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Bacterial infection poses severe threats to public health, and early rapid detection of the pathogen is critical for controlling bacterial infectious diseases. Current methods are commonly labor intensive, time consuming or dependent on lab-based equipment. In this study, we proposed a novel and practical method for bacterial detection based on smartphones using the surface plasmon resonance (SPR) phenomena of gold nanoparticles (AuNPs). The proposed smartphone-based SPR sensing method is achieved by utilizing color development that arises from the change in interparticle distance of AuNPs induced by bacterial lysate. The pictures of bacteria/AuNPs color development were captured, and their color signals were acquired through a commercial smartphone. The proposed method has a detection range between 2.44 × 10

Massive pulmonary embolism (PE) is a life-threatening complication of major surgery with a mortality rate of up to 50%. Extracorporeal membrane oxygenation (ECMO) is primarily used for respiratory and circulatory support. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) was used to stabilize patients with acute massive PE. Acute brain injury, vascular disease, and immunosuppression, as proposed in the 2021 ELSO guidelines, are contraindications to ECMO. We report a case of a patient with craniocerebral trauma whose postoperative course was complicated by massive PE and subsequent cardiac arrest that required emergent VA‐ECMO, followed by anticoagulation with heparin. The patient showed hemodynamic improvement. The patient was discharged 68 days after hospitalization.

Background: MCE is a safe and effective myocardial perfusion assessment technique; it is used for the assessment of post MI viability. Case presentation: A 52-year-old male with cardiogenic shock caused by secondary acute myocardial infarction and successful coronary stent implantation with ECMO, IABP and ventilator assistance and with no significant recovery of postoperative cardiac function. The result of MCE was also reported. The allograft was successfully performed 8 days after ECMO-assisted support. The patient was successfully transferred to the general ward 8 days after surgery and successfully discharged on day 86 of admission. Conclusions: ECMO provides effective mechanical assistance support for patients with end-stage heart failure, buys time for heart transplantation surgery, and was an effective cardiopulmonary support treatment. An evaluation of myocardial perfusion and survival quantity was an important reference for emergency heart transplantation.

Humic substances (HS) can facilitate electron transfer during biogeochemical processes due to their redox properties, but the structure-redox activity relationships are still difficult to describe and poorly understood. Herein, the linear (Partial Least Squares regressions; PLS) and nonlinear (artificial neural network; ANN) models were applied to monitor the structure dependence of HS redox activities in terms of electron accepting (EAC), electron donating (EDC) and overall electron transfer capacities (ETC) using its physicochemical features as input variables. The PLS model exhibited a moderate ability with R

Although Bcl-xL has been shown to retrotranslocate Bax from mitochondria to cytosol, other studies have found that Bcl-xL also stabilizes the mitochondrial localization of Bax. It is still unclear what causes the difference in Bcl-xL-regulated Bax localization. Bad, a BH3-only protein with a high affinity for Bcl-xL, may play an important role in Bcl-xL-regulated Bax shuttling. Here, we found that Bcl-xL enhanced both translocalization and retrotranslocation of mitochondrial Bax, as evidenced by quantitative co-localization, western blots and fluorescence loss in photobleaching (FLIP) analyses. Notably, Bad knockdown prevented Bcl-xL-mediated Bax retrotranslocation, indicating Bad was essential for this process. Quantitative fluorescence resonance energy transfer (FRET) imaging in living cells and co-immunoprecipitation analyses showed that the interaction of Bcl-xL with Bad was stronger than that with Bax. The Bad mimetic ABT-737 dissociated Bax from Bcl-xL on isolated mitochondria, suggesting that mitochondrial Bax was directly liberated to cytosol due to Bad binding to Bcl-xL. In addition, MK-2206, an Akt inhibitor, decreased Bad phosphorylation while increasing cytosolic Bax proportion. Our data firmly demonstrate a notion that Bad binds to mitochondrial Bcl-xL to release Bax, resulting in retrotranslocation of Bax to cytosol, and that the amount of Bad involved is regulated by Akt signaling.

