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Intestinal Tuft cells sense luminal contents to influence the mucosal immune response against eukaryotic infection. Paneth cells secrete antimicrobial proteins as part of the mucosal protective barrier. Defects in Tuft and Paneth cells occur commonly in various gut mucosal disorders. MicroRNA-195 (miR-195) regulates the stability and translation of target mRNAs and is involved in many aspects of cell processes and pathologies. Here, we reported the posttranscriptional mechanisms by which miR-195 regulates Tuft and Paneth cell function in the small intestinal epithelium. Mucosal tissues from intestinal epithelial tissue-specific miR-195 transgenic (miR195-Tg) mice had reduced numbers of double cortin-like kinase 1 (DCLK1)-positive (Tuft) and lysozyme-positive (Paneth) cells, compared with tissues from control mice, but there were no effects on Goblet cells and enterocytes. Intestinal organoids expressing higher miR-195 levels from miR195-Tg mice also exhibited fewer Tuft and Paneth cells. Transgenic expression of miR-195 in mice failed to alter growth of the small intestinal mucosa but increased vulnerability of the gut barrier in response to lipopolysaccharide (LPS). Studies aimed at investigating the mechanism underlying regulation of Tuft cells revealed that miR-195 directly interacted with the Dclk1 mRNA via its 3′-untranslated region and inhibited DCLK1 translation. Interestingly, the RNA-binding protein HuR competed with miR-195 for binding Dclk1 mRNA and increased DCLK1 expression. These results indicate that miR-195 suppresses the function of Tuft and Paneth cells in the small intestinal epithelium and further demonstrate that increased miR-195 disrupts Tuft cell function by inhibiting DCLK1 translation via interaction with HuR.

Background & Aims The protective intestinal mucosal barrier consists of multiple elements including mucus and epithelial layers and immune defense; nonetheless, barrier dysfunction is common in various disorders. The imprinted and developmentally regulated long noncoding RNA H19 is involved in many cell processes and diseases. Here, we investigated the role of H19 in regulating Paneth and goblet cells and autophagy, and its impact on intestinal barrier dysfunction induced by septic stress. Methods Studies were conducted in H19-deficient (H19-/-) mice, mucosal tissues from patients with sepsis, primary enterocytes, and Caco-2 cells. Septic stress was induced by cecal ligation and puncture (CLP), and gut permeability was detected by tracer fluorescein isothiocyanate–dextran assays. The function of Paneth and goblet cells was examined by immunostaining for lysozyme and mucin 2, respectively, and autophagy was examined by microtubule-associated proteins 1A/1B light chain 3 II immunostaining and Western blot analysis. Intestinal organoids were isolated from H19-/- and control littermate mice and treated with lipopolysaccharide (LPS). Results Intestinal mucosal tissues in mice 24 hours after exposure to CLP and in patients with sepsis showed high H19 levels, associated with intestinal barrier dysfunction. Targeted deletion of the H19 gene in mice enhanced the function of Paneth and goblet cells and promoted autophagy in the small intestinal mucosa. Knockout of H19 protected Paneth and goblet cells against septic stress, preserved autophagy activation, and promoted gut barrier function after exposure to CLP. Compared with organoids from control littermate mice, intestinal organoids isolated from H19-/- mice had increased numbers of lysozyme- and mucin 2–positive cells and showed increased tolerance to LPS. Conversely, ectopic overexpression of H19 in cultured intestinal epithelial cells prevented rapamycin-induced autophagy and abolished the rapamycin-induced protection of the epithelial barrier against LPS. Conclusions In investigations of mice, human tissues, primary organoids, and intestinal epithelial cells, we found that increased H19 inhibited the function of Paneth and goblet cells and suppressed autophagy, thus potentially contributing to barrier dysfunction in intestinal pathologies., Graphical abstract

This work is concerned with the kinetics of laser-induced reductive sintering of nonstoichiometric crystalline nickel oxide (NiO) nanoparticles (NPs) under ambient conditions. The mechanism of photophysical reductive sintering upon irradiation using a 514.5 nm continuous-wave (CW) laser on NiO NP thin films has been studied through modulating the laser power density and illumination time. Protons produced due to high-temperature decomposition of the solvent present in the NiO NP ink, oxygen vacancies in the NiO NPs, and electronic excitation in the NiO NPs by laser irradiation all affect the early stage of the reductive sintering process. Once NiO NPs are reduced by laser irradiation to Ni, they begin to coalesce, forming a conducting material. In situ optical and electrical measurements during the reductive sintering process take advantage of the distinct differences between the oxide and the metallic phases to monitor the transient evolution of the process. We observe four regimes: oxidation, reduction,...

