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1.
Biol Trace Elem Res ; 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38514508

ABSTRACT

Despite the robust correlation between metabolic disorders and heavy metals, there has been limited research on the associations between nickel levels and non-alcoholic fatty liver disease (NAFLD) as well as liver fibrosis. This study aimed to examine the associations among urinary nickel, NAFLD, and liver fibrosis. The data utilized in this study were obtained from the National Health and Nutrition Examination Survey 2017-2020. A comprehensive screening process was conducted, resulting in the inclusion of a total of 3169 American adults in the analysis. The measurement of urinary nickel was conducted through inductively coupled-plasma mass spectrometry. Vibration-controlled transient elastography was employed to assess the controlled attenuation parameter and liver stiffness measurement as indicators for NAFLD and liver fibrosis, respectively. Multivariable logistic regression models were employed to evaluate the associations among urinary nickel, NAFLD, and liver fibrosis. Restricted cubic splines were employed to explored the nonlinear associations. After adjusting for all covariates, the correlation between the highest quartile of urinary nickel and NAFLD was found to be significant (OR = 1.65; 95% CI, 1.19-2.27). Subgroup analysis revealed that the correlation was significant only in men. A significant association occurred between the second quartile of urinary nickel and liver fibrosis (OR 1.88; 95% CI, 1.22-2.90). Restricted cubic spline showed that the relationship was linear between urinary nickel and NAFLD and non-monotonic, inverse U-shaped between urinary nickel and liver fibrosis. This cross-sectional study indicated that the risk of NAFLD is associated with urinary nickel, and this correlation was only present among males.

2.
Nutrients ; 15(21)2023 Oct 31.
Article in English | MEDLINE | ID: mdl-37960269

ABSTRACT

The etiology of numerous metabolic disorders is characterized by hepatic insulin resistance (IR). Uncertainty surrounds miR-34a's contribution to high-fat-induced hepatic IR and its probable mechanism. The role and mechanism of miR-34a and its target gene ENO3 in high-fat-induced hepatic IR were explored by overexpressing/suppressing miR-34a and ENO3 levels in in vivo and in vitro experiments. Moreover, as a human hepatic IR model, the miR-34a/ENO3 pathway was validated in patients with non-alcoholic fatty liver disease (NAFLD). The overexpression of hepatic miR-34a lowered insulin signaling and altered glucose metabolism in hepatocytes. In contrast, reducing miR-34a expression significantly reversed hepatic IR indices induced by palmitic acid (PA)/HFD. ENO3 was identified as a direct target gene of miR-34a. Overexpression of ENO3 effectively inhibited high-fat-induced hepatic IR-related indices both in vitro and in vivo. Moreover, the expression patterns of members of the miR-34a/ENO3 pathway in the liver tissues of NAFLD patients was in line with the findings of both cellular and animal studies. A high-fat-induced increase in hepatic miR-34a levels attenuates insulin signaling and impairs glucose metabolism by suppressing the expression of its target gene ENO3, ultimately leading to hepatic IR. The miR-34a/ENO3 pathway may be a potential therapeutic target for hepatic IR and related metabolic diseases.


Subject(s)
Insulin Resistance , MicroRNAs , Non-alcoholic Fatty Liver Disease , Animals , Humans , Mice , Non-alcoholic Fatty Liver Disease/genetics , Non-alcoholic Fatty Liver Disease/drug therapy , MicroRNAs/genetics , MicroRNAs/metabolism , Liver/metabolism , Insulin/metabolism , Glucose/metabolism , Mice, Inbred C57BL
3.
Cancer Med ; 12(1): 223-235, 2023 01.
Article in English | MEDLINE | ID: mdl-35674137

