Pharmacokinetic, metabolic profiling and elimination of brusatol in rats

Brusatol, a quassinoid isolated from the traditional Chinese medicine Brucea javanica, has been reported to be an inhibitor of Nrf2 pathway and has great potential to be developed into a novel chemotherapeutic adjuvant. However, the in vivo process of brusatol has not been comprehensively explained yet. Therefore, this paper focused on the pharmacokinetic metabolism and excretion of brusatol in rats using a simple and reproducible LC-MS/MS method. The results indicated that the plasma concentration of brusatol decreased rapidly; the average cumulative excretion rate in urine was 5.82% during 24 h, and 0.71% in bile during 12 h. High-resolution mass spectrometry was applied for the identification of metabolites; as a result, four metabolites were detected and the structure was tentatively deduced on the base of the MS² data, Compound Discoverer 2.0 and Mass Frontier 7.0 software. Hydroxylation, hydrolysis and glucuronidation were suggested as major metabolic pathways in vivo. The in vivo process and detection of metabolites of brusatol might improve the understanding of the mechanism of its anticancer effect and provide valuable information for its safety estimation, which will be essential to the new drug development.

A cardioid oscillator with asymmetric time ratio for establishing CPG models

Nonlinear oscillators are usually utilized by bionic scientists for establishing central pattern generator models for imitating rhythmic motions by bionic scientists. In the natural word, many rhythmic motions possess asymmetric time ratios, which means that the forward and the backward motions of an oscillating process sustain different times within one period. In order to model rhythmic motions with asymmetric time ratios, nonlinear oscillators with asymmetric forward and backward trajectories within one period should be studied. In this paper, based on the property of the invariant set, a method to design the closed curve in the phase plane of a dynamic system as its limit cycle is proposed. Utilizing the proposed method and considering that a cardioid curve is a kind of asymmetrical closed curves, a cardioid oscillator with asymmetric time ratios is proposed and realized. Through making the derivation of the closed curve in the phase plane of a dynamic system equal to zero, the closed curve is designed as its limit cycle. Utilizing the proposed limit cycle design method and according to the global invariant set theory, a cardioid oscillator applying a cardioid curve as its limit cycle is achieved. On these bases, the numerical simulations are conducted for analyzing the behaviors of the cardioid oscillator. The example utilizing the established cardioid oscillator to simulate rhythmic motions of the hip joint of a human body in the sagittal plane is presented. The results of the numerical simulations indicate that, whatever the initial condition is and without any outside input, the proposed cardioid oscillator possesses the following properties: (1) The proposed cardioid oscillator is able to generate a series of periodic and anti-interference self-exciting trajectories, (2) the generated trajectories possess an asymmetric time ratio, and (3) the time ratio can be regulated by adjusting the oscillator's parameters. Furthermore, the comparison between the simulated trajectories by the established cardioid oscillator and the measured angle trajectories of the hip angle of a human body show that the proposed cardioid oscillator is fit for imitating the rhythmic motions of the hip of a human body with asymmetric time ratios.

ERAP1/ERAP2 and RUNX3 polymorphisms are not associated with ankylosing spondylitis susceptibility in Chinese Han

Previous studies show that endoplasmic reticulum‐associated aminopeptidase (ERAP1/ERAP2) and runt‐related transcription factor 3 (RUNX3) gene polymorphisms are associated with AS (ankylosing spondylitis) in European Caucasians. However, contradictory results were reported in different Asian populations. The purpose of this study was to determine whether eleven candidate single nucleotide polymorphisms (SNPs) in ERAP1/ERAP2 and six in RUNX3 genes confer susceptibility to AS with or without acute anterior uveitis (AAU) [AS⁺AAU⁺ or AS⁺AAU^–] in Chinese Han. Therefore, a case–control association study was performed in 882 AS⁺AAU^–, 884 AS⁺AAU⁺ and 1727 healthy controls. Genotyping was performed using the iPLEXGold genotyping assay. A meta‐analysis was performed to assess the association of polymorphisms of ERAP1 with AS susceptibility in Asian populations. No association was found between SNPs of ERAP1/ERAP2/RUNX3 and susceptibility of AS with or without AAU. A case–control study between patients with human leucocyte antigen HLA‐B27‐positive and healthy controls also failed to demonstrate an association of the tested SNP with AS with or without AAU. Moreover, a meta‐analysis showed that there was no association of rs30187, rs27037, rs27980, rs27434 and rs27582 in ERAP1 with AS in Chinese Han. Taken together, 17 SNPs in ERAP1/ERAP2 and RUNX3 genes did not confer disease susceptibility to AS in Chinese Han.

