bluuebunny/crossref_metadata_2025 huggingface dataset:
Social Fears in Adolescence
Authors: Cunha Marina , Gouveia José Pinto , do Céu Salvador Maria
Published: August 2008

This study describes the development, factor structure, psychometric properties, and validity of the Social Anxiety and Avoidance Scale for Adolescents (SAASA). Two subscales assessing discomfort and avoidance of typical social situations faced by adolescents constitute the SAASA. Both subscales revealed good internal consistency and temporal stability. Convergent validity was determined comparing the Social Anxiety and Avoidance Scale for Adolescents (SAASA) scores to Social Anxiety Scale for Adolescents scores (SAS-A), scores for general anxiety (Revised Childrens Manifest Anxiety Scale, RCMAS), and scores for depression (Childrens Depression Inventory, CDI) . Confirmatory factor analyses supported six distinct factors revealing different dimensions of social fears. The SAASA effectively discriminated between adolescents with social phobia with and without comorbid diagnoses, and adolescents with social phobia from adolescents with other anxiety disorders or without any disorder. These results suggest that the SAASA is a valid instrument to use in the clinical assessment and research on adolescent social phobia.
Meteor radar observations of short‐term tidal variabilities in the low‐latitude mesosphere‐lower thermosphere: Evidence for nonlinear wave‐wave interactions
Authors: Kumar Karanam Kishore , Deepa V. , Antonita T. Maria , Ramkumar Geeta
Published: August 2008

Short‐term tidal variabilities in the mesosphere‐lower thermosphere (MLT) region using the meteor radar observations over Trivandrum (8.5°N, 77°E) during March 2006 to February 2007 are discussed. Spectral analysis of daily‐averaged zonal and meridional winds revealed the presence of planetary waves, with periods ranging from ∼2 to 30 days in the height region of 82–98 km. The hourly zonal and meridional wind measurements are then used to estimate day‐to‐day diurnal tide amplitudes in the MLT region for the first time over this latitude. Spectral analysis of zonal and meridional diurnal tide amplitudes revealed tidal modulations at periods ranging from ∼2 to 30 days. Further, during a strong episode of tidal modulation, which is identified from the wavelet spectra, a group of subsidiary spectral components around the diurnal tide is observed. The presence of subsidiary spectral components around the diurnal tide has provided evidence for nonlinear interaction between tides and planetary waves. To substantiate this result, bispectral analysis is carried out, which showed the nonlinear tide‐planetary wave interactions by revealing the presence of secondary waves exactly at the anticipated periods. As the present observational site is very near to dip equator, it is envisaged that the present results will have important implications in interpreting day‐to‐day variabilities in the equatorial ionosphere.
Tipping calibration for digital gain compensative microwave radiometer and correction on antenna sidelobe influences
Authors: Song D. S. , Zhao K. , Guan Z.
Published: August 2008

The tipping curve calibration method has been an important calibration technique for ground‐based microwave radiometers that measure atmospheric water vapor and cloud liquid water. The method calibrates a radiometer system using the brightness temperatures at various viewing angles in the atmosphere. In this paper, the tipping calibration was carried out by digital gain compensative microwave radiometer (DGCMR) in Inner Mongolia, China, in August 2006. The frequencies of the radiometers are 23.8 and 31.65 GHz with rectangle horn and paraboloid antenna. Using the relationship between correction value and scanning angle, the brightness temperature of the antenna sidelobe contribution is corrected. The comparison of the correction results for the two antenna types shows that the antenna sidelobe error for the rectangular horn antenna can be corrected more effectively.
Depletion of nucleophosmin leads to distortion of nucleolar and nuclear structures in HeLa cells
Authors: Amin Mohammed Abdullahel , Matsunaga Sachihiro , Uchiyama Susumu , Fukui Kiichi
Published: August 2008

NPM (nucleophosmin; also known as B23) is an abundantly and ubiquitously expressed multifunctional nucleolar phosphoprotein, which is involved in numerous cellular processes, including ribosome biogenesis, protein chaperoning and centrosome duplication; however, the role of NPM in the cell cycle still remains unknown. In the present study, we show dynamic localization of NPM throughout the cell cycle of HeLa cells. Using a combination of RNAi (RNA interference) and three-dimensional microscopy we show that NPM is localized at the chromosome periphery during mitosis. We also demonstrate that depletion of NPM causes distortion of nucleolar structure as expected and leads to unexpected dramatic changes in nuclear morphology with multiple micronuclei formation. The defect in nuclear shape of NPM-depleted cells, which is clearly observed by live-cell imaging, is due to the distortion of cytoskeletal (α-tubulin and β-actin) structure, resulting from the defects in centrosomal microtubule nucleation. These results indicate that NPM is an essential protein not only for the formation of normal nucleolar structure, but also for the maintenance of regular nuclear shape in HeLa cells.
Nondestructive experimental determination of bimaterial rectangular cantilever spring constants in water
Authors: Snow David E. , Weeks Brandon L. , Kim Dae Jung , Pitchimani Rajasekar , Hope-Weeks Louisa J.
Published: August 2008

In order to address the issue of spring constant calibration in viscous fluids such as water, a new method is presented that allows for the experimental calibration of bimaterial cantilever spring constants. This method is based on modeling rectangular cantilever beam bending as a function of changing temperature. The temperature change is accomplished by heating water as it flows around the cantilever beams in an enclosed compartment. The optical static method of detection is used to measure the deflection of cantilever at the free end. Experimentally determined results are compared to Sader’s method and to the Thermotune method most commonly used in cantilever calibrations. Results indicate that the new bimaterial thermal expansion method is accurate within 15%–20% of the actual cantilever spring constant, which is comparable to other nondestructive calibration techniques.
Morphology of step structures on CeO2(111)
Authors: Torbrügge Stefan , Cranney Marion , Reichling Michael
Published: August 2008

