bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of obesity management in medical examination
Authors: Treyzon Leo
Published: March 2005

Obesity is a growing international health problem that has already reached epidemic proportions, particularly within the United States where a majority of the population is overweight or obese. Effective methods of treatment are needed, and should be taught to physicians by efficient means. There exists a disconnect between the rising obesity prevalence with its high toll on medical resources, and the lack of obesity education provided to practitioners in the course of their training. One particular shortfall is the lack of representation of obesity on standardized medical examinations. Physician attitudes toward obesity are influenced by their lack of familiarity with the management of the disease. This may include dietary restriction, increasing physical activity, behavior modification, pharmacotherapy, and surgical interventions. Thus, curricular changes in the medical education of obesity could help reduce morbidity and mortality associated with this disease.
Asymmetry in host and parasitoid diffuse coevolution: when the red queen has to keep a finger in more than one pie
Authors: Lapchin Laurent , Guillemaud Thomas
Published: March 2005

Background

Coevolution between pairs of antagonistic species is generally considered an endless "arms race" between attack and defense traits to counteract the adaptive responses of the other species.

Presentation of the hypothesis

When more than two species are involved, diffuse coevolution of hosts and parasitoids could be asymmetric because consumers can choose their prey whereas preys do not choose their predator. This asymmetry may lead to differences in the rate of evolution of the antagonistic species in response to selection. The more long-standing the coevolution of a given pair of antagonistic populations, the higher should be the fitness advantage for the consumer. Therefore, the main prediction of the hypothesis is that the consumer trophic level is more likely to win the coevolution race.

Testing the hypothesis

We propose testing the asymmetry hypothesis by focusing on the tritrophic system plant/aphid/aphid parasitoid. The analysis of the genetic variability in the virulence of several parasitoid populations and in the defenses of several aphid species or several clones of the same aphid species could be compared. Moreover, the analysis of the neutral population genetic structure of the parasitoid as a function of the aphid host, the plant host and geographic isolation may complement the detection of differences between host and parasitoid trophic specialization.

Implications of the hypothesis

Genetic structures induced by the arms race between antagonistic species may be disturbed by asymmetry in coevolution, producing neither rare genotype advantages nor coevolutionary hotspots. Thus this hypothesis profoundly changes our understanding of coevolution and may have important implications in terms of pest management.
Proliferation and differentiation potential of chondrocytes from osteoarthritic patients
Authors: Tallheden Tommi , Bengtsson Catherine , Brantsing Camilla , Sjögren-Jansson Eva , Carlsson Lars , Peterson Lars , Brittberg Mats , Lindahl Anders
Published: March 2005

Autologous chondrocyte transplantation (ACT) has been shown, in long-term follow-up studies, to be a promising treatment for the repair of isolated cartilage lesions. The method is based on an implantation of in vitro expanded chondrocytes originating from a small cartilage biopsy harvested from a non-weight-bearing area within the joint. In patients with osteoarthritis (OA), there is a need for the resurfacing of large areas, which could potentially be made by using a scaffold in combination with culture-expanded cells. As a first step towards a cell-based therapy for OA, we therefore investigated the expansion and redifferentiation potential in vitro of chondrocytes isolated from patients undergoing total knee replacement. The results demonstrate that OA chondrocytes have a good proliferation potential and are able to redifferentiate in a three-dimensional pellet model. During the redifferentiation, the OA cells expressed increasing amounts of DNA and proteoglycans, and at day 14 the cells from all donors contained type II collagen-rich matrix. The accumulation of proteoglycans was in comparable amounts to those from ACT donors, whereas total collagen was significantly lower in all of the redifferentiated OA chondrocytes. When the OA chondrocytes were loaded into a scaffold based on hyaluronic acid, they bound to the scaffold and produced cartilage-specific matrix proteins. Thus, autologous chondrocytes are a potential source for the biological treatment of OA patients but the limited collagen synthesis of the OA chondrocytes needs to be further explained.
Weighting by heritability for detection of quantitative trait loci with microarray estimates of gene expression
Authors: Manly Kenneth F , Wang Jintao , Williams Robert W
Published: March 2005

Heritable differences in transcribed RNA levels can be mapped as quantitative trait loci (QTLs). Transcribed RNA levels are often measured by hybridization to microarrays of oligonucleotide probes, in which each transcript is represented by multiple probes. The use of recombinant inbred lines allows an estimate of the heritability of expression measured by individual probes. This heritability varies greatly. We have tested heritability-weighted averages to define expression of a transcript and found that these allow detection of more QTLs than previously described methods.
Tumor Necrosis Factor-α Decreases Akt Protein Levels in 3T3-L1 Adipocytes via the Caspase-Dependent Ubiquitination of Akt
Authors: Medina Edward A. , Afsari Robert R. , Ravid Tommer , Castillo S. Sianna , Erickson Kent L. , Goldkorn Tzipora
Published: March 2005

