Antagonistic Activity of Volatile Organic Compounds Produced by Acid-Tolerant Pseudomonas protegens CLP-6 as Biological Fumigants To Control Tobacco Bacterial Wilt Caused by Ralstonia solanacearum.

Tobacco bacterial wilt, which is caused by Ralstonia solanacearum, is a devastating soilborne disease of tobacco worldwide and is widespread in the continuously acidic fields of southern China. Here, the fumigation activity under different pH conditions, component identification, and bioactivity of the volatile organic compounds (VOCs) produced by an acid-tolerant strain, Pseudomonas protegens CLP-6, were investigated. There was a wide antimicrobial spectrum of the VOCs against phytopathogens, including four bacteria, eight fungi, and two oomycetes. The antagonistic activity of the VOCs against R. solanacearum was proportionally correlated with the concentration of the inoculum, amount, culture time, and culture pH for CLP-6. The number of gene copies of R. solanacearum was significantly inhibited by VOCs produced at pH 5.5 in vivo. The control effect of VOCs emitted at pH 5.5 was 78.91% for tobacco bacterial wilt, which was >3-fold greater than that at pH 7.0. Finally, the main volatile compounds were identified by solid-phase microextraction (SPME)-gas chromatography-mass spectroscopy (GC-MS) as S-methyl thioacetate, methyl thiocyanate, methyl disulfide, 1-decene, 2-ethylhexanol, 1,4-undecadiene, 1-undecene, 1,3-benzothiazole, and 2,5-dimethylpyrazine, and the inhibition rates of 1,3-benzothiazole, 2-ethylhexanolmethyl thiocyanate, dimethyl disulfide, and S-methyl thioacetate were 100%, 100%, 88.91%, 67.64%, and 53.29%, respectively. S-Methyl thioacetate was detected only at pH 5.5. In summary, VOCs produced by P. protegens CLP-6 had strong antagonistic activities against phytopathogens, especially R. solanacearum, under acidic conditions and could be used to develop a safe and additive fumigant against R. solanacearum on tobacco and even other Solanaceae crop bacterial wilt diseases in acidic fields. IMPORTANCE VOCs produced by beneficial bacteria penetrate the rhizosphere to inhibit the growth of plant-pathogenic microorganisms; thus, they have the potential to be used as biological agents in controlling plant diseases. Tobacco bacterial wilt, which is caused by the acidophilic pathogen R. solanacearum, is a major bacterial disease in southern China and is prevalent in acidic soil. In this study, we discovered that the VOCs produced by P. protegens CLP-6 had excellent inhibitory effects on important plant pathogens. Moreover, two of the VOCs, namely, 1,3-benzothiazole and 2-ethylhexanol, had excellent inhibitory effect on R. solanacearum, and another VOC substance, methyl thiocyanate, was produced only at pH 5.5. The VOCs produced by the acid-tolerant strain P. protegens CLP-6 may have potential as environment-friendly microbial fumigant agents for bacterial wilt of tobacco or even other Solanaceae crops in acidic soils in China.

Changes in volatile profile and related gene expression during senescence of tobacco leaves.

BACKGROUND: Volatile organic compounds are critical for food flavor and play important roles in plant-plant interactions and plants' communications with the environment. Tobacco is well-studied for secondary metabolism and most of the typical flavor substances in tobacco leaves are generated at the mature stage of leaf development. However, the changes in volatiles during leaf senescence are rarely studied. RESULTS: The volatile composition of tobacco leaves at different stages of senescence was characterized for the first time. Comparative volatile profiling of tobacco leaves at different stages was performed using solid-phase microextraction coupled with gas chromatography/mass spectrometry. In total, 45 volatile compounds were identified and quantified, including terpenoids, green leaf volatiles (GLVs), phenylpropanoids, Maillard reaction products, esters, and alkanes. Most of the volatile compounds showed differential accumulation during leaf senescence. Some terpenoids, including neophytadiene, ß-springene, and 6-methyl-5-hepten-2-one, increased significantly with the progress of leaf senescence. Hexanal and phenylacetaldehyde also showed increased accumulation in leaves during senescence. The results from gene expression profiling indicated that genes involved in metabolism of terpenoids, phenylpropanoids, and GLVs were differentially expressed during leaf yellowing. CONCLUSION: Dynamic changes in volatile compounds during tobacco leaf senescence are observed and the integration of gene-metabolites datasets offers important readouts for the genetic control of volatile production during the process of leaf senescence. © 2023 Society of Chemical Industry.