BACKGROUND Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2, is a worldwide pandemic. Some COVID-19 patients develop severe acute respiratory distress syndrome and progress to respiratory failure. In such cases, extracorporeal membrane oxygenation (ECMO) treatment is a necessary life-saving procedure. CASE SUMMARY Two special COVID-19 cases—one full-term pregnant woman and one elderly (72-year-old) man—were treated by veno-venous (VV)-ECMO in the Second People’s Hospital of Zhongshan, Zhongshan City, Guangdong Province, China. Both patients had developed refractory hypoxemia shortly after hospital admission, despite conventional support, and were therefore managed by VV-ECMO. Although both experienced multiple ECMO-related complications on top of the COVID-19 disease, their conditions improved gradually. Both patients were weaned successfully from the ECMO therapy. At the time of writing of this report, the woman has recovered completely and been discharged from hospital to home; the man remains on mechanical ventilation, due to respiratory muscle weakness and suspected lung fibrosis. As ECMO itself is associated with various complications, it is very important to understand and treat these complications to achieve optimal outcome. CONCLUSION VV-ECMO can provide sufficient gas exchange for COVID-19 patients with acute respiratory distress syndrome. However, it is crucial to understand and treat ECMO-related complications.

Background: Lower limb ischemia in patients with extracorporeal membrane oxygenation (ECMO) via femoral artery catheterization negatively affects patient mortality and survivors’ quality of life [Gulkarov 2020]. In this study, ECMO was established via femoral artery catheterization. This study aimed to identify the risk factors of lower limb ischemia to provide sufficient evidence for its prevention. Methods: All patients with venoarterial (VA) ECMO via femoral artery catheterization in Zhongshan People’s Hospital from January 2008 to November 2019 retrospectively were analyzed. Patients’ general information and ECMO-related information were obtained, and the main outcome variables were survival and discharge and intubation-related adverse events (limb ischemia and incision bleeding). Logistic regression analysis was used to determine the independent risk factors of limb ischemia in patients with VA ECMO. Results: A total of 179 (98 [54.7%] men and 81 [45.3%] women) eligible patients were included in this study. Moreover, a total of 90 patients (48.9%) had low cardiac output, 41 (22.3%) had acute myocardial infarction, and 33 (17.9%) had fulminant myocarditis. Eighty-six (48.04%) patients survived to hospital discharge, 36 (20.11%) had limb ischemia, and 42 (23.46%) had incision bleeding. Furthermore, the ECMO-assisted time was 114.23 ± 67.88 hours. There was no significant difference in age, sex, and Sequential Organ Failure Assessment score between the limb ischemia group and the non-limb ischemia group. Multivariate logistic regression analysis showed that peripheral artery disease (odds ratio, 27.12; 95% confidence interval, 5.614–130.96) was an independent risk factor of limb ischemia in patients with ECMO. Conclusion: Limb ischemia is a common complication in patients with VA ECMO, and peripheral artery disease is an independent risk factor of limb ischemia in patients with VA ECMO via femoral artery catheterization.

Background: Using tourniquets in the lower extremities can increase the incidence of deep vein thrombosis (DVT). Acute large-area pulmonary embolism (APE) occurs in severe cases, and it is fatal to most patients. Acute large-area pulmonary embolism causes haemodynamic instability, right heart failure, and circulatory failure. Case presentation: A 47-year-old female patient was subjected to spinal anaesthesia for a comminuted fracture of the tibia and fibula of the left lower limb. After the tourniquet was released during the operation, she had sudden hypotension and lost consciousness. Thus, ECMO was used to support patient circulation. With ECMO-assisted CT examination, she was diagnosed to have a pulmonary embolism. On the next day, she was subjected to a bilateral pulmonary embolism and embolectomy. Lastly, she was transferred to the general ward and discharged smoothly. Conclusions: Patients undergoing fracture surgery should be wary of APE caused by the loss of DVT after the release of tourniquets. ECMO, as a rapid and effective temporary life support intervention, provides effective cardiopulmonary support and new treatment plans. It also saves time for further treatment of patients with high-risk APE.

Pneumonia caused by coronavirus disease 2019 (COVID-19) is a highly contagious disease. Unfortunately, research on extracorporeal membrane oxygenation (ECMO) assisted treatments for patients with COVID-19 infection is limited. In this case study, a patient who was in late pregnancy (35+2 weeks of pregnancy) and suffering from severe COVID-19 was extremely irritable during ECMO-assisted treatment after she underwent a cesarean section. Her Richmond Agitation Sedation Scale (RASS) score reached +3. Nevertheless, the patient successfully was treated with a continuous single/combined application of propofol, midazolam, dexmedetomidine, hibernation mixture, and other drugs for several days (maintaining RASS -2 to -4) and provided with anti-infection, mechanical ventilation, nutritional support, fluid balance under hemodynamic monitoring, liver support, and other organ function support treatments. ECMO-assisted sedation strategy for patients was introduced and discussed in this case to provide a certain reference for the clinical diagnosis and treatment of such patients.

