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Pt nanoparticles of diameter 0.5−1.5 nm were dispersed homogeneously on the inner and outer surfaces of alkali metal titanate nanotubes (M2Ti3O7, M = Li+, Na+, and K+) by ion exchange with Pt(NH3)2Cl2 followed by calcination in ambient air at 673 K and reduction in H2 at 448 K. Both XPS and DRIFTS revealed that these titanate nanotubes donated their electrons to the Pt particles, yielding a negative Pt oxidation state, and that the degree of electron donation increased with the size of the alkali metal cation. The high electron density of the Pt particles promoted the activation of both C═C and C═O functional groups in cinnamaldehyde. Therefore, the order of the catalytic activity in the hydrogenation of cinnamaldehyde was Pt/KTNTs > Pt/NaTNTs > Pt/LiTNTs. Since the Pt particles were very small, Pt/MTNTs selectively hydrogenated the C═C bond, yielding a hydrocinnamaldehyde with selectivities of 80−87% (at cinnamaldehyde conversions of 27−50%). The alkali metal ions of the titanate nanotubes were able to m...

Montmorillonite K10 is a very inexpensive and readily available reagent and efficiently catalyzes the Michael addition of indoles to nitroolefins under solvent-free conditions. Reasonable to excellent yields of the desired products were obtained in most cases.

Three‐component Mannich‐type reaction of aldehydes, aromatic amines, and silyl enolate proceeded smoothly to afford β‐amino carbonyl compounds with good yields in the presence of a catalytic amount of HBF4‐SiO2.

Histone deacetylase (HDAC) inhibitors such as trichostatin A and valproic acid modulate transcription of many genes by inhibiting the activities of HDACs, resulting in the remodeling of chromatin. Yet this effect is not universal for all genes. Here we show that HDAC inhibitors suppressed the expression of steroidogenic gene CYP11A1 and decreased steroid secretion by increasing the ubiquitination and degradation of SF-1, a factor important for the transcription of all steroidogenic genes. This was accompanied by increased expression of Ube2D1 and SKP1A, an E2 ubiquitin conjugase and a subunit of the E3 ubiquitin ligase in the Skp1/Cul1/F-box protein (SCF) family, respectively. Reducing SKP1A expression with small interfering RNA resulted in recovery of SF-1 levels, demonstrating that the activity of SCF E3 ubiquitin ligase is required for the SF-1 degradation induced by HDAC inhibitors. Overexpression of exogenous SF-1 restored steroidogenic activities even in the presence of HDAC inhibitors. Thus, increased SF-1 degradation is the cause of the reduction in steroidogenesis caused by HDAC inhibitors. The increased SKP1A expression and SCF-mediated protein degradation could be the mechanism underlying the mode of action of HDAC inhibitors.

An efficient synthesis of dihydropyrimidinones from the aldehyde, 1,3-dicarbonyl compound and urea (thiourea) under solvent-free conditions, using fluoroboric acid as the catalyst, is described. Compared with the classical Biginelli reaction conditions, this new protocol has the advantage of high yields, short reaction time and simplicity in the experimental procedure.

Sulfamic acid efficiently catalyzes the three‐component condensation reaction of aldehydes, 1,3‐dicarbonyl compounds, and urea/thiourea under solvent‐free conditions to afford the corresponding dihydropyrimidinones and thio‐derivatives in high yields. Silica sulfuric acid is also found to be an efficient catalyst for the Biginelli reaction under solvent‐free conditions. Compared to the classical Biginelli reaction conditions, this new method consistently has the advantage of giving good yields and requiring short reaction times.

Summary Objectives The purpose of this study was to determine the validity and accuracy of mixing opaque feldspathic dental ceramic to obtain specific shades using two methods: (1) Concentration Additivity of Optical Parameters (CALAB) and (2) Concentration Additivity of Kubelka-Munk Optical Coefficients (CAK/S). Methods A total of 25 opaque feldspathic dental ceramic specimens were fabricated by mixing six different pure shades in different concentrations. The reflectance spectra were measured and the actual CIELAB L *, a * and b * coordinates were obtained for the 25 specimens. The CALAB and CAK/S methods were used to predict the L *, a * and b * values with reference to the concentrations of the pure shades. Correlation analysis was carried out between the actual and predicted L *, a * and b * values for both methods. The color differences (Δ E *) between actual and predicted L *, a * and b * values were also calculated and analyzed using repeated measures ANOVA. Results Pearson's correlation coefficients between predicted and actual values for both methods were greater than 0.98. The mean Δ E*s were 0.24 (0.11) for CALAB method and 0.21 (0.11) for the CAK/S method. The repeated measures ANOVA revealed a statistically significant difference ( P =0.0213) between the mean Δ E*s from the two methods. Significance Both methods produced mean Δ E*s between the actual and predicted methods that were below the threshold of human perceptibility. The simpler CALAB method can be used to determine the opaque ceramic mixture for specific shades with accuracy.

