A Novel Structure Fusion Attention Model to Detect Architectural Distortion on Mammography.

Architectural distortion (AD) is one of the most common findings on mammograms, and it may represent not only cancer but also a lesion such as a radial scar that may have an associated cancer. AD accounts for 18-45% missed cancer, and the positive predictive value of AD is approximately 74.5%. Early detection of AD leads to early diagnosis and treatment of the cancer and improves the overall prognosis. However, detection of AD is a challenging task. In this work, we propose a new approach for detecting architectural distortion in mammography images by combining preprocessing methods and a novel structure fusion attention model. The proposed structure-focused weighted orientation preprocessing method is composed of the original image, the architecture enhancement map, and the weighted orientation map, highlighting suspicious AD locations. The proposed structure fusion attention model captures the information from different channels and outperforms other models in terms of false positives and top sensitivity, which refers to the maximum sensitivity that a model can achieve under the acceptance of the highest number of false positives, reaching 0.92 top sensitivity with only 0.6590 false positive per image. The findings suggest that the combination of preprocessing methods and a novel network architecture can lead to more accurate and reliable AD detection. Overall, the proposed approach offers a novel perspective on detecting ADs, and we believe that our method can be applied to clinical settings in the future, assisting radiologists in the early detection of ADs from mammography, ultimately leading to early treatment of breast cancer patients.

The biocontrol potentials of rhizospheric bacterium Bacillus velezensis K0T24 against mulberry bacterial wilt disease.

Mulberry bacterial wilt disease, caused by Ralstonia pseudosolanacearum, is a devastating soil-borne disease in the silk-mulberry-related industry. In this study, through high-throughput sequencing, we compared the rhizosphere bacterial composition of the mulberry-resistant cultivar (K10) and susceptible cultivar (G12), confirming Bacillus as a genus-level biomarker for K10. Next, twelve Bacillus spp. isolates, derived from the rhizosphere of K10, were screened for their antagonistic activity against R. pseudosolanacearum. The isolate showing strong antagonism was identified as B. velezensis K0T24 and selected for further analysis. The fermentation supernatant of B. velezensis K0T24 significantly inhibited the growth of R. pseudosolanacearum (82.47%) and the expression of its pathogenic genes. Using B. velezensis K0T24 in mulberry seedlings also increased defense enzyme activities and achieved a control efficacy of up to 55.17% against mulberry bacterial wilt disease. Collectively, our findings demonstrate the potential of B. velezensis K0T24 in suppressing mulberry bacterial wilt disease.

Rational Design of Vinylene Carbonate-Inspired 1,3-Dimethyl-1H-imidazol-2(3H)-one Additives to Stabilize High-Voltage Lithium Metal Batteries.

Lithium metal batteries (LMBs) employing high-voltage nickel-rich cathodes represent a promising strategy to enable higher energy density storage systems. However, instability at the electrolyte-electrode interfaces (EEIs) currently impedes the translation of these advanced systems into practical applications. Herein, 1,3-dimethyl-1H-imidazol-2(3H)-one (DMIO), integrating structural features of vinylene carbonate (VC) while substituting oxygen with electron-donating nitrogen, has been synthesized and validated as a multifunctional electrolyte additive for high-voltage LMBs. Theoretical calculations and experimental results demonstrate that the potent electron-donating nitrogen in DMIO enables preferential DMIO oxidation at the cathode while preserving its carbon-carbon double bond for a concomitant reduction on the anode. Thereby, robust DMIO-derived EEIs are generated, reinforcing cycling in the full cells. Additionally, DMIO leverages Lewis acid-based interactions to coordinate and sequester protons from acidic LiPF6 decomposition byproducts, concurrently retarding LiPF6 hydrolysis while attenuating parasitic consumption of EEIs by acidic species. Consequently, incorporating DMIO into conventional carbonate electrolytes enables an improved capacity retention of Li||NCM622 cells to 81% versus 26% in the baseline electrolyte after 600 cycles. Similarly, DMIO improves Li anode cycling performance, displaying extended life spans over 200 h in Li||Li symmetric cells and enhancing Coulombic efficiency from 76% to 88% in Li||Cu cells. The synergistic effects of DMIO on both the cathode and anode lead to substantially improved cell lifetime. This rationally designed, multifunctional electrolyte additive paradigm provides vital insights that can be translatable to further electrolyte molecular engineering strategies.

