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An efficient plasma compression scheme using azimuthally polarized light is proposed. Azimuthally polarized light possesses a donutlike intensity pattern, enabling it to compress and accelerate ions toward the optical axis across a wide range of parameters. When the light intensity reaches the relativistic regime of 10^{18}W/cm^{2}, and the plasma density is below the critical density, protons can be compressed and accelerated by the toroidal soliton formed by the light. The expansion process of the soliton can be well described by the snowplow model. Three-dimensional particle-in-cell simulations show that within the soliton regime, despite the ion density exceeding ten times the critical density, the ions' energy is insufficient for efficient neutron production. When the light intensity increases to 10^{22}W/cm^{2}, and the plasma density reaches several tens of times the critical density, deuterium ions can be compressed to thousands of times the critical density and simultaneously accelerated to the MeV level by tightly focused azimuthally polarized light during the hole-boring process. This process is far more dramatic compared to the soliton regime and can produce up to 10^{4} neutrons in a few light cycles. Moreover, in the subsequent beam-target stage, neutron yield is estimated to exceed 10^{8}. Finally, we present a comparison with the results obtained using a radially polarized light to examine the influence of light polarization.
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Background: In China, Oldenlandia diffusa (OD) has been prescribed as a therapeutic herb for rheumatoid arthritis (RA). We previously conducted a preliminary study of the anti-inflammatory effect of OD, and the purpose of this study is to further investigate its mechanism. Methods: We performed a quantitative proteomic analysis of synovium, identified the differentially expressed proteins, and performed bioinformatics analyses. With the help of network pharmacology, we aimed to find the key synovial proteins which OD or its key compound might influence. To verify the result, liquid chromatography-mass spectrometry (LC-MS) was applied to quantify and qualify the absorbable potential compounds of OD. The anti-inflammatory effect was evaluated by morphological, histopathological, and cytokine analyses. Target proteins were observed by immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA). Results: MMP3 and CAV1 were identified as 2 of the differentially expressed proteins in RA synovium, and might be influenced by quercetin, the active compound of OD. MMP3 might be altered through atherosclerosis signaling, while CAV1 might be altered through caveolar-mediated endocytosis signaling. According to our verification, quercetin was identified as the absorbed and effective compound of OD, and it could exert an anti-inflammatory effect on the collagen-induced arthritis (CIA) model, including serum cytokine expression, synovial hyperplasia and lymphocyte infiltration, articular cartilage lesion. Quercetin could also down-regulate the synovial expression of MMP3 and CAV1, and could exert better effects at a high dose. Conclusions: Quercetin was the main active compound of OD in the treatment of RA. OD might alleviate inflammatory responses in CIA rats by suppressing the expression of MMP3 and CAV1 through quercetin, and at a high dose, quercetin could exert a better anti-inflammatory effect.
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An organocatalytic vinylogous Michael addition triggered triple-cascade reaction has been developed. 2-Hydroxycinnamaldehydes worked under iminium activation with either acyclic or cyclic ketone-derived α,α-dicyanoalkenes, yielding the benzofused oxabicyclo[3.3.1]nonanes bearing one quaternary stereocenter with excellent stereoselectivities.
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The asymmetric organocatalytic cascade reaction of cyclic ß-oxo aldehydes to 2-hydroxycinnamaldehydes is developed. The bifunctional tertiary amine-thiourea catalyst was used in a rationally designed multiple catalysis where the asymmetric iminium catalysis and thiourea anion-binding catalysis were combined by carboxylate anion as a ternary catalytic system to form a quinary catalyst-substrate complex, providing an efficient protocol for the construction of enantioenriched spiro-bridged or cagelike polyheterocyclic compounds. The reuse of catalysts was also successfully realized.
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We study x-ray production by coherent nonlinear Thomson scattering of few-cycle laser pulses from relativistic electron sheets. For an electron sheet thicker than the wavelength of the x-ray, the scattering efficiency is found to increase by two orders of magnitude for single-cycle laser pulses, as compared with longer pulses. This enhancement is attributed to the suppression of the destructive interference during the scattering process, as well as the frequency downshift related to the ultrabroad spectra of single-cycle pulses. The x-ray amplitude in this nonadiabatic regime is calculated and agrees with that from the particle-in-cell simulation. These results can be useful for designing more intense, shorter attosecond x-ray sources.