Steroidogenic factor 1 (SF-1 or NR5A1), is a Ftz-F1 member of the nuclear receptor superfamily that plays essential roles in endocrine development, steroidogenesis, and gonad differentiation. We investigated modifications that control SF-1 function and found that SF-1 could be conjugated by SUMO-1 both in vitro and in vivo. SF-1 was modified predominantly at Lys(194) and much less at Lys(119) when free SUMO-1 was supplied. Mutations of Lys(194) and Lys(119) enhanced transcriptional activity of SF-1, although the DNA binding activity of SF-1 was not affected. Sequences around Lys(194) and Lys(119) both repressed transcription intrinsically. The Lys(194) motif repressed transcription more efficiently than the Lys(119) domain, consistent with its ability to be a better substrate for SUMO conjugation. Thus, SUMO modification of SF-1 correlates with transcriptional repression. Wild-type but not conjugation-deficient SF-1 was localized at the nuclear speckles together with SUMO-1. Thus, SUMO-1 conjugation could also target SF-1 into nuclear speckles. Collectively, these results suggest that SUMO modification at the repression domains targets SF-1 to nuclear speckles; this could be an important mechanism by which SF-1 is regulated.

The hydroxyl radical (HO⋅), generated from the Fenton-like catalysis of hydrogen peroxide (H2O2), is the major reactant involved in the oxidation of toxic organic contaminants. This study evaluated the effects of H2O2 doses and types of iron oxides on the yields and production rates of HO⋅ radicals at molar ratio of H2O2/total iron oxide=0.2-9.7 and pH=7. The results showed that for both ferrihydrite and goethite, the yields and production rates of HO⋅ radicals were in the order of 10-12mM and 1-5×10-14mM/S, respectively, and irrelevant to the initial H2O2 dose. However, a higher H2O2 dose was required in aquifer sand to produce the same level of HO⋅ radicals. The molar transformation ratios of H2O2 to HO⋅ radicals for three different iron oxides all ranged from 10-15 to 10-13, and occurred at low H2O2 doses. The yield and production rate of HO⋅ radicals showed no significant correlation with the first-order decay constant of H2O2. This indicated that the rate of H2O2 decomposition was not a suitable para...

An organocatalytic enantioselective Michael reaction of malonates to 3-nitro-2H-chromenes has been developed; the products could be obtained in high yields and good enantioselectivities.

RFID is a non-contact technology using radio frequencies to achieve automatic and unique identification. It has been widely applied in various areas, such as access management, toll collection, and contact less payment. However, because the information transmission medium between readers and tags is radio frequency, it is easy for attackers to eavesdrop on or tamper with data. Hence, creating a secure RFID protocol is very important. In 2012, Cho et al. proposed a hash-based RFID authentication protocol for defense against brute-force attacks. Unfortunately, we find that their protocol is vulnerable to DoS and replay attacks and two design weaknesses about privacy and the authentication procedure. To enhance security, we propose an improvement that conforms to the Electronic Product Code (EPC) Class 1 Generation 2 standard for passive tags. The analyses demonstrate that our protocol can defend against security threats existing in RFID systems and is more applicable for low-cost RFID tags.

A new catalyst is developed for the asymmetric Michael addition of cyclohexanone and acetone to nitroolefins giving the corresponding nitroolefins with high enantioselectivities.

Intrinsically photosensitive retinal ganglion cells (ipRGCs) are involved in circadian and other non-image forming visual responses. An open question is whether the activity of these neurons may also be under the regulation mediated by the neurohormone melatonin. In the present work, by double-staining immunohistochemical technique, we studied the expression of MT1 and MT2, two known subtypes of mammalian melatonin receptors, in rat ipRGCs. A single subset of retinal ganglion cells labeled by the specific antibody against melanopsin exhibited the morphology typical of M1-type ipRGCs. Immunoreactivity for both MT1 and MT2 receptors was clearly seen in the cytoplasm of all labeled ipRGCs, indicating that these two receptors were co-expressed in each of these neurons. Furthermore, labeling for both the receptors were found in neonatal M1 cells as early as the day of birth. It is therefore highly plausible that retinal melatonin may directly modulate the activity of ipRGCs, thus regulating non-image forming visual functions.

