bluuebunny/crossref_metadata_2025 huggingface dataset:
Detection of HIV-1 DNA and Messenger RNA in Individual Cells by PCR-Driven in Situ Hybridization and Flow Cytometry
Authors: Patterson Bruce K. , Till Michele , Otto Patricia , Goolsby Charles , Furtado Manohar R. , McBride Lincoln J. , Wolinsky Steven M.
Published: October 2006

Human immunodeficiency virus type-1 (HIV-1) DNA and messenger RNA sequences in both cell lines and blood obtained directly from HIV-1-infected patients were amplified by polymerase chain reaction and hybridized to fluorescein-labeled probes in situ, and the individually labeled cells were analyzed by flow cytometry. After flow cytometric analysis, heterogeneous cell populations were reproducibly resolved into HIV-1-positive and -negative distributions. Fluorescence microscopy showed that the cellular morphology was preserved and intracellular localization of amplified product DNA was maintained. Retention of nonspecific probe was not observed. Analysis of proviral DNA and viral messenger RNA in cells in the blood of HIV-1-infected patients showed that the HIV-1 genome persists in a large reservoir of latently infected cells. With the use of this technique it is now possible to detect single-copy DNA or low-abundance messenger RNA rapidly and reproducibly in a minor subpopulation of cells in suspension at single-cell resolution and to sort those cells for further characterization.
Generation of Allospecific Natural Killer Cells by Stimulation Across a Polymorphism of HLA-C
Authors: Colonna Marco , Brooks Edward G. , Falco Michela , Ferrara Giovan Battista , Strominger Jack L.
Published: October 2006

The cytotoxicity of human natural killer (NK) cells is modulated by the major histocompatibility complex human leukocyte antigen (HLA)-C molecules on the surface of the target cell. Alloreactive NK cells specific for the NK-1 alloantigen could be reproducibly generated from individuals that were homozygous for HLA-C with asparagine at residue 77 and lysine at residue 80 [HLA-C(Asn
77
, Lys
80
)] by stimulation with target cells that were homozygous for HLA-C(Ser
77
, Asn
80
); the reciprocal stimulation yielded NK cells specific for the NK-2 alloantigen. However, neither homozygous target cell stimulated the generation of alloreactive NK cells from heterozygous individuals. Thus, these data reveal an unanticipated difference between human NK alloreactivity defined by this system and murine "hybrid resistance."
GDNF: a Glial Cell Line-Derived Neurotrophic Factor for Midbrain Dopaminergic Neurons
Authors: Lin Leu-Fen H. , Doherty Daniel H. , Lile Jack D. , Bektesh Susan , Collins Frank
Published: October 2006

A potent neurotrophic factor that enhances survival of midbrain dopaminergic neurons was purified and cloned. Glial cell line-derived neurotrophic factor (GDNF) is a glycosylated, disulfide-bonded homodimer that is a distantly related member of the transforming growth factor-β superfamily. In embryonic midbrain cultures, recombinant human GDNF promoted the survival and morphological differentiation of dopaminergic neurons and increased their high-affinity dopamine uptake. These effects were relatively specific; GDNF did not increase total neuron or astrocyte numbers nor did it increase transmitter uptake by γ-aminobutyric-containing and serotonergic neurons. GDNF may have utility in the treatment of Parkinson's disease, which is marked by progressive degeneration of midbrain dopaminergic neurons.
Structural Basis of Amino Acid α Helix Propensity
Authors: Blaber Michael , Zhang Xue-jun , Matthews Brian W.
Published: October 2006

The propensity of an amino acid to form an α helix in a protein was determined by multiple amino substitutions at positions 44 and 131 in T4 lysozyme. These positions are solvent-exposed sites within the α helices that comprise, respectively, residues 39 to 50 and 126 to 134. Except for two acidic substitutions that may be involved in salt bridges, the changes in stability at the two sites agree well. The stability values also agree with those observed for corresponding amino acid substitutions in some model peptides. Thus, helix propensity values derived from model peptides can be applicable to proteins. Among the 20 naturally occurring amino acids, proline, glycine, and alanine each have a structurally unique feature that helps to explain their low or high helix propensities. For the remaining 17 amino acids, it appears that the side chain hydrophobic surface buried against the side of the helix contributes substantially to α helix propensity.
Proliferation of Human Smooth Muscle Cells Promoted by Lipoprotein(a)
Authors: Grainger David J. , Kirschenlohr Heide L. , Metcalfe James C. , Weissberg Peter L. , Wade David P. , Lawn Richard M.
Published: October 2006

Elevated blood concentrations of lipoprotein(a) [Lp(a)] and its constituent, apolipoprotein(a) [apo(a)], constitute a major risk factor for atherosclerosis, but their physiological activities remain obscure. Lp(a) and purified apo(a) stimulated the growth of human smooth muscle cells in culture. This effect resulted from inhibition of plasminogen activation, and consequently the activation by plasmin of latent transforming growth factor-β, which is an inhibitor of smooth muscle cell growth. Because smooth muscle proliferation is one of the hallmarks of atherosclerotic lesions, these results point to a plausible mechanism for the atherogenic activity of Lp(a).
Complexes of Ras⋅GTP with Raf-1 and Mitogen-Activated Protein Kinase Kinase
Authors: Moodie Shonna A. , Willumsen Berthe M. , Weber Michael J. , Wolfman Alan
Published: October 2006

