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Biomedical subjects

Yan Wang

Publications and source records attributed to Yan Wang.

At least 289 records · Page 16Linked to original sources

[Nano flow multidimensional liquid chromatography for proteome analysis of rat liver].

A nano flow comprehensive multidimensional liquid chromatography was developed. By using this separation platform, complex samples can be injected, desalted, separated and analyzed in complete automatization. Coupling of the strong cation-exchange (SCX) with capillary reversed-phase liquid chromatography (cRPLC) is described for proteomics of rat liver. A step gradient was applied for SCX column, and a linear gradient was applied for RPLC. The flow rate through the nano scale analytical column during the separation process was maintained at 200 nL/min. The peak capacity for the nano-2D-LC was up to 620 under these conditions.

Animals↗

[A serious complication-obstructive sleep apnea hypopnea syndrome after velopharyngeal ring ligation procedure: report of 6 cases].

PURPOSE: To discuss the occurrence and characteristics of obstructive sleep apnea hypopnea syndrome (OSAHS) after velopharyngeal ring ligation procedure (VRLP). METHODS: Seven hundred and eight cleft palate patients underwent velopharyngeal ring ligation procedure from 1997 to 2003. Nine cases were found having some suspicious symptoms of OSAHS after operation and 6 of them were confirmed as OSAHS by polysomnography. Six VRLP patients without OSAHS as controls were examined with polysomnography. Chi-square test and t test were used to determine the statistical differences between the groups. RESULTS: Six cases of 708 patients met the criterion of severe OSAHS and the incidence of OSAHS after VRLP in children below 12 years was 1.8%. Compared with controls, more arousals and longer awakening were found in OSAHS group, the ratio of III and IV phase of NREM and REM in total sleep was significantly decreased (P<0.01). CONCLUSION: OSAHS was likely to occur in VRLP patients below 12 years. Many feature of this kind of OSAHS were different from the ordinary pediatric OSAHS. It showed that OSAHS after VRLP was characterized by more apneas, less partial upper airway obstruction and associated with distinguished staged desaturation.

Child↗

TCM treatment for 63 cases of senile dyssomnia.

In order to study the therapeutic effects of the TCM drugs on senile dyssomnia, 121 such patients were randomly divided into a treatment group of 63 cases (given the TCM drugs) and a control group of 58 cases (given estazolam). The changes shown in the SDRS and HAMA scores and the other indexes were observed in both of the two groups to evaluate the therapeutic effects. The results showed that the effective rate was 76.3% in the treatment group, and it was 69.1% in the control group; and that the TCM drugs had better effects in improving such symptoms as lethargy, dry mouth, and rebound of insomnia. Therefore, it can be concluded that the effect of the TCM drugs isbetter for senile dyssomnia than that of the Western drug estazolam.

Aged↗

Protective action of acupuncture and moxibustion on gastric mucosa in model rats with chronic atrophic gastritis.

OBJECTIVE: To probe the mechanism of acupuncture and moxibustion in atrophic gastritis so as to provide a basis for clinical treatment. METHOD: Observe the effects of acupuncture and moxibustion at the points of Zusanli, Zhongwan and Tianshu on gastric mucosa in model rats with chronic atrophic gastritis. RESULTS: Acupuncture and moxibustion can increase the contents of PGE2alpha, PGF2alpha and cAMP, and decrease the content of cGMP in the tissue of gastric mucosa. CONCLUSION: Acupuncture and moxibustion shows cytoprotection on gastric mucosa, so it is an effective method for treating chronic atrophic gastritis.

Acupuncture↗

[Expression of MAGE-A1 in human hepatoma cell lines associated with genic hypomethylation].

