An Organo-Palladium Host Built from a Dynamic Macrocyclic Ligand: Adaptive Self-Assembly, Induced-Fit Guest Binding, and Catalysis.

Artificial hosts with rich conformational dynamics are attractive to supramolecular chemists due to their adaptive guest-binding properties and enzyme-like catalytic functions. We report here the adaptive self-assembly and host-guest catalysis of a new water-soluble organo-palladium host (Pd2 L2 ) built from a pyridinium-bonded macrocyclic ligand (L) and cis-blocked palladium corners (Pd). While the direct self-assembly of L with Pd gives rise to a dynamic mixture of products, both neutral polyaromatic hydrocarbons and an anionic polyoxometalate cluster (W10 O32 4- ) can template the dominant formation of the Pd2 L2 host. Guest-adaptive conformational changes and induced-fit cavity deformation of the Pd2 L2 host have been clearly observed in the crystal structures. Moreover, the installation of the electron-rich W10 O32 4- cluster within the cationic redox-active host (W10 O32 ⊂Pd2 L2 ) facilitates the efficient and selective C-H photooxidation of toluene derivatives to aldehyde products under mild conditions, thus representing an ideal platform for green supramolecular catalysis.

[Research progress of histone deacetylase 6 inhibitors in the therapy of ischemic stroke].

The protein acetylation by histone acetyltransferases (HATs) and histone deacetylases (HDACs) plays a significant role in the development and maturation of the nervous system. HDAC6, belonging to class II HDACs, by regulating the survival, differentiation and maturation of neural cells, plays an important role in the development of the nervous system and participates in multiple pathological processes of cerebral ischemic injury. In addition, HDAC6 participates in the regulation of cognition and emotion of the brain. This article summarized the latest research results in recent years and expounded that HDAC6 inhibitors could produce a positive and effective neuroprotective effect on ischemic stroke by reducing the neuronal damage induced by excitotoxicity and oxidative stress, depressing the release of inflammatory mediators, inhibiting the apoptosis of neurons and promoting the growth of nerve and blood vessel.

[Preparation and in vitro study on diffusion of capsaicin cubosome].

This study was to investigate the permeability and absorbability of capsaicin cubosome across abdominal skin of the SD rats in vitro. Diffusion of capsaicin cubosome and cream was performed with the modified Franz diffusion cell technique. The capsaicin cubosome showed no enhancement of skin permeation within 24 hours. However, the deposition amounts of capsaicin in the rat skin in the cubosome group was markedly higher than those in the commercial cream group (P < 0.01). Cubosome showed excellent characetristic of skin-targed which could be a good carrier for the local transdermal drug delivery system.

A Pd4L2 cage containing Brønsted-base active sites for the one-pot photooxidation/Knoevenagel condensation reaction.

Brønsted-base active sites on a Pd4L2 cage facilitates enhanced catalytic efficiency, wide substrate scope and high turnover number (TON) for the one-pot photooxidation/Knoevenagel condensation reaction under mild conditions.

Choroid Plexus Enlargement and Allostatic Load in Schizophrenia.

Although schizophrenia is a brain disorder, increasing evidence suggests that there may be body-wide involvement in this illness. However, direct evidence of brain structures involved in the presumed peripheral-central interaction in schizophrenia is still unclear. Seventy-nine previously treatment-naïve first-episode schizophrenia patients who were within 2-week antipsychotics initial stabilization, and 41 age- and sex-matched healthy controls were enrolled in the study. Group differences in subcortical brain regional structures measured by MRI and the subclinical cardiovascular, metabolic, immune, and neuroendocrine biomarkers as indexed by allostatic load, and their associations were explored. Compared with controls, patients with schizophrenia had significantly higher allostatic load (P = .001). Lateral ventricle (P < .001), choroid plexus (P < .001), and thalamus volumes (P < .001) were significantly larger, whereas amygdala volume (P = .001) was significantly smaller in patients. The choroid plexus alone was significantly correlated with higher allostatic load after age, sex, education level, and the total intracranial volume were taken into account (t = 3.60, P < .001). Allostatic load was also significantly correlated with PANSS positive (r = 0.28, P = .016) and negative (r = -0.31, P = .008) symptoms, but in opposite directions. The peripheral multisystemic and central nervous system abnormalities in schizophrenia may interact through the choroid plexus during the early stage of the illness. The choroid plexus might provide a sensitive structural biomarker to study the treatment and prevention of brain-periphery interaction abnormalities in schizophrenia.

Novel TPD-based organic D-pi-A dyes for dye-sensitized solar cells.

A novel class of organic D-pi-A dyes employing a N,N,N',N'-tetraphenylbenzidine (TPD) unit as donor was designed and synthesized for dye-sensitized solar cells, which achieved a solar-to-electricity conversion efficiency (eta) of 5.63% in preliminary tests as compared to 6.42% for N3 dye under the same experimental conditions.

Low-dose tubacin promotes BMSCs proliferation and morphological changes through the ERK pathway.

