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Spontaneous dwarf rat (SDR) is a primary experimental animal model for the study of pituitary dwarfism with a point mutation in the Gh gene encoding growth hormone (GH). In previous studies, SDR has been reported to be associated with the GH deficiency as well as combined hormone deficiencies, the cause of which is unknown. In this study, we focused on the characteristics of pituitary stem/progenitor cell populations, which are a source of hormone-producing cells, in SDR. Immunofluorescence and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) analyses confirmed the defects in GH-producing cells, the decreased number of prolactin- and thyroid-stimulating hormone-producing cells, and the increased number of adrenocorticotropic hormone- and luteinizing hormone-producing cells. Additionally, qRT-PCR analysis showed increased Prop1 (an embryonic stem/progenitor cell marker) expression and decreased S100b (a putative adult stem/progenitor cell marker) expression in SDRs. In the pituitary stem/progenitor cell niche, the marginal cell layer, the proportion of SOX2/PROP1-double positive cells was higher in adult SDRs than in adult Sprague Dawley (SD) rats but that of SOX2/S100β-double positive cells was much lower. Furthermore, the number of SOX2/PROP1-double positive cells in SD rats significantly decreased with growth; however, the decrease was smaller in SDRs. In contrast, the number of SOX2/S100β-double positive cells in SD rats significantly increased with growth; however, they were few in SDRs. Thus, S100β-positive pituitary stem/progenitor cells failed to settle in pituitary dwarfism with the Gh gene mutation, leading to multiple hypopituitarism including GH deficiency.

Surfactants are functional molecules utilized in various situations. The self-assembling property of surfactants enables several molecular arrangements that can be employed to build up nanometer-sized architectures. This is beneficial in the construction of functional inorganic–organic hybrids holding the merits of both inorganic and organic components. Among several surfactants, bolaamphiphile surfactants with two hydrophilic heads are effective, as they have multiple connecting or coordinating sites in one molecule. Here, a functional polyoxotungstate inorganic anion was successfully hybridized with a bolaamphiphile to form single crystals with anisotropic one-dimensional alignment of polyoxotungstate. Keggin-type metatungstate ([H2W12O40]6−, H2W12) was employed as an inorganic anion, and 1,12-dodecamethylenediammonium (C12N2) derived from 1,12-dodecanediamine was combined as an organic counterpart. A simple and general ion-exchange reaction provided a hybrid crystal consisting of H2W12 and C12N2 (C12N2-H2W12). Single crystal X-ray structure analyses revealed a characteristic honeycomb structure in the C12N2-H2W12 hybrid crystal, which is possibly effective for the emergence of conductivity due to the dissociative protons of C12N2.

The activation of α2 adrenergic receptors contributes to analgesia not only in the central nervous system but also in the peripheral nervous system. We reported that noradrenaline inhibits the activity of transient receptor potential vanilloid 1 (TRPV1) evoked by capsaicin through α2 receptors in cultured rat dorsal root ganglion (DRG) neurons. However, it is unclear whether activation of TRPV1 expressed in peripheral nerve terminals is inhibited by α2 receptors and whether this phenomenon contributes to analgesia. Therefore, we examined effects of clonidine, an α2 receptor agonist, on several types of nociceptive behaviors, which may be caused by TRPV1 activity, and subtypes of α2 receptors expressed with TRPV1 in primary sensory neurons in rats. Capsaicin injected into hind paws evoked nociceptive behaviors and clonidine preinjected into the same site inhibited capsaicin-evoked responses. This inhibition was not observed when clonidine was injected into the contralateral hind paws. Preinjection of clonidine into the plantar surface of ipsilateral, but not contralateral, hind paws reduced the sensitivity to heat stimuli. Clonidine partially reduced formalin-evoked responses when it was preinjected into ipsilateral hind paws. The expression level of α2C receptor mRNA quantified by real-time PCR was highest followed by those of α2A and α2B receptors in DRGs. α2A and α2C receptor-like immunoreactivities were detected with TRPV1-like immunoreactivities in the same neurons. These results suggest that TRPV1 and α2 receptors are coexpressed in peripheral nerve terminals and that the functional association between these two molecules causes analgesia.

The anterior lobe (AL) of the pituitary gland consists five types of hormone-producing cells and fenestrated sinusoids (i. e., vascular endothelial cells and pericytes) that cooperate to maintain the physiological function of the gland. In addition, the population of cells located in pituitary stem/ progenitor cell niche, the marginal layer, which faces the residual lumen of the Rathke's pouch, serve to renew pituitary cells throughout life. We recently established a protocol for isolating marginal layer-derived adult pituitary stem/progenitor cells (MPSCs) by using differences in cell adhesion (1), and then showed differentiation potential into hormone-producing cells by subjecting MPSCs to three-dimensional culture. However, it is unclear whether MPSCs are capable of differentiating into all types of cells that constitute the pituitary gland. In this study, we performed DNA microarray analysis in MPSCs, which were proliferated by two-dimensional (2D) culture, for studying comprehensively gene expression profiles. Next, we investigated what kind of cells MPSCs would differentiate into. Comparing gene expression profiles of the AL and MPSCs, in MPSCs, 1776 genes were increased more than 4-fold and 1715 genes were decreased 4-fold compared to the AL (p Presentation: No date and time listed