OBJECTIVES: To investigate the correlation between MAGE-A1 mRNA expression and genic demethylation in hepatoma cell lines. METHODS: Total RNA and genomic DNA were prepared from 10 human hepatoma cell lines. MAGE-1 mRNA expression was determined with RT-PCR and the level of genome-wide demethylation was evaluated by enzyme digestion and Southern blot assay. The genomic DNA was digested by HpaII, then the promoter of MAGE-A1 gene was amplified with primers CDS21, EDP4 and CDS20. EDP4 and the PCR products were further hybridized with a probe to detect the methylation in the promoter of the MAGE-A1 gene. HLA-A locus was typed using SSP kit. RESULTS: In cell lines QGY-7703, SMMC-7721, HLE, BEL-7402, BEL-7404 and BEL-7405, MAGE-A1 mRNA expression was positive and cell differentiation was moderate or low. In cell lines of HepG2 2.2.15, HepG2, QGY-7701 and Huh7, MAGE-A1 mRNA expression was negative and cell differentiation was well or moderate. The level of genomic demethylation in MAGE-A1 mRNA positive cell lines was much higher than that in MAGE-A1 mRNA negative cell lines (t = 2.896, P = 0.02). The methylation analysis showed that methylation in the promoters of MAGE-A1 gene of HepG2 2.2.15, HepG2, QGY-7701 and Huh7 was high, and that methylation in those of SMMC-7721, HLE, BEL-7402, BEL-7404, and BEL-7405 was low. CONCLUSION: The results suggest that MAGE-A1 mRNA expression in the human hepatoma cell lines is associated with genic hypomethylation.

Antigens, Neoplasm↗

[Impaired endothelium-dependent vasodilation and arterial elasticity in patients with coronary artery disease].

OBJECTIVE: To investigate the change in endothelium-dependent vasodilation and arterial elasticity and the association between them in patients with coronary artery disease (CAD). METHODS: Thirty patients with CAD and thirty control subjects were recruited for this study. Flow-mediated dilation (FMD) in the brachial artery was evaluated by ultrasound Doppler flow method. They also underwent a non-invasive assessment of C(1) large artery and C(2) small artery indices by using pulse wave analysis. RESULTS: FMD was significantly reduced in CAD group compared with that in control group [(5.17 +/- 2.13)% vs (11.1 +/- 4.36)%, P < 0.05], C(1) large artery elasticity index was similar between the two groups [(11.59 +/- 4.56) ml/mm Hg x 10 vs (12.11 +/- 3.82) ml/mm Hg x 10, P > 0.05]. However, C(2) small artery elasticity index was significantly reduced in CAD group compared with that in control group [(4.20 +/- 1.80) ml/mm Hg x 100 vs (6.26 +/- 2.36) ml/mm Hg x 100, P < 0.05]. There was a positive association between reduced C(2) small artery elasticity index and impaired FMD (r = 0.53, P < 0.05). CONCLUSIONS: There were impaired endothelium-dependent vasodilation and reduced C(2) small artery elasticity index in the patients with CAD, which were closely correlated with each other. The present study suggested that the measurement of C(2) small artery elasticity might be used as a novel index for the determination of endothelial function.

Aged↗

[A study of association between age-related circulating endothelial progenitor cells and arterial elasticity].

OBJECTIVE: Reduced arterial elasticity is a hallmark of aging in healthy humans independently of diseases and endothelial-cell injury and dysfunction may be responsible for this fall in arterial elasticity. We hypothesized that circulating endothelial progenitor cells (EPCs) are involved in endothelial repair and that lack of EPCs contributes to impaired arterial elasticity. METHODS: A total of 56 healthy male volunteers were divided into young (n = 26) and elderly (n = 30) groups. Large and small artery elasticity indices were non-invasively assessed by using pulse wave analysis. Flow cytometer was used to count the number of circulating CD34(+) mononuclear cells (MNCs), which were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. EPCs were characterized as adherent cells double positive staining for DiI-acLDL uptake and lectin binding with using fluorescent microscope. RESULTS: C(1) (large artery elasticity index) and C(2) (small artery elasticity index) were significantly reduced in the elderly group compared with those in the young group (11.73 +/- 1.45 vs 16.89 +/- 1.69 ml/mm Hg x 10, P < 0.001; 8.40 +/- 1.45 vs 10.58 +/- 1.18 ml/mm Hg x 100, P < 0.001 respectively). In parallel, the number of circulating EPCs was significantly reduced in the elderly group compared with the young group (0.13 +/- 0.02 vs 0.17 +/- 0.04%, P < 0.05). The number of circulating EPCs correlated with C(1) large and C(2) small artery elasticity indices (r = 0.47, P < 0.01; r = 0.4, P < 0.01). Fluorescent microscope was used to identify EPCs, which were double positive staining for DiI-acLDL uptake and lectin binding. CONCLUSION: The present findings suggested that the fall in circulating EPCs with subsequently impaired endothelial-cell repair and function might contribute to reduced arterial elasticity in humans with aging. The decrease in circulating EPCs could serve as a surrogate biologic measure of vascular function and human age.

