Role of autophagy in advanced atherosclerosis (Review).

Atherosclerosis (AS) remains the leading cause for global cardiovascular disease morbidity and mortality, and a major cause of cardiopathy, myocardial infarction and peripheral vascular diseases. Macrophages serve a critical role in atherosclerotic plaque stabilization and rupture, and the selective removal of macrophages may be beneficial in improving plaque stability. Autophagy is a process of self­feeding, during which cytoplasmic proteins or organelles are packaged into vesicles and fused with the lysosome to form an autophagosome. The newly formed autophagosome can degrade internalized proteins, and this process may be used to serve the metabolic and self­renewal requirements of the cell. Autophagy serves an important role in maintaining cell homeostasis and promoting cell survival, and therefore an imbalance in autophagy is closely associated with multiple diseases.

Mipu1 inhibits lipid accumulation through down-regulation of CD36 in RAW264.7 cells.

BACKGROUND/AIMS: Our recent data indicated that Mipu1 overexpression reduces lipid intake and CD36 expression of macrophages in the presence of oxLDL. However, the mechanism of Mipu1 inhibiting lipid accumulation in macrophages is not elucidated. METHODS: Real-time quantitative polymerase chain reaction (PCR) and western blot analysis were used to detect expression of Mipu1 and CD36. The promoter activity of CD36 was studied using luciferase assays. Chromatin immunoprecipitation (ChIP) was used to show the recruitment of Mipu1 onto the CD36 promoter. High-performance liquid chromatography and Dil-labeled lipoprotein were used to detect cholesterol accumulation. RESULTS: Here, we show that CD36 overexpression rescues oxLDL-induced cholesterol accumulation in RAW264.7-Mipu1 cells. Analysis of the mouse CD36 promoter revealed two potential Mipu1-response elements (MRE), one of which (from -237bp to -244bp, ACTTAC) was shown, using mutagenesis and deletion analysis, to be functional. Mipu1 was demonstrated to bind to CD36 promoter, and oxLDL treatment resulted in increases in their interaction as assessed by ChIP. CONCLUSIONS: It was demonstrated that Mipu1 inhibited the lipid accumulation of macrophages and it down-regulated CD36 expression in the presence of oxLDL.

[Evaluation of detection and analysis of chromosome 22q11.2 microdeletion by multiple ligation-dependent probe amplification assay].

OBJECTIVE: To evaluate multiplex ligation-dependent probe amplification (MLPA) assay detection in analysis of chromosome 22q11.2 microdeletion. METHODS: Between March 2008 and September 2009, thirty-two patients including 10 males and 16 females aged between years (3.6±3.1) were selected and evaluated by history, physical examination and medical records. Of these patients, sixteen patients who were previous diagnostic as 22q11.2 microdeletion were in positive control group, the other 16 healthy children were in negative control group. All the patients were detected by MLPA and fluorescence in situ hybridization (FISH) for the presence of a 22q11.2 microdeletion after informed consent. Diagnostic efficacy was assessed by sensitivity, specificity and Kappa analysis. RESULTS: We have applied the two assays of detection of chromosome 22q11.2 microdeletion in 32 patients. Sixteen patients in positive control group were found to have a 22q11.2 deletion and, with the deletion size of 3-Mb. However, as expected, chromosome 22q11.2 deletion was not found in negative control group. The MLPA results were in good agreement with that by FISH. Therefore, MLPA has high sensitivity and specificity. CONCLUSION: MLPA is a rapid, reliable, high-throughput and relatively economical alternative to FISH technology for the diagnosis of 22q11.2 microdeletion. It can provide reliable and helpful information for clinical diagnosis of 22q11.2 microdeletion syndrome.

[Conventional and molecular cytogenetic analyses of a derivative X chromosome in amniocentesis].

OBJECTIVE: To analyze the aberrant der(X) chromosome using conventional and molecular cytogenetic approaches in a fetus of second trimester and to discuss its clinical effect. METHODS: Conventional cytogenetic procedures (GTG and CBG banding) were performed on cultured amniotic fluid cells. Three-color fluorescence in situ hybridization (FISH) consisting of X chromosome enumeration probes(CEPX), CEPY and Tel Xp/Yp was further performed to study the aberrant der(X) chromosome. RESULTS: Der(X) was a rare X/Y translocation. The final karyotypes of the fetus was designated as: 46,X,der(X)t(X;Y)(p22.3;q11.2). ish der(X)t(X;Y)(p22.3;q11.2)(X/Ypter-, DXZ1+, DYZ1+)mat. CONCLUSION: The combination of FISH and conventional cytogenetic techniques is a powerful tool to determine derivative chromosome and to offer an accurate genetic counseling. Identification of Xp; Yq rearrangement can help estimate the risk of fetus abnormalities and give a more precise prognosis.

