With the advance of drug development and research techniques, the drug metabolic processes and mechanism can be more deeply achieved. As the drug metabolism and pharmacokinetics process are mediated by drug metabolizing enzymes and transporters, study of drug metabolizing enzymes and transporters has become an important part for drug development. The traditional immunoassays with low sensitivity and poor specificity can not reflect the accurate expression level of drug metabolizing enzymes and transporters. We now give a brief review on the quantitative study of drug metabolizing enzymes and transporters by mass spectrometry-based proteomic approach.
Enzymes ; chemistry ; Humans ; Inactivation, Metabolic ; Mass Spectrometry ; Membrane Transport Proteins ; chemistry ; Pharmacokinetics ; Proteomics

The fragmentation pathways of two taxanes drugs have been studied in positive ion mode by Q-TOF with the advantages of high mass accuracy and high resolution analysis. The [M+H] + ions were observed by ESI-MS, from which the molecular weights were obtained. Using the protonated pseudo-molecular ions [M+H]+ as internal reference compounds, the accurate mass and element composition of the fragment ions were determined. The collision induced dissociation (CID) data of the [M+H] ions provided fragmentation pathways of related compounds. Results showed that the major cleavage pathways of paclitaxel and docetaxel were the same that the cleavage of C-O bond between the side chain and taxol skeleton easily occurred, then stripping of the functional groups on the parent ring. Some common fragments were formed, such as m/z 105.033 7, 291.137 3, 309.148 5, 327.159 7, 387.181 2 and 509.217 4, which would provide a basis for future qualitative and quantitative analysis of taxanes in vitro and in vivo.
Paclitaxel ; chemistry ; Peptide Fragments ; chemistry ; Spectrometry, Mass, Electrospray Ionization ; methods ; Taxoids ; chemistry

The fragmentation pathways of five estrogens (estradiol, estrone, equilin sulfate, 17 a-dihydroequilin sulfate and equilenin sulfate) have been studied with high resolution and high mass accuracy using electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-Q-TOF/MS) in the negative ion mode. Molecular weights were obtained from [M-H](-) ions in the product ion spectra. The results indicate that the five structurally similar estrogens have similar fragmentation pathways. Using their stable isotope forms as internal reference compounds, the accurate mass and composition of the fragment ions were determined. During collision-induced dissociation (CID), cleavage is initiated by loss of oxygen atoms from carbon-17, after which D and C rings cleave sequentially and rearrange to finally form stable conjugate structures with highly abundant characteristic fragment ions at m/z 183 (accompanied by m/z 181), m/z 169 and m/z 145 (accompanied by m/z 143). Understanding these characteristic fragmentation pathways of estrogens will be helpful in identifying the structures of steroid hormones in general.
Chemical Fractionation ; methods ; Equilenin ; chemistry ; Equilin ; analogs & derivatives ; chemistry ; Estradiol ; chemistry ; Estrogens ; chemistry ; Estrone ; chemistry ; Ions ; Spectrometry, Mass, Electrospray Ionization

Objective To explore the value of dual-phase contrast-enhancement multislice computed tomography (MSCT) in the assessment of acute myocardial infarction volume and perfusion in porcine models. Methods The distal left anterior descending coronary arteries of 5 pigs were balloon-occluded for 90 min and followed by reperfusion. MSCT was performed 1 min (early phase) and 5 min (delayed phase) after administration bolus of 100 mL of iodinated contrast material 30 min after reperfusion. On the same day, hearts were excised, sectioned in 8 mm short-axis slices, and stained with TTC. Infarction volume was defined as the sum of the hyper-enhanced area and surrounding hypo-enhanced area in all slices on delay enhanced phase of MSCT and the TTC-negative area on TTC staining slices. Infarction volume was expressed as percentage of total slice volume. Results Acute infarction detected by MSCT was characterized by early myocardial perfasion defects in the early phase of the contrast bolus (early defects) with surrounding residual defects and late enhancement observed in the late phase. Mean CT attenuation value of early defects was significantly different from CT attenuation value of remote myocardium [(213±55)HU vs (304±30)HU](P < 0.05), CT attenuation values of residual defects and late enhancement were also significantly different from those of remote myocardium [(360±75) HU vs (90±37) HU and (152±23) HU vs (190±37) HU, repectively](P < 0.01, P < 0.05). The mean infarction volume was (8.9± 1.0)% on MSCT and (9.2±1.4)% on TTC pathology images. The infarction volume assessed by MSCT compared well with TTC staining slices. Conclusion Acute reperfused myocardial infarction zone has specific enhancement pattens different to remote normal zone on dual phase MDCT, which is in good agreement with in vivo Trc pathology in the assessment of acute reperfused myocardial infarction shortly offer reperfusion.

