Objective To develop a low-oxygen mixed gas generator to make up for the deficiencies of low-pressure chambers and load-resistant hypoxia trainers during pilot hypoxia tolerance testing.Methods The device prepared the low-oxygen gas with the principle of gas separation,which was composed of a Sunsource OLF1100D-220AF air compressor,a SMC IDG75SAM4-03 filter,a buffer tank,an AIR Products PA3010 integrated assembly,a control box,sensors and regulators.The sensors included the pressure sensor,flow sensor,concentration sensor and dew point temperature sensor,and the control box consisted of a main control board,a power supply module,a transmission module,a communication module,a display and a housing.The embedded control software of the device was developed with KEIL 5 and C++.Results The device developed prepared the low-oxygen gas with the volume fraction being 4％to 18％and the maximum error of volume fraction being 0.05％,and the main components of the prepared gas met the technical requirements of medical oxygen as stipulated in GB 8982-2009 Oxygen supplies for medicine and aircraft breathing.Conclusion The low-oxygen gas prepared by the device has its volume fraction precisely controlled and can be used for hypoxia tolerance testing and acclimation training for pilots.[Chinese Medical Equipment Journal,2024,45(7):24-28]

During the storage process, Chinese medicinal materials are susceptible to insect infestation due to their own nature and external storage factors. Infestation by insects can have varying impacts on the materials. In mild cases, it affects the appearance and reduces consumer purchasing power, while in severe cases, it affects the quality, reduces medicinal value, and introduces impurities such as insect bodies, excrement, and secretions, resulting in significant contamination of the medicinal materials. This study reviewed the rele-vant factors influencing insect infestation in Chinese medicinal materials and the compositional changes that occur after infestation and summarized maintenance measures for preventing insect infestation. Additionally, it provided an overview of detection techniques applicable to identifying insect infestation during the storage of Chinese medicinal materials. During the storage process, insect infestation is the result of the combined effects of biological factors(source, species, and population density of insects), intrinsic factors(moisture, chemical composition, and metabolism), and environmental factors(temperature, relative humidity, and oxygen content). After infestation, there are significant changes in the content of constituents in the medicinal materials. By implementing strict pre-storage inspections, regular maintenance after storage, and appropriate storage and maintenance methods, the occurrence of insect infestation can be reduced, and the preservation rate of Chinese medicinal materials can be improved. The storage and maintenance of Chinese medicinal materials are critical for ensuring their quality. Through scientifically standardized storage and strict adherence to operational management standards, the risk of insect infestation can be minimized, thus guaranteeing the quality of Chinese medicinal materials.
Animals ; Drug Contamination/prevention & control* ; Insecta ; Preservation, Biological ; Temperature

Objective: To explore the differences in subsequent analysis between metagenomic and 16Sr DNA sequencing in compositionally characterizing gut microbiota of healthy elderly. Methods: By using a panel study design, five monthly repeated measurements were performed among 76 healthy older people in Jinan City, Shandong Province. Their fecal samples were collected, and genomic DNA was extracted and analyzed through metagenomic and 16Sr DNA sequencing to compare the composition and diversity of gut microbiota. The correlation between species abundance and α diversity was analyzed by Pearson correlation analysis, and the correlation between species abundance and β diversity was determined by Procrustes analysis. Results: The age of 76 participants was (65.07±2.75), and the body mass index was (25.03±2.40) kg/m². There were 38 males and 38 females. A total of 345 fecal samples were obtained from five monthly repeated measurements . Compared with 16S rDNA sequencing, metagenomic sequencing showed more annotated species at each level. The difference in the number of two sequencing species increased with the decrease of the level. Although there were significant differences in species richness between the two sequencing methods. Their species richness was highly correlated at both phylum (r=0.88, P<0.001) and genus (r=0.77, P<0.001) levels. Bacteroidetes and Firmicutes were the common dominant species. Gut microbiota diversity analysis further showed that there was a significantly positive correlation between α diversity (r=0.70, P<0.001) and β diversities (M²=0.84, P<0.05) in the two groups. Conclusion: The annotation efficiency of metagenomic sequencing is much higher than that of 16S rDNA sequencing. The two sequencing methods are consistent in phylum abundance as well as α diversity.
Male ; Female ; Humans ; Aged ; Gastrointestinal Microbiome/genetics* ; DNA, Ribosomal/genetics* ; Feces ; Sequence Analysis, DNA ; Metagenomics ; RNA, Ribosomal, 16S/genetics*

