Polymer monolith-integrated multilayer poly(dimethylsiloxane) microchip for online microextraction and capillary electrophoresis.

We reported the in situ synthesis and use of porous polymer monolith (PPM) columns in an integrated multilayer PDMS/glass microchip for microvalve-assisted on-line microextraction and microchip electrophoresis for the first time. Under the control of PDMS microvalves, the grafting of the microchannel surface and in situ photopolymerization of poly(methacrylic acid-co-ethylene glycol dimethacrylate) monolith in a defined zone were successfully achieved. Different factors including the surface grafting, polymerization time, PDMS elastic properties (ratio of oligomer/curing reagent) and UV intensity that affect the monolith synthesis in the PDMS microchannel were investigated and optimized. Dopamine, a model analyte, has been online microextracted, eluted, electrophoresized and electrochemically detected in the microchip, with a mean concentration enrichment factor of 80 (n=3). The results demonstrated that the PPM could be synthesized successfully in the PDMS microchip with a homogeneous structure and excellent mechanical properties. Furthermore, owing to the intrinsic character using PDMS in large-scale integrated microsystems, the implantation of PPM pretreatment units in PDMS microchips would make it possible to deal with complicated analytical processes in a high-throughput way.

BRD4 blockage alleviates pathological cardiac hypertrophy through the suppression of fibrosis and inflammation via reducing ROS generation.

Hypertension is an essential regulator of cardiac injury and remodeling. However, the pathogenesis that contributes to cardiac hypertrophy remains to be fully explored. BRD4, as a bromodomain and extra-terminal (BET) family member, plays an important role in critical biological processes. In the study, our results showed that BRD4 expression was up-regulated in human and mouse hypertrophied hearts, and importantly these effects were modulated by reactive oxygen species (ROS) generation. In angiotensin II (Ang II)-treated cardiomyocytes, BRD4 decrease markedly blunted the prohypertrophic effect, which was further promoted by the combinational treatment of ROS scavenger (N-acetyl-cysteine, NAC). In addition, NAC pre-treatment markedly elevated the anti-fibrotic role of BRD4 suppression in Ang II-incubated cardiomyocytes by repressing transforming growth factor ß1 (TGF-ß1)/SMADs signaling pathway. NAC combined with BRD4 reduction further alleviated inflammation and oxidative stress in Ang II-exposed cardiomyocytes, which was partly through inhibiting nuclear factor-κB (NF-κB) signaling and improving nuclear erythroid factor 2-related factor 2 (Nrf-2)/heme oxygenase-1 (HO-1) pathway, respectively. Furthermore, the in vivo results confirmed the protective effects of BRD4 suppression on mice against aortic banding (AB)-induced cardiac hypertrophy, as evidenced by the reduced cross sectional area and fibrotic area using H&E and Masson trichrome staining. What's more, the degree of cardiac hypertrophy (ANP and BNP), the expression of pro-fibrotic genes (TGF-ß1, Collagen I, Collagen III and CTGF), the levels of inflammation and oxidative stress were all significantly attenuated by the blockage of BRD4 in AB-operated mice. Taken together, repressing BRD4 expression was found to confer a protective effect against experimental cardiac hypertrophy in mice, demonstrating its potential as an effective therapeutic target for pathological cardiac hypertrophy.

Association of Optic Radiation Integrity with Cortical Thickness in Children with Anisometropic Amblyopia.

