Diabetes mellitus (DM) is a chronic endocrine disease resulted from insulin secretory defect or insulin resistance and it is a leading cause of death around the world. The care of DM patients ...consumes a huge budget due to the high frequency of consultations and long hospitalizations, making DM a serious threat to both human health and global economies. Tea contains abundant polyphenols and caffeine which showed antidiabetic activity, so the development of antidiabetic medications from tea and its extracts is increasingly receiving attention. However, the results claiming an association between tea consumption and reduced DM risk are inconsistent. The advances in the epidemiologic evidence and the underlying antidiabetic mechanisms of tea are reviewed in this paper. The inconsistent results and the possible causes behind them are also discussed.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
What Else Can CD39 Tell Us? Zhao, Hai; Bo, Cong; Kang, Yan ...
Frontiers in immunology,
06/2017, Volume:
8
Journal Article
Peer reviewed
Open access
As the rate-limiting enzyme in ATP/ADP-AMP-adenosine pathway, CD39 would be a novel checkpoint inhibitor target in preventing adenosine-triggered immune-suppressive effect. In addition, CD39
Tregs, ...but not CD25
Tregs, exhibit sustained Foxp3 levels and functional abilities, indicating it could represent a new specific marker of Tregs. Similarly, inhibition of CD39 enzymatic function at the surface of tumor cells alleviates their immunosuppressive activity. Far from conclusive, present research revealed that CD39 also dephosphorylated and thus inactivated self- and pathogen-associated phosphoantigens of Vγ9Vδ2 T cells, which may be the most promising subpopulation for cellular vaccine. CD39 is also tightly related to Th17 cells and can be regarded as a Th17 cells marker. In this review, we focus on present research of CD39 ectoenzyme and provide insights into its clinical application.
Determination of optimal cutting parameters is one of the most essential tasks in process planning of sculptured parts to reduce machining cost and increase surface quality. This paper presents a ...multi-objective optimization approach, based on neural network, to optimize the cutting parameters in sculptured parts machining. An optimization mathematical model is first presented with spindle speed, feed rate, depth of cut and path spacing as the process parameters and machining time, energy consumption and surface roughness as objectives. Then a Back propagation neural network (BPNN) model is developed to predict cutting parameter, and experiments are designed to train and test the validation of developed BPNN model. Finally, an application case is given and its results demonstrate the ability of our method through comparing with the traditional approach.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
As one of the detectors with superior performances, the Compton continuum in the spectra of the Cerium-doped Lanthanum 3-Bromide (LaBr3:Ce) detector should be suppressed for better performances. A ...compacted LaBr3:Ce/NaI:Tl phoswich detector has been designed to reduce the Compton continuum and improve the peak-to-total (P/T) ratio of the photopeaks. The LaBr3:Ce scintillator is surrounded by a well-type NaI:Tl scintillator and is coupled to a single photomultiplier tube (PMT). The Compton continuum is reduced by identifying the gamma-ray energy depositions in different scintillators using the real-time rise time discrimination (RTD) method. A Geant4 code with actual geometry was performed to simulate the suppressed and unsuppressed spectra. The peak efficiency of total energy at 1332 keV and 662 keV is 1.58% and 2.75%, the peak to total ratio at 137Cs point source and 60Co point source are 0.545 and 0.367, respectively. The reduction of the Compton continuum and the improvement of the P/T ratio will greatly expand the application range of the LaBr3: Ce detector in low-intensity measurements.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Nitrate (NO3−) has become recognized as the most important water-soluble ion in fine particulate (PM2.5), and has been proposed as a driving factor for regional haze formation. However, nitrate ...formation mechanisms are still poorly understood. In this study, PM2.5 samples were collected from September 2017 to August 2018 in Shijiazhuang, a city located on the North China Plain, and NO3−concentration, δ18O-NO3− and δ15N-NO3− values in PM2.5 were analyzed. NO3− concentrations increased as PM2.5 levels increased during both polluted and non-polluted days over the entire year. δ18O-NO3− values during cold months (63.5–103‰) were higher than those during warm months (50.3–85.4‰), these results suggested that the nitrate formation pathways shifted from the NO2 + OH (POH) in warm months to the N2O5 + H2O (PN2O5) and NO3 + VOCs (PNO3) pathways in cold months. Especially during cold months, δ18O-NO3− values increased from 65.2–79.9‰ to 80.7–96.2‰ when PM2.5 increased from ∼25 to >100 μg/m3, but when PM2.5 > 100 μg/m3, there were relatively small variations in δ18O-NO3−. These results suggested that nitrate formation pathways changed from POH to PN2O5 and PNO3 pathways when PM2.5 < 100 μg/m3, but that PN2O5 and PNO3 dominated nitrate production when PM2.5 > 100 μg/m3. Higher δ15N-NO3− values in warm months (−11.8–13.8‰) than in cold months (−0.7–22.6‰) may be attributed to differences in NOx emission sources and nitrogen isotopic fractionation among NOx and NO3−. These results provide information on the dual isotopic compositions of nitrate to understand nitrate formation pathways under different PM2.5 levels.
