bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced trabecular-bone calcium deposition in female rats with a high physiological dose of prolactin diminishes after ovariectomy
Authors: Puntheeranurak Supaporn , Charoenphandhu Narattaphol , Krishnamra Nateetip
Published: December 2006

Although an increase in trabecular-bone calcium deposition has been shown to be regulated by prolactin during lactation, the physiological significance of prolactin in bone calcium metabolism in nonlactating rats remains unclear. This investigation sought to demonstrate the effects of endogenous prolactin and a high physiological dose of exogenous prolactin on bone turnover and bone calcium deposition in normal female rats, using the45Ca-labeling technique. Our results showed that suppression of endogenous prolactin with 6 mg/kg bromocriptine for 15 days significantly enhanced bone formation, but not bone resorption, in primarily trabecular sites, resulting in a significant increase in calcium deposition in the sternum and vertebrae, from –0.20 ± 0.07 to 0.40 ± 0.09 (p < 0.05) and –0.07 ± 0.11 to 0.34 ± 0.06 (p < 0.05) mmol Ca·(g dry mass)–1, respectively. Similarly, 2.5 mg/kg prolactin, a high physiological dose, increased sternal and vertebral calcium deposition, from –0.20 ± 0.07 to 0.24 ± 0.09 (p < 0.05) and –0.07 ± 0.11 to 0.25 ± 0.18 (p < 0.05) mmol Ca·(g dry mass)–1, respectively, by increasing bone formation more than bone resorption. However, as expected, prolactin had no effect on the tibia or femur, which are primarily cortical sites. Because several actions of prolactin have been known to be estradiol-dependent, we further investigated the dependence of prolactin action on 17β-estradiol. We found that 2.5 mg/kg prolactin did not increase sternal calcium deposition in ovariectomized rats. However, 10 µg/kg 17β-estradiol supplementation restored the action of prolactin. Ovariectomized rats given 17β-estradiol plus prolactin also manifested slightly but significantly higher sternal total calcium content than sham-operated rats, (4.58 ± 0.12 vs. 4.36 ± 0.11 mmol Ca·(g dry mass)–1(p < 0.05)). We concluded that a high physiological dose of prolactin promoted calcium deposition in primarily trabecular sites of nonlactating rats. This effect was diminished after ovariectomy. In addition, we showed that basal endogenous prolactin played a role in the maintenance of normal trabecular-bone turnover.
Anti-fibrotic effects of tetrandrine on bile-duct ligated rats
Authors: Hsu Yi-Chao , Chiu Yung-Tsung , Lee Chang-Yin , Wu Ching-Fen , Huang Yi-Tsau
Published: December 2006

Tetrandrine (Tet) (C38H42O8N2; molecular weight, 622), an alkaloid isolated from the Chinese medicinal herb Stephania tetrandra, has been shown to elicit anti-inflammatory and anti-fibrotic effects in pulmonary diseases, but the mechanism of action has yet to be investigated. In this study, we tested whether Tet exerts anti-fibrotic effects on rat hepatic fibrosis through anti-NFκB pathways. After bile-duct ligation, rats were given Tet (1 or 5 mg/kg) or silymarin (50 mg/kg, as a positive control) by gavage twice daily for 3 weeks. Liver sections were taken for Sirius red quantitative scoring, immunofluorescence double staining of α-smooth muscle actin (α-SMA) and NFκB, and for quantitative determinations of the mRNA expression levels of TGF-β1, α-SMA, collagen 1α2, inducible nitric oxide synthase (iNOS), intercellular adhesion molecule 1 (ICAM-1), metallothionein, vascular endothelial growth factor (VEGF), and VEGF type II receptor (VEGFR2) genes. The results showed that both Tet and silymarin treatment significantly reduced the fibrosis scores and hepatic collagen content of BDL rats, compared with no treatment. Both Tet and silymarin treatments decreased the number of α-SMA- and NFκB-positive cells in fibrotic livers. Moreover, Tet and silymarin treatments attenuated the mRNA expression levels of TGF-β1,α-SMA, collagen 1α2, iNOS, ICAM-1, VEGF, and VEGFR2 genes, and induced the mRNA expression of the metallothionein gene. This study suggests that the anti-fibrotic effects of Tet were related to the reduction of fibrosis-related gene transcription, the attenuation of NFκB-activated pathways, and the induction of metallothionein gene transcription in the livers of BDL rats.
Intraspecific and interspecific variation in use of forest-edge habitat by snakes
Authors: Carfagno Gerardo L.F. , Weatherhead Patrick J.
Published: December 2006

Variation in use of edge habitat among populations and species of snakes should reflect underlying causes (e.g., thermal ecology, prey availability) and consequences (e.g., predation on birds' nests) of habitat selection. We compared the habitat use of ratsnakes, Elaphe obsoleta (Say in James, 1823), in Illinois and Ontario and compared habitat use by ratsnakes and racers, Coluber constrictor (L., 1758), in Illinois. Ratsnakes in Illinois used upland forest more and forest edges less than ratsnakes in Ontario. Female ratsnakes in Illinois used edges less than males, regardless of their reproductive status. Relative to ratsnakes, racers preferred forest edges and avoided forest interior. Female racers used edges more than males, especially while gravid. These results, and most of the seasonal patterns in habitat use, were broadly consistent with variation expected from differences in thermoregulatory needs, although other factors potentially influencing habitat use cannot be ruled out. Although it has been proposed that some forest fragmentation is likely to be beneficial for ratsnakes in Canada, such fragmentation may be detrimental to ratsnakes in Illinois but beneficial to racers. Thus, relative to forest-interior species, edge-nesting birds should be more vulnerable to predation by ratsnakes in Ontario, and fragmentation should increase the vulnerability of forest birds to nest predation by racers.
Ecological correlates of roe deer fawn survival in a sub-Mediterranean population
Authors: Raganella-Pelliccioni E. , Boitani L. , Toso S.
Published: December 2006

