Antimicrobial resistance and plasmid-mediated colistin resistance mechanism of diarrheagenic Escherichia coli recovered from foods in parts of China in 2020 / 中华预防医学杂志

Objective: To investigate the antimicrobial resistance of food-borne diarrheagenic Escherichia coli (DEC) and the prevalence of mcr genes that mediates mobile colistin resistance in parts of China, 2020. Methods: For 91 DEC isolates recovered from food sources collected from Fujian province, Hebei province, Inner Mongolia Autonomous Region and Shanghai city in 2020, Vitek2 Compact biochemical identification and antimicrobial susceptibility testing platform was used for the detection of antimicrobial susceptibility testing (AST) against to 18 kinds of antimicrobial compounds belonging to 9 categories, and multi-polymerase chain reaction (mPCR) was used to detect the mcr-1-mcr-9 genes, then a further AST, whole genome sequencing (WGS) and bioinformatics analysis were platformed for these DEC isolates which were PCR positive for mcr genes. Results: Seventy in 91 isolates showed different antimicrobial resistance levels to the drugs tested with a resistance rate of 76.92%. The isolates showed the highest antimicrobial resistance rates to ampicillin (69.23%, 63/91) and trimethoprim-sulfamethoxazole (59.34%, 54/91), respectively. The multiple drug-resistant rate was 47.25% (43/91). Two mcr-1 gene and ESBL (extended-spectrum beta-lactamase) positive EAEC (enteroaggregative Escherichia coli) strains were detected. One of them was identified as serotype of O11:H6, which showed a resistance profile to 25 tested drugs referring to 10 classes, and 38 drug resistance genes were predicted by genome analysis. The other one was O16:H48 serotype, which was resistant to 21 tested drugs belonging to 7 classes and carried a new variant of mcr-1 gene (mcr-1.35). Conclusion: An overall high-level antimicrobial resistance was found among foodborne DEC isolates recovered from parts of China in 2020, and so was the MDR (multi-drug resistance) condition. MDR strains carrying multiple resistance genes such as mcr-1 gene were detected, and a new variant of mcr-1 gene was also found. It is necessary to continue with a dynamic monitoring on DEC contamination and an ongoing research into antimicrobial resistance mechanisms.

Polysaccharide of Balanophora involucrata Hook. f. attenuates cell ferroptosis in rats with experimental liver injury through SLC7A11/GPX4 pathway / 药学学报

Polysaccharide of Balanophora involucrata Hook. f. (BPS), the major component of Balanophora involucrata Hook. f., was confirmed the protective effect on liver injury in our previous study. This research aimed to investigate the protective mechanism of BPS on experimental liver injury by attenuating cell ferroptosis through modulating solute carrier family 7 member 11/glutathione peroxidase 4 (SLC7A11/GPX4) pathway. The animal experiment was approved by the Experimental Animal Ethical Committee of Hubei Minzu University and all rats had received human care in compliance with the institutional animal care guidelines. Rats were given intraperitoneal injection of (D-galactosamine, D-GalN) solution (800 mg·kg-1) one time to establish the acute liver injury model. The results showed aspartate amino transferase (AST), alanine aminotransferase (ALT) and 4-hydroxynonenal (4-HNE) levels in serum were decreased, and the contents of reactive oxygen species (ROS), Fe2+, malondialdehyde (MDA) and lipid peroxide (LPO) in liver tissues also decreased and glutathione (GSH) level increased after BPS administration with 200 mg·kg-1. Besides, BPS reduced iron deposition and increased the expression of SLC7A11 and GPX4 proteins in liver tissue. In conclusion, BPS ameliorated experimental liver injury by alleviating cell ferroptosis through SLC7A11/GPX4 pathway. The present study pointed to the possibility of utilizing BPS for protection against liver injury in clinic.