Adult↗

[Rapid detection of rifampin resistance of Mycobacterium tuberculosis using high-throughput pyrosequencing technique].

OBJECTIVE: To develop a pyrosequencing approach to rapid detection of rifampin resistance in Mycobacterium tuberculosis based on characterization of all possible mutations in the 81 bp core region. METHODS: Two pyrosequencing sequencing primers and 1 pair of PCR primers were chosen for pyrosequencing analysis. The sensitivity of the pyrosequencing approach was determined by assaying PCR products generated from 10-fold serial dilutions of the DNA from Mycobacterium tuberculosis H(37) Rv strains. The efficacy of the pyrosequencing approach was evaluated by analyzing clinical Mycobacterium tuberculosis isolates with known antibiotic phenotypes. RESULTS: Rifampin resistance could be determined within 2 hours after PCR amplification and single-stranded template preparation by using only two pyrosequencing reactions. About 50 fg DNA/reaction was required in order to get sufficient PCR product for producing a long, clear and accurate pyrosequencing pattern. A total of 41 Mycobacterium tuberculosis isolates were tested and the results were concordant with those based on drug susceptibility testing and conventional DNA sequencing. CONCLUSION: The pyrosequencing technique is simple to perform and can be used as a rapid, high-throughput and efficient method for detecting rifampin resistance in Mycobacterium tuberculosis.

Antitubercular Agents↗

[Clinical features and the mutation of Leber's hereditary optic neuropathy in Chinese patients].

OBJECTIVE: To analyze the mutation of Leber's hereditary optic neuropathy (LHON) and the clinical features in Chinese patients. METHODS: The primary mtDNA mutations (3460A, 11778A and 14484C) of 156 patients (110 probands and 46 maternal relatives with LHON) were detected by mutation-specific priming polymerase chain reaction, heteroduplex-single strand conformation polymorphism polymerase chain reaction, restriction fragment length polymorphisms and measurement of DNA sequence. The clinical features were analyzed by retrospective study. RESULTS: The 11778A mutation was found in 100 probands (90.9%), the 3460A mutation was found in 2 (1.8%), and the 14484C was found in 8 (7.3%) of the 110 probands. The visual acuity at onset of the disease was 0.01 or worse in 44 (17.6%) of 250 eyes with the 11778A mutation, but in none of 79 eyes with the 14484C mutation. The visual acuity was 0.1 or better in 76 (29.6%) of 250 eyes with the 11778A mutation, but in 49 (87.3%) of 56 eyes with the 14484C mutation. And 6.8% of 250 eyes with the 11778A mutation recovered a mean final visual acuity of 0.03, whereas 50% of 56 eyes with the 14484C mutation recovered a mean final visual acuity of 0.8. CONCLUSION: In Chinese LHON patients the 11778A, 14484C primary mutations are common. The clinical features are associated with the site of primary mutation. The visual acuity at onset of the disease and the visual recovery of the eyes with 14484C mutation were better than the eyes with the 11778A mutation.

Adolescent↗

[Influence of dexamethasone on fusion of embryonic palatal medial edge epithelium in mouse palatal shelves in vitro].

OBJECTIVE: To study the effect of dexamethasone on the differentiation and proliferation of type A mouse palatal medial edge epithelial cells when there is type A mouse embryonic palatal mesenchymal cells. METHODS: The mouse palatal shelves were harvested from a female mouse of gestation day 14 by microsurgical dissection and cultured in vitro. The differentiation was investigated through microscope and transmission electron microscope under condition of the palatal shelves fusion. RESULTS: Dexamethasone promoted the palatal medial edge epithelium differentiated into squamause epithelium and affected normal development and obstructed the fusion of mouse palatal shelves. CONCLUSION: The results of histological observation indicate that dexamethasone promotes the proliferation of palatal meseuchymal cells and inhibits the normal differentiation of palatal medial edge epithelial cells, which results in cleft palate.

Animals↗

[Characteristics of nerve root compression caused by degenerative lumbar stenosis with scoliosis].