Comparison of New Liquid Chromatography-Mass Spectrometry Method and Enzyme-Multiplied Immunoassay Technique for Routine Therapeutic Drug Monitoring of Vancomycin in Chinese Patients

BACKGROUND

Therapeutic drug monitoring of vancomycin is very valuable due to the good correlation between trough levels and clinical outcome. Therefore, it is important to accurately determine the concentration of vancomycin in patient plasma for adequate dose-adjustment. The objective of this study was to develop a new liquid chromatography-mass spectrometry (LC-MS) method for determination of vancomycin in patient plasma and compare the results with those obtained from enzyme-multiplied immunoassay technique (EMIT).

METHODS

After extraction by simple protein precipitation, vancomycin and bergenin (internal standard) were separated on a C18 column (150×4.6 mm, 5 µm) at 40°C by gradient elution with 0.1% formic acid and acetonitrile as the mobile phase and measured by electrospray ionization source in positive selective ion monitoring mode. Seventy-nine plasma samples from patients with severe infection were analyzed by enzyme-multiplied immunoassay technique and LC-MS method. MedCalc 15.2 software with Bland-Altman analysis and Passing-Bablok regression analysis was used for statistical analysis.

RESULTS

The weighted (1/x2) calibration curve of the validated LC-MS was linear within the concentration range of 0.25 - 40 µg/mL. The inter- and intra-day precisions (%RSD) were less than 10.0%. No significant matrix effect was observed in the relevant time ranges. Comparison of the two methods indicated that results of the LC-MS were close to that of EMIT with a correlation coefficient of 0.957. Upon Bland-Altman analysis, the bias amounted to 2.9 µg/mL (95% confidence intervals of -3.4 - 9.2 µg/mL).

CONCLUSIONS

The established LC-MS method and EMIT were both suitable for routine TDM of vancomycin.

Insulin-like growth factor I reduces the occurrence of necrotizing enterocolitis by reducing inflammatory response and protecting intestinal mucosal barrier in neonatal rats model

OBJECTIVE

To observe the effect of enteral supplement of insulin-like growth factor I (IGF-1) on dynamic changes of TLR4, NF-κB, IL-6, SIgA and MUC2 in intestinal tissues of neonatal rats, and to investigate the protective effects and possible mechanisms of IGF-1 on necrotizing enterocolitis (NEC).

MATERIALS AND METHODS

Specific pathogen free (SPF) neonatal Sprague Dawley (SD) rats aged 3 days old were randomly divided into 3 groups, namely, normal control group, NEC model group and IGF-1 intervention group. In NEC group, the neonatal NEC rat models were established using artificial feeding, hypoxia and cold stimulation. In IGF-1 intervention group, the models were established by means of artificial feeding plus hypoxia and cold stimulation, and IGF-1 (22 ug/L) at a physiological concentration similar to the breast milk was added to milk replacer for intervention. The rats in the three groups were killed after the blood was collected from the heart at 24, 48 and 72 h, respectively, following the establishment of models; then, 3 cm of the terminal ilea were dissected and used for histopathological examination, RT-PCR and ELISA studies after hematoxylin and eosin (HE) staining.

RESULTS

Symptoms in IGF-1 intervention group were significantly relieved, and the incidence rate of NEC was lowered remarkably. In NEC model group, the peak expression of TLR4 mRNA occurred later than that of NF-κB mRNA and IL-6, and the expressions of TLR4 mRNA, NF-κB mRNA and IL-6 were decreased at 72 h after IGF-1 intervention. In NEC model group, the expression of MUC2 showed a transient decrease, the expression of SIgA was on the decline, but the expressions of MUC2 and SIgA were increased after IGF-1 intervention.

CONCLUSIONS

The enteral administration of IGF-1 at a physiological concentration can ameliorate the clinical symptoms in neonatal NEC rat models and decrease the occurrence rate. The possible mechanism is that IGF-1 down-regulates the TLR4 mRNA expression to inhibit the production of inflammatory mediators, and it up-regulates the expressions of MUC2 and SIgA to protect the mechanical and immuno-barrier functions of the intestinal mucous.

