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Development of multiple drug resistance has been attributed to the overexpression of the ATP-binding cassette B1 ( ABCB1) gene. In this study, the major purpose was to assess the expression and methylation levels of ABCB1 in human lung adenocarcinoma and to reveal the relationship between these processes and acquisition of cisplatin ( DDP) resistance in the human cancer cell line A549. Methylation and expression levels of the ABCB1 gene ABCB1 in clinical human lung tissue were assessed using bisulphite sequencing, reverse transcription real-time PCR ( RT2- PCR) and Western blot methods. Cell viability, DDP resistance and apoptosis of A549 cells were evaluated using the Cell Counting Kit-8 and fluorescence-activated cell sorter analysis. Our results showed that the onset of resistance to the cisplatin analogue, DDP, was associated with hypermethylation of the ABCB1 gene. Expression of the ABCB1 gene was enhanced at both mRNA and protein levels. Treatment with 5-Aza-C contributed to the hypomethylation of the ABCB1 gene and decreased ABCB1 protein expression in A549 cells. In conclusion, this in vitro and human tissue study of lung adenocarcinoma cells demonstrated that hypermethylation of the ABCB1 gene correlated with increased gene expression and was associated with the acquisition of resistance to the cisplatin analogue, DDP in human lung adenocarcinoma cells. Taken together, our study highlighted the connection between increased ABCB1 methylation level and upregulated expression of the gene in lung cancer. Moreover, the abnormally high expression of ABCB1 in A549 cells contributed to the development of the DDP resistance. [ABSTRACT FROM AUTHOR]

Particle size has been demonstrated as a key parameter influencing the phagocytosis of drug-loaded PLGA microspheres (MS) by the target cells. However, the current preparative methods were either insufficient in controlling the homogeneity of the produced MS, or requires sophisticated and costly equipment. This study aimed to explore a simple and economical method for uniform PLGA MS preparation. Based on the heterogeneous emulsification of routine mechanical stirring, we designed an adjuvant strategy to enhance the homogeneity of MS. By using glass beads as adjutant, the dispersion produced during mechanical stirring was much more homogeneous in the solution. The particles produced were much smaller and the size distribution was much narrower as compared with those produced using the routine mechanical stirring method under the same condition. After enrichment by selective centrifugation, about 60% of the particles of similar size were obtained, providing further evidence for the efficiency of the novel method in controlling particle homogeneity. Further, the method was applied to prepare rifampicin-loaded PLGA MS of the optimized size for macrophage uptake. The functional evaluation showed that the prepared PLGA MS could efficiently deliver an antitubercular drug into macrophages and maintain a higher intracellular concentration by controlled release, suggesting the potential application of the method in PLGA MS-based drug delivery. Collectively, the study provided a simple and economical method for preparing uniform-sized PLGA MS with potential of widespread applications. [ABSTRACT FROM AUTHOR]

The common features shared by primary plasma cell leukemia (pPCL) and multiple myeloma (MM) with circulating plasma cells (CPCs) are peripheral blood invasion and expansion of plasma cells independent of the protective bone marrow (BM) microenvironment niche. However, few studies have addressed the relationship between pPCL and MM with CPCs. Here, we quantitated the number CPCs by conventional morphology in 767 patients with newly diagnosed MM; their clinic features were compared with those of 33 pPCL cases. When the presence of CPCs was defined as more than 2 % plasma cells per 100 nucleated cells on Wright-Giemsa stained peripheral blood smears, the incidence of MM with CPCs was 14.1 % in newly diagnosed MM. Patients with CPCs shared many clinical features with pPCL, especially clinical parameters related to tumor burden. However, no commonalities were found in immunophenotyping and cytogenetics. The prognosis of pPCL was poor, with a median progression free survival (PFS) of 12 months and an overall survival (OS) of 15 months. MM patients with CPCs had a clearly inferior PFS and OS as compared with the control cohort. Most interestingly, although the CPCs were not high enough to meet the diagnostic criteria for pPCL, the survival of MM patients with CPCs was comparable with that of pPCL, with a median PFS of 17 months and an OS of 25 months. [ABSTRACT FROM AUTHOR]