We investigated the effect of body mass, spring and summer total rainfall, birth period, and local population density on the survival of 130 roe deer ( Capreolus capreolus (L., 1758)) fawns captured over seven fawning seasons (1997–2003) and radio-monitored daily. We modelled survival using the program MARK, incorporating biological questions into different models, following a priori hypotheses. The best model was selected using Akaike’s information criterion. The population was surveyed by counts and estimates were obtained using mark–resight methods. Weekly survival of roe deer fawns exhibits a pseudo-threshold time trend. Probability of survival is low (0.33 ± 0.0046) in summer, increases (0.79 ± 0.0021) in fall, and approaches the highest value typical of adult survival (0.90 ± 0.00091 and 0.96 ± 0.00021 by the end of March and May, respectively) during early spring following birth. The final model predicts that survival of roe deer fawns is positively affected by total precipitation in spring and body mass under a pseudo-threshold time variation pattern. In contrast with other studies, we did not detect any effect of population density on survival of fawns. This study contributes to the scarce knowledge about the performance of roe deer populations in Mediterranean ecosystems, providing evidence that climate variables and individual characteristics shape the vital rates of roe deer populations.
Density-dependent growth of double-crested cormorant colonies on Lake Huron
Authors: Ridgway Mark S. , Pollard J. Bruce , Weseloh D.V. Chip
Published: December 2006

By analyzing 20+ years of data, we found that the nesting colonies of double-crested cormorants ( Phalacrocorax auritus (Lesson, 1831)) in the North Channel and Georgian Bay of Lake Huron exhibit density-dependent population regulation. This conclusion is based on four lines of evidence. First, a time series of nest counts at specific colonies (1979–2001) showed density-dependent growth based on randomization tests of the time series. Second, the per capita rate of change in colony size declined with increasing colony size over a 10-year period. Third, a Ricker model of aggregate nest counts showed that population growth of nesting double-crested cormorants stabilized in recent years (through 2003), with K, the carrying capacity parameter, being 11 445 nests in the North Channel and 10 815 nests in Georgian Bay. Fourth, a colony area index showed near complete coverage of coastal areas by adult nesters coinciding with overall declines in population growth. High rates of population increase of double-crested cormorants on Lake Huron have largely come to an end, but changes in fish abundance may result in changes in carrying capacity.
QUANTUM REFLECTION, EVAPORATION, AND TRANSPORT CURRENTS AT 4He SURFACES
Authors: APAJA V. , KROTSCHECK E. , RIMNAC A. , ZILLICH R. E.
Published: December 2006

In this work, we study transport currents in excited states. This requires the calculation of particle currents [Formula: see text] to second order in the excitation amplitudes. For that purpose, we take a well-tested microscopic theory of inhomogeneous quantum liquids and extend it to find the mass currents created when atoms scatter off a surface or when excitations evaporate atoms. This is the first theoretical study of transport phenomena in a quantum liquid based on a quantitative microscopic theory.
RADIAL DISTRIBUTION AND LIQUID STRUCTURE FUNCTION FOR LIQUID PARA-HYDROGEN AT LOW TEMPERATURES
Authors: GERNOTH KLAUS A. , HARRISON MATTHEW J. , RISTIG MANFRED L.
Published: December 2006

We present theoretical results for the radial distribution function g(r) and the static liquid structure function S(k) of liquid para-hydrogen at low temperatures. The results have been obtained via quantum Monte Carlo Path Integral simulations, classical Monte Carlo calculations, and correlated density matrix theory.
VARIATIONAL DESCRIPTION OF WEAKLY INTERACTING BOSE GASES IN 3 DIMENSIONS
Authors: MAZZANTI F. , SAARELA M. , APAJA V.
Published: December 2006

Static and dynamic properties of a weakly interacting Bose gas of Hard Spheres in three dimensions are studied in the framework of the Correlated Basis Functions (CBF) approximation. Results are compared with explicit expressions for the same quantities derived within the Bogoliubov model. Despite the good agreement in the energy of the groundstate and the excited states, other quantities such as the dynamic structure function present important differences that become more significant when the density is raised.
STABILITY AND SPECTRA OF SMALL 3He-4He CLUSTERS
Authors: NAVARRO J. , FANTONI S. , GUARDIOLA R. , ZUKER A.
Published: December 2006

Diffusion Monte Carlo calculations have been systematically performed to analyze the stability of small mixed 3 He -4 He clusters, as well as their excitation spectra. The picture that emerges is that of systems with strong shell effects whose binding and excitation energies are essentially determined by the monopole properties of an effective Hamiltonian.
BOSE–EINSTEIN CONDENSATION IN BULK AND CONFINED SOLID HELIUM
Authors: REATTO L. , ROSSI M. , GALLI D. E.
Published: December 2006

We address the question if the ground state of solid 4 He has the number of lattice sites equal to the number of atoms (commensurate state) or if it is different (incommensurate state). We point out that energy computation from simulation as performed by now cannot be used to decide this question and that the presently best variational wave function, a shadow wave function, gives an incommensurate state. We have extended the calculation of the one–body density matrix ρ1 to the exact Shadow Path Integral Ground State method. Calculation of ρ1 at ρ = 0.031 Å-3 shows that Vacancy–Interstitial pair processes are present also in the exact computation but the simulated system size is too small to infer the presence of off–diagonal long range order. Variational simulations of 4 He confined in a narrow cylindrical pore are also discussed.
CONTINUUM THEORY OF SUPERFLOW IN SUPERSOLID 4He: A REVIEW
Authors: SASLOW WAYNE M.
Published: December 2006

