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1.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(10): 1692-1696, 2020 Oct 10.
Article in Chinese | MEDLINE | ID: mdl-33297628

ABSTRACT

Objective: To understand the etiological characteristics of an acute gastroenteritis outbreak. Methods: Real-time polymerase chain reaction (PCR) and bacteria cultures were performed for the samples, including stool samples from patients and cooks, environmental swabs, raw food material (chicken meat), collected during the outbreak. Pulsed-field gel electrophoresis, antibiotics susceptibility test and whole-genome sequencing were performed for the Campylobacter jejuni isolates. Results: Four stool samples from patients were positive for Campylobacter jejuni by real-time PCR, in which 1 Campylobacter jejuni strain was isolated from a case who had no antibiotic treatment. Twelve Campylobacter jejuni and 7 Campylobacter coli isolates were obtained from 4 raw chicken meat samples. The Campylobacter jejuni strain isolated from the case was resistant to nalidixic acid, ciprofloxacin, chloramphenicol, florfenicol and tetracycline. The MLST analysis with the whole-genome sequences confirmed that the Campylobacter jejuni isolate from the case belonged to ST10075. Antimicrobial resistance genes cmeABCR, tetO/M and blaOXA-61 were found in the genome of the isolate from the patient by the whole-genome sequencing. No mutation in 23S rRNA was found and the C257T mutation in gyrA was identified in this isolate. Conclusion: Laboratory analysis indicated that Campylobacter jejuni infection might be the major cause of this gastroenteritis outbreak.


Subject(s)
Campylobacter jejuni , Disease Outbreaks , Gastroenteritis , Laboratories , Animals , Anti-Bacterial Agents/pharmacology , Campylobacter jejuni/drug effects , Campylobacter jejuni/genetics , Campylobacter jejuni/isolation & purification , Chickens , China/epidemiology , Drug Resistance, Bacterial/genetics , Feces/microbiology , Gastroenteritis/epidemiology , Gastroenteritis/microbiology , Humans , Meat/microbiology , Multilocus Sequence Typing
2.
Zhonghua Zhong Liu Za Zhi ; 42(10): 861-867, 2020 Oct 23.
Article in Chinese | MEDLINE | ID: mdl-33113628

ABSTRACT

Objective: To evaluate the cost effectiveness of primary prophylaxis (PP) with pegylated recombinant human granulocyte colony stimulating factor (PEG-rhG-CSF), PP with recombinant human granulocyte colony stimulating factor (rhG-CSF) and no prophylaxis in women with early-stage breast cancer in China. Methods: Two phase Markov models were constructed for a hypothetical cohort of patients aged 45 with stage Ⅱ breast cancer. The first phase modelled costs and outcomes of 4 cycles docetaxel combined with cyclophosphamide [TC×4, febrile neutropenia (FN) risk>20%] chemotherapy, which assumptions based on literature reviews, including FN rates [base-case (deterministic sensitivity analysis range), 0.29 (0.24-0.35)] and related events [FN case-fatality, 3.4 (2.7-4.1)]. Second phase modelled the long term survival which was link with the relative dose intensity (RDI) [mortality hazard ratio (HR) of RDI < 85% vs ≥85%, 1.45 (1.00-2.32)]. Clinical effectiveness, therapeutic costs, and economic utilities were estimated from peer-reviewed publications and expert opinions in case of unavailability of published evidences. Results: Compared to rhG-CSF PP and no prophylaxis, the cost of PEG-rhG-CSF PP increased to 5 208.19 RMB and 5 222.73 RMB, respectively. The quality-adjusted life-years (QALYs) enhanced to 0.066 and 0.297, respectively. Accordingly, the incremental cost effectiveness ratios (ICERs) are 79 146.3 RMB and 17 558.77 RMB per QALY, which were both below the willingness to pay (WTP) threshold of three times GDP per capita (18, 000 RMB) recommended by the WHO. Sensitivity analysis suggested that the more clinically effective the primary prophylaxis with PEG-rhG-CSF is, the more cost-effective primary prophylaxis with PEG-rhG-CSF will be. And the lower the mortality HR of RDI<85% vs ≥85% is, the more cost-effective primary prophylaxis with PEG-rhG-CSF will be. Conclusion: Although the cost of PP PEG-rhG-CSF is higher, considering the additional benefits, the administrating of PP PEG-rhG-CSF is likely to be a cost-effective alternative to PP rhG-CSF and no prophylaxis in patients with early stage breast cancer whose FN risks are more than 20% in China.


