NR5A1 is required for functional maturation of Sertoli cells during postnatal development

The orphan nuclear receptor steroidogenic factor 1 (NR5A1 (SF-1)) is expressed in both Sertoli and Leydig cells in the testes. This study investigates the postnatal development of the testes of a gonad-specific Nr5a1 knockout (KO) mouse, in which Nr5a1 was specifically inactivated. The KO testes appeared histologically normal from postnatal day 0 (P0) until P7. However, disorganized germ cells, vacuoles, and giant cells appeared by P14 in the seminiferous tubules of KO but not control mice. Expression of NR5A1 and various factors was examined by immunohistochemistry (IHC). The number of NR5A1-positive Sertoli cells in the KO testes was lower compared with controls at all the developmental stages and decreased to nearly undetectable levels by P21. IHC for anti-Müllerian hormone and p27, immature and mature Sertoli cell markers, respectively, indicated a delay in Sertoli cell maturation in the KO testes. The number of Sertoli cell-expressing factors involved in Sertoli cell differentiation including WT1, SOX9, GATA4, and androgen receptor were lower in the KO testes compared with controls. Furthermore, fewer proliferating cell nuclear antigen-positive proliferative germ cells were observed, and the number of TUNEL-labeled cells was significantly higher in the KO testes compared with controls at P14 and P21, indicating impaired spermatogenesis. IHC for CYP11A1 (SCC) indicated the presence of steroidogenic Leydig cells in the interstitium of the KO testes at all stages examined. These results suggest that NR5A1 is essential for Sertoli cell maturation and therefore spermatogenesis, during postnatal testis development.     

Prenatal Exposure to Polycyclic Aromatic Hydrocarbons and Birth Outcomes

The effect of prenatal exposure to polycyclic aromatic hydrocarbons (PAHs) at the environmental level on birth size was examined. The concentration of 1-hydroxypyrene (1-OHP) in spot urine samples collected from 50 pregnant women in Tokyo was measured and was related to birth weight, length, and head circumference of the newborns the subjects delivered. Analysis of inter- and intra-individual variation in 1-OHP concentration in spot urine samples from non-smoking subjects revealed that single spot urine can represent the subject's exposure to PAHs over several weeks and utility of spot urine for assessing PAHs exposure level of non-smokers was indicated. Geometric mean urinary concentration of 1-OHP of the subjects was 0.056 μmol/mol creatinine, and smoking mothers (n = 7) excreted more 1-OHP (0.200 μmol/mol-cre) than non-smoking mothers (0.046 μmol/mol-cre). Multiple regression analysis using birth outcomes as the dependent variable and urinary 1-OHP and other covariates as independent variables revealed that urinary 1-OHP was not a significant variable to explain birth outcomes among non-smoking mothers.     

Experimental study of culture for mouse fibroblast used conductive polymer films

The purpose of this study is to develop electrodes for electrical stimulation of the nervous system using conductive polymers, polypyrrole (PPy) and/or poly(3,4-ethylenedioxythiophene), PEDOT. We evaluated biocompatibility in fibroblast and/or myoblast of mouse. Cultured cells on PPy and/or PEDOT extended their neuritis and survived over a week. These experiments have demonstrated that conductive polymers such as PPy, PEDOT, etc. have high biocompatibility, and PPy and/or PEDOT are applicable to nerve stimulation electrodes.     

Crossover from spin-flop coupling to collinear spin alignment in antiferromagnetic/ferromagnetic nanostructures

The technologically important exchange coupling in antiferromagnetic/ferromagnetic bilayers is investigated for embedded nanostructures defined in a LaFeO(3)/La(0.7)Sr(0.3)MnO(3) bilayer. Exploiting the element specificity of soft X-ray spectromicroscopy, we selectively probe the magnetic order in the two layers. A transition from perpendicular to parallel spin alignment is observed for these nanostructures, dependent on size and crystalline orientation. The results show that shape-induced anisotropy in the antiferromagnet can override the interface exchange coupling in spin-flop coupled nanostructures.     

Preparation and characterization of nanoscale aromatic polyamide particles

Aromatic polyamide particles were prepared by reacting m-phthalyl chloride and 4,4′-diaminodiphenyl ether in a dioxane solution with high water content using a precipitation polymerization method. These nanoscale particles were spherical with a narrow size distribution. The morphologies and characteristic features of the polyamide products obtained depended strongly on the water content of this polymerization system. The characteristic features of the polyamide products were correlated with the amount of HCl (generated during polycondensation) complexed with polyamide products. Water was essential for the formation of spherical particles and played an important role in determining the polarity of the reaction solution. Further, water removed HCl from this condensation reaction system and played an important role as a reaction accelerator.     