Acid-Promoted Cyclization of α-Azidobenzyl Ketones through C═N Bond Formation: Synthesis of 6-Substituted Quinoline Derivatives.

An acid-promoted cyclization of α-azidobenzyl ketones has been developed for the synthesis of 6-substituted quinoline derivatives. A variety of synthetically useful 6-OTf or -OMs quinoline derivatives were obtained in moderate to good yields. The reaction proceeds via C═N bond formation without organophosphine, providing convenient access to structurally interesting and synthetically important 6-substituted quinoline derivatives in moderate to good yields. A mechanistic perspective that is different from the traditional intramolecular Schmidt reaction has been proposed.

A Green Asymmetric Bicyclic Co-Solvent Molecule for High-Voltage Aqueous Lithium-Ion Batteries.

Hybridizing aqueous electrolytes with organic co-solvents can effectively expand the voltage window of aqueous electrolytes while reducing salt usage, but most reported co-solvents are usually flammable and toxic, hardly achieving compatibility between safety and electrochemical performance. Here, a new non-flammable and non-toxic low-salt-concentration (1.85 m) aqueous electrolyte is reported using the green co-solvent isosorbide dimethyl ether (IDE). Owing to its unique 3D molecular structure, IDE can form a five-membered ring structure by binding the Li ion. The steric hindrance effect from IDE weakens its solvation ability, generating anion-participated solvation structures that produce a robust and uniform LiF-rich solid electrolyte interphase layer while containing elastic IDE-derived organics. Moreover, the multiple O atoms in IDE can effectively regulate the intermolecular hydrogen bonding networks, reducing H2O molecule activity and expanding the electrochemical window. Such unique solvation structures and optimized hydrogen bonding networks enabled by IDE effectively suppress electrode/electrolyte interfacial side reactions, achieving a 4.3 V voltage window. The as-developed Li4Ti5O12(LTO)||LiMn2O4(LMO) full cell delivers outstanding cycling performance over 450 cycles at 2 C. The proposed green hybrid aqueous electrolyte provides a new pathway for developing high-voltage aqueous lithium batteries.

Atmospheric Chemistry of NH2SO3H in Polluted Areas: An Unexpected Isomerization of NH2SO3H in Acid-Polluted Regions.

NH2SO3H is an effective nucleation agent for the formation of atmospheric aerosols and cloud particles. So, the ammonolysis of SO3 to form NH2SO3H without and with neutral (H2O) and basic (NH3) trace gases has been extensively investigated. However, the acidic trace gas X (X = H2SO4 and CH3SO3H)-assisted ammonolysis of SO3 is still up for debate. In this work, a comprehensive theoretical investigation of X-assisted ammonolysis of SO3 and its reverse reaction (the isomerization of NH2SO3H to form SO3-···NH3+) was carried out in the gas phase and at the air-water interface. The gas-phase results show that X-assisted isomerization of NH2SO3H to form SO3-···NH3+ is more energetically and kinetically favorable than its reverse reaction and the isomerization of NH2SO3H in the presence of H2O and NH3. Such unexpected findings revealed that gas-phase NH2SO3H is highly reactive in the presence of acidic trace gas in contrast to the high stability of NH2SO3H in neutral and basic conditions. At the air-water interface, the X-assisted isomerization reaction of NH2SO3H involves multiple water molecules. The loop structure of the reaction center (X···NH2SO3H···3H2O) promotes the transfer of protons in the water molecules to form the SO3-···NH3+ ion pair, which can then interact with several interfacial water molecules to form ammonium bisulfate. These interfacial reaction channels follow a stepwise mechanism and proceed at the picosecond time-scale. The findings of this study will contribute to a better understanding of the atmospheric behavior of NH2SO3H in polluted acidic trace gases.

An Interview Study of College Students' Health Emergency Literacy in the Context of COVID-19 Normalized Prevention and Control.