Characterization of trichome-specific BAHD acyltransferases involved in acylsugar biosynthesis in Nicotiana tabacum.

Glandular trichomes of tobacco (Nicotiana tabacum) produce blends of acylsucroses that contribute to defence against pathogens and herbivorous insects, but the mechanism of assembly of these acylsugars has not yet been determined. In this study, we isolated and characterized two trichome-specific acylsugar acyltransferases that are localized in the endoplasmic reticulum, NtASAT1 and NtASAT2. They sequentially catalyse two additive steps of acyl donors to sucrose to produce di-acylsucrose. Knocking out of NtASAT1 or NtASAT2 resulted in deficiency of acylsucrose; however, there was no effect on acylsugar accumulation in plants overexpressing NtASAT1 or NtASAT2. Genomic analysis and profiling revealed that NtASATs originated from the T subgenome, which is derived from the acylsugar-producing diploid ancestor N. tomentosiformis. Our identification of NtASAT1 and NtASAT2 as enzymes involved in acylsugar assembly in tobacco potentially provides a new approach and target genes for improving crop resistance against pathogens and insects.

Effects of a vegetarian diet combined with exercise on lipid profiles and blood pressure: A systematic review and meta-analysis.

We aimed to evaluate the combined effects of a vegetarian diet (VD) and exercise on total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), systolic blood pressure (SBP), and diastolic blood pressure (DBP) parameters. A literature search was conducted in electronic databases from build to February 27, 2022. Data were synthesized using random effects model and were ＿expressed as standardized mean difference (SMD)/weighted mean difference (WMD) and 95% confidence interval (CI). Overall, 27 trials with 9,251 participants were included. Pooled results indicated that the combination of a VD and exercise significantly reduced TC (SMD: -0.524; 95% CI: -0.602, -0.446; p < 0.001), LDL-C (SMD: -0.379; 95% CI: -0.471, -0.287; p < 0.001), HDL-C (SMD: -0.213; 95% CI: -0.299, -0.126; p < 0.001), TG (SMD: -0.090; 95% CI: -0.160, -0.020; p = 0.012), SBP (WMD: -7.664 mm Hg; 95% CI: -9.219, -6.109 mm Hg; p < 0.001), and DBP (WMD: -4.347 mm Hg; 95% CI: -5.099, -3.596 mm Hg; p < 0.001). These parameters were reduced more following a low-fat VD, or a mixed high-frequency exercise, especially under strict supervision. Surprisingly, the decreased HDL-C due to VD was observed to recover with the prolongation of exercise.

Virtual reality-based targeted cognitive training program for Chinese older adults: A feasibility study.

OBJECTIVE: To investigate the acceptance and tolerance of a targeted cognitive training program with virtual reality (VR) in Chinese older adults. METHODS: We developed a VR-based program consisting of five games for cognitive training. Fourteen older adults voluntarily participated in the VR training program from January 1 to 22, 2022. The tolerance of the participants and acceptance of the video-based training were assessed after training. RESULTS: Of the participants, 8 (57.1%) had normal cognitive function, and 6 (42.9%) had cognitive impairment. The participants tolerated the program well with a total SSQ (simulated sickness questionnaire) score of 10.42±12.97. Regarding acceptance, 97.6% of subjects found VR equipment to be easy to use, 76.2% said it was a positive experience, and 57.1% thought VR devices were attractive. CONCLUSION: This study shows that VR-based cognitive training was well tolerated by Chinese older adults, without major or severe adverse events.

Open Abdomen Improves Survival in Patients With Peritonitis Secondary to Acute Superior Mesenteric Artery Occlusion.

