Highly Efficient I2 Sorption, CO2 Capture, and Catalytic Conversion by Introducing Nitrogen Donor Sites in a Microporous Co(II)-Based Metal-Organic Framework.

Recently, the development of porous absorbents for efficient CO2 and I2 capture has attracted considerable attention because of severe global climate change and environmental issues with the nuclear energy. Hence, a unique porous metal-organic framework (MOF), {[Co(L)]·DMF·2H2O}n (1, DMF = N,N-dimethylformamide) with uncoordinated N atoms was rationally constructed via using a heterofunctional 4,6-bis(4'-carboxyphenyl)pyrimidine (H2L) linker. Interestingly, 1 exhibits exceptional properties for I2 sorption, CO2 capture, and catalytic conversion. Particularly, I2 can be efficiently removed in both vapor and solution forms, and the adsorption amount can reach 676.25 and 345.28 mg g-1, respectively. Furthermore, complex 1 displays high adsorption capacity for CO2 (53.78 cm3 g-1, 273 K). Consequently, 1 is expected to be a promising and practical material for environmental purification due to its excellent adsorption properties.

[Survival analysis on 3103 HIV/AIDS patients receiving antiretroviral treatment in Dehong prefecture, Yunnan province].

OBJECTIVE: To determine the survival rate of HIV/AIDS patients after receiving free antiretroviral treatment in Dehong prefecture, Yunnan province. METHODS: A retrospective cohort analysis was conducted on all the HIV/AIDS patients aged over 16 years who had started antiretroviral treatment during January 2007 throughout December 2009 in Dehong prefecture. RESULTS: A total of 3103 HIV/AIDS patients had received antiretroviral treatment during the study period. Among them, the mean age was (36.0 ± 9.9) years and 62.4% were males. 66.2% of them were infected with HIV through heterosexual transmission, and the mean treatment follow-up time was 21.7 months. Most patients well complied with the treatment, i.e., the average times of not taking the medicine were less than 5 per month. The cumulative survival rate of antiretroviral treatment after 1, 2, 3, 4, and 5 years were 0.95, 0.94, 0.93, 0.92, and 0.92, respectively. Data from the Cox proportional hazard regression model analysis indicated that, after adjustment for age, gender, and marital status, the baseline CD4(+)T cell counts and transmission route could significantly predicate the rates of survival. Those who were with baseline CD4(+)T cell counts as 200 - 350/mm(3)were less likely to die of AIDS than those with CD4(+) T cell counts < 200/mm(3) (Hazard Ratio or HR = 0.16, 95%CI: 0.09 - 0.28), and HIV-infected through mother-to-child transmission or routes other than heterosexual transmission were less likely to die of AIDS than through injecting drug use (HR = 0.35, 95%CI: 0.13 - 1.00). CONCLUSION: Free antiretroviral treatment had significantly improved the survival of HIV/AIDS patients. Earlier initiation of antiretroviral treatment was likely to have achieved better survival effects.

Development and validation of a liquid chromatography-tandem mass spectrometry method for the determination of xanthinol in human plasma and its application in a bioequivalence study of xanthinol nicotinate tablets.

A sensitive, rapid liquid chromatographic-electrospray ionization mass spectrometric method for the determination of xanthinol in human plasma was developed and validated. Xanthinol nicotinate in plasma (0.5 mL) was pretreated with 20% trichloroacetic acid for protein precipitation. The samples were separated using a Lichrospher silica (5 microm, 250 mm x 4.6 mm i.d.). A mobile phase of methanol-water containing 0.1% formic acid (50: 50, v/v) was used isocratically eluting at a flow rate of 1 mL/min. Xanthinol and its internal standard (IS), acyclovir, were measured by electrospray ion source in positive selected reaction monitoring mode. The method demonstrated that good linearity ranged from 10.27 to 1642.8 ng/mL with r=0.9956. The limit of quantification for xanthinol in plasma was 10.27 ng/mL with good accuracy and precision. The mean plasma extraction recovery of xanthinol was in the range of 90.9-100.2%. The intra- and inter-batch variability values were less than 4.8% and 7.9% (relative standard deviation, R.S.D.), respectively. The established method has been successfully applied to a bioequivalence study of two xanthinol nicotinate tablets for 20 healthy volunteers.

Simultaneous determination and pharmacokinetic study of roxithromycin and ambroxol hydrochloride in human plasma by LC-MS/MS.