Research on sex-determining region Y-box 2 (SOX2)-positive pituitary stem/progenitor cells, as a source of hormone-producing cells, is progressing rapidly in rodents. However, the stem/progenitor cells supplying hormone-producing cells that are essential for growth, reproduction, and lactation in bovines have not yet been identified. In this study, we characterized SOX2-positive cells in the pituitary gland of dairy cattle (Holstein heifers) after sexual maturity. Immunofluorescence analysis revealed that the localization pattern of SOX2-positive cells in the dairy cattle pituitary gland was similar to that observed in the rodent pituitary gland; the marginal cell layer (MCL), dense cell clusters, and single cells scattered in the parenchyma of the anterior lobe. Furthermore, most of the SOX2-positive cells were positive for the pituitary stem/progenitor cell niche markers E-cadherin and cytokeratin 8+18, which have been reported in rodents. In addition, in the MCL of the anterior lobe, there was a subpopulation of SOX2-positive cells positive for paired-related homeobox 1 and 2, whereas negative for S100β. Moreover, in the parenchyma of the anterior lobe, co-localization of SOX2 and pituitary hormones was infrequent. In summary, this study reveals the localization of putative pituitary stem/progenitor cells positive for SOX2 in dairy cattle. These results provide valuable information to support further investigation of cell supply in the dairy cattle pituitary gland.

A polymerizable ionic-liquid cation having methacryl group and imidazolium moieties (denoted as MAImC1) was successfully hybridized with octamolybdate (Mo8O264−, Mo8) to obtain inorganic–organic hybrid crystals containing monovalent metal cations. The hybrid crystals were initially prepared as sodium ion-containing hybrid crystal of MAImC1–Na–Mo8. The sodium cations in MAImC1–Na–Mo8 were exchangeable to other monovalent metal cations such as silver or potassium to form hybrid crystals of MAImC1–Ag–Mo8 or MAImC1–K–Mo8. Their molecular and crystal structures were clearly revealed by single crystal X-ray analyses. The MAImC1–Na–Mo8 hybrid crystal worked as the hybrid monomer, and was found polymerizable by a radical polymerization using AIBN as an initiator to obtain inorganic–organic polymers (P-MAImC1–Na–Mo8). The conductivities of the hybrid monomer and polymer consisting of MAImC1–Na–Mo8 were investigated.

Ten pairs of protrusions, called accessory lobes (ALs), exist at the lateral sides of the avian lumbosacral spinal cord. Histological evidence indicates that neuron-like cells gather in the ALs, and behavioral evidence suggests that the ALs act as a sensory organ of equilibrium during bipedal walking. Recently, using an electrophysiological method, we reported that cells showing Na+ currents and action potentials exist among cells that were dissociated from the ALs. However, it was unclear which isoforms of the voltage-gated sodium channel (VGSC) are expressed in the ALs and whether cells having neuronal morphology in the ALs express VGSCs. To elucidate these points, RT-PCR and immunohistochemical experiments were performed. In RT-PCR analysis, PCR products for Nav 1.1-1.7 were detected in the ALs. The signal intensities of the Nav 1.1 and 1.6 isoforms were stronger than those of the other isoforms. We confirmed that an antibody raised against an epitope peptide of the rat VGSC had cross-reactivity to chick tissues by Western blotting, and we performed immunofluorescence staining using the antibody. The AL contained cells having neuron-like morphology and VGSC-like immunoreactivity at their cytoplasm and/or cell membranes. Filament-like structures showing GFAP-like immunoreactivity infilled intercellular spaces. The VGSC- and GFAP-like immunoreactivities did not overlap. These results indicate that the neuronal isoforms of the VGSC are mainly expressed in the AL and that the neuron-like cells in the ALs express VGSCs. Our findings indicate that AL neurons generate action potentials and send sensory information to the motor systems on the contralateral side of the spinal segment.

Ionic liquids are an important component for constructing functional materials, and polyxometalate cluster anion is a promising partner for building inorganic&ndash, organic hybrid materials comprising ionic liquids. In such hybrid materials, the precise control of the molecular arrangement in the bulk structures is crucial for the emergence of characteristic functions, which can be realized by introducing an amphiphilic moiety into the ionic liquids. Here, an amphiphilic polymerizable imidazolium ionic liquid with a methacryloyl group was firstly hybridized with polyoxometalate anions of octamolybdate ([Mo8O26]4&minus, Mo8) and silicotungstate ([SiW12O40]4&minus, SiW12) to obtain inorganic&ndash, organic hybrid crystals. The polymerizable ionic liquid with a octyl chain (denoted as MAImC8) resulted in the formation of anisotropic molecular arrangements in the bulk crystal structure, which was compared with the hybrid crystals composed from the polymerizable ionic liquid without a long alkyl chain (denoted as MAIm). Rather densely packed isotropic molecular arrangements were observed in the hybrid crystals of MAIm&ndash, Mo8 and MAIm&ndash, SiW12 due to the lack of the amphiphilic moiety. On the other hand, using the amphiphilic MAImC8 cation gave rise to a honeycomb-like structure with the Mo8 anion and a layered structure with the SiW12 anion, respectively.