Comparison of the docetaxel concentration in human plasma measured with liquid chromatography-tandem mass spectrometry (LC-MS/MS) and a nanoparticle immunoassay and clinical applications of that assay

To determine the feasibility of using a nanoparticle immunoassay for clinical therapeutic drug monitoring (TDM) of docetaxel concentrations, a sensitive and simple method of liquid chromatography-tandem mass spectrometry (LC-MS/MS) was established to measure the docetaxel concentration in human plasma and the results of LC-MS/MS and the immunoassay were compared. Docetaxel and paclitaxel (the internal standard, or IS) in human plasma were extracted through protein precipitation, separated on a Diamonsil C18 column (150 mm × 4.6 mm, 5 μm), ionized with positive ions, and detected with LC-MS/MS in multi-reaction monitoring (MRM) mode. Plasma samples from 248 cancer patients were assayed with LC-MS/MS and a nanoparticle immunoassay. Data from the samples were analyzed with the statistical software SPSS and the software MedCalc. Results indicated that the calibration curve of the validated method of LC-MS/MS was linear over the range of 10-2,000 ng/mL, with an lowest limit of quantitation (LLOQ) of 10 ng/mL, and the intra- and inter- day precision and accuracy were both < ± 15%. Comparison of the two methods indicated that results of the LC-MS/MS were closely related to those of the nanoparticle immunoassay, with a correlation coefficient (R) of 0.965 and acceptable 95% confidence intervals (CI) of ‒ 231.7-331.1 ng/mL. Overall, the established method of LC-MC/MS and the nanoparticle immunoassay were both suitable for measurement of the docetaxel concentration in human plasma, and the immunoassay was far more cost-effective and better at clinical TDM of docetaxel in clinical practice.

Influences of RFA combined with TACE on the HIF-1α and EGR level of patients with primary hepatic carcinoma

OBJECTIVE

To discuss the influences of radiofrequency ablation (RFA) combined with hepatic arterial chemoembolization on the expression level of immunity and hypoxia-inducible factor (HIF-1a) and early growth response protein2 (EGR2) of patients with hepatocarcinoma.

PATIENTS AND METHODS

Patients with primary hepatic carcinoma treated in our hospital from 2011 to 2014 were divided into research group (RFA+TACE) and control group (TACE) according to different therapy methods, with 72 patients in each group. Then, the immunity functions were detected before treatment and 3 months after treatment, the expression level of HIF-1a, EGR-2, the alpha fetal protein (AFP), the therapeutic effect, and incidence of adverse reaction in near and specific future were compared between two groups.

RESULTS

After treatment, the ratio of CD3+ and CD4+T cells, specific vale of CD4/CD8, and NK cell population in research group were more than those in control group, while the ratio of CD8+T cells was less than that in control group with statistical significance. Meanwhile, the expression levels of HIF-1a (F between-group*time point = 5.353, p = 0.043), EGR-2 (F between-group*time point = 4.385, p = 0.044), and AFP (F between-group*time point = 4.205, p = 0.045) had difference with statistical significance. Moreover, the recent therapy response rate in research group was 76.4%, which was higher than that in control group (50.0%), with significant difference (χ2 = 10.784, p = 0.029), while the difference of long-term therapeutic effect between two groups has statistical significance (χ2 = 7.439, p = 0.005).

CONCLUSIONS

The treatment of primary hepatic carcinoma by TACE combined with RAF therapeutic schedule was helpful in improving organic immunity, decreasing tumor angiogenesis and reducing tumor cell proliferation speed to improve the short- and long-term therapeutic effects.

Sex differences in the impact of nonalcoholic fatty liver disease on cardiovascular risk factors

BACKGROUND AND AIMS

Information on sex differences in the association of nonalcoholic fatty liver disease (NAFLD) with cardiovascular disease (CVD) risk factors is scarce. We examined whether men exhibit greater differences in established CVD risk factors between NAFLD and non-NAFLD than women.

METHODS AND RESULTS

We conducted a cross-sectional analysis using a cohort of 10761 apparently healthy Chinese adults who underwent comprehensive health checkups including abdominal ultrasonography. In the setting of NAFLD and non-NAFLD, although men had significantly higher levels of atherogenic lipids as indicated by higher levels of triglyceride, triglyceride/HDL-cholesterol, and lower levels of HDL-cholesterol and worsen renal function as indicated by higher levels of creatinine and lower levels of estimated glomerular filtration rate (eGFR) than female counterparts, men with NAFLD showed greater relative differences in atherogenic lipids and deteriorated renal function than women with NAFLD when compared with their non-NAFLD counterparts. The interactions between sex and NAFLD on triglyceride, HDL-cholesterol, triglyceride/HDL-cholesterol, creatinine, and eGFR were statistically significant (P < 0.05). In the multivariate Logistic regression analyses, we observed a stronger association of TG with NAFLD and comparable associations of eGFR or HDL-C with NAFLD in men compared with women.

CONCLUSION

There was greater adverse influence of NAFLD per se on triglyceride, and triglyceride/HDL-cholesterol in men compared with women. The greater adverse influence of NAFLD per se on HDL-C and eGFR in men compared with women probably related to the gender differences in TG levels.