The guanosine triphosphate (GTP)-binding protein Ras functions in regulating growth and differentiation; however, little is known about the protein interactions that bring about its biological activity. Wild-type Ras or mutant forms of Ras were covalently attached to an insoluble matrix and then used to examine the interaction of signaling proteins with Ras. Forms of Ras activated either by mutation (Gly12Val) or by binding of the GTP analog, guanylyl-imidodiphosphate (GMP-PNP) interacted specifically with Raf-1 whereas an effector domain mutant, Ile36Ala, failed to interact with Raf-1. Mitogen-activated protein kinase (MAP kinase) activity was only associated with activated forms of Ras. The specific interaction of activated Ras with active MAP kinase kinase (MAPKK) was confirmed by direct assays. Thus the forming of complexes containing MAPKK activity and Raf-1 protein are dependent upon the activity of Ras.
Elemental Sulfur: Accumulation in Different Species of Fungi
Authors: Pezet R. , Pont V.
Published: October 2006

Sulfur, in elemental form, is present in several fungi especially in self-inhibited and resting structures such as dormant spores and sclerotia. The possible importance of sulfur in fungal spore dormancy is discussed.
Trigeminal Substrates of Intracranial Self-Stimulation in the Brainstem
Authors: van der Kooy Derek , Phillips Anthony G.
Published: October 2006

Intracranial self-stimulation was elicited by electrodes located in the trigeminal motor nucleus of the rat. Rebound jaw movements were also elicited at positive self-stimulation placements, but control experiments revealed that the lever pressing was not a motor artifact. It is suggested that modulation of trigeminal motoneurons may serve as an important reinforcement mechanism in the brainstem.
Degradation and Detoxification of Canavanine by a Specialized Seed Predator
Authors: Rosenthal Gerald A. , Janzen Daniel H. , Dahlman D. L.
Published: October 2006

Larvae of the bruchid beetle
Caryedes brasiliensis
feed exclusively on seeds of the Neotropical legume
Dioclea megacarpa
, which contains 13 percent L-canavanine by dry weight. L-Canavanine, a nonprotein amino acid analog of L-arginine, exhibits potent insecticidal properties. Most of the seed nitrogen is sequestered in canavanine, and bruchid beetle larvae do not simply excrete this toxic compound. Instead, these larvae possess extraordinarily high urease activity, which facilitates the conversion of canavanine to ammonia through urea. In this way, canavanine is effectively detoxified and a supply of nitrogen for fixation into organic linkage is ensured.
Adequate Response of Plasma 1,25-Dihydroxyvitamin D to Parturition in Paretic (Milk Fever) Dairy Cows
Authors: Horst R. L. , Eisman J. A. , Jorgensen N. A. , DeLuca H. F.
Published: October 2006

The concentration of 1,25-dihydroxyvitamin D was measured by means of a radioactive receptor assay in the plasma of cows during the period immediately prior to, during, and following parturition. Nonparetic cows showed initially a slight decrease in plasma 1,25-dihydroxyvitamin D which was followed by a significant increase during parturition and 2 days postpartum. The highest concentration achieved in the control or nonparetic cows was 100 picograms per milliliter. In the paretic animals the plasma 1,25-dihydroxyvitamin D concentration increased sharply during the day preceding calving and reached a maximum of 200 picograms per milliliter at parturition. This level was maintained during the ensuing 2.5 days. These results demonstrate that parturient paresis cannot be the result of insufficient synthesis or secretion of 1,25-dihydroxyvitamin D.
The Cell Membrane Sodium Pump as a Mechanism for Increasing Thermogenesis During Cold Acclimation in Rats
Authors: Guernsey Duane L. , Stevens E. Don
Published: October 2006

Increased sodium pump activity is a major component of enhanced tissue thermogenesis in skeletal muscle, liver, and kidney of cold-acclimated rats. The sodium pump may play a major role in the thermoregulatory heat production during cold adaptation in mammals.
Visual Search in the Pigeon: Hunt and Peck Method
Authors: Blough Donald S.
Published: October 2006

Pigeons pecked at small forms displayed on an oscilloscope screen under computer control. The birds were required to find a small o amid varying numbers of x forms. A photocell glued to the bird's beak provided a signal to the computer when the beak approached a form, and the computer recorded the time and target of the response. As in some similar studies with human subjects, errors and reaction times increased with number of x forms displayed. The method appears promising for further studies of search and of other processes related to perception and information-processing in birds.
Growth Hormone: Species-Specific Stimulation of Erythropoiesis in Vitro
Authors: Golde David W. , Bersch Noelle , Li Choh Hao
Published: October 2006

The effects of purified bovine and human growth hormone were tested in vitro with murine and human bone marrow by means of granulocyte-monocyte and erythroid progenitor cloning techniques. Nanogram concentrations of the growth hormones potentiated erythropoietin-stimulated erythropoiesis, but not granulopoiesis, in a species-specific manner.
Binocular Differences in Cortical Receptive Fields of Kittens After Rotationally Disparate Binocular Experience
Authors: Shinkman Paul G. , Bruce Charles J.
Published: October 2006

Kittens were afforded visual experience only while wearing goggles fitted with prisms that rotated the inputs to the two eyes equally but in opposite directions about the visual axes (16° for experimental subjects, 0° for control subjects). Subsequently, receptive-field organization of the visual cortex was studied, special attention being given to the preferred orientations of binocular cells. For each group, the distribution of interocular differences in preferred orientation centered about the prism rotation experienced during early development. Thus, for moderate amounts of relative rotation, the development of interocular matching of orientation specificity in binocular cells of the visual cortex reflects the correspondence of early visual input between the two eyes.
New Genetic Marker in Human Parotid Saliva (Pm)
Authors: Ikemoto Shigenori , Minaguchi Kiyoshi , Suzuki Kazuo , Tomita Koichi
Published: October 2006