To explore the best treatment for early natural killer/T (NK/T)-cell lymphoma, we compared the efficacy and safety of DDGP (pegaspargase, gemcitabine, cisplatin and dexamethasone) followed by radiotherapy (RT) and VIPD (etoposide, ifosfamide, cisplatin, and dexamethasone) followed by radiotherapy for newly diagnosed patients. 40 newly diagnosed patients with stage I-II from January 2011 to November 2016 were treated with DDGP followed by radiotherapy or VIPD followed by radiotherapy. They were assessed in this study. The complete response rate (CRR) and overall response rate (ORR) of the DDGP followed by radiotherapy group were higher than those of the VIPD followed by radiotherapy group (CRR: 85 % vs 50 %, P = 0.018; ORR: 95 % vs 65 %, P = 0.048). The 5-year progression-free survival (PFS) rate was better in the DDGP followed by radiotherapy group (83.3 % vs 44.4 %, χ2 = 7.809, P = 0.005). There was no significant difference in the 5-year overall survival (OS) rate between the two groups (83.0 % vs 72.1 %, χ2 = 0.231, P = 0.631). Treatment method (P = 0.011) and IPI score (P = 0.027) were independent risk factors for PFS. The DDGP followed by radiotherapy group was more prone to grade I-II clotting dysfunction (P = 0.004). In patients newly diagnosed with early NK/T-cell lymphoma, those treated with DDGP followed by radiotherapy had a higher CRR and ORR and longer PFS than those treated with VIPD followed by radiotherapy, and adverse reactions were tolerable. • Radiotherapy combined with chemotherapy has good results in early ENKTL. • DDGP followed by RT had a higher CRR and ORR and longer PFS in early ENKTL. • Adverse reactions in DDGP followed by RT group were tolerable. • Patients were more likely to progress in VIPD followed by RT group. [ABSTRACT FROM AUTHOR]

Emetic Bacillus cereus (B. cereus) is a foodborne microorganism associated with vomiting disease. Herein, we have established a blocker-tailed polymerase chain reaction (bt-PCR) coupled with rolling circle amplification (RCA) assay for the sensitive and specific detection of emetic B. cereus. In this research, the designed forward primer for bt-PCR was modified into two parts, namely, the C3 spacer blocker, and the linker DNA binding sequence, which was complementary with the linker DNA. The bt-PCR products could bind to the linker DNA and initiate the RCA assay, generating numerous repetitive G-quadruplex structures. The specific fluorescence dye of thioflavin T (ThT) could bind to the G-quadruplex structures, producing enhanced fluorescent signals for detection. Under optimized conditions, the proposed assay could improve the sensitivity of the conventional PCR detection, and the limit of detection (LOD) was 2.6 × 100 CFU/mL in pure culture, and 2.8 × 100 CFU/mL in spiked milk samples with good specificity. The proposed assay showed potential application for the detection of emetic B. cereus in real world. • The tailed-PCR products could be used as ssDNA for further amplification. • The assay could detect 10° CFU/mL emetic B. cereus in pure culture and spiked milk. • Sensitivity of the double signal amplification assay was 100-fold higher than PCR. • The assay could be applied to other pathogens by altering the target sequences. [ABSTRACT FROM AUTHOR]

