结节病易误诊,据王洪武等~([1])收集国内18篇关于此病误诊的文献,误诊率高达63.2%,当然有误诊就会有误治,如孙永昌等~([2])报道26例结节病在影像学检查诊断的第一印象中拟诊结核5例,其中就有2例完成规范的抗结核治疗,为此应引起临床对本病诊治的重视。

Sarcoidosis

Book reviewFishes of the North-eastern Atlantic and the Mediterranean: Volume II. P.J.P. Whitehead, M.-L. Bauchot, J.-C. Hureau, J. Nielsen, E. Tortonese (Editors). UNESCO Press, Paris, 1986, pp. 510–1007, FF 250, Dfl 105.00, ISBN 92-3-002308-6

Silver nanoparticles (AgNPs) have been imposed as an excellent antimicrobial agent being able to combat bacteria in vitro and in vivo causing infections. The antibacterial capacity of AgNPs covers Gram-negative and Gram-positive bacteria, including multidrug resistant strains. AgNPs exhibit multiple and simultaneous mechanisms of action and in combination with antibacterial agents as organic compounds or antibiotics it has shown synergistic effect against pathogens bacteria such as Escherichia coli and Staphylococcus aureus. The characteristics of silver nanoparticles make them suitable for their application in medical and healthcare products where they may treat infections or prevent them efficiently. With the urgent need for new efficient antibacterial agents, this review aims to establish factors affecting antibacterial and cytotoxic effects of silver nanoparticles, as well as to expose the advantages of using AgNPs as new antibacterial agents in combination with antibiotic, which will reduce the dosage needed and prevent secondary effects associated to both.

https://www.mdpi.com/1422-0067/22/13/7202/pdf

Silver Nanoparticles and Their Antibacterial Applications

This paper provides a review of the latest research findings on the applications of microbial chitinases to biological control. Microorganisms producing these enzymes can inhibit the growth of many fungal diseases that pose a serious threat to global crop production. Currently, efforts are being made to discover producers of chitinolytic enzymes. The potential exists that natural biofungicides will replace chemical fungicides or will be used to supplement currently used fungicides, which would reduce the negative impact of chemicals on the environment and support the sustainable development of agriculture and forestry.

/pdf/chitinolytic-microorganisms-and-their-possible-application-5fvn9inzw8.pdf

Chitinolytic Microorganisms and Their Possible Application in Environmental Protection

Chitinases catalyze the degradation of chitin, a ubiquitous polymer generated from the cell walls of fungi, shells of crustaceans, and cuticles of insects They are gaining increasing attention in medicine, agriculture, food and drug industries, and environmental management Their roles in the degradation of chitin for the production of industrially useful products and in the control of fungal pathogens and insect pests render them attractive for such purposes However, chitinases have diverse sources, characteristics, and mechanisms of action that seem to restrain optimization procedures and render standardization techniques for enhanced practical applications complex Hence, results of laboratory trials are not usually consistent with real-life applications With the growing field of protein engineering, these complexities can be overcome by modifying or redesigning chitinases to enhance specific features required for specific applications In this review, the variations in features and mechanisms of chitinases that limit their exploitation in biotechnological applications are compiled Recent attempts to engineer chitinases for improved efficiency are also highlighted

/pdf/chitinase-diversity-limitations-and-trends-in-engineering-1gu0l0yamc.pdf

Chitinase: diversity, limitations, and trends in engineering for suitable applications

The present study reports the synergistic antibacterial activity of biosynthesized silver nanoparticles (AgNPs) with the aid of a combination of chitosan and seaweed-derived polyphenols as a green synthetic route. Under optimum synthesis conditions, the rapid color change from yellowish to dark brown and UV-visible absorption peak at 425 confirmed the initial formation of AgNPs. DLS, TEM, XRD, and EDX analyses revealed the spherical shape of pure biogenic AgNPs with a mean diameter size of 12 nm ± 1.5 nm, and a face-centered cubic crystal structure, respectively. FTIR and TGA results indicated the significant contribution of chitosan and polyphenol components into silver ions bioreduction and thermal stability of freshly formed AgNPs. Long-term colloidal stability of AgNPs was obtained after 6-month storage at room temperature. The bio-prepared AgNPs possessed a negative surface charge with a zeta potential value of - 27 mV. In contrast to naked chemical silver nanoparticles, the green Ag nanosamples demonstrated the distinct synergistic antibacterial in vitro toward all selected human pathogens presumably due to the presence of high content of biomolecules on their surface. The results show that synergy between chitosan and polyphenol results in the enhancement of bactericidal properties of biogenic AgNPs. We also highlighted the underlying mechanism involved in AgNPs formation based on nucleophile-electrophile interaction.

/pdf/synergistic-effects-of-combinatorial-chitosan-and-polyphenol-2dt1dxt6k9.pdf

Synergistic effects of combinatorial chitosan and polyphenol biomolecules on enhanced antibacterial activity of biofunctionalaized silver nanoparticles.

