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Photothermal therapy (PTT) is widely used in wound healing because it produces heat under near‐infrared irradiation, eliminating bacterial infections. However, excessive production of reactive oxygen species (ROS) occurs during PTT, which causes oxidative stress damage. In this study, a nanozyme, PDA‐MnO2 (PM), is synthesized and encapsulated in the needle tip layer of a bi‐layer GelMA microneedle patch (PbMP), which has excellent mechanical properties and can easily penetrate the skin. In a study involving an SD rat wound model infected with S. aureus, the PbMP significantly accelerated the healing process of bacterially challenged wounds, resulting in better blood vessel growth, cell proliferation, and collagen biosynthesis than other wound dressings. The experiment shows that the PM nanoparticles in PbMP improve photothermal conversion efficiency and activate SOD and CAT, resulting in an efficient cascade enzyme reaction system to eliminate ROS during the PTT process. This study describes a highly effective nanozyme hydrogel microneedle platform with photothermal synergistic antibacterial effects on wound healing. [ABSTRACT FROM AUTHOR]

Bacillus species are among the most studied and commercially exploited biocontrol agents of plant‐parasitic nematodes. These antagonists may control nematodes by producing toxic or repellent substances, inducing systemic resistance in plants and disrupting nematode chemotaxis. Understanding the mechanism of action of antagonists increases the likelihood of success for microbiological nematicides under field conditions. Therefore, the objective of this work was to elucidate the mechanisms of action of Bacillus amyloliquefaciens strain BaNCT02 against Meloidogyne incognita. We assessed the potential of this strain for forming biofilm in roots and producing volatile and non‐volatile toxic substances. BaNCT02 did not induce systemic resistance in tomato plants against M. incognita. Scanning electron microscopy and chemotaxis analyses revealed that the bacteria form a biofilm on soybean roots and 67% of second‐stage juveniles of M. incognita are repelled by common bean roots treated with the antagonist. Additionally, BaNCT02 produces substances with toxic effects against eggs and juveniles of M. incognita, including volatile organic compounds such as 2‐undecanone and 2‐heptanone, as well as non‐volatile metabolites like proteases and chitinases. The suppressive effect of these substances on hatching and mortality of juveniles varied from approximately 70% to more than 90%. We concluded that B. amyloliquefaciens BaNCT02 forms a biofilm on root surfaces and produces volatile and non‐volatile metabolites with nematicidal and repellent effects against M. incognita. [ABSTRACT FROM AUTHOR]

Polyamide 6 (PA6) fiber has the advantages of high strength and good wear resistance. However, it is still challenging to effectively load inorganic antibacterial agents into polymer substrates without antimicrobial activity. In this work, graphene oxide is used as a carrier, which is modified with an aminosilane coupling agent (AEAPTMS) to enhance the compatibility and antimicrobial properties of the inorganic material, as well as to improve its thermal stability in a high‐temperature melting environment. Cuprous oxide‐loaded aminated grapheme (Cu2O‐GO‐NH2) is constructed by in situ growth method, and further PA6/Cu2O‐GO‐NH2 fibers are prepared by in situ polymerization. The composite fiber has excellent washing resistance. After 50 times of washing, its bactericidal rates against Bacillus subtilis and Escherichia coli are 98.85% and 99.99%, respectively. In addition, the enhanced compatibility of Cu2O‐GO‐NH2 with the PA6 matrix improves the orientation and crystallinity of the composite fibers. Compared with PA6/Cu2O‐GO fibers, the fracture strength of PA6/Cu2O‐GO‐NH2 fibers increases from 3.0 to 4.2 cN/dtex when the addition of Cu2O‐GO‐NH2 is 0.2 wt%. Chemical modification and in situ concepts help to improve the compatibility of inorganic antimicrobial agents with organic polymers, which can be applied to the development of medical textiles. [ABSTRACT FROM AUTHOR]

The population growth and the regular breakout of Nilaparvata lugens pose a significant risk to rice cultivation. Four different N. lugens biotypes have been identified worldwide, with biotype 4 being the most destructive and prevalent throughout Asia, particularly in India. Therefore, a rice variety with multiple resistance genes/alleles is required for effective management of N. lugens. Hence, 191 rice genotypes collected from various parts of India were evaluated for resistance to N. lugens. Further, SSR markers representing 23 different N. lugens resistant (R) genes were assayed to identify genomic regions associated with resistance. The results of the genetic analysis showed that the average genetic diversity value of all markers was 0.165 and polymorphic information content of 0.145 for all the markers used. The population structure and cluster analysis divided the studied genotypes into three distinct groups, with resistant genotypes grouped separately. These findings were confirmed by the principal coordinate analysis, which categorized resistant genotypes, moderately resistant genotypes, and susceptible genotypes into distinct components. Additionally, 90% of the genetic variation was between individuals of populations and 10% between the populations. Marker‐trait association study through mixed linear model and generalized linear model identified six SSR markers such as RM6732 (Bph15), RM314 (Bph6), RM16999 (Bph6), RM7 (QBph3), RM401 (bph4), and RM7102 (Bph1), which were significantly associated with various phenotypic parameters, such as feeding mark, honeydew excretion, percent damage and nymphal survival. The resistant genes identified in these genotypes could help in the marker‐assisted rice variety development with durable resistance against N. lugens. [ABSTRACT FROM AUTHOR]

ABSTRACT Cotton–melon aphid (Aphis gossypii) is a highly destructive pest that causes serious yield losses in cucumber production. IL52, a Cucumis hystrix introgression line of cucumber, exhibits resistance to a number of diseases and also shows strong resistance to aphids. To characterize the type of aphid resistance in IL52, we designed a separate leaf‐disc/no‐choice test and free‐choice test to examine antibiosis and antixenosis, respectively. Our results indicated that IL52 displayed antixenosis resistance to aphids. In other words, when planted with other lines such as CCMC, IL52 was not favourable to aphids. To dissect the genetic basis of antixenosis resistance in IL52, we evaluated a mapping population of 155 lines from CCMC × IL52–derived F7:8 RIL using free‐choice test for aphid resistance. A major‐effect QTL on Chr2, designated as qRag2.1 (Resistant to A. gossypii), was identified as being significantly associated with aphid resistance. The QTL qRag2.1 was mapped to an interval flanked by markers UW085197 and SSR11909, spanning a physical location of 15.14–19.07 Mb, which explained 12.74%–14.03% of the phenotypic variance. Analysis of polymorphisms between the parental lines using resequencing data revealed one gene, CsaV3_2G018180, with three nonsynonymous amino acid substitutions and a 6‐bp InDel in its coding sequence (CDS). CsaV3_2G018180 encodes a pectinesterase/pectinesterase inhibitor enzyme, designated as CsPEI, which has been reported to regulate pectin methylesterase activity that is implicated in various biological processes. The relative expression level of CsPEI was induced in IL52 post aphid infestation, suggesting it could be a potential candidate gene for aphid resistance. [ABSTRACT FROM AUTHOR]

The management of infected wounds is always of great significance and urgency in clinical and biomedical fields. Recent efforts in this area are focusing on the development of functional wound patches with effective antibacterial, drug delivery, and sensor properties. Here, we present novel hyaluronic acid (HA) microneedle patches with these features by encapsulating aminobenzeneboronic acid‐modified gold nanoclusters (A‐GNCs) for infected wound management. The A‐GNCs loaded microneedle patches were derived from negative‐mold replication and showed high mechanical strength to penetrate the skin. The release of the A‐GNCs was realized by the degradation of HA, and the self‐monitor of the released actives was based on the dynamic bright orange fluorescence emitted from A‐GNCs under ultraviolet radiation. As the A‐GNCs could destroy bacteria membranes, the microneedle patches were with excellent in vitro antibiosis ability. Based on these features, we have demonstrated the bacteria inhibition, residual drug self‐monitoring, and wound healing promotion abilities of the microneedle patches in Escherichia coli‐ or Staphylococcus aureus‐infected wound management. These results indicated the great potential of such A‐GNCs loaded microneedle patches for clinical applications. [ABSTRACT FROM AUTHOR]