TNF-α is a mediator of insulin resistance in sepsis, obesity, and type 2 diabetes and is known to impair insulin signaling in adipocytes. Akt (protein kinase B) is a crucial signaling mediator for insulin. In the present study we examined the posttranslational mechanisms by which short-term (<6-h) exposure of 3T3-L1 adipocytes to TNF-α decreases Akt levels. TNF-α treatment both increased the ubiquitination of Akt and decreased its protein level. The decrease in protein was associated with the presence of an (immunoreactive) Akt fragment after TNF-α treatment, indicative of Akt cleavage. The broad-spectrum caspase inhibitor t-butoxycarbonyl-Asp(O-Me)-fluoromethyl ketone markedly suppressed these effects of TNF-α. The caspase-6 inhibitor Z-Val-Glu(OMe)-Ile-Asp(OMe)-CH2F potently suppressed Akt ubiquitination, degradation, and fragment formation, whereas the proteasome inhibitor Z-Leu-Leu-Leu-CHO modestly attenuated the decline in Akt levels. Exposure to TNF-α also enhanced the association of Akt with an E3 ligase activity. Adipocytes preexposed to TNF-α for 5 h and then stimulated with insulin for 30 min exhibited decreased levels of Akt, phosphorylated Akt, as well as phosphorylated Mdm2, which is a known direct substrate of Akt, and glucose uptake. Caspase inhibition attenuated these inhibitory effects of TNF-α. Collectively, our results suggest that TNF-α induces the caspase-dependent degradation of Akt via the cleavage and ubiquitination of Akt, which results in its degradation through the 26S proteasome. Furthermore, the caspase- and proteasome-mediated degradation of Akt due to TNF-α exposure leads to impaired Akt-dependent insulin signaling in adipocytes. These findings expand the mechanism by which TNF-α impairs insulin signaling.
The Use of Peptide Nucleic Acids for In Situ Identification of Human Chromosomes
Authors: Pellestor Franck , Paulasova Petra , Macek Milan , Hamamah Samir
Published: March 2005

The peptide nucleic acids (PNAs) constitute a remarkable new class of synthetic nucleic acid analogues, based on their peptide-like backbone. This structure gives to PNAs the capacity to hybridize with high affinity and specificity to complementary RNA and DNA sequences and a great resistance to nucleases and proteinases. Originally conceived as ligands for the study of double-stranded DNA, the unique physicochemical properties of PNAs have led to the development of a large variety of research and diagnostic assays, including antigene and antisense therapy, genome mapping, and mutation detection. Over the past few years, PNAs have been shown to be powerful tools in cytogenetics for the rapid in situ identification of human chromosomes and the detection of aneuploidies. Recent studies have reported the successful use of chromosome-specific PNA probes on human lymphocytes, amniocytes, and spermatozoa, as well as on isolated oocytes and blastomeres. Multicolor PNA protocols have been described for the identification of several human chromosomes, indicating that PNAs could become a powerful complement to FISH for in situ chromosomal investigation.
Expression and proteasomal degradation of the major vault protein (MVP) in mammalian oocytes and zygotes
Authors: Sutovsky Peter , Manandhar Gaurishankar , Laurincik Jozef , Letko Juraj , Caamaño Jose Nestor , Day Billy N , Lai Liangxue , Prather Randall S , Sharpe-Timms Kathy L , Zimmer Randall , Sutovsky Miriam
Published: March 2005

Major vault protein (MVP), also called lung resistance-related protein is a ribonucleoprotein comprising a major part (>70%) of the vault particle. The function of vault particle is not known, although it appears to be involved in multi-drug resistance and cellular signaling. Here we show that MVP is expressed in mammalian, porcine, and human ova and in the porcine preimplantation embryo. MVP was identified by matrix-assisted laser-desorption ionization-time-of-flight (MALDI-TOF) peptide sequencing and Western blotting as a protein accumulating in porcine zygotes cultured in the presence of specific proteasomal inhibitor MG132. MVP also accumulated in poor-quality human oocytes donated by infertile couples and porcine embryos that failed to develop normally afterin vitrofertilization or somatic cell nuclear transfer. Normal porcine oocytes and embryos at various stages of preimplantation development showed mostly cytoplasmic labeling, with increased accumulation of vault particles around large cytoplasmic lipid inclusions and membrane vesicles. Occasionally, MVP was associated with the nuclear envelope and nucleolus precursor bodies. Nucleotide sequences with a high degree of homology to human MVP gene sequence were identified in porcine oocyte and endometrial cell cDNA libraries. We interpret these data as the evidence for the expression and ubiquitin-proteasome-dependent turnover of MVP in the mammalian ovum. Similar to carcinoma cells, MVP could fulfill a cell-protecting function during early embryonic development.
The IGF system in the neonatal ovine uterus
Authors: Hayashi Kanako , Carpenter Karen D , Welsh Thomas H , Burghardt Robert C , Spicer Leon J , Spencer Thomas E
Published: March 2005