Objective: To explore the changes in college students' awareness of health protection under the normalization of COVID-19, and to seek its connection with the epidemic management in colleges and universities, so as to provide reference information for continuous health education activities and the cultivation of college students' health emergency literacy in colleges and universities. Methods: Qualitative interviews were used to understand the extent of health emergency literacy among college students enrolled in the context of a normalized epidemic and the factors associated with it that cause changes around a question outline. Results: The interviewees generally had a lax mentality in the late stage of the interview, the importance they attached to epidemic prevention and control decreased significantly, and the way to know about epidemic protection measures and other knowledge was mainly through the mass news media. All respondents affirm the importance of social software for outbreak prevention and control. All 17 interviewees were able to mention basic outbreak protection methods, but 15 of them showed inconsistent behavior in words and actions later. Conclusion: The vast majority of respondents' health emergency literacy appears to weaken in the late stages of epidemic normalization, and the effect of traditional approaches used by universities to improve college students' health emergency literacy is weak.

Study on the Potential for Stimulating Mulberry Growth and Drought Tolerance of Plant Growth-Promoting Fungi.

Drought stress often leads to heavy losses in mulberry planting, especially for fruits and leaves. Application of plant growth-promoting fungi (PGPF) endows various plant beneficial traits to overcome adverse environmental conditions, but little is known about the effects on mulberry under drought stress. In the present study, we isolated 64 fungi from well-growing mulberry trees surviving periodical drought stress, and Talaromyces sp. GS1, Pseudeurotium sp. GRs12, Penicillium sp. GR19, and Trichoderma sp. GR21 were screened out due to their strong potential in plant growth promotion. Co-cultivation assay revealed that PGPF stimulated mulberry growth, exhibiting increased biomass and length of stems and roots. Exogenous application of PGPF could alter fungal community structures in the rhizosphere soils, wherein Talaromyces was obviously enhanced after inoculation of Talaromyces sp. GS1, and Peziza was increased in the other treatments. Moreover, PGPF could promote iron and phosphorus absorption of mulberry as well. Additionally, the mixed suspensions of PGPF induced the production of catalase, soluble sugar, and chlorophyll, which in turn enhanced the drought tolerance of mulberry and accelerated their growth recovery after drought. Collectively, these findings might provide new insights into improving mulberry drought tolerance and further boosting mulberry fruit yields by exploiting interactions between hosts and PGPF.

Afatinib triggers a Ni2+ -resistant Ca2+ influx pathway in A549 non-small cell lung cancer cells.

Afatinib is used to treat non-small cell lung cancer cells (NSCLC), and its mechanism involves irreversible inhibition of epidermal growth factor receptor (EGFR) tyrosine kinase. In this study, we examined if afatinib had cytotoxic action against NSCLC other than inhibition of tyrosine kinase. Afatinib (1-30 µM) caused apoptotic death in A549 NSCLC in a concentration-dependent manner. Afatinib triggered Ca2+ influx without causing Ca2+ release, and the Ca2+ influx was unaffected by sodium orthovanadate (SOV, an inhibitor of tyrosine phosphatase), suggesting that afatinib-triggered Ca2+ response was unrelated to its inhibition of tyrosine kinase. Addition of afatinib also promoted Mn2+ influx. Ca2+ influx triggered by afatinib was resistant to SKF96365 and ruthenium red (two general blockers of TRP channels) and, unexpectedly, Ni2+ (a non-specific Ca2+ channel blocker). Afatinib caused an increase in mitochondrial Ca2+ level, an initial mitochondrial hyperpolarization (4 h) and followed by mitochondrial potential collapse (24-48 h). Afatinib-induced cell death was slightly but significantly alleviated in low extracellular Ca2+ condition or under pharmacological block of mitochondrial permeability transition pore (MPTP) opening by cyclosporin A. Therefore, in addition to tyrosine kinase inhibition as a major anti-cancer mechanism of afatinib, stimulation of an atypical Ca2+ influx pathway, mitochondrial Ca2+ overload, and potential collapse in part contribute to afatinib-induced cell death.

