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Biomedical subjects

J Miao

Publications and source records attributed to J Miao.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Immune response in mice induced by C terminal encoding gene of Plasmodium falciparum histidine rich protein. 2].

OBJECTIVE: To explore the humoral and cellular immune responses in mice to eukaryotic expression recombinant plasmid encoding histidine rich protein 2 (HRP-II) of Plasmodium falciparum. METHODS: The start and stop codes were introduced into HRP-II gene fragment, the reading frame and the position of start and stop codes in HRP-II were identified by sequencing. HRP-II fragment containing the start and stop codes was cloned into pcDNA3.1 (-) to form pcDNA3.1 (-)/HRP-II. The BALB/c mice were immunized i.m. with the plasmids for 3 times in 3 weeks intervals. Two weeks after the last immunization, the sera and splenocytes were collected to investigate anti-HRP-II antibodies by ELISA and the splenocytes proliferation response to HRP-II. RESULTS: Sequence data show that the reading frame and the position of start and stop codes are correct. Restriction enzyme digestion indicated that the HRP-II gene fragment containing start and stop codes was successfully cloned into pcDNA3.1 (-). Mice raised significant anti-HRP-II antibodies after pcDNA3.1 (-)/HRP-II immunization, and the splenocytes proliferated prominently when stimulated with HRP-II protein. CONCLUSION: Eukaryotic expression recombinant plasmid encoding HRP-II gene can induce significantly humoral and cellular immune response in mice. HRP-II gene may be a good candidate for P. falciparum blood-stage multiple DNA vaccine.

Animals↗
PubMed1999

Simultaneous determination of oxalic, fumaric, maleic and succinic acids in tartaric and malic acids for pharmaceutical use by ion-suppression reversed-phase high performance liquid chromatography.

A reliable method for the simultaneous determination of oxalic, fumaric, maleic, and succinic acids in tartaric and malic acids for pharmaceutical use by reversed-phase ion-suppression high performance liquid chromatography is presented. HPLC was achieved on a Nova-Pak C18 column by isocratic elution using water adjusted to pH 2.10-2.15 with perchloric acid, and detection was by UV adsorption at a wavelength of 210 nm. This method was found to be superior to previous liquid chromatography as well as other classical assay, and to be an attractive choice for the analysis of these compounds.

Chromatography, High Pressure Liquid↗
PubMed1999

[Design and synthesis of anti-PML-RAR alpha antisense and its effects on the growth and apoptosis of NB4 cells].

OBJECTIVE: To synthesize antisense oligodeoxynucleotides (AS) targeting the fusion point region (FUAS) and the start codon region (STAS) of the long type PML-RAR alpha mRNA and investigate its stability, specificity and effects on the growth and apoptosis of NB4 cells. METHODS: NB4 cell apoptosis was assayed by flow cytometry, cell-fluorescence and DNA gel electrophoresis. Trypan blue exclusion was used for cell counts, and polyacrylamide gel electrophoresis for oligodeoxynucleotides. RESULTS: The synthesized 18 bp phosphorothioate oligodeoxynucleotides was stable, resistant to nuclease, and no unspecific effects. Both STAS and FUAS could inhibit the NB4 cell growth in a dose-dependent manner. Low concentration (20 micrograms/ml) of STAS or FUAS resulted in growth inhibition of 0%-11.3%, and the highest inhibition was found at concentration of 80 micrograms/ml (inhibition rate 50.0%-67.7%). Cell DNA content analyzed by flow cytometry showed the typical profile of apoptotic cells at 7th day, 9th day of treatment with FUAS. Percentages of apoptotic cells in FUAS-treated cells was 9.3%, 24.5%, 41.0% and 34.2% after 3, 5, 7 and 9 days of FUAS treatment, respectively. CONCLUSION: STAS and FUAS successfully synthesized and both of them could inhibit the growth and induce the cell apoptosis of NB4 cells.

Apoptosis↗
PubMed1999

[Effects of anti-PML-RAR alpha antisense on cell morphology and expression of PML-RAR alpha mRNA and protein of NB4 cells].

OBJECTIVE: To investigate the effects of anti-PML-RAR alpha antisense (FUAS) on cell morphology, expression of PML-RAR alpha mRNA and PML-RAR alpha/PML protein localization of NB4 cells. METHODS: PML-RAR alpha mRNA expression was assayed by RT-PCR and PML-RAR alpha/PML protein localization by immuno-fluorescence. RESULTS: NB4 cells were partially differentiated after 5 days of FUAS treatment and typical apoptosis was found after 7 days incubation with FUAS. The expression of PML-RAR alpha mRNA at 24 h was already down regulated in FUAS-treated cells. After 24 h, 72 h and 120 h incubation with FUAS, PML-RAR alpha mRNA showed 52.0%, 68.7% and 23.4% reductions, respectively, as compared with that of control. Immuno-fluorescence analysis with anti-PML monoclonal antibody showed disappearance of microgranules, residual granules becoming larger discrete dots at 24 h of FUAS treatment and almost disappearence of dots at 120 h. CONCLUSION: FUAS specifically blocks the expression and translation of PML-RAR alpha gene, makes the production of PML-RAR alpha fusion protein decrease or disappear and prompts cell differentiation.

