Ralstonia solanacearum type III effector RipAF1 mediates plant resistance signaling by ADP-ribosylation of host FBN1.

Ralstonia solanacearum (Rso) causes destructive bacterial wilt across a broad range of host plants by delivering a repertoire of type III effectors. In the present study, we determined that the deletion of the type III effector RipAF1 resulted in increased virulence on Nicotiana benthamiana, Solanum lycopersicum, and Capsicum annuum plants. RipAF1 showed ADP-ribosylation activity in vivo and in vitro. Transient overexpression of RipAF1 suppressed jasmonic acid (JA) signaling and induced salicylic acid (SA) signaling. The ADP-ribosylation activity of RipAF1 was essential for JA and SA signaling mediation. Host fibrillin FBN1 was identified as a RipAF1-interactor that is ADP-ribosylated by RipAF1 directly. Most importantly, the ADP-ribosylation of conserved residues of FBN1 contributes to its localization to the plasma membrane and leads to the suppression of JA signaling and induction of SA signaling. We concluded that RipAF1 mediates antagonistic crosstalk between JA and SA signaling pathways by ADP-ribosylation of FBN1.

Xanthomonas citri subsp. citri type III effector PthA4 directs the dynamical expression of a putative citrus carbohydrate-binding protein gene for canker formation.

Xanthomonas citri subsp. citri (Xcc), the causal agent of citrus canker, elicits canker symptoms in citrus plants because of the transcriptional activator-like (TAL) effector PthA4, which activates the expression of the citrus susceptibility gene CsLOB1. This study reports the regulation of the putative carbohydrate-binding protein gene Cs9g12620 by PthA4-mediated induction of CsLOB1 during Xcc infection. We found that the transcription of Cs9g12620 was induced by infection with Xcc in a PthA4-dependent manner. Even though it specifically bound to a putative TAL effector-binding element in the Cs9g12620 promoter, PthA4 exerted a suppressive effect on the promoter activity. In contrast, CsLOB1 bound to the Cs9g12620 promoter to activate its expression. The silencing of CsLOB1 significantly reduced the level of expression of Cs9g12620, which demonstrated that Cs9g12620 was directly regulated by CsLOB1. Intriguingly, PhtA4 interacted with CsLOB1 and exerted feedback control that suppressed the induction of expression of Cs9g12620 by CsLOB1. Transient overexpression and gene silencing revealed that Cs9g12620 was required for the optimal development of canker symptoms. These results support the hypothesis that the expression of Cs9g12620 is dynamically directed by PthA4 for canker formation through the PthA4-mediated induction of CsLOB1.

Restricted health service utilization and subsequent positive self-care behavior during the early COVID-19 pandemic in China.

Background: The reallocation of health resources, epidemic prevention and control measures during the COVID-19 pandemic triggered widespread restricted health service utilization, some residents and patients tried positive self-care behavior to maintain their health, yet the efficacy of this intervention remains unclear. Object: Based on the reasoned action approach (RAA) theory, this study aimed to investigate the correlation between self-care behavior and restricted health service utilization among adults in China, trying to discover the vulnerable groups and external and intrinsic factors that affect self-care behavior among Chinese adults. Methods: Data on demographics, socioeconomic, health status, and self-care behavior were collected in "The Early China COVID-19 Survey," a cross-sectional anonymous online survey of the general population in China. Self-care behavior was measured by four indicators: weight control (WC), physical activity (PA), prevention behavior (PB), and online medical consultation (OMC). The multiple linear models and binary logistic regression were used to examine whether restricted health service utilization (RHSU) is associated with self-care behaviors; also, adjusted multivariate logistic regression was used to analyze subgroup heterogeneity. Results: In total, 8,428 adult participants completed the survey, the mean OMC score was 1.51 (SD 1.34), the mean PB score was 18.17 (SD 3.44), and the proportion of participants who engaged in WC and PA was 42.30 and 62.57%, respectively. According to the multiple regression model, the RHSU was significantly positively correlated with all four indicators of self-care (WC: OR = 1.34, p < 0.001, PA: OR = 1.34, p < 0.05, MC: OR = 1.30, p < 0.001, PB: coef = 0.16, p < 0.05). We also observed some significant differences in the intensity of this relationship by subgroup analysis, precisely, OMC (high vs. moderate vs. low infection-risk level: OR = 1.48; 1.41; 1.19, p < 0.1), PA (male vs. female: OR = 1.27;1.06; p < 0.05, high vs. Moderate and low infection-risk level: OR = 1.51; 1.17; 1.02, p < 0.05), PB (Chronic disease groups vs. no: coef = 0.46; 0.1, p < 0.05). Conclusion: Restricted health service utilization predicts more positive self-care behavior, and the intensity of partial correlation was significantly different in the subgroups of sex, actual infection risk level of the living area, and chronic diseases. These findings highlight the urgent demand for self-care behavior among Chinese adults during the pandemic and provide new insights for developing self-care and reducing the burden on the healthcare system in the long term.