Cancers exhibiting epithelial-mesenchymal transition (EMT) are associated with aggressive behavior and increased metastatic potential. Therapies that are able to target EMT would have significant clinical value. Nectin-1 is a cell surface herpes simplex virus type 1 (HSV-1) receptor that also forms a component of intercellular adherens junctions, which are typically disrupted in EMT. To explore relationships between HSV-1 sensitivity and EMT, we generated cell lines with a stable EMT phenotype from human follicular thyroid cancer (WRO82-1) through E-cadherin silencing with short hairpin RNA (shEcadWRO). HSV-1 viral attachment and gene expression were both enhanced in shEcadWRO as compared with shControl. Immunoblotting and immunostaining revealed enhanced nectin-1 expression by shEcadWRO. Receptor-blocking assays demonstrated that increased herpesviral entry into shEcadWRO as compared with shControl was mediated predominantly through nectin-1. Colocalization of green fluorescent protein-tagged HSV-1 and tdTomato-tagged nectin-1 confirmed an increase in viral attachment to nectin-1 in shEcadWRO. Cell viability assays demonstrated increased susceptibility of shEcadWRO to HSV-1 oncolysis, and a murine flank tumor model showed significantly enhanced regression of shEcadWRO tumors in response to oncolytic HSV-1 as compared with control tumors. A separate model of EMT induction through transforming growth factor-β stimulation confirmed enhanced HSV-1 susceptibility in Panc1 cells. These results demonstrate that the process of EMT leads to increased herpesviral susceptibility through enhanced cell surface nectin-1 expression, suggesting that cancers exhibiting EMT may be naturally sensitive targets for herpesviral therapy.

A chiral nickel complexes-catalyzed enantioselective Michael addition of 1,3-dicarbonyl compounds to 3-nitro-2H-chromenes has been developed; the products could be obtained in high yields and good enantioselectivities.

The meiotic division in oocytes is arrested in the G2 phase of the cell cycle. Resumption of meiosis, also known as oocyte maturation, entails a G2 to M transition. At the G2-M boundary, maturation promoting factor (MPF) activation is usually induced via several ways, including tyrosine dephosphorylation of p34(cdc2) and synthesis of cyclin B according to cell type and species. Previous studies in our laboratory demonstrated that glucocorticoids directly inhibit the meiotic maturation of pig oocytes in vitro. The aim of this study was therefore to investigate the influence of glucocorticoids on the expression of p34(cdc2) and cyclin B1 in resumption of meiosis of pig oocytes. We detected the relative levels and association of p34(cdc2) and cyclin B1. Isolated cumulus-enclosed oocytes were cultured in Waymouth MB752/1 medium supplemented with sodium pyruvate (50 microgram/ml), LH (0.5 microgram/ml), FSH (0.5 microgram/ml), and estradiol-17beta (1 microgram/ml) in the presence or absence of dexamethasone (DEX) for 24 hr; they then were cultured without hormonal supplements in the presence or absence of DEX for an additional 24 hr. We found that cyclin B1, as well as p34(cdc2), was already present in fully grown G2-arrested pig oocytes when removed from the follicle. In these oocytes, cyclin B1 and p34(cdc2) were already associated in complex. Treatment with DEX at concentrations of 1 microgram/ml or above decreased the level of cyclin B1, but had no effect on the level of p34(cdc2). The exposure of oocytes to DEX also decreased the amount of complexed p34(cdc2)-cyclin B1. These findings suggest that the inhibitory action of DEX on meiotic maturation could be due, at least in part, to the reduced amount of p34(cdc2)-cyclin B1 complex.

A novel efficient, cost-effective and solvent-free vinylogous Mannich reaction of dicyanoalkylidenes with α-amido sulfones catalyzed by potassium carbonate has been accomplished under ultrasound irradiation at room temperature. This method has advantages such as mild condition, high yields, shorter reaction time, easy work-up, and less toxic.