Penicillium expansum is a fungal pathogen of pome fruit, causing the economically important disease of apple blue mould. The fungus is also important due to its ability to produce the mycotoxin patulin. A strain of Aureobasidium spp. (UC14) was assessed for controlling P. expansum and patulin production in a series of in vitro antibiosis experiments. Volatile and non‐volatile metabolites reduced growth of P. expansum on average by 50%. To assess UC14 efficacy on apples in vivo, different concentrations of cellular suspension were assayed. The concentration 1 × 108 cells/mL was the most effective, completely suppressing apple fruits blue mould symptoms. The antagonism of UC14 was further demonstrated by the very low amount of pathogen DNA in treated fruits detected by qPCR. During cold storage, Aureobasidium strain UC14 persisted on fruits and reduced disease severity by 82.5% and 89.8%, for 'Golden delicious' and 'Fuji' apples, respectively. Aureobasidium strain UC14 reduced patulin on 'Golden delicious' and 'Fuji' apples by 98.1% and 96.2% with respect to the control, demonstrating good efficacy as a potential biological control agent (BCA), so becoming an interesting candidate for use as BCA in the postharvest phase. [ABSTRACT FROM AUTHOR]

China is often considered as motivated by a desire to challenge the international status quo, a challenge the West is trying to mitigate. Social constructivists account for this challenge via a norm of nationalistic assertiveness in Chinese foreign policy; a norm constructed in the synergetic relationship between China's Communist Party and its nationalist movement. However, this work argues that Chinese foreign policy is motivated, in part, by nationalist pressure arising from an antagonistically symbiotic relationship between the Communist Party and China's nationalist movement. This understanding is significant as it indicates that western policies are paradoxically factoring in the emergence of a challenger China. © 2023 Victoria University of Wellington and John Wiley & Sons Australia, Ltd. [ABSTRACT FROM AUTHOR]

Phyllosphere colonizing antagonistic bacterial isolates were evaluated for managing major rice foliar diseases, namely brown spot caused by Bipolaris oryzae and sheath rot caused by Sarocladium oryzae. Among these various isolates, Pseudomonas aeruginosa isolate 1 effectively inhibited the mycelial growth of B. oryzae and S. oryzae. The volatile compounds of Bacillus subtilis isolates effectively inhibited the mycelial growth of S. oryzae and B. oryzae. Non‐volatile compounds of P. aeruginosa isolate 2 and B. subtilis isolate 1 recorded the maximum inhibition of mycelial growth of B. oryzae and S. oryzae, respectively. P. aeruginosa isolates produced fluorescent pigments and hydrogen cyanide (HCN), whereas isolates of Bacillus spp. did not. All the isolates of P. aeruginosa and Bacillus spp. produced protease enzymes. P. aeruginosa isolates solubilized phosphate, whereas isolates of Bacillus spp. did not. Rice seeds treated with these bacterial suspensions showed improvement in plant growth parameters. The foliar application of two bacterial strains, namely P. aeruginosa isolate 1 + B. subtilis isolate 1 recorded the minimum brown spot and sheath rot disease incidence. Thus, the present showed that phyllosphere colonizing P. aeruginosa and B. subtilis have the potential application for managing foliar fungal diseases of rice plants. [ABSTRACT FROM AUTHOR]

As a high‐risk trauma, deep burns are always hindered in their repair process by decreased tissue regeneration capacity and persistent infections. In this study, we developed a simultaneous strategy for deep burn wounds treatment using functional nanovesicles with antibacterial and tissue remodeling properties, delivered via a click‐chemistry hydrogel. An aggregation‐induced emission photosensitizer of 4‐(2‐(5‐(4‐(diphenylamino)phenyl)thiophen‐2‐yl)vinyl)‐1‐(2‐hydroxyethyl) pyridin‐1‐ium bromide (THB) with excellent photodynamic properties was first prepared, and then combined with readily accessible adipose stem cells‐derived nanovesicles to generate the THB functionalized nanovesicles (THB@ANVs). The THB@ANVs showed strong antibacterial activity against Gram‐positive bacteria (up to 100% killing rate), and also beneficial effects on tissue remodeling, including promoting cell migration, cell proliferation, and regulating immunity. In addition, we prepared a click‐hydrogel of carboxymethyl chitosan for effective delivery of THB@ANVs on wounds. This hydrogel could be injected to conform to the wound morphology while responding to the acidic microenvironment. In vivo evaluations of wound healing revealed that the THB@ANVs hydrogel dressing efficiently accelerated the healing of second‐degree burn wounds by reducing bacterial growth, regulating inflammation, promoting early angiogenesis, and collagen deposition. This study provides a promising candidate of wound dressing with diverse functions for deep burn wound repair. [ABSTRACT FROM AUTHOR]

Immediate and effective hemostatic treatments for complex bleeding wounds are an urgent clinical demand. Hemostatic materials with characteristics of adhesion, sealing, anti‐infection, and concrescence promotion have drawn growing concerns. However, pure natural multifunctional hemostatic materials with in situ ultrafast self‐gelation are rarely reported. In this study, a hydro‐sensitive collagen/tannic acid (ColTA) natural hemostatic powder is developed that can in situ self‐gel to form adhesive by the non‐covalent crosslinking between tannic acid (TA) and collagen (Col) in liquids. The physical interactions endow ColTA adhesive with the characteristics of instantaneous formation and high adhesion at various substrate surfaces. Crucially, ColTA powder adhesive shows an enhanced adhesion performance in the presence of blood due to the electrostatic interactions between ColTA adhesive and red blood cells, conducive to effective in situ sealing and rapid hemostasis. The biocompatible and hemocompatible ColTA adhesive can effectively control bleeding and seal the wounds of the caudal vein, liver, heart, and femoral arteries in rats. Furthermore, the low‐cost and ready‐to‐use ColTA adhesive powder also possesses good antibacterial and inhibiting biofilm formation ability, and can efficiently regulate immune response by the NF‐κB pathway to promote wound repair, making it a highly promising hemostatic material with great potential for biomedical applications. [ABSTRACT FROM AUTHOR]

Methicillin‐resistant Staphylococcus aureus (MRSA) is threatening human health due to its resistance to multiple antibiotics. Excessive copper (Cu) ions target the lipoylated proteins of tricarboxylic acid cycle of cancer cells, inducing proteotoxic stress and their cuproptosis death. Whether cuproptosis plays a part in killing MRSA by low‐dose supplement of Cu ions remains to be explored. Herein, Cu‐doped hydroxyapatite nanorods (PC) are prepared on polyetheretherketone (PEEK) to resist infection and improve PEEK performance in tissue integration with the assistance of near‐infrared (NIR) irradiation, and the mechanism against MRSA is elucidated. Mild photothermal stimulation increases bacterial membrane permeability, accelerating Cu ions' intake and consequently inducing cuproptosis‐like death of MRSA. It is confirmed by aggregation of dihydrolipoamide S‐acetyltrans‐ferase (DLAT), deactivation of glutathione peroxides 4 (GPX4), and destabilization of Fe─S cluster proteins ferredoxin (FDX1) and lipoyl synthase (LIAS). Fortunately, fibroblast behaviors are upregulated on NIR‐irradiated PC. In vivo, PC with NIR irradiation exhibits outstanding MRSA elimination, reduced inflammation response, and improved biointegration. Overall, it is demonstrated that bacterial cuproptosis‐like death can be induced by Cu ions at a non‐cytotoxic dose when cooperated with mild heat stimulus, and this photothermal strategy of PC has greatly promising application in improving PEEK performance in clinic. [ABSTRACT FROM AUTHOR]

