ABSTRACT
n-Octanol/ water partition coefficients (Kow ) is an important parameter commonly used to explain toxicity, activity and transmembrane of drugs. However, it is difficult to be detected by direct experimental determination. In this work, a set of 29 neutral and acidic analogues of naphthalene and anthraquinone with reliable experimental Kow data was chosen as model compounds for establishing linear relationship between the logarithm of apparent n-octanol/ water partition coefficient (lgKow), and the logarithm of reversed phase-high performance liquid chromatography (RP-HPLC) retention factor of the solutes corresponding to neat aqueous fraction of mobile phase (lgkw ) as the quantitative structure-retention relationship (QSRR) model. Methanol-water mixture was used as mobile phase at various pH, and retention time (tR ) was rectified by a dual-point retention time correction (DP-RTC) in this method. The experiment results indicated that the proposed QSRR model had good correlation coefficient R2 = 0. 974 -0. 976 with satisfactory results of internal and external validation (the cross-validated correlation coefficient R2cv of 0. 970-0. 973, and 1. 4% ≤relative error (RE)≤7. 9% for all the 6 verification compounds). In addition, this QSRR model was compared with linear solvation energy relationship ( LSER) involved in different descriptors of molecular structure, showing no differences. The QSRR model was applied to measure Kow of 11 naphthalenes and anthraquinones, and the predicted data were compared with Shake-flask method (SFM) experimental ones, as well as calculated ones obtained by software. The results suggested that the proposed method for Kow determination in this work was more accurate, simple and fast. To the best of our knowledge, this is the first report on measuring Kow data for these compounds. The proposed strategy provides the possibility in determining Kow of lipophilic components in complex mixture more quickly and accurately by RP-HPLC.
ABSTRACT
Objective: To identify Euryales Semen and its closely related species using the ITS2 barcode. Method:The total genomic DNAs were extracted from twenty samples of Euryales Semen and its closely related species. The ITS2 regions of the samples were amplified and bidirectional sequenced. Obtained sequences were submitted to the GenBank with Sequin 12.3. ITS2 sequences of 102 samples belonging to thirty species were downloaded from GenBank. The 122 ITS2 sequences were aligned and the genetic distances were analyzed with MEGA 5.1. Identification analyses were performed using BLAST1 and nearest distance methods, and were presented intuitively by constructing neighbor-joining (NJ) tree. Result: The length of ITS2 region of Euryales Semen was 214 bp, which was only one haplotype. There was significant divergence of the ITS2 regions among the samples. The NJ tree showed that Euryales Semen could be obviously differed from its closely related species, which had good 408 monophyly. Conclusion: ITS2 regions as a DNA barcode can stably and accurately distinguish Euryales Semen from its closely related species and also provide a new technique to ensure clinical safety in utilization of tradi-tional Chinese medicines. The new exploration could broaden the application of DNA barcoding technology in identification of Traditional Chinese Medicine.
ABSTRACT
Objective To analyze the effects of minimally invasive intenvention on acute suppurative cholangitis(ASC).Methods The clinical data of 28 patients with ASC and performed with endoscopic therapy were analyzed.Results 5 patients with a single stone incarcerated in the duodenal nipple were performed with ERCP and needle electrode fenestration to removed the stone.6 patients with a single stone were performed with endoscopic sphineterotomy(EST).15 patients are successfully performed with ERCP+EST after cholangitis and general situation turned better.2 patients failed with endoscopic therapy,and they were recovered treated with conventional surgery.Conclusion Minimally invasive intenvention on ASC has characteristics of quick,minimally invasive surgery,high success rate,rapid recover,and fewer complications.
ABSTRACT
In this study, daphnetin and its major metabolites in the intestinal wall of rats were identified by liquid chromatography and quatrupole-time of flight mass spectrometry. Perfusion fluid of duodenum, jejunum, ileum and colon were collected separately for 2 hours from the rat intestine following perfusion with daphnetin. The metabolites of daphnetin in the perfusion fluid of different intestine segments were analyzed by the liquid chromatography and quatrupole-time of flight mass spectrometry. It is shown that the parent drug daphnetin and four metabolites were found in the perfusion fluid of duodenum, jejunum and ileum. However, no metabolites were found in the colon. Among the four metabolites, two daphnetin sulfates (m/z 257) were first discovered as the phase II metabolites of daphnetin in rats, which revealed a new way of daphnetin metabolism in rats.