The recent observation of non-classical rotational inertia in solid 4 He for temperatures T < 200 mk , and the continued non-observation of unusual flow associated with "zero-point defectons", favors the Leggett picture of Non-Classical Rotational Inertia over the Andreev-Lifshitz zero-point defecton picture of possible superflow in this system. We discuss the nature of the wavefunction, the Leggett one-body phase function upper bound for the superfluid fraction, and more complex forms for the phase-function and how this affects the net momentum density of this many-body system. The general properties of quantum vortices in such a system are briefly discussed.
ANALYSIS OF AN INTERATOMIC POTENTIAL FOR THE CONDENSED PHASES OF HELIUM
Authors: UJEVIC SEBASTIAN , VITIELLO S. A.
Published: December 2006

A recent interatomic potential, that includes two- and three-body interactions, is used to study the liquid and solid equations of state of 4 He and other properties of this system. The high-order contributions are explicitly computed by multi-weight diffusion Monte Carlo. It turns out that this is an excellent interatomic potential for the description of condensed phases of helium atoms systems.
LIQUID 4He ADSORBED FILMS ON VERY ATTRACTIVE SUBSTRATES
Authors: URRUTIA IGNACIO , SZYBISZ LESZEK
Published: December 2006

Adsorbed films of liquid 4 He are analized, in the framework of Density functionals Theories (DF). In these systems, when the substrate becomes increasingly attractive, the thin films of 4 He approaches the quasi-bidimensional limit. We study this strongly attractive substrate regime with two DF, the Orsay-Trento (OT) and a recent Hybrid proposal (Hyb), focusing in the energy behavior. It is showed that OT does not reproduce the correct limiting energy curve, and it implies that this functional could not provide reliable results for very strongly attractive substrates like Graphite (Gr). In other hand, with the Hyb DF, the correct energy behavior is found for the adsorption energy of 4 He on Gr. These results show that OT should not be applied to quasi 2D (confinement) situations, and that Hyb DF provides a much more realistic description.
LIMITS ON THE POWER OF SOME MODELS OF QUANTUM COMPUTATION
Authors: ORTIZ GERARDO , SOMMA ROLANDO , BARNUM HOWARD , KNILL EMANUEL
Published: December 2006

We consider quantum computational models defined via a Lie-algebraic theory. In these models, specified initial states are acted on by Lie-algebraic quantum gates and the expectation values of Lie algebra elements are measured at the end. We show that these models can be efficiently simulated on a classical computer in time polynomial in the dimension of the algebra, regardless of the dimension of the Hilbert space where the algebra acts. Similar results hold for the computation of the expectation value of operators implemented by a gate-sequence. We introduce a Lie-algebraic notion of generalized mean-field Hamiltonians and show that they are efficiently (exactly) solvable by means of a Jacobi-like diagonalization method. Our results generalize earlier ones on fermionic linear optics computation and provide insight into the source of the power of the conventional model of quantum computation.
DECONFINEMENT AND COLD ATOMS IN OPTICAL LATTICES
Authors: CAZALILLA M. A , HO A. F. , GIAMARCHI T.
Published: December 2006

Despite the fact that by now one dimensional and three dimensional systems of interacting particles are reasonably well understood, very little is known on how to go from the one dimensional physics to the three dimensional one. This is in particular true in a quasi-one dimensional geometry where the hopping of particles between one dimensional chains or tubes can lead to a dimensional crossover between a Luttinger liquid and more conventional high dimensional states. Such a situation is relevant to many physical systems. Recently cold atoms in optical traps have provided a unique and controllable system in which to investigate this physics. We thus analyze a system made of coupled one dimensional tubes of interacting fermions. We explore the observable consequences, such as the phase diagram for isolated tubes, and the possibility to realize unusual superfluid phases in coupled tubes systems.
BCS-BEC CROSSOVER IN A SUPERFLUID FERMI GAS
Authors: OHASHI YOJI
Published: December 2006

We discuss the superfluid phase transition in a gas of Fermi atoms with a Feshbach resonance. A tunable pairing interaction associated with the Feshbach resonance is shown to naturally lead to the BCS-BEC crossover, where the character of superfluidity continuously changes from the weak-coupling Bardeen-Cooper-Schrieffer (BCS) type to the Bose-Einstein condensation (BEC) of tightly bound molecules, as one decreases the threshold energy 2ν of the Feshbach resonance. We also discuss effects of a trap, as well as the p-wave BCS-BEC crossover adjusted by a p-wave Feshbach resonance.
MAPPING REACTION PATHS IN PHASE-SPACE
Authors: TRAILLEUR JULIEN , TǍNASE-NICOLA SORIN , KURCHAN JORGE
Published: December 2006

Given a dynamics in configuration or phase-space, it is often important to map the barriers, the separatrices emanating from them, and the current distributions of the reaction paths. We describe a strategy to do this efficiently.
INFRARED-ABSORPTION SPECTRUM OF ELECTRON BUBBLES IN LIQUID HELIUM
Authors: PI M. , BARRANCO M. , GRAU V. , MAYOL R.
Published: December 2006

Within finite temperature Density Functional Theory, we have calculated the energy of the transitions from the ground state to the first two excited states in the electron bubbles in liquid helium at pressures from zero to about the solidification pressure. For 4 He at low temperatures, our results are in very good agreement with infrared absorption experiments. We have found that the 1s – 2p transition energies are sensitive not only to the size of the electron bubble, but also to its surface thickness. We also present results for the infrared transitions in the case of liquid 3 He .
VARIATIONAL DESCRIPTION OF FEW–NUCLEON SYSTEMS: BOUND AND SCATTERING STATES
Authors: KIEVSKY ALEJANDRO , VIVIANI MICHELE , MARCUCCI LAURA E. , ROSATI SERGIO
Published: December 2006

