1. Study on identification of cordyceps-a Chinese traditional medicine
Chinese Pharmaceutical Journal 2014;49(4):283-286
OBJECTIVE: To study on the identification of Cordyceps and establish its traditional pharmacognostic identification and modern identification method based on DNA molecular marker technology. METHODS: The methods of macroscopic, microscopic examination and RAPD-SCAR were employed here to authenticate Cordyceps. RESULTS: Based on the macroscopic identification, the features of transverse section and powder of Cordyceps were described in detail. The digital photographs were presented here in repealing the main macroscopic and microscopic characteristic of Cordyceps. The specific RAPD fragment of Cordyceps was conversed into SCAR marker, and Cordyceps could be identified by the optimized PCR conditions. CONCLUSION: The authenticated method of microscopic and macroscopic identification is intuitive. However, the identification method based on DNA molecular marker is sample, which provides the new scientific evidences for the identification of authenticity of Cordyceps.
2.Effects of quaternary ammonium chain length on the antibacterial and remineralizing effects of a calcium phosphate nanocomposite
Zhang KE ; Cheng LEI ; Weir D MICHAEL ; Bai YU-XING ; Xu HK HOCKIN
International Journal of Oral Science 2016;8(1):45-53
Composites containing nanoparticles of amorphous calcium phosphate (NACP) remineralize tooth lesions and inhibit caries. A recent study synthesized quaternary ammonium methacrylates (QAMs) with chain lengths (CLs) of 3–18 and determined their effects on a bonding agent. This study aimed to incorporate these QAMs into NACP nanocomposites for the first time to simultaneously endow the material with antibacterial and remineralizing capabilities and to investigate the effects of the CL on the mechanical and biofilm properties. Five QAMs were synthesized: DMAPM (CL3), DMAHM (CL6), DMADDM (CL12), DMAHDM (CL16), and DMAODM (CL18). Each QAM was incorporated into a composite containing 20% NACP and 50% glass fillers. A dental plaque microcosm biofilm model was used to evaluate the antibacterial activity. The flexural strength and elastic modulus of nanocomposites with QAMs matched those of a commercial control composite (n 5 6; P . 0.1). Increasing the CL from 3 to 16 greatly enhanced the antibacterial activity of the NACP nanocomposite (P , 0.05); further increasing the CL to 18 decreased the antibacterial potency. The NACP nanocomposite with a CL of 16 exhibited biofilm metabolic activity and acid production that were 10-fold lesser than those of the control composite. The NACP nanocomposite with a CL of 16 produced 2-log decreases in the colony-forming units (CFU) of total microorganisms, total streptococci, and mutans streptococci. In conclusion, QAMs with CLs of 3–18 were synthesized and incorporated into an NACP nanocomposite for the first time to simultaneously endow the material with antibacterial and remineralization capabilities. Increasing the CL reduced the metabolic activity and acid production of biofilms and caused a 2-log decrease in CFU without compromising the mechanical properties. Nanocomposites exhibiting strong anti-biofilm activity, remineralization effects, and mechanical properties are promising materials for tooth restorations that inhibit caries.
4.Preparation of doxorubicin-loaded chitosan polymeric micelle and study on its tissue biodistribution in mice.
Xiang-yang XU ; Jian-ping ZHOU ; Ling LI ; Yong ZHANG ; Mei-rong HUO ; Xing WANG ; Lin LÜ
Acta Pharmaceutica Sinica 2008;43(7):743-748
To prepare doxorubicin-loaded N-octyl-N'-succinyl chitosan polymeric micelle (DOX-OSC) and study the biodistribution of DOX-OSC in mice, DOX-OSC was prepared by dialysis method. By using doxorubicin injection (DOX-INJ) as control, DOX-OSC and DOX-INJ were administered to mice through caudal vein at a dose of 5 mg x kg(-1) body weight. The RP-HPLC method was established to determine the DOX levels in the plasma and other tissues of mice. The tissues distribution and targeting efficiency were evaluated by pharmacokinetic parameters (AUC, MRT) and targeting parameters (Re, Ce and Te). The drug loading and entrapment efficiency of DOX-OSC were (35.8 +/- 0.4)% and (75.3 +/- 1.1)%, respectively. The diameter and zeta potential of DOX-OSC were (174 +/- 12) nm and (-37.1 +/- 3.0) mV, respectively. The transmission electron microscope result showed DOX-OSC with spherical shape. The biodistribution results showed that the concentration of DOX of both DOX-OSC and DOX-INJ decreased rapidly in blood after iv administration. While free DOX levels in blood at 12-96 h were not detectable for DOX-INJ, in contrast, DOX level in blood at 96 h was still found for DOX-OSC. In contrast to DOX-INJ group, DOX-OSC showed a higher targeting efficiency in the liver and spleen. The AUCs of DOX in the liver and spleen were 20.0 and 47.4 times and the MRT were 11.2 and 37.2 times, respectively. And the levels of DOX-OSC in the heart and kidney tissues were significantly reduced. And the drug distribution of DOX-OSC in the heart and kidney tissues were 17.0% and 11.4%, respectively. Hence, DOX-OSC shows an excellent drug loading capabilities and a higher targeting efficiency in the liver and spleen. That the levels of DOX-OSC in the heart and kidney tissues are significantly reduced, might improve the treatment efficacy of DOX and decrease the side effects.
