bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased Intracellular Calcium Stimulates 3H‐Inositol Polyphosphate Accumulation in Rat Cerebral Cortical Slices
Authors: Baird John G. , Nahorski Stefan R.
Published: October 2006

Agents that increase the intracellular Ca2+ concentration have been examined for their ability to stimulate 3H‐inositol polyphosphate accumulation in rat cerebral cortex slices. Elevated extracellular K+ levels, the alkaloid sodium channel activator veratrine, the calcium ionophore ionomycin, and the marine toxin maitotoxin were all able to stimulate phosphoinositide metabolism. Certain features appear common to the agents studied. Thus, although [3H]inositol monophosphate, [3H]inositol bisphosphate ([3H]InsP2), and [3H]inositol trisphosphate were all stimulated, a proportionally greater effect was observed on [3H]InsP2 in comparison to stimulation by the muscarinic receptor agonist carbachol. However, only an elevated K+ level stimulated [3H]inositol tetrakisphosphate ([3H]InsP4) accumulation alone or produced marked synergy with carbachol on the formation of this polyphosphate. The results suggest that agents that elevate the cytoplasmic Ca2+ concentration in cerebral cells can increase the hydrolysis of membrane polyphosphoinositides. The pattern of the response differs from that produced by muscarinic receptor agonists and indicate that Ca2+‐dependent hydrolysis may involve different pools of lipids, phosphoinositidase C enzymes, or both. However, clear differences in the ability of these agents to stimulate InsP4, alone or in the presence of muscarinic agonist, suggest that factors other than a simple elevated intracellular Ca2+ concentration are implicated.
Enhancement of In Vivo Tyrosine Hydroxylation in the Rat Adrenal Gland Under Hypoxic Conditions
Authors: Hayashi Yasunori , Miwa Soichi , Lee Ken , Koshimura Kunio , Hamahata Keigo , Hasegawa Hiroshi , Fujiwara Motohatsu , Watanabe Yasuyoshi
Published: October 2006

We examined the effects of hypoxia (8% O2) on in vivo tyrosine hydroxylation, a rate‐limiting step for catecholamine synthesis, in the rat adrenal gland. The hydroxylation rate was determined by measuring the rate of accumulation of 3,4‐dihydroxyphenylalanine (DOPA) after decarboxylase inhibition. One hour after hypoxic exposure. DOPA accumulation decreased to 60% of control values, but within 2 h it doubled. At 2 h, the apparent Km values for tyrosine and for biopterin cofactor of tyrosine hydroxylase (TH) in the soluble fraction were unchanged, whereas the Vmax value increased by 30%. The content of total or reduced biopterin was unchanged, but the content of tyrosine increased by 80%. Tyrosine administration had little effect on DOPA accumulation under room air conditions but enhanced DOPA accumulation under hypoxia. After denervation of the adrenal gland, the hypoxia‐induced increase in DOPA accumulation and in the Vmax value was abolished, whereas the hypoxia‐induced increase in tyrosine content was persistent. These results suggest that in vivo tyrosine hydroxylation is enhanced under hypoxia, although availability of oxygen is reduced. The enhancement is the result of both an increase in tyrosine content coupled with increased sensitivity of TH to changes in tyrosine tissue content and of an increase in dependence of TH on tyrosine levels. The increase in the sensitivity of TH and in the Vmax value is neurally induced, whereas the increase in tyrosine content is regulated by a different mechanism.
Arachidonic Acid Liberated by Diacylglycerol Lipase Is Essential for the Release Mechanism in Chromaffin Cells from Bovine Adrenal Medulla
Authors: Rindlisbacher B. , Sidler M. A. , Galatioto L. E. , Zahler P.
Published: October 2006

Chromaffin cells from bovine adrenal medulla secrete catecholamines on stimulation with acetylcholine. In addition to the activation of the phosphatidylinositol cycle, arachidonic acid is generated, which was thought to be the result of phospholipase A2 activation. We have demonstrated in isolated plasma membranes of these cells that arachidonic acid is generated by a two‐step reaction of diacylglycerol and monoacylglycerol lipase splitting diacylglycerol, which originates from the action of phospholipase C on phosphatidylinositols. No phospholipase A2 activity could be detected in plasma membranes so far. External addition of arachidonic acid increases the release in the absence and in the presence of agonist. Inhibition of the diacylglycerol lipase by RHC 80267 suppresses the catecholamine release, which is restored on addition of arachidonic acid. This effect, however, is reversed by lipoxygenase inhibitors, indicating that it is not arachidonic acid itself, but one of its lipoxygenase products, that is essential for inducing exocytosis.
Lupus erythematosus: clinical and histopathological study of oral manifestations and immunohistochemical profile of epithelial maturation
Authors: Lourenço Silvia Vanessa , Nacagami Sotto Mirian , Constantino Vilela Maria Apparecida , Rodrigues Gonçalves de Carvalho Fabio , Rivitti Evandro A. , Menta Simonsen Nico Marcello
Published: October 2006

Background: Lupus erythematosus (LE) is an autoimmune disease of unknown cause. Prevalence of oral involvement in patients with LE is uncertain but may vary from 9 to 45% in patients with systemic disease and from 3 to 20% in patients with chronic cutaneous involvement.

Methods: Incidence of oral lesions of LE and their clinical aspects were investigated. Their histopathologic features were analyzed, and the status of epithelial maturation was assessed through the expression patterns of cytokeratins.

Results: Twenty‐six patients (from 188 examined) presented oral lesions of LE. Most of them were females (19) with systemic disease (11). Clinical aspects of these lesions varied, and lips and buccal mucosa were most affected. Histologically, lesions revealed lichenoid mucositis with perivascular infiltrate and thickening of basement. Cytokeratins profile showed hyperproliferative epithelium, with expression of CK5/6, and CK14 on all epithelial layers, CK16 on all suprabasal layers and CK10 on prickle cell layers only.

