Establishment of a recombined mannose-binding lectin protein-magnetic beads-enriched binding recombinant enzyme-assisted polymerase chain reaction assay for Candida in blood samples / 中华流行病学杂志

Objective: To establish a nested recombinant enzyme-assisted polymerase chain reaction (RAP) technique combined with recombined mannose-binding lectin protein (M1 protein)-magnetic beads enrichment for the detection of Candida albicans (C. albicans) and Candida tropicalis (C. tropicalis) in blood samples for the early diagnosis of candidemia albicans and candidiemia tropicalis. Methods: The primer probes for highly conserved regions of the internal transcribed spacerregions of C. albicans and C. tropicalis were deigned to establish RAP assays for the detections of C. albicans and C. tropicalis; The sensitivity and reproducibility of nucleic acid tests with gradient dilutions of standard strains and specificity of nucleic acid tests with common clinical pathogens causing bloodstream infection were condcuted. M1 protein-magnetic bead enriched plasma C. albicans and C. tropicalis were used for RAP and PCR in with simulated samples and the results were compared. Results: The sensitivity of the established dual RAP assay was 2.4-2.8 copies/reaction, with higher reproducibility and specificity. M1 protein-magnetic bead enrichment of pathogen combined with the dual RAP assay could complete the detections of C. albicans and C. tropicalis in plasma within 4 hours. Fie the pathogen samples at concentration <10 CFU/ml, the number of the samples tested by RAP was higher than that tested by PCR after enrichment. Conclusion: In this study, a dual RAP assay for the detections of C. albicans and C. tropicalis in blood sample was developed, which has the advantages of accuracy, rapidity, and less contaminants and has great potential for rapid detection of Candidemia.

Knockdown of long non-coding RNA MIR4697 host gene inhibits adipogenic differentiation in bone marrow mesenchymal stem cells / 北京大学学报(医学版)

OBJECTIVE@#To preliminarily investigate the role of long non-coding RNA (lncRNA) MIR4697 host gene (MIR4697HG) in regulating the adipogenic differentiation of bone marrow mesenchymal stem cells (BMSCs).@*METHODS@#For adipogenic differentiation, BMSCs were induced in adipogenic media for 10 days. The mRNA expression levels of lncRNA MIR4697HG and adipogenic marker genes including peroxisome proliferator-activated receptor γ (PPARγ), CCAAT/enhanced binding protein α (CEBP/α) and adiponectin (ADIPQ) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) at different time points (0, 1, 2, 3, 5, 7, 10 days). The MIR4697HG stable knockdown-BMSC cell line was generated by infection of MIR4697HG shRNA-containing lentiviruses. To avoid off-target effect, two target sequences (shMIR4697HG-1, shMIR4697HG-2) were designed. And then cells were induced to differentiate in adipogenic medium. Oil red O staining, Western blot and qRT-PCR were used to detect the effect of MIR4697HG knockdown on adipogenic differentiation of BMSCs.@*RESULTS@#The mRNA expression level of MIR4697HG was significantly increased during adipogenic differentiation (P < 0.01), and adipogenic differentiation of BMSCs was evidenced by upregulated mRNA levels of specific adipogenesis-related genes including PPARγ, CEBP/α and ADIPQ. Observed by fluorescence microscopy, more than 90% transfected target cells expressed green fluorescent protein successfully after shMIR4697HG-1 group, shMIR4697HG-2 group and shNC group transfection for 72 h. And the transfection efficiency of MIR4697HG examined by qRT-PCR was above 60%. Then the BMSCs were treated with adipogenic media for 7 days and showed that the mRNA expression levels of adipogenesis-related genes including PPARγ, CEBP/α and ADIPQ were significantly decreased in the MIR4697HG knockdown group (P < 0.01), while the expression levels of PPARγ and CEBP/α proteins were decreased remarkably as well (P < 0.01). Consistently, MIR4697HG knockdown BMSCs formed less lipid droplets compared with the control BMSCs, which further demonstrated that MIR4697HG knockdown inhibited adipogenic differentiation of BMSCs.@*CONCLUSION@#lncRNA MIR4697HG played a crucial role in regulating the adipogenic differentiation of BMSCs, and MIR4697HG knockdown significantly inhibited the adipogenic differentiation of BMSCs. These data may suggest that lncRNA MIR4697HG could serve as a therapeutic potential target for the aberrant adipogenic differentiation-associated disorders including osteoporosis.

Effect of Gamma knife treatment on level of prolactin in patients with pituitary prolactinomas / 中华神经医学杂志

Objective To analyze the effects of-γ-knife treatment with different dosages on level of prolactin (PRL) in patients with different sizes of functional pituitary prolactinomas, and determine an index to guide hormone replacement therapy and the prognosis of -γ-knife treatment in patients with functional pituitary prolactinomas through comparing the changes of tumor sizes and the levels of PRL before and after -γ-knife treatment. Methods A retrospective analysis of the clinical data of 248 patients with functional pituitary prolactinomas was performed; gamma knife treatment was performed on these patients from September 2004 to March 2008. We divided the patients into 3 groups: group Ⅰ (50 Gy≤central dose<60 Gy, 20 Gy＜marginal dose<30 Gy), group Ⅱ (40 Gy≤ central dose＜50 Gy, 15 Gy＜marginal dose<25 Gy) and group Ⅲ (30 Gy ≤ central dose<40 Gy, 12 Gy＜marginal dose<20 Gy). The irradiation dose on optic nerves in the 3 groups was under 9 Gy. Radioimmunoassay was employed to detect the serum PRL level before and 1, 3 and 12 months after γ-knife treatment. The changes of the tumor sizes were observed and compared with cranial MRI 1 and 2 years after -γ-knife treatment.Results Significant differences on the PRL level were noted before -γ-knife treatment between each 2 groups (P<0.05); the PRL level in group Ⅲ was lower as compared with that in group Ⅰ and Ⅱ before γ-knife treatment; however, the PRL level in group Ⅲ was higher as compared with that in group 112 months after -γ-knife treatment; the PRL level in all the 3 groups after γ-knife treatment was significantly lower as compared with that before γ-knife treatment (P<0.05). MRI showed that the tumor had 80% partial response rate (198/248) in the 1st year, 82% complete response rate (203/248) in the 2nd year, increased volume in 19 patients (7.7%) and no change in 26 patients (10.4%). Conclusion Different treatment doses of Gamma knife on functional pituitary prolactinomas has great influences on postoperative recovery of endocrine; the higher doses of the center and edge (especially center), the higher normal rate of postoperative PRL level. Whether it will cause long-term hypopituitarism needs continue follow-up.