bluuebunny/crossref_metadata_2025 huggingface dataset:
A vector of high‐temperature paleo‐fluid flow deduced from mass transfer across permeability barriers (quartz veins)
Authors: DIPPLE G.M. , BONS P. , OLIVER N.H.S.
Published: April 2005

Quartz veins acted as impermeable barriers to regional fluid flow and not as fluid‐flow conduits in Mesoproterozoic rocks of the Mt Painter Block, South Australia. Systematically distributed asymmetric alteration selvedges consisting of a muscovite‐rich zone paired with a biotite‐rich zone are centered on quartz veins in quartz–muscovite–biotite schist. Geometric analysis of the orientation and facing of 126 veins at Nooldoonooldoona Waterhole reveals a single direction along which a maximum of all veins have a muscovite‐rich side, irrespective of their specific individual orientation. This direction represents a Mesoproterozoic fluid‐flow vector and the veins represent permeability barriers to the flow. The pale muscovite‐rich zones formed on the downstream side of the vein and the dark biotite‐rich zones mark the upstream side. The alteration couplets formed from mica schist at constant Zr, Ga, Sc, and involved increases in Si, Na, Al and decreases in K, Fe, Mg for pale alteration zones, and inverse alteration within dark zones. The asymmetry of the alteration couplets is best explained by the pressure dependence of mineral–fluid equilibria. These equilibria, in combination with a Darcian flow model for coupled advection and diffusion, and with permeability barriers imposed by the quartz veins, simulate the pattern of both fluid flow and differential, asymmetric metasomatism. The determined vector of fluid flow lies along the regional foliation and is consistent with the known distribution of regional alteration products. The presence of asymmetric alteration zones in rock containing abundant pre‐alteration veins suggests that vein‐rich material may have generally retarded regional fluid flow.
Barite–pyrite mineralization of the Wiesbaden thermal spring system, Germany: a 500‐kyr record of geochemical evolution
Authors: WAGNER T. , KIRNBAUER T. , BOYCE A. J. , FALLICK A. E.
Published: April 2005

Barite–(pyrite) mineralizations from the thermal springs of Wiesbaden, Rhenish Massif, Germany, have been studied to place constraints on the geochemical evolution of the hydrothermal system in space and time. The thermal springs, characterized by high total dissolved solids (TDS) contents and predominance of NaCl, ascend from aquifers at 3–4 km depth and discharge at a temperature of 65–70°C. The barite–(pyrite) mineralization is found in upflow and discharge zones of the present‐day thermal springs as well as at elevations up to 50 m above the current water table. Hence, this mineralization style constitutes a continuous record of the hydrothermal activity, linking the past evolution with the present state of this geothermal system. The sulphur isotope signatures of the mineralization indicate a continuous decrease of the δ34S of sulphate from +16.9‰ in the oldest barite to +10.1‰ in the present‐day thermal water. The δ34S values of barite closely resemble various recently active thermal springs along the southern margin of the Rhenish Massif and contrast strongly with different regional ground and mineral waters. The mineralogical and isotopic signatures, combined with calculations based on uplift rates and the regional geological history, indicate a minimum activity of the thermal spring system at Wiesbaden of about 500 000 years. This timeframe is considerably larger than conservative models, which estimate the duration of thermal spring systems in continental intraplate settings to last for several 10 000 years. The calculated equilibrium sulphur isotope temperatures of coexisting barite and pyrite range between 65 and 80°C, close to the discharge temperature of the springs, which would indicate apparent equilibrium precipitation. Kinetic modelling of the re‐equilibration of the sulphate–sulphide pair during water ascent shows that this process would require 220 Myr. Therefore, we conclude that pyrite is formed from precursor Fe monosulphide phases, which rapidly precipitate in the near‐surface environment, preserving the isotope fractionation between dissolved sulphate and sulphide established in the deep aquifer. Equilibrium modelling of water–mineral reactions shows slight supersaturation of barite at the discharge temperature. Pyrite is already strongly supersaturated at the temperatures estimated for the aquifer (110°C) and processes in the near‐surface environment are most probably related to contact of the thermal water with atmospheric oxygen, resulting in formation of oxidized intermediate sulphur species and precipitation of Fe monosulphide phases, which subsequently recrystallize to pyrite.
Isolation and characterization of Lactobacillus strains involved in koumiss fermentation
Authors: DANOVA SVETLA , PETROV KALOYAN , PAVLOV PLAMEN , PETROVA PENKA
Published: April 2005

Koumiss is a slightly alcoholic fermented milk beverage, originally obtained by using natural mix starters (lactic acid bacteria and yeast). Seven Lactobacillus strains from lyophilized koumiss were isolated and identified as L. salivarius, L. buchneri and L. plantarum. The process of lactic acid fermentation caused by koumiss strains was faster (9–13 h) than that with other lactobacilli. The conversion ratio of glucose to lactic acid ranged from 47% to 79% and was strain dependent. All strains were resistant to low pH. Three of the strains isolated were viable during prolonged cold storage in fermented milk (3 weeks at 4°C).
Inhibition of neuronal apoptosis by the cyclin‐dependent kinase inhibitor GW8510: Identification of 3′ substituted indolones as a scaffold for the development of neuroprotective drugs
Authors: Johnson Kyle , Liu Li , Majd Nazanin K , Chavez Cindy , Chin Paul C. , Morrison Brad , Wang Lulu , Park Jane , Chugh Priti , Chen Hsin‐Mei , D'Mello Santosh R.
Published: April 2005

