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Irritable bowel syndrome (IBS) is a gastrointestinal disorder with no structural damage and biochemical abnormality, and its pathogenic mechanism is still unclear. Variety of drugs, psychotherapy, diet regulation and other methods have been used by modern medicine to relieve symptoms, but the effect is not satisfactory. In recent years, TCM treatment of IBS has attracted widespread attention, especially for constipation type and diarrhea type. Among the many experiments, most of the traditional Chinese medicine experiments aimed at the 5-HT signaling pathway have achieved good results. Therefore, this paper summarizes the main mechanisms and results of traditional Chinese medicine based on 5-HT in the treatment of IBS, in order to provide a reference for subsequent research.

The morphology distribution of a model polymer blend, polystyrene (PS)/polyethylene (PE), molded by multi-melt multi-injection molding (MMMIM) process was studied by scanning electronic microscopy and polarizing light microscopy. An unusual double skin/core morphology was observed. The minor phase, PS, showed highly deformed morphology in both the skin layer near the mold wall and the core layer near the skin/core layer's interface. Meanwhile, in the regions that highly deformed PS phase showed, highly ordered cylindritic crystal structures of PE are also formed. As we all know the driving force and the basic prerequisite to deform the dispersed droplet and form the oriented crystal structure is the shear field. So an attempt was made to correlate the dispersed phase morphology, crystalline morphologies, and shear rate. The shear rate, estimated via the capillary number, across the thickness of the parts molded by MMMIM was bimodal. Even if the coalescence and relaxation of the dispersed phase during and after mold filling cannot be ignored, both the highly dispersed PS domains and the highly ordered crystal structure of PE showed in the regions with the maximum calculated shear rate, which is consistent with the generally accepted theories that strong shear flow is favorable to the formation of the oriented structures., INTRODUCTION Multimelt multi-injection molding (MMMIM) [1], an innovative molding process, has been developed from conventional injection molding (CIM), and its main feature is that the mold cavity is partially filled [...]

Aim: A comprehensive understanding of nanoparticle (NP)-protein interaction (protein corona formation) is required. So far, many factors influencing this interaction have been investigated, like size and ζ potential. However, NPs exposure concentration has always been ignored. Herein, we aim to disclose the correlation of NPs exposure concentration with protein adsorption. Materials & methods: Four polymeric NPs systems possessing similar sizes (230 ± 20 nm) but varied ζ potentials (−30 ∼ +40 mv) were prepared. Physicochemical properties and protein adsorption upon NP-protein interaction were characterized. Results: Protein adsorption capacity and adsorbed protein types were NPs concentration-dependent. Conclusion: Considering the critical impacts of protein adsorption on NPs delivery, our work could be an urgent warning about the possible risks of dosage adjustment of nanoformulations. [ABSTRACT FROM AUTHOR]

A series of microporous polyimide networks with porphyrin units (Pr-MPIs) were facilely synthesized through a one-step solution polymerization process. Of particular interest is that Pr-MPI-1 containing distorted spirobisindane unit revealed the highest BET surface area (953 m/g), total pore volume (0.75 cm/g), and extreme hysteresis between the N adsorption and desorption isotherm. Further study revealed the prepared Pr-MPI-1 exhibited a synergistic structural effect on exceptional uptake of volatile organic compounds (VOCs) due to the high porosity and highly distorted spirobisindane structure enabled large interface and the swellability. This new approach would open up a facile approach toward the preparation of highly swellable high performance polymeric microporous materials, which are deeply wanted for environment-related applications such as VOCs adsorption and oil/water separation. [ABSTRACT FROM AUTHOR]

Dicumyl peroxide (DCP) was introduced into thermoplastic polyurethane (TPU) toughened poly(L-lactide) (PLLA) blends. The results showed that the presence of DCP at relatively high concentration (0.2–0.5 wt.%) not only resulted in the homogeneous distribution of TPU particles with largely decreased particle size but also improved the interfacial interaction between PLLA and TPU components. Consequently, super toughened PLLA/TPU blends with largely enhanced impact strength were achieved successfully. The toughening mechanism was analyzed based on the impact-fractured surface morphologies of samples. Further enhanced impact toughness could be achieved by introducing crystalline structure to PLLA matrix, which was realized by annealing treatment. [ABSTRACT FROM AUTHOR]

The effect of viscosity ratio (ηcore/ηskin) on the crystalline morphologies of the bars molded by multi-melt multi-injection molding (MMMIM) was investigated by fixing a kind of high density polyethylene (HDPE) with a high molecular weight as the skin material and tuning the viscosity ratio by the viscosities of different core melts. The hierarchical morphologies and mechanical properties were investigated by PLM, SEM, 2D-WAXS and tensile testing. It was found that higher viscosity ratio facilitated the interaction between the skin and core melts ascribed to greater chain entanglement, and induced a higher degree of molecular orientation accompanied by improved mechanical properties. [ABSTRACT FROM PUBLISHER]

A green approach to the synthesis and morphological control of high performance polyimides and their nanohybrid shish-kebabs in glycerol through reaction-induced crystallization of nylon-salt-type monomers was reported. Crystalline polyimide nanoplates can be observed by direct polycondensation of pyromellitic acid with various kinds of aliphatic or aromatic diamines. With the existence of carbon nanotubes, the polyimides can be successfully decorated on the surface of CNTs through a reaction-induced hetero-epitaxial crystallization process, and resulted in novel polyimide/CNT nanohybrid shish-kebabs (NHSKs) structures. The morphologies of the NHSKs can be fine-tuned through changing the concentration of monomers or the reaction temperature, especially through the introduction of dynamic imine chemistry, the formation process of NHSKs can be attributed to a soft epitaxy mechanism. Thus a green approach for the synthesis of high performance polyimides and their CNT based nanohybrid structures was explored, which should be of great value for their applications in high performance reinforced nanocomposites. [ABSTRACT FROM AUTHOR]