•One-year values of δ18O-NO3− and δ15N-NO3− in PM2.5 were analyzed in Shijiazhuang.•Seasonal variations in δ18O-NO3− were affected by various nitrate formation pathways.•NO3− production shifted from POH to PN2O5+NO3 in cold months with increased PM2.5•Seasonal δ15N-NO3− was regulated by NOx sources and nitrogen isotopic fractionation.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
An entrance window surrounded phoswich design of GAGG:Ce/CsI:Tl has been implemented for a low-background and Compton-suppressed detector. Not as the common phoswich detector does, the GAGG:Ce ...scintillator with the well-type CsI:Tl scintillator entrance window surrounded makes the efficient large-angle Compton suppression. This design also makes results measured by the phoswich detector have no degradation compared with the single GAGG:Ce detector. The Compton continuum and other backgrounds are reduced by identifying the gamma-ray energy depositions in different scintillators using the real-time rise time discrimination (RTD) method. The background rate is suppressed approximately 74%. The peak-to-total (P/T) ratio at 137Cs and 60Co point sources are 0.769 and 0.561, respectively. The Compton suppression is highly efficient at all the energy range of Compton continuums. The reduction of the Compton continuum and other backgrounds and the improvement of the P/T ratio will greatly expand the application range of the GAGG:Ce detector in low-intensity measurements.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The LaBr
3
(Ce) detector has attracted much attention in recent years because of its superior characteristics compared with other scintillating materials in terms of resolution and efficiency. ...However, it has a relatively high intrinsic background radiation because of the naturally occurring radioisotopes in lanthanum, actinium, and their daughter nuclei. This limits its applications in low-counting rate experiments. In this study, we identified the radioactive isotopes in the
ϕ
3
′
′
×
3
′
′
Saint-Gobain B380 detector by a coincidence measurement using a Clover detector in a low-background shielding system. Moreover, we carried out a Geant4 simulation of the experimental spectra to evaluate the activities of the main internal radiation components. The total activity of the background radiation of B380 is determined to be 1.523 (34) Bq/cm
3
. The main sources include
138
La at 1.428 (34) Bq/cm
3
,
207
Tl at 0.0135 (13) Bq/cm
3
,
211
Bi at 0.0136 (15) Bq/cm
3
,
215
Po at 0.0135 (3) Bq/cm
3
,
219
Rn at 0.0125 (12) Bq/cm
3
,
223
Fr at 0.0019 (11) Bq/cm
3
,
223
Ra at 0.0127 (10) Bq/cm
3
,
227
Th at 0.0158 (22) Bq/cm
3
, and
227
Ac at 0.0135 (13) Bq/cm
3
. Of these, the activities of
207
Tl,
211
Po,
215
Po,
223
Fr, and
227
Ac are deduced for the first time from the secular equilibrium established in the decay chain of
227
Ac.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In order to improve the mechanical strength and imprinting efficiency, a novel bovine serum albumin (BSA) molecularly imprinted poly(ionic liquid)/calcium alginate composite cryogel membrane (MICM) ...was prepared. The results of the tensile test indicated that the MICM had excellent mechanical strength which could reach up to 90.00 KPa, 30.30 times higher than the poly (ionic liquid) membrane without calcium alginate; the elongation of it could reach up to 93.70%, 8.28 times higher than the poly (ionic liquid) membrane without calcium alginate. The MICM had a very high welling ratio of 1026.56% and macropore porosity of 62.29%, which can provide effective mass transport of proteins. More remarkably, it had a very high adsorption capacity of 485.87 mg g−1 at 20 °C and 0.66 mg mL−1 of the initial concentration of BSA. Moreover, MICM also had good selective and competitive recognition toward BSA, exhibiting potential utility in protein separation. This work can provide a potential method to prepare the protein-imprinted cryogel membrane with both high mechanical strength and imprinting efficiency.