The purposes of this study are to investigate the description of scientifically debatable carbonic acid in the Korean high school textbooks, characterize the physical properties of ‘carbonic acid solutions’ by using an MBL set-up and compare the properties with textual ones. Four different aqueous solutions of carbon dioxide have been prepared and analyzed: naturally aerated aqueous solution, dry ice-dissolving solution, CO 2 -bubbling solution and commercial carbonic acid water. Experimental findings showed that pH and conductivity of these 4 solutions ranged from 3.85 to 5.66 and from 0.21 µS/cm to 272.1 µS/cm, respectively. Out of these solutions, the dissociation constant( K a1 ) of the bubbling solution at room temperature couldbe calculated to 5.7 × 10 -7 which value is comparable to the textual 4.3 × 10 -7 within experimental errors, which means that textualcompound is not pure carbonic acid but the equilibrated mixture of carbonic acid and the aqueous solution of carbon dioxide. On the other hand, textual analysis showed that most of high school textbooks used carbonic acid as an example of weak acid and buffer solution of the blood but none of them distinguished the carbonic acid from the aqueous solution of carbon dioxide. Only one textbook, however, tiered two species in the chemical equation.

Aims Paraquat (PQ) is known to induce pulmonary injury via a redox cyclic reaction. The present study was aimed to determine the protective effects of quercetin against PQ-induced pulmonary injury in association with its antioxidant activity. Main methods Male rats were challenged acutely by PQ (50 mg/kg, i.p.) with or without quercetin post-treatment. Pulmonary heme oxygenase-1 (HO-1) expression, malondialdehyde (MDA) level, and the total oxyradical scavenging capacity (TOSC) toward hydroxyl, peroxyl radicals and peroxynitrite were measured 24 h after PQ treatment. Different groups of rats were instilled with PQ (0.5 mg/kg) directly into the right lung. Quercetin was administered to the rats daily for 14 days after PQ instillation. Serum NO, pulmonary glutathione (GSH) and 4-hydroxyproline (4-HP) concentrations were quantified in conjunction with histopathological examination to determine the fibrotic changes in lung. Key findings Pulmonary MDA level and HO-1 expression were elevated and the TOSC was reduced rapidly by an intraperitoneal dose of PQ. These changes were inhibited by quercetin post-treatment. In rat lungs instilled with PQ 14 days before, NO, MDA and 4-HP were elevated, and GSH was reduced, which were all inhibited significantly by daily quercetin treatment. Histopathological examination also revealed that quercetin ameliorated the increase in fibroblast distribution and collagen deposition in the lungs instilled with PQ. Significance The present results demonstrate that quercetin administration to rats effectively inhibits the development of PQ-induced pulmonary injury most probably via its antioxidant activity.

This study aimed to investigate the transcription and representation of inorganic compounds in selected 13 science and chemistry textbooks for the 10-12th grades. Based on the comparison of each grade textbook, the species, the number of the chemical per page, and the transcription method of inorganic compounds were listed. Results found that the average numbers of inorganic compounds and the transcription method are 49.6 and 89.8 in Science, 69.0 and 98.3 in Chemistry I, and 100.0 and 164 in Chemistry II, respectively. The numbers of the chemicals per page in Chemistry I and II, however, were 0.28 unexpectedly, while one of the compounds in Science was 0.68. From these results we glimpse that the text of Science appears to be much heavier than ones of Chemistry I and II for the student to read the content. In addition, the most representative inorganic compounds, hydrochloric acid, sodium hydroxide and sodium chloride were selected and analyzed by the expression modes from the modified Johnstone's triangle model. The descriptive difference of three complexes between grades was found to be negligible.

Metal−organic frameworks (MOFs) are a rapidly growing class of microporous materials. Various MOFs with tailored nanoporosities have recently been developed as potential storage media for natural gases and hydrogen. However, wider applications have been limited because even atmospheric moisture levels cause MOF instability, and unexpectedly low H2 storage capacity, at 298 K. To overcome these problems, we synthesized a hybrid composite of acid-treated multiwalled carbon nanotubes (MWCNTs) and MOF-5 [Zn4O(bdc)3; bdc = 1,4-benzenedicarbocylate] (denoted MOFMC). In a successful synthesis, well-dispersed MWCNTs in dimethylformamide (DMF) were mixed with a DMF solution of zinc nitrate tetrahydrate and terephthalic acid. The MOFMCs obtained had the same crystal structure and morphology as those of virgin MOF-5, but exhibited a much greater Langmuir specific surface area (increased from 2160 to 3550 m2/g), about a 50% increase in hydrogen storage capacity (from 1.2 to 1.52 wt % at 77 K and 1 bar and from 0.3 to ...

The purpose of this study is to investigate the transcription and expression about the nomenclature of inorganic compounds in five science textbooks for the 10th grade. Based on the comparison of each text content, the name, the appearance frequence, and the transcription method of inorganic compounds were listed. The results found that there are 48.8 inorganic chemical compounds and 86 transcription methods on the average. Representative inorganic compounds in the text were hydrochloric acid, sodium hydroxide and sodium chloride in order. They could be chemically transcribed by the seven expression modes which were obtained from the Johnstone’s triangle model.