Identification of the function of a key gene NnHCT1 in lignin synthesis in petioles of Nelumbo nucifera.

Leaf petiole or stem strength is an important agronomic trait affecting the growth of underground organs as a channel for material exchange and plays a vital role in the quality and yield of crops and vegetables. There are two different types of petioles in lotus, floating leaf petioles and vertical leaf petioles; however, the internal difference mechanism between these petioles is unclear. In this study, we investigated the differences between the initial vertical leaf petioles and the initial floating leaf petioles based on RNA sequencing (RNA-seq), and >2858 differentially expressed genes were annotated. These genes were chiefly enriched in phenylpropanoid biosynthesis, which is the source of the lignin and cellulose in petioles and stems. Lignin biology-related gene NnHCT1 was identified, and subsequent biological function validation demonstrated that the transient overexpression of NnHCT1 significantly increased the lignin and cellulose contents in lotus petioles and tobacco leaves. In contrast, silencing NnHCT1 through virus-induced gene silencing significantly reduced petiole lignin synthesis. Additionally, differentially up-regulated MYB family transcription factors were identified using RNA-seq. Yeast-one-hybrid and dual-luciferase reporter assays demonstrated that MYB4 could bind to the NnHCT1 promoter and up-regulate NnHCT1 expression. These findings demonstrate the significant potential of NnHCT1 to enhance lignin synthesis, thereby improving stem or petiole resistance to stunting and explaining the need for the study of differential petiole relationships in plants.

Association between a metabolic score for insulin resistance and hypertension: results from National Health and Nutrition Examination Survey 2007-2016 analyses.

Background: The Metabolic Score for Insulin Resistance (METS-IR) offers a promising and reliable non-insulin-based approach to assess insulin resistance and evaluate cardiometabolic risk. However, evidence for the association between METS-IR and hypertension was still limited. Methods: Participants from the National Health and Nutrition Examination Survey (NHANES) database from 2007-2016 were selected for weighted multivariable regression analyses, subgroup analyses and restricted cubic spline (RCS) modeling to assess the association between the METS-IR and hypertension, as well as systolic blood pressure (SBP) and diastolic blood pressure (DBP). Results: This study enrolled 7,721 adults aged ≥20 years, 2,926 (34.03%) of whom was diagnosed as hypertension. After adjusting for all potential covariates, an increased METS-IR (log2 conversion, denoted as log2METS-IR) was independently associated with a higher prevalence of hypertension (odd ratio [OR] 3.99, 95% confidence interval [CI] 3.19~5.01). The OR for hypertension in subjects with the highest quartile of METS-IR was 3.89-fold (OR 3.89, 95% CI 3.06~4.94) higher than that in those with the lowest quartile of METS-IR. This positive correlation became more significant as METS-IR increased (p for trend < 0.001). Log2METS-IR was significantly correlated with increase in SBP (ß 6.75, 95% CI 5.65~7.85) and DBP (ß 5.59, 95% CI 4.75~6.43) in a fully adjusted model. Consistent results were obtained in subgroup analyses. Hypertension, SBP and DBP all exhibited a non-linear increase with the rise in METS-IR. The minimal threshold for the beneficial association of METS-IR with hypertension, SBP and DBP were all identified to be 46.88. Conclusion: The findings of this study revealed a significant positive association between METS-IR and hypertension among US adults, suggesting METS-IR as a potential tool for assessing hypertension risk.

Decomposition analysis on the equity of health examination utilization for the middle-aged and elderly people in China: based on longitudinal CHARLS data from 2011 to 2018.