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Non-primary radiation doses to normal tissues from proton therapy may be associated with an increased risk of secondary malignancies, particularly in long-term survivors. Thus, a systematic method to ...evaluate if the dose level of non-primary radiation meets the IEC standard requirements is needed. Approach. Different from the traditional photon radiation therapy system, proton therapy systems are composed of several subsystems in a thick bunker. These subsystems are all possible sources of non-primary radiation threatening the patient. As a case study, 7 sources in the P-Cure synchrotron-based proton therapy system are modeled in Monte Carlo (MC) code: tandem injector, injection, synchrotron ring, extraction, beam transport line, scanning nozzle and concrete reflection/scattering. To accurately evaluate the synchrotron beam loss and non-primary dose, a new model called the torus source model is developed. Its parametric equations define the position and direction of the off-orbit particle bombardment on the torus pipe shell in the Cartesian coordinate system. Non-primary doses are finally calculated by several FLUKA simulations. Main results. The ratios of summarized non-primary doses from different sources to the planned dose of 2 Gy are all much smaller than the IEC requirements in both the 15 cm to 50 cm and 50 cm to 200 cm regions. Thus, the P-Cure synchrotron-based proton therapy system is clean and patient-friendly, and there is no need an inner shielding concrete between the accelerator and patient. Significance. Non-primary radiation dose level is a very important indicator to evaluate the quality of a PT system. This manuscript provides a feasible Monte Carlo procedure for synchrotron-based proton therapy with new beam loss model. Which could help people figure out precisely whether this level complies with the IEC standard before the system put into clinical treatment. What' more, the torus source model could be widely used for bending magnets in
.
Background:
Prostate cancer is a common malignant tumor with a high incidence. MicroRNAs (miRNAs) have been shown to be important post-transcriptional regulators during tumorigenesis. This study ...aimed to explore the effect of miR-144 on PCa proliferation and apoptosis.
Material and Methods:
The expression of miR-144 and EZH2 were examined in clinical PCa tissues. PCa cell line LNCAP and DU-145 was employed and transfected with miR-144 mimics or inhibitors. The correlation between miR-144 and EZH2 was verified by luciferase reporter assay. Cell viability, apoptosis and migratory capacity were detected by CCK-8, flow cytometry assay and wound healing assay. The protein level of EZH2, E-Cadherin, N-Cadherin and vimentin were analyzed by western blotting.
Results:
miR-144 was found to be negatively correlated to the expression of EZH2 in PCa tissues. Further studies identified EZH2 as a direct target of miR-144. Moreover, overexpression of miR-144 downregulated expression of EZH2, reduced cell viability and promoted cell apoptosis, while knockdown of miR-144 led to an inverse result. miR-144 also suppressed epithelial-mesenchymal transition level of PCa cells.
Conclusion:
Our study indicated that miR-144 negatively regulate the expression of EZH2 in clinical specimens and in vitro. miR-144 can inhibit cell proliferation and induce cell apoptosis in PCa cells. Therefore, miR-144 has the potential to be used as a biomarker for predicting the progression of PCa.
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