Research progress and prospects for the use of plant metabolomics in quality evaluation of traditional Chinese medicinal materials / 药学学报

The quality of traditional Chinese medicine has a direct impact on the effectiveness and safety of its use, and is the premise necessary to ensure the healthy development of the traditional Chinese medicine industry. Comprehensive and accurate control and evaluation of the quality of medicinal materials is of great significance to the traditional Chinese medicine industry, but the complexity and dynamics of the chemical composition of medicinal materials makes their quality evaluation a challenge. Plant metabolomics provides an integrated and comprehensive analysis that is consistent with the holistic approach of traditional Chinese medicine. Chemical information therein promotes the establishment of a traceable system and provides new ideas and methods for the quality evaluation of medicinal materials. Plant metabolomics in the quality evaluation of medicinal materials is gradually increasing, and the core is the screening and identification of differential metabolites or specific marker compounds by means of stoichiometry. This study focused on the main factors that affect the quality of medicinal materials, such as origin, environmental adversity, varieties, harvest time, commercial specification and TCM processing. We describe the research progress in plant metabolomics combined with chemometrics analysis for the quality control and evaluation of medicinal materials, summarize existing problems, identify trends, and propose future research directions. Metabolomics plays an increasingly important role in the quality evaluation of medicinal materials, but the absolute qualitative and quantitative information of metabolomics needs to be further developed, and a single 'omics' technique is not sufficient for an in-depth analysis of medicinal value. In the future, standardization of plant metabolomics methods and a more complete database should be actively promoted, and plant metabolomics should be integrated into quality marker exploration. Plant metabolomics will need to be integrated with other 'omics' methods to improve the quality and evaluation system of medicinal materials.

Isolation and Structural Elucidation of Chemical Constituents of Corydalis Rhizoma / 中国实验方剂学杂志

Objective: In order to clarify the characteristic chemical constituents and furnish applicable information to the basic research and quality control research related to the chemistry of traditional Chinese medicines for Corydalis Rhizoma,this paper investigated the chemical constituents of Corydalis Rhizoma extensively. Method: The dried-up and pulverized plant materials were extracted using 95% EtOH as solvent,the EtOH extract was fractionated using different solvents to afford the EtOAc-soluble and n-BuOH-soluble portion,respectively,among others. These two portions were subjected to procedures of isolation and purification on silica gel or ODS column chromatographies to afford monomers. 1D and 2D NMR and MS methods,along with comparison with the data of literatures,were used to identify the structures. Result: Twelve compounds,all belonging to alkaloids,were isolated and identified as d-corydaline(1),tetrahydrocoptisine(2),tetrahydropalmatine(3),tetrahydrocolumbamine(4),corybulbine(5),tetrahydrojatrorrhizine(6),dehydrocorydaline(7),dehydroglaucine(8),8-oxodihydrocoptisine(9),protopine(10),taxilamine(11),and pontevedrine(12). Of these compounds,the structure of 12 was a revised structure which was assigned by combined examinations of their 1D and 2D NMR spectra and MS data. Conclusion: Compounds 6 and 11 were reported from Corydalis Rhizoma for the first time. The structure of pontevedrine was verified as 1,2,9,10-tetramethoxy-6-methyl-4H-dibenzo[de,g]quinoline-4,5(6H)-dione.

Development and application of portable hanging perfusion support / 医疗卫生装备

Objective To develop a portable hanging perfusion support used in the medical tent of field medical unit.Methods The support was composed of a support body,a hanging hook at one end of the body,hanging components and an automatic locking mechanism.The hanging components included two screw hangers and two inverted cone-shaped sleeves.The support body consisted of three stainless steel tubes with different sizes,whose height could be regulated through connecting thread to adapt the support to hanging the dropping bottle.Results The support gained advantages over the traditional one in convenience as well as deployment and withdrawal time,and enhanced medical training efficacy and casualty treatment timeliness greatly.Conclusion The support behaves well in structure,operation and portability,and can be used for patient treatment in battlefield,disaster relief and etc.