We report on highly oriented growth of VO2(B) thin films on Mo foils by reactive sputtering and its performance as an cathode electrode material in lithium ion batteries. Reactively sputtered films under moderate O2 flow and substrate temperature revealed (001)-oriented growth on the poly-crystalline Mo foils with electrically floating potential. It can be interpreted that the oriented VO2(B) film can grow on Mo substrates under narrow condition in which ions with restricted energies result in crystalline lattice formation with moderate substrate temperature. The lithium ion battery utilizing the VO2(B) film on Mo foil as cathode electrode revealed specific capacity of 110 mAhg− 1 at 2.0 V. Repeated charge/discharge experiments indicated that the oriented VO2(B) film, in which VO6 octahedra pile up with vacant cites of O atoms orderly that can act as spaces for Li intercalation and de-intercalation, has certain potential as cathode material.

Objective Nicotine, a toxic component of smoking, adversely affects animal growth and reproduction by decreasing secretion of anterior pituitary hormones. However, it has not been clarified whether nicotine inhibits the supply of endocrine cells in the pituitary gland. The present study investigated short- and long-term effects of persistent nicotine exposure on the pituitary glands of young animals. Design Three-week-old male Wistar rats were exposed to nicotine (1 mg/kg body weight/day) for 7 days, and gene expression, cell numbers, and DNA methylation status were analyzed on the following day and 4 weeks after final treatments. Results The expression level of the stem cell marker Sox2 was not changed by nicotine exposure throughout the experiment. On the other hand, nicotine inhibited expression of a progenitor cell marker, Prrx1, and growth hormone (Gh). Immunohistochemical analysis showed that the SOX2-positive cells positive for PRRX1 in nicotine-treated groups decreased to 61% (4-week-old) and 70% (8-week-old) of the saline-treated controls. In addition, the proportion of GH-positive cells in nicotine-treated group was 14% lower than that of saline-treated controls. Furthermore, first intron hypermethylation of Prrx1 was detected by a bisulfite sequence of genomic DNA from the anterior lobe of the rat pituitary gland. Conclusions We show that persistent nicotine exposure in young animals inhibits expression of Prrx1 in pituitary stem/progenitor cells through epigenetic regulation, leading to a delayed supply of GH-producing cells.

Secretion of hormones by the anterior pituitary gland can be stimulated or inhibited by paracrine factors that are produced during inflammatory reactions. The inflammation cytokine interferon-gamma (IFN-γ) is known to inhibit corticotropin-releasing factor (CRF)-stimulated adrenocorticotropin (ACTH) release but its signaling mechanism is not yet known. Using rat anterior pituitary, we previously demonstrated that the CXC chemokine ligand 10 (CXCL10), known as interferon-γ (IFN-γ) inducible protein 10 kDa, is expressed in dendritic cell-like S100β protein-positive (DC-like S100β-positive) cells and that its receptor CXCR3 is expressed in ACTH-producing cells. DC-like S100β-positive cells are a subpopulation of folliculo-stellate cells in the anterior pituitary. In the present study, we examine whether CXCL10/CXCR3 signaling between DC-like S100β-positive cells and ACTH-producing cells mediates inhibition of CRF-activated ACTH-release by IFN-γ, using a CXCR3 antagonist in the primary pituitary cell culture. We found that IFN-γ up-regulated Cxcl10 expression via JAK/STAT signaling and proopiomelanocortin (Pomc) expression, while we reconfirmed that IFN-γ inhibits CRF-stimulated ACTH-release. Next, we used a CXCR3 agonist in primary culture to analyze whether CXCL10 induces Pomc-expression and ACTH-release using a CXCR3 agonist in the primary culture. The CXCR3 agonist significantly stimulated Pomc-expression and inhibited CRF-induced ACTH-release, while ACTH-release in the absence of CRF did not change. Thus, the present study leads us to an assumption that CXCL10/CXCR3 signaling mediates inhibition of the CRF-stimulated ACTH-release by IFN-γ. Our findings bring us to an assumption that CXCL10 from DC-like S100β-positive cells acts as a local modulator of ACTH-release during inflammation.

Some non-endocrine cells in the pituitary anterior lobe are responsible for providing stem/progenitor cells to maintain hormone-producing cells. In particular, cells expressing S100β protein, a calcium-binding protein, have been hypothesized to be a pituitary cell resource. Accumulating data have revealed that S100β-positive cells comprise heterogeneous populations and some of them certainly show stem/progenitor characteristics in vivo. Hence, we examine whether S100β-positive cells have the capacity to differentiate into endocrine cells, by means of in vivo and in vitro experiments on transgenic rats expressing enhanced green fluorescent protein (EGFP) under the control of the S100β promoter. Immunohistochemistry of the pituitary confirmed that some S100β-positive cells expressed SOX2 (SRY [sex-determining region Y]-box 2) and had proliferative activity. Dispersed anterior lobe cells were observed by time-lapse microscopy, followed by immunostaining for hormone and pituitary-transcription-factor1 (PIT1). First, the dispersed anterior lobe cells were immunostained by an antibody against SOX2. S100β-protein co-localizes with SOX2 (about 89 %). Although 44 of 134 S100β-positive cells traced were proliferative but negative to any hormones, 14 cells were positive for one of the pituitary hormones and/or PIT1, confirming the presence of all types of hormone-producing cells. Notably, GFP-fluorescence appeared in two hormone-positive cells during culture. On the other hand, we observed hormone-producing cells that were not positive for S100β at the end of the time-lapse study, despite being initially positive. These findings suggest that S100β-positive cells cultured from the anterior lobe are capable of developing into hormone-producing cells, although this happens relatively infrequently.

