Roles of bacterial extracellular vesicles in systemic diseases

Accumulating evidence suggests that in various systems, not all bidirectional microbiota–host interactions involve direct cell contact. Bacterial extracellular vesicles (BEVs) may be key participants in this interkingdom crosstalk. BEVs mediate microbiota functions by delivering effector molecules that modulate host signaling pathways, thereby facilitating host–microbe interactions. BEV production during infections by both pathogens and probiotics has been observed in various host tissues. Therefore, these vesicles released by microbiota may have the ability to drive or inhibit disease pathogenesis in different systems within the host. Here, we review the current knowledge of BEVs and particularly emphasize their interactions with the host and the pathogenesis of systemic diseases

Degradable hydrogel fibers encapsulate and deliver metformin and periodontal ligament stem cells for dental and periodontal regeneration

Human periodontal ligament stem cells (hPDLSCs) are promising cells for dental and periodontal regeneration. Objective: This study aimed to develop novel alginate-fibrin fibers that encapsulates hPDLSCs and metformin, to investigate the effect of metformin on the osteogenic differentiation of hPDLSCs, and to determine the regulatory role of the Shh/Gli1 signaling pathway in the metformin-induced osteogenic differentiation of hPDLSCs for the first time. Methodology: CCK8 assay was used to evaluate hPDLSCs. Alkaline phosphatase (ALP) staining, alizarin red S staining, and the expression of osteogenic genes were evaluated. Metformin and hPDLSCs were encapsulated in alginate-fibrinogen solutions, which were injected to form alginate-fibrin fibers. The activation of Shh/Gli1 signaling pathway was examined using qRT-PCR and western blot. A mechanistic study was conducted by inhibiting the Shh/Gli1 pathway using GANT61. Results: The administration of 50 μM metformin resulted in a significant upregulation of osteogenic gene expression in hPDLSCs by 1.4-fold compared to the osteogenic induction group (P < 0.01), including ALP and runt-related transcription factor-2 (RUNX2). Furthermore, metformin increased ALP activity by 1.7-fold and bone mineral nodule formation by 2.6-fold (P<0.001). We observed that hPDLSCs proliferated with the degradation of alginate-fibrin fibers, and metformin induced their differentiation into the osteogenic lineage. Metformin also promoted the osteogenic differentiation of hPDLSCs by upregulating the Shh/Gli1 signaling pathway by 3- to 6- fold compared to the osteogenic induction group (P<0.001). The osteogenic differentiation ability of hPDLSCs were decreased 1.3- to 1.6-fold when the Shh/Gli1 pathway was inhibited, according to ALP staining and alizarin red S staining (P<0.01). Conclusions: Metformin enhanced the osteogenic differentiation of hPDLSCs via the Shh/Gli1 signaling pathway. Degradable alginate-fibrin hydrogel fibers encapsulating hPDLSCs and metformin have significant potential for use in dental and periodontal tissue engineering applications. Clinical Significance: Alginate-fibrin fibers encapsulating hPDLSCs and metformin have a great potential for use in the treatment of maxillofacial bone defects caused by trauma, tumors, and tooth extraction. Additionally, they may facilitate the regeneration of periodontal tissue in patients with periodontitis

Clinical study on the sensitivity test guided hepato-arterial/portal-vein chemotherapy in patients with unresectable hepatocellar carcinoma

