Promising novel biomarkers and therapy targets: The application of cell-free seminal nucleotides in male reproduction research.

Liquid biopsy has the advantage of diagnosing diseases in a non-invasive manner. Seminal plasma contains secretions from the bilateral testes, epididymides, seminal vesicles, bulbourethral glands, and the prostate. These organs are relatively small and contain delicate tubes that are prone to damage by invasive diagnosis. Cell-free seminal nucleic acids test is a newly emerged item in liquid biopsy. Here, we present a comprehensive overview of all known cell-free DNA and cell-free RNAs (mRNA, miRNA, lncRNA, circRNA, piRNA, YRNA, tsRNA, etc.) and discuss their roles as biomarker candidates in liquid biopsy. With great advantages, including high stability, sensitivity, representability, and non-invasiveness, cell-free DNA/RNAs may be developed as promising biomarkers for the screening, diagnosis, prognosis, and follow-up of diseases in semen-secreting organs. Moreover, RNAs in semen may participate in important processes, including sperm maturation, early embryo development, and transgenerational disease inheritance, which may be developed as potential treatment targets for future clinical use.

[Drug Knowledge of Middle School Students in HIV-prone Areas of Liangshan].

OBJECTIVE: To investigate drug knowledge of middle school students in HIV prone areas in Liangshan of Sichuan Province. METHODS: Students were randomly selected from the middle schools located in the HIV prone areas in Liangshan. A questionnaire survey was conducted. Drug knowledge of the respondents and associated factors were analyzed. RESULTS: Of the 10 749 respondents,10.1% had wrong knowledge about drugs. The respondents of male gender and minority ethnicity in the region and those who were in a lower grade,had poor academic records,more sisters,and a schoolmate taking drugs,and lived in a family with HIV infected member were more likely to had poor drug knowledge. By contrast,the respondents who had a peasant father,lived with both parents,resided in a city or township,self-rated in the middle and low 1/3 of wealth,lived in a community with >50% school attendance,and had a family member taking drugs were less likely to have wrong drug knowledge. CONCLUSION: Middle school students in the HIV prone areas in Liangshan have poor drug knowledge. Socioeconomic factors influence the drug knowledge of students,which require systematic interventions.

Randomized controlled study of efficacy and safety of drotaverine hydrochloride in patients with irritable bowel syndrome.

BACKGROUND: This study aimed to assess the efficacy and safety of drotaverine hydrochloride (DHC) in Chinese patients with irritable bowel syndrome (IBS). METHODS: Totally, 144 patients with IBS were included and randomly divided into treatment group and placebo group in a 1:1 ratio. Patients received either DHC or placebo 80-mg tablet, 3 times daily for a total of 4 weeks. The primary outcome included abdominal pain, measured by the visual analog scale (VAS), and weekly stool frequency. The secondary outcomes were measured by the Bristol scale, and the 36-item short form health survey (SF-36), as well as the adverse events recorded during the treatment period. All those outcomes were measured at the end of 4-week treatment. RESULTS: The total and different types of IBS in VAS, stool frequency, and Bristol score were significantly better in the treatment group than those in the placebo group at the end of 4-week treatment. However, no significant difference was found in quality of life, measured by SF-36 scale between 2 groups. Additionally, no serious and significant differences in adverse events were found in and between both groups. CONCLUSION: The findings suggest that DHC has promising efficacy to enhance symptoms of IBS in Chinese population.

A sensitive surface-enhanced Raman scattering enzyme-catalyzed immunoassay of respiratory syncytial virus.

Respiratory viruses have become a major global health challenge which would benefit from advances in screening methods for early diagnosis. Respiratory syncytial virus (RSV) is one of the most important pathogen causing severe lower respiratory tract infections. Here we present a novel surface-enhanced Raman scattering (SERS) enzyme-catalyzed immunoassay of RSV by employing peroxidase substrate 3, 3'-5, 5'-tetramethylbenzidine (TMB) as Raman molecule. Horseradish peroxidase (HRP) attached to the detection antibody in a novel sandwich immunoassay catalyzes the oxidation of TMB by H2O2 to give a radical cation (TMB(+)), which could be easily adsorbed on the negatively charged surface of silver nanoparticles (AgNPs) through electrostatic interaction, inducing the aggregation of AgNPs and thus giving a strong SERS signal. A linear relationship was obtained between the Raman intensity and the amount of RSV in the range from 0.5 to 20 pg/mL, and the minimum detectable concentration of this SERS-based enzyme immunoassay was 0.05 pg/mL, which was 20 times lower than that found in the colorimetric method.

DNA-AuNP networks on cell membranes as a protective barrier to inhibit viral attachment, entry and budding.