Homeobox transcription factors are known to play crucial roles in the anterior lobe of the pituitary gland. During molecular cloning with the Yeast One-Hybrid System using a 5'-upstream region of the porcine Fshβ as a bait sequence, we have cloned a cDNA encoding a partial sequence of the retina-derived POU domain factor 1 (RPF1) from the porcine pituitary cDNA library and confirmed its specific binding to the bait sequence. In situ hybridization was performed to examine localization of Rpf1 and showed that this gene is expressed in the stem/progenitor cells of the rat pituitary primordium as well as the diencephalon and retina. In addition, real-time PCR demonstrated that Rpf1 transcripts are abundant in early embryonic periods but that this is followed by a decrease during pituitary development, indicating that this factor plays a role in differentiating cells of the pituitary. The transcriptional activity of RPF1 for genes of Prop1, Prrx1 and Prrx2, which were characterized as genes participating in the pituitary stem/progenitor cells by our group, was then examined with full-length cDNA obtained from the rat pituitary. RPF1 showed regulatory activity for Prop1 and Prrx2, but not for Prrx1. These results indicate the involvement of this retina-derived factor in pituitary development.

S100β-protein-positive cells in the anterior pituitary gland appear to possess multifunctional properties. Because of their pleiotropic features, S100β-positive cells are assumed to be of a heterogeneous or even a non-pituitary origin. The observation of various markers has allowed these cells to be classified into populations such as stem/progenitor cells, epithelial cells, astrocytes and dendritic cells. The isolation and characterization of each heterogeneous population is a prerequisite for clarifying the functional character and origin of the cells. We attempt to isolate two of the subpopulations of S100β-positive cells from the anterior lobe. First, from transgenic rats that express green fluorescent protein (GFP) driven by the S100β protein promoter, we fractionate GFP-positive cells with a cell sorter and culture them so that they can interact with laminin, a component of the extracellular matrix. We observe that one morphological type of GFP-positive cells possesses extended cytoplasmic processes and shows high adhesiveness to laminin (process type), whereas the other is round in shape and exhibits low adherence to laminin (round type). We successfully isolate cells of the round type from the cultured GFP-positive cells by taking advantage of their low affinity to laminin and then measure mRNA levels of the two cell types by real-time polymerase chain reaction. The resultant data show that the process type expresses vimentin (mesenchymal cell marker) and glial fibrillary acidic protein (astrocyte marker). The round type expresses dendritic cell markers, CD11b and interleukin-6. Thus, we found a method for isolating dendritic-cell-like S100β-positive cells by means of their property of adhering to laminin.

Paired-related transcription factors, PRRX1 and PRRX2, which are present in mesenchymal tissues and participate in mesenchymal cell differentiation, were recently found in the stem/progenitor cells of the pituitary gland of ectodermal origin. To clarify the role of PRRX1 and PRRX2 in the pituitary gland, the present study first aimed to identify transcription factors that regulate Prrx1 and Prrx2 expression. A promoter assay for the upstream regions of both genes was performed by co-transfection of the expression vector of several transcription factors, many of which are frequently found in the pituitary stem/progenitor cells. The results for the promoter activity of both genes showed expression in a cell type-dependent manner. Comprehensive comparison of transcriptional activity of several transcription factors was performed with CHO cells, which do not show Prrx1 and Prrx2 expression, and the results revealed the presence of common and distinct factors for both genes. Among them, KLF6 showed specific and remarkable stimulation of Prrx2 expression. In vitro experiments using an electrophoretic mobility shift assay and siRNA interference revealed a potential ability for regulation of Prrx2 expression by KLF6. Finally, immunohistochemistry confirmed the presence of KLF6 in the SOX2/PRRX2 double-positive stem/progenitor cells of the postnatal pituitary gland. Thus, the finding of KLF6 might provide a novel clue to clarify the maintenance of stem/progenitor cells of the postnatal pituitary gland.

We recently reported that the quantitative and qualitative transition of stem/progenitor cells occurs by the acquisition of a novel mechanism in the terminal differentiation during postnatal development of the anterior pituitary. We hypothesised that this novel mechanism is an alteration of a cell supply system accompanying proliferation of the progenitor cells. In the present study, we examined the proliferation activities of progenitor cells by indication of the expression of Nestin, a marker of rapidly dividing progenitor cells, aiming to verify our hypothesis and to resolve another outstanding issue regarding whether the Nestin gene is expressed in the pituitary. We found that NESTIN-positive dividing cells certainly exist in the pituitary through all stages of development. Almost all of the PROP1-positive progenitor cells express Nestin in early embryonic pituitary development. Thereafter, Nestin-expressing dividing cells involved in the cell supply system transfer from PROP1-positive progenitor cells to committed progenitor cells, such as PIT1-positive cells, on neonatal pituitary development. Furthermore, our data, together with the findings of previous studies on cell lineage tracing analyses using Nestin-Cre mice derived by the central nervous system (CNS)-specific Nestin promoter, suggest that at least two regulation systems for Nestin-expression exist in the pituitary, with the majority of these not being CNS-specific.