Prevalence and risk factors of metabolic syndrome among adults in Hainan Province / 中国热带医学

@#Abstract: Objective　This study aims to explore the prevalence and risk factors of metabolic syndrome (MS) among the adults in Hainan Province, and to provide scientific basis for MS prevention and control. Methods　A multi-stage cluster random sampling method was applied to select 3 690 permanent residents aged 18 years and above in Hainan Province. The survey was conducted by trained investigators using household appointments and centralized surveys. A questionnaire survey, physical measurement, and laboratory examination were conducted after the collection of blood samples. The processed samples were then tested by a quality-controlled laboratory. Finally, we analysed the prevalence of metabolic syndrome (MS) and its relationship with population characteristics and health-related behaviors. Results　The crude prevalence of MS in the population aged 18 and above in Hainan province was 19.46% and the standardized prevalence was 13.21%, with a higher rate in urban areas (22.21%) than in rural areas (18.13%). The prevalence of MS increased with age (P<0.001), and there were significant differences in MS prevalence among different marital and occupational statuses (P<0.01). Logistic regression results indicated that the age groups of 40-<50 years (OR=2.986, 95%CI:1.355-6.580), 50-<60 years (OR=3.739, 95%CI: 1.715-8.151), 60-<70 years (OR=3.890, 95%CI: 1.769-8.556), 70 years and above (OR=3.927, 95%CI: 1.758-8.771), technical, transportation and production personnel (OR=1.579, 95%CI: 1.033-2.412), retired (OR=1.788, 95%CI: 1.415-2.259), unemployed (OR=1.503, 95%CI: 1.044-2.165), smoking cessation (OR=1.582, 95%CI: 1.162-2.154), insufficient intake of fruits and vegetables (OR=1.196, 95%CI: 1.005-1.422), and insufficient physical activity (OR=1.437, 95%CI: 1.155-1.787) were all associated with the prevalence of MS. Among the investigated subjects, 30.22% of them had one abnormal component, with hyperglycemia being the highest (54.44%); 24.25% of them had two abnormal components, with "hyperglycemia + hypertension" being the highest (33.30%); and 19.46% had three or more components, with "overweight/obesity + hyperglycemia + hypertension" being the highest (24.79%). Conclusions　The prevalence of MS in Hainan Province is on the rise, and effective lifestyle intervention measures are needed to reduce the risk of MS.

Endophytic Klebsiella aerogenes HGG15 stimulates mulberry growth in hydro-fluctuation belt and the potential mechanisms as revealed by microbiome and metabolomics.

Growth promotion and stress tolerance induced by endophytes have been observed in various plants, but their effects on mulberry regularly suffering flood in the hydro-fluctuation belt are less understood. In the present study, endophytic Klebsiella aerogenes HGG15 was screened out from 28 plant growth promotion (PGP) bacteria as having superior PGP traits in vitro and in planta as well as biosafety for silkworms. K. aerogenes HGG15 could actively colonize into roots of mulberry and subsequently transferred to stems and leaves. The 16S ribosomal RNA (V3-V4 variable regions) amplicon sequencing revealed that exogenous application of K. aerogenes HGG15 altered the bacterial community structures of mulberry roots and stems. Moreover, the genus of Klebsiella was particularly enriched in inoculated mulberry roots and was positively correlated with mulberry development and soil potassium content. Untargeted metabolic profiles uncovered 201 differentially abundant metabolites (DEMs) between inoculated and control mulberry, with lipids and organo-heterocyclic compounds being particularly abundant DEMs. In addition, a high abundance of abiotic stress response factors and promotion growth stimulators such as glycerolipid, sphingolipid, indole, pyridine, and coumarin were observed in inoculated mulberry. Collectively, the knowledge gained from this study sheds light on potential strategies to enhance mulberry growth in hydro-fluctuation belt, and microbiome and metabolite analyses provide new insights into the growth promotion mechanisms used by plant-associated bacteria.

Role of Rhizospheric Bacillus megaterium HGS7 in Maintaining Mulberry Growth Under Extremely Abiotic Stress in Hydro-Fluctuation Belt of Three Gorges Reservoir.