BACKGROUND: Damage control surgery and open abdomen (OA) have been extensively used in the severe traumatic patients. However, there was little information when extended to a nontrauma setting. The purpose of this study was to evaluate whether the liberal use of OA as a damage control surgery adjunct improved the clinical outcome in acute superior mesenteric artery occlusion patients. STUDY DESIGN: A single-center, retrospective cohort review was performed in a national tertiary surgical referral center. RESULTS: Forty-four patients received OA (OA group) and 65 patients had a primary fascial closure (non-OA group) after diagnosed as peritonitis secondary to acute superior mesenteric artery occlusion from January, 2005 to June, 2016. Revascularization was achieved through endovascular aspiration embolectomy, open embolectomy, or percutaneous stent. No difference of bowel resection length was found between groups in the first emergency surgery. However, more non-OA patients (35.4%) required a second-look enterectomy to remove the residual bowel ischemia than OA patients (13.6%, P<0.05). OA was closed within a median of 7 days (4 to 15 d). There was a mean of 134 cm residual alive bowel in OA, whereas 96 cm in non-OA. More non-OA patients suffered from intra-abdominal sepsis (23.1% vs. 6.8%, P<0.01), intra-abdominal hypertension (31% vs. 0, P<0.01), and acute renal failure (53.8% vs. 31.8%, P<0.05) than OA group after surgery. Short-bowel syndrome occurred infrequently in OA than non-OA patients (9.1% vs. 36.9%, P<0.01). OA significantly decreased the 30-day (27.3% vs. 52.3%, P<0.01) and 1-year mortality rate (31.8 % vs. 61.5%, P<0.01) compared with non-OA group. CONCLUSIONS: Liberal use of OA, as a damage control adjunct avoided the development of intra-abdominal hypertension, reduced sepsis-related complication, and improved the clinical outcomes in peritonitis secondary to acute SMA occlusion.

[Analyses of exercise-induced muscle damage-specific microRNA expression and molecular target of sarcolemmal damage in rats].

In the present study, we were to screen the specific microRNA (miRNA) of exercise-induced muscle damage (EIMD) and assess the EIMD-specific miRNAs-regulated target of sarcolemmal damage in rats. Twenty-four male Sprague-Dawley (SD) rats were randomly divided into 3 groups, which included sedentary (C), 24 h post-exercise (E24) and 48 h post-exercise (E48) groups. Rat EIMD model was established by an acute eccentric exercise, i.e., a downhill running treatment at -16º gradient. EIMD characteristics were verified by Evans blue dye staining, differentially expressed miRNAs were detected by microarray assay, EIMD-specific miRNAs expressions were further validated by real-time quantitative RT-PCR (RT-qPCR), and targets of the miRNAs were predicted based on mRNA expressions of associated proteins and related pathway core molecules of sarcolemmal damage. Two EIMD-specific expressed miRNAs, including miR-206-3p and miR-139-3p, were found in the study. There was a significantly negative correlation (P < 0.05) between miR-206-3p expression and dystrophin (r = -0.68), utrophin (r = -0.64), JNK (r = -0.62) or ERK1 (r = -0.68) respectively, but no correlation was found between miR-139-3p and these biomolecules. The results suggest that: i) the expression profile of miRNAs in rat is significantly affected by EIMD, ii) miR-206-3p and miR-139-3p are the EIMD-specific miRNAs, and iii) miR-206-3p may control sarcolemmal damage by regulating dystrophin, utrophin, JNK and ERK1.

A Modified Model for Assessment for Retreatment with Transarterial Chemoembolization in Chinese Hepatocellular Carcinoma Patients.

PURPOSE: To develop a modified assessment for retreatment with transarterial chemoembolization (mART) score that may be more suitable for Chinese patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Chinese patients with HCC who were treated with transarterial chemoembolization in four hospitals were included. A univariate analysis and a multivariate forward Cox regression analysis were used to identify significant prognostic factors of overall survival (OS). A point scoring model was subsequently developed from the training cohort, and the validation process was performed in the validation cohort. RESULTS: The study included 259 patients (124 patients in the training cohort and 135 patients in the validation cohort). Increase in Child-Pugh scores relative to the baseline (P < .001), Barcelona Clinic Liver Cancer (BCLC) stage B before first transarterial chemoembolization (P = .001), and absence of radiologic tumor response (P < .001) were identified as negative prognostic factors for OS and were used to create the mART scores. BCLC staging was substituted for aspartate aminotransferase increase in the mART scores. The mART scores differentiated two groups with distinct prognosis by a cutoff score of 2.5 points (22.9 mo [95% confidence interval (CI), 17.4-28.4] vs 8.9 mo [95% CI, 7.5-10.3] in median survival; P < .001). In the validation cohort, the C index in assessment for retreatment with transarterial chemoembolization (ART) criteria was 0.64, whereas it was 0.82 in mART criteria. CONCLUSIONS: In Chinese patients with HCC, mART score of > 2.5 before second transarterial chemoembolization was associated with poor prognosis. The mART score was probably better validated compared with the ART score.