Improved design and application of central oxygen supply system in treatment group of field medical unit / 医疗卫生装备

Objection To improve the central oxygen supply system at field conditions to realize rapid transport of oxygen cylinders and enhanced application of medical oxygen.Methods The modified central oxygen supply system was composed of the 40-L oxygen cylinder,triple ball valve,flowmeter,dichotomantheshos hose,disposable nasal catheter for oxygen inhalation,pressure relief valve,immovable hanger and L-shaped trolley for oxygen cylinder.The trolley was composed of a bearing frame designed according to the size of oxygen cylinder,a fixing band and two wheels,which could be used for efficient fixation and rapid transport of oxygen cylinder.Results The improved system met the requirements for materials storage,loading,deployment and withdrawal during oxygen supply,and saved manpower and space.Conclusion The improved system enhances the efficiency of medical oxygen application and the supportability of field medical unit,and thus is worthy promoting in mobile medical unit.

Molecular and Epidemiological Characterization of Infant Botulism in Beijing, China / 生物医学与环境科学（英文）

Laboratory-based pathogen isolation, identification, and toxicity determination were performed on samples from a suspected case of infant botulism. Mice injected with cultures generated from the enema sample and ingested Powered infant formula (PIF) presented typical signs of botulism. Antitoxins to polyvalent botulinum neurotoxins (BoNTs) and monovalent BoNT type B antitoxin had protective effects. Clostridium botulinum isolated from the enema and residual PIF samples were positive for type B toxin. Pulsed-field gel electrophoresis (PFGE) revealed that the two strains of C. botulinum isolated from the two samples produced indistinguishable pulsotypes. These findings confirmed this case of type B infant botulism associated with the ingestion of PIF contaminated by type B C. botulinum spores.

Genotypic Characterization of Methicillin-resistant Staphylococcus aureus Isolated from Pigs and Retail Foods in China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the genotypic diversity of Methicillin-resistant Staphylococcus aureus (MRSA) isolated from pigs and retail foods from different geographical areas in China and further to study the routes and rates of transmission of this pathogen from animals to food.</p><p><b>METHODS</b>Seventy-one MRSA isolates were obtained from pigs and retail foods and then characterized by multi-locus sequencing typing (MLST), spa typing, multiple-locus variable number of tandem repeat analysis (MLVA), pulsed-field gel electrophoresis (PFGE), and antimicrobial susceptibility testing.</p><p><b>RESULTS</b>All isolated MRSA exhibited multi-drug resistance (MDR). Greater diversity was found in food-associated MRSA (7 STs, 8 spa types, and 10 MLVA patterns) compared to pig-associated MRSA (3 STs, 1 spa type, and 6 MLVA patterns). PFGE patterns were more diverse for pig-associated MRSA than those of food-associated isolates (40 vs. 11 pulse types). Among the pig-associated isolates, CC9-ST9-t899-MC2236 was the most prevalent clone (96.4%), and CC9-ST9-t437-MC621 (20.0%) was the predominant clone among the food-associated isolates. The CC9-ST9 isolates showed significantly higher antimicrobial resistance than other clones. Interestingly, CC398-ST398-t034 clone was identified from both pig- and food-associated isolates. Of note, some community- and hospital-associated MRSA strains (t030, t172, t1244, and t4549) were also identified as food-associated isolates.</p><p><b>CONCLUSION</b>CC9-ST9-t899-MC2236-MDR was the most predominant clone in pigs, but significant genetic diversity was observed in food-associated MRSA. Our results demonstrate the great need for improved surveillance of MRSA in livestock and food and effective prevention strategies to limit MDR-MRSA infections in China.</p>

Antimicrobial Resistance, Virulence Profile, and Molecular Characterization of Listeria monocytogenes Isolated from Ready-to-eat Food in China, 2013-2014 / 生物医学与环境科学（英文）

We aimed to investigate the potential pathogenic profile and antibiotic resistance of Listeria monocytogenes isolated from ready-to-eat food in China. Antimicrobial resistance was determined by broth microdilution following the Clinical and Laboratory Standards Institute protocol. Molecular serotyping, virulence, and resistance genes were identified using PCR. Multi-locus sequence typing was performed on resistant strains. A total of 11.53% (113/980) isolates were resistant, from which 82.3% (93/113) harbored all the virulence genes tested. The resistant strains were subtyped into 18 sequence types (STs), from which ST2, ST5, ST8, and ST9 were involved in listeriosis. This study indicated that several L. monocytogenes isolates from ready-to-eat foods in China have pathogenic potential and are resistant to antibiotics, including antibiotics used as medicines by humans for listeriosis treatment.