Previous studies have indicated regional abnormalities of both gray and white matter in amblyopia. However, alterations of cortical thickness associated with changes in white matter integrity have rarely been reported. In this study, structural magnetic resonance imaging and diffusion tensor imaging (DTI) data were obtained from 15 children with anisometropic amblyopia and 15 age- and gender-matched children with normal sight. Combining DTI and surface-based morphometry, we examined a potential linkage between disrupted white matter integrity and altered cortical thickness. The fractional anisotropy (FA) values in the optic radiations (ORs) of children with anisometropic amblyopia were lower than in controls (P < 0.05). The cortical thickness in amblyopic children was lower than controls in the following subregions: lingual cortex, lateral occipitotemporal gyrus, cuneus, occipital lobe, inferior parietal lobe, and temporal lobe (P < 0.05, corrected), but was higher in the calcarine gyrus (P < 0.05, corrected). Node-by-node correlation analysis of changes in cortical thickness revealed a significant association between a lower FA value in the OR and diminished cortical thickness in the following subregions: medial lingual cortex, lateral occipitotemporal gyrus, lateral, superior, and medial occipital cortex, and lunate cortex. We also found a relationship between changes of cortical thickness and white matter OR integrity in amblyopia. These findings indicate that developmental changes occur simultaneously in the OR and visual cortex in amblyopia, and provide key information on complex damage of brain networks in anisometropic amblyopia. Our results also support the hypothesis that the pathogenesis of anisometropic amblyopia is neurodevelopmental.

[Research Progress on role of Abnormal Tryptophan Metabolism in Immune Thrombocytopenia].

Immune thrombocytopenia (ITP) is a common acquired autoimmune hematological disorders. Platelet autoantibodies lead to the decrease of platelet production and (or) increase of its destruction. The latest researches showed that the abnormal tryptophan metabolism mediated by indoleamine-2, 3-dioxygenase(IDO) is related with the pathogenesis of ITP. The patients with ITP show less expression of IDO, reduction of Treg cells and increase of autoreactive T cells and autoantibodies. CTLA-4-Ig can improve the expression of IDO in the patients with ITP, which also can inhibit the proliferation and activation of self-reactive T cells. Thus, clarifying the abnormal tryptophan metabolism mediated by IDO may provide a new idea for improving the understand of the pathogenesis and treatment of ITP. This review focuses on reasearch progress of the tryptophan metabolism mediated by IDO and ITP.

Can Carrier-Mediated Delivery System Promote the Development of Antisense Imaging?

PURPOSE: We aimed to explore the feasibility of transfection methods for antisense imaging. PROCEDURES: Antisense oligonucleotides (ASON) targeted to the mRNA of hTERT gene were synthesized and labeled with Technetium-99m and fluorescein isothiocyanate (FITC), respectively. Then, ASON was combined with transfection reagent Lipofectamine 2000 and Xfect(TM), named Lipo-ASON and Xfect-ASON, respectively. After transfection, the labeled ASON was characterized in hNPCs-G3 and hRPE cells. Reverse transcription polymerase chain reaction (RT-PCR) and Western blotting were performed to assay the hTERT mRNA and protein levels after hNPCs-G3 cells were incubated with Lipo-ASON, Xfect-ASON, and naked ASON. In addition, Lipo-ASON, Xfect-ASON, and naked ASON were injected into tumor-bearing mice, and the biodistribution in vivo was performed. RESULTS: The presence of two transfection reagents significantly increased intracellular uptake of radiolabeled ASON in both cell lines compared with naked ASON (p < 0.05). However, there was no significant difference in cellular uptake rates of Lipo-ASON and Xfect-ASON between hNPCs-G3 and hRPE cells. In comparison with naked ASON, the fluorescence intensity was strongly enhanced after binding to transfection reagents. Furthermore, the levels of hTERT mRNA and protein were significantly reduced in cells treated with Lipo-ASON and Xfect-ASON (p < 0.05), but naked ASON had no significant effect on hTERT expression level. The biodistribution study indicated that tumor radioactivity uptake of radiolabeled ASON for naked ASON, Lipo-ASON, and Xfect-ASON group was low and shown no significant difference in vivo. CONCLUSIONS: Lipofectamine transfection and Xfect(TM) transfection were not effective delivery methods of ASON for antisense imaging.

[Relationship between polymorphisms of tumor necrosis factor alpha gene and primary myelodysplastic syndromes].