The morphology of step structures on the CeO2(111) surface is studied by dynamic scanning force microscopy (SFM) operated in the noncontact mode. The surface exhibits hexagonal islands and pits of O–Ce–O triple layer height with steps mostly enclosing an angle of 120°. Atomically resolved images reveal that the (111) surface almost exclusively exhibits alternating steps having (110) and (001) facets. Kink sites and missing oxygen atoms at step edges are identified to be the dominating defective sites at step edges. It is demonstrated that low coordinated oxygen atoms at step edges can be removed by the scanning SFM tip.
Low-cost and high-gain silicide Schottky-barrier collector phototransistor integrated on Si waveguide for infrared detection
Authors: Zhu Shiyang , Lo G. Q. , Yu M. B. , Kwong D. L.
Published: August 2008

A two-terminal silicide Schottky-barrier collector phototransistor (SBCPT) integrated on a silicon-on-insulator waveguide was proposed and demonstrated using low-cost standard silicon processing technology. Owing to the current gain through the transistor action, the SBCPT at 5 V bias achieves a responsivity around 1550 nm of ∼150 mA/W, which is approximately 17.6-fold larger than the corresponding Schottky-barrier photodiode (SBPD) having the same silicide absorber. The current gain thereby the responsivity of SBCPT may be further improved simply by reducing the base width. Moreover, the SBCPT at negative bias exhibits a very low dark current of ∼12 pA owing to the presence of a reversely biased Si p-n junction while with the responsivity and speed only slightly degraded as compared to the SBPD counterpart. The proposed detector can be utilized as an in-line or terminal optical monitor in low-cost all-silicon electronic-photonic integrated circuits.
The high-pressure phase behavior and compressibility of 2,4,6-trinitrotoluene
Authors: Stevens Lewis L. , Velisavljevic Nenad , Hooks Daniel E. , Dattelbaum Dana M.
Published: August 2008

The phase stability and isothermal compression behavior of 2,4,6-trinitrotoluene (TNT) have been established to 26.5 GPa using angle-dispersive x-ray diffraction. P-V isotherms derived from the high-pressure x-ray spectra displayed a slight density hysteresis around 4.0 GPa and a sharp discontinuity at ∼20.0 GPa. The latter transition is ascribed to a monoclinic-to-orthorhombic first-order phase transition in TNT. The conversion of the isothermal P-V data to the shock velocity-particle velocity plane revealed a deviation from linearity at low up, a cusp associated with the phase transition at high up, and general agreement with the wealth of unreacted Hugoniot data on TNT.
Capacitance characteristics of phase separated La0.5Ca0.5MnO3∕Nb–SrTiO3 p-n junction
Authors: Xie B. T. , Zhao Y. G. , Xiong C. M.
Published: August 2008

The capacitance characteristics of La0.5Ca0.5MnO3∕Nb–SrTiO3 p-n junction and magnetic property have been investigated. The magnetic field-induced increase in ferromagnetic metallic phase, irreversibility, and the exchange bias effect were observed. The junction also shows a remarkable thermal hysteresis of capacitance, a giant positive magnetocapacitance (MC), a remarkable difference of MC for the zero field cooling and field cooling processes, and a memory effect of magnetic field. The results can be understood in terms of phase separation. This work demonstrates the remarkable tunability of the capacitance for phase separated manganite heterojunctions, which may have potential applications.
Optimized photocathode for spin-polarized electron sources
Authors: Mamaev Yu. A. , Gerchikov L. G. , Yashin Yu. P. , Vasiliev D. A. , Kuzmichev V. V. , Ustinov V. M. , Zhukov A. E. , Mikhrin V. S. , Vasiliev A. P.
Published: August 2008

Photocathode for highly polarized electron emission has been developed, fabricated, and studied. The photocathode is based on short-period strained AlInGaAs∕AlGaAs superlattice grown by molecular beam epitaxy. Deformation of AlInGaAs quantum well results in 87meV energy splitting between heavy hole and light hole minibands. Electron emission from the developed photocathode demonstrates maximal polarization of 92% with quantum efficiency of 0.85% at room temperature.
Potential landscape and flux framework of nonequilibrium networks: Robustness, dissipation, and coherence of biochemical oscillations
Authors: Wang Jin , Xu Li , Wang Erkang
Published: August 2008

We established a theoretical framework for studying nonequilibrium networks with two distinct natures essential for characterizing the global probabilistic dynamics: the underlying potential landscape and the corresponding curl flux. We applied the idea to a biochemical oscillation network and found that the underlying potential landscape for the oscillation limit cycle has a distinct closed ring valley (Mexican hat-like) shape when the fluctuations are small. This global landscape structure leads to attractions of the system to the ring valley. On the ring, we found that the nonequilibrium flux is the driving force for oscillations. Therefore, both structured landscape and flux are needed to guarantee a robust oscillating network. The barrier height separating the oscillation ring and other areas derived from the landscape topography is shown to be correlated with the escaping time from the limit cycle attractor and provides a quantitative measure of the robustness for the network. The landscape becomes shallower and the closed ring valley shape structure becomes weaker (lower barrier height) with larger fluctuations. We observe that the period and the amplitude of the oscillations are more dispersed and oscillations become less coherent when the fluctuations increase. We also found that the entropy production of the whole network, characterizing the dissipation costs from the combined effects of both landscapes and fluxes, decreases when the fluctuations decrease. Therefore, less dissipation leads to more robust networks. Our approach is quite general and applicable to other networks, dynamical systems, and biological evolution. It can help in designing robust networks.
An engineered selenocysteine defines a unique class of antibody derivatives
Authors: Hofer Thomas , Thomas Joshua D. , Burke Terrence R. , Rader Christoph
Published: August 2008