Rapid measurement of waterborne bacterial viability is crucial for ensuring the safety of public health. Herein, we proposed a colorimetric assay for rapid measurement of waterborne bacterial viability based on a difunctional gold nanoprobe (dGNP). This versatile dGNP is composed of bacteria recognizing parts and signal indicating parts, and can generate color signals while recognizing bacterial suspensions of different viabilities. This dGNP-based colorimetric assay has a fast response and can be accomplished within 10 min. Moreover, the proposed colorimetric method is able to measure bacterial viability between 0% and 100%. The method can also measure the viability of other bacteria including

Artesunate (ARS) induced significant reactive oxygen species (ROS) generation in HepG2, HeLa, and A549 lines. However, ARS induced ROS-dependent apoptosis in HeLa and A549 cell lines but ROS-independent apoptosis in HepG2 cells. A total of 200 μM hydrogen peroxide (H(2)O(2)) significantly induced cytotoxicity in HeLa cells, while H(2)O(2) up to 300 μM did not induce cytotoxicity in HepG2 cells, further demonstrating the strong resistance of HepG2 cells to ROS. HeLa cells had much higher basic total glutathione (T-GSH) level than HepG2 cells, while the ratio of basic reduced glutathione (GSH)/oxidized glutathione (GSSG) in HepG2 cells was nearly twice than that in HeLa and A549 cells. Inhibition of glutathione markedly enhanced H(2)O(2)- or ARS-induced cytotoxicity in HeLa and A549 cell lines but modestly enhanced the cytotoxicity of H(2)O(2) and even did not affect the cytotoxicity of ARS in HepG2 cells. Moreover, addition of GSH remarkably prevented H(2)O(2)- or ARS-induced cytotoxicity in HeLa and A549 cell lines, further indicating the involvement of GSH in scavenging ROS in the two cell lines. HepG2 cells exhibited higher catalase activity than HeLa cells, and inhibiting catalase activity by using 3-aminotriazole (3-AT, a specific inhibition of catalase) or catalase siRNA remarkably reduced the resistance of HepG2 cells to ROS, demonstrating the key roles of catalase for the strong resistance of HepG2 cells to ROS. Collectively, catalase activity instead of glutathione level dominates the resistance of cells to ROS.

The “trash to treasure” process has been extensively demonstrated for various energy and environmental issues in the past few decades. Abundant biomass is well accepted as a carbon-rich, sustainable, and renewable precursor, offering us a plethora of possibilities for advanced materials for energy conversion and storage as well as environmental treatments; spatial modification of biomass facilitates the formation of a unique three-dimensional (3D) structure with micro- to macropores, yielding higher surface area and enhanced physicochemical properties. This novel concept provides sufficient reaction sites, excellent adsorption capability, more activated sites for catalyst doping, and fascinating electrochemical performance. Basically, the 3D cadre of biomass-derived carbon strengthens the economic competitiveness of these materials and broadens their applications in fields such as in supercapacitors, chemical batteries, bioenergy harvest, adsorbents for organic pollutants and greenhouse gases, and efficient (photo)catalysts. The scope of this review mainly focuses on the most popular synthesis methodology of three-dimensional carbon materials derived from biomass and their critical applications in the fields of energy and environment.

Introduction: Patients with coronavirus disease (COVID-19) may develop acute respiratory distress syndrome (ARDS). There have been few reports of postpartum woman with ARDS secondary to COVID-19 who required respiratory support using veno-venous extracorporeal membrane oxygenation (ECMO). We present the case of a 31-year-old woman who was admitted to hospital at 35 weeks gestation with ARDS secondary to COVID-19 and required ECMO during the postpartum period. Patient concerns: The patient had obvious dyspnea, accompanied by chills and fever. Her dyspnea worsened and her arterial oxygen saturation decreased rapidly. Diagnosis: ARDS secondary to COVID-19. Interventions: Emergency bedside cesarean section. Medications included immunotherapy (thymosin α 1), antivirals (lopinavir/ritonavir and ribavirin), antibiotics (imipenem-cilastatin sodium and vancomycin), and methylprednisolone. Ventilatory support was provided using invasive mechanical ventilation. This was replaced by venous-venous ECMO 5 days postpartum. ECMO management focused on blood volume control, coagulation function adjustment, and airway management. Outcomes: The patient was successfully weaned for ECMO and the ventilator and made a good recovery. Conclusion: Special care, including blood volume control, coagulation function adjustment, and airway management, should be provided to postpartum patients with ARDS secondary to COVID-19 who require ECMO support.

