Resistance of Xanthomonas oryzae pv. oryzae to Lytic Phage X2 by Spontaneous Mutation of Lipopolysaccharide Synthesis-Related Glycosyltransferase

Phage therapy is a promising biocontrol management on plant diseases caused by bacterial pathogens due to its specificity, efficiency and environmental friendliness. The emergence of natural phage-resistant bacteria hinders the application of phage therapy. Xanthomonas oryzae pv. oryzae (Xoo) is the causal agent of the devastating bacterial leaf blight disease of rice. Here, we obtained a spontaneous mutant C2R of an Xoo strain C2 showing strong resistance to the lytic phage X2. Analysis of the C2R genome found that the CDS2289 gene encoding glycosyltransferase acquired a frameshift mutation at the 180th nucleotide site, which also leads to a premature stop mutation at the 142nd amino acid. This mutation confers the inhibition of phage adsorption through the changes in lipopolysaccharide production and structure and bacterial surface morphology. Interestingly, glycosyltransferase-deficient C2R and an insertional mutant k2289 also showed reduced virulence, suggesting the trade-off costs of phage resistance. In summary, this study highlights the role of glycosyltransferase in interactions among pathogenic bacteria, phages and plant hosts, which provide insights into balanced coevolution from environmental perspectives.     

The role of electrochemical biosensors in SARS-CoV-2 detection: a bibliometrics-based analysis and review

The global pandemic of COVID-19, which began in late 2019, has resulted in extremely high morbidity and severe mortality worldwide, with important implications for human health, international trade, and national politics. Severe acute respiratory syndrome coronavirus (SARS-CoV-2) is the primary pathogen causing COVID-19. Analytical chemistry played an important role in this global epidemic event, and detection of SARS-CoV-2 even became a part of daily life. Analytical chemists have devoted much effort and enthusiasm to this event, and different analytical techniques have shown very rapid development. Electrochemical biosensors are highly efficient, sensitive, and cost-effective and have been used to detect many highly pathogenic viruses long before this event. However, another fact is that electrochemical biosensors are not the technology of choice for most detection applications. This review describes for the first time the role played by electrochemical biosensors in SARS-CoV-2 detection from a bibliometric perspective. This paper analyzed 254 relevant research papers up to June 2022. The contributions of different countries and institutions to this topic were analyzed. Keyword analysis was used to explore different methodological attempts of electrochemical detection techniques. More importantly, we are trying to find an answer to the question: do electrochemical biosensors have the potential to become a genuinely employable detection technology in an outbreak of infectious disease?

This review describes for the first time the role played by electrochemical biosensors in SARS-CoV-2 detection from a bibliometric perspective.     

Optimized Formulation of Magnetic Chitosan Microspheres Containing the Anticancer Agent,Oxantrazole

A combined emulsion/polymer cross-linking/solvent evaporation technique was used to prepare magnetic chitosan microspheres (MCM) containing the anticancer drug, oxantrazole. A central composite experimental design was used to simultaneously evaluate a variety of formulation factors on a number of response variables, such as the percentage of oxantrazole entrapped in the MCM. In association with the study design, statistical optimization procedures indicated the factors that significantly influence MCM preparation and what levels of the factors are needed to produce optimum MCM. Entrapment of anticancer agents into biodegradable microspheres is difficult because of low aqueous drug solubility and porosity of the particles. The latter effect was circumvented by a chitosan cross-linking step that resulted in 3% (w/w) oxantrazole entrapment in the MCM via the optimization procedures. The combined formulation and statistical optimization strategy provide a basis to develop other microparticulate systems and led to a dosage form that can be used for future in vivo investigations.     

A Comparative Study to Evaluate the Essential Work of Fracture to Measure the Fracture Toughness of Quasi-Brittle Material