Radiation-induced bystander effect (RIBE) refers to that irradiated cells release signaling factors and induce responses in nonirradiated cells.In other words, it is the communication between irradiated and nonirradiated cells by intracellular signals. RIBE could influence the efficacy of tumor radiotherapy, but also has potential risk to the normal tissues outside of radiation field. Studies have found that ionizing radiation can induce the alteration of miRNA expression not only in the irradiated cells but also in adjacent nonirradiated tissues, and miRNAs may play an important role in the regulation of signaling pathways between irradiated and nonirradiated bystander cells. This article reviewed the roles of miRNAs in RIBE.

The paper is aimed to provide a novel index, named as multidimensional spatial triangular area, for the evaluation of the release-absorption correlation of multiple component traditional Chinese medicines (TCMs). The applicability of the method was demonstrated by the example data. The method and standard practice for evaluation of the release-absorption correlation for western medicines with single compound could not be applied to TCMs with multiple components. The release percentage or absorption percentage of the multiple components for TCMs at the sampling time was a point in the multidimensional space. The area of the triangle formed byt the sequential three points represented the changing characteristics of the components' release and absorption kinetics. The side lengths of the triangle could be calculated from the spatial distances between each two of the sequential three points. Then the triangle area could be obtained by the side lengths. The in vitro release-in vivo absorption correlation of the multiple components could be represented by the correlation between the integrating values of the release triangle areas and that of the absorption triangle areas. The results of the examples indicated that the multidimensional spatial triangular area method could treat the multiple components in a holistic way, in line with the holism the hi he TCMs. Therefore, the multidimensional spatial triangular area method provided new methodology for the release-absorption correlation of the TCMs with multiple components.
Algorithms ; Chemistry Techniques, Analytical ; Drug Combinations ; Drugs, Chinese Herbal ; analysis ; isolation & purification ; pharmacokinetics ; Medicine, Chinese Traditional ; Plants, Medicinal ; chemistry

AIMTo isolate and identify a glucuronide metabolite of SFZ-47 [3H-1,2-dihydro-2-(4-methyl-phenylamino)methyl-1-pyrrolizinone], which is difficult to synthesize because it undergoes hydrolysis and intramolecular acyl migration at physiological pH, in rabbit urine.

METHODSTwo rabbits were ig 200 mg doses of SFZ-47. Urine was collected for 24 h, adjusted to pH 4.0 with acetic acid and lyophilized. The residues were reconstituted in 25 mL methanol and centrifuged at 5,000 r.min-1 for 10 min. The supernatant was filtered (0.45 micron) and then isolated with semi-preparative reversed phase HPLC. The eluent collected from individual peaks was evaporated by rotary evaporation and freeze-drying. Compounds were then identified with electrospray ion trap mass spectrometry and 1HNMR spectroscopy.

RESULTSThe 1HNMR and ESI-MSn results indicate that the metabolite is the 1-O-acyl beta-D-glucuronide conjugate of 4-(3H-1,2-dihydro-1-pyrrolizinone-2-methylamino) benzoic acid.

CONCLUSIONThis method was shown to be rapid and simple and gave excellent resolution from endogenous constituents in urine, and it is suitable for preparation of the glucuronide metabolites of SFZ-47 and its analogues.

Animals ; Anti-Inflammatory Agents, Non-Steroidal ; metabolism ; urine ; Chromatography, High Pressure Liquid ; Male ; Molecular Structure ; Pyrroles ; chemistry ; metabolism ; urine ; Rabbits ; Spectrometry, Mass, Electrospray Ionization

AIMTo investigate the fragmentation behavior of triazolobenzodiazepines and to develop a specific, sensitive and rapid LC/MSn assay for simultaneous determination of estazolam, alprazolam and triazolam in human urine.