The performance of an autothermal thermophilic aerobic digestion (ATAD) system was studied to determine if nitrogen loss, as ammonia, was affected by an exhaust gas condenser. The system was run with and without a condenser while treating 8 m 3 of piggery slurry for 8 days. The system with a condenser (SWC) maintained the reactor temperatures above 40°C for 2 days during the 8 days run, while the system without a condenser (SWOC) remained above 40°C for 6 days. The SWC maintained the reactor temperatures mostly at mesophilic conditions while the SWOC at thermophilc conditions. Differences in operation conditions for the two runs were mainly caused by differences in atmospheric temperatures. Soluble chemical oxygen demand (SCOD) and volatile solids (VS) removal efficiencies of the SWC (SCOD: 62%, VS: 41%) were higher than those of the SWOC (SCOD: 40%, VS: 20%). The total Kjeldal nitrogen (TKN) removal efficiency of the SWC (7%) was less than that of the SWOC (25%). The concentration of total volatile fatty acids (VFA) in the SWC was observed to be lower than the threshold value of 0.23 g total VFA/L after 6 days, while the SWOC progressed below the threshold value after 3 days. No offensive odor emissions were observed in either run, which suggest that the use of the ATAD system may be a good odor removal strategy. (Asian-Aust. J. Anim. Sci. 2006. Vol 19, No. 2 : 273-279)

Syntheses and characterizations of sol–gel precursors of Sr2CeO4 were carried out. Each molecular precursor, [Sr2Ce(OCH2CH2OCH3)8] (1), [Sr2Ce(O i Pr)8] (2) and [Sr2Ce2(O i Pr)12( i PrOH)4] (3) was prepared from mixtures of Sr complexes and cerium(IV) alkoxides. The molecular structure of 3 showed that [CeO6] octahedra are connected with distorted [SrO6] octahedra by sharing edges with oxo bridges. X-ray powder diffraction patterns and spectrofluorometry were used to determine the evolution of structure from the precursor molecules to the luminescent oxides. The luminescent strontium cerium oxides were derived at relatively mild reaction conditions (700 °C for 1 h), and complete conversion was observed at 1000 °C for 1 h from these precursors. Comparing the spectra of the oxides derived from 2 and 3, the emission intensity of the oxide derived from 2 is much stronger.

The photocatalytic decomposition of octadecyltrichlorosilane (OTS) based self-assembled monolayer formed on TiO2 has been studied using atomic force microscopy(AFM), X-ray photoelectron spectroscopy (XPS), and contact angle analysis. The TiO2 thin films were grown on Si(100) substrates by atomic layer deposition from titanium isopropoxide and water. Densely packed alkylsiloxane monolayers similar in quality to those on SiO2 are formed on TiO2. It is found that the monolayers on TiO2 are decomposed much faster than those on SiO2 under UV irradiation of 254 nm in air. The OTS-based SAMs on TiO2 are decomposed through the photocatalytic oxidation of the alkyl chains with a gradual and homogeneous reduction in chain length. After the complete photodecomposition of the OTS−SAMs, the siloxane headgroups remain on the TiO2 surface. The observation indicates that the titanium oxide, a well-known photocatalyst for organic pollutant treatment, efficiently decomposes the alkylsiloxane monolayers under UV irradiation...

The thermal decomposition of alkylsiloxane self-assembled monolayers in air has been studied using atomic force microscopy, X-ray photoelectron spectroscopy, and contact angle analysis. It is found that the monolayers are stable in air up to about 200 °C. Above 220 °C the monolayers primarily decompose through C−C bond cleavage, with a gradual reduction in chain length. The siloxane headgroups remain on the surface following the decomposition of hydrocarbon fragments in the monolayers.

Studies on subtle spacer ligand effects of AgCF 3 SO 3 with 3,3'-Py 2 X (X = O vs S) have been carried out. The reaction of AgCF 3 SO 3 with 3,3'-Py 2 O and 3,3'-Py 2 S produces [Ag(CF 3 SO 3 )(3,3'-Py 2 O)] and [Ag(3,3'-Py 2 S)] (CF 3 SO 3 ), respectively. Crystallographic characterization of [Ag(CF 3 SO 3 )(3,3'-Py 2 O)] (monoclinic P1, a = 8.405(2) A, b = 10.714(2) A, c = 18.031(2) A, α = 77.36(2), β = 107.83(2)°, γ = 66.92(2), V = 1438.0(5) A 3 , Z = 2, R = 0.0486) reveals that the skeletal structure is an anion-bridged double-strand. The double-strands are packed like a plywood. The framework of [Ag(3,3'-Py 2 S)](CF 3 SO 3 ) (orthorhombic Pcab, a = 17.330(2) A, b = 8.640(1) A, c = 19.933(6) A, V = 2985(1) A 3 , Z= 8, R = 0.0437) is a sinusoidal single-strand. The formation of each coordination polymer appears to be primarily associated with the donating ability and the conformational energy barrier of the spacer ligands. Thermal analyses indicate that [Ag(CF 3 SO 3 )(3,3'-Py 2 O)] and [Ag(3,3'-Py 2 S)](CF 3 SO 3 ) are stable up to 250 °C and 210 °C, respectively. For the anion exchangeability, the nature of the spacer ligand is more significant factor than the distance of silver(I)...triflate.

