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Xi-qiang Yang

Publications and source records attributed to Xi-qiang Yang.

14 recordsLinked to original sources
PubMed2006

[Clinical analysis of 942 cases of Kawasaki disease].

OBJECTIVE: The study was designed to investigate the clinical characteristics and the effects of therapeutic proposal on Kawasaki disease (KD). METHODS: Clinical features, diagnosis and treatment for totally 942 patients with KD hospitalized during Jan, 2000 to Dec, 2004 were reviewed. Clinical features of typical and incomplete KD were compared. Also, influential factors for KD resistant to intravenous immune globulin (IVIG) therapy were analyzed. Five hundred and ten cases were followed up for analyzing the prognosis of coronary artery lesion (CAL). RESULTS: (1) 774 cases were diagnosed as typical KD, and 168 cases as incomplete KD. The incidence of infants with incomplete KD was higher than that of infants with typical KD (18.5% vs. 10.1%, P < 0.01). As compared with typical KD, the cases of incomplete KD had a long duration of fever before final diagnosis [(7.7 +/- 2.9) d vs. (7.0 +/- 2.4) d, P < 0.01], high hemoglobin level [Hb, (106.6 +/- 13.4) g/L vs. (103.5 +/- 12.3) g/L, P < 0.01], high hematocrit [Hct, (32.0 +/- 4.3)% vs. (31.0 +/- 4.0)%, P < 0.01], and high prevalence of CAL (23.8% vs. 16.8%, P < 0.05), respectively. The occurrence rate and emerging time of clinical manifestations in incomplete KD and in typical KD were presented, respectively: non-exudative conjunctivitis [occurrence rate, 64.9% vs. 93.5%; emerging time, (4.4 +/- 1.4) d vs. (4.0 +/- 1.6) d, respectively (P < 0.05 or P < 0.01)], erythema and cracking of lips [occurrence rate, 50.6% vs. 94.8%; emerging time, (4.9 +/- 1.4) d vs. (4.5 +/- 1.6) d, respectively (P < 0.05 or P < 0.01)], rash [occurrence rate, 35.1% vs. 87.7%; emerging time, (3.9 +/- 1.9) d vs. (3.4 +/- 1.7) d, respectively (P < 0.05 or P < 0.01)], erythema and edema of extremity [occurrence rate, 26.8% vs. 71.4%; emerging time, (6.7 +/- 1.5) d vs. (5.3 +/- 1.7) d, respectively (P < 0.01)], cervical lymphadenopathy [occurrence rate, 34.5% vs. 68.0%; emerging time, (4.3 +/- 2.5) d vs. (3.6 +/- 2.2) d, respectively (P < 0.05 or P < 0.01)], strawberry tongue [occurrence rate, 31.0% vs. 59.8%; emerging time, (5.6 +/- 2.2) d vs. (4.9 +/- 1.8) d, respectively (P < 0.05 or P < 0.01)], membranous desquamation of fingertips [occurrence rate, 34.5% vs. 56.3%; emerging time, (11.7 +/- 3.3) d vs. (10.3 +/- 2.7) d, respectively (P < 0.01)], and desquamation peri-anus [occurrence rate, 42.9% vs. 50.0%; emerging time, (6.7 +/- 2.7) d vs. (6.9 +/- 2.5) d, respectively (P > 0.05)]. Except for peri-anus desquamation, other clinical manifestations in incomplete KD were sporadical as compared to typical KD. (2) Six per cent (51/857) of cases were resistant to the IVIG therapy. As compared to the group responding to IVIG therapy, high prevalence of CAL (31.4% vs. 17.1%, P < 0.05), long fever duration [(10.6 +/- 3.9) d vs. (7.5 +/- 2.3) d, P < 0.01], low Hb level [(99.9 +/- 14.1) g/L vs. (104.3 +/- 12.4) g/L, P < 0.01], low Hct [(30.1 +/- 4.5)% vs. (31.2 +/- 4.0)%, P < 0.05], low platelet [PLT, (256.9 +/- 142.4) x 10(9)/L vs. (309.7 +/- 131.5) x 10(9)/L, P < 0.05], and low albumin level [ALB, (27.8 +/- 8.4) g/L vs. (33.5 +/- 6.7) g/L, P < 0.01] were found in the group resistant to IVIG therapy, respectively. (3) In patients who received IVIG 1 g/kg and 2 g/kg, the recovery rates from CAL were 83.1% and 89.7% (P > 0.05), respectively. The prevalence of CAL in those without CAL in acute and subacute stages was 0.9% and 3.5% (P > 0.05), respectively, during 2 year-follow-up period. CONCLUSION: (1) Infants appeared to have more chances to suffer from incomplete KD. Incomplete KD had high prevalence of CAL. The peri-anus desquamation might be an important clue for early diagnosis of incomplete KD. (2) In acute stage, the influential factors for KD resistance to IVIG therapy included prolonged fever, non-elevated PLT, and persistent decrease in Hb, Hct and ALB levels. (3) Children receiving IVIG 1 g/kg and 2 g/kg had the similar effects on recovery and prevention from CAL within the first two years after KD onset.

