A ratiometric fluorescent probe for simultaneous detection of L-ascorbic acid and alkaline phosphatase activity based on red carbon dots/polydopamine nanocomposite.

Herein, efficient red carbon dots (R-CDs) were synthesized by one-step hydrothermal treatment of N-(4-amino phenyl) acetamide and (2,3-difluoro phenyl) boronic acid. The optimal emission peak of R-CDs was at 602 nm (under 520 nm excitation) and the absolute fluorescence quantum yield of R-CDs was 12.9%. Polydopamine, which was formed by the self-polymerization and cyclization of dopamine in alkaline condition, emitted characteristic fluorescence with peak position of 517 nm (under 420 nm excitation) and affected the fluorescence intensity of R-CDs through inner filter effect. L-Ascorbic acid (AA), which was the hydrolysis product of L-ascorbic acid-2-phosphate trisodium salt under the catalytic reaction of alkaline phosphatase (ALP), effectively prevented the polymerization of dopamine. Combined with the ALP-mediated AA production and the AA-mediated polydopamine generation, the ratiometric fluorescence signal of polydopamine with R-CDs was correlated closely with the concentration of both AA and ALP. Under optimal conditions, the detection limits of AA and ALP were 0.28 µM during linear range of 0.5-30 µM and 0.044 U/L with linear range of 0.05-8 U/L, respectively. This ratiometric fluorescence detection platform can efficiently shield the background interference of sophisticated samples by introducing a self-calibration as reference signal in a multi-excitation mode, which can detect AA and ALP in human serum samples with satisfactory results. Such R-CDs/polydopamine nanocomposite provides a steadfast quantitative information and makes R-CDs be excellent candidate for biosensors via combining target recognition strategy.

Rapid microwave fabrication of red-carbon quantum dots as fluorescent on-off-on probes for the sequential determination of Fe(III) ion and ascorbic acid in authentic samples.

In this study, fluorescent red-carbon quantum dots (R-CQDs) with an ultrahigh fluorescence quantum yield of 45% were rapidly and easily synthesized by thermal pyrolysis of 2,5-diaminotoluene sulfate and 4-hydroxyethylpiperazineethanesulfonic acid using a one-step microwave-assisted hydrothermal approach. R-CQDs possessed the excitation-independent fluorescence property with the optimal emission peak at 607 nm under the excitation wavelength of 585 nm. R-CQDs exhibited excellent fluorescence stability under extremely harsh conditions in a pH range of 2-11, high ionic strength (1.8 M of NaCl), and long UV light irradiation time (160 min). The fluorescence quantum yield of these R-CQDs was as high as 45%, implying their preferable application in chemosensors and biological analysis. Because Fe3+ ion bound with R-CQDs and statically quenched the fluorescence of R-CQDs, the fluorescence intensity of R-CQDs was recovered after the addition of ascorbic acid (AA) via its redox reaction with Fe3+ ion. R-CQDs were developed as highly sensitive fluorescent on-off-on probes for sequentially sensing Fe3+ ions and AA. Under the optimal experimental conditions, the linear range for Fe3+ ion detection was 1-70 µM with a detection limit of 0.28 µM, and the linear range for AA detection was 1-50 µM with a detection limit of 0.42 µM. The successful detection of Fe3+ ions in authentic water samples and the successful sensing of AA in human body fluids and vitamin C tablets further proved the practical application prospects of this efficient strategy in the environmental protection and disease diagnosis fields.

TCM Treatment Rule of Lung Cancer in Hubei Cancer Hospital Based on Data Mining and Complex Network Analysis / 肿瘤防治研究

Objective To explore the medication for lung cancer treatment at Hubei Cancer Hospital. Methods The electronic cases of 3 234 hospitalized lung cancer patients in Hubei Cancer Hospital were collected. The medication of the Peiyuan Guben method in treating lung cancer was analyzed with cluster and association analyses by the Apriori association rule algorithm in IBM SPSS modeler 18.0 and Qihuang data AI workstation software system. Results In the 11 293 pieces of traditional Chinese medicine used in 3 234 patients with lung cancer, the core prescription of 16 core drugs were Astragalus, Coix seed, Poria, Coke hawthorn, Ligustrum lucidum, Wolfberry, Bran fried atractylodes, Mushroom stem, Bran fried citrus husk, Bittersweet herb, Centipede, Rhodiola, Semiaquilegia adoxoides, Seaweed, Prunella and Pseudobulbus cremastrae seu pleiones. Conclusion "Peiyuan Guben" is an effective method of traditional Chinese medicine in treating lung cancer. Traditional Chinese medicine with the effects of Yiqi Jianpi and Bushen Yijing has an evident curative effect in treating lung cancer and can improve patients' quality of life.