Postnatal development of the ovine uterus primarily involves uterine gland morphogenesis or adenogenesis. Adenogenesis involves the budding differentiation of the glandular epithelium (GE) from the luminal epithelium (LE) and then GE proliferation and coiling/branching morphogenetic development within the stroma between birth (postnatal day or PND 0) and PND 56. Insulin-like growth factor (IGF)-I and IGF-II mRNAs were previously found to be expressed only in the endometrial stroma, whereas the IGF receptor (IGF-1R) mRNA was most abundant in epithelia and in stroma, suggesting that an intrinsic IGF system regulates postnatal development of the uterus. Given that the biological activities of IGFs are modulated by a family of six IGF binding proteins (IGFBPs) and specific proteases, the objective was to determine the effects of age and estrogen disruption on expression of IGFs, IGFBPs and pregnancy-associated plasma protein A (PAPP-A or IGFBP-4 protease) in the ovine uterus. In Study One, circulating levels of IGF-I and IGF-II in the serum of neonatal ewes did not change between PND 0 and PND 56. Levels of immunoreactive IGF-I, IGF-II and IGF-1R protein were most abundant on the apical surface of the endometrial LE and GE. RT-PCR analyses detected expression of IGFBPs (3, 4, 5 and 6) as well as PAPP-A mRNAs in the uterus, but not IGFBP-1 and IGFBP-2 mRNAs. IGFBP-3 and IGFBP-4 mRNAs were expressed specifically in the endometrial stroma and myometrium and increased after birth. PAPP-A mRNA was expressed specifically in the endometrial stroma and increased after birth. In Study Two, ewes were treated from birth with estradiol-17β valerate (EV), which reduces uterine growth and inhibits endometrial adenogenesis. On PNDs 14 and 56, IGFBP-3 mRNA was decreased in the uterus of EV-treated ewes, but IGF-1R and IGFBP-4 mRNAs were not affected. PAPP-A mRNA was increased by EV treatment on PND 14, but decreased on PND 56. These results support the hypothesis that an intrinsic IGF system in the uterus regulates epithelial–stromal interactions important for postnatal uterine growth and endometrial gland morphogenesis in the sheep.
Immunohistochemical studies on the progesterone receptor (PR) in the sow uterus during the oestrous cycle and in inseminated sows at oestrus and early pregnancy
Authors: Sukjumlong S , Dalin A-M , Sahlin L , Persson E
Published: March 2005

Physiological changes in the sow uterus involve the regulation by progesterone and its receptor proteins (PR). Therefore, the aim of the present study was to investigate the localization of PR during different stages of the oestrous cycle and in inseminated sows during early pregnancy by use of immunohistochemistry. Uterine samples were collected from cyclic and inseminated sows at different stages of the oestrous cycle and early pregnancy. The samples were fixed in 10% formaldehyde and embedded in paraffin. Immunohistochemistry was done by use of a mouse monoclonal antibody to PR. The highest PR immunostaining in the surface epithelium was observed at oestrus/5–6 h after artificial insemination (AI) and early dioestrus/70 h after AI. In the glandular epithelium, the highest level of PR was found at oestrus with the lowest at late dioestrus/d 19. Higher levels of PR were observed in inseminated groups compared with cyclic sows. In the myometrium, a high level of PR was found at oestrus, while stromal PR cells were constantly present throughout the oestrous cycle and at different stages of early pregnancy. In conclusion, this study shows that the immunopresence of PR in the sow uterus differed between uterine compartments at the same reproductive stage. Differences were also found for some uterine compartments between cyclic and inseminated/early pregnant sows. The relatively consistent immunostaining of PR in the stroma strengthens a stromal role in the regulation of physiological activities in the sow uterus during the oestrous cycle as well as early pregnancy.
Structural changes and thermal expansion behavior of ultrafine titanium powders during compaction and heating
Authors: Panigrahi B.B. , Godkhindi M.M.
Published: March 2005

This work represents an attempt to understand the nature of micron and attrition milled nano-sized titanium powders on two different aspects, i.e., pressure-induced phase change and thermal expansion. Contraction in the volume of unit cell in terms of decrease in interplaner spacing (d) has been observed in both powders and tends to restore upon annealing. At a given pressure, nano titanium shows a smaller decrease indrelative to micron titanium. The stress analysis of the compacts indicates higher value of residual stresses and deformations in micron powder than in nano powder. The dilatometric study reveals, first, the release of internal stresses and entrapped gases causes huge expansion in nanopowder compacts during heating. Secondly, there is no significant difference in the expansion coefficients of sintered micro- and nanocrystalline titanium samples.
Effect of solder bump geometry on the microstructure of Sn–3.5 wt% Ag on electroless nickel immersion gold during solder dipping
Authors: Huang Zhiheng , Conway Paul P. , Liu Changqing , Thomson Rachel C.
Published: March 2005

Continuous miniaturization of solder joints in high-density packaging makes it important to study how the joint size could affect the solder microstructure and thereby the subsequent in-service reliability. In this study, a printed circuit board with electroless nickel immersion gold (i.e., Au/Ni–P) over Cu bond pads of size approximately ∼80 μm and ∼1500 μm in diameter was dipped into a Sn–3.5Ag solder bath. The study shows that the smaller bumps, which cool more quickly, include much finer Ag3Sn particles. In addition, substantial differences in the thickness of the interfacial intermetallics and the microstructure for different dipping times are observed for different bump sizes. The results from a combined thermodynamic–kinetic model also suggest that the solder bump geometry can influence the dissolution kinetics of the pad metal into the molten solder and therefore the microstructure at the solder-pad interface and within the bulk solder.
Effect of solution pH on the accelerated cracking of nanoporous thin-film glasses
Authors: Guyer Eric P. , Dauskardt Reinhold H.
Published: March 2005

Hybrid organic–inorganic nanoporous thin-film glasses are extremely fragile and prone to stress-corrosion cracking in reactive environments. This has limited their integration as ultra low dielectric constant layers in high density integrated circuits. We demonstrate how crack growth is influenced by non-buffered aqueous solutions and show that with increasing pH, crack-growth rates are significantly accelerated. Interestingly, a crack growth regime limited by the transport of hydroxide ions to the crack tip was observed. Existing models commonly used to predict crack growth are shown to over estimate the experimental data by 6 orders of magnitude. We rationalize this behavior in terms of a significant difference in the crack tip solution chemistry as compared to that of the bulk and propose both chemical reaction and transport mechanisms to support this hypothesis.
Highly dense and compositionally inhomogeneous nano-agglomerates in an epitaxial La0.8Sr0.2MnO3 thin film grown on (100)SrTiO3
Authors: Zhu Y.L. , Ma X.L. , Li D.X. , Lu H.B. , Chen Z.H. , Yang G.Z.
Published: March 2005

