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We investigate thermal emission from n-doped GaAs/AlGaAs quantum wells (QWs). Emission peaks with Lorentzian shapes (linewidth 11~19 meV) that reflect transitions between the first and second conduction subbands are observed in the mid-infrared range. It is demonstrated that the emission characteristics can be tuned by modifying the QW parameters. The peak emissivity is increased from 0.3 to 0.9 by modifying the doping density, and the peak wavelength is tuned from 6 to 10 μm by changing the well width. The obtained results are useful for the design of narrow-band thermal emitters. [ABSTRACT FROM AUTHOR]

The article discusses a study which characterized bacteriophage pAh-1 and its effects on experimental infection of Aeromonas hydrophila (A. hydrophila) in Zebrafish ( Danio rerio). Topics include the successful isolation of the new lytic phage using stream water and the experimental infection as an indicator strain, the limited lytic activity showed by the pAh-1 against the three Aeromonas strains, and the growth profile of A. hydrophila after pAh-1 infection.

Discovering natural carotenoids for colour enhancement and health benefits of fish is important to develop new feed formulations. We have purified natural bixin from achiote seeds and evaluated the effect of colour enhancing and pigmentation in goldfish. Varying levels of bixin-based diets were prepared with 420 g kg−1 of crude protein and 120 g kg−1 of lipid content. Our results clearly showed that bixin (0.05, 0.10, 0.20 and 0.60 g kg−1) based diets significantly ( P < 0.05) enhanced the skin and fin colour at 30 and 60 days compared to diet without bixin. Interestingly, diet which contains 0.20 g kg−1 bixin and commercial feed (with astaxanthin) had similar effect on carotenoid deposition in skin. Moreover, total carotenoid deposition in fin was higher than in skin of all bixin-containing diets. However, 0.60 g kg−1 bixin-containing diet had lower specific growth rate (1.01 ± 0.01) and higher feed conversion ratio (2.05 ± 0.19) compared to the control group. The present results demonstrate that achiote bixin can be successfully used as an alternative natural carotenoid source against synthetic astaxanthin in fish feed. Our data indicate that 0.20 g kg−1 is a suitable dietary level of bixin to ensure strong pigmentation, acceptable growth and feed utilization in goldfish. [ABSTRACT FROM AUTHOR]

Fusarium oxysporum species complex (FOSC) is a highly diverse fungus. Recently, F. oxysporum infection was identified from zebrafish ( Danio rerio) culturing system in Korea. Initially, a rapid whitish smudge was appeared in the water with the fungal blooming on walls of fish tanks. Microscopic studies were conducted on fungal hyphae, colony pigmentation and chlamydospore formation and the presence of macro- and microspores confirmed that the isolated fungus as F. oxysporum. Furthermore, isolated F. oxysporum was confirmed by internal transcribed spacer sequencing which matched (100%) to nine F. oxysporum sequences available in GenBank. Experimental hypodermic injection of F. oxysporum into adult zebrafish showed the development of fungal mycelium and pathogenicity similar to signs observed. Histopathologic results revealed a presence of F. oxysporum hyphae in zebrafish muscle. Fusarium oxysporum growth was increased with sea salt in a concentration-dependent manner. Antifungal susceptibility results revealed that F. oxysporum is resistant to copper sulphate (up to 200 μg mL−1) and sensitive to nystatin (up to 40 μg mL−1). This is the first report of FOSC from zebrafish culture system, suggesting it appears as an emerging pathogen, thus posing a significant risk on zebrafish facilities in the world. [ABSTRACT FROM AUTHOR]