Fluorine and nitrogen co-doped near-infrared carbon dots for fluorescence "on-off-on" determination of nitrite.

A fluorescence "on-off-on" strategy was established for the determination of nitrite in aqueous solution based on fluorine and nitrogen co-doped near-infrared carbon dots (NIR-CDs). NIR-CDs were prepared via one-step hydrothermal method by using N-(4-aminophenyl)-acetamide and 4,5-difluorobenzene-1,2-diamine as precursors. The photoluminescence quantum yield of NIR-CDs reaches to 17.4%, and the optimal emission peak of NIR-CDs is 675 nm under excitation of 530 nm. The Stokes shift of NIR-CDs (145 nm) is higher than that of some CDs with longer emission wavelengths. The red bathophenanthroline disulfonic acid (BPS)-Fe2+ complex can quench the fluorescence of NIR-CDs via inner filter effect and static quench modes. Nitrite can oxidize Fe2+ to produce Fe3+ in acidic environment, resulting in not only the formation of colorless and unstable BPS-Fe3+ complex but also the fluorescence recovery of NIR-CDs. This fluorescence "on-off-on" phenomenon also comes with the color variation of the mixture, resulting in both the fluorescence and the visual determination of nitrite. Under optimal conditions, this assay exhibits a good linear range from 1 to 50 µM and a low detection limit of 0.056 µM for nitrite determination. The method showed good applicability for nitrite determination in soil extract, human urine, and water samples with acceptable results. A convenient fluorescence "on-off-on" strategy for nitrite detection based on fluorine and nitrogen co-doped near-infrared carbon dots (NIR-CDs) and bathophenanthroline disulfonic acid (BPS)-Fe2+ complex was innovatively established. This probe showed a low detection limit of 0.056 µM for nitrite in authentic samples, which offered a new sight for fluorescent and visual detection of nitrite in environmental protection and human health areas.

Ultrasensitive ratiometric fluorescent probes for Hg(II) and trypsin activity based on carbon dots and metalloporphyrin via a target recycling amplification strategy.

A convenient and ultrasensitive ratiometric fluorescent probe was innovatively developed for Hg(II) detection and trypsin activity evaluation based on carbon dots (CDs) and tetraphenylporphyrin tetrasulfonic acid (TPPS) using bovine serum albumin (BSA) as the substrate of trypsin. The ratiometric fluorescence signal arises from CDs (λem = 506 nm) and TPPS (λem = 645 nm) via an inner filter effect. Hg2+ can trigger the formation of TPPS-Mn2+ metalloporphyrin for target Hg2+ recycling amplification, while both TPPS-Hg2+ and TPPS-Mn2+ metalloporphyrins do not affect the fluorescence of CDs. Small amino acids and peptide fragments, which are the products of BSA under the digestion of trypsin, bind stronger with Hg2+ than with TPPS. The decomposition of both TPPS-Hg2+ and TPPS-Mn2+ metalloporphyrins leads to a variation in the ratiometric fluorescence signal. Under optimized conditions, this probe provided an inspiring detection limit of 0.086 nM for Hg2+ and 0.013 ng mL-1 for trypsin, which possessed acceptable sensitivity for Hg2+ detection and trypsin activity evaluation in authentic samples. This unprecedented CD-based ratiometric fluorescence proposal for ultrasensitive quantification of Hg2+ concentration and selective assessment of trypsin activity gives a new insight for designing metal ion assays or enzymatic activity bioassays under different enzymatic substrates in the near future.

Red-emission carbon dots as fluorescent "on-off-on" probe for highly sensitive and selective detection of Cu2+ and glutathione.