Good Clinical Outcomes in Budd-Chiari Syndrome with Hepatic Vein Occlusion.

BACKGROUND: Budd-Chiari syndrome (BCS) with hepatic vein (HV) occlusion is manifested by severe liver damage in acute cases and esophageal variceal bleeding or refractory ascites in chronic cases, which is difficult to differentiate from cirrhotic portal hypertension. AIMS: To evaluate the clinical efficacy and safety of HV angioplasty and transjugular intrahepatic portosystemic shunt (TIPS) in the treatment of BCS with HV occlusion. METHODS: Between May 1995 and December 2014, 60 patients with HV occlusive BCS underwent HV angioplasty or TIPS. BCS was subacute or chronic in 55 patients and acute in 5 patients. HV angioplasty was performed in 18 patients with HV occlusion, combined HV and IVC angioplasty in 9 patients with HV and IVC occlusion, TIPS in 12 patients with HV occlusion, and modified TIPS in 21 patients with extensive HV occlusion. RESULTS: The interventional procedure was successfully performed in all 60 patients. The portal pressure decreased from 41.23 ± 10.46 cmH2O preoperatively to 26.68 ± 6.46 cmH2O postoperatively, while the portal flow velocity increased from 14.31 ± 10.43 to 52.16 ± 13.68 cm/s in patients undergoing TIPS or modified TIPS. During hospitalization, two patients died from hepatic failure, and acute shunt occlusion occurred in two other patients during subsequent treatment with repeated intervention. During 82.25 ± 46.16 months of follow-up, three patients underwent re-intervention with a stenotic shunt, and other three with repeated dilation of the stenotic HV. CONCLUSION: HV angioplasty and TIPS yield excellent long-term outcomes in patients with HV occlusive BCS.

Multiresidue determination of 114 multiclass pesticides in flue-cured tobacco by solid-phase extraction coupled with gas chromatography and tandem mass spectrometry.

A sensitive and robust multiresidue method for the simultaneous analysis of 114 pesticides in tobacco was developed based on solid-phase extraction coupled with gas chromatography and tandem mass spectrometry. In this strategy, tobacco samples were extracted with acetonitrile and cleaned up with a multilayer solid-phase extraction cartridge Cleanert TPT using acetonitrile/toluene (3:1) as the elution solvent. Two internal standards of different polarity were used to meet simultaneous pesticides quantification demands in the tobacco matrix. Satisfactory linearity in the range of 10-500 ng/mL was obtained for all 114 pesticides with linear regression coefficients higher than 0.994. The limit of detection and limit of quantification values were 0.02-5.27 and 0.06-17.6 ng/g, respectively. For most of the pesticides, acceptable recoveries in the range of 70-120% and repeatabilities (relative standard deviation) of <11% were achieved at spiking levels of 20, 100, and 400 ng/g. Compared with the reported multiresidue analytical method, the proposed method provided a cleaner test solution with smaller amounts of pigments, fatty acids as well as other undesirable interferences. The development and validation of the high sensitivity, high selectivity, easy automation, and high-throughput analytical method meant that it could be successfully used for the determination of pesticides in tobacco samples.

Associations of cardiorespiratory fitness with cardiovascular disease risk factors in middle-aged Chinese women: a cross-sectional study.