Aim: Mutations in K-ras codon 12 and 13 of exon 2 are known to affect prognosis and impart resistance to anti-epidermal growth factor monoclonal antibody therapy in colorectal carcinoma (CRC). Our aim was to investigate the utility value of modified mismatch polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay to detect mutation in K-ras codons of CRC patients and to relate the mutational status to liver metastasis.Methodology: Mismatch PCR-RFLP was developed to detect K-ras mutations in DNA isolated from paraffinized tumor tissue of thirty CRC patients. All patients had 5 year follow-up data to detect liver metastasis. Cross-tabulations were generated between K-ras mutations and the metastatic status. The Chi-square test was used to indicate statistical significance of the association.Results: Of the 30 CRC patients investigated, K-ras mutations of codons 12 and/or 13 of exon 2 were detected in 14 (46.6%). Meanwhile, 13 patients (43.3%) were observed to have developed liver metastases. There was a significant association between the presence of the K-ras mutation in codon 12 and the occurrence of liver metastasis (χ2 = 4.693, P = 0.030) on the contrary to the mutation in codon 13 to which such occurrence of liver metastases was not seen (χ2 = 1.884, P = 0.169).Conclusion: Codon 12 of exon 2 of K--ras gene detected by modified mismatch PCR-RFLP assay is significantly associated with liver metastasis in CRC patients during the first 5 years after surgery. Thus, modified mismatch PCR-RFLP protocol is a suitable method in this setting to detect K-ras gene mutations predicting liver metastasis in CRC patients. [ABSTRACT FROM AUTHOR]

Pet turtles are considered a source of bacterial infection to humans when handled in captivity. Turtles purchased from 9 pet shops and 8 online markets in Korea were examined to determine whether the turtles and their environment were contaminated with Citrobacter spp. bacteria. Biochemical tests and morphology revealed that Citrobacter spp. were isolated from 7 fecal and 76 environmental samples. Among the 7 fecal isolates, 5 bacteria were identified as Citrobacter freundii through 16SrRNA gene sequencing. The isolation rate of Citrobacter spp. from soil and water samples increased over time. Each of the isolate's antibiotic resistance was characterized with a disk diffusion test. The strains showed susceptibility against amikacin, ceftriaxone, ciprofloxacin, imipenem, sulfamethoxazole/trimethoprim, and tetracycline, but were resistant to cefoxitin, cephalotin, and chloramphenicol. These results indicate that pet turtles are a potential source of Citrobacter infection in humans in Korea. [ABSTRACT FROM AUTHOR]

Bacterial extracellular vesicles (BEVs) are natural nanocarriers that have shown great potential for biomedical applications such as biomarkers, cancer therapy, immunomodulators, vaccines, wound healing, tissue engineering, and drug carriers. In the present study, BEVs were isolated from the gram-negative bacterium, Aeromonas hydrophila using the ultracentrifugation method and denoted as AhEVs. Using transmission electron microscopy imaging, we confirmed the ultrastructure and spherical shape morphology of AhEVs. Nanoparticle-tracking analysis results showed a mean particle size of 105.5 ± 2.0 nm for AhEVs. Moreover, the particle concentration of AhEVs was 2.34 ± 0.12 × 10 11 particles/mL of bacterial supernatant. AhEV-treated fathead minnow (FHM) cells did not show cytotoxicity effects up to 50 μg/mL with no significant decrease in cells. Moreover, no mortality was observed in larval zebrafish up to 50 μg/mL which indicates that the AhEVs are biocompatible at this concentration. Furthermore, fluorescent-labeled AhEVs were internalized into FHM cells. Results of qRT-PCR analysis in FHM cells revealed that cellular pro-inflammatory cytokines such as nuclear factor (NF)-κB, interferon (Ifn), Irf7, interleukin (Il) 8, and Il11 were upregulated while downregulating the expression of anti-inflammatory Il10 in a concentration-dependent manner. AhEV-treated adult zebrafish (5 μg/fish) induced toll-like receptor (tlr) 2 and tlr4; tumor necrosis factor-alpha (tnfα); heat shock protein (hsp) 70; and il10, il6, and il1β in kidney. Protein expression of NF-κB p65 and Tnfα presented amplified levels in the spleen of AhEVs-treated zebrafish. Based on the collective findings, we conclude that AhEVs exhibited morphological and physicochemical characteristics to known EVs of gram (-)ve bacteria. At biocompatible concentrations, the immunomodulatory activity of AhEVs was demonstrated by inducing different immune response genes in FHM cells and zebrafish. Hence, we suggest that AhEVs could be a novel vaccine candidate in fish medicine due to their ability to elicit strong immune responses., Competing Interests: Declaration of competing interest The authors declared that no conflicts of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Candida auris, an emerging multidrug-resistant fungal pathogen discovered in Japan in 2009, poses a significant global health threat, with infections reported in about 25 countries. The