We introduce a method for direct patterning of Ni electrodes through selective laser direct writing (LDW) of NiO nanoparticle (NP) ink. High-resolution Ni patterns are generated from NiO NP thin films by a vacuum-free, lithography-free, and solution-processable route. In particular, a continuous wave laser is used for the LDW reductive sintering of the metal oxide under ambient conditions with the aid of reducing agents in the ink solvent. Thin (∼40 nm) Ni electrodes of glossy metallic surfaces with smooth morphology and excellent edge definition can be fabricated. By applying this method, we demonstrate a high transmittance (>87%), electrically conducting panel for a touch screen panel application. The resistivity of the Ni electrode is less than an order of magnitude higher compared to that of the bulk Ni. Mechanical bending test, tape-pull test, and ultrasonic bath test confirm the robust adhesion of the electrodes on glass and polymer substrates.

Microwave spectra of the three Group 13 metal cyanide pairs AlNC/AlCN, GaNC/GaCN, and InNC/InCN have been measured in the frequency range 6–25 GHz using a pulsed jet cavity Fourier transform microwave spectrometer. The molecules were prepared by ablating the metal with a pulsed Nd:YAG laser and allowing the vapor to react with cyanogen or acetonitrile contained in the Ar backing gas of the jet. The spectra are those of linear molecules. Rotational constants, centrifugal distortion constants, and nuclear quadrupole coupling constants have been precisely evaluated. Molecular geometries determined from the rotational constants using a linear model have revealed unexpectedly short NC bond lengths for the isocyanides, MNC, and are interpreted in terms of a broadened potential well for the bending mode of these molecules. This interpretation is confirmed with ab initio calculations. The centrifugal distortion constants are consistent with this picture. A new formulation of the rigid bender model has produced plausible values for bond lengths and bending amplitudes for the isocyanides. The 14 N quadrupole coupling constants are discussed in terms of the approximate bending amplitudes. A description of the bonding in the molecules has been obtained using Townes–Dailey theory.

Infinite molecular helices [Ag(3,3'-Py2S)]X (3,3'-Py2S = 3,3'-thiobispyridine; X- = BF4-, ClO4-, and PF6-) have been rationally constructed or induced. Crystallographic characterization (X- = BF-, monoclinic P2(1)/n, a = 8.946(3) A, b = 14.130(2) A, c = 10.124(2) A, beta = 107.83(2) degrees, V = 1218.3(5) A3, Z = 4, R = 0.0351; X- = ClO4-, monoclinic P2(1)/n, a = 8.884(1) A, b = 14.305(3) A, c = 10.110(1) A, beta = 106.78(1) degrees, V = 1230.1(3) A3, Z = 4, R = 0.0417; X- = PF6-, monoclinic P2(1)/c, a = 10.959(2) A, b = 9.808(2) A, c = 14.065(3) A, beta = 112.03(2) degrees, V = 1401.4(5) A3, Z = 4, R = 0.0442) reveals that the skeletal structure is an oblong cylindrical cationic helix consisting of alternating Ag(I) and 3,3'-Py2S species and that its counteranions are pinched in two columns inside each helix. The formation of the helical coordination polymer appears to be primarily associated with a suitable combination of the skewed conformer of 3,3'-Py2S and the potential linear geometry of the N-Ag(I)-N bond. However, the framework of the nitrate analogue [Ag(3,3'-Py2S)NO3] (monoclinic P2(1)/c, a = 8.177(2) A, b = 10.291(1) A, c = 14.771(2) A, beta = 102.19(1) degrees, V = 1214.9(4) A3, Z = 4, R = 0.0300) is a two-dimensional network consisting of an 18-membered ring unit, where each 3,3'-Py2S acts as a N,N',S- tridentate ligand connecting three tetrahedral silver(I) ions with the monodentate nitrate weakly bonded to the silver (Ag.O = 2.65(1) A) rather than acting as a counteranion. The anion exchange of [Ag(3,3'-Py2S)NO3] with BF4-, ClO4-, or PF6- has been accomplished in aqueous media. The two-dimensional networks are easily converted into the helices via the anion exchange, but the reverse anion exchange proceeds slightly. Thermal analyses indicate a relationship between the thermal stabilities and the structural properties.

