Intestinal epithelial cells (IEC) act as an important intestinal barrier whose function can be impaired upon induction by hypoxia. Although intestinal barrier injuries are preventable by milk-derived ...exosomal microRNAs (miRNAs), the underlying mechanism remains poorly understood. This study aimed to characterize the effect of yak and cow milk–derived exosomal miRNA on the barrier function of IEC-6 under hypoxic conditions, and explore the mechanism of yak milk exosomal miRNA to relieve the hypoxia stress. First, by Illumina HiSeq 2500 (Illumina Inc., San Diego, CA) sequencing, the miRNA expression was systematically screened, and differential expression of 130 miRNAs was identified with 51 being upregulated and 79 downregulated in yak and cow milk–derived exosomes. Furthermore, the top 20 miRNAs that had a relatively consistent high expression in yak milk exosome were identified, and bta-miR-34a was found to be an effective regulator for alleviating hypoxic injury of IEC-6. In vitro assay of the role of bta-miR-34a on survival of IEC-6 in hypoxia by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) confirmed its effectiveness to significantly increase IEC-6 survival up to 13% for 12 h, and up to 9.5% for 24 h. Investigation on the regulatory relationship between bta-miRNA-34a and the hypoxia-inducible factor/apoptosis signaling pathway provided insights into the possible mechanisms by which bta-miR-34a activated the hypoxia-inducible factor and apoptosis signaling pathway, thus promoting IEC-6 survival. The results of this study suggest an important relationship between miRNA expression and intestine barrier integrity, which facilitated further understanding of the physiological function of yak and cow milk exosomal miRNAs, as well as mechanisms of hypoxia-driven epithelial homeostasis.
We find that the random fiber laser (RFL) without point-reflectors is a temperature-insensitive distributed lasing system for the first time. Inspired by such thermal stability, we propose the novel ...concept of utilizing the RFL to achieve long-distance fiber-optic remote sensing, in which the RFL offers high-fidelity and long-distance transmission for the sensing signal. Two 100 km fiber Bragg grating (FBG) point-sensing schemes based on RFLs are experimentally demonstrated using the first-order and the second-order random lasing, respectively, to verify the concept. Each sensing scheme can achieve >20 dB optical signal-to-noise ratio (OSNR) over 100 km distance. It is found that the second-order random lasing scheme has much better OSNR than that of the first-order random lasing scheme due to enhanced lasing efficiency, by incorporating a 1455 nm FBG into the lasing cavity.
A dual-polarized broadband coupled feed dipole antenna loaded with artificial magnetic conductor (AMC) structure is proposed. The proposed AMC structure with 4×4 elements shown in this paper consists ...of four perfect electrical conductor (PEC) rectangular strips and a ring to reduce the profile height of the dual-polarized dipole antenna. In addition, the dual-polarization antenna adopts coupling feed microstrip to excite two pairs of bow-tie patch. The overall size of the coupling feed dipole antenna is 1.1λ0×1.1λ0×0.09λ0 at 5.5 GHz. Measured results shows that the proposed dual-polarization antenna loaded AMC exhibit a 25.2% common working bandwidth (4.75-6.12 GHz). The isolation is less than -14 dB, and the peak gain is 10.6 dBi. This dipole antenna with AMC structure has the virtues of low profile, wide band, and good radiation performance and it has the potential to be used in C-band communication.
A study conducted by Jia et presenting an experimental investigation on shear creep properties of undisturbed rock discontinuity in Baihetan Hydropower Station is discussed. They states that the ...experimental results of shear creep tests on rock discontinuity indicate that much more attention should be payed to the monitor of stress and displacement in the fault zones. The empirical equation proposed in the study can be used to estimate the creep strain. Appropriate creep constitutive model will be proposed in the future work based on our experimental data and the model will be utilized to evaluate the long term stability and safety of Baihetan dam foundation.
The grouper, Epinephelus lanceolatus, is a vulnerable species of high economic value. An effective protocol was developed for the cryopreservation of E. lanceolatus by comparing different extenders ...produced by mixing various cryoprotectants (dimethyl sulfoxide, methanol and glycerol) and diluents (MPRS, TS‐2, TS‐19, Cortland and Hank's). Using computer‐assisted sperm analysis (CASA) and morphological analysis, the sperm motility and fertilization rates from post‐thaw sperm were comparable to untreated controls. The results revealed that MPRS (containing 12% DMSO) or TS‐19 (containing 12% DMSO), were the optimum extenders for protecting the sperm from cryo‐damage in liquid nitrogen. The post‐thaw sperm maintained high motility (90.61 ± 3.03%) and a fertilization rate (92.27 ± 2.43%) similar (P > 0.05) to fresh sperm (94.34 ± 4% and 94.10 ± 1.87%). This study is the first to report on the successful sperm cryopreservation of E. lanceolatus and provides an important tool for repopulating this species through aquaculture.