Purpose: Approximately 20 % of tumors have the opportunity to be resected in patients with hepatocellar carcinoma (HCC) and their prognoses were acceptable. For the unrespectable HCC, however, the outcomes were rather poor because the specialty of the tumor blood supply and the tumor was insensitive to the chemotherapy drug. The objective of this study was to find sensitive drugs for individual patients and determine the safety and antitumor activity of hepatic intra-arterial and portal vein infusion chemotherapy. Methods: A total of 120 patients with the mean patient age of 56 years and with unresectable HCC were randomly divided into experimental group and control group. The experiment group was infused through an intra-arterial and portal vein catheter 3 different drugs were chosen by the results of drug sensitive test, whereas the control group was treated for TACE. The changes in tumor-size and AFP, two-step operation rate, survival rate, and complications were observed in these patients. Results: The tumor size reduced in 28(47.6 %) cases, stabilized in 14(23.3 %) cases, and progressed in 18(30 %) cases in experimental group as measured by CT or MRI after six chemotherapy  cycles, whereas the corresponding data was 17(28.5 %) cases, 7(11.5 %) cases and 36(60 %) cases in the control group (P < 0.05). The AFP was declined in 51 cases in experimental group and in 30 cases in control group (P < 0.05). In the experimental group, the median follow-up time was 21 months; the overall survival rates (OS) of 6 months, 12 months, and 18 months were 86 %, 72 %, and 65 %, respectively. In the control group, the median follow-up time was 16 months; the OS rates of 6 months and 12 months were 58 % and 40 %, respectively. Six patients in the experimental group and 3 patients in the control group had two-step operation. There was no severe incidence of complications in both groups. In the experimental group, 2 (3 %) patients had wound infection, 8 cases had the chemotherapy relative diarrhea, and 18 (30 %) cases had grade Ⅰ or Ⅱ  bone marrow suppression. In the control group, the chemotherapy relative diarrhea were 15 (25 %) cases and grade Ⅰ or Ⅱ bone marrow suppression were 33 (55 %) cases. Conclusion: The artery and portal vein pump transfusion chemotherapy guided by drug sensitive test was efficient for HCC treatment. The patients can get longer OS and lower complication incidence.--------------------------------------------------------Cite this article as: Wu D, Wei S, Luo C, Wu X, Feng Y, Zhang F, Nie L, Xia X. Clinical study on the sensitivity test guided hepato-arterial/portal -vein chemotherapy in patients with unresectable hepatocellar carci-noma. Int J Cancer Ther Oncol 2014; 2(2):02029. DOI: 10.14319/ijcto.0202.

Porous Adsorption Materials for Carbon Dioxide Capture in Industrial Flue Gas

Due to the intensification of the greenhouse effect and the emphasis on the utilization of CO2 resources, the enrichment and separation of CO2 have become a current research focus in the environment and energy. Compared with other technologies, pressure swing adsorption has the advantages of low cost and high efficiency and has been widely used. The design and preparation of high-efficiency adsorbents is the core of the pressure swing adsorption technology. Therefore, high-performance porous CO2 adsorption materials have attracted increasing attention. Porous adsorption materials with high specific surface area, high CO2 adsorption capacity, low regeneration energy, good cycle performance, and moisture resistance have been focused on. This article summarizes the optimization of CO2 adsorption by porous adsorption materials and then applies them to the field of CO2 adsorption. The internal laws between the pore structure, surface chemistry, and CO2 adsorption performance of porous adsorbent materials are discussed. Further development requirements and research focus on porous adsorbent materials for CO2 treatment in industrial waste gas are prospected. The structural design of porous carbon adsorption materials is still the current research focus. With the requirements of applications and environmental conditions, the integrity, mechanical strength and water resistance of high-performance materials need to be met

Research and Application of Capacitive Power Transfer System: A Review

Capacitive power transfer (CPT) uses an electric field as the transfer medium to achieve wireless power transfer (WPT). Benefitting from the low eddy current loss, simple system structure and strong plasticity of the coupling coupler, the CPT system has recently gained much attention. The CPT system has significantly improved transfer power, system efficiency, and transfer distance due to continuous research and discussion worldwide. This review briefly presents the basic working principle of the CPT system and summarizes the theoretical research in four aspects, including coupling coupler and high-frequency power converter. Following this, the review focuses on research in six key directions, including system modelling and efficiency optimization. The application of CPT technology in five fields, including medical devices and transportation, is also discussed. This review introduces the progress of CPT research in recent years, hoping to serve as a reference for researchers, to promote the further research and application of the CPT system

Spatiotemporal Variations in Particulate Matter and Air Quality over China: National, Regional and Urban Scales

