Ergodic Measure and Potential Control of Anomalous Diffusion.

In statistical mechanics, the ergodic hypothesis (i.e., the long-time average is the same as the ensemble average) accompanying anomalous diffusion has become a continuous topic of research, being closely related to irreversibility and increasing entropy. While measurement time is finite for a given process, the time average of an observable quantity might be a random variable, whose distribution width narrows with time, and one wonders how long it takes for the convergence rate to become a constant. This is also the premise of ergodic establishment, because the ensemble average is always equal to the constant. We focus on the time-dependent fluctuation width for the time average of both the velocity and kinetic energy of a force-free particle described by the generalized Langevin equation, where the stationary velocity autocorrelation function is considered. Subsequently, the shortest time scale can be estimated for a system transferring from a stationary state to an effective ergodic state. Moreover, a logarithmic spatial potential is used to modulate the processes associated with free ballistic diffusion and the control of diffusion, as well as the minimal realization of the whole power-law regime. The results presented suggest that non-ergodicity mimics the sparseness of the medium and reveals the unique role of logarithmic potential in modulating diffusion behavior.

Self-Calibration 3D Hybrid SERS Substrate and Its Application in Quantitative Analysis.

Surface-enhanced Raman spectroscopy (SERS) has been widely applied in many fields as a sensitive vibrational fingerprint technique. However, SERS faces challenges in quantitative analysis due to the heterogeneity of hot spots. An internal standard (IS) strategy has been employed for correcting the variation of hot spots. However, the method suffers from limitations due to the competitive adsorption between the IS and the target analyte. In this work, we combined the IS strategy with the 3D hybrid nanostructures to develop a bifunctional SERS substrate. The substrate had two functional units. The bottom self-assembly layer consisted of Au@IS@SiO2 nanoparticles, which provided a stable reference signal and functioned as the calibration unit. The top one consisted of appropriate-sized Au octahedrons for the detection of target analytes, which was the detection unit. Within the 3D hybrid nanostructure, the calibration unit improved the SERS performance of the detection unit, which was demonstrated by the 6-fold increase of SERS intensity when compared with the 2D substrate. Meanwhile, the reproducibility of the detection was greatly improved by correcting the hot spot changes through the calibration unit. Two biomedical molecules of cotinine and creatinine in ultrapure water and artificial urine, respectively, were sensitively determined by the 3D hybrid substrate. We expect that the developed bifunctional 3D substrate will open up new ways to advance the applications of SERS.

Rapid and Simple Analysis of the Human Pepsin Secondary Structure Using a Portable Raman Spectrometer.

Human pepsin is a digestive protease that plays an important role in the human digestive system. The secondary structure of human pepsin determines its bioactivity. Therefore, an in-depth understanding of human pepsin secondary structure changes is particularly important for the further improvement of the efficiency of human pepsin biological function. However, the complexity and diversity of the human pepsin secondary structure make its analysis difficult. Herein, a convenient method has been developed to quickly detect the secondary structure of human pepsin using a portable Raman spectrometer. According to the change of surface-enhanced Raman spectroscopy (SERS) signal intensity and activity of human pepsin at different pH values, we analyze the change of the human pepsin secondary structure. The results show that the content of the ß-sheet gradually increased with the increase in the pH in the active range, which is in good agreement with circular dichroism (CD) measurements. The change of the secondary structure improves the sensitivity of human pepsin SERS detection. Meanwhile, human pepsin is a commonly used disease marker for the noninvasive diagnosis of gastroesophageal reflux disease (GERD); the detection limit of human pepsin we obtained is 2 µg/mL by the abovementioned method. The real clinical detection scenario is also simulated by spiking pepsin solution in saliva, and the standard recovery rate is 80.7-92.3%. These results show the great prospect of our method in studying the protein secondary structure and furthermore promote the application of SERS in clinical diagnosis.

Calcitriol increases MBNL1 expression and alleviates myotonic dystrophy phenotypes in HSALR mouse models.