BACKGROUND: This study aimed to investigate the utilization rate and equity of health examination service among the middle-aged and elderly population in China from 2011 to 2018. The contribution of various determinants to the inequity in health examination service utilization was also examined. METHODS: Data from the China Health and Retirement Longitudinal Survey (CHARLS) were analyzed to assess the health examination service utilization rate among the middle-aged and elderly population. A concentration curve and concentration index were employed to measure the equity of health examination service utilization and decomposed into its determining factors. Horizontal inequity index was applied to evaluate the trends in equity of health examination service. RESULTS: The health examination service utilization rates among the middle-aged and elderly population were 29.45%, 20.69%, 25.40%, and 32.05% in 2011, 2013, 2015, and 2018, respectively. The concentration indexes for health examination service utilization were 0.0080 (95% CI: - 0.0084, 0.0244), 0.0155 (95% CI: - 0.0054, 0.0363), 0.0095 (95% CI: - 0.0088, 0.0277), and - 0.0100 (95% CI: - 0.0254, 0.0054) from 2011 to 2018, respectively. The horizontal inequity index was positive from 2011 to 2018, evidencing a pro-rich inequity trend. Age, residence, education, region, and economic status were the major identified contributors influencing the equity of health examination service utilization. CONCLUSIONS: A pro-rich inequity existed in health examination service utilization among the middle-aged and elderly population in China. Reducing the wealth and regional gap, providing equal educational opportunities, and strengthening the capacity for chronic disease prevention and control are crucial for reducing the inequity in health examination service utilization.

Comprehensive landscape-style investigation of the molecular mechanism of acupuncture at ST36 single acupoint on different systemic diseases.

The principle of acupoint stimulation efficacy is based on traditional meridian theory. However, the molecular mechanisms underlying the therapeutic effects of acupoints in treating diseases remain unclear in modern scientific understanding. In this study, we selected the ST36 acupoint for investigation and summarized all relevant literature from the PubMed database over the past 10 years. The results indicate that stimulation of ST36 single acupoints has therapeutic effects mainly in models of respiratory, neurological, digestive, endocrine and immune system diseases. And it can affect the inflammatory state, oxidative stress, respiratory mucus secretion, intestinal flora, immune cell function, neurotransmitter transmission, hormone secretion, the network of Interstitial Cells of Cajal (ICC) and glucose metabolism of the organism in these pathological states. Among them, acupuncture at the ST36 single point has the most prominent function in regulating the inflammatory state, which can mainly affect the activation of MAPK signaling pathway and drive the "molecular-cellular" mode involving macrophages, T-lymphocytes, mast cells (MCs) and neuroglial cells as the core to trigger the molecular level changes of the acupuncture point locally or in the target organ tissues, thereby establishing a multi-system, multi-target, multi-level molecular regulating mechanism. This article provides a comprehensive summary and discussion of the molecular mechanisms and effects of acupuncture at the ST36 acupoint, laying the groundwork for future in-depth research on acupuncture point theory.

Effect of portulaca (Portulaca oleracea L.) extract on the quality and physicochemical attributes of vacuum-packed seasoned steaks during chilled storage.

BACKGROUND: Vacuum packaging has the ability to reduce oxidative deterioration and microbial-induced spoilage of meat. However, in an oxygen-free environment, it can lead to the development of an unappealing purplish-red color and a decrease in the water-holding capacity of meat, thereby impacting the overall meat quality. Portulaca oleracea L. (POL) is a homology of medicine and food known for its exceptional antioxidant and antimicrobial properties. RESULTS: The aim of our present study was to investigate the antioxidant and antimicrobial ability of n-butanol phase extract of POL and the effect of POL extract incorporation on the quality (water-holding capacity, shear force, color, and texture) and physicochemical (pH, total volatile base nitrogen, and total viable counts) attributes of vacuum-packed seasoned steaks at 4 °C over a 15-day period. Results showed that the POL extract had excellent antioxidant and antimicrobial capacity. Furthermore, the addition of POL extract significantly inhibited protein oxidation and microbial growth of steaks (P < 0.05), and improved the water-holding capacity, color properties, and tenderness (P < 0.05). Moreover, there were no significant differences (P > 0.05) in the color, water-holding capacity, or tenderness between the 0.5 and 1 g kg-1 POL extract treatment groups compared to the sodium nitrite control group. CONCLUSION: These results indicate that POL extract had the potential to replace sodium nitrite due to its ability to hinder protein oxidation and microbial growth of vacuum-packed seasoned steaks, while enhancing the color, water-holding capacity, and tenderness of seasoned steaks. © 2024 Society of Chemical Industry.

