Performance evaluation of the MAGLUMI Hepatitis B virus surface antigen chemiluminescence immunoassay.

A highly sensitive and reliable Hepatitis B virus surface antigen (HBsAg) measurement is essential to universal screening, timely diagnosis, and management of Hepatitis B virus (HBV) infection. This study aimed to evaluate the performance of MAGLUMI HBsAg chemiluminescence immunoassay (CLIA). MAGLUMI HBsAg (CLIA) was compared against ARCHITECT HBsAg. 411 HBsAg positive samples, including different stages of infection, genotypes, subtypes, mutants, and 30 seroconversion panels were tested to evaluate diagnostic sensitivity. Diagnostic specificity was evaluated by testing 205 hospitalized samples and 5101 blood donor samples. Precision, limit of blank (LoB), limit of detection (LoD), and linearity were also verified. The diagnostic sensitivity of the MAGLUMI HBsAg (CLIA) was 100% with better seroconversion sensitivity than ARCHITECT HBsAg. The MAGLUMI HBsAg (CLIA) has optimal detection efficacy for HBV subgenotypes samples. The analytical sensitivity is 0.039 IU/mL. The initial diagnostic specificity is 99.63% on blood donors and 96.59% on hospitalized samples. The verification data demonstrated high repeatability, a LoB of 0.02 IU/mL, LoD of 0.05 IU/mL and an excellent linearity of 0.050-250 IU/mL (R2 = 0.9946). The MAGLUMI HBsAg (CLIA) is proved a highly sensitive and reliable assay with optimal subgenotype detection efficacy.

MapGAN: An Intelligent Generation Model for Network Tile Maps.

In recent years, the generative adversarial network (GAN)-based image translation model has achieved great success in image synthesis, image inpainting, image super-resolution, and other tasks. However, the images generated by these models often have problems such as insufficient details and low quality. Especially for the task of map generation, the generated electronic map cannot achieve effects comparable to industrial production in terms of accuracy and aesthetics. This paper proposes a model called Map Generative Adversarial Networks (MapGAN) for generating multitype electronic maps accurately and quickly based on both remote sensing images and render matrices. MapGAN improves the generator architecture of Pix2pixHD and adds a classifier to enhance the model, enabling it to learn the characteristics and style differences of different types of maps. Using the datasets of Google Maps, Baidu maps, and Map World maps, we compare MapGAN with some recent image translation models in the fields of one-to-one map generation and one-to-many domain map generation. The results show that the quality of the electronic maps generated by MapGAN is optimal in terms of both intuitive vision and classic evaluation indicators.

Analysis of UHRF1 expression in human ovarian cancer tissues and its regulation in cancer cell growth.

Ubiquitin-like with PHD and ring finger domains 1 (UHRF1), known as ICB90 or Np95, has been found to be overexpressed in numerous cancers. In this study, we evaluated the expression level of UHRF1 in ovarian cancer. UHRF1 levels in paired ovarian cancer tissues and adjacent normal tissues from 80 ovarian cancer patients were detected using relative quantitatively PCR and Western blot. Small interfering RNA (siRNA) was introduced in two human ovarian cancer cell lines (SKOV-3 and OVCAR-3) to downregulate the expression of UHRF1. The proliferation of siRNA-treated cells was examined using cell counting kit-8 (CCK-8) assay. The growth of these cells showed a remarkable decrease. Moreover, flow cytometric and Hoechst 33342 assays were used to detect the apoptosis. The diagnostic value of UHRF1 messenger RNA (mRNA) expression in ovarian cancer was estimated by receiver-operator characteristic (ROC) curve. The correlation between UHRF1 mRNA expression and clinicopathologic features of ovarian cancer patients was evaluated by χ (2) test. Our results demonstrated that both UHRF1 mRNA and protein were highly expressed in ovarian cancer tissues and significantly higher than that in adjacent normal tissues. Moreover, the inhibition of UHRF1 may lead to cells to undergo apoptosis. Thus, UHRF1 could act as a new oncogenic factor in ovarian cancer and be a potential molecular target for ovarian cancer gene therapy.