In 195 parotid saliva samples collected at random from a Japanese population, two phenotypes were observed by electrophoresis in acid-urea starch gels. The protein showing polymorphisms was detected in the middle zone between Pa and Pb, and was tentatively designated Pm. Inheritance was controlled by a dominant allele at an autosomal locus. The frequencies of the genes determining these phenotypes were, for the Japanese population studied, Pm
+
= .38 ± .03, Pm
-
= .62 ± .03.
The Development of Language-Like Communication Without a Language Model
Authors: Goldin-Meadow Susan , Feldman Heidi
Published: October 2006

Deaf children who are unable to acquire oral language naturally and who are not exposed to a standard manual language can spontaneously develop a structured sign system that has many of the properties of natural spoken language. This communication system appears to be largely the invention of the child himself rather than of the caretakers.
Metastasis Results from Preexisting Variant Cells Within a Malignant Tumor
Authors: Fidler Isaiah J. , Kripke Margaret L.
Published: October 2006

Clones derived in vitro from a parent culture of murine malignant melanoma cells varied greatly in their ability to produce metastatic colonies in the lungs upon intravenous inoculation into syngeneic mice. This suggests that the parent tumor is heterogeneous and that highly metastatic tumor cell variants preexist in the parental population.
Mental Set Alters Visibility of Moving Targets
Authors: Sekuler Robert , Ball Karlene
Published: October 2006

An observer's knowledge of a moving target's direction and velocity enhances detectability. In addition, knowledge of direction and velocity speeds an observer's reaction to the motion of a previously stationary target. Since rival, nonperceptual hypotheses can be ruled out, these effects represent a direct modulation of vision by mental set.
Gap Junctions: Their Presence and Necessity in Myometrium During Parturition
Authors: Garfield R. E. , Sims S. , Daniel E. E.
Published: October 2006

Thin sections of longitudinal and circular muscle of myometrium obtained from rats during pregnancy, at term, during delivery, and postpartum were quantitatively examined in the electron microscope. Gap junctions (low resistance pathways) were only present during or immediately prior to delivery and immediately postpartum. The absence of gap junctions during gestation may be necessary for maintenance of pregnancy, while their occurrence during parturition may lead to effective termination of pregnancy.
Interkingdom Fusion Between Human (HeLa) Cells and Tobacco Hybrid (GGLL) Protoplasts
Authors: Jones C. Weldon , Mastrangelo Iris A. , Smith Harold H. , Liu H. Z. , Meck Robert A.
Published: October 2006

The fusion of human HeLa cells with tobacco protoplasts has been accomplished with the use of polyethylene glycol. The sequence from heterocellular adherence to heterokaryon formation has been followed with light microscopy and confirmed by autoradiographs of heterokaryons containing unlabeled tobacco nuclei and tritium-labeled HeLa nuclei. The HeLa nucleus retained its integrity in the tobacco cytoplasm up to 6 days after fusion.
Nucleus Suprachiasmaticus: The Biological Clock in the Hamster?
Authors: Stetson Milton H. , Watson-Whitmyre Marcia
Published: October 2006

Destruction of the suprachiasmatic nuclei in the golden hamster by bilateral radiofrequency lesions abolishes three well-documented circadian rhythms—locomotor activity, estrous cyclicity, and photoperiodic photosensitivity. Entrainment of these rhythms by light cycles fails in lesioned hamsters; females become persistently estrous; in both sexes locomotor activity becomes sporadic, confined primarily to the light instead of darkness, and is totally arrhythmic when lesioned animals are exposed to continuous darkness; the photoperiodic gonadal response (gonadal regression induced by short day lengths) is abolished; lesioned animals remain reproductively mature irrespective of photoperiodic treatment.
Selective Brain Dopamine Depletion in Developing Rats: An Experimental Model of Minimal Brain Dysfunction
Authors: Shaywitz Bennett A. , Yager Robert D. , Klopper Jeffrey H.
Published: October 2006

Administration of 6-hydroxydopamine to neonatal rats produces a rapid and profound depletion of brain dopamine. Total activity of treated animals is significantly greater than that of controls between 12 and 22 days of age, but then declines, an activity pattern similar to that seen in affected children. This suggests a functional deficiency of brain dopamine in the pathogenesis of minimal brain dysfunction.
Memory: Proline Induces Retrograde Amnesia in Chicks
Authors: Cherkin Arthur , Eckardt Michael J. , Gerbrandt Lauren K.
Published: October 2006

Intracerebral injection of L-proline, 1 minute after one-trial avoidance training of chicks, impaired memory 24 hours later. Chicks injected with proline 1 or 4 hours after training and controls injected with L-isoleucine at intervals after training, showed no impairment of memory 24 hours after training. The retrograde impairment of long-term memory induced by proline occurred without the convulsions or electrographic events usually associated with retrograde amnesic treatments.
The Clonal Evolution of Tumor Cell Populations
Authors: Nowell Peter C.
Published: October 2006

It is proposed that most neoplasms arise from a single cell of origin, and tumor progression results from acquired genetic variability within the original clone allowing sequential selection of more aggressive sublines. Tumor cell populations are apparently more genetically unstable than normal cells, perhaps from activation of specific gene loci in the neoplasm, continued presence of carcinogen, or even nutritional deficiencies within the tumor.

