Establishment of colloidal gold immunochromatography strip for rapid detection of Karen mikimotoi and its application.

In China, harmful algal blooms (HABs) are one of the most prominent ecological disasters in the coastal areas. Among the harmful algae species that cause HABs, Karen mikimotoi is a kind of algae that appear frequently. It can secrete hemolytic toxins and fish toxins such as glycolipids and unsaturated fatty, posing a significant threat to marine life. In order to establish a fast and effective detection technology for Karen mikimotoi that can be promoted and applied on site, we have developed a test strip which is based on monoclonal antibody technology and the colloidal gold immune-chromatography assay (GICA). The experimental results show that this test strip can detect different growth stages including growth, and stable and recession period of Karen mikimotoi. The detection results can be displayed within 3-15 min. It had high sensitivity and specificity, with a detection limit of 754 cells/mL. A colorimetric card was made to further determine the concentration of algae detected. What is more, we had developed a method that can be used for on-site enrichment of algae cells using a syringe to detect lower concentrations of Karen mikimotoi, with a minimum detection concentration of 100 cells/mL. Also the test strip was used for on-site testing along the coast of China. This test strip not only serves as a warning for the outbreak of red tide, but also provides a new approach for the development of rapid detection technology for red tide algae.

Machine learning models to predict in-hospital mortality in septic patients with diabetes.

Background: Sepsis is a leading cause of morbidity and mortality in hospitalized patients. Up to now, there are no well-established longitudinal networks from molecular mechanisms to clinical phenotypes in sepsis. Adding to the problem, about one of the five patients presented with diabetes. For this subgroup, management is difficult, and prognosis is difficult to evaluate. Methods: From the three databases, a total of 7,001 patients were enrolled on the basis of sepsis-3 standard and diabetes diagnosis. Input variable selection is based on the result of correlation analysis in a handpicking way, and 53 variables were left. A total of 5,727 records were collected from Medical Information Mart for Intensive Care database and randomly split into a training set and an internal validation set at a ratio of 7:3. Then, logistic regression with lasso regularization, Bayes logistic regression, decision tree, random forest, and XGBoost were conducted to build the predictive model by using training set. Then, the models were tested by the internal validation set. The data from eICU Collaborative Research Database (n = 815) and dtChina critical care database (n = 459) were used to test the model performance as the external validation set. Results: In the internal validation set, the accuracy values of logistic regression with lasso regularization, Bayes logistic regression, decision tree, random forest, and XGBoost were 0.878, 0.883, 0.865, 0.883, and 0.882, respectively. Likewise, in the external validation set 1, lasso regularization = 0.879, Bayes logistic regression = 0.877, decision tree = 0.865, random forest = 0.886, and XGBoost = 0.875. In the external validation set 2, lasso regularization = 0.715, Bayes logistic regression = 0.745, decision tree = 0.763, random forest = 0.760, and XGBoost = 0.699. Conclusion: The top three models for internal validation set were Bayes logistic regression, random forest, and XGBoost, whereas the top three models for external validation set 1 were random forest, logistic regression, and Bayes logistic regression. In addition, the top three models for the external validation set 2 were decision tree, random forest, and Bayes logistic regression. Random forest model performed well with the training and three validation sets. The most important features are age, albumin, and lactate.

Development of a test strip for rapid detection of Gymnodinium catenatum.

Harmful algal blooms (HABs) are major ecological and environmental problems in China's coastal waters and seriously threaten the stability of the marine ecosystem and human health. Gymnodinium catenatum is a toxic red tide dinoflagellate. It can produce paralytic shellfish toxins (PSP), which cause serious hazards to marine organisms, public health, and safety. In this paper, a test strip based on colloidal gold immunochromatography (GICG) was developed for the rapid detection of Gymnodinium catenatum. The experimental results showed that the test strip has good specificity and sensitivity. It not only detects the different components of Gymnodinium catenatum but also may detect algal toxins. The lowest density of Gymnodinium catenatum that can be detected by this test strip is approximately 120 cells/mL. Cross-reaction indicated that the test strip had a high specificity for Gymnodinium catenatum. This test strip provides a rapid method for in situ detection of Gymnodinium catenatum and a reference method for the monitoring of other harmful algae to serve as an early warning of upcoming red tides. It also provides a new way to prepare more detection methods for toxic algal toxins.