Conclusions: Oral lesions of LE show a variety of aspects, and their microscopic features are of a lichenoid mucositis with deep inflammatory infiltrate. Cytokeratins expression patterns are of hyperproliferative epithelium, and this phenomenon must be analyzed in relation to the inflammatory cytokines for a better understanding of the mechanisms of the disease.
Effect of ozone on oral cells compared with established antimicrobials
Authors: Huth Karin C. , Jakob Franz M. , Saugel Bernd , Cappello Christian , Paschos Ekaterini , Hollweck Regina , Hickel Reinhard , Brand Korbinian
Published: October 2006

Ozone has been proposed as an alternative antiseptic agent in dentistry based on reports of its antimicrobial effects in both gaseous and aqueous forms. This study investigated whether gaseous ozone (4 × 106 µg m−3) and aqueous ozone (1.25–20 µg ml−1) exert any cytotoxic effects on human oral epithelial (BHY) cells and gingival fibroblast (HGF‐1) cells compared with established antiseptics [chlorhexidine digluconate (CHX) 2%, 0.2%; sodium hypochlorite (NaOCl) 5.25%, 2.25%; hydrogen peroxide (H2O2) 3%], over a time of 1 min, and compared with the antibiotic, metronidazole, over 24 h. Cell counts, metabolic activity, Sp‐1 binding, actin levels, and apoptosis were evaluated. Ozone gas was found to have toxic effects on both cell types. Essentially no cytotoxic signs were observed for aqueous ozone. CHX (2%, 0.2%) was highly toxic to BHY cells, and slightly (2%) and non‐toxic (0.2%) to HGF‐1 cells. NaOCl and H2O2 resulted in markedly reduced cell viability (BHY, HGF‐1), whereas metronidazole displayed mild toxicity only to BHY cells. Taken together, aqueous ozone revealed the highest level of biocompatibility of the tested antiseptics.
Prolonging Effective Penicillin Action
Authors: Trumper Max , Hutter A. M.
Published: October 2006

(1) Single injections of penicillin in saline administered intramuscularly with ice applications at the site of the injection produced and maintained bacteriostatic levels for six to twelve hours in nine out of ten patients, nine of whom were diagnosed as having gonorrhea and one urethritis with extracellular diplococci.

(2) There was one failure, Subject No. 10, who received only 30,000 units.

(3) Eight of the patients with gonorrhea and the one patient with urethritis were cured (bacteriologically and clinically) by this single intramuscular injection of penicillin.
The Major Histocompatibility Complex of the Mouse
Authors: Klein Jan
Published: October 2006

Like physicists striving to develop a unified field theory, immunologists are attempting to bring order to the microcosmos of defense reactions. Indications are that one of the most important constants in this microcosmos is the major histocompatibility complex (MHC) of the species. A test of any interpretation of the MHC's role in immunity is how well it explains this system's polymorphism. One of the most crucial questions an MHC hypothesis must answer is: Why are there so many alleles at this complex?
1,25-Dihydroxyvitamin D in Biological Fluids: A Simplified and Sensitive Assay
Authors: Eisman J. A. , Hamstra A. J. , Kream B. E. , DeLuca H. F.
Published: October 2006

A competitive binding assay for 1,25-dihydroxyvitamin D [1,25-(OH
2
D] in plasma has been developed in which intestinal cytosol preparations from rachitic chicks are used as the binding protein. A new method of extraction and two new chromatographic procedures are used for this assay. The method is sensitive to as little as 10 picograms of 1,25-(OH)
2
D, and triplicate assays can be done on 5 milliliters of plasma. This assay shows that in the plasma of normal adult subjects there is a 1,25-(OH)
2
D concentration of 29 ± 2 picograms per milliliter, while none can be detected in the plasma of nephrectomized subjects and end-stage renal failure patients.
Douglas-Fir Tussock Moth: Sex Pheromone Identification and Synthesis
Authors: Smith Ronald G. , Daterman Gary E. , Daves G. Doyle
Published: October 2006

The sex pheromone of the Douglas-fir tussock moth
Orgyia pseudotsugata
(McDunnough) has been isolated and identified as (
Z
)-6-heneicosen-11-one. This compound and its E isomer have been synthesized and are highly potent in laboratory bioassays and field trials.
Luminous and Chromatic Flickering Patterns Have Opposite Effects
Authors: Kelly D. H.
Published: October 2006

When stimulated in phase by a sinusoidally flickering, uniform field, the red and green cone systems tend to inhibit each other. This inhibition is minimized by (i) counterphase (luminance) patterns or (ii) red/green (chromaticity) flicker. However, when (i) and (ii) are combined, the usual flickering-pattern effect is reversed: instead of enhancing chromatic flicker, counterphase patterns tend to suppress it.
Mechanism of Insulin-Induced Paralysis of Muscles from Potassium-Depleted Rats
Authors: Kao Ing , Gordon Albert M.
Published: October 2006

Zinc-free insulin elicited a reduction in the potassium conductance of muscle fibers from potassium-depleted muscle, which led to depolarization, blockade of action-potential mechanism, and paralysis. These changes are proposed as the mechanism of insulin-induced paralysis in patients with hypokalemic periodic paralysis. A similar effect by concanavalin A suggests that the effect may be mediated through the insulin receptors.
Oxidation of the Carcinogens Benzo[
a
]pyrene and Benzo[
a
]anthracene to Dihydrodiols by a Bacterium
Authors: Gibson David T. , Mahadevan Venkatanayarana , Jerina Donald M. , Yagi Haruhiko , Yeh Herman J. C.
Published: October 2006