ABSTRACT

BACKGROUND: Induction chemotherapy (IC) comprising docetaxel, cisplatin, and fluorouracil (TPF), combined with concurrent chemoradiotherapy (CCRT) effectively improves the survival rate of locally advanced nasopharyngeal carcinoma (LA-NPC). Selecting patients whose risk of tumor recurrence and metastasis is high and the appropriate chemotherapy intensity is a concern. We combined tumor-node-metastasis staging with the load of Epstein-Barr virus (EBV) after IC to select the individualized chemotherapy strength. METHODS: The clinical data and prognostic factors of patients with stage III-IV LA-NPC treated with TPF IC combined with CCRT were analyzed retrospectively. The conventional treatment group received the standard three cycles TPF IC combined with CCRT. For the new treatment group, the cycles of IC were determined according to whether the EBV-DNA disappeared completely after a certain course of IC, if so, subsequent IC was stopped and the chemoradiotherapy stage was entered. Propensity score matching (PSM) was performed at a ratio of 1:1 to balance baseline characteristics. Survival outcomes and adverse events between the conventional treatment group and the new method treatment group were compared. RESULTS: The study included 256 patients, among whom 192 were matched successfully into 96 pairs. The patients were followed up for a median of 51 months. The proportions of patients receiving three, two, and one cycle of IC after PSM in the routine and new treatment cohorts were 93.8%, 3.1%, 3.1% versus 21.9%, 49.0%, 24.0%, respectively. However, their 3-year distant metastasis-free survival, local recurrence-free survival, progression-free survival, and overall survival did not differ significantly. The incidence of grade 3-4 neutropenia toxicity in CCRT decreased significantly in patients receiving the new treatment method compared with that in the conventional treatment group (p = 0.026). CONCLUSION: Combining TNM stage and EBV-DNA load after IC to determine the courses of IC in patients with LA-NPC did not alter the curative effect but decreased toxicity.


Subject(s)
Carcinoma , Epstein-Barr Virus Infections , Nasopharyngeal Neoplasms , Neutropenia , Humans , Nasopharyngeal Carcinoma/drug therapy , Nasopharyngeal Carcinoma/pathology , Herpesvirus 4, Human/genetics , Induction Chemotherapy/adverse effects , Nasopharyngeal Neoplasms/drug therapy , Nasopharyngeal Neoplasms/pathology , Retrospective Studies , Epstein-Barr Virus Infections/complications , Epstein-Barr Virus Infections/drug therapy , Neoplasm Recurrence, Local/drug therapy , Carcinoma/complications , Neutropenia/etiology , Chemoradiotherapy/methods , DNA/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects
5.
Front Pharmacol ; 12: 688528, 2021.
Article in English | MEDLINE | ID: mdl-34621166

ABSTRACT

Objective: This study aims to compare the treatment outcomes of concurrent chemoradiotherapy (CCRT) versus radiotherapy (RT) alone in stage II nasopharyngeal carcinoma (NPC) patients. Methods: We retrospectively collected 601 stage II NPC patients treated in two hospitals between June 2003 to June 2016. All patients were divided into the CCRT group (n = 255) and the RT group (n = 346). Overall survival (OS), locoregional failure-free survival (LRFFS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) were assessed using the Kaplan-Meier method. The log-rank test was used to compare the differences between the groups. The Cox-regression hazards model was performed to determine potential prognostic factors. Results: The median follow-up was 99 months. No significant difference was found in locoregional recurrence, distant metastasis, disease progression, and death between the two groups (all p > 0.05). In univariate analysis, the 5-years OS, PFS, LRFFS, and DMFS had no significant differences between the CCRT and RT groups (all p > 0.05). Two-dimensional radiotherapy (2DRT) sub-analysis showed that CCRT remarkably increased DMFS, PFS, and OS rates (all p < 0.05) but not LRFFS (p = 0.258) compared with RT alone. While intensity-modulated radiotherapy (IMRT) sub-analysis showed that the prognosis of the two groups had no significant differences (all p > 0.05). In multivariate analyses, age was significantly and inversely related to OS, PFS, LRFFS, and DMFS. IMRT was an independent favorable factor for improving LRFFS, PFS, and OS. Concurrent chemotherapy was an independent protective factor for DMFS. Conclusion: In the context of 2DRT, it is definite that concurrent chemotherapy provides survival benefits for patients with stage II NPC. While in the IMRT era, the impact of chemotherapy on survival in patients with stage II NPC is weakened. Prospective randomized controlled studies are required to confirm these results.

6.
ACS Omega ; 6(5): 3946-3950, 2021 Feb 09.
Article in English | MEDLINE | ID: mdl-33644531

ABSTRACT

Room-temperature superconductivity has always been an area of intensive research. Recent findings of clathrate metal hydrides structures have opened up the doors for achieving room-temperature superconductivity in these materials. Here, we report first-principles calculations for stable H-rich clathrate structures of uranium hydrides at high pressures. The clathrate uranium hydrides contain H cages with stoichiometries of H24, H29, and H32, in which H atoms are bonded covalently to other H atoms, and U atoms occupy the centers of the cages. Especially, a UH10 clathrate structure containing H32 cages is predicted to have an estimated T c higher than 77 K at high pressures.