Relationship between Intrauterine Bacterial Infection and Early Embryonic Developmental Arrest / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Early embryonic developmental arrest is the most commonly understudied adverse outcome of pregnancy. The relevance of intrauterine infection to spontaneous embryonic death is rarely studied and remains unclear. This study aimed to investigate the relationship between intrauterine bacterial infection and early embryonic developmental arrest.</p><p><b>METHODS</b>Embryonic chorion tissue and uterine swabs for bacterial detection were obtained from 33 patients who underwent artificial abortion (control group) and from 45 patients who displayed early embryonic developmental arrest (trial group).</p><p><b>RESULTS</b>Intrauterine bacterial infection was discovered in both groups. The infection rate was 24.44% (11/45) in the early embryonic developmental arrest group and 9.09% (3/33) in the artificial abortion group. Classification analysis revealed that the highest detection rate for Micrococcus luteus in the early embryonic developmental arrest group was 13.33% (6/45), and none was detected in the artificial abortion group. M. luteus infection was significantly different between the groups (P < 0.05 as shown by Fisher's exact test). In addition, no correlation was found between intrauterine bacterial infection and history of early embryonic developmental arrest.</p><p><b>CONCLUSIONS</b>M. luteus infection is related to early embryonic developmental arrest and might be one of its causative factors.</p>

Modification and evaluation of Brucella broth based Campylobacter jejuni transport medium / 生物医学与环境科学（英文）

Reliable transport of Campylobacter jejuni isolates is critical to microbial epidemiology research, especially in developing countries without a good temperature control mailing system. Various factors, including oxygen, temperature, transport medium composition, could affect the survival of C. jejuni. In this study, the protective effects of different ingredients in C. jejuni transport media at 4 °C and 25 °C and under aerobic condition were quantitatively evaluated respectively. The results showed that enriched medium, supplementation with 5% blood and being kept at 4 °C could improve the viability of different C. jejuni strains during transport. In addition, supplementation with 25 mmol/L L-fucose in Wang's transport medium could significantly improve the survival of C. jejuni at both 4 °C and 25 °C. To the best of our knowledge, this is the first report to evaluate the protective effect of L-fucose in enriched C. jejuni transport medium which is feasible in developing countries without an effective cold chain mailing system. These data will be good reference for C. jejuni transport medium improvement in future.

Characterization of Staphylococcus aureus isolated from clinical specimens by matrix assisted laser desorption/ionization time-of-flight mass spectrometry / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To develop a matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) approach to identify Staphylococcus aureus (S. aureus) and differentiate methicillin-resistant S. aureus (MRSA) from methicillin-sensitive S. aureus (MSSA).</p><p><b>METHODS</b>A total of 100 S. aureus strains isolated from clinical specimens and farm workers were collected and analyzed by MALDI-TOF-MS. And data obtained were interpreted with biotyper software.</p><p><b>RESULTS</b>Ninety-two strains were identified by MALDI-TOF-MS as S. aureus at a level of secure genus and probable species, and 4 strains were identified at probable genus after their cultivation, spectral collection and data preprocessing. One strain was identified as S. aureus with lower score. It was revealed that identification of S. aureus by MALDI-TOF-MS was highly correlated with typing by biochemical and serological methods with an accuracy as high as 97%. The biotyper cluster analysis showed that 100 isolates were divided into 2 types at the distance level of 400. Higher peak intensity in the mass of both 3784 Da and 5700 Da was observed in MRSA, whereas that was absent from MSSA.</p><p><b>CONCLUSION</b>MALDI-TOF-MS is considered a simple, rapid and highly reproducible technique with high-throughput and accuracy for the identification of S. aureus and it can reliably differentiate MRSA from MSSA.</p>

Development of an in vitro digestion model for assessing the bioaccessibility of aflatoxin B group in foods / 中华预防医学杂志

