Advanced Fog Harvesting Method by Coupling Plasma and Micro/Nano Materials.

Harvesting fog is a potential and effective way to alleviate the crisis of water resource shortage. A highly efficient and economical fog harvesting method has always been a global and common goal. Here, a promising fog harvesting method by coupling plasma and micro/nano materials is proposed, which can achieve 93% fog collection efficiency with consuming power of only 0.76 W/0.04 m2. The basic method is to utilize nanoparticles to decorate both the discharge electrode and the collecting electrode of the micro/nano electrostatic fog collector. For the discharge electrode, the nanoparticles can achieve an order of magnitude higher electric field strength and a 28.6% decrease in the operating voltage (14 kV decreases to 10 kV). For the collecting electrode, a novel composite structure of hydrophobic/hydrophilic (HB/HL) is proposed. The core advantage is the directional droplet transport at the junction of HB and HL caused by surface tension can adjust the accumulated droplets on the two sides, which avoids the droplet residue and mesh blockage in the general structure. This technology provides an innovative approach for the collection of microdroplets and a new design idea for the fog collector to deal with the water crisis.

Rapid detection of Mucorales based on recombinase polymerase amplification and real-time PCR.

Mucormycosis, an invasive fungal disease with severe consequences, poses a significant threat to immunocompromised individuals. However, the timely and accurate identification of Mucorales infection continues to present difficulties. In this study, novel detection techniques utilizing recombinase polymerase amplification (RPA) and quantitative real-time polymerase chain reaction (qPCR) were developed, specifically targeting the mitochondrial rnl gene, in order to address this challenge. The specificity of the RPA and qPCR assay was assessed by adding genomic DNAs extracted from 14 non-targeted strains, as well as human and mouse blood. No false-positive results were observed. Additionally, genomic DNAs from 13 species in five genera of order Mucorales were tested and yielded positive results in both methods. To further evaluate the sensitivity of the assays, DNAs from Rhizopus oryzae, Mucor racemosus, Absidia glauca, Rhizomucor miehei, and Cunninghamella bertholletiae were utilized, with concentrations ranging from 1 ng/µL to 1 fg/µL. The limit of detection (LoD) for the RPA assay was determined to be 1 pg., with the exception of Rhizomucor miehei which had a LoD of 1 ng. The LoD for the qPCR assay varied between 10 fg and 1 pg., depending on the specific species being tested. Sensitivity analysis conducted on simulated clinical samples revealed that the LoD for RPA and qPCR assays were capable of detecting DNA extracted from 103 and 101 colony forming units (CFU) conidia in 200 µL of blood and serum, respectively. Consequently, the real-time RPA and qPCR assays developed in this study exhibited favorable sensitivity and specificity for the diagnosis of mucormycosis.

Involvement of JNK signaling in Aspergillus fumigatus-induced inflammatory factors release in bronchial epithelial cells.

Aspergillus fumigatus (A. fumigatus) is an important fungal pathogen and its conidia can be inhaled and interact with airway epithelial cells; however, the release of inflammatory factors from bronchial epithelial cells upon A. fumigatus infection and its regulation remained unclear. Here it was demonstrated that the release of IL-27, MCP-1 and TNF-α from BEAS-2B cells were upregulated upon stimulation by conidia, while mitogen-activated protein kinase signaling pathway was activated. Further, the inhibition of JNK, but not p38 and ERK, could inhibit inflammatory factors release and the LC3II formation in BEAS-2B cells induced by A. fumigatus conidia. In addition, an inhibitor of autophagy, bafilomycin A1 was able to significantly down-regulate the release of inflammatory factors in BEAS-2B cells upon A. fumigatus conidia, while rapamycin could reverse the effect of JNK inhibitor on IL-27 and TNF-α release. Taken together, these data demonstrated that JNK signal might play an important role in inflammatory factor release regulated by autophagy in bronchial epithelial cells against A. fumigatus infection.