OBJECTIVE: To investigate the factors that may contribute to radiculopathy in degenerative lumbar stenosis with scoliosis (DLSS) and their association with the pattern of the scoliosis. METHODS: Twenty-seven patients with DLSS were examined in our hospital. The symptomatic nerve roots were determined by pain distribution, and neurological findings. The compressive factors were diagnosed by magnetic resonance imaging and myelography or radiculography. The pattern of scoliosis was determined by plain radiographs. Correlation between the affected nerve root and the compressive factors or the pattern of the scoliosis were then analyzed. RESULTS: Among the 27 patients, L3 root was affected in 6 patients, L4 root in 13 patients, L5 root in 15 patients, and S1 root in 9 patients. L3 and L4 roots were more compressed by foraminal or extraforaminal stenosis on the concave side of the curve, whereas L5 and S1 roots were commonly affected by lateral recess stenosis on the convex side. CONCLUSION: In DLSS, nerve root compression is not only seen on the concave side of the scoliosis, but also equally involved on the convex side. Most radiculopathy in DLSS distributes close to central sacral vertical line, which may be due to the abnormal weight-bearing for the pattern of scoliosis.

Aged↗

[Fragment length polymorphism of Wx-B1 gene digested by BamHI and its relation to amylose content of wheat].

There are two types of starch, amylose and amylopectin of flour. Amylose content (AC) is significantly negatively correlated with noodle quality. The waxy gene (Wx) encodes the granule-bound starch synthase (GBSS, EC 3.4.1.11), or Wx protein, is responsible for the synthesis of amylose in wheat. Common wheat is allohexaploid, it has three different Wx proteins: Wx-A1, Wx-B1, and Wx-D1. Consequently, amylose content and pasting properties of starch were influenced by the lack of the Wx-B1 protein, followed by that of Wx-D1, and Wx-A1. Using STS (sequence-tagged sites) primers, the sequences were amplified near the 4th intron region, and fragments amplified were digested by BamHI in 35 wheat cultivars. The results indicate that some fragments can be digested and the other cannot. The fragments digested showed two length polymorphism, and the length is negatively correlated with amylose content. The fragment in many cultivars with amylose content above 20% can be digested by BamHI, while those with amylose content below 20% cannot. All these indices demonstrate that there is variation exists in amplified region of Wx-B1 gene. This can be useful in breeding program to select wheat cultivars with different amylose content, and improve wheat quality.

Amylose↗

[Improving the affinity of an anti-TNF-alpha scFv by random mutation].

AIM: To improve the affinity of an anti-TNF-alpha scFv. METHODS: A mutant phage antibody library derived from an anti-TNF-alpha scFv gene was generated by error-prone PCR. The mutated genes were then subjected to DNA shuffling. Mutants with improved affinity were selected by bio-panning. Affinity improvement of the selected mutants was verified by dot blot ELISA and thiocyanate elusion ELISA. RESULTS: One mutant was obtained with relative affinity index (1.37 mol/L) higher than that of the parent scFv (0.48 mol/L). CONCLUSION: Error-prone PCR plus DNA shuffling is effective in improving the affinity of antibodies.

Amino Acid Sequence↗

[The expression of TGF-beta1 and bFGF after LASEK and the effects of 20% ethanol exposure on corneal wound healing].

OBJECTIVE: To assess the effects of 20% ethanol used in LASEK on corneal wound healing. METHODS: Forty-eight eyes from 24 rabbits were deepithelialized by two techniques. The epithelium were detached with either 20% ethanol (applied for 30 seconds) or mechanical scraping, then ablated was performed. The number of superficial stromal keratocytes was counted and the morphologic changes were observed. Expression of TGF-beta1 and bFGF mRNAs was detected and analyzed by reverse transcription-polymerase chain reaction and immunocytochemical methods at 1, 7, 30 and 90 days after the surgery. RESULTS: One day after the surgery, the expression of TGF-beta1 and bFGF in the keratocytes in both treated groups was lower than that of the normal controls. Seven days after the surgery, the expression of TGF-beta1 and bFGF in both treated groups was greater than that of the normal controls (P < 0.01). The expression in the alcohol-treated group was greater than that of the surgical-treated group (P < 0.01). The expression of TGF-beta1 and bFGF reached the peak 30 days after the surgery, no significant difference was detected between the alcohol-treated and surgical-treated groups. There was no significant difference in expression level between the alcohol-treated and surgical-treated groups 3 months after the surgery; as well as between treated groups and normal group. The amount of TGF-beta1 and bFGF mRNA was positively correlated with the number of keratocytes. The correlation coefficient between TGF-beta1 and bFGF mRNA and the number of the keratocytes was 0.744 (P < 0.01) and 0.738 (P < 0.01) in the alcohol-treated group; and was 0.664 (P < 0.01) and 0.785 (P < 0.01) in the surgical-treated group, respectively. CONCLUSIONS: The expression of TGF-beta1 and bFGF mRNA undergo a dynamic process of "decrease-increase-normal". Although ethanol has a slight toxic effect on rabbit epithelial cells, but the effects do not persist over time, therefore, it is relatively safe to use the alcohol treatment in the LASEK.