Lithium nickel manganese oxide, LiNi0.5Mn1.5O4, a cathode material for lithium-ion batteries was synthesized by a microwave heating method. Synthesized samples were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical properties. The results revealed that spinel LiNi0.5Mn1.5O4 powders can be directly synthesized by microwave heating. The precursor prepared using 48 to 64 g of PVA solution would be best to synthesize LiNi0.5Mn1.5O4 successfully by microwave heating.

Paired-related homeobox transcription factors, PRX1 and PRX2, are verified to play essential roles in limb, heart and craniofacial development by analyses of knockout animals. Their gene expression in the embryonic primordia derived from the mesoderm and neural crest is confirmed by in situ hybridization. Nevertheless, a detailed localization of PRX1 and PRX2 was not carried out because of a lack of specific antibodies for each factor. We have previously confirmed the presence of PRX proteins in rat embryonic pituitary by using an antibody that recognizes both PRX1 and PRX2. However, the pituitary originates in the cranial placodes, not the mesoderm or neural crest. In this study, we analyze the temporospatial distribution of PRX1 and PRX2 with novel antibodies specific for each factor, together with a stem/progenitor marker SOX2 (sex-determining region Y-box 2) in the primordia formed by epithelio-mesenchymal interaction. We observe immunoreactive signals of both PRX proteins in rat embryo, showing a similar pattern to that obtained by in situ hybridization. In early embryogenesis, PRX proteins are not co-localized with SOX2 but PRX2 and/or PRX1-positive cells are present in the border or periphery of SOX2-positive primordia originating in the cranial placode. During advanced embryogenesis, either PRX2-positive cells become condensed in the border of SOX2-positive cells or PRX1 and/or PRX2 become co-localized with SOX2. Our results suggest that PRX proteins, especially PRX2, play a role in the morphogenesis of the primordial tissues formed by the epithelio-mesenchymal interaction and that neural crest cells contribute to the morphogenesis of tissues derived from the cranial placode.

Recently we demonstrated an ectopic expression of the human herpesvirus 1 thymidine kinase (HHV1-TK) gene by functioning of an intrinsic endogenous promoter in the transgenic rat (TG-rat), suggesting that HHV1 infection in humans induces expression of the TK gene with the ectopic promoter in the testis and results in accumulation of HHV1-TK protein, triggering male infertility similar to that in the TG-rat. Hence, in this study, we started to investigate a relationship between infection of herpesvirus and human male infertility. Semen was donated by Chinese male infertile patients (153 men, aged 21–49 years) with informed consent, followed by DNA preparation and analysis by PCR and DNA sequencing. Semen volume, sperm number and density, and sperm motility were examined. DNAs of HHV1, HHV4, HHV5 and HHV6 were confirmed by PCR, electrophoresis and DNA sequencing. Finally, virus DNA was identified in 59 patients (39%). The number of carriers was 39 (25%) for HHV1, 6 (4%) for HHV4, 33 (22%) for HHV5 and 3 (2%) for HHV6, respectively. Moreover, double-infection was found in 22 out of 59 specimens (37%), most of which were double-infection of HHV1 and HHV5 (15 out of 22 carriers). Though slight severity was present in some of the carriers, the relationship between virus infection and sperm impairment was not conclusive. Accordingly, it is essential to examine whether the viral HHV1-TK gene is expressed in the testis of the infertile human HHV carrier.

The adenohypophysis comprises six types of endocrine cells, including PIT1-lineage cells such as growth hormone (GH)-producing cells and heterogeneous non-endocrine cells, such as pituitary stem/progenitor cells as a source of endocrine cells. We determine the expression of characteristic stem cell marker genes, including sex-determining region Y-box 2 (Sox2), in mouse pituitary-derived non-endocrine cell lines Tpit/E, Tpit/F1 and TtT/GF. We observed high expression of fibroblast growth factor (FGF) receptors in Tpit/F1 cells, which we characterised by cultivation in medium containing a basic FGF and B27 supplement as used for neural stem-cell differentiation. A 4-day cultivation of Tpit/F1 produced floating embryonic stem-cell-like clumps accompanied by a three-fold increase in Sox2 expression. Passages in these clumps maintained the proliferative activity and Sox2 expression levels. After 10 days of cultivation, Tpit/F1 cell clumps were immuno-positive for SOX2 and Ki67 (proliferation marker) and loosely attached to the well bottom. An additional 10 days of cultivation induced the emergence of GH-positive/pituitary-specific transcription factor (PIT1)-negative cells showing migration from the clumps. Pit1 overexpression in attached cells could not induce GH production. Finally, we confirmed the presence of PIT1-negative GH-producing cells (3.2-7.7 % of all GH-positive cells) in rat pituitary. Thus, we demonstrate that Tpit/F1 has the plasticity to differentiate into one type of hormone-producing cell.

