Rapid lateral flow immunoassay for the fluorescence detection of SARS-CoV-2 RNA.

The coronavirus disease 2019 (COVID-19) pandemic has highlighted the need for rapid and accurate nucleic acid detection at the point of care. Here, we report an amplification-free nucleic acid immunoassay, implemented on a lateral flow strip, for the fluorescence detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in less than one hour. The assay uses DNA probes that are designed to bind to the conserved open reading frame 1ab (ORF1ab), envelope protein (E) and the nucleocapsid (N) regions of the SARS-CoV-2 genome, and a fluorescent-nanoparticle-labelled monoclonal antibody that binds to double-stranded DNA-RNA hybrids.

The transmissibility of hepatitis C virus: a modelling study in Xiamen City, China.

This study aimed at estimating the transmissibility of hepatitis C. The data for hepatitis C cases were collected in six districts in Xiamen City, China from 2004 to 2018. A population-mixed susceptible-infectious-chronic-recovered (SICR) model was used to fit the data and the parameters of the model were calculated.

A novel near-infrared light-responsive photoelectrochemical platform for detecting microcystin-LR in fish based on AgS cubes and plasmonic Au nanoparticles.

As a main contaminant in fish, microcystin-LR (MC-LR) leads to serious liver problems; therefore, the development of MC-LR sensors is important to guarantee aquatic food safety. In this work, a near-infrared (NIR) light-excited photoelectrochemical (PEC) immunosensor was developed through conjugation of AgS cubes with Au nanoparticles (NPs) to determine MC-LR residues in fish. Specifically, as a narrow-band semiconducting material, AgS is capable of absorbing NIR light.

Epidemiology of tsutsugamushi disease and its relationship with meteorological factors in Xiamen city, China.

Tsutsugamushi disease (TD) is an acute infectious disease caused by Orientia tsutsugamushi. This study aimed to analyze the epidemiological features of TD, investigate chigger mites and their hosts, and investigate the meteorological factors affecting TD incidence and the host of O. tsutsugamushi in Xiamen city, China.

Prognostic value of nutritional impairment on treatment-related toxicity and survival in patients with nasopharyngeal carcinoma taking normal nutrition before radiotherapy.

Background: To investigate nutritional impairment during intensity-modulated radiotherapy (IMRT) in patients with nasopharyngeal carcinoma (NPC) taking normal nutrition before IMRT and its effect on treatment-related toxicities (TRTs) and survival.

Methods: Modified nutrition index (m-NI) of 187 patients with NPC, comprised eight indicators (body mass index, circumference of upper arm muscles, total lymphocyte count, red blood cell count, levels of albumin, pre-albumin, transferrin, and hemoglobin), were evaluated before/after IMRT. Patient characteristics, m-NI, and the follow-up data for survival and TRTs were analyzed.

Sulfur and phosphorus co-doped graphene quantum dots for fluorescent monitoring of nitrite in pickles.

Doping graphene quantum dots (GQDs) with heteroatoms can change their band gap and electronic density, thus enhancing their fluorescence quantum yield (QY). In this work, we for the first time reported a nontoxic, rapid, and one-pot hydrothermal method to synthesize sulfur and phosphorus co-doped GQDs (S, P-GQDs). Citric acid was functioned as a carbon source, whereas sodium phytate and anhydrous sodium sulfate are used as the P and S sources, respectively, in this bottom-up synthesis.

Development of an efficient neutralization assay for Coxsackievirus A10.

Coxsackievirus A10 (CVA10) recently has become one of the major pathogens of hand, foot, and mouth disease (HFMD) in children worldwide, but no cure or vaccine against CVA10 is available yet. Serological evaluation of herd immunity to CVA10 will promote the development of vaccine. The traditional neutralization assay based on inhibition of cytopathic effect (Nt-CPE) is a common method for measuring neutralizing antibody titer against CVA10, which is time-consuming and labor-intensive.

Phosphorus and chlorine co-doped carbon dots with strong photoluminescence as a fluorescent probe for ferric ions.

Usually, carbon dots (CDs) display a relatively weak fluorescence quantum yield (QY). In order to obtain brighter CDs, phosphorus and chlorine co-doped CDs (P,Cl-CDs) were prepared via hydrothermal treatment of maltose in the presence of phosphoric and hydrochloric acids. The new CDs are highly monodispersed in water solution, have high fractions of P (14.