Three– and four–nucleon systems are described using the hyperspherical harmonic (HH) method. Bound and scattering states are expanded in the HH basis and the corresponding binding energies and S-matrices are obtained using a variational principle. Modern nucleon-nucleon potentials plus three-nucleon interactions are considered. The calculated quantities as binding energies, cross section and polarization observables are accurate at the level of 1% or better.
MURMURS AND NOISE CAUSED BY ARTERIAL NARROWING – THEORY AND CLINICAL PRACTICE
Authors: BIER MARTIN , DAY ORVILLE W. , PRAVICA DAVID W.
Published: December 2006

Arterial narrowing can cause an audible whirling in the blood flow. We propose diagnosing such narrowing by simply recording that sound and analyzing its spectrum. We show how the Navier-Stokes equation for flow through a narrowing can be turned into a Schrödinger type equation. The complex eigenvalues of the latter equation give the frequencies and decay rates of the vortices present in the whirling pattern. Our diagnosis is based on understanding the relation between features in the sound spectrum and the severity of the narrowing. Today the most commonly used method of diagnosis is duplex ultrasound. In a small clinical trial our method appears to be as good as duplex ultrasound.
PARTICLE STATISTICS: A RESOURCE FOR QUANTUM INFORMATION PROCESSING
Authors: OMAR YASSER
Published: December 2006

In this article, we will show how particle statistics can be used as a resource for quantum information processing. After introducing this fundamental aspect of quantum physics, we will present several examples showing how it is possible to perform both useful and efficient quantum information processing relying only on the effects of the indistinguishability of identical particles. All the proposed schemes can be implemented with current technology.
QUANTUM COMPUTER: HOW FEASIBLE IS THE IDEA?
Authors: KWEK L. C. , EKERT ARTUR
Published: December 2006

The need for increased memory space and higher speed in computers has fueled the demand for smaller and faster computers. However, as the computer chips miniaturize, it becomes inevitable that we need to look at the possibility of manipulating and addressing atoms and molecules individually. One such possibility is a feasibility study of a quantum computer. In this report, we summarize some of the progress made in experimental realization of quantum computer in the last few years.
A preprogalanin cDNA from the turtle pituitary and regulation of its gene expression
Authors: Yu John Yuh-Lin , Pon Chin-Hon , Ku Hui-Chen , Wang Chih-Ting , Kao Yung-Hsi
Published: December 2006

Galanin is a hormone 29 or 30 amino acids (aa) long that is widely distributed within the body and exerts numerous biological effects in vertebrates. To fully understand its physiological roles in reptiles, we analyzed preprogalanin cDNA structure and expression in the turtle pituitary. Using the Chinese soft-shell turtle ( Pelodiscus sinensis order Testudines), we obtained a 672-base pair (bp) cDNA containing a 99-bp 5′-untranslated region, a 324-bp preprogalanin coding region, and a 249-bp 3′-untranslated region. The open-reading frame encoded a 108-aa preprogalanin protein with a putative 23-aa signal sequence at the NH2 terminus. Based on the location of putative Lys-Arg dibasic cleavage sites and an amidation signal of Gly-Lys-Arg, we propose that turtle preprogalanin is processed to yield a 29-aa galanin peptide with Gly1 and Thr29 substitutions and a COOH-terminal amidation. Sequence comparison revealed that turtle preprogalanin and galanin-29 had 48–81% and 76–96% aa identities with those of other vertebrates, respectively, suggesting their conservative nature. Expression of the turtle galanin gene was detected in the pituitary, brain, hypothalamus, stomach, liver, pancreas, testes, ovaries, and intestines, but not in the adipose or muscle tissues, suggesting tissue-dependent differences. An in vitro study that used pituitary tissue culture indicated that treatment with 17β-estradiol, testosterone, or gonadotropin-releasing hormone resulted in increased galanin mRNA expression with dose- or time-dependent differences, whereas leptin and neuropeptide Y reduced galanin mRNA levels. These results suggest a hormone-dependent effect on hypophyseal galanin mRNA expression.
Peak vs. total reactive hyperemia: which determines the magnitude of flow-mediated dilation?
Authors: Pyke Kyra E. , Tschakovsky Michael E.
Published: December 2006

We investigated the independent contributions of the peak and continued reactive hyperemia on flow-mediated dilation (FMD). 1) For the duration manipulation experiment (DME), 10 healthy males experienced reactive hyperemia durations of 10 s, 20 s, 30 s, 40 s, 50 s, or full reactive hyperemia (RH). 2) For the peak manipulation experiment (PME), eight healthy males experienced reactive hyperemia trials with three peak shear rate magnitudes (large, medium, and small). Data are means ± SD. For the DME, peak shear rate was not different between trials ( P = 0.326). Shear rate area under the curve (AUC) was P < 0.001. Peak %FMD was dependent on shear rate AUC: 10 s, 2.7 ± 1.3; 20 s, 6.2 ± 1.9; 30 s, 7.9 ± 2.9; 40 s, 8.3 ± 3.2; 50 s, 7.9 ± 3.2; full RH, 9.3 ± 4.1, with 10 and 20 s less than full RH ( P < 0.001). For the PME, peak shear rate was different between trials (large, 1,049.1 ± 285.8; medium, 726.4 ± 228.8; small, 512.8 ± 161.8; P < 0.001). AUC of the continued shear rate was not ( P = 0.412). Peak %FMD was unaffected by peak shear rate (large, 7.0 ± 2.7%; medium, 7.4 ± 2.6%; small, 6.6 ± 1.8%; P = 0.542). Peak and AUC shear stimulus were not significantly related in full RH ( r2 = 0.35, P = 0.07). We conclude that the shear stimulus AUC, not the peak itself, is the critical determinant of the peak FMD response. This indicates AUC as the best method of quantifying reactive hyperemia shear stimulus for %FMD normalization.
Therapeutic interactions between stathmin inhibition and chemotherapeutic agents in prostate cancer
Authors: Mistry Sucharita J. , Atweh George F.
Published: December 2006