BACKGROUND: Myotonic dystrophy type 1 (DM1), one of the most common forms of adult-onset muscular dystrophy, is caused by abnormally expanded CTG repeats in the 3' untranslated region of the DMPK gene. The CUG repeats transcribed from the expanded CTG repeats sequestrate a splicing factor, MBNL1, causing the clinical symptoms in DM1. Nowadays, only symptomatic treatments are available for DM1, and no rational therapy is available. Recently, upregulation of MBNL1 expression has been found to be one of the promising therapies for DM1. METHODS: All experiments were conducted in the C2C12 myoblasts and HSALR mice, a DM1 mouse model. Real-time PCR and western blot were used to detect the mRNA and protein level, respectively. The rotarod exercise, grip strength and hanging time were used to evaluate the muscle strength of mice. RESULTS: In this study, we demonstrated that calcitriol, an active form of vitamin D3, increased MBNL1 in C2C12 mouse myoblasts as well as in HSALR mice model for DM1. In HSALR mice model, calcitriol improved muscle strength, and corrected aberrant splicing in skeletal muscle. Besides, calcitriol reduced the number of central nuclei, and improved muscle histopathology in HSALR mice. In addition, we identified that calcitriol upregulated MBNL1 expression via activating the promoter of Mbnl1 in C2C12 myogenic cells. CONCLUSION: Our study suggests that calcitriol is a potential pharmacological strategy for DM1 that enhances MBNL1 expression.

In Situ Surface-Enhanced Raman Spectroscopy Characterization of Electrocatalysis with Different Nanostructures.

As energy demands increase, electrocatalysis serves as a vital tool in energy conversion. Elucidating electrocatalytic mechanisms using in situ spectroscopic characterization techniques can provide experimental guidance for preparing high-efficiency electrocatalysts. Surface-enhanced Raman spectroscopy (SERS) can provide rich spectral information for ultratrace surface species and is extremely well suited to studying their activity. To improve the material and morphological universalities, researchers have employed different kinds of nanostructures that have played important roles in the development of SERS technologies. Different strategies, such as so-called borrowing enhancement from shell-isolated modes and shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS)-satellite structures, have been proposed to obtain highly effective Raman enhancement, and these methods make it possible to apply SERS to various electrocatalytic systems. Here, we discuss the development of SERS technology, focusing on its applications in different electrocatalytic reactions (such as oxygen reduction reactions) and at different nanostructure surfaces, and give a brief outlook on its development.

Rno_circRNA_008646 regulates formaldehyde induced lung injury through Rno-miR-224 mediated FOXI1/CFTR axis.

Formaldehyde (FA) serves as a prevailing air pollutant, which has seriously threatened public health in recent years. Of all the known health effects, lung injury is one of the most severe risks. However, little is known about the circRNAs related molecular mechanism in the development of lung injury induced by FA. This study was designed to explore the potential roles of dysregulated circRNAs as well as its mechanism in FA-induced lung injury. In the present study, 24 male SD rats were exposed to formaldehyde (control, 0.5, 2.46 and 5 mg/m3) for 8 h per day for 8 weeks to induce lung injury. We used H&E staining to evaluate the histopathological changes of lung injury indifferent groups. The expression of circRNAs in lung tissue was detected by real-time PCR. Meanwhile, circRNA/miRNA/mRNA interaction networks were predicted by bioinformatics analysis. Our study revealed that formaldehyde exposure resulted in abnormal histopathological changes in lung tissues. Moreover, the expression of rno_circRNA_008646 was significantly higher in lung tissues of formaldehyde exposure rats than in control. Bioinformatics analysis showed that one potential target miRNA/mRNA for rno_circRNA_008646 was rno-miR-224/Forkhead Box I1 (FOXI1). Besides, luciferase report gene confirmed that there was targeted binding relationship between rno_circRNA_008646 and rno-miR-224, rno-miR-224 and FOXI1. Further verification experiments indicated that the expression of rno_circRNA_008646 was negatively correlated rno-miR-224, while it was positively correlated with FOXI1. JASPAR database showed transcription factor FOXI1 located in promotor of CF Transmembrane Conductance Regulator (CFTR). Both FOXI1 and CFTR were up-regulated in lung tissues after formaldehyde exposure. In conclusion, our findings suggested that formaldehyde may induce lung injury, and this may be caused by up-regulatedrno_circRNA_008646, which medicated rno-miR-224/FOXI1/CFTR axis.