Effects of neurotransmitter receptor antagonists on sea urchin righting behavior and tube foot motility.

Echinoderms, such as sea urchins, occupy an interesting position in animal phylogeny in that they are genetically closer to vertebrates than the vast majority of all other invertebrates but have a nervous system that lacks a brain or brain-like structure. Despite this, very little is known about the neurobiology of the adult sea urchin, and how the nervous system is utilized to produce behavior. Here, we investigated effects on the righting response of antagonists of ionotropic receptors for the neurotransmitters acetylcholine, GABA and glycine, and antagonists of metabotropic receptors for the amines dopamine and noradrenaline (norepinephrine). Antagonists slowed the righting response in a dose-dependent manner, with a rank order of potency of strychnine>haloperidol>propranolol>bicuculline>hexamethonium, with RT50 values (concentrations that slowed righting time by 50%) ranging from 4.3 µmol l-1 for strychnine to 7.8 mmol l-1 for hexamethonium. The results also showed that both glycine and adrenergic receptors are needed for actual tube foot movement, and this may explain the slowed righting seen when these receptors were inhibited. Conversely, inhibition of dopamine receptors slowed the righting response but had no effect on tube foot motility, indicating that these receptors play roles in the neural processing involved in the righting behavior, rather than the actual physical righting. Our results identify the first effects of inhibiting the glycinergic, dopaminergic and adrenergic neurotransmitter systems in adult sea urchins and distinguish between the ability of sea urchins to right themselves and their ability to move their tube feet.

Application of Machine Learning Classifier to Candida auris Drug Resistance Analysis.

Candida auris (C. auris) is an emerging fungus associated with high morbidity. It has a unique transmission ability and is often resistant to multiple drugs. In this study, we evaluated the ability of different machine learning models to classify the drug resistance and predicted and ranked the drug resistance mutations of C. auris. Two C. auris strains were obtained. Combined with other 356 strains collected from the European Bioinformatics Institute (EBI) databases, the whole genome sequencing (WGS) data were analyzed by bioinformatics. Machine learning classifiers were used to build drug resistance models, which were evaluated and compared by various evaluation methods based on AUC value. Briefly, two strains were assigned to Clade III in the phylogenetic tree, which was consistent with previous studies; nevertheless, the phylogenetic tree was not completely consistent with the conclusion of clustering according to the geographical location discovered earlier. The clustering results of C. auris were related to its drug resistance. The resistance genes of C. auris were not under additional strong selection pressure, and the performance of different models varied greatly for different drugs. For drugs such as azoles and echinocandins, the models performed relatively well. In addition, two machine learning algorithms, based on the balanced test and imbalanced test, were designed and evaluated; for most drugs, the evaluation results on the balanced test set were better than on the imbalanced test set. The mutations strongly be associated with drug resistance of C. auris were predicted and ranked by Recursive Feature Elimination with Cross-Validation (RFECV) combined with a machine learning classifier. In addition to known drug resistance mutations, some new resistance mutations were predicted, such as Y501H and I466M mutation in the ERG11 gene and R278H mutation in the ERG10 gene, which may be associated with fluconazole (FCZ), micafungin (MCF), and amphotericin B (AmB) resistance, respectively; these mutations were in the "hot spot" regions of the ergosterol pathway. To sum up, this study suggested that machine learning classifiers are a useful and cost-effective method to identify fungal drug resistance-related mutations, which is of great significance for the research on the resistance mechanism of C. auris.

Long Terminal Repeat Retrotransposon Afut4 Promotes Azole Resistance of Aspergillus fumigatus by Enhancing the Expression of sac1 Gene.