OBJECTIVE: To investigate the association of single nucleus polymorphisms(SNP)of tumor necrosis factor alpha (TNF-α) gene (-308 G>A and -238 G>A genotypes) with susceptibility to primary myelodysplastic syndromes (MDS). METHODS: Two SNPs (TNF-α-308 G>A,TNF-α-238 G>A) of TNF-α gene were detected by Taqman probes in 341 MDS patients and 365 unrelated-healthy controls. RESULTS: Compared to healthy controls, the frequency of TNF-α-308 AA+AG genotype and A allele increased (18% vs 10%, P=0.015, 9% vs 5%, P=0.021, respectively) in refractory cytopenia with multilineage dysplasia (RCMD) patients. There was no correlation of TNF-α-308 G>A genotype and allele frequency between MDS and controls. No difference in the genotype and allele frequency of TNF-α-238 G>A were found between controls and MDS or the subtypes of MDS (P>0.05). We did not find any linkage between plasma level of TNF-α and TNF-α-308 G>A or TNF-α-238 G>A genotype. Statistic differences were observed between platelet count[58(1-611)×109/L vs 90(7-352)×109/L]and bone marrow blasts in MDS patients carrying TNF-α-308 G>A GG and AA+AG genotype (P=0.024, 0.019, respectively). CONCLUSION: TNF-α-308 G>A polymorphism was correlated with susceptibility to MDS-RCMD.

Analysis on 71 patients with polycythemia vera.

The aim of this study was to analyse the clinical characteristics and laboratory data, treatment and prognosis of polycythemia vera (PV). A retrospective study was performed for 71 PV patients treated in our hospital during January 2001 to July 2011 including analysis of clinical characteristics, laboratory data, myelogram chromosome karyotypes, BCR/ABL and JAK2V617F genes, as well as lactate dehydrogenase (LDH) and neuron-specific enolase (NSE) levels in serum and so on. The results showed that 71 patients (37 males and 34 females with a average age of 57.8 years) were diagnosed. Thrombosis and embolism occurred in 34 patients (47.89%), hemorrhage in 10 patients (14.08%), splenomegaly occurred in 44 patients. The onset of the disease was insidious, 13 patients (18.31%) were found to have PV during the treatments for other diseases. The average hemoglobin at diagnosis was 206.31 (171 - 242) g/L. JAK2V617F mutation was detected in 31 (81.58%) of 38 patients studied. The average levels of serum LDH and NSE were higher than normal and both positively correlated with hemoglobin (P = 0.007, P = 0.005). The disease outcomes were myelofibrosis for 3 patients, death from cerebral hemorrhage for 1 patient, and death from ineffective chemotherapy in 1 patient with ANLL-M2. It is concluded that PV is a chronic myeloproliferative disorder characterized predominantly by thrombosis and hemorrhage. The serum LDH and NSE levels are higher than the normal values. It is inferred that the serum LDH and NSE levels can reflect the degree of malignant proliferation of bone marrow hematopoietic cells and also can be used as an indicator to judge the therapeutic effect of PV.

[JAK2 exon 12 mutations in patients with Philadelphia (Ph) chromosome-negative myeloproliferative neoplasms].

OBJECTIVE: To investigate JAK2 exon 12 mutations in patients with Philadelphia (Ph) chromosome-negative myeloproliferative neoplasms (MPN) and the clinical characteristics of patients with JAK2 exon 12 mutants. METHODS: Allele-specific PCR (AS-PCR) was applied to identify JAK2 V617F mutation. Genomic DNA corresponding to exon 12 of JAK2 gene and epigenetic regulator gene (TET2, ASXL1, EZH2) were amplified by polymerase chain reaction (PCR). Identification of mutants was by direct sequencing and classification of mutation types by sequencing followed by plasmid cloning. SNP genotyping of two 46/1 tag SNPs, rs12340895 and rs10974944, was analyzed using commercially available Taqman assays on the 7500HT real-time PCR instrument according to standard protocols. RESULTS: No JAK2 exon 12 mutation was detected in patients with ET, PMF or JAK2 V617F positive PV. Among 13 JAK2 V617F negative PV patients, JAK2 exon 12 mutation was detected as N542-E543del in 2(15.4%) patients who presented with a phenotype of predominant erythrocytosis and erythroid colonic grown from their bone marrow samples in the absence of exogenous EPO, reduced serum erythropoietin (EPO) level, and no mutations in TET2, ASXL1 or EZH2 genes. One of the affected patients was heterozygous for 46/1 but the second was negative for this haplotype. CONCLUSION: There was no need to detect JAK2 exon 12 mutation in ET, PMF or MPN-U patients without JAK2 V67F mutation. Ph negative MPN patients with JAK2 exon 12 mutations had somewhat unique clinical and laboratory features.

