[Cell Cycle Arrest and Apoptosis Induced by Atovaquone in Non-Hodgkin's Lymphoma Raji Cells].

OBJECTIVE: To investigate the effect of atovaquone on the cell cycle and apoptosis of non-Hodgkin's lymphoma Raji cells, and clarify the related mechanisms. METHODS: MTT assay and trypan blue dye exclusion method were used to evaluate the effect of atovaquone on the proliferation of Raji cells. After the cells were stained by PI staining, the cell cycle distribution was detected by flow cytometry. Cell apoptosis was analyzed by Annexin V/PI double binding assay. The intracellular alterations of reactive oxygen species were detected by 2', 7'-dichlorofluorescein diacetate (DCFH-DA). The protein expression of cell cycle and apoptosis related molecules were detected by Western blot. RESULTS: Various concentrations of atovaquone (5-40 µmol/L) inhibited the growth of Raji cells in a concentration-dependent manner (r=0.951). The proliferation of Raji cells was significantly inhibited after treated by atovaquone (20 and 30 µmol/L) for 24, 48 and 72 h, which showed statistically different with that in the control group (P<0.01, P<0.001, P<0.001). G1 phase arrest (P<0.01, P<0.001) and apoptosis (P<0.01) of Raji cells was induced by atovaquone (20 and 30 µmol/L) significantly for 24 h and 48 h, respectively. The expression of p-JAK2 and p-STAT3(Y705) protein were down-regulated significantly induced by atovaquone (P<0.001, P<0.05). Furthermore, atovaquone treatment could induce the decreasing of antiapoptotic protein Mcl-1, Bcl-2, and Bcl-xl expression level (P<0.05) and increasing of cleaved caspase-3 protein expression level. In addition, atovaquone could also induce the down-regulation of c-Myc (P<0.001, P<0.01) and cell cycle related molecules Cyclin D1, CDK4, and CDK6 (P<0.01, P<0.05) protein expression. CONCLUSION: Atovaquone effectively inhibits cell proliferation and induces cell cycle arrest and apoptosis by suppression of STAT3 signaling pathway in Raji cells. It can be a potential therapeutic agent against non-Hodgkin's lymphoma.

Functionalized AuMBA @Ag Nanoparticles as an Optical and SERS Dual Probe in a Lateral Flow Strip for the Quantitative Detection of Escherichia coli O157:H7.

A method combining surface-enhanced Raman scattering (SERS) with a lateral flow strip (LFS) was developed for the quantitative and sensitive analysis of Escherichia coli O157:H7. AuMBA @Ag nanoparticles were prepared as SERS probes, and 4-methylthiobenzoic acid (MBA) as a Raman reporter was inserted into the interior gap of the Au@Ag core-shell nanoparticles, which replaced the Au nanoparticles that serve as SERS nanotags in traditional LFS. Using this developed SERS-LFS, the presence of the target bacteria could be tested through the appearance of a red band on the test line. Furthermore, quantitative analysis of E. coli O157:H7 was achieved by measuring the specific Raman intensity of MBA on the test line. The sensitivity of this SERS-LFS biosensor is 5 × 104 CFU/mL of E. coli O157:H7, which is 10-fold higher than that of a naked eye-based colorimetric LFS. This quantitative detection of E. coli O157:H7 ( Y = 1993.86 X - 6812.17, R2 = 0.9947) was obtained with a wide linear range (5 × 104 to 5 × 108 ) due to the signal enhancement of the SERS nanotags. In addition, the SERS-LFS could differentiate E. coli O157:H7 from closely related bacterial species or nontarget contaminants, suggesting high specificity of this assay. The applicability of SERS-LFS to the analysis of E. coli O157:H7 in milk, chicken breast, and beef was also validated, indicating that the sensitivity was not disturbed by the food matrix. In summary, the SERS-LFS developed in this study could be a powerful tool for the quantitative and sensitive screening of E. coli O157:H7 in a food matrix. PRACTICAL APPLICATION: This study demonstrates that a surface-enhanced Raman scattering (SERS)-based lateral flow strip (LFS) could be used as a rapid and sensitive method for Escherichia coli O157:H7 detection. Furthermore, this SERS-based LFS could achieve quantitative detection of the target, eliminating the defect of the traditional colloidal gold LFS, which is not quantifiable.

Long-term continuous exposure to static magnetic field reduces popolysaccharide-induced cytotoxicity of fibroblasts.

PURPOSES: Lipopolysaccharide (LPS) is one of the major substances initiating the immune host response in microbial infections that results in cytotoxicity. In terms of treatment of the immune response, research has been conducted on physical environments that can reduce LPS-induced damage. In this experiment, a long-term continuous static magnetic field (SMF) was used as a physical resource to reduce LPS-induced immune host response. MATERIALS AND METHODS: Cultured fibroblasts were challenged with LPS to initiate an inflammatory reaction. Cell viability and various proinflammatory cytokine levels were detected and compared between SMF and sham-exposed groups. RESULTS: Our in vitro study revealed that, with LPS challenge, fibroblasts continuously exposed to a 0.4-T SMF for 12 h demonstrated higher cell viability compared to unexposed analogs. From cytokine test, the levels of LPS-induced interleukin-1beta (IL-1beta) in the SMF-exposed groups were significantly lower relative to their unexposed counterparts (p < 0.05). By contrast, SMF exposure tended to increase the level of LPS-induced IL-1 receptor antagonist (IL-1Ra) and IL-6. CONCLUSIONS: Our results suggest that SMF stimulation inhibits LPS-induced cytotoxicity through reduction of proinflammatory cytokines and increase in anti-inflammatory cytokines of NIH-3T3 cells.