The acquired genetic instability and associated selection process, most readily recognized cytogenetically, results in advanced human malignancies being highly individual karyotypically and biologically. Hence, each patient's cancer may require individual specific therapy, and even this may be thwarted by emergence of a genetically variant subline resistant to the treatment. More research should be directed toward understanding and controlling the evolutionary process in tumors before it reaches the late stage usually seen in clinical cancer.
Nuclear Inclusions in Paget's Disease of Bone
Authors: Mills Barbara G. , Singer Frederick R.
Published: October 2006

The ultrastructure of bone cells was examined in biopsies from 18 patients with Paget's disease of bone and from 60 patients with a variety of other bone diseases. A characteristic nuclear inclusion was found in the osteoclasts of each patient with Paget's disease. The nuclear inclusion most closely resembles viral nucleocapsids of the measles type.
Sexual Dimorphism in Vocal Control Areas of the Songbird Brain
Authors: Nottebohm Fernando , Arnold Arthur P.
Published: October 2006

In canaries and zebra finches, three vocal control areas in the brain are strikingly larger in males than in females. A fourth, area X of the lobus parolfactorius, is well developed in males of both species, less well developed in female canaries, and absent or not recognizable in female zebra finches. These size differences correlate well with differences in singing behavior. Males of both species learn song by reference to auditory information, and females do not normally sing. Exogenous testosterone induces singing in female canaries but not in female zebra finches. This is believed to be the first report of such gross sexual dimorphism in a vertebrate brain.
The Effect of Propamidine on Bacterial Metabolism
Authors: Bernheim Frederick
Published: October 2006

M/80,000 propamidine inhibits the oxidation of the nitrogeneous constituents of the medium in which the bacteria grow. A certain latent period occurs before the inhibition reaches a maximum and the drug is more effective at pH 7.8 than at pH 6.7. As is shown in the accompanying article by Dr. Kohn, this concentration is in the minimal effective range for the inhibition of growth. A latent period and a similar pH effect also are present when growth is inhibited. It is thus possible to conclude that propamidine, unlike sulfanilamide and its derivatives, directly affects the oxidative metabolism of these bacteria.
Amianthoid Change: Orientation of Normal Collagen Fibrils During Aging
Authors: Hukins David W. L. , Knight David P. , Woodhead-Galloway John
Published: October 2006

High-angle x-ray diffraction provides direct evidence that amianthoid change, occurring during aging of costal cartilage, corresponds to a transformation from an isotropic to a marked anisotropic distribution of collagen fibrils. Low-angle x-ray diffraction and electron microscopy show that the fibrils have the customary 67-nanometer axial periodicity. Electron microscopy shows that wide amianthoid collagen fibrils consist of smaller parallel fibrils fused together. Similarities between amianthoid change and tendon morphogenesis are briefly discussed. Amianthoid change is remarkable in that aging is accompanied by increased order.
Impurities in Labeled Diethylstilbestrol: Identification of Pseudodiethylstilbestrol
Authors: Tennent D. M. , Kouba R. F. , Ray W. H. , VandenHeuvel W. J. A. , Wolf F. J.
Published: October 2006

Radioactive impurities known to exist in labeled diethylstilbestrol used in tissue residue studies in cattle include at least five different compounds, one of which is identified as pseudodiethylstilbestrol.
HIERARCHICAL AND MIXING PROPERTIES OF STATIC COMPLEX NETWORKS EMERGING FROM FLUCTUATING CLASSICAL RANDOM GRAPHS
Authors: ABE SUMIYOSHI , THURNER STEFAN
Published: October 2006

The Erdös–Rényi classical random graph is characterized by a fixed linking probability for all pairs of vertices. Here, this concept is generalized by drawing the linking probability from a certain distribution. Such a procedure is found to lead to a static complex network with an arbitrary connectivity distribution. In particular, a scale-free network with the hierarchical organization is constructed without assuming any knowledge about the global linking structure, in contrast to the preferential attachment rule for a growing network. The hierarchical and mixing properties of the static scale-free network thus constructed are studied. The present approach establishes a bridge between a scalar characterization of individual vertices and topology of an emerging complex network. The result may offer a clue for understanding the origin of a few abundance of connectivity distributions in a wide variety of static real-world networks.
Differentiated Dopaminergic MN9D Cells Only Partially Recapitulate the Electrophysiological Properties of Midbrain Dopaminergic Neurons
Authors: Rick C.E. , Ebert A. , Virag T. , Bohn M.C. , Surmeier D.J.
Published: October 2006

The cell line MN9D, a fusion of embryonic ventral mesencephalic and neuroblastoma cells, is extensively used as a model of dopamine (DA) neurons because it expresses tyrosine hydroxylase and synthesizes and releases DA. These cells are also used to test mechanisms and potential therapeutics relevant to the loss of DA neurons in Parkinson’s disease. To date, little work has been done to determine whether MN9D cells electrophysiologically resemble mature DA neurons. We examined sodium, calcium and potassium currents in undifferentiated and differentiated MN9D cells, and compared these to those found in acutely dissociated mouse substantia nigra pars compacta DA neurons. It was observed that undifferentiated MN9D cells bore no resemblance to DA neurons. Upon differentiation with butyric acid with or without a prior treatment with glial cell line-derived neurotrophic factor, differentiated MN9D cells produce an electrophysiological profile that more closely resembles substantia nigra pars compacta DA neurons even though the A-type potassium current remains noticeably absent. These observations demonstrate that undifferentiated MN9D cells are not reasonable models of DA neurons. Although differentiated MN9D cells are closer to the mature DA neuronal phenotype, they do not fully mimic DA neurons and are likely to be of questionable value as a model because of their substantive differences, including the lack of the characteristic A-type potassium current. The future use of one or a combination of growth or other factors to differentiate MN9D cells may yield a more useful model system for Parkinson’s disease studies in vitro.
New Evidence of H1-Receptor Independent COX-2 Inhibition by Fexofenadine HCl in vitro
Authors: Juergens Uwe R. , Gillissen Adrian , Uen Sakir , Racké Kurt , Stöber Meinolf , Darlath Wilfried , Vetter Hans
Published: October 2006