The aim of this study was to assess the possible role of glucocorticoids in the maturation of pig oocytes and their subsequent fertilizing capacity in vitro. Pig cumulus-enclosed oocytes collected from prepubertal gilts were cultured in Waymouth MB752/1 medium supplemented with sodium pyruvate (50 microg/ml), LH (0.5 microg/ml), FSH (0.5 microg/ml), and estradiol-17beta (1 microg/ml) in the presence or absence of cortisol or dexamethasone (DEX) for 24 h; they then were cultured without hormonal supplements in the presence or absence of cortisol or DEX for an additional 16-24 h. Treatment of cumulus-enclosed or denuded oocytes with increasing concentrations of cortisol or DEX for 48 h resulted in a dose-response inhibition of germinal vesicle breakdown (GVB). Increasing duration (12-48 h) of treatment with DEX (10 microg/ml) led to a time-dependent inhibition of GVB, which achieved statistical significance by 12 h. The addition of DEX (10 microg/ml) to maturation medium immediately after culture or at 12 h, 24 h, or 36 h after culture also decreased the percentage of oocytes with GVB. When oocytes were exposed to DEX for 48 h, the maturation rate was reduced. The degree of this reduction was dependent on DEX, and a concentration of DEX higher than 0.1 microg/ml was needed. The inhibitory effect of DEX on the maturation of oocytes was prevented by the glucocorticoid receptor antagonist RU-486. Exposure of oocytes to DEX for 40 h did not prevent sperm penetration, affect the incidence of polyspermy, or decrease the ability of oocytes to form a male pronucleus. The intracellular concentration of glutathione (GSH) in cumulus-enclosed oocytes was 4.4 mM per oocyte. Exposure of oocytes to DEX (0.01-10 microg/ml) had no effect on GSH concentration. These results demonstrate that glucocorticoids directly inhibit the meiotic but not cytoplasmic maturation of pig oocytes in vitro. This inhibitory effect is not mediated through a decrease in the level of intracellular GSH.

Ammonium chloride is a very inexpensive and readily available reagent, and efficiently catalyzes the thia-Michael addition reaction of thiols to different α-enone Michael acceptors in water. Reasonable to good yields of the desired products were obtained in most cases.

A novel efficient and simple protocol to the synthesis of norbornyl ester and ether derivatives catalyzed by In(OTf)3 under solvent-free conditions is described. This method provides several advantages such as being environmentally friendly, processing high yields and simple work-up procedure.

The multisubunit TFIID plays a direct role in transcription initiation by binding to core promoter elements and directing preinitiation complex assembly. Although TFIID may also function as a coactivator through direct interactions with promoter-bound activators, mechanistic aspects of this poorly defined function remain unclear. Here, biochemical studies show a direct TFIID–E-protein interaction that (1) is mediated through interaction of a novel E-protein activation domain (activation domain 3 [AD3]) with the TAF homology (TAFH) domain of TAF4, (2) is critical for activation of a natural target gene by an E protein, and (3) mechanistically acts by enhancing TFIID binding to the core promoter. Complementary assays establish a gene-specific role for the TAFH domain in TFIID recruitment and activation of a large subset of genes in vivo. These results firmly establish TAF4 as a bona fide E-protein coactivator as well as a mechanism involving facilitated TFIID binding through direct interaction with an E-protein activation domain.

The title chiral amino alcohol 6 was prepared from (s)-3-(2,5-dimethylphenyl)-alanine methyl ester hydrochloride by its reaction with phenyl magnesium bromide. In the presence of 2 mol% of 6, the borane reduction of prochiral ketones gave optically active secondary alcohols in high yields with the ee's ranged from 40.5 to 100%.

A new chiral β-amino alcohol, (s)-2-amino-1, 1-diphenyl-3-(2-naphthyl)-1-propanol and its use as a catalyst in the enantioselective reduction of prochiral ketones with borane were described.

