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Vorapaxar,a novel antagonist of the protease-activated receptor 1 (PAR-1 ),can inhibit the clotting process. Deuterium-labeled vorapaxar was required for the analysis of clinical sample as an internal stand-ard. Starting for unlabeled vorapaxar,four-step reactions including hydrolysis,condensation,transesterification and hydrogen-deuterium exchange were carried out to synthesize [D8]vorapaxar effectively for the first time. All intermediates and final products were confirmed by NMR and high resolution mass spectrometry (HRMS).Impor-tantly,the prepared [D8]vorapaxar could meet the requirements of sample analysis as the internal standard.
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Siderophores were produced and secreted with marine microorganisms as the highly specific iron chelators. A method of liquid chromatography-tandem mass spectrometric detection coupled with solid phase extraction pretreatment was developed for the determination of siderophores in seawater. The samples were filtered through a 0. 22 μm membrane, extracted with an ENVI-18 cartridge and then eluted with methanol. The separation of the analytes was performed on a reversed phase SB-C18 column with a gradient elution program by using 0. 1% ( V/V) formic acid and methanol as the mobile phases. Qualitative analysis was performed in multiple-reaction monitoring mode. Good linearity (R2>0. 99) was obtained for Pyoverdines-Fe, Ferrichrome, Ferrioxamine E at the concentrations of 0. 001-3. 00 μg/mL, 0. 005-15. 00 μg/mL, 0. 001-3. 00 μg/mL, respectively. The instrumental detection limits and limits of quantification for the three analytes were 0. 08, 1. 76 and 1. 36 ng/mL; 0. 27, 5. 87 and 4. 53 ng/mL, respectively. The relative standard deviations were lower than 12%, while the recoveries were 12. 1%-18. 6% for Pyoverdines-Fe, 82. 0%-97. 7% for Ferrichrome, and 70. 0%-98. 3% for Ferrioxamine E.
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Objective To determine whether reduction In central pressure augmentation and central systolic blood pressure by nitroglycerine (NTG) results from effects on pre-lead or is due to arterial dilation. Methods We compared effects of NTG with these of lower body negative pressure (LBNP). Hemodyunmic measurements were made at rest, during LBNP (10, 20 and 30 mmHg, each for 15 min) and after NTG (10, 30 and 100μg/min, each dose for 15 min) in ten healthy volunteers. Cardiac pre-lead, stroke volume and cardiac output were assessed by echacardiography. Central pressure an mnentation and central systolic pressure were obtained by radial tonometry using a transfer function. Results LBNP (20 mmHg) and NTG (30μg/min) reduced pre-lead (as measured by the peak velocity of the S wave in the superior vena eava) to a similar degree [by (26. 8 ± 3.8) % and (23.9 ± 3. 4) %, respectively]. Compared to LBNP, NTG reduced systemic vascular resistance [by (32. 9 ± 7.5) %, p< 0. 01], decreased peripheral and central pressure augmentation [by (20. 8 ± 3. 4)% units and (12. 9±2. 9)% units, respectively, each P< 0. 01]. Conclusion These results suggest that a reduction in pre-load does not explain reduction in pressure augmentation and central systolic blood pressure by NTG and that these effects are mediated through arterial dilation.
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0.05). Conclude:The bone type may affect the stability of ITI osseointegrated implants.
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1. ③Higher examining rate of Ar wave was detected in acute phase in KD. ④V D was improved reversibly in convalescence phase. ⑤MVF showed that only E/A in acute phase in KD was lower than that of normal group. Conclusions It is available and valuable to combine PVF and MVF to assess left ventricular diastolic function in KD.
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This paper reports 9 cases of Marfan syndrome treated from 1984 to 1989. Among the 9 cases, 7 cases had abnormality, of eyes. 8 cases had abnormality of skeleton and 8 cases had abnormality in the cardiavescular system. 3 cases wer accompanied by angina pectoris. 1 case by SIE and thrombosis of aortic root was confirmed by autopsy in 1 case. The pathological process, prognosis and treatment of this syndrome have also been discussed briefly in the paper.