Rapid detection method of Skeletonema pseudocostatum and preparation of test strip.

In eutrophic waters, harmful algal blooms (HAB) are particularly prone to occur, which will affect the ecological environment and public health and safety. How to quickly detect and monitor marine microalgae is the key to preventing and managing HAB. Our innovative application of colloidal gold immunochromatography (GICG) technology to detect the dominant species in red tide, Skeletonema pseudocostatum, to monitor the outbreak of red tide. The experimental results show that the method and the prepared test strips are extremely sensitive and can specifically detect the presence of Skeletonema pseudocostatum. The approximate concentration of algae cells is judged by establishing a fitting relationship between the degree of color development and the concentration of algae cells. This test strip provides a quick and easy method for routine environmental monitoring, fishery water quality monitoring, and field testing of red tide monitoring. It effectively warns of the outbreak of red tides and also provides a new application direction for GICG technology.

A nomogram to predict in-hospital mortality for post-gastrointestinal resection surgery patients in intensive care units: A retrospective cohort study.

BACKGROUND: The global volume of gastrointestinal surgery has increased steadily. However, there is still a lack of studies focused on the risk factors for post-gastrointestinal resection surgery patients in the intensive care units. METHODS: Post gastrointestinal resection surgery patient data were collected from the Medical Information Mart for Intensive Care (MIMIC-III) database and divided into training set and validation set, then analyzed by Univariate and multiple logistic regression. RESULTS: 795 patients were finally enrolled in our cohort. Multiple logistic regression showed that age (1.029 [1.006-1.053]), temperature (0.337 [0.207-0.547]), respiratory rate (1.133 [1.053-1.218]), mean arterial pressure (1.204 [1.039-1.396]), lactate (1.288 [1.112-1.493]), BUN (1.025 [1.010-1.040]) and vasopressor use (4.777 [2.499-9.130]) were independent factors associated with in-hospital mortality. Our new predicted nomogram achieved a better accuracy than SOFA score, SAPS-Ⅱ score, APACHE-Ⅲ score, and Elixhauser score. CONCLUSION: Our nomogram model could well predict in-hospital mortality for post-GI resection surgery patients receiving intensive care.

Morphological and molecular characterization of Paraleptus chiloscyllii Yin & Zhang, 1983 (Nematoda: Physalopteridae) from the brownbanded bambooshark Chiloscyllium punctatum Müller & Henle (Elasmobranchii: Orectolobiformes).

Paraleptus (Spirurida: Physalopteridae) is a small genus of nematodes, parasitic in fishes, most species of which are inadequately described. Genetic data for these congeners have not been reported. The detailed morphology of P. chiloscyllii was studied using light and scanning electron microscopy, based on newly collected specimens from the brownbanded bambooshark C. punctatum Müller & Henle (Elasmobranchii: Orectolobiformes) in the Taiwan Strait. Some previously unreported morphological features of taxonomic significance were observed, i.e., pseudolabium with two sublateral rows of 6-7 small spines, 7-8 small spines on each lower rim between pseudolabia, deirids not distally bifurcated, vulva with remarkable protruding lip, presence of 1 pair medio-ventral precloacal papillae and 1 pair of discoid protrusions of postcloacal lip in male. The specimens described by González-Solís & Ali's (2015) as P. chiloscyllii from the Arabian carpetshark C. arabicum off Iraq are considered a new species, for which the name P. moraveci n. sp. is proposed. The genetic characterization of the partial small (18S) and large (28S) ribosomal DNA, and the partial mitochondrial cytochrome c oxidase subunit 1 (cox1) of P. chiloscyllii are provided for the first time. There was no intraspecific nucleotide divergence detected in the 18S and 28S regions among different individuals of P. chiloscyllii, but a low level of intraspecific genetic variation was found in the cox1 (0.62-0.92%). The present genetic data is very important for molecular identification, and will be valuable for further invertigantions on the population genetics and phylogeny of this group.

