OBJECTIVE To investigate the absorption characteristics and tissue distribution of silybin （Sy） nanocrystals prepared by two methods in different intestinal segments of rats. METHODS Sy nanocrystals （i.e. Sy-NS-G and Sy-NS-F） with comparable particle sizes were prepared using high-pressure homogenization and anti-solvent precipitation methods， respectively. Rats were randomly divided into three groups： Sy raw drug group， Sy-NS-G group， and Sy-NS-F group. Each group was further divided into three subgroups with low， medium， and high （60， 120， 180 μg/mL） mass concentrations （calculated based on Sy）， with 3 rats in each subgroup. The absorption rate constant （Ka） and apparent absorption coefficient （Papp） of Sy raw drug， Sy-NS-G and Sy-NS-F in different intestinal segments were investigated by using the in vivo one-way intestinal perfusion experiment. Additionally， the rats were divided into three groups: Sy raw drug group， Sy-NS-G group， and Sy-NS-F group， with 20 rats in each group. Rats in each group were administered a single intragastric dose of 50 mg/kg （calculated based on Sy）. They were sacrificed at 0.3， 1， 4， 10， and 24 hours post-administration respectively， to investigate the tissue distribution of Sy raw drug， Sy- NS-G， and Sy-NS-F in the heart， liver， spleen， lungs， kidneys， brain and intestines. RESULTS In duodenum and jejunum， the Ka and Papp of the nanocrystals prepared by the two methods remained unchanged with the increase of Sy concentration， and there was no significant difference （P＞0.05）； the absorption of Sy-NS-F in the duodenum was greater than that of Sy-NS-G； the absorption sites of Sy-NS-G and Sy raw drug were mainly in the ileum， while those of Sy-NS-F were mainly in the duodenum and ileum. The concentrations of Sy-NS-G and Sy-NS-F in different tissues of rats were different； Sy-NS-G peaked in most tissues at 1 h， and the distribution concentration was as follows： intestine＞spleen＞heart＞lungs＞liver≈brain＞kidneys. Sy-NS-F reached its peak at 1 h， and the distribution concentration was in the order of intestine＞spleen＞kidney＞lung＞heart≈liver＞brain. CONCLUSIONS The absorption mode of Sy nanocrystals in the duodenum and ileum is mainly passive diffusion. In the duodenum， the absorption of Sy-NS-F is greater than that of Sy-NS-G； there are significant differences in the tissue distribution of Sy-NS-G and Sy-NS-F in rats.

【Objective】 To study the molecular mechanism of 95 samples of serological ABO subtypes. 【Methods】 A total of 95 samples with discrepancy between forward and reverse blood grouping were subjected to serological confirmation, and genotyped by polymerase chain reaction with sequence-specific primers (PCR-SSP). For those subtype alleles could not be detected by PCR-SSP, ABO gene exon 1-7 sequencing and gene single strand sequencing were performed successively to determine the mutation site and the gene location. 【Results】 A total of 34 ABO alleles were detected in 95 samples. Five common ABO alleles (ABO^*A1.01, ABO^*A1.02, ABO^*B.01, ABO^*O.01.01 and ABO^*O.01.02) and 29 rare ABO alleles were identified, including 16 named alleles by ISBT (ABO^*A2.01, ABO^*A2.05, ABO^*A2.13, ABO^*A3.07, ABO^*AW.37, ABO^*AEL.05, ABO^*B3.01, ABO^*B3.05, ABO^*BW.03, ABO^*BW.07, ABO^*BW.27, ABO^*BEL.03, ABO^*cisAB.01, ABO^*cisAB.05, ABO^*BA.02, ABO^*BA.04) and 5 named alleles by dbRBC(A223, B309, Bw37, Bel09, Bw40)and eight unnamed alleles [ABO^*B.01+ 978C>A, ABO^*A1.02+ 248A>T, ABO^*B.01+ 125dupT, ABO^*B.01+ (98+ 1G>A), ABO^*A1.02/ABO^*B.01+ 1A>G, ABO^*A1.02/ABO^*O.01.01+ 28G>T, ABO^*A1.02/ABO^*B.01+ 538C>T, ABO^*A1.02/ABO^*O.01.01+ 797insT] .The last four samples could not be verified by single strand because of insufficient samples. In 95 samples, 76 samples (21 named alleles of ISBT and dbRBC) were identified by PCR-SSP, and the remaining 19 samples were identified by exon 1-7 sequencing of ABO gene, of which 8 were identified as unnamed alleles, and the remaining 11 samples were not identified as subtype alleles. 【Conclusion】 The molecular genetic mechanism of 95 serological ABO subtypes was revealed, and 8 rare novel alleles were identified. The detection of ambiguous blood groups is influenced by factors such as patient pathology and physiology, therefore the combination of serological testing and genetic testing is suggested for the identification of ABO subtype.