A highly sensitive and selective fluorescent "on-off-on" strategy is established for the synchronous detection of Cu2+ and glutathione in aqueous solution. Red carbon dots (R-CDs) were prepared by using precursors of 4,5-difluoro-1,2-phenylenediamine and citric acid via a one-step hydrothermal strategy. R-CDs show a relatively long fluorescence lifetime of 3.47 ns under 455 nm excitation and high absolute fluorescent quantum yield of 20.1% with an excitation wavelength of 550 nm. R-CDs exhibit a marked pH-responsive fluorescence property with no significant perturbation from pH 4 to pH 13 even after five cycles. R-CDs with higher concentration of 750 µg·mL-1 exhibit no significant cytotoxicity and good biocompatibility on HeLa cells and A549 cells after incubation for 48 h. The fluorescence of R-CDs at 619 nm (excited at 550 nm) is quenched statically by Cu2+ and recovered by glutathione subsequently, resulting in a fluorescent "on-off-on" assay for the synchronous detection of Cu2+ and glutathione. Under optimal conditions, the linear response covers the Cu2+ concentration range of 1 to 50 µM and the glutathione concentration range of 1 to 70 µM. Detection limits of Cu2+ and glutathione are 0.16 and 0.41 µM, respectively. This fluorescent probe is applied to the determination of Cu2+ and glutathione in authentic samples with satisfying results. Such an assay broadens the potential application of CDs in environmental areas and clinical therapy fields.

Fluorescent aptasensor for detection of live foodborne pathogens based on multicolor perovskite-quantum-dot-encoded DNA probes and dual-stirring-bar-assisted signal amplification / 药物分析学报

In this study,a fluorescent(FL)aptasensor was developed for on-site detection of live Salmonella typhimurium(S.T.)and Vibrio parahaemolyticus(V.P.).Complementary DNA(cDNA)of aptamer(Apt)-functionalized multicolor polyhedral oligomeric silsesquioxane-perovskite quantum dots(cDNA-POSS-PQDs)were used as encoded probes and combined with dual-stirring-bar-assisted signal amplification for pathogen quantification.In this system,bar 1 was labeled with the S.T.and V.P.Apts,and then bar 2 was functionalized with cDNA-POSS-PQDs.When S.T.and V.P.were introduced,pathogen-Apt complexes would form and be released into the supernatant from bar 1.Under agitation,the two complexes reached bar 2 and subsequently reacted with cDNA-POSS-PQDs,which were immobilized on MXene.Then,the encoded probes would be detached from bar 2 to generate FL signals in the supernatant.Notably,the pathogens can resume their free state and initiate next cycle.They swim between the two bars,and the FL signals can be gradually enhanced to maximum after several cycles.The FL signals from released encoded probes can be used to detect the analytes.In particular,live pathogens can be distinguished from dead ones by using an assay.The detection limits and linear range for S.T.and V.P.were 30 and 10 CFU/mL and 102-106 CFU/mL,respectively.Therefore,this assay has broad application potential for simultaneous on-site detection of various live pathogenic bacteria in water.

Integrating target-responsive CD-CdTe QD-based ratiometric fluorescence hydrogel with smartphone for visual and on-site determination of dichlorvos.

A facile, economic, and portable test kit based on target-responsive hydrogel with smartphone detection was fabricated for the accurate determination of dichlorvos in tap water and food samples. Carbon dots (CDs) and CdTe quantum dots (QDs) embedded hydrogel were employed as indicator, and fluorescence of CdTe QDs (645 nm) was dynamically quenched by Cu2+ while that of CDs (490 nm) were non-response for Cu2+, em erging a typical ratiometric fluorescence signal. Acetylcholinesterase hydrolyzed acetylthiocholine to generate thiocholine that bound with Cu2+ strongly via S-Cu-S bond. Dichlorvos as competitive inhibitor for acetylcholinesterase prevented the generation of thiocholine, which blocked the formation of Cu-thiocholine complex and changed the ratiometric fluorescence signal. The signal of the test kit, which was recorded by smartphone's camera, was transduced by ImageJ software into the color parameter that was linearly proportional to the logarithm of dichlorvos concentration. This portable test kit showed wide linear range of 1 to 40 ppb and low detection limit of 0.38 ppb for dichlorvos. This test kit exhibited rapid sample-to-answer detection time (50 min) of dichlorvos in tap water and food samples, and the recoveries were in the range 81.3 to 111% with relative standard deviations of less than 9.1%. A facile and economic portable test kit based on CD-CdTe QD target-responsive hydrogel with smartphone was innovatively fabricated for the accurate determination of organophosphorus pesticides. This portable test kit showed low detection limit of 0.38 ppb for dichlorvos and rapid sample-to-answer detection time (50 min) in tap water and food samples, which offered a new sight for portable monitoring of environmental pollution and food safety.