Plant growth-promoting rhizobacteria have been shown to play important roles in maintaining host fitness under periods of abiotic stress, and yet their effect on mulberry trees which regularly suffer drought after flooding in the hydro-fluctuation belt of the Three Gorges Reservoir Region in China remains largely uncharacterized. In the present study, 74 bacterial isolates were obtained from the rhizosphere soil of mulberry after drought stress, including 12 phosphate-solubilizing and 10 indole-3-acetic-acid-producing isolates. Bacillus megaterium HGS7 was selected for further study due to the abundance of traits that might benefit plants. Genomic analysis revealed that strain HGS7 possessed multiple genes that contributed to plant growth promotion, stress tolerance enhancement, and antimicrobial compound production. B. megaterium HGS7 consistently exhibited antagonistic activity against phytopathogens and strong tolerance to abiotic stress in vitro. Moreover, this strain stimulated mulberry seed germination and seedling growth. It may also induce the production of proline and antioxidant enzymes in mulberry trees to enhance drought tolerance and accelerate growth recovery after drought stress. The knowledge of the interactions between rhizobacteria HGS7 and its host plant might provide a potential strategy to enhance the drought tolerance of mulberry trees in a hydro-fluctuation belt.

Liraglutide Plus Dapagliflozin for High Uric Acid and Microalbuminuria in Diabetes Mellitus Complicated With Metabolic Syndrome.

Context: Diabetes mellitus (DM) represents an emerging epidemic, poses serious threats to human health, and can seriously compromise patients' quality of life (QoL). Currently, no cure exists for DM. Some studies have found that both liraglutide and dapagliflozin have great therapeutic potential in preventing and treating DM and its complications. Objective: The study aimed to examine the impact of liraglutide plus dapagliflozin on high uric acid (UA) and microalbuminuria (MAU) in patients with diabetes mellitus (DM) complicated with metabolic syndrome (MS). Design: The research team designed a randomized controlled trial. Setting: The study took place at the Second Affiliated Hospital of Nanjing Medical University in Nanjing, Jiangsu, China. Participants: Participants were 125 patients with DM complicated with MS who were treated in the outpatient clinic of the endocrinology department at the hospital between January 1, 2020 and December 31, 2021, with 68 in the intervention group and 57 in the control group. Intervention: The intervention and control groups both received 0.6 mg of liraglutide. The intervention group also received 5 mg of dapagliflozin once a day. The dosages were increased at one week after baseline based on the participant's condition. Outcome Measures: Therapeutic effects, glycolipid metabolism, inflammation, uric acid (UA), microalbuminuria (MAU), cardiac function, and quality of life (QoL) were compared between the two groups. Results: Postintervention, the clinical efficacy was significantly higher in the intervention group than in the control group. The intervention group had significantly lower glycolipid metabolism and inflammatory-factor levels than the control group UA and MAU had declined in both groups but were significantly lower in the intervention group. The left ventricular ejection fraction (LVEF) increased and the left ventricular end diastolic diameter (LVEDd) decreased in both groups, but the intervention group had significantly greater changes as compared with those in the control group. The intervention group was also superior to the control group in patients' QoL. Conclusions: Liraglutide plus dapagliflozin has highly therapeutic effect for patients with DM complicated with MS and can effectively reduce UA and MAU levels. The current research team will launch a more comprehensive analysis as soon as possible to obtain the most accurate results.

Li-N Interaction Induced Deep Eutectic Gel Polymer Electrolyte for High Performance Lithium-Metal Batteries.

As emerging eutectic mixtures, deep eutectic electrolytes (DEEs) show unique properties for Li-metal batteries (LMBs). However, the limited choice and inferior electrode compatibility hinder their further development in LMBs. Herein, we report a new 1,2-dimethylimidazole (DMIm)-based deep eutectic gel polymer electrolyte induced by Li-N interaction. We demonstrate that incorporating electron-withdrawing polyvinylidene difluoride (PVDF) polymer into the DMIm-based DEE changes the coordination environment of Li+ ions, leading to a high transference number of Li+ ions (0.65) and superior interface stability between the electrolyte and Li anode. The deep eutectic gel polymer electrolyte exhibits excellent non-flammability, high ionic conductivity (1.67 mS cm-1 at 30 °C), and high oxidation voltage (up to 4.35 V vs. Li/Li+ ). The Li||LFP cell based on the newly developed deep eutectic gel polymer electrolyte can achieve superior long-term cycling stability at a wide range of rates.

