Biomedical subjects

Xiao-rong Liu

Publications and source records attributed to Xiao-rong Liu.

12 recordsLinked to original sources

PubMed2006

[Expression and purification of human MT-2a fusion protein in prokaryotic cells and preparation of its antiserum].

AIM: To express and purify human MT-2a in prokaryotic cells and to prepare the MT-2a-specific rabbit antiserum. METHODS: GST-MT-2a fusion protein was expressed after IPTG induction and further purified with Glutathione Sepharose 4B. Then the purified GST-MT-2a fusion protein was used to immunize New Zealand rabbits. The titer and specificity of rabbit antiserum were evaluated by double immunodiffusion, ELISA and Western blot. RESULTS: GST-MT-2a fusion protein was highly expressed. The final yield of the pure GST-MT-2a was about 38 mg per liter of bacterial culture. Its antiserum with high specificity and potency was also obtained. CONCLUSION: The successful expression of GST-MT-2a fusion protein in E. coli and the preparation of MT-2a specific rabbit antiserum will be valuable for the study on the function of human MT-2a.

Antibody Specificity↗

PubMed2005

Analysis of germline mutations in the APC gene in familial adenomatous polyposis patients.

OBJECTIVE: This study was aimed at establishing an efficient mutation analysis technique system to screen the germline mutations in the adenomatous polyposis coli (APC) gene that predisposes the disease susceptibility in familial adenomatous polyposis (FAP) and to investigate the relationship between genotype and phenotype of APC gene. METHODS: Genomic DNA was extracted from the peripheral blood lymphocytes of 22 patients with clinically diagnosed FAP and was forwarded to screening for germline mutations by using denaturing high-performance liquid chromatography(DHPLC), protein truncation test (PTT) and DNA sequencing in APC gene. Analysis of genotype-phenotype was also performed on the clinical data of the FAP patients. RESULTS: Thirteen APC germline mutations were identified in 22 FAP patients. All of the mutations were nonsense or framshift mutations. Analysis of genotype-phenotype demonstrated that the FAP patients with mutations in the 5'or 3'extreme parts of the APC gene showed mild clinical symptoms. However, the FAP patients with mutations in the middle of the APC gene displayed typical or severe clinical symptoms. CONCLUSION: The technique system established in this study can efficiently and sensitively detect the mutations in APC gene. It is useful in the molecular diagnosis of pre-symptomatic FAP cases in FAP family. The clinical features of FAP patients may be related to their genotypes of APC gene.

Adenomatous Polyposis Coli↗

PubMed2005

[Correlation between B-natriuretic peptide and hemodynamics in patients with decompensated heart failure and clinical significance].

OBJECTIVE: To determine the correlation between the serum level of B-natriuretic peptide (BNP) and hemodynamic variables and to evaluate the diagnostic value of BNP in patients with decompensated heart failure (HF). METHODS: BNP levels (TRIAGE BIOSITE Diagnostics, San Diego, USA) were obtained by a rapid immunofluorescence assay in 117 patients with dyspnea including cardiogenic group (75 patients) and lung disease (42 patients). Hemodynamic parameters of 53 patients [male 28, female 25, mean age (71.6 +/- 9.8) years] with HF were determined and left ventricular end-diastolic diameter (LVEDD) of all patients were measured by echocardiogram. RESULTS: Pulmonary capillary wedge pressure (PCWP, mm Hg), mean pulmonary arterial pressure (MPAP, mm Hg), right atrial pressure (RAP, mm Hg) and BNP (ng/L) levels according to New York Heart Association (NYHA) class were: 16.10 +/- 3.50, 22.50 +/- 4.68, 3.11 +/- 1.90, 271.25 +/- 159.29 in NYHA class II, respectively; 21.50 +/- 4.42, 28.60 +/- 9.35, 8.95 +/- 3.86, 619.58 +/- 237.48 in NYHA class III; 29.28 +/- 8.61, 36.50 +/- 12.32, 15.27 +/- 4.96, 1519.28 +/- 618.62 in NYHA class IV (P < 0.01-0.05), respectively. PCWP, MPAP, RAP and plasma BNP levels were directly proportional to cardiac function. The plasma BNP levels had also significant positive correlations with PCWP, MPAP, RAP, (r = 0.59, 0.50, 0.32, P < 0.05-0.01). BNP level [(918.48 +/- 453.25) ng/L] of the group with LVEDD (n = 24) > or = 60 mm was much higher than that of the group with LVEDD (n = 29) < 60 mm [(298.58 +/- 167.51) ng/L]. However, the latter was significantly higher than that in pulmonary dyspnea group with a normal left and right ventricular end-diastolic diameter [(35.4 +/- 26.4) ng/L, P < 0.01]. There was a great difference of BNP between cardiogenic dyspnea group [(761.30 +/- 480.47) ng/L]and lung dyspnea group [(35.4 +/- 26.4) ng/L], P < 0.01. CONCLUSIONS: The plasma BNP levels had significant positive correlations with PCWP, MPAP, RAP. BNP is a cardiac neurohormone secreted from cardiac ventricles as a response to ventricular volume expansion and pressure overload. Rapid testing BNP should be of help to differentiate pulmonary dyspnea from cardiac etiologies.

