Endotoxins are common exogenous pyrogens. Excessive endotoxins in medical devices and injections can lead to serious consequences such as sepsis, septic shock, and even death. Therefore, endotoxin detection plays a crucial role in medical, pharmaceutical, and food sectors. The wide application of Limulus amebocyte lysate (LAL) has led to a sharp decline in the number of horseshoe crabs. Moreover, the LAL assay has limitations such as interbatch variations and difficulty in quantification. The recombinant factor C (rFC) assay is stable between batches, highly sensitive, and capable of quantitation, and thus it can be used as an alternative for the LAL assay. However, the high cost and complex procedures involved in producing recombinant factor C have limited the widespread application of this method. In order to simplify the preparation and reduce the production cost of recombinant factor C, this study focuses on the production of recombinant factor C based on the baculovirus expression system. Multiple measures such as a high-yield and anti-apoptotic vector qBac-IIIG, the optimal signal peptide, and the optimized codon were used to reach the goal of endotoxin detection with cell supernatant. This method simplifies the steps of protein purification. The sensitivity of the supernatant reached 0.05 EU/mL in a 1-L fermentation system, and 500 000 detecting reactions can be supported per liter of fermentation broth. This study increases the yield and activity of recombinant factor C, simplifies the procedures of protein purification, and reduces the cost, laying a foundation for the promotion and application of recombinant factor C in endotoxin detection.
Animals ; Recombinant Proteins/genetics* ; Horseshoe Crabs/chemistry* ; Baculoviridae/metabolism* ; Endotoxins/analysis* ; Protein C/biosynthesis* ; Genetic Vectors/genetics* ; Arthropod Proteins/genetics* ; Enzyme Precursors ; Serine Endopeptidases

【Objective】 To investigate the effect of Qingkailing injection on platelet function preserved in vitro. 【Methods】 A total of 15 bags of plateletpheresis (≥250 mL/bag), adding Qingkailing injection(1.25 mL/bag) at the final concentration of 1%, were stored at 22 ℃ with gentle agitation as the experimental group, and samples were collected on day 1, 3, 5, 8, 10 and 14 to detect the thromboelastogram (TEG), CD62p expression rate and mitochondrial membrane potential (JC-1). The control group was set up synchronously, with the same volume and storage conditions as the experimental groups, and samples were taken on day 1, 3 and 5 after preservation to undertake the same test items as the experimental groups. The differences of detection indexes between the two groups were compared. 【Results】 1) In the experimental group, there was no significant change in K and α during day 1 to 14(P>0.05). The R value (min) increased from 6.12±1.58 to 11.02±2.26, and the CI value changed from 0.27±1.24 to -10.47±3.51 (P<0.05). The MA value (mm) had no significant change within 5 days (P>0.05), but decreased to 53.18±2.71 on day 8 and 22.88±3.45 on day 14 (P<0.05). In the control group during day 1 to 5, K(min) and α showed no significant change, while R(min) was significantly prolonged, MA (mm) decreased and CI increased significantly (P<0.05). 2) The expression rate of CD62p (%) was 70.50±9.12 in the experimental group on day 5 (vs 83.16±5.33 in the control groups, P<0.05) and 82.77±7.17 on day 14 (P<0.05). 3) There was no significant change in JC-1 (%) during regular preservation period between the experimental group and control group (P>0.05), but JC-1 (%) was 86.75±3.88 vs 70.36±19.8 on day 5 (P<0.05). In the experimental group, JC-1(%) was 81.04±9.50 vs 71.38±8.77 vs 82.77±7.17 on day 8, 10 and 14, respectively. 【Conclusion】 The activation and aggregation as well as anti-apoptosis function of plateletpheresis, adding Qingkailing injection at the final concentration of 1%, are similar to those of routine preservation.