Development of highly efficient and metal‐free photocatalysts for bacterial inactivation under natural light is a major challenge in photocatalytic antibiosis. Herein, we developed an acidizing solvent‐thermal approach for inserting a non‐conjugated ethylenediamine segment into the conjugated planes of 3,4,9,10‐perylene tetracarboxylic anhydride to generate a photocatalyst containing segregated π‐conjugation units (EDA‐PTCDA). Under natural light, EDA‐PTCDA achieved 99.9 % inactivation of Escherichia coli and Staphylococcus aureus (60 and 45 min), which is the highest efficiency among all the natural light antibacterial reports. The difference in the surface potential and excited charge density corroborated the possibility of a built‐in electron‐trap effect of the non‐conjugated segments of EDA‐PTCDA, thus forming a highly active EDA‐PTDA/bacteria interface. In addition, EDA‐PTCDA exhibited negligible toxicity and damage to normal tissue cells. This catalyst provides a new opportunity for photocatalytic antibiosis under natural light conditions. [ABSTRACT FROM AUTHOR]

Microbial inoculants for controlling soil pathogens are an environmentally sustainable approach for attaining agricultural intensification. Charcoal root rot pathogens might threaten global food security and degrade prime agricultural lands. Microbial antagonists to control charcoal root disease were not properly studied with reference to physiological and photochemical basis. This research was aimed to examine the impact of newly isolated microbial biocontrol agents (MBCAs) on growth and photosynthetic efficiency (photosystem II) in pathogen (Macrophomina phaseolina)‐infected plants. The MBCAs (Purpureocillium lilacinum and Aspergillus terreus) were isolated and seeds were coated to improve soil fertility and resilience of agricultural lands. Both MBCAs inhibited the colonization of pathogenic fungus around the roots of host plants. Decline in growth traits was observed due to the detrimental impacts of root rot disease on growth parameters compared with plants treated with M. phaseolina. However, the growth of corn plants in both soils with and without M. phaseolina infestations was substantially improved by treating corn seeds with P. lilacinum and A. terreus. The pathogen drastically reduced the distinct parameters of photosystem II of photosynthesis. However, applying P. lilacinum and A. terreus significantly improved the total performance index (PItot), size, and the number of active reaction centers of photosystem II (Fv/Fo), electron transport rate, electron trapping per absorption (TRO/ABS), electron transport per absorption (ETO/ABS), electron transport per trapping (ETO/TRO), and the efficiency of light reaction (φEo) but downregulates nonphotochemical quenching (NPQ). Our study demonstrates that microbial antagonists offer a more effective, ecofriendly alternative to improve the land to sustainable agriculture. [ABSTRACT FROM AUTHOR]

The pea aphid (PA), Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), can cause significant damage to dry and green peas, Pisum sativum L. (Fabaceae). Identifying pea lines with resistance to PA is important to advance available control measures. This research identified lines and putative genes with resistance to PA in the USDA Pisum sativum Collection located in Pullman, WA, USA, consisting of 301 lines collected worldwide. Eight commercial pea cultivars were also evaluated. A cluster analysis based on the mean number of adults, nymphs, and total aphids that developed on lines 10 days after the start of infestation by a single adult aphid per plant identified six clusters. Cluster 2, consisting of 48 lines, had the lowest aphid fecundity of all clusters with 2.1 adults, 7.3 nymphs, and 9.4 total aphids produced on average. 'Lifter' was the most resistant line based on low aphid fecundity. Lifter is a white‐flowered green dry pea cultivar that can advance PA resistance in food‐type peas. Genotyping by sequencing based on single‐nucleotide polymorphisms (SNPs) were used in genome‐wide association mapping to locate genes or quantitative trait loci (QTL) linked to PA resistance in which three, nine, and six SNPs were associated with resistance to adult, nymph, and total number of PAs that developed on lines, respectively. Seventeen candidate genes were identified in response to PA resistance. The results can effectively be used in breeding programs to target specific genomic regions with PA resistance and in traditional breeding using resistant lines as parents. [ABSTRACT FROM AUTHOR]

BACKGROUND: Helicoverpa armigera is a major pest of pigeonpea (Cajanus cajan). Efforts to develop pigeonpea varieties resistant to H. armigera attack have been met with limited success, despite reports of high levels of resistance to H. armigera in wild relatives of pigeonpea and reports of low to moderate levels of resistance in cultivated varieties. Here we examined H. armigera oviposition preference and larval performance on whole plants of three cultivars of short-duration pigeonpea: a susceptible control (ICPL 87) and two cultivars with purported host–plant resistance (ICPL 86012 and ICPL 88039). RESULTS: In our no-choice oviposition experiment, H. armigera laid similar numbers of eggs on all three cultivars tested, but under choice conditions moths laid slightly more eggs on ICPL 88039. Larval growth and development were affected by cultivar, and larvae grew to the largest size (weight) and developed fastest on ICPL 86012. Moths laid most of their eggs on floral structures, sites where subsequent early instar larvae overwhelmingly fed. Experimentally placing neonate larvae at different locations on plants demonstrated that larvae placed on flowers experienced greater survival, faster development, and greater weight gain than those placed on leaves. The type and density of trichomes (a potential resistance trait) differed among cultivars and plant structures, but larvae selected to feed at sites where trichomes were absent. CONCLUSION: Future work examining host–plant resistance against H. armigera should incorporate the behavioural preference of moths and larvae in experiments using whole plants as opposed to bioassays of excised plant parts in Petri dishes. [ABSTRACT FROM AUTHOR]

Background. The self-locating peritoneal dialysis (PD) catheter, contains a tungsten tip. The effects of magnetic resonance (MR) on the catheter were evaluated, emphasizing its MR signal, artifacts, ferromagnetism, and possible heating production during the MR sequences. Methods. The catheter was studied in an ex vivo model using a 1.5T MR system and placed into a plastic box containing saline solution. Acquisitions on coronal and axial planes were obtained on fast gradient-echo T1-weighted and fast spin-echo T2-weighted. In vivo abdominal MR exams were also carried out. Results. Overall, the catheter had good visibility. In all sequences, an extensive paramagnetic blooming artifact was detected at the level of the tip tungsten ballast, with a circular artifact of 5 cm in diameter. The catheter showed no magnetic deflection, rotation, or movements during all MR sequences. After imaging, the temperature of the saline solution did not change compared to the basal measurement. Patients safely underwent abdominal MR. Conclusions. The results point to the possibility of safely performing MR in PD patients carrying the self-locating catheter. The self-locating PD catheter is stable when subjected to a 1.5T MR system. However, it creates some visual interference, preventing an accurate study of the tissues surrounding the tungsten tip. [ABSTRACT FROM AUTHOR]

Purpose: Treatment of struvite kidney stones requires complete surgical stone removal combined with antibiotic therapy to eliminate urinary tract infections and preventive measures to reduce stone recurrence. The optimal duration of antibiotic therapy is unknown. We sought to determine if 2‐ or 12‐weeks of antibiotics post percutaneous nephrolithotomy (PNL) for infection stones resulted in better outcomes for stone recurrence and positive urine cultures. Material and methods: This multi‐center, prospective randomized trial evaluated patients with the clinical diagnosis of infection stones. Patients were randomized to 2‐ or 12‐weeks of postoperative oral antibiotics (nitrofurantoin or culture‐specific antibiotic) and included if residual fragments were ≤4 mm on computed tomography imaging after PNL. Imaging and urine analyses were performed at 3‐, 6‐, and 12‐months post‐procedure. Results: Thirty‐eight patients were enrolled and randomized to either 2‐weeks (n = 20) or 12‐weeks (n = 18) of antibiotic therapy post‐PNL. Eleven patients were excluded due to residual fragments >4 mm, and 3 patients were lost to follow‐up. The primary outcome was the stone‐free rate (SFR) at 6 months post‐PNL. At 3‐, 6‐, and 12‐months follow‐up, SFRs were 72.7% versus 80.0%, 70.0% versus 57.1%, 80.0% versus 57.1% (p = ns), between 2‐ and 12‐week‐groups, respectively. At 3‐, 6‐, and 12‐months follow‐up, positive urine cultures were 50.0% versus 37.5%, 50.0% versus 83.3%, and 37.5% versus 100% between 2‐ and 12‐week groups, respectively (p = ns). Conclusions: For patients with stone removal following PNL, neither 2‐weeks nor 12‐weeks of postoperative oral antibiotics is superior to prevent stones and recurrent positive urine cultures. [ABSTRACT FROM AUTHOR]

