ABSTRACT
Nafamostat mesylate is a serine protease inhibitor used in the treatment of acute pancreatitis. The im-purities in nafamostat mesylate, the active pharmaceutical ingredient (API), were profiled via high performance liquid chromatography tandem ion trap coupled with time-of-flight mass spectrometer (HPLC-IT-TOF/MS). The chromatography was performed on an ACE-3 C18 column (200 mm × 4.6 mm, 3μm) using methanol and 0.1％ formic acid in purified water as mobile phase at a flow rate of 1.0 mL/min. The ions were detected by IT-TOF/MS with a full-scan mass analysis from m/z 100 to 800. In total, eleven impurities were detected in nafamostat mesylate API. The impurity profile was estimated based on the HPLC-IT-TOF/MS data, including accurate masses, MSn fingerprints of fragmentation pathways and a series of double-charged ions. Finally, seven impurities were identified and reported for the first time. The results will provide technical support for the quality control and clinical safety of nafamostat mesylate.
ABSTRACT
Electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) techniques for liquid chromatography–tandem mass spectrometry (LC–MS/MS) determination of levonorgestrel were evaluated. In consideration of difference in ionization mechanism, the two ionization sources were compared in terms of LC conditions, MS parameters and performance of method. The sensitivity for detection of levonorgestrel with ESI was 0.25 ng/mL which was lower than 1 ng/mL with APCI. Matrix effects were evaluated for levonorgestrel and canrenone (internal standard, IS) in human plasma, and the results showed that APCI source appeared to be slightly less liable to matrix effect than ESI source. With an overall consideration, ESI was chosen as a better ionization technique for rapid and sensitive quantification of levonorgestrel. The optimized LC–ESI–MS/MS method was validated for a linear range of 0.25–50 ng/mL with a correlation coefficient≥0.99. The intra-and inter-batch precision and accuracy were within 11.72%and 6.58%, respectively. The application of this method was demonstrated by a bioequivalence study following a single oral administration of 1.5 mg levonorgestrel tablets in 21 Chinese healthy female volunteers.
ABSTRACT
A sensitive and selective method using high-performance liquid chromatography coupled with elec-trospray ionization tandem mass spectrometry (HPLC–ESI–MS) to determine the concentration of tor-asemide in human plasma samples was developed and validated. Tolbutamide was chosen as the internal standard (IS). The chromatography was performed on a Gl Sciences Inertsil ODS-3 column (100 mm ? 2.1 mm i.d., 5.0 mm) within 5 min, using methanol with 10 mM ammonium formate (60:40, v/v) as mobile phase at a flow rate of 0.2 mL/min. The targeted compound was detected in negative io-nization at m/z 347.00 for torasemide and 269.00 for IS. The linearity range of this method was found to be within the concentration range of 1–2500 ng/mL (r?0.9984) for torasemide in human plasma. The accuracy of this measurement was between 94.05%and 103.86%. The extracted recovery efficiency was from 84.20% to 86.47% at three concentration levels. This method was also successfully applied in pharmacokinetics and bioequivalence studies in Chinese volunteers.
ABSTRACT
Objective To investigate the clinical value of simplified Chinese version NU-DESC in assessment of ICU delirium in domestic ICU,and provide easy ICU delirium assessment tool for clinical nurses.Methods We used simplified Chinese version NU-DESC to assess patients in domestic ICU from July to September 2011,and compared with the gold standard DSM-IV diagnosis results.Their validity,reliability and effectiveness were evaluated to analyze the application value of NU-DESC in ICU.Results The area under the ROC curve of simplified Chinese version of Nu-DESC was 0.951,the sensitivity was 82％,the specificity was 90％,the false negative rate was 18％,the false positive rate was 10％,Youden's index was 0.72,the positive likelihood ratio was 7.99,the negative likelihood ratio was 0.20,the agreement rate was 87％,Kappa value was 0.71,the positive predictive value was 77％,the negative predictive value was 92％.Conclusions The simplified Chinese version NU-DESC can easily be understood,used and accepted by nurses.They can be used as an assessment tool for nurses to judge ICU delirium for ICU patients.
ABSTRACT
[Objective]To discuss the reductive method and clinical result of lower cervical bilateral facet dislocation.[Method]Totally 22 cases with lower cervical bilateral facet dislocation were treated from 2000 to 2006.According to resecting the injuried disc annulus pre-reduction or not,the patients were divided to 2 groups.The variation of neurological fauction level were classified according to ASIA grade system.Among 13 cases examined by MRI,There were disc herniated in 9 cases(69%).[Result]The average time of follow-up was 18 months.Neurological symptom became more severe in 1 cases which injured disc annulus weren't resected in-reduction and in 3 cases which injured disc weren't resected post-reduction.ASIA grade deteriorated: 1 case upgraded from C to A,1 case upgraded from C to B,2 case upgraded C to D.But no one occurred in another group.[Conclusion]A lot of lower cervical bilateral facet dislocations have associated disc herniations.If injured disc isn't resected,the neurological symptom may become more severe.Resection injured disc,reduction,bone grafting can be settled in one time,in order to avoid secondary spine cord injury.