Aged↗

PubMed2005

The analysis for identifying large DNA fragment aberrations of MSH2 and MLH1 genes from familial colorectal cancer in China.

OBJECTIVE: To investigate the frequency of large fragment aberrations of MSH2 and MLH1 genes from Chinese colorectal cancer (CRC) patients with family history. METHODS: Sixteen exons of MSH2, nineteen exons of MLH1 and seven DNA sequences from the other genes of the samples were screened and checked by multiplex ligation dependent probe amplification (MLPA). First, the methodology was confirmed by testing the positive and negative control samples. Then, 32 CRC or hereditary nonpolyposis colorectal cancer (HNPCC) patients with family history and 20 cases of sporadic CRC were applied to investigate for the large fragment aberrations of MSH2 and MLH1 genes. RESULTS: The genomic DNA fragment deletions of all positive controls were identified and verified by MLPA. Three cases of 32 familial (hereditary) CRC/HNPCC were detected and identified to be the germline heterozygous deletions of MSH2 gene, of which exons 1-7 were deleted from patient No.3, exon 11 from No.25 and exons 2-6 from No.11. However, no genomic DNA fragment aberration of either MSH2 or MLH1 gene was uncovered from 20 sporadic CRC. CONCLUSION: Large DNA fragment aberrations of MSH2 gene was a frequent cause of Chinese HNPCC and CRC patients with family history, and the identification of those aberrations should be included in the regular genetic analysis for CRC/HNPCC patients.

Adaptor Proteins, Signal Transducing↗

PubMed2004

[The detection of microsatellite instability by ion-pair reversed-phase high performance liquid chromatography].

OBJECTIVE: To set up a sensitive and stable technique which has high throughout to detect the instability of microsatellite DNA. METHODS: Genomic DNA extracted from the cancer tissues and their normal tissues were subjected to microsatellite instability(MSI) analysis on five of DNA markers in 115 sporadic colorectal cancers by means of PCR and ion-pair reversed-phase high performance liquid chromatography. Genomic DNA extracted from lymphocytes in blood of 20 normal persons were analysed and used as the standard control. RESULTS: Seventeen (14.8%) MSI-H and 23(20.0%) MSI-L were found in 115 sporadic colorectal cancers. The rates of MSI in the young patients and old patients were much higher than that in the middle-age patients (P<0.05). And the rate of MSI in low differentiation group was also much higher than that in high or middle differentiation groups (P<0.05). CONCLUSION: The method the authors developed is a sensitive and accurate technique to detect MSI and has a high throughput.

Adult↗

PubMed2004

[Morphological studies on embryonic gonad development in Kunming mice].

OBJECTIVE: To observe the morphological changes of embryonic gonad in Kunming mice in different developmental stages. METHODS: HE stained paraffin sections of the embryonic mouse gonads in different developmental stages were prepared for evaluation of the morphological changes. RESULTS: The genital ridge was identified on the 11th day after the mating and undifferentiated gonad detected on the 12th day, while 1 d later, sexual identification was possible by examining the sections. The male gonad developed into testis by forming seminiferous tubules and Sertoli cells on the 14th day. On the 16th day, the female gonad evolved into the ovary with obvious differentiation of the cortex and medulla and till the 20th day, more seminiferous tubules occurred in the testis with cavities containing numerous spermatogenic cells at different developing phases; also observed was a mass of rough sex cords that produced ovarian follicles surrounding the ovary and contained large quantity of primitive oogonia. CONCLUSIONS: Days 11-12 after mating might be the best time for separating primordial germ cells from undifferentiated mouse gonad.