escalation of drug-resistant strains underscores the urgent need for new treatment options. This study aimed to investigate the antifungal potential of 2,3,4,4a-tetrahydro-1H-xanthen-1-one (XA1) against C. auris, as well as its mechanism of action and toxic profile. The antifungal activity of XA1 was first evaluated by determining the minimum inhibitory concentration (MIC), time-kill kinetics and biofilm inhibition. In addition, structural changes, membrane permeability, reactive oxygen species (ROS) production, and in vitro and in vivo toxicity of C. auris after exposure to XA1 were investigated. The results indicated that XA1 exhibited an MIC of 50 μg/mL against C. auris, with time-kill kinetics highlighting its efficacy. Field emission scanning electron microscopy (FE-SEM) showed structural damage in XA1-treated cells, supported by increased membrane permeability leading to cell death. Furthermore, XA1 induced ROS production and significantly inhibited biofilm formation. Importantly, XA1 exhibited low cytotoxicity in human epidermal keratinocytes (HaCaT), with a cell viability of over 90 % at 6.25 μg/mL. In addition, an LD 50 of 17.68 μg/mL was determined in zebrafish embryos 24 h post fertilization (hpf), with developmental delay observed at prolonged exposure at 6.25 μg/mL (48-96 hpf). These findings position XA1 as a promising candidate for further research and development of an effective antifungal agent., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Multidrug-resistant Streptococcus parauberis causes high fish mortality in aquaculture, necessitating an urgent need for innovative control strategies. This study aimed to develop an immunizing agent against S. parauberis using exosomes isolated from the plasma of olive flounders infected experimentally with S. parauberis (Sp-Exo). Initially, we tested the in vitro immunomodulatory effect of Sp-Exo in murine macrophage RAW264.7 cells and compared it to that of exosomes isolated from naïve fish (PBS-Exo-treated). Notably, Sp-Exo treatment significantly (p < 0.05) upregulated pro-and anti-inflammatory cytokines (Il1β, Tnfα, and Il10), antimicrobial peptide, defensin isoforms (Def-rs2 and Def-ps1), and antiviral (Ifnβ1 and Isg15) genes. In vivo studies in larval and adult zebrafish revealed similar patterns of immunomodulation. Furthermore, larval and adult zebrafish exhibited significantly (p < 0.05) enhanced resistance to S. parauberis infection following treatment with Sp-Exo compared to that with PBS-Exo. Proteomic analysis using isobaric tags for relative and absolute quantitation (iTRAQ) approach revealed the presence of 77 upregulated and 94 downregulated differentially expressed proteins (DEPs) in Sp-Exo, with 22 and 37 significantly (p < 0.05) upregulated and downregulated DEPs, respectively. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes, and Search Tool for the Retrieval of Interacting Genes/Proteins analyses revealed that these genes are associated with key pathways, such as innate immune responses, complement system, acute phase responses, phospholipid efflux, and chylomicron remodeling. In conclusion, Sp-Exo demonstrated superior immunomodulatory activity and significant resistance against S. parauberis infection relative to that on treatment with PBS-Exo. Proteomic analysis further verified that most DEPs in Sp-Exo were associated with immune induction or modulation. These findings highlight the potential of Sp-Exo as a promising vaccine candidate against S. parauberis and other bacterial infections in olive flounder., Competing Interests: Declaration of competing interest The authors declared that no conflicts of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Bacterial extracellular vesicles (BEVs) are nanosized structures that play a role in intercellular communication and transport of bioactive molecules. Streptococcus parauberis is a Gram-positive pathogenic bacterium that causes "Streptococcosis" in fish. In this study, we isolated S. parauberis-derived extracellular vesicles (SpEVs), and then physicochemical and immunomodulatory properties were determined to elucidate their biological functions. Initially, the biogenesis of SpEVs was detected using field emission scanning electron microscopy, which revealed that secretory phase SpEVs attached to the outer surface of S. parauberis. SpEVs had an average particle diameter and zeta potential of 168.3 ± 6.5 nm and -17.96 ± 2.11 mV, respectively. Field emission transmission electron microscopy analysis confirmed the presence of round or oval-shaped SpEVs with clear membrane margins. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis results showed three sharp protein bands when SpEVs were stained with Coomassie blue. In vitro toxicity of SpEVs was assayed using the murine macrophage RAW 264.7 cells and we observed no significant (p < 0.05) viability reduction up to 50 μg/mL qRT-PCR results revealed that SpEVs-treated (5 and 10 μg/mL) RAW 264.7 cells significantly (p < 0.05) induced the mRNA of proinflammatory (Il1β, Il6, and Tnfα) and anti-inflammatory (Il10) cytokines in a concentration-dependent manner. In vivo immunomodulatory effects of SpEVs were investigated by injecting SpEVs (5 and 10 μg/fish) into adult zebrafish. Transcriptional analysis based on qRT-PCR indicates significant (p < 0.05) upregulation of proinflammatory (il1β, il6, and tnfα) and anti-inflammatory (il10) genes in a concentration-dependent manner in zebrafish kidney. Further, protein expression results in zebrafish spleen tissue confirmed the immunomodulatory activity of SpEVs. In conclusion, SpEVs display the characteristics of BEVs and immunomodulatory activities, suggesting their potential application as vaccine candidate., Competing Interests: Declaration of competing interest The authors declared that no conflicts of interest., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Under the increasing threat to native ecosystems posed by non-native species invasions, there is an urgent need for decision support tools that can more effectively identify non-native species likely to become invasive. As part of the screening (first step) component in non-native species risk analysis, decision support tools have been developed for aquatic and terrestrial organisms. Amongst these tools is the Weed Risk Assessment (WRA) for screening non-native plants. The WRA has provided the foundations for developing the first-generation WRA-type Invasiveness Screening Kit (ISK) tools applicable to a range of aquatic species, and more recently for the second-generation ISK tools applicable to all aquatic organisms (including plants) and terrestrial animals. Given the most extensive usage of the latter toolkits, this study describes the development and application of the Terrestrial Plant Species Invasiveness Screening Kit (TPS-ISK). As a second-generation ISK tool, the TPS-ISK is a multilingual turnkey application that provides several advantages relative to the WRA: (i) compliance with the minimum standards against which a protocol should be evaluated for invasion process and management approaches; (ii) enhanced questionnaire comprehensiveness including a climate change component; (iii) provision of a level of confidence; (iv) error-free computation of risk scores; (v) multilingual support; (vi) possibility for across-study comparisons of screening outcomes; (vii) a powerful graphical user interface; (viii) seamless software deployment and accessibility with improved data exchange. The TPS-ISK successfully risk-ranked five representative sample species for the main taxonomic groups supported by the tool and ten angiosperms previously screened with the WRA for Turkey. The almost 20-year continuous development and evolution of the ISK tools, as opposed to the WRA, closely meet the increasing demand by scientists and decision-makers for a reliable, comprehensive, updatable and easily deployable decision support tool. For terrestrial plant screening, these requirements are therefore met by the newly developed TPS-ISK., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Viral haemorrhagic septicaemia virus (VHSV) is one of the highly pathogenic virus, which causes viral haemorrhagic septicaemia disease in both marine and freshwater fish. Micro RNA-155 (miRNA-155) is a multifunctional small non-coding RNA and it involves regulation of immune responses during viral infection. In this study, dre-miR-155 mimics were encapsulated into chitosan nanoparticles (CNPs). Resulted encapsulated product (miR-155-CNPs) was investigated for its immunomodulation role in zebrafish during experimentally challenged VHSV infection. Successful encapsulation of dre-miR-155 mimics into CNPs was confirmed through average nanoparticle (NPs) size (341.45 ± 10.00 nm), increased encapsulation efficiency percentage (98.80%), bound dre-miR-155 with chitosan, sustained release in vitro (up to 40%), and