Selenocysteine is cotranslationally inserted into proteins by recoding the stop codon UGA from termination to selenocysteine insertion. The nucleophilic selenol group of selenocysteine endows this rare amino acid with unique chemical reactivity that allows regiospecific covalent conjugation in the presence of the other natural amino acids. Using a mammalian expression system, we generated an IgG1-derived Fc fragment with a C-terminal selenocysteine in yields comparable to conventional monoclonal antibodies and conjugated it to an electrophilic derivative of a peptidomimetic that binds with high affinity and specificity to integrin α4β1. Through this conjugation, both the biological and chemical components are endowed with pharmacological advantages. We demonstrate that whereas the Fc protein increases the circulatory half-life from minutes to days and mediates transcytosis through binding to the neonatal Fc receptor, the peptidomimetic introduces cross-species binding to cell surface integrin α4β1and blocks its interaction with vascular cell adhesion molecule-1. Compared with conventional monoclonal antibodies, our technology benefits economically from combining a generic biological component with a variable chemical component.
The
H19
locus acts
in vivo
as a tumor suppressor
Authors: Yoshimizu Tomomi , Miroglio Audrey , Ripoche Marie-Anne , Gabory Anne , Vernucci Maria , Riccio Andrea , Colnot Sabine , Godard Cécile , Terris Benoit , Jammes Hélène , Dandolo Luisa
Published: August 2008

The
H19
locus belongs to a cluster of imprinted genes that is linked to the human Beckwith-Wiedemann syndrome. The expression of
H19
and its closely associated
IGF2
gene is frequently deregulated in some human tumors, such as Wilms' tumors. In these cases, biallelic
IGF2
expression and lack of expression of
H19
are associated with hypermethylation of the imprinting center of this locus. These observations and others have suggested a potential tumor suppressor effect of the
H19
locus. Some studies have also suggested that
H19
is an oncogene, based on tissue culture systems. We show, using
in vivo
murine models of tumorigenesis, that the
H19
locus controls the size of experimental teratocarcinomas, the number of polyps in the
Apc
murine model of colorectal cancer and the timing of appearance of SV40-induced hepatocarcinomas. The
H19
locus thus clearly displays a tumor suppressor effect in mice.
Resolving voltage-dependent structural changes of a membrane photoreceptor by surface-enhanced IR difference spectroscopy
Authors: Jiang X. , Zaitseva E. , Schmidt M. , Siebert F. , Engelhard M. , Schlesinger R. , Ataka K. , Vogel R. , Heberle J.
Published: August 2008

Membrane proteins are molecular machines that transport ions, solutes, or information across the cell membrane. Electrophysiological techniques have unraveled many functional aspects of ion channels but suffer from the lack of structural sensitivity. Here, we present spectroelectrochemical data on vibrational changes of membrane proteins derived from a single monolayer. For the seven-helical transmembrane protein sensory rhodopsin II, structural changes of the protein backbone and the retinal cofactor as well as single ion transfer events are resolved by surface-enhanced IR difference absorption spectroscopy (SEIDAS). Angular changes of bonds versus the membrane normal have been determined because SEIDAS monitors only those vibrations whose dipole moment are oriented perpendicular to the solid surface. The application of negative membrane potentials (ΔV = −0.3 V) leads to the selective halt of the light-induced proton transfer at the stage of D75, the counter ion of the retinal Schiff base. It is inferred that the voltage raises the energy barrier of this particular proton-transfer reaction, rendering the energy deposited in the retinal by light excitation insufficient for charge transfer to occur. The other structural rearrangements that accompany light-induced activity of the membrane protein, are essentially unaffected by the transmembrane electric field. Our results demonstrate that SEIDAS is a generic approach to study processes that depend on the membrane potential, like those in voltage-gated ion channels and transporters, to elucidate the mechanism of ion transfer with unprecedented spatial sensitivity and temporal resolution.
TRPV4 channel participates in receptor-operated calcium entry and ciliary beat frequency regulation in mouse airway epithelial cells
Authors: Lorenzo Ivan M. , Liedtke Wolfgang , Sanderson Michael J. , Valverde Miguel A.
Published: August 2008

The rate of mucociliary clearance in the airways is a function of ciliary beat frequency (CBF), and this, in turn, is increased by increases in intracellular calcium. The TRPV4 cation channel mediates Ca
2+
influx in response to mechanical and osmotic stimuli in ciliated epithelia. With the use of a TRPV4-deficient mouse, we now show that TRPV4 is involved in the airways' response to physiologically relevant physical and chemical stimuli. Ciliary TRPV4 expression in tracheal epithelial cells was confirmed with immunofluorescence in TRPV4
+/+
mice. Ciliated tracheal cells from TRPV4
−/−
mice showed no increases in intracellular Ca
2+
and CBF in response to the synthetic activator 4α-phorbol 12,13-didecanoate (4αPDD) and reduced responses to mild temperature, another TRPV4-activating stimulus. Autoregulation of CBF in response to high viscosity solutions is preserved in TRPV4
−/−
despite a reduced Ca
2+
signal. More interestingly, TRPV4 contributed to an ATP-induced increase in CBF, providing a pathway for receptor-operated Ca
2+
entry but not store-operated Ca
2+
entry as the former mechanism is lost in TRPV4
−/−
cells. Collectively, these results suggest that TRPV4 is predominantly located in the cilia of tracheal epithelial cells and plays a key role in the transduction of physical and chemical stimuli into a Ca
2+
signal that regulates CBF and mucociliary transport. Moreover, these studies implicate the participation of TRPV4 in receptor-operated Ca
2+
entry.
Interaction between connexin35 and zonula occludens-1 and its potential role in the regulation of electrical synapses
Authors: Flores Carmen E. , Li Xinbo , Bennett Michael V. L. , Nagy James I. , Pereda Alberto E.
Published: August 2008