Knockdown of UHRF1 by lentivirus-mediated shRNA inhibits ovarian cancer cell growth.

Human UHRF1 (ubiquitin-like PHD and RING finger domain-containing 1) has been reported to be over-expressed in many cancers, but its role in ovarian cancer remains elusive. Here, we determined whether knockdown of UHRF1 by lentivirus-mediated shRNA could inhibit ovarian cancer cell growth. Lentivirus- mediated short hairpin RNAs (lv-shRNAs-UHRF1) were designed to trigger the gene silencing RNA interference (RNAi) pathway. The efficiency of lentivirus-mediated shRNA infection into HO-8910 and HO-8910 PM cells was determined using fluorescence microscopy to observe lentivirus-mediated GFP expressionand was confirmed to be over 80 percent. UHRF1 expression in infected HO-8910 and HO-8910 PM was evaluated by real-time PCR and Western blot analysis. The Cell Counting Kit-8 (CCK-8) assay was used to measure cell viability; flow cytometry and Hoechst 33342 assay was applied to measure cell cycle arrest and apoptosis. Cell invasion was assessed using transwell chambers. Our results demonstrated that the loss of UHRF1 promoted HO-8910 and HO-8910 PM cell apoptosis, while inhibiting cell proliferation. In addition, UHRF1 knockdown significantly inhibited the invasion of human ovarian cancer cells. In the present study, we also showed that depleting HO-8910 cells of UHRF1 caused activation of the DNA damage response pathway, with the cell cycle arrested in G2/M-phase. The DNA damage response in cells depleted of UHRF1 was illustrated by phosphorylation of CHK (checkpoint kinase) 2 on Thr68, phosphorylation of CDC25 (cell division control 25) on Ser 216 and phosphorylation of CDK1 (cyclin-dependent kinase 1) on Tyr 15.

Sensitive colorimetric biosensing for methylation analysis of p16/CDKN2 promoter with hyperbranched rolling circle amplification.

A simple, fast and sensitive colorimetric biosensing method for DNA methylation analysis was developed by combining methylation-sensitive endonuclease based digestion with hyperbranched rolling circle amplification (HRCA) induced signal enhancement. The assay was carried out on a DNA capture probe modified 96-cell microplate with four sequential steps of target recognition, endonuclease-based digestion, isothermal HRCA, and enzyme-catalyzed colorimetric readout within 3h. The semi-quantitative and precise analysis of methylated DNA could be easily achieved by naked eye and absorbance measurements, respectively. The strategy exhibited excellent detection specificity and accuracy with a log-linear response to methylated DNA from 100 fM to 10nM. As a proof of concept, the assay was applied to investigate the methylation status of p16/CDKN2 promoter of breast cancer patients. The methylated p16 concentration was not significantly associated with the clinical parameters. The proposed method allowed efficient methylation detection with simplicity, rapidness, low cost and high sensitivity, showing great promise for application in early diagnosis of methylation-related diseases.

Overexpression of metastasis-associated in colon cancer-1 associated with poor prognosis in patients with esophageal cancer.

Recent studies have shown that expression of metastasis-associated in colon cancer-1(MACC1) is observed in different types of cancer and plays an important role in tumor metastasis. However, the expression of MACC1 and its possible role in esophageal cancer remains unknown. In this study, we determined the expression of MACC1 in esophageal cancer by utilizing immunohistochemistry and analyzed the relationship between the expression and esophageal cancer prognosis. Immunohistochemistry results showed that 47 of 85 cancer lesions (55.2 %) were stained positive, and high expression of MACC1 was correlated with the node metastasis and TNM stage (P < 0.05). The Kaplan-Meier survival curve showed that patients with high MACC1 expression had significantly reduced overall 5-year survival rates (P = 0.004). Cox regression analysis revealed that high expression of MACC1 was associated with increased risk of death (hazard ratio [HR] =2.25) in patients with esophageal cancer. These findings suggested that high expression of MACC1 was correlated with progression and metastasis of esophageal cancer and might serve as a novel prognostic marker for patients with esophageal cancer.