Background/Aims: Fexofenadine HCl (FEX) has previously been shown to have anti-inflammatory properties in relieving nasal congestion in allergic rhinitis. The objective of this study was to further elucidate the mechanism of action behind the anti-inflammatory properties of FEX in addition to its H1-receptor antagonism. Methods: The effects of two antihistamines, FEX and loratadine (LOR), were investigated on cyclooxygenase (COX)-1 and -2 enzymesin vitro. FEX (10–9–10–3 mol/l) and LOR (10–9–10–4 mol/l) were incubated with arachidonic acid in a COX screening assay with either ovine COX-1 or COX-2 or human COX-2. COX-2 enzyme inhibitory activity for the antihistamines was compared with the known selective COX-2 inhibitor DuP-679. Results: High concentrations of FEX (10–3 mol/l) significantly inhibited arachidonic acid-mediated ovine COX-1 activity, but low concentrations had no effect. Low concentrations of FEX (10–8 mol/l) inhibited ovine COX-2 activity, and this inhibition decreased with increasing concentrations. The inhibition of COX-2 activity by FEX was similar to that seen with the selective COX-2 inhibitor, DuP-679. Conversely, LOR inhibited COX-1 activity at low concentrations (10–8 mol/l), but had little inhibitory effect on COX-1 at high concentrations. LOR (10–5 mol/l) markedly stimulated COX-2 activity. Conclusion: FEX showed selective arachidonic acid-mediated COX-2 inhibitory enzyme activity, which differed markedly from the COX inhibitory enzyme activity of LOR. This selective COX-2 inhibitor activity by FEX may contribute to its anti-inflammatory properties in relieving nasal congestion in allergic rhinitis.
Endocrinological Markers for Assessment of Hyperandrogenemia in Hirsute Women
Authors: Mueller Andreas , Cupisti Susanne , Binder Helge , Hoffmann Inge , Kiesewetter Franklin , Beckmann Matthias W. , Dittrich Ralf
Published: October 2006

Background: Measured endocrinological parameters (total testosterone [TT], free testosterone [FT], dihydrotestosterone [DHT], dehydroepiandrosterone sulfate [DHEAS], and sex hormone binding globulin [SHBG]) and calculated parameters (calculated FT (cFT), calculated bioavailable testosterone (cBT), and the free androgen index [FAI]) in women with hirsutism were compared to the values of a control group. The question remains if cFT or cBT are more appropriate markers for assessment of hyperandrogenemia in clinical situations such as hirsutism in women. Methods: Sixty-six women showed an modified Ferriman-Gallwey (mF-G) score of ≧6 and were classified as hirsutism group and 58 women showed mF-G scores of ≤5 and were classified as control group. TT, FT, DHT, DHEAS, and SHBG were measured with enzyme immunoassays in one serum sample. Albumin was measured in the same sample. Afterwards, cFT, cBT, and the FAI were calculated. Results: The hirsutism group revealed significantly increased cFT, cBT, and FAI, while SHBG was significantly decreased compared to the controls. All values of the hirsutism group showed significant, but poor correlation with the mF-G score. SHBG correlated negatively with the mF-G score and BMI. Conclusion: Despite the limited correlation of all endocrinological parameters to severity of hirsutism described by the mF-G score, cFT, cBT, and FAI may be more appropriate markers for assessment of hyperandrogenemia in women with hirsutism in comparison with measured values of simple enzyme immunoassays.
Teacher Self-Efficacy, Burnout, Experience and Decision to Refer a Disruptive Student
Authors: Egyed Carla J. , Short Rick Jay
Published: October 2006

The purpose of this study was to investigate teacher characteristics that may lead to special education referrals, including efficacy, burnout, experience, and preparation. We hypothesized that likelihood to refer for special education is related to these teacher characteristics. This study involved 106 elementary teachers who rated themselves on the Maslach Burnout Inventory (MBI) and the Teacher Efficacy Scale (TES). They were given a case vignette of a child exhibiting behavioural problems in a classroom and were asked how likely they would be to refer the child for special education assessment. Analyses revealed that teachers who were uncertain whether they would refer a child for special education testing had higher levels of burnout than teachers who were more decided about whether to refer. No relationship was found between teacher sense of efficacy, experience, or preparation and decision to refer. Significant correlations between the subscales on the MBI and the TES suggest an inverse relationship between teacher sense of efficacy and teacher burnout.
Explanations of socioeconomic differences in changes in physical function in older adults: results from the Longitudinal Aging Study Amsterdam
Authors: Koster Annemarie , Bosma Hans , Broese van Groenou Marjolein I , Kempen Gertrudis IJM , Penninx Brenda WJH , van Eijk Jacques ThM , Deeg Dorly JH
Published: October 2006

Background

This study examines the association between socioeconomic status and changes in physical function in younger- (aged 55–70 years) and older-old (aged 70–85 years) adults and seeks to determine the relative contribution of diseases, behavioral, and psychosocial factors in explaining this association.

Methods

Data were from 2,366 men and women, aged 55–85 years, participating in the Longitudinal Aging Study Amsterdam (LASA). Two indicators of socioeconomic status were used: education and income. Physical function was measured by self-reported physical ability over nine years of follow-up.