Limitations of prostate cancer therapy may be overcome by combinations of chemotherapeutic agents with gene therapy directed against specific proteins critical for disease progression. Stathmin is overexpressed in many types of human cancer, including prostate cancer. Stathmin is one of the key regulators of the microtubule network and the mitotic spindle and provides an attractive therapeutic target in cancer therapy. We recently showed that adenovirus-mediated gene transfer of anti-stathmin ribozyme could suppress the malignant phenotype of prostate cancer cells in vitro. In the current studies, we asked whether the therapeutic effects of stathmin inhibition could be further enhanced by exposure to different chemotherapeutic agents. Exposure of uninfected LNCaP human prostate cancer cells or cells infected with a control adenovirus to Taxol, etoposide, 5-fluorouracil (5-FU), or Adriamycin resulted in modest decrease in proliferation and clonogenicity. Interestingly, exposure of cells infected with an anti-stathmin adenovirus to Taxol or etoposide resulted in a complete loss of proliferation and clonogenicity, whereas exposure of the same cells to 5-FU or Adriamycin potentiated the growth-inhibitory effects of the anti-stathmin ribozyme, but the cells continued to proliferate. Terminal deoxynucleotidyl transferase–mediated dUTP nick end labeling analysis of uninfected cells or cells infected with a control adenovirus showed modest induction of apoptosis in the presence of different drugs. In contrast, cells infected with the anti-stathmin adenovirus showed a marked increase in apoptosis on exposure to Taxol or etoposide and a modest increase on exposure to 5-FU or Adriamycin. Overall, the effects of combinations of anti-stathmin ribozyme with Taxol or etoposide were synergistic, whereas the effects of combinations of anti-stathmin ribozyme with 5-FU or Adriamycin were additive. Moreover, triple combination of anti-stathmin ribozyme with low noninhibitory concentrations of Taxol and etoposide resulted in a profound synergistic inhibition of proliferation, clonogenicity, and marked induction of apoptosis. This synergy might be very relevant for the treatment of prostate cancer because Taxol and etoposide are two of the most effective agents in this disease. Thus, this combination may provide a novel form of prostate cancer therapy that would avoid toxicities associated with the use of multiple chemotherapeutic agents at full therapeutic doses. [Mol Cancer Ther 2006;5(12):3248–57]
Effects of Calcium on the Erosive Potential of Acidic Candies in Saliva
Authors: Jensdottir T. , Nauntofte B. , Buchwald C. , Bardow A.
Published: December 2006

Theoretical calculations have shown that acidic candies may be potentially erosive upon consumption. However, little is known about the protective effect of adding calcium to potentially erosive candies and about the protective effects of saliva that cannot be fully accounted for by theoretical calculations. Therefore, the aims of this study were to (1) determine the erosive potential of acidic candies with and without calcium and (2) to determine differences between theoretically calculated erosive potential and actual erosive potential in saliva. Twenty healthy test persons sucked acidic candy with and without calcium while their whole saliva was collected into a closed system at different times: baseline, candy-stimulated, and post-stimulated. The erosive potential of the candy was evaluated from candy-induced changes in saliva degree of saturation with respect to hydroxyapatite (HAp) and directly by dissolution of HAp crystals in candy-stimulated saliva. The results showed that similar salivary stimulation was obtained with both candies. The modified candy released more than 13 mmol/l of calcium into saliva, resulting in a lower critical pH, and considerably lower erosive potential than the control (p < 0.001). Although a significant correlation was obtained between theoretical calculation of DSHAp and dissolution of HAp crystals (rs = 0.65; p < 0.001), many samples obtained by sucking modified candy showed no signs of HAp dissolution in spite of being undersaturated. We conclude that saturation levels and critical pH may not fully reflect when dental erosion is expected to occur in saliva and that calcium addition reduces the erosive potential of acidic candies.
Serum Prostate-Specific Antigen Levels in Middle Eastern Men with Subclinical Prostatitis
Authors: Anim J.T. , Kehinde E.O. , Sheikh M.A. , Prasad A. , Mojiminiyi O.A. , Ali Y. , Al-Awadi K.A.
Published: December 2006

Objective: To investigate the influence of subclinical or histologically diagnosed prostatitis on serum prostate-specific antigen (PSA) in patients investigated for prostatic disease in Kuwait. Materials and Methods: Serum PSA was assayed in patients investigated for prostatic disease in Mubarak Al-Kabeer Hospital, Kuwait, between December 2002 and December 2004. These included patients undergoing transrectal ultrasound with needle biopsy of the prostate gland and those who were treated with transurethral resection of the prostate or retropubic prostatectomy. The tissue was evaluated for prostatitis as well as the underlying disease, and the type and severity of prostatitis were compared with levels of serum PSA. Results: Of the 331 tissue specimens, 18 (5.4%) did not show prostatitis, while 233 (70.4%) with benign prostate and 80 (24.2%) with malignant prostate disease showed prostatitis. Of 270 men with known serum PSA levels, 198 and 72 had benign and malignant prostate disease, respectively. Of the 198, 77 (41%) with benign prostate disease and prostatitis and of the 72, 52 (76%) with malignant prostate disease and prostatitis had serum PSA levels >10 ng/ml. Conclusion: The data showed that although raised serum PSA is more commonly associated with prostate cancer, subclinical prostatitis is a significant source of high serum PSA in over 40% of men in Kuwait. That local factors may obscure the usefulness of serum PSA as a screening tool suggests the need for a locally applicable paradigm to identify prostate cancer.
Projections to the Preoptic Area from the Paraventricular Nucleus, Arcuate Nucleus and the Bed Nucleus of the Stria Terminalis Are Unlikely to Be Involved in Stress-Induced Suppression of GnRH Secretion in Sheep
Authors: Rivalland Elizabeth T.A. , Tilbrook Alan J. , Turner Anne I. , Iqbal Javed , Pompolo Sueli , Clarke Iain J.
Published: December 2006