Cell Division↗
PubMed1999

[Humoral immune response in mice to hybrid nucleic acid vaccines containing Plasmodium falciparum merozoite surface protein 1 block 17-based gene].

AIM: To analyse the humoral immune response in mice to nucleic acid vaccines (VR1012/HG-MSP1-17 for intracellular expression or VR1012/TPA/HG-MSP-17 for secretion) containing Plasmodium falciparum merozoite surface protein 1 (MSP1) 17 block gene and gene fragment of several T cell epitopes from MSA1, MSA2, RESA, IL-1 and TT. METHODS: BALB/c or C57BL/6 mice received three times intramuscular immunization with 200 micrograms/100 microliters or 100 micrograms/100 microliters of VR1012/HG-MSP1-17 or VR1012/TPA/HG-MSP1-17 per mouse each time. Anti-HG or anti-MSP1-17 antibodies were monitored by indirect ELISA. RESULTS: BALB/c and C57BL/6 mice immunized with 100 micrograms/100 microliters of VR1012/HG-MSP1-17 per mouse raised significantly anti-HG and anti-MSP1-17 antibodies, but the levels of antibodies were not high. BALB/c mice immunized with 200 micrograms/100 microliters of VR1012/HG-MSP1-17 per mouse raised higher anti-HG antibodies but not anti-MSP1-17 antibodies. BALB/c mice immunized with 200 micrograms/100 microliters of VR1012/TPA/HG-MSP1-17 per mouse raised low level of anti-HG antibodies only. CONCLUSION: VR1012/HG-MSP1-17 is more immunogenic than VR1012/TPA/HG-MSP1-17.

Animals↗
PubMed1998

Close vicinity of Lhc b1 and Lhc b4 in Photosystem II--membrane fragments as verified by chemical cross-linking.

The nearest neighbourhood of pigment-protein complexes within Photosystem II (PSII) membrane fragments has been studied by means of chemical cross-linking with o-phthalaldehyde (OPA) in conjunction with protein-chemical techniques. By means of OPA-induced cross-linking a major conjugate of about 60 kDa has been identified. This conjugate was shown to consist of two pigment-protein complexes of light-harvesting complex II (LHC II), Lhc b1 (CP27) and Lhc b4 (CP29) by means of SDS/PAGE in combination with an immunological analysis using mAbs directed against Lhc b4 and by matrix-assisted-laser-desorption-ionization mass spectrometry (MALDI-MS) and sequence analysis of peptides derived from a proteolytic digest of the conjugate. Domains of Lhc bl and Lhc b4 have been localized to a distance of not more than 5 A within LHC II. Our results are discussed in the light of recent models on the topography of the two subunits within the antenna system of Photosystem II.

Amino Acid Sequence↗
PubMed1998

Interactions of mild hyperthermia, cisplatin and split dose irradiation in human ovarian carcinoma cells.

PURPOSE: Human ovarian cancer cells were evaluated to determine whether combination treatment with mild hyperthermia and cisplatin could inhibit repair of sublethal radiation damage. MATERIALS AND METHODS: Human ovarian carcinoma cell lines A2780S (parental line) and A2780CP (cisplatin resistant variant) were used in this study. Cisplatin at concentrations of 1 or 3 microg/ml was given concomitantly with 1 h of heating at 40 degrees C either immediately before or after irradiation. Survival was determined using a colony-forming assay. RESULTS: Neither mild hyperthermia nor cisplatin treatments alone affected sublethal damage repair. The combined treatment showed an effect in both cell lines and was treatment sequence-dependent. The effect was greater in the parental cell line. CONCLUSIONS: The data show that combined treatment of cisplatin and hyperthermia may have clinical efficacy at cisplatin concentrations and hyperthermia temperatures which by themselves have little to no effect.

Animals↗
PubMed1998

[Rapid construction of recombinant baculovirus carrying hepatitis B virus surface antigen gene by using a novel baculovirus shuttle vector(Bacmid)].

In order to express the HBV surface antigen (HBV) efficiently by using the Bac-to-Bac system and to produce HBsAg for diagnosis and vaccine development of HBV, a recombinant donor plasmid pFB-BS carrying HBsAg gene was constructed. The gene was inserted into shuttle plasmid (Bacmid) in E. coli DH10Bac with the help of Tn7 transposition system. The recombinant Bacmid was examined by PCR and transfected to Sf9 cells. HBsAg was expressed under the control of polyhedrin promoter of baculovirus in insect cells and was identified by ELISA. The quantity of the expression reached to 2 micrograms/10(6) cells and most production was within cells. Our data suggested that the Bac-to-Bac system can be used successfully and rapidly in the expression of viral gene.

Baculoviridae↗
PubMed1997

2/3 osteotomy for lengthening the mandible in dogs by gradual distraction.