Subject(s)
Breast Neoplasms , Febrile Neutropenia/prevention & control , Granulocyte Colony-Stimulating Factor/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Breast Neoplasms/economics , China , Cost-Benefit Analysis , Female , Granulocyte Colony-Stimulating Factor/economics , Humans , Markov Chains , Middle Aged , Recombinant Proteins/economics , Recombinant Proteins/therapeutic use
4.
Eur Rev Med Pharmacol Sci ; 23(3): 1055-1062, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30779072

ABSTRACT

OBJECTIVE: Hypoxia-inducible factor 1α (HIF-1α) functions importantly in the development of colorectal cancer. HIF-1α is induced by some cytokines and growth factors and is also regulated by another kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathways. Meanwhile, inhibiting HIF-1α expression can inhibit the development of colorectal cancer. The aim of this study was to explore the effect of epidermal growth factor (EGF) on the activation of signal transducer and activator of transcription 3 (STAT3) in human colorectal cancer cells SW480. In addition, the underlying mechanism of the STAT3 signaling pathway in regulating HIF-1α and further affecting tumorigenesis and metastasis was investigated. MATERIALS AND METHODS: Immunofluorescence and Western blotting were used to detect the activation of STAT3 by EGF in human colorectal cancer cells SW480. SW480 cells were transfected with STAT3 siRNA or treated with STAT3 inhibitor Niclosamide, and then stimulated with EGF to change the expressions of STAT3 and p-STAT3. The expression level of HIF-1α mRNA in SW480 cells was detected by Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). In addition, transwell assay and tumor formation experiments were performed to validate whether STAT3 and HIF-1α affected SW480 through EGF. RESULTS: STAT3 was not activated in SW480 cells in vitro. EGF induced STAT3 activation and enhanced its phosphorylation level, so that it shuttled into the nucleus. Phosphorylated activation of STAT3 was a necessary condition for EGF to induce HIF-1α up-regulation. Both HIF-1α and EGF-induced phosphorylation of STAT3 could significantly promote the proliferation and metastasis of SW480, and enhance tumorigenesis. CONCLUSIONS: In SW480 cells, EGF regulated HIF-1α through the STAT3 phosphorylation pathway, eventually promoting the occurrence and metastasis of colorectal cancer.


Subject(s)
Epidermal Growth Factor/physiology , Gene Expression Regulation, Neoplastic/physiology , Hypoxia-Inducible Factor 1, alpha Subunit/biosynthesis , STAT3 Transcription Factor/metabolism , Carcinogenesis/drug effects , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Epidermal Growth Factor/pharmacology , Humans , Niclosamide/pharmacology , Phosphorylation/physiology , RNA, Small Interfering/pharmacology , STAT3 Transcription Factor/antagonists & inhibitors , Signal Transduction/drug effects , Up-Regulation/drug effects
5.
Niger J Clin Pract ; 21(10): 1361-1367, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30297572

ABSTRACT

AIM: To explore the use of cancer-testis antigen G antigen 1 (GAGE-1) in the diagnosis and potential therapeutic targeting of hepatocellular carcinoma (HCC), we measured the expression of GAGE-1 protein levels in HCC tissues and its serum immunoreactivity in HCC patients. MATERIALS AND METHODS: We detected the expression of GAGE-1 protein in HCC by immunohistochemistry (IHC). We then analyzed the clinical significance of GAGE-1 expression in HCC with respect to clinicopathological parameters. We observed positive anti-GAGE-1 antibody reactivity in HCC patient serum, liver cirrhosis patients (LC), hepatitis B patients (HB), and normal human individuals (NHS) by enzyme-linked immunosorbent assay. RESULTS: The IHC results showed that the positive rates of GAGE-1 protein expression in cancer tissues and adjacent tissues were 43.3% (26/60) and 5% (3/60), respectively. The expression level of GAGE-1 protein in HCC tissues was significantly higher than that in tumor-adjacent tissues (P < 0.05). Positive GAGE-1 protein expression was not correlated with clinicopathological parameters (P > 0.05). Positive serum anti-GAGE-1 antibody reactivity in HCC patients, LC, HB, and NHS was 23.33% (14/59), 13.1% (8/61), 3.3% (2/60), and 3.4% (2/59), respectively. The frequency of anti-GAGE-1 antibody-positive sera in HCC patients and LC was significantly different than that in HB and NHS (P < 0.01), but no significant differences were found between HCC patients and LC (P = 0.485) or between HB and NHS (P = 0.410). Positive anti-GAGE-1 antibody reactivity was not correlated with clinicopathological parameters (P > 0.05). CONCLUSION: These data illustrate that the GAGE-1 protein exhibits moderate cancer-restricted pattern of expression and immunogenicity, laying the foundation for the application of GAGE-1 in immunotherapy and for the diagnosis of HCC.