the integrity of RNA. Overexpressed miR-155 was observed in gills, muscle, and kidney tissues (5.42, 19.62, and 140.72-folds, respectively) after intraperitoneal delivery of miR-155-CNPs into zebrafish upon VHSV infection (miR-155-CNPs + VHSV). The miR-155-CNPs + VHSV infected fish had the highest cumulative survival (85%), which was associated with low viral copy numbers. The miR-155-overexpressing fish showed significantly decreased expression of ifnγ, irf2bpl, irf9, socs1a, il10, and caspase3, compared to that of the miR-155 inhibitor + VHSV infected fish group. In contrast, il1β, tnfα, il6, cd8a, and p53 expressions were upregulated in miR-155-overexpressed zebrafish compared to that of the control. The overall findings indicate the successful delivery of dre-miR-155 through miR-155-CNPs that enabled restriction of VHSV infection in zebrafish presumably by modulating immune gene expression., Competing Interests: Declaration of competing interest The authors declared that no conflicts of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Polydeoxyribonucleotide (PDRN) is an accelerated diabetic wound healing therapy with promising abilities to promote cell growth, angiogenesis, collagen synthesis, and reduce inflammation where its sustainable delivery and release behavior is critical to ensure effective wound healing properties. Therefore, a nanopolyplex was developed here, by encapsulating PDRN with chitosan to affirm its delivery systematically. The physicochemical characterization revealed its successful encapsulation which facilitates the gradual release of PDRN. In vitro studies of the polyplex demonstrated no cytotoxicity and enhanced cell proliferation and migration properties with high antimicrobial activities. In vivo, wound healing studies in Wistar rats dorsal skin defect model induced with diabetes mellitus affirm the highest wound healing activity and wound closure rate by chitosan/PDRN polyplex treatment. Considerably high histopathological changes such as epithelialization, collagen deposition, blood vessels, and hair follicle formation were observed under the polyplex treatment. The immunohistochemical analysis for platelet endothelial cell adhesion molecule (CD31) and cluster of differentiation (CD68) revealed the ability of polyplex to increase CD31 expression and decrease CD68 expression thereby promoting the wound healing process. Collectively, these results suggest that significantly accelerated, high-quality wound healing effects could be obtained by the developed chitosan/PDRN polyplex and thus it could be introduced as a potential therapeutic product for diabetic wound healing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Antimicrobial peptides (AMPs) are considered a novel approach to stimulate fish antiviral mechanisms for defense against a broad range of viral infections by enhancing immunomodulatory activities. Octominin is an AMP derived from the defense proteins of Octopus minor. In this study, preliminary screening of octominin against viral hemorrhagic septicemia virus (VHSV), infectious hematopoietic necrosis virus (IHNV), and infectious pancreatic necrosis virus (IPNV) was carried out. Moreover, immune responses upon octominin treatment and IHNV challenge were investigated using fathead minnow (FHM) cells. The CC 50 s of octominin for FHM and Chinook salmon embryo-214 (CHSE-214) cells were 2146.2 and 1865.2 μg/mL, respectively. With octominin treatment, EC 50 resulted in 732.8, 435.1, and 925.9 μg/mL for VHSV, IHNV, and IPNV, respectively. The selectivity indices were 2.9, 4.9, and 2.0, respectively. The transcriptional analysis results demonstrated the induced transcription factors (Irf3; 143-fold, Irf7; 105-fold, and NF-κB; 8-fold), stress response gene (HspB8; 2-fold), and apoptosis functional gene (p53; 3-fold) in octominin treated (500 μg/mL) FHM cells for 48 h. Moreover, IHNV viral copy number was slightly decreased with the octominin treatment (500 μg/mL) in FHM cells. Overall results suggest that octominin could be a potential antiviral agent, although further studies are necessary to understand its mode of action and the mechanism of its antiviral activity., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Most clinically isolated Candida albicans strains are drug-resistant, emphasizing the urgent need to discover alternative therapies. In this study, the previously characterized Octominin was modified into a shorter peptide