Genetic lesions such as BCR–ABL1, E2A–PBX1, and MLL rearrangements (MLLr) are associated with unfavorable outcomes in adult B-cell precursor acute lymphoblastic leukemia (B-ALL). Leukemia oncoproteins may directly or indirectly disrupt cytosine methylation patterning to mediate the malignant phenotype. We postulated that DNA methylation signatures in these aggressive B-ALLs would point toward disease mechanisms and useful biomarkers and therapeutic targets. We therefore conducted DNA methylation and gene expression profiling on a cohort of 215 adult patients with B-ALL enrolled in a single phase III clinical trial (ECOG E2993) and normal control B cells. In BCR–ABL1-positive B-ALLs, aberrant cytosine methylation patterning centered around a cytokine network defined by hypomethylation and overexpression of IL2RA(CD25). The E2993 trial clinical data showed that CD25 expression was strongly associated with a poor outcome in patients with ALL regardless of BCR–ABL1 status, suggesting CD25 as a novel prognostic biomarker for risk stratification in B-ALLs. In E2A–PBX1-positive B-ALLs, aberrant DNA methylation patterning was strongly associated with direct fusion protein binding as shown by the E2A–PBX1 chromatin immunoprecipitation (ChIP) sequencing (ChIP-seq), suggesting that E2A–PBX1 fusion protein directly remodels the epigenome to impose an aggressive B-ALL phenotype. MLLr B-ALL featured prominent cytosine hypomethylation, which was linked with MLL fusion protein binding, H3K79 dimethylation, and transcriptional upregulation, affecting a set of known and newly identified MLL fusion direct targets with oncogenic activity such as FLT3 and BCL6. Notably, BCL6 blockade or loss of function suppressed proliferation and survival of MLLr leukemia cells, suggesting BCL6-targeted therapy as a new therapeutic strategy for MLLr B-ALLs. Significance: We conducted the first integrative epigenomic study in adult B-ALLs, as a correlative study to the ECOG E2993 phase III clinical trial. This study links for the first time the direct actions of oncogenic fusion proteins with disruption of epigenetic regulation mediated by cytosine methylation. We identify a novel clinically actionable biomarker in B-ALLs: IL2RA(CD25), which is linked with BCR–ABL1 and an inflammatory signaling network associated with chemotherapy resistance. We show that BCL6 is a novel MLL fusion protein target that is required to maintain the proliferation and survival of primary human adult MLLr cells and provide the basis for a clinical trial with BCL6 inhibitors for patients with MLLr. Cancer Discov; 2(11); 1004–23. ©2012 AACR. Read the Commentary on this article by Cimmino and Aifantis, p. 976. This article is highlighted in the In This Issue feature, p. 961

The 1:1 mixture of a quinidine-derived thiourea and L-proline can catalyze direct vinylogous Michael reactions of nitroolefins with alkylidenemalononitriles in absolute diastereo- and high enantioselectivities.

To determine changes in expression of transforming growth factor β-2 (TGF-β2) and basic fibroblast growth factor (bFGF) in scleral desmocytes from anterior and posterior portions of experimentally-induced myopic eyes of guinea pigs.Three groups (n = 10) of 2-week-old guinea pigs were used to develop concave lens-induced myopia (LIM) in one eye via the out-of-focus method for 6, 15, or 30 days respectively, while the other eye in each guinea pig served as the self-control (SC). After myopia induction, lenses were removed, and scleral fibroblasts were cultured and passaged twice. TGF-β2 and bFGF expression levels of scleral desmocytes in LIM and SC groups were compared by immunocytochemistry, quantitative real-time PCR (qRT-PCR) and Western blot analyses.The TGF-β2 expression of the anterior portion of the sclera in the LIM group was significantly higher at 15 days, and at its highest at 30 days after myopia induction compared with the SC group (P0.05). The TGF-β2 staining of the posterior sclera in the LIM group began to rise significantly at 6 days, peaked at 15 days and remained significantly higher than that of the anterior part, as well as the SC group, even at 30 days after myopia induction (P0.05). BFGF levels in scleral desmocytes from the anterior and posterior regions in the LIM group were both significantly lower than those of the SC group at all time points after myopia induction (P0.05). Furthermore, as the myopia progressed, bFGF expression in the anterior and posterior sclera in the LIM group gradually and statistically significantly decreased compared with the SC group (P0.05); however, no significant differences were observed between the anterior and posterior parts in the LIM group at any time after myopia induction (P0.05). All these results were consistent at the mRNA and protein levels.During myopia development in lens-induced guinea pigs, the increase in TGF-β2 activity of scleral desmocytes initiated at the posterior pole. Along with the induction time, the TGF-β2 activity in all scleral desmocytes became elevated. By contrast, the bFGF activity showed a general decline in all scleral desmocytes, rather than mainly in the posterior pole. These results imply that expression of TGF-β2 in scleral desmocytes plays a direct role, while that of bFGF exerts an indirect role in myopia development.