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Betulinic acid is a naturally occurring pentacyclic triterpenoid, which has antiretroviral, antimalarial, and anti-inflammatory properties. The purpose of this study is to investigate the HBV DNA replication inhibition in the mouse model with betulinic acid. Hydrodynamic injection method via the tail vein with the Paywl. 3 plasmid was used to establish the animal mode (n = 15), and the mice were randomly divided into the PBS control group (n = 5), Betulinic acid treatment group (n = 5) and lamivudine control group (n = 5). The day after successful modeling , the mice would have taken Betulinic acid (100 mg x kg(-1)), lamivudine (50 mg x kg(-1)), PBS drugs orally, once daily for 7 days, blood samples were acquired from the orbital venous blood at 3, 5, 7 days after the administering, HBsAg and HBeAg in serum concentration were measured by ELISA and the mice were sacrificed after 7 days, HBV DNA southern detections were used with part of mice livers. The results showed that betulinic acid significantly inhibited the expression of HbsAg in the mice model at the fifth day compared with the control group, and there was no significant differences between the effects of lamivudine and the PBS control group; both the betulinic acid and lamivudine groups had no significant inhibition for the HBeAg expression; the HBV DNA expressions of the liver tissue from the betulinic acid and lamivudine groups were inhibited compared with the control group. Taken together, these results reveal betulinic acid can inhibit the HBsAg expression and replication of the liver HBV DNA in the mouse model.
Sujet(s)
Antiviraux/pharmacologie , ADN viral/biosynthèse , Virus de l'hépatite B/génétique , Virus de l'hépatite B/physiologie , Hépatite B/virologie , Plasmides/génétique , Triterpènes/pharmacologie , Maladie aigüe , Animaux , Réplication de l'ADN/effets des médicaments et des substances chimiques , Hépatite B/sang , Antigènes de surface du virus de l'hépatite B/sang , Virus de l'hépatite B/effets des médicaments et des substances chimiques , Virus de l'hépatite B/immunologie , Mâle , Souris , Triterpènes pentacycliques , Réplication virale/effets des médicaments et des substances chimiques , Acide bétuliniqueRÉSUMÉ
We propose a scheme to generate single-cycle powerful terahertz (THz) pulses by ultrashort intense laser pulses obliquely incident on an underdense plasma slab of a few THz wavelengths in thickness. THz waves are radiated from a transient net current driven by the laser ponderomotive force in the plasma slab. Analysis and particle-in-cell simulations show that such a THz source is capable of providing power of megawatts to gigawatts, field strength of MV/cm-GV/cm, and broad tunability range, which is potentially useful for nonlinear and high-field THz science and applications.
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BACKGROUND: A wide array of proteins is secreted into the bile and may be associated with biliary tract diseases. We attempted to discover novel biomarker in bile for cholangiocarcinoma. METHODS: Bile was collected from patients with bile duct obstruction. Proteins were separated by 2-dimensional electrophoresis and identified by mass spectrometry. Levels of mRNA and protein expression of the candidate biomarker were analyzed by real-time PCR and Western blotting, respectively, whereas enzyme activity was measured by a kinetic method. The diagnostic efficacy was assessed by receiver operating characteristic (ROC) curve analysis. RESULTS: Pancreatic elastase (PE) 3B was identified as a biomarker for cholangiocarcinoma. The mRNA of PE 3B was up-regulated in cancerous tissues, compared to non-cancerous tissues. The protein expression and enzyme activity of PE in bile were increased in patients with cholangiocarcinoma, compared to gallstone patients. Biliary amylase activity was used to correct the presence of pancreaticobiliary reflux. Significantly higher PE/amylase ratios in bile were found in patients with cholangiocarcinoma (0.214+/-0.045) than those with gallstone (0.023+/-0.005, p<0.001). The area under the ROC curve of the ratio was 0.877 (95% CI: 0.765 to 0.988). Using 0.065 as a cutoff value, the ratio distinguished malignant from benign causes of biliary obstruction with a sensitivity of 82% and a specificity of 89%. CONCLUSION: PE in bile is a biomarker for cholangiocarcinoma and the combination measurement of PE and amylase enhances diagnostic efficacy.
Sujet(s)
Voies biliaires/enzymologie , Cholangiocarcinome/diagnostic , Cholestase/complications , Pancreatic elastase/métabolisme , Séquence nucléotidique , Cholangiocarcinome/complications , Amorces ADN , HumainsRÉSUMÉ
The acceleration of ions in collisionless electrostatic shocks and solitary waves, driven by ultrashort intense laser pulses in a thin solid target under different conditions, is investigated theoretically. When a shock is formed, ions with certain initial velocities inside the target can be accelerated by the electrostatic field at the shock front to twice the shock speed. When a solitary wave is formed, only ions located at the rear surface of the target can be accelerated by the solitary wave together with the sheath field formed there.