The treatment effects of flaxseed-derived secoisolariciresinol diglycoside and its metabolite enterolactone on benign prostatic hyperplasia involve the G protein-coupled estrogen receptor 1.

Secoisolariciresinol diglucoside (SDG), a lignan extracted from flaxseed, has been shown to suppress benign prostatic hyperplasia (BPH). However, little is known about the mechanistic basis for its anti-BPH activity. The present study showed that enterolactone (ENL), the mammalian metabolite of SDG, shared the similar binding site of G1 on a new type of membranous estrogen receptor, G-protein-coupled estrogen eceptor 1 (GPER), by docking simulations method. ENL and G1 (the specific agonist of GPER) inhibited the proliferation of human prostate stromal cell line WPMY-1 as shown by MTT assay and arrested cell cycle at the G0/G1 phase, which was displayed by propidium iodide staining following flow cytometer examination. Silencing GPER by short interfering RNA attenuated the inhibitory effect of ENL on WPMY-1 cells. The therapeutic potential of SDG in the treatment of BPH was confirmed in a testosterone propionate-induced BPH rat model. SDG significantly reduced the enlargement of the rat prostate and the number of papillary projections of prostatic alveolus and thickness of the pseudostratified epithelial and stromal cells when comparing with the model group. Mechanistic studies showed that SDG and ENL increased the expression of GPER both in vitro and in vivo. Furthermore, ENL-induced cell cycle arrest may be mediated by the activation of GPER/ERK pathway and subsequent upregulation of p53 and p21 and downregulation of cyclin D1. This work, in tandem with previous studies, will enhance our knowledge regarding the mechanism(s) of dietary phytochemicals on BPH prevention and ultimately expand the scope of adopting alternative approaches in BPH treatment.

Effect of Flaxseed Intervention on Inflammatory Marker C-Reactive Protein: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

Functional food-flaxseed and its derivatives (flaxseed oil or lignans) are beneficial for human health, possibly because of their anti-inflammatory effects. C-reactive protein (CRP), a sensitive marker of inflammation was chosen to evaluate the anti-inflammatory effects of flaxseed. We searched randomized controlled trials from PubMed and the Cochrane Library in October 2015 and conducted a meta-analysis to evaluate the effectiveness of flaxseed and its derivatives on CRP. The mean differences (net change) in CRP (mg/L) concentrations were pooled with a random- or a fixed-effects model depending on the results of heterogeneity tests. Overall, flaxseed interventions had no effects on reduction of CRP (p = 0.428). The null effects were consistent in the subgroup analysis with multiple studies and population characteristics. Significant heterogeneity was observed in most of the analyses. Meta-regression identified baseline body mass index (BMI) as a significant source of heterogeneity (P-interaction = 0.032), with a significant reduction in CRP of 0.83 mg/L (95% confidence interval -1.34 to -0.31; p = 0.002) among subjects with a BMI of ≥30 kg/m². In conclusion, our meta-analysis did not find sufficient evidence that flaxseed and its derivatives have a beneficial effect on reducing circulating CRP. However, they may significantly reduce CRP in obese populations.

A coumarin-based two-photon probe for hydrogen peroxide.

A new fluorescence probe was developed for hydrogen peroxide (H2O2) detection based on donor-excited photo induced electron transfer (D-PET) mechanism, together with the benzil as a quenching and recognizing moiety. The benzil could convert to benzoic anhydride via a Baeyer-Villiger type reaction in the presence of H2O2, followed by hydrolysis of benzoicanhydride to give benzoic acid, and the fluorophore released. The probe was synthesized by a 6-step procedure starting from 4-(diethylamino)salicylaldehyde. A density functional theory (DFT) calculation was performed to demonstrate that the benzil was a fluorescence quencher. The probe was evaluated in both one-photon and two-photon mode, and it exhibited high selectivity toward H2O2 over other reactive oxygen species and high sensitivity with a detection limit of 0.09 µM. Furthermore, the probe was successfully applied to cell imaging of intracellular H2O2 levels with one-photon microscopy and two-photon microscopy. The superior properties of the probe made it of great potential use in more chemical and biological researches.

An 1,3,4-oxadiazole-based OFF-ON fluorescent chemosensor for Zn2+ in aqueous solution and imaging application in living cells.

A new 1,3,4-oxadiazole-based fluorescence chemosensor 1, N-(2-ethoxy-2-oxoethyl)-N-(5-(2-hydroxy-3,5-di-tert-butylphenyl)-[1,3,4]oxadiazol-2-yl)glycine ethyl ester, has been designed and synthesized. Its fluorescence properties and selectivity for various metal ions were investigated in detail. A prominent fluorescence enhancement only for Zn(2+) was found in aqueous acetonitrile solution and the response mechanism of 1 was analyzed by time-resolved fluorescence decay and DFT calculations. Furthermore, the fluorescence imaging of Zn(2+) in living cells was successfully applied.

Synovial chondromatosis of the hip: management with arthroscope-assisted synovectomy and removal of loose bodies: report of two cases.

Primary synovial chondromatosis is an uncommon disorder, and involvement of the hip joint is rare. The clinical symptoms are usually non-specific, and a clinical diagnosis of synovial chondromatosis of the hip may be difficult and delayed, especially before the ossifying nodules become evident. Loose bodies in the joint can cause secondary degenerative osteoarthritis of the hip. Currently, the recommended management is surgical removal of the loose bodies and a synovectomy without dislocation of the hip joint. Herein we report on 2 cases of synovial chondromatosis of the hip, which were managed with an arthroscope-assisted synovectomy and removal of the loose bodies. We believe this is an easy and safe method for management of this disorder.