Steroidogenic Factor 1 (SF-1, Ad4bp, NR5A1) is a nuclear receptor expressed mainly in the adrenals and gonads. It activates the transcription of genes in steroidogenesis, reproduction, and energy metabolism. In addition, it also regulates the growth and differentiation of adrenogonadal primodial cells. SF-1 resides in the nucleus and the centrosome. SF-1 moves dynamically in the nucleus, and SF-1 location and activity are dynamically regulated by post-translational modifications. In the centrosome, SF-1 maintains genomic integrity by controlling centrosome homeostasis. SF-1 prevents centrosome amplification by restricting aberrant activation of centrosomal DNA-PK. Upon SF-1 removal, DNA-PK is activated and centrosomes are amplified. This leads to genomic instability and cell growth defects. These data indicate that SF-1 at both the nucleus and the centrosome contributes to cell growth control, but the mechanisms of SF-1 action in different locations are different.

The mechanical microenvironment of the chondrocytes plays an important role in cartilage homeostasis and in the health of the joint. The pericellular matrix, cellular membrane of the chondrocytes, and their cytoskeletal structures are key elements in the mechanical environment. The aims of this study are to measure the viscoelastic properties of isolated chondrons and chondrocytes from rabbit knee cartilage using micropipette aspiration and to determine the effect of aging on these properties.Three age groups of rabbit knees were evaluated: (1) young (2 months, n = 10); (2) adult (8 months, n = 10); and (3) old (31 months, n = 10). Chondrocytes were isolated from the right knee cartilage and chondrons were isolated from left knees using enzymatic methods. Micropipette aspiration combined with a standard linear viscoelastic solid model was used to quantify changes in the viscoelastic properties of chondrons and chondrocytes within 2 hours of isolation. The morphology and structure of isolated chondrons were evaluated by optical microscope using hematoxylin and eosin staining and collagen-6 immunofluorescence staining.In response to an applied constant 0.3 - 0.4 kPa of negative pressure, all chondrocytes exhibited standard linear viscoelastic solid properties. Model predictions of the creep data showed that the average equilibrium modulus (E(∞)), instantaneous modulus (E(0)), and apparent viscosity (m) of old chondrocytes was significantly lower than the young and adult chondrocytes (P0.001); however, no difference was found between young and adult chondrocytes (P0.05). The adult and old chondrons generally possessed a thicker pericellular matrix (PCM) with more enclosed cells. The young and adult chondrons exhibited the same viscoelastic creep behavior under a greater applied pressure (1.0 - 1.1 kPa) without the deformation seen in the old chondrons. The viscoelastic properties (E(∞), E(0), and m) of young and adult chondrons were significantly greater than that observed in young and adult cells, respectively (P0.001). The adult chondrons were stiffer than the young chondrons under micropipette aspiration (P0.001).Our findings provide a theoretical model to measure the viscoelastic properties of the chondrons as a whole unit by micropipette aspiration, and further suggest that the properties of the chondrocytes and PCM have an important influence on the biomechanical microenvironment of the knee joint cartilage degeneration that occurs with aging.

SummaryThe H3K4me3 mark in chromatin is closely correlated with actively transcribed genes, although the mechanisms involved in its generation and function are not fully understood. In vitro studies with recombinant chromatin and purified human factors demonstrate a robust SET1 complex (SET1C)-mediated H3K4 trimethylation that is dependent upon p53- and p300-mediated H3 acetylation, a corresponding SET1C-mediated enhancement of p53- and p300-dependent transcription that reflects a primary effect of SET1C through H3K4 trimethylation, and direct SET1C-p53 and SET1C-p300 interactions indicative of a targeted recruitment mechanism. Complementary cell-based assays demonstrate a DNA-damage-induced p53-SET1C interaction, a corresponding enrichment of SET1C and H3K4me3 on a p53 target gene (p21/WAF1), and a corresponding codependency of H3K4 trimethylation and transcription upon p300 and SET1C. These results establish a mechanism in which SET1C and p300 act cooperatively, through direct interactions and coupled histone modifications, to facilitate the function of p53.

SF-1 (Steroidogenic Factor 1, NR5A1) is a tissue-specific transcription factor critical for the growth, development and differentiation of steroidogenic and a few other endocrine tissues. But how SF-1 regulates cell growth is not entirely clear. Here we found that SF-1 was localized to the centrosome in addition to the nucleus, and SF-1 depletion by shRNA caused centrosome over-duplication, aberrant mitosis and genomic instability, leading to a reduction of cell number. Centrosome amplification defect was rescued by both wild-type SF-1 and transcription-defective SF-1-G35E, suggesting a non-genomic activity of SF-1 involved in centrosome homeostasis. In addition, we identified in SF-1 a centrosome localization signal, whose overexpression led to reduced localization of both SF-1 and γ-tubulin to the centrosome. Our results uncover a novel role of SF-1 in the control of centrosome homeostasis and genomic stability.