We recently cloned a paired-related homeodomain protein Prx2 as a novel factor in the pituitary. In the present study, we investigated the ontogenic profiles of Prx2 and another cognate Prx1 in the rat embryonic pituitary. Quantitative real-time polymerase chain reaction showed low expression of Prx2 and a marked increase of Prx1 on rat embryonic day (E)20.5. Immunohistochemical analyses using an antibody that recognises both proteins, with the aim of investigating their roles in pituitary organogenesis, demonstrated that PRXs first appear in the Rathke's pouch on E13.5 in the pituitary stem/progenitor cells expressing Prop1 and Sox2. After E16.5, the number of Prx-expressing cells was increased in both anterior and intermediate lobes. SOX2(+) stem/progenitor cells in the intermediate lobe started to produce PRXs, and PRX(+) /SOX2(+) /PROP1(+) -cells were present on the anterior side of the marginal cell layer and were scattered in the parenchyma of the anterior lobe. On the other hand, PRX(+) -cells negative for PROP1 and SOX2 were located in the anterior lobe. Analysis of the relationship with pituitary endocrine cells revealed that a part of PRX(+) /PROP1(-) /SOX2(-) -cells in the anterior lobe co-expressed all types of hormones. The proportion of co-localisation of PRXs and hormones was highest on the day each hormone first appeared. These data indicate that PRXs are produced in the pituitary progenitor cells and may play roles in the process of terminal differentiation during early pituitary organogenesis. An in vitro small interfering RNA-knockdown experiment in the pituitary-derived cell line, TtT/GF, revealed that PRX1 and PRX2 play roles in proliferation by different mechanisms because knockdown of Prx2, but not Prx1, induced the p21 expression. Furthermore, immunohistochemical analysis demonstrated that 76% of PRXs(+) cells were positive for a cell proliferation marker Ki67 in the E18.5 pituitary. This is the first report of the involvement of PRX1 and PRX2 in organogenesis of tissue originating from the ectoderm other than the mesoderm.

The synthesis of Ba1-xSrxTiO3(BST) powders was attempted using KOH-KNO3 molten salt. The starting materials, Ba(NO3)2, Sr(NO3)2 ,TiO2,and the mixed salt of KOH-KNO3, were well-mixed. The mixture was heated at 300 to 500°C for 1 hour, and the product was thoroughly washed with de- ionized hot water. When the mixture containing excess TiO2 was used, single-phase BST powders with a particle size of 10~50nm were obtained.

Diquat toxicity causes iron-mediated oxidative stress; however, it remains unclear how diquat affects iron metabolism. Here, we examined the effect of diquat-induced oxidative stress on iron metabolism in male Fischer-344 rats, with particular focus on gene expression. Hepatic nonheme iron content was unchanged until 20 h after diquat treatment. Hepatic free iron levels increased markedly in the early stages following treatment and remained elevated for at least 6 h, resulting in severe hepatotoxicity, until returning to control levels at 20 h. The level of hepatic ferritin, especially the H-subunit, increased 20 h after diquat treatment due to elevated hepatic ferritin-H mRNA expression. These results indicate that early elevated levels of free iron in the liver of diquat-treated rats cause hepatotoxicity, and that this free iron is subsequently sequestered by ferritin synthesized under conditions of oxidative stress, thus limiting the pro-oxidant challenge of iron. The plasma iron concentration decreased at 6 and 20 h after diquat treatment, whereas the level of plasma interleukin-6 increased markedly at 3 h and remained high until 20 h. In the liver of diquat-treated rats, expression of hepcidin mRNA was markedly upregulated at 3 and 6 h, whereas ferroportin mRNA expression was downregulated slightly at 20 h. Transferrin receptor 1 mRNA expression was significantly upregulated at 3, 6, and 20 h. These results indicate that inhibition of iron release from iron-storage tissues, through stimulation of the interleukin-6-hepcidin-ferroportin axis, and enhanced iron uptake into hepatocytes, mediated by transferrin receptor 1, cause hypoferremia.

Cathode materials for a lithium-ion battery were prepared using an industrial microwave furnace. The prepared materials were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical properties. Single-phase LiMn2O4 powders could be prepared in a few minutes using an industrial microwave furnace. The obtained results showed that this microwave heating method is a promising industrial technique for efficient preparation of cathode materials.

Barium strontium titanate (BST), which has a typical perovskite-type structure, shows excellent electrical properties. BST powders were synthesized by heating mixtures of commercial reagents with an excess of TiO2 in molten salts of KOH and KNO3, and the sintering behavior of the resulting powders was evaluated. The sample with the highest density of 95% was obtained by sintering of the BST powders.

The synthesis of Ba0.5Sr0.5TiO3 (BST) powders was attempted using KOH-KNO3 molten salt. Single-phase BST powders could not be obtained when stoichiometric powders were regardless of the molten salt composition. Only when powders with excessive TiO2 were used, single-phase BST powders were obtained. The shape and aggregation state of the single-phase BST powder changed according to the heating temperature and the molten salt composition.