BACKGROUND: High levels of physical activity (PA) and cardiorespiratory fitness (CRF) are each associated with a favorable cardiovascular disease (CVD) risk profile. However, the relationship between CRF and obesity is still inconsistent across studies, and there has been no thorough exploration of the independent contribution of CRF to different CVD risk factors in Chinese women. This study investigated the relationship between CRF and CVD risk factors in 40-49 year old women in Beijing. METHODS: The study included 231 urban-dwelling asymptomatic 40-49 year old women. Body mass index (BMI), body fat percentage (BF%), blood glucose, blood lipids, blood pressure, and pulse wave velocity (PWV) were measured at rest. Cycle ergometer exercise tests were conducted to assess CRF as indicated by maximal oxygen uptake (VO(2max)). Participants were categorized into three CRF levels (low, moderate and high). RESULTS: High CRF level was associated with significantly less BF%, lower PWV, and higher weekly physical activity compared with low and moderate CRF (P < 0.05). Compared to high CRF, the odds ratios for having ≥3 main CVD risk factors (overweight, hypertension, and dyslipidemia) in low and moderate CRF were 2.09 (95% CI: 1.48-2.94) and 1.84 (95% CI: 1.29-2.62), respectively. The proportion of participants with clinical ST segment depression and prolonged QTC interval during cycle ergometer testing was significantly higher in women with low CRF. CONCLUSIONS: Overall, Chinese middle-aged women demonstrated a moderate level of CRF. CRF was independently associated with CVD risk factors, including overweight, hypertension, dyslipidemia, arterial stiffness, and abnormal ECG during exercise, with the least fit women exhibiting the highest number of CVD risk factors.

[Hepatic venousaplasty and transjugular intrahepatic portosystemic shunt in the treatment of Budd-Chiari syndrome with occlusion of the hepatic veins].

OBJECTIVE: To determine the outcome of hepatic venousaplasty and transjugular intrahepatic portosystemic shunt (TIPS) in the treatment of the Budd-Chiari syndrome with occlusion of the hepatic veins. METHODS: Fifty patients of the Budd-Chiari syndrome with occlusion of the hepatic veins (23 males and 27 females, with a mean age of (39 ± 11) years) were elected for venousaplasty or TIPS. The average of Child-Pugh scores was 9.6 ± 2.6. Three patients had a acute course of the disease, while 47 patients had a subacute or a chronic course of the disease. The clinical presentation was ascites in all 50 cases, with concomitant upper gastrointestinal bleeding in 10 patients, hepatorenal syndrome in 4 patients and impaired liver function in all patients. Hepatic venousplasty was performed for 12 patients with occlusion of hepatic venous. Hepatic and inferior caval venousplasty were performed for 6 patients with occlusion of hepatic and inferior caval vein. TIPS was performed for 13 patients with occlusion of small hepatic vein. Modified TIPS was performed for 19 patients with extensive occlusion of hepatic vein. RESULTS: The procedure of treatment was successfully performed in all patients. The shunt reduced the portosystemic pressure gradient from (41 ± 10) to (27 ± 6) cmH2O (1 cmH2O = 0.098 kPa, t = 20.20, P = 0.001) and improved the portal flow velocity from (14 ± 10) to (52 ± 14) cm/s (t = 15.02, P = 0.001) after TIPS or modified TIPS. Clinical symptoms and the biochemical test results improved significantly during 3 weeks after hepatic venousplasty and shunt treatment. During the hospitalization, the death occurred in 1 case due to hepatic failure and the acute occlusion of shunt was treated with secondary intervention in another case. The mean follow-up was (82 ± 46) months. The revisions of shunt with TIPS were needed in 2 patients and the inflation of stenosised hepatic vein in another 2 patients during the follow-up. All patients were still observed. CONCLUSION: Hepatic venousaplasty and TIPS provide an excellent outcome in patients of Budd-Chiari syndrome with occlusion of the hepatic veins.

Study on the correlation between the dominant microflora and the main flavor substances in the fermentation process of cigar tobacco leaves.

The flavor of cigar tobacco leaf determines the quality of finished cigar tobacco, and the enhancement of flavor generally relies on microbial fermentation. In this paper, the correlation between the dominant microorganisms and the main flavor substances of cigar tobacco leaves during fermentation and the correlation between the two were investigated to reveal the correlation between microorganisms and flavor and the metabolic pathways of microorganisms affecting the flavor substances. During the fermentation process, the main flavors of cigar tobacco leaves were sweet, light and grassy, with hexanal, 2,6-dimethylpyridine, nonanal, phenylacetaldehyde, naphthalene, and methyl benzoate as the main constituents, and the key microorganisms Haloferax mediterranei, Haloterrigena limicola, Candidatus Thorarchaeota archaeon SMTZ-45, the genera Methyloversatilis, Sphingomonas, Thauera, Pseudomonas, Penicillium, and Aspergillus. Correlation analysis revealed that fungi were negatively correlated with the main aroma and inhibited the main flavor substances, while bacteria were positively correlated with Benzoic acid, methyl ester in the main flavor substances, which was conducive to the accumulation of green aroma. Functional analysis revealed that the dominant bacterial population was producing aroma by metabolizing glycoside hydrolases and glycosyltransferases, performing amino acid metabolism, carbohydrate metabolism and film transport metabolism. The present study showed that the bacterial and fungal dominant microorganisms during the fermentation of cigar tobacco were influencing the production and degradation of the main flavor substances through the enzyme metabolism by the occurrence of the Merad reaction.