Ten-year follow-up analysis of chronic hepatitis C patients after getting sustained virological response to pegylated interferon-α and ribavirin therapy

There is little data on the long-term follow-up outcomes of chronic hepatitis C patients achieving sustained virological response (SVR) after treatment with peglylated interferon-α plus ribavirin. We prospectively investigated the overall clinical, biochemical, virological and histological outcomes in a ten-year cohort study of 325 patients with chronic hepatitis C achieving SVR to pegylated interferon-α and ribavirin therapy. Patients underwent consistent clinical, biochemical and virological evaluation every six months, and patients with pretherapy Ishak fibrosis score ≥2 were invited to accept a second liver biopsy at the last follow-up. Liver biopsy specimens were evaluated using Ishak's scoring system. At the end of follow-up, five patients developed decompensated liver cirrhosis. One patient (0.3%) with pretherapy cirrhosis was diagnosed with hepatocellular carcinoma (HCC). A total of 305 patients (94%) had normal serum ALT and AST levels during the entire period of follow-up. Twenty-seven patients (8%) had conclusive evidence of virological relapse. Among the 117 patients with paired pretherapy and long-term follow-up biopsies, 96 (82%) had a decreased fibrosis score. Ninety-nine (79%) had a decrease in combined inflammation score. Thirty-seven (32%) had normal or nearly normal livers on long-term follow-up biopsy. SVR achieved with PEG-IFN-α and RBV combination therapy is durable, while late virological relapse may still occur in some patients. Clinical outcomes for patients who obtain SVR are excellent, although the patients with cirrhosis are still at a low risk of hepatocellular carcinoma.

Simple, rapid and highly sensitive HPLC method for measurement of Lamotrigine in human plasma and its clinical applications

Spikes in Lamotrigine concentrations levels and associated clinical toxicity may occur unpredictably. This study describes the development and validation of a simple, more rapid, highly sensitive and economical method for measuring Lamotrigine (LTG) concentration levels in human plasma using HPLC-UV and its clinical applications. Analyte from plasma was extracted with methanol (protein precipitation) and separated on the analytical column Diamonsil C₁₈ (150mm×4.6mm, 5μm) Waters-Milford, MA, United States. Mixture of 0.1% Trifluoroacetate and Methanol used as mobile phase in a 59:41 volume/volume mixture with an isocratic flow rate of 1.5 ml/min and wavelength was adjusted to 260nm. Standard curve of lamotrigine showed good linearity over the range of 1.0-50μg/mL (r²=0.9961) and LLOQ was 1.0μg/ml. The Specificity, Recovery, Accuracy, Stability, Robustness and RSDs for both intraday and interday precision were within acceptable limits. The highly sensitive HPLC assay for determination of LTG in human plasma was demonstrated, validated and applied in Therapeutic Drug Monitoring (TDM) of sixty seven epilepsy patients who were using LTG. The proposed method can be easily applied in routine Therapeutic monitoring of LTG, Besides TDM, stated method can be also very useful for Bioequivalence studies, Pharmacovigilance and Pharmacokinetics studies.

Measuring perceived rehabilitation needs of people with schizophrenia in mainland China

This paper reports the development and validation of the Wuxi version of the Rehabilitation Needs Questionnaire for People with Schizophrenia (PRNQ-S-WX) based on the original Hong Kong version. PRNQ-S-WX was validated by exploratory factor analysis (EFA) using a convenience sample of 250 people with schizophrenia. EFA yielded a 17-factor solution accounting for 81.3 % of the total variance which resulted in a 75-item PRNQ-S-WX. The questionnaire has sound internal consistencies. Its factor structure is similar to the Hong Kong version. Some suggestions for policy, service and research development in mental health in mainland China are made.

Mechanoresponsive Properties of the Periodontal Ligament

The periodontal ligament (PDL) functions as an enthesis, a connective tissue attachment that dissipates strains created by mechanical loading. Entheses are mechanoresponsive structures that rapidly adapt to changes in their mechanical loading; here we asked which features of the PDL are sensitive to such in vivo loading. We evaluated the PDL in 4 physiologically relevant mechanical environments, focusing on mitotic activity, cell density, collagen content, osteogenic protein expression, and organization of the tissue. In addition to examining PDLs that supported teeth under masticatory loading and eruptive forces, 2 additional mechanical conditions were created and analyzed: hypoloading and experimental tooth movement. Collectively, these data revealed that the adult PDL is a remarkably quiescent tissue and that only when it is subjected to increased loads—such as those associated with mastication, eruption, and orthodontic tooth movement—does the tissue increase its rate of cell proliferation and collagen production. These data have relevance in clinical scenarios where PDL acclimatization can be exploited to optimize tooth movement.