A nanodrug system overexpressed circRNA_0001805 alleviates nonalcoholic fatty liver disease via miR-106a-5p/miR-320a and ABCA1/CPT1 axis.

Our study aimed to explore the function of circRNA_0001805 in the pathogenesis of NAFLD and the underlying mechanism. A nanodrug system (GA-RM/GZ/PL) was constructed to overexpress circRNA_0001805 specifically in hepatocytes for the treatment of NAFLD. Fat droplet accumulation in cultured cells and mouse hepatic tissues was detected using Oil Red O or H&E staining. The relative expression of circRNAs, genes associated with lipogenesis was quantified by qRT-PCR. Interactions between circRNA_0001805 and miR-106a-5p/miR-320a, between miR-106a-5p/miR-320a and ABCA1/CPT1 were confirmed by dual-luciferase reporter assay. A novel metalorganic framework nanocarrier (GZ) was prepared from glycyrrhizic acid and zinc ions (Zn2+), and this nanocarrier was loaded with the circRNA_0001805 plasmid to construct a nanocore (GZ/PL). Then, this GZ/PL was coated with a galactose-modified RBC membrane (GA-RM) to generate GA-RM/GZ/PL. CircRNA_0001805 expression was downregulated in FFA-challenged primary hepatocytes, HFD-fed mice and NAFLD patients. Overexpressed circRNA_0001805 attenuated NAFLD development by suppressing lipid metabolism disorder and inflammation. CircRNA_0001805 targeted miR-106a-5p/miR-320a, which served as an upstream inhibitor of ABCA1/CPT1 and collaboratively regulated NAFLD progression. GA-RM/GZ/PL targeted hepatocytes, overexpressed circRNA_0001805, released glycyrrhizic acid to reduce the accumulation of lipids in the liver and played a synergistic role against NAFLD-induced lipid metabolism disorder.

Clinical characteristics of "re-positive" discharged COVID-19 pneumonia patients in Wuhan, China.

To analyze the clinical characteristics of re-positive discharged COVID-19 patients and find distinguishing markers. The demographic features, clinical symptoms, laboratory results, comorbidities, co-infections, treatments, illness severities and chest CT scan results of 267 patients were collected from 1st January to 15th February 2020. COVID-19 was diagnosed by RT-PCR. Clinical symptoms and nucleic acid test results were collected during the 14 days post-hospitalization quarantine. 30 out of 267 COVID-19 patients were detected re-positive during the post-hospitalization quarantine. Re-positive patients could not be distinguished by demographic features, clinical symptoms, laboratory results, comorbidities, co-infections, treatments, chest CT scan results or subsequent clinical symptoms. However, re-positive rate was found to be correlated to illness severity, according the Acute Physiology and Chronic Health Evaluation II (APACHE II) severity-of-disease classification system, and the confusion, urea, respiratory rate and blood pressure (CURB-65) score. Common clinical characteristics were not able to distinguish re-positive patients. However, severe and critical cases classified high according APACHE II and CURB-65 scores, were more likely to become re-positive after discharge.

Long noncoding RNA CCAT1 inhibits miR-613 to promote nonalcoholic fatty liver disease via increasing LXRα transcription.

Nonalcoholic fatty liver disease (NAFLD) is regarded as a threat to public health; however, the pathologic mechanism of NAFLD is not fully understood. We attempted to identify abnormally expressed long noncoding RNA (lncRNAs) and messenger RNA that may affect the occurrence and development of NAFLD in this study. The expression of differentially expressed lncRNAs in NAFLD was determined in oleic acid (OA)-treated L02 cells, and the functions of CCAT1 in lipid droplet formation were evaluated in vitro. Differentially expressed genes (DEGs) were analyzed by microarray analysis, and DEGs related to CCTA1 were selected and verified by weighted correlation network analysis. The dynamic effects of LXRα and CCTA1 on lipid droplet formation and predicted binding was examined. The binding between miR-631 and CCAT1 and LXRα was verified. The dynamic effects of miR-613 inhibition and CCTA1 silencing on lipid droplet formation were examined. The expression and correlations of miR-631, CCAT1, and LXRα were determined in tissue samples. As the results show, CCAT1 was induced by OA and upregulated in NAFLD clinical samples. CCAT1 silencing significantly suppressed lipid droplet accumulation in vitro. LXRα was positively correlated with CCAT1. By inhibiting miR-613, CCAT1 increased the transcription of LXRα and promoted LXRα expression. The expression of LXRα was significantly increased in NAFLD tissues and was positively correlated with CCAT1. In conclusion, CCAT1 increases LXRα transcription by serving as a competing endogenous RNA for miR-613 in an LXRE-dependent manner, thereby promoting lipid droplet formation and NAFLD. CCAT1 and LXRα might be potent targets for NAFLD treatment.