Subject(s)
Antigens, Neoplasm/immunology , Antigens, Surface/blood , Autoantibodies/blood , Biomarkers, Tumor/blood , Carcinoma, Hepatocellular/diagnosis , Liver Neoplasms/diagnosis , Neoplasm Proteins/blood , Testis/pathology , Adult , Aged , Antigens, Neoplasm/blood , Antigens, Neoplasm/metabolism , Antigens, Surface/metabolism , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/immunology , Female , Humans , Immunohistochemistry , Liver Neoplasms/blood , Liver Neoplasms/immunology , Male , Middle Aged , Neoplasm Proteins/metabolism
6.
Eur Rev Med Pharmacol Sci ; 21(10): 2377-2384, 2017 05.
Article in English | MEDLINE | ID: mdl-28617552

ABSTRACT

OBJECTIVE: This paper aimed to investigate the effect of long non-coding RNA TUG1 (lncRNA TUG1) on cell proliferation, as well as cell migration in pancreatic cancer. PATIENTS AND METHODS: The mRNA levels of Taurine-up-regulated gene 1 (TUG1) in three kinds of pancreatic cancer cells BxPC3, PaTu8988 and SW1990 was detected by RT-qPCR. Meantime, RT-qPCR was used to examine the mRNA levels of TUG1 in 20 cases of human pancreatic cancer tissues and its para-carcinoma tissues. pCDH-TUG1 plasmid and its empty plasmid pCDH were transfected into BxPC3 and PaTu8988 cells to up-regulate TUG1 expression. siRNA targeting TUG1 and the control siRNA were transfected into SW1990 cells to down-regulate TUG1 expression. Cell clone formation and CCK-8 assay were used to detect the cell proliferation capacity. Transwell assay was used to evaluate cell migration capacity. Western blot was applied to examine the protein expressions of MMP2, MMP9, E-cadherin, Smad 2, Smad 3, p-Smad 2, p-Smad 3, TGF-ß and TGF-ßR. RT-qPCR was used to detect the levels of MMP2 and MMP9. RESULTS: The results showed that TUG1 was differentially expressed in the three kinds of pancreatic cancer cells, among which the expression level of SW1990 was relatively high, and the expression levels of BxPC3 and PaTu8988 were relatively low. TUG1 had more expression in pancreatic cancer tissues than that in para-carcinoma tissues. After the up-regulation of TUG1, cell proliferation and migration capacities were increased, protein levels of MMP2 and MMP9 were increased and protein level of E-cadherin was declined. Conversely, after down-regulation of TUG1 expression, cell proliferation and migration capacities were weakened, protein levels of MMP2 and MMP9 were decreased and protein level of E-cadherin was increased. In addition, over-expressed TUG1 could promote Smad2 and Smad3 phosphorylation, but Smad2 and Smad3 phosphorylation were weakened after down-regulated expression of TUG1. The protein expression of TGF-ß and TGF-ß receptor were more in the TUG1 overexpression group than that in the control group, while the result was just opposite after TUG1 expression was down-regulated. CONCLUSIONS: These data suggest that lncRNA TUG1 may enhance the proliferation and migration of pancreatic cancer cells through EMT pathway.


Subject(s)
Cadherins/genetics , Cell Movement/genetics , Cell Proliferation/genetics , Pancreatic Neoplasms/pathology , Protein Serine-Threonine Kinases/genetics , RNA, Long Noncoding/genetics , RNA, Messenger/genetics , RNA, Small Interfering/genetics , Receptors, Transforming Growth Factor beta/genetics , Smad2 Protein/genetics , Smad3 Protein/genetics , Antigens, CD , Cadherins/metabolism , Carcinoma , Cell Movement/physiology , Down-Regulation , Humans , RNA, Messenger/metabolism , Receptor, Transforming Growth Factor-beta Type II , Smad2 Protein/metabolism , Smad3 Protein/metabolism , Transfection , Transforming Growth Factor beta/genetics , Up-Regulation
7.
Genet Mol Res ; 14(2): 6369-75, 2015 Jun 11.
Article in English | MEDLINE | ID: mdl-26125841