Objective: To establish an ultrahigh performance liquid chromatography tandem mass spectrometry method for the determination of creatinine (Cre) and 2-thiothiazolidine-4-carboxylic acid (TTCA) in urine. Methods: In October 2020, the end-of-shift urine samples of the monitored subjects were taken, and the filtrate was prepared by centrifugation. After separated by ultra high performance liquid chromatography C18 column, acetonitrile and 0.2% acetic acid aqueous solution were used as mobile phases for gradient elution, the three quadrupole tandem mass spectrometry adopted an electrospray ion source (ESI) , the ion source temperature was 500 ℃ , and the air curtain gas flow rate was 31.4 L/min, qualitative and quantitative analysis of Cre and TTCA were carried out under the multiple reaction monitoring mode. Results: The linear range of Cre was 1.0-1 000.0 μg/L, the linear equation was y=947.3x-1605.6, and the correlation coefficient was 0.9994. The detection limit and the limit of quantitation were 0.3, 1.0 μg/L. When the addition concentrations were 50.0, 150.0 and 450.0 μg/L, the recovery rates were 92.8%-94.6% , the intra assay precisions were 3.6%-5.7% , and the inter assay precisions were 3.4%-5.4%. The linear range of TTCA was 0.1-200.0 μg/L, the linear equation was y=1164.7x-2243.9, and the correlation coefficient was 0.9991. The detection limit and the limit of quantitation were 0.03, 0.1 μg/L. When the addition concentrations were 10.0, 40.0 and 160.0 μg/L, the recovery rates were 90.8%-93.6%, the intra assay precisions were 4.6%-7.4%, and the inter assay precisions were 4.4%-6.9%. Conclusion: The sample pretreatment process of the ultra high performance liquid chromatography tandem mass spectrometry method for the determination of Cre and TTCA in urine is simple, and the continuous determination of Cre and TTCA in urine can be realized only by switching mass spectrometry parameters under the same chromatographic conditions, which is accurate and efficient, and each performance index of the method meets the determination requirements.
Chromatography, High Pressure Liquid ; Creatinine ; Humans ; Tandem Mass Spectrometry ; Thiazolidines

Objective:To study the soil physical and chemical properties， microorganisms， and metabolites in different culture environments of Gastrodia elata， so as to provide scientific basis for subsequent cultivation of G. elata in multiple environments. Method:The tubersphere soil of G. elata cultured in different environments was collected for analyzing the soil nutrients， microbial numbers， and metabolite differences using the agrochemical method， plate-count method， and gas chromatography-time-of-flight mass spectrometry （GC-TOF-MS）-based non-targeted metabonomic approach. Result:The analysis of soil physical and chemical properties revealed the highest soil moisture， pH， available potassium， and available phosphorus in the spinney and the highest electrical conductivity， total nitrogen， alkali-hydrolyzable nitrogen， and organic matter in the pinewood. As demonstrated by the quantitative analysis of soil microorganisms， the cultivable microorganisms were bacteria， actinomycetes， and fungi， with the bacterial population and total microbial biomass in the spinney and the number of fungi and actinomycetes in the barren slope detected to be the largest. The ratio of bacteria to fungi （B/F value） in the pinewood was the highest， while that in the barren slope was the lowest. The results of metabonomic research demonstrated that the compositions and quantities of soil metabolites in the spinney （Z group）， pinewood （S group）， and barren slope （HD group） varied. Through comparisons between S and Z groups， between HD and Z groups， as well as between HD and S groups by orthogonal partial least squares discriminant analysis （OPLS-DA）， 18， 35， and 24 differential metabolites were separately screened out， and the Kyoto Encyclopedia of Genes and Genomes （KEGG） pathway enrichment analysis yielded 5， 9， and 13 metabolic pathways. There existed a significant causal relationship of the soil physical and chemical properties and microbial numbers with the metabolites. Conclusion:The soil physical and chemical properties， microbial numbers， and metabolite changes differed significantly in different culture environments of G. elata， which were sorted by the suitability in a descending order as follows： spinney > pinewood >barren slope. The soil physical and chemical properties and microbial numbers are the crucial factors driving changes in soil metabolites， suggesting that regulating the soil physical and chemical characteristics and microbial characteristics in the culture environment is an important mechanism for maintaining the G. elata-soil-microbial symbiotic system.