Stress compromises reproductive function and the major physiological system activated during stress is the hypothalamo-pituitary-adrenal axis. Corticotrophin-releasing hormone and arginine vasopressin (AVP), which are produced in neurones of the paraventricular nucleus (PVN), drive the hypothalamo-pituitary-adrenal axis and are also implicated in the suppression of the reproductive axis. We used retrograde tracing and Fos labelling to map the projections from the PVN to the preoptic area (POA) where most gonadotrophin releasing hormone (GnRH) neurones are found. Fluorogold (FG) injections were made into the POA of gonadectomised male and female sheep (n = 5/sex), the animals were stressed and the brains recovered for histochemistry. All animals responded to stress with an increase in the number of Fos-labelled nuclei in the PVN. Few retrogradely labelled cells of the PVN were activated by stress. Dual labelling showed that very few FG-labelled cells also stained for corticotrophin-releasing hormone, none for AVP or enkephalin. Dual labelling for FG and Fos in the bed nucleus of the stria terminalis (BNST) and the arcuate nucleus showed that no FG-labelled cells in the BNST and only few in the ARC were activated by stress. No sex differences were observed in the activation of FG-labelled cells in any of the nuclei examined. We conclude that, although cells of the PVN, BNST and/or arcuate nucleus may affect reproduction via the GnRH cells of the POA, this is unlikely to involve direct input to the POA. If cells of these regions are involved in GnRH suppression during stress, this may occur via interneuronal pathways.
Antibodies to Periodontal Organisms Are Associated with Decreased Kidney Function
Authors: Kshirsagar Abhijit V. , Offenbacher Steven , Moss Kevin L. , Barros Silvana P. , Beck James D.
Published: December 2006

Background/Aims: Increasing evidence suggests that clinical signs of periodontal disease are independently associated with renal impairment. However, no studies have examined the possible linkage of kidney disease with serum antibody to oral pathogens. Methods: The periodontal disease status was assessed in an older community-dwelling population (Dental Atherosclerosis Risk in Communities) to include: clinical measurements; oral biofilm microbial composition by DNA checkerboard, and serum antibody immunoglobulin-γ (IgG) titers to specific bacteria by immunocheckerboard. Baseline characteristics were used to compute estimated glomerular filtration rate defining eGFR <60 ml/min/1.73 m2 as impaired renal function in 103 of 5,032 subjects. Levels of serum IgG to specific oral bacteria were categorized by quartiles (comparing upper vs. lower three) as high titer and GFR <60 as the dependent variable in logistic regression models, adjusting for multiple comparisons (Hotelling T2) and traditional risk factors including age, race, smoking, diabetes, hypertension, body mass, waist-to-hip ratio, serum triglycerides, HDL, and LDL cholesterol. Results: High levels of serum IgG to selected periodontal pathogens including Porphyromonas gingivalis, Treponema denticola and Aggregobacter actinomycetemcomitans were associated with an increased odds for GFR <60 ml/min/1.73 m2, adjusted odds ratio ranging from 1.6 to 1.8 and p < 0.05. Conclusions: Elevated IgG to periodontal pathogens is significantly associated with impaired kidney function, independent of traditional risk factors. Prospective studies are necessary to confirm these findings.
Hyperbaric Oxygen in Tinnitus: Influence of Psychological Factors on Treatment Results?
Authors: Porubsky C. , Stiegler P. , Matzi V. , Lipp C. , Kontaxis A. , Klemen H. , Walch C. , Smolle-Jüttner F.
Published: December 2006

Introduction: The standard treatment of subjective tinnitus hardly reaches the level of placebo controls. Though the effectiveness of hyperbaric oxygenation (HBO) for subjective tinnitus has never been objectified, it is still advocated by some institutions. We analyzed the effectiveness of hyperbaric oxygen treatment in the context of accompanying factors. Patients and Methods: We randomized 360 patients suffering from tinnitus into 2 HBO treatment protocols (group A: 2.2 bar for 60 min bottom time and group B: 2.5 bar for 60 min bottom time once a day for 15 days). All patients were asked to fill in a questionnaire (social and medical history, tinnitus characteristics, pre-HBO duration of tinnitus, prior therapy, pretreatment expectation, accompanying symptoms). A subjective assessment of the therapeutic effect was obtained. Results: Twelve patients (3.3%) experienced complete remission of tinnitus, in 122 (33.9) the intensity lessened, and 44 (12.2%) had a subjectively agreeable change of noise characteristics. No change was found in 157 cases (43.6%) and 25 (6.9%) experienced deterioration. There was no statistically significant difference between groups A and B (p > 0.05). Out of 68 patients with a positive expectation of HBO effects, 60.3% stated that the tinnitus had improved whereas only 47.2 and 19%, respectively, out of patients who underwent therapy with an indifferent (n = 271) or negative expectation (n = 21) reported an improvement. The influence of subjective expectation on the outcome was statistically significant (p < 0.05). Conclusion: The therapeutic effects of HBO on subjective tinnitus may be substantially influenced by psychological mechanisms.
Serum Nitrite/Nitrate and Arginase Levels in Patients with Allergic Rhinitis
Authors: Ünal Murat , Eskandari Hatice Gülçin , Erçetin Neslihan , Doğruer Zeynep Nil , Pata Yavuz Selim
Published: December 2006

