Nontraditional risk factors for cardiovascular disease and visceral adiposity index among different body size phenotypes

BACKGROUND AND AIMS

Increased cardiovascular disease and mortality risk in metabolically healthy obese (MHO) individuals remain highly controversial. Several studies suggested risk while others do not. The traditional cardiovascular risk factors may be insufficient to demonstrate the complete range of metabolic abnormalities in MHO individuals. Hence, we aimed to compare the prevalence of elevated lipoprotein (a), apolipoprotein B, and uric acid (UA) levels, apolipoprotein B/apolipoprotein A1 ratio, and visceral adiposity index (VAI) scores, and low apolipoprotein A1 levels among 6 body size phenotypes (normal weight with and without metabolic abnormalities, overweight with and without metabolic abnormalities, and obese with or without metabolic abnormalities).

METHODS AND RESULTS

We conducted a cross-sectional analysis of 7765 Chinese adults using data from the nationwide China Health and Nutrition Survey 2009. MHO persons had intermediate prevalence of elevated apolipoprotein B and UA levels, apolipoprotein B/apolipoprotein A1 ratio and VAI scores, and low apolipoprotein A1 levels between metabolically healthy normal-weight (MHNW) and metabolically abnormal obese individuals (P < 0.001 for all comparisons). Elevated apolipoprotein B and UA concentrations, apolipoprotein B/apolipoprotein A1 ratio, and VAI scores were all strongly associated with the MHO phenotype (all P < 0.01).

CONCLUSIONS

Prevalence of elevated apolipoprotein B and UA levels, apolipoprotein B/apolipoprotein A1 ratio and VAI scores, and low levels of apolipoprotein A1 was higher among MHO persons than among MHNW individuals. The elevated levels of the nontraditional risk factors and VAI scores in MHO persons could contribute to the increased cardiovascular disease risk observed in long-term studies.

High efficiency chlorine removal from polyvinyl chloride (PVC) pyrolysis with a gas-liquid fluidized bed reactor

In this research a gas-liquid fluidized bed reactor was developed for removing chlorine (Cl) from polyvinyl chloride (PVC) to favor its pyrolysis treatment. In order to efficiently remove Cl within a limited time before extensive generation of hydrocarbon products, the gas-liquid fluidized bed reactor was running at 280-320 °C, where hot N2 was used as fluidizing gas to fluidize the molten polymer, letting the molten polymer contact well with N2 to release Cl in form of HCl. Experimental results showed that dechlorination efficiency is mainly temperature dependent and 300 °C is a proper reaction temperature for efficient dechlorination within a limited time duration and for prevention of extensive pyrolysis; under this temperature 99.5% of Cl removal efficiency can be obtained within reaction time around 1 min after melting is completed as the flow rate of N2 gas was set around 0.47-0.85 Nm(3) kg(-1) for the molten PVC. Larger N2 flow rate and additives in PVC would enhance HCl release but did not change the final dechlorination efficiency; and excessive N2 flow rate should be avoided for prevention of polymer entrainment. HCl is emitted from PVC granules or scraps at the mean time they started to melt and the melting stage should be taken into consideration when design the gas-liquid fluidized bed reactor for dechlorination.

Synergistic sporicidal effect of ethanol on a combination of orthophthalaldehyde and didecyldimethylammonium chloride

The objective of this study was to evaluate the potential synergistic effect of ethanol on a combination of orthophthalaldehyde (OPA) and didecyldimethylammonium chloride (DDAC) against the spores of Bacillus subtilis var. Niger. The quantitative carrier test for sporicidal testing of high-level disinfectants according to the guideline of China (Technical Standard for Disinfection 2002) was used as method. Considerable synergistic effect was observed after a 30-min treatment at 20°C. There was an augment in mean log reduction as the concentration of DDAC was increased ranging from 0·2 to 3 g l(-1) in combination with 6 g l(-1) OPA. Ten and 20% ethanol in combination with 6 g l(-1) OPA and 2 g l(-1) DDAC caused more than a 3-log reduction while either 6 g l(-1) OPA, 2 g l(-1) DDAC and 20% ethanol alone or a combination of two of the three agents produced less than a 1-log reduction. Further, 40-min exposure time of combination of OPA, DDAC and 20% ethanol led to greater than a 5-log reduction in spores, and no spore growth was observed following 60- and 90-min exposures.