Objective:To investigate the roles of S100B protein and anti-brain antibody (ABAb) in the pathophysiology of Alzheimer's disease (AD) by analyzing the changes of the serum levels of S100B and ABAb and the relationships of the measures with cognition deficits in patients with AD.Methods:In this study,32 patients with AD(AD group) and 40 age-matched volunteers without cognitive impairment(control group) were enrolled.The diagnosis was made according to the Diagnostic and Statistical Manual of Mental Disorders,Fourth Edition (DSM-Ⅳ).The mental and social functional conditions were assessed with the Mini-Mental State Examination (MMSE) and Activity of Daily Living Scale(ADL),the cognitive function of patients was evaluated with the Alzheimer's Disease Assessment Scale-cognitive subscale(ADAS-Cog).The serum S100B proteinand ABAb levels were examined by enzyme-linked immuno sorbent assay(ELISA).Results:The serum S100B protein[(0.66 ± 0.17) μg/L vs.(0.30 ± 0.04)μg/L] and ABAb [(1.93 ± 0.95) U/L vs.(1.31 ± 0.25) U/L] levels were higher in AD patients than in the controls (Ps ＜ 0.01).In AD patients,the serum S 100B protein markedly negatively correlated with the scores of the MMSE(r =-0.66),while positively correlated with ADL and ADAS-Cog(r =0.57,r =0.53)(Ps ＜ 0.005).ABAb levels negatively correlated with the scores of the MMSE(r =-0.57),while positively correlated with ADL and ADAS-Cog(r =0.52,r =0.34)(Ps ＜0.05).The serum S100B protein levels were positively related to ABAb levels in AD group(r =0.51.P ＜0.005),but not in control group(r =0.076,P =0.654).Conclusions:It suggests that the serum levels of S100B protein and ABAb are related with cognitive function in patients with Alzheimer's disease,and S100B protein and ABAb might play key roles in mechanism of Alzheimer's disease.

Objective To examine the prospective associations between airflow obstruction (AFO) and risks of major chronic diseases morbidity in Chinese adults.Methods Samples of this study were from the China Kadoorie Biobank.A total of 486 996 participants aged 30 to 79 years (mean 51.5 years) at the baseline study,were included after excluding those who self-reported of having heart disease,stroke and cancer at baseline.AFO was defined under the Global Initiative on Obstructive Lung Disease (GOLD) criteria and forced expiratory volume per one second in percentage of the expected one (FEV1％P).Cox regression models were used to investigate the associations of AFO with incidence rates of ischemic heart disease,cerebrovascular disease and lung cancer after adjusted for potential confounders.Results Over a period of 7 years through the follow-up program,the incident cases of ischemic heart disease,cerebrovascular disease and lung cancer appeared as 24 644,36 336 and 3 218,respectively.Compared with people without AFO,the HR (95％CI) of GOLD-1 to GOLD-4 were 0.89 (0.78-1.01),1.05 (0.98-1.12),1.29 (1.18-1.40) and 1.65 (1.42-1.91) respectively for ischemic heart disease.The HR (95％ CI) of GOLD-1 to GOLD-4 were 0.96 (0.70-1.26),1.12 (0.96-1.31),1.38 (1.14-1.65) and 1.48 (1.05-2.02) respectively for lung cancer.No statistically significant differences in the associations between GOLD level and cerebrovascular disease morbidity were found.However,each 10％ decrease in FEV1％P was associated with 7.2％ (95％CI:6.4％-8.0％),3.6％ (95％CI:3.0％-4.3％) and 10.5％ (95％CI:8.4％-12.6％) increased the risks of ischemic heart disease,cerebrovascular disease and lung cancer respectively.The results were persistant when stratified by smoking status.Conclusion Higher degree of AFO seemed to be associated with the risks of ischemic heart disease,cerebrovascular disease and lung cancer morbidity among the Chinese adults.

OBJECTIVETo reveal chemical diversify of volatile oils in Houttuynia cordata from major producing areas in China and their genetic basis, lay a foundation for breeding a quality H. cordata variety.

METHODThe volatile oils in H. cordata from 22 provenances were determined by GC. And the relationship among the peak areas of volatile oils, biological characteristics and RAPD makers were analyzed.

RESULTThere were common and special volatile oils in H. cordata from different provenances. The peak areas of common volatile oils in samples were significantly different. The clustering figure based on the peak areas or the relative peak areas of common volatile oils was almost agreed with the one based on RAPD makers analysis. And the differences in chromatograms could be distinguished according to the biological characteristics.

CONCLUSIONThe diversity of volatile oils exists in H. cordata from different provenances which relate with biological characteristics and has genetic basis. H. cordata can be divided into 2 types according to volatile oils, biological characteristics or RAPD marker.

Chromatography, Gas ; Genetic Markers ; Houttuynia ; anatomy & histology ; chemistry ; genetics ; Oils, Volatile ; chemistry ; Phylogeny ; Random Amplified Polymorphic DNA Technique