A mutant strain of
Beijerinckia
, after growth with succinate plus biphenyl, contains an enzyme system that oxidizes benzo[
a
]pyrene and benzo[
a
]anthracene to mixtures of vicinal dihydrodiols. The major dihydrodiol formed from benzo[
a
]pyrene was identified as
cis
-9,10-dihydroxy-9,10-dihydrobenzo[
a
]pyrene by comparison with a synthetic sample. Benzo[
a
]anthracene was metabolized to four dihydrodiols, the major isomer being
cis
-1,2-dihydroxy-1,2-dihydrobenzo[
a
]anthracene.
Glomerular Epithelium: Structural Alterations Induced by Polycations
Authors: Seiler M. W. , Venkatachalam M. A. , Cotran R. S.
Published: October 2006

Perfusion of rat kidneys with the polycation protamine sulfate caused glomerular epithelial alterations resembling those observed in human and experimental nephrotic states. The changes included swelling, blunting, and flattening of epithelial foot processes, were accompanied by decreased stainability of glomerular anionic sites, and were largely reversed by subsequent perfusion with the polyanion heparin.
Compositional Trends in Rock-Forming Elements of Comet Halley Dust
Authors: Fomenkova M. N. , Kerridge J. F. , Marti K. , McFadden L.-A.
Published: October 2006

The VEGA 1 and 2 spacecraft flew by comet P/Halley in 1986 carrying, among other instruments, two mass spectrometers to measure the elemental composition of dust particles emitted from the comet. Most particles seem to be a mixture of silicates of variable magnesium-iron composition and organic matter. Comprehensive study of data and consideration of the mass of dust particles reveal cometary grains of "unusual" composition: magnesium-rich and iron-rich particles. Magnesium-rich particles are most likely magnesium carbonates, which could not have formed under conditions of equilibrium condensation but rather require formation by aqueous alteration. The composition of the iron-rich particles can also be related to secondary processes in the comet.
Neurospora
Circadian Rhythms in Space: a Reexamination of the Endogenous-Exogenous Question
Authors: Sulzman Frank M. , Ellman David , Fuller Charles A. , Moore-Ede Martin C. , Wassmer Gary
Published: October 2006

To test the functioning of circadian rhythms removed from periodicities of the earth's 24-hour rotation, the conidiation rhythm of the fungus
Neurospora crassa
was monitored in constant darkness during spaceflight. The free-running period of the rhythm was the same in space as on the earth, but there was a marked reduction in the clarity of the rhythm, and apparent arrhythmicity in some tubes. At the current stage of analysis of our results there is insufficient evidence to determine whether the effect seen in space was related to removal from 24-hour periodicities and whether the circadian timekeeping mechanism, or merely its expression, was affected.
Bottle-Nosed Dolphin: Double-Slit Pupil Yields Equivalent Aerial and Underwater Diurnal Acuity
Authors: Herman Louis M. , Peacock Michael F. , Yunker Michael P. , Madsen Carolyn J.
Published: October 2006

In bright daylight, and at best viewing distances, the bottlenosed dolphin resolves visual gratings approximately equally well in air and in water. Aerial resolution improves with increased viewing distance, while underwater resolution improves with decreased viewing distance. The double-slit pupil overcomes the gross myopia in air measured by ophthalmoscope and produces the indicated effects of viewing distance.
Speech Perception by the Chinchilla: Voiced-Voiceless Distinction in Alveolar Plosive Consonants
Authors: Kuhl Patricia K. , Miller James D.
Published: October 2006

Four chinchillas were trained to respond differently to /t/ and /d/ consonant-vowel syllables produced by four talkers in three vowel contexts. This training generalized to novel instances, including synthetically produced /da/ and /ta/ (voice-onset times of 0 and +80 milliseconds, respectively). In a second experiment, synthetic stimuli with voice-onset times between 0 and +80 milliseconds were presented for identification. The form of the labeling functions and the "phonetic boundaries" for chinchillas and English-speaking adults were similar.
Pregnancy in Cactus Mice: Effects of Prolonged Copulation
Authors: Dewsbury Donald A. , Estep Daniel Q.
Published: October 2006

The postejaculatory copulations of cactus mice are demonstrated to function in facilitating neuroendocrine responses necessary for pregnancy. Whereas estrous cycles were altered after just 10 percent of the tests terminated after one ejaculatory series, females became either pregnant or pseudopregnant after 80 percent of tests continued at least to sexual satiety (30 minutes with no copulations).
α-Lactalbumin Production in Human Mammary Carcinoma
Authors: Rose Herbert N. , McGrath Charles M.
Published: October 2006

α-Lactalbumin was isolated from mature human milk and utilized as an immunogen in rabbits. A radioimmunoassay was developed that was capable of detecting nanogram quantities of the antigen. α-Lactalbumin synthesis was detected in human breast cancer cells (MCF-7) cultivated as a continuous cell line in vitro. Other human carcinoma epithelial cell lines (throat and cervix) failed to react in this assay. The ability to synthesize α-lactalbumin by breast carcinoma cells appeared to be independent of the addition of prolactin to the culture medium.
Prostaglandins in Rabbit Blastocysts
Authors: Dickmann Z. , Spilman C. H.
Published: October 2006

Rabbit blastocysts recovered at 144 hours post coitum contained the prostaglandins F and E-A. We suggest that one or more of these prostaglandins act as mediators in blastocyst steroidogenesis. (In another study we have demonstrated steroidogenesis in rabbit blastocysts).
Brown Pelicans: Improved Reproduction Off the Southern California Coast
Authors: Anderson Daniel W. , Jehl Joseph R. , Risebrough Robert W. , Woods Leon A. , Deweese Lawrence R. , Edgecomb William G.
Published: October 2006