SIGNIFICANCE AND IMPACT OF THE STUDY

Orthophthalaldehyde (OPA) is very effective at concentrations far lower than its recommended in-use concentration of 0·5% (w/v) and is equally effective against both the gram-negative and gram-positive bacteria. However, it shows lower activity against spores. The synergistic sporicidal effect exhibited by ethanol on a combination of OPA and DDAC can be considered to enhance sporicidal activity for using in situations of sterilization, to reduce in-use concentration of OPA used alone, which may minimize its side effect. OPA may be a more satisfactory and the first-choice agent to replace glutaraldehyde (GTA) as a high-level disinfectant for medical devices.

A simple and sensitive gas chromatography method for determination of isosorbide dinitrate and its metabolites in human plasma: application to pharmacokinetics study on oral spray

A sensitive method for the simultaneous determination of isosorbide dinitrate (ISDN) and its mononitrate metabolites, isosorbide 2-mononitrate and isosorbide 5-mononitrate (IS-2-MN and IS-5-MN), in human plasma was developed using capillary gas chromatography with electron-capture detection, whereas 1,2,4-butanetriol trinitrate was used as internal standard. The analytes were extracted with a simple liquid-liquid extraction from plasma and separated on a DB-1 column. The results of method validation demonstrated that the calibration curves were linear in range of 2-60 ng/mL for ISDN and IS-5-MN, 1-20 ng/mL for IS-2-MN, respectively. The precision (RSD%) was less than 15%, and the lower limit of quantitation was identifiable and reproducible at 2 ng/mL for ISDN and IS-5-MN, 1 ng/mL for IS-2-MN. The analytes in plasma were stable after being stored for more than 30 days and after 2 freeze-thaw cycles (-20 to 25°C). And then this method was successfully applied to a pharmacokinetic investigation on isosorbide dinitrate oral spray in healthy volunteers.

Pharmacokinetic and bioequivalence studies of ibuprofen suspension after a single-dose administration in healthy Chinese volunteers

OBJECTIVE

The aim of this study was to assessed the pharmacokinetic and bioequivalence of 2 formulations of ibuprofen suspension.

METHOD

20 healthy volunteers were enrolled into this random, single-dose, 2-way crossover, open-label, single-centre, pharmacokinetic study. After overnight fasting, 2 formulations (test and reference) of ibuprofen (400 mg ibuprofen/20 mL suspension) were administered as a single dose on 2 treatment days separated by a 7-day washout period. After dosing, blood samples were drawn for a period of 12 h. The plasma samples were analyzed for the presence of ibuprofen by HPLC with ultraviolet detection. Pharmacokinetic parameters were determined from plasma concentrations for both formulations.

RESULTS

The main pharmacokinetics parameters of test and reference were as follows: t1/2 was (1.94±0.38) h and (1.95±0.28) h; Cmax was (33.41±7.83) μg · mL- 1 and (31.08±9.30) μg · mL- 1; AUC0-12 was (91.44±19.26) μg · mL-1 · h and (84.75±24.45) μg · mL-1 · h; AUC0-∞ was (92.82±19.94) μg · mL-1 · h and (85.97±24.99) μg · mL-1 · h; median Tmax was 0.5 h (range, 0.25, 2) and 0.5 h (range, 0.25, 1.5). The 90% confidence intervals of the test/reference treatment ratios for Cmax, AUC0-12 and AUC0-∞ were observed to be within the predetermined acceptable interval of 80-125%.

CONCLUSION

This single-dose study in healthy Chinese fasted volunteers was shown that the ibuprofen test and reference met the requirement of the State Food and Drug Administration, and the test and reference were bioequivalent.

