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Apoptin can specifically kill cancer cells but has no toxicity to normal cells. Human telomerase reverse transcriptase (hTERT) can act as a tumour‐specific promoter by triggering the expression of certain genes in tumour cells. This study aims to investigate the inhibitory effects and to explore the inhibitory pathway of a dual cancer‐specific recombinant adenovirus (Ad‐apoptin‐hTERTp‐E1a, Ad‐VT) on breast cancer stem cells. Breast cancer cell spheres were obtained from MCF‐7 cells through serum‐free suspension culture. The cell spheres were detected by flow cytometry for CD44+ CD24− cell subsets. The stemness of MCF‐7‐CSC cells was confirmed by in vivo tumorigenesis experiments. The inhibitory effect of the recombinant adenoviruses on MCF‐7‐CSC cells was evaluated by CCK‐8 assay. In addition, the stemness of adenovirus‐infected MCF‐7‐CSC cells was analysed by testing the presence of CD44+ CD24− cell subsets. The ability of the recombinant adenovirus to induce MCF‐7‐CSC cell apoptosis was detected by staining JC‐1, TMRM and Annexin V. Our results showed that a significantly higher proportion of the CD44+ CD24− cell subsets was present in MCF‐7‐CSC cells with a significantly increased expression of stem cell marker proteins. The MCF‐7‐CSC cells, whlist exhibited a strong tumorigenic ability with a certain degree of stemness in mice, were shown to be strongly inhibited by recombinant adenovirus Ad‐VT through cell apoptosis. In addition, Ad‐VT was shown to exert a killing effect on BCSCs. These results provide a new theoretical basis for the future treatment of breast cancer.

Protein phosphatase 1 catalytic subunit beta (PPP1CB) is a disease-causing gene of Noonan-like syndrome, which acts via the RAS/MAPK pathway. To date, only 17 patients diagnosed with PPP1CB-related Noonan-like syndrome have been reported around the world, with few reports in Asia. Twelve reported patients are of short stature and only one patient was treated with growth hormone (GH); however, follow-up data is lacking. To the best of our knowledge, this is the first reported patient with complete recombinant human growth hormone (rhGH) treatment follow-up data; the patient has a de novo c.146C>G (p.Pro49Arg) mutation in the PPP1CB gene. The hair pattern of the patient (coarse, curly, slow growing, and fragile) combined with Noonan dysmorphic features, developmental delay, and congenital heart disease, are highly consistent with the typical features observed in Noonan syndrome-like disorder with loose anagen hair 2 (NSLH2). rhGH treatment, administered for 3 years and 8 months, promoted the patient's linear growth. Our findings expand the data regarding the treatment of short stature in patients with NSLH2 caused by PPP1CB mutation. Clinical manifestation, growth and development process, and rhGH therapy effect data will aid in future revision of the relevant diagnosis and treatment guidelines.

Using traditional high‐fidelity numerical simulation to simulate fluid flow in fractured porous media in a real field remains challenging. It involves a large number of degrees of freedom when matrix and fracture equations are solved. To address this challenge, we propose a Galerkin‐free framework to construct a reduced‐order model (ROM) based on the proper orthogonal decomposition (POD). Compared with the typical POD‐based modeling process commonly used in previous studies, the POD‐ROM can be built without performing the Galerkin projection of flow equations onto the low‐dimensional space spanned by the POD basis functions. The numerical integration method was incorporated to obtain the POD time coefficients based on the flow equations solved by the conventional finite volume method. Two complex fracture cases reflecting high‐contrast porous media in a two‐dimensional domain were designed to verify the accuracy and efficiency of the established Galerkin‐free POD‐ROM. Sensitivity analysis of parameters was conducted to examine the adaptability of the ROM. The results illustrate that, compared with the fine‐scale model, the ROM can significantly reduce the CPU time without compromising the quality of the numerical solutions.

Managing Nitrogen (N) is fundamental, yet challenging, for sustainable development: N is essential for producing crops and livestock and consequently important for food security. However, the risin...

MicroRNAs have emerged as essential regulators of various cellular processes. We identified the role and underlying mechanisms of miR-2392 in gastric cancer (GC) metastasis. MiR-2392 was down-regulated in GC cell lines and tissues, and overexpression of miR-2392 significantly inhibited GC invasion and metastasis in vitro and in vivo We identified MAML3 and WHSC1 as novel targets of miR-2392, and knockdown of MAML3 and WHSC1 had the same antimetastatic effect as that of miR-2392 in GC cells. These effects were clinically relevant, as low miR-2392 expression was correlated with high MAML3 and WHSC1 expression and poor survival in patients with GC. Furthermore, forced expression of miR-2392 substantially suppressed Slug and Twist1, transcriptional repressors of E-cadherin, by targeting MAML3 and WHSC1, respectively, resulting in inhibition of the epithelial-mesenchymal transition. These findings indicate that the miR-2392-MAML3/WHSC1-Slug/Twist1 regulatory axis plays a critical role in GC metastasis. Restoration of miR-2392 may be a therapeutic approach for blocking GC metastasis.-Li, J., Li, T., Lu, Y., Shen, G., Guo, H., Wu, J., Lei, C., Du, F., Zhou, F., Zhao, X., Nie, Y., Fan, D. MiR-2392 suppresses metastasis and epithelial-mesenchymal transition by targeting MAML3 and WHSC1 in gastric cancer.