Bright Mn-doped carbon dots for the determination of permanganate and L-ascorbic acid by a fluorescence on-off-on strategy.

A one-pot hydrothermal synthesis of manganese-doped carbon dots (Mn-CDs) is reported for fluorescent "on-off-on" determination of Mn(VII) and L-ascorbic acid (L-AA) in aqueous solution and living cells. Mn-CDs were prepared by using sulfanilic acid, tetrakis(hydroxymethyl)phosphonium chloride, and Mn(II) chloride as precursors. Mn-CDs were characterized by several spectroscopic methods and microscopic techniques. Mn-CDs show distinctly long fluorescence lifetime (12.39 ± 0.07 ns) and high absolute fluorescence quantum yield (around 37%) with excitation and emission wavelengths of 362 and 500 nm, respectively. Mn-CDs exhibit no significant cytotoxicity to human cervical carcinoma HeLa cells and human embryonic kidney HEK-293T cells at 200 µg mL-1 level after 48 h incubation. The fluorescence of Mn-CDs at 500 nm (excited at 362 nm) is quenched efficiently by Mn(VII) and can be further recovered after the addition of L-AA, resulting in a fluorescent "on-off-on" assay for the determination of Mn(VII) and L-AA. Under optimal experimental conditions, the linear response covers the 3 to 150 µM Mn(VII) concentration range and the 3 to 140 µM L-AA concentration range. This method offers relatively low detection limits of 0.66 µM for Mn(VII) and 0.90 µM for L-AA. This strategy was applied to visual determination of Mn(VII) and L-AA in living HeLa cells with satisfying results. Graphical abstract Schematic presentation of bright Mn-CD-based fluorescence "on-off-on" assay for both Mn(VII) and L-AA. This fluorescent assay possessed low detection limit of 0.66 µM for Mn(VII) and 0.90 µM for L-AA. This strategy was applied for visual determination of Mn(VII) and L-AA in living HeLa cells with satisfying results.

A ratiometric fluorescent assay for evaluation of alkaline phosphatase activity based on ionic liquid-functionalized carbon dots.

A ratiometric fluorescent assay is fabricated for the evaluation of alkaline phosphatase (ALP) activity. This assay is composed of ionic liquid-functionalized carbon dots (IL-CDs) with blue fluorescence signal at 470 nm and 2,3-diaminophenazine (DAP) with yellow fluorescence signal at 570 nm. IL-CDs were synthesized via electrochemical method by using ionic liquid (1-butyl-3-methylimidazolium tetrafluoroborate) and ultrapure water as precursors. DAP is produced by the oxidation reaction between o-phenylenediamine and H2O2 under the catalysis of horseradish peroxidase. H2O2 is reduced by ascorbic acid which is the hydrolysis product of ascorbic acid 2-phosphate under the catalysis of ALP, finally reducing the amount of DAP. The activity of ALP is evaluated through the ratiometric fluorescent signal between IL-CDs and DAP via Förster resonance energy transfer. Under optimal experimental conditions, this ratiometric fluorescent assay has a response that covers the 0.04 to 3.2 U L-1 (12 to 960 pM) ALP activity. This assay possesses ultralow detection limit of 0.012 U L-1 (3.6 pM) for ALP and high selectivity for ALP among several enzymes. The method was used to measure ALP activity in human serum samples with satisfying results. Graphical abstract Schematic presentation of IL-CDs-based ratiometric fluorescent assay for ALP activity evaluation via FRET strategy between IL-CDs and DAP. This ratiometric fluorescent assay possessed low detection limit of ALP activity (0.012 U L-1) and high selectivity among several enzymes.

Amphiphilic Block Copolymers Bearing Hydrophobic γ-Tocopherol Groups with Labile Acetal Bond.