Accurate traffic prediction is an indispensable work for urban traffic planning, traffic control and traffic management. But it is quite challenging to model the complex spatiotemporal correlation of the traffic data. To tackle this problem, we propose a Spatial-Temporal Dilated and Graph Convolutional Network(STDGCN) where first order approximation graph convolution is employed to capture the spatial correlations and dilated convolution is selected to extract the temporal one. Besides, the periodicity of traffic data is considered by multiple components. Extensive experiments on two real-world traffic datasets show our model obtains a competitive performance on traffic flow prediction task.

Binding of Bcl-XL to Beclin-1 reduces Beclin-1's capacity to induce autophagy. This report aims to explore whether this interaction affects Bcl-XL's anti-apoptotic function. Using fluorescence resonance energy transfer (FRET) two-hybrid assay to quantify the stoichiometry of Bcl-XL-Beclin-1 complex in living cells coexpressing Bcl-XL-CFP and Beclin-1-YFP, we showed that Bcl-XL bond to Beclin-1 to form hetero-oligomers whose stoichiometry increases from 1:1 to 2:1 or higher with the increasing relative expression level of Bcl-XL, indicating the multiple binding sites of Beclin-1 with Bcl-XL. Co-expression of Bcl-XL and Beclin-1 exhibited consistent anti-apoptotic ability against staurosporine (STS)-induced apoptosis with expression of Bcl-XL alone irrespective of the relative expression level between Beclin-1 and Bcl-XL. Collectively, Bcl-XL complexed with Beclin-1 maintains full anti-apoptotic ability independent of the stoichiometry of Bcl-XL-Beclin-1 complex.

An enzyme-free biosensor for the amplified detection of aflatoxin B1 has been constructed based on a catalytic DNA circuit. Three biotinylated hairpin DNA probes (H1, H2, and H3) were designed as the assembly components to construct the sensing system (triplex H1-H2-H3 product). Cascaded signal amplification capability was obtained through toehold-mediated strand displacement reactions to open the hairpins and recycle the trigger DNA. By the use of streptavidin-functionalized gold nanoparticles as the signal indicators, the colorimetric readout can be observed by the naked eye. In the presence of a target, the individual nanoparticles (red) aggregate into a cross-linked network of nanoparticles (blue) via biotin-streptavidin coupling. The colorimetric assay is ultrasensitive, enabling the visual detection of trace levels of aflatoxin B1 (AFB1) as low as 10 pM without instrumentation. The calculated limit of detection (LOD) is 2 pM in terms of 3 times standard deviation over the blank response. The sensor is robust and works even when challenged with complex sample matrices such as rice samples. Our sensing platform is simple and convenient in operation, requiring only the mixing of several solutions at room temperature to achieve visible and intuitive results, and holds great promise for the point-of-use monitoring of AFB1 in environmental and food samples.

With the complexity of the video environment and the problem of possible noise during data transmission, traditional robust principal component analysis (RPCA) failed to obtain the lowest rank representation from corrupted data. A method of video denoising and an object detection algorithm based on the RPCA model with total variation and rank-1 constraint (TVR1-RPCA) is proposed; it employs the more refined prior representations for the static and dynamic components of the video sequences. The proposed method is based on RPCA under the framework of low-rank sparse decomposition; the rank-1 constraint is exploited to describe the strong low-rank property of the background layer, TV regularization is combined with l1 regularization to constrain the sparsity and spatial continuity of the foreground component, and l2 norm regularization is combined to constrain the noise to make up for the deficiencies of the existing RPCA model. In addition, an efficient algorithm based on the alternating direction method of multipliers is designed to solve the proposed video denoising and moving object detection issues. Our experiments on static and moving camera videos demonstrate that the proposed method is superior to the state-of-the-art methods in terms of denoising capability and detection accuracy.