Viral infections have caused numerous diseases and deaths worldwide. Due to the emergence of new viruses and frequent virus variation, conventional antiviral strategies that directly target viral or cellular proteins are limited because of the specificity, drug resistance and rapid clearance from the human body. Therefore, developing safe and potent antiviral agents with activity against viral infection at multiple points in the viral life cycle remains a major challenge. In this report, we propose a new modality to inhibit viral infection by fabricating DNA conjugated gold nanoparticle (DNA-AuNP) networks on cell membranes as a protective barrier. The DNA-AuNPs networks were found, via a plaque formation assay and viral titers, to have potent antiviral ability and protect host cells from human respiratory syncytial virus (RSV). Confocal immunofluorescence image analysis showed 80 ± 3.8% of viral attachment, 91.1 ± 0.9% of viral entry and 87.9 ± 2.8% of viral budding were inhibited by the DNA-AuNP networks, which were further confirmed by real-time fluorescence imaging of the RSV infection process. The antiviral activity of the networks may be attributed to steric effects, the disruption of membrane glycoproteins and limited fusion of cell membrane bilayers, all of which play important roles in viral infection. Therefore, our results suggest that the DNA-AuNP networks have not only prophylactic effects to inhibit virus attachment and entry, but also therapeutic effects to inhibit viral budding and cell-to-cell spread. More importantly, this proof-of-principle study provides a pathway for the development of a universal, broad-spectrum antiviral therapy.

In situ labelling chemistry of respiratory syncytial viruses by employing the biotinylated host-cell membrane protein for tracking the early stage of virus entry.

An in situ labelling strategy was proposed to produce quantum dot-labelled respiratory syncytial viruses (RSVs) by incorporating the biotinylated membrane protein of the host cells into mature virions, followed by conjugation with streptavidin modified quantum dots (SA-QDs), which has the advantages such as convenience, efficiency and minor influence on viral infectivity and thus could be successfully applied to track the early stage of virus entry.

Real-time light scattering tracking of gold nanoparticles- bioconjugated respiratory syncytial virus infecting HEp-2 cells.

Real-time tracking of virus invasion is crucial for understanding viral infection mechanism, which, however, needs simple and efficient labeling chemistry with improved signal-to-noise ratio. For that purpose, herein we investigated the invasion dynamics of respiratory syncytial virus (RSV) through dark-field microscopic imaging (iDFM) technique by using Au nanoparticles (AuNPs) as light scattering labels. RSV, a ubiquitous, non-segmented, pleiomorphic and negative-sense RNA virus, is an important human pathogen in infants, the elderly, and the immunocompromised. In order to label the enveloped virus of paramyxoviridae family, an efficient streptavidin (SA)-biotin binding chemistry was employed, wherein AuNPs and RSV particles modified with SA and biotin, respectively, allowing the AuNP-modified RSVs to maintain their virulence without affecting the native activities of RSV, making the long dynamic visualization successful for the RSV infections into human epidermis larynx carcinoma cells.

A general quantitative pH sensor developed with dicyandiamide N-doped high quantum yield graphene quantum dots.

A general quantitative pH sensor for environmental and intracellular applications was developed by the facile hydrothermal preparation of dicyandiamide (DCD) N-doped high quantum yield (QY) graphene quantum dots (GQDs) using citric acid (CA) as the carbon source. The obtained N-doped GQDs have excellent photoluminesence (PL) properties with a relatively high QY of 36.5%, suggesting that N-doped chemistry could promote the QY of carbon nanomaterials. The possible mechanism for the formation of the GQDs involves the CA self-assembling into a nanosheet structure through intermolecular H-bonding at the initial stage of the reaction, and then the pure graphene core with many function groups formed through the dehydration between the carboxyl and hydroxyl of the intermolecules under hydrothermal conditions. These N-doped GQDs have low toxicity, and are photostable and pH-sensitive between 1.81 to 8.96, giving a general pH sensor with a wide range of applications from real water to intracellular contents.

Hydrophilic Cu2-xSe/reduced graphene oxide nanocomposites with tunable plasmonic properties and their applications in cellular dark-field microscopic imaging.

A facile aqueous chemical approach is developed for one-pot synthesis of the nanocomposites of heavily doped semiconductor nanoparticles (Cu2-xSe NPs) and reduced graphene oxide (rGO) at room temperature, wherein the reduction of GO and the in situ growth of Cu2-xSe NPs on rGO sheets occur simultaneously. The as-prepared Cu2-xSe/rGO nanocomposites exhibit a well-defined near-infrared (NIR) localized surface plasmon resonance (LSPR), which arises from free carriers (holes) and could be tuned from 1360 to 1050 nm by varying the reaction time, owing to the increase of the free carrier density in the valence band of Cu2-xSe NPs. This approach not only offers an efficient strategy to synthesize the self-doped Cu2-xSe/rGO nanocomposites with strong and tunable NIR absorption, but also develops new light scattering nanoprobes with good biocompatibility as well as unique optical properties for in vitro cellular dark-field microscopic imaging (iDFM).