CM1 (centrocyte/-blast marker 1) defined by a mAb developed against concanavalin-A activated PBMC, is expressed specifically on some tonsillar germinal center (GC) B cells. In single flow cytometric analysis, the bone marrow did not express these molecules nor did the PBMC or the thymocytes. The peripheral B lymphocytes showed more than 90% positive, while the peripheral T lymphocytes showed approximately 60% positive at 48 h after activation by PMA/ionomycin, respectively. A western blot analysis and an immunoprecipitation for CM1 showed a band at 70 kDa. Cross-linking of CM1 with anti-CM1 mAb induced apoptosis of the GC B cells (CD38(+)IgD(-)). Immunohistochemical staining revealed that the CM1 molecule is distributed over the entire area except the proximal dark zone of the tonsillar germinal centers. These results suggest that the CM1 molecule might be involved in differentiation of the germinal center B cells as one of the novel centrocyte markers.

Studies have been carried out on unique molecular non-rigidity of Cp*RhIII(PyS)2 (PyS=pyridine-2-thiolato). One PyS ligand bonds to the rhodium ion in an S-monodentate mode (RhS(2)=2.3799(9) A) while the other ligand chelates to the metal in an N,S-bidentate mode (RhS(1)=2.4380(9); RhN(1)=2.089(2) A). Both PyS ligands possess a significant contribution from the thiol tautomer in the solid state. Even though the conformation and configuration of the molecule are still retained in solution, an unusual metal-mediated tautomeric non-rigidity for the PyS region is observed in the solution around room temperature.

Exocyclic tris(bidentate) ligands attached to a cyclotriphosphazene skeleton have been prepared and characterized. The cobalt complexes of the ligand have an unusual structure and demonstrate CoIII/CoII equilibrium over a wide temperature range.

Initial experiments on infrared matrix-assisted laser desorption/ionization mass spectrometry (IR-MALDI) using a free electron laser in the analysis of low-molecular-weight compounds are reported. Mass spectra from samples of ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA) and a phosphate salt were obtained. Low molecular weight (LMW) compounds are of similar mass as the molecular weight of the matrix compound and interference between matrix and analyte ions can degrade MALDI sensitivity. Under optimal conditions, however, we find little interference and that often the analyte signal exceeds the matrix signal, a result also observed in UV-MALDI of these compounds. In the IR-MALDI of EDTA near 3.0 μm the FEL results are similar to those obtained using a fixed frequency 2.94 μm Er:YAG laser of 200 ns pulse duration. However, the tunable FEL laser can selectively excite particular vibrational modes of the matrix (e.g., an OH or CO stretch) or of residual water contained within the crystalline MALDI sample. This capability was used to explore possible vaporization and ionization mechanisms of IR-MALDI for EDTA.

The reaction of hexachlorocyclotri(λ5-phosphazene), N3P3Cl6, with a series of pyrimidine-2-thiol in the presence of triethylamine in boiling tetrahydrofuran solution affords only a geminal isomer, N3P3(N–S)2Cl4 (N–S = 2-pyrimidinylthio (pms), 4,6-dimethyl-2-pyrimidinylthio (dmpms), and trifluoromethyl-2-pyrimidinylthio (fmpms)) in high yield. The molecular structures of N3P3(pms)2Cl4 (monoclinic P21/n, a = 7.686(2), b = 28.236(7), c = 8.760(2) A, β = 99.87(2)°, V = 1873.2(8) A3, Z = 4, R = 0.052) and N3P3(dmpms)2Cl4 (triclinic , a = 8.698(3), b = 9.630(3), c = 14.179(6) A, α = 100.88(3), β = 92.83(3), γ = 103.84(3)°, V = 1126.9(7) A3, Z = 2, R = 0.049) have been solved. The crystal structures disclose that the nitrogen atom of the 2-pyrimidinylthiol group significantly interacts with the phosphorus atom of the cyclotri(phosphazene) ring within the sum of the van der Waals radii (3.40 A). The P…N intramolecular interaction of N3P3(dmpms)2Cl4 (P(1)–N(5), 3.109(4); P(1)–N(7), 3.126(4) A) is considerably long...

The structure of KNb5O13 consists of two-dimensional slabs of edge- and corner-sharing NbO6 octa­hedra, and these slabs are inter­connected to form the three-dimensional framework. The K+ cations reside in the empty channels. Among the three crystallographically independent Nb atoms, the coordination around the Nb atom bridging the slabs is more regular than those of the other Nb atoms. A bond-valence calculation indicates that the charge balance should be represented by [K+][Nb5+]5[O2−]13.

The preparation and characterization of [Co(μ-bpym)(dbbq)2] and [{Co(dbbq)2}2(μ-bpym)] (bpym = 2,2′-bipyrimidine; dbbq = 3,6-di-t-butyl-1,2-benzoquinone) have been established. The temperature-depe...