Objectives Solithromycin is a new monotherapy option for community-acquired bacterial pneumonia (CABP) patients. However, the efficacy and safety of solithromycin monotherapy for the treatment of CABP remains controversial. The aim of this meta-analysis was to evaluate the role that solithromycin played in the treatment of CABP. Methods We systematically retrieved randomised controlled trials (RCTs) compared solithromycin with other antibiotics in the treatment of CABP, which were published on PubMed, ScienceDirect, Cochrane libary and the Clinical Trials.gov before July 2018. Ultimately, a meta-analysis of all RCTs eligible for inclusion criteria was performed. Results Three RCTs, comprising 1855 patients, were included in the meta-analysis. There were no statistically significant differences between patients given solithromycin and those given other antibiotics with regard to early clinical response (ECR) [1855 patients, odds ratio (OR) = 1.00, 95% confidence interval (CI) 0.80 to 1.24, P = 0.99] and clinical success rates at short-term follow-up (SFU) (1855 patients, OR = 0.78, 95% CI 0.60 to 1.01, P = 0.06) in the intention-to-treat (ITT) population, as were the ECR (787 patients, OR = 0.90, 95% CI 0.64 to 1.27, P = 0.55) and clinical success rates at SFU (358 patients, OR = 0.73, 95% CI 0.41 to 1.31, P = 0.30) in microbiological intention-to-treat population (mITT). Similarly, with regard to the occurrence of treatment-emergent adverse events (TEAEs), drug-related adverse events (AEs), serious AEs, serious drug-related AEs and mortality, no statistically significant difference between patients given solithromycin and those given other antibiotics was observed. Conclusion In the treatment of CABP, solithromycin monotherapy is an effective and safe antibiotic regimen. Other advantages (ie anti-inflammatory effect, potent activity against expected pathogens of CABP and convenient clinical use) of solithromycin may make it a more fascinating option compared with the currently used regimens.

The ability of Geobacter species to transfer electrons outside cells enables them to play an important role in biogeochemical and bioenergy processes. Our knowledge of the extracellular electron transfer (EET) process in the genus Geobacter is mainly from the study of G. sulfurreducens, and in order to fully investigate the EET mechanisms in the genus Geobacter, other Geobacter species should also be considered. This study focused on the EET of Geobacter soli GSS01, which exhibited a capability of reducing insoluble Fe(III) oxides and generating electrical current comparable with G. sulfurreducens PCA. Electrochemical characterization, including cyclic voltammetry, differential pulse voltammetry, and electrochemical in situ FTIR spectra, revealed that different redox proteins contributed to the electrochemical behaviors of G. soli and G. sulfurreducens. Based on comparative transcriptomic and proteomic analyses, OmcS was the most upregulated protein in both G. soli and G. sulfurreducens cells grown with insoluble Fe(III) oxides vs. soluble electron acceptor. However, the proteins including OmcE and PilA that were previously reported as being important for EET in G. sulfurreducens were downregulated or unchanged in G. soli cells grown with insoluble electron acceptors vs. soluble electron acceptor, and many proteins that were upregulated in G. soli cells grown with insoluble electron acceptors vs. soluble electron acceptor, such as OmcN, are not important for EET in G. sulfurreducens. We also identified 30 differentially expressed small RNAs (sRNAs) in G. soli cells grown with different acceptors. Taken together, these findings help to understand the versatile EET mechanisms that exist in the genus Geobacter and point to the possibility of sRNA in modulating EET gene expression.

C-type cytochromes (c-cyts) facilitate microbial extracellular electron transfer and play critical roles in biogeochemical cycling, bioelectricity generation and bioremediation. In this study, a simple and effective method has been developed to detect microbial c-cyts by means of peroxidase mimetic reaction on screen-printed carbon electrode (SPCE). To this end, bacteria cells were immobilized onto the working electrode surface of SPCE by a simple drop casting. After introducing 3,3′,5,5′-tetramethylbenzidine (TMB) solution, microbial c-cyts with peroxidase-like activity catalyze the oxidation of TMB in the presence of hydrogen peroxide. The oxidized TMB was electrochemically determined and the current signal was employed to calculate the c-cyts content. This electrochemical method is highly sensitive for microbial c-cyts with a low detection limit of 40.78 fmol and a wide detection range between 51.70 fmol and 6.64 pmol. Moreover, the proposed technique can be universally expanded to detect c-cyts in other bacteria species such as Fontibacter ferrireducens, Pseudomonas aeruginosa, Comamonas guangdongensis and Escherichia coli. Furthermore, the proposed method confers an in situ facile and quantitative c-cyts detection without any destructive sample preparations, complex electrode modifications and expensive enzyme- or metal particle- based signal amplification. The suggested method advances an intelligent strategy for in situ quantification of microbial c-cyts and consequently holds promising application potential in microbiology and environmental science.