Results

In older adults, low socioeconomic status was related to a poorer level of physical function during nine years of follow-up. In subjects who were between 55 and 70 years old, there was an additional significant socioeconomic-differential decline in physical function, while socioeconomic differentials did not further widen in subjects 70 years and older. Behavioral factors, mainly BMI and physical activity, largely explained the socioeconomic differences in physical function in the youngest age group, while psychosocial factors reduced socioeconomic status differences most in the oldest age group.

Conclusion

The findings indicate age-specificity of both the pattern of socioeconomic status differences in function in older persons and the mechanisms underlying these associations.
Testosterone and Progesterone Rapidly Attenuate Plasma Membrane Gβγ-Mediated Signaling in Xenopus laevis Oocytes by Signaling through Classical Steroid Receptors
Authors: Evaul Kristen , Jamnongjit Michelle , Bhagavath Bala , Hammes Stephen R.
Published: October 2006

Many transcription-independent (nongenomic) steroid effects are regulated by G proteins. A well-established, biologically relevant example of steroid/G protein interplay is steroid-triggered oocyte maturation, or meiotic resumption, in Xenopus laevis. Oocyte maturation is proposed to occur through a release of inhibition mechanism whereby constitutive signaling by Gβγ and other G proteins maintains oocytes in meiotic arrest. Steroids (androgens in vivo, and androgens and progesterone in vitro) overcome this inhibition to promote meiotic resumption. To test this model, we used G protein-regulated inward rectifying potassium channels (GIRKs) as markers of Gβγ activity. Overexpression of GIRKs 1 and 2 in Xenopus oocytes resulted in constitutive potassium influx, corroborating the presence of basal Gβγ signaling in resting oocytes. Testosterone and progesterone rapidly reduced potassium influx, validating that steroids attenuate Gβγ activity. Interestingly, reduction of classical androgen receptor (AR) expression by RNA interference abrogated testosterone’s effects on GIRK activity at low, but not high, steroid concentrations. Accordingly, androgens bound to the Xenopus progesterone receptor (PR) at high concentrations, suggesting that, in addition to the AR, the PR might mediate G protein signaling when androgens levels are elevated. In contrast, progesterone bound with high affinity to both the Xenopus PR and AR, indicating that progesterone might signal and promote maturation through both receptors, regardless of its concentration. In sum, these studies introduce a novel method for detecting nongenomic steroid effects on G proteins in live cells in real time, and demonstrate that cross talk may occur between steroids and their receptors during Xenopus oocyte maturation.
Histopathology of congenital subglottic stenosis
Authors: Tucker Gabriel F. , Ossoff Robert H. , Newman Anita N. , Holinger Lauren D.
Published: October 2006

Three patients with congenital subglottic stenosis are presented and whole organ serial‐section studies of their larynges are discussed. A superiorly displaced first tracheal ring is observed to form a cartilaginous subglottic stenosis in one. This “trapped first ring” is demonstrated in horizontal, sagittal and coronal planes. Subglottic stenosis is a clinical diagnosis which describes multifarious histopathological forms of narrowing within the subglottic larynx.
The prognostic significance of metastatic cervical lymph nodes
Authors: Schuller David E. , McGuirt W. Fred , McCabe Brian F. , Young Donn
Published: October 2006

The ability to predict accurately the clinical course of a patient with a malignancy is critically important to the patient's subsequent management. It has been well documented that the presence of metastatic nodal disease is associated with decreased patient survival. Survival data from a group of 242 head and neck cancer patients from the University of Iowa were analyzed to determine the significance of specific characteristics of metastatic lymph nodes. Evaluation of absolute numbers and percentages of positive nodes or node size generally was not useful. However, involvement of the posterior triangle nodes, non‐contiguous nodal sites, or multiple sites was associated with a worse prognosis. When nodal features were considered individually or collectively, there was no consistent finding that was accurate enough to be of help to the clinician in prognostication. The single most important feature seems to be documentation of the presence of metastatic nodal disease, rather than particular features (i.e., number, size) of the metastatic nodes.
Sucking Performance of Babies with Cleft Conditions
Authors: Reid Julie , Reilly Sheena , Kilpatrick Nicky
Published: October 2006

Objective:

To describe the sucking performance of bottle-fed babies with cleft conditions.

Participants:

Forty 2-week-old-babies with cleft lip (CL; n = 8), cleft palate (CP; n = 22), and cleft lip and palate (CLP; n = 10) were examined.

Methods:

Suction, compression, and other sucking parameters were measured during bottle-feeding and compared to determine if they varied with cleft condition or feeding ability.

Results:

All babies with CL and one with CLP demonstrated suction. Thirteen of 22 babies with CP demonstrated suction but only three maintained regular pressure changes over time. Between-group differences in the amplitude of suction and compression were associated with cleft condition. Cleft lip participants demonstrated the greatest amplitude of suction followed by those with CP and CLP. Cleft lip and CP participants generated similar amplitudes of compression. This was greater than their counterparts with CLP. Good feeders (n = 15) generated high levels of suction, while satisfactory (n = 15) and poor feeders (n = 10) did not generate any during bottle-feeding.