Microstructures in the thin film of La0.8Sr0.2MnO3 grown on (100) SrTiO3 by laser molecular beam epitaxy were characterized by transmission electron microscopy. Highly dense and dimensionally uniform nano-agglomerates were found embedded in thin film of La0.8Sr0.2MnO3. High-angle angular dark-field imaging, elemental mapping, and compositional analysis revealed that the nano-agglomerates are rich in manganese and poor in lanthanum. The ratio of Mn/La in the nano-agglomerates fluctuates. A salient feature of this compositional fluctuation within the nanoscale isthe formation of cubic MnO phase, which appears as the core of the nano-agglomerates.The La0.8Sr0.2MnO3 film is domain-oriented and two domains were identified on the basis of orthorhombic lattice. The orientation relationships between La0.8Sr0.2MnO3 domains and MnO were determined as [010]LSMO,1//[001]MnO and (100)LSMO,1//(110)MnO; [101]LSMO,2//[001]MnO and (010)LSMO,2//(100)MnO. The domain structuresand compositional inhomogeneities within nanoscale result in a textured microstructure, which is one of the most important parameters for tuning electronic properties in colossal magnetoresistance oxides.
Ferroelectric and piezoelectric properties of highly oriented Pb(Zr,Ti)O3 film grown on Pt/Ti/SiO2/Si substrate using conductive lanthanum nickel nitrate buffer layer
Authors: Choi Jong-Jin , Park Gun-Tae , Park Chee-Sung , Kim Hyoun-Ee
Published: March 2005

The orientation and electrical properties of Pb(Zr,Ti)O3 thin films deposited on a Pt/Ti/SiO2/Si substrate using lanthanum nickel nitrate as a conductive buffer layer were analyzed. The lanthanum nickel nitrate buffer layer was not only electrically conductive but also effective in controlling the texture of the lead zirconate titanate (PZT) thin film. The role of the lanthanum nickel nitrate buffer layer and its effects on the orientation of the PZT thin film were analyzed by x-ray diffraction, electron beam back-scattered diffraction, and scanning electron microscopy. The annealed lanthanum nickel nitrate buffer layer was sufficiently conducting for use in longitudinal electrode configuration devices. The dielectric, ferroelectric, and piezoelectric properties of the highly (100) oriented PZT films grown with the lanthanum nickel nitrate buffer layer were measured and compared with those of (111) and (100) oriented PZT films deposited without a buffer layer.
Effect of starting powder morphology on AlN prepared by combustion reaction
Authors: Lee Jaeryeong , Lee Ikkyu , Kim Dongjin , Ahn Jonggwan , Chung Hunsaeng
Published: March 2005

The particle size and shape effects of starting raw powders on the synthesis of aluminum nitride by combustion reaction technique were investigated with four sizes of AlN powder as diluent and two shapes of Al powder as reactant. It was found that the structure of beds of starting particles significantly affected the pore channels for nitrogen gas accessibility into a mixture compact and the passages for combustion wave propagation through particles, resulting in changes of AlN product morphology and purity. Through control of the starting particle size and shape, high-purity (over 98%) AlN products several tens of microns in size were synthesized.
Structural characterization of the fullerene nanotubes prepared by the liquid–liquid interfacial precipitation method
Authors: Miyazawa Kun'ichi , Minato Jun-ichi , Yoshii Tetsuro , Fujino Masahisa , Suga Tadatomo
Published: March 2005

Fine tubular fibers composed of C60 and C70 fullerene molecules were successfully fabricated by the liquid–liquid interfacial precipitation method. The walls of the tubular fibers were crystalline, and the fullerene molecules were densely packed along the growth axis of tube wall. The tubular structures are called “fullerene nanotubes.” The inner diameter and the outer diameter of C70 tubes showed a linear relationship, suggesting a constant wall thickness of the tubes. The tubular structures composed of C70 molecules could be formed when their diameter was larger than about 240 nm. The fullerene tubes were successfully fabricated by using a C60-C70 soot as well. The formation of fullerene nanotubes can be understood by assuming a mechanism of core dissolution of the solvated fullerene nanowhiskers.
Elastic moduli of grain boundaries in nanocrystalline MgO ceramics
Authors: Yeheskel Ori , Chaim Rachman , Shen Zhijian , Nygren Mats
Published: March 2005

Dense MgO ceramics with nanometer to submicrometer grain size were fabricated by high-temperature hot-isostatic pressing, low-temperature hot-pressing, and spark plasma sintering. The elastic properties were determined by sound wave velocity measurements. Young's and shear moduli of nanocrystalline MgO were lower by 13% than those with submicrometer grain size. Softening of the elastic properties was analyzed and related to the lower density and lower elastic moduli of the grain boundaries compared to the crystal interior. Young's and shear moduli of the grain boundaries were evaluated as 90 and 34 GPa, respectively. This leads to a more than 3-fold decrease in the effective elastic moduli with the decrease of grain size into the nanometer range.
Characterization of high-pressure sintered C60 nanowhiskers and C60 powder
Authors: Minato Jun-ichi , Miyazawa Kun'ichi , Suga Tadatomo , Kanda Hisao , Akaishi Minoru , Yamaura Kazunari , Muromachi Eiji , Kakisawa Hideki
Published: March 2005