7.
Ophthalmic Plast Reconstr Surg ; 36(6): 617-620, 2020.
Article in English | MEDLINE | ID: mdl-32251174

ABSTRACT

PURPOSE: An anatomical and histological study of the conjoint fascial sheath of the levator and superior rectus (CFS) was carried out by using the cadavers for teaching. METHODS: Three adult Asian cadaver heads fixed in formalin were used. The CFS was exposed by the same surgeon in each case. Then the CFS was observed and measured in vivo and ex vivo. And the CFS, the levator and the frontal muscle were removed from the same eye for histological study. RESULTS: The CFS was located 2.1 ± 0.4 mm posterior to the fornix. A special muscle sheath of the levator was observed. The special muscle sheath and the tendon of the superior rectus were fused to the CFS through loose connective tissue. Hematoxylin-Eosin (HE) staining showed a large amount of connective tissue on examination of the CFS by microscopy. Double staining with Victoria-blue and Masson trichrome staining confirmed elastic fibers and collagen fibers in the CFS tissues. CONCLUSIONS: If ptosis correction surgery is performed by looking for the CFS from the upper edge of the conjunctiva, in fact, only a special part of the muscle sheath of the levator in the CFS, but not the integral CFS, is used in the surgery. The histological results confirm that the CFS is a fibrous tissue membrane with both elasticity and toughness. Perhaps the best choice is to recombine the special muscle sheath of the levator in the CFS with the levator muscle tissue during ptosis correction surgery to suspend the eyelids.


Subject(s)
Blepharoplasty , Blepharoptosis , Adult , Blepharoptosis/surgery , Eyelids/surgery , Fascia , Humans , Oculomotor Muscles/surgery
8.
J Zhejiang Univ Sci B ; 20(3): 219-237, 2019.
Article in English | MEDLINE | ID: mdl-30829010

ABSTRACT

BACKGROUND: Bone marrow-derived mesenchymal stem cells (BM-MSCs) play an important role in cancer development and progression. However, the mechanism by which they enhance the chemoresistance of ovarian cancer is unknown. METHODS: Conditioned media of BM-MSCs (BM-MSC-CM) were analyzed using a technique based on microRNA arrays. The most highly expressed microRNAs were selected for testing their effects on glycolysis and chemoresistance in SKOV3 and COC1 ovarian cancer cells. The targeted gene and related signaling pathway were investigated using in silico analysis and in vitro cancer cell models. Kaplan-Merier survival analysis was performed on a population of 59 patients enrolled to analyze the clinical significance of microRNA findings in the prognosis of ovarian cancer. RESULTS: MiR-1180 was the most abundant microRNA detected in BM-MSC-CM, which simultaneously induces glycolysis and chemoresistance (against cisplatin) in ovarian cancer cells. The secreted frizzled-related protein 1 (SFRP1) gene was identified as a major target of miR-1180. The overexpression of miR-1180 led to the activation of Wnt signaling and its downstream components, namely Wnt5a, ß-catenin, c-Myc, and CyclinD1, which are responsible for glycolysis-induced chemoresistance. The miR-1180 level was inversely correlated with SFRP1 mRNA expression in ovarian cancer tissue. The overexpressed miR-1180 was associated with a poor prognosis for the long-term (96-month) survival of ovarian cancer patients. CONCLUSIONS: BM-MSCs enhance the chemoresistance of ovarian cancer by releasing miR-1180. The released miR-1180 activates the Wnt signaling pathway in cancer cells by targeting SFRP1. The enhanced Wnt signaling upregulates the glycolytic level (i.e. Warburg effect), which reinforces the chemoresistance property of ovarian cancer cells.


Subject(s)
Drug Resistance, Neoplasm/genetics , Mesenchymal Stem Cells/cytology , MicroRNAs/genetics , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/genetics , Wnt Signaling Pathway , Adenosine Triphosphate/chemistry , Adult , Aged , Bone Marrow Cells/cytology , Cell Line, Tumor , Cell Proliferation , Cells, Cultured , Female , Flow Cytometry , Follow-Up Studies , Glycolysis , Humans , Intercellular Signaling Peptides and Proteins/metabolism , Membrane Proteins/metabolism , Middle Aged , Multivariate Analysis , Up-Regulation
9.
Huan Jing Ke Xue ; 39(4): 1782-1793, 2018 Apr 08.
Article in Chinese | MEDLINE | ID: mdl-29965005