High concentrations of γ-tocopherol (γTCP) tend to show antioxidant, anti-inflammatory, and anticancer effects. In this study, we prepared polymer micelles under acidic conditions with a controlled release of γTCP due to the decomposition of pendant acetal bonds. First, a precursor diblock copolymer composed of poly(ethylene glycol) (PEG) and acrylic acid (AA) was prepared. This was followed by the synthesis of an amphiphilic diblock copolymer (PEG54-P(AA/VE6/γTCP29)140), incorporated into hydrophobic γTCP pendant groups attached to the main chain through an acetal bond. The prepared PEG54-P(AA/VE6/γTCP29)140 was further dispersed in water to form polymer micelles composed of hydrophobic cores that were generated from a hydrophobic block containing γTCPs and hydrophilic shells on the surface. Under acidic conditions, γTCP was then released from the core of the polymer micelles due to the decomposition of the pendant acetal bonds. In addition, polymer micelles swelled under acidic conditions due to hydration of the core.

Magnetic-induced cell targeted transplantation promotes repair of large segmental femoral defects with tissue engineering bone loaded with fluorescent gene labeled cells / 中华创伤骨科杂志

Objective To investigate the effect of magnetic-induced cell targeted transplantation (MagIC-TT) on repair of bone defects in mice using therapeutic fluorescent gene labeled cells into bone tissue and its mechanism.Methods The proliferation,apoptosis and targeted migration ability were compared between magnetized and unmagnetized murine bone marrow stromal cells labeled with green fluorescent protein (GFP-BMSCs) (n =3).GFP-BMSCs were loaded into tissue engineering bone (TEB) by MagIC-TT in the experimental group (n =5) before the TEB was transplanted into the large femur defects in the model of red fluorescent protein (RFP) transgenic mice.In the control group (n =5) TEB was not loaded with GFP-BMSCs while in the blank group (n =3) the large femur defects were only fixated with intramedullary nails.The effects and mechanism of bone repair were explored 3 months after surgery using X-ray,micro-CT,semi-solid decalcification (SSD) and histology,respectively Results There were no significant differences between magnetized and non-magnetized GFP-BMSCs in proliferation (0.760 ±0.029 versus 0.733 ±0.033) or in survival rate (87.9％ ±1.0％ versus 87.4％ ±2.0％) (P＞ 0.05),but the mobility of magnetized GFP-BMSCs was significantly higher than that of non-magnetized GFP-BMSCs (P ＜ 0.05).The X-ray 3 months after surgery showed that the scaffolds in the experimental group were degraded and that the proximal and distal ends of the femoral defects were connected by new bone tissue.No new bone formation was found in the blank group while a small amount of bone formation was observed in the control group.The Micro-CT showed that stable new bone tissue formed in the femur defects after removal of intramedullary nails in the experimental group.The SSD showed that GFP-MSCs were densely distributed in the scaffolds with red fluorescent protein (RFP) recipient cells penetrating them,indicating involvement of both donor and recipient cells in the formation of new bone.Conclusions MagIC-TT can be used to promote introduction of therapeutic cells into bone tissue to achieve a fine effect on repairing bone defects.Dual fluorescence gene marking combined with SSD shows that both donor and recipient cells may take part in the bone repairing.

Oral microbiological diversity in patients with salivary adenoid cystic carcinoma / 华西口腔医学杂志

OBJECTIVE@#The aim of this study was to identify the differences in microbial diversity and community in patients with salivary adenoid cystic carcinoma (SACC).@*METHODS@#Saliva was collected from 13 patients with SACC confirmed by histopathological diagnosis and 10 healthy control subjects. Total metagenomic DNA was extracted. The DNA amplicons of the V3-V4 hypervariable regions of the 16S rRNA gene were generated and subjected to high-throughput sequencing. Microbial diversity and community structure were analyzed with Mothur software.@*RESULTS@#A total of 16 genera of dominant bacteria in the SACC group were found, including Streptococcus (36.68%), Neisseria (8.55%), Prevotella_7 (7.53%), and Veillonella (6.37%), whereas 15 dominant bacteria in the control group were found, including Streptococcus (18.41%), Neisseria (18.20%), Prevotella_7 (8.89%), Porphyromonas (6.20%), Fusobacterium (5.86%) and Veillonella (5.82%). The statistically different phyla between the two groups were Firmicutes, Proteobacteria and Fusobacterium (P<0.05). The statistically different genera between the two groups were Streptococcus, Neisseria and Porphyromonas (P<0.05), and Capnocytophaga was only detected in patients with SACC.@*CONCLUSIONS@#Significant differences were observed in the oral microorganisms between the two groups.

