ABSTRACT
This study aims to construct a dynamic two-dimensional characterization technique for the hygroscopicity of traditional Chinese medicine extracts and investigate the effect of material properties of powders on hygroscopicity. The dynamic hygroscopicity-time curves of the powders were measured at 25 ℃ and 75% humidity, and the semi-equilibrium hygroscopicity time (t1/2) and equilibrium hygroscopicity (F∞) were derived as two-dimensional evaluation indicators. Finally, the correlation between the material properties and the hygroscopic behavior was analyzed by principal component analysis (PCA) and partial least squares analysis (PLS). The results showed that the dynamic two-dimensional characterization system of hygroscopicity constructed with 1/t1/2 = 0.1 h-1 and F∞ = 15% as the center can classify the hygroscopic behavior of traditional Chinese medicine extracts into four categories: fast hygroscopicity with strong hygroscopicity, slow hygroscopicity with strong hygroscopicity, fast hygroscopicity with weak hygroscopicity and slow hygroscopicity with weak hygroscopicity. The moisture absorption was negatively correlated with D50, D90, ρb and ρt; the moisture absorption rate was negatively correlated with D10, D50, D90, ρb, ρt, and positively correlated with moisture content. The hygroscopicity dynamic two-dimensional characterization indicators of Chinese medicine extracts (CMEs) constructed in this study matched with the physical properties. The method of dynamic multi-dimensional characterization technology is feasible and scientific, and the idea has strong promotional value.
ABSTRACT
At present, the modernization of Chinese medicine preparations (CMPs) is still a challenging task. The 3 typical Chinese medicine materials (CMMs) used for preparing CMPs are the powders, extracts, and components of Chinese medicine and their properties of CMMs are important for designing CMPs. Basing on our long term research, we have established a property system for CMMs according to the state of CMMs under an exactly condition and according to the interaction characteristics between substances. The property system could be divided into 5 categories: material composition, spatial structure, body property, surface property, physicochemical properties, and they could also be divided into 18 subcategories. Furthermore, we also established the corresponding index and characterization system, where the 61 indexes and characterization techniques were systematically summarized. At last, we hope that the article will promote the modernization of CMPs.
ABSTRACT
This study was designed to investigate the correlations of the spatial structure properties of Chinese medicinal extracts with hygroscopicity and the anti-hygroscopic techniques. With Poria extract used as the model drug, pregelatinised starch and microcrystalline cellulose at different ratios were added into Poria fluid extract for preparing powder particles with diverse spatial structures using different drying processes. Then, their hygroscopic behaviours were characterized by equilibrium hygroscopicity(F~∞) and semi-hygroscopic time(t_(1/2)). The correlations of the hygroscopicity of each powder with the spatial structure properties such as particle size(D_(90)), porosity(ε), true density(ρ_t), and surface element distribution were analyzed using partial least-squares method. The F~∞ and t_(1/2) values of Poria extract prepared by three drying methods were sorted in a descending order as follows: F~∞(spray drying>drying at ordinary pressure>drying at reduced pressure); t_(1/2)(drying at reduced pressure>drying at ordinary pressure>spray drying). The powder obtained by spray drying showed a spherical structure with the smallest particle size and intra-particle ε but relatively stronger hygroscopicity. The large-scale surface element enrichment of the powders dried by reduced pressure effectively reduced their hygroscopicity. F~∞ and t_(1/2) were negatively correlated with ε but positively with D_(90), and the interactive influence of each spatial structural properties was not significant. There existed a correlation between the spatial structure of the powder particles of Chinese medicine extracts and their hygroscopicity, and the hygroscopicity could be improved by designing the spatial structure. This study has provided some practical basis for developing the moisture-proof technology of Chinese medicinal preparations.
Subject(s)
China , Particle Size , Plant Extracts , Powders , Technology , WettabilityABSTRACT
Objective To investigate the distribution and antimicrobial resistance of pathogens isolated from blood specimen,and provide laboratory basis for clinical treatment of bloodstream infection. Methods Pathogens isolated from blood specimen in a hospital laboratory from January 1,2015 to December 31,2016 were identified and per-formed antimicrobial susceptibility testing.Results A total of 1 061 pathogenic strains were isolated from blood speci-men,of which gram-negative bacillus,gram-positive coccus,and fungus accounted for 53.35%(n= 566),36.10%(n=383),and 10.55%(n= 112)respectively,the major gram-negative bacillus,gram-positive coccus,and fungus were Escherichia coli(E.coli)and Klebsiella pneumoniae(K.pneumoniae),coagulase-negative Staphylococcus,and Candida parapsilosis respectively. Strains were mainly isolated from intensive care unit(ICU,n= 308,29.03%),followed by hematology department and pediatric internal medicine department. Resistance rates of E.coli and K. pneumoniae to imipenem were 2.65% and 40.12% respectively.Extended-spectrum beta-lactamase(ESBL)-produ-cing E.coli and K.pneumoniae accounted for 62.96% and 33.14% respectively. Linezolid- and vancomycmin-re-sistant Staphylococcusspp. Were not found,isolation rates of methicillin-resistant coagulase-negative Staphylococ-cus and methicillin-resistant Staphylococcus aureus were 83.61% and 45.45% respectively,one vancomycin-resis-tant Enterococcus faeciu m and one linezolid-resistant Enterococcus faecium were isolated respectively.Conclusion There are multiple species of pathogens isolated from blood specimen,distribution and antimicrobial resistance of pathogens casing bloodstream infection should be monitored regularly to guide the empiric antimicrobial therapy.
ABSTRACT
Objective To evaluate the influence of menopause status on breast fibrograndular tissue (FGT),background parenchymal enhancement volume ratio (BPEv) and intensity ratio (BPEI) by breast MR image automatic quantitative analysis.Methods From 14 033 consecutive patients who underwent breast MR in our center from 2009 to 2012,we randomly selected 101 normal cases (47cases of premenopausal and 54 cases of postmenopausal).Premenopausal status was subclassified into four groups (8 cases in the 1st week and 13 cases in the 2nd,3rd and 4th week,respectively) based on the menstrual cycle.We evaluated FGT,BPEv and BPEI at early (2 minutes),medium (4 minutes) and late (6 minutes) enhanced time phases of breast MRI for quantitative assessment.The FGT,BPEv and BPEI in premenopausal and postmenopausal women were compared using the Mann-Whitney U test.Comparison of each menstrual cycle was made using the Kruskal-Wallis test.Results The FGT,BPEv and middle-late BPEI of postmenopausal women were significantly lower than that of premenopausal women (P＜0.05).The maximum BPEI was in the 1st week,the minimum in the 2nd week in premenopausal women (P＜0.05).The FGT and BPEv in the 1st week were the highest among the 4 weeks,but there was no significant difference.Conclusions The FGT,BPEv and BPEI were significantly decreased after menopause.The optimal time of breast MR examination is in the 2nd week of menstrual cycle.