Energy enhancement of the target surface electron by using a 200 TW sub-picosecond laser.

One order of magnitude energy enhancement of the target surface electron beams with central energy at 11.5 MeV is achieved by using a 200 TW, 500 fs laser at an incident angle of 72° with a prepulse intensity ratio of 5×10-6. The experimental results demonstrate the scalability of the acceleration process to high electron energy with a longer (sub-picosecond) laser pulse duration and a higher laser energy (120 J). The total charge of the beam is 400±20 pC(E>2.7 MeV). Such a high orientation and mono-energetic electron jet would be a good method to solve the problem of the large beam divergence in fast ignition schemes and to increase the laser energy deposition on the target core.

[Significance of serum calprotectin in assessing inflammatory bowel disease activity].

Objective: To investigate the application value of serum calprotectin in assessing the activity of IBD Methods: Eighty-five Crohn's disease(CD) and eighty-five Ulcerative colitis(UC) patients at Suzhou Municipal Hospital(North Branch) from August 2015 to January 2017 were enrolled in this study, and eighty-five healthy subjects were selected as controls. Serum level of calprotectin was determined by ELISA. Correlation of serum calprotectin with clinical features of IBD was analyzed. The diagnostic efficacy for CD and UC were assessed by ROC curve. Results: The level of serum calprotectin was significantly higher in IBD patients than in healthy subjects. Positive correlations were found between serum calprotectin level and CRP, ESR, fecal calprotectin level of IBD(ρ＝0.341, P<0.001；ρ＝0.438, P<0.001；ρ＝0.542, P<0.001，respectively). Besides, positive correlations were found between serum calprotectin level with disease activity index(CDAI or Mayo score) of IBD(ρ＝0.309, P＝0.004；ρ＝0.227, P＝0.036，respectively)．Nevertheless, no correlation was found between serum calprotectin level with location of IBD and disease subtypes(P>0.05)．The area under curve(AUC) of serum calprotectin for diagnosis of CD and UC were 0.946 and 0.906, respectively. Conclusions: Serum level of calprotectin is associated with the activity of IBD. As a result，serum level of calprotectin may has the potential to be served as a clinical index of IBD activity.

[Rheumatoid arthritis involving tibialis posterior tendon: study on the early diagnostic value of power Doppler ultrasonography and comparison with surgery].

Objective: To explore the value of power Doppler ultrasonography (PDUS) in the early diagnosis of tibialis posterior tendon injury induced by rheumatoid arthritis (RA). Method: From January 2014 to December 2015, a total of 48 cases (60 feet) of RA tendinopathy group were selected as the research subjects from Guanghua Hospital; 12 cases(20 feet) of non-RA tendinopathy group and 10 cases (20 feet) of healthy volunteers were selected as control group.The blood flow signals of pannus were observed by PDUS to determine whether the tendon was injured or the degree of the injury. The following indexes were compared and analyzed by Chi-square testing: (1)positive rate of blood flow signal; (2)grade of blood flow signal; (3)spatial distribution of blood flow signal: diffusibility or local. Results: Of 70 cases(100 feet) in the study, the positive blood flow signals were only in the RA(88.3%) and non-RA group(40.0%) .Grade Ⅲ in RA was 20.0%, while this was not observed in non-RA . Grade Ⅱ in RA and non-RA was 36.7% and 10.0% , respectively. There were significant differences in the positive rate and grades between RA and non-RA group (P<0.01). The spatial distribution of blood flow signal in RA was significantly different from that in non-RA. In RA, they can be detected in the whole tendon.However, they were mainly distributed around the scaphoid in non-RA. In this study, three patients with grade Ⅲwere treated with surgery. The intraoperative findings were consistent with the preoperative ultrasound results. Conclusions: PDUS can be used to detect the neovascular formation of tendon synovitis. It can detect the early tendon injury before the appearance of foot deformity induced by RA, which can guide clinical early intervention treatment and prevent the occurrence of deformity and other serious consequences.

Bright betatron X-ray radiation from a laser-driven-clustering gas target.

Hard X-ray sources from femtosecond (fs) laser-produced plasmas, including the betatron X-rays from laser wakefield-accelerated electrons, have compact sizes, fs pulse duration and fs pump-probe capability, making it promising for wide use in material and biological sciences. Currently the main problem with such betatron X-ray sources is the limited average flux even with ultra-intense laser pulses. Here, we report ultra-bright betatron X-rays can be generated using a clustering gas jet target irradiated with a small size laser, where a ten-fold enhancement of the X-ray yield is achieved compared to the results obtained using a gas target. We suggest the increased X-ray photon is due to the existence of clusters in the gas, which results in increased total electron charge trapped for acceleration and larger wiggling amplitudes during the acceleration. This observation opens a route to produce high betatron average flux using small but high repetition rate laser facilities for applications.

Altered expression of hepatic metabolic enzyme and apoptosis-related gene transcripts in human hepatocytes treated with trichloroethylene.