Although regulation of chemical transmission is known to involve the interaction of receptors with scaffold proteins, little is known about the existence of protein–protein interactions in regulating gap junction-mediated electrical synapses. The scaffold protein zonula-occludens-1 (ZO-1), a member of the MAGUK family of proteins, was reported to interact with several connexins (Cxs). We show here that ZO-1 extensively colocalizes with Cx35 at identifiable “mixed” (electrical and chemical) contacts on goldfish Mauthner cells, a model synapse for the study of vertebrate electrical transmission where it is possible to correlate physiological properties with molecular composition. Further, our analysis indicates that these proteins directly interact at goldfish electrical synapses. In contrast to Cx43, which interacts with ZO-1 via the PDZ2 domain, Cx35 interacts with ZO-1 via the PDZ1 domain, and this association is of lower affinity. The properties of the ZO-1/Cx35 association suggest the existence of a more dynamic relation between these two proteins, possibly including a role of ZO-1 in regulating gap junctional conductance at these highly modifiable electrical synapses. The interaction of ZO-1 with conserved regions of the C termini of Cx35/Cx36 orthologs may have a common function at electrical synapses of mammals and other vertebrates.
Neutralization of HIV-1 by redirection of natural antibodies
Authors: Perdomo Maria F. , Levi Michael , Sällberg Matti , Vahlne Anders
Published: August 2008

The great variability and high glycosylation of gp120 poses a great challenge for the design of a functional immune therapy. The binding region of the CD4 receptor to gp120, however, is well conserved and may constitute a target to limit viral entry and infectivity. Our strategy consists in using a preexisting pool of natural antibodies directed toward the gal(α1,3)gal disaccharide and to redirect it to HIV. We here show that using CD4-derived, gp120-binding, synthetic peptides chemically linked to gal(α1,3)gal can redirect these natural antibodies and improve the HIV-1 neutralizing activity of the CD4-derived peptides
in vitro
. Importantly, the binding of the CD4-gal(α1,3)gal peptides to HIV-1–infected cells conferred antibody-dependent cellular cytotoxicity after the addition of human sera. Thus, the temporary redirection of naturally occurring antibodies and their biological activities to a new antigen represents a completely new way of targeting a human disease.
Longitudinal evaluation of the occurrence of MRI-detectable bone marrow edema in osteoarthritis of the knee
Authors: Brem M. H. , Schlechtweg P. M. , Bhagwat J. , Genovese M. , Dillingham M. F. , Yoshioka H. , Lang P.
Published: August 2008

Background: Bone marrow edema (BME) is a condition detectable with magnetic resonance imaging (MRI) and is present in different stages of osteoarthritis (OA). Its pathogenesis is still not completely known.

Purpose: To evaluate the longitudinal occurrence and persistence of BME in early OA of the knee.

Material and Methods: Twenty-three patients (eight females, 15 males; mean age 55.5±10.3 years) were scanned with a 1.5T MR imaging unit (sagittal fat-suppressed intermediate-weighted fast spin echo; 4-mm section thickness, 1-mm intersection gap, 256x192 matrix, 120-mm field of view). Images were obtained in all 23 patients at two time points (TPs) and in 12 patients at three TPs. Images were evaluated by two readers independently; discrepancies in image grading were reviewed and evaluated in consensus. A four-point image-grading scale was used (absence of BME to severe BME). Four main anatomical regions were evaluated (medial femur, lateral femur, medial tibia, lateral tibia), which were subcategorized into anterior, central, and posterior regions.

Results: One hundred five areas of BME in the 23 patients were found at all three TPs. In 16 areas, the BME was consistent at the same location over time, in seven locations the BME became larger, in six areas the BME became smaller, and in 16 locations it could not be detected in follow-up MRIs. In one case, the BME was smaller at TP2 but increased at TP3. In eight cases, only at the last time point could a BME be detected.

Conclusion: BME is not a static phenomenon but changes over time. Correlation to physical activity and local inflammatory reaction should be evaluated.
Spectroscopic, thermal and X-ray powder diffraction patterns of Bi(V) complexes with [2S-[2α, 5α, 6β(S*)]-6-[amino(4-hydroxyphenyl) acetylamino]-3, 3-dimethyl-7-oxo-4-thia-1-azabicyclo[3,2,0] hepatane-2-carboxylic acid and (6R)-6-(α-phenyl-D-glycyamino) penicillinic acids
Authors: Kumar Rajiv , Mishra Parashuram
Published: August 2008