Comparison of efficacy of different route of administration of chemotherapy on unresectable, advanced gastric cancer.

BACKGROUND: The aim of this study was to compare the efficacy of two neoadjuvant chemotherapies (FLEEOX and XELOX) with different routes of administration for unresectable gastric cancer. METHODS: A total of 85 patients with unresectable gastric cancer hospitalized from January 2007 to December 2009 received neoadjuvant chemotherapy. The FLEEOX group (48 patients) received the FLEEOX regimen(fluorouracil, leucovorin, http://epirubicin, epotoside, and oxaliplatin), which combined arterial with venous administration for one or two cycles, while the XELOX group (37 patients) received XELOX (capecitabine plus oxaliplatin) via venous administration for two to four cycles. The clinical response and overall survival of the two groups were compared. RESULTS: In the FLEEOX group, the clinical response rate (RR) of chemotherapy was 85.4% (41 of 48 patients) and the median survival time was 25 months. The 1-year and 2-year disease-free survival (DFS) rates were 85.4% and 45.8%, respectively. In the XELOX group, the clinical RR was 59.5% and the median survival time was 9 months, while the 1-year and 2-year survival rates were 35.2% and 8.3%, respectively. The clinical RR, the R0 resection rate, the median survival time, and the 1-year and 2-year DFS rates were significantly better (P < 0.05) in the FLEEOX group than in the XELOX group. In addition, there were no significant differences in the rates of toxic and adverse reactions or post-operative complications between the two groups. CONCLUSIONS: For patients with a preoperative diagnosis of unresectable gastric cancer, the efficacy of the FLEEOX regimen, which combines arterial with venous administration, was better than that of the XELOX regimen, using venous administration only. This combination of arterial and venous administration could be useful for improving the efficacy of neoadjuvant chemotherapy for gastric cancer.

Exercise serum regulates uric acid transporters in normal rat kidney cells.

Hyperuricemia (HUA) refers to a physiological condition of high serum uric acid (SUA) level in the body, which may cause an increased risk of several chronic diseases. The kidney's impaired uric acid (UA) metabolism is an important reason for HUA. In this study, we tested the hypothesis that circulating factors produced during exercise regulate the expression of ABCC4, ABCG2, URAT1, and GLUT9 in normal rat kidneys and normal rat kidney cells (NRK-52E) and their relationship with NF-κB and NRF-2. NRK-52E cells were separately cultured by serum from 10 healthy SD rats who did not exercise (CON) and 10 healthy SD rats who did aerobic treadmill exercise for 6 weeks. Cells cultured by serum from rats who did aerobic treadmill exercise for 6 weeks were separated by without NRF-2 inhibitor (EXE) and with NRF-2 inhibitor (EXE + ML). SUA level of rats was tested by using dry chemical assays, xanthine oxidase (XOD) activity in serum and liver were tested by using enzyme colorimetry assays, protein expression in kidney and NRK-52E cells were tested by using Western-blot, and UA levels in the upper or lower chamber were tested by colorimetry assays. Aerobic exercise reduced SUA levels in rats but did not significantly affect on liver xanthine oxidase. It also increased the expression of some UA transporters in the kidney and NRK-52E cells and increased the cells' ability in UA excretion. When the NRF-2 was inhibited, the NF-κB and ABCG2 increased, and the expression of ABCC4, URAT1, and GLUT9 decreased. In conclusion, this study suggested that 6 weeks of aerobic treadmill exercise intervention may help to improve the excretion of UA in renal cells, suggesting that long-term aerobic exercise may be a means to prevent hyperuricemia.

[Protective effects of Lycium ruthenicum Murr. juice on alcoholic liver injury in rats].

