Wyatt Richard J. , Vaughan Thomas , Galanter Marc , Kaplan Jonathan , Green Richard
Published: October 2006

Oral administration of the serotonin precursor L-5-hydroxytryptophan with a peripheral decarboxylase inhibitor produced mild to moderate improvement in six of seven chronic undifferentiated schizophrenic patients who were resistant to phenothiazine treatment, as compared to an oral administration of a placebo. Two of four chronic paranoid schizophrenic patients who were resistant to phenothiazine treatment became worse with 5-hydroxytryptophan, one improved. It is presumed that these psychological changes were directly or indirectly produced from increases in brain serotonin. Indirect data from animals and humans indicate that there may be an abnormality in serotonin metabolism in some schizophrenics. While our data are consistent with this hypothesis, other explanations for our data must be entertained.