Novel Bi(V) complexes with the β-lactam antibiotics amoxicillin trihydrate (ACT) and ampicillin trihydrate (APT) ligands were prepared and studied by several spectral techniques both in solid as well in solution. The crystallographic data of the ligands and their relative complexes are given as a = 13.9961 (A), b = 5.1569(A) c = 4.4571 (A) for ACT; a = 21.45352 (A), b = 21.45352 (A) c = 4.57137, z = 2 for Bi-ACT; a = 19.051 (A), b = 15.4799 (A) c = 6.67522 (A) for APT; and a = 22.24866 (A), b = 4.254743 (A), c = 12.08440 (A) for Bi-APT. The thermodynamic parameters ΔE*, ΔH*, ΔS*, ΔG* and K, were determined and have a good agreement with the X-ray powder diffraction data.
1H NMR, spectroscopic and molecular modeling studies on paramagnetic lanthanide(III)-quercetin complexes
Authors: Ansari Anees A.
Published: August 2008

Nine coordinated [Ln(quercetin)3]nH2O complexes were synthesized in non-aqueous solution (where, n = 0 for Pr, Sm, Gd, Tb, Dy and Ho; n = 3, for La and Nd). The complexes were characterized by elemental analysis, molar conductance, UV – vis spectra, IR spectra, thermal analysis and NMR spectra. The optimized structures of the complexes were obtained by molecular modeling. The complexes behave as non-electrolytes in DMSO. TGA study showed anhydrous nature of the complexes (except La and Nd). The 1H NMR spectra of lanthanum, praseodymium, neodymium and samarium complexes have been studied in DMSO-d6. The complexes do not dissociate in DMSO and retain their coordination number. The NMR spectra of paramagnetic and diamagnetic complexes of quercetin exhibit lower as well as higher field shifts that show change in geometry during the metal ligand coordination.
cneViewer: a database of conserved non-coding elements for studies of tissue-specific gene regulation
Authors: Persampieri Jason , Ritter Deborah I. , Lees Daniel , Lehoczky Jessica , Li Qiang , Guo Su , Chuang Jeffrey H.
Published: August 2008

Summary: There are thousands of strongly conserved non-coding elements (CNEs) in vertebrate genomes, and their functions remain largely unknown. However, without biologically relevant criteria for prioritizing them, selecting a particular CNE sequences to study can be haphazard. To address this problem, we present cneViewer—a database and webtool that systematizes information on conserved non-coding DNA elements in zebrafish. A key feature here is the ability to search for CNEs that may be relevant to tissue-specific gene regulation, based on known developmental expression patterns of nearby genes. cneViewer provides this and other organizing features that significantly facilitate experimental design and CNE analysis.

Availability:  http://cneviewer.zebrafishcne.org

Contact:  chuangj@bc.edu
Arthur James Cain. 25 July 1921 — 20 August 1999
Authors: Clarke Bryan C.
Published: August 2008

Arthur Cain was a polymath, and one of Britain's leading evolutionary biologists. A strong believer in, and advocate for, the importance of natural selection, he greatly influenced evolutionary thought during the period from the 1950s to the 1980s. He wrote important papers in many areas of biology, and he was a noted historian of science.
1-[2-Oxo-1′-phenyl-2′,3′,5′,6′,7′,7a'-hexahydroindoline-3-spiro-3′-1′H-pyrrolizin-2′-yl]-3-phenylprop-2-en-1-one
Authors: Nirmala S. , Murugan R. , Kamala E. Theboral Sugi , Sudha L. , Sriman Narayanan S.
Published: August 2008

In the title compound, C29H26N2O2, one of the pyrrolidine rings in the pyrrolizine system is disordered, with site occupancies ofca0.55 and 0.45. Both components of the disordered pyrrolidine ring adopt envelope conformations, whereas the other pyrrolidine ring adopts a twist conformation. The molecules are linked into centrosymmetric dimers by N—H...O hydrogen bonds and the dimers are connectedviaC—H...π interactions.
Inflammatory markers and visceral fat are inversely associated with maximal oxygen consumption in women with polycystic ovary syndrome (PCOS)
Authors: Giallauria Francesco , Palomba Stefano , De Sio Ilario , Maresca Luigi , Vuolo Laura , Savastano Silvia , Lombardi Gaetano , Colao Annamaria , Vigorito Carlo , Orio Francesco
Published: August 2008

Background  We investigated whether several different inflammatory markers including C‐reactive protein (CRP) and fibrinogen and white blood cells (WBCs) count, are associated with maximal oxygen consumption (VO2max) in women with polycystic ovary syndrome (PCOS).

Methods  In PCOS women (n = 124, 24·1 ± 4·5 year‐old) VO2max was measured during symptom‐limited cardiopulmonary exercise test. Abdominal fat distribution was determined by ultrasound. Physical activity level was assessed by a standardized questionnaire. CRP was measured by immunoassays, fibrinogen by the Clauss method, and WBCs count with a Coulter counter.

Results  Pearson's analysis showed a significant correlation between VO2max and logCRP (r = –0·437, P < 0·001), fibrinogen (r = –0·479, P < 0·001), and WBCs count (r = –0·438, P < 0·001). Multivariable logistic regression model showed that age (β = –0·127, P = 0·005), AUCINS (β = –0·335, P < 0·001), HDL‐C (β = 0·390, P < 0·001), physical activity score (β = 0·238, P = 0·002), visceral fat (β =–0·184), P = 0·023), FAI (β = –0·291, P = 0·028); CRP (β = –0·216, P = 0·011), fibrinogen (β = –0·113, P = 0·008) and WBCs count (β = –0·177, P < 0·001) were significantly associated with VO2max.