Photocatalytic Degradation of Oxytetracycline by Photosensitive Materials and Toxicological Analysis by Caenorhabditis elegans.

This study explored a facile one-step hydrothermal method of preparing a high-performance photocatalyst, namely, graphene-TiO2, for oxytetracycline (OTC) removal. The nanocomposites were characterized by Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy, UV-Vis diffuse reflectance spectroscopy and X-ray diffraction (XRD). The photocatalytic properties of different graphene loading types and various OTC initial concentrations, temperatures, and initial pH values were investigated. Results showed that the material with 10% graphene content exhibited the best performance and removal efficiency (beyond 99%) of OTC within 180 min at 35 °C and pH 5.5. The effects of different reactive oxygen species scavengers on photodegradation and the contributions were evaluated, and a possible reaction mechanism was proposed. Caenorhabditis elegans was used for toxicity testing during the entire degradation process and achieved a favorable result.

Heavy metal rich stone-processing wastewater inhibits the growth and development of plants.

Large amounts of wastewater are generated from stone processing, which are toxic and cause serious environmental and health risks. To quantify the content of stone processing wastewater and estimate its effects on plant growth, we collected water samples from sewage outfall of four stone processing factories and nearby water bodies. The concentration of potential toxic metals were much higher in the wastewater than background controls. Wastewater inhibited plant primary root elongation, lateral root formation, and growth of aerial part. Seedlings treated with the effluents were unhealthy with deep purple leaves and usually died before flowering. Chlorophyll a/b contents and chloroplast number were reduced in those abnormal mesophyll cells. Transcriptional levels were decreased for chloroplast formation genes, but increased for those participated in chloroplast degradation and catabolism. Six out of nine tested senescence-associated genes were up-regulated. Furthermore, our results show that endogenous toxic metal levels indeed increased after wastewater treatment. Altogether, these results indicated that the potential toxic metals rich wastewater had significant inhibition on plant growth and led to senescence-associated program cell death, which could be helpful for the government and enterprises to understand the environmental risks and formulate reasonable wastewater emission standards for the stone processing industry.

Lipoxin A4 receptor agonist BML-111 induces autophagy in alveolar macrophages and protects from acute lung injury by activating MAPK signaling.

BACKGROUND: Acute lung injury (ALI) is a life-threatening lung disease where alveolar macrophages (AMs) play a central role both in the early phase to initiate inflammatory responses and in the late phase to promote tissue repair. In this study, we examined whether BML-111, a lipoxin A4 receptor agonist, could alter the phenotypes of AM and thus present prophylactic benefits for ALI. METHODS: In vitro, isolated AMs were treated with lipopolysaccharide (LPS) to induce ALI. In response to BML-111 pre-treatment, apoptosis and autophagy of AMs were examined by flow cytometry, and by measuring biomarkers for each process. The potential involvement of MAPK1 and mTOR signaling pathway was analyzed. In vivo, an LPS-induced septic ALI model was established in rats and the preventative significance of BML-111 was assessed. On the cellular and molecular levels, the pro-inflammatory cytokines TNF-α and IL-6 from bronchoalveolar lavage were measured by ELISA, and the autophagy in AMs examined using Western blot. RESULTS: BML-111 inhibited apoptosis and induced autophagy of AMs in response to ALI inducer, LPS. The enhancement of autophagy was mediated through the suppression of MAPK1 and MAPK8 signaling, but independent of mTOR signaling. In vivo, BML-111 pre-treatment significantly alleviated LPS-induced ALI, which was associated with the reduction of apoptosis, the dampened production of pro-inflammatory cytokines in the lung tissue, as well as the increase of autophagy of AMs. CONCLUSIONS: This study reveals the prophylactic significance of BML-111 in ALI and the underlying mechanism: by targeting the MAPK signaling but not mTOR pathway, BML-111 stimulates autophagy in AMs, attenuates the LPS-induced cell apoptosis, and promotes the resolution of ALI.