ABSTRACT

Genotyping is a critical step for molecular marker-assisted selection in rice. Rice genomic DNA samples for genotyping are typically isolated from living tissues such as seedlings. This requires the germination of all candidate seeds and extraction of DNA from the seedlings. Currently, an ideal individual is selected from a very large number of plants, which is time- and labor-consuming, requiring several transplantations of materials and sampling processes. In this study, we developed a simplified genomic DNA extraction protocol in rice by using amylase to treat half-seeds. The yields of genomic DNA from a half-seed of Indica and Japonica rice were greater than 203.8 ± 32.5 and 143.2 ± 25.5 ng, respectively, and the 260/280 nm absorbance ratio was 1.75-2.10. The DNA was confirmed to be sufficient for polymerase chain reaction amplification and can be used in a marker-assisted selection program.


Subject(s)
DNA, Plant/isolation & purification , Genomics , Germination/genetics , Oryza/genetics , DNA, Plant/genetics , Genome, Plant , Genotype , Seedlings/genetics , Seeds/genetics
9.
J Int Med Res ; 40(3): 859-66, 2012.
Article in English | MEDLINE | ID: mdl-22906258

ABSTRACT

OBJECTIVE: Bone metastasis is a major complication of advanced breast cancer. The present prospective case-control study investigated the involvement of microRNA (miR)-10b in the development of bone metastasis arising from primary breast carcinoma. METHODS: Serum miR-10b concentrations were determined by quantitative real-time reverse transcription-polymerase chain reaction in 122 patients with breast cancer, with or without bone metastases, and 59 age-matched healthy control subjects. RESULTS: Serum miR-10b concentrations were significantly higher in patients with bone metastases than in patients without bone metastases or control subjects. Serum miR-10b had an area under the receiver operating characteristic curve for the presence of bone metastases of 0.769, with 64.8% sensitivity and 69.5% specificity. CONCLUSION: These results suggest that serum miR-10b may be a useful biomarker for the identification of bone metastatic breast cancer.


Subject(s)
Biomarkers, Tumor/blood , Bone Neoplasms/secondary , Breast Neoplasms/blood , MicroRNAs/blood , Adult , Aged , Base Sequence , Biomarkers, Tumor/genetics , Bone Neoplasms/blood , Breast Neoplasms/pathology , Case-Control Studies , DNA Primers , Female , Humans , MicroRNAs/genetics , Middle Aged , ROC Curve , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Sensitivity and Specificity
10.
Exp Clin Endocrinol Diabetes ; 120(6): 367-75, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22639397

ABSTRACT

OBJECTIVES: To date no consensus has been reached on whether to administer statin to patients with Polycystic Ovary Syndrome (PCOS) routinely. Therefore, we conduct a meta-analysis to synthesize the literatures regarding therapeutic effects of statins on PCOS. METHODS: A comprehensive literature search was performed using terms such as polycystic ovary syndrome, ovary polycystic disease, PCOS, hyperandrogaenemia; simvastatin, atorvastatin, lipidemic-modulating drugs, lipid lowering drugs, and testosterone; randomized controlled trials in the following bibliographic databases: Medline, Embase, Cochrane Controlled Trials Register. Identified reference lists were checked manually. RESULTS: In total, 4 RCTs were included. 3 of 4 studies were double-blinded while none reported whether of the data was analyzed using intention-to-treat analysis. Serum total testosterone and lipid profiles were included as investigation outcomes. Differences in reducing serum total testosterone were observed when comparing statin with placebo (Std MD= - 3.03, 95%CI - 5.85 ~ - 0.22, P=0.03) or statin + metformin with metformin (Std MD=- 1.07, 95%CI: - 2.06~ - 0.07, P=0.04). Heterogeneities were detected in both comparisons (I2=96% and 88% respectively). Meanwhile, statin was more effective than placebo in reducing LDL (WMD=- 0.87, 95%CI - 1.18~ - 0.55, P<0.0001), TC (WMD=- 1.23 95%CI - 1.35~ - 1.11, P<0.00001), TG (WMD= - 0.50, 95%CI - 0.73~ - 0.27, P<0.00001); and statin + metformin was more effective than metformin in lowering LDL (WMD= - 0.84, 95%CI: - 1.33 ~ - 0.354, P=0.0009), TC (WMD= - 1.28, 95%CI: - 1.47 ~ - 1.10, P<0.00001), and TG (WMD= - 0.27, 95%CI: - 0.36~ - 0.19, P<0.00001). Heterogeneities were detected during the meta-analysis. CONCLUSIONS: Statins can reduce the concentration of total testosterone, TC, TG and LDL. However, it cannot be concluded that statins have long-term benefit. A large-scale, randomized controlled study is needed to ascertain this uncertainty.


