Objective To establish a stable,reliable,and clinically relevant porcine model of endotoxin-induced acute respiratory distress syndrome(ARDS).Methods Ten 8-month-old male Bama minipigs were deeply sedated,followed by invasive mechanical ventilation and electrocardiographic monitoring.Lipopolysaccharide(LPS)was intravenously pumped at 600 μg/(kg·h)for 3 hours,then maintained at 15 μg/(kg·h)thereafter.Dynamic monitoring was performed at five time points after LPS injection(LPS 0,1,3,5,and 8 h),including arterial blood gas analysis and chest computed tomography(CT)scans.Pathological examination of lung tissues obtained via bronchoscopic biopsy(HE staining and transmission electron microscopy)was conducted.These indicators were comprehensively used to evaluate the success of the animal model.Results At 5 hours after LPS administration,8 minipigs developed symptoms such as skin cyanosis,elevated body temperature,and respiratory distress.The oxygenation index decreased to<300 mmHg.Chest CT scans showed diffuse pulmonary infiltrates.Histopathology revealed alveolar edema and hyaline membrane formation.Transmission electron microscopy demonstrated disruption of pulmonary blood-air barrier,depletion of lamellar bodies in type Ⅱ pneumocytes,inflammatory cell infiltration,and exudation of plasma proteins and fibrin.Compared with LPS 0 h,at LPS 8 h,the oxygenation index and arterial blood pH were significantly decreased(P<0.001),while blood lactic acid and serum potassium were significantly increased(P<0.05);serum calcium and base excess were significantly decreased(P<0.05),and the lung injury score based on HE-stained lung sections was significantly increased(P<0.01).Conclusion The porcine ARDS model established by continuous LPS injection can dynamically simulate the pathophysiological characteristics and typical pathological manifestations of clinical septic ARDS,making it an effective tool to study the pathogenesis,prevention,and treatment strategies of septic ARDS.

OBJECTIVE: To investigate the incidence rate and risk factors for metabolic bone disease of prematurity (MBDP) in very low birth weight/extremely low birth weight (VLBW/ELBW) infants. METHODS: The medical data of 61 786 neonates from multiple centers of China between September 1, 2013 and August 31, 2016 were retrospectively investigated, including 504 VLBW/ELBW preterm infants who met the inclusion criteria. Among the 504 infants, 108 infants diagnosed with MBDP were enrolled as the MBDP group and the remaining 396 infants were enrolled as the non-MBDP group. The two groups were compared in terms of general information of mothers and preterm infants, major diseases during hospitalization, nutritional support strategies, and other treatment conditions. The multivariate logistic regression analysis was used to investigate the risk factors for MBDP. RESULTS: The incidence rate of MBDP was 19.4% (88/452) in VLBW preterm infants and 38.5% (20/52) in ELBW preterm infants. The incidence rate of MBDP was 21.7% in preterm infants with a gestational age of < 32 weeks and 45.5% in those with a gestational age of < 28 weeks. The univariate analysis showed that compared with the non-MBDP group, the MBDP group had significantly lower gestational age and birth weight, a significantly longer length of hospital stay, and a significantly higher incidence rate of extrauterine growth retardation ( CONCLUSIONS A lower gestational age, hypocalcemia, extrauterine growth retardation at discharge, and neonatal sepsis may be associated an increased risk of MBDP in VLBW/ELBW preterm infants. It is necessary to strengthen perinatal healthcare, avoid premature delivery, improve the awareness of the prevention and treatment of MBDP among neonatal pediatricians, and adopt positive and reasonable nutrition strategies and comprehensive management measures for preterm infants.
Birth Weight ; Bone Diseases, Metabolic/etiology* ; China/epidemiology* ; Female ; Humans ; Infant ; Infant, Extremely Low Birth Weight ; Infant, Newborn ; Infant, Premature ; Infant, Very Low Birth Weight ; Pregnancy ; Retrospective Studies ; Risk Factors

Cleistocalycis Operculati Cortex is the dry bark of Cleistocalyx operculatus. It is the raw material of Compound Hibiscuse which is external sterilization antipruritic drugs. The quality standard of Cleistocalycis Operculati Cortex in Guangdong Province "standard for the traditional Chinese medicine" (second volumes) only contains TLC identification. It is unable to effectively monitor and control the quality of Cleistocalycis Operculati Cortex. A reversed-phase HPLC method was established for the determination of 3, 3'-O-dimethylellagic acid from Cleistocalycis Operculati Cortex and the content was calculated by external standard method for the first time. Under the selected chromatographic conditions, the target components between peaks to achieve effective separation. 3,3'-O- dimethylellagic acid standard solution at the concentration of 1.00 - 25.0 mg x L(-1) showed a good linear relationship. The standard curve was Y = 77.33X + 7.904, r = 0.999 5. The average recovery was 101.0%, RSD was 1.3%. The HPLC method for the determination of 3,3'-O-dimethylellagic acid in Cleistocalycis Operculati Cortex is accurate and reliable. It can provide a strong technical support for monitoring the quality of Cleistocalycis Operculati Cortex.
Chromatography, High Pressure Liquid ; methods ; Chromatography, Reverse-Phase ; methods ; Drugs, Chinese Herbal ; analysis ; Plant Bark ; chemistry ; Syzygium ; chemistry