Nitric oxide (NO) plays an important role in the regulation of upper respiratory function. Patients with untreated allergic rhinitis (AR) have an increased level of NO in the nasal cavity compared to normal individuals. We aimed to investigate serum levels of arginase and NO metabolites nitrite/nitrate in patients with AR during the symptomatic period. The patient and control groups consisted of 14 males and 12 females (mean age: 29, range: 20–40 years), and 10 males and 10 females (mean age: 27, range: 22–38 years), respectively. Nitrite/nitrate levels were 0.98 ± 0.33 ng/ml in the patients with AR, and 0.78 ± 0.26 ng/ml in the control group (p = 0.03). Arginase levels were 28.8 ± 14.1 ng/ml in the patients with AR, and 20.8 ± 13.5 ng/ml in the control group. The difference between the groups was statistically insignificant (p = 0.24). Our results support the view that NO plays an important role in the pathogenesis of AR, and NO metabolites may be used as a marker for monitoring the disease activity and therapy.
Perioperative Predictors of Successful Hysteroscopic Endometrial Ablation
Authors: Gemer Ofer , Kruchkovich Jenya , Huerta Michael , Kapustian Viki , Kroll Dov , Anteby Eyal
Published: December 2006

Objective: To determine which perioperative factors influence the success of hysteroscopic endometrial ablation in patients with menorrhagia. Study Design: A longitudinal study of 128 women who underwent hysteroscopic endometrial ablation or resection. Clinical data included age, uterine size, the presence of intramural or submucosal myomas and polyps, and length of follow-up from initial hysteroscopic ablation to re-ablation or hysterectomy (‘failure’). Kaplan-Meier survival analysis, log-rank tests and Cox proportional hazard regression were used to evaluate the equality of survival distributions and to model the overall effects of the various predictor variables on surgical outcomes. Results: Patients were followed for a median time of 44 months. Thirteen women (10.2%) underwent a second operative procedure. Multivariate analysis identified submucosal myoma as a statistically significant positive predictor of the risk of failure [hazard ratio (HR) 5.22, 95% confidence interval (CI) = 1.63, 16.73)]. Older age was associated with a marginally lower risk of subsequent surgery (HR 0.90 per additional year of age, 95% CI = 0.81, 1.00). Conclusions: The presence of submucosal myoma increases the risk of subsequent surgery in patients undergoing endometrial ablation.
Incidence of Multiple Sclerosis among First Nations People in Alberta, Canada
Authors: Warren Sharon , Svenson Lawrence W. , Warren Kenneth G. , Metz Luanne M. , Patten Scott B. , Schopflocher Donald P.
Published: December 2006

Multiple sclerosis (MS) is thought to be rare among North American aboriginals, although few population-based frequency studies have been conducted. Data from government health databases were used to describe the incidence of MS among First Nations aboriginal people in the province of Alberta compared to the general population from 1994 to 2002. The general population rates were consistently higher than First Nations rates, but were essentially stable across this time span for both groups. For First Nations the MS incidence was 7.6 per 100,000 and 20.6 per 100,000 for the general population in 2002. During 2000–2002 for First Nations the incidence was 12.7 for females and 7.6 for males, with a female-to-male ratio of 1.7:1. During the same period the general population incidence was 32.2 for females and 12.7 for males, with a female-to-male ratio of 2.5:1. The peak incidence for both First Nations and the general population of Alberta was in the age group 30–39 years in 2002. The high incidence rates are consistent with high prevalence rates reported for both groups in 2002: 99.9 per 100,000 for First Nations and 335.0 per 100,000 for the general population. While the MS incidence in First Nations people is lower than in the general population of Alberta, it is not rare by worldwide standards.
Patterns and Correlates of Muscle Strength Loss in Older Women
Authors: Forrest Kimberly Y.Z. , Zmuda Joseph M. , Cauley Jane A.
Published: December 2006

Background: The aging process is associated with progressive declines in muscle strength, resulting in functional disability and reduced quality of life. Objective: The purpose of this epidemiological study was to examine the age-related loss of grip strength both cross-sectionally and longitudinally and the risk factors associated with the decline in muscle strength in a large population of community-living older women (aged 65–91 years). Methods: Clinical visits, including physical examinations and lifestyle assessment, were conducted at baseline and biennially afterwards for a total of 10 years of follow-up. The upper-body muscle strength was measured by grip strength using a hand-held dynamometer. Results: The muscle strength decreased cross-sectionally (n = 9,372) as well as longitudinally (n = 5,214), as age increased, and the decline in muscle strength measured during follow-up was greater than that measured cross-sectionally at baseline. The average loss of grip strength during 10 years of follow-up was 5.1 kg, equivalent to a rate of 2.4% decline per year, with the greatest loss seen in the oldest age group (80 years or older). Cross-sectional analysis revealed that the correlates of lower muscle strength included older age, greater weight, greater height loss since age 25 years, lower protein intake, difficulties in functional tasks, and lower physical activity. In longitudinal analysis, older age, baseline strength, weight and height loss during follow-up, difficulties in functional tasks, and lower physical activity were found to be significantly and independently associated with greater loss in grip strength during follow-up. Conclusions: Cross-sectional and longitudinal analyses of age-related loss of muscle strength yielded different rates of decline. In addition to older age and difficulties in functional tasks, a number of modifiable factors, including weight and physical activity, are associated with increased decline in muscle strength among older women.
Granulocyte Macrophage Colony-Stimulating Factor Regulates Dendritic Cell Content of Atherosclerotic Lesions
Authors: Shaposhnik Zory , Wang Xuping , Weinstein Michael , Bennett Brian J. , Lusis Aldons J.
Published: December 2006

Objective—Recent evidence suggests that dendritic cells may play an important role in atherosclerosis. Based primarily on previous in vitro studies, we hypothesized that granulocyte macrophage colony-stimulating factor (GM-CSF)-deficient mice would have decreased dendritic cells in lesions.