Probing Electric Field Distributions in the Double Layer of a Single-Crystal Electrode with Angstrom Spatial Resolution using Raman Spectroscopy.

The electrical double layer (EDL) is the extremely important interfacial region involved in many electrochemical reactions, and it is the subject of significant study in electrochemistry and surface science. However, the direct measurement of interfacial electric fields in the EDL is challenging. In this work, both electrochemical resonant Raman spectroscopy and theoretical calculations were used to study electric field distributions in the EDL of an atomically flat single-crystal Au(111) electrode with self-assembled monolayer molecular films. This was achieved using a series of redox-active molecules containing the 4,4'-bipyridinium moiety as a Raman marker that were located at different precisely controlled distances away from the electrode surface. It was found that the electric field and the dipole moment of the probe molecule both directly affected its Raman signal intensity, which in turn could be used to map the electric field distribution at the interface. Also, by variation of the electrolyte anion concentration, the Raman intensity was found to decrease when the electric field strength increased. Moreover, the distance between adjacent Raman markers was ∼2.1 Å. Thus, angstrom-level spatial resolution in the mapping of electric field distributions at the electrode-electrolyte interface was realized. These results directly evidence the EDL structure, bridging the gap between the theoretical and experimental understandings of the interface.

The role of lactate deshydrogenase levels on non-small cell lung cancer prognosis: a meta-analysis.

The role of serum lactate dehydrogenase (LDH) on the clinical outcomes of non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) tyrosine-kinase inhibitors (TKIs) treatment remained to be elucidated. Therefore, we did this meta-analysis. We searched databases including PubMed, EMBASE, and Cochrane Library till to June, 2017. The relationships between the LDH levels and overall survival (OS) and progression free survival (PFS) were assessed by calculating hazard ratios (HRs) and 95% confidence intervals (CIs). The association between the LDH levels and disease control rate (DCR) was calculated by odds ratio (OR) and 95% CI. Seven studies were included in the meta-analysis. As for DCR, the result from this meta-analysis was not positive (OR=0.71; 95% CI 0.21 - 2.37; P=0.57). As for PFS, the result of the meta-analysis indicated that elevated LDH was significantly associated with shorter PFS (HR=1.88; 95%CI, 1.37-2.59). When studies were stratified by ethnicity, significant association was also observed in Asian group (HR=2.36; 95%CI, 1.57-3.55). As for OS, patients with high levels of LDH showed significantly shorter OS (HR=2.44; 95%CI, 1.84-3.23). In the subgroup by race, significant associations were found in Asian group (HR=2.62; 95%CI, 1.61-4.26) and Caucasian population (HR=2.36; 95%CI, 1.66-3.34). In conclusion, this meta-analysis suggested that elevated LDH level was associated with the poor PFS and OS of NSCLC patients receiving EGFR-TKIs treatment.

[Penile hemodynamics in different erection phases].

OBJECTIVE: To compare the hemodynamic indexes of penile cavernosal arteries in different phases of penile erection and determine the optimal time for color Doppler ultrasonography of the penis. METHODS: Forty healthy adult male volunteers with normal erectile function received intracavernous injection of 10 µg Alprostadil together with visual and auditory stimuli. Within the next 30 minutes, we monitored dynamically the blood flow in the bilateral penile cavernosal arteries, and recorded and compared the peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance index (RI) in the phases of latency, tumescence, full erection and rigid erection. RESULTS: Fourteen of the subjects experienced latency, tumescence and full erection only, but failed to achieve rigid erection. PSV and RI were significantly higher while EDV remarkably lower in the tumescence and full erection phases than in the latency phase (all P < 0.01). Statistically significant differences were observed between the tumescence and full erection phases in EDV and RI (both P < 0.01) but not in PSV (P > 0.05). Among the 26 males that achieved rigid erection, PSV, EDV and RI showed significant differences between the full and rigid erection phases (all P < 0.01), but not between the left and right cavernosal arteries in the same phase (P > 0.05). CONCLUSIONS: The blood flow in the penile cavernosal arteries changes dynamically in the process of penile erection, and the hemodynamic indexes obtained in the full erection phase can better reflect the function of penile cavernous vessels.