Based on the theory of "component structure", the component structure characteristics of 17 inorganic elements in 20 batches of genuine Moutan Cortex and 12 batches of non-genuine Moutan Cortex were analyzed. The analytical method of inductively coupled plasma mass spectrometry(ICP-MS) for inorganic elements in Moutan Cortex was established, and the fingerprint of inorganic elements was drawn. Through correlation analysis and principal component analysis, the constituent elements of inorganic elements in Moutan Cortex were excavated, namely characteristic elements As, Cr, Pb, Se, K, Cu and Cd. The amount and the quantity relative ratio between the components of genuine and non-genuine Moutan Cortex samples were analyzed. It was found that the amount of characteristic elements in the bulk genuine Moutan Cortex samples was 0.33, 1.42, 1.33, 0.11, 4 385.78, 4.87, 0.49 mg·kg~(-1), with the quantity relative ratio of 1.00∶4.30∶4.03∶0.33∶13 290.24∶14.76∶1.48. The amount of characteristic elements in sub-packaged genuine Moutan Cortex was 0.24, 1.96, 0.36, 0.05, 5 122.01, 4.81, 0.05 mg·kg~(-1), with the quantity relative ratio of 1.00∶8.17∶1.50∶0.21∶21 341.71∶20.04∶0.21. The unique structural characteristics of inorganic elements in genuine Moutan Cortex are studied to provide a basis for the quality control and safety evaluation of Moutan Cortex.
Drugs, Chinese Herbal ; Paeonia ; Principal Component Analysis ; Quality Control ; Trace Elements

Guided by the theory of "component structure", we analyzed the structural characteristics of pharmacodynamical components in genuine Moutan Cortex. The compositions of organic small molecules were determined by high performance liquid chromatography(HPLC) for 20 batches of genuine Moutan Cortex and 12 batches of non-genuine Moutan Cortex. By means of similarity analysis, clustering analysis(CA), principal component analysis(PCA) and orthogonal partial least-squares discriminant analysis(OPLS-DA), the elements in structural characteristics of the pharmacodynamical components were extracted as follows: terpene glycosides components(oxidized paeoniflorin, paeoniflorin,galloyl paeoniflorin, benzoyloxy paeoniflorinand benzoyl paeoniflorin), tannin components(1,3,6-tri-O-galloside acyl glucose, pentagalloyl glucose), and phenolic acid components(methyl gallate, paeonol). The contents and quantity ratios of terpene glycoside component, tannin component and phenolic acid components in genuine Moutan Cortex were determined as 14.1, 12.5, 21.7 mg·g~(-1), 1.00∶0.89∶1.54. The contents and quantity ratios of the oxidized paeoniflorin, paeoniflorin and benzoylpaeoniflorin in the terpene glycoside components were characteristic and determined as 2.05, 7.05, 3.30 mg·g~(-1), 1.00∶3.44∶1.61. The unique structural characteristics of genuine Moutan Cortex provide scientific basis for the formulation of quality standards.
Chromatography, High Pressure Liquid ; Drugs, Chinese Herbal ; Paeonia ; Principal Component Analysis

Traditional Chinese medicine is the product of clinical medication practice of the Chinese nation for thousands of years. Its material basis is the key to reveal the essence of the roles of traditional Chinese medicine, and the fundamental guarantee to solve the difficulties in the quality control of traditional Chinese medicine. However, the material basis of traditional Chinese medicine is to exert the overall pharmacodynamic effect through multi-targets, multi-approaches and mutual cooperation, resulting in unclear quality control index. In recent years, the quality control standards of traditional Chinese medicine have experienced great changes by shifting the focus from the appearance characteristics to the internal material basis, which however is limited to the control of a single com-ponent or multiple components. In other words, the intrinsic effectiveness and safety could not be guaranteed without the characteristics of the integrity of traditional Chinese medicine. With Moutan Cortex as an example, this paper analyzed the evolution of Moutan Cortex quality standards based on Chinese Pharmacopoeia, and comprehensively summarized the material basis of Moutan Cortex. Based on the theory of "component structure", this study analyzed current quality control of the material basis of Moutan Cortex and its preparations, and expounded the development trend of multi-dimensional quality control, so as to lay a foundation for establishing a more rational quality control system for traditional Chinese medicine in the future.
Drugs, Chinese Herbal ; Medicine, Chinese Traditional ; Paeonia ; Quality Control

Anticoagulants ; Humans ; Pulmonary Embolism/diagnosis* ; Recurrence ; Risk Factors ; Venous Thromboembolism