Increasing evidence suggests that neuronal apoptosis is triggered by the inappropriate activation of cyclin‐dependent kinases leading to an abortive re‐entry of neurons into the cell cycle. Pharmacological inhibitors of cell‐cycle progression may therefore have value in the treatment of neurodegenerative diseases in humans. GW8510 is a 3′ substituted indolone that was developed recently as an inhibitor of cyclin‐dependent kinase 2 (CDK2). We found that GW8510 inhibits the death of cerebellar granule neurons caused by switching them from high potassium (HK) medium to low potassium (LK) medium. Although GW8510 inhibits CDK2 and other CDKs when tested in in vitro biochemical assays, when used on cultured neurons it only inhibits CDK5, a cytoplasmic CDK that is not associated with cell‐cycle progression. Treatment of cultured HEK293T cells with GW8510 does not inhibit cell‐cycle progression, consistent with its inability to inhibit mitotic CDKs in intact cells. Neuroprotection by GW8510 is independent of Akt and MEK‐ERK signaling. Furthermore, GW8510 does not block the LK‐induced activation of Gsk3βand, while inhibiting c‐jun phosphorylation, does not inhibit the increase in c‐jun expression observed in apoptotic neurons. We also examined the effectiveness of other 3′ substituted indolone compounds to protect against neuronal apoptosis. We found that like GW8510, the VEGF Receptor 2 Kinase Inhibitors [3‐(1H‐pyrrol‐2‐ylmethylene)‐1,3‐dihydroindol‐2‐one], {(Z)‐3‐[2,4‐Dimethyl‐3‐(ethoxycarbonyl)pyrrol‐5‐yl)methylidenyl]indol‐2‐one} and [(Z)‐5‐Bromo‐3‐(4,5,6,6‐tetrahydro‐1H‐indol‐2‐ylmethylene)‐1,3‐dihydroindol‐2‐one], the Src family kinase inhibitor SU6656 and a commercially available inactive structural analog of an RNA‐dependent protein kinase inhibitor 5‐Chloro‐3‐(3,5‐dichloro‐4‐hydroxybenzylidene)‐1,3‐dihydro‐indol‐2‐one, are all neuroprotective when tested on LK‐treated neurons. Along with our recent identification of the c‐Raf inhibitor GW5074 (also a 3′ substituted indolone) as a neuroprotective compound, our findings identify the 3′ substituted indolone as a core structure for the designing of neuroprotective drugs that may be used to treat neurodegenerative diseases in humans.
Ca2+‐induced permeabilization promotes free radical release from rat brain mitochondria with partially inhibited complex I
Authors: Votyakova Tatyana V. , Reynolds Ian J.
Published: April 2005

Mitochondrial complex I dysfunction has been implicated in a number of brain pathologies, putatively owing to an increased rate of reactive oxygen species (ROS) release. However, the mechanisms regulating the ROS burden are poorly understood. In this study we investigated the effect of Ca2+ loads on ROS release from rat brain mitochondria with complex I partially inhibited by rotenone. The addition of 20 nm rotenone to brain mitochondria increased ROS release. Ca2+ (100 µm) alone had no effect on ROS release, but greatly potentiated the effects of rotenone. The effect of Ca2+ was decreased by ruthenium red. Ca2+‐challenged mitochondria lose about 88% of their glutathione and 46% of their cytochrome c under these conditions, although this depends only on Ca2+ loading and not complex I inhibition. ADP in combination with oligomycin decreased the loss of glutathione and cytochrome c and free radical generation. Cyclosporin A alone was ineffective in preventing these effects, but augmented the protection provided by ADP and oligomycin. Non‐specific permeabilization of mitochondria with alamethicin also increased the ROS signal, but only when combined with partial inhibition of complex I. These results demonstrate that Ca2+ can greatly increase ROS release by brain mitochondria when complex I is impaired.
Serotonin via 5‐HT7 receptors activates p38 mitogen‐activated protein kinase and protein kinase C ɛ resulting in interleukin‐6 synthesis in human U373 MG astrocytoma cells
Authors: Lieb Klaus , Biersack Lisa , Waschbisch Anne , Orlikowski Sonja , Akundi Ravi Shankar , Candelario‐Jalil Eduardo , Hüll Michael , Fiebich Bernd L.
Published: April 2005

Serotonin [5‐hydroxytryptamine (5‐HT)] is a widely distributed neurotransmitter which is involved in neuroimmunomodulatory processes. Previously, it has been demonstrated that 5‐HT may induce interleukin (IL)‐6 expression in primary rat hippocampal astrocytes. The present study was undertaken to investigate the molecular pathways underlying this induction of IL‐6 synthesis. As a model system, we used the human astrocytoma cell line U373 MG, which synthesizes IL‐6 upon stimulation with various inducers. 5‐HT dose‐ and time‐dependently induced IL‐6 protein synthesis. We identified several 5‐HT receptors to be expressed on U373 MG cells, including the 5‐HT1D, 5‐HT2A, 5‐HT3 and 5‐HT7 receptors. In this report, we show that the 5‐HT‐induced IL‐6 release is mediated by the 5‐HT7 receptor based on several agonist/antagonists that were used. 5‐HT‐induced IL‐6 synthesis is inhibited by the partially selective 5‐HT7 receptor antagonist, pimozide, and the selective antagonist SB269970. Furthermore, IL‐6 synthesis was induced by the 5‐HT7 receptor agonist carboxamidotryptamin. In addition, we found p38 MAPKs and protein kinase C (PKC) ɛ to be involved in 5‐HT‐induced IL‐6 synthesis as specific inhibitors of these enzymes (SB202190 and RO‐31‐8425, respectively) blocked 5‐HT‐induced IL‐6 synthesis. Furthermore, 5‐HT mediated the phosphorylation of both p38 MAPK as well as the PKC ɛ isoform. The p42/44 MAPKs, however, were not involved in 5‐HT‐induced IL‐6 synthesis. This study shows, for the first time, a central role of 5‐HT7 receptor linked to p38 MAPK and PKC ɛ for the induction of cytokine synthesis in astrocytic cells.
Experimental gingivitis in cigarette smokers
Authors: Salvi Giovanni E. , Ramseier Christoph A. , Kandylaki M. , Sigrist L. , Awedowa E. , Lang Niklaus P.
Published: April 2005

Objective: To assess clinical and microbiological changes during experimental gingivitis in cigarette smokers and non‐smokers.