Maleic anhydride grafted styrene-ethylene/butadiene-styrene block copolymer (SEBS-g-MA) was introduced into poly(trimethylene terephthalate) (PTT) to prepare the PTT/SEBS-g-MA blends. The results showed that SEBS-g-MA exhibited dispersed particles and the particle sizes changed with the variation of its content. Furthermore, the crystallization behavior of PTT matrix was restricted by adding SEBS-g-MA. Mechanical properties measurements proved that PTT could be toughened by SEBS-g-MA and the toughening effect was greatly dependent upon the SEBS-g-MA content and the measurement conditions. The toughening mechanism was mainly attributed to the largely enhanced resistance of the crack propagation during the fracture process. [ABSTRACT FROM PUBLISHER]

ABSTRACT Graphene oxide (GO) and carbon nanotubes (CNTs) and their compound were introduced into semicrystalline poly( l-lactide) (PLLA) to prepare the corresponding binary and/or ternary nanocomposites, respectively. The dispersion states of nanofillers in different nanocomposites were investigated using UV-Vis spectroscopy, scanning electron microscopy (SEM) and rheological measurement. The results showed that when GO and CNTs were simultaneously present in the PLLA matrix, good dispersion states of both GO and CNTs could be achieved and the ternary nanocomposites exhibited percolated network structure. The effects of different nanofillers on the crystallization behavior of PLLA matrix were comparatively investigated under the different crystallization conditions including melt crystallization process (nonisothermal and isothermal crystallization from the melt) and cold crystallization (crystallization occurring from an amorphous state during the annealing process). The results showed that GO and CNTs exhibited apparent synergistic effects in improving crystallization ability and enhancing crystallinity of PLLA matrix. Study on the thermal stability of nanocomposites showed that the presence of nanofillers greatly improved the thermal stability of PLLA matrix. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40143. [ABSTRACT FROM AUTHOR]

To investigate the correlation in growth between A. actinomycetemcomitans and cariogenic bacteria of S. mutans, L. acidophilus, A. naeslundii, A. viscosus in vitro. METHODS: Using improvement agar diffusion method and dual-species (A. actinomycetemcomitans with each of cariogenic bacteria) incubation in BHI broth, we studied the relationship between A. actinomycetemcomitans and 4 kinds cariogenic bacteria in growth. The characteristics and percentage of A. actinomycetemcomitans in dual-species biofilms were detected with SEM and CFU (colony forming units). The data were analyzed for significance using an independent two-sample t test with SPSS 10.0 software package. RESULTS: The agar diffusion essay showed that A. actinomycetemcomitans had no effect on the growth of S. mutans, L. acidophilus, A. naeslundii and A. viscosus. While these 4 kinds of cariogenic bacteria could inhibit the growth of A. actinomycetemcomitans. The ratio of A. actinomycetemcomitans in the dual-species suspension decreased gradually. In dual-species BHI broth, the proportion of A. actinomycetemcomitans cultured alone ahead of 12 hours decreased as well, which came to 0 at 24-hour in S. mutans and L. acidophilus groups. There was significant difference between different time groups (P<0.05). The single A. actinomycetemcomitans was failed to form three-dimensional biofilm and just a small quantity of cells accumulated and adhered. on the contrary, the 4 kinds of single cariogenic bacteria could form mature biofilms respectively by themselves at 48-hour, of which the appearance of biofilms had no apparent change to that of single cariogenic bacteria after mixing A. actinomycetemcomitans. CFU of dual-species biofilms indicated that the percentage of A. actinomycetemcomitans in biofilms decreased gradually by changing medium per 12 hours. These were significant difference among the three time spots (P<0.05). CONCLUSION: The study shows that S. mutans, L. acidophilus, A. naeslundii and A. viscosus could inhibit the growth of A. actinomycetemcomitans in vitro. [ABSTRACT FROM AUTHOR]

• GO possesses intrinsic antibacterial activity to various bacterial pathogens. • A parabolic relation exists between the size and antibacterial activity of GO. • Increasing GO size enhances cell entrapment effect but reduces cutting effect. • Decreasing GO size reduces cell entrapment effect but enhances cutting effect. The antibiotics-independent antimicrobial activity of graphene oxide (GO) is of great importance since antibiotic therapy is facing great challenges from drug resistance. However, the relations of GO size with its antimicrobial activity and how the size regulates the antibacterial mechanisms are still unknown. Herein, we fabricated four GO suspensions with different sizes and demonstrated the parabolic relationship between GO size and its antibacterial activity against the Gram-positive cariogenic bacterium Streptococcus mutans. More interestingly, we found out how GO size regulated the nano-bio interaction-based physical antibacterial mechanisms. Increasing the size reduced the cutting effect but enhanced the cell entrapment effect, and vice versa. In conclusion, GO size affects its edge density and lateral dimension, further regulates its physical antibacterial mechanisms in different orientations and ultimately determines its activity. These findings provide a deep understanding of GO antibacterial property and may guide the design and development of GO for clinical use. [ABSTRACT FROM AUTHOR]