Intermittent plasma growth hormone (GH) pulses, which occur in male but not female rats, activate liver Stat 5 by a mechanism that involves tyrosine phosphorylation and nuclear translocation of this latent cytoplasmic transcription factor (Waxman, D. J., Ram, P. A., Park, S. H., and Choi, H. K. (1995) J. Biol. Chem. 270, 13262-13270). We demonstrate that physiological levels of GH can also activate Stat 1 and Stat 3 in liver tissue, but with a dependence on the dose of GH and its temporal plasma profile that is distinct from Stat 5 and with a striking desensitization following a single hormone pulse that is not observed with liver Stat 5. GH activation of the two groups of Stats leads to their selective binding to DNA response elements upstream of the c-fos gene (c-sis-inducible enhancer element; Stat 1 and Stat 3 binding) and the beta-casein gene (mammary gland factor element; liver Stat 5 binding). In addition to tyrosine phosphorylation, GH is shown to stimulate phosphorylation of these Stats on serine or threonine in a manner that either enhances (Stat 1 and Stat 3) or substantially alters (liver Stat 5) the binding of each Stat to its cognate DNA response element. These findings establish the occurrence of multiple, Stat-dependent GH signaling pathways in liver cells that can target distinct genes and thereby contribute to the diverse effects that GH and its sexually dimorphic plasma profile have on liver gene expression.

Growth hormone (GH) exerts sexually dimorphic effects on liver gene transcription that are regulated by the temporal pattern of pituitary GH release, which is intermittent in male rats and nearly continuous in females. To investigate the influence of these GH secretory patterns on intracellular hepatocyte signaling, we compared the pattern of liver nuclear protein tyrosine phosphorylation in male and female rats. An Mr ~93,000 polypeptide, p93, was found to be tyrosine phosphorylated to a high level in male but not female rats. GH, but not prolactin, rapidly stimulated p93 tyrosine phosphorylation in hypophysectomized rats. Intermittent plasma GH pulses triggered repeated p93 phosphorylation, while continuous GH exposure led to desensitization and a dramatic decline in liver nuclear p93. p93 was cross-reactive with two monoclonal antibodies raised to mammary Stat 5, whose tyrosine phosphorylation is stimulated by prolactin. Intermittent GH pulsation translocated liver Stat 5/p93 protein from the cytosol to the nucleus and also activated its DNA binding activity, as demonstrated using a mammary Stat 5-binding DNA element derived from the β-casein gene. p93 is thus a liver-expressed, Stat 5-related DNA binding protein that undergoes tyrosine phosphorylation and nuclear translocation in response to intermittent plasma GH stimulation and is proposed to be an intracellular mediator of the stimulatory effects of GH pulses on male-specific liver gene expression.

The development of technetium-99m-labeled imaging agent for brain receptors is still a formidable challenge in radiopharmaceutical research. The specific serotonin receptor-binding imaging agent, particularly the 5-HT2 receptor antagonist, attracts great attention because it is known to be involved in many neurological and psychological diseases including Alzhemier’s disease and depression. Many imaging agents suitable for positron emission tomography bearing C and F as a radiotracer were developed on the basis of known 5HT2A receptor antagonist. Imaging agents for single photon emission computed tomography (SPECT) labeled with I or 125 I were also developed. Preparation of technetium-99m-labeled imaging agent for the 5HT2A receptor stems from mimicking the receptor binding compounds as biologically active molecules (BAMs) which bind to the metals to form proper metal complex with other ligands to accommodate all coordination sites. A novel “3+1” mixed ligand rhenium oxo complex can be generated from the combination of tridentate ligand and monodentate BAM. A few reports describe the synthesis and evaluation of technetium(V) and rhenium(V) complex for 5HT2A serotonin receptor binding based on the ketanserin (1) and its derivatives. A ligand used for BAM based on ketanserin can be designed on the basis of two structural units i.e. quinazoline as part A and phenyl piperidinyl ketone as part B. Either part A or B can be used for BAM while the other part goes as metal binding site. Among two approaches, part B, phenyl piperidinyl ketone site is more favorable for biologically active ligand because it is longer and adjustable. The size and structural similarity to replace part A quinazoline ring is more acceptable and its metal complex with technetium99m showed better imaging agent. Recently ketanserin surrogate 2 showed very selective and potent binding activity toward 5HT2A that may serve as a template to design a new technetium-99m-labelled imaging agent. Triazolopyridin-3one can be replaced by the relatively small metal complex while the pendent 1-alkyl-4-phenylpyrazine is served as a biologically recognizable site. In this study, we synthesized and characterized a novel “3+1” mixed ligand rhenium oxo complex with 2-mercaptoethyl sulfide as a ligand and 3-(4-m-chlorophenyl piperazin1-yl) butane-1-thiol as a biologically active co-ligand. 3-(4-m-Chlorophenyl piperazin-1-yl)butane-1-thiol 4 as a BAM was designed on the basis of prototype 5HT2A serotonin specific antagonist 2 that was originated from ketanserin 1 as its analog. The synthesis of monodentate thiol ligand 4 was planned to achieve by the reductive coupling reaction between 4-mercaptobutane-2-one and 1m-phenylpiperazine. At first, ethyl acetoacetate was protected with ethyleneglycol followed by sequential reactions of ester reduction and tosylation to afford 2-[2-methyl-[1,3]-dioxolane-2yl]ethyl p-toluenesulfonate (5). Tosyl group was replaced by potassium thiolacetate to introduce sulfur that will be ended as binding site to metal. Removal of acetyl group from thiolacetate 6 by carbonate in MeOH did not give the expected free thiol but its dimerized disulfide was formed 7. Then diketone 8 was yielded by treatment of hydrochloric acid in acetone. Reductive cleavage of disulfide at this stage was not quite successful. Instead of reductive amination with two mole equivalents of 1-m-chlorophenylpiperazine coupling