Aspergillus fumigatus causes a series of invasive diseases, including the high-mortality invasive aspergillosis, and has been a serious global health threat because of its increased resistance to the first-line clinical triazoles. We analyzed the whole-genome sequence of 15 A. fumigatus strains from China and found that long terminal repeat retrotransposons (LTR-RTs), including Afut1, Afut2, Afut3, and Afut4, are most common and have the largest total nucleotide length among all transposable elements in A. fumigatus. Deleting one of the most enriched Afut4977-sac1 in azole-resistant strains decreased azole resistance and downregulated its nearby gene, sac1, but it did not significantly affect the expression of genes of the ergosterol synthesis pathway. We then discovered that 5'LTR of Afut4977-sac1 had promoter activity and enhanced the adjacent sac1 gene expression. We found that sac1 is important to A. fumigatus, and the upregulated sac1 caused elevated resistance of A. fumigatus to azoles. Finally, we showed that Afut4977-sac1 has an evolution pattern similar to that of the whole genome of azole-resistant strains due to azoles; phylogenetic analysis of both the whole genome and Afut4977-sac1 suggests that the insertion of Afut4977-sac1 might have preceded the emergence of azole-resistant strains. Taking these data together, we found that the Afut4977-sac1 LTR-RT might be involved in the regulation of azole resistance of A. fumigatus by upregulating its nearby sac1 gene.

Environmental contamination with SARS-CoV-2 in COVID-19 hospitals in Wuhan, China, 2020.

Coronavirus disease 2019 (COVID-19) pandemic has caused high number of infections and deaths of healthcare workers globally. Distribution and possible transmission route of SARS-CoV-2 in hospital environment should be clarified. We herein collected 431 environmental (391 surface and 40 air) samples in the intensive care unit (ICU) and general wards (GWs) of three hospitals in Wuhan, China from February 21 to March 4, 2020, and detected SARS-CoV-2 RNA by real-time quantitative PCR. The viral positive rate in the contaminated areas was 17.8% (28/157), whereas there was no virus detected in the clean areas. Higher positive rate (22/59, 37.3%) was found in ICU than that in GWs (3/63, 4.8%). The surfaces of computer keyboards and mouse in the ICU were the most contaminated (8/10, 80.0%), followed by the ground (6/9, 66.7%) and outer glove (2/5, 40.0%). From 17 air samples in the contaminated areas, only one sample collected at a distance of around 30 cm from the patient was positive. Enhanced surface disinfection and hand hygiene effectively decontaminated the virus from the environment. This finding might help understand the transmission route and contamination risk of SARS-CoV-2 and evaluate the effectiveness of infection prevention and control measures in healthcare facilities.

Development of spike protein-based fluorescence lateral flow assay for the simultaneous detection of SARS-CoV-2 specific IgM and IgG.

The pandemic outbreak of the 2019 coronavirus disease (COVID-19), which is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is still spreading rapidly and poses a great threat to human health. As such, developing rapid and accurate immunodiagnostic methods for the identification of infected persons is needed. Here, we proposed a simple but sensitive on-site testing method based on spike protein-conjugated quantum dot (QD) nanotag-integrated lateral flow immunoassay (LFA) to simultaneously detect SARS-CoV-2-specific IgM and IgG in human serum. Advanced silica-core@dual QD-shell nanocomposites (SiO2@DQD) with superior luminescence and stability were prepared to serve as fluorescent nanotags in the LFA strip and guarantee high sensitivity and reliability of the assay. The performance of the SiO2@DQD-strip was fully optimized and confirmed by using 10 positive serum samples from COVID-19 patients and 10 negative samples from patients with other respiratory diseases. The practical clinical value of the assay was further evaluated by testing 316 serum samples (114 positive and 202 negative samples). The overall detection sensitivity and specificity reached 97.37% (111/114) and 95.54% (193/202), respectively, indicating the huge potential of our proposed method for the rapid and accurate detection of SARS-CoV-2-infected persons and asymptomatic carriers.

Persistent SARS-COV-2 RNA positivity in a patient for 92 days after disease onset: A case report.