[Sperm chromosome analysis and preimplantation genetic diagnos is in an infertile male with mosaic trisomy 18].

OBJECTIVE: To analyze the numerical aberration rate of X, Y and chromosome 18 in sperms from an oligozoospermic male with mosaic trisomy 18 and to perform preimplantation genetic diagnosis (PGD) for the couple. METHODS: G-banding and fluorescence in situ hybridization (FISH) were performed on metaphase chromosome. Sperm was analyzed in three-color FISH with a probe mixture containing CEP18, CEPY and Tel Xq/Yq. A healthy man with normal semen parameters was used as control. RESULTS: Significant difference in the rates of disomy for chromosome 18 (0.63% vs. 0.16%) and the gonosomes (0.945% vs. 0.35%) and diploidy (0.87% vs. 0.31%) was found in the spermatozoa between the patient and the control. After four embryos were biopsied in one PGD cycle, two embryos with XY1818 and XX1818 were selected for implanting and clinical pregnancy was ongoing. CONCLUSION: Sperm-FISH allows further understanding of aneuploidy rate and accurate genetic counseling. FISHPGD was effective for patient with mosaic trisomy 18.

Novel real-time PCR assay for rapid prenatal diagnosis of Down syndrome: a prospective study of 563 amniocytes.

OBJECTIVE: To explore the possibilities of a novel real-time PCR assay for rapid prenatal diagnosis of Down syndrome in clinical settings. DESIGN AND METHODS: This duplex real-time PCR assay is based on relative quantification of DSCR4 gene on chromosome 21 by using RABIF gene on chromosome 1 as a reference. For each sample, the differences in threshold cycles between DSCR4 and RABIF genes (Delta Ct, DeltaCt) were detected, and a calibrated DeltaCt value (DeltaDeltaCt, DeltaCt (sample)-DeltaCt (internal control)) was analyzed. Overall, 563 amniotic fluid samples from patients were blindly tested for fetal chromosome analysis and their DeltaDeltaCt values were evaluated according to the karyotyping results. RESULTS: Chromosome analysis revealed that 12 fetuses had trisomy 21 and 551 others were normal in chromosome 21. The DeltaDeltaCt values of trisomy 21 fetuses were significantly lower than those of normal ones (p-value<0.001) and no overlapping was shown: lower than -0.49 for trisomy 21 and above -0.30 for a normal one. CONCLUSIONS: DeltaDeltaCt value could be used as a direct diagnostic index in real-time PCR assay; this novel assay is applicable for rapid prenatal diagnosis of Down syndrome in clinical settings.

[Application of differential display-PCR technique in fluconazole-resistance gene expression of Candida].

OBJECTIVE: To investigate the application of differential display-2PCR(DD-PCR) in research on gene expression of Candida. METHODS: Resistance to fluconazole was induced in a Candida albicans isolate 435 from vagina by culturing in YEPD broth with increasing fluconazole concentration in vitro, and the resistant isolate 435-2 (MIC=128 microg/ml ) was obtained after 80 days of incubation. Comparisons between 435 and 435-2 either in fluconazole-containing medium or in drug-free medium were performed with the modified DD-PCR including amplification with long primers, silver staining, reverse dot blot and non-radiographic labeling techniques. RESULTS: Three differential displayed bands were found which showed high homology to alcohol dehydrogenase 1 (ADH1), TOP2 and CDR1, respectively. The up-regulating expression of ADH1 and CDR1 associated with fluconazole resistance was further identified by RT-PCR. CONCLUSION: The up-regulating expression of ADH1 and CDR1 was associated with fluconazole resistance in Candida albicans, ADH1 might be a candidate of novel fluconazole resistant gene.

[Study on experimental induction of fluconazole resistance in Candida albicans].

To investigate the phenotype and genotype variation between the Fluconazole resistant C. albicans isolates and the corresponding susceptible ones, our research established a resistance-induction mode in vitro. Comparisons were done on drug resistance maintainability, metabolic profile and the doubling time in the logarithmic growth phase. Genotypes were determined by ERIC-PCR. The Fluconazole resistant isolates appeared in strain 435, A06, B07 and C01 from total 22 clinical Fluconazole susceptible isolates after being incubated for 45-80 days in YEPD broth with increasing Fluconazole concentration. The parent isolates had a same metabolic profile and a similar growth doubling time to their filial generation. The same ERIC-PCR profiles were also found between the susceptible parents and their resistant filial isolates. The resistant isolates maintained drug resistance for 24 days after growing on drug-free medium. It was supposed that candida albicans had a latent capacity to evolve resistance to azoles under a certain antifungal drug selective pressure, and the acquired resistance could maintain in drug-free media for a certain period. The resistant isolate with no adaptive cost may be prone to vogue among people. ERIC-PCR could be used in epidemiological study as a stable marker.