Animals↗

PubMed2004

[Ultrastructural changes in muscular tissues of dystrophin/utrophin double-knockout mice after bone marrow-derived mesenchymal stem cell transplantation].

OBJECTIVE: To observe the ultrastructural changes in the muscular tissues of Duchenne muscular dystrophy mouse models with dystrophin/utrophin double-knockout (DKO) after transplantation of bone marrow-derived mesenchymal stem cells (MSCs). METHODS: The fifth passage of in vitro cultured MSCs from SD rats were transplanted into the DKO mice via the tail vein, and the ultrastructural changes in the gastrocnemius of the recipient rats were observed using transmission electron microscope 15 weeks after the transplantation. RESULTS: The fifth passage of the in vitro cultured MSCs growing in colonies possessed good homogeneity with low immunogenic activity for transplantation via the tail vein. After transplantation, the DKO mice exhibited improved motor function and prolonged survival period. Ultrastructural observation of the gastrocnemius of the recipient DKO mice revealed much alleviated sarcolemmal disruption, dissociation and edema of the subsarcolemmal tissues, central nuclear shift, loosening of the local myofibrils, inflammatory cell infiltration and connective tissue hyperplasia in comparison with the tissues from the DKO mice without MSC transplantation. Fusion of several immature nuclei was observed in the subsarcolemmal region. CONCLUSIONS: MSCs possess strong plasticity in vitro and in vivo, and after transplantation, the MSCs may migrate to lesioned muscular tissues via the blood circulation to participate in the repair and regeneration the atrophied muscular tissues.

Animals↗

PubMed2004

[Application of the Bgl II-Bln I dosage test to gene diagnosis of facioscapulohumeral muscular dystrophy 1A gene].

OBJECTIVE: To increase the sensitivity and specificity of conventional gene diagnosis of facioscapulohumeral muscular dystrophy 1A(FSHD1A) by analyzing the distribution of translocation between chromosomes 4q35 and 10q26 in suspected FSHD cases. METHODS: The Bgl II- Bln I dosage test was performed to detect translocation between chromosomes 4q35 and 10q26 in 7 cases of presymptomatic FSHD patients showing positive result in gene diagnosis and 5 cases of sporadic FSHD patients showing negative result in gene diagnosis. DNA samples were digested with Bgl II and Bln I, followed by agrose gel electrophoresis. Probe p13E-11 was labeled with alpha-(32) P dCTP, followed by Southern hybridization. Then the ratio between the chromosomes 4 and 10 derived signal intensities was judged and hence was made known whether there was interchromosomal translocation between chromosomes 4 and 10. RESULTS: The Bgl II-Bln I dosage test revealed a translocation from chromosome 4q35 to 10q26 in one presymptomatic FSHD patient, thus indicating the result of gene diagnosis for her might be false positive. There was one translocation from chromosome 10q26 to 4q35 detected in one sporadic FSHD patient, indicating the result of gene diagnosis for her might be false negative. There were no translocations between chromosomes 4 and 10 in the other 10 cases. CONCLUSION: The Bgl II-Bln I dosage test can detect the translocation between chromosomes 4q35 and 10q26. It can improve the accuracy of the conventional method for gene diagnosis of FSHD1A.

Adolescent↗

PubMed2004

[Dystrophin and utrophin expression in muscle tissues of DMD mouse model after transplantation treatment by bone marrow mesenchymal stem cells].

OBJECTIVE: To observe dystrophin and utrophin expression in muscle tissues of Duchenne muscular dystrophy (DMD) mouse model (dko mouse) after having been treated with bone marrow mesenchymal stem cells (MSC) transplantation. METHODS: The fifth generation of MSCs, cultured in vitro, was transplanted into dko mice by tail vein. The fluorescent expression of dystrophin and utrophin in gastrocnemius muscle tissue of dko mouse was detected and the average optical density of positive fibers was calculated. RESULTS: MSCs that had been cultured for three generations had good homogeneousness and the immunological reaction after vein transplantation was low. There was an increasing tendency of dystrophin and utrophin fluorescent expression in sarcolemma of dko mouse within 5-20 weeks. Significant difference existed in fluorescent average optical density of positive fibers fifteen weeks before and after cell transplantation. CONCLUSIONS: MSC has strong plasticity both in vitro and in vivo. MSC has a trend to reach the injured muscle tissues and turn into muscle fibers, which express dystrophin and utrophin. There is some plerosis function for myatrophy of dko mouse by MSC transplantation.