Abstract Objective To analyze the clinical characteristics, risk factors, and prevention of de novo malignant tumors after liver transplantation. Methods Fourteen patients who underwent liver ...transplantation were identified as having de novo malignancies. The clinical characteristics and survival of these patients were retrospectively reviewed. Results Fourteen cases of de novo malignancies after liver transplantation occurred for an incidence rate of 1.94% (14/722), including 11 men (78.6%, mean age, 48 y) and 3 women (21.4%, mean age, 50 y). The mean period from transplantation to cancer diagnosis was 55 ± 35 months. The distribution of tumor histologic types included colon cancer, lung cancer, esophageal cancer, nasopharyngeal cancer, liver cancer, parotid carcinoma, bone cancer, post-transplantation lymphoproliferative disorder, stomach cancer, bladder cancer, and laryngeal cancer. Twelve cases (85.7%) had hepatitis B. Five patients (35.7%) underwent operations, and the other 9 patients underwent chemotherapy or radiotherapy. During a mean follow-up period of 37 ± 26 months after the diagnosis of de novo malignancy, 8 patients (57.1%) died, with only 1 dying of causes not related to the de novo malignancy. The survival analysis showed 1-, 5-, and 7-year survival rates of 85.7%, 71.4%, and 42.9%, respectively. Conclusions De novo malignancies after organ transplantation have been suggested to be a major cause of late mortality. De novo malignancy after orthotopic liver transplantation was found to be related to smoking, sex, and low immune function due to immunosuppressive agents. Solid tumors should be removed, and the patient should receive chemotherapy or radiotherapy as early as possible. Early diagnosis and treatment are very important for improving the prognosis.
A regulator of the protein phosphatase 2A (PP2A), α4, has been implicated in a variety of functions that regulate many cellular processes. To explore the role of α4 in human cell transformation and ...tumorigenesis, we show that α4 is highly expressed in human cells transformed by chemical carcinogens including benzo(a)pyrene, aflatoxin B(1), N-methyl-N'-nitro-N-nitrosoguanidine, nickel sulfate and in several hepatic and lung cancer cell lines. In addition, overexpression of α4 was detected in 87.5% (74/80) of primary hepatocellular carcinomas, 84.0% (21/25) of primary lung cancers and 81.8% (9/11) of primary breast cancers, indicating that α4 is ubiquitously highly expressed in human cancer. Functional studies revealed that elevated α4 expression results in an increase in cell proliferation, promotion of cell survival and decreased PP2A-attributable activity. Importantly, ectopic expression of α4 permits non-transformed human embryonic kidney cells (HEKTER) and L02R cells to form tumors in immunodeficient mice. Furthermore, we show that the highly expressed α4 in transformed cells or human tumors is not regulated by DNA hypomethylation. A microRNA, miR-34b, that suppresses the expression of α4 through specific binding to the 3'-untranslated region of α4 is downregulated in transformed or human lung tumors. Taken together, these observations identify that α4 possesses an oncogenic function. Reduction of PP2A activity due to an enhanced α4-PP2A interaction contributes directly to chemical carcinogen-induced tumorigenesis.
We have developed a field-effect transistor (FET) device using a solid ion conductor (SIC) as the gate dielectric, which can tune the carrier density of FeSe by driving lithium ions in and out of the ...FeSe thin flakes and consequently control the physical properties and phase transitions. A dome-shaped superconducting phase diagram was mapped out with increasing Li content, with Tc~46.6 K for optimal doping, and an insulating phase was reached at the extremely overdoped regime. Our study suggests that, by using a solid ion conductor as the gate dielectric, the SIC-FET device is able to induce much higher carrier doping in the bulk, suit many surface-sensitive experimental probes, and stabilize structural phases that are inaccessible in ordinary conditions.
Dust storms have direct or indirect impacts on climate change and human health. Identifying and quantifying natural/anthropogenic dust sources can facilitate effective prevention and control of dust ...events. Based on surface real-time PM10 monitoring data, satellite remote sensing and the HYSPLIT model, this study determined the specific timing, coverage and sources of dust events in Shanxi Province, Northern China. Thus, a composite fingerprinting technique was established to quantify potential dust sources and dust contributions of single dust events. The dust oxidation model was validated, indicating that the composite fingerprinting technique was well suited to the study region. The results show that natural dust sources (67%) contributed more to the study region than anthropogenic dust sources. They were mainly from the northwest and north of the study region. Particularly, the contributions of Taiyuan (TY) and Linfen (LF) accounted for the largest (82%) and smallest (55%) proportions, respectively, both exceeding 50%. Anthropogenic dust sources contributed 33%, mainly from the east and south of the study region. The contribution of anthropogenic dust sources increased in the study region from north to south. In terms of potential dust sources, the Tengger Desert and Badain Jaran Desert (TDBD) contributed the most (26%), followed by the Otindag Sandy Land (OL) (22%). The Taklimakan Desert (TD) contributed the least (2%). The Middle Farmland region of the Hexi Corridor (HMF) in the west (15%) had the largest proportion of anthropogenic dust sources. Differences in the regional contribution of potential dust sources mainly resulted from winter winds, surface drought severity and particle size. At an insignificant distance from the study region, the contribution of potential dust sources was larger in the west than in the east and increased from south to north overall. These methods and findings can contribute to improving the ecological environment in Northern China.
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•Composite fingerprinting can effectively quantify the contribution of dust sources.•Natural dust sources contribute about 67% of the dust to the study region.•TDBD (26%) and OL (22%) are the main natural dust sources, with high contributions.•HMF is the main anthropogenic dust source, accounting for about 16%.
A combination of scanning electron microscopy and electron backscatter diffraction is used to investigate the deformation in the fatigue crack tip plastic zone and its role in the crack propagation ...of Ti-6Al-2Zr-1Mo-1V alloy with a tri-modal microstructure. The results show that heterogenous slip and secondary micro-cracks are the main features of the fatigue crack tip plastic zone. These features play important roles in fatigue crack propagation. In particular, the unique lamellar α in the tri-modal microstructure can deflect and delay the crack propagation effectively, thus, improving the fatigue life.
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