BACKGROUND: Although roxithromycin and ambroxol HCl were often administered concomitantly for the treatment of respiratory infections, the pharmacokinetic interactions between them have not been reported. We investigated the interactions between these drugs in health male Chinese volunteers by LC-MS/MS in human plasma. METHODS: The pharmacokinetics were studied in 12 healthy male Chinese volunteers after an overnight fast by a single oral dose, 4-way crossover design with a period of 7-day washout. Each subjects was randomized to receive a single oral dose of 1 compound roxithromycin (150 mg) and ambroxol HCl (30 mg) dispersible tablet (test formulation, treatment A), one 150 mg roxithromycin dispersible tablet together with one 30 mg ambroxol HCl tablet (combined reference formulations, treatment B), one 150 mg roxithromycin dispersible tablet (reference formulation I, treatment C), or one 30 mg ambroxol HCl tablet (reference formulation II, treatment D) with 250 ml of water. Venous blood was collected at pre-dose (0 h) and 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 12, 24, 48, 72 h after dosing. The plasma concentrations of roxithromycin and ambroxol HCl were simultaneously determined by using a validated internal standard LC-MS/MS method. RESULTS: No significant differences were observed for the major pharmacokinetic parameters such as C(max), T(max), t(1/2) and AUC of both roxithromycin and ambroxol HCl between different treatments. CONCLUSION: The pharmacokinetics of both roxithromycin and ambroxol HCl are not affected by their concomitant oral administration. Therefore, there are no obvious pharmacokinetic interactions between roxithromycin and ambroxol HCl after oral administration. Roxithromycin and ambroxol HCl dispersible tablets were bioequivalent with reference to the roxithromycin dispersible tablets and ambroxol HCl tablets in combination usage.

Determination and pharmacokinetic study of oxymatrine and its metabolite matrine in human plasma by liquid chromatography tandem mass spectrometry.

There is little information about the pharmacokinetics of oxymatrine (OMT) and its metabolite matrine (MT) after i.v. administration of OMT in human. Therefore a specific and sensitive liquid chromatography tandem mass spectrometry (LC-MS/MS) method was established for the determination and pharmacokinetic study of OMT and its metabolite MT in human plasma after i.v. infusion administration of 600 mg of OMT in 100 ml of 5% glucose injection in 0.5 h. The analysis was carried out on a Lichrospher-CN column (250 mmx4.6 mm, i.d., 5 microm, Merck) with mobile phase of methanol-ammonium acetate (20 mmol/l; 85:15, v/v) pumped at a flow rate of 1.0 ml/min. The tandem mass detection was made with electrospray ionization in positive ion selected reaction monitoring mode, with argon collision-induced dissociation ion transitions m/z 265.2 to m/z 265.2 for OMT at 25 eV, m/z 249.2 to m/z 249.2 for MT at 25 eV and m/z 340.2 to m/z 324.0 at 35 eV for the internal standard (papaverine), respectively. The assay was validated to be accurate and precise for the analysis in the concentration range of 1.0-40,000 ng/ml for both OMT and MT with the LOD being 0.5 and 0.2 ng/ml, respectively, when 0.25 ml of human plasma sample was processed with papaverine as internal standard. The pharmacokinetic study was made with 10 healthy male Chinese subjects. The plasma concentration time profiles of OMT and MT obtained were best fitted with two-compartment and one-compartment models, respectively. The main pharmacokinetic parameters found for OMT and MT after i.v. infusion were as follows: Cmax (20,519+/-7581) and (247+/-45) ng/ml, Tmax (0.5+/-0.1) and (5.6+/-1.7) h, AUC0-t (20,360+/-5205) and (3817+/-610) ng h/ml, AUC0-infinity (20,436+/-5188) and (3841+/-615) ng h/ml, t1/2 (2.17+/-0.49) and (9.43+/-0.62) h, respectively. The CL/F and Vd/F of OMT were (43.8+/-10.8) l h-1 and (70.1+/-26.6) l, respectively. Therefore only a small amount of OMT was reduced to MT following i.v. administration of OMT judged by the AUCs.

Protective effects of bendazac lysine on early experimental diabetic nephropathy in rats.

AIM: To investigate the preventive and protective effects of bendazac lysine (BDL) on experimental early diabetic nephropathy (DN) rats. METHODS: After an early DN model was induced by streptozotocin, rats were administered BDL at doses of 100, 200, and 400 mg/kg for 8 weeks. Blood glucose, microalbuminuria, kidney index, total antioxidative capacity, laminin, advanced glycation end products (AGE), aldose reductase (AR) activity, and the relative quantity of transforming growth factor beta1 (TGF- beta1) mRNA were measured by different methods. The ultrastructural morphology was observed by transmission electron microscope. RESULTS: The physical behaviors of early DN rats were hypopraxia, cachexia, and polyuria, while those treated with high doses of BDL were vibrant and vigorous. For BDL-treated DN rats, when compared with vehicle-treated DN rats, the blood glucose level and the intensity of oxidative stress were ameliorated. Also, the microalbuminuria level, AGE either in serum or in renal, and AR activity were significantly reduced. Furthermore, the expression of TGF-beta1 mRNA in the kidney cortex was declined and the thickness of glomerular base membrane was decreased significantly. The ultrastructure of glomerulus and mesangial matrix of BDL-treated DN rats were ameliorated. CONCLUSION: BDL has protective effects on several pharmacological targets in the progress of DN and is a potential drug for the prevention of early DN.

[Pharmacokinetics of fudosteine in healthy volunteers].

