Ox-LDL induces dysfunction of endothelial progenitor cells via activation of NF-κB.

Dyslipidemia increases the risks for atherosclerosis in part by impairing endothelial integrity. Endothelial progenitor cells (EPCs) are thought to contribute to endothelial recovery after arterial injury. Oxidized low-density lipoprotein (ox-LDL) can induce EPC dysfunction, but the underlying mechanism is not well understood. Human EPCs were cultured in endothelial growth medium supplemented with VEGF (10 ng/mL) and bFGF (10 ng/mL). The cells were treated with ox-LDL (50 µg/mL). EPC proliferation was assayed by using CCK8 kits. Expression and translocation of nuclear factor-kabba B (NF-κB) were evaluated. The level of reactive oxygen species (ROS) in cells was measured using H2DCF-DA as a fluorescence probe. The activity of NADPH oxidase activity was determined by colorimetric assay. Ox-LDL significantly decreased the proliferation, migration, and adhesion capacity of EPCs, while significantly increased ROS production and NADPH oxidase expression. Ox-LDL induced NF-κB P65 mRNA expression and translocation in EPCs. Thus ox-LDL can induce EPC dysfunction at least by increasing expression and translocation of NF-κB P65 and NADPH oxidase activity, which represents a new mechanism of lipidemia-induced vascular injury.

Factors associated with decision time for patients with ST-segment elevation acute myocardial infarction.

Increased delay in visiting a hospital for patients with ST-segment elevation myocardial infarction (STEMI) is often associated with poor outcomes. The factors associated with the decision time were analyzed by comparing the characteristics of patients with delays longer or shorter than the median of 60 min. Pre-hospital delay tended to be longer for patients living in suburban areas compared to those in urban areas (P=0.015). Shorter decision time was more likely among older patients. Being married, medical insurance coverage, and the level of educational qualification did not affect decision time. More efforts should be paid to educate the patients with high risk in suburban areas in order to effectively reduce pre-hospital delays.

[The change of transient receptor potential vanilloid-1 and interleukin-1α in periodontal tissue during experimental tooth movement].

PURPOSE: To investigate the expression of TRPV1 and IL-1α in Sprague-Dawley rats' periodontal ligament (PLD) during experimental tooth movement of different orthodontic force and duration, and explore the role of TRPV1 and IL-1α in orthodontic pain. METHODS: 66 Sprague-Dawley rats were divided into control group (n=6), sham operation group (n=6) and experimental group (n=54) randomly. Orthodontic force was applied on right first maxillary molar in rats and the changes of TRPV1 and IL-1α expression were detected by real-time PCR at 4 h, 8 h, 1 d (three subgroups were added according to different forces: 1 d-30 g, 1 d-50 g, 1 d-80 g ), 3 d, 5 d, 7 d, 14 d after tooth movement. The data was analyzed using SPSS 13.0 software pakage. RESULTS: Following the experimental tooth movement, the expression of TRPV1 and IL-1α in periodontal tissues were significantly up-regulated from 4 h to 7 d, with a peak at 1 d and returned to normal level at 1 week. The greater force applied during experimental tooth movement at 1 d, the higher expression of TRPV1 and IL-1α were detected in periodontal tissues. CONCLUSIONS: Experimental tooth movement leads to regular change of TRPV1 and IL-1α expression in periodontal tissues, which indicates that TRPV1 and IL-1α may play an important role in orthodontic pain.

[The change of calcitonin gene- related peptide in periodontal tissue during orthodontic tooth movement].

PURPOSE: To establish a Sprague-Dawley rat model of tooth movement, detect the expression of calcitonin gene-related peptide (calcitonin gene related peptide, CGRP) in Sprague-Dawley rats' periodontal tissues during tooth movement and explore the role of the peripheral mechanisms of pain in orthodontics. METHODS: 60 Sprague-Dawley rats were randomly divided into experimental group (n=54) and control group (n=6). Force was applied on right maxillary first molar in rats and the changes of CGRP expression were detected by real-time PCR 4 h, 8 h, 1 d, 3 d, 5 d, 7 d, 14 d after tooth movement. SPSS 13.0 software package was selected and one-way ANOVA (least significant difference, LSD) was used for statistics analysis. RESULTS: Experimental tooth movement led to an increase in the expression of CGRP. In addition, following experimental tooth movement, the expression of CGRP in periodontal tissues was significantly up-regulated from 4 h, with a peak on 1d and returned to the control level at 2-week. 1 d after experimental tooth movement, the application of different forces to rats induced a significant increase in CGRP expression. CONCLUSION: The regular change of CGRP expression in periodontal tissues indicates that CGRP may play an important role in peripheral mechanism of orthodontic pain.

[Construction and identification of BIRC5 shRNA lentiviral expression vector].

AIM: Design and synthesis complementary DNA sequences of 3 pairs of short hairpin structure and a pair of negative control sequence by RNA interference technique and construct and identify a lentiviral interference vector with human BIRC5 gene as target gene. METHODS: The designed and synthesised Single-Stranded primer were annealed to Double-Stranded oligo sequences and subcloned into linear pMAGic lentiviral plasmid vector digested by enzyme Age I and EcoR I. Screening positive clone after transformed into DH5α competent cells and identified by PCR amplification and DNA sequencing. RESULTS: 335 bp straps of positive clone and 298 bp straps of negative clone form PCR amplification production have been obtained after gel electrophoresis, the designed and synthesised sequences have been contained in these clone straps confirmed by the result of DNA sequencing. CONCLUSION: Four pairs of BIRC5 shRNA recombinant lentiviral expression vector were constructed successfully, which laid the foundation for researching the inhibition of BIRC5 siRNA target against tumor cells proliferation, induction apoptosis and gene therapy.