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Powerful coherent terahertz (THz) pulses with a broad spectrum (0.1-3 THz) can be produced from a laser-driven wakefield through linear mode conversion in inhomogeneous magnetized plasmas with the maximum plasma density of 10(17) cm(-3). This occurs when a laser pulse, with an optimized duration about 300 fs, is incident either normally or obliquely to the density gradient of inhomogeneous magnetized plasmas. The external dc magnetic field has a magnitude of a few tesla. By changing the strength and direction of the magnetic field, one can enhance or suppress the THz emission. The maximum energy conversion efficiency in the magnetized plasmas can be double that in the unmagnetized plasmas. Such wakefield emission can be a powerful THz source at the MW level and capable of affording field strength of a few MV/cm, suitable for THz nonlinear physics. Because these THz emissions are always with a positive chirp, with a proper dispersion compression, single-cycle THz pulses can be generated with higher peak powers and field strengths.
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BACKGROUND/OBJECTIVES: Elevated concentrations of Hepatocarcinoma-Intestine-Pancreas/Pancreatitis-associated Protein I (HIP/PAP-I) in pancreatic juice have been reported in patients with pancreatic adenocarcinoma and have been considered as a promising tumor marker. This study was conducted to investigate whether biliary HIP/PAP-I can be used in the differential diagnosis of the cause of biliary obstruction. METHODS: Bile was obtained from patients with bile duct obstruction on the day of biliary drainage. The etiology of biliary obstruction included gallstones (n = 131), pancreatic cancer (n = 32), cholangiocarcinoma (n = 47), papilla Vater cancer (n = 13), hepatocellular carcinoma (n = 4) and metastatic cancer (n = 16). In addition to HIP/PAP-I, the samples were analyzed for amylase to check for the presence of pancreaticobiliary reflux. RESULTS: The biliary concentration of HIP/PAP-I was not statistically different between patients with gallstones (median, 9.70 ng/mL; interquartile range [IQR] 1.80-45.75) and cancers (median, 12.70 ng/mL; IQR, 3.85-36.75), P > 0.05. However, the amylase activity in the bile was markedly elevated in patients with gallstones (median, 228 U/L; IQR, 40-1965), compared to those with cancer (median, 32 U/L; IQR; 30-176), P < 0.001. The area under the ROC curve of amylase was 0.751 (95% CI: 0.69 to 0.81). At a cut-off value of 46 U/L, the biliary amylase distinguished patients with malignant obstruction from those with benign obstruction with a sensitivity of 66% and a specificity of 74%. CONCLUSIONS: Our data suggest that the biliary HIP/PAP-I measurement is not useful for differentiating causes of biliary obstruction. The divergent extent and duration of biliary obstruction caused by neoplasm and gallstones may contribute to the significant difference in the amylase activity in bile. Thus, amylase in bile represents a candidate marker in the differential diagnosis of the cause of biliary obstruction.
Sujet(s)
Amylases/analyse , Antigènes néoplasiques/analyse , Tumeurs des canaux biliaires/diagnostic , Bile/enzymologie , Marqueurs biologiques tumoraux/analyse , Lectines de type C/analyse , Maladie des voies biliaires/diagnostic , Diagnostic différentiel , Femelle , Humains , Mâle , Protéines associées à la pancréatite , Études rétrospectives , TaïwanRÉSUMÉ
The interaction of two copropagating laser beams with crossed polarization in the underdense plasmas has been investigated analytically with the variational approach and numerically. The coupled envelope equations of the two beams include both the relativistic mass correction and the ponderomotive force effect. It is found that the relativistic effect always plays the role of beam attraction, while the ponderomotive force can play both the beam attraction and beam repulsion, depending upon the beam diameters and their transverse separation. In certain conditions, the two beam centers oscillate transversely around a propagation axis. In this case, the ponderomotive effect can lead to a higher oscillation frequency than that accounting for the relativistic effect only. The interaction of two beams decreases the threshold power for self-focusing of the single beam. A strong self-trapping beam can channel a weak one.
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Coherent terahertz (THz) emission from the vacuum-plasma interface induced through laser wake-field excitation has been investigated by particle-in-cell simulations. The emission frequency appears around tau(-1)(L), where tau(L) is the laser pulse duration, even though the plasma density is distributed inhomogeneously near the interface. The emission amplitude, which is zero on the propagation axis of the incident pulse, increases transversely until reaching the maximum amplitude at the beam edge of the incident pulse and then decays transversely. The emission power scales like P approximately 10(8) x a(4)(0) W, where a(0) is the normalized field amplitude of the laser pulse. For an incident pulse of a few tens of femtoseconds at the forced intensity of 3 x 10(17) W/cm(2), it can generate THz radiation with a power of a few MW and with an energy of several microJ/pulse.