The chromatographic chiral resolution of 4-aryl-1,4-dihydropyridines (1–32), 4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidines (33–38), and 4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidines (39–41) was studied on a tetraproline-immobilized chiral column synthesized in our lab. This tetraproline chiral stationary phase can resolve most of these compounds. The 4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidines (33–38) and 4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidines (39–41) were more efficiently resolved than the racemic 4-aryl-1,4-dihydropyridines on the tetraproline chiralstationary phase. Analytes with 5,5-dimethyl groups (39–41) were less efficiently resolved than analytes without 5,5-dimethyl substituents (1–16). The 4-aryl-2-oxo-1,2,3,4-tetrahydropyrimidines (39–41) without a sulfur atom were much more efficiently resolved than 4-aryl-2-thioxo-1,2,3,4-tetrahydropyrimidines (33–38). No obvious electronic effects on the resolution of any of these analytes (1–41) were observed on the tetraproline chiral stationary phase. The tetraproline chiral stationary phase separated enantiomers mainly via hydrogen bonding interactions. Chirality, 2013. © 2013 Wiley Periodicals, Inc.

The chromatographic chiral resolution of two new series of racemic 4-substituted-1,4-dihydropyridine derivatives was studied on a commercial Chiralpak AD-H column. Analytes without 5,5-dimethyl substituents (1–15) are more efficiently resolved than analytes with 5,5-dimethyl groups (16–30). The AD-H column discriminated between enantiomers through both hydrogen bonding attractions and π–π interactions. This interpretation is in accord with plots of the logarithm of separation factors, log(α), versus σ (Hammett–Swain substituent parameter) and σ+ (Brown substituent constant) plots. By elucidating the effects of the remote substituents on these chiral separations, it was shown that the influence of π–π interaction forces increase when steric bulk effects act to decrease the hydrogen bonding attractive forces on the AD-H column. Chirality 24:854–859, 2012. © 2012 Wiley Periodicals, Inc.

While the ability of stem cells to switch lineages has been suggested, the route(s) through which this may happen is unclear. To date, the best characterized adult stem cell population considered to possess transdifferentiation capacity is BM-MSCs (bone marrow mesenchymal stem cells). We investigated whether BM-MSCs that had terminally differentiated into the neural or epithelial lineage could be induced to transdifferentiate into the other phenotype in vitro. Our results reveal that neuronal phenotypic cells derived from adult rat bone marrow cells can be switched to epithelial phenotypic cells, or vice versa, by culture manipulation allowing the differentiated cells to go through, first, dedifferentiation and then redifferentiation to another phenotype. Direct transdifferentiation from differentiated neuronal or epithelial phenotype to the other differentiated phenotype cannot be observed even when appropriate culture conditions are provided. Thus, dedifferentiation appears to be a prerequisite for changing fate and differentiating into a different lineage from a differentiated cell population.

Mesenchymal stem cells (MSCs) can differentiate into neurons in an appropriate cellular environment. Retinoid signaling pathway is required in neural development. However, the effect and mechanism through retinoid signaling regulates neuronal differentiation of MSCs are still poorly understood. Here, we report that all-transretinoic acid (ATRA) pre-induction improved neuronal differentiation of rat MSCs. We found that, when MSCs were exposed to different concentrations of ATRA (0.01–100 lmol ⁄ L) for 24 h and then cultured with modified neuronal induction medium (MNM), 1 lmol ⁄ L ATRA pre-induction significantly improved neuronal differentiation efficiency and neural-cell survival. Compared with MNM alone induced neural-like cells, ATRA ⁄ MNM induced cells expressed higher levels of Nestin, neuron specific enolase (NSE), microtubule-associated protein-2 (MAP-2), but lower levels of CD68, glial fibrillary acidic protein (GFAP), and glial cell line-derived neurotrophic factor(GDNF), also exhibited higher resting membrane potential and intracellular calcium concentration, supporting that ATRA pre-induction promotes maturation and function of derived neurons but not neuroglia cells from MSCs. Endogenous retinoid X receptors (RXR) RXRa and RXRc (and to a lesser extent, RXRb) were weakly expressed in MSCs. But the expression of RARa and RARc was readily detectable, whereas RARb was undetectable. However, at 24 h after ATRA treatment, the expression of RARb, not RARa or RARc, increased significantly. We further found the subnuclear redistribution of RARb in differentiated neurons, suggesting that RARb may function as a major mediator of retinoid signaling during neuronal differentiation from MSCs. ATRA treatment upregulated the expression of Vimentin and Stra13, while it downregulated the expression of Brachyury in MSCs. Thus, our results demonstrate that pre-activation of retinoid signaling by ATRA facilitates neuronal differentiation of MSCs.