Material and Methods: Eleven current smokers (5 years) and 11 (never‐) non‐smokers periodontally healthy or with gingivitis (PPD4 mm) were included. According to the original model (Löe et al. 1965), an experimental 3‐week plaque accumulation period resulting in experimental gingivitis and a subsequent 2‐week period of optimal plaque control were performed. Subgingival plaque samples were collected at Days 0, 21 and 35 from one site per quadrant, pooled and analysed using checkerboard DNA–DNA hybridization.

Results: Smokers {mean age: 24.7±2.2 [standard deviation (SD)] years, range 21–28 years} had a mean lifetime cigarette exposure of 6.4±2.8 (SD) pack‐years, while non‐smokers presented with a mean age of 23.1±2.2 (SD) years (range 21–29 years). Between Days 0, 21 and 35, no statistically significant differences in mean Plaque and mean Gingival Index scores were observed between smokers and non‐smokers. In both smokers and non‐smokers, mean total DNA probe counts did not significantly differ nor increase between Days 0 and 21. Also, between Days 21 and 35 they did not significantly differ nor decrease. This was also true for the various proportions of bacterial complexes.

Conclusion: Both current smokers and (never‐) non‐smokers reacted to experimental plaque accumulation with gingival inflammation. Periodontal and microbiological parameters assessed in current cigarette smokers did not significantly differ from those in non‐smokers during an identical period of experimental plaque accumulation. Hence, the early host response to the bacterial challenge appears to be of similar magnitude and timing in both groups.
Bone regeneration at implants with turned or rough surfaces in self‐contained defects. An experimental study in the dog
Authors: Botticelli Daniele , Berglundh Tord , Persson Leif G. , Lindhe Jan
Published: April 2005

Background: Marginal hard tissue defects present at implants with a rough surface can heal with a high degree of bone fill and osseointegration. The healing of similar defects adjacent to implants with a smooth surface appears to be less predictable.

Objective: The aim was to compare bone healing at implants with turned or rough surface topographies placed in self‐contained defects using either a submerged or non‐submerged installation technique.

Material and Methods: Six dogs were used. Three months after tooth extraction four experimental sites were prepared for implant installation in both sides of the mandible. The marginal 5 mm of the canal prepared for the implant was widened. Thus, following implant placement a circumferential gap occurred between the bone tissue and the implant surface that was between 1 and 1.25 mm wide. In each side of the mandible two implants with a turned surface and two implants with a rough surface were installed. The implants in the right side were fully submerged, while a non‐submerged technique was applied in the left side. The animals were sacrificed 4 months later, block biopsies of each implant site were dissected and ground as well as paraffin sections were prepared.

Results: The marginal defects around rough surface implants exhibited after 4 months of healing substantial bone fill and a high degree of osseointegration following either the submerged or the non‐submerged installation technique. Healing at turned implants was characterized by incomplete bone fill and the presence of a connective tissue zone between the implant and the newly formed bone. The distance between the implant margin (M) and the most coronal level of bone‐to‐implant contact (B) at implants with a rough surface was 0.84±0.37 mm at submerged and 0.90±0.39 mm at non‐submerged sites. The distance M–B at implants with a turned surface was 3.39±0.52 mm at submerged and 3.23±0.68 mm at non‐submerged sites. The differences between the rough and turned implants regarding the length of distance M–B were statistically significant (paired t‐test).

Conclusion: Osseointegration at implants placed in sites with marginal defects is influenced by the surface characteristics of the implant.
The effect of a polyhexamethylene biguanide mouthrinse compared with a triclosan rinse and a chlorhexidine rinse on bacterial counts and 4‐day plaque re‐growth
Authors: Welk A. , Splieth C.H. , Schmidt‐Martens G. , Schwahn Ch. , Kocher Th. , Kramer A. , Rosin M.
Published: April 2005

Objectives: For various clinical applications, polyhexamethylene biguanide hydrochloride (PHMB) has been used for many years as an antiseptic in medicine. Recently, a 0.04% and a 0.12% PHMB mouthwash were shown to inhibit plaque re‐growth and to reduce oral bacterial counts. In this study, a 0.2% PHMB mouthrinse (A) was compared with a positive control 0.12% aqueous chlorhexidine solution (B), a commercially available 0.3% triclosan/2.0% polyvinyl methyl ether maleic acid copolymer mouthrinse (Colgate Total Plax®) (C), and a negative control placebo rinse (10% ethanol, flavour) (D).

Materials and Methods: The controlled clinical study was a double blind, randomized, four replicate cross ‐ over design. Plaque re‐growth was assessed with the Turesky et al. (1970) modification of the Quigley & Hein (1962) plaque index. The antibacterial effect was assessed by taking bacterial counts on the tooth surface (smears from the buccal surface of 16/26) and mucosa (smears from the buccal mucosa in opposite of area 16/26) after the professional prophylaxis and after the first rinse with the preparations on day 1 and prior to the clinical examination on day 5. Sixteen volunteers participated and, on day 1 of each study period were rendered plaque‐free, ceased toothcleaning, and rinsed twice daily with the allocated mouthrinse. On day 5, plaque was scored and smears were collected according to the protocol. A 10‐day wash‐out period was carried out between each rinse evaluation. Data were analysed using ancova with Bonferroni HSD adjustment for multiple comparisons (colony forming units per sample) with a significance level α=0.05.