Ambient exposure to particulate matter (PM) air pollution is known to have an adverse effect on public health worldwide. Rapid increase rates of economic and urbanization, industrial development, and environmental change in China have exacerbated the occurrence of air pollution. This study examines the temporal and spatial distribution of PM on national, regional and local scales in China during 2014–2016. The relationships between the PM2.5 concentration rising rate (PMRR) and meteorological parameters (wind speed and wind direction) are discussed. The dataset of Air Quality Index (AQI), PM10 (PM diameter < 10 μm ) and PM2.5 (PM diameter < 2.5 μm) were collected in 169, 369, and 367 cities in 2014, 2015, and 2016 over China, respectively. The results show that the air quality has been generally improved on the national scale, but deteriorated locally in areas such as the Feiwei Plain. The northwest China (NW) and Beijing-Tianjin-Hebei (BTH) regions are the worst areas of PM pollution, which are mainly manifested by the excessive PM10 caused by blowing dust in spring in NW and the intensive emissions of PM2.5 in winter in BTH. With the classified seven geographic regions, we demonstrate the significant spatial difference and seasonal variation of PM concentration and PM2.5/PM10 ratio, which indicate different emission sources. Furthermore, the dynamic analysis of the PM2.5 pollution process in 11 large urban cities shows dramatic effects of wind speed and wind direction on the PM2.5 loadings

Research and Application of Capacitive Power Transfer System: A Review

Capacitive power transfer (CPT) uses an electric field as the transfer medium to achieve wireless power transfer (WPT). Benefitting from the low eddy current loss, simple system structure and strong plasticity of the coupling coupler, the CPT system has recently gained much attention. The CPT system has significantly improved transfer power, system efficiency, and transfer distance due to continuous research and discussion worldwide. This review briefly presents the basic working principle of the CPT system and summarizes the theoretical research in four aspects, including coupling coupler and high-frequency power converter. Following this, the review focuses on research in six key directions, including system modelling and efficiency optimization. The application of CPT technology in five fields, including medical devices and transportation, is also discussed. This review introduces the progress of CPT research in recent years, hoping to serve as a reference for researchers, to promote the further research and application of the CPT system

Flow structure and heat transfer characteristics of a 90°-turned pin-finned wedge duct with dimples at different locations

In this study, numerical simulations are performed to investigate the effect of dimple location on the flow structure and heat transfer characteristics in a 90°-turned channel with pin fins. Results of the flow structure, heat transfer on the endwall, and friction factor are included in this study. It is found that the dimple location has an impact on the flow structure and heat transfer both for the pin fins arranged with in-line and staggered layout. The horseshoe vortex near the pin fin is influenced by the location of the dimple. The dimple enhances the Nusselt number on the endwall surface significantly. In addition, the dimple location has an effect on the low-speed recirculation, impingement, and vortex which are generated by the dimple. However, the dimple has very limited effects on the friction factor for all cases. It is also found that the area goodness factor and volume goodness factor are improved by the dimple

Computational investigation of curvature effects on jet impingement heat transfer at internally cooled turbine vane leading edge regions

This study is carried out by using numerical simulations to investigate the effect of target surface curvature and the nozzle-to-target surface distance on the flow structure and heat transfer characteristics in a pin-finned double-wall cooling structure. The flow is directly impinging on the target surface and is disturbed by the pin fins, and then released from the film holes after passing the double-wall chamber. The ratio between the radius of the concave outer surface and the chord length of the concave outer surface is varied from 0.500 to 1.300 and the ratio between nozzle-to-target surface distance and diameter of impingement hole is ranging from 0.5 to 2.0. The Reynolds number is between 10,000 and 50,000. Results of the flow structure in the chamber, heat transfer on the target surface, and friction factor of the pin-fi nned channel are included. It is found that an increase of the target surface curvature has signifi cant effects on the flow structure and thus the heat transfer on the target surface is augmented. The Taylor-Görtler vortices near the pin fins are also influenced by the target surface curvature. On the other hand, the nozzle-to-target surface distance influences the jet impingement and the vortices, which are generated by the curvature, remarkably. It is found that the area goodness factor and volume goodness factor are improved by the surface curvature