Animals↗

[Determination of the writing age of blue ballpoint ink by gas chromatography].

A method of identifying the writing age of blue ballpoint ink has been established for imperative demand of forensic laboratory. The content of the volatile component in blue ballpoint ink was determined by gas chromatography (GC). The absorbance of the dye in the blue ballpoint ink was measured by ultraviolet-visible spectrometry (UV-Vis). A writing age curve of the blue ballpoint ink has been established by the ratio of the content of the volatile components and the dye, based on the identification of 74 kinds of blue ballpoint inks, from both domestic and international origins. The change of benzyl alcohol or phenoxyethyl alcohol was tested with the writing age. Blue ballpoint inks of different kinds were detected and the repeatability of the experiment was investigated. The results indicated that the method is reliable and systematic, and especially suitable for practical cases.

Benzyl Alcohol↗

[ISGF3, a critical factor of the IFN-alpha pathway in the antiviral action of HBV].

OBJECTIVE: To study the mechanism of signal transduction in anti-HBV action of IFN-alpha. METHODS: The HBV DNA in HepG 2.2.15 cell line supernatant with/without IFNalpha-2b were monitored by fluorescence real-time quantitive PCR. STAT1, STAT2, ISGF3-gamma, PKR, 2'5'-OAS mRNA levels from HepG 2 and HepG 2.2.15 cell lines that were treated with/without IFNalpha-2b at different times were detected by semi-quantitive RT-PCR. And the ISGF3-gamma protein was detected by Western blot. Then, these items were detected again after inhibiting the JAK-STAT pathway with genistein. RESULTS: The HBV DNA in 2215 supernatant that were treated with IFNalpha-2b for 8 hours decreased 0.72 log 10 copies/ml. But the basal levels of DNA in cells pretreated with genistein? followed by IFNalpha-2b did not decrease. The STAT1, STAT2, ISGF3-gamma, 2'5'-OAS, PKR mRNA levels were upregulated by IFNalpha-2b. The same phenomena were observed with STAT1, STAT2, ISGF3-gamma mRNA when pretreated with genistein then treated with IFNalpha-2b, but the levels of 2'5'-OAS, PKR mRNA were decreased in this situation. The expression of the protein of ISGF3-gamma was also augmented by IFNalpha-2b, and was blocked by genistein. CONCLUSION: The JAK-STAT pathway seems to be a critical pathway in IFNalpha-2b action against HBV? and ISGF3 is most probably a key factor of the route.

Antiviral Agents↗

[Application of freeze-dried cancellous allograft in treatment of spinal tuberculosis].

OBJECTIVE: To investigate the efficacy of freeze-dried cancellous allograft in the treatment of spinal tuberculosis. METHODS: From January 1999 to August 2004, there were 31 cases of spinal tuberculosis who underwent surgery. The freeze-dried cancellous allograft was used as grafting material in all the cases. The cancellous allograft was packed in a titanium mesh cage or an artificial vertebrae, and then used as a strut graft anteriorly to implant into the bone defect after the radical debridement, and the instrumentation was done. RESULTS: Twenty-three cases were followed up 1.5 years to 5 years (3.7 years on average), and bony fusion was achieved in 21 cases 6 months later. In 2 cases ceasing antituberculous therapy after 2 months of operation, the local recurrence was obvious. The loosened screw was noticed in one of these two cases, who had tuberculosis in lumbar spine. When antituberculous therapy continued, the bony fusion was observed in these two cases 12 months later. No further position change of the instrument was noticed in the patient carrying loosened screw, but the kyphosis of the thoracolumbar spine aggravated. CONCLUSION: Freeze-dried cancellous allograft could be used in the treatment of spinal tuberculosis. To achieve good results of allograft incorporation and remodeling, the rigid instrumentation should be performed, postoperative antituberculous therapy is also important.

Adolescent↗