Magnetic-induced cell targeted transplantation promotes repair of large segmental femoral defects with tissue engineering bone loaded with fluorescent gene labeled cells / 中华创伤骨科杂志

Objective@#To investigate the effect of magnetic-induced cell targeted transplantation (MagIC-TT) on repair of bone defects in mice using therapeutic fluorescent gene labeled cells into bone tissue and its mechanism.@*Methods@#The proliferation, apoptosis and targeted migration ability were compared between magnetized and unmagnetized murine bone marrow stromal cells labeled with green fluorescent protein (GFP-BMSCs) (n=3). GFP-BMSCs were loaded into tissue engineering bone (TEB) by MagIC-TT in the experimental group (n=5) before the TEB was transplanted into the large femur defects in the model of red fluorescent protein (RFP) transgenic mice. In the control group (n=5) TEB was not loaded with GFP-BMSCs while in the blank group (n=3) the large femur defects were only fixated with intramedullary nails. The effects and mechanism of bone repair were explored 3 months after surgery using X-ray, micro-CT, semi-solid decalcification (SSD) and histology, respectively@*Results@#There were no significant differences between magnetized and non-magnetized GFP-BMSCs in proliferation (0.760±0.029 versus 0.733±0.033) or in survival rate (87.9%±1.0% versus 87.4%±2.0%) (P>0.05), but the mobility of magnetized GFP-BMSCs was significantly higher than that of non-magnetized GFP-BMSCs (P<0.05). The X-ray 3 months after surgery showed that the scaffolds in the experimental group were degraded and that the proximal and distal ends of the femoral defects were connected by new bone tissue. No new bone formation was found in the blank group while a small amount of bone formation was observed in the control group. The Micro-CT showed that stable new bone tissue formed in the femur defects after removal of intramedullary nails in the experimental group. The SSD showed that GFP-MSCs were densely distributed in the scaffolds with red fluorescent protein (RFP) recipient cells penetrating them, indicating involvement of both donor and recipient cells in the formation of new bone.@*Conclusions@#MagIC-TT can be used to promote introduction of therapeutic cells into bone tissue to achieve a fine effect on repairing bone defects. Dual fluorescence gene marking combined with SSD shows that both donor and recipient cells may take part in the bone repairing.

Effects of Tangzhi Kangping Granules on the blood sugar and lipid in rats with disordered glucose and lipid metabolism / 中成药

AIM To observe the effects of Tangzhi Kangping Granules (Astragali Radix,Ligustri lucidi Fructus,Schisandrae chinensis Fructus,etc.) on regulating blood sugar and lipid of rats with glucose and lipid metabolism disorders.METHODS Among the seventy rats for the trial,ten rats were randomly assigned to normal control group,the other 60 rats were injected with STZ citric acid-sodium citrate solution (60 mg/kg) combined with high-fat emulsion (10 mL/kg) for 4 weeks to be the models of glucose and lipid metabolism disorders.The model rats were divided into model control group,mefformin + fenofibrate group,Xiaoke Pills + Xuezhikang group,and high,medium and low dose Tangzhi Kangping Granules groups.After 4-week intragastric administration,the rats had their levels of fasting serum glucose (GLU),triglyceride (TG),total cholesterol (TC),high density lipoprotein cholesterol (HDL-C),low density lipids (LDL-C),insulin (INS),adiponectin (ADP),leptin (Leptin),interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) measured.RESULTS Compared with the model control group,the rats in high,medium and low dose Tangzhi Kangping Granules groups displayed significantly decreased serum contents of GLU,TG and TC,lowered levels of LDL-C,ADP,Leptin,IL-6,TNF-α,and yet significantly increased levels of HDL-C and INS.CONCLUSION Tangzhi Kangping Granules,a blood sugar andlipid regulator may adjust the levels of insulin,adiponectin and leptin,and therefore improves the body's inflammatory environment to alleviate insulin resistance.