TiO2-based ceramic humidity sensors containing small amounts of Li2O and V2O5 were prepared by a solid-reaction method. The relationship between the pore structures of the sensors and one of the most important humidity properties, hysteresis in humidity sensitivity, was studied. The humidity sensitivity was investigated by measuring the impedance of the sensors under various conditions of humidity, and the pore-size distribution was measured by mercury-intrusion porosimetry and by the nitrogen-adsorption method. The hysteresis property of the sensors was shown to be significantly dependent on their microstructure, particularly the volume ratio of mesopores to all pores in the sensor elements. Nitrogen adsorption was found to be more useful than mercury porosimetry for determining the proportion of mesopores in the samples.

Dense ceramics of potassium tantalate niobates (KTa 1− X Nb X O 3 : X = 0.4) with a perovskite-type structure were prepared using powders including excess K 2 O and surrounding powder, and by applying vibration to the surrounding powder prior to firing. Excess K 2 O was inevitable for increasing density, and the use of surrounding powder reduced density fluctuation to a considerable extent. Furthermore, the powder including 8 mol% excess K 2 O fired at 1150 °C led to dense ceramics with relative density higher than 90%. The chemical composition of the resulting dense ceramics prepared here was confirmed to be that of a desired perovskite, KTa 0.6 Nb 0.4 O 3 . The KTa 1− X Nb X O 3 ceramics obtained here showed almost the same dielectric properties as those prepared by delicate, costly, and time-consuming methods.

After injection with 0.1 mmol diquat/kg body weight, survival time was markedly shorter in Fischer-344 rats fed a purified diet than in rats fed a regular diet, and much more severe hepatotoxicity and nephrotoxicity were observed in the former than in the latter. The longer the feeding period on the purified diet, the shorter the survival time after diquat administration. These results indicate that the purified diet lacked components present in the regular diet that had protective effects against diquat toxicity. These two diets had nearly the same composition and content of vitamins and minerals. We tested the ingredients of the regular diet to determine which ones reduce diquat toxicity. We found that wheat bran had a protective effect, but that rice bran and bean-curd refuse (okara) did not.

Pituitary-specific transcription factor PROP1, a factor important for pituitary organogenesis, appears on rat embryonic day 11.5 (E11.5) in SOX2-expressing stem/progenitor cells and always coexists with SOX2 throughout life. PROP1-positive cells at one point occupy all cells in Rathke's pouch, followed by a rapid decrease in their number. Their regulatory factors, except for RBP-J, have not yet been clarified. This study aimed to use the 3 kb upstream region and 1st intron of mouse prop1 to pinpoint a group of factors selected on the basis of expression in the early pituitary gland for expression of Prop1. Reporter assays for SOX2 and RBP-J showed that the stem/progenitor marker SOX2 has cell type-dependent inhibitory and activating functions through the proximal and distal upstream regions of Prop1, respectively, while RBP-J had small regulatory activity in some cell lines. Reporter assays for another 39 factors using the 3 kb upstream regions in CHO cells ultimately revealed that 8 factors, MSX2, PAX6, PIT1, PITX1, PITX2, RPF1, SOX8 and SOX11, but not RBP-J, regulate Prop1 expression. Furthermore, a synergy effect with SOX2 was observed for an additional 10 factors, FOXJ1, HES1, HEY1, HEY2, KLF6, MSX1, RUNX1, TEAD2, YBX2 and ZFP36Ll, which did not show substantial independent action. Thus, we demonstrated 19 candidates, including SOX2, to be regulatory factors of Prop1 expression.

The pituitary gland, an indispensable endocrine organ that synthesizes and secretes pituitary hormones, develops with the support of many factors. Among them, neuronatin (NNAT), which was discovered in the neonatal mouse brain as a factor involved in neural development, has subsequently been revealed to be coded by an abundantly expressing gene in the pituitary gland but its role remains elusive. We analyze the expression profile of Nnat and the localization of its product during rat pituitary development. The level of Nnat expression was high during the embryonic period but remarkably decreased after birth. Immunohistochemistry demonstrated that NNAT appeared in the SOX2-positive stem/progenitor cells in the developing pituitary primordium on rat embryonic day 11.5 (E11.5) and later in the majority of SOX2/PROP1 double-positive cells on E13.5. Thereafter, during pituitary embryonic development, Nnat expression was observed in some stem/progenitor cells, proliferating cells and terminally differentiating cells. In postnatal pituitaries, NNAT-positive cells decreased in number, with most coexpressing Sox2 or Pit1, suggesting a similar role for NNAT to that during the embryonic period. NNAT was widely localized in mitochondria, peroxisomes and lysosomes, in addition to the endoplasmic reticulum but not in the Golgi. The present study thus demonstrated the variability in expression of NNAT-positive cells in rat embryonic and postnatal pituitaries and the intracellular localization of NNAT. Further investigations to obtain functional evidence for NNAT are a prerequisite.

LiFePO4 powders were prepared by a citric acid complex method. The effects of source composition and firing conditions on the formation of LiFePO4 were investigated. Single phase and well-crystallized LiFePO4 powders were obtained at 500°C for 5h. The particle size of the obtained powder is smaller than that of powder prepared by the conventional solid-state reaction method.