Moraxella osloensis, a gram-negative rod-shaped bacterium found on human skin, produces 4-methyl-3-hexenoic acid, contributing to clothing and body malodor. M. osloensis is resistant to UV light, drying, and antimicrobials, making its eradication challenging. As the skin is low in nutrients, commensal bacteria compete for resources and use diverse strategies to inhibit their competitors. Therefore, skin-derived bacteria that exhibited growth-inhibitory activity against M. osloensis were searched. Screening skin-derived bacteria using a coculture halo assay revealed that Bacillus xiamenensis formed an inhibition zone with M. osloensis. Coculture plates were extracted with ethyl acetate and fractionated using a silica gel column and preparative thin-layer chromatography to isolate the active compound from the B. xiamenensis metabolites. Nuclear magnetic resonance spectroscopy identified the active compound as indole-3-carboxaldehyde, which has low toxicity in humans. At soluble concentrations, indole-3-carboxaldehyde does not inhibit the growth of other bacteria, such as Staphylococcus aureus, Escherichia coli, and Bacillus subtilis, suggesting M. osloensis is highly sensitive to indole-3-carboxaldehyde. These findings highlight B. xiamenensis as a promising candidate for the development of a skin probiotic to promote skin health and combat malodor-causing bacteria., (© 2024 The Author(s). MicrobiologyOpen published by John Wiley & Sons Ltd.)

Enzymes play an indispensable role in biosystems, catalyzing a variety of chemical and biochemical reactions with exceptionally high efficiency and selectivity. These features render them uniquely positioned in developing novel catalytic systems and therapeutics. However, their practical application is largely hindered by the vulnerability, low reusability and the inability to overcome the biological barriers of enzymes. Silica‐based nanoparticles (SNPs) are a classic family of nanomaterials with tunable physicochemical properties, making them ideal candidates to address the intrinsic shortcomings of natural enzymes. SNPs not only improve the activity and durability of enzymes, but also provide precise spatiotemporal control over their intracellular as well as systemic biodistributions for boosting the catalytic outcome. Herein, the recent progress in SNPs for enzyme immobilization and delivery is summarized. The therapeutic applications, including cancer therapy and bacterial inhibition, are particularly highlighted. Our perspectives in this field, including current challenges and possible future research directions are also provided. [ABSTRACT FROM AUTHOR]

The pea aphid (PA), Acyrthosiphon pisum (Harris) (Hemiptera: Aphididae), can cause complete yield loss in lentil, Lens culinaris Medik. (Fabaceae, Leguminosae), if not managed properly. Determining lentil genetic resources with resistance to PA is important for integrated pest management (IPM) in production areas worldwide. The objectives of this study were to identify genetic resources and genes associated with resistance to PA in 188 lines of the USDA Lentil Single Plant Core Collection. A cluster analysis of the mean number of adults, nymphs, and total aphids that developed on lentil lines 10 days after infestation with a single aphid identified four clusters associated with aphid resistance: 20 lines were considered resistant, 99 moderately resistant, 51 moderately susceptible, and 18 susceptible. PIs 329157 LSP and 432085 LSP, originating from Iran, demonstrated the best resistance when assessing antibiotic and antixenotic properties. Genotyping‐by‐sequencing (GBS)‐based single nucleotide polymorphisms (SNPs) were used for genome‐wide association mapping to locate genes or quantitative trait loci (QTL) associated with PA resistance traits, in which six, four, and three SNPs were associated with low numbers of PA adults, nymphs, and total aphids that developed on lentil lines, respectively. Fifteen candidate genes were identified relating to PA resistance. The results can effectively be used in molecular lentil breeding programs to target specific genomic regions associated with PA resistance, as well as in traditional breeding, using lines identified as highly PA‐resistant as parents, to develop durable resistance in lentil cultivars. [ABSTRACT FROM AUTHOR]

There are no standard protocols for assessing antibiosis in soybean, Glycine max (L.) (Fabaceae), cultivars to lepidopterans, including tobacco budworm, Chloridea virescens (Fabricius) (Lepidoptera: Noctuidae), an important species that causes damage to soybean crops in several production regions. This study was conducted to assess methodologies to determine the optimal combination of larval density, confinement container size, and plant structure in soybean antibiosis assays to C. virescens. In addition, primary and secondary metabolites in plant structures were analyzed to elucidate potential chemical resistance mechanisms against this lepidopteran. Antibiosis assays to C. virescens in resistant (IAC‐100) and susceptible (BR‐16) soybean cultivars were performed using three larval densities (one, two, and three larvae), two confinement container sizes (150 and 300 ml), and combinations of soybean plant structures (leaves, uncut pods, leaves + uncut pods, cut pods, and leaves + cut pods). Phenol, tannin, fiber, and lignin contents were quantified in the leaves, uncut pods, and grains of the soybean cultivars and related to biological development of C. virescens. Resistance levels in soybean cultivars in antibiosis assays were best differentiated using one larva per 150‐ml confinement container, fed only on soybean leaves. Higher contents of condensed tannins in the leaves of IAC‐100 cultivar may be one of the main chemical mechanisms of resistance to C. virescens. Our study is the first to determine the optimal combination of larval density, confinement container size, and plant structure for antibiosis assays in soybean cultivars to C. virescens. The developed protocol will benefit high‐throughput phenotyping in genetic breeding programs to obtain cultivars resistant to lepidopterans for use in integrated pest management. [ABSTRACT FROM AUTHOR]

Current treatments for implant‐associated infection remain unsatisfactory due to secondary infection and excessive inflammation, which impairs osseointegration. Herein, an interfacial functionalization strategy is proposed by the integration of a carbon monoxide gas (CO) nanogenerator on titanium implants, followed by covalently grafting arginine‐glycine‐aspartic acid (RGD) polypeptide. Under near‐infrared light (NIR) irradiation, the designed surface displays great light‐activatable antibiosis through CO‐potentiated mild photothermal therapy. Interestingly, the functionalized surface exerts a CO‐mediated anti‐inflammatory effect by activating the expression of heme oxygenase (HO‐1), and inducing the down‐regulation of p38 mitogen‐activated protein kinase (MAPK) and nuclear factor kappa B (NFκB) (p50/p65). More importantly, the combination of CO delivery and RGD immobilization drives the polarization of lipopolysaccharide (LPS)‐stimulated M1‐phenotype macrophages towards anti‐inflammatory M2‐phenotype through a potential Janus kinase 1/signal transducer and activator of transcription 6 (JAK1/STAT6) pathway, thereby remodeling the damaged microenvironment into a pro‐regenerative microenvironment. In a rat model of implant‐associated infection, the designed surface effectively eliminates the residual bacteria, alleviates the accompanying inflammation and mediates macrophage‐mediated immunomodulation, resulting in good osteogenesis. Together, these findings are a first report on the therapeutic potential of CO signal in the cascade of immunomodulation‐osteogenic differentiation. The functionalized implant may serve as a promising candidate in implant replacement surgeries. [ABSTRACT FROM AUTHOR]