Subject(s)
Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Polycystic Ovary Syndrome/drug therapy , Randomized Controlled Trials as Topic/statistics & numerical data , Algorithms , Double-Blind Method , Female , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/administration & dosage , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/pharmacology , Hypolipidemic Agents/administration & dosage , Hypolipidemic Agents/therapeutic use , Metformin/administration & dosage , Metformin/pharmacology , Placebos , Polycystic Ovary Syndrome/epidemiology , Treatment Outcome
11.
J Fish Biol ; 78(4): 1225-38, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21463317

ABSTRACT

Three full-length complementary DNA (cDNA) clones were isolated encoding the skeletal myosin light chain 1 (MLC1; 1237 bp), myosin light chain 2 (MLC2; 1206 bp) and myosin light chain 3 (MLC3; 1079 bp) from the fast white muscle cDNA library of mandarin fish Siniperca chuatsi. The sequence analysis indicated that MLC1 and MLC3 were not produced from differentially spliced messenger RNAs (mRNA) as reported in birds and rodents but were encoded by different genes. The MLC2 encodes 170 amino acids, which include four EF-hand (helix-loop-helix) structures. The primary structures of the Ca(2+)-binding domain were well conserved among the MLC2s of seven other fish species. The ontogenetic expression analysis by real-time PCR showed that the three light-chain mRNAs were first detected in the gastrula stage, and their expression increased from the tail bud stage to the larval stage. All three MLC mRNAs showed longitudinal expression variation in the fast white muscle of S. chuatsi, especially MLC1 which was highly expressed at the posterior area. Taken together, the study provides a better understanding about the MLC gene structure and their expression pattern in muscle development of S. chuatsi.


Subject(s)
Gene Expression Regulation, Developmental , Muscle Fibers, Fast-Twitch/metabolism , Myosin Light Chains/metabolism , Perciformes/genetics , Perciformes/metabolism , Amino Acid Sequence , Animals , Base Sequence , Molecular Sequence Data , Myosin Light Chains/chemistry , Myosin Light Chains/genetics , Perciformes/classification , Phylogeny , Sequence Alignment
13.
Neuroscience ; 130(1): 229-38, 2005.
Article in English | MEDLINE | ID: mdl-15561439

ABSTRACT

Taste receptor cells are primary sensory receptors utilized by the nervous system to detect the presence of gustatory stimuli in the oral cavity. These cells are particularly heterogeneous and may be divided into various subtypes based on morphological, histochemical, or physiological criteria. One example is the heterogeneous expression of neuropeptides, such as cholecystokinin and vasoactive intestinal polypeptide. These peptides are hypothesized to participate in the transduction processes. To pursue examination of this hypothesis, this study explored the relationship of peptide expression with two important and mostly non-overlapping transductive elements--the taste-specific G protein gustducin, involved in bitter and sweet transduction cascades, and the seven transmembrane taste receptor T1R2, hypothesized to respond to sweet compounds. Double labeling experiments were performed on taste buds of the posterior rat tongue combining immunocytochemistry for peptide expression and in situ hybridization experiments for either gustducin or T1R2 expression. Additionally, vasoactive intestinal peptide (VIP)-expression in posterior taste receptor cells was confirmed using the technique of RT-PCR. More than half (56%) of the CCK-expressing taste receptor cells co-expressed alpha-gustducin mRNA whereas far fewer (15%) co-expressed T1R2 mRNA. A majority of VIP-expressing taste receptor cells co-expressed alpha-gustducin mRNA (60%) whereas only 19% of these cells co-expressed T1R2 mRNA. More remarkable was the observation that these two peptides displayed almost identical expression patterns with these signal transduction molecules, suggesting that peptides are not randomly expressed with relation to signal transduction molecules. This observation supports the hypothesis that peptides may play roles in transduction. Further physiological exploration will be required to elucidate the nature of these roles.