Clinical value of oral contrast-enhanced ultrasonography in diagnosis of gastric tumors.

BACKGROUND: The incidence of gastric cancer remains high, and it is the sixth most common cancer and the fourth leading cause of cancer deaths worldwide. Oral contrast-enhanced ultrasonography is a simple, non-invasive, and painless method for the diagnosis of gastric tumors. AIM: To explore the diagnostic value of oral contrast-enhanced ultrasonography for the detection of gastric tumors. METHODS: The screening results based on oral contrast-enhanced ultrasonography and electronic gastroscopy were compared with those of the postoperative pathological examination. RESULTS: Among 42 patients with gastric tumors enrolled in the study, the diagnostic accordance rate was 95.2% for oral contrast-enhanced ultrasonography (n = 40) and 90.5% for electronic gastroscopy (n = 38) compared with postoperative pathological examination. The Kappa value of consistency test with pathological findings was 0.812 for oral contrast-enhanced ultrasonography and 0.718 for electronic gastroscopy, and there was no significant difference between them (P = 0.397). For the TNM staging of gastric tumors, the accuracy rate of oral contrast-enhanced ultrasonography was 81.9% for the overall T staging and 50%, 77.8%, 100%, and 100% for T1, T2, T3, and T4 staging, respectively. The sensitivity and specificity were both 100% for stages T3 and T4. The diagnostic accuracy rate of oral contrast-enhanced ultrasonography was 93.8%, 80%, 100%, and 100% for stages N0, N1-N3, M0, and M1, respectively. CONCLUSION: The accordance rate of qualitative diagnosis by oral contrast-enhanced ultrasonography is comparable to that of gastroscopy, and it could be used as the preferred method for the early screening of gastric tumors.

Barriers and facilitators of implementing electronic monitors to improve adherence and health outcomes in tuberculosis patients: protocol for a systematic review based on the Consolidated Framework for Implementation Research.

BACKGROUND: Tuberculosis (TB) has been regarded as 'a relentless scourge', increasing morbidity and mortality and burdening vulnerable populations. Poor adherence to TB treatment and ineffective traditional interventions hinders TB control. A novel TB approach called 'electronic monitors', equipping medication boxes with daily audio or visual reminders for electronically monitoring medication intake, seems promising in improving adherence and health outcomes and overcoming the weaknesses of traditional interventions. However, no review has systematically examined and synthesized the influencing factors of implementing electronic monitors. Implementation research offers the means to analyse the influencing factors of the implementation and its process, fitting well with the aim of this review. Therefore, the widely recognized Consolidated Framework for Implementation Research (CFIR), which offers a common taxonomy for evaluating intervention implementation, will be adopted to systematically identify barriers and facilitators of the electronic monitors for improving adherence and health outcomes in patients with TB. METHODS AND ANALYSIS: The systematic review will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Literature research will be conducted in five electronic databases (Ovid MEDLINE, CINAHL, EMBASE, Cochrane Library and Web of Science) to identify the barriers and facilitators of implementing electronic monitors in patients with TB. The CFIR will be used as a guide for categorizing and synthesizing the barriers and facilitators. Study screening, data extraction, quality appraisal and data analysis will be conducted by two independent reviewers. The use of additional reviewers will solve any disagreements between the two reviewers. DISCUSSION: Given the increased prominence of TB epidemiology and the adherence problem of electronic monitors, there is a solid rationale for synthesizing the existing studies via the CFIR. The findings and conclusion of this review will lay bare the achievements and effectiveness of implementing electronic monitors, as well as the attendant gaps and limitations. Further strategies for facilitating the implementation of electronic monitors will also be explored. This review will be of essential significance for research and practice, supporting future academic research initiatives centred on patients with TB and aiding electronic monitor design in lowering the morbidity and mortality associated with TB disease. TRIAL REGISTRATION NUMBER: PROSPERO: CRD42023395747.

Association between resolved hepatitis B virus infection and femoral and spinal bone mineral density in American adults: a cross-sectional study.