[Qilin Pills improve sperm quality in patients with oligozoospermia].

OBJECTIVE: To observe the therapeutic effect of Qilin Pills (QLP) on oligoasthenospermia. METHODS: This prospective study included 168 patients diagnosed with oligozoospermia in our hospital between September 2015 and September 2017, and all of them failed to achieve pregnancy. We randomly divided them into a QLP group (n = 82) and a placebo control group (n = 86) to receive oral QLPs or placebo pills, respectively, both at 6 g tid for 6 months. We followed up the patients and recorded their routine semen parameters every month during the medication and the rate of pregnancy in their spouses. RESULTS: After 6 months of treatment, the QLP group, as compared with the placebo controls, showed significantly improved sperm concentration (25.13 ×106/ml vs 11.62 ×106/ml, P < 0.01), grade a+b sperm (33.81% vs 17.32%, P < 0.01), grade a sperm (22.84% vs 13.56%, P < 0.01) and sperm motility (56.33% vs 26.23%, P < 0.01); and 26 pregnancies were achieved in the QLP group (32.91%), remarkably more than 13 in the placebo control group (15.85%) (P < 0.01). CONCLUSIONS: Qilin Pills can effectively improve sperm quality and increase the rate of pregnancy.

M10, a novel derivative of Myricetin, prevents ulcerative colitis and colorectal tumor through attenuating robust endoplasmic reticulum stress.

Chronic gut inflammation disposes to an increased risk of colitis-associated cancer. Chemoprevention is an attractive complementary strategy. We aimed to evaluate the chemopreventive effects of M10, a novel derivative of Myricetin, in the murine azoxymethane/dextran sodium sulfate model. Oral administration of M10 at 50-100 mg/kg once a day for consecutive 12 weeks significantly prevented ulcerative colitis (UC) and colorectal tumor. Pathological analysis of intestines showed that M10 reduced the degree of chronic inflammation and prevented the progression of colorectal tumorigenesis. Flow cytometry analysis of the immunocytes isolated from intraepithelial and lamina propria showed that M10 prevented the infiltration of myeloid-derived suppressor cells and increased CD8+T and CD4+T cells in colorectal tissues. Enzyme-linked immunosorbent analysis revealed the reduction of pro-inflammatory mediators granulocyte-macrophage colony-stimulating factor/macrophage colony-stimulating factor, IL-6 and TNF-α in colonic mucosa. Western blot assay also showed M10 prevention of the NF-κB/IL-6/STAT3 pathways and the biomarkers of inflammation and colorectal tumorigenesis. Electron microscopy analysis revealed that M10 prevent robust endoplasmic reticulum (ER) stress-induced autophagy in inflamed colonic mucosal cells. In conclusion, oral administration of Myricetin derivative M10 exerts chemoprevention of UC and colorectal tumor in mice. The mechanism of chemoprevention is associated with the reduction of biomarkers of chronic inflammation and proliferation through attenuating robust ER stress in inflamed colonic mucosal cells. M10 exerts chemoprevention activity without evidence of toxicity in mice. These results justify further evaluation of M10 in clinical trials. M10 could develop a promising regimen in the chemoprevention of colitis and colorectal cancer.

17q21 locus rs7216389 polymorphism and childhood asthma risk: a meta-analysis.