with an 18 amino acid sequence ( 1 GWLIRGAIHAGKAIHGLI 18 ) and named Octominin II. The secondary structure of Octominin II is a random coil with a helical turn and a positive charge (+2.46) with a hydrophobic ratio of 0.46. Octominin II inhibited C. albicans , C. auris , and C. glabrata with minimum inhibitory and fungicidal concentrations against C. albicans of 80 and 120 µg/mL, respectively. Field emission scanning electron microscopy confirmed that Octominin II treatment caused ultra-structural changes in C. albicans cells. Furthermore, membrane permeability results for the fluorescent indicator propidium iodide revealed modifications in cell wall integrity in Octominin II-treated C. albicans . Octominin II treatment increases the production of reactive oxygen species (ROS) in C. albicans . Gene expression studies revealed that Octominin II suppresses virulence genes of C. albicans such as CDR1 , TUP1 , AGE3 , GSC1 , SAP2 , and SAP9 . In addition, a nucleic acid binding assay revealed that Octominin II degraded genomic DNA and total RNA in a concentration-dependent manner. Additionally, Octominin II inhibited and eradicated C. albicans biofilm formation. Octominin II showed relatively less cytotoxicity on raw 264.7 cells (0-200 µg/mL) and hemolysis activity on murine erythrocytes (6.25-100 µg/mL). In vivo studies confirmed that Octominin II reduced the pathogenicity of C. albicans . Overall, the data suggests that Octominin II inhibits C. albicans by employing different modes of action and can be a promising candidate for controlling multidrug-resistant Candida infections.

Klebsiella variicola strain was identified from a natural water stream. Novel phage (KPP-1) infecting K. variicola was isolated and characterized. The biocontrol efficacy of KPP-1 against K. variicola-infected adult zebrafish was also investigated. The host K. variicola strain was resistant to six of the antibiotics tested and comprised the virulence genes kfuBC, fim, ureA, and Wza-Wzb-Wzc cps . Morphological analysis by transmission electron microscopy revealed that KPP-1 has icosahedron head and tail structures. The latent period and burst size of KPP-1 were 20 min and 88 PFU per infected cell, respectively, at a multiplicity of infection of 0.1. KPP-1 was stable over a broad pH range (3-11), temperature (4-50 °C), and salinity (0.1-3%). KPP-1 inhibits the growth of K. variicola in vitro and in vivo. In the zebrafish infection model, treatment with KPP-1-infected K. variicola demonstrated 56% of cumulative survival. This suggests the possibility of developing KPP-1 as a potential biocontrol agent against multidrug-resistant K. variicola that belongs to the K. pneumoniae complex., (© 2023. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

This study investigated the antiviral activity of aqueous leaf extract of Costus speciosus (TB100) against influenza A. Pretreatment of TB100 in RAW264.7 cells enhanced antiviral activity in an assay using the green fluorescence-expressing influenza A/Puerto Rico/8/1934 (H1N1) virus. The fifty percent effective concentration (EC50) and fifty percent cytotoxic concentration (CC50) were determined to be 15.19 ± 0.61 and 117.12 ± 18.31 µg/mL, respectively, for RAW264.7 cells. Based on fluorescent microscopy, green fluorescence protein (GFP) expression and viral copy number reduction confirmed that TB100 inhibited viral replication in murine RAW264.7 and human A549 and HEp2 cells. In vitro pretreatment with TB100 induced the phosphorylation of transcriptional activators TBK1, IRF3, STAT1, IKB-α, and p65 associated with interferon pathways, indicating the activation of antiviral defenses. The safety and protective efficacy of TB100 were assessed in BALB/c mice as an oral treatment and the results confirmed that it was safe and effective against influenza A/Puerto Rico/8/1934 (H1N1), A/Philippines/2/2008 (H3N2), and A/Chicken/Korea/116/2004 (H9N2). High-performance liquid chromatography of aqueous extracts led to the identification of cinnamic, caffeic, and chlorogenic acids as potential chemicals for antiviral responses. Further confirmatory studies using these acids revealed that each of them confers significant antiviral effects against influenza when used as pretreatment and enhances the antiviral response in a time-dependent manner. These findings suggest that TB100 has the potential to be developed into an antiviral agent that is effective against seasonal influenza.