Conclusion:

Between-group differences in intra-oral pressures were confirmed when babies were examined by cleft condition. Babies with smaller clefts (i.e., CL or minor soft palate clefts) were more likely to generate normal levels of suction and compression compared to their counterparts with larger clefts. Since good feeders were more likely to have smaller clefts it was not surprising that they demonstrated higher suction pressures than babies with satisfactory or poor feeding ability. Compression values were not significantly different across the feeding ability groups. These data may inform feeding management strategies.
Sonographic diagnosis of a saccular aneurysm of the internal jugular vein
Authors: Lee Hwa Yeon , Yoo Seung Min , Song In‐Sup , Yu Hyeon , Lee Jong Beum
Published: October 2006

Aneurysm of the internal jugular vein is an extremely rare condition. It is usually detected during childhood and is characterized by being more prominent during Valsalva maneuvers such as vomiting, coughing, and straining. Most of the cases reported in the English literature are fusiform aneurysms of the internal jugular vein. We report the case of a saccular aneurysm of the left internal jugular vein in a 59‐year‐old woman with no change in size of the aneurysm during a Valsalva manuever. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound, 2006
The utility of zebrafish for studies of the comparative biology of motor systems
Authors: Fetcho Joseph R.
Published: October 2006

Although zebrafish are best known as a model for studies of development, there is now a growing role for the model in studies of the functional organization of the nervous system, including studies of a variety of sensory systems, central processing, and motor output. The zebrafish has much to offer for such work because of the unique combination of genetics, optical methods, and physiology it allows. Here I illustrate, using three examples, the broad range of avenues along which zebrafish can inform us about motor systems. The examples include efforts to understand the functional organization and evolution of spinal interneurons, the role of mutants in informing us about motor dysfunction and human disease, and the ability to use the special features of zebrafish to explore strategies to restore function after injury. The most important aspects of these studies are evident only when they are placed in a comparative context, so they serve to highlight the power of zebrafish in studies of the comparative biology of motor control. J. Exp. Zool. (Mol. Dev. Evol.) 308B:550–562, 2007. © 2006 Wiley‐Liss, Inc.
Evolution of chemical, biological, and physical water properties in the northern California Current in 2005: Remote or local wind forcing?
Authors: Hickey B. , MacFadyen A. , Cochlan W. , Kudela R. , Bruland K. , Trick C.
Published: October 2006

The spring onset of persistent upwelling‐favorable winds was later than usual in the northern California Current system in 2005, resulting in delayed provision of inorganic nutrients to the upper waters of the coastal ocean. This study uses water column measurements to illustrate the evolution of temperature, salinity, nitrate and chlorophyll a prior to and after the onset of persistent local upwelling‐favorable winds, including recovery to “typical” conditions. Warm, nutrient‐ and chlorophyll‐depleted surface conditions similar to those in an El Niño were observed from Vancouver Island to central Oregon, and extended to depths greater than 500 m. Return to typical conditions was more rapid than suggested by time‐integrated local wind stress but consistent in timing with “remote” forcing of water properties in this region by upwelling‐favorable winds off northern California. Alongshore advection also likely contributed to the observed recovery, but was much less effective than upwelling.
Application of a pigment measuring device – Mexameter®– for the differential diagnosis of vitiligo and nevus depigmentosus
Authors: Park Eun Sang , Na Jung Im , Kim Seon Ok , Huh Chang Hun , Youn Sang Woong , Park Kyoung Chan
Published: October 2006

Background/purpose: Vitiligo and nevus depigmentosus (ND) present similar hypopigmented macules with significantly different prognoses. Although the distinction between the two diseases is important, differential diagnosis relies on medical history and physical examination, which is far from decisive in some cases. The Mexameter® is an objective skin color‐measuring device, and has been reported to provide a reproducible and sensitive means of quantifying small skin color differences. In this study, we investigated the usefulness of a Mexameter® for discriminating these diseases.

Methods: A selection of 202 hypopigmented skin lesions (182 from vitiligo and 20 from ND) were the objects of this study. Using a Mexameter, MIs were obtained from lesions and symmetrically located control skin. RMIs, ratios of the MIs of lesional skins to control skins, were calculated.

Results: The mean MIs and RMIs were significantly different for vitiligo and ND. The mean RMI of ND lesions was 74±13, which was significantly higher than that of vitiligo lesions (50±24). No ND lesion had an RMI of <50%.

Conclusion: This study shows that the Mexameter®, an objective pigment‐measuring device, can be used to achieve a more accurate diagnosis of hypopigmentary disorders, and that the relative melanin index (RMI), which represents the relative pigment levels, might be a more effective parameter than the melanin index (MI) itself for comparing pigmentation differences.
Odour‐mediated preference and prey preference of Macrolophus caliginosus between spider mites and green peach aphids
Authors: Moayeri H. R. S. , Ashouri A. , Brødsgaard H. F. , Enkegaard A.
Published: October 2006

Abstract  A comparative study between direct prey preference and odour‐mediated preference of the predatory mirid bug, Macrolophus caliginosus, was conducted. We used a Y‐tube olfactometer to determine the attraction of the predator to herbivore‐induced volatiles from Myzus persicae or Tetranychus urticae‐infested sweet pepper plants over clean plants and to direct prey odours over clean air. The mirid bugs showed a stronger response to odours from infested plants than to odours from clean plants. The mirids did, however, not seem to exploit odours emitted directly from the prey themselves. Our results further demonstrated that M. caliginosus prefers M. persicae to T. urticae in a direct two‐choice consumption test. This preference was, however, not reflected in a similar odour‐mediated preference between plant volatiles induced by either of the two preys. Two hypotheses are suggested for this neutral response of the mirids to herbivore‐induced volatiles from a preference prey or a non‐preference prey.
Transport of proteins and ribonacleic acid along nerve axons
Authors: Austin L. , Bray J. J. , Young R. J.
Published: October 2006

The distribution of isotope in the sciatic nerve was determined at times up to 22 days after injection of (a) [14C]leucine, or (b) [3H]orotic acid, in the spinal cord of the chicken. The results indicate a distal flow of proteins, RNA precursors and perhaps RNA along the nerve axon.
ALANINE METABOLISM IN RAT CORTEX IN VITRO
Authors: Cory H. Therese , Rose S. P. R
Published: October 2006

Abstract— (1) The metabolism of [U‐14C]alanine was followed in slices of rat cerebral cortex and its interaction with glucose, pyruvate and the metabolic inhibitors fluoracetate and malonate was studied.