The temperature dependence of the optical properties for amorphous silicon is studied at wavelengths of 632.8 and 752 nm. Both the refractive index and extinction coefficient increase linearly with temperature for 752 nm, while the refractive index decreases and the extinction coefficient increases for 632.8 nm. The rate of increase of the extinction coefficient at 632.8 nm is twice as much as that for 752 nm.

We report experimental studies on laser scribing of thin film solar cells using various types of short pulsed lasers (nanosecond, picosecond, and femtosecond temporal pulse widths), aiming to determine the optimum laser parameters for the scribing of multilayer structures of amorphous silicon (a-Si) and copper indium diselenide (CIS) based solar cells. Detailed laser scribing parameters such as repetition rate of the laser pulses, scanning speed of the sample and laser beam, individual pulse energy, laser wavelength, and direction of laser illumination (either from film side or from substrate side) are examined. Characteristics of each scribing conditions are evaluated in terms of morphology by atomic force microscopy (AFM) and scanning electron microscopy (SEM), chemical species analysis by Energy Dispersive X-ray Spectroscopy (EDS), and electrical conductance of interconnects by conductive AFM (c-AFM) and contact resistance measurement to determine the optimal laser scribing conditions. Further issues on defects in the films such as re-deposited debris, elevated molten rim and delamination, thermal damage to surrounding and/or underlying layers and inter-diffusion of materials at the interface are discussed on the basis of thermal/mass diffusion, thermal stress, and ablation-induced plasma formation, in order to demonstrate an efficient laser scribing of P1/P2/P3 of thin film solar cells.

Nonalcoholic fatty liver is involved in the development of nonalcoholic steatohepatitis and chronic liver injury. Impairment of hepatic transsulfuration reactions is suggested to be critically linked with alcoholic liver injury, but its role in nonalcoholic fatty liver remains unknown. We examined the early changes in sulfur-amino acid metabolism and their implication in nonalcoholic fatty liver disease (NAFLD). Male rats were provided with a standard liquid diet or a high-fat liquid diet (HF) for 3 wk. An additional group of rats received the HF diet supplemented with betaine (1%). HF diet intake elevated hepatic triglyceride and serum tumor necrosis factor-alpha (TNFalpha) concentrations. Antioxidant capacity of liver cytosol against hydroxyl and peroxyl radicals was reduced significantly. Hepatic S-adenosylmethionine (SAM) and glutathione (GSH) decreased, but hypotaurine and taurine concentrations increased. Methionine adenosyltransferase (MAT) activity, not its concentration, was depressed, whereas both activity and concentration of cysteine dioxygenase and GSH S-transferase were elevated. Betaine supplementation of the HF diet inhibited hepatic fat accumulation and serum TNFalpha elevation. The decrease in cytosolic antioxidant capacity was also prevented. MAT activity and its concentration were induced significantly. Hepatic SAM and GSH increased and elevation of hypotaurine and taurine was depressed. The results indicate that the metabolism of S-containing substances is significantly disturbed by the HF diet, suggesting a causal role of impairment of hepatic transsulfuration reactions in NAFLD. Betaine supplementation protects the liver from nonalcoholic steatosis and oxidative stress most probably via its effects on the transsulfuration reactions.

Background/Aims Oxidative stress via generation of reactive oxygen species is suggested to be the major mechanism of alcohol-induced liver injury. We investigated the effects of glutathione peroxidase-1 and catalase double deficiency (Gpx-1 −/− /Cat −/− ) on liver injury and changes in the sulfur amino acid metabolism induced by binge ethanol administration. Methods Ethanol (5g/kg) was administered orally to the wild-type and the Gpx-1 −/− /Cat −/− mice every 12h for a total of three doses. Mice were sacrificed 6h after the final dose. Results The Gpx-1/Cat deficiency alone increased malondialdehyde levels in liver significantly. Hepatic methionine adenosyltransferase (MAT) activity and S -adenosylmethionine levels were decreased, however, glutathione contents were not changed. Ethanol administration to the Gpx-1 −/− /Cat −/− mice increased the elevation of serum alanine aminotransferase activity, plasma homocysteine levels, hepatic fat accumulation and lipid peroxidation compared with the wild-type animals challenged with ethanol. Also the reduction of MAT activity and S -adenosylmethionine levels was enhanced, but MATI/III expression was increased significantly. Conclusions The results indicate that Gpx-1 and Cat have critical roles in the protection of liver against binge ethanol exposure. Augmentation of ethanol-induced oxidative stress may be responsible for the impairment of the transsulfuration reactions and the aggravation of acute liver injury in the Gpx-1 −/− /Cat −/− mice.

