Mitochondrial ATP 6 and 8 polymorphisms in irritable bowel syndrome with diarrhea

AIM: To investigate mitochondrial ATP 6 and 8 poly-morphisms in the colon and ileum of patients with ir-ritable bowel syndrome with diarrhea (IBS-D). METHODS: Twenty-eight patients fulfilling the Rome Ⅲ criteria for IBS-D and 28 healthy subjects were in-vestigated. All study participants underwent screening colonoscopy and mucosal biopsies were obtained from the colon and/or terminal ileum. Genomic DNA was ex-tracted from specimens based on standard protocols. Mitochondrial ATP (MT-ATP) 6 and 8 genes in speci-mens were polymerase chain reaction amplified and sequenced. Sequencing data were analyzed via Variant Reporter Software and compared with the reference sequence from Genbank (accession No. NC_012920) to indicate possible polymorphisms. The protocol was registered at www.clinicaltrials.gov as NCT01028898. RESULTS: Twenty-five polymorphic sites of MT-ATP 6 and 8 genes were detected and 12 of them were missense mutations. A median of two polymorphic sites in MT-ATP genes was found in colon specimens of controls while a median of three polymorphic sites was noted in patients with IBS-D (Mann-Whitney test, P=0.012). The variants of the colon and ileum speci-mens from the same subjects were identical in all but one case. Symptom duration in IBS was not found to be a significant factor associated with the mtDNA polymorphism (Spearman correlation, P=0.592). The mitochondrial DNA change at 8860 was present in all cases of both groups. The frequency of the 8701 poly-morphism was found to be the second most frequent; however, no statistical difference was noted between the groups (χ2 test, P=0.584). CONCLUSION: Patients with IBS-D have a higher inci-dence of MT-ATP 6 and 8 polymorphisms than healthy subjects, implying that the mtDNA polymorphism may play a role in IBS-D.

Epstein-Barr Virus EA-IgA, VCA-IgA, and EBVNA-IgG Antibodies in a Population of Wuhan, China

The study investigated the distribution of Epstein-Barr virus(EBV)EA-IgA,VCAIgA,and EBVNA-IgG antibodies in a local population of Wuhan,China.Chemiluminescence immunoassay(CL1A)was used to detect EBV EA-IgA,VCA-IgA,and EBVNA-IgG antibodies in 972 subjects undergoing physical examination in Wuhan,and the results were analyzed.The detection rate of EBV was positively correlated with age.In the 972 cases,there was significant difference between different genders in the positive rate of VCA-IgA and EBVNA-IgG.Moreover,the positive rate of VCA-IgA and EBVNA-IgG was higher in men>60 years old than in those<60 but no significant differences were found in three antibodies among various age groups.Our results suggested that the EBV infection should be intensively monitored in elderly people in Wuhan.

Morphology Evolution,Conductive and Viscoelastic Behaviors of Chemically Reduced Graphene Oxide Filled Poly(methyl methacrylate)/Poly(styrene-co-acrylonitrile) Nanocomposites during Annealing

The effect of chemically reduced graphene oxide （CRGO） on the phase separation behavior of poly（methyl methacrylate）/poly（styrene-co-acrylonitrile） （PMMA/SAN） blends and the simultaneous response of rheological and conductive behavior of PMMA/SAN/CRGO nanocomposites upon annealing above the phase-separation temperatures were investigated. The introduction of CRGO causes the decrease of binodal temperature and the increase of spinodal temperature for PMMA/SAN blends and then enlarges their metastable regime. During annealing, the well-dispersed CRGO in the homogeneous blend matrix tends to be selectively located in the SAN-rich phase with the evolution of phase separation and then the CRGO further agglomerates effectively in the SAN-rich phase to form the conductive pathway. Thermal-induced dynamic percolation is observed for both the resistivity p and dynamic storage modulus G＇ as a function of annealing time. The resistivity variation is ascribed to the agglomeration of CRGO in the SAN-rich phase, while the modulus evolution is attributed to the combined contribution of phase separation for blend matrix and the agglomeration of CRGO in the SAN-rich phase.