This contribution presents the biosynthesis, physiochemical properties, toxicity and photocatalytic activity of biogenic CeO2 NPs using, for the first time, marine oyster extract as an effective and rich source of bioreducing and capping/stabilizing agents in a one-pot recipe. CeO2 NPs formation was initially confirmed through the color change from light green to pale yellow and subsequently, their corresponding absorption peak was spectroscopically determined at 310 nm with an optical band-gap of 4.67 eV using the DR-UV technique. Further, XRD and Raman analyses indicated that nanoceria possessed face-centered cubic arrangements without any impurities, having an average crystallite size of 10 nm. TEM and SEM results revealed that biogenic CeO2 NPs was approximately spherical in shape with a median particle size of 15 ± 1 nm. The presence of various bioorganic substances on the surface of nanoparticles was deduced by FTIR and TGA results. It is found that marine-based nanoceria shows no cytotoxic effect on the normal cell, thus indicating their enhanced biocompatibility and biosafety to living organisms. Environmentally, due to energy band gap, visible light-activated CeO2 nanocatalyst revealed superior photocatalytic performance on degradation of methylene blue pollutant with removal rate of 99%. Owing to the simplicity, cost-effectiveness, and environmentally friendly nature, this novel marine biosynthetic route paves the way for prospective applications of nanoparticles in various areas.

Enhanced sunlight photocatalytic activity and biosafety of marine-driven synthesized cerium oxide nanoparticles.


 This contribution presents the biosynthesis, physiochemical properties, and biological activity of biogenic CeO2 NPs using, for the first time, marine oyster extract as an effective and rich source of bioreducing and capping/stabilizing agents in a one-pot recipe. CeO2 NPs formation was initially confirmed through the color change from light green to pale yellow and subsequently, their corresponding absorption peak was spectroscopically observed at 310 nm with an optical band-gap of 4.67 eV using the DR-UV technique. Further, XRD and Raman analyses indicated that nanoceria possessed face-centered cubic arrangements without any impurities, having an average crystallite size of 10 nm. TEM and histogram results revealed that biogenic CeO2 NPs was approximately spherical in shape with a median particle size of 15±1 nm. The presence of various bioorganic substances on the surface of nanoparticles was deduced by FTIR and TGA results. It is found that marine-based nanoceria shows no cytotoxic effect on the cell, thus indicating their enhanced biocompatibility and biosafety to living organisms. In contrast, nanoceria demonstrated as an effective bactericidal agent toward pathogens. Visible light-activated CeO2 nanocatalyst revealed rapid photodegradation of methylene blue. Owing to simplicity, cost-effectiveness, and environmentally friendly nature, this novel marine biosynthetic route paves the way for prospective applications of nanoparticles in various areas of bioscience.

/pdf/enhanced-sunlight-photocatalytic-activity-and-biosafety-of-5f8kjnjdx6.pdf

Enhanced Sunlight Photocatalytic Activity and Biosafety of Marine-Driven Synthesized Cerium Oxide Nanoparticles: A Future prospect

Chitinases have the ability of chitin digestion that constitutes a main compound of the cell wall in many of the phytopathogens such as fungi. Chitinase Chit42 from Trichoderma atroviride PTCC5220 is considered to play an important role in the biocontrol activity of this fungus against plant pathogens. Chit42 lacks a chitin binding domain (ChBD). We have produced a chimeric chitinase with stronger chitin-binding capacity by fusing to Chit42 a ChBD from Serratia marcescens Chitinase B. The fusion of ChBD improved the affinity to crystalline and colloidal chitin and also the enzyme activity of the chimeric chitinase when compared with the native Chit42. The chimeric chitinase showed higher antifungal activity toward phytopathogenic fungi.

Designing a new chitinase with more chitin binding and antifungal activity.

Benzo[a]pyrene (B[a]P) is an important contaminant whose liver biotransformation is dependent on the species, the route of exposure and the concentration. The goal of this study was to assess the interactions of oxidative DNA damage and CYP1A gene expression with the liver enzymes in Klunzinger’s mullet (Liza klunzingeri) exposed to benzo[a]pyrene. Sublethal doses of B[a]P (5, 10 and 50 mg/kg) were intraperitoneally administered to the fish for 14 days. The alterations in antioxidant enzymes’ activity (SOD, CAT, and GPX), hepatic enzymes’ activity (ALT, AST and ALP), DNA damage (measured by comet assay and cellProfiler software) and CYP1A gene expression in the fish liver were studied on the 1st, 3rd, 7th and 14th days. The determination of these parameters in the liver showed that most of these parameters significantly increased mostly in a time-dependent manner. Multiple regression analysis showed that DNA damage and CYP1A gene expression had positive correlations with the liver enzymes in this fish species intraperitoneally exposed to these concentrations. Moreover, these interactions indicated that theses parameters are sensitive biomarkers for the exposure to B[a]P in Klunzinger's mullet. However, other possible factors and B[a]P metabolites should be considered in future studies for better elucidating the biotransformation mechanisms and introducing better biomarkers of B[a]P.

Soheila Matroodi

Papers

Synergistic effects of combinatorial chitosan and polyphenol biomolecules on enhanced antibacterial activity of biofunctionalaized silver nanoparticles.

Enhanced sunlight photocatalytic activity and biosafety of marine-driven synthesized cerium oxide nanoparticles.

Enhanced Sunlight Photocatalytic Activity and Biosafety of Marine-Driven Synthesized Cerium Oxide Nanoparticles: A Future prospect

Designing a new chitinase with more chitin binding and antifungal activity.

Interactions of oxidative DNA damage and CYP1A gene expression with the liver enzymes in Klunzinger's mullet exposed to benzo[a]pyrene.