OBJECTIVE To explore in vitro dissolution and in vivo pharmacokinetics of Luteolin solid dispersion in Beagle dogs. METHODS The dissolution of Luteolin solid dispersion was investigated according to the second method （paddle method） of the “dissolution determination method” in the 2020 edition of Chinese Pharmacopoeia （Part Ⅳ）. UPLC-MS/MS method was established to determine the concentration of luteolin in the plasma of Beagle dogs. Twelve Beagle dogs were randomly divided into luteolin group and Luteolin solid dispersion group， with 6 dogs in each group. They were given relevant medicine orally at the dose of 10 mg/kg luteolin. Blood was collected before medication （0 h）， at 5， 10， 15， 30， 45 min and 1， 2， 4， 6， 8， 10， 12， 24， 48 h after administration. After protein precipitation with acetonitrile， the blood concentration of luteolin in Beagle dogs was determined by UPLC-MS/MS and the major pharmacokinetic parameters were calculated with non-compartmental models by using DAS 3.2.8 pharmacokinetic software. RESULTS The dissolutions of Luteolin solid dispersion in purified water and 0.1% sodium dodecyl sulfate solution was significantly higher than those of luteolin； the dissolution rate reached 95% in 0.1% sodium dodecyl sulfate solution for 120 minutes. The peak concentration （cmax） of luteolin in the Luteolin solid dispersion group of Beagle dogs was 5.62 times higher than the luteolin group， and the relative bioavailability was 348%. Compared with luteolin group， cmax and the area under the drug time curve of luteolin in the Luteolin solid dispersion group of Beagle dogs were significantly increased， while the apparent distribution volume was significantly reduced （P＜0.05）. CONCLUSIONS Luteolin solid dispersion can improve in vitro dissolution and bioavailability of luteolin in Beagle dogs.

Objective To study the effect of storage duration on compressive mechanical properties of rabbit patellar, so as to provide references for in vitro ligament storage.Methods The compressive mechanical properties of rabbit patellar ligament storaged at -20 ℃ at different storage durations (in 36 d) were tested with the universal tensile test machine. The microscopic morphology of collagen fibers was observed under the scanning electron microscopy (SEM). The enthalpy and denaturation temperature of collagen fibers were measured with differential scanning calorimetry (DSC).Results With the increase of storage duration, the compressive stress of the patellar ligament at 40% strain increased from 19 kPa to 112 kPa and then decreased to 57 kPa. SEM observation showed that the cross-linking of collagen fibers was initially strengthened and then weakened. DSC results showed that the enthalpy increased from 59.47 J/g to 67.10 J/g and then decreased to 54.43 J/g. The denaturation temperature increased from 67.62 ℃ to 77.28 ℃ and then decreased to 64.10 ℃.Conclusions When rabbit patellar ligament is stored at -20 ℃, with the increase of storage duration, the compressive stress of rabbit patellar ligament at 40% strain increases at first and then decreases. This change may be due to the variation of cross-linking level of collagen fibers. The stronger the cross-linking of collagen fibers, the stronger the compressive mechanical properties will be.