Annihilating ideals for an algebraic local cohomology class

Hypersurface isolated singularities are considered in the context of algebraic analysis. A method for computing relative ?ech cohomology representations of algebraic local cohomology classes supported at the isolated singular point is described. An effective method to test membership and a method to compute the normal form for the Jacobi ideal are presented. The main purpose of this paper is to provide an effective algorithm for computing annihilating ideals, in the ring of partial differential operators, of the algebraic local cohomology class that generates the dual vector space to the local Milnor algebra.     

Central Nervous System Stimulants Limit Caffeine Transport at the Blood–Cerebrospinal Fluid Barrier

Caffeine, a common ingredient in energy drinks, crosses the blood–brain barrier easily, but the kinetics of caffeine across the blood–cerebrospinal fluid barrier (BCSFB) has not been investigated. Therefore, 127 autopsy cases (Group A, 30 patients, stimulant-detected group; and Group B, 97 patients, no stimulant detected group) were examined. In addition, a BCSFB model was constructed using human vascular endothelial cells and human choroid plexus epithelial cells separated by a filter, and the kinetics of caffeine in the BCSFB and the effects of 4-aminopyridine (4-AP), a neuroexcitatory agent, were studied. Caffeine concentrations in right heart blood (Rs) and cerebrospinal fluid (CSF) were compared in the autopsy cases: caffeine concentrations were higher in Rs than CSF in Group A compared to Group B. In the BCSFB model, caffeine and 4-AP were added to the upper layer, and the concentration in the lower layer of choroid plexus epithelial cells was measured. The CSF caffeine concentration was suppressed, depending on the 4-AP concentration. Histomorphological examination suggested that choroid plexus epithelial cells were involved in inhibiting the efflux of caffeine to the CSF. Thus, the simultaneous presence of stimulants and caffeine inhibits caffeine transfer across the BCSFB.     

Effects of micafungin on the morphology of Aspergillus fumigatus

The morphological effects of micafungin, a member of a new class of antifungal agents candins, on growing hyphae of Aspergillus fumigatus were studied by the use of Nomarski microscopy, scanning electron microscopy and thin-section electron microscopy. Micafungin at concentrations of 0.001-0.1 microg ml(-1) strongly inhibited the in vitro growth of this fungus and induced striking changes in the hyphal morphology, depending on the drug concentration and the length of the incubation period. The changes observed included increased formation of branches on the lateral walls, disruption of the tips of both hyphal cells and branches, and crushing and collapse of whole hyphae. In addition, micafungin was also effective in damaging membranous structures, including disruption of the cell membrane, partial loss of nuclear membranes and expansion of endoplasmic reticula. From these results, it was concluded that micafungin primarily affected the normal formation of cell walls and septa of growing hyphae. The inhibition of apical growth of hyphae accompanied by excessive lateral branching that was followed by disruption of both hyphal tips and branch tips ultimately led to the destruction of whole hyphae. This cytological effect of micafungin on the hyphal growth of A. fumigatus can explain its potent anti-Aspergillus activity.     

Nondestructive Quality Assurance of Ceramic Filters Using Noncontact Dynamic Characterization

Ceramic candle filters are stiff cylindrical structures arranged in rosettes in a hot gas vessel. Custom-made with strong composite materials, these filters are designed to withstand heating and cooling cycles of very high temperature gradients during coal energy production processes. To ensure consistency in the manufactured filters, noncontact dynamic characterization using laser vibrometry is proposed as a factory quality control technique. To evaluate the proposed technique, a sensitivity study using both contact and noncontact vibration measurements is first conducted. The shift in natural vibration frequencies is used as a quality indicator for likely manufacturing variables. Six candle filters are tested using dynamic impact tests. Contact and noncontact results are compared with theoretical natural frequency values, which show that laser results were “noisier” due to dropout from speckle noises. The results are used to establish the sensitivity of the technique, which indicates that dynamic characterization is a valid nondestructive testing technique for quality assurance of the ceramic filters, provided that the manufactured filters have a quality variation greater than 3.21%.