Animals
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Antibiotics, Antineoplastic
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administration & dosage
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pharmacokinetics
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Area Under Curve
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Chitosan
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analogs & derivatives
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chemistry
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Doxorubicin
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administration & dosage
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pharmacokinetics
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Drug Carriers
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Drug Delivery Systems
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Female
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Liver
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metabolism
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Male
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Mice
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Micelles
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Particle Size
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Polymers
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Spleen
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metabolism
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Tissue Distribution
5.Determination of iridoids and triterpenes in herb of Swertia pseudochinesis by RP-HPLC.
Wen-Zhe HUANG ; Chun-Hui XU ; Da-Cheng ZHOU ; Li-Hua TONG ; Zu-Guang YE
China Journal of Chinese Materia Medica 2007;32(23):2494-2496
OBJECTIVETo establish a RP-HPLC method for the determination of swertiamarin, sweroside, gentiopicrin and oleanolic acid in different parts of Swertia pseudochinesis.
METHODA Zorbax SB-C18 (4.6 mm x 250 mm, 5 microm) column was used with acetonitrile-water (10:90) and methnol-water(86:14) at detection wavelengths of 238 nm, 246 nm, 274 nm and 207 nm for swertiamarin, sweroside, gentiopicrin and oleanolic acid respectively. The flow rate was 1.0 mL x min(-1) and the column temperature was 25 degrees C.
RESULTAll of the compounds were based--isolated. The linear ranges of swertiamarin, sweroside, gentiopicrin and oleanolic acid were 0.068 9-0.344 4(r = 0.999 2) , 0.001 1-0.014 0 (r2 = 0. 999 8), 0.001 1-0.013 4 (r2 = 0.999 9) and 0.001 1-0.008 8 mg x mL(-1) (r2 = 0. 999 6), respectively.
CONCLUSIONThe method is simple and accurate, which can be used for quality control of S. pseudochinesis.
Chromatography, High Pressure Liquid ; methods ; Flowers ; chemistry ; Glucosides ; analysis ; Iridoid Glucosides ; Iridoids ; analysis ; Oleanolic Acid ; analysis ; Plant Leaves ; chemistry ; Plant Roots ; chemistry ; Plant Stems ; chemistry ; Plants, Medicinal ; chemistry ; Pyrones ; analysis ; Reproducibility of Results ; Swertia ; chemistry ; Triterpenes ; analysis
6.Indoor mite allergen levels, specific IgE prevalence and IgE cross-inhibition pattern among asthmatic children in Haikou, southern China.
Yi-Wu ZHENG ; Shi CHEN ; Xu-Xin LAI ; Birgitte GJESING ; Nan-Shan ZHONG ; Michael D SPANGFORT
Chinese Medical Journal 2012;125(17):3059-3063
BACKGROUNDHaikou locates in tropical island with unique mite propagation. The aim of this stuy is to determine mite allergens levels in Haikou, and to investigate the prevalence of mite specific IgE-sensitization and IgE cross-reactivity between house dust mites.
METHODSAllergen and antigen concentrations against six mite species were tested by enzyme-linked immunosorbent assay (ELISA). Specific IgE concentrations and cross-inhibitions were measured with ADVIA Centaur(®).
