Functionalized bio-artifact fabricated via selective slurry extrusion. Part 2: Fabrication of ceramic dental crown.

Functionalized ceramic dental crown was successfully fabricated through selective slurry extrusion (SSE) based technique of solid freeform fabrication (also known as rapid prototyping). After sintering, the decomposed tourmaline powders were embedded in ZrO2 matrix. The far infrared emission properties of the ceramic dental crown were improved due to the increase of the numbers of infrared active bonds from tourmaline. This new dental restoration process presents potential to provide dental patients with functionalized artificial teeth, which benefits the body health by the way of emitting far infrared rays in ambient temperatures.

Rapid determination of tramadol in human plasma by headspace solid-phase microextraction and capillary gas chromatography-mass spectrometry.

A simple, rapid and sensitive method for determination of tramadol in plasma samples was developed using headspace solid-phase microextraction (HS-SPME) and gas chromatography with mass spectrometry (GC-MS). The optimum conditions for the SPME procedure were: headspace extraction on a 65-microm polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber; 0.5 mL of plasma modified with 0.5 mL of sodium hydroxide (0.1 M); extraction temperature of 100 degrees C, with stirring at 2000 rpm for 30 min. The calibration curve showed linearity in the range of 1-400 ng mL(-1) with regression coefficient corresponding to 0.9986 and coefficient of the variation of the points of the calibration curve lower than 10%. The detection limit for tramadol in plasma was 0.2 ng mL(-1). The proposed method was successfully applied to determination of tramadol in human plasma samples from 10 healthy volunteers after a single oral administration.

[Pharmacokinetics and bioavailability of clinafloxacin in rats].

AIM: To study the pharmacokinetics and bioavailability of clinafloxacin in rats. METHODS: The drug concentration was determined by HPLC. The main pharmacokinetic parameters were obtained by 3P87 program. An RP-C18 was used as the stationary phase. The mobile phase was a mixture of acetonitrile-0.05 mol.L-1 citric acid triethylamine (pH 2.5) (20:80). The flow rate was 1.0 mL.min-1. The UV absorbance detector was set at 300 nm. RESULTS: A good linearity was obtained from 0.03-20 micrograms.mL-1 of clinafloxacin in rat plasma with gamma = 0.9998. The plasma concentration--time curve of clinafloxacin conformed to one compartment open model. After ig administration of 50 mg.kg-1 and 100 mg.kg-1 dose of clinafloxacin in six rats, mean Cmax and AUC values increased in proportion to dose. Mean T1/2 appeared to be independent of dose. Mean AUC was 65 +/- 6 and 27 +/- 4 micrograms.h.mL-1 respectively after i.v. and ig administration of 100 mg.kg-1 dose. The extent of bioavailability (F) of clinafloxacin was 42%. CONCLUSION: The results of the pharmacokinetic study of clinafloxacin showed that it exhibited first order kinetic characteristics and the bioavailability is low.

Development of a sensitive and rapid liquid chromatography/tandem mass spectrometry method for the determination of apomorphine in canine plasma.

A sensitive, rapid and specific quantitative liquid chromatography/tandem mass spectrometry (LC/MS/MS) method was developed and validated for the determination of apomorphine (APO) in canine plasma. The analytes were prepared using one-step liquid-liquid extraction, and analyzed on a Waters Symmetry C(18) column interfaced with triple quadrupole tandem mass spectrometer. A mixture of methanol/0.1% formic acid in water (70: 30, v/v) was employed as the isocratic mobile phase. Positive electrospray ionization was utilized as the ionization source. The analyte and clenbuterol (internal standard) were both detected using multiple reaction monitoring (MRM) mode. The limit of detection (LOD) obtained was 0.03 ng/mL. The assay was linear over the concentration range of 0.1-100 ng/mL, and provided good precision (RSD) and good accuracy (RE). The analyte was stable by using antioxidants throughout the whole study. The experimental results show that LC/MS/MS is a rapid and sensitive method to analyze APO in plasma. Finally, the proposed method was successfully applied to a pharmacokinetic study of APO after intranasal administration of 0.5 mg apomorphine to 10 healthy beagle dogs.

Basic fibroblast growth factor enhanced LAK cell cytotoxicities against human bladder neoplasm cells.

AIM: To study the effects of basic fibroblast growth factor (bFGF) on the proliferation of lymphokine-activated killer (LAK) cells from patients with bladder cancer and LAK cells cytolysis against bladder tumor cells. METHODS: LAK cell proliferation was assayed in the presence of various concentrations of bFGF combined with interleukin-2 (IL-2) by cell count. Cytotoxicity of LAK cells against bladder cancer cell line EJ cells and bladder tumor cells (BTC) from patients was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. RESULTS: The proliferation of peripheral blood monocytes (PBMC) was inhibited by bFGF 5 micrograms.L-1. bFGF did not affect the stimulation of LAK cells induced by IL-2. The LAK cell numbers in the combination of IL-2 with bFGF were not significantly different compared with that treated with IL-2 alone. bFGF enhanced cytotoxicity of LAK cells against bladder cancer cell line EJ cells or BTC, respectively. CONCLUSION: Although the proliferation of PBMC was inhibited by bFGF, bFGF increased LAK cell cytotoxicity against bladder neoplasm cells.