Although still about 30 percent too low for population stability, productivity of California brown pelicans at their two northern colonies has improved significantly since 1971. Numbers of adults breeding probably reflect food supplies and recruitment from more successful colonies to the south, but improving fledging rates (up to 0.9 young per nest in 1974) reflect better egg survival and improving eggshell condition, with declining DDE contamination in anchovies, their major food source.
Reversal of Acetylcholine Potentials in Eel Electroplaque
Authors: Lassignal Nancy L. , Martin A. R.
Published: October 2006

Although the eel electroplaque is a major source of purified acetylcholine (ACh) receptor, the electrophysiological properties of the receptor have not been studied in detail. In particular, the reversal potential for the action of ACh on the postsynaptic membrane has not been measured directly. In order to obtain the reversal potential, ACh was applied iontophoretically from a micropipette onto the innervated membrane. The resulting depolarization (ACh potential) decreased in amplitude as the cell was depolarized, reached zero at a reversal potential of about -4 millivolts, and then reversed in sign as the inside of the cell was made increasingly more positive. The relation between ACh potential amplitude and membrane potential was nonlinear because of a decrease with depolarization of the peak conductance change produced by the drug.
Demonstration of Kinetoplast DNA in Dyskinetoplastic Strains of
Trypanosoma equiperdum
Authors: Hajduk Stephen L.
Published: October 2006

4,6-Diamidino-2-phenylindole (DAPI) forms a highly fluorescent complex with DNA which allows detection of mitochondrial DNA (K-DNA) in normal and dyskinetoplastic strains of
Trypanosoma equiperdum
. The K-DNA DAPI complexes in the dyskinetoplastic cells, cells lacking detectable K-DNA by other cytochemical methods, are not restricted to a single region of the organism as in the normal strain, but are seen as a row of particles. These observations support the hypothesis that the K-DNA is retained in dyskinetoplastic cells.
Sex Pheromone Specificity in the Pine Sawflies: Interchange of Acid Moieties in an Ester
Authors: Jewett Douglas M. , Matsumura Fumio , Coppel Harry C.
Published: October 2006

3,7-Dimethylpentadecan-2-ol was identified as the free alcohol in three species from two genera of pine sawflies (Hymenoptera: Diprionidae). In
Neodiprion lecontei
and
Neodiprion sertifer
the acetate of this alcohol is the major component of their sex attractant; in
Diprion similis
it is the propionate. By examining the responses of the male antennae of several species of
Neodiprion
through the electroantennographic technique, it was determined that four species responded to the acetate and six to the propionate.
Stable and Plastic Unit Discharge Patterns During Behavioral Generalization
Authors: Ramos Alexis , Schwartz Eric L. , John E. Roy
Published: October 2006

A movable microelectrode was implanted in adult cats trained to respond differentially to two different frequencies of light flicker. Unit responses were recorded along cortical and thalamic trajectories. The late components of the poststimulus response of 29 percent of the cells examined showed statistically significant differences when data from different behavioral outcomes to the same neutral generalization stimulus were compared.
Inherited Retinal Dystrophy: Primary Defect in Pigment Epithelium Determined with Experimental Rat Chimeras
Authors: Mullen Richard J. , LaVail Matthew M.
Published: October 2006

Chimeric rats were produced by the aggregation of embryos of the pink-eyed, retinal dystrophic RCS strain with those of pigmented, normal rats. In the mosaic eyes, patches of neural retina with abnormal and degenerated photoreceptors were present only opposite patches of nonpigmented, mutant pigment epithelium. This indicates that the retinal dystrophy gene acts in the pigment epithelial cell rather than in the photoreceptor cell.
Stimulant-Related State-Dependent Learning in Hyperactive Children
Authors: Swanson James M. , Kinsbourne Marcel
Published: October 2006

Hyperactive and nonhyperactive children performed a learning task in two states, while being treated with stimulant medication (methylphenidate) and while taking a placebo, and were tested for retention of each class of learned material in both states. Symmetrical state-dependent learning was demonstrated in the hyperactive group but not in the nonhyperactive group. The state-dependent effect was contingent on the presence of drug-induced facilitation during initial learning. This is apparently the first report on record of state-dependent learning with a drug agent that facilitates rather than impairs performance of human subjects.
Effect of Post Partum Separation of Mother and Kid on Maternal Care in the Domestic Goat
Authors: Hersher Leonard , Moore A. Ulric , Richmond Julius B.
Published: October 2006

Twenty-four goat mothers were separated from their newborn kids for 1 hour immediately following birth. Two months later these mothers were observed to nurse their own kids less and alien kids more than nonseparated mothers. Separation of mother and young in half the flock also resulted in abnormal "rejecting" behavior in some nonseparated mothers.
Biochemistry of Nitric Oxide and Its Redox-Activated Forms
Authors: Stamler Jonathan S. , Singel David J. , Loscalzo Joseph
Published: October 2006

Nitric oxide (NO
⋅
), a potentially toxic molecule, has been implicated in a wide range of biological functions. Details of its biochemistry, however, remain poorly understood. The broader chemistry of nitrogen monoxide (NO) involves a redox array of species with distinctive properties and reactivities: NO
+
(nitrosonium), NO
⋅
, and NO
-
(nitroxyl anion). The integration of this chemistry with current perspectives of NO biology illuminates many aspects of NO biochemistry, including the enzymatic mechanism of synthesis, the mode of transport and targeting in biological systems, the means by which its toxicity is mitigated, and the function-regulating interaction with target proteins.
Nonidentity of Fetuin and Protein Growth (Flattening) Factor
Authors: Lieberman Irving , Lamy Francois , Ove Peter
Published: October 2006

