ObjectiveTo investigate the effects of hypoxia-treated mesenchymal stem cell （MSCs） exosomes （Exo） and their loading with curcumin on microglial inflammatory responses， and to explore the enhancing effect of hypoxia treatment on the function of MSCs Exo. MethodsThe supernatants of human umbilical cord （hUC）-MSCs cultured under normal and hypoxic conditions were collected， and Exo were isolated using ultracentrifugation. After identification by transmission electron microscopy and Western blot， curcumin was loaded using the co-incubation method. The lipopolysaccharide （LPS）-induced microglial inflammation model was treated with dimethyl sulfoxide （DMSO）， curcumin， normoxia Exo， hypoxia Exo， normoxic Exo loaded with curcumin， and hypoxic Exo loaded with curcumin， respectively. The expression of the M1-type marker inducible nitric oxide synthase （iNOS） in BV2 cells was detected by immunofluorescence （IF）. Western blot and enzyme-linked immunosorbent assay （ELISA） were used to measure the expression and secretion levels of tumor necrosis factor-α （TNF-α）， interleukin-1β （IL-1β）， and IL-6 in the cells and their culture supernatants. ResultsNormoxia Exo， hypoxia Exo， normoxic Exo loaded with curcumin， and hypoxic Exo loaded with curcumin exhibited a "saucer-like" shape with a diameter ranging from 30~150 nm， and the expression of exosomal markers CD9， CD81， and TSG101 were positive. After treating the BV2 cell inflammation model， IF results showed that， compared with the normoxia Exo group， treatment with hypoxic Exo significantly reduced the expression of iNOS. Moreover， when compared with the curcumin group and the normoxic Exo loaded with curcumin group， the expression level of iNOS significantly decreased after treatment with hypoxic Exo loaded with curcumin. The results of Western blot and ELISA indicated that， in comparison with the normoxia Exo group， treatment with hypoxic Exo significantly reduced the expression and secretion of the inflammatory cytokines TNF-α， IL-1β， and IL-6. Additionally， when compared with the curcumin group and the normoxic Exo loaded with curcumin group， both the expression and secretion of TNF-α， IL-1β， and IL-6 significantly decreased after treatment with hypoxic Exo loaded with curcumin. ConclusionHypoxia preconditioning can enhance the ability of hUC-MSCs-Exo in the inhibition of microglial polarization and inflammatory factors’ secretion. Additionally， using Hypoxia-MSCs-Exo as a drug-delivery carrier of curcumin can improve its solubility and stability， facilitating its absorption by cells and exerting the therapeutic effect of combination therapy.

Objective:To investigate the relationship between the protein expression of C-MYC, bcl-2 and bcl-6 and the clinicopathological characteristics in patients with de novo CD5-positive diffuse large B cell lymphoma (CD5 +DLBCL). Methods:Fifty seven cases of de novo CD5 +DLBCL were collected at Ruijin Hospital Affiliated to Shanghai Jiaotong University School of Medicine from February 2013 to September 2018. The hematoxylin-eosin stained slides were reviewed, and immunohistochemical (IHC) staining and FISH were used to analyze the relationship between C-MYC, bcl-2, bcl-6 expression and the clinicopathologic characteristics of patients. Results:Among these 57 cases, 27 were male and 30 were female. The age of onset was 35-99 years old. The IHC expression rates of C-MYC, bcl-2 and bcl-6 were 50.9% (29/57), 84.2% (48/57), and 75.4% (43/57) respectively; and co-expression rate of C-MYC and bcl-2 proteins was 40.4 (23/57). There was no significant correlation between protein expression and patients′ genders, clinical stage, the level of serum LDH,β2 microglobulin, IPI,B symptoms, bone marrow involvement and central nervous system recurrence ( P>0.05). Univariate analysis showed that the median OS of C-MYC negative patients was significantly longer than C-MYC positive patients ( P<0.05); and the median OS of patients without double expression was significantly longer than that of patients with positive expression ( P<0.05), and bcl-6 positive patients had longer median OS than bcl-6 negative patients ( P<0.05). There was no significant correlation between prognosis and bcl-2 protein expression ( P>0.05) . Cox multivariate analysis showed C-MYC protein expression was an independent predictor of OS in de novo CD5 +DLBCL ( P<0.05). Conclusions:Bcl-2 protein expression has no effect on the prognosis in de novo CD5 +DLBCL whereas bcl-6 expression is correlated with good prognosis. C-MYC protein expression could be used as an independent and effective index to predict the prognosis of patients with de novo CD5 +DLBCL.However, the relationship between protein expression and gene rearrangement of C-MYC, bcl-2 and bcl-6 needs to be further explored.

OBJECTIVE: To investigate the rapid and accurate method for the detection of dengue virus (DENV) by using nicking enzyme assisted strand-displacement amplification (SDA) combined with gold nanoparticles-based lateral flow strip. METHODS: Total RNA of the virus was extracted by using magnetic beads method and transcribed to cDNA for SDA detection system. Nicking enzyme-assisted method was used for detecting DENV, and agarose gel electrophoresis was used for analyzing the sensitivity of SDA amplification products. A gold nanoparticles-based lateral flow strip was developed based on the principle of nucleic acid base complementary pairing to design the test line and control line. The gold particles were prepared by using sodium citrate reduction method for gold nanoparticles-based lateral flow strip construction. RESULTS: The sensitivity of the SDA method was 10 fmol/L, and the sensitivity of gold nanoparticles-based lateral flow strip based on SDA method was also 10 fmol/L. In a linear range from 10 fmol/L to 10 fmol/L, the corresponding linear correlation coefficient () of DENV was 0.98. The specificity of nanoparticles-based lateral flow strip based on SDA for DENV detection was high, which was no crossing with other control groups. CONCLUSIONS A gold nanoparticles-based lateral flow strip based on SDA method for DENV detection has been established, which is convenient, fast, and the result is visible to naked eyes.
Dengue ; diagnosis ; Dengue Virus ; isolation & purification ; Gold ; Humans ; Metal Nanoparticles ; Reproducibility of Results ; Sensitivity and Specificity