ABSTRACT

In this paper, the performance, characteristics of the bulking sludge, and the variations in the microbial community (including the bulking bacteria) under different nitrogen and phosphorus imbalances were compared, using high-throughput sequencing (16S rRNA) and the high performance liquid chromatography (HPLC) technology. The results showed that after seeding bulking sludge in the A/O process and operating for a period of time, the sludge settleability of the nitrogen limitation alone reactor (RN) could recover to normal[sludge volume index (SVI)<150 mL·g-1], while the SVI of the phosphorus limitation alone reactor (RP) improved slightly; the control reactor (R0, C/N/P=100/5/1) exhibited the highest SVI index (SVI=1496 mL·g-1), followed by the reactor of simultaneous nitrogen and phosphorus limitations (RNP). Under normal nutritional conditions, Pearson correlation analysis showed a significant negative correlation between the lipopolysaccharide (LPS) relative content (LPS/MLVSS) and the settleability of bulking sludge (r=-0.625, P<0.05), while under nutrient limitation conditions, LPS showed high accuracy in reflecting the biomass of the activated sludge. Thiothrix was the dominant bulking bacteria in all the reactors. PCoA analysis showed that the migration of the community in the reactors experienced nitrogen limitation (RNP, RN) changes greatly during the stages Ⅱ and Ⅲ, while RDA analysis showed that the correlation of Thiothrix with the settling performance and oxygen consumption rate was significant.


Subject(s)
Bacteria/classification , Bioreactors/microbiology , Nitrogen/chemistry , Phosphorus/chemistry , Sewage/microbiology , Bacteria/metabolism , RNA, Ribosomal, 16S/genetics , Waste Disposal, Fluid
10.
Yao Xue Xue Bao ; 49(8): 1188-93, 2014 Aug.
Article in Chinese | MEDLINE | ID: mdl-25322563

ABSTRACT

Pluronic modified polyamidoamine (PAMAM) conjugate (PF127-PAMAM) was prepared and the inhibiting effect of MDR against MCF-7/ADR was investigated with doxorubicin (DOX) as model drug. 1H NMR and FTIR spectra showed that the conjugate was synthesized successfully. Element analysis accurately measured that 27.63% amino of per PAMAM was modified by pluronic (PAMAM : PF127, 1 : 35.37 mole ratio). PF127-PAMAM showed an increased size and a reduced zeta potential compared to PAMAM. PF127-PAMAM had lower hemolytic toxicity and cytotoxicity due to the reduced zeta potential and the protection of PF127. Each PF127-PAMAM molecular could load 19.58 DOX molecules, and the complex exhibited sustained and pH-sensitive release behavior. PF127-PAMAM/DOX exhibited weaker cytotoxicity than free DOX in MCF-7 cells; while the complex showed much stronger reverse effect of drug resistance in MCF-7/ADR cells, and resistance reversion index (RRI) was as high as 33.15.


Subject(s)
Dendrimers/pharmacology , Doxorubicin/pharmacology , Poloxamer/pharmacology , Humans , MCF-7 Cells/drug effects
11.
Zhonghua Yu Fang Yi Xue Za Zhi ; 47(1): 63-6, 2013 Jan.
Article in Chinese | MEDLINE | ID: mdl-23601526

ABSTRACT

OBJECTIVE: To develop a new transmission tracking analysis technique during incubation period of respiratory infectious diseases, and to discuss its practical value in the field survey of infectious diseases. METHODS: The classical epidemiological theory was integrated with geographic information system. The transmission tracking analysis technique was established based on the modeling platform ArcGIS Engine Developer Kit 9.3, using the techniques of address matching, shortest path analysis and buffer analysis, and programming by Visual C++. Eight serious sever acute respiratory syndrome (SARS) cases in Shanghai in year 2003 were then chose as prototype to set up the test cases A-H. The electronic map and population density data were separately collected from Institute of Surveying and Mapping in Shanghai and Shanghai statistical yearbook 2003, to calculate and explore the parameters as length of transmission path, area of buffer zone and key departments by single and multi case analysis module. RESULTS: The single case transmission tracking analysis showed that the length of transmission track of case A was 129.89 km during April 25th to 29th in 2003, including 12 tracing point and 108 intimate contacts, and the total area of buffer zone was 7.11 km(2) including 81 important institutes, naming 72 schools, 6 kindergartens and 3 gerocomiums. The multi-case transmission tracking analysis showed that the 8 cases shared 5 tracks without any temporal communication. However, there was a spatial communication whose length was 1.42 km and area was 0.60 km(2). There were no important institutes found in this communication area. CONCLUSION: Transmission tracking technique is practicable and efficient to trace the source of infection, analyze the transmission tracks, establish the isolation buffer area and explore the important geographic positions in epidemiological investigation.