INTRODUCTION: Recently, a genome-wide association study (GWAS) indicated that rs7216389 polymorphism on chromosome 17q21 was associated with paediatric asthma risk. However, the results remained controversial. Therefore, a meta-analysis was performed. EVIDENCE ACQUISITION: A comprehensive literature retrieve was performed on PubMed, Embase and Science Direct databases up to Feb 20, 2016. The strength of association between 17q21 locus rs7216389 polymorphism and pediatric asthma risk was assessed by computing odds ratio (OR) with its corresponding 95% confidence interval (CI). EVIDENCE SYNTHESIS: A total of 10 studies with 7797 cases and 38757 controls were included. A statistically significant association of rs7216389 polymorphism and pediatric asthma risk was found (OR=1.41, 95%CI=1.34-1.49, P<0.00001). Furthermore, both Caucasians (OR=1.41, 95%CI=1.33-1.49, P<0.00001) and Asians (OR=1.43, 95%CI=1.25-1.63, P<0.00001) with rs7216389 polymorphism showed significant association, respectively. A significantly increased susceptibility was identified in atopic asthma (OR=1.45, 95%CI=1.22-1.72, P<0.00001). In the stratification analysis by study design, both case-control studies (OR=1.40, 95%CI=1.33-1.48, P<0.00001) and cohort studies (OR=2.05, 95%CI=1.32-3.17, P=0.001) showed significant association, respectively. CONCLUSIONS: In conclusion, this meta-analysis suggests that 17q21 locus rs7216389 polymorphism was significantly associated with paediatric asthma risk.

Optical damage resistant Ti-diffused Zr/Er-codoped lithium niobate strip waveguide for high-power 980 nm pumping.

Ti4+-diffused Zr4+/Er3+-codoped LiNbO3 strip waveguide was fabricated on an X-cut LiNbO3 substrate by thermal diffusion in sequence of Er3+, Zr4+ and Ti4+. Secondary ion mass spectrometry study shows that the Ti4+ ions follow a sum of two error functions in the width direction and a Gauss function in the depth direction of the waveguide. Both Er3+ and Zr4+ profiles follow the desired Gauss function, and entirely cover the Ti4+ profile. Optical study shows that the waveguide is TE or TM single mode at 1.5 µm wavelength, and has a loss of 0.3 (0.5) dB/cm for the TM (TE) mode. In the case of 980 nm pumping, the waveguide shows stable 1547 nm signal output under high-power pumping without optical damage observed, and a net gain of 1.1 dB/cm is obtained for the available pump power of 120 mW.

The prognostic value of pretreatment tumor apparent diffusion coefficient values in nasopharyngeal carcinoma.

BACKGROUND: Diffusion-weighted MR imaging (DWI) has increasingly contributed to the management of nasopharyngeal carcinoma (NPC) patients. The objective of this paper was to explore the prognostic significance of apparent diffusion coefficient (ADC) values in 93 NPC patients. METHODS: This retrospective study included 93 newly diagnosed NPC patients. Pretreatment ADC values were determined and compared with patients' age, gender, alcohol intake, smoking, tumor volume, pathological type, tumor stage, and nodal stage. Using the Kaplan-Meier method, overall survival (OS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) were calculated and the values compared between the low and high ADC groups. Multivariate analysis of ADC values and other 9 clinical parameters was performed using a Cox proportional hazards model to test the independent significance for OS, LRFS and DMFS. RESULTS: The mean ADC value for the initial nasopharyngeal tumors was 0.72 × 10-3 mm2/s (range: 0.48-0.97 × 10-3 mm2/s). There was no significant difference between pretreatment ADCs and patient' gender, age, smoking, alcohol intake, or tumor stage. A significant difference in the ADCs for different N stages (P = 0.022) and correlation with initial tumor volume (r = -0.26, P = 0.012) were observed. In comparison, the ADC value for undifferentiated carcinoma was lower than that for other 3 pathological types. With a median follow-up period of 50 months, the 3-year and 5-year OS rates were 88.2% and 83.3%, respectively, 3-year and 5-year LRFS rates were 93.5% and 93.3%, respectively, and 3-year and 5-year DMFS rates were 83.9% and 83.3%, respectively. Patients with tumor ADC values ≥0.72 × 10-3 mm2/s exhibited longer OS and LRFS periods compared with tumor ADC values <0.72 × 10-3 mm2/s, with P values 0.036 and 0.018, respectively. In addition, patients with deaths or recurrences or distant metastasis had significant lower ADC values than those without disease failures. According to a multivariate analysis using the Cox proportional hazard test, ADC values showed a significant correlation with OS (P = 0.0004), LRFS (P = 0.0009), and DMFS (P < 0.0001), respectively. CONCLUSIONS: Pretreatment tumor ADC values supposed to be a noninvasive important prognostic parameter for NPC.