C60 nanowhiskers fabricated by liquid–liquid interfacial precipitation method and pristine C60 powder were sintered at 800 °C under 5.5 GPa for 2 h. The specimens showed high micro-Vickers hardness about 1100 kg/mm2 and electrical resistivity as low as several Ωm. Structural characterization by x-ray diffraction, high-resolution transmission electron microscopy, Fourier transform infrared, and Raman spectroscopy revealed that most of C60 molecules were broken to form turbostratic graphite by high-pressure and high-temperature treatment. Comparison with the pristine C60 powder sintered under the same conditions suggests that the structural change depends microscopically on the C60 molecules, but the size and the morphology of the starting material also affect the macroscopic sintering process.
Size-driven domain reorientation in hydrothermally derived lead titanate nanoparticles
Authors: Ye Zhiyuan , Slamovich Elliott B. , King Alexander H.
Published: March 2005

High-resolution transmission electron microscopy studies of hydrothermally derived platelike lead titanate nanoparticles reveal that below a critical size of approximately 70 nm, the single ferroelectric domain polarization axis reorients from perpendicular to parallel to the plate. We suggest that during particle growth, ions in the hydrothermal processing medium compensate for the ferroelectric depolarization energy. When the processing medium is removed by washing and drying, single domain nanoparticles minimize their depolarization energy by c-axis flipping.
Octahedral microporous phases Na2Nb2−xTixO6−x(OH)x·H2O and their related perovskites: Crystal chemistry, energetics, and stability relations
Authors: Xu Hongwu , Navrotsky Alexandra , Nyman May D. , Nenoff Tina M.
Published: March 2005

A family of microporous phases with compositions Na2Nb2−xTixO6−x(OH)x⋅H2O (0 ≤ x ≤ 0.4) transform to Na2Nb2−xTixO6−0.5x perovskites upon heating. In this study, we have measured the enthalpies of formation of the microporous phases and their corresponding perovskites from the constituent oxides and from the elements by drop solution calorimetry in 3Na2O·4MoO3 solvent at 974 K. As Ti/Nb increases, the enthalpies of formation for the microporous phases become less exothermic up to x = ∼0.2 but then more exothermic thereafter. In contrast, the formation enthalpies for the corresponding perovskites become less exothermic across the series. The energetic disparity between the two series can be attributed to their different mechanisms of ionic substitutions: Nb5+ + O2− → Ti4+ + OH− for the microporous phases and Nb5+ → Ti4+ + 0.5VO.. for the perovskites. From the calorimetric data for the two series, the enthalpies of the dehydration reaction, Na2Nb2−xTixO6−x(OH)x⋅H2O → Na2Nb2−xTixO6−0.5x + H2O, have been derived, and their implications for phase stability at the synthesis conditions are discussed.
Early interaction between Fe–Cr alloy metallic interconnect and Sr-doped LaMnO3 cathodes of solid oxide fuel cells
Authors: Jiang S.P. , Zhang Sam , Zhen Y.D.
Published: March 2005

The initial stages of the interaction between the Fe–Cr alloy metallic interconnect and Sr-doped LaMnO3 (LSM) electrode of solid oxide fuel cells (SOFC) were investigated under cathodic polarization at the temperature range of 700–900 °C. Cr deposits on the Y2O3–ZrO2 (YSZ) electrolyte surface increased with the polarization time. However, it was observed that at the early stages of the reaction, there is no preferential Cr deposition at the three-phase boundary areas at the LSM electrode/YSZ electrolyte interface region. With the decrease of the temperature the Cr deposition reduced significantly, probably due to the significant reduction in the partial pressure of the gaseous Cr species and the cationic diffusivities in the LSM electrode. The results clearly demonstrated that the deposition of Cr species at the LSM electrode/YSZ electrolyte is basically a chemical reaction and kinetically controlled by the nucleation reaction between the gaseous Cr species and the Mn2+ species generated under cathodic polarization.
Cleft Palate and Beckwith-Wiedemann Syndrome
Authors: Laroche Carine , Testelin Sylvie , Devauchelle Bernard
Published: March 2005

Objective

Patients with Beckwith-Wiedemann syndrome suffer numerous anomalies, which vary somewhat from case to case. Cleft palate in combination with this syndrome has rarely been reported in the literature. Through two cases, this report examines the staging of the surgical repairs and the role of macroglossia in cleft palate and the consequences of the scarred palate on mandibular development.

Results

Of four patients with Beckwith-Wiedemann syndrome, only two had a cleft palate. The timing of the repair in these two children was different. Speech development was satisfactory in the first case but mediocre in the second. This result seemed to be related to a poor social environment. Mandibular prognathism persisted in both cases.

Conclusion

The treatment of patients with cleft palate and Beckwith-Wiedemann syndrome remains complex. It is preferable not to operate on a cleft palate before performing a tongue reduction plasty, but rather to combine these two surgical interventions. This would reduce the risks of anesthesia and enable the palate to heal more efficiently. Surgical treatment should be performed after the age of 6 months and before problems in speech development occur. An orthognathic surgery at adolescence could be performed if prognathism persists. While the origin of the cleft palate is still being discussed, we cannot claim that macroglossia is related to the development of cleft palate, nor that the scarred palate has an impact on the mandibular development.
Application of Limited Cone Beam Computed Tomography to Clinical Assessment of Alveolar Bone Grafting: A Preliminary Report
Authors: Hamada Yoshiki , Kondoh Toshirou , Noguchi Kazuhide , Iino Mitsuyoshi , Isono Hiroaki , Ishii Hiroaki , Mishima Akira , Kobayashi Kaoru , Seto Kanichi
Published: March 2005

Objectives

The aim of this study was to demonstrate the clinical applicability of limited cone beam computed tomography (Dental 3D-CT) for assessment of bone-grafted alveolar cleft.