Adolescent↗
PubMed2006

[Combined effects of neonatal Bacillus Calmette-Guerin vaccination and respiratory syncytial infection on experimental asthma in mice].

OBJECTIVE: Neonatal Bacillus Calmette-Guerin (BCG) vaccination could decrease asthma prevalence in human according to "hygiene hypothesis". The authors proposed a hypothesis that effect of BCG vaccination on inhibiting asthma in human might be reversed by respiratory virus infection. The objective of this study was to observe combined effects of neonatal BCG vaccination and respiratory syncytial virus (RSV) infection on experimental asthma in mice. METHODS: Neonatal BALB/c mice were divided into five groups. Control and ovalbumin (OVA) groups were mock-vaccinated at birth and mock-infected at 3 weeks of age. BCG + OVA group was BCG-vaccinated and mock-infected. RSV + OVA group was mock-vaccinated and RSV-infected. BCG + RSV + OVA group was BCG-vaccinated and RSV-infected. Except for control group, all the other groups underwent ovalbumin (OVA) sensitization and challenge. Airway responsiveness to inhaled methacholine was measured and bronchoalveolar lavage (BAL) was performed after the last challege. Cells in BAL fluid (BALF) were counted. Cytokines in BALF and serum OVA-specific IgE were detected by ELISA and inflammatory characteristics of lungs was scored by staining with hematoxylin and eosin. RESULTS: (1) The numbers of total white cells, lymphocytes, monocytes, neutrophils, and eosinophils in the BALF from all OVA-sensitized/challenged groups were significantly greater than those in control (P < 0.01), and BCG + OVA group had significantly lower total white cells, lymphocytes and eosinophils as compared with other OVA-sensitized/challenged groups (P < 0.05 or 0.01). (2) All OVA-sensitized/challenged groups had significantly lower IFNgamma (P < 0.05) and higher IL-4 (P < 0.05) level in BALF as compared with control, but there was no significant difference among all OVA sensitized/challenged groups. There was no significant difference in IL-10 level between all experimental groups. (3) All OVA-sensitized/challenged groups showed significantly higher serum OVA-specific IgE titers than control (P < 0.05 or 0.01), but no significant difference was found among all OVA sensitized/challenged groups. (4) RSV + OVA and BCG + RSV + OVA groups displayed the highest airway resistance and subsequently in order as follows: OVA group, BCG + OVA group and control group in severity of airway hyperreactivity (AHR), but no significant difference was found between RSV + OVA and BCG + RSV + OVA groups. (5) Histological score of peribronchiolitis, perivasculitis, alveolitis, and peribronchial eosinophilia in all OVA-sensitized/challenged groups was significantly higher than that in control. BCG + OVA group had significantly milder peribronchiolitis and peribronchial eosinophilia than the other OVA-sensitized/challenged groups (P < 0.05) and significantly milder alveolitis than OVA and BCG + RSV + OVA groups (P < 0.05). CONCLUSION: Neonatal BCG vaccination decreased asthmatic inflammation and AHR and RSV infection could reverse anti-asthma effect of neonatal BCG vaccination in OVA-sensitized/challenged mouse model.

Animals↗
PubMed2005

[Effects of Bacillus Calmette-Guerin vaccination on immune functional development of splenic T cell in neonatal mice].