Gene expression profiling and functional analysis of cerebral artery after experimental subarachnoid hemorrhage / 天津医药

Objective To explore the difference of gene expression profiling between normal basilar arteries and basilar arteries of cerebral vasospasm (CVS) after subarachnoid hemorrhage (SAH) in rabbits. Methods cDNA chip of normal basilar arteries and basilar arteries of CVS after SAH in rabbits were downloaded from GEO database. The chip was analyzed and screened by Bioconductor software, and function enrichment and pathway analysis of the differentially expressed genes were analyzed by Cytoscape software. Then 6 adult male Japanese rabbits were used, and randomly divided into normal control group (n=3) and SAH model group (n=3). Rabbit SAH models were established by cisterna secondary-blood-injection method. RNA data of normal basilar artery specimens on the 0 day and basilar artery specimens after SAH on the 5-day were used to validate the parts of differentially expressed genes by qRT-PCR. Results A total of 4356 differentially expressed genes were found in normal basilar arteries and basilar arteries of CVS after SAH in rabbits. Among them, 920 genes were considered to be significant with P-value<0.05, such as GRIK1, MYH13, ZNF45, SAA3, RLN1, MSR1 and others. Function enrichment analysis indicated that the differentially expressed genes were involved in regulation of Ca2+transmembrane transporter activity, negative regulation of ion transmembrane transport, regulation of potassium ion transport, positive regulation of JAK-STAT signaling cascades and other biological processes. Pathway analysis showed that calcium signaling pathway, cGMP-PKG signaling pathway, HIF-1 signaling pathway, PI3K-Akt signaling pathway and other signaling pathways maybe related with the differentially expressed genes. qRT-PCR verification showed that the expression of MSR1 in SAH model group was consistent with that of the chip result. Conclusion The gene expressions of basilar arteries of CVS after SAH in rabbits are significantly different, and MSR1 gene can be used as a potential target for studying the pathological mechanism of CVS.

Study on lipolysis-oxidation and volatile flavour compounds of dry-cured goose with different curing salt content during production.

The effect of dry-curing salt content (4% low salt (LS), 8% high salt (HS)) on lipolysis, lipid oxidation and volatile compounds in dry-cured goose was investigated in our study. The activities of acid lipase and neutral lipase increased during dry-curing, while phospholipase reached its maximum at the end of marinating. Lipoxygenase (LOX) and thiobarbituric acid reactive substances (TBARS) values increased during dry-curing and marinating then decreased during dry-ripening. Total free fatty acids (TFFA) increased at dry-curing and dry-ripening points and decreased during marinating. Total peak area of lipids derived volatile compounds (TPALDVC) and total peak area increased during entire stages. Compared to LS, HS group has higher lipolytic and LOX activities, TBARS, TFFA, unsaturated fatty acids and TPALDVC. The higher TPALDVC in HS could be attributed to higher lipid hydrolysis and oxidation during processing.

An Ultrasensitive Simultaneous Immunoassay Based on Arsenic and Mercury Ions Labeled SiO2@Au Nanoparticle Probes / 分析化学

An ultrasensitive immunoassay was developed based on As3+ and Hg2+ labeled SiO2 @ Au nanoparticles signal tags and hydride generation-atomic fluorescence spectrometry (HG-AFS) for the detection of carcinoembryonic antigen(CEA) and carbohydrate antigen 19-9 (CA 19-9) respectively. Firstly, amino SiO2@ Au NPs were synthesized for selective absorption of As3+ and Hg2+ ions respectively. Subsequently,the secondary antibody (Ab2) of CEA and CA 19-9 was respectively labeled on As3+ or Hg2+-SiO2 @ Au NPs to prepare the corresponding signal tags for CEA and CA 19-9. Based on the sandwich immunoassay scheme, the tags, two antigen and corresponding first antibodies were bio-conjugated on the bottom of 96-well plate at room temperature to form the immunocomplex. After it was dissolved in alkali solution, As3+ and Hg2+ ions were released in solution and detected by HG-AFS, which concentration was proportional with logarithms of CEA and CA 19-9. The reaction conditions were optimized and the tags were characterized. This assay was based on determination of the concentration of As3+ and Hg2+ for quantization of the corresponding CEA and CA 19-9 antigen. The assay showed a wide linear range from 0. 001 to 100. 0 μg / L for CEA and 0. 01-80 U/ mL for CA 19-9, and a lower detection limit of 0. 5 ng / L and 0. 005 U/ mL respectively. This proposed method was used in real serums samples, the results were consistence with that by ELISA. The immunoassay showed three orders of magnitude of sensitivity lower than that of ELISA, which provides a promising simultaneous immunoassay for the early diagnosis of cancer .