[Clinical and experimental retrospective analysis on acute leukemia with trisomy 4 cell].

OBJECTIVE: To explore the clinical and experimental features of acute leukemia (AL) with trisomy 4. METHODS: A retrospective analysis on the clinical and laboratory data of 21 cases of AL with trisomy 4 was performed. Chromosomes were prepared using direct method and/or short-term (24 h) cultures of bone marrow cells. Karyotypic analysis was carried out by using R-banding technique. Thirteen cases were studied by interphase fluorescence in situ hybridization (FISH) by using a chromosome 4-specific alpha -satellite DNA probe labeled by spectrum Green to ascertain the presence of a clone with trisomy 4. Five cases with t (8; 21) revealed by karyotypic analysis were detected by dual-color FISH using t (8; 21) translocation probe to confirm the AML1/ETO rearrangement. RESULTS: All the patients with AL and trisomy 4 were with de novo AL except two cases with secondary AL. M2 was the most frequent Franch-American-British(FAB) subtype in this series (9/21 cases). The initial leukocyte count more than 10x 10(9)/L was seen in 16 cases. An enlargement of liver, spleen and/or lymph nodes in varying degrees was found in 15 cases. Among 15 cases received immunophenotypic analysis, 11 cases showed CD34 positivity and 6 cases co-expressed myeloid and lymphocyte antigens. Karyotypic analysis disclosed clonal trisomy 4 in 18 cases and one cell with +4 in 3 cases. Isolated trisomy 4 was found in 7 cases, while 14 cases had other abnormalities besides trisomy 4 among which t (8; 21) was found in 8 cases. Dual-color FISH confirmed that all 13 cases including 3 cases having one cell with +4 on karyotypic analysis had clonal trisomy 4. Dual-color FISH confirmed that all 5 cases with t (8; 21) had AML1/ETO rearrangement. CONCLUSION: AL patients with trisomy 4 have unique clinical and experimental features and a poor prognosis.

H(1) and H(2) receptors in the locus ceruleus are involved in the intracerebroventricular histamine-induced carotid sinus baroreceptor reflex resetting in rats.

Objective To investigate the role of H(1) and H(2) receptors in the locus ceruleus (LC) in carotid sinus baroreceptor reflex (CSR) resetting induced by intracerebroventricular (i.c.v.) injection of histamine (HA). Methods The left and right carotid sinus regions were isolated from the systemic circulation in 18 male Sprague-Dawley rats anesthetized with pentobarbital sodium. The intracarotid sinus pressure (ISP) was altered in a stepwise manner in vivo. ISP-mean arterial pressure (MAP) relationship curve and its characteristic parameters were constructed by fitting to the logistic function with five parameters. The changes in CSR performance induced by i.c.v. HA and the effects of pretreatment with H(1) or H(2) receptors selective antagonist, chlorpheniramine (CHL) or cimetidine (CIM) into the LC, on the responses of CSR to HA were examined. Results I.c.v. HA (100 ng in 5 mu l) significantly shifted the ISP-MAP relationship curve upwards (P < 0.05) and obviously decreased the value of the reflex parameters such as MAP range and maximum gain (P < 0.05), but increased the threshold pressure, saturation pressure and ISP at maximum gain (P < 0.05). The pretreatment with CHL (0.5 mu g in 1 mu l) or CIM (1.5 mu g in 1 mu l) into the LC could obviously attenuate the changes mentioned above in CSR performance induced by HA, but the alleviative effect of CIM was less remarkable than that of CHL (P < 0.05). Respective microinjection of CHL or CIM alone into the LC with the corresponding dose and volume did not change CSR performance significantly (P > 0.05). Conclusion Intracerebroventricular administration of HA results in a rapid resetting of CSR and a decrease in reflex sensitivity, and the responses of CSR to HA may be mediated, at least in part, by H(1) and H(2) receptors activities in the LC, especially by H(1) receptors. Moreover, the effects of the central HA on CSR might be related to a histaminergic descending pathway from the hypothalamus to LC.

[Clinical and experimental study of 7 cases of acute lymphoblastic leukemia with dic(7;9) (pll;pll)].

OBJECTIVE: To investigate the laboratory and clinical features of 7 cases of acute lymphoblastic leukemia (ALL) with dic(7;9) (pll;pll). METHODS: Cytogenetic examination of bone marrow cells was performed by direct method or short-term culture method. R banding technique was used for karyotype analysis. bcr/abl fusion gene was detected by interphase FISH using dual-color bcr/abl probe in 6 cases. FISH using chromosome 7-specific alpha-satellite DNA probe and chromosome 9-specific alpha-satellite DNA probe and chromosome painting using whole chromosome 7 and 9 paints probes were performed respectively. RESULTS: Seven (0.88%) of 800 ALL patients were found to have dic(7;9) abnormality. Among them, dic(7;9) was the sole abnormality in 2 cases, t(9;22), other additional aberrations besides dic(7;9) in 4 cases and dic (7;9) with other abnormalities but no t(9;22) in one case. Hyperleukocytosis (> 100 x 10(9)/L) was found in 4 cases with dic(7;9) and t(9;22), and patients without t(9;22) had WBC < 100 x 10(9)/L. Enlargement of liver, spleen and/or lymph nodes were found in 6 cases. Immunophenotyping showed that 5/6 cases of dic (7;9) ALL were of B lineage. Dual-color FISH detected bcr/abl rearrangement in 3/6 cases and confirmed that the centromere of the derivative chromosome was originated from both chromosomes 7 and 9. A reciprocal translocation between chromosomes 7 and 9 was proved by chromosome painting. CONCLUSION: dic(7;9) was a rare, but recurrent chromosome abnormality in ALL and had some clinical and laboratory features.