Conclusions  Acute‐phase reactants, such as CRP and fibrinogen, and WBCs count were independently and inversely associated with a direct measure of cardiorespiratory fitness (VO2max) in women with PCOS, even after adjustment for physical activity level and other potential confounding factors. These findings add to the growing body of evidence linking inflammation to cardiorespiratory fitness in PCOS women.
Benzofuran derivatives and the thyroid
Authors: Han T. S. , Williams G. R. , Vanderpump M. P. J.
Published: August 2008

Amiodarone and dronedarone are two clinically important benzofuran derivatives. Amiodarone has been used widely for treating resistant tachyarrhythmias in the past three decades. However amiodarone and its main metabolically active metabolite desethylamiodarone can adversely affect many organs, including the thyroid gland. Amiodarone‐induced thyroid disorders are common and often present as a management challenge for endocrinologists. The pathogenesis of amiodarone‐induced thyroid dysfunction is complex but the inherent effects of the drug itself as well as its high iodine content appear to play a central role. The non‐iodinated dronedarone also exhibits anti‐arrhythmic properties but appears to be less toxic to the thyroid. This review describes the biochemistry of benzofuran derivatives, including their pharmacology and the physiology necessary for understanding the cellular mechanisms involved in their actions. The known effects of these compounds on thyroid action are described. Recommendations for management of amiodarone‐induced hypothyroidism and thyrotoxicosis are suggested. Dronedarone appears to be an alternative but less‐effective anti‐arrhythmic agent and it does not have adverse effects on thyroid function. It may have a future role as an alternative agent in patients being considered for amiodarone therapy especially those at high risk of developing thyroid dysfunction but not in severe heart failure.
The importance of transport hubs in stepping‐stone invasions
Authors: Floerl O. , Inglis G. J. , Dey K. , Smith A.
Published: August 2008

Biological invasions are characterized by occasional long‐distance, human‐assisted dispersal. Centres of human transportation that are connected by trade to a wide range of other locations (‘transport hubs’) may be important catalysts of the rate at which new populations of an invader are established.

We developed a spatially explicit stochastic model to simulate the spread of a hypothetical marine invader by hull fouling. The model was based on classic ‘Susceptible–Infected–Resistant’ models used in medical epidemiology. It was parameterized using empirical data on the colonization of vessel hulls by fouling organisms, and on maintenance and travel patterns of ~1300 domestic and international yachts around New Zealand. Thirty‐six marinas were grouped into three categories that represented a gradient in the number of other transport nodes each marina was ‘connected’ to and the frequencies of yacht movements between them. Invasions were seeded in three locations from each category. Simulations were run over 10 years to determine differences in the trajectory of invasions originating from busy and less frequented transport nodes.

Busy ‘hub’ locations were 75% more likely to become infected by an invader than quieter locations. Infection of hub nodes occurred at an earlier average stage in the invasion sequence. This occurred irrespective of whether the initial source of the invasion was associated with low or high traffic volume and connectivity.

Biotic invasions originating from hub locations did not consistently result in faster spread, or a larger number of secondary infestations. However, the rate of spread from hubs was less variable than from quieter nodes and was less often preceded by a prolonged lag period.

Synthesis and applications. Rapid spread of invasive organisms can occur from busy and from seemingly unimportant transport nodes. Busy locations were consistently more likely to become infested by an invader and to accelerate spread to secondary locations faster. Busy transport hubs should be considered a priority for the allocation of preventative and management efforts, such as regular baseline or target surveys and the development of incursion response plans that minimize the risk of spread within the transport network.
Development of a Sensitive Serological Method for Specific Detection of Latent Infection of Macrophomina phaseolina in Cowpea
Authors: Afouda Leonard , Wolf Gerhard , Wydra Kerstin
Published: August 2008

A double‐antibody sandwich enzyme‐linked immunosorbent assay (DAS‐ELISA) was developed for the specific detection and quantification of Macrophomina phaseolina in plant tissue. Both polyclonal antisera produced against immunogens from mycelium and culture filtrate of M. phaseolina detected the fungus in mycelial and plant extracts, although the antibodies raised against mycelium were more sensitive. No cross‐reaction occurred with Rhizopus stolonifer, Pythium ultimum, Mucor hiemalis, Fusarium oxysporum, Septoria nodorum, Rhizoctonia solani, Sclerotinia sclerotiorum, Phytophthora infestans and Aspergillus niger. In enzyme assays, activity of the endo‐acting hydrolytic enzymes 1,3‐β‐glucanase and, less, cellulase, but not xylanase was detected in infected plants. DAS‐ELISA was more sensitive than the 1,3‐β‐glucanase assay. In polyacrylamide gel electrophoresis (PAGE) up to 18 protein bands were observed, with four bands occurring in the 12 tested isolates deriving from various geographical origin in Niger and Nigeria. The enzyme assays and protein patterns were considered not suitable for specific M. phaseolina detection. Macrophomina phaseolina was essentially located in the roots and hypocotyls, and less in epicotyls and leaves of infected plants. The antibodies were also useful to detect latent infection and the infection of cowpea seeds.
ADENOVIRUS‐MEDIATED FKBP12.6 OVEREXPRESSION INDUCES HYPERTROPHY AND APOPTOSIS IN CULTURED NEONATAL CARDIOMYOCYTES
Authors: Zhong Jian , Chen Jing , Cao Tingbin , Wang Lijuan , Zhang Weiguo , Liu Daoyan , Zhu Zhiming
Published: August 2008

Cardiac ryanodine RyR2 receptors regulate Ca2+ release from the sarcoplasmic reticulum (SR). FK506 binding protein (FKBP) 12.6 prevents aberrant SR Ca2+ leakage during diastole, thereby maintaining the integrity of RyR2 function. Previous studies have focused mainly on FKBP12.6 deficiency and so the pathophysiological consequences of FKBP12.6 overexpression remain unclear. Herein, we investigate the effect of FKBP12.6 overexpression on cardiac hypertrophic and apoptotic signalling.