For the first time, a single alkoxide sol–gel precursor solution for the ferroelectric strontium bismuth tantalate (SrBi 2 Ta 2 O 9 , SBT) was synthesized and utilized for the fabrication of its thin films. The precursor was prepared from a 2-methoxyethanol solution of Sr(OCH 2 CH 2 OCH 3 ) 2 , Bi(OCH 2 CH 2 OCH 3 ) 3 , and Ta(OCH 2 CH 2 OCH 3 ) 5 . 1 H and 13 C NMR spectra of the precursor in benzene show only one set of alkoxy groups, indicating the same chemical environment in solution. This observation suggests that it is a single sol–gel precursor, which is ideal for the sol–gel processing of SBT thin films. The SBT films derived from this precursor present outstanding ferroelectric properties and surface morphology.

Twelve zeolitic imidazolate frameworks (ZIFs; termed ZIF-1 to -12) have been synthesized as crystals by copolymerization of either Zn(II) (ZIF-1 to -4, -6 to -8, and -10 to -11) or Co(II) (ZIF-9 and -12) with imidazolate-type links. The ZIF crystal structures are based on the nets of seven distinct aluminosilicate zeolites: tetrahedral Si(Al) and the bridging O are replaced with transition metal ion and imidazolate link, respectively. In addition, one example of mixed-coordination imidazolate of Zn(II) and In(III) (ZIF-5) based on the garnet net is reported. Study of the gas adsorption and thermal and chemical stability of two prototypical members, ZIF-8 and -11, demonstrated their permanent porosity (Langmuir surface area = 1,810 m 2 /g), high thermal stability (up to 550°C), and remarkable chemical resistance to boiling alkaline water and organic solvents.

The transient temperature field development during heating of an amorphous silicon (a‐Si) film, deposited on a fused quartz substrate by pulsed excimer laser irradiation is studied. Experimental optical transmission data are compared with heat transfer modeling results. The temperature‐dependence of the material complex refractive index through the thin film thickness is taken into account.

We proposed in situ generation of cyclohexenyl peroxide as a surface oxidant in solution of CdSe quantum dots and verified it by monitoring emission wavelengths and intensities of CdSe and CdSe–ZnS...

We have succeeded in assembling a new trigonal aryne ligand, triphenylene-2,6,10-tricarboxylic acid (H3TTCA) with metal ions to give M3(TTCA)2·6DMF·7H2O (M = Zn2+ and Cd2+) (DMF = N,N-dimethylforma...

Calcium carbonate (CaCO3) and its structural relatives, the phosphates and hydroxyapatites, are natural crystals which are similar to the minerals found in such hard tissues as teeth and bone. We have recently demonstrated that laser- induced material removal in calcium carbonate occurs with high efficiency when irradiating with a free-electron laser at the fundamental asymmetric stretch mode of the carbonate group near 7 micrometers ; related studies show that the same thing is true in the isoelectronic sodium nitrate, and we expect it to operate in the phosphates as well when irradiated near the resonant 9 micrometers band. The mechanism of material removal appears to be the ejection of CO followed by a calcination reaction which produces CaO. Among the features which make CaCO3 such an interesting model material is that it also has a characteristic, temperature-dependent thermoluminescence - thus making it possible, by the study of the light emitted by the crystal prior to and after ablation, to estimate the temperature reached by the crystal in the early stages of laser ablation. Wavelength-dependent photoluminescence, photoacoustic and plume-spectroscopic studies show that efficient evaporative 'hole drilling' occurs at the infrared wavelengths corresponding to carbonate or nitrate vibration modes. However, where electronic or vibrational defects are excited by visible or infrared lasers, respectively, the mechanisms of material removal are photomechanical fracture in the former case and exfoliation or subsurface explosive vaporization in the latter.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An air-stable iron cluster alkoxide complex Na2[Fe6(OCH2CH2OCH3)18(µ6-O)] was prepared from the reaction of iron(III) chloride and sodium 2-methoxyethoxide. The complex was used to prepare Sr2FeMoO6, which spin-coated film shows a very high positive magnetoresistance of 25% with a magnetic field of 0.8 T at 300 K.

The title compound, C(26)H(18)N(4)O(5), can be regarded as an extended ether with two terminal nitro groups. The two aryl rings bonded to the central O atom form a dihedral angle of 75.72 (6)°, and the terminal nitro groups are slightly twisted [by 6.4 (2) and 3.3 (3)°] from the benzene rings to which they are attached. The crystal packing exhibits weak inter-molecular C-H⋯O hydrogen bonds and π-π inter-actions [centroid-centroid distances = 3.794 (3) Å].