Results: The 0.2% PHMB mouthrinse (A) was significantly better at inhibiting plaque than the placebo (D), but significant less effective than the 0.12% aqueous chlorhexidine solution (B). There is no significant difference between A and the 0.3% triclosan/2.0% copolymer mouthrinse (C).

Bacterial count reductions (tooth surface and mucosa) with PHMB (A) were significantly greater compared with the placebo (D) and triclosan (C), but significantly lower compared with chlorhexidine (B) (tooth surface) and equally effective compared with chlorhexidine (B) (mucosa).

Conclusion: Consistent with previous studies, a PHMB mouthrinse was shown to inhibit plaque re‐growth and to reduce oral bacterial counts, indicating that PHMB could be an alternative to established mouthrinses in preventive applications.
Root surface removal and resultant surface texture with diamond‐coated ultrasonic inserts: an in vitro and SEM study
Authors: Vastardis Sotirios , Yukna Raymond A. , Rice David A. , Mercante Don
Published: April 2005

Background: A new diamond‐coated ultrasonic insert has been developed for scaling and root planing, and it was evaluated in vitro for the amount of root surface removed and the roughness of the residual root surface as a result of instrumentation.

Methods: 48 extracted single‐rooted human teeth were ground flat on one root surface and mounted (flat side up) in PVC rings of standard height and diameter with improved dental stone. Each tooth surface was treated with either a plain ultrasonic insert (PI), an ultrasonic insert with a fine grit diamond coating (DI) or sharp Gracey curettes (HI). The mounted teeth were attached to a stepper motor which drove the teeth in a horizontal, reciprocal motion at a constant rate. The thickness from the flattened bottom of the ring to the flattened tooth surface was measured before and after 10, 20, and 30 instrumentation strokes for each root surface with each of the experimental instruments. A number of treated teeth were randomly selected for examination with SEM and a profilometer. Statistical analysis (analysis of co‐variance) was performed to compare the amounts of tooth structure removed among the 3 instruments and t‐test was used to compare the roughness of the treated root surfaces.

Results: The mean depth of root structure removed was PI 10.7 μm, HI 15.0 μm, and DI 46.2 μm after 10 strokes; and PI 21.6 μm, HI 33.2 and DI 142.0 μm after 30 strokes, respectively. On average, 0.9 μm, 1.3 μm, and 4.7 μm of root surface was removed with each stroke of PI, HI and DI, respectively. PI and HI were not different from each other for all the stroke cycles, while DI was significantly different from PI and HI for all the stroke cycles (p<0.0001). Analysis with the profilometer showed that the smoothest surface was produced by the PI followed by the HI. The DI produced a surface that was significantly rougher than the surface produced by the PI or HI.

Conclusion: These results suggest that diamond‐coated ultrasonic instruments will effectively plane roots, and that caution should be used during periodontal root planing procedures. Additionally, the diamond‐coated instruments will produce a rougher surface than the plain inserts or the hand curettes.
Polymorphisms of the interleukin‐18 gene in periodontitis patients
Authors: Folwaczny Matthias , Glas Jürgen , Török Helga‐Paula , Tonenchi Laurian , Paschos Ekaterini , Bauer Bernhard , Limbersky Olga , Folwaczny Christian
Published: April 2005

Background: Interleukin (IL)‐18 regulates the expression of the proinflammatory cytokine interferon (IFN)‐γ. The present study sought to test the putative involvement of six different IL‐18 gene polymorphisms in pre‐disposition to destructive periodontal disease.

Methods: A total of 123 patients with periodontitis and 121 healthy controls were genotyped for six IL‐18 polymorphisms at position −656, −607, −137, +113, +127 and codon 35/3. Genotyping has been performed by PCR and restriction fragment length polymorphism analysis. The frequencies of alleles and genotypes as well of haplotypes within both study groups were compared using the Pearson Chi‐square test at a level of significance of 5% (p<0.05).

Results: Coseggregation was found to be 100% for the two polymorphisms at position −656 and −607 as well as for the polymorphisms at position −137, +113, and +127. The distribution of genotypes for the IL‐18 gene polymorphism at position −656/−607 (p=0.854), at position −137/+113/+127 (p=0.320), and at codon 35/3 (p=0.481) was not significantly different among periodontitis patients if compared with healthy control subjects. The distribution of haplotype combinations for the −607 and −137 polymorphism also showed not significant difference between the both study groups (p=0.545).