Microbial extracellular respiration (MER) involves the transfer of electrons to extracellular substrates and has significant environmental implications. Conventional methods for MER ability determination are reagent- and time-consuming, have a low throughput, or require noncommercial instruments. In this study, a plate-based colorimetric assay is proposed to measure MER ability. This method utilizes the peroxidase activity of the key components (multi-heme c-type cytochromes) of the extracellular electron-transfer network. The bacterial intrinsic peroxidase-catalyzed oxidation of chromogen (e.g., tetramethylbenzidine) resulted in a measurable color change correlated with the MER ability of the tested microorganisms. The results of the proposed colorimetric assay correspond well with those of traditional methods, such as the dissimilatory Fe(III) reduction method (Spearman’s ρ of 0.946; P < 0.01) and the electricity generation method (Spearman’s ρ of 0.893; P < 0.01). The proposed method allows researchers...

Extracellular respiring bacteria (ERB) are a group of bacteria capable of transferring electrons to extracellular acceptors and have important application in environmental remediation. In this study, a decomposable quantum-dots (QDs)/DNA nanosphere probe was developed for rapid and ultrasensitive detection of ERB. The QDs/DNA nanosphere was self-assembled from QDs-streptavidin conjugate (QDs-SA) and Y-shaped DNA nanostructure that is constructed based on toehold-mediated strand displacement. It can release numerous fluorescent QDs-SA in immunomagnetic separation (IMS)-based immunoassay via simple biotin displacement, which remarkably amplifies the signal of antigen-antibody recognizing event. This QDs/DNA-nanosphere-based IMS-fluorescent immunoassay is ultrasensitive for model ERB Shewanella oneidensis, showing a wide detection range between 1.0 cfu/mL and 1.0 × 108 cfu/mL with a low detection limit of 1.37 cfu/mL. Moreover, the proposed IMS-fluorescent immunoassay exhibits high specificity, acceptable reproducibility and stability. Furthermore, the proposed method shows acceptable recovery (92.4–101.4%) for detection of S. oneidensis spiked in river water samples. The proposed IMS-fluorescent immunoassay advances an intelligent strategy for rapid and ultrasensitive quantitation of low-abundance analyte and thus holds promising potential in food, medical and environmental applications.

Concatenated logic circuits operating as a biocomputing keypad-lock security system with an automatic reset function have been successfully constructed on the basis of toehold-mediated strand displacement and three-way-DNA-junction architecture. In comparison with previously reported keypad locks, the distinctive advantage of the proposed security system is that it can be reset and cycled spontaneously a large number of times without an external stimulus, thus making practical applications possible. By the use of a split-G-quadruplex DNAzyme as the signal reporter, the output of the keypad lock can be recognized readily by the naked eye. The "lock" is opened only when the inputs are introduced in an exact order. This requirement provides defense against illegal invasion to protect information at the molecular scale.

The genus Shewanella is ubiquitous in environment and has been extensively studied for their applications in bioremediation. A novel immunoassay for ultrasensitive detection of Shewanella oneidensis was presented based on graphene oxide (GO) as nanogold carrier with silver enhancement strategy. The enhanced sensitivity was achieved by employing conjugate-featuring gold nanoparticles (AuNPs) and antibodies (Ab) assembled on bovine serum albumin (BSA)-modified GO (Ab/AuNPs/BSA/GO). After a sandwich-type antigen-antibody reaction, Ab/AuNPs/BSA/GO conjugate binding on the target analyte produced an enhanced immune-recognition response by the reduction of silver ion in the present of hydroquinone. The deposited silver metal was dissolved with nitric acid and subsequently quantified by anodic stripping voltammetry. The high AuNPs loading capacity of GO and the obvious signal amplification by gold-catalyzed silver deposition offer an excellent detection method with a wide range of linear relationship between 7.0 × 10(1) and 7.0 × 10(7)cfu/mL. Furthermore, the immunoassay developed in this work exhibited high sensitivity, acceptable stability and reproducibility. This simple and sensitive assay method has promising application in various fields for rapid detection of bacteria, protein and DNA.