<p><b>OBJECTIVE</b>To develop and validate an in vitro digestion model for assessing the bioaccessibilities of some important mycotoxins of aflatoxin B group (aflatoxin B(1) and aflatoxin B(2), AFB(1) and AFB(2)).</p><p><b>METHODS</b>Using simulating gastrointestinal physiological digestion process, the effects of digestion time (long, medium and short), the fasting and feeding status (fasting, between fasting and semi-feeding, semi-feeding, between semi-feeding and feeding, feeding states), the volume and pH (high, medium and low) of digestive solution, as well as other food ingredients ingested along with aflatoxin B group from mixed foods on bioaccessiblities of AFB(1) and AFB(2) in the mouth, stomach and small intestine were studied. The optimal technical parameters of the model were identified and the model was validated with mycotoxin adsorbents.</p><p><b>RESULTS</b>The optimal conditions of AFB(1) releasing from the ingested foods at the highest concentration in gastrointestinal tract were as follows: digestion time of 6 min, 1.5 h and 2.5 h in mouth, stomach and duodenum, respectively; the optimal pH values of 1.1 and 7.5 for gastric juice and duodenal fluid; the volume of 7, 13, 12 and 6 ml for saliva, gastric juice, intestinal fluid and bile, respectively; the optimal conditions of AFB(2) releasing from the ingested foods at the highest concentration in gastrointestinal tract were as follows: digestion time of 6 min, 2.5 h and 2.5 h in mouth, stomach and duodenum, respectively; the optimal pH values of 1.1 and 7.8 for gastric juice and duodenal fluid; the volume of 5, 12, 13 and 6 ml for saliva, gastric juice, intestinal fluid and bile, respectively. The bioaccessibilities of both AFB(1) and AFB(2) were highest at the fasting state (83.1% and 89.3% respectively). The bioaccessibilities decreased with the increasing of stomach contents, but the changes in bioaccessibility were not significant when the stomach contents reached the semi-feeding state or more. From semi-feeding to feeding state, the biocessibilities of AFB(1) decreased from 72.8% to 71.5% and AFB(2) decreased from 78.3% to 76.9%. Chlorophyll and activated charcoal were the strongest absorbent in reducing the bioaccessibilities of AFB(1) and AFB(2), and the bioaccessibilities decreased to 0.8% and 1.3% respectively.</p><p><b>CONCLUSION</b>The in vitro digestion model developed in the present study is stable and reproducible, and meets the requirements for assessing the bioaccessibilities of AFB(1) and AFB(2) in foods.</p>

Dietary iodine intake in the Chinese population / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To evaluate dietary iodine intake and its potential risks among the Chinese population.</p><p><b>METHODS</b>Individual dietary iodine intake was calculated using food consumption data multiplying by iodine concentration in foods, table salt and drinking water, followed by summing, and then compared with the corresponding age-specific reference values, including Upper Intake Level (UL) and Recommended Nutrient Intake (RNI).</p><p><b>RESULTS</b>In areas with water iodine concentration (WI) lower than 150 μg/L, 80.8% of residents had iodine intake between the RNI and UL, 5.8% higher than UL, and the remaining (13.4%) lower than RNI if iodized salt was consumed. However, in the uniodized salt consumption scenario, only 1.0% of residents between RNI and UL, 1.4% higher than UL, and a large part of residents (97.6%) lower than RNI. In areas with WI higher than 150 μg/L, all residents had iodine intake between RNI and UL if iodized salt was consumed, except 10.5% and 24.9% of residents higher than UL in areas with WI at 150-300 μg/L and higher than 300 μg/L respectively. However, in the uniodized salt consumption scenario, only 1.5% and 1.7% of residents had higher iodine intake than UL respectively.</p><p><b>CONCLUSION</b>The findings suggested that in general, the dietary iodine intake by the Chinese population was appropriate and safe at the present stage. People in areas with WI lower than 150 μg/L were more likely to have iodine deficiency. While people in areas with WI higher than 150 μg/L were more likely to have excessive iodine intake if iodized salt was consumed.</p>

Development of pulsed field gel electrophoresis and application for characterization and identification of Lactobacillus and Streptococcus thermophilus / 中华预防医学杂志