Conclusion: Herein the six different IL‐18 gene polymorphisms were not associated with destructive periodontal disease.
CONDUCTING SENSORY RESEARCH WITH CHILDREN
Authors: POPPER RICHARD , KROLL JEFFREY J.
Published: April 2005

Sensory testing with children can provide important insight into their likes and dislikes. Sensory professionals need to use methods that are appropriate for different age groups. This article reviews the current state of knowledge in this area and stresses the importance of considering the sensory, cognitive and social factors that may impact how best to conduct testing with children.
Bachelier
Authors: Bernstein Jeremy
Published: April 2005

It is not generally known that the theory of Brownian motion developed by both Einstein and Smoluchowski had been anticipated by a French mathematician named Louis Bachelier in his doctoral thesis. Bachelier and his work are explored.
Projectiles, pendula, and special relativity
Authors: Price Richard H.
Published: April 2005

The kind of flat-earth gravity used in introductory physics appears in an accelerated reference system in special relativity. From this viewpoint, we work out the special relativistic description of a ballistic projectile and a simple pendulum, two examples of simple motion driven by earth-surface gravity. The analysis uses only the basic mathematical tools of special relativity typical of a first-year university course.
A direct comparison of conceptual learning and problem solving ability in traditional and studio style classrooms
Authors: Hoellwarth Chance , Moelter Matthew J. , Knight Randall D.
Published: April 2005

We present data on student performance on conceptual understanding and on quantitative problem-solving ability in introductory mechanics in both studio and traditional classroom modes. The conceptual measures used were the Force Concept Inventory and the Force and Motion Conceptual Evaluation. Quantitative problem-solving ability was measured with standard questions on the final exam. Our data compare three different quarters over the course of 2 years. In all three quarters, the normalized learning gain in conceptual understanding was significantly larger for students in the studio sections. At the same time, students in the studio sections performed the same or slightly worse on quantitative final exam problems.
A TWO-PARAMETER DEFORMED SUSY ALGEBRA FOR SUp/q(n)-COVARIANT (p,q)-DEFORMED FERMIONIC OSCILLATORS
Authors: ALGIN ABDULLAH , ARIK METIN
Published: April 2005

We construct a two-parameter deformed SUSY algebra by constructing SUSY generators which are bilinears of n (p,q)-deformed fermions covariant under the quantum group SU p/q(n) and n undeformed bosons. The Fock space representation of the algebra constructed is discussed and the total deformed Hamiltonian for such a system is obtained. Some physical applications of the quantum group covariant two-parameter deformed fermionic oscillator algebra are also considered.
GRAVITATIONAL FARADAY EFFECT INDUCED BY HIGH-POWER LASERS
Authors: JI PEIYONG , ZHOU HUA , LU H. Q.
Published: April 2005

Gravitational field produced by high-power laser is calculated according to the linearized Einstein field equation in weak field approximation. Gravitational Faraday effect of electromagnetic wave propagating in the above gravitational field is studied and the rotation angle of polarization plane of electromagnetic wave is derived. The result is discussed and estimated in the condition of present experimental facility.
A SURVEY OF XML APPLICATIONS ON SCIENCE AND TECHNOLOGY
Authors: LU ZHONGYU
Published: April 2005

Scientific data/documents play a significant role in academic research and industrial applications. In the era of information fusion, building knowledge and content management systems is necessary, particularly in multidisciplinary and interdisciplinary research. This paper discusses an overview about the impact of XML in knowledge and content management systems in science and technology; extends to the integration and implementation including the discussions of infrastructures, methodologies, some typical examples in case studies; finally, it ends with future research and development in a new challenge in information and knowledge engineering. It concluded that XML will make significant contributions to the next generation in information processing for scientific content management systems.
TRUST ENVIRONMENTS AND ENTREPRENEURIAL BEHAVIOR – EXPLORATORY EVIDENCE FROM ESTONIA, GERMANY AND RUSSIA
Authors: WELTER FRIEDERIKE , KAUTONEN TEEMU , CHEPURENKO ALEXANDER , MALIEVA ELENA , VENESAAR URVE
Published: April 2005

This paper explores the role of different trust environments in West and East Europe on the behavior of entrepreneurs. In a stable institutional environment (e.g., Germany, core regions in Russia) personal trust mainly plays a complementary role for entrepreneurial behavior, while in more fragile environments (e.g., peripheral regions in Russia) it can substitute for institutional deficiencies. The exploratory empirical data analyzed in this study comprise three countries (Estonia, Germany and Russia), and they stem from an international research project, which was supported by the Volkswagen Foundation. The empirical discussion focuses in particular on interfirm relations of small businesses as well as on the sources of assistance used by entrepreneurs in solving business problems. The preliminary results indicate that the forms of trust depend on the respective regional and sectoral environments, which draws attention to the difficulties of classifying whole countries as "high-trust" versus "low-trust". Limitations of the analysis refer to the cross-sectional nature of the survey data.
ROTATIONAL MATCHING PROBLEMS
Authors: CHIRIKJIAN GREGORY S. , KIM PETER T. , KOO JA-YONG , LEE CHRISTINE H.
Published: April 2005

This paper addresses the issue of obtaining the optimal rotation to match two functions on the sphere by minimizing the squared error norm and the Kullback–Leibler information criteria. In addition, the accuracy in terms of the band-limited approximations in both cases are also discussed. Algorithms for fast and accurate rotational matching play a significant role in many fields ranging from computational biology to spacecraft attitude estimation. In electron microscopy, peaks in the so-called "rotation function" determine correlations in orientation between density maps of macromolecular structures when the correspondence between the coordinates of the structures is not known. In X-ray crystallography, the rotational matching of Patterson functions in Fourier space is an important step in the determination of protein structures. In spacecraft attitude estimation, a star tracker compares observed patterns of stars with rotated versions of a template that is stored in its memory. Many algorithms for computing and sampling the rotation function have been proposed over the years. These methods usually expand the rotation function in a bandlimited Fourier series on the rotation group. In some contexts the highest peak of this function is interpreted as the optimal rotation of one structure into the other, and in other contexts multiple peaks describe symmetries in the functions being compared. Prior works on rotational matching seek to maximize the correlation between two functions on the sphere. We also consider the use of the Kullback–Leibler information criteria. A gradient descent algorithm is proposed for obtaining the optimal rotation, and a measure is defined to compare the convergence of this procedure applied to the maximal correlation and Kullback–Leibler information criteria.
Proteomic analysis on insulin signaling in human hematopoietic cells: identification of CLIC1 and SRp20 as novel downstream effectors of insulin
Authors: Saeki Kumiko , Yasugi Etsuko , Okuma Emiko , Breit Samuel N. , Nakamura Megumi , Toda Tosifusa , Kaburagi Yasushi , Yuo Akira
Published: April 2005