Subject(s)
Contact Tracing/methods , Disease Transmission, Infectious/statistics & numerical data , Epidemiological Monitoring , Infectious Disease Incubation Period , Respiratory Tract Infections/transmission , Geographic Information Systems , Humans , Severe Acute Respiratory Syndrome/transmission , Software
12.
PLoS One ; 7(2): e31644, 2012.
Article in English | MEDLINE | ID: mdl-22384047

ABSTRACT

BACKGROUND: Clinical research indicates that periconceptional administration of folic acid can reduce the occurrence of congenital cardiac septal defects (CCSDs). The vital roles of folate exhibits in three ways: the unique methyl donor for DNA expression regulation, the de novo biosynthesis of purine and pyrimidine for DNA construction, and the serum homocysteine removal. Thymidylate synthase (TYMS) is the solo catalysis enzyme for the de novo synthesis of dTMP, which is the essential precursor of DNA biosynthesis and repair process. To examine the role of TYMS in Congenital Cardiac Septal Defects (CCSDs) risk, we investigated whether genetic polymorphisms in the TYMS gene associated with the CCSDs in a Han Chinese population. METHOD: Polymorphisms in the noncoding region of TYMS were identified via direct sequencing in 32 unrelated individuals composed of half CCSDs and half control subjects. Nine SNPs and two insertion/deletion polymorphisms were genotyped from two independent case-control studies involving a total of 529 CCSDs patients and 876 healthy control participants. The associations were examined by both single polymorphism and haplotype tests using logistic regression. RESULT: We found that TYMS polymorphisms were not related to the altered CCSDs risk, and even to the changed risk of VSDs subgroup, when tested in both studied groups separately or in combination. In the haplotype analysis, there were no haplotypes significantly associated with risks for CCSDs either. CONCLUSION: Our results show no association between common genetic polymorphisms of the regulatory region of the TYMS gene and CCSDs in the Han Chinese population.


Subject(s)
Heart Septal Defects/ethnology , Heart Septal Defects/genetics , Polymorphism, Genetic , Thymidylate Synthase/genetics , Case-Control Studies , Catalysis , Child , Child, Preschool , China , DNA/metabolism , Female , Gene Expression Regulation , Genetic Variation , Homocysteine/blood , Humans , Male , Polymorphism, Single Nucleotide , Purines/chemistry , Pyrimidines/chemistry
13.
Circulation ; 125(3): 482-90, 2012 Jan 24.
Article in English | MEDLINE | ID: mdl-22179537

ABSTRACT

BACKGROUND: Homocysteine is known to be an independent risk factor for congenital heart disease (CHD). Methionine synthase reductase (MTRR) is essential for the adequate remethylation of homocysteine, which is the dominant pathway for homocysteine removal during early embryonic development. METHODS AND RESULTS: Here, we report that the c.56+781 A>C (rs326119) variant of intron-1 of MTRR significantly increases the risk of CHD in the Han Chinese population. In 3 independent case-control studies involving a total of 2340 CHD patients and 2270 healthy control participants from different geographic areas, we observed that patients carrying the heterozygous AC and homozygous CC genotype had a 1.40-fold (odds ratio=1.40; P=2.32×10(-7)) and 1.84-fold (odds ratio=1.84; P=2.3×10(-11)) increased risk, respectively, of developing CHD than those carrying the wild-type AA genotype. Both in vivo quantitative real-time polymerase chain reaction analysis of MTRR mRNA in cardiac tissue samples from CHD patients and in vitro luciferase assays in transfected cells demonstrated that the c.56+781 C allele profoundly decreased MTRR transcription. Further analysis demonstrated that the c.56+781 C allele manifested reduced CCAAT/enhancer binding protein-α binding affinity. In addition, healthy individuals with the homozygous CC genotype had significantly elevated levels of plasma homocysteine compared with the wild-type AA carriers. CONCLUSIONS: We have demonstrated that the MTRR c.56+781 A>C variant is an important genetic marker for increased CHD risk because this variant results in functionally reduced MTRR expression at the transcriptional level. Our results accentuate the significance of functional single-nucleotide polymorphisms in noncoding regions of the homocysteine/folate metabolism pathway core genes for their potential contributions to the origin of CHD.