The scheduling problem of maintenance work on the equipment support station influences the support efficiency, especially for a station which repairs a large number of failed items from more than one subordinate operating station. The influence of the mean time to repair (MTTR) on system availability was analyzed for maintenance stations, then the factors which determine the maintenance priority of a failed item were modeled, including the demand of the subordinate station, time and maintenance resource to repair the item. Then a scheduling algorithm of maintenance work on equipment support station based on dynamic maintenance priority was proposed. The algorithm was used in an case, and the result shows that comparing to FIFO (first in, first out) method and resource fitting method, the algorithm improves the support efficiency by much while cutting down the demand for maintenance resources.

Dynamically tuned gyroscope (DTG) is used more and more wildly in inertial navigator, so it is significant to eliminate the gyro random drift and noise in order to increase the precise of the DTG. The DTG error characteristics and mathematic model were presented, a fast algorithm based on translation invariant discrete wavelet transform (TIDWT) was used with a new thresholding function, the signal sampled in dynamic disturbance are processed by this method, and the validity is verified through a experiment.

The addition of dialkylmalonates is optimal under conditions A) and proceeds with complete anti diastereoselectivity and excellent enantioselectivity.

A new chiral β-amino alcohol, (s)-2-amino-1, 1-diphenyl-3-(2-naphthyl)-1-propanol and its use as a catalyst in the enantioselective reduction of prochiral ketones with borane were described.

To fully demonstrate the alterations about the viscoelastic properties of chondrocytes in rabbit knee articular cartilage.Fifteen New Zealand white rabbits were divided into 3 age groups: young group (1 month), adult group (8 months) and old group (31 months). All rabbits were sacrificed and isolated from knee joint and digested into chondrocytes. The micropipette aspiration combined with Half-space model was used to quantify changes in viscoelastic properties of chondrocytes.Experimental studies have shown that the changes of aspiration length with time in old group were obviously different from young group and adult group. But similar variations were found between the latter two groups. The viscoelastic properties of chondrocytes in old group exhibited a significantly lower instantaneous modulus E0 (0.55 +/- 0.05 kPa), equilibrium modulus E infinity (0.28 +/- 0.04 kPa) and apparent viscosity micro (4.10 +/- 0.61 kPa x s) as compared with young group (0.67 +/- 0.10), (0.37 +/- 0.09), (6.29 +/- 0.92) kPa x s (P0.001) versus adult group: (0.65 +/- 0.07), (0.35 +/- 0.05), (6.01 +/- 0.89) kPa x s (P0.001). But no difference were found between the latter two groups (P0.05).In response to a step pressure, chondrocytes in each group exhibited the viscoelastic solid creep behavior. The viscoelastic properties of chondrocytes markedly decreased in old group.

To assess the biomechanical stability of asymmetrical posterior internal fixation for transforaminal lumbar interbody fusion (TLIF) with transfacetopedicular screws (TFPS).Range of motion (ROM) testing was performed in 7 fresh-frozen human cadaveric lumbar spine motion segments in flexion/extension, lateral bending, and axial rotation using 10.0 Nm torques at the L3-4 motion segment. The sequential test configurations included intact motion segment, TLIF and ipsilateral pedicle screw (PS), TLIF and ipsilateral PS plus contralateral TFPS according to Boucher technique, and TLIF and bilateral PS. The ROM was determined to assess the construct stability.In flexion/extension, lateral bending, and axial rotation, no measureable difference was found in the ROM between the standard bilateral pedicle screw and the novel asymmetric posterior internal fixation after TLIF. After TLIF, the ipsilateral PS construct provided less segment stability than the novel asymmetric construct with TFPS in flexion, left bending and left rotation. In rotation, the novel asymmetric construct allowed for significant off-axial rotation motions detrimental to the stability and fusion.Ipsilateral PS placement plus contralateral TFPS provides stability comparable to that of TLIF with bilateral PS, and can be an alternative in minimal invasive surgery.

Three‐component Mannich‐type reaction of aldehydes, aromatic amines, and silyl enolate proceeded smoothly to afford β‐amino carbonyl compounds with good yields in the presence of a catalytic amount of HBF4‐SiO2.