Animals↗

PubMed2003

[Bone marrow stem cells transplantation improve locomotive function of dystrophin/utrophin gene double knock-out mice].

OBJECTIVE: Study the improvement of locomotive faculty of dystrophin/utropin gene double knock-out mice (dko mice) by transplanting bone marrow stem cells. METHODS: The bone marrow stem cells of C57BL/6 mice (4- to 5-weeks age) were cultured in vitro for three days, before transplanted intravenously (1.0 x 10(7) for each) into 11 dko mice (7- to 8-weeks age). The dko mice were irridiated with 7Gy gamma-ray before transplantation. 8-9 weeks after transplantation, the locomotroy function, electromyography items and expression of dystrophin in transplanted mice and controls were observed. RESULTS: 8-9 weeks after transplantation, the dropping times of hauling wire were 3.09 +/- 2.47, compared with that of the control dko mice(16.78 +/- 3.60), there are distinct differences. About electromyography items, the duration of active potential and amplitude of maxim contractions were (4.99 +/- 1.62) ms and(2872 +/- 1474.33) microV, compare with those of control dko mice(3.69 +/- 0.40) ms and(1210.0 +/- 551.0) microV, respectively, about 7% fibers of the muscle tissue of transplanted dko mice expressed dystrophin protein. CONCLUSIONS: 8-9 weeks after transplanted with homology bone marrow stem cells, the locomotive function and electromyography items of transplanted dko mice were obviously improved, and about 7% muscle tissue fibers of the mice expressing dystrophin protein were observed. It suggested that there is an ideal prospect for DMD therapy with bone marrow stem cells transplantation.

Animals↗

PubMed2003

[Translocation between chromosomes 4q35 and 10q26 in facioscapulohumeral muscular dystrophy].

OBJECTIVE: To investigate the distribution of translocation between chromosomes 4q35 and 10q26 in facioscapulohumeral muscular dystrophy (FSHD) patients and normal individuals. METHODS: The Bgl II-Bln I dosage test was performed to study the distribution of translocation between chromosomes 4q35 and 10q26 in 70 cases of FSHD patients, 55 cases of kindred with FSHD, and 52 cases of normal controls. RESULTS: (1) In normal individuals, the frequency of translocation between chromosomes 4q35 and 10q26 is 19.23%. The frequency of translocation from chromosome 4q35 to 10q26 and that from chromosome 10q26 to 4q35 are both 9.62%. (2) In the FSHD patients, the frequency of translocation between chromosomes 4q35 and 10q26 is 18.57%. The frequency of translocation from chromosome 4q35 to 10q26 and that from chromosome 10q26 to 4q35 are 12.86% and 5.71% respectively. CONCLUSIONS: The translocation between chromosomes 4q35 and 10q26 was frequently observed in both normal Chinese population and FSHD patients. No significant difference was observed between them.

Adolescent↗

PubMed2003

[Large deletion in mismatch repair genes uncovered by quantitative multiplex PCR-high performance liquid chromatography system].

OBJECTIVE: Establishing a new method on the basis of multiplex PCR-high performance liquid chromatography (HPLC) for screening a large deletion in mismatch repair genes. METHODS: Thirty-five pairs of primers were used to amplify all 16 exons of MSH2 and all 19 exons of MLH1 gene in 8 multiplex PCR. The products of multiplex PCR were analysed for the large deletion with Double Strand DNA Analysis System of HPLC. Firstly, validation of the method was tested on positive and negative controls in blind analysis. Secondly, 14 blood cell DNA samples from hereditary nonpolyposis colorectal cancer (HNPCC) patients and 13 colorectal cancer (CRC) tissues DNA samples from sporadic CRC patients were checked with the new developed method. RESULTS: (1) the genomic deletions in all 4 of positive controls were identically uncovered with the new method; (2) a novel germline and a novel somatic large deletions were unveiled in 1/14 HNPCC patients and in 1/13 CRC tissues. CONCLUSION: The method developed on multiplex PCR-HPLC is reliable for uncovering large genomic deletion in mismatch repair genes, and can be taken as a valuable addition to mutation screening system.

Adaptor Proteins, Signal Transducing↗