In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics. Similarities and variations of components present significant analytical challenges. A two-dimensional (2D) liquid chromatography-mass spectrometr (LC-MS) method was established for screening and comprehensive profiling of compositions of the antibiotic colistimethate sodium (CMS). A high concentration of phosphate buffer mobile phase was used in the first-dimensional LC system to get the components well separated. For efficient and high-accuracy screening of CMS, a targeted method based on a self-constructed high resolution (HR) mass spectrum database of CMS components was established. The database was built based on the commercial MassHunter Personal Compound Database and Library (PCDL) software and its accuracy of the compound matching result was verified with six known components before being applied to genuine sample screening. On this basis, the unknown peaks in the CMS chromatograms were deduced and assigned. The molecular formula, group composition, and origins of a total of 99 compounds, of which the combined area percentage accounted for more than 95% of CMS components, were deduced by this 2D-LC-MS method combined with the MassHunter PCDL. This profiling method was highly efficient and could distinguish hundreds of components within 3 h, providing reliable results for quality control of this kind of complex drugs.

To reduce the subjectivity and uncertainty present in the current international methods of drug value pricing when converting value into monetary prices,based on the hedonic pricing theory,it considers the post-negotiation price between manufacturers and payers as a reasonable price reference in the value pricing of Chinese patent medicine.By constructing an indicator system for the characteristics of Chinese patent medicine,it selects and measures the value characteristic variables that affect the price of Chinese patent medicine.It serves as the theoretical foundation and research basis for establishing a Hedonic price model between characteristic price variables and negotiation prices,thereby promoting the enhancement of rationality and objectivity in value-guided pricing of Chinese patent medicine.

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

To reduce the subjectivity and uncertainty present in the current international methods of drug value pricing when converting value into monetary prices,based on the hedonic pricing theory,it considers the post-negotiation price between manufacturers and payers as a reasonable price reference in the value pricing of Chinese patent medicine.By constructing an indicator system for the characteristics of Chinese patent medicine,it selects and measures the value characteristic variables that affect the price of Chinese patent medicine.It serves as the theoretical foundation and research basis for establishing a Hedonic price model between characteristic price variables and negotiation prices,thereby promoting the enhancement of rationality and objectivity in value-guided pricing of Chinese patent medicine.

To reduce the subjectivity and uncertainty present in the current international methods of drug value pricing when converting value into monetary prices,based on the hedonic pricing theory,it considers the post-negotiation price between manufacturers and payers as a reasonable price reference in the value pricing of Chinese patent medicine.By constructing an indicator system for the characteristics of Chinese patent medicine,it selects and measures the value characteristic variables that affect the price of Chinese patent medicine.It serves as the theoretical foundation and research basis for establishing a Hedonic price model between characteristic price variables and negotiation prices,thereby promoting the enhancement of rationality and objectivity in value-guided pricing of Chinese patent medicine.

To reduce the subjectivity and uncertainty present in the current international methods of drug value pricing when converting value into monetary prices,based on the hedonic pricing theory,it considers the post-negotiation price between manufacturers and payers as a reasonable price reference in the value pricing of Chinese patent medicine.By constructing an indicator system for the characteristics of Chinese patent medicine,it selects and measures the value characteristic variables that affect the price of Chinese patent medicine.It serves as the theoretical foundation and research basis for establishing a Hedonic price model between characteristic price variables and negotiation prices,thereby promoting the enhancement of rationality and objectivity in value-guided pricing of Chinese patent medicine.

To reduce the subjectivity and uncertainty present in the current international methods of drug value pricing when converting value into monetary prices,based on the hedonic pricing theory,it considers the post-negotiation price between manufacturers and payers as a reasonable price reference in the value pricing of Chinese patent medicine.By constructing an indicator system for the characteristics of Chinese patent medicine,it selects and measures the value characteristic variables that affect the price of Chinese patent medicine.It serves as the theoretical foundation and research basis for establishing a Hedonic price model between characteristic price variables and negotiation prices,thereby promoting the enhancement of rationality and objectivity in value-guided pricing of Chinese patent medicine.

To reduce the subjectivity and uncertainty present in the current international methods of drug value pricing when converting value into monetary prices,based on the hedonic pricing theory,it considers the post-negotiation price between manufacturers and payers as a reasonable price reference in the value pricing of Chinese patent medicine.By constructing an indicator system for the characteristics of Chinese patent medicine,it selects and measures the value characteristic variables that affect the price of Chinese patent medicine.It serves as the theoretical foundation and research basis for establishing a Hedonic price model between characteristic price variables and negotiation prices,thereby promoting the enhancement of rationality and objectivity in value-guided pricing of Chinese patent medicine.

To reduce the subjectivity and uncertainty present in the current international methods of drug value pricing when converting value into monetary prices,based on the hedonic pricing theory,it considers the post-negotiation price between manufacturers and payers as a reasonable price reference in the value pricing of Chinese patent medicine.By constructing an indicator system for the characteristics of Chinese patent medicine,it selects and measures the value characteristic variables that affect the price of Chinese patent medicine.It serves as the theoretical foundation and research basis for establishing a Hedonic price model between characteristic price variables and negotiation prices,thereby promoting the enhancement of rationality and objectivity in value-guided pricing of Chinese patent medicine.

To reduce the subjectivity and uncertainty present in the current international methods of drug value pricing when converting value into monetary prices,based on the hedonic pricing theory,it considers the post-negotiation price between manufacturers and payers as a reasonable price reference in the value pricing of Chinese patent medicine.By constructing an indicator system for the characteristics of Chinese patent medicine,it selects and measures the value characteristic variables that affect the price of Chinese patent medicine.It serves as the theoretical foundation and research basis for establishing a Hedonic price model between characteristic price variables and negotiation prices,thereby promoting the enhancement of rationality and objectivity in value-guided pricing of Chinese patent medicine.