A survey of outcomes and management of patients post fragility fractures in China

We found that the fragility hip and vertebral fractures caused excess mortality rates in this Chinese female population, which was unexpectedly lower than those in western countries and other Asian countries. This was the first nationwide survey relating to post-fracture outcomes conducted among Chinese population in Mainland China.

INTRODUCTION

This study aimed to investigate the mortality, self-care ability, diagnosis, and medication treatment of osteoporosis following fragility hip and vertebral fractures through a nationwide survey among female patients aged over 50 in Mainland China.

METHODS

This was a multicenter, retrospective cohort study based on medical chart review and patient questionnaire. Female patients aged 50 or older admitted for low-trauma hip or vertebral fractures and discharged from Jan 1, 2008 to Dec 31, 2012 were followed.

RESULTS

Total of 1151 subjects of hip fracture and 842 subjects of vertebral fracture were included. The mean age was 73.4 ± 10.0, and the median of duration from index fracture to interview was 2.6 years. The overall 1-year, 2-year, 3-year, 4-year, and 5-year cumulative mortality rates were 3.5, 7.0, 11.2, 13.1, and 16.9 %, respectively. The first year mortality rates in hip (3.8 %, 95% CI 3.3-4.4 %) and vertebral fracture (3.1 %, 95% CI 2.5-3.7 %) were significantly higher than that in the general population (1.6 %). Impaired self-care ability was observed in 33.2, 40.6, and 23.8 % of overall, hip fracture, and vertebral fracture group, respectively. The overall diagnosis rate of osteoporosis was 56.8 %, and bone mineral density (BMD) measurement had never been conducted in 42.0 % among these women. After the index fracture, 69.6 % of them received supplements and/or anti-osteoporotic medications, among which 39.6 % only received calcium with/without vitamin D supplementation.

CONCLUSIONS

The osteoporotic hip and vertebral fractures caused excess mortality rates in this population of Mainland China. The current diagnosis and medical treatment following the fragility fractures is still insufficient in Mainland China.

Towards next generation adenosine A(2A) receptor antagonists

The Adenosine A2A receptor is a member of the G-protein coupled receptor superfamily. It plays a key role in numerous physiological processes through the central nervous system and in peripheral tissues. Functional interactions between the A2A and dopamine D2 receptor has spurred interest in the use of antagonists as anti-Parkinson drugs. Additionally, oncology drugs are now being designed based on the potential for A2A antagonists to function as immunotherapeutics. From early studies based on classical xanthine type A2A antagonists through second generation agents, this mini review will cover aspects of the discovery, development, chemical synthesis and medicinal evaluation of this important class of drugs.

Search for patterns by combining cosmic-ray energy and arrival directions at the Pierre Auger Observatory

Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with [Formula: see text] eV by analyzing cosmic rays with energies above [Formula: see text] eV arriving within an angular separation of approximately 15[Formula: see text]. We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with astrophysical scenarios can therefore be used to obtain constraints on related model parameters such as strength of cosmic-ray deflection and density of point sources.

Isomer-specific comparisons of the hydrolysis of synthetic pyrethroids and their fluorogenic analogues by esterases from the cotton bollworm Helicoverpa armigera

The low aqueous solubility and chiral complexity of synthetic pyrethroids, together with large differences between isomers in their insecticidal potency, have hindered the development of meaningful assays of their metabolism and metabolic resistance to them. To overcome these problems, Shan and Hammock (2001) [7] therefore developed fluorogenic and more water-soluble analogues of all the individual isomers of the commonly used Type 2 pyrethroids, cypermethrin and fenvalerate. The analogues have now been used in several studies of esterase-based metabolism and metabolic resistance. Here we test the validity of these analogues by quantitatively comparing their hydrolysis by a battery of 22 heterologously expressed insect esterases with the hydrolysis of the corresponding pyrethroid isomers by these esterases in an HPLC assay recently developed by Teese et al. (2013) [14]. We find a strong, albeit not complete, correlation (r = 0.7) between rates for the two sets of substrates. The three most potent isomers tested were all relatively slowly degraded in both sets of data but three esterases previously associated with pyrethroid resistance in Helicoverpa armigera did not show higher activities for these isomers than did allelic enzymes derived from susceptible H. armigera. Given their amenability to continuous assays at low substrate concentrations in microplate format, and ready detection of product, we endorse the ongoing utility of the analogues in many metabolic studies of pyrethroids.