Enhanced αγ′ Transition of Poly(vinylidene fluoride) by Step Crystallization and Subsequent Annealing

Poly（vinylidene fluoride）（PVDF） exhibits pronounced polymorphs. Its γ phase is attractive due to the electroactive properties. The γ-PVDF is however difficult to obtain under normal crystallization condition. In a previous work, we reported a simple melt-recrystallization approach for producing γ-phase rich PVDF thin films through selective melting and subsequent recrystallization. We reported here another approach for promoting the αγ′ phase transition to prepare γ-phase rich PVDF thin films. To this end, a stepwise crystallization and subsequent annealing process was used. The idea is based on a quick generation of a large amount of α-PVDF crystals with some of their γ-PVDF counterparts at suitable crystallization temperature and then annealing at a temperature above the crystallization temperature for enhancing the molecular chain mobility to overcome the energy barrier of phase transition. It was found that crystallizing the PVDF melt first at 152 °C for 4 h, then quenching to room temperature and finally annealing the sample at 160 °C for 100 h was the most efficient to produce γ-PVDF rich films. This is related to the melting and recrystallization of the α-PVDF crystals produced during quenching in the annealing process at 160 °C, which favors the formation of γ-PVDF crystals for triggering the αγ′ phase transition.

Structure and Properties of β-Polypropylene Reinforced by Polypropylene Fiber and Polyamide Fiber

Matrix/fiber composites of,β-form isotactic polypropylene （iPP） matrix and α-iPP or PA6 fibers were prepared by laminating technique under different preparation temperatures. The mechanical properties and interracial morphologies of these composites were studied by tensile test, optical microscopy and scanning electron microscopy, respectively. The experimental results show that the tensile yield load and tensile modulus of β-iPP/PA6 matrix/fiber systems increased significantly at the expense of elongation at break. These mechanical properties show essentially no dependence on the sample preparation temperature. On the other hand, the mechanical properties of iPP matrix/fiber single polymer composites depend strongly on the sample preparation temperature. At low sample preparation temperature, e.g., 172 ℃, the solid cr-iPP fiber induces tr-iPP crystallization, leading to the formation of a-iPP transcrystalline layer around the fiber. This results in a remarkable increment of the tensile yield load and tensile modulus. The elongation at break is also much better than that of the iPP/PA6 matrix/fiber system. It reflects a better interracial adhesion of the single polymer composite compared with the iPP/PA6 composite. At higher sample preparation temperature, e.g., 174 ℃ or 176 ℃, the partial surface melting of the oriented fiber allows interdiffusion of iPP molecular chains in the molten fiber and matrix melt. The penetration of matrix chains into the molten iPP fiber results in some iPP molecular chains being included partially in the recrystallized fiber and the induced β-transcrystalline layers. This kind of configuration leads to an improvement of interfacial adhesion between the fiber and matrix, which causes a simultaneous increase of the tensile yield load, tensile modulus and elongation at break of β-iPP.

Structure of Friction-transferred Highly Oriented Poly(3-hexylthiophene) Thin Films

Oriented thin films of P3HT were obtained by a friction-transfer technique. The morphology and structure of the film were studied by means of optical microscopy, atomic force microscopy and transmission electron microscopy. Optical microscopy observation indicates that large size well-ordered P3HT thin films can be produced by a friction-transfer technique. Highly ordered lamellae were observed in P3HT friction-transferred films by electron microscopy. Electron diffraction results confirm the existence of high orientation with the a- and c-axes of P3HT crystals aligned in the film plane while the c-axis parallel to the friction-transfer direction. The atomic force microscopy observation of the as-prepared P3HT thin film shows, however, a featureless top surface morphology, indicating the structure inhomogeneity of the obtained film. To get highly oriented P3HT thin films with homogenous structure, high temperature annealing, solvent vapor annealing and self-seeding recrystallization of the friction-transferred film were performed. It is confirmed that solvent vapor annealing and self-seeding recrystallization methods are efficient in improving the surface morphology and structure of the friction- transferred P3HT thin film. Highly oriented P3HT films with unique structure can be obtained through friction-transfer with subsequent solvent vapor annealing and self-seeding recrystallization.

A reviving templating method for multiple nanostructures

Binary materials,comprised by two dissimilar components in one matrix,already exist in nature from the subatomic to the universal scale with different kinds of forms(e.g.,nuclei and electrons,matter and antimatter)[1].With the progress of nanotechnology,binarymaterials assembled in nanoscale become an important