AIM: To study the pharmacokinetics of fudosteine in healthy volunteers after the single and multiple dose administration. METHODS: Thirty-six volunteers were divided into three groups randomly, each group included six men and six women. In the single dose design, the volunteers received either a single dose of 600 mg, 400 mg or 200 mg fudosteine. After a one-week wash out period, the volunteers of 400 mg group participated in the multiple dose design in which each volunteer received 400 mg fudosteine three times a day for five consecutive days. The plasma concentrations were determined by pre-column derivatization HPLC-FL method and the pharmacokinetic parameters of fudosteine were calculated. RESULTS: The obtained pharmacokinetic parameters of fudosteine in single dose of 600 mg, 400 mg and 200 mg groups were as follows: T1/2 were (2.8 +/- 0.5), (2.7 +/- 0.5) and (3.2 +/- 0.6) h, respectively. T(max) were (0.51 +/- 0.22), (0.59 +/- 0.21) and (0.48 +/- 0.18) h, respectively. C(max) were (16 +/- 4), (11 +/- 3) and (6.1 +/- 1.5) microg x mL(-1), respectively. The AUC(0-10 h) and C(max) correlated linearly with doses, respectively (r > 0.99). The T(max), C(max) and AUC values of fudosteine in healthy male volunteers were smaller than those in female volunteers, and the T1/2 value was longer than that in female volunteers. The obtained multi-dose pharmacokinetic parameters of fudosteine were as follows: C(ss) was (4.1 +/- 0.8) microg x mL(-1); DF was 3.0 +/- 0.7; T1/2 was (2.5 +/- 0.4) h; T(max) was (0.6 +/- 0.3) h; C(max) was (13.2 +/- 1.3) microg x mL(-1). CONCLUSION: The values of pharmacokinetic parameters in healthy volunteers were linear in the range from 200 mg to 600 mg. Statistic analysis results showed that the differences of AUC and C(max) between men and women were not resulted from sexual differences, but from the weight differences. There was no significant difference in pharmacokinetic parameters between single dose and multi-dose.

[Pharmacokinetics and bioequivalence of eperisone hydrochloride tablet in healthy subjects].

AIM: To develop a HPLC-ESI-MS assay for determination of eperisone hydrochloride in human plasma and investigate the pharmacokinetics and bioequivalence of two eperisone hydrochloride tablets in human. METHODS: Buflomedil hydrochloride was used as the internal standard. After alkalized with saturated sodium bicarbonate solution, plasma was extracted with diethylether-cyclohexane (1:1) and separated using HPLC on a reversed-phase C18 column with a mobile phase of 10 mmol x L(-1) ammonium acetate buffer solution (adjusted to pH 3.88 with acetic acid)-methanol (20:80). HPLC-ESI-MS was performed in the selected ion monitoring (SIM) mode using target ions at m/z 260 for eperisone and m/z 308 for the internal standard. A randomized crossover design was performed in 20 healthy volunteers. In the two study periods, a single 100 mg dose of each tablet was administered to each volunteer. RESULTS: Calibration curve was linear over the range of 0.02-20 microg x L(-1). The limit of quantification for eperisone hydrochloride in plasma was 0.02 microg x L(-1). The main pharmacokinetics parameters T1/2, Tmax and Cmax were (2.7 +/- 0.4) h, (1.1 +/- 0.5) h and (2.8 +/- 2.8) microg x L(-1) for the reference tablet; (2.8 +/- 0.5) h, (1.1 +/- 0.4) h and (3 +/- 4) microg x L(-1) for the test tablet, respectively. The relative bioavalability of the test tablet was (101 +/- 13)%. CONCLUSION: The assay was proved to be sensitive, accurate and convenient. The two formulations were bioequivalent.

Effect of CYP2D6*10 genotype on propafenone pharmacodynamics in Chinese patients with ventricular arrhythmia.

AIM: To determine the effect of CYP2D6*10 genotype on propafenone pharmacodynamics in Chinese patients with ventricular arrhythmia. METHODS: Seventeen Chinese patients with ventricular premature contractions (VPC> or =1000/d) were recruited. They were normal in routine laboratory testing and administered propafenone hydrochloride 450-600 mg per day in three divided doses. Twelve lead cardiogram and 24 h Holter monitoring were performed before and after 7 d treatment of propafenone. Steady-state peak and trough concentrations of propafenone were measured by HPLC method. CYP2D6*10 genotypes of patients were assayed by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). RESULTS: Total inhibitory rate of VPC was 79.9 % in 17 patients with ventricular arrhythmia after propafenone treatment. PR interval prolongation was increased from 0.146 s+/-0.018 s to 0.161 s+/-0.022 s (P<0.05). CYP2D6 genotypes played an important role in plasma levels and effects of propafenone. In 450 mg/d group, patients with homozygous mutant of CYP2D6*10 not only had a Cmax of propafenone two times as high as those of wild-type genotype, but also showed a two fold higher inhibitory rate of VPC compared with those with homozygous CYP2D6*1 (P<0.05). CONCLUSION: CYP2D6*10 genotype is relevant to decreased activity of CYP2D6 enzyme in Chinese patients. Elevated plasma concentration is consistent with better efficacy of propafenone in patients with ventricular arrhythmia.