Mycoplasma pneumonia Infection Is Associated With an Increased Risk of Systemic Lupus Erythematosus: A Nationwide, Retrospective Cohort Study.

Background: Infections may play a role in the development of systemic lupus erythematosus (SLE). Objective: To assess the link between Mycoplasma pneumonia (M. pneumonia) infection and the incidence of SLE. Method: We conducted a retrospective cohort study, which identified 116,043 hospitalized patients with M. pneumoniae between 2000 and 2012 from the Taiwan National Health Insurance Research Database and compared them with 447,839 matched inpatients who had never been diagnosed with M. pneumonia infection (at a 1:4 ratio, matched by age, gender, and index year). Their comparative risk of developing SLE was evaluated. The follow-up period was defined as the time from the initial diagnosis of M. pneumonia infection to the date of SLE diagnosis, or December 31, 2013. The incidence rates of SLE were assessed in people with and without M. pneumoniae infection. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs), with the uninfected group used as the reference. Results: The adjusted HR of SLE for the M. pneumoniae group was 2.97 with 95% CI = 2.18-4.05 compared with the uninfected group. The risk was most significantly higher within 0.5 years after the M. pneumoniae infection with an adjusted HR of 6.18 (95% CI = 3.82-9.97, p < 0.01). The adjusted HR for SLE from 0.5 to 2 years and from 2 to 5 years after M. pneumoniae infection was 1.59 (95% CI = 0.70-3.59, p = 0.27) and 2.42 (95% CI = 1.22-4.81, p = 0.01), respectively. Conclusion: The incidence of SLE was significantly higher in subjects infected with M. pneumoniae.

Plasmonic Gold Nanomaterials as Photoacoustic Signal Resonant Enhancers for Cysteine Detection.

The development of photoacoustic systems is important for the real-time detection of cysteine (Cys), a biothiol in biological systems that serves as a significant biomarker for human health. Advanced photoacoustic (PA) signals with colloidal plasmonic Au nanomaterials rely on the efficient conversion of light to energy waves under moderately pulsed laser irradiation. In this study, we synthesized Cys-capped Au nanorods (Au@Cys NRs) and Cys-capped Au nanoparticles (Au@Cys NPs) through a conjugate of three Cys concentrations (10, 100, and 1000 µM). These plasmonic Au nanomaterials can be used as a PA resonance reagent due to their maximum localized surface plasmon resonance (LSPR) absorption bands at 650 nm and 520 nm in Au NRs and Au NPs, respectively. Subsequently, the PA signals were noticeably increased proportionally to the concentrations in the Au@Cys NRs and Au@Cys NPs under 658 nm and 520 nm laser irradiation, respectively, according to our portable photoacoustic system. Furthermore, PA signal amplitudes in Cys detection are boosted by ~233.01% with Au@Cys NRs and ~102.84% with Au@Cys NPs enhancement, compared to free Cys, according to ultrasound transducers at frequencies of 3 MHz.

The impact of the endophytic bacterial community on mulberry tree growth in the Three Gorges Reservoir ecosystem, China.

Plant-associated microbes influence plant performance and may also impact biotic and abiotic stress tolerance. The microbiome of mulberry trees planted for ecological restoration in the hydro-fluctuation belt of the Three Gorges Reservoir Region, China, exhibited distinct patterns of localization. The endosphere exhibited lower α-diversity relative to the rhizosphere, but was more closely related to host growth status, especially in stem tissues. Pantoea was the predominant bacterial genus inhabiting the stems of two well-growing plants, while sequences identified as Pseudomonas and Pantoea were abundant in poorly growing plants. The complexity of the endophytic community was more connected to growth status in well-growing plants than it was in poorly growing plants. Among 151 endophytes cultured from collected samples of mulberry, 64 exhibited plant growth-promoting (PGP) potential in vitro and the majority of beneficial taxa were harvested from well-growing plants. Collectively, the present study indicates that the recruitment of beneficial endophytes may contribute to mulberry fitness under abiotic stress, and it provides a foundation for the development of a new strategy in vegetation restoration.