Construction of versatile nanotemplate bearing inherent distinctive functions and prominent drug‐carrying capability is an appealing yet significantly challenging task. Here, inspired by the guiding role of surfactant in preparing nanoparticles, an amphiphilic aggregation‐induced emission (AIE) photosensitizer, namely MeOTTVP, is synthesized with attractive near‐infrared (NIR) emission and high‐performance reactive oxygen species production, and followed by dual‐templating‐assisted one‐pot method involving MeOTTVP as the skeleton to fabricate organosilica nanoparticles (AIE‐ONs). The presented AIE‐ONs perfectly inherit the functions of MeOTTVP, and are also capable of loading antibiotics and anticancer drugs. Doxorubicin can be assembled on AIE‐ONs and then capped with hyaluronic acid, endowing the resulting hybrid with NIR fluorescence imaging‐guided synergetic photodynamic/chemotherapy performance, thereby offering boosted anticancer efficacy and reduced side effects. Furthermore, by loading antibiotic rifampicin, the newly obtained AIE‐ONs integrating chemo‐photodynamic antibacterial functions provide broad‐spectrum antibacterial activity and fluorescence monitoring behavior. This study thus not only offers a promising strategy to fabricate NIR nanoparticles on a large scale, but also provides useful insights into designing an advanced theranostic protocol for treating both cancer and bacterial infections. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have recently emerged as antibacterial agents and have attracted considerable attention owing to their fascinating merits of small size, facile fabrication, and surface functionalization. Most of them are involved in external light activation or hybridization with other functional nanomaterials. Herein, we present peroxidase‐like Cu‐doped CDs (Cu‐CDs) for in vitro antibacterial applications. The unique peroxidase‐mimicking property of the Cu‐CDs was demonstrated by tetramethylbenzidine chromogenic assay, electron paramagnetic resonance spectra, and hydroxy radical probe. Escherichia coli and Staphylococcus aureus were chosen as representative gram‐negative/positive models against which Cu‐CDs exhibited superior antimicrobial activity even at a dosage down to 5 μg/mL. A possible mechanism of action was that the Cu‐CDs triggered a catalytic redox reaction of endogenous H2O2 and glutathione depletion in the bacteria cells, with subsequent oxidative stress and membrane disruption. This work provides a new strategy for the design of microenvironment‐responsive antimicrobial nano‐agents. [ABSTRACT FROM AUTHOR]

The aims of this study were to evaluate in vitro the probiotic characteristics of two isolates of Pediococcus pentosaceus (P47 and P97), and their viability in Minas Frescal cheese. The evaluation of probiotic characteristics of isolates was performed through gastrointestinal tract tolerance, autoaggregation, coaggregation, hydrophobicity, β‐galactosidase activity, and antagonism against bacterial pathogens. Safety aspects were evaluated through antimicrobial susceptibility and cytotoxicity assay. Minas Frescal was produced with isolates (P47 and P97), and evaluated by microbiological, physicochemical, and sensory analysis. The isolates demonstrated probiotic potential in vitro, and none of them showed cytotoxicity. Furthermore, when used in the production of Minas Frescal cheese, both isolates remained viable (cell concentrations above 7 log CFU/ml) during 28 days of storage at 4°C, and the probiotic product was sensorially accepted by the evaluators. Therefore, isolates P47 and P97 can be considered promising microorganisms for the manufacture of probiotic cheese. Novelty impact statement: Pediococcus pentosaceus P47 and P97 have no indication of pathogenicity and cytotoxicity. P. pentosaceus P47 and P97 have higher adhesion to epithelial cells than Listeria monocytogenes. P. pentosaceus P47 and P97 maintained their viability >7 log CFU/g in cheese over time in storage. [ABSTRACT FROM AUTHOR]

Summary: The rhizosphere is a multitrophic environment, and for soilborne pathogens such as Fusarium oxysporum, microbial competition in the rhizosphere is inevitable before reaching and infecting roots. This study established a tritrophic interaction among the plant growth‐promoting rhizobacterium Burkholderia ambifaria, F. oxysporum and Glycine max (soybean) to study the effects of F. oxysporum genes on shaping the soybean microbiota. Although B. ambifaria inhibited mycelial growth and increased bacterial propagation in the presence of F. oxysporum, F. oxysporum still managed to infect soybean in the presence of B. ambifaria. RNA‐Seq identified a putative F. oxysporum secretory β‐lactamase‐coding gene, FOXG_18438 (abbreviated as Fo18438), that is upregulated during soybean infection in the presence of B. ambifaria. The ∆Fo18438 mutants displayed reduced mycelial growth towards B. ambifaria, and the complementation of full Fo18438 and the Fo18438 β‐lactamase domain restored mycelial growth. Using the F. oxysporum wild type, ∆Fo18438 mutants and complemented strains with full Fo18438, Fo18438 β‐lactamase domain or Fo18438 RTA1‐like domain for soil inoculation, 16S rRNA amplicon sequencing revealed that the abundance of a Burkholderia operational taxonomic unit (OTU) was increased in the rhizosphere microbiota infested by the strains with Fo18438 β‐lactamase domain. Non‐metric multidimensional scaling and PICRUSt2 functional analysis revealed differential abundance for the bacterial β‐lactam‐related functions when contrasting the genotypes of F. oxysporum. These results indicated that the Fo18438 β‐lactamase domain provides F. oxysporum with the advantage of growing into the soybean rhizosphere, where β‐lactam antibiosis is involved in microbial competition. Accordingly, this study highlights the capability of an F. oxysporum gene for altering the soybean rhizosphere and taproot microbiota. [ABSTRACT FROM AUTHOR]

Probiotics, live microorganisms that, when administered in adequate amounts, confer a health benefit on the host, offer an alternative to antibiotics and have become popular among shrimp farmers for use in the regulation of pond water quality, promotion of shrimp growth and the prevention of disease. Most shrimp probiotics are selected for testing based on their ability to competitively exclude pathogens through bacterial antagonism assays, although the mechanisms of pathogen exclusion are rarely investigated. In this review, we provide a comprehensive overview of the mechanisms of competitive exclusion (interference and exploitation competition) by species screened and subsequently identified as shrimp probiotics based on their ability to inhibit the growth of pathogenic bacteria in vitro. We show that the current methods used to identify potential probiotics preferentially select for interference‐based competitive mechanisms and may overlook the potential of many species to be considered a probiotic. Furthermore, we show that the efficiency of a probiotic in vivo may be improved by considering the suitability of competitive strategies to shrimp farming conditions. We highlight important limitations and future directions for the screening and identification of probiotics in shrimp aquaculture, to aid in the development of effective and sustainable microbial management strategies. [ABSTRACT FROM AUTHOR]

Background: Co‐administration of multiple intravenous (IV) medicines down the same lumen of an IV catheter is often necessary in the intensive care unit (ICU) while ensuring medicine compatibility. Aims and objectives: This study explores ICU nurses' views on the everyday practice surrounding co‐administration of multiple IV medicines down the same lumen. Design: Qualitative study using focus group interviews. Methods: Three focus groups were conducted with 20 ICU nurses across two hospitals in the Thames Valley Critical Care Network, England. Participants' experience of co‐administration down the same lumen and means of assessing compatibility were explored. All focus groups were recorded, transcribed verbatim, and analysed using thematic analysis. Functional Resonance Analysis Method was used to provide a visual representation of the co‐administration process. Results: Two key themes were identified as essential during the process of co‐administration, namely, venous access and resources. Most nurses described insufficient venous access and lack of compatibility data for commonly used medicines (eg, analgesics and antibiotics) as particular challenges. Strategies such as obtaining additional venous access, prioritizing infusions, and swapping line of infusion were used to manage IV administration problems where medicines were incompatible, or of unknown or variable compatibility. Conclusions: Nurses use several workarounds to manage commonly encountered medication compatibility problems that may lead to delays in therapy. Organizations should review and tailor compatibility resources towards commonly administered medicines using an interdisciplinary approach. Developing a clinical decision‐making pathway to minimise variability while promoting safe co‐administration practice should be prioritised. Relevance to clinical practice: This study highlights several ways ICU nurses are able to manage challenges associated with co‐administration and the need for the development of a more robust and comprehensive compatibility resource that is relevant to everyday practice through collaboration between nurses and pharmacists. [ABSTRACT FROM AUTHOR]