A more rapid, sensitive, and specific HPLC-MS/MS method for nifedipine analysis in human plasma and application to a pharmacokinetic study

A more rapid, sensitive and specific high-performance liquid chromatography coupled to -tandem mass spectrometry (HPLC-MS/MS) was developed and validated for the quantification of nifedipine in human plasma, and applied to the pharmacokinetic study of nifedipine in Chinese healthy volunteers. Nifedipine and internal standard (IS) acetaminophen in plasma were extracted with ethyl acetate, separated on a C18 (150 mm×4.6 mm, 5 µm) reversed-phase column, eluted with acetonitrile mixed with 5 mM ammonium acetate solution (pH=6.62) (60:40, v/v), ionized by negative ion pneumatically assisted electrospray and detected in the multi-reaction monitoring mode using precursor→product ions of m/z 354.1→222.2 for nifedipine and 150.1→107.1 for the IS. A single oral dose of 20 mg nifedipine sustained release tablets and blood samples (4 mL) was collected before and 1, 2, 2.5, 3, 3.5, 4, 4.5, 5, 6, 8, 12, 24, and 36 h after administration. The main pharmacokinetic parameters of nifedipine, as Tmax, t1/2α, t1/2β, t1/2z, Cmax, AUC0~36, AUC0~∞ were 2.80±0.50 h, 6.78±2.52 h, 6.82±2.53 h, 6.69±2.22 h, 76.69±19.51 (ng/mL), 546.49±162.28 (ng · h/mL) and 564.05±176.74 (ng · h/mL), respectively. The calibration curve was linear over the concentration range of 0.17-102 ng/mL (r2>0.99, n=5) with a lower limit of quantification (LLOQ) of 0.17 ng/mL. The intra- and inter-day precision was less than 15% for all quality control samples at concentrations of 0.42, 6.53 and 81.60 ng/mL and the accuracy (relative error, RE) was - 3.92% to 7.31% at 3 quality control levels. The specificity, matrix effect, recovery, sensitivity, linearity, accuracy, precision and stabilities were validated, and can fulfill the requirement of pharmacokinetic study of nifedipine sustained release tablets in Chinese volunteers.

Effects of degradable MG-ND-ZN-ZR alloy on osteoblastic cell function

This study aimed to investigate the effects of a novel patented Mg-3Nd-0.2Zn-0.4Zr (weight %, JDBM) alloy on osteoblastic cell function, as these cells play an important role in bone repair and remodeling. The associated effects of the JDBM alloy on osteoblastic cell function involving cell adhesion, cell proliferation, and mineralization were investigated using scanning electron microscopy (SEM), MTT assay and ambramycin staining, respectively. At the same time, the in vitro degradation behavior of the JDBM alloy in cell culture medium was evaluated by the weight-loss method and SEM. Pure magnesium was used as control. The results showed that osteoblastic cells cultured on JDBM alloy samples manifested better cell adhesion, improved cell proliferation and increased mineralization ability, compared with cells seeded on pure magnesium samples. Our data indicate that the JDBM alloy has excellent bioactivity, improving the cell function of osteoblastic cells seeded on it.

Pharmacokinetics of ginkgolide B injection in beagle dogs

A liquid chromatography-mass spectrometry method was developed, validated, and applied to the pharmacokinetic study with doses of 0.68, 2.73 and 10.92 mg/kg of ginkgolide B in beagle dogs after intravenous infusion.An aliquot of blood samples were -collected, separated and quantitatively analyzed by liquid chromatography-mass spectrometry method with mobile phase of acetonitrile-0.02% ammonia solution (33:67, v/v) at a flow rate of 0.8 mL/min on the UltimateTM XB-C18 column (5 μm, 4.6×150 mm).The method was sensitive, accurate and convenient, and can be used for the determination of ginkgolide B in beagle dogs. The Cmax and AUC0-∞ of GB increased with dose escalation, but ANOVA analyses showed that no significant difference was observed in other pharmacokinetic parameters between different doses.An LC/MS method was developed with good sensitivity, reproducibility and specificity. In the pharmacokinetic study of GB in beagle dogs, linear pharmacokinetics was found at doses from 0.62 to 10.92 mg/kg after a single-dose intravenous infusion. Gender differences were not observed in the pharmacokinetics of GB.