Human FKBP12.6 cDNA was cloned into pAdTrack‐CMV and the resulting plasmid, along with a control empty plasmid, were transfected into bacteria. The resulting virus, namely Ad‐FKBP12.6 containing green fluorescent protein, was propagated and purified. Neonatal rat cardiomyocytes were infected with this virus. Protein and DNA synthesis were measured by [3H]‐leucine and [3H]‐thymidine incorporation, respectively. Expression of p38 mitogen‐activated protein kinase (MAPK), phosphorylated extracellular signal‐regulated kinase 1 or 2 (p‐ERK1/2) and Bax were examined by western blotting.

Compared with control cells, cardiomyocytes that overexpressed FKBP12.6 became hypertrophic and hyperplastic, with increased levels of both p38 MAPK and p‐ERK1/2. At the same time, overexpression of FKBP12.6 induced apoptosis of cardiomyocytes, as determined by both Bax protein expression and DNA fragmentation. Rapamycin treatment downregulated the expression of p‐ERK1/2, p38 MAPK and Bax in stimulated cardiomyocytes, with or without FKBP12.6 overexpression, and enhanced protein synthesis, but had no effect on DNA synthesis in cardiomyocytes.

In conclusion, FKBP12.6 overexpression may participate in pathophysiological processes through both hypertrophic and apoptotic signalling pathways, leading to cardiomyocyte damage and death.
Adjustable continence therapy (ProACT) and bone anchored male sling: Comparison of two new treatments of post prostatectomy incontinence
Authors: Crivellaro Simone , Singla Ajay , Aggarwal Neelesh , Frea Bruno , Kocjancic Ervin
Published: August 2008

Objectives:  To compare the efficacy of two surgical treatments for male urinary stress incontinence: adjustable continence therapy (ProACT) and bone anchored male sling (BAMS).

Methods:  Eighty‐four consecutive post radical prostatectomy incontinent patients received ProACT (n = 46) or BAMS (n = 38) implantation by two different operators in two different centres. Eighty of them had a complete follow up. Both groups were prospectively assessed by number of pads per day and a validated questionnaire (UCLA/RAND). Complications rate and mean operating times were compared. All comparisons were analyzed using the t test, Fischer's exact test and χ2 analysis (significance P < 0.05).

Results:  At a mean follow up of 19 and 33 months respectively, 30/44 (68%) patients treated with ProACT were dry (0/1 safety pad) in comparison with 23/36 (64%) patients treated with BAMS (P > 0.05). Stratifying the results, ProACT had 33/39 (85%) dry patients in severe (more than three pads/day) preoperative incontinence, in comparison with 21/26 (81%) for BAMS (P > 0.05). The UCLA/RAND questionnaire showed an average increase of 11.7 points (from 10.2 to 21.9) for ProACT and of 10 points (from 11.9 to 21.9) for BAMS (P > 0.05). Complications included removal of ProACT and BAMS in 6/44 (14%) and 2/36 (6%), respectively. Mean operating time was 18 min and 45 min (P < 0.05) for ProACT and BAMS, respectively.

Conclusions:  ProACT and BAMS are both associated with a satisfactory rate of success. ProACT results seem to be better for severe incontinence and BAMS for mild incontinence. The operation time of ProACT is shorter.
Outcomes of patients after aborted radical cystectomy for intraoperative findings of metastatic disease
Authors: Guzzo Thomas J. , Rogers Craig G. , Deng Chris Y. , Bivalacqua Trinity J. , Palapattu Ganesh S. , Bastian Patrick J. , Eisenberger Mario A. , Schoenberg Mark P. , Gonzalgo Mark L.
Published: August 2008

OBJECTIVES

To assess the clinical outcome of patients with bladder cancer who underwent attempted radical cystectomy (RC) with curative intent, but whose procedures were aborted due to intraoperative findings of metastatic disease, as the presence of metastatic disease at RC is associated with a poor prognosis and there are no data on the optimum management strategy in this situation.

PATIENTS AND METHODS

In all, 248 consecutive patients with bladder cancer had attempted RC at one academic institution between 1994 and 2003. We retrospectively reviewed the records of 35 patients who had an aborted RC due to intraoperative findings of metastatic disease. The pathological characteristics, time to recurrence, overall survival, disease‐specific survival, and suitability for adjuvant or salvage therapies were examined.

RESULTS

Of the 35 patients who had an aborted RC for metastatic disease, 21 (60%) died from the disease within the study period (median time to cancer‐specific death 26.4 months), 11 (31%) are alive with evidence of persistent disease or progression, and three (9%) are alive with no evidence of recurrence or progression. Seven patients had a salvage RC after successful adjuvant treatment, of whom three died from recurrent disease (at a mean of 46.5 months after initial exploration, 31.9 months after salvage RC), one is alive with bladder cancer recurrence to the rectum 10 months after salvage cystectomy, and three have no evidence of disease progression at a mean of 10 months after salvage RC.