Scope Vitamin A (VA) is an essential nutrient for the development of the brain. We previously found that children with autism spectrum disorder (ASD) have a significant rate of VA deficiency (VAD). In the current study, we aim to determine whether VAD is a risk factor for the generation of autistic-like behaviors via the transcription factor retinoic acid receptor beta (RARβ)-regulated cluster of differentiation 38 (CD38)-oxytocin (OXT) axis. Methods and results Gestational VAD or VA supplementation (VAS) rat models are established, and the autistic-like behaviors in the offspring rats are investigated. The different expression levels of RARβ and CD38 in hypothalamic tissue and serum retinol and OXT concentration are tested. Primary cultured rat hypothalamic neurons are treated with all-trans retinoic acid (atRA), and recombinant adenoviruses carrying the rat RARβ (AdRARβ) or RNA interference virus RARβ-siRNA (siRARβ) are used to infect neurons to change RARβ signal. Western blotting, chromatin immunoprecipitation (ChIP), and intracellular Ca2+ detections are used to investigate the primary regulatory mechanism of RARβ in the CD38-OXT signaling pathway. We found that gestational VAD increases autistic-like behaviors and decreases the expression levels of hypothalamic RARβ and CD38 and serum OXT levels in the offspring. VAS ameliorates these autistic-like behaviors and increases the expression levels of RARβ, CD38, and OXT in the gestational VAD pups. In vitro, atRA increases the Ca2+ excitability of neurons, which might further promote the release of OXT. Different CD38 levels are induced in the neurons by infection with different RARβ adenoviruses. Furthermore, atRA enhances the binding of RARβ to the proximal promoter of CD38, indicating a potential upregulation of CD38 transcriptional activity by RARβ. Conclusions Gestational VAD might be a risk factor for autistic-like behaviors due to the RARβ signal suppression of CD38 expression in the hypothalamus of the offspring, which improves with VAS during the early-life period. The nutritional status during pregnancy and the early-life period is important in rats.

The application of peptide and peptidomimetic chiral selectors in LC is reviewed in this article. In particular, methods for finding these types of selectors using combinatorial library approaches are discussed, as well as recent advances in the use of peptides and peptidomimetics as general chiral selectors for LC. In terms of the library approaches, batch screening and reciprocal screening are discussed. As for general chiral selectors, one example involves the application of chiral diamide phases. Another example shows the versatility of oligoproline chiral stationary phases, which exhibit resolution for a number of racemic analytes, comparable to other well-established chiral stationary phases.

A method to screen combinatorial libraries for the development of selective ligands for protein affinity chromatographic purification is described. The method is based on the application of parallel combinatorial libraries, and it has several potential advantages. The screening procedure is simple and straightforward, and it does not require the chemical derivatization of the target proteins or even that the target protein be pure. The experiment can also be designed to select binders that are less likely to cause protein denaturation. Feasibility of this approach is demonstrated with a model study of the chromatographic purification of bovine albumin serum (BSA) and Avidin.

MSCs have been shown to improve functional and pathological outcome in lung fibrosis. However, low in vivo cell engraftment of the transplanted cells limits their overall effectiveness. KGF (also known as FGF-7) is a critical mediator of pulmonary epithelial repair through stimulation of epithelial cell proliferation. However, the role of KGF in MSCs and its therapeutic effects have not been identified. In this study, we investigated the effect of KGF on MSCs and its preventive role in hyperoxia-induced fibrosis in neonatal rats. Neonatal rats exposed to normoxia or hyperoxia were randomly assigned to receive intraperitoneal injections of normal saline (PL), MSCs, or KGF pretreated MSCs on the fourth day of exposure. Our results showed that as compared to PL, while MSCs attenuated lung fibrosis, KGF pretreated MSCs exhibited enhanced preventive effect against lung fibrosis. This effect was partly attributed to enhanced mobilization of MSCs to the fibrotic lungs. In addition, the SHH signaling pathway, which is associated with the differentiation of stem cells was activated by KGF. Our data suggest that MSCs, especially KGF preconditioned MSCs, can attenuate lung fibrosis and KGF may regulate the MSCs behavior by activating SHH pathway.