Subject(s)
Cholecystokinin/metabolism , Neurons/metabolism , Taste Buds/cytology , Transducin/metabolism , Vasoactive Intestinal Peptide/metabolism , Animals , Cell Count , Cholecystokinin/genetics , Gene Expression Regulation/physiology , Immunohistochemistry/methods , In Situ Hybridization/methods , Male , Neurons/classification , RNA, Messenger/biosynthesis , Rats , Rats, Sprague-Dawley , Receptors, G-Protein-Coupled/genetics , Receptors, G-Protein-Coupled/metabolism , Reverse Transcriptase Polymerase Chain Reaction/methods
14.
Ultramicroscopy ; 95(1-4): 75-80, 2003.
Article in English | MEDLINE | ID: mdl-12535547

ABSTRACT

A model for field emission through an amorphous diamond thin film with defects is constructed. Theoretical study shows that the emission is enhanced by attractive defects which would make the resonant emission observable for films with thickness of about 10nm. The emitted current density in typical parameters is calculated as functions of thickness, field strength and defect density. The energy distribution of emitted electrons is attained.

15.
Talanta ; 54(2): 333-42, 2001 Apr 12.
Article in English | MEDLINE | ID: mdl-18968256

ABSTRACT

The mixture of concanavalin A (Con A) and glycogen shows strong light scattering character. Based on it, the interaction between Con A and glycogen was studied on a common spectrofluorimeter by light scattering technique. Many factors affecting the light scattering intensity (LSI), such as pH, temperature, reaction time, ion strength and the denaturing agent of protein were studied in detail. Experimental results showed that the LSI reached its maximum after mixing Con A with glycogen for about 20 min in pH 7.4 Tris-HCl buffer at 37 degrees C. The results also suggested that the conformation of Con A was critical for its unique binding affinity to glycogen. Electrostatic forces should not be the primary interaction between glycogen and Con A. Under proper experimental conditions, the determination method for glycogen by light scattering technique was developed. The glycogen determination can be performed in the range of 0.48-32.0, 0.50-32.0 and 0.32-24.0 mug/ml for Rabbit liver glycogen (RL Gly), Oyster glycogen (O Gly) and Clam Glycogen (C Gly), respectively. The influence of co-existing substances such as proteins, mono- and di-saccharides and metal ions was evaluated, and little interference came from the foreign substances. The determinations of glycogen in synthetic samples demonstrated that the recovery rate was in the range of 98.1-103% and the relative standard deviations (RSD) were lower than 5.0%.

16.
Spectrochim Acta A Mol Biomol Spectrosc ; 56A(9): 1827-33, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10952145

ABSTRACT

The interaction of brilliant cresol blue (BCB) with nucleic acids in aqueous solution has been studied by spectrophotometry and Rayleigh light scattering (RLS) spectroscopy. Under suitable conditions, the RLS spectra of BCB changed significantly due to the presence of nucleic acids. RLS intensity of BCB at 364 nm is greatly enhanced with the addition of nucleic acids, and a new RLS peak is observed at 552 nm. This peak is about half the intensity of that at 364 nm. The results of this study show that BCB interacts with DNA possibly due to the cooperative effect of electrostatic attraction, intercalation, coordination and hydrophobic effect. Under optimum conditions, the increase of RLS at 364 nm of a BCB solution is proportional to the concentration of nucleic acids added. This result is the basis for a new RLS method for determination of nucleic acids. The linear range of ctDNA, fsDNA and yRNA is 0.12-4.70, 0.11-4.64 and 0.43-7.07 microg ml(-1), respectively.


Subject(s)
Nucleic Acids/chemistry , Oxazines/chemistry , Spectrophotometry, Atomic/methods , Hydrogen-Ion Concentration , Osmolar Concentration , Solvents/chemistry , Surface-Active Agents/chemistry
17.
Se Pu ; 18(2): 152-4, 2000 Mar.
Article in Chinese | MEDLINE | ID: mdl-12541594

ABSTRACT

A high performance capillary zone electrophoretic method has been developed for the separation of proteins in human serum. Sera were diluted with a buffer (0.05 mol/L boric acid, pH 8.80), and then introduced hydrodynamically into a 37 cm (32 cm to detector) x 50 microns i.d. fused-silica capillary, electrophoresed for 12 min using a boric buffer solution (0.10 mol/L, pH 9.35; containing 4 g/L of polyethylene glycol 8000), and detected at the wavelength of 200 nm. The method is simple, rapid and repeatable.