RESULTSAllergen or antigen Dermatophagoides pteronyssinus (Der p 1), Blomia tropicalis (Blo t) and Tyrophagus putrescentia (Tyr p) were detected in dust samples. Dermatophagoides farinae (Der f 1), Lepidoglyphus destructor (Lep d 2), and Acarus siro (Aca s) were found in very few samples. Specific IgE tests showed high prevalence of sensitizations against all tested mites with high IgE levels to Der p, Der f, and Blo t. Storage mites, Blo t, Tyr p, Lep d, and Aca s, could inhibit Der p from 0 to 50%. Storage mites could inhibit Der f between 30% and 100%. Der p IgE could be inhibited by Der f with up to 90%, and vice versa. Der p could inhibit Blo t from 40% to 80%. Blo t was able to fully inhibit IgE binding to Lep d, Tyr p, and Aca s compared to partial inhibition by Der p.
CONCLUSIONSDer p is the dominating mite and has the highest specific IgE prevalence among asthmatic children. Blo t represents an important source of storage mite sensitization and some patients may be independently sensitized to both Der p and Blo t. High prevalence of sensitization to Der f may be due to IgE-mediated cross-reactivity with Der p and Blo t.
Adolescent ; Air Pollution, Indoor ; Allergens ; analysis ; Animals ; Antigens, Dermatophagoides ; analysis ; Arthropod Proteins ; analysis ; Asthma ; immunology ; Child ; Child, Preschool ; China ; Cross Reactions ; Cysteine Endopeptidases ; analysis ; Dust ; Humans ; Immunoglobulin E ; blood ; immunology ; Mites ; immunology
7.Old and new classes of glucose-lowering agents as treatments for non-alcoholic fatty liver disease: A narrative review
Lei MIAO ; Jing XU ; Giovanni TARGHER ; Christopher D BYRNE ; Ming-Hua ZHENG
Clinical and Molecular Hepatology 2022;28(4):725-738
Non-alcoholic fatty liver disease (NAFLD) has become the most common chronic liver disease with a global prevalence of about 55% in people with type 2 diabetes mellitus (T2DM). T2DM, obesity and NAFLD are three closely inter-related pathological conditions. In addition, T2DM is one of the strongest clinical risk factors for the faster progression of NAFLD to non-alcoholic steatohepatitis (NASH), cirrhosis and hepatocellular carcinoma. Increasing evidence suggests that newer classes of glucose-lowering drugs, such as peroxisome proliferator-activated receptor agonists, glucagon-like peptide-1 receptor agonists, dipeptidyl peptidase-4 inhibitors or sodium-glucose cotransporter-2 inhibitors, could reduce the rates of NAFLD progression. This narrative review aims to briefly summarize the recent results from randomized controlled trials testing the efficacy and safety of old and new glucose-lowering drugs for the treatment of NAFLD or NASH in adults both with and without coexisting T2DM.
8.One-year water-ageing of calcium phosphate composite containing nano-silver and quaternary ammonium to inhibit biofilms
Cheng LEI ; Zhang KE ; Zhou CHEN-CHEN ; Weir D MICHAEL ; Zhou XUE-DONG ; Xu HK HOCKIN
International Journal of Oral Science 2016;8(3):172-181
Dental composites are commonly used restorative materials; however, secondary caries due to biofilm acids remains a major problem. The objectives of this study were (1) to develop a composite containing quaternary ammonium dimethacrylate (QADM), nanoparticles of silver (NAg), and nanoparticles of amorphous calcium phosphate (NACP), and (2) to conduct the first investigation of the mechanical properties, biofilm response and acid production vs water-ageing time from 1 day to 12 months. A 4 × 5 design was utilized, with four composites (NACP-QADM composite, NACP-NAg composite, NACP-QADM-NAg composite, and a commercial control composite), and five water-ageing time periods (1 day, and 3, 6, 9, and 12 months). After each water-ageing period, the mechanical properties of the resins were measured in a three-point flexure, and antibacterial properties were tested via a dental plaque biofilm model using human saliva as an inoculum. After 12 months of water-ageing, NACP-QADM-NAg had a flexural strength and elastic modulus matching those of the commercial control (P40.1). Incorporation of QADM or NAg into the NACP composite greatly reduced biofilm viability, metabolic activity and acid production. A composite containing both QADM and NAg possessed a stronger antibacterial capability than one with QADM or NAg alone (Po0.05). The anti-biofilm activity was maintained after 12 months of water-ageing and showed no significant decrease with increasing time (P40.1). In conclusion, the NACP-QADM-NAg composite decreased biofilm viability and lactic acid production, while matching the load-bearing capability of a commercial composite. There was no decrease in its antibacterial properties after 1 year of water-ageing. The durable antibacterial and mechanical properties indicate that NACP-QADM-NAg composites may be useful in dental restorations to combat caries.