Exosomes are a group of extracellular vesicles carrying membrane proteins, lipids, RNAs, and, cytosolic proteins, which play key role in intercellular communication and homeostasis. This study describes the isolation, physicochemical, morphological and molecular characterization, toxicity, wound healing, and regeneration properties of plasma derived exosomes from naive (phosphate-buffered saline [PBS]-injected; PBS-Exo) and Streptococcus parauberis-challenged (Sp-Exo) olive flounder (Paralichthys olivaceus). The average diameters of PBS-Exo and Sp-Exo were 120.5 ± 6.1 and 113.1 ± 9.3 nm, respectively, and they presented unique cup shape morphologies. Both exosomes exhibited classical tetraspanin surface markers (CD81, CD9, and CD63) and were enriched with acetylcholinesterase. High-throughput miRNA profiling revealed differentially expressed miRNAs (log 2 fold change ≥1; P < 0.05), including 14 known and 22 novel miRNAs, in Sp-Exo. Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that the target genes of the miRNAs contribute towards various physiological and immunological functions, including wound healing and fin regeneration. Sp-Exo exhibited a rapid wound healing (cell migration) capacity in human fibroblast cells, and its mRNA and protein expression patterns corroborated its activity. Higher larval fin regeneration was more prevalent in Sp-Exo than in PBS-Exo, which further confirmed its functional significance. Our study provides the first basic physiochemical, morphometric, molecular (miRNA profiling), and wound healing evidences of Sp-Exo in olive flounder and highlights important miRNA cargoes in exosomes that may be potential therapeutic candidates in wound healing., Competing Interests: Declaration of competing interest The authors declared that no conflicts of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Realizing large-scale single-mode, high-power, high-beam-quality semiconductor lasers, which rival (or even replace) bulky gas and solid-state lasers, is one of the ultimate goals of photonics and laser physics. Conventional high-power semiconductor lasers, however, inevitably suffer from poor beam quality owing to the onset of many-mode oscillation 1,2 , and, moreover, the oscillation is destabilized by disruptive thermal effects under continuous-wave (CW) operation 3,4 . Here, we surmount these challenges by developing large-scale photonic-crystal surface-emitting lasers with controlled Hermitian and non-Hermitian couplings inside the photonic crystal and a pre-installed spatial distribution of the lattice constant, which maintains these couplings even under CW conditions. A CW output power exceeding 50 W with purely single-mode oscillation and an exceptionally narrow beam divergence of 0.05° has been achieved for photonic-crystal surface-emitting lasers with a large resonant diameter of 3 mm, corresponding to over 10,000 wavelengths in the material. The brightness, a figure of merit encapsulating both output power and beam quality, reaches 1 GW cm -2  sr -1 , which rivals those of existing bulky lasers. Our work is an important milestone toward the advent of single-mode 1-kW-class semiconductor lasers, which are expected to replace conventional, bulkier lasers in the near future., (© 2023. The Author(s).)