Histone deacetylase 6 (HDAC6) plays critical roles in many cellular processes related to cancer, but its epigenetic regulation in bone marrow stromal stem cells (BMSCs) remains unexplored. This study investigated the beneficial effects of Tubulin Acetylation Inducer (tubacin), a novel specific HDAC6 inhibitor, on the proliferation and migration of BMSCs. A low concentration of tubacin promoted BMSC commitment and enhanced proliferation of BMSCs. Atomic force microscopy results showed that tubacin induced morphological changes and enhanced the mechanical properties of BMSCs. Furthermore, low tubacin concentrations significantly upregulated protein expression of acetylated α-tubulin, VCAM-1, and ICAM-1, which could be suppressed by an ERK inhibitor. Protein chip analysis showed that there were significant changes in the expression levels of 49 cytokines after tubacin treatment, which participate in inflammatory responses and cell activation, proliferation, and differentiation. Our findings suggest that the protective effects of tubacin on BMSCs involve HDAC6 inhibition by activating the ERK pathway.

Development of a HPLC Method for the Quantitative Determination of Capsaicin in Collagen Sponge.

Controlling the concentration of drugs in pharmaceutical products is essential to patient's safety. In this study, a simple and sensitive HPLC method is developed to quantitatively analyze capsaicin in collagen sponge. The capsaicin from sponge was extracted for 30 min with ultrasonic wave extraction technique and methanol was used as solvent. The chromatographic method was performed by using isocratic system composed of acetonitrile-water (70 : 30) with a flow rate of 1 mL/min and the detection wavelength was at 280 nm. Capsaicin can be successfully separated with good linearity (the regression equation is A = 9.7182C + 0.8547; R (2) = 1.0) and perfect recovery (99.72%). The mean capsaicin concentration in collagen sponge was 49.32 mg/g (RSD = 1.30%; n = 3). In conclusion, the ultrasonic wave extraction method is simple and the extracting efficiency is high. The HPLC assay has excellent sensitivity and specificity and is a convenient method for capsaicin detection in collagen sponge. This paper firstly discusses the quantitative analysis of capsaicin in collagen sponge.

[The expression and significance of CD151 in pituitary adenomas].

OBJECTIVE: To investigate the expression and significance of CD151 in pituitary adenomas. METHODS: Thirty-six pituitary adenomas were collected immediately after surgery together with five normal pituitary tissue. Real time-PCR, Western blot and immunohistochemistry analysis were performed to detect the expression of CD151 mRNA and protein in thirty-six pituitary adenomases and five normal pituitary tissues. RESULTS: The expression of CD151 in all pituitary adenomases was observed to be significantly higher than that in normal pituitary tissues by Western blot, real time PCR, and immunohistochemistry analysis (P < 0.01). The expression levels of protein and mRNA in invasive pituitary adenomas were much higher than those in non-invasive pituitary adenomas (P < 0.01). CONCLUSION: The results suggested that the expression of CD151 was closely correlated with malignant degree of pituitary adenomas, which indicated the expression of CD151 was intimately correlated with occurrence and development of pituitary adenomas. Detecting CD151 might be a vital index to predict prognosis of pituitary adenomas.

Urban garbage disposal and management in China.

This paper, probing into the present situation of urban domestic garbage by analyzing its growing trend, compositional change and regional difference, reveals the problems existing in its disposal and management in China. Meanwhile, a questionnaire was conducted in five big cities around China for surveying urban residents' attitudes towards garbage disposal and management policies and measures. Results showed the output of urban domestic garbage in Chinese cities is ever increasing, and the recoverable materials and energy in garbage composition are also increasing. The population growth, economic development, and increase of residents' expenditure level are the main factors influencing the growing output and changing composition of the garbage. Information acquired from the questionnaire showed that majority of the urban residents are in favor of the garbage reduction policies and managerial measures and are willing to collaborate with municipal government in battling against garbage. Based on the analysis and questionnaire, some policymaking-oriented suggestions such as operating the garbage disposal from a social welfare service to a sector of profit-gaining enterprises, transferring the garbage management from passive end control to active source control, promoting the classified garbage collection in cities around China, and charging garbage fees for its cleanup and disposal, have also been put forward in the paper.

The MDM2 SNP309T>G polymorphism increases bladder cancer risk among Caucasians: a meta-analysis.

Published studies have evaluated associations between the MDM2 SNP309T>G polymorphism and bladder cancer susceptibility. However, these generated inconsistent results. The aim of the present investigation was to quantify the strength of association between MDM2 SNP309T>G polymorphism and bladder cancer risk by conducting a meta-analysis. We searched PubMed and Embase for related studies that had been published in English before April 1, 2014 and associations were assessed by summarizing the odds ratios (ORs) with the corresponding 95% confidence intervals (CIs). Five case-control studies with a total of 972 cases and 1,012 controls were finally identified to be eligible for the meta-analysis. Overall, the results indicated that there was no significant association between the MDM2 SNP309T>G polymorphism and bladder cancer risk (for the allele model G vs. T: OR=1.08, 95% CI 0.85-1.36, p=0.54; for the co-dominant model GG vs. TT: OR=1.20, 95% CI 0.74-1.93, p=0.46; for the dominant model GG+GT vs. TT: OR=0.98, 95% CI 0.80-1.20, p=0.83; for the recessive model GG vs. GT+TT: OR=1.20, 95% CI 0.83-1.74, p=0.33). However, on subgroup analysis by ethnicity, significant associations were found in Caucasians in three models (for the allele model G vs. T: OR=1.41, 95% CI 1.10-1.81, p=0.006; for the co-dominant model GG vs. TT: OR=2.16, 95% CI 1.28-3.63, p=0.004; for the recessive model GG vs. GT+TT: OR=2.06, 95% CI 1.31-3.22, p=0.002). In summary, the present meta-analysis provides evidence that the genotype for the MDM2 SNP309T>G polymorphism may be associated with genetic susceptibility to bladder cancer among Caucasians.