OBJECTIVE: Almost every neonate receives Bacillus Calmette-Guerin (BCG) vaccination in China. The authors' previous study showed that BCG promoted cord blood monocyte-derived dendritic cells maturation and induced high level of interleukin (IL)-10, medium level of interferon (IFN)-gamma, but low level of IL-4 production by cord naive T cells. The experiments in the present study were designed to explore the effects of neonatal BCG vaccination on immune functional development of splenic T cells in mice in vivo. METHODS: Neonatal BALB/c mice were inoculated with BCG intraperiotoneally. Four weeks later, spleen cells of mice were isolated and surface molecular markers of CD4, CD25 and CD44 and intracellular IFN-gamma, IL-10, and IL-4 in CD3(+) T cells were detected by flow cytometry. Furthermore, mRNA expression of transcription factor T-bet, Foxp3 and GATA-3 were analyzed by RT-PCR. RESULTS: The percentage of total CD4(+) T cells decreased [(23.50 +/- 2.59)% vs. (47.38 +/- 10.41)%, P < 0.01] but the percentage of CD25(+) [(24.92 +/- 2.74)% vs. (20.27 +/- 2.85)%, P < 0.05] and CD44(+) [(89.29 +/- 2.56)% vs. (82.98 +/- 5.51)%, P < 0.05] T cells in CD4(+) T cells was higher in BCG-vaccinated mice than that in controls. Meanwhile, the percentage of IFN-gamma positive [(6.52 +/- 2.40)% vs. (3.13 +/- 2.03)%, P < 0.05] and IL-10 positive [(14.81 +/- 3.65)% vs. (10.90 +/- 1.61)%, P < 0.05] but not IL-4 positive [(1.17 +/- 0.46)% vs (1.51 +/- 0.75)%, P > 0.05] cells in CD3(+) T cells of BCG-vaccinated mice was significantly higher than that of non-BCG-vaccinated mice. In comparison with BCG-naive mice, T-bet was significantly high in BCG-vaccinated mice [T-bet/beta-actin 0.44 +/- 0.11 vs. 0.28 +/- 0.06, P < 0.05], but there was no significant difference in GATA-3 [GATA-3/beta-actin 0.46 +/- 0.08 vs. 0.50 +/- 0.10,P > 0.05] and Foxp3 [Foxp3/beta-actin vs. 0.27 +/- 0.11 and 0.30 +/- 0.16, P > 0.05] mRNA expression between the two groups. CONCLUSION: Neonatal BCG vaccination could induce strong Th1 but weak Th2 response as reported previously. Though neonatal BCG vaccination was not capable of inducing CD4(+)CD25(+) regulatory T cell response with Foxp3 expression, it caused increase of IL-10(+) CD3(+) cells which might represent some regulatory T cells producing IL-10.

Animals↗
PubMed2005

[Construction and effect of the recombinant pshRNA plasmid against respiratory syncystial virus M2-1 gene].

OBJECTIVE: Respiratory syncystial virus (RSV) is the most common cause of lower respiratory infections in infants worldwide. There is no reliable vaccine or antiviral drug against RSV at present. RNA interference (RNAi) technology is a potent method to degrade expression of the cognate mRNA. In order to inhibit the replication of RSV at gene level, the effects of specific RNAi against M2-1 gene of RSV on inhibition of viral replication in cell culture system was observed in this study. METHODS: RSV M2-1 gene, which plays a key role in RSV transcription, was chosen in this study and was used as target gene and recombinant plasmid pshRNA7816 targeting the mRNA of RSV M2-1 gene coding sequence was constructed. The pshRNA7816 was transfected into Hep2 cells. The effects of the pshRNA7816 on changes of cytopathogenic effect (CPE) of Hep2 cell induced by RSV infection were observed microscopically. Viral plaque forming assay and MTT assay were used to detect the viral titer change and protective function of the pshRNA7816 on RSV infected Hep2 cell. RESULTS: The recombinant RNAi plasmid pshRNA7816 which targets the mRNA of RSV M2-1 gene was successfully constructed. The pshRNA7816 significantly reduced CPE of RSV infected Hep2 cells, reduced the viral titer of RSV in the cells (P < 0.001). The pshRNA7816 raised the survival rate of RSV infected Hep2 cells (P < 0.001). Non-specific pshRNA plasmid did not show anti-RSV effects (P > 0.05). CONCLUSION: The recombinant pshRNA7816 plasmid which targeted the mRNA of RSV M2-1 gene showed a significant and specific anti-RSV effect.

Hep G2 Cells↗
PubMed2004

[Expression of CD 86 on monocyte and B cell surface, the level of T(H)-derived cytokine and their correlation in children with asthma].