Rapid Identification of Clinically Relevant Species by Multicolor Melting Curve Analysis.

The sustained increase in the incidence of nontuberculous mycobacterial (NTM) infection and the difficulty in distinguishing these infections from tuberculosis constitute an urgent need for NTM species-level identification. The MeltPro Myco assay is the first diagnostic system that identifies 19 clinically relevant mycobacteria in a single reaction based on multicolor melting curve analysis run on a real-time PCR platform. The assay was comprehensively evaluated regarding its analytical and clinical performances.

Development of multiplex real-time reverse-transcriptase polymerase chain reaction assay for simultaneous detection of Zika, dengue, yellow fever, and chikungunya viruses in a single tube.

Zika virus (ZIKV), dengue virus (DENV), chikungunya virus (CHIKV) and yellow fever virus (YFV) share the same mosquito vectors and have similar clinical manifestations early stage of infection. Therefore, simultaneously differentiating these viruses from each other is necessary. We developed a multiplex real-time reverse-transcriptase polymerase chain reaction (RT-PCR) assay for the differentiation of these four viruses in a single tube.

McSpoligotyping, a One-Step Melting Curve Analysis-Based Protocol for Spoligotyping of Mycobacterium tuberculosis.

The direct repeat (DR) region in the (MTB) genome is composed of highly polymorphic direct variant repeats, which are the basis of spacer oligonucleotide typing (spoligotyping) to study the population structure and epidemiology of However, the membrane hybridization-based detection format requires various post-PCR manipulations and is prone to carryover contamination, restricting its wide use in high-TB-burden and resource-limited countries. We developed a one-step spoligotyping protocol, termed McSpoligotyping, based on real-time PCR. The typing results can be generated within 3 h by a single step of DNA addition.

An emerging and expanding clade accounts for the persistent outbreak of Coxsackievirus A6-associated hand, foot, and mouth disease in China since 2013.

Enterovirus (EV)-A71 and Coxsackievirus (CV)-A16 have historically been the major pathogens of hand, foot, and mouth disease (HMFD) in China; however, CV-A6， which had previously received little attention, became the predominant pathogen in 2013, and has remained one of the common pathogens since then. In this work, we conducted a molecular epidemiology study of CV-A6-associated HFMD in Xiamen from 2009 to 2015. The data showed CV-A6 pandemics had a certain periodicity rather than occurring randomly.

A Rapid On-Site Assay for the Detection of Influenza A by Capillary Convective PCR.

Background: Morbidity and mortality from influenza A (Flu A) have increased in recent years. Timely diagnosis and management are critical for disease control. Therefore, the development of a rapid, accurate, and portable analytical method for on-site analysis is imperative.

Serological survey of neutralizing antibodies to eight major enteroviruses among healthy population.

Human enteroviruses (EVs) are the most common causative agents infecting human, causing many harmful diseases, such as hand, foot, and mouth disease (HFMD), herpangina (HA), myocarditis, encephalitis, and aseptic meningitis. EV-related diseases pose a serious worldwide threat to public health. To gain comprehensive insight into the seroepidemiology of major prevalent EVs in humans, we firstly performed a serological survey for neutralizing antibodies (nAbs) against Enterovirus A71 (EV-A71), Coxsackie virus A16 (CV-A16), Coxsackie virus A6 (CV-A6), Coxsackie virus A10 (CV-A10), Coxsackie virus B3 (CV-B3), Coxsackie virus B5 (CV-B5), Echovirus 25 (ECHO25), and Echovirus 30 (ECHO30) among the healthy population in Xiamen City in 2016, using micro-neutralization assay.

The Association between NFKBIA Polymorphisms and the Progression of Chronic Hepatitis B Virus Infection among the Chinese Han Population.

Based on the involvement of nuclear factor-κB inhibitor alpha (NFKIBA) in the NF-κ B pathway, which is closely related to host immunity, we evaluated whether NFKIBA polymorphisms are associated with the disease progression of chronic hepatitis B virus (HBV) infection. We collected blood samples from a total of 212 treatment-naïve patients with chronic HBV infection. NFKBIA polymorphisms were determined by Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry.

Dissemination and Molecular Characterization of at a Tertiary Referral Hospital in Xiamen City, China.

is a global epidemic pathogen that causes heavy disease burden. The aim of this study was to determine which globally known lineages are currently present in a hospital of Xiamen. Therefore, the 426 strains were detected by Melting Curve Analysis (MCA) and genotyped by Pulsed Field Gel Electrophoresis (PFGE) as well as Multicolor Melting Curve Analysis-Based Multilocus Melt Typing (MLMT).

A sensitive bisphenol A voltammetric sensor relying on AuPd nanoparticles/graphene composites modified glassy carbon electrode.

In this work, a sensitive bisphenol A (BPA) electrochemical sensor was assembled using a surfactant-free AuPd nanoparticles-loaded graphene nanosheets (AuPdNPs/GNs) modified electrode. The AuPdNPs monodispersed on GNs were successfully prepared by the spontaneous redox reaction between bimetallic precursors and GNs. Because no surfactant or halide ions were involved in the proposed synthesis, the prepared composite was enabled to directly modify a glassy carbon electrode without any pre-treatments.

Serological Prevalence Against Japanese Encephalitis Virus-Serocomplex Flaviviruses in Commensal and Field Rodents in South China.

Background: Japanese encephalitis caused by Japanese encephalitis virus (JEV) is an endemic zoonotic disease of high public health importance in the Asian Pacific region. The aim of this study was to investigate the presence of JEV infection in commensal and field rodents in South China.

Materials And Methods: RNA copies of JEV were detected in brain samples of rodents using real-time RT-PCR.

Association study between mannose-binding lectin haplotypes and X gene mutation of hepatitis B virus from treatment naïve patients.

Mannose binding lectin (MBL) plays important role in the innate immunity of human. Mutations in the MBL2 gene can significantly change the serum level of MBL, and consequently alter the susceptibility and progression of infectious disease. However, the association between the MBL2 profile and the HBV mutation and quasispecies complexity has not yet been reported.

Microarray analysis on the lncRNA expression profile in male hepatocelluar carcinoma patients with chronic hepatitis B virus infection.

Long non-coding RNAs are involved with development and progression of cancer, and the advance of microarray technology allows the researchers to investigate the complete expression profile of lncRNA in various kinds of sample. We enrolled 5 male primary HCC cases with chronic HBV infection and the HCC and normal tissues have been obtained during the resection surgery. After total RNA extraction, the lncRNA microarray analysis was conducted to determine the lncRNA and mRNA expression signals.

Association between Toll-Like Receptor 4 Polymorphisms and Systemic Lupus Erythematosus Susceptibility: A Meta-Analysis.

Family aggregation was observed among systemic lupus erythematosus (SLE) cases, suggesting the genetic factor may contribute to the susceptibility. Toll-like receptors (TLR) play key role in human immune system; in order to gain better insight on the association between TLR4 polymorphisms and SLE risk, a meta-analysis was conducted. In total 4 case-control studies have been included, involving 503 SLE cases and 636 healthy controls.

Association between mannose-binding lectin variants, haplotypes and risk of hepatocellular carcinoma: A case-control study.

The innate immunity gene mannose-binding lectin2 (MBL2) has played an important role in hepatitis B virus (HBV) infection, and the relationship between MBL2 variants and hepatocellular carcinoma (HCC) risk has not yet been identified. In total, 315 HCC cases and 315 healthy controls were enrolled and blood samples were acquired. High resolution melt analysis (HRM) was employed to genotype 6 polymorphisms in MBL2 gene.

Spoligotyping of Mycobacterium tuberculosis Complex Isolates by Use of Ligation-Based Amplification and Melting Curve Analysis.

We report here a ligation-based spoligotyping that can identify unamplified spacers in membrane-based spoligotyping due to asymmetric insertion of IS6110 in the direct repeat locus. Our typing yielded 84.4% (411/487) concordance with traditional typing and 100% (487/487) accuracy when confirmed by DNA sequencing.

Determination of MIC Breakpoints for Second-Line Drugs Associated with Clinical Outcomes in Multidrug-Resistant Tuberculosis Treatment in China.

Our study aims to identify the clinical breakpoints (CBPs) of second-line drugs (SLDs) above which standard therapy fails in order to improve multidrug-resistant tuberculosis (MDR-TB) treatment. MICs of SLDs were determined for M. tuberculosis isolates cultured from 207 MDR-TB patients in a prospective cohort study in China between January 2010 and December 2012.