Objective: To study the protective effects of Lycium ruthenicum Murr. juice on alcoholic liver injury in rats and explore the regulatory mechanism of toll-like receptors 4 (TLR4)/p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway in this process. Methods: Sixty male SD rats were randomly divided into control group (C), model group (M), low-dose Lycium ruthenicum Murr. juice group (LLM), medium-dose Lycium ruthenicum Murr. juice group (MLM) and high-dose Lycium ruthenicum Murr. juice group (HLM), 12 rats in each group. The group M, LLM, MLM and HLM were treated with 20 ml/kg (8 g/(kg·d)) ethanol (400 g/L) intragastrically and the gavage was divided into two sessions, group C was treated with an equal volume of distilled water at the same time point. Four hours before the first alcohol gavage session, rats in each dose group of Lycium ruthenicum Murr. juice were administered with 2.4, 4.8, 9.6 ml/(kg·d) Lycium ruthenicum Murr. juice respectively, and the other groups were given equal volume of distilled water at the corresponding time points. Four weeks later, the rats were sacrificed 24 hours after the end of the last experiment, blood and liver were collected. The liver index was calculated. The morphology of the liver was observed by HE staining. The expressions of hepatic TLR4, p38 MAPK and phosphorylated p38 mitogen-activated protein kinase (p-p38 MAPK) were detected by immunohistochemistry. The activities of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected by colorimetry. The levels of hepatic tumor necrosis factor-α (TNF-α), interleukin-1ß (IL-1ß), interleukin-10 (IL-10) and interleukin-18 (IL-18) were detected by enzyme linked immunosorbent assay. Results: Compared with group C, the alcoholic liver injury model was established successfully in Group M. Compared with group M, related indicators in each dose group of Lycium ruthenicum Murr. juice were improved, the improvement of hepatic morphology in group HLM was the most significant, the liver index, the levels of serum ALT, AST and hepatic TLR4, p38 MAPK/p-p38 MAPK ratio, TNF-α, IL-1ß, IL-18 were decreased (P＜ 0.05 or P＜0.01), while the level of hepatic IL-10 was increased (P＜0.01). Comparison among the dose groups of Lycium ruthenicum Murr. juice, the levels of liver index, serum AST and hepatic TLR4, p38 MAPK/p-p38 MAPK ratio, TNF-α, IL-18 in HLM were lower than those in LLM (P＜0.05 or P＜0.01); the level of hepatic IL-10 in HLM was higher than that in LLM and MLM (P＜0.05 or P＜0.01); the other indicators in each dose group had no statistical difference (P＞0.05). Conclusion: Lycium ruthenicum Murr. juice can improve the inflammatory stress by regulating TLR4/p38 MAPK signaling pathway, relieve alcoholic liver injury in rats, and the effect of high-dose group is better than the others.

Biocontrol potential of Bacillus velezensis EM-1 associated with suppressive rhizosphere soil microbes against tobacco bacterial wilt.

Tobacco bacterial wilt caused by Ralstonia solanacearum is one of the most devastating diseases. Microbial keystone taxa were proposed as promising targets in plant disease control. In this study, we obtained an antagonistic Bacillus isolate EM-1 from bacterial wilt-suppressive soil, and it was considered rhizosphere-resident bacteria based on high (100%) 16S rRNA gene similarity to sequences derived from high-throughput amplicon sequencing. According to 16S rRNA gene sequencing and MLSA, strain EM-1 was identified as Bacillus velezensis. This strain could inhibit the growth of R. solanacearum, reduce the colonization of R. solanacearum in tobacco roots, and decrease the incidence of bacterial wilt disease. In addition, strain EM-1 also showed a strong inhibitory effect on other phytopathogens, such as Alternaria alternata and Phytophthora nicotianae, indicating a wide antagonistic spectrum. The antimicrobial ability of EM-1 can be attributed to its volatile, lipopeptide and polyketide metabolites. Iturin A (C14, C15, and C16) was the main lipopeptide, and macrolactin A and macrolactin W were the main polyketides in the fermentation broth of EM-1, while heptanone and its derivatives were dominant among the volatile organic compounds. Among them, heptanones and macrolactins, but not iturins, might be the main potential antibacterial substances. Complete genome sequencing was performed, and the biosynthetic gene clusters responsible for iturin A and macrolactin were identified. Moreover, strain EM-1 can also induce plant resistance by increasing the activity of CAT and PPO in tobacco. These results indicated that EM-1 can serve as a biocontrol Bacillus strain for tobacco bacterial wilt control. This study provides a better insight into the strategy of exploring biocontrol agent based on rhizosphere microbiome.

