Placental Transfer of 18F-2-Deoxy-2-Fluoroglucose and 14C-4-Iodoantipyrine in Hypoxic Rats

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Two-scale competition in phase separation with shear

The behavior of a phase separating binary mixture in uniform shear flow is investigated by numerical simulations and in a renormalization group (RG) approach. Results show the simultaneous existence of domains of two characteristic scales. Stretching and cooperative ruptures of the network produce a rich interplay where the recurrent prevalence of thick and thin domains determines log-time periodic oscillations. A power law growth $R(t) \sim t^{\alpha}$ of the average domain size, with $\alpha =4/3$ and $\alpha = 1/3$ in the flow and shear direction respectively, is shown to be obeyed.Comment: 5 Revtex pages, 4 figure

A rare case of static bone cavity in the anterior mandibular region of a 10-year-old boy

INTRODUCTION: Static bone cavity (SBC) is a bone defect that develops as a result of localized pressure from tissues surrounding the mandible. It is most commonly observed in the mandibular angle of adult males caused by the submandibular gland. The condition is asymptomatic and requires no treatment. The frequency of onset is rare, especially in the anterior mandible, and SBC is extremely difficult to diagnose in children. PRESENTATION OF CASE: This report is on a case of SBC in the anterior mandible of a 10-year-old boy. The condition could not be diagnosed after panoramic radiograph and Magnetic Resonance Imaging (MRI) analyses. Computed-topography (CT) imagery revealed an oval-shaped depression 6 × 5 × 3 mm in size at the lingual apex of the mandibular left lateral tooth. Diagnosing the patient was difficult and a tumor was suspected. For treatment, the tumor-like lesion was resected and the fistula in the periosteum was sutured and closed. One year later, the defect on the lingual mandibular bone had ossified and recovered. CONCLUSION: The incidence of SBC in children is rare and the condition is difficult to diagnose because of the small size of the lesions, however in this study, CT imagery proved to be useful. SBC was detected in the subject in early childhood, and his postoperative course suggested that the lesion developed as a result of glandular tissues herniating through the periosteum and causing compression on the mandible, which resulted in bone resorption. In other words, herniation of normal salivary glandular tissues were a cause of SBC

Phase separation in an homogeneous shear flow: Morphology, growth laws and dynamic scaling

We investigate numerically the influence of an homogeneous shear flow on the spinodal decomposition of a binary mixture by solving the Cahn-Hilliard equation in a two-dimensional geometry. Several aspects of this much studied problem are clarified. Our numerical data show unambiguously that, in the shear flow, the domains have on average an elliptic shape. The time evolution of the three parameters describing this ellipse are obtained for a wide range of shear rates. For the lowest shear rates investigated, we find the growth laws for the two principal axis $R_\perp (t) \sim constant$, $R_\parallel(t) \sim t$, while the mean orientation of the domains with respect to the flow is inversely proportional to the strain. This implies that when hydrodynamics is neglected a shear flow does not stop the domain growth process. We investigate also the possibility of dynamic scaling, and show that only a non trivial form of scaling holds, as predicted by a recent analytical approach to the case of a non-conserved order parameter. We show that a simple physical argument may account for these results.Comment: Version accepted for publication - Physical Review

ELOVL6 Genetic Variation Is Related to Insulin Sensitivity: A New Candidate Gene in Energy Metabolism

BACKGROUND: The elongase of long chain fatty acids family 6 (ELOVL6) is an enzyme that specifically catalyzes the elongation of saturated and monounsaturated fatty acids with 12, 14 and 16 carbons. ELOVL6 is expressed in lipogenic tissues and it is regulated by sterol regulatory element binding protein 1 (SREBP-1). OBJECTIVE: We investigated whether ELOVL6 genetic variation is associated with insulin sensitivity in a population from southern Spain. DESIGN: We undertook a prospective, population-based study collecting phenotypic, metabolic, nutritional and genetic information. Measurements were made of weight and height and the body mass index (BMI) was calculated. Insulin resistance was measured by homeostasis model assessment. The type of dietary fat was assessed from samples of cooking oil taken from the participants' kitchens and analyzed by gas chromatography. Five SNPs of the ELOVL6 gene were analyzed by SNPlex. RESULTS: Carriers of the minor alleles of the SNPs rs9997926 and rs6824447 had a lower risk of having high HOMA_IR, whereas carriers of the minor allele rs17041272 had a higher risk of being insulin resistant. An interaction was detected between the rs6824447 polymorphism and the intake of oil in relation with insulin resistance, such that carriers of this minor allele who consumed sunflower oil had lower HOMA_IR than those who did not have this allele (P = 0.001). CONCLUSIONS: Genetic variations in the ELOVL6 gene were associated with insulin sensitivity in this population-based study

Catechol-O-methyltransferase (COMT) polymorphisms modulate working memory in individuals with schizophrenia and healthy controls