Trichloroethylene (TCE) is a common organic solvent that has been widely used in industrial applications. Hundred cases of allergic reactions occurred after the workers were occupationally exposed to TCE in China in the past decade, but the underlying effector mechanisms of TCE remain unclear. The purpose of the present study is to examine the alteration of hepatic metabolic enzyme gene and apoptosis-related gene messenger RNA (mRNA) expression in L02 human hepatocytes (L02 cells) after treatment with TCE. L02 cells were cultured either with various doses of TCE (0.25, 0.5, 1.0 and 2.0 mmol/L) for 24 h or with a single dose of TCE (1.0 mmol/L) for different time intervals, whereas samples treated with dimethyl sulfoxide served as control. Quantitative real-time polymerase chain reaction analysis was performed to detect the mRNA expression of hepatic metabolic enzyme genes (CYP1A2, CYP3A4 and CYP2E1) and apoptosis-related genes (BAX and BAD). It was found that the transcript levels of hepatic metabolic enzyme genes and apoptosis genes including BAX and BAD were significantly increased after TCE treatment at various doses for 24 h when compared with controls. Additionally, when the cells were treated with a single dose of TCE (1.0 mmol/L) for different periods of time (3, 6, 12 and 24 h), the mRNA expression of these genes also increased significantly compared with control (p < 0.05 or p < 0.01). The conclusion of the study is that TCE could induce alteration of mRNA expression of hepatic metabolic enzyme genes and apoptosis genes, which might be implicated in the effector mechanisms of TCE cytotoxicity in vivo.

Application of a transmission crystal x-ray spectrometer to moderate-intensity laser driven sources.

In the pursuit of novel, laser-produced x-ray sources for medical imaging applications, appropriate instrumental diagnostics need to be developed concurrently. A type of transmission crystal spectroscopy has previously been demonstrated as a survey tool for sources produced by high-power and high-energy lasers. The present work demonstrates the extension of this method into the study of medium-intensity laser driven hard x-ray sources with a design that preserves resolving power while maintaining high sensitivity. Specifically, spectroscopic measurements of characteristic Kα and Kß emissions were studied from Mo targets irradiated by a 100 fs, 200 mJ, Ti: sapphire laser with intensity of 10(17) W/cm(2) to 10(18) W∕cm(2) per shot. Using a transmission curved crystal spectrometer and off-Rowland circle imaging, resolving powers (E/ΔE) of around 300 for Mo Kα(2) at 17.37 keV were obtained with an end-to-end spectrometer efficiency of (1.13 ± 0.10) × 10(-5). This sensitivity is sufficient for registering x-ray lines with high signal to background from targets following irradiation by a single laser pulse, demonstrating the utility of this method in the study of the development of medium-intensity laser driven x-ray sources.

Spectrally peaked electron beams produced via surface guiding and acceleration in femtosecond laser-solid interactions.

Highly collimated MeV electron beam guiding has been observed along the target surface following the interaction of bulk target irradiation by femtosecond laser pulses at relativistic intensities. The beam quality is shown to depend critically on the laser contrast: With a ns prepulse, the generated electron beam is well concentrated and intense, while a high laser contrast produces divergent electron beams. In the case of large preplasma scale lengths, tunable guiding and acceleration of the target surface electrons is achieved by changing the laser incident angle. By expanding the preplasma scale length to several hundred micrometers, we obtained MeV spectrum-peaked electron beams with a 100 pC per laser pulse and divergence angles of only 3°. This technique suggests a stable method of injection of elections into a variety of accelerator designs.

Intense high-contrast femtosecond K-shell x-ray source from laser-driven Ar clusters.

Bright Ar quasimonochromatic K-shell x ray with very little background has been generated using an Ar clustering gas jet target irradiated with a 30 fs ultrahigh-contrast laser, with a measured flux of 2.2×10(11) photons/J into 4π. This intense x-ray source critically depends on the laser contrast and intensity. The optimization of source output with interaction length is addressed. Simulations point to a nonlinear resonant mechanism of electron heating during the early stage of laser interaction, resulting in enhanced x-ray emission. The x-ray pulse duration is expected to be only 10 fs, opening the possibility for single-shot ultrafast keV x-ray imaging applications.

Expression of hypoxia inducible factor-1α and its significance in laryngeal carcinoma.

This study examined levels of hypoxia inducible factor-1α (HIF-1α) protein in 40 laryngeal squamous cell carcinoma specimens using immunohistochemistry. Correlations between HIF-1α immunoreactivity and patient age, tumour lymph node metastasis stage, histological grade (extent of differentiation), and alcohol and smoking history were evaluated. Of the tumour tissues obtained, 35 (87.5%) were located in the glottic area and five (12.5%) in the supraglottic area. All patients were male and aged between 35 and 71 years; 12 (30.0%) presented with lymph node metastases, 24 (60.0%) had cancer classified as T(1) or T(2), and 16 (40.0%) as high clinical stage (T(3) or T(4)). The pattern of HIF-1α protein localization in tumour tissues, when present, was mixed nuclear/cytoplasmic, with positive HIF-1α expression in 27 patients (67.5%). Differences in HIF-1α levels in samples from different tumour stages and in those with lymph node-positive versus lymph node-negative cancers were statistically significant.