Comparative Evaluation of Key Aroma-Active Compounds in Sweet Osmanthus (Osmanthus fragrans Lour.) with Different Enzymatic Treatments.

Sweet osmanthus (Osmanthus fragrans Lour.) (OF) is one of the ten most famous flowers in China for its unique and delicate fragrance. A combined solid-phase microextraction and solvent-assisted flavor evaporation method was used to accurately capture the overall aromatic profile and characterize the predominant odorants of fresh osmanthus with the help of gas chromatography (GC)-olfactometry and comprehensive two-dimensional GC-quadrupole time-of-flight mass spectrometry (GC × GC-QTOF-MS). Twenty-six volatiles were identified for the first time in OF. A total of 23 potent odorants, dominated by monoterpene oxides and C6 aliphatic aldehydes, were identified. The efficacy of pectinase, ß-glucosidase, and their combination on the aroma enhancement of OF was evaluated by quantitation of the target aroma components using GC-triple quadrupole-MS. The total concentration of key aroma components increased in all three enzyme treatment groups, and the increase was more significant in two ß-glucosidase-treated groups. Changes in odor activity values and odor spectrum values of key odorants indicated that the pectinase-treated sample had more prominent floral, green, and potato-like scents. In contrast, the ß-glucosidase-treated sample had more dominant floral, woody, almond-like, and fruity notes but less green odor, which was confirmed by sensory evaluation. ß-Glucosidase and pectinase complement one another very well, and together, promote a remarkable aroma enhancement in OF.

Efficacy of an improved method to screen semiochemicals of insect.

BACKGROUND: A combination of gas chromatography-electroantennographic detection (GC-EAD) and gas chromatography-mass spectrometry (GC-MS) is typically used to screen active compounds that play a role in the regulation of insect behavior. This method uses two kinds of gas chromatography (GC) equipment and needs to compare compounds between the two chromatograms, and it is tedious and costly. To improve detection efficiency, as well as reduce costs and the rate of missed detection, we designed a system connecting gas chromatography (GC), electroantennography (EAG), and mass spectrometry (MS), with MS used instead of the flame ionization detector (FID) as the GC-EAD detector. To verify the feasibility of the improved method, we compare two methods-GC-EAG-MS and GC-EAD-through a series of experiments. Some researchers made similar improvements, but these were not compared with GC-EAD, and their method needed to be improved in the synchronization and split ratio. Our method has been optimized and improved in these aspects. METHODS: Helicoverpa armigera was the test organism; the improved method and conventional method were used to detect known and unknown compounds, as well as screen out active compounds that could generate responses in H. armigera antennae. RESULTS: Screening known single compounds using the two methods, the active compound benzaldehyde was detected in all seven concentrations of solution. By using the two methods, the five same active compounds of Helicoverpa armigera were detected in high concentration solution of the mixed compounds (100 mg L-1, 50 mg L-1); the four same active compounds were detected at 20 mg L-1 concentration; two identical same compounds were detected in low concentration solution (concentrations of 10 mg L-1 and below). By using the two methods, six identical active compounds of Helicoverpa armigera were detected in unknown compounds. CONCLUSION: The improved method was consistent with the conventional method in terms of accuracy and sensitivity. However, compared with the traditional methods, Gas chromatography-electroantennographic-mass spectrometry (GC-EAG-MS) saved the cost of GC and FID equipment, thereby greatly lowering the experimental cost. In the experiment, GC-EAG-MS combined the two experimental operations of screening active substances by GC-EAD and identifying active substances by GC-MS into one, which not only reduced the experimental steps, but also avoided the false positive caused by the comparison of the two chromatograms, and it greatly reduced the difficulty level of the overall experimental analysis. GC-EAG-MS is more convenient, efficient, economical, and practical, and could confidently replace traditional methods. With further optimization, it could be widely applied in the study of plant and insect chemical ecology.