Dissolved organic carbons in biochar (BDOM), obtained from thermal treatment (i.e., pyrolysis) of biomass, is of great importance due to their excellent redox properties and capacity to remove contaminants from the aqueous and soil environment. However, little is known about the intimate relationship between redox activity of BDOM and pyrolysis temperatures of the biomass. In this study, BDOMs were extracted from wheat straw biochar at different temperatures (from 300 °C to 700 °C). The physicochemical analyses indicated that the quinone and aromatic moieties in BDOM increased with the increase in pyrolysis temperature up to 500 °C, and then decreased as the temperature continued to rise. The results of electrochemical analysis revealed that the electron transfer capability (ETC) reached a maximum for the BDOM-500 with an electron donor capability (EDC) of 0.14 mmole- (g C)−1 and electron accepting capability (EAC) of 0.31 mmole- (g C)−1, which were both significantly higher than that of other as-prepared BDOMs. The EAC and EDC of BDOM samples both followed the order BDOM-500 > BDOM-400 > BDOM-600 > BDOM-300 > BDOM-700, demonstrating that the quinone and aromatic groups highly contributed to the redox activity of the BDOM. For Cr(VI) removal, the highest removal efficiency (~77%) was achieved in the presence of BDOM-500 and lactate as an electron donor, which was consistent with the profiles of ETC. These findings present a guidance for the optimization of BDOM that efficiently mediates pollutants removal for environmental remediation.

Triphenyl phosphate (TPHP) is one of the major organophosphate esters (OPEs) with increasing consumption. Considering its largely distribution and high toxicity in aquatic environment, it is important to explore an efficient treatment for TPHP. This study aimed to investigate the accelerated degradation of TPHP in a three-electrode single chamber bioelectrochemical system (BES). Significant increase of degradation efficiency of TPHP in the BES was observed compared with open circuit and abiotic controls. The one-order degradation rates of TPHP (1.5 mg L−1) were increased with elevating sodium acetate concentrations and showed the highest value (0.054 ± 0.010 h−1) in 1.0 g L−1 of sodium acetate. This result indicated bacterial metabolism of TPHP was enhanced by the application of micro-electrical field and addition acetate as co-substrates. TPHP could be degraded into diphenyl phosphate (DPHP), hydroxyl triphenyl phosphate (OH-TPHP) and three byproducts. DPHP was the most accumulated degradation product in BES, which accounted more than 35.5% of the initial TPHP. The composition of bacterial community in BES electrode was affected by the acclimation by TPHP, with the most dominant bacteria of Azospirillum, Petrimonas, Pseudomonas and Geobacter at the genera level. Moreover, it was found that the acute toxic effect of TPHP to Vibrio fischeri was largely removed after the treatment, which revealed that BES is a promising technology to remove TPHP threaten in aquatic environment.

A Gram-negative, straight to slightly curved rod-shaped bacterium, motile with peritrichous flagella, designated SgZ-6T, was isolated from an electroactive biofilm and was characterized by means of a polyphasic approach. Growth occurred with 0–5.0 % (w/v) NaCl (optimum 1 %), at pH 6.0–10.0 (optimum pH 7.0) and at 10–42 °C (optimum 30 °C) in trypticase soya broth. Phylogenetic analyses based on the 16S rRNA and gyrB genes identified the isolate as a member of a novel species of the genus Pseudomonas . Strain SgZ-6T exhibited the highest 16S rRNA gene sequence similarity to ‘ Pseudomonas linyingensis’ CGMCC 1.10701 (97.5 %), followed by Pseudomonas sagittaria JCM 18195T (97.4 %), P. oleovorans subsp. lubricantis DSM 21016T (96.6 %), P. tuomuerensis JCM 14085T (96.5 %) and P. alcaliphila JCM 10630T (96.4 %). Strain SgZ-6T showed the highest gyrB gene sequence similarity of 93.7 % to ‘P. linyingensis’ CGMCC 1.10701 among all type strains of genus Pseudomonas . DNA–DNA pairing studies showed that strain SgZ-6T displayed 47.1 and 40.3 % relatedness to ‘P. linyingensis’ CGMCC 1.10701 and P. sagittaria JCM 18195T, respectively. The major isoprenoid quinone was ubiquinone 9 (Q-9). The whole-cell fatty acids consisted mainly of summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c). The DNA G+C content of the genomic DNA was 68.1 mol%. On the basis of phenotypic, chemotaxonomic and phylogenetic data, strain SgZ-6T is proposed to represent a novel species of the genus Pseudomonas , for which the name Pseudomonas guangdongensis sp. nov. is proposed. The type strain is SgZ-6T ( = CCTCC AB 2012022T = KACC 16606T). An emended description of the genus Pseudomonas is also proposed.