The cabbage aphid, Brevicoryne brassicae (L.) (Hemiptera: Aphididae), is distributed throughout the tropical and subtropical areas of the world. The main crops attacked by B. brassicae are cabbage, collard greens, broccoli, Brussels sprouts, and cauliflower. To survive the attack of pest insects, plants have evolved various resistance mechanisms that may affect pest feeding behavior. The use of electronic monitoring through EPG (electrical penetration graph) can help characterize and distinguish the resistance mechanisms involved. This study evaluated the feeding behavior of B. brassicae in eight genotypes of collard greens, Brassica oleraceae L. var. acephala (Brassicaceae), exhibiting antixenosis and/or antibiosis resistance to this insect. Possible correlations were established between the glucosinolate levels, the hardness, and the epicuticular wax on the leaves vs. aphid feeding behavior. On the genotypes 22V, 5E, and 27VA, for which many 'potential drop' waves were performed, aphid development was slower, indicating antixenosis as resistance type. Aphids on the genotypes 22V and 24X required more time until accessing the phloem, also suggesting antixenosis as resistance category. Genotypes 22V and PE had hard leaves, which also points at antixenosis. Genotypes 20T and HS had higher total wax and wax mg−1. Feeding parameters on ARI and 24X were similar to those observed on HS; antibiosis is likely to be the predominant resistance category of this germplasm. Because HS was considered as a susceptible standard genotype in this study, a higher gluconapin amount indicates that this compound does not influence cabbage aphid feeding behavior. The present study confirms that analysis of the physical and chemical aspects of collard greens genotypes by the EPG technique can provide a useful approach for the study of plant resistance to cabbage aphids. [ABSTRACT FROM AUTHOR]

Summary: Competition is a major type of interaction between fungi and bacteria in soil and is also an important factor in suppression of plant diseases caused by soil‐borne fungal pathogens. There is increasing attention for the possible role of volatiles in competitive interactions between bacteria and fungi. However, knowledge on the actual role of bacterial volatiles in interactions with fungi within soil microbial communities is lacking. Here, we examined colonization of sterile agricultural soils by fungi and bacteria from non‐sterile soil inoculums during exposure to volatiles emitted by soil‐derived bacterial communities. We found that colonization of soil by fungi was negatively affected by exposure to volatiles emitted by bacterial communities whereas that of bacteria was barely changed. Furthermore, there were strong effects of bacterial community volatiles on the assembly of fungal soil colonizers. Identification of volatile composition produced by bacterial communities revealed several compounds with known fungistatic activity. Our results are the first to reveal a collective volatile‐mediated antagonism of soil bacteria against fungi. Given the better exploration abilities of filamentous fungi in unsaturated soils, this may be an important strategy for bacteria to defend occupied nutrient patches against invading fungi. Another implication of our research is that bacterial volatiles in soil atmospheres can have a major contribution to soil fungistasis. [ABSTRACT FROM AUTHOR]

BACKGROUND: The walnut leaf gall mite (WLGM) (Aceria tristriata (Nalepa)) is one of the major pests of walnut in western Iran. The use of a resistant variety is an economical and environment‐friendly method of pest control. The aim of the present study is to assess resistance of some walnut cultivars and genotypes in relation to WLGM. Also, the current research aimed to study a possible correlation between resistance with plant morphological and biochemical features. RESULTS: Based on the leaf damage index (number of galls per leaf and plant, the percentage of infested leaves and the percentage of leaf injury area) induced by WLGM, the studied cultivars and genotypes were classified into four groups from susceptible to approximately resistant. Free‐choice experiments indicated that Jamal and Chandler cultivars were colonized by lower densities of WLGM, whereas Seedling, Hartly, Lara and Z60 hosted denser populations. In antibiosis assay, the highest mite density was created in the galls on the leaves of Seedling and Hartly, whereas lowest mite density was observed in galled leaves of Chandler and Jamal cultivars. CONCLUSION: Results from biochemical assays showed that nearly all evaluated biomarkers had negative correlation with number of galls per leaf and mite density. Generally, resistant cultivars (Chandler, Jamal and Pedro) significantly produced defensive compounds more than those of controls after mite infestation. Also, it is worth noting that, the content of photosynthetic pigments significantly reduced in susceptible cultivars after mite infestation. The obtained results from this study can be useful for provisional resistance screening. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Graphyne, a theorized carbon allotrope possessing only sp‐ and sp2‐hybridized carbon atoms, holds great potentials in many fields, especially in catalysis and energy‐transfer/storage devices. Using a bottom‐up strategy, we synthesized a new N‐doped graphyne analogue, triazine‐ and 1,4‐diethynylbenzene‐based graphyne TA‐BGY, in solution in gram‐scale. The unique sp/sp2 carbon‐conjugated TA‐BGY possesses an extended porous network structure with a BET surface area of approximately 300 m2 g−1. Owing to its low optical band gap (1.44 eV), TA‐BGY was expected to have many applications, which were exemplified by the photodegradation of methyl orange and photocatalytic bacterial inactivation. [ABSTRACT FROM AUTHOR]

Antibiosis and resource competition are major drivers shaping the assembly, diversity and functioning of microbial communities. While it is recognized that competition is sensitive to environmental conditions, it is unclear to what extent this mediated by the availability of different carbon resources.Here, we used a model laboratory system to directly test this by exploring how carbon resource richness and identity shape resource competition and antibiosis between plant probiotic Bacillus amyloliquefaciens and phytopathogenic Ralstonia solanacearum bacteria. We found that while sugars typically promoted B. amyloliquefaciens growth, organic and amino acids increased the production of both bacillaene and macrolactin antibiotics and the direct inhibition of R. solanacearum. In contrast, when multiple different carbon resources were available, B. amyloliquefaciens could efficiently grow and produce antibiotics at the same time.Together, these results suggest that high carbon resource richness allows concurrent expression of growth‐ and antibiosis‐related traits, potentially altering bacterial competitive dynamics and plant growth promotion in microbial communities. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

The beneficial effects of plant‐–bacterial interactions in controlling plant pests have been extensively studied with single bacterial isolates. However, in nature, bacteria interact with plants in multitaxa consortia, systems which remain poorly understood. Previously, we demonstrated that a consortium of five native bacterial isolates protected their host plant Nicotiana attenuata from a sudden wilt disease. Here we explore the mechanisms behind the protection effect against the native pathosystem. Three members of the consortium, Pseudomonas azotoformans A70, P. frederiksbergensis A176 and Arthrobacter nitroguajacolicus E46, form biofilms when grown individually in vitro, and the amount of biofilm increased synergistically in the five‐membered consortium, including two Bacillus species, B. megaterium and B. mojavensis. Fluorescence in situ hybridization and scanning electron microscopy in planta imaging techniques confirmed biofilm formation and revealed locally distinct distributions of the five bacterial strains colonizing different areas on the plant‐root surface. One of the five isolates, K1 B. mojavensis produces the antifungal compound surfactin, under in vitro and in vivo conditions, clearly inhibiting fungal growth. Furthermore, isolates A70 and A176 produce siderophores under in vitro conditions. Based on these results we infer that the consortium of five bacterial isolates protects its host against fungal phytopathogens via complementary traits. The study should encourage researchers to create synthetic communities from native strains of different genera to improve bioprotection against wilting diseases. [ABSTRACT FROM AUTHOR]

Growing away from monocultures - interdependent growth conditions for studying antibacterial and antiphage systems If you google the word "microbiologist", you will likely come upon pictures of scientists scrutinizing bacterial colonies on an agar plate or examining the contents of Erlenmeyer flasks growing I Escherichia coli i to a high cell density. Inter-microbial interactions have also gained attention in the field of infection biology, which is growing from a pure focus on microbe-host interactions towards microbe-microbe-host or phage-microbe-host "ménage-à-trois" scenarios. As with antibiotic resistance, bacteria can horizontally acquire genes that allow them to resist contact-dependent or independent intoxication by other bacteria or phage. [Extracted from the article]