Background: Hepatitis B virus (HBV) infection is a global health concern that can potentially affect bone health. However, the specific association between resolved HBV infection and bone mineral density (BMD) remains unclear. This cross-sectional study aimed to investigate the potential association between resolved HBV infection and femoral and spinal BMD in adults in the United States. Methods: This cross-sectional study included participants aged 20-79 years with negative HBV surface antigen (HBsAg) from the 2005-2010, 2013-2014, and 2017-2018 cycles of the National Health and Nutrition Examination Survey. Resolved HBV infection was defined as negative HBsAg with positive HBV core antibody. BMD was measured using dual-energy X-ray absorptiometry. Propensity score matching (PSM) was performed to balance baseline characteristics. Results: A total of 10,333 eligible participants were identified and matched, of whom 737 (7.1%) had resolved HBV infection. Men with resolved HBV infection had significantly lower femoral and spinal BMD compared to those with no HBV infection, both before and after PSM. In the matched population, resolved HBV infection in men was negatively associated with femoral BMD (ß= -0.024, 95% CI: -0.047 to -0.002, p = 0.0332) and spinal BMD (ß= -0.025, 95% CI: -0.048 to -0.002, p = 0.0339). Postmenopausal women exhibited similar trends to men, while premenopausal women showed a tendency towards higher BMD, although statistical significance was not consistently achieved. Subgroup and sensitivity analyses supported the robustness of the findings. Conclusion: The study suggests a negative association between resolved HBV infection and femoral and spinal BMD in adult men in the United States. It highlights the importance of routine bone density assessments and the consideration of anti-osteoporotic therapy, if necessary, in individuals with resolved HBV infection.

Tea polyphenols coated sodium alginate-gelatin 3D edible scaffold for cultured meat.

This study aimed to use edible scaffolds as a platform for animal stem cell expansion, thus constructing block-shaped cell culture meat. The tea polyphenols (TP)-coated 3D scaffolds were constructed of sodium alginate (SA) and gelatin (Gel) with good biocompatibility and mechanical support. Initially, the physicochemical properties and mechanical properties of SA-Gel-TP scaffolds were measured, and the biocompatibility of the scaffolds was evaluated by C2C12 cells. SEM results showed that the scaffold had a porous laminar structure with TP particles attached to the surface, while FT-IR results also demonstrated the encapsulation of TP coating on the scaffold. In addition, the porosity of all scaffolds was higher than 40% and the degradation rate during the incubation cycle was less than 40% and the S2-G1-TP0.1-3 h scaffold has excellent cell adhesion and extension. Subsequently, we inoculated rabbit skeletal muscle myoblasts (RbSkMC) on the scaffold and induced differentiation. The results showed good adhesion and extension behavior of RbSkMC on S2-G1-TP0.1-3 h scaffolds with high expression of myogenic differentiation proteins and genes, and SEM results confirmed the formation of myotubes. Additionally, the adhesion rate of cells on scaffolds with TP coating was 1.5 times higher than that on scaffolds without coating, which significantly improved the cell proliferation rate and the morphology of cells with extension on the scaffolds. Furthermore, rabbit-derived cultured meat had similar appearance and textural characteristics to fresh meat. These conclusions indicate the high potential of the scaffolds with TP coating as a platform for the production of cultured meat products.

Research progress on the molecular mechanism of electroacupuncture at "Zusanli" (ST36) for regulating gastrointestinal dysfunction. / 电针"足三里"è°ƒèŠ‚èƒƒè‚ åŠŸèƒ½å¼‚å¸¸çš„åˆ†å­æœºåˆ¶ç ”ç©¶è¿›å±•.

Gastrointestinal dysfunction is manifested as digestive symptoms. Clinically, Zusanli (ST36) is crucial in the acupoint prescriptions of acupuncture no matter which type of the disease is differentiated in traditional Chinese medicine, but the underlying mechanism remains to be explored. Aiming to summarize the current status of the researches in terms of ameliorating gastrointestinal mucosal damage and regulating gastrointestinal motility disorders, we systematically reviewed the basic researches on the intervention with electroacupuncture (EA) at "ST36" in treatment of the diseases related to gastrointestinal dysfunction in the past 5 years, after searching the articles from Chinese and English databases. The results suggest that EA at ST36 may regulate the local gastrointestinal inflammation, oxidative stress and immune microenvironment to relieve gastrointestinal mucosal damage and adjust gastrointestinal motility disorders by means of modulating the central and peripheral nerve signaling as well as the function of mast cells and Cajal interstitial cells.