Viscosity, conductivity, pH and concentration of silicic acid in a solution of tetraethylorthosilicate (TEOS)-cetyltrimethylammonium bromide (CTAB)-water (H2O)-nitric acid (HNO3) system have been measured, and the formation process of a precursor solution for preparing transparent mesoporous silica thin films was postulated. For the precursor solution of TEOS/CTAB/H2O=8/1/185 molar ratio, the relationship of viscosity vs. concentration of silica in a solution at aging times of 15 to 23 h showed good linearity with a slope which became steeper with time, while the viscosity of silica remained almost unchanged for aging times of 3 to 11 h. These results showed that the initial stage includes spherical polysilicate and the later stage a linear one. The concentration of silicic acid in precursor solutions showed the maximum at the aging time of about 1.6 h. The conductivity in the precursor solution of TEOS/CTAB/H2O=8/1/185 molar ratio was measured, and it slowly decreased with slight fluctuation, exhibiting a the maximum value at the aging time of about 2.5 h. This type of conductivity change suggested that silicic acid or polysilicate interacts with CTAB. The pH of the precursor solution remained unchanged at around 3 throughout the measurement. From these results, the formation process of a precursor solution was assumed as follows; 1st step: cationization of +H3O•Si(OH)3; 2nd step: complexation of silicic acid cation and CTAB micell; 3rd step: polymerization of silicic acid on CTAB micell; 4th step: separation of CTAB and polysilicate; 5th step: adsorption of CTAB on polysilicate; 6th step: complexation of CTAB and polysilicate; 7th step: formation of hexagonal structure.

The surface excess amounts of supercritical carbon dioxide (SC-CO 2 ) on NaY-type zeolite were measured by an isochoric method at 308.2 K. The adsorption amounts of 2,6- and 2,7-dimethylnaphthalene (DMN) isomers dissolved in SC-CO 2 were also measured at 308.2 K by an isochoric method with an ultraviolet detector. The surface excess amounts of CO 2 show a maximum value near the critical pressure of CO 2 and then markedly decrease with increasing pressure and eventually become constant at high pressure. The adsorption amounts of 2,6- and 2,7-DMN gradually decrease with increasing total pressure. The adsorption amounts of 2,7-DMN are about six times higher than those of 2,6-DMN. The separation coefficients in supercritical CO 2 are much higher than those in liquid octane and ethanol. The experimental data were correlated by an extended Radke-Prausnitz equation. The correlated results are in good agreement with the experimental data.

We report on a novel synthetic method of microwave processing with a domestic microwave oven to prepare LiFePO 4 cathode materials. We also studied and report on the electrochemical properties of the resultant products. XRD revealed that a single phase LiFePO 4 powder can be synthesized quickly and easily by microwave processing. The initial discharge capacity of a cell assembled with the powder was 125 mAh/g at 60 °C. The LiFePO 4 obtained has a high electrochemical capacity and good cycle ability. These results indicate that microwave processing is a promising method for preparing LiFePO 4 cathode materials.

Formation mechanism of spherical mesoporous silica particles prepared using dodecylamine (DDA) as a template was investigated by measuring surface tension, conductivity, pH and concentration of silicic acid in the mixed solutions. Porous structure of spherical mesoporous silica was found for irregular structure by means of X-ray diffraction and scanning electron microscopy. The fomation of DDA micell in DDA-H2O-C2H5OH system was confirmed by the presence of inflection points for tension and conductivity curves at about 0.5 mmol/l of DDA concentration. When tetraethyl orthsilicate was added in the solution, the conductivity raised suddenly, stayed the same for a few minutes, and decreased steadily while the concentration of silicic acid decreased largely. In addition, the value of pH shifted from about 11 to 9.8 at the same time. From these results, the formation mechanism of spherical mesoporous silica is considered to be as follows; 1st step: cationization(DDAH+) of DDA; 2nd step: formation of DDA H+ micell; 3rd step: hydrolysis of TEOS and polymerization of silicic acid; 4th step: complexation of DDAH+ and polysilicic acid; 5th step: nucleation and growth of the mesoporous silica; and 6th step: reconfiguration and growth of the mesoporous silica particles.

Transparent mesoporous silica thin films were successfully fabricated via spin coating method using precursor solutions of water/tetraethyl orthosilicate (TEOS) system with cetyltrimethylammonium bromide (CTAB) and nitric acid catalysis. The optimum conditions for the fabrication of films were as follows: 1) The molar ratios of precursor solution were TEOS/CTAB/H2O=3-9.5/1/185 in the pH range 2-3 adjusted by nitric acid. The precursor solution became transparent after aging for 2-3 h, and transparent thin films were obtained by spinning at 1000-5000 rpm. 2) The thickness of transparent thin films obtained by a single spincoating was 0.5-1.2 μm. The transmittance to visible light and the refractive index of thin films were measured to be 97% and 1.44, while Vickers hardness and Young’s modulus were 0.706 GPa and 32.2 GPa, respectively. The transparency of thin films was unchanged after drying at 373 K or firing at 723 K. 3) The characteristic diffraction peak of mesoporous structure at 2θ=2-3° in X-ray diffraction (XRD) diagrams was observed for all transparent thin films. The crystal phase of these films varied from lamella, hexagonal to cubic when compositions of TEOS/CTAB in precursor solutions were increased from 3-7, 7.5-8 to 9-9.5.