An ultrasensitive and high-throughput nucleic acid detection system, termed as strand displacement reaction-enzyme linked immunosorbent assay (SDR-ELISA), has been developed on the basis of antibody-like DNA nanostructures. Three digoxigenin or biotin modified hairpin probes are utilized to construct antibody-like DNA nanostructures that feature affinity toward streptavidin and anti-digoxigenin antibody via isothermal target-triggered SDR amplification. These antibody-like nanostructures have been employed to conjugate horseradish-peroxidase-labeled anti-digoxigenin antibody with streptavidin that is immobilized on microliter plate wells for enzyme-linked colorimetric assay. The resulting SDR-ELISA system is ultrasensitive for target DNA with a low detection limit of 5 fM. Moreover, the SDR-ELISA system is capable of discriminating DNA sequences with single base mutations, and do so in a high-throughput manner by detection and quantification of up to 96 or 384 DNA samples in a single shot. This detection system is further applied to detect other DNA targets such as Shewanella oneidensis specific DNA sequence, which indicates the generality of proposed SDR-ELISA system. The integration of SDR amplification and convenient ELISA technique advances an intelligent strategy for ultrasensitive and high-throughput nucleic acid detection, which may be amenable for direct visual detection and quantification using an accompanying quantitative color chart.

The detection of nucleic acid sequences is of great importance in a variety of fields. An ultrasensitive DNA sensing platform is constructed using elaborately designed diblock hairpin probes (DHPs) that are composed of hairpin and poly-adenine blocks. The introduction of an initiator DNA target triggers the catalytic assembly of probes DHP1, DHP2 and DHP3 to fabricate numerous poly-adenine-tailed branched DNA junctions, which significantly amplify the signal of the target-DNA-recognizing event without any enzyme. Coupled to a gold nanoparticle-based colorimetric assay, the amplified recognition signal can be quantitatively detected or visually read with the naked eye. The combination of the high-efficiency target-catalyzed DHP assembly and sensitive gold-based colorimetric assay offers an ultrasensitive detection of DNA with a detection limit of 0.1 pM and a dynamic range from 0.01 to 5 pM. The proposed sensing platform can discriminate even single-base mutations. Moreover, the sensing platform can be expanded to detect pollutant-degrading-bacteria-specific DNA sequences. The proposed sensing system should offer an alternative approach for the detection of nucleic acids in the fields of microbiology, biogeochemistry, and environmental sciences.

Two novel Gram-staining-positive, rod-shaped, endospore-forming and moderately thermophilic bacteria, designated strains DX-3T and GIESS002, were isolated from sludge composts from Guangdong Province, China. Analysis of 16S rRNA gene sequences revealed that the isolates were closely related to each other with extremely high similarity (99.6 %), and were members of the family Bacillaceae . However, these two isolates formed a novel phylogenetic branch within this family. Their closest relatives were the members of the genera Ornithinibacillus , Oceanobacillus and Virgibacillus . Cells of both strains were facultatively anaerobic and catalase- and oxidase-positive. The cell-wall peptidoglycan type was A1γ (meso-diaminopimelic acid direct). The predominant isoprenoid quinone was MK-7. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine. The major cellular fatty acid was iso-C15 : 0. The DNA G+C content was 43.2–43.7 mol%. The results of a polyphasic taxonomic study indicated that strains DX-3T and GIESS002 represent a novel species in a new genus in the family Bacillaceae , order Bacillales , for which the name Compostibacillus humi gen. nov., sp. nov. is proposed. The type strain is DX-3T ( = KCTC 33104T = CGMCC 1.12360T).

This study aimed to assess the in vivo efficacy of acid sensing ion channel 3 (ASIC3) inhibitor APETx2 to alleviate acute gastric mucosal lesion (AGML) in a rat model. Thirty-six male Wistar rats were divided randomly into three groups: control group, water immersion restraint stress (WIRS) group, and APETx2 treatment group (n = 12). AGML was induced by WIRS for 6 h, and 25 microg/kg APETx2 was injected intraperitoneally before the onset of stress. Intragastric pH, ulcer index (UI) and gastric histopathological changes were measured, ASIC3 expression in thoracic dorsal root ganglia (DRG) neurons was examined by immunohistochemistry, PCR and Western blot analysis. Compared with control group, WIRS group showed obvious gastric injury with increased UI score, decreased intragastric pH and increased ASIC3 expression in DRG neurons (p0.05). APETx2 treatment before WIRS significantly alleviated gastric mucosal injury, decreased UI score, decreased gastric acidity and reduced ASIC3 expression in thoracic DRG neurons (p0.05). In conclusion, ASIC3 expression in DRG neurons projecting to the stomach is positively correlated with gastric mucosal lesion and acidosis in WIRS model. ASIC3 inhibitor APETx2 could improve gastric acidosis and alleviate AGML.