METHODSAfter oral administration of a single 4 mg dose of the drugs to each of three healthy volunteers, urine samples were purified by solid-phase extraction, and then injected into an ODS column (150 mm x 4.6 mm) with a mobile phase of methanol-water (8:2) for LC/MSn analysis. The structures of estazolam, alprazolam and triazolam in human urine were identified by direct comparison of the observed mass spectra and the chromatographic retention time with those of the reference substance. The mass spectrometer (Finnigan LCQ) was operated in positive mode and in two scan modes including SIM and full scan MS/MS mode. The obtained mass spectra was analyzed assisted with the software Mass Frontier 1.0 for their fragmentation pathways.

RESULTSThe full scan MS/MS spectra of each compound gave characteristic fragment ions of [M + H - N2]+ and [M + H - Cl]+. The detection limit was below 0.5 ng.mL-1 for estazolam, alprazolam and triazolam in human urine.

CONCLUSIONThe method is useful in forensic and clinical toxicology in which unequivocal identification of eatazolam, alprazolam and triazolam is desired.

Alprazolam ; urine ; Anti-Anxiety Agents ; urine ; Chromatography, Liquid ; Estazolam ; urine ; Humans ; Male ; Spectrometry, Mass, Electrospray Ionization ; Triazolam ; urine

Due to the diversity of components within the traditional Chinese medicines (TCMs), the release profiles of the components in the TCM dosage forms vary dramatically and no quantification method is available to determine the variance yet. Based upon the principles of Kalman filter method, the authors defined a new parameter, relative chemomic error (epsilon), to evaluate the asynchronous nature of the components in TCMs, and a derivative parameter as synchronization factor (SF) to quantify the synchronicity of the chemome of the TCMs. The average synchronization factor (SF(av)) was accordingly derived to simultaneously quantify the release/dissolution profiles of the multi-components in TCMs. Randomly generated simulation data were processed to demonstrate the chemomic data processing and the methodology. The results indicated that the novel parameter epsilon was well correlated (r = 0.996 8) with the coefficient of variation from the conventional release profiles of all the components. As the asynchronicity was the intrinsic characteristics of the multi-component TCMs, the synchronicity might be a new target of quality control of TCMs. The methods established by this report can be used a quantitative tool for the evaluation of the chemomic release synchronization of TCMs.
Algorithms ; Chemistry Techniques, Analytical ; Drug Combinations ; Drugs, Chinese Herbal ; analysis ; chemistry ; Evaluation Studies as Topic ; Medicine, Chinese Traditional

OBJECTIVETo evaluate and analyze the mechanism of Pizhen for the treatment of patients with scapular muscle fasciitis.

METHODSOne hundred and sixteen patients were divided into two groups according to random number table method, 58 cases in the treatment group and 58 cases in the control group. After treatment, 109 patients were followed up, and 7 patients lost follow-up (2 cases in the treatment group and 5 patients in the control group). In the treatment group, there were 15 males and 41 females, with a mean age of (28.02 +/- 4.85) years; the course of disease ranged from 0.25 to 3 years; and the patients were treated by Pizhen once a week,and 2 weeks were one treatment course. In the control group, there were 19 males and 34 females, with a mean age of (27.23 +/- 4.54) years old; the course of disease ranged from 0.25 to 1 year; and the patients were treated by acupuncture massage instrument, 20 minutes at a time,once a day for 2 weeks. Soft tissue displacement and banana area were tested by a soft tissue tension tester, pressure value was measured by pressure measuring instrument, and VAS was recorded by pain visual analog scale record.

RESULTSThere were significant differences in tissue displacement, banana area, pressure value and VAS between two groups before and after treatment. The tissue displacement and pressure value in the treatment group were higher than those in the control group,while banana area and VAS were lower than those in the control group. In the treatment group, 30 patients healed, 13 patients got marked improvement, 12 good and 1 poor;while 16 patients healed, 19 patients got marked improvement,11 good and 7 poor in the control group. The therapeutic effects in the treatment group was better than that in the control group.

CONCLUSIONPizhen is an effective method to treat pain in patients with scapular muscle fasciitis by relaxing tendon of soft tissue around pain point of scapular and relaxing compress and stimulation of nerves.

Acupuncture Points ; Acupuncture Therapy ; instrumentation ; Adult ; Case-Control Studies ; Fasciitis ; therapy ; Female ; Humans ; Male ; Treatment Outcome ; Young Adult