CONCLUSIONS

The prognosis of patients who undergo an aborted attempt at curative RC due to intraoperative findings of metastatic disease is poor. Although a few patients might subsequently have salvage RC, many of these patients still have poor outcomes even if adjuvant treatments are used. When metastatic disease is discovered at RC, completing the cystectomy should be considered, although further studies are needed to show a clinical benefit.
Four weeks of near‐normalization of blood glucose has no effect on postprandial GLP‐1 and GIP secretion, but augments pancreatic B‐cell responsiveness to a meal in patients with Type 2 diabetes
Authors: Højberg P. V. , Vilsbøll T. , Zander M. , Knop F. K. , Krarup T. , Vølund A. , Holst J. J. , Madsbad S.
Published: August 2008

Objective   The aim of the present study was to investigate whether 4 weeks of near‐normalization of blood glucose (BG) improves incretin hormone secretion and pancreatic B‐cell function during a mixed meal.

Research design and methods   Nine patients with Type 2 diabetes in poor glycaemic control [glycated haemoglobin (HbA1c) 8.0 ± 0.4%] were investigated before and after 4 weeks of near‐normalization of BG (mean BG 6.4 ± 0.3 mmol/l) using insulin treatment. HbA1c after insulin treatment was 6.6 ± 0.3%. For comparison, nine healthy control subjects were also studied. Postprandial glucagon‐like peptide 1 (GLP‐1) and glucose‐dependent insulinotropic polypeptide (GIP) incremental responses were assessed during a mixed meal test. Fasting and postprandial pancreatic B‐cell function was determined from calculations of insulin secretion rates in relation to plasma glucose.

Results   There was no difference in IAUCtotalGLP‐1 or in IAUCtotalGIP between the two experimental days. B‐cell sensitivity to glucose (insulinogenic index) did not differ before and after insulin treatment in the fasting state (0.21 ± 0.17 vs. 0.25 ± 0.10 pmol kg−1 min−1/mmol l−1), but improved significantly during the first 30 min after start of the meal (0.28 ± 0.07 vs. 0.46 ± 0.06 pmol kg−1 min−1/mmol l−1) and during the following 4 h (0.34 ± 0.09 vs. 0.56 ± 0.07 pmol kg−1 min−1/ mmol l−1). The B‐cell responsiveness to changes in plasma glucose, expressed as the slope of the linear relationship between the insulin secretion rate and the concomitant plasma glucose increased from 0.59 ± 0.16 to 0.94 ± 0.13 pmol kg−1 min−1/ mmol l−1 (P < 0.07).

Conclusions   Four weeks of near‐normalization of BG had no effect on postprandial secretion of incretin hormones. Nevertheless, several parameters of meal‐induced insulin secretion improved after insulin treatment.
Cultural barriers in the education of cardiovascular disease patients in Iran
Authors: Farahani M.A. , Mohammadi E. , Ahmadi F. , Maleki M. , Hajizadeh E.
Published: August 2008

Background:  Cardiovascular diseases are responsible for the highest mortality rate in Iran; however, there is a lack of evidence for cultural factors influencing patient education. Such information is important for the provision of effective patient care.

Aim:  To identify key issues relating to cultural factors influencing education of cardiovascular disease patients in Iran.

Methods:  The qualitative research approach was used in this study, with open‐ended interviews used to gather data. Eighteen nurses, four cardiovascular specialists, nine patients with cardiovascular disease and four family members were interviewed at two educational hospitals in Tehran. Interviews were taped, transcribed and analysed using constant comparative analysis.

Findings:  Participants expressed a range of cultural factors influencing patient education. Five themes emerged from the analysis: (a) patients' lifestyle, (b) beliefs about disease and treatment, (c) concealment of true diagnosis, (d) different opinions regarding the preferred instructor, and (e) ineffective communication.

Conclusion:  Findings show that cultural beliefs may act as risk factors for, or serve to intensify, cardiovascular disease. Consideration of these factors is essential for the success of patient education programmes.
Language barriers and qualitative nursing research: methodological considerations
Authors: Squires A.
Published: August 2008

Aim:  This review of the literature synthesizes methodological recommendations for the use of translators and interpreters in cross‐language qualitative research.

Background:  Cross‐language qualitative research involves the use of interpreters and translators to mediate a language barrier between researchers and participants. Qualitative nurse researchers successfully address language barriers between themselves and their participants when they systematically plan for how they will use interpreters and translators throughout the research process. Experienced qualitative researchers recognize that translators can generate qualitative data through translation processes and by participating in data analysis. Failure to address language barriers and the methodological challenges they present threatens the credibility, transferability, dependability and confirmability of cross‐language qualitative nursing research. Through a synthesis of the cross‐language qualitative methods literature, this article reviews the basics of language competence, translator and interpreter qualifications, and roles for each kind of qualitative research approach. Methodological and ethical considerations are also provided.

Conclusion:  By systematically addressing the methodological challenges cross‐language research presents, nurse researchers can produce better evidence for nursing practice and policy making when working across different language groups. Findings from qualitative studies will also accurately represent the experiences of the participants without concern that the meaning was lost in translation.
Learning through teaching: Peer‐mediated instruction in minimally invasive education
Authors: Dangwal Ritu , Kapur Preeti
Published: August 2008

The current paper provides insight into the learning strategies adopted by children working at Minimally Invasive Education (MIE) Learning Stations. Previous research has clearly indicated the attainment of basic computer literacy by groups of young children in the age groups of 7–14 years. This learning takes place due to the emergence and development of group social processes, an aspect crucial for achieving basic computing skills. The paper describes the process of socially shared understanding and learning as being crucial to individual learning. It is to be noted that this approach of socially shared learning does not challenge the analysis of the individual level of processing; it maintains that individual learning is vital in any learning context, but insufficient to build the psychology of learning. MIE research is of the view that young children learn through interaction with others, particularly peers as it provides an important context for social and cognitive learning. For it is in this way that children make sense of their own experience and environment. Hence, schools are not the only privileged sites of learning.