Objective:To investigate the normal reference values of spinal bone mineral density measured by quantitative computed tomography (QCT) and the differences of bone mineral density (BMD) in different regions of in Chinese adult males.Methods:Men who underwent low-dose CT lung scan for cancer screening in regions of Northeast, North, East, South, Central and Southwest of China from January 2018 to December 2019 were selected. And the lumbar vertebrae BMD values in the male subjects were measured by the QCT system (Mindways Software, Inc.). The mean BMD values and their decline rates were calculated at an age interval of 10 years, and the prevalence of osteoporosis was calculated according to the American College of Radiology spine QCT osteoporosis diagnostic criteria.Results:A total of 50 682 males with a mean age of (50.22±12.79) years (ranged 20 to 98 years) were included in this study. The peak BMD of (173.11±28.56) mg/cm 3 in the healthy Chinese adult male population appeared in the age group of 20 to 29 years and then declined with age. Before the age of 70 years, the BMD was relatively higher in males in South China, and it was lower in Central China and Southwest China, and it was intermediate in Northeast, North and East of China, with statistically significant differences. There was no significant differences in BMD in the males in the two age groups of 70 to 79 years and 80 and older among the regions in China. The overall decline rate of spinal BMD in Chinese males under QCT was about 46.92% over the lifetime, and it declined obviouslyin the 40-49 age group. The overall prevalence of osteoporosis in Chinese male population aged 50 years and above was approximately 11.42%, with the highest prevalence in Southwest China and Central China (14.72% and 13.87%, respectively) and the lowest in North China and South China (8.53% and 7.71%, respectively). Conclusions:A reference of lumbar spine BMD values for healthy males in China based on QCT is established. BMD values were highest in South China and Lowest in Central China.

Objective:To establish the normal reference value of lumbar bone mineral density (BMD) under quantitative CT (QCT) in Chinese healthy adult females and to explore the regional differences.Methods:Total of 35 431 healthy women who met the inclusion criteria of Chinese health quantitative CT big data program were selected in this study. The BMD of the central plane of L 1 and L 2 vertebrae was measured by Mindways′s QCT system, and the mean value was taken. One-way analysis of variance was used to compare the BMD differences of lumbar vertebrae in women of different ages and regions. The subjects were grouped by an age interval of 10 years, and the level of BMD in different regions of the same age group were compaired. Results:The peak BMD of Chinese healthy adult women appeared in the age group of 20-29 years (Northeast China(183.01±24.58) mg/cm 3, North China (188.93±24.80) mg/cm 3, East China (187.54±27.71) mg/cm 3, South China (186.22±33.72) mg/cm 3, Central China (176.33±24.91) mg/cm 3, Southwest China(182.25±28.00) mg/cm 3), and then it decreased with age. The level of BMD in different regions decreased with the age. Before the age of 70 years, BMD in Central and Southwest China was always at a low level((176.23±24.91) to (90.38±28.12) mg/cm 3, 182.25±28.00 to (88.55±25.68) mg/cm 3), lower than those in Northeast China ((183.01±24.58) to (99.69±27.85) mg/cm 3), North China ((188.93±24.80) to (95.89±26.12) mg/cm 3), East China ((187.54±27.71) to (95.65±27.86) mg/cm 3). After 70 years of age, BMD tended to be the same in different regions ( P>0.05). The BMD values in Central China and Southwest China were similar in the age group of 40-60 years ( P>0.05). The BMD values in the health adult femles in the age group of 60 years in different regions of Chinawere all lower than those of bone mass abnormality (all P<0.05). The detection rate of osteoporosis in females over 50 years was the highest in Southwest China (25.65%) and it was the lowest in North China (17.30%). Conclusions:This study establishes reference values of BMD under QCT in healthy Chinese women, which can be used as a reference basis for identifying women with low BMD who are at risk of osteoporosis. The BMD value is the lowest in Southwest China and the highest in South China.