OBJECTIVE: To explore the role of T lymphocytes activation co-stimulation pathway and T lymphocyte subset activation in asthma pathogenesis. METHODS: The blood samples were taken from 35 asthma children (including 22 male and 13 female, age 11 months-9 years) and 31 normal children (including 19 male and 12 female, age 8 months-12 years). Direct immunofluorescence flow cytometry was used to detect the CD86 mean fluorescence intensity (MFI) on CD(14)(+) cell, CD(19)(+) cell percentage and CD19 and CD86 double positive cell percentage in PBMC activated by LPS. ELISA was used to detect the levels of IL-4, IL-13, IFN-gamma in culture supernatants of PBMC stimulated with PHA and plasma total IgE level. RESULTS: (1) The CD86 MFI on CD(14)(+) cell in asthma group was elevated significantly (31.8 +/- 9.2 vs 23.5 +/- 6.4, P < 0.01). (2) CD(19)(+) cell percentage and CD19 and CD86 double positive cell percentage in PBMC stimulated with LPS in asthma group were increased significantly (13.5 +/- 4.0 and 4.6 +/- 2.0 vs. 8.2 +/- 3.0 and 2.3 +/- 1.4, respectively, P < 0.01). The plasma total IgE level [186.6 (64.3 - 723.6)] was higher than that of control's [41.95 (0.9 - 115.2)]. (3) The levels of IL-4 and IL-13 in supernatants stimulated with PHA increased significantly [34.2 (2.8 - 70.0) and 1 239.0 (378.3 - 2 929.0) vs. 9.7 (2.0 - 46.2) and 683.2 (128.8 - 1 560.8) respectively, P < 0.01, P < 0.05]; and the level of IFN-gamma decreased significantly [12.16 (1.6 - 44.8) vs. 26.7 (2.1 - 99.5) P < 0.05]. (4) In asthma group there was a significantly positive correlation of CD86 MFI on CD(14)(+) cell with CD19 and CD86 double positive cell percentage (r = 0.644), there was a significantly positive correlation of CD(19)(+)CD(86)(+)cells percentage with plasma total IgE (r = 0.537); there was a significantly positive correlation of CD(19)(+)cells percentage with the levels of IL-4 and IL-13 (r = 0.607, 0.540 respectively); a significantly positive correlation of CD(19)(+)CD(86)(+) percentage cells with the levels of IL-4 and IL-13 was found (r = 0.617, 0.678, respectively). CONCLUSIONS: (1) The expression of CD86 on APC cells increased in children with acute asthma. (2) The response to mitogens of B lymphocyte and T(H2) but not T(H1) lymphocyte were increased significantly. The results suggest that CD86 and imbalance of T(H) subset may play an important role in asthma pathogenesis.

Antigens, CD↗
PubMed2004

[Role of dendritic cells in the pathogenesis of asthma in children].

UNLABELLED: Dendritic cells (DC) are very potent antigen-presenting cells (APC) with a unique ability to activate naive T cells to induce the differentiation of TH1/TH2. Monocytes can develop into DC in the presence of different cytokines such as granulocyte-macrophage colony-stimulating factor (GM-CSF) and IL-4. DCs are thought to play a key role in the initiation and maintenance of T cell immunity to inhaled antigens. While the density of DC within the bronchial mucosa is increased in asthma, there is little information currently available concerning the effects of DC in asthmatic children. OBJECTIVE: To investigate the role of dendritic cells in the pathogenesis of acute attack of asthma in children. METHODS: Thomas' method was adopted. The adherent precursors of DC were isolated from peripheral blood of asthmatic children in acute attack stage and healthy controls. The adherent cells were induced with granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-4 (IL-4) and tumor necrosis factor-alpha (TNF-alpha) to DC in vitro. The expression of the surface molecules CD80, CD86, HLA-DR etc. on the DC was examined by fluorescent activated cell sorter (FACS). And the ability to secret IL-10, IL-12 and their potentials to stimulate the proliferative reaction of DC inductive self T- lymphocyte were observed. RESULTS: The results showed that in asthmatic children's acute attack stage, self T- lymphocyte proliferative reaction induced by DC was remarkably increased compared with normal control subjects (P < 0.01). At the same time, the asthmatic children in acute attack stage had remarkably decreased the ability to secret IL-10 compared with normal control subjects (P < 0.01), while the ability to secret IL-12 remarkably decreased compared with normal control subjects (P < 0.01); meanwhile, the HLA-DR and co-stimulating factor CD86(B(7-2)) expressed by DCs remarkably increased in the asthmatic children in acute attack stage compared with normal control subjects (P < 0.01). CONCLUSION: DC possibly plays a vital role in the immunological mechanism of asthma by means of inducing the differentiation of TH1/TH2, that is DC may be the key factor in initiating the airway allergic reaction and the possible mechanism may involve interleukins (especially IL-10 and IL-12, etc.) secreted by DCs.