Successful lengthening of the mandible by gradual distraction has been reported previously. There are various methods for osteotomy before distraction osteogenesis. In this paper, a new type of osteotomy, performed on growing dogs as a model, is reported. Ten mongrel dogs, aged 6 months, were studied. A unilateral 2/3 osteotomy was performed, and an external lengthening device was fixed to the mandible perpendicular to the osteotomy. Seven days after the operation, the mandible was lengthened by 1 mm per day. The dogs were sacrificed for histological study at the end of the distraction on days 14, 28, 56 and 120 following completion of the distraction.

Animals↗
PubMed1997

Unstable minisatellite expansion causing recessively inherited myoclonus epilepsy, EPM1.

Progressive myoclonus epilepsy of Unverricht-Lundborg type (EPM1; MIM 254800) is an autosomal recessive disorder that occurs with a low frequency in many populations but is more common in Finland and the Mediterranean region. It is characterized by stimulus-sensitive myoclonus and tonic-clonic seizures with onset at age 6-15 years, typical electroencephalographic abnormalities and a variable rate of progression between and within families. Following the initial mapping of the EPM1 gene to chromosome 21 (ref. 6) and the refinement of the critical region to a small interval, positional cloning identified the gene encoding cystatin B (CST6), a cysteine protease inhibitor, as the gene underlying EPM1 (ref. 10). Levels of messenger RNA encoded by CST6 were dramatically decreased in patients. A 3' splice site and a stop codon mutation were identified in three families, leaving most mutations uncharacterized. In this study, we report a novel type of disease-causing mutation, an unstable 15- to 18-mer minisatellite repeat expansion in the putative promoter region of the CST6 gene. The mutation accounts for the majority of EPM1 patients worldwide. Haplotype data are compatible with a single ancestral founder mutation. The length of the repeat array differs between chromosomes and families, but changes in repeat number seem to be comparatively rare events.

Cystatin B↗
PubMed1997

[Core protein of hepatitis C virus expressed in transgenic mice is associated with the expression of Fas molecule].

Hepatitis C virus (HCV) is a leading cause of morbidity and mortality worldwide but the pathogenesis of liver cell injury and the molecular mechanism of persistent infection of HCV are not well understood. The aim of this work is to establish the animal model of HCV infection for studying the biosynthesis and pathogenesis of HCV structural protein in transgenic mice. The structural genes (C+ E1 + E2) and 5'-uncoding region gene (5'UCR) of HCV isolated from China was inserted into pcDNA3 vector. The transgenic mice were produced by microinfecting this plasmid into mouse (C57BL/6 x ICR) embryos and the integrated mice were identified. The expression of core protein of HCV and mFas molecule were confirmed by immunohistochemical analysis using monoclonal antibody. The results revealed that the expression of core protein was detected in many mouses' tissues with nuclear staining, while the heart tissue was with cytoplasmic staining. The expression level in tissues was indicated as: heart>lung>kidney>liver. At meantime, Fas molecule was detected in heart, kidney and liver tissues, and the expression of Fas was parallel to that of core protein. Transgenic mouse containing HCV structural gene was established and the expression of Fas molecule may be associated with the expression of core protein of HCV. The Fas system or other signaling pathway to the programmed cell death may play important roles in HCV infection. Our transgenic mouse will provide a useful animal model to critically address issues of immune pathogenesis, direct cytopathic potential and carcinogenesis of the structural protein of HCV.

Animals↗
PubMed1996

Mutations in the gene encoding cystatin B in progressive myoclonus epilepsy (EPM1)

Progressive myoclonus epilepsy of the Unverricht-Lundborg type (EPM1) is an autosomal recessive inherited form of epilepsy, previously linked to human chromosome 21q22.3. The gene encoding cystatin B was shown to be localized to this region, and levels of messenger RNA encoded by this gene were found to be decreased in cells from affected individuals. Two mutations, a 3' splice site mutation and a stop codon mutation, were identified in the gene encoding cystatin B in EPM1 patients but were not present in unaffected individuals. These results provide evidence that mutations in the gene encoding cystatin B are responsible for the primary defect in patients with EPM1.

Amino Acid Sequence↗
PubMed1996

A computer-based statistical pattern recognition for Doppler spectral waveforms of intracranial blood flow.

A computer-based statistical pattern recognition system has been developed for the analysis of transcranial Doppler (TCD) spectral waveforms of the intracranial middle cerebral artery with varying degrees of increased intracranial pressure. This system extracts multidimensional features from TCD waveforms and performs a cluster analysis of those features. The system can automatically recognize the pattern of spectral waveform and classify it as a normal, abnormal, or borderline subclass of TCD spectral waveform. An optimum decision function was generated based on the Bayes Gaussian classifier. The accuracy of the Bayes Gaussian model the spectral waveforms reaches 100% by estimating posterior probability and using the resubstituting method of estimating misclassification in the training TCD data.

Artificial Intelligence↗