Objective:To use quantitative computed tomography (QCT) technology to measure the bone mineral density of the spine of the Chinese healthy population, and to explore its correlation with hemoglobin and serum albumin.Methods:The data in this study came from the China Health Quantitative CT Big Data Project (China Biobank). The spine bone density was measured by using QCT Pro Image Analysis System and all cooperating centers used the European spine phantom (NO.145) for quality control. Total of 50 053 healthy persons who met the criteria for entry were selected as the research subjects. The subjects were divided into 7 groups according to age. The general data, spine bone density, serum albumin, hemoglobin of the subjects were collected. The single-factor analysis of variance, Pearson correlation analysis and multi-classification logistic regression model were applied to analyze the correlation between bone density and hemoglobin and serum albumin.Results:The bone mineral density of healthy people decreased with age ( P<0.05), and there were significant differences in hemoglobin, serum albumin and body mass index (BMI) among different age groups (all P<0.05). Linear correlation analysis showed that there were positive correlation between bone mineral density and hemoglobin in healthy males in different age groups ( r=0.086, 0.101, 0.076, 0.090, 0.072, 0.123, 0.100, all P<0.01). There were negative correlation between bone mineral density and hemoglobin in certain age groups in women (40-49 years group: r=-0.027; 70-79 yearsgroup: r=-0.077; both P<0.05). And corelation were found between bone mineral density and serum levels of albumin in certain age groups of healthy subjects (among men, 30-39 years group: r=-0.048; 40-49 years group, r=-0.027; 70-79 years group, r=-0.051; among women, 30-39 years group: r=-0.044; 40-49 years group, r=-0.042; 50-59 years group, r=-0.086; 70-79 years group, r=-0.070; all P<0.05). After adjusting for age and BMI, the multi-category logistic regression analysis showed that the hemoglobin level was protective factor of normal bone density ( OR=1.022, 95% CI:1.017-1.027) and decreased bone density ( OR=1.012, 95% CI:1.007-1.016) in healthy males, and the serum albumin was risk factor for normal bone density ( OR=0.926, 95% CI:0.905-0.948) and decreased bone density ( OR=1.006, 95% CI:0.951-1.011) in healthy women. Conclusion:There is a correlation between bone mineral density and hemoglobin and serum albumin in Chinese healthy population. Hemoglobin is a protective factor for bone mineral density in men, and serum albumin is a risk factor for bone mineral densityin women.

objective:To evaluate the difference 24h energy expenditure in patients with multiple trauma mechanical ventilation predicted by indirect calorimetry (IC) and HB formula. To explore the correlation between energy expenditure and Injury Severity Scoring (ISS) in patients with multiple trauma, and to predict the stress coefficient to improve the accuracy of HB prediction.Methods:A total of 152 patients with multiple trauma receiving mechanical ventilation were included in the ICU of the General Hospital of Ningxia Medical University during December 1st, 2016 to August 31st, 2018. As a research object, The IC method and the HB method were used to simultaneously measure the patient's 24h energy expenditure, and the difference between the two measurement methods was compared. The 24h energy consumption measured by the IC method was used as the "gold standard", and the 24h body weight energy expenditure per kilogram was calculated; Grouped according to the ISS score, compared 24h energy consumption with 24h body weight energy expenditure per kilogram. The Bland-Altman method was used to test the consistency of the two measurements. The two groups were compared using t test, the correlation was analyzed by pearson correlation, and the regression equation was linearly calculated by linear regression.Results:There was a significant bias between the IC method and the HB method in measuring the 24h energy expenditure of patients with multiple trauma, with an average bias of 394.0± 54.0Kcal/d. The 24h energy consumption and 24h body weight energy expenditure per kilogram in the severe injured group were significantly higher than those in the moderate injury group ( P<0.05). The stress coefficient was calculated, The stress coefficient of the HB method associated with the ISS using the one-way regression was Y=0.770+0.018×ISS. Conclusion:The HB method significantly underestimates the 24h energy expenditure of patients with multiple trauma . In order to improve the accuracy of the HB method to predict the 24h energy consumption of patients with multiple injuries, The HB method can be corrected using the stress coefficient associated with the ISS score, Y = (0.770 + 0.018 × ISS) × HB method.