<p><b>OBJECTIVE</b>To develop a pulsed field gel electrophoresis (PFGE) method for molecular typing of Lactobacillus and Streptococcus thermophilus (S. thermophilus) and to apply it in identification and characterization of both bacteria isolated from yoghurt collected from Beijing supermarket.</p><p><b>METHODS</b>The five most useful restriction enzymes including Apa I, Not I, Sfi I, Xba I and Sma I were chosen to cut DNA of 52 strains of Lactobacillus, S. thermophilus as well as associated standard bacteria strains. The endonucleases and electrophoresis conditions for PFGE analysis were optimized and applied in molecular typing of Lactobacillus and S.thermophilus isolates. Cluster analysis based on the PFGE data was conducted. The identification results of PFGE were compared with those obtained in biochemical and 16s ribosomal RNA PCR identification tests.</p><p><b>RESULTS</b>Not I was suitable for L. bulgaricus, L. fermentum and L. delbrueckii digestion. While Apa I was an appropriate endonuclease for S. thermophilus, L. acidophilus and L. casei digestion. The results of molecular typing indicated that 24 strains of L.bulgaricus and 15 strains of S. thermophilus were grouped into 8 types by PFGE method, respectively. While 7 strains of L.acidophilus were grouped into 3 types and 2 strains of L. delbrueckii were grouped into 2 different PFGE types.</p><p><b>CONCLUSION</b>The results of PFGE analysis are in compliance with those of 16s rRNA PCR and biochemical identification. The PFGE method developed in this study is suitable for molecular characterization of both Lactobacillus and S. thermophilus.</p>

Natural occurrence of masked deoxynivalenol and multi-mycotoxins in cereals from China harvested in 2007 and 2008 / 中华预防医学杂志

<p><b>OBJECTIVE</b>To elucidate the natural occurrence of masked deoxynivalenol (DON-3-G) and other multi-mycotoxins in cereals from parts of China.</p><p><b>METHODS</b>A total of 446 corn and wheat samples harvested in 2007 and 2008 collected from Henan, Hebei, Guangxi, Anhui, Sichuan, Chongqing and Jiangsu provinces were analyzed for DON-3-G and other multi-mycotoxins (including deoxynivalenol (DON), zearalenone (ZEN), nivalenol (NIV), et al) by UPLC-MS/MS.</p><p><b>RESULTS</b>Corn and wheat samples were mainly contaminated by DON and its derivatives as well as ZEN.88% (169/192) of wheat samples were positive for DON (range: 1.5 - 590.7 µg/kg; median: 30.8 µg/kg); 22.9% (44/192) of wheat samples were contaminated with ZEN (range: 1.7 - 3425.0 µg/kg; median: 8.0 µg/kg) and six samples contained ZEN concentration higher than the ZEN tolerance limit of 60 µg/kg. DON was detected in 50.5% (103/204) corn samples (range: 1.6 - 4374.4 µg/kg; median: 94.9 µg/kg); Seven samples contained DON exceeding the tolerance limit of 1000 µg/kg for DON. Additionally, ZEN was found in 41.7% (85/204) corn samples with the concentration between 1.6 µg/kg and 4808.7 µg/kg (median: 48.5 µg/kg) and there were 37 corn samples with ZEN level in the excess of tolerance limit for ZEN (60 µg/kg). DON-3-G was detected in corn and wheat samples for the first time in China with the median level of 21.4 µg/kg and 34.6 µg/kg for wheat and corn, respectively. Wheat was more heavily contaminated with DON-3-G than both 3-acetyl-DON (3-A-DON, median: 4.1 µg/kg) and 15-acetyl-DON (15-A-DON, median: 3.1 µg/kg) (t values were 5.111 and 5.966, respectively, both P values < 0.01). While, the level of 15-A-DON (median: 48.6 µg/kg) in corn was higher than 3-A-DON (median: 6.8 µg/kg) (t = -3.579, P < 0.01). The concentration of DON, DON-3-G, 3-A-DON, 15-A-DON and ZEN in corn were higher than that in wheat (Z values were -3.492, -1.960, -2.467, -8.711 and -6.272, respectively, all P values < 0.05). Wheat (median: 29.0 µg/kg) contained higher NIV in comparison with corn (median: 18.2 µg/kg, Z = -2.086, P < 0.05).</p><p><b>CONCLUSION</b>Wheat and corn samples from parts of China were contaminated with multi-mycotoxins and DON was the predominant;in comparison of wheat, corn was more heavily contaminated with DON, DON-3-G, 3-A-DON, 15-A-DON and ZEN.</p>