BACKGROUND: The mite Brevipalpus yothersi (Acari: Tenuipalpidae) is of great importance in citriculture because it is a vector of the disease citrus leprosis. The frequency of application of a combination of pesticides has increased because of an increase in the occurrence of economically important pests of citrus. However, the combined effect of acaricide and other insecticides targeting B. yothersi is unknown. The objective of this study was to evaluate the effect of a combination of spirodiclofen and other insecticides on the control of B. yothersi. RESULTS: Analysis using spirodiclofen alone resulted in 97.22% efficiency in the control of B. yothersi on day 7 after application. A combination of spirodiclofen with either phosmet or imidacloprid resulted in 55% and 59% efficiency, respectively. A reduction in the efficiency of mite control by up to 42% was observed when the mites were exposed to a combination of acaricide with other insecticides. CONCLUSIONS: Application of a combination of spirodiclofen with phosmet or imidacloprid compromises the efficiency of acaricide in the control of B. yothersi. © 2018 Society of Chemical Industry Application of a combination of pesticides has increased due to an increase in the simultaneous occurrence of economically important pests. However, combination of spirodiclofen with phosmet or imidacloprid compromises the efficiency of acaricide in the control of Brevipalpus yothersi. [ABSTRACT FROM AUTHOR]

Lactobacillus rhamnosus is a lactic acid bacterium with a diverse ecological habitat. We recently isolated a L. rhamnosus strain (LRB) from a healthy baby-tooth that had naturally fallen out. We determined the whole genome sequence of LRB and found that the isolate is closely genetically related to an intestinal isolate, L. rhamnosus GG (ATCC 53103). However, the LRB genome had lost about a 75-kb segment and undergone a genomic rearrangement. We assessed LRB's capacity to survive in the gut environment, at least temporarily. We found that LRB, like the intestinal isolate ATCC 53103, showed resistance to low pH but sensitive to bile salt. Surprisingly, we found that this oral isolate LRB showed strong antimicrobial activity against a variety of oral streptococci including Streptococcus mutans. The production of antimicrobial activity is dependent on media composition since some media supported the production while others did not. The production of antimicrobial activity is also dependent on growth temperature, with optimal production at 37°C. The antimicrobial activity was not restricted to streptococci, but effective against a variety of organisms, including ESKAPE pathogens. [ABSTRACT FROM AUTHOR]

There is a paucity of research regarding the role of endogenous cannabinoid signalling in adolescence on brain and behaviour development. We previously demonstrated effects of repeated CB1 receptor antagonism in adolescence on socioemotional behaviours and neural protein expression 24–48 h after the last drug administration in female rats, with no effect in males. Here we investigate whether greater effects would be manifested after a lengthier delay. In Experiment 1, male and female rats were administered either 1 mg / kg of the CB1 receptor-selective antagonist AM251, vehicle (VEH), or did not receive injections (NoINJ) daily on postnatal days (PND) 30–44 either alone (no adolescent confinement stress; noACS), or in tandem with 1 h ACS. On PND 70, adolescent AM251 exposure reduced anxiety in an elevated plus maze in males, irrespective of ACS, with no effects in females. On PND 73, there were no group differences in either sex in plasma corticosterone concentrations before or after 30 min of restraint stress, although injection stress resulted in higher baseline concentrations in males. Brains were collected on PND 74, with negligible effects of either AM251 or ACS on protein markers of synaptic plasticity and of the endocannabinoid system in the hippocampus and medial prefrontal cortex. In Experiment 2, rats from both sexes were treated with vehicle or AM251 on PND 30–44 and were tested for contextual fear conditioning and extinction in adulthood. AM251 females had greater fear recall than VEH females 24 h after conditioning, with no group differences in within- or between-session fear extinction. There were no group differences in long-term extinction memory, although AM251 females froze more during a reconditioning trial compared with VEH females. There were no group differences on any of the fear conditioning measures in males. Together, these findings indicate a modest, sex-specific role of CB1 receptor signalling in adolescence on anxiety-like behaviour in males and conditioned fear behaviour in females. [ABSTRACT FROM AUTHOR]

Abstract: Acyrthosiphon pisum is a polyphagous aphid of major importance on the pea crop to which few resistant cultivars are available. In this study, we screened a germplasm collection of Pisum spp. under field conditions over two seasons yielding the identification of a number of accessions with intermediate levels of resistance. Selected accessions were further studied under semi‐controlled and controlled conditions in no choice and choice assays to validate the responses, and to further characterise the mechanisms of resistance operative. Results elucidated the valuable resistance of accession P40 (Pisum sativum ssp. sativum) and P665 (P. sativum ssp. syriacum), with the combination of both antixenosis, by reducing aphid preference, and antibiosis, by diminishing aphid proliferation. [ABSTRACT FROM AUTHOR]

ABSTRACT: The breeding and non‐breeding ‘castes’ of eusocial insects provide a striking example of role‐specific selection, where each caste maximises fitness through different morphological, behavioural and physiological trait values. Typically, queens are long‐lived egg‐layers, while workers are short‐lived, largely sterile foragers. Remarkably, the two castes are nevertheless produced by the same genome. The existence of inter‐caste genetic correlations is a neglected consequence of this shared genome, potentially hindering the evolution of caste dimorphism: alleles that increase the productivity of queens may decrease the productivity of workers and vice versa, such that each caste is prevented from reaching optimal trait values. A likely consequence of this ‘intralocus caste antagonism’ should be the maintenance of genetic variation for fitness and maladaptation within castes (termed ‘caste load’), analogous to the result of intralocus sexual antagonism. The aim of this review is to create a research framework for understanding caste antagonism, drawing in part upon conceptual similarities with sexual antagonism. By reviewing both the social insect and sexual antagonism literature, we highlight the current empirical evidence for caste antagonism, discuss social systems of interest, how antagonism might be resolved, and challenges for future research. We also introduce the idea that sexual and caste antagonism could interact, creating a three‐way antagonism over gene expression. This includes unpacking the implications of haplodiploidy for the outcome of this complex interaction. [ABSTRACT FROM AUTHOR]

Abstract: Environmental factors, including temperature, can have large effects on species interactions, including mutualisms and antagonisms. Most insect species are infected with heritable bacterial symbionts with many protecting their hosts from natural enemies. However, many symbionts or their products are thermally sensitive; hence, their effectiveness may vary across a range of temperatures. In the pea aphid, Acyrthosiphon pisum, the bacterial symbiont Hamiltonella defensa and its associated APSE bacteriophages confer resistance to this aphid's dominant parasitoid, Aphidius ervi. Here, we investigate the effects of temperature on both endogenous and symbiont‐based protection against this parasitoid. We also explored the defensive properties of the X‐type symbiont, a bacterium hypothesized to shape aphid defence when co‐occurring with H. defensa. We show that H. defensa protection fails at higher temperatures, although some aphid genotype and H. defensa strain combinations are more robust than others at moderately warmer temperatures. We also found that a single X‐type strain neither defended against parasitism by A. ervi nor rescued lost H. defensa protection at higher temperatures. In contrast, endogenous aphid resistance was effective across temperatures, revealing that these distinct defensive modes are not equally robust to changing environments. Through a survey of field‐collected pea aphids, we found a negative correlation between H. defensa frequencies and average daily temperatures across North American locales, fitting expectations for reduced symbiont benefits under warm climates. Based on these findings, we propose that rising global temperatures could promote the widespread breakdown of defensive mutualisms, a prospect with implications for both human and ecosystem health. [ABSTRACT FROM AUTHOR]

The soilborne fungi Sclerotinia sclerotiorum, Rhizoctonia solani and the oomycete Pythium ultimum are among the most destructive pathogens for lettuce production. The application of the biocontrol agent Paenibacillus alvei K165 to the transplant soil plug of lettuce resulted in reduced S. sclerotiorum, R. solani and P. ultimum foliar symptoms and incidence compared to untreated controls, despite the suppressive effect of the pathogens on the rhizosphere population of K165. In vitro, K165 inhibited the growth of S. sclerotiorum and R. solani but not P. ultimum. Furthermore, the expression of the pathogenesis‐related (PR) gene PR1, a marker gene of salicylic acid (SA)‐dependent plant defence, and of the Lipoxygenase (LOX) and Ethylene response factor 1 (ERF1) genes, markers of ethylene/jasmonate (ET/JA)‐dependent plant defence was recorded. K165‐treated plants challenged with P. ultimum showed up‐regulation of PR1, whereas challenge with R. solani resulted in up‐regulation of LOX and ERF1, and challenge with S. sclerotiorum resulted in up‐regulation of PR1, LOX and ERF1. This suggests that K165 triggers the SA‐ and the ET/JA‐mediated induced systemic resistance against P. ultimum and R. solani, respectively, while the simultaneous activation of the SA and ET/JA signalling pathways is proposed for S. sclerotiorum. [ABSTRACT FROM AUTHOR]