Fetuin, a fetal calf serum glycoprotein, appeared to possess activity with cultured mammalian cells similar to that of a protein growth factor partially purified from adult bovine and human sera. Column chromatography, however, yielded highly purified but inactive fetuin. These results leave open questions regarding the role of this interesting and readily purified protein.
Centrifugal Arousal in the Olfactory Bulb
Authors: Lavín A. , Alcocer-Cuarón C. , Hernandez-Peón R.
Published: October 2006

The electrical activity of the olfactory bulb was recorded in awake, unrestrained cats with electrodes permanently implanted. It was found that any kind of sensory stimulation producing alertness or arousal brought about the appearance of bursts of rhythmic activity, the magnitude of which was related to the degree of alertness of the cat.
Structural Correlation between Esterase and Protease Activities of Trypsin
Authors: Augenstine Leroy
Published: October 2006

It is tentatively concluded from ultraviolet and x-ray studies that the two tryptic activities are mediated by overlapping "enzymatic sites." Crucial to this conclusion were studies of the factors which can modify the measured inactivation rates. The data are interpreted in the light of postulated mechanisms of inactivation.
An Auxin-like Action of Coumarin
Authors: Neumann J.
Published: October 2006

Coumarin, usually regarded as an inhibitor of growth processes in plants, markedly stimulated the elongation of excised segments of
Helianthus
hypocotyls. Substitution in the molecule of hydroxy-, methyl-, or chloro-groups, in the neighborhood of the unsaturated bond in the lactone ring, markedly altered the growth-promoting activity.
Biophysical Approach toward Tumor Regression in Mice
Authors: Humphrey Carroll E. , Seal E. H.
Published: October 2006

An external electrical source of low magnitude was used in a series of experiments to alter inherent tumor potentials in mice. While no significant increase of tumor growth was noted in the acceleration group, total tumor regressions were obtained in the inhibition group. Preliminary studies with leukemia did not yield significant results.
Dispersal of Fresh-Water Algae by Migratory Water Birds
Authors: Proctor Vernon W.
Published: October 2006

Many migratory water birds killed in Texas and Oklahoma contained viable fresh-water algae in the lower digestive tracts. Such birds are thought to play a significant role in the long-range dispersal of certain algae, particularly those species easily killed by desiccation.
Mummified Seal Carcasses in the McMurdo Sound Region, Antarctica
Authors: Péwé Troy L. , Rivard Norman R. , Llano George A.
Published: October 2006

Information was collected on 90 mummified carcasses of the "crabeater" seal in the ice-free areas of the McMurdo Sound region, Antarctica. The carcasses range from relatively well-preserved bodies to merely old, twisted, wind-dissected fragments of tissue. They are hard and dry and lie on the surface of the ground, mostly in valley bottoms. The arid, cold climate is ideal for retarding organic decay. One carcass was dated by radiocarbon analysis and found to be between 1600 and 2600 years old.
Continuity of Mid-Oceanic Ridge and Rift Valley in the Southwestern Indian Ocean Confirmed
Authors: Ewing Maurice , Heezen Bruce C.
Published: October 2006

The existence of a continuous, rifted, mid-oceanic ridge in the southwestern Indian Ocean, previously predicted by us, has been confirmed by soundings taken by the research vessel
Vema
during the expedition now in progress.
Body-Wall Muscle Formation in
Caenorhabditis elegans
Embryos that Lack the MyoD Homolog
hlh-1
Authors: Chen Lihsia , Krause Michael , Draper Bruce , Weintraub Harold , Fire Andrew
Published: October 2006

The myoD family of DNA binding proteins has been implicated in the control of myogenesis in a variety of organisms. Searches for homologs in the nematode
Caenorhabditis elegans
yielded only one gene, designated
hlh-1
, expressed in body-wall muscle cells and their precursors. To assess the role of
hlh-1
in
C. elegans
myogenesis, genetic deficiencies spanning the
hlh-1
locus were isolated after gamma irradiation. Embryos homozygous for these deficiencies exhibited extensive body-wall muscle differentiation, including expression of several characteristic myofilament proteins and weak contracile behavior. Thus, zygotic
hlh-1
expression was not required for body-wall muscle precursors to adopt muscle cell fates.
Sound Production by the Satinfin Shiner,
Notropis analostanus
, and Related Fishes
Authors: Winn Howard E. , Stout John F.
Published: October 2006

Several sounds are produced by minnows. Only one is not of purely mechanical origin, and it is classed as a "biological" sound. This sound is variously produced by males when fighting and chasing as well as during courtship. Females emit a similar sound. Testosterone injections and elevated temperatures result in an increased rate of biological sound emission.
Two Forms of Chlorophyll
a
in vivo with Distinct Photochemical Functions
Authors: Govindjee  , Rabinowitch Eugene
Published: October 2006

Action spectra of the Emerson effect in
Chlorella
and
Navicula
reveal peaks at 670 mμ, in addition to those at 650 mμ (
Chlorella
) and 630 mμ (
Navicula
) attributable to chlorophylls
b
and
c
. Thus, excitation of chlorophyll
a
form "chlorophyll
a
670" can supplement, in these algae, the excitation of the form "chlorophyll
a
680-700." The effect of the auxiliary pigments in these algae may be mediated by energy transfer to "chlorophyll
a
670."
Staining of Skin with Dihydroxyacetone
Authors: Wittgenstein Eva , Berry Helen K.
Published: October 2006

The reaction of skin with dihydroxyacetone to produce a brown "artificial tan" appears to proceed through combination with free amino groups in skin proteins, and particularly by combination of dihydroxyacetone with the free guanido group in arginine.
Phosphorylation-Independent Modulation of L-Type Calcium Channels by Magnesium-Nucleotide Complexes
Authors: O'Rourke Brian , Backx Peter H. , Marban Eduardo
Published: October 2006