Insulin/IGF-I-dependent signals play important roles for the regulation of proliferation, differentiation, metabolism, and autophagy in various cells, including hematopoietic cells. Although the early protein kinase activation cascade has been intensively studied, the whole picture of intracellular signaling events has not yet been clarified. To identify novel downstream effectors of insulin-dependent signals in relatively early phases, we performed high-resolution two-dimensional electrophoresis (2-DE)-based proteomic analysis using human hematopoietic cells 1 h after insulin stimulation. We identified SRp20, a splicing factor, and CLIC1, an intracellular chloride ion channel, as novel downstream effectors besides previously reported effectors of Rho-guanine nucleotide dissociation inhibitor 2 and glutathione S-transferase-pi. Reduction in SRp20 was confirmed by one-dimensional Western blotting. Moreover, MG-132, a proteasome inhibitor, prevented this reduction. By contrast, upregulation of CLIC1 was not observed in one-dimensional Western blotting, unlike the 2-DE results. As hydrophilic proteins were predominantly recovered in 2-DE, the discrepancy between the 1-DE and 2-DE results may indicate a certain qualitative change of the protein. Indeed, the nuclear localization pattern of CLIC1 was remarkably changed by insulin stimulation. Thus insulin induces the proteasome-dependent degradation of SRp20 as well as the subnuclear relocalization of CLIC1.
Urodynamic properties and neurotransmitter dependence of urinary bladder contractility in the BK channel deletion model of overactive bladder
Authors: Thorneloe K. S. , Meredith A. L. , Knorn A. M. , Aldrich R. W. , Nelson M. T.
Published: April 2005

Overactive bladder and incontinence are major medical issues, which lack effective therapy. Previously, we showed (Meredith AL, Thornloe KS, Werner ME, Nelson MT, and Aldrich RW. J Biol Chem 279: 36746–36752, 2004) that the gene mSlo1 encodes large-conductance Ca2+-activated K+(BK) channels of urinary bladder smooth muscle (UBSM) and that ablation of mSlo1 leads to enhanced myogenic and nerve-mediated contractility and increased urination frequency. Here, we examine the in vivo urodynamic consequences and neurotransmitter dependence in the absence of the BK channel. The sensitivity of contractility to nerve stimulation was greatly enhanced in UBSM strips from Slo−/−mice. The stimulation frequency required to obtain a 50% maximal contraction was 8.3 ± 0.9 and 19.1 ± 1.8 Hz in Slo−/−and Slo+/+mice, respectively. This enhancement is at least partially due to alterations in UBSM excitability, as muscarinic-induced Slo−/−contractility is elevated in the absence of neuronal activity. Muscarinic-induced Slo−/−contractility was mimicked by blocking BK channels with iberiotoxin (IBTX) in Slo+/+strips, whereas IBTX had no effect on Slo−/−strips. IBTX also enhanced purinergic contractions of Slo+/+UBSM but was without effect on purinergic contractions of Slo−/−strips. In vivo bladder pressure and urine output measurements (cystometry) were performed on conscious, freely moving mice. Slo−/−mice exhibited increased bladder pressures, pronounced pressure oscillations, and urine dripping. Our results indicate that the BK channel in UBSM has a very significant role in urinary function and dysfunction and as such likely represents an important therapeutic target.
Increased propensity for apnea via dopamine-induced carotid body inhibition in sleeping dogs
Authors: Chenuel Bruno J. , Smith Curtis A. , Henderson Kathleen S. , Dempsey Jerome A.
Published: April 2005

We determined the effects of specific carotid body chemoreceptor inhibition on the propensity for apnea during sleep. We reduced the responsiveness of the carotid body chemoreceptors using intravenous dopamine infusions during non-rapid eye movement sleep in six dogs. Then we quantified the difference in end-tidal Pco2 (PetCO2) between eupnea and the apneic threshold, the “CO2 reserve,” by gradually reducing PetCO2 transiently with pressure support ventilation at progressively increased tidal volume until apnea occurred. Dopamine infusions decreased steady-state eupneic ventilation by 15 ± 6%, causing a mean CO2 retention of 3.9 ± 1.9 mmHg and a brief period of ventilatory instability. The apneic threshold PetCO2 rose 5.1 ± 1.9 Torr; thus the CO2 reserve was narrowed from −3.9 ± 0.62 Torr in control to −2.7 ± 0.78 Torr with dopamine. This decrease in the CO2 reserve with dopamine resulted solely from the 20.5 ± 11.3% increase in plant gain; the slope of the ventilatory response to CO2 below eupnea was unchanged from normal. We conclude that specific carotid chemoreceptor inhibition with dopamine increases the propensity for apnea during sleep by narrowing the CO2 reserve below eupnea. This narrowing is due solely to an increase in plant gain as the slope of the ventilatory response to CO2 below eupnea was unchanged from normal control. These findings have implications for the role of chemoreceptor inhibition/stimulation in the genesis of apnea and breathing periodicity during sleep.
The length dependence of muscle active force: considerations for parallel elastic properties
Authors: MacIntosh Brian R. , MacNaughton Meredith B.
Published: April 2005