Measurement of the proton-air cross section at √s=57 TeV with the Pierre Auger Observatory

We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505±22(stat)(-36)(+28)(syst)] mb is found.

BMP activity is required for tooth development from the lamina to bud stage

Several Bmp genes are expressed in the developing mouse tooth germ from the initiation to the late-differentiation stages, and play pivotal roles in multiple steps of tooth development. In this study, we investigated the requirement of BMP activity in early tooth development by transgenic overexpression of the extracellular BMP antagonist Noggin. We show that overexpression of Noggin in the dental epithelium at the tooth initiation stage arrests tooth development at the lamina/early-bud stage. This phenotype is coupled with a significantly reduced level of cell proliferation rate and a down-regulation of Cyclin-D1 expression, specifically in the dental epithelium. Despite unaltered expression of genes known to be implicated in early tooth development in the dental mesenchyme and dental epithelium of transgenic embryos, the expression of Pitx2, a molecular marker for the dental epithelium, became down-regulated, suggesting the loss of odontogenic fate in the transgenic dental epithelium. Our results reveal a novel role for BMP signaling in the progression of tooth development from the lamina stage to the bud stage by regulating cell proliferation and by maintaining odontogenic fate of the dental epithelium.

Polymorphism of HMGA1 is associated with increased risk of type 2 diabetes among Chinese individuals

AIMS/HYPOTHESIS

Variants of the high-mobility group A1 (HMGA1) gene have been shown to be associated with insulin resistance and type 2 diabetes in individuals of European origin. We aimed to determine whether this locus confers significant susceptibility to type 2 diabetes in the Han Chinese population, and thus cross-race susceptibility to type 2 diabetes.

METHODS

Polymorphisms in HMGA1 were identified by direct sequencing of genomic DNA derived from 192 Chinese participants (96 patients with type 2 diabetes and 96 controls). We then genotyped the common variant IVS5-13insC (c.136-14_136-13insC) in two other independent cohorts, including a total of 2,533 cases and 2,643 ethnically matched controls.

RESULTS

We confirmed the association of the HMGA1 variant IVS5-13insC (c.136-14_136-13insC) with type 2 diabetes with an OR of 1.34 (95% CI 1.15, 1.56, p = 0.0002 under a dominant model, and 95% CI 1.16, 1.55, p = 0.0002 under an additive model) in the Han Chinese population, corresponding to a population attributable risk fraction of 5.0%.

CONCLUSIONS/INTERPRETATION

HMGA1 is an important susceptibility locus that confers a high cross-race risk of the development of type 2 diabetes.

Determination of norcantharidin in mouse tissues by liquid chromatography coupled to tandem mass spectrometry and its tissue distribution study

The purpose of this study is to determine the concentrations of norcantharidin (CAS NO: 5442-12-6) in mouse tissues and investigate its tissue distribution after intragastric administration of disodium norcantharidate solution. A highly sensitive and specific liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated, using ribavirin (CAS NO: 36791-04-5) as the internal standard (IS). Norcantharidin and IS were extracted from 0.3 mL tissue homogenates using protein precipitation with acetone under acid condition. The analyte was separated on a C18 reverse phase column and analyzed by MS/MS in the multiple reaction monitoring (MRM) mode using ESI with positive ionization, m/z 169→123 for norcantharidin and m/z 267→135 for IS. The developed method was validated over a linear range of concentrations 0.01~5 μg·mL - 1 in liver, lung, kidney, stomach, small intestine, uterus and testis, 0.005~0.5 μg·mL - 1 in heart, spleen and brain, the correlation coefficients (r2) were between 0.9918 and 0.9976. The tissue distribution study result was as follows: The AUC0-t of norcantharidin in tissues was in the order as follows: small intestine, stomach, uterus, kidney, testis, liver, lung, spleen, heart, brain.