Cellular delivery of quantum dot-bound hybridization probe for detection of intracellular pre-microRNA using chitosan/poly(γ-glutamic acid) complex as a carrier.

A quantum dot (QD)-bound hybridization probe was designed for detection of intracellular pre-miRNA using chitosan (CS)/poly(γ-glutamic acid) (γ-PGA) complex as a gene vector. The probe was prepared by assembling thiolated RNA to gold nanoparticle (Au NP) via Au-S bond and then binding 3'-end amine of the RNA to the carboxy group capped on quantum dot surface. The QD-RNA-Au NP probe was assembled on the vector by mixing with aqueous γ-PGA solution and then CS solution to construct a gene delivery system for highly effective cellular uptake and delivery. After the probe was released from CS/γ-PGA complex to the cytoplasm by electrostatic repulsion at intracellular pH, it hybridized with pre-miRNA precursor as target. The formed product was then cleaved by RNase III Dicer, leading to the separation of QDs from Au NPs and fluorescence emission of QDs, which could be detected by confocal microscopic imaging to monitor the amount of the intracellular pre-miRNA precursor. The in vitro assays revealed that the QD-RNA-Au NP was a robust, sensitive and selective probe for quantitative detection of target pre-miRNA. Using MDA-MB231 and MCF-7 breast cancer cells as models, the relative amount of pre-miRNA let-7a could be successfully compared. Since the amount of miRNA is related to the progress and prognosis of cancer, this strategy could be expected to hold promising application potential in medical research and clinical diagnostics.

Semiconductor quantum dots for biomedicial applications.

Semiconductor quantum dots (QDs) are nanometre-scale crystals, which have unique photophysical properties, such as size-dependent optical properties, high fluorescence quantum yields, and excellent stability against photobleaching. These properties enable QDs as the promising optical labels for the biological applications, such as multiplexed analysis of immunocomplexes or DNA hybridization processes, cell sorting and tracing, in vivo imaging and diagnostics in biomedicine. Meanwhile, QDs can be used as labels for the electrochemical detection of DNA or proteins. This article reviews the synthesis and toxicity of QDs and their optical and electrochemical bioanalytical applications. Especially the application of QDs in biomedicine such as delivering, cell targeting and imaging for cancer research, and in vivo photodynamic therapy (PDT) of cancer are briefly discussed.

[Entamoeba gingivalis infection among college students in Tangshan].

OBJECTIVE: To investigate the prevalence of Entamoeba gingivalis infection in college students in Tangshan, and analyze the relationship between the infection and human behaviors. METHODS: 551 students of grades 1-3 from six colleges in Tangshan received questionnairing, which covered the oral health state, teeth-brushing, xylitol gum-chewing, diet fondness, and smoking. Specimens were taken from the tooth surface of the lesion or fouling materials by using disinfected toothpicks and the smears were observed microscopically to examine Entamoeba gingivalis infection. RESULTS: The prevalence of Entamoeba gingivalis infection was 28.3% (156/551), 30.4% (55/181) and 24.6% in males and females (91/370) respectively (chi2=2.09, P>0.05). The prevalence in students with or without oral disorders was 41.2% (84/204) and 20.8% (72/347) respectively, with a significant statistical difference (chi2=26.41, P<0.01); it was 22.5% (53/236) and 32.7% (103/315) among students who cleaned their teeth regularly or irregularly (chi2=6.97, P<0.01); it was 18.3% (17/93) and 30.4% (139/458) among those usually with or without chewing xylitol gum (chi2=5.55, P<0.05). CONCLUSION: Entamoeba gingivalis infection is common in the college students in Tangshan and it has a close relation to the oral hygiene habits and the presence of oral disorders.