The purpose of this study was to choose between two popular models of skeletal muscle: one with the parallel elastic component in parallel with both the contractile element and the series elastic component ( model A), and the other in which it is in parallel with only the contractile element ( model B). Passive and total forces were obtained at a variety of muscle lengths for the medial gastrocnemius muscle in anesthetized rats. Passive force was measured before the contraction ( passive A) or was estimated for the fascicle length at which peak total force occurred ( passive B). Fascicle length was measured with sonomicrometry. Active force was calculated by subtracting passive ( A or B) force from peak total force at each fascicle or muscle length. Optimal length, that fascicle length at which active force is maximized, was 13.1 ± 1.2 mm when passive A was subtracted and 14.0 ± 1.1 mm with passive B ( P < 0.01). Furthermore, the relationship between double-pulse contraction force and length was broader when calculated with passive B than with passive A. When the muscle was held at a long length, passive force decreased due to stress relaxation. This was accompanied by no change in fascicle length at the peak of the contraction and only a small corresponding decrease in peak total force. There is no explanation for the apparent increase in active force that would be obtained when subtracting passive A from the peak total force. Therefore, to calculate active force, it is appropriate to subtract passive force measured at the fascicle length corresponding to the length at which peak total force occurs, rather than passive force measured at the length at which the contraction begins.
Biomechanics of the lung parenchyma: critical roles of collagen and mechanical forces
Authors: Suki Béla , Ito Satoru , Stamenović Dimitrije , Lutchen Kenneth R. , Ingenito Edward P.
Published: April 2005

The biomechanical properties of connective tissues play fundamental roles in how mechanical interactions of the body with its environment produce physical forces at the cellular level. It is now recognized that mechanical interactions between cells and the extracellular matrix (ECM) have major regulatory effects on cellular physiology and cell-cycle kinetics that can lead to the reorganization and remodeling of the ECM. The connective tissues are composed of cells and the ECM, which includes water and a variety of biological macromolecules. The macromolecules that are most important in determining the mechanical properties of these tissues are collagen, elastin, and proteoglycans. Among these macromolecules, the most abundant and perhaps most critical for structural integrity is collagen. In this review, we examine how mechanical forces affect the physiological functioning of the lung parenchyma, with special emphasis on the role of collagen. First, we overview the composition of the connective tissue of the lung and their complex structural organization. We then describe how mechanical properties of the parenchyma arise from its composition as well as from the architectural organization of the connective tissue. We argue that, because collagen is the most important load-bearing component of the parenchymal connective tissue, it is also critical in determining the homeostasis and cellular responses to injury. Finally, we overview the interactions between the parenchymal collagen network and cellular remodeling and speculate how mechanotransduction might contribute to disease propagation and the development of small- and large-scale heterogeneities with implications to impaired lung function in emphysema.
G-CSF, but not corticosterone, mediates circulating neutrophilia induced by febrile-range hyperthermia
Authors: Ellis Garrettson S. , Carlson Drew E. , Hester Lisa , He Ju-Ren , Bagby Gregory J. , Singh Ishwar S. , Hasday Jeffery D.
Published: April 2005

We previously showed that sustained exposure to febrile-range hyperthermia (FRH) for 24 h caused an increase in circulating granulocyte colony-stimulating factor (G-CSF) levels and a peripheral neutrophilia in mice (Hasday J, Garrison A, Singh I, Standiford T, Ellis G, Rao S, He JR, Rice P, Frank M, Goldblum S, and Viscardi R. Am J Pathol 162: 2005–2017, 2003). In this study, we utilized a conscious temperature-clamped mouse model to analyze the kinetics of G-CSF expression and peripheral neutrophil expansion and the contributions of FRH-induced G-CSF expression, glucocorticoid generation, and catecholamine-induced neutrophil demargination. In conscious mice housed at an ambient temperature of 34.5°C, core temperature rapidly equilibrated at 39.5–40°C. Peripheral neutrophil counts increased 2-fold after 24-h exposure to hyperthermia, peaked at 3.6-fold baseline levels after 36-h exposure to FRH, and returned to baseline levels after 42 h of sustained hyperthermia. Plasma G-CSF levels were increased by 6.8-fold after 24 h and peaked at 40-fold baseline levels after 36 h in the hyperthermic mice. Plasma corticosterone levels peaked at 3.3-fold baseline levels after 30-h sustained hyperthermia and returned to baseline by 42 h. Immunoneutralization of G-CSF blocked FRH-induced peripheral neutrophilia, but blockade of the glucocorticoid receptor with mifepristone failed to modify FRH-induced neutrophilia. Epinephrine induced similar increases in peripheral blood absolute neutrophil counts in euthermic mice (2.2-fold increase) and mice exposed to FRH for 36 h (1.8-fold increase). Collectively, these data suggest that FRH-induced expression of G-CSF drives the sustained peripheral neutrophilia that occurs during sustained (36 h) hyperthermia, whereas glucocorticoid generation and catecholamine-induced demargination play little role in this response.
Monoaminergic Establishment of Rostrocaudal Gradients of Rhythmicity in the Neonatal Mouse Spinal Cord
Authors: Christie Kimberly J. , Whelan Patrick J.
Published: April 2005