Objective: Cognitive impairment is a core feature of schizophrenia, related to dopaminergic dysfunction in the prefrontal cortex (PFC). It is hypothesized that functional single nucleotide polymorphism (SNP) rs4680 of the catechol-O-methyltransferase (COMT) gene could mediate the relationship between cognition and dopamine activity in the PFC. Other COMT SNPs could also play a role. Methods: We evaluated the role of three COMT SNPs (rs737865, rs165599, and rs4680) in schizophrenia and their impact on three working memory tasks. For genetic association analyses, 212 individuals with schizophrenia and 257 healthy controls (HCs) were selected. The Visual Working Memory (VWM) Task, Keep Track Task, and Letter Memory Task were administered to 133 schizophrenics and 93 HCs. Results: We found a significant association of rs737865, with the GG genotype exerting a protective effect and the GA haplotype (rs4680/rs165599) exerting a risk effect for schizophrenia. COMT rs4680 AA carriers and rs737865 AA carriers scored lowest on the Keep Track Task. When the genotype* group interaction effect was evaluated, rs165599 exerted opposite effects for VWM and Keep Track task performance in patients and controls, with AA carriers scoring lowest on both tests among controls, but highest among patients. Conclusion: These data support the hypothesis that COMT polymorphisms may be associated with schizophrenia and modulate cognition in patients and controls.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP), BrazilUniv Fed Sao Paulo UNIFESP, Dept Psiquiatria, Sao Paulo, SP, BrazilFMABC, Dept Saude Colet, Santo Andre, SP, BrazilUniv Fed Sao Paulo, Lab Interdisciplinar Neurociencias Clin LiNC, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Morfol & Genet, Disciplina Genet, Sao Paulo, SP, BrazilCtr Univ Fundcao Inst Ensino Osasco UNIFIEO, Dept Psicol Educ, Osasco, SP, BrazilUniv Fed Sao Paulo, Dept Psicobiol, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Dept Psiquiatria, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Lab Interdisciplinar Neurociencias Clin LiNC, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Morfol & Genet, Disciplina Genet, Sao Paulo, SP, BrazilUniv Fed Sao Paulo, Dept Psicobiol, Sao Paulo, SP, BrazilFAPESP: 2007/58736-1FAPESP: 2011/50740-5Web of Scienc

Phase separating binary fluids under oscillatory shear

We apply lattice Boltzmann methods to study the segregation of binary fluid mixtures under oscillatory shear flow in two dimensions. The algorithm allows to simulate systems whose dynamics is described by the Navier-Stokes and the convection-diffusion equations. The interplay between several time scales produces a rich and complex phenomenology. We investigate the effects of different oscillation frequencies and viscosities on the morphology of the phase separating domains. We find that at high frequencies the evolution is almost isotropic with growth exponents 2/3 and 1/3 in the inertial (low viscosity) and diffusive (high viscosity) regimes, respectively. When the period of the applied shear flow becomes of the same order of the relaxation time $T_R$ of the shear velocity profile, anisotropic effects are clearly observable. In correspondence with non-linear patterns for the velocity profiles, we find configurations where lamellar order close to the walls coexists with isotropic domains in the middle of the system. For particular values of frequency and viscosity it can also happen that the convective effects induced by the oscillations cause an interruption or a slowing of the segregation process, as found in some experiments. Finally, at very low frequencies, the morphology of domains is characterized by lamellar order everywhere in the system resembling what happens in the case with steady shear.Comment: 1 table and 12 figures in .gif forma

The effect of fibroblast growth factor 7 on human dental pulp stem cells for differentiation to AQP5-positive and αSMA-positive cells in vitro and in vivo

OBJECTIVES: Transplantation of stem cells into wounds has become popular in regeneration therapies. As stem cells for transplantation, human dental pulp stem cells (hDPSCs) are known to be pluripotent cells that are relatively easy to collect from the pulp of deciduous or wisdom teeth. The purpose of this study was to investigate whether hDPSCs treated with fibroblast growth factor 7 (FGF7) would contribute to the regeneration of wounded rat submandibular glands (SMGs). MATERIALS AND METHODS: In in vitro studies, hDPSCs were treated with or without FGF7 and mRNA expression levels were examined at days 3, 7 and 14 using qRT‐PCR. The target genes analyzed were BMI1 as an undifferentiated marker, AQP5 as an acinar cell marker, CK19 as a ductal epithelial cell marker, αSMA as a myoepithelial cell marker and VIMENTIN as a fibroblast marker. In in vivo studies, hDPSCs treated with or without FGF7 for 14 days were mixed with type I collagen gels and were transplanted into wounded rat SMGs. Hematoxylin–Eosin and immunohistochemical staining were performed at days 3 and 7, and the numbers of positive cells were counted. The primary antibodies used were against BMI1, AQP5, αSMA, PanCK and VIMENTIN. RESULTS: In the in vitro studies, mRNA levels of BMI1 were decreased and αSMA were increased at days 3, 7 and 14, while AQP5 was increased at day 14 in the FGF7 group. In the in vivo studies, the proliferation of hDPSCs and cell islands was observed at day 7 in the FGF7 group. Few BMI1‐positive cells were observed, while numbers of AQP5‐positive and αSMA‐positive cells were increased at days 3 and 7 in the FGF7 group. Moreover, cell islands were AQP5‐positive. CONCLUSION: These results suggest that FGF7‐treated hDPSCs differentiate into AQP5‐positive and αSMA‐positive cells. Moreover, AQP5‐positive cell aggregations were formed

0.7-anomaly and magnetotransport of disordered quantum wires

The unexpected "0.7" plateau of conductance quantisation is usually observed for ballistic one-dimensional devices. In this work we study a quasi-ballistic quantum wire, for which the disorder induced backscattering reduces the conductance quantisation steps. We find that the transmission probability resonances coexist with the anomalous plateau. The studies of these resonances as a function of the in-plane magnetic field and electron density point to the presence of spin polarisation at low carrier concentrations and constitute a method for the determination of the effective g-factor suitable for disordered quantum wires.Comment: 4 pages, 6 figure