[Diagnosis of aortic intramural hematoma by electron beam CT].

OBJECTIVE: To assess the value of electron beam CT (EBCT) in the diagnosis of aortic intramural hematoma (AIH). METHODS: Twenty-five patients who complained of acute chest and back pain were scanned with an EBCT scanner (Imatron C-150) using contrast-enhanced continuous volume scanning (CVS) for establish the diagnosis of AIH. RESULTS: Seven patients were diagnosed as having Stanford type A, and the others as type B AIH. The direct features of AIH in EBCT included crescent or circular thickening (>5 mm) of the aortic wall without signs of lumen formation resulting from intimal rupture. The indirect features included calcification ingression (7 cases), penetrating ulcer (12 cases), atherosclerosis (18 cases) and leakages (5 cases). The complicating features included pericardial effusion (5 cases), pleural effusion (14 cases), involvement of the large branches (5 cases), aortic dissection (3 cases) and aneurysms (4 cases). CONCLUSION: EBCT can provide important information for the diagnosis and treatment of AIH, and can be useful for follow-up observation of the patients.

Construction and activity assay of the activating transcription factor 3 reporter vector pATF/CRE-luc.

Activating transcription factor 3 (ATF3), a member of the activating transcription factor/cAMP responsive element binding protein (ATF/CREB) family of transcription factors, is induced by many physiological stresses. To investigate the activity of ATF/CREB in cells with physiological stresses, we developed a practical reporter vector, the plasmid pATF/CRE-luc, bearing activating transcription factor/cAMP responsive element (ATF/CRE) binding sites. This plasmid was constructed by inserting three repeats of the ATF/CRE binding element into the plasmid pG5luc, replacing the GAL-4 binding sites. The plasmids pACT/ATF3 and pATF/CRE-luc were transfected into HeLa and NIH3T3 cells, respectively, and the results showed that the expression of luciferase was increased in a dose-dependent manner on plasmid pACT/ATF3. The data suggested that the plasmid pATF/CRE-luc could be used as a sensitive and convenient reporter system of ATF3 activity.

[Fusion expression, purification and bioactivity detection of human defensinalpha (HDalpha)].

AIM: To obtain recombinant human defensin alpha(HDalpha) and detect its biological activity, so as to facilitate further research. METHODS: The HDalpha gene fragment with hydroxylamine cleavage site was synthesized, and then cloned into pBV220-IL-4 vector to construct pBV220-IL-4-HDalpha. The constructed vector which was confirmed to be correct by sequencing was transformed into E.coli DH5alpha and the IL-4-HDalpha fusion protein was expressed under temperature induction. After fusion protein was cleaved to remove IL-4 by hydroxylamine, purification and renaturation was performed. HDalpha's characteristics were identified by SDS-PAGE and bioactivity detection. RESULTS: After temperature induction, the expressed fusion protein which accounted for about 20% of total bacterial protein existed mainly in the form of inclusion body. After cleaving by hydroxylamine, the purity of obtained HDalpha was about 99.8%. Bacteriostatic test and clone forming test showed that recombinant HDalpha could obviously inhibit the growth of bacteria. CONCLUSION: The recombinant expression plasmid for HDalpha gene has been constructed successfully and obtained engineering bacteria can stably express target protein. Furthermore, techniques of purification and renaturation was set out, which lays the foundation for further functional study and application of HDalpha.