Subject(s)
Asian People/genetics , Asian People/statistics & numerical data , Ferredoxin-NADP Reductase/genetics , Heart Septal Defects/ethnology , Heart Septal Defects/genetics , Adult , Animals , Case-Control Studies , Cells, Cultured , Child , China/epidemiology , Ferredoxin-NADP Reductase/metabolism , Genetic Variation , Genotype , HEK293 Cells , Heart Septal Defects/metabolism , Homocysteine/blood , Humans , Introns/genetics , Myocytes, Cardiac/cytology , Polymorphism, Single Nucleotide/genetics , Rats , Risk Factors , Transcriptional Activation/genetics
14.
Carbohydr Res ; 345(18): 2670-5, 2010 Dec 10.
Article in English | MEDLINE | ID: mdl-20971449

ABSTRACT

Supramolecuar aggregations 1 and 2 were prepared by complexing cyclomaltohexaose with two azodipyridine isomers: 4,4'-azodipyridine and 2,2'-azodipyridine, and their binding abilities and assembly behaviors were investigated comprehensively by X-ray crystallography, 2D NMR spectroscopy, and isothermal titration calorimetry. In solution, 1:1 host-guest complexation is generally assumed, whereas in the solid state, a 2:1 stoichiometry is observed. Crystal structures reveal that channel-type aggregation exists in complex 1, while a layer-type manner is the dominant packing mode in complex 2. The disparity of nitrogen atom position leads to the different binding modes and further affects the aggregation types in complexes 1 and 2.


Subject(s)
alpha-Cyclodextrins/chemistry , Crystallography, X-Ray , Magnetic Resonance Spectroscopy , Models, Molecular , Solutions
15.
J Org Chem ; 75(11): 3600-7, 2010 Jun 04.
Article in English | MEDLINE | ID: mdl-20443534

ABSTRACT

4,4-Difluoro-4-bora-3a,4a-diaza-s-indacene bridged bis(permethyl-beta-cyclodextrins) 1 was synthesized successfully through click chemistry, and it forms a well-defined linear assembly with 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin 2 via extremely strong host-guest interactions, which was identified by the methods of UV-vis, NMR, AFM, and TEM, respectively. Furthermore, the fluorescence resonance energy transfer from host spacer to porphyrin guest was investigated, showing that the energy transfer quantum yield is high to 94% in virtue of such a noncovalent path.

16.
Yao Xue Xue Bao ; 37(1): 41-5, 2002 Jan.
Article in Chinese | MEDLINE | ID: mdl-12579898

ABSTRACT

AIM: To develop a simple, fast and inexpensive approach as well as an instrument for detection of gene mutation. METHODS: Pyrosequencing based on bioluminometry assay was employed to detect gene mutation. Pyrosequencing is a method of sequencing by synthesis step-by-step using four enzymes, DNA-polymerase, ATP sulfurylase, luciferase and apyrase. The signal was produced by detecting pyrophosphate released during a dNTP incorporation. For mutation detection, a DNA fragment was amplified by PCR at first, followed by a single-stranded DNA preparation. In the second step, a short primer was annealed to the position just before the mutation point. Finally, specific dNTPs were added in terms of the template sequence. The mutation species can be readily determined by the sequence. RESULTS: A new instrument was developed for gene mutation detection by pyrosequencing. To iteratively inject small amount of each dNTP for the sequencing reaction, capillaries were used to connect dNTP reservoirs and the reaction chamber. Each dNTP was delivered by adding a gas pressure on the top of a corresponding dNTP reservoir, by which 0.2 microL of dNTP can be exactly added each time. It was theoretically proved that undesired liquid seep through the capillary did not affect the sequencing reactions in pyrosequencing. In addition, the three possible variants (wildtype, mutant and heterozygote) of a mutant point Cys275Ser in P53 gene exon 8 were determined by pyrosequencing using the instrument. A simple method was also described for rapidly distinguishing the type of a variant. CONCLUSION: The developed method is very simple, and the corresponding instrument is inexpensive and easy to operate, which can be used to detect many types of mutation.


Subject(s)
Genes, p53/genetics , Luminescent Measurements , Point Mutation , Exons/genetics , Humans
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