Abstract: A double-antigen sandwich ELISA was developed a detection of HCV antibodies by a recombinant multi-epitope HCV antigen and a biotin–streptavidin amplification system. Three plasma specimens from 1708 individuals who were suspected previously to be HCV-positive using an HCV antibody diagnostic kit (Chuangxin, Xiamen, China) displayed negative results when using the ELISA. These results were validated by a recombinant immunoblotting assay (two were negative, and one was indeterminate). Among 889 blood specimens donated for clinical evaluation, 246 were positive and 630 were negative using the ELISA. The sensitivity and specificity of the ELISA were 98.7% and 100%, respectively. In 43 donors and 14 patients with chronic hepatitis C, the detectable rates for HCV IgM by both ELISA and the HCV anti-IgM detection reagents (Huimin, Shenyang, China) were 100%, and the detectable rate for HCV IgG using an indirect HCV-antibody detection kit (GWK, Beijing, China) was 98.3%. Thus, the double-antigen sandwich ELISA exhibits strong specificity and sensitivity and has been approved by the China State Food and Drug Administration (SFDA). The performance of the double-antigen sandwich ELISA was similar to the Ortho ELISA 3.0. It did not give false-negative results otherwise IgM was undetectable using an indirect HCV-antibody detection kit. This ELISA provides another method for the detection of HCV antibodies. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus (S. aureus) is a common pathogen that can cause severe foodborne diseases. Therefore, the detection of S. aureus in food has been the focus of attention. In this study, a strategy for the detection of S. aureus using magnetic separation technology combined with colorimetry was proposed. Phenylboronic acid, as a compound that had been widely used in the identification of sugars and sugar-based molecules, can selectively enrich compounds with cis -diol groups through a reversible esterification reaction. Hence, 3-aminophenylboronic acid (APBA) could be used as a recognition molecule to capture bacteria, because there were a large amount of peptidoglycan and lipopolysaccharide on the surface of Gram-positive bacteria and Gram-negative bacteria. At the same time, there are few studies on the use of APBA as magnetic separation recognition molecule to enrich pathogenic bacteria. Therefore, we prepared APBA-functionalized magnetic beads (APBA-MBs) for pre-enrichment of S. aureus and an APBA-MBs based untargeted magnetic separation was constructed to replace the traditional targeted magnetic separation. In order to realize the output signal and guarantee the specificity for detecting S. aureus , we used HRP-pig IgG because the Fc fragment of IgG could bind the protein A on the cell wall of S. aureus. Finally, the tetramethylbenzidine (TMB) color development solution was occurred the chromogenic reaction under the action of the HRP enzyme. Under the optimal experimental conditions, the limit of detection (LOD) of the APBA-MBs combined with color reaction was 3.0 × 102 CFU/mL in pure culture, fruit juice, pool water and spinach. • Using APBA to replace expensive recognition molecules such as antibiotics. • The CE of S. aureus can reach 90%–100% in the range of 106 to 101 CFU/mL. • The strategy has good performance in different matrixes. • The strategy can realize the detection of S. aureus within 2 h. [ABSTRACT FROM AUTHOR]

Cancer is one of the main diseases threatening human health in the world. Doxorubicin (DOX) is a common anti-cancer drug that can be used for chemotherapy to extend a cancer patient's life. It is our common wish that treatment process of cancer is efficient and secure. Therefore, it is of great significance to develop sensitive, rapid and accurate techniques for anti-cancer drug doxorubicin (DOX) detection. Herein, in our work, a ratiometric electrochemical sensor for DOX detection was designed, which based on MB@MWCNTs/UiO-66-NH 2 composites. The porous materials UiO-66-NH 2 magically shoulder double function in our ratiometric electrochemical strategy, which can reduce the interior error caused by the various complex materials. Specifically, on the one hand, it can be used to catalyze DOX, which can provide a great current signal to be detected, on the other hand, its special property of absorbing molecules was utilized to load materials as internal reference. Consequently, we chose methylene blue (MB) as the substance that can generate an internal reference signal, because it is a specific and stable electroactive substance. Then, we added MWCNTs as a part of the material modified on the ratiometric electrochemical platform to enhance the signal of the target due to its feature of good electrical conductivity. Under the optimized conditions, the ratiometric electrochemical sensor displayed a wide linear detection with the range from 0.1 μM to 75 μM and the limit of detection (LOD) of 0.051 μM. The applicability of this method in the analysis of actual human saliva samples has been confirmed by the results of selectivity, stability, and reproducibility tests, which was prospective in clinical application. [Display omitted] • Multiple function MOF was designed for ratiometric electrochemical detection of DOX. • The UiO-66-NH 2 /MWCNTs can bring catalytic reaction towards target to amplify the detection signal. • The multiple function MOF platform can be extended for analysis of other target. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7 (E. coli O157:H7) is a common foodborne morbigenous microorganism, which can spread through fecal-oral transmission. Humans can be infected by ingesting foods and water contaminated with E. coli O157:H7, which can cause various symptoms. In present study, we have successfully developed a quick and hypersensitive fluorescent probe-based Recombinase-aided amplification (RAA) method and applied in E. coli O157:H7 detection at 39 °C in 20 min. The sensitivity of the assay in pure E. coli O157:H7 suspension was 5.6 × 100 CFU/mL. The fluorescent probe-based RAA assay was further applied in three samples, and the limit of detection (LOD) in skimmed milk, lettuces and lake water was 5.4 × 101 CFU/mL, 7.9 × 101 CFU/mL and 5.2 × 101 CFU/mL, separately. This method showed a high sensitivity and short detection time, which has the feasible application in on-site test in real samples. • RAA combined fluorescent probe achieved one step for amplification and read-out. • RAA is rapid isothermal amplification and performed at 39 °C within 20 min. • E. coli O157:H7 was detected by the proposed assay in multiple real samples. [ABSTRACT FROM AUTHOR]