Methods and Results—To test this, we characterized gene targeted GM-CSF−/−mice crossed to hypercholesterolemic low-density lipoprotein receptor null mice. Our results provide conclusive evidence that GM-CSF is a major regulator of dendritic cell formation in vivo. Aortic lesion sections in GM-CSF−/−low-density lipoprotein receptor null animals showed a dramatic 60% decrease in the content of dendritic cells as judged by CD11c staining but no change in the overall content of monocyte-derived cells. The GM-CSF–deficient mice exhibited a significant 20% to 50% decrease in the size of aortic lesions, depending on the location of the lesions. Other prominent changes in GM-CSF−/−mice were decreased lesional T cell content, decreased autoantibodies to oxidized lipids, and striking disruptions of the elastin fibers adjacent to the lesion.

Conclusion—Given that GM-CSF is dramatically induced by oxidized lipids in endothelial cells, our data suggest that GM-CSF serves to regulate dendritic cell formation in lesions and that this, in turn, influences inflammation, plaque growth and possibly plaque stability.
Vascular Endothelial Growth Factor Synergistically Enhances Induction of E-Selectin by Tumor Necrosis Factor-α
Authors: Stannard Anita K. , Khurana Rohit , Evans Ian M. , Sofra Vassiliki , Holmes David I.R. , Zachary Ian
Published: December 2006

Objective—

The regulation of endothelial cell adhesion molecules (CAMs) by vascular endothelial growth factor (VEGF) was investigated in cell cultures and in a rabbit model of atherogenic neointima formation.

Methods and Results—

VEGF regulation of vascular CAM-1 (vascular cell adhesion molecule), intercellular CAM-1 (intercellular adhesion molecule), and E-selectin were investigated in human umbilical vein endothelial cells using quantitative polymerase chain reaction, enzyme-linked immunosorbent assay, and flow cytometry, and in the rabbit collar model of atherogenic macrophage accumulation by immunostaining. VEGF alone caused no significant induction of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, or E-selectin compared with tumor necrosis factor-α. In both hypercholesterolemic and normal rabbits, adenoviral VEGF-A
165
expression caused no increase in endothelial vascular cell adhesion molecule-1 or E-selectin. In contrast, pretreatment of human umbilical vein endothelial cells with VEGF significantly increased E-selectin expression induced by tumor necrosis factor-α, compared with tumor necrosis factor-α alone, whereas vascular cell adhesion molecule-1 and intercellular adhesion molecule-1 were unaffected. VEGF similarly enhanced IL-1β–induced E-selectin upregulation. VEGF also synergistically increased tumor necrosis factor-α–induced E-selectin mRNA and shedding of soluble E-selectin. Synergistic upregulation of E-selectin expression by VEGF was mediated via VEGF receptor-2 and calcineurin signaling.

Conclusions—

VEGF alone does not activate endothelium to induce CAM expression; instead, VEGF “primes” endothelial cells, sensitizing them to cytokines leading to heightened selective pro-inflammatory responses, including upregulation of E-selectin.
Improving Prediction of Ischemic Cardiovascular Disease in the General Population Using Apolipoprotein B
Authors: Benn Marianne , Nordestgaard Børge G. , Jensen Gorm Boje , Tybjærg-Hansen Anne
Published: December 2006

Background—

Apolipoprotein B (apoB) levels predict fatal myocardial infarction. Whether apoB also predicts nonfatal ischemic cardiovascular events is unclear. We tested the following hypotheses: apoB predicts ischemic cardiovascular events, and apoB is a better predictor of ischemic cardiovascular events than low-density lipoprotein cholesterol.

Methods and Results—

We studied 9231 asymptomatic women and men from the Danish general population followed prospectively for 8 years and observed the following incident events: ischemic heart disease 591, myocardial infarction 278, ischemic cerebrovascular disease 313, ischemic stroke 229, and any ischemic cardiovascular event 807. Women with apoB in the upper versus the lower tertile had hazard ratios for ischemic heart disease of 1.8 (1.2 to 2.5), for myocardial infarction 2.6 (1.4 to 4.7), and for any ischemic cardiovascular event 1.8 (1.3 to 2.3), and men had hazard ratios for ischemic heart disease of 1.9 (1.5 to 2.6), for myocardial infarction 2.4 (1.5 to 3.6), and for any ischemic cardiovascular event 1.6 (1.3 to 2.1). Women had similar hazard ratios for ischemic cerebrovascular disease and ischemic stroke. ApoB had a higher predictive ability than low-density lipoprotein cholesterol in the prediction of ischemic heart disease, myocardial infarction, any ischemic cardiovascular event, and any nonfatal ischemic cardiovascular event in both genders (
P
=0.03 to <0.001). Finally, in smokers older than 60 years with systolic blood pressure >160 mm Hg, apoB contributed 11% in women and 15% in men to the increase in absolute 10-year risk from the lower to the upper apoB tertile.

Conclusion—

ApoB predicts ischemic cardiovascular events in both genders, and is better than low-density lipoprotein cholesterol in this respect. We suggest that prediction of future ischemic cardiovascular events could be improved by measuring apoB.