In the present work, three different woven composite laminates were fabricated using the hand lay-up method. The woven reinforcement fibres were carbon fibres (CFRP), glass fibres (GFRP-W) and (GFRP-R) in combination with epoxy resin. Then, the central notch specimen tensile test (CNT) was used to measure the fracture toughness and the corresponding surface release energy (GIC). Then, the data were compared with the essential work of fracture (we) values based on the stored energy of the body to obtain a new standard fracture toughness test for composite laminates using relatively simple techniques. In addition to an extended finite element model, XFEM was implemented over a central notch specimen geometry to obtain a satisfactory validation of the essential work of fracture concepts. Therefore, the average values of (GIC) were measured with CNT specimens 25.15 kJ/m², 32.5 kJ/m² and 20.22 kJ/m² for CFRP, GFRP-W and GFRP-R, respectively. The data are very close as the percentage error for the surface release energy measured by the two methods was 0.83, 4.6 and 5.16 for carbon, glass and random fibre composite laminates, respectively. The data for the fracture toughness of XFEM are also very close. The percentage error is 4.6, 5.25 and 2.95 for carbon, glass and random fibre composite laminates, respectively. Therefore, the fundamental work of the fracture concept is highly recommended as a fracture toughness test for composite laminates or quasi-brittle Material.     

Electronic blood glucose monitoring impacts on provider and patient behavior

ObjectiveRecent technological development along with the constraints imposed by the coronavirus disease 2019 (COVID-19) pandemic have led to increased availability of patient-generated health data. However, it is not well understood how to effectively integrate this new technology into large health systems. This article seeks to identify interventions to increase utilization of electronic blood glucose monitoring for patients with diabetes.Materials and MethodsA large randomized controlled trial tested the impact of multiple interventions to promote use of electronic blood glucose tracking. The total study sample consisted of 7052 patients with diabetes across 68 providers at 20 selected primary care offices. The design included 2 stages: First, primary care practices were randomly assigned to have their providers receive education regarding blood glucose flowsheet orders. Then, patients in the treated practices were assigned to 1 of 4 reminder interventions.ResultsProvider education successfully increased provider take-up of an online blood glucose monitoring tool by 64 percentage points, while a comparison of reminder interventions revealed that emphasizing accountability to the provider encouraged patients to track their blood glucose online. An assessment of downstream outcomes revealed impacts of the interventions on prescribing behavior and A1c testing frequency.DiscussionIt is important to understand how health systems can practically promote take-up and awareness of emerging digital health alternatives or those with persistently low utilization in clinical settings.ConclusionThese results indicate that provider training and support are critical first steps to promote utilization of patient-generated health data, and that patient communications can provide further motivation.     

Metabolic and pharmacological profiling of Penicillium claviforme by a combination of experimental and bioinformatic approaches

BackgroundPenicillium produces a wide range of structurally diverse metabolites with significant pharmacological impacts in medicine and agriculture. For the first time, a complete metabolome of Penicillium claviforme (P. claviforme) (FBP-DNA-1205) was studied alongside pharmacological research in this study.MethodsThe metabolic profile of P. claviforme fermented on Potato Dextrose Broth (PDB) was investigated in this work. The complete metabolomics studies of fungus were performed using GC-MS and LC-MS-QTOF techniques. An in vitro model was utilised to study the cytotoxic and antioxidant activities, while an in vivo model was employed to investigate the antinociceptive and acute toxicity activities. Molecular Operating Environment (MOE) software was used for molecular docking analysis.ResultsGC-MS study showed the presence of alkanes, fatty acids, esters, azo and alcoholic compounds. Maculosin, obtain, phalluside, quinoline, 4,4’-diaminostilbene, funaltrexamine, amobarbital, and fraxetin were among the secondary metabolites identified using the LC-MS-QTOF technique. The n-hexane fraction of P. claviforme displayed significant cytotoxic activity in vitro, with an LD50 value of 92.22 µgml⁻¹. The antinociceptive effects in vivo were dose-dependent significantly (p < .001). Interestingly, during the 72 h of investigation, no acute toxicity was demonstrated. In addition, a docking study of tentatively identified metabolites against the inflammatory enzyme (COX-2) supported the antinociceptive effect in an in silico model.ConclusionMetabolic profile of P. claviforme shows the presence of biologically relevant compounds in ethyl acetate extract. In addition, P. claviforme exhibits substantial antioxidant and cytotoxic activities in an in vitro model as well as antinociceptive activity in an in vivo model. The antinociceptive action is also supported by a molecular docking study. This research has opened up new possibilities in the disciplines of mycology, agriculture, and pharmaceutics.

Key messages

• The first time explored complete metabolome through GC-MS and LC-MS-QTOF.
• Both in vivo & in vitro pharmacological investigation of P. claviforme.
• In silico molecular docking of LC-MS-QTOF metabolites.