RATIONALE: Recently, patients with COVID-19 who showed persistently positive SARS-CoV-2 nucleic acid test results despite resolved clinical symptoms have attracted a lot of attention. We report the case of a patient with mild symptoms of coronavirus disease (COVID-19), who achieved clinical recovery but showed persistently positive SARS-CoV-2 nucleic acid test results until Day 92 after disease onset. PATIENT CONCERNS: The patient is a 50-year-old man with mild symptoms of coronavirus disease (COVID-19). DIAGNOSES: COVID-19 pneumonia. INTERVENTIONS: The patient was quarantined for 105 days. Of these, inpatient quarantine lasted for 75 days. When the nucleic acid test results were negative for 3 consecutive days, the patient was discharged at Day 75 after disease onset. During this period, multiple samples were collected from the patient's body surface, the surrounding environment, and physical surfaces, but none of these tested positive for SARS-CoV-2. These samples included those from anal swabs, hands, inner surface of mask, cell phone, bed rails, floor around the bed, and toilet bowl surface. However, nucleic acid retest results on Day 80 and Day 92 after disease onset were positive for SARS-CoV-2 nucleic acids. OUTCOMES: The patient continued with quarantine and observation at home. After the test results on Days 101 and 105 after disease onset were negative, quarantine was terminated at last. LESSONS: Per our knowledge, this is the longest known time that a patient has tested positive for SARS-CoV-2 nucleic acids. No symptoms were observed during follow-up. During hospitalization, the SARS-CoV-2 nucleic acid positivity was not observed in samples from the body surface and surrounding environment, and no verified transmission event occurred during the quarantine at home. After undergoing clinical recovery a minority of patients with COVID-19 have shown long-term positive results for the presence of the SARS-CoV-2 nucleic acid. This has provided new understanding and research directions for coronavirus infection. Long-term follow-up and quarantine measures have been employed for such patients. Further studies are required to analyze potential infectivity in such patients and determine whether more effective antiviral drugs or regimens to enable these patients to completely clear viral infection should be researched.

Comprehensive RNA-Sequencing Analysis in Peripheral Blood Cells Reveals Differential Expression Signatures with Biomarker Potential for Idiopathic Membranous Nephropathy.

To date, the clinical course of idiopathic membranous nephropathy (iMN) remains unclear and lacks direct and effective diagnostic methods. To better understand the host gene expression changes involved in the iMN process and identify the potential signatures for clinical diagnosis, we performed a whole genome-wide transcriptome profile of peripheral blood cells (PBC) from patients with iMN and healthy controls (HCs). A total of 188 differentially expressed genes (DEGs) were detected in patients with iMN versus HCs. Gene ontology (GO) functional enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that these DEGs were mainly correlated with protein targeting, ion homeostasis GO terms, and ribosome and phagosome pathways. The top 10 differentially expressed protein-coding genes with >2-fold changes and high expression levels were validated using quantitative real-time PCR, and showed high consistency with the high-throughput sequencing results. HLA-C, S100A8, and FTH1 genes were selected for further validation and showed the most significant difference between the iMN and HC group, indicating that they could be used as potential clinical diagnostic biomarkers. Our results provide novel potential diagnostic signatures for iMN and have important implications for better understanding the pathogenesis of iMN.

Direct next-generation sequencing of virus-human mixed samples without pretreatment is favorable to recover virus genome.

Next-generation sequencing (NGS) enables the recovery of pathogen genomes from clinical samples without the need for culturing. Depletion of host/microbiota components (e.g., ribosomal RNA and poly-A RNA) and whole DNA/cDNA amplification are routine methods to improve recovery results. Using mixtures of human and influenza A virus (H1N1) RNA as a model, we found that background depletion and whole transcriptome amplification introduced biased distributions of read coverage over the H1N1 genome, thereby hampering genome assembly. Influenza serotyping was also affected by pretreatments. We propose that direct sequencing of noncultured samples without pretreatment is a favorable option for pathogen genome recovery applications.