Subject(s)
Electrophoresis, Capillary/methods , Serum Albumin/isolation & purification , Alpha-Globulins/analysis , Humans , gamma-Globulins/analysis
18.
Biomed Chromatogr ; 12(6): 326-9, 1998.
Article in English | MEDLINE | ID: mdl-9861491

ABSTRACT

A simple and sensitive reversed-phase liquid chromatographic method has been developed and validated for the analysis of nicardipine in human plasma and the study of the pharmacokinetics of the drug in human body. Nicardipine and nimodipine (internal standard) in plasma were extracted with hexane-butanol (12:1, v/v) after addition of borate buffer (0.5 mol/mL, pH = 9.0), and then measured by HPLC using a Hypersil C18 column as stationary phase and acetonitrile--KH2PO4 buffer (0.015 M, pH = 5.5)--triethylamine as mobile phase. Nicardipine was quantified by ultraviolet absorbance at 236 nm. The method proved to be linear in the clinical range of 5-200 ng/mL with a regression coefficient of 0.9998. The lower limit of detection of nicardipine in plasma was 2.5 ng/mL. Intra- and inter-day coefficients of variation of assay for nicardipine in plasma were 3.5-5.4% (n = 7) and 5.2-6.4% (n = 5), respectively. The recovery of nicardipine was 92.8-100.8% for plasma. The method has been used to determine nicardipine in plasma samples from 10 volunteers and provided data on the pharmacokinetics of the drug. The results inferred that nicardipine is absorbed rapidly and has a relatively short half-life in healthy individuals. The data obtained was fitted with a 3P87 program to study the pharmacokinetics. The results showed that the disposition of nicardipine was conformed to a two-compartment open model with Tmax = 1.6 +/- 0.3 h, Cmax = 109.8 +/- 38.7 ng/mL, T1/2 = 5.35 +/- 2.28 h and AUC0-->infinity = 322.1 +/- 69.6 ng/h/mI.


Subject(s)
Calcium Channel Blockers/blood , Chromatography, High Pressure Liquid/methods , Nicardipine/blood , Adult , Calcium Channel Blockers/pharmacokinetics , Humans , Male , Nicardipine/pharmacokinetics , Nimodipine/blood , Nimodipine/pharmacokinetics , Reference Standards , Spectrophotometry, Ultraviolet
19.
Opt Lett ; 23(10): 777-9, 1998 May 15.
Article in English | MEDLINE | ID: mdl-18087339

ABSTRACT

The spectral and temporal emission properties of a Rhodamine (Rh) dye solution embedded with nanoparticle fractal aggregates are studied. An experiment on the pump-power density dependence of Rh emission spectra shows that the lasing threshold of a Rh6G solution embedded with TiO(2) nanoparticle fractal aggregates is significantly reduced compared with that of a neat dye solution. The mechanism of this reduction in lasing threshold is discussed, together with the lasing properties of narrow bandwidth and short duration.

20.
Yao Xue Xue Bao ; 32(11): 857-60, 1997 Nov.
Article in Chinese | MEDLINE | ID: mdl-11596205

ABSTRACT

A reversed phase high performance liquid chromatographic method utilizing solid phase extraction has been described for the determination of enalapril in human plasma. The C18 sorbent cartridges were conditioned and plasma samples were applied, washed with 20 mmol.L-1 HCl (2 x 0.5 ml) and petroleum ether (boiling range 60-90 degrees C) subsequently; and eluted with methanol (3 x 0.5 ml). The eluent was evaporated to dryness, reconstituted in 100 microliters mobile phase and injected. Chromatographic separation was achieved on a Spherisorb C8 column (200 mm x 4.6 mm, 5 microns), with ethanol--water--10% H3PO4--triethylamine (30:70:1.5:0.1) at a flow rate of 1.0 ml.min-1. UV detection was set at 215 nm. The calibration ranges were 2.5-150 ng.ml-1 with regression coefficient of 0.997 and detection limit of 1.5 ng.ml-1. The within-day RSD and between-day RSD were < 8.73%, the recovery of method > 91.6%. This method was applied to the pharmacokinetic analysis of enalapril in 8 human volunteers.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/blood , Antihypertensive Agents/blood , Enalapril/blood , Angiotensin-Converting Enzyme Inhibitors/pharmacokinetics , Antihypertensive Agents/pharmacokinetics , Area Under Curve , Enalapril/pharmacokinetics , Humans , Male
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