An Efficient and Stable Perovskite Solar Cell with Suppressed Defects by Employing Dithizone as a Lead Indicator.

The defects in perovskite films are one of the most non-negligible factors that can attenuate the performances of perovskite solar cell. This work fabricates defect-reduced perovskite film by using the lead indicator (dithizone) as an additive of perovskite functional layer. The dithizone can retard the crystallization rate of perovskite films, passivate the defects, and enhance the structure stability of perovskite by coordinating with lead atoms. As a result, the device doped with dithizone yields outstanding power conversion efficiency and stability.

Diversity of cultivable endophytic bacteria in mulberry and their potential for antimicrobial and plant growth-promoting activities.

Endophytic bacteria-based biocontrol is regarded as a potential plant disease management strategy. Present study analyzed the diversity of mulberry endophytic bacteria basing on a culture-dependent approach and further evaluated their antimicrobial and plant growth-promoting (PGP) activities. A total of 608 cultivable endophytic bacteria, belonging to 4 phyla and 36 genera, were isolated from four mulberry cultivars having different resistance to sclerotiniosis in three seasons. Taxonomic compositional analysis results showed that Proteobacteria, Firmicutes, and Actinobacteria were the three dominant bacterial phyla in all communities, with the representative genera Pantoea, Bacillus, Pseudomonas, Curtobacterium, and Sphingomonas. Diversity analysis results indicated that the diversity of winter community was higher than that of spring or autumn, and higher diversities were detected in the resistant cultivar communities compared with the susceptible cultivar. Antagonism assays results showed that 33 isolates exhibited strong and stable activity against three phytopathogens which are Sclerotinia sclerotiorum, Botrytis cinerea, and Colletotrichum gloeosporioide. Eight endophytic bacteria were selected out from 33 antagonists based on the evaluation of antagonistic and PGP activities. Furthermore, pot experiment results revealed that all the 8 tested endophytes stimulated the growth of mulberry seedlings at different levels, and Bacillus sp. CW16-5 exhibited the highest promotion capacity, which the shoot length and the root fresh weight were increased by 83.37% and 217.70%, respectively. Altogether, present study revealed that mulberry harbors a large amount of diverse cultivable endophytic bacteria and they also serve as novel sources of beneficial bacteria and bioactive metabolites.

A Microbiome Study Reveals Seasonal Variation in Endophytic Bacteria Among different Mulberry Cultivars.

Knowledge of seasonal shifts in the bacterial community composition among different mulberry (Morus L.) cultivars will facilitate to develop the biocontrol phytopathogens strategy using endophytic bacteria. The present study investigated the endophytic bacterial communities of four mulberry cultivars that have different resistance to mulberry fruit sclerotiniosis using Illumina-based sequencing of the 16S rRNA gene fragment in spring and autumn. The results indicated that spring samples harbor higher bacterial operational taxonomic units (OTUs), α-diversity, and bacterial community complexity in comparison with autumn samples. The taxonomic composition analysis showed that the majority of endophytes were composed of Proteobacteria (genus level: Methylobaterium) and Actinobacteria in spring, while sequences classified as Proteobacteria (genus level: Pantoea and Pseudomonas) were abundant in autumn. Analysis of ß-diversity also revealed endophytic bacteria were divided into two main groups by season. By comparison among different mulberry cultivars, we found that Pantoea, Methylobaterium, and Pseudomonas were the three major bacterial genera in all cultivars, while their relative abundances varied with cultivars and appeared no obvious relationship with resistance level of mulberry fruit sclerotiniosis. The complex correlation of the endophytic communities in susceptible mulberry cultivars was higher than that of the resistant cultivars. Overall, the findings suggested that season plays a key role in determining the mulberry endophytic bacterial communities, followed by host cultivar, and Proteobacteria was the predominant phylum in both seasons and different mulberry cultivars.