Patients and Methods

Seventeen bone bridges were examined after alveolar bone grafting in 13 patients with cleft lip and palate. All bone bridges, including cleft-adjacent teeth, were examined by plain radiography and the Dental 3D-CT imaging system.

Results

The plain radiographs showed the approximate condition of the bone bridge and cleft-adjacent teeth. The Dental 3D-CT images clearly showed precise three-dimensional (3D) morphology of the bone bridge, 3D relationships between the bone bridge and the roots of cleft-adjacent teeth, and their periodontal condition. In addition, the conditions surrounding dental implants installed in the bone bridge could be observed three-dimensionally.

Conclusions

The results indicate that the Dental 3D-CT imaging system is suitable for clinical assessment of alveolar bone grafting before and after installation of dental implants or orthodontic treatment of the cleft-adjacent teeth.
Report of Altered Sensation in Patients with Cleft Lip
Authors: Essick Greg K. , Dorion Craig , Rumley Seth , Rogers Lyna , Young Michael , Trotman Carroll-Ann
Published: March 2005

Objective

To determine whether patients with cleft lip have normal perioral sensation.

Design

Each subject was carefully questioned about the following: sensation in the face at rest, light touch of different areas, and sensation in natural situations (e.g., exposure to cold weather) that reveal sensory abnormalities. A cotton-tip applicator stick was stroked lightly across the facial skin. The subject's descriptions of the evoked sensations were used to identify and outline areas with abnormal sensation.

Setting

Data were obtained from subjects participating in a longitudinal, university-based study of the functional outcomes of lip revision surgery.

Patients

Seventeen patients with cleft lip and 12 control subjects (aged 7 to 22 years, mean 12.9 years) participated.

Results

In contrast to control subjects, 9 of 16 patients (56%) reported loss in sensation, described as decreased touch, scratch, tickle, or tingle intensity. Six other patients (38%) reported additional sensation, described as increased scratch, tickle, or tingle intensity. In eight patients, the altered sensation was restricted to the skin area flanking and including the visible scar, encompassing no more than 25% of the total area bound by the inferior nose, nasolabial grooves and inferior vermilion. In seven patients (unilateral cleft), the altered area extended to the contralateral, noncleft side of the upper lip or onto the philtrum.

Conclusions

In contrast to the literature, sensation in the upper lip of many patients with cleft lip is not normal. Loss in sensation is exhibited most commonly and limited largely to the skin overlying tissues traumatized during reconstructive surgery.
A New Three-Dimensional Method of Assessing Facial Volumetric Changes after Orthognathic Treatment
Authors: Hajeer Mohammad Y. , Mao Zhili , Millett Declan T. , Ayoub Ashraf F. , Siebert Jan Paul
Published: March 2005

Objective

To validate a new method of facial volumetric assessment that is dependent on the use of stereophotogrammetric models and a software-based Facial Analysis Tool.

Design

The method was validated in vitro with three-dimensional (3D) models of a lifelike plastic female dummy head and in vivo with a male-subject head.

Methods

Thirty facial silicone explants were added in the nasal and perioral regions of each head, and their volumes were obtained by three different algorithms. These were compared with the actual values obtained by a “water displacement” method.

Results

The least mean error was found with the “tetrahedron formation” method followed by the “projection” method and the “back-plane construction” method. The error with the tetrahedron formation method was 0.071 cm3 (95% confidence interval [CI]: −0.074 to 0.2161 cm3) with the in vitro models and 0.314 cm3 (95% CI: −0.080 to 0.708 cm3) with the in vivo models. The increased volumetric assessment error observed in vivo was attributed to the registration procedure and possible changes in facial expression.

Conclusions

These results encourage the use of this method in the 3D assessment of orthognathic surgical outcome, provided a standardized facial expression is used for image acquisition.
Morphology of the Auditory Tube and Palatal Muscles in a Case of Bilateral Cleft Palate
Authors: Arnold W. H. , Nohadani N. , Koch K. H. H.
Published: March 2005

Objective

There is an increased incidence of otitis media in children with cleft palate, which may be related to the pathology of the auditory tube and palatal muscles. In the present study, the head of a human on term born fetus with bilateral palatal cleft was serially sectioned and the anatomy of the auditory tube and palatal muscles were studied by computer-aided three-dimensional reconstruction.

Results

The results showed a nearly horizontal course of the auditory tube. The tensor veli palatini muscle had a bony attachment on either side. The levator veli palatini muscle also showed an abnormal course.

