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IntroductionThere is a close and complex interaction between the elements in the aboveground-underground ecosystem during the growth and development of plants. Specifically, when the aboveground part of plants is infected by pathogens, it induces the plant rhizosphere to synthesize specific root exudates. Consequently, a group of beneficial rhizosphere soil bacteria is recruited to help plants resist diseases. However, the changes in the rhizosphere soil bacterial community of plants under infection by oomycete pathogens remain unknown.MethodsThree experimental treatments were set up in this experiment: soils inoculated with P. nicotianae, no-inoculation with P. nicotianae, and a control. The control treatment was composed of soils without transplanted tobacco plants, with the pathogen inoculated twice at an interval of eight days to ensure a successful P. nicotianae infection. P. nicotianae inoculation treatments were designed using the hyphal block inoculation method. In the non-inoculation treatment, tobacco plants were grown normally without pathogen inoculation. The tobacco plants were grown in a greenhouse.ResultsThis study demonstrates that tobacco plants recruit microorganisms at the rhizosphere level as a defense mechanism against disease after infection by the oomycete pathogen Phytophthora nicotianae. Specific rhizosphere soil bacteria were screened in vitro to promote tobacco growth in a biofilm-forming manner, which induced the systemic resistance of the plants to P. nicotianae. The recruitment of rhizosphere soil bacteria to the inter-root zone of tobacco plants after infection by P. nicotianae can help subsequently cultivated tobacco plants in the same soil resist pathogen infestation.DiscussionIn conclusion, the present study confirms that infestation caused by oomycete pathogens alters the composition of the plant rhizosphere soil bacterial community and recruits a specific group of beneficial microorganisms that induce disease resistance and promote plant growth, thereby maximizing the protection of progeny grown in the same soil against the disease.

【Objective】It is complex, time-consuming and laborious for conventional chemical detection method to detect the content of total nitrogen, potassium, total sugars, reducing sugars, total alkali, chlorine and magnesium in wrapper tobacco, while near-infrared spectroscopy technology is simple to operate and rapid to detect. The aims is to establish a near infrared spectroscopy detection model to achieve rapid quantitative analysis of the content of the seven chemical components in wrapper tobacco.【Method】Taking Yunnan cigar wrapper tobacco as the material, conventional chemical method was used to detect the content of seven chemical components in wrapper tobacco, and then near infrared spectroscopy was used to analyze the content of seven chemical components and their spectruml data of wrapper tobacco by using near infrared spectroscopy combined with partial least squares method, and the model with the optimal predictive performance was determined by comparing the root mean square error and correlation coefficient of the model.【Result】The optimal prediction results of the seven chemical components were established by the preprocessing methods of original spectrum, first derivative, first derivative, original spectrum, original spectrum, first derivative + median filtering and first derivative + median filtering, and the optimal principal component numbers were 20, 7, 4, 24, 21, 9 and 7, respectively; The training set correlation coefficients (r) of the seven models were 0.9441, 0.8589, 0.7664, 0.9511, 0.9547, 0.9031 and 0.8620, respectively. The root mean square error of cross validation (RMSECV) were 0.1288, 0.2846, 0.0280, 0.0096, 0.1894, 0.2965 and 0.0795; The correlation coefficients (r) of the validation set were 0.8958, 0.7675, 0.7181, 0.7928, 0.7282, 0.8062 and 0.7980, and the root mean square error of prediction (RMSEP) were 0.1789, 0.3011, 0.0324, 0.0193, 0.3855, 0.3990 and 0.0999. Moreover, the models were externally verified, and the results indicated that the average RSD of the predicted values and chemical values of the seven chemical components were less than 32%.【Conclusion】It was feasible to use near infrared spectroscopy to rapidly and quantitatively analyze the contents of seven chemical components in wrapper tobacco. The models had good prediction effect on the contents of seven chemical components, and could provide a reference for the rapidly and quantitatively analysis of seven chemical components in wrapper tobacco.

ObjectivesThe aim of this study was to analyze long-term outcomes of Chinese coronary artery disease (CAD) patients with (and without) chronic obstructive pulmonary disease (COPD) after percutaneous coronary intervention (PCI).BackgroundChronic obstructive pulmonary disease is a chronic condition which often develops in conjunction with CAD. PCI is