Bone marrow-derived mesenchymal stem cells prevent the apoptosis of neuron-like PC12 cells via erythropoietin expression.

It is known that bone marrow-derived mesenchymal stem cells (BM-MSCs) are able to improve neuronal function through secretion of trophic factors in animal models of middle cerebral artery occlusion (MCAo). In this study, we demonstrated that incubation of BM-MSCs protects PC12 cells against apoptosis induced by CoCl(2) via the production of erythropoietin (EPO). Addition of CoCl(2) to BM-MSCs cultures induced the expression of EPO in a time-dependent manner. Additionally, BM-MSCs co-culture protected PC12 cells against apoptosis induced by CoCl(2) in a ratio-dependent manner. To explore whether expression of EPO induced by CoCl(2) is required for BM-MSCs-mediated cytoprotection, we transfected BM-MSCs with EPO small interfering RNA (siRNA). Knocking-down EPO abrogated increases in EPO expression induced by CoCl(2), and the cytoprotective effect of BM-MSCs. Reverse transcriptase polymerase chain reaction results showed that EPO siRNA reversed upregulation of Bcl-2, Bcl-X(L) expression and downregulation of Bax, Bak, caspase-9, and caspase-3 expression. Our results revealed that the protective effect of BM-MSCs against PC12 cell apoptosis induced by CoCl(2) might be dependent on EPO expression, at least in part, via the regulation of Bcl-2 family members and caspases.

The effect of hypoxia-inducible factor 1-alpha on hypoxia-induced apoptosis in primary neonatal rat ventricular myocytes.

AIM: To study the role of hypoxia-inducible factor 1-alpha (HIF-1alpha) on hypoxia-induced apoptosis in primary neonatal rat ventricular myocytes. METHODS: Primary neonatal rat ventricular myocytes were exposed to hypoxia for 24 hours. HIF-1alpha activity was suppressed by treating the cells with 3-(5'-hydroxymethyl-2'- furyl)-1-benzyl indazole (YC-1). The degree of cell apoptosis was assessed by Hoechst 33258 DNA staining. The levels of HIF-1alpha and the pro-apoptotic proteins Bnip3, Bax and Bad were measured with western blotting. RESULTS: On exposure to hypoxia, there was an increase in the expression levels of HIF-1alpha, and the pro-apoptotic protein Bnip3 was upregulated. Suppression of HIF-1alpha activity by YC-1 treatment was followed by blockade of hypoxia-induced apoptosis and Bnip3 expression; however, the changes in the levels of Bax and Bad expression were unclear. CONCLUSION: Acute hypoxia enhanced primary neonatal rat ventricular myocyte apoptosis through the activation of HIF-1alpha and a mechanism that perhaps involved Bnip3. Targeting HIF-1alpha may be a new strategy for reducing the degree of hypoxia-induced apoptosis in ventricular myocytes.

Intravenously administered BMSCs reduce neuronal apoptosis and promote neuronal proliferation through the release of VEGF after stroke in rats.

BACKGROUND: Transplantation of bone marrow-derived mesenchymal stem cells (BMSCs) could ameliorate neurological deficits after stroke in the rodent. OBJECTIVE: The purpose of this study was to investigate the potential mechanisms underlying the neuroprotective effects of implanted BMSCs. METHODS: Ischemic stroke was induced by permanent middle cerebral artery occlusion (MCAo) in Sprague-Dawley rats. BMSCs were intravenously transplanted at 24 hours after MCAo. Neurological function was evaluated using modified neurological severity score and Morris water maze test. Immunohistochemistry and terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling staining were performed to detect neuronal apoptosis and proliferation. The protein and mRNA levels of vascular endothelial growth factor (VEGF) were determined by ELISA and reverse transcriptase polymerase chain reaction, respectively. RESULTS: Significant improvement of neurological deficits was found in BMSC-treated rats compared with control animals at 14 and 28 days after MCAo (p<0.05). Histological evaluation showed that BMSCs treatment significantly promoted neuronal survival and proliferation in the ischemic boundary area. The expression of VEGF was predominantly increased in the ischemic hemisphere of BMSC-treated rats compared with the other groups. On the other hand, transduction of VEGF RNAi lentivirus partially attenuated the above described beneficial effects of systemically administered BMSCs. CONCLUSION: Our data suggest that intravenously administrated BMSCs facilitate neurological function, reduce neuronal apoptosis and promote neuronal proliferation through the release of VEGF.