Objective:To evaluate the predictive effect of the 24 h energy expenditure value obtained by indirect calorimetry (IC) on the prognosis of patients with multiple traumatic mechanical ventilation.Methods:A total of 140 patients with multiple traumatic mechanical ventilation who were hospitalized in the ICU of General Hospital of Ningxia Medical University from December 1st, 2016 to August 31st, 2018 were selected as research objects. The general information such as sex, age, Height, weight, and clinical diagnosis were recorded. The IC method was used to measure the patient's 24 h energy expenditure, and the ratio of 24 h energy expenditure to the actual body weight of the patients was calculated the energy expenditure of 24 h energy expenditure per kilogram of body weight. The patient’s mechanical ventilation time and length of stay in ICU were statistically analyzed. The outcome indexes were 28-day mortality and the incidence of hospital-acquired infection. The receiver operating characteristic curve (ROC) was used to analyze the predictive value of 24 h energy expenditure and 24 h energy expenditure per kilogram of body weight.Results:The mechanical ventilation time was positively correlated with 24 h energy expenditure and 24 h energy expenditure per kilogram of body weight ( r=0.470, r=0.247, both P<0.01). The length of sty in ICU was positively correlated with the 24 h energy expenditure of patients with multiple trauma( r=0.276, P<0.05). The area under the ROC curve (AUC) of the 24 h energy expenditure and 24 h energy expenditure per kilogram of body weight for the 28 d mortality and the incidence of hospital-acquired infection were 0.647, 0.663, 0.832, 0.646, with the 24 h energy expenditure per kilogram of body weight greater than 30.4 kcal/(kg·d) as the best critical value for judging 28 d mortality. The sensitivity was 66.5%, specificity was 77.0%, and the 24 h energy expenditure consumption greater than 2 083 kcal/d was used as the optimal critical value for judging the susceptibility to acquire hospital infection, with a sensitivity of 80.0% and specificity of 80.7%. Conclusions:The mechanical ventilation time and length of stay in ICU are closely related to energy expenditure in patients with multiple trauma. The 24 h EE per kilogram of body weight and 24 h energy expenditure have a certain predictive effect on the prognosis of patients with multiple trauma.

Objective To explore the feasibility of the application of yak pericardium as anti-calcified heart valve materials in transcatheter aortic valve replacement (TAVR). Cattle pericardium and commercial Sino products were used as controls. Methods Yak and cattle pericardium was decellularized, and then the acellular extent was qualitatively and quantitatively analyzed with hematoxylin-eosin (HE) staining and DNA detection kit respectively. Two cross-linking agents, i.e. glutaraldehyde and genipin, were used to cross-link the acellular pericardium, respectively. After testing the mechanical property, thermodynamic stability and biocompatibility of the pericardium, the cross-linked pericardium was subcutaneously implanted in juvenile Wistar rats. After 2～4 weeks of the implantation, histological staining and tissue calcification analysis were conducted. Results The nuclei of the yak pericardium were almost invisible after decellularized treatment, and the DNA content decreased from (0.90±0.13)μg/mg to (0.09± 0.02)μg/mg that was significantly lower than that of Sino product (P<0.001). The mechanical strength of the acellular yak pericardium, glutaraldehyde or genipin cross-linked yak pericardium was higher than that of the cattle pericardium (all P<0.05). The maximum stress value, obtained in the glutaraldehyde cross-linked yak pericardium, was (8.44±2.61) MPa, which was higher than (7.92±1.81) MPa of the Sino product (P<0.05). The shrinkage temperature of non- and cross-linked yak pericardium was slightly higher than that of cattle pericardium, but difference was not statistically significant (all P>0.05). For the two cross-linked yak pericardium, the hemolysis rate and cell proliferation ratio was similar with that of cattle pericardium (all P>0.05), the tissue regeneration ability of subcutaneous implantations was inferior, and the calcification level was higher than that of cattle pericardium with an no statistically significant difference (all P>0.05). After 4 weeks of the subcutaneously implantation, the calcium content of the glutaraldehyde cross-linked pericardium was 32.62～65.49μg/mg. Conclusions Yak pericardium has better mechanical properties and thermodynamic stability than cattle pericardium, and the biocompatibility can meet the requirements of transcatheter aortic valve replacement.