Pharmacokinetic and bioequivalence studies of trospium chloride after a single-dose administration in healthy Chinese volunteers

The study aimed to compare and evaluate the bioequivalence of a new generic preparation of trospium chloride (CAS NO:10405-02-4) capsule (20 mg, test) and the available import tablet (20 mg , reference) for the requirement of state regulatory criteria in China. A randomized- sequence, 2-period crossover study was conducted in 20 healthy Chinese male volunteers in the fasted state. Blood samples were collected before and 1, 2, 3, 4, 5, 6, 7, 8, 12, 24, 36, 48, 60 h after administration of a single oral dose of 40 mg trospium chloride capsules or tablets, followed by a 7-day washout period. The concentration of trospium chloride was determined by a LC-MS/MS method. Drug And Statistical-Version 2.0 was used to calculate the pharmacokinetics parameters and assess bioequivalence of the two preparations. It was considered bioequivalent if the 90% CIs of the mean ratios (test: reference) for Cmax, AUC0-t and AUC0-∞ were within the range from 80% to 125%, respectively. The main pharmacokinetics parameters of test and reference were as follows: t1/2 was (15.11 ± 3.24) h and (16.00 ± 3.96) h; Tmax was (4.0 ± 1.2) h and (4.1 ± 0.9) h; Cmax was (3.76 ± 1.87) ng·mL - 1 and (3.70 ± 1.89) ng·mL - 1; AUC0-t was (33.51 ± 14.39) ng·mL - 1·h and (33.33 ± 14.88) ng·mL - 1·h, and the AUC0-∞ was (35.20 ± 14.88) ng·mL - 1·h and (35.16±15.17) ng·mL - 1·h. The ratios (test: reference) for Cmax, AUC0-t, and AUC0-∞ were 94.0%~111.7%, 96.4%~106.8%, and 96.1%~105.3%, respectively. No significant differences in pharmacokinetic parameters were found between preparations and periods (p>0.05). No obvious adverse events were monitored throughout the study based on clinical parameters and patient reports.

Metabolism and disposition of tribendimidine and its metabolites in healthy Chinese volunteers

Background: Tribendimidine is a new anthelmintic agent synthesized by Chinese scientists. It is a broad spectrum agent with high activity against parasites. However, its disposition and metabolism remain unknown.

Objective: To investigate the metabolism, disposition, and metabolites of tribendimidine in healthy human volunteers.

Methods: Twelve healthy Chinese volunteers were chosen after clinical assessment of health status and laboratory tests. They received single oral doses of tribendimidine 400mg enteric-coated tablets. Blood and urine samples were collected at scheduled timepoints. Samples were qualitatively and quantitatively analyzed by liquid chromatography-mass spectrometric (LC-MS) and high performance liquid chromatography (HPLC) methods, respectively.

Results: Tribendimidine was rapidly and completely broken down to p-(1-dimethylamino ethylimino) aniline (dADT) and terephthalaldehyde (TPAL). Furthermore, dADT was partially transformed to acetylated dADT, and TPAL completely transformed to terephalic acid (TPAC). The main pharmacokinetic parameters (± SD) of dADT were as follows: elimination half life (t_1/2) 4.74 ± 1.80 h; elimination rate constant (K_e) 0.16 ± 0.06 h⁻¹; apparent volume of distribution (Vd/F) 12.23 ± 8.69L • kg⁻¹; apparent total clearance of the drug from plasma (CL/F) 1.63 ± 0.58L • h⁻¹ • kg⁻¹; area under the plasma concentration-time curve (AUC) from time 0 to time 24 hours (AUC₂₄) 4.29 ± 1.88 μg • mL⁻¹ • h; AUC from time zero to infinity (AUC_∞) 4.45 ± 1.81 μg • mL⁻¹ • h; maximum plasma drug concentration (C_max) 0.64 ± 0.27 μg • mL⁻¹; and time to C_max (t_max) 4.20 ± 0.71 h. A total of 35.28% dADT and 28.50% TPAC were excreted through the urine within 24 hours after tribendimidine administration.

Conclusion: These results reveal the disposition, metabolism, and main metabolites of tribendimidine in healthy Chinese volunteers.