Kinesin-14 KIFC1 promotes acrosome formation and chromatin maturation during mouse spermiogenesis.

KIFC1, a member of kinesin-14 subfamily motors, is essential for meiotic cell division and acrosome formation during spermatogenesis. However, the functions of KIFC1 in the formation and maintenance of the acrosome in male germ cells remain to be elucidated. In this study, we report the structural deformities of acrosomes in the in vivo KIFC1 inhibition mouse models. The proacrosomal vesicles diffuse into the cytoplasm and form atypical acrosomal granules. This phenotype is consistent with globozoospermia patients and probably results from the failure of the Golgi-derived vesicle trafficking and actin filament organization. Moreover, the multinucleated and undifferentiated spermatogenic cells in the epidydimal lumen after KIFC1 inhibition reveal the specific roles of KIFC1 in regulating post-meiotic maturation. Overall, our results uncover KIFC1 as an essential regulator in the trafficking, fusion and maturation of acrosomal vesicles during spermiogenesis.

Global trends in perioperative stroke research from 2003 to 2022: a web of science-based bibliometric and visual analysis.

Background: Perioperative stroke is a potentially devastating complication in surgical patients, which has attracted global attention. This retrospective bibliometric and visual analysis evaluates the status and global trends in perioperative stroke research. Methods: Papers published between 2003 and 2022 were retrieved from the Web of Science core collection. Extracted data were summarized and analyzed using Microsoft Excel and further bibliometric and co-occurrence analyses were conducted using VOSviewer and CiteSpace software. Results: Publications on perioperative stroke have increased over the years. The USA topped the list of countries with the highest number of publications and citations, while Canada had the highest mean citation frequency. The Journal of Vascular Surgery and Annals of Thoracic Surgery had the highest number of publications and citation frequency for perioperative stroke. Regarding authors, Malas, Mahmoud B. contributed the most publications to the field, and Harvard University had the highest number of publications (409 papers). Based on an overlay visualization map, timeline view, and the strongest strength burst of keywords, "antiplatelet therapy," "antithrombotic therapy," "carotid revascularization," "bleeding complications," "postoperative cognitive dysfunction," "intraoperative hypotension," "thrombectomy," "cerebral revascularization," "valve surgery," "tranexamic acid," and "frozen elephant trunk" were trending topics in perioperative stroke research. Conclusion: Publications regarding perioperative stroke have experienced rapid growth in the past 20 years and are likely to continuously increase. Research on perioperative antiplatelet and antithrombotic, cardiovascular surgery, postoperative cognitive dysfunction, thrombectomy, tranexamic acid, and frozen elephant trunk has attracted increasing attention, and these topics are emerging hotspots of present research and possible candidates for future research.

Catastrophic health expenditure of households with hypertension: a comparative study in China.

Objectives: The aim of this study was to understand the impact of multimorbidity on catastrophic health expenditures for people with hypertension. Methods: Data were obtained from the China Health and Retirement Longitudinal Study (CHARLS) in 2018, 8,342 adults were included in our analysis. Propensity score matching method was used to compare the risk of catastrophic health expenditures between the hypertension patients (treatment group) and those without any chronic disease (control group) in middle-aged and older adults. Patients with hypertension were also divided into two groups: only hypertension and multimorbidity. Results: Hypertension increased the likelihood of CHE by 11.3% in older adults. Further analysis showed that hypertension alone does not increase the risk of CHE, and the risk of CHE in hypertension patients with multimorbidity was 12.9% higher than those without chronic disease. Conclusion: Our study highlights the importance of healthy management of patients with only hypertension and preventing them from developing multimorbidity.

Chemosensory protein regulates the behavioural response of Frankliniella intonsa and Frankliniella occidentalis to tomato zonate spot virus-Infected pepper (Capsicum annuum).