Free magnesium ions and magnesium-nucleotide complexes can exert opposite effects on many fundamental cellular processes. Although increases in the intracellular concentration of magnesium ions inhibit the L-type calcium current in heart cells, magnesium-adenosine triphosphate complexes (MgATP) would be expected to increase the current by promoting channel phosphorylation. Rapid increases in the intracellular concentration of MgATP induced by flash photolysis of caged magnesium or caged ATP resulted in enhanced calcium current. The increase in calcium current was not prevented by blocking phosphorylation, revealing a previously unrecognized direct regulatory action of the magnesium-nucleotide complex.
Role of βγ Subunits of G Proteins in Targeting the β-Adrenergic Receptor Kinase to Membrane-Bound Receptors
Authors: Pitcher Julie A. , Inglese James , Higgins Joyce B. , Arriza Jeffery L. , Casey Patrick J. , Kim Chong , Benovic Jeffery L. , Kwatra Madan M. , Caron Marc G. , Lefkowitz Robert J.
Published: October 2006

The rate and extent of the agonist-dependent phosphorylation of β
2
-adrenergic receptors and rhodopsin by β-adrenergic receptor kinase (βARK) are markedly enhanced on addition of G protein βγ subunits. With a model peptide substrate it was demonstrated that direct activation of the kinase could not account for this effect. G protein βγ subunits were shown to interact directly with the COOH-terminal region of βARK, and formation of this βARK-βγ complex resulted in receptor-facilitated membrane localization of the enzyme. The βγ subunits of transducin were less effective at both enhancing the rate of receptor phosphorylation and binding to the COOH-terminus of βARK, suggesting that the enzyme preferentially binds specific βγ complexes. The βγ-mediated membrane localization of βARK serves to intimately link receptor activation to βARK-mediated desensitization.
Toxoplasma from the Eggs of the Domestic Fowl (
Gallus gallus
)
Authors: Pande P. G. , Shukla R. R. , Sekariah P. C.
Published: October 2006

Toxoplasmata of varying grades of virulence were isolated from eggs laid by clinically asymptomatic hens and from their internal organs. The strains so recovered were identified as
Toxoplasma gondii
by morphological, serological, cultural, and pathogenic criteria. These findings strongly suggest that toxoplasmosis may be contracted through the eating of raw or undercooked infected eggs.
Does the Male Stimulate Oestrogen Secretion in Female Canaries?
Authors: Warren Roslyn P. , Hinde R. A.
Published: October 2006

Female Border canaries treated with oestrogen during the nonbreeding season may build nests, regardless of winter lighting, temperature, and absence of partner. Incubation may follow completion of the nest although ovulation is suppressed. Reactions obtained in the breeding season suggest that the male does not initiate but accelerates oestrogen production through the stimulation he provides.
Effects of Plant Nutrients on Uptake of Radiostrontium by Thatcher Wheat
Authors: Lee C. C.
Published: October 2006

The effects of various dosages of ammonium dihydrogen phosphate, monocalcium phosphate, calcium chloride, and potassium chloride on the uptake of radiostrontium by Thatcher wheat grown in Saskatchewan Oxbow loam soil containing strontium-85 were studied. Monocalcium phosphate at a dose level of about 600 lb/acre of soil effected a statistically significant reduction of strontium-85 uptake in each of the four plant fractions of grain, chaff, stem, and leaf. At the very reasonable dosage of about 60 lb/acre, monocalcium phosphate gave a statistically significant reduction in strontium-85 uptake in the grain and chaff.
Synthesis of Bacterial Cellulose from Labeled Precursor
Authors: Khan A. W. , Colvin J. R.
Published: October 2006

The isolation and purification of an immediate precursor of bacterial cellulose was confirmed with glucose randomly labeled with carbon-14. The glucose appears to be bound within the cell to a lipid, is carried across the bacterial cell wall, and is incorporated enzymatically into cellulose extracellularly.
Transport of Proteins Across the Endoplasmic Reticulum Membrane
Authors: Rapoport Tom A.
Published: October 2006

The biosynthesis of many eukaryotic proteins requires their transport across the endoplasmic reticulum (ER) membrane. The process can be divided into two phases: (i) a targeting cycle, during which, by virtue of their signal sequences, nascent polypeptides are directed to translocation sites in the ER and (ii) the actual transfer of proteins across the membrane. The first phase has been well characterized, whereas the latter until recently was completely unresolved. Key components of the translocation apparatus have now been identified and it seems likely that they form a protein-conducting channel in the ER membrane. The transport process is similar to the process of protein export in bacteria.
Lead-210 in Natural Waters
Authors: Rama  , Koide Minoru , Goldberg Edward D.
Published: October 2006

The distribution of lead-210 which enters the oceans subsequent to its production in the atmosphere by radon-222 decay, shows an increase with depth in sea water. By use of a simplified two-layer model of the ocean, a residence time of lead in the upper mixed layer of less than 2 years is derived. It is suggested that the marine biosphere is responsible for the conveyance of lead from surface to deeper waters. The distribution of lead-210 in the Colorado River indicated a rapid removal along the path from its origin in the feed waters to the reservoir at Lake Mead.
Patination of Cultural Flints
Authors: Hurst Vernon J. , Kelly A. R.
Published: October 2006

All flints containing unstable impurities are susceptible to patination. The rate of patination varies with many factors: (i) the texture and microstructure of the flint; (ii) its permeability; (iii) the kind, proportion, and distribution of impurities; and (iv) environmental factors, such as temperature and soil chemistry. The thickness of the patina varies also with time.

Two contrasting types of patina can develop: a chalky white patina and a ferruginous brown patina. Both types are observable primarily as a color change, and study of these types is facilitated by a clear understanding of the causes of color in flint.