Conclusions

This abnormal course may result in obstruction of the auditory tube during contraction. These pathological findings may explain the higher frequency of otitis media in children with cleft palate.
Rac2-Deficient Hematopoietic Stem Cells Show Defective Interaction with the Hematopoietic Microenvironment and Long-Term Engraftment Failure
Authors: Jansen Michael , Yang Feng-Chun , Cancelas José A. , Bailey Jeff R. , Williams David A.
Published: March 2005

The hematopoietic-specific Rho GTPase, Rac2, regulates a variety of cellular functions including cell shape changes, motility, integrin-dependent adhesion, and apoptosis. In the study reported here, we demonstrate that wild-type (WT) hematopoietic stem cells/progenitors (HSC/P) preferentially engraft in nonablated Rac2−/− bone marrow. In addition, primitive Rac2−/− HSC/P transplanted into lethally irradiated WT recipients showed a significant competitive defect compared with WT cells. These defects appeared to be related to HSC/P-intrinsic defective microenvironment interactions, since Rac2−/− cells showed less adhesion to the femur bone marrow density 1 (FBMD-1) stromal cell line, a lower frequency of cobblestone area–forming cells, and lower performance in long-term marrow cultures in vitro when compared with WT cells. In contrast, primitive Rac2−/− hematopoietic cells exhibited normal progenitor colony formation in semisolid medium in vitro and normal proliferation in the steady state in vivo when compared with WT cells. Taken together, these data suggest that Rac2−/− stem/progenitor cells exhibit abnormal interaction with the hematopoietic microenvironment, which leads to defective long-term engraftment.
Identification, localization and functional in vitro and in vivo activity of oxytocin receptor in the rat penis
Authors: Zhang X H , Filippi S , Vignozzi L , Morelli A , Mancina R , Luconi M , Donati S , Marini M , Vannelli G B , Forti G , Maggi M
Published: March 2005

We recently found that the oxytocin receptor (OTR) is expressed in the human and rabbit corpus cavernosum and mediates contractility in vitro. The present study extended our investigations to the rat, and explored whether OTR regulates penile detumescence in vivo. Real-time RT-PCR quantitatively characterized the distribution of OTR mRNA in the male genital tract. Specific transcripts for OTR were expressed in all the tissues investigated. Penile expression of OTR was comparable to that observed in testis and prostate. Western blot analysis detected a single band of the expected molecular mass for OTR in all tissues examined, including rat penis. Expression of OTR protein in rat penile extracts was further confirmed by binding studies, using the OTR selective radiolabeled ligand 125I-OTA (Kd=17 ± 6.5 pM, Bmax=15.7 ± 5 fmoles/mg protein). OTR was immunolocalized to the endothelial and smooth muscle compartments of cavernous spaces and blood vessels. In rat corpus cavernosum strips, oxytocin (OT) and an OTR selective agonist ([Thr4,Gly7]OT) induced identical increases in tension, while different vasopressin agonists were less active. In vivo, OT intra-cavernous injection (ICI) dose-dependently inhibited intracavernous pressure (ICP) increase elicited by either electrical stimulation of the cavernous nerve or ICI of papaverine with similar IC50s (117.7 ± 37 mU). The OTR antagonist, atosiban, counteracted the contractile effect of OT both in vitro and in vivo. Atosiban alone significantly increased ICP at lower stimulation frequencies (2 Hz=P<0.001 and 4 Hz=P<0.05 vs control), but not at the maximal frequency (16 Hz). Our data showed that OTR is present in the rat penis and mediates contractility both in vitro and in vivo, therefore suggesting a role for OT in maintaining penile detumescence.
Hormone-driven mechanisms in the central nervous system facilitate the analysis of mammalian behaviours
Authors: Pfaff Donald
Published: March 2005

Hormonal effects on behaviours in animals and humans are now well enough understood for general statements about causal steps to be proposed. Facilitation or repression of a given behaviour by a given hormone can depend on the person’s genetic and developmental history, on the temporal and spatial parameters of the hormone’s administration, on the hormone’s metabolism and on the specific receptor isoform available in a given neuron. The gene for oestrogen receptor-alpha is required for an entire chain of behaviours essential for reproduction, from courtship through maternal behaviours. In order to show that it is possible to use endocrine tools to explain a mammalian behaviour, we analysed lordosis behaviour neuronal circuitry as well as the molecular mechanisms of its facilitation by oestrogens. The functional genomics of oestrogenic effects on lordosis arrange themselves in modules for neuronal Growth, Amplification (by progestins), Preparatory behaviours, Permissive actions by hypothalamic neurons, and Synchronization of mating behaviour with ovulation (GAPPS). A related four-gene micronet involving the amygdala and the paraventricular nucleus of the hypothalamus supports social recognition. Underlying all sociosexual behaviour is the fundamental arousal of brain and behaviour. Elementary arousal depends on a bilateral, bidirectional system universal among mammalian brains, and it can be altered by null deletion of the gene for oestrogen receptor-alpha. Future molecular and biophysical studies will specify how hormone effects in the brain change central nervous system state in such a manner as to alter the frequencies of entire sets of behavioural responses.
Selenium and endocrine systems
Authors: Beckett Geoffrey J , Arthur John R
Published: March 2005