Noninvasive evaluation of gastric emptying and gastric wall thickness in SLE patients.

OBJECTIVE: The objective of this study is to evaluate the gastric emptying in patients with systemic lupus erythematosus (SLE) with gastrointestinal involvement using three-dimensional (3D) ultrasonography. METHODS: The gastric emptying times at 25% (T1), 50% (T2), and 75% (T3) of SLE patients with gastrointestinal involvement (n = 40) and healthy controls (n = 80) were evaluated and compared. In addition, the correlations among the gastric wall thickness, SLE disease activity index (SLEDAI), and upper gastrointestinal symptoms were calculated. RESULTS: The gastric wall thickness was correlated with the SLEDAI (r = 0.928, p < 0.001) and the upper gastrointestinal symptom index (r = 0.848, p < 0.001). The emptying times T1, T2, and T3 of the SLE patients were 17.08 ± 2.65 min (mean ± standard deviation), 39.85 ± 6.54 min, and 83.58 ± 7.12 min, respectively. For healthy controls, they were 19.65 ± 5.39 min, 41.08 ± 7.51 min, and 70.34 ± 8.03 min. The T1 of the SLE patients was shorter (p < 0.01), while the T3 was longer (p < 0.001). Moreover, T3 in the SLE group had the best correlation with the upper gastrointestinal symptom index (r = 0.553, p < 0.001). T1 in the SLE group was anti-correlated with early satiety (r = -0.366, p < 0.05). CONCLUSIONS: Combining the emptying times T1 and T3, as well as the gastric wall thickness, the SLEDAI and the upper gastrointestinal symptoms index can provide accurate clinical diagnosis of SLE with gastric involvement.

Correction: Shell-isolated nanoparticle-enhanced Raman spectroscopy study of the adsorption behaviour of DNA bases on Au(111) electrode surfaces.

Correction for 'Shell-isolated nanoparticle-enhanced Raman spectroscopy study of the adsorption behaviour of DNA bases on Au(111) electrode surfaces' by Bao-Ying Wen et al., Analyst, 2016, DOI: 10.1039/c6an00180g.

Shell-isolated nanoparticle-enhanced Raman spectroscopy study of the adsorption behaviour of DNA bases on Au(111) electrode surfaces.

For the first time, we used the electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy (EC-SHINERS) technique to in situ characterize the adsorption behaviour of four DNA bases (adenine, guanine, thymine, and cytosine) on atomically flat Au(111) electrode surfaces. The spectroscopic results of the various molecules reveal similar features, such as the adsorption-induced reconstruction of the Au(111) surface and the drastic Raman intensity reduction of the ring breathing modes after the lifting reconstruction. As a preliminary study of the photo-induced charge transfer (PICT) mechanism, the in situ spectroscopic results obtained on single crystal surfaces are excellently illustrated with electrochemical data.

Interaction effects on cytochrome P450 both in vitro and in vivo studies by two major bioactive xanthones from Halenia elliptica D. Don.

The major components, 1-hydroxy-2,3,5-trimethoxy-xanthone (HM-1) and 1,5-dihydroxy-2,3-dimethoxy-xanthone (HM-5) isolated from Halenia elliptica D. Don (Gentianaceae), could cause vasodilatation in rat coronary artery with different mechanisms. In this work, high-performance liquid chromatography coupled to ion trap time-of-flight mass spectrometry (LCMS-IT-TOF) was used to clarify the metabolic pathways, and CYP450 isoform involvement of HM-1 and HM-5 were also studied in rat. At the same time, in vivo inhibition effects of HM-1 and ethyl acetate extracts from origin herb were studied. Three metabolites of HM-5 were found in rat liver microsomes (RLMs); demethylation and hydroxylation were the major phase I metabolic reactions for HM-5. Multiple CYP450s were involved in metabolism of HM-1 and HM-5. The inhibition study showed that HM-5 inhibited Cyp1a2, 2c6 and 2d2 in RLMs. HM-1 inhibited activities of Cyp1a2, Cyp2c6 and Cyp3a2. In vivo experiment demonstrated that both HM-1 and ethyl acetate extracts could inhibit Cyp3a2 in rats. In conclusion, the metabolism of xanthones from the origin herb involved multiple CYP450 isoforms; in vitro, metabolism of HM-5 was similar to that of its parent drug HM-1, but their inhibition effects upon CYP450s were different; in vivo, Cyp3a2 could be inhibited by HM-1 and ethyl acetate extracts.