Change of serum levels of matrix metalloproteinase-13 and its inhibitor factor during bone metabolism in Chinese postmenopausal women / 中国综合临床

Objective To investigate the change of the serum matrix metalloproteinase-13 (MMP-13) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) and the correlations of MMP-13 and TIMP-1 with bone metabolic markers or bone mineral density(BMD) in aged postmenopausal Chinese women.Methods One hundred and twenty women aged 48-65 years with postmenopausal were selected as subjects.They were divided into normal group(n =28),low bone mass group (n =36) and osteoporosis group (n =56) accordance with the WHO standard.The levels of serum MMP-13,TIMP-1,estradiol (E2),Osteoprotegerin (OPG),Osteoprotegerin ligand (OPGL),Procollagen terminal propeptide of N (PINP),and Type Ⅰ collagen cross-linked C terminal peptide(CTX) were measured using enzyme linked immunosorbent assay(ELISA).And the ratios of MMP-13 to TIMP-1 were calculated.Bone mineral density(BMD) of the lumbar spine,femoral neck,Fahrenheit and greater trochanter were measured using dual energy X-ray absorptiometry.Results There was significant difference of serum MMP-13 concentrations in normal controls,low bone mass group and osteoporosis group((27.08 ± 1.41) μg/L,(45.64 ± 1.62) μg/L and (44.25 ± 1.21) μg/L; F =110.314,P =000),and serum MMP-13 concentrations in low bone mass group and osteoporosis group higher than that in normal controls (P ＜ 0.05),serum MMP-13 concentrations in low bone mass group higher than that in osteoporosis group,but there was on significant difference(P ＞ 0.05).But Serum TIMP-1 concentrations in three groups was no significant difference (F =10.721,P =0.801).The ratio between MMP-13 and IIMP-1 was 0.185 ± 0.062,0.311 ± 0.053,0.332 ± 0.063 respectively,and there was significant difference of the three groups (F =137.771,P =0.000),and the ratio of the low bone mass group and osteoporosis group higher than the normal group(P ＜0.05),but there was no significant difference between the two groups.In osteoporosis group,Negative correlations between MMP-13,and BMD,E2 and OPGL,were found (r =-0.296,-0.198,-0.301,-0.298,-0.233 respectively,P ＜ 0.05).Meanwhile positive relations were found between MMP-13 and OPG,PINP,CTX (r =0.228,0.315,0.312 respectively,P ＜ 0.05).In low bone mass group,the level of MMP-13 was significantly relative with BMD (the lumbar spine,Fahrenheit),E2 and CTX (r =-0.188,-0.196,-0.235,0.289 respectively,P ＜ 0.05).Conclusion There are significant correlations between serum MMP-13,ratios of MMP-13 and TIMP-1 and bone metabolism marker and BMD.MMP-13 level may increase with increases in osteoporosis and osteopenia.The increases of serum MMP-13 and the decrease of ratio of MMP-13 to TIMP-1 might be biomarkers in high bone turnover state,such as postmenopausal osteoporosis and early stage of osteopenia.

Application of team based learning in teaching of dental endodontics / 中华医学教育探索杂志

Objective To apply team based learning (TBL) in the teaching of dental endodontics for undergraduates in order to expand and deepen the TBL teaching in stomatology education.Methods TBL was used among 2008 grade oral undergraduates in Chongqing Medical University.Average test scores of 2008 grade undergraduates before and intra class were calculated and questionnaire was designed.At the same time,final examination scores between 2007 grade and 2008 grade under-graduates were compared.Results There was no significant correlation in average test scores before and intra class (r =0.027,P ＞ 0.05).Final examination scores were higher in 2008 grade than in 2007 grade.Based on the questionnaire survey,learning interests,sense of teamwork and classroom knowledge grasp of 2008 grade undergraduates were obviously elevated.Conclusions TBL teaching significantly improve students' learning effect and it can be promoted in stomotology education.