Abstract: Trans‐AT polyketide synthases (PKSs) are a family of biosynthetically versatile modular type I PKSs that generate bioactive polyketides of impressive structural diversity. In this study, we detected, in the genome of several bacteria a cryptic, architecturally unusual trans‐AT PKS gene cluster which eluded automated PKS prediction. Genomic mining of one of these strains, the model methylotroph Methylobacterium extorquens AM1, revealed unique epoxide‐ and cyclopropanol‐containing polyketides named toblerols. Relative and absolute stereochemistry were determined by NMR experiments, chemical derivatization, and the comparison of CD data between the derivatized natural product and a synthesized model compound. Biosynthetic data suggest that the cyclopropanol moiety is generated by carbon–carbon shortening of a more extended precursor. Surprisingly, a knock‐out strain impaired in polyketide production showed strong inhibitory activity against other methylobacteria in contrast to the wild‐type producer. The activity was inhibited by complementation with toblerols, thus suggesting that these compounds modulate an as‐yet unknown methylobacterial antibiotic. [ABSTRACT FROM AUTHOR]

Abstract: This account mainly introduces and reviews our recent progress in three projects: antibacterial nanomaterial, electrocatalyst for detecting and electrode nanomaterial of energy storage device, especially the supercapacitor. Besides, our thought and idea about the design, fabrication and application of corresponding nanomaterials are sketched throughout the whole article in order to reveal the structure‐function relationship and corresponding mechanism. In the end, we tend to attach importance to the bottleneck of nanomaterial's development and put forward our understanding in this field. [ABSTRACT FROM AUTHOR]

The study was designed to investigate the involvement of noradrenergic and serotonergic receptor systems in the modulation of formalin-induced pain-related behaviour in the Speke's hinged tortoise. Intradermal injection of 100 μL of formalin at a dilution of 12.5% caused pain-related behaviour (hindlimb withdrawal) that lasted for a mean time of 19.28 min (monophasic response). Intrathecal administration of clonidine ( α2-adrenergic receptor agonist) and yohimbine ( α2-adrenergic receptor antagonist) at a dose of 40 μg/kg and 37.5 μg/kg or 50 μg/kg, respectively, caused a highly significant reduction in the duration of the formalin-induced pain-related behaviour. The effect of clonidine was reversed by intrathecal administration of yohimbine at a dose of 26.7 μg/kg. The effect of yohimbine at a dose of 50 μg/kg was reversed by intrathecal injection of 20 μg/kg of the serotonergic receptor antagonist methysergide maleate. When performing antagonistic reactions, the administration of the antagonist was followed immediately by that of the agonist. The study indicates that for experimental purposes, intrathecal route of drug administration through the atlanto-occipital joint is effective in tortoises. The data also suggest that testudines have noradrenergic and serotonergic systems that appear to play a role in the modulation of pain in this species. [ABSTRACT FROM AUTHOR]

Filamentous fungi from the genus Trichoderma are commonly found in soil. They are considered facultative mycoparasites, and are antagonists of other fungi such as the cultivar of leaf-cutting ants ( Leucoagaricus gongylophorus). The aim of the present study was to bioprospect Trichoderma spp. from different soils collected from Gurupi, Tocantins, Brazil, for antagonistic effects against the mutualistic fungus of leaf-cutting ants. To isolate filamentous fungi, samples were collected from six locations. Preliminarily, isolates were identified by morphological analysis as belonging to Trichoderma. Trichoderma spp. had their internal transcribed spacer region (ITS) of ribosomal RNA genes (rRNA) sequenced to confirm species-level taxonomy. L. gongylophorus was isolated from a laboratory ant colony. Antagonistic properties of seven isolates of Trichoderma against L. gongylophorus were measured using paired disks in Petri dishes with potato dextrose agar medium (PDA). All Trichoderma isolates inhibited the growth of L. gongylophorus in Petri dishes. Isolate 2 of Trichoderma spirale group exhibited slow mycelial growth in the Petri dish, and a high rate of inhibition against L. gongylophorus. This isolate is a promising fungus for field tests of biological control methods for leaf-cutting ants. [ABSTRACT FROM AUTHOR]

BACKGROUND Colorado potato beetle ( CPB) has become the biggest enemy of cultivated potato worldwide. One of the most effective sources of resistance to CPB is Solanum chacoense, an accession with a high leptine glycoalkaloid content. The aim of our study was to assay the repellence and toxicity of S. chacoense, its somatic hybrids ( SHs) and their backcross progenies ( BC1) with potato for CPB adults and larvae. Transgenic S. chacoense, deficient in DNA mismatch repair ( MMR), was also used to produce SHs, in order to increase homeologous recombination and hence introgression of wild-species DNA into the potato gene pool. RESULTS Wild-type SH was highly resistant to CPB. Resistance to CPB of BC1 progenies showed a 1:3 inheritance pattern. MMR-deficient SHs performed better in the resistance analysis. Most MMR-deficient SHs had a similar toxicity as S. chacoense and an intensely repellent effect on CPB adults. Resistance of SHs and BC1 clones may be attributed to leptine biosynthesis, which was confirmed using a RAPD marker. CONCLUSION This is the first report of SHs and their progenies exhibiting both antibiosis and antixenosis against CPB. Resistant SHs are an important step forward in combating this voracious pest of potato. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The popular perception of the history of antibiosis and penicillin is that Alexander Fleming was the sole researcher on penicillin. The literature, however, has documentation of preceding persons who reported definitively on these topics, from the late 19th century. Divergent reports on 'firsts' in the discovery of antimicrobial activity of Penicillium and on the use of penicillin as a therapeutic agent, are present. This review adds knowledge from diverse sources, and restores historical priorities to the conventional story of Penicillin. [ABSTRACT FROM AUTHOR]

Xanthomonas oryzae pv. oryzae ( Xoo) rapidly triggers a hypersensitive response (HR) and non-host resistance in its non-host plant Nicotiana benthamiana. Here, we report that Agrobacterium tumefaciens strain GV3101 blocks Xoo-induced HR in N. benthamiana when pre-infiltrated or co-infiltrated, but not when post-infiltrated at 4 h after Xoo inoculation. This suppression by A. tumefaciens is local and highly efficient to Xoo. The HR-inhibiting efficiency of A. tumefaciens is strain dependent. Strain C58C1 has almost no effect on Xoo-induced HR, whereas strains GV3101, EHA105 and LBA4404 nearly completely block HR formation. Intriguingly, these three HR-inhibiting strains employ different strategies to repress HR. Strain GV3101 displays strong antibiotic activity and thus suppresses Xoo growth. Comparison of the genotype and Xoo antibiosis activity of wild-type A. tumefaciens strain C58 and a set of C58-derived strains reveals that this Xoo antibiosis activity of A. tumefaciens is negatively, but not solely, regulated by the transferred-DNA (T-DNA) of the Ti plasmid pTiC58. Unlike GV3101, strains LBA4404 and EHA105 exhibit no significant antibiotic effect on Xoo, but rather abolish hydrogen peroxide accumulation. In addition, expression assays indicate that strains LBA4404 and EHA105 may inhibit Xoo-induced HR by suppression of the expression of Xoo type III secretion system (T3SS) effector genes hpa1 and hrpD6. Collectively, our results unveil the multiple levels of effects of A. tumefaciens on Xoo in N. benthamiana and provide insights into the molecular mechanisms underlying the bacterial antibiosis of A. tumefaciens and the non-host resistance induced by Xoo. [ABSTRACT FROM AUTHOR]