Photocatalytic Degradation of Oxytetracycline by Ternary Mixed Catalyst and Toxicity Assessment Using Boar Sperm.

Response surface methodology was adopted to obtain ternary mixed catalysts of TiO2-loaded ZSM-5 zeolite and graphene. Oxytetracycline was used as challenged toxicant to evaluate the photocatalytic degradation efficiency of the composites. The optimal weight ratio of graphene, TiO2, and ZSM-5 was 1:8:1. The composites were characterized by ultraviolet-visible spectroscopy, X-ray diffraction, fourier transform infrared, N2 adsorption-desorption isotherms, and transmission electron microscope with an energy-dispersive spectroscopy system, etc. Synthesized samples showed high stability and strong visible-light absorption efficiency. The optimal operating conditions of oxytetracycline photocatalytic degradation were achieved over a wide range of pH and temperature. With 0.1 g/L of optimal ternary mixed composite, the photocatalytic degradation of oxytetracycline was nearly reached completion within 150 min at all treatment temperatures at pH 7. Toxicity of degraded oxytetracycline solution was assayed by a boar sperm quality model using fluorescent staining and flow cytometry. During 180 min of photocatalytic treatment, the degraded oxytetracycline solution showed increasing biotoxicity and changed the morphology and function of boar sperm, despite not killing them.

Evaluation of drug effects on Toxoplasma gondii nuclear and plastid DNA replication using real-time PCR.

Toxoplasma gondii Nicolle and Manceaux, 1908 is a unicellular protozoan that can infect a broad spectrum of organisms including humans. In addition to a nuclear genome, it also carries a circular DNA within a plastid-like organelle (apicoplast) and a linear genome within its mitochondria. The plastid organelle has been shown to be the target of various anti-parasitic drugs or antibiotics. To evaluate the effects of agents on the DNA replication of T. gondii, we tested six drugs (ciprofloxacin, acetylspiramycin, clindamycin, azithromycin, artemether, and sulfadiazine) on the parasite cultured in Hela cells. After drug treatment for 48 h, the parasite growth and DNA replication were evaluated and quantitated using TaqMan real-time quantitative PCR with oligonucleotide primers synthesized based on a gene from the apicoplast genome (ycf24, Genbank accession no. U87145) and a gene from the nuclear genome (uprt, Genbank accession no. U10246). Our results showed that ciprofloxacin was the most effective in inhibiting the replication of the plastid DNA after 48 h drug treatment, with a reduction of 22% in the copy number of the plastid DNA. Artemether was the most effective drug in suppressing the proliferation of tachyzoites. This study also demonstrates that real-time quantitative PCR is a simple and useful technique for monitoring parasite growth and DNA replication.

[Sited-directed mutagenesis of hCu, Zn-SOD gene and its expression in Synechococcus sp. PCC7942].

The Cys111 genetic code of human copper/zinc superoxide dismutase (hCu, Zn-SOD) gene in the pESOD plamid was mutated into the Ala111 code with site-directed mutagenesis, and then the plamid pESODT111 which contained groESL promoter, mutated hCu, Zn-SOD gene, rbcS-polyA terminator and reporter gene (Kanr) was constructed and transduced into Synechococcus sp. PCC7942 with homologous recombination platform. The results of PCR and DNA sequence analysis showed that the target nucleotide had been genetically integrated into genome DNA of the host cell. SDS-PAGE, Western blot and Pyrogallol autoxidation assay confirmed that the transformant strains expressed the mutated hCu, Zn-SOD protein. And the level of the mutated hCu, Zn-SOD protein reached a value of 3.61% of the total soluble protein. Furthermore, the transformants still retained 95% activities of SOD after 30 minutes at 80 degrees C environment, it indicated that the mutated hCu, Zn-SOD protein could endure higher temperature than the natural one.