Rapid detection of Mycobacterium tuberculosis based on cyp141 via real-time fluorescence loop-mediated isothermal amplification (cyp141-RealAmp).

Background: The rapid detection of Mycobacterium tuberculosis (MTB) is essential for controlling tuberculosis. We designed a portable thermocycler-based real-time fluorescence loop-mediated isothermal amplification assay (cyp141-RealAmp) using six oligonucleotide primers derived from cyp141 to detect MTB. A combined number of 213 sputum samples (169 obtained from clinically diagnosed cases of pulmonary TB and 44 from a control group without tuberculosis) underwent Acid-fast bacillus (AFB) smear, culture, Xpert MTB/RIF assays, and cyp141-RealAmp assay.

Evaluation of an identification method for the SARS-CoV-2 Delta variant based on the amplification-refractory mutation system.

The Delta variant of SARS-CoV-2 dominated the COVID-19 pandemic due to its high viral replication capacity and immune evasion, causing massive outbreaks of cases, hospitalizations, and deaths. Currently, variant identification is performed mainly by sequencing. However, the high requirements for equipment and operators as well as its high cost have limited its application in underdeveloped regions.

Identification of integrase inhibitor-related drug resistance mutations in newly diagnosed ART-naïve HIV patients.

Background: In China, the recommended treatment regimens for HIV-infected individuals were tenofovir in combination with lamivudine or emtricitabine as NRTIs, efavirenz or rilpivirine as NNRTIs, lopinavir/ritonavir as protease inhibitors, and raltegravir or dolutegravir as INSTIs. The development of drug resistance increases the risk of viral rebound, opportunistic infections, and ultimately treatment failure such that the early detection of resistance is ideal. This study was developed to explore primary drug resistance characteristics and genotypic distributions in newly diagnosed antiretroviral therapy (ART)-naïve HIV-1 patients in Nanjing with the goal of establishing a basis for their individualized treatment in the clinic.

Epidemiology of Nontuberculous Mycobacteria in Nanjing and Mutations Associated with Clofazimine Resistance in .

Background: Nontuberculous mycobacteria (NTM) are easily misdiagnosed as multidrug-resistant tuberculosis (MDR-TB), and treatment drugs are very limited. The main objective of our study was to evaluate the minimal inhibitory concentration (MIC) in vitro of bedaquiline (BDQ), clofazimine (CFZ), linezolid (LZD), delamanid (DLM), and pretomanid (PA-824) for treatment of and . Furthermore, we determined whether , and were related to drug resistance to provide an experimental basis for the use of these five drugs in the treatment of NTM.

Numerical Simulation in the Melt Pool Evolution of Laser Powder Bed Fusion Process for Ti6Al4V.

In order to track the free interface of the melt pool and understand the evolution of the melt pool, the flow of fluid, and the interface behavior of gas and liquid, a physical model is developed by using the VOF method in this paper. Its characteristics are a combined heat source model, including a parabolic rotation and a cylindrical distribution, and a powder bed stochastic distributed model with powder particle size. The unit interface between the metallic and gas phase in the laser-powder interaction zone can only be loaded by the heat source.

SARS-CoV-2 detection using quantum dot fluorescence immunochromatography combined with isothermal amplification and CRISPR/Cas13a.

The development of reliable, sensitive, and fast devices for the diagnosis of COVID-19 is of great importance in the pandemic of the new coronavirus. Here, we proposed a new principle of analysis based on a combination of reverse transcription and isothermal amplification of a fragment of the gene encoding the S protein of the SARS-CoV-2 and the CRISPR/Cas13a reaction for cleavage of the specific probe. As a result, the destroyed probe cannot be detected on an immunochromatographic strip using quantum fluorescent dots.

Amplification-free smartphone-based attomolar HBV detection.

Classical gold standard HBV detection relies on expensive devices and complicated procedures, thus is always restricted in large-scale hospitals and centers for disease control and prevention. To extend HBV detection to primary clinics especially in underdeveloped areas, we design amplification-free smartphone-based attomolar HBV detecting technique based on single molecule sensing. Verified by synthesized HBV target DNA, this technique reaches a detection limit at attomolar concentration (100 aM); and verified by 110 clinical samples, it also reaches a rather high sensitivity of 10 copy/mL (≈2000 IU/mL) with a high accuracy of 93.