To evaluate the short-term outcome of patients receiving metal-on-mental hip resurfacing arthroplasty and analyze the factors affecting the result.In 13 patients receiving metal-on-metal hip resurfacing arthroplasties with scheduled follow-up, the treatment outcomes were assessed according to the Harris Hip Score.The short-term outcomes of hip resurfacing arthroplasties were encouraging, and intraoperative complications, infections, peripheral nerve palsy, hip dislocations or clinically overt lower limb deep vein thrombosis occurred in none of these cases. All the patients reported complete or major pain relief. Clinical assessment according to the Harris Hip Score revealed an improvement from an average score of 36.69 preoperatively to 89.63 after the surgery. Crutch use lasted for a maximum of 4 weeks postoperatively in these patients, after which the patients were all capable of walking without crutches with full weight-bearing.

To measure the mechanical properties of chondrocytes of articular cartilage of knee in order to provide relevant technical parameters into the development of cartilage tissue engineering.Eight NZW rabbits were killed, and their bilateral knee joints were taken out. The articular cartilage of the left knees were used for histological study, and articular cartilage of the right knees was digested with 0.4% pronase and 0.025% collagenase type II so as to make isolation of chondrocytes. The viability rate of the isolated chondrocytes was detected by trypan blue staining. The diameters of the chondrocytes in the histological sections and single cell suspension were measured respectively. The mechanical properties of the chondrocytes were determined using micropipette aspiration technique coupled with half-space model.In the normal articular cartilage 4 structural zones were differentiated: tangential, transitional, radial, and calcified zones. The viability rate of chondrocytes was 98.2% on average after isolation. The mean diameter of the chondrocytes in the histological sections was (14.2+/-2.9) microm, not significantly different from that in the single cell suspension [(14.9+/-2.2) microm, t=1.31, P=0.19]. In response to a prescribed pressure, the chondrocytes exhibited viscoelastic solid creep behavior characterized initially by a jump in displacement followed by a monotonically decreasing rate of deformation that generally reached an equilibrium displacement. The cells were observed to deform to a length of as much as three times the radius of the micropipette without completely entering the micropipette. The cells were then extruded from the micropipette and completely recovered. The Young's modulus of the normal chondrocytes was (0.57+/-0.43) kPa, and the k1, k2, and micro of the viscoelastic parameters were (0.37+/-0.07) kPa, (0.29+/-0.04) kPa, and (6.36+/-1.12) kPa-s respectively. The k1 is positively correlated to the cell diameter (r=0.4, P=0.031).Chondrocytes from normal articular cartilage behave as a viscoelastic solid. Micropipette aspiration technique is an efficient method for the study of chondrocyte biomechanics.

(S)-(1-Benzylpyrrolidin-2-yl)diphenylmethanol and cinchonine were evaluated as promotors in the asymmetric additions of phenylacetylene to ketones, in order to prepare chiral propargylic alcohols. Good yields (up to 89%) and moderate enantioselectivities (up to 77.9% ee) were achieved. Addition of Ti(OPr-i)4 can significantly improve the enantioselectivity of the reaction.

A simple and efficient method has been developed for the synthesis of α-aminonitriles by a one-pot three-component condensation of aldehydes, amines, and trimethylsilyl cyanide in the presence of a catalytic amount of silica sulfuric acid at room temperature. The silica sulfuric acid is reusable and could be applied in subsequent reactions with comparable activity.

Steroidogenic factor 1 (SF-1) is a nuclear receptor essential for steroidogenic gene expression, but how its activity is regulated is unclear. Here we demonstrate that p300 plays an important role in regulating SF-1 function. SF-1 was acetylated in vitro and in vivo by p300 at the KQQKK motif in the Ftz-F1 (Fushi-tarazu factor 1) box adjacent to its DNA-binding domain. Mutation of the KQQKK motif reduced the DNA-binding activity and p300-dependent activation of SF-1. When stimulated with cyclic AMP (cAMP), adrenocortical Y1 cells expressed more p300, leading to additional SF-1 association with p300 and increased SF-1 acetylation and DNA binding. It also increased SF-1 colocalization with p300 in nuclear foci. Collectively, these results indicate that SF-1 transcriptional activity is regulated by p300 in response to the cAMP signaling pathway by way of increased acetylation, DNA binding, and recruitment to nuclear foci.

2,3-Dihydro-1H-1,5-benzodiazepines have been synthesized from o-phenylenediamine (OPDA) and ketones under solvent-free conditions in the presence of a catalytic amount of molecular iodine. All of the ketones, including cyclic ketones and acyclic ketones, reacted smoothly with OPDA to furnish products. Compared to other reaction conditions, this new protocol has the advantage of excellent yield and short reaction time at room temperature.