9.Primer containing dimethylaminododecyl methacrylate kills bacteria impregnated in human dentin blocks
Chen CHEN ; Cheng LEI ; Weir D MICHAEL ; Lin J NANCY ; Lin-Gibson SHENG ; Zhou XUE-DONG ; Xu HK HOCKIN
International Journal of Oral Science 2016;8(4):239-245
Antibacterial dimethylaminododecyl methacrylate (DMADDM) was recently synthesized. The objectives of this study were to:(1) investigate antibacterial activity of DMADDM-containing primer on Streptococcus mutans impregnated into dentin blocks for the first time, and (2) compare the antibacterial efficacy of DMADDM with a previous quaternary ammonium dimethacrylate (QADM). Scotchbond Multi-Purpose (SBMP) bonding agent was used. DMADDM and QADM were mixed into SBMP primer. Six primers were tested:SBMP control primer P, P+2.5%DMADDM, P+5%DMADDM, P+7.5%DMADDM, P+10%DMADDM, and P+10%QADM. S. mutans were impregnated into human dentin blocks, and each primer was applied to dentin to test its ability to kill bacteria in dentinal tubules. Bacteria in dentin were collected via a sonication method, and the colony-forming units (CFU) and inhibition zones were measured. The bacterial inhibition zone of P+10%DMADDM was 10 times that of control primer (Po0.05). CFU in dentin with P+10%DMADDM was reduced by three orders of magnitude, compared with control. DMADDM had a much stronger antibacterial effect than QADM, and antibacterial efficacy increased with increasing DMADDM concentration. Dentin shear bond strengths were similar among all groups (P40.1). In conclusion, antibacterial DMADDM-containing primer was validated to kill bacteria inside dentin blocks, possessing a much stronger antibacterial potency than the previous QADM. DMADDM-containing bonding agent was effective in eradicating bacteria in dentin, and its efficacy was directly proportional to DMADDM mass fraction. Therefore, DMADDM may be promising for use in bonding agents as well as in other restorative and preventive materials to inhibit bacteria.
10.Preferential expression of cytochrome CYP CYP2R1 but not CYP1B1 in human cord blood hematopoietic stem and progenitor cells.
Shuoqi XU ; Zhihua REN ; Yanan WANG ; Xinxin DING ; Yongping JIANG ;
Acta Pharmaceutica Sinica B 2014;4(6):464-469
Cytochrome P450 (CYP) enzymes metabolize numerous endogenous substrates, such as retinoids, androgens, estrogens and vitamin D, that can modulate important cellular processes, including proliferation, differentiation and apoptosis. The aim of this study is to characterize the expression of CYP genes in CD34+ human cord blood hematopoietic stem and early progenitor cells (CBHSPCs) as a first step toward assessment of the potential biological functions of CYP enzymes in regulating the expansion or differentiation of these cells. CD34+ CBHSPCs were purified from umbilical cord blood via antibody affinity chromatography. Purity of CD34+ CBHSPCs was assessed using fluorescence-activated cell sorting. RNA was isolated from purified CD34+ CBHSPCs and total mononuclear cells (MNCs) for RNA-PCR analysis of CYP expression. Fourteen human CYPs were detected in the initial screening with qualitative RT-PCR in CD34+ CBHSPCs. Further quantitative RNA-PCR analysis of the detected CYP transcripts yielded evidence for preferential expression of CYP2R1 in CD34+ CBHSPCs relative to MNCs; and for greater expression of CYP1B1 in MNCs relative to CD34+ CBHSPCs. These findings provide the basis for further studies on possible functions of CYP2R1 and CYP1B1 in CBHSPCs׳ proliferation and/or differentiation and their potential utility as targets for drugs designed to modulate CD34+ CBHSPC expansion or differentiation.