Adolescent↗
PubMed2003

[Identification of two novel WASP gene mutations in 3 boys with Wiskott-Aldrich syndrome].

OBJECTIVE: The Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency caused by mutations in the WAS protein (WASP) gene. The disease is characterized by recurrent infections, eczema, and thrombocytopenia with small platelets, and it is known to be associated with extensive clinical variability, and mutation studies indicated that genotypes are also highly variant among WAS patients. The present study was conducted to identify the mutation types of Wiskott-Aldrich syndrome protein (WASP) gene in 3 boys suffering from Wiskott-Aldrich syndrome. METHODS: Based on the typical clinical manifestations of Wiskott-Aldrich syndrome including thrombocytopenia, eczema, and recurrent infections and scanning electron micrographs, 3 patients were suspected of having WAS. The WASP gene of the 3 patients and their mothers were detected by PCR-direct sequencing analysis. RESULTS: By sequence analysis using sense and antisense primer separately, the authors found two novel WASP gene mutations. For the twin brothers, a C deletion at nucleotide 984 was detected in exon 10 of WASP gene (984delC). The consequence of the C deletion involved frameshift mutation after H317 and premature stop at 444 (H317fsX444). Their mother was a carrier of the mutated WASP gene. For another WAS patient, a nonsense mutation with nucleotide substitution of G to T at position 1388 (1388G-->T) in exon 11 of WASP gene, led to premature translational termination at amino acid position 452 (E452X). His mother had not been found to have WASP gene mutation. CONCLUSION: Genetic analysis is useful in definite diagnosis of Wiskott-Aldrich syndrome patients and in carrier detection and prenatal diagnosis, especially of atypical or sporadic WAS patients.

Blood Platelets↗
PubMed2003

[Inhibition of respiratory syncytial virus replication in cultured cells by RNA-cleaving DNAzyme].

OBJECTIVE: DNAzyme/Deoxyribozyme is another novel molecular biological tool following the ribozyme. DNAzyme consists of a 15-nucleotide (nt) internal loop as its catalytic domain and two flanking substrate-recognition domains of 7 to 8 nt each which is complementary to substrate. The RNA substrate is cleaved at a particular phosphodiester located between an unpaired purine and a paired pyrimidine residue. DNAzyme has been applied in fields such as viral infectious disease, tumor, cardiovascular disease and genetic disease. But there is no report about using DNAzyme for anti-respiratory syncytial virus purpose. To observe the inhibitory effects of RNA-cleaving DNAzymes on respiratory syncytial virus (RSV) replication in cultured cells. METHODS: Anti-RSV RNA-cleaving DNAzyme DZ604 was designed to target the RSV genome at the start of the NS2 gene in an effort to inhibit the RNA replication. Microscope and electron microscope were used to observe the effects of anti-RSV genomic RNA DNAzyme on cytopathogenic effect (CPE) and ultrastructural change of 9HTE cell induced by RSV infection. Viral plaque forming reduction assay and MTT assay were used to detect the anti-RSV activity and protective function for RSV infected 9HTE cells of DNAzyme. RESULTS: Anti-RSV genomic RNA DNAzyme (DZ604) significantly improved CPE of RSV-infected 9HTE cells. The time to appearance of CPE and of total CPE was delayed by using DZ604 in a dose-dependent manner. At a 5 micro mol/L concentration of DZ604, CPE of 9HTE cells induced by RSV infection at 10 and 1 multiplicity of infection (MOI) was not improved. At smaller MOI (0.1, 0.01, 0.001, 0.0001) of RSV infection, CPE of 9HTE cells was significantly lightened by DZ604 at the same concentration. DZ604 also significantly improved ultrastructural change of 9HTE cells at early stage of RSV infection. Reduction in RSV yield was 85.56% and 8.33% at concentrations of 5 micro mol/L and 0.25 micro mol/L of DZ604. DZ604 inhibited RSV yield in a dose-dependent manner (P < 0.05). Non-specific DNAzyme did not have anti-RSV activity (P > 0.05). CONCLUSION: Anti-RSV genomic RNA DNAzyme designed and synthesized in our laboratory was capable of inhibiting respiratory syncytial virus replication specifically in cultured cells. Our data indicated that DNAzymes could be useful for the prevention against respiratory syncytial virus infection.

Animals↗