[Study on Simultaneous Mercury and Lead Detection in Water Samples with PGNAA-XRF].

Prompt gamma neutron activation analysis (PGNAA) technology is used in heavy metals measurement. It is found that the detection accuracy of lead (Pb) is impacted heavily by mercury (Hg), because of thermal neutron cross section of mercury is much bigger than lead. In this paper, a new combined detection method was proposed to improve the lead measurement accuracy in situ environmental water rejects analysis by PGNAA-XRF. Thus, a combined measurement facility was developed to analyze the mercury and lead in water simultaneously. The geometry of set-up is determined by a series of simulations with the MCNP code to improve the detection efficiency of the prompt gamma-ray intensity (Iγ) and characteristic X-ray fluorescence intensity (IX) of element. The ideal sample height and cavity are 33 and 16 cm, respectively. The influence of the relationship between Iγ, IX and different concentration (ｃi) of Hg and Pb was researched by MCNP calculations, respectively. The simulation results showed that there were good linear relationships between Iγ, IX and ｃi, respectively. The empirical formula of combined detection method was proposed based on the above calculations. The limits of detection for Hg and Pb with the combined measurement instrument were 3.89 and 4.80 mg·kg-1, respectively. It is a significant increase in performance of the mercury and lead detection simultaneously.

Effect of Berberine on promoting the excretion of cholesterol in high-fat diet-induced hyperlipidemic hamsters.

BACKGROUND: Berberine (BBR), as a new medicine for hyperlipidemia, can reduce the blood lipids in patients. Mechanistic studies have shown that BBR activates the extracellular-signal regulated kinase pathway by stabilizing low-density-lipoprotein receptor mRNA. However, aside from inhibiting the intestinal absorption of cholesterol, the effects of BBR on other metabolic pathways of cholesterol have not been reported. This study aimed to investigate the action of BBR on the excretion of cholesterol in high-fat diet-induced hyperlipidemic hamsters. METHODS: Golden hamsters were fed a high-fat diet (HFD) for 6 weeks to induce hyperlipidemia, followed by oral treatment with 50 and 100 mg/kg/day of BBR or 10 and 30 mg/kg/day of lovastatin for 10 days, respectively. The levels of total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), transaminases, and total bile acid in the serum, liver, bile and feces were measured using an enzyme-linked immunosorbent assay. The cholesterol (as well as coprostanol) levels in the liver, bile and feces were determined by gas chromatography-mass spectrometry. RESULTS: The HFD hamsters showed significantly hyperlipidemic characteristics compared with the normal hamsters. Treatment with BBR for 10 days reduced the serum TC, TG and LDL-C levels in HFD hamsters by 44-70, 34-51 and 47-71%, respectively, and this effect was both dose- and time-dependent. Initially, a large amount of cholesterol accumulated in the hyperlipidemic hamster livers. After BBR treatment, reductions in the liver cholesterol were observed by day 3 and became significant by day 7 at both doses (P < 0.001). Meanwhile, bile cholesterol was elevated by day 3 and significantly increased at day 10 (P < 0.001). BBR promoted cholesterol excretion from the liver into the bile in hyperlipidemic hamsters but not in normal hamsters, and these results provide a link between the cholesterol-lowering effect of BBR with cholesterol excretion into the bile. CONCLUSIONS: We conclude that BBR significantly promoted the excretion of cholesterol from the liver to the bile in hyperlipidemic hamsters, which led to large decreases in the serum TC, TG and LDL-C levels. Additionally, compared with lovastatin, the BBR treatment produced no obvious side effects on the liver function.