(2) Alanine did not stimulate respiration above endogenous levels or affect the rate of oxygen uptake with glucose or pyruvate as cosubstrate. Radioactivity found in CO2 from labelled alanine was only 6 per cent of that from labelled pyruvate. Lactate was not formed from alanine.

(3) After 2 h incubation with [U‐14C]alanine the specific activities of glutamate, glutamine and GABA were 20–30 per cent that of alanine. All these specific activities except glutamate were lowered by addition of glucose, but with pyruvate as cosubstrate the specific activity of glutamate was increased by 87 per cent above the level with alanine alone.

(4) The effect of alanine as cosubstrate with [U‐14C]pyruvate was to reduce the specific activity of GABA and of glutamine, but not glutamate or lactate; thus there was not an equal dilution of all the metabolites of pyruvate.

(5) Fluoracetate diminished respiration and the production of CO2 from [U‐14C]‐alanine only slightly; the addition of malonate as well practically abolished both. Fluoracetate lowered incorporation from alanine into all the amino acids, and radioactivity could not be detected in glutamine at all; addition of malonate lowered the specific activity of glutamate to 25 per cent but increased that into aspartate, GABA and glutamine.

(6) The interpretation of these data in terms of known pathways of alanine metabolism is discussed.
BIOSYNTHESE DES GLYCOPROTEINES CEREBRALES: ETUDE DE L'ACTIVITE MANNOSYL‐TRANSFERASE PARTICULEE DU CERVEAU
Authors: Broquet P. , Richard M. , Louisot P.
Published: October 2006

Résumé—

Dans le cerveau, I'activité mannosyl‐transférase, du GDP‐mannose à un accepteur glycoprotéinique endogène, est localisée au niveau de la fraction des microsomes et fragments de synaptosomes des cellules cérébrales. Ce système polyenzymatique complexe se caractérise par deux maxima d'activitéà deux pH différents, respectivement 5,9 et 7,4. Le système est activé après une pré‐incubation à température supra‐optimale, qui modifie les conditions d'environnement enzyme‐substrat. I1 est également activé par le Triton X‐100 à certaines concentrations, et par les cations Mn2+ et Mg2+. A I'opposé, il est inhibé par les nucleosides‐diphosphates, le GTP et le β‐γ‐methylène‐GTP. Le cycloheximide n'a pas d'effet sur la transglycosylation, mais la puromycine réduit I'activité mannosyl‐transférase. Ceci met en évidence I'importance, dans le modèle cérébral, de la persistance de l'attachement des chaines polypeptidiques aux polysomes pendant I'exécution du processus de transglycosylation.
MEASUREMENT OF THE RATE OF ACETYLCHOLINE DIFFUSION THROUGH A BRAIN SLICE AND ITS SIGNIFICANCE IN STUDIES OF THE CELLULAR DISTRIBUTION OF ACETYLCHOLINESTERASE
Authors: Lancaster R.
Published: October 2006

Abstract—

The rate of ACh diffusion through a 0·8 mm thick slice from the surface of the rat cerebral cortex, under aerobic conditions at 37°C, was determined by bathing the intact surface of the slice (compartment A) with ACh containing buffer and determining the concentration of ACh in buffer bathing the cut surface of the slice (compartment B). With 1 or 5 mM‐ACh in compartment A no ACh was detectable in compartment B within 3 h unless at least 95 per cent of the AChE, as assessed on homogenates, was inhibited. With a given level of AChE inhibition, the rate of ACh diffusion was dependent on its concentration in compartment A. With 1 mM‐ACh in compartment A the difference between the rates of hydrolysis of ACh during diffusion through slices with an AChE inhibition of 98·3 and 99·4 per cent, as assessed by AChE assays of homogenates made from the slices, was only 6 per cent of the difference between the rates of hydrolysis of 1 m‐ACh by the homogenates of that part of the slices through which diffusion took place. For 5 mM‐ACh and levels of 95 and 99·2 per cent inhibition the corresponding value was 10‐3 per cent. Since the concentration of ACh must fall across the slice it is not possible to calculate from these figures the number of enzyme sites involved in the hydrolysis during diffusion, i.e. the concentration of extracellular AChE. The implications of these observations are discussed, particularly in relation to studies of the release of ACh from the cerebral cortex in vivo
OCCURRENCE OF N‐ACETYLALANINE IN THE HUMAN BRAIN1
Authors: Auditore J. V. , Wade L.
Published: October 2006

Abstract—

A substance identical with N‐acetyl‐l‐alanine was isolated from an aqueous extract of human brain by a combination of paper and ion‐exchange Chromatography. The isolated substance did not react with ninhydrin reagent but yielded alanine upon acid hydrolysis. An acetyl hydrazide was identified by paper chromatography of hydrazinolysates of the isolated substance and N‐acetyl‐l‐alanine. The unknown alanine had the l‐configuration. The results of elementary analysis of the isolated compound were in full accord with the analysis calculated for synthetic N‐acetyl‐l‐alanine.