Acinetobacter baumannii is an opportunistic bacterial pathogen that causes severe infections in immunocompromised individuals. A. baumannii forms biofilm and produces extracellular matrix, which supports bacteria to survive under harsh conditions and be resistant to antibacterial treatments. In the present study, we investigated the biofilm and quorum-sensing inhibitory effects of antimicrobial peptide, octopromycin in A. baumannii . Field emission-scanning electron microscopy results clearly showed significantly reduced biofilm mass and caused a collapse in biofilm architecture at the minimum inhibitory concentration (50 µg/mL) and minimum bactericidal concentration (200 µg/mL) of octopromycin. Antibiotic-resistant persister cells of A. baumannii were successfully killed by octopromycin treatment, and it inhibited violacein production in Chromobacterium violaceum in a concentration-dependent manner. Octopromycin also inhibited alginate production, surface movements (swarming and swimming), and twitching motility of A. baumannnii , confirming its anti-quorum-sensing activity. Multiple metabolic pathways, two-component regulation systems, quorum-sensing, and antibiotic synthesis-related pathways in A. baumannii biofilms were strongly affected by octopromycin treatment. The collective findings indicate that the antibacterial peptide octopromycin may control A. baumannii biofilms through multi-target interactions. Octopromycin could be a desirable therapeutic option for the prevention and control of A. baumannii infections.

Numerous studies have been conducted to prove the calming and stress-reducing effects on humans of visiting aquatic environments. As a result, many institutions have utilized fish to provide entertainment and treat patients. The most common issue in this approach is controlling the movement of fish to facilitate human interaction. This study proposed an interactive robot, a robotic fish, to alter fish swarm behaviors by performing an effective, unobstructed, yet necessary, defined set of actions to enhance human interaction. The approach incorporated a minimalistic but futuristic physical design of the robotic fish with cameras and infrared (IR) sensors, and developed a fish-detecting and swarm pattern-recognizing algorithm. The fish-detecting algorithm was implemented using background subtraction and moving average algorithms with an accuracy of 78%, while the swarm pattern detection implemented with a Convolutional Neural Network (CNN) resulted in a 77.32% accuracy rate. By effectively controlling the behavior and swimming patterns of fish through the smooth movements of the robotic fish, we evaluated the success through repeated trials. Feedback from a randomly selected unbiased group of subjects revealed that the robotic fish improved human interaction with fish by using the proposed set of maneuvers and behavior.

Ultrafast dynamics in nanophotonic materials is attracting increasing attention from the perspective of exploring new physics in fundamental science and expanding functionalities in various photonic devices. In general, such dynamics is induced by external stimuli such as optical pumping or voltage application, which becomes more difficult as the optical power to be controlled becomes larger owing to the increase in the energy required for the external control. Here, we demonstrate a concept of the self-evolving photonic crystal, where the spatial profile of the photonic band is dynamically changed through carrier-photon interactions only by injecting continuous uniform current. Based on this concept, we experimentally demonstrate short-pulse generation with a high peak power of 80 W and a pulse width of <30 ps in a 1-mm-diameter GaAs-based photonic crystal. Our findings on self-evolving carrier-photon dynamics will greatly expand the potential of nanophotonic materials and will open up various scientific and industrial applications., (© 2023. The Author(s).)

Multidrug-resistant members of the Klebsiella pneumoniae complex have become a threat to human lives and animals, including aquatic animals, owing to the limited choice of antimicrobial treatments. Bacteriophages are effective natural tools available to fight against multidrug-resistant bacteria. The bacteriophage KPP-1 was found to be strictly lytic against K. variicola , a multidrug-resistant isolate, producing clear plaques. The genome sequence analysis of KPP-1 revealed that it comprised 143,369 base pairs with 47% overall GC content. A total of 272 genes (forward 161, complementary 111) encode for 17 tRNAs and 255 open reading frames (ORFs). Among them, 32 ORFs could be functionally annotated using the National Center for Biotechnology Information (NCBI) Protein Basic Local Alignment Search Tool (BLASTp) algorithm while 223 were found to code for hypothetical proteins. Comparative genomic analysis revealed that the closest neighbor of KPP-1 can be found in the genus Mydovirus of the subfamily Vequintavirinae . KPP-1 not only markedly suppressed the growth of the host but also worked synergistically with ampicillin. Useful genes for pathogen control such as endolysin (locus tag: KPP&#95;11591) were found to have activity against multidrug-resistant isolate of K. variicola . Further studies are necessary to develop a strategy to control the emerging pathogen K. variicola using bacteriophages such as KPP-1.