The color of most flints is the result of repeated refraction and reflection of light at numerous intergranular surfaces, whereby part of the light is internally absorbed and part is reflected back to the observer. The ratio of reflected to absorbed light governs the lightness of the color, or its value. The preferential absorption of certain wavelengths by natural pigments (such as iron oxide and hydrous iron oxide) disseminated through the flint determine the hue of the color.

The color changes produced during patination relate to changes in texture and impurity content occasioned by the attack of weathering agents on impurities in the flint. The creation of voids by the dissolution and leaching of carbonates, the loosening of quartz crystallites, and the dispersal of clays all modify the reflectivity of the flint. Chemical changes involving the pigments, their dispersal along intergranular surfaces, or removal by leaching modify both reflectivity and capacity to preferentially absorb.

Attempts to correlate patina thickness with age, and thus to use flint patinae chronometrically, have proven unsatisfactory because other factors, whose importance in some cases exceeds that of age, have not been taken into account. The texture and microstructure of flint, its permeability, and the kind, proportion, and distribution of impurities can be evaluated by regular petrographic techniques. Environmental factors can be assumed constant for artifacts from the same types of soil in a given climatic region. Only after allowances have been made for these additional variables does the age-dependence of flint patination become clear.
Oviparous Hermaphroditic Fish with Internal Self-Fertilization
Authors: Harrington Robert W.
Published: October 2006

Adults of
Rivulus marmoratus
(Cyprinodontidae) contained eggs when dissected or laid eggs when kept alive. They invariably oviposited solo, emitting eggs in various developmental stages. Both juvenescent and senescent fish have functional ovotestes. Progeny (F
3
) were obtained via a selfed great grandparent, grandparent, and parent, the last two in isolation
ab ovo
.
LCMV-Specific, Class II-Restricted Cytotoxic T Cells in β2-Microglobulin-Deficient Mice
Authors: Muller Daniel , Koller Beverly H. , Whitton J. Lindsay , LaPan Katherine E. , Brigman Kristen K. , Frelinger Jeffrey A.
Published: October 2006

Intracranial infection of normal mice with lymphocytic choriomeningitis virus (LCMV) causes meningitis and death mediated by CD8
+
major histocompatibility complex (MHC) class I-restricted cytotoxic T lymphocytes (CTLs). β
2
-Microglobulin-deficient mice (β
2
M
-/-
) do not express functional MHC class I proteins and do not produce significant numbers of CD8
+
T cells. When β
2
M
-/-
mice were infected with LCMV, many died from LCMV disease and produced a specific response to LCMV mediated by CD4
+
CTLs that were class II-restricted. In these mice, CD4
+
CTLs may compensate for the lack of CD8
+
CTLs.
Identical "Feeding" and "Rewarding" Systems in the Lateral Hypothalamus of Rats
Authors: Margules D. L. , Olds J.
Published: October 2006

Electrodes were implanted in the lateral hypothalamic feeding system; animals were subjected to both feeding and motivational tests. All animals that demonstrated stimulus-bound feeding behavior also showed high self-stimulation rates. As it was impossible to produce the feeding response without simultaneously producing the rewarding effect of hypothalamic stimulation, it was concluded that the feeding system of the lateral hypothalamus is one among a larger group of places where stimulation causes primary rewarding effects. With electrodes in these same areas, food deprivation often caused a major increment in the self-stimulation rate.
Strain and Sex Differences in Serum Cholesterol Levels of Mice
Authors: Bruell Jan H. , Daroczy Alex F. , Hellerstein Herman K.
Published: October 2006

Five inbred strains of mice differed significantly in serum cholesterol level. Cholesterol levels ranged from 128 mg/100 ml in C57B1/6 mice to 208 mg/100 ml in C3H mice. Cholesterol level was significantly higher in males than in females. The cholesterol level of 2-month-old mice did not differ from that of 1-year-old mice.
Preservation of Old, Waterlogged Wood by Treatment with Polyethylene Glycol
Authors: Seborg Ray M. , Inverarity Robert Bruce
Published: October 2006

The excessive cracking and distortion that old waterlogged wood undergoes when it is dried can be substantially reduced by treating the wood with polyethylene glycol. The process was used to dry 200-year-old waterlogged wood boats recently raised from Lake George, New York.
Formation of Carbon Monoxide during Seed Germination and Seedling Growth
Authors: Siegel S. M. , Renwick G. , Rosen L. A.
Published: October 2006

Carbon monoxide was formed during the growth of cucumber seedlings in the dark in atmospheres containing 5 percent oxygen or less, but not by aerobic seedlings. The highest level recorded was 6000 ppm. Carbon monoxide was also formed by
Euphorbia
. Germinating seeds of rye, cucumber, and other species also produced carbon monoxide at levels of 10 to 25 ppm.
Lunar Synodical Period and Widespread Precipitation
Authors: Bradley Donald A. , Woodbury Max A. , Brier Glenn W.
Published: October 2006

Precipitation activity over broad areas appears to be closely associated with the monthly lunisolar cycle. Indexes of precipitation in the continental United States over a continuous 50-year period, and 91-year daily histories of individual stations, reveal that heavy rains occur most frequently in the first and third weeks of the synodical month.
Sorbitol Translocation in Apple
Authors: Webb Kenneth L. , Burley J. William A.
Published: October 2006

A report of glucose translocation, an apparent exception to the hypothesis that sucrose is the major carbohydrate translocated in plants, was investigated. Carbon-14 studies of the carbohydrates in the bark of apple suggest that rather than glucose the sugar alcohol, sorbitol, in addition to sucrose, is a principal compound translocated in this species.
Continuous Culture of a Melanotic Cell Line from the Golden Hamster
Authors: Moore George E. , Lehner Donald F. , Kikuchi Yasumoto , Ann Less Louise
Published: October 2006