Many herbivorous insects rely on plant volatiles to locate their host plants. Vector-borne viral infections induce changes in plant volatiles, which render infected plants more attractive to insect vectors. However, the detailed mechanisms underlying the olfactory responses of insect vectors induced by the volatiles produced by virus-infected plants are poorly understood. Here, we show that volatiles emitted by pepper (Capsicum annuum) plants infected with tomato zonate spot virus (TZSV), particularly the volatile cis-3-hexenal, which is recognized by chemosensory protein 1 of the thrips Frankliniella intonsa (FintCSP1), are more attractive to F. intonsa than the volatiles emitted by non-infected pepper plants. FintCSP1 is highly abundant in the antenna of F. intonsa. Silencing of FintCSP1 significantly decreased electroantennogram responses of F. intonsa antennae to cis-3-hexenal and impaired thrips' responses to TZSV-infected pepper plants and cis-3-hexenal, as assessed using a Y-tube olfactometer. Three-dimensional model predictions indicated that FintCSP1 consists of seven α-helixes and two disulfide bridges. Molecular docking analysis suggested that cis-3-hexenal is positioned deep inside the binding pocket of FintCSP1 and binds to residues of the protein. We combined site-directed mutagenesis and fluorescence binding assays and identified three hydrophilic residues, Lys26, Thr28, and Glu67, of FintCSP1 as being critical for cis-3-hexenal binding. Furthermore, CSP of F. occidentalis (FoccCSP) is also a key olfactory protein involved in modulating the behaviour of F. occidentalis to TZSV-infected pepper. This study revealed the specific binding characteristics of CSPs to cis-3-hexenal and confirmed the general hypothesis that virus infections induce changes in host volatiles, which can be recognized by the olfactory proteins of the insect vector to enhance vector attraction and this may facilitate viral spread and transmission.

Gellan gum-gelatin scaffolds with Ca2+ crosslinking for constructing a structured cell cultured meat model.

As an emerging technology to obtain protein by culturing animal-derived cells in vitro, it is crucial to construct 3D edible scaffolds to prepare structured cell cultured meat products. In this study, a scaffold based on gellan gum (GG)-gelatin (Gel) was prepared and further cross-linked with Ca2+. FTIR confirmed the electrostatic interaction between GG and Gel and the ionic cross-linking of Ca2+ and carboxyl groups, and SEM images showed the porous structure of the scaffolds. The staining results showed that scaffolds with high concentrations of Ca2+ had higher biocompatibility than scaffolds with low concentrations of Ca2+ and non-crosslinked scaffolds, and scaffolds Ca2+-GG2-Gel3-0.5 adhered to more cells and were more conducive to cell spreading. The immunofluorescence staining, SEM images, Western blot, and RT-qPCR showed that the scaffolds supported the proliferation and myogenic differentiation of chicken skeletal muscle satellite cells (CSMSCs) and myotubes were formed on the scaffolds. Finally, the scaffolds were stained and fried after culturing. The results of the textural and chromatic analysis showed that the texture and color of the scaffolds were similar to fresh meat and meat products. These results showed that ionically crosslinked GG-Gel scaffolds are biocompatible and stable for structured cell cultured meat models.

Suppression mechanism of L-lysine on the Epigallocatechin-3-gallate-induced loss of myofibrillar protein gelling potential.

As a natural antioxidant, Epigallocatechin-3-gallate (EGCG) needed to be added in high doses to maintain the quality of meat products. However, high doses of EGCG caused the excessive aggregation of myofibrillar protein (MP), which damaged the gel properties of MP gels. Therefore, the purpose of this study was to investigate the mitigation of EGCG-induced loss of MP gelling potential by L-Lysine (L-Lys). The results showed that the addition of 20 mM L-Lys induced excessive unfolding and loose aggregation of MP at 10 µmol/g EGCG, and hence, reducing the solubility (14.5%) and the tryptophan fluorescence, and forming a network structure with a large aperture. Therefore, the cooking loss was decreased from 29.20% to 15.13%, and the strength of MP gels was decreased from 0.35 N to 0.17 N. However, L-Lys hindered the hydrogen bonding interactions and hydrophobic interactions between MP and EGCG by competing the binding sites of MP at 50 µmol/g EGCG, which was supported by the Zeta potential, surface hydrophobicity, FTIR and molecular docking analysis. Thus L-Lys mitigated the protein aggregation caused by 50 µmol/g EGCG, improved the solubility (23.02%∼86.99%) and apparent viscosity, which were beneficial for the formation of a continuous network structure in MP gels. Therefore, the cooking loss of MP gels was decreased from 52.40% to 41.30%, and the gel strength was enhanced from 0.13 N to o.22 N with 20 mM L-Lys addition. The present study could provide a new strategy for increasing the amounts of EGCG in meat products without damaging the gel properties of meat products.