Bath application of monoamines is a potent method for evoking locomotor activity in neonatal rats and mice. Monoamines also promote functional recovery in adult animals with spinal cord injuries by activating spinal cord networks. However, the mechanisms of their actions on spinal networks are largely unknown. In this study, we tested the hypothesis that monoamines establish rostrocaudal gradients of rhythmicity in the thoracolumbar spinal cord. Isolated neonatal mouse spinal cord preparations (P0–P2) were used. To assay excitability of networks by monoamines, we evoked a disinhibited rhythm by bath application of picrotoxin and strychnine and recorded neurograms from several thoracolumbar ventral roots. We first established that rostral and caudal segments of the thoracolumbar spinal cord had equal excitability by completely transecting preparations at the L3 segmental level and recording the frequency of the disinhibited rhythm from both segments. Next we established that a majority of ventral interneurons retrogradely labeled by calcium green dextran were active during network activity. We then bath applied combinations of monoaminergic agonists [5-HT and dopamine (DA)] known to elicit locomotor activity. Our results show that monoamines establish rostrocaudal gradients of rhythmicity in the thoracolumbar spinal cord. This may be one mechanism by which combinations of monoaminergic compounds normally stably activate locomotor networks.
Severe hypertension caused by alleles from normotensive Lewis for a quantitative trait locus on chromosome 2
Authors: Eliopoulos Vasiliki , Dutil Julie , Deng Yishu , Grondin Myrian , Deng Alan Y.
Published: April 2005

Pursuing fully a suggestion from linkage analysis that there might be a quantitative trait locus (QTL) for blood pressure (BP) in a chromosome (Chr) 2 region of the Dahl salt-sensitive rat (DSS), four congenic strains were made by replacing various fragments of DSS Chr 2 with those of Lewis (LEW). Consequently, a BP QTL was localized to a segment of around 3 cM or near 3 Mb on Chr 2 by comparative congenics. The BP-augmenting alleles of this QTL originated from the LEW rat, a normotensive strain compared with DSS. The dissection of a QTL with such a paradoxical effect illustrated the power of congenics in unearthing a gene hidden in the context of the whole animal system, presumably by interactions with other genes. The locus for the angiotensin II receptor AT-1B ( Agtr1b) is not supported as a candidate gene for the QTL because a congenic strain harboring it did not have an effect on BP. There are ∼19 known and unknown genes present in the QTL interval. Among them, no standout candidate genes are reputed to affect BP. Thus the QTL will likely represent a novel gene for BP regulation.
Macroarray analysis of coelomocyte gene expression in response to LPS in the sea urchin. Identification of unexpected immune diversity in an invertebrate
Authors: Nair Sham V. , Del Valle Heather , Gross Paul S. , Terwilliger David P. , Smith L. Courtney
Published: April 2005

The purple sea urchin, Strongylocentrotus purpuratus, is a member of the phylum Echinodermata, which is basal to the phylum Chordata within the deuterostome lineage of the animal kingdom. This relationship makes the analysis of the sea urchin immune system relevant to understanding the evolution of the deuterostome immune system leading to the Vertebrata. Subtractive suppression hybridization was employed to generate cDNA probes for screening high-density arrayed, conventional cDNA libraries to identify genes that were upregulated in coelomocytes responding to lipopolysaccharide. Results from 1,247 expressed sequence tags (ESTs) were used to infer that coelomocytes upregulated genes involved in RNA splicing, protein processing and targeting, secretion, endosomal activities, cell signaling, and alterations to the cytoskeletal architecture including interactions with the extracellular matrix. Of particular note was a set of transcripts represented by 60% of the ESTs analyzed, which encoded a previously uncharacterized family of closely related proteins, provisionally designated as 185/333. These transcripts exhibited a significant level of variation in their nucleotide sequence and evidence of putative alternative splicing that could yield up to 15 translatable elements. On the basis of the striking increase in gene expression in response to lipopolysaccharide and the unexpected level of diversity of the 185/333 messages, we propose that this set of transcripts encodes a family of putative immune response proteins that may represent a major component of an immunological response to bacterial challenge.
Characterization of a myeloma patient with a life-threatening hemorrhagic diathesis: presence of a lambda dimer protein inhibiting shear-induced platelet aggregation by binding to the A1 domain of vonWillebrand factor
Authors: Shinagawa Atsushi , Berndt Michael , Kaneko Shin , Suzukawa Kazumi , Hasegawa Yuichi , Shigeta Osamu , Nagasawa Toshiro , Kojima Hiroshi
Published: April 2005

We have identified a patient with IgD λ-type multiple myeloma who was characterized by a severe bleeding tendency, especially after puncture of arterial vessels. Both the bleeding time (>25 min) and activated partial thromboplastin time (APTT) were prolonged. To clarify the underlying pathogenesis, we purified the APTT-prolonging activity from the patient’s serum. The purified protein was a highly negatively-charged homodimer of the λ light chain. The λ dimer protein (M-protein) inhibited ristocetin-and high shear-induced platelet aggregation, dependent on platelet glycoprotein Ibα (GPIbα), but not epinephrine-, collagen-, ADP-, thrombin-, or botrocetin-induced platelet aggregation. The λ dimer protein inhibited the binding of platelets to immobilized or ristocetin-treated von Willebrand factor (VWF). Furthermore, a 39/34 kD fragment of VWF encompassing the A1 domain specifically bound to the immobilized λ dimer protein in the presence of ristocetin, suggesting that the λ dimer protein directly binds to the A1 domain of VWF. To help elucidate the binding site within the A1 domain, binding of ristocetin-treated VWF to the immobilized λ dimer protein was assayed in the presence of various anti-A1 domain monoclonal antibodies. Based on these data, we conclude that the λ dimer protein binds to the region of the A1 domain composed of helices α3 and α4 and thus interferes with VWF-GPIbα interaction. The existence of a protein that inhibits high shear-induced platelet aggregation in acquired von Willebrand disease (VWD) has only rarely been reported. The results suggest that the hemostatic function in arteries with high shear force is profoundly disrupted if the binding of GPIbα to VWF is abrogated, supporting the relevance of shear-induced VWF interaction with GPIbα in the initiation of the hemostatic process.