A melanotic cell line derived from a malignant melanoma of the golden hamster has retained its ability to produce melanin in vitro. This cell line provides an opportunity for studying the synthesis of melanin under various controlled conditions. The modal chromosome number in this cell line is 68.
Migration of Proteins along the Axons of the Sciatic Nerve
Authors: Droz B. , Leblond C. P.
Published: October 2006

Soon after single or repetitive injections of leucine-H
3
in rats, an intense radioautographic reaction was seen over the nerve cell bodies, while the axons of the myelinated fibers of the sciatic nerve were insignificantly labeled. Later, however, these axons showed strong radioactivity, which at 4 days was located in a proximal and at 16 days in a distal region of the nerve. It was concluded that the protein synthesized in the nerve cell bodies of the sciatic nerve had migrated along its axons.
Overlapping but Nonidentical Binding Sites on CD2 for CD58 and a Second Ligand CD59
Authors: Hahn William C. , Menu Elisabeth , Bothwell Alfred L. M. , Sims Peter J. , Bierer Barbara E.
Published: October 2006

The interaction of the T cell glycoprotein CD2 with one ligand, CD58, contributes to T cell function. We have identified CD59, a glycoprotein with complement-inhibitory function, as a second physiological ligand for CD2. Antibodies to CD59 inhibit CD2-dependent T cell activation in murine T cell hybridomas expressing human CD2. In an in vitro binding assay with purified CD58 and CD59, CD2
+
cells bind not only immobilized CD58 but also CD59. With two complementary approaches, it was demonstrated that the binding sites on CD2 for CD58 and CD59 are overlapping but nonidentical. These observations suggest that direct interactions between CD2 and both CD58 and CD59 contribute to T cell activation and adhesion.
Tritium and Helium-3 in Solar Flares and Loss of Helium from the Earth's Atmosphere
Authors: Flamm E. , Lingenfelter R. E. , MacDonald Gordon J. F. , Libby W. F.
Published: October 2006

Analysis of the data gathered by the Discoverer XVII satellite on the constituents of solar flares leads to results that have broad implications in geophysics and solar physics.
Inter-tissue Complementation: A Simple Technique for Direct Analysis of Gene-Action Sequence
Authors: Reddy G. M. , Coe E. H.
Published: October 2006

Sequence of gene action can be determined from unidirectional complementary interactions between synthetically active but genetically blocked tissues. A linear sequence of gene action has been constructed for anthocyanin synthesis in maize by this approach. This technique probably can be applied to other systems and organisms that have the requisite circumstances.
Fission Product Radioactivity in the North Polar Stratosphere
Authors: Gustafson P. F. , Keener R. B. , McGinnis G. A. , Soller R. A.
Published: October 2006

Balloon-borne gamma-ray detection equipment flown from Thule, Greenland, during April 1962, indicated that there was considerable radioactivity above 70,000 feet. Gamma-ray spectra obtained indicated the source of much of the activity to be the Soviet nuclear tests in late 1961.
Corticospinal Connections: Postnatal Development in the Rhesus Monkey
Authors: Kuypers Henricus G. J. M.
Published: October 2006

The spinal distribution of the corticospinal fibers was studied experimentally in infant rhesus monkeys (
Macaca mulatta
) by means of the Nauta-Gygax silver impregnation technique. The findings suggest that the bulk of the direct cortico-motoneuronal connections in the rhesus monkey are established postnatally, during at least the first 8 months of life.
Chemiluminescence of Firefly Luciferin without Enzyme
Authors: Seliger H. H. , McElroy W. D.
Published: October 2006

We have been able to produce chemiluminescence in firefly luciferin without utilizing the enzyme luciferase. Following the analogous mechanism of the chemiluminescence of luminol in the organic solvent dimethyl sulfoxide, we have prepared synthetically the methyl ester of luciferin, the phosphate ester of luciferin and luciferyl adenylate by condensation in dimethyl sulfoxide with Khorana's reagent, dicyclohexylcarbodiimide and diazomethane, phosphoric acid, and adenylic acid respectively. These compounds in dimethyl sulfoxide in the presence of base emit a bright chemiluminescence. Like in vitro enzymatic bioluminescence, the luciferyl adenylate chemiluminescence emission spectrum is dependent upon
p
H.
Correspondence between Stevens' Terminal Brightness Function and the Discriminability Law
Authors: Green Elmer E.
Published: October 2006

Stevens' terminal brightness function, an adaptation curve derived from power law data, closely agrees with Troland's just-noticeable-difference (jnd) summation for brightness. The power law itself describes sensation magnitude
before
adaptation to a test stimulus, whereas the Fechnerian discriminability law describes sensation magnitude
after
adaptation. This suggests their synthesis in a more general psychophysical equation.
Formation and Activation of a Cyclin E-cdk2 Complex During the G
1
Phase of the Human Cell Cycle
Authors: Koff Andrew , Giordano Antonio , Desai Dipty , Yamashita Katsumi , Harper J. Wade , Elledge Stephen , Nishimoto Takaharu , Morgan David O. , Franza B. Robert , Roberts James M.
Published: October 2006

Human cyclin E, originally identified on the basis of its ability to function as a G
1
cyclin in budding yeast, associated with a cell cycle-regulated protein kinase in human cells. The cyclin E-associated kinase activity peaked during G
1
, before the appearance of cyclin A, and was diminished during exit from the cell cycle after differentiation or serum withdrawal. The major cyclin E-associated kinase in human cells was Cdk2 (cyclin-dependent kinase 2). The abundance of the cyclin E protein and the cyclin E-Cdk2 complex was maximal in G
1
cells. These results provide further evidence that in all eukaryotes assembly of a cyclin-Cdk complex is an important step in the biochemical pathway that controls cell proliferation during G
1
.