The trace element selenium (Se) is capable of exerting multiple actions on endocrine systems by modifying the expression of at least 30 selenoproteins, many of which have clearly defined functions. Well-characterized selenoenzymes are the families of glutathione peroxidases (GPXs), thioredoxin reductases (TRs) and iodothyronine deiodinases (Ds). These selenoenzymes are capable of modifying cell function by acting as antioxidants and modifying redox status and thyroid hormone metabolism. Se is also involved in cell growth, apoptosis and modifying the action of cell signalling systems and transcription factors. During thyroid hormone synthesis GPX1, GPX3 and TR1 are up-regulated, providing the thyrocytes with considerable protection from peroxidative damage. Thyroidal D1 in rats and both D1 and D2 in humans are also up-regulated to increase the production of bioactive 3,5,3′-tri-iodothyronine (T3). In the basal state, GPX3 is secreted into the follicular lumen where it may down-regulate thyroid hormone synthesis by decreasing hydrogen peroxide concentrations. The deiodinases are present in most tissues and provide a mechanism whereby individual tissues may control their exposure to T3. Se is also able to modify the immune response in patients with autoimmune thyroiditis. Low sperm production and poor sperm quality are consistent features of Se-deficient animals. The pivotal link between Se, sperm quality and male fertility is GPX4 since the enzyme is essential to allow the production of the correct architecture of the midpiece of spermatozoa. Se also has insulin-mimetic properties, an effect that is probably brought about by stimulating the tyrosine kinases involved in the insulin signalling cascade. Furthermore, in the diabetic rat, Se not only restores glycaemic control but it also prevents or alleviates the adverse effects that diabetes has on cardiac, renal and platelet function.
Inequivalent representations of geometric relation algebras
Authors: Givant Steven
Published: March 2005

It is shown that the automorphism group of a relation algebra constructed from a projective geometry P is isomorphic to the collineation group of P. Also, the base automorphism group of a representation of over an affine geometry D is isomorphic to the quotient of the collineation group of D by the dilatation subgroup. Consequently, the total number of inequivalent representations of , for finite geometries P, is the sum of the numbers

where D ranges over a list of the non-isomorphic affine geometries having P as their geometry at infinity. This formula is used to compute the number of inequivalent representations of relation algebras constructed over projective lines of order at most 10. For instance, the relation algebra constructed over the projective line of order 9 has 56,700 mutually inequivalent representations.
Decomposition and infima in the computably enumerable degrees
Authors: Downey Rodney G. , Laforte Geoffrey L. , Shore Richard A.
Published: March 2005

Given two incomparable c.e. Turing degrees a and b, we show that there exists a c.e. degree c such that c = (a ∪ c) ∩ (b ∪ c), a ∪ c ∣ b ∪ c, and c < a ∪ b.
Solovay models and forcing extensions
Authors: Bagaria Joan , Bosch Roger
Published: March 2005

We study the preservation under projective ccc forcing extensions of the property of L(ℝ) being a Solovay model. We prove that this property is preserved by every strongly- absolutely-ccc forcing extension, and that this is essentially the optimal preservation result, i.e., it does not hold for absolutely-ccc forcing notions. We extend these results to the higher projective classes of ccc posets, and to the class of all projective ccc posets, using definably-Mahlo cardinals. As a consequence we obtain an exact equiconsistency result for generic absoluteness under projective absolutely-ccc forcing notions.
On Kueker simple theories
Authors: Shami Ziv
Published: March 2005

We show that a Kueker simple theory eliminates ∃∞ and densely interprets weakly minimal formulas. As part of the proof we generalize Hrushovski's dichotomy for almost complete formulas to simple theories. We conclude that in a unidimensional simple theory an almost-complete formula is either weakly minimal or trivially-almost-complete. We also observe that a small unidimensional simple theory is supersimple of finite SU-rank.
Synthesis, characterization and biological properties of vanadyl(IV) complexes of diclofenac and indomethacin: an experimental and theoretical study
Authors: Williams Patricia A. M. , Molinuevo María S. , Okulik Nora , Jubert Alicia H. , Etcheverry Susana B.
Published: March 2005

Two new vanadyl(IV) complexes with the non‐steroidal antiinflammatory drugs Indomethacin and Diclofenac were synthesized and characterized by elemental analysis, electronic, diffuse reflectance and FTIR spectroscopies and thermal behavior. The structures of the oxo‐vanadium(IV) complexes were obtained by carrying out ab initio calculations (B3LY/3–21G**) owing to the difficulties of obtaining single crystals of good quality for X‐ray studies. Indomethacin and Diclofenac did not cause any effect when tested on cellular proliferation in two osteoblast‐cell lines in culture (MC3T3E1 and UMR106). The biological effect of the complexes depends on the cellular type and on the nature of the coordinated ligands. Copyright © 2005 John Wiley & Sons, Ltd.
Comparison of beam theory and finite‐element analysis with in vivo bone strain data from the alligator cranium
Authors: Metzger Keith A. , Daniel William J.T. , Ross Callum F.
Published: March 2005

The mechanical behavior of the vertebrate skull is often modeled using free‐body analysis of simple geometric structures and, more recently, finite‐element (FE) analysis. In this study, we compare experimentally collected in vivo bone strain orientations and magnitudes from the cranium of the American alligator with those extrapolated from a beam model and extracted from an FE model. The strain magnitudes predicted from beam and FE skull models bear little similarity to relative and absolute strain magnitudes recorded during in vivo biting experiments. However, quantitative differences between principal strain orientations extracted from the FE skull model and recorded during the in vivo experiments were smaller, and both generally matched expectations from the beam model. The differences in strain magnitude between the data sets may be attributable to the level of resolution of the models, the material properties used in the FE model, and the loading conditions (i.e., external forces and constraints). This study indicates that FE models and modeling of skulls as simple engineering structures may give a preliminary idea of how these structures are loaded, but whenever possible, modeling results should be verified with either in vitro or preferably in vivo testing, especially if precise knowledge of strain magnitudes is desired. © 2005 Wiley‐Liss, Inc.