Biological activities of the coagulation factor VIII, IX in platelet concentrates collected by platelet apheresis during preservation / 中国实验血液学杂志

The study was to explore the change of coagulation factor VIII and IX activities in the platelet suspension collected by platelet apheresis during storage at 22 degrees C. 18 samples of platelet concentrates were collected by the cs-3000 plus and stored at 22 degrees C and then FVIII: C, FIX: C activities were detected at 0, 12, 24, 48, 72, 96, 120 hours respectively by SYSMEX CA-1500. The results showed that FVIII: C activity was (100.51 + 44.02)% at 0 hour, and then decreased dramatically to 10% - 40% of primary level from 12 to 120 hours, while FIX: C activity was (120.93 +/- 20.50)% at 0 hour and decreased to 10% - 35% of primary level from 24 to 120 hours. In conclusion, FVIII and FIX in the platelet concentrates stored at 22 degrees C could keep their biological activities at physiologically high levels.

Effect of beta-Fibrinogen-455 Gene Polymorphism on Plasma Fibrinogen Levels in Patients with Ischemic Stroke / 中国实验血液学杂志

In large prospective studies, plasma fibrinogen levels have been shown to be an independent risk factor of vascular disease, including ischemic stroke. Elevated plasma fibrinogen in an individual could be due to the presence of predisposing genetic and/or environmental factors, such as smoking. Of the polymorphisms studies to date, the beta-fibrinogen-455 (beta-Fg-455) G-->A substitution in the 5' flanking region is associated with the most consistent difference in plasma fibrinogen levels in both case-control studies and in selected groups of healthy individuals. In order to further elucidate the role of the beta-Fg-455 G-->A substitution in determining fibrinogen levels and susceptibility to ischemic stroke in case-control population, including 104 individuals with verified ischemic stroke and 156 healthy individuals. Turbidimetriy assays were used to measure plasma fibrinogen levels of all samples. The beta-Fg-455 G-->A mutation was identified by the polymerase chain reaction followed by restriction enzyme digestion of the amplified DNA with HaeIII. The plasma fibrinogen level in patients with ischemic stroke [(3.51 +/- 1.09) g/L] was significantly higher than that in the control [(3.08 +/- 0.71) g/L] (P < 0.01). The A-allele is associated with elevated fibrinogen levels in both patients and controls. The plasma fibrinogen levels in controls with A-allele in elder people were higher than in younger people (P < 0.05). Those with A allele in males of ischemic stroke had significantly higher plasma fibrinogen levels in smokers than in non-smokers and ex-smokers (P < 0.05), but it was not significantly difference in subjects of GG genotype (P > 0.05). Our data demonstrates an association of the beta-Fg promoter A-455 allele with higher fibrinogen levels in the general population, and suggests that the A-allele may be a susceptible predictor of ischemic stroke, particularly in aging and smoking.

Monascus Citrinin Analysis Methods and A Study on Formation of Citrillin by Monascus / 微生物学通报

A HPLC method of analysis of Monascus citrinin was established. More than 30 strains of Monascus spp. were cultured in steamed rice at solid state or in MSG liquid medium composed of monosodium glutamate as sole nitrogen source and glucose as sole carbon to investigate their ability of producing citrinin. The results indicated that most of the Monascus strains are able to produce citrinin. MSG medium can be used as a specific culture medium to qualitatively identify if the strain is the potential citrinin producer. But to confirm whether the Monascus strains are potential citrinin producers, these strains should be cultured in several cultivation methods, as the culture states and culture conditions influence the citrinin production greatly.