Staphylococcus aureus is a common foodborne pathogenic microorganism. A modified propidium monoazide (PMAxx) dye combined with recombinase aided amplification (RAA) was proposed for the rapid and real-time detection of viable S. aureus. PMAxx, a kind of nucleic acid dye is used to distinguish viable bacteria from dead bacteria. Additionally, RAA technique has the advantage of a short detection time (20 min) and uniform temperature (39 °C), which is of great significance for the efficient detection of S. aureus. The S. aureus nuc gene was used as primer and probe in a microplate assay. The effect of PMAxx treatment exhibited permeation of the dead cell membranes that was observed under confocal laser scanning microscope (CLSM). After the enrichment of viable target bacteria ranging from 5.4 × 101 to 5.4 × 103 CFU/mL, the LOD for viable S. aureus was 102 CFU/mL under 3 h enrichment and 101 CFU/mL under 6 h enrichment in artificially contaminated milk, respectively. In the presence of nontarget bacteria at 106 CFU/mL, the system could detect 107 CFU/mL S. aureus in milk sample. The proposed PMAxx-RAA assay exhibited potential for the accurate and rapid viable S. aureus detection in milk. • Real-time fluorescence detection reactions of Staphylococcus aureus were reported. • PMAxx was selected to more accurately eliminate the interference from dead cells. • Verify the effect of PMAxx through confocal laser scanning microscope (CLSM). • The assay could detect 101 CFU/mL viable cells in milk sample after 6 h enrichment. [ABSTRACT FROM AUTHOR]

Background: This study was to examine the link between astrocyte elevated gene-1 (AEG-1) and hypoxia induced-chemoresistance in T-cell non-Hodgkin's lymphoma (T-NHL), as well as the underlying molecular mechanisms. Methods: Expression of AEG-1, LC3-II, and Beclin-1 were initially examined in human T-NHL tissues (n = 30) and normal lymph node tissues (n = 16) using western blot, real-time PCR and immunohistochemistry. Western blot was also performed to analyze the expression of AEG-1, LC3-II, and Beclin-1 in T-NHL cells (Hut-78 and Jurkat cells) under normoxia and hypoxia. Additionally, the proliferation and apoptosis of Hut-78 cells exposed to different concentration of Adriamycin (ADM) in normoxia and hypoxia were evaluated by MTT and Annexin-V FITC/PI staining assay. Finally, the effects of AEG-1 on Hut-78 cells exposed to ADM in hypoxia were assessed by MTT and Annexin-V FITC/PI staining assay, and 3-MA (autophagy inhibitor) was further used to determine the underlying mechanism. Results: AEG-1, LC3-II and Beclin-1 expression were significantly increased in T-NHL tissues compared with normal tissues. Incubation of Hut-78 and Jurkat cells in hypoxia obviously increased AEG-1, LC3-II and Beclin-1 expression. Hypoxia induced proliferation and reduced apoptosis of Hut-78 cells exposed to ADM. AEG-1 overexpression further increased proliferation and decreased apoptosis of Hut-78 cells exposed to ADM in hypoxia. Moreover, overexpression of AEG-1 significantly inversed 3-MA induced-changes in cell proliferation and apoptosis of Hut-78 cells exposed to ADM in hypoxia. Conclusions: This study suggested that AEG-1 is associated with hypoxia-induced T-NHL chemoresistance via regulating autophagy, uncovering a novel target against hypoxia-induced T-NHL chemoresistance. [ABSTRACT FROM AUTHOR]