Development of a Novel Bioluminescence Pyrophosphate Assay for the High-Sensitivity Detection of Hepatitis B Virus.

The transmission of bloodborne viruses through transfusion remains a major blood supply-related safety concern, with hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) being the most important pathogens in this context. Real-time bioluminescent pyrophosphate testing has been developed as a means of readily detecting bacterial cells within particular sample types without requiring the use of expensive or complex instrumentation. The sensitivity of this approach, however, is often limited such that it is not compatible with many potential applications.

Clinical application of thioredoxin reductase as a novel biomarker in liver cancer.

Hepatic cancer is often amenable to surgery, including percutaneous ablation, trans-arterial chemoembolization. However, in metastatic cases, surgery is often not an effective option. Chemotherapy as a conventional clinical method for treatment of malignant diseases may be useful in such cases, but it is likewise not always able to slow or halt progression, therefore novel approaches for treatment of hepatic cancer are needed.

Telomerase inhibition decreases esophageal squamous carcinoma cell migration and invasion.

Telomerase has been shown to be associated with a variety of cancer types. To elucidate the role of telomerase in esophageal squamous carcinoma (ESCC), tissue samples from 100 patients with ESCC, and paired paracancerous tissues from 75 of these patients, were collected for use in the present study. Using immunohistochemical analysis, the expression of telomerase reverse transcriptase (hTERT) in the cytoplasm of ESCC cells was revealed to be significantly higher compared with that in paracancerous tissues, and no significant difference was observed between hTERT expression in the nucleus of ESCC and paracancerous tissue cells.

Effects of methyl oleate and microparticle-enhanced cultivation on echinocandin B fermentation titer.

Echinocandin B (ECB) is a key precursor of antifungal agent Anidulafungin, which has demonstrated clinical efficacy in patients with invasive candidiasis. In this study, the effects of microparticle-enhanced cultivation and methyl oleate on echinocandin B fermentation titer were investigated. The results showed that the titer was significantly influenced by the morphological type of mycelium, and mycelium pellet was beneficial to improve the titer of this secondary metabolism.

Quantitative protein detection using single molecule imaging enzyme-linked immunosorbent assay (iELISA).

Protein detection is a key step in molecular biology research and is required for pathogen and protein marker testing for disease diagnostics. Here, single molecule imaging enzyme-linked immunosorbent assay (iELISA) is proposed to quantitatively measure the porcine circovirus type 2 (PCV2) Cap protein. The monoclonal antibody against PCV2 Cap protein indirectly immobilized on a polyethylene glycol (PEG) passivated slide by biotin-streptavidin interaction is used to capture the PCV2 Cap protein, and the PCV2 Cap protein can be detected in single molecule level according to the fluorescein isothiocyanate (FITC)-labeled secondary antibody using total internal reflection fluorescence microscopy.

Quantitative Detection and Real-Time Monitoring of Endogenous mRNA at the Single Live Cell Level Using a Ratiometric Molecular Beacon.

Messenger ribonucleic acid (mRNA) plays an important role in various cellular processes. however, traditional techniques cannot realize mRNA detections in live cells as they rely on mRNA purification or cell fixation. To achieve real-time and quantitative mRNA detections at a single live cell level, a single-strand stem-loop-structured ratiometric molecular beacon (RMB) composed of the phosphorothioate-modified loop domain on the 2'--methyl RNA backbone with a reporter dye, quencher, and reference dye is proposed to detect the Hsp27 mRNA as a modeled endogenous mRNA.

On-site cell concentration and viability detections using smartphone based field-portable cell counter.

We designed a smartphone based field-portable cell counter combining the smartphone microscope for bright-field image recording and the smartphone application for automatically cell recognition, counting and analysis. To our best knowledge, it is the first time that a smartphone based cell counter can distinguish and count both live and dead cells simultaneously. Compared to the results obtained by hemocytometer, commercial cell counter and flow cytometer, the proposed device was proved to detect cell concentration and viability accurately within the application range between 10 cells/mL and 10 cells/mL.

Wnt5a induces ROR1 and ROR2 to activate RhoA in esophageal squamous cell carcinoma cells.

Wnt5a is a nontransforming Wnt family member and identified as an oncogenic role on cell motility of breast cancer and glioblastoma. However, Wnt5a signaling in esophageal squamous cell carcinoma (ESCC) progression remains poorly defined. Immunohistochemistry assays were used to measure the Wnt5a expression in ESCC sections.

On-site quantitative Hg measurements based on selective and sensitive fluorescence biosensor and miniaturized smartphone fluorescence microscope.

Mercury is a bio-accumulative and toxic pollutant causing severe damages to human health and environment. Since Hg is the most stable form of mercury, selective and sensitive Hg detection is required. Though classical approaches can realize accurate Hg detection, the complicated instruments and the time-consuming operations inevitably limit their on-site applications.

Real-time analysis of quantum dot labeled single porcine epidemic diarrhea virus moving along the microtubules using single particle tracking.

In order to study the infection mechanism of porcine epidemic diarrhea virus (PEDV), which causes porcine epidemic diarrhea, a highly contagious enteric disease, we combined quantum dot labeled method, which could hold intact infectivity of the labeled viruses to the largest extent, with the single particle tracking technique to dynamically and globally visualize the transport behaviors of PEDVs in live Vero cells. Our results were the first time to uncover the dynamic characteristics of PEDVs moving along the microtubules in the host cells. It is found that PEDVs kept restricted motion mode with a relatively stable speed in the cell membrane region; while performed a slow-fast-slow velocity pattern with different motion modes in the cell cytoplasm region and near the microtubule organizing center region.

Simulation of the microstructural characteristics of saltwater turbulence in a water tank.

This study simulated the generation and evolution of saltwater turbulence within a water tank. By pouring fresh water over saltwater in the tank, a layer of saline water with a fixed gradient was created. Convective turbulence was then formed by heating the bottom of the tank.

Hydrolysis before Stir-Frying Increases the Isothiocyanate Content of Broccoli.

Broccoli is found to be a good source of glucosinolates, which can be hydrolyzed by endogenous myrosinase to obtain chemopreventive isothiocyanates (ITCs); among them, sulforaphane (SF) is the most important agent. Studies have shown that cooking greatly affects the levels of SF and total ITCs in broccoli. However, the stability of these compounds during cooking has been infrequently examined.

Baicalin alleviates radiation-induced epithelial-mesenchymal transition of primary type II alveolar epithelial cells via TGF-β and ERK/GSK3β signaling pathways.

Background: Radiation therapy is commonly used to treat thoracic malignancies. However, it may lead to severe lung pneumonitis and ultimately fibrosis. Irradiation has been reported to increase epithelial-mesenchymal transition (EMT) of type II alveolar epithelial cells (AEC), which play an important role in pulmonary fibrosis.

High Seroprevalence of Human Herpesvirus 8 Infection in HIV-positive Homosexual Men in Jiangsu Province, China.

Background: HIV-infected homosexual men are more frequently diagnosed with Kaposi's sarcoma. With the increase of HIV-infected homosexual men in China, we urgently need to know the KS-related human herpesvirus (KSHV/HHV-8) seroprevalence in this population. To investigate HHV-8 prevalence among HIV-positive homosexual men, we recruited 183 patients naive of antiretroviral therapy (ART) whose blood samples presented with HIV-antibody positive as confirmed by western blot.

Profile of HBV polymerase gene mutations during entecavir treatment in patients with chronic hepatitis B.

Background/aims: We investigated the efficacy of entecavir (ETV) monotherapy in 54 naïve patients and 27 lamivudine (LMV) and/or adefovir (ADV) experienced patients.

Methods: Eighty-one chronic hepatitis B patients with a viral load above 4 log 10 copies/ml and high levels of serum alanine aminotransferase were treated with ETV 0.5mg daily.

Mutation of DNA Polymerase β R137Q Results in Retarded Embryo Development Due to Impaired DNA Base Excision Repair in Mice.

DNA polymerase β (Pol β), a key enzyme in the DNA base excision repair (BER) pathway, is pivotal in maintaining the integrity and stability of genomes. One Pol β mutation that has been identified in tumors, R137Q (arginine to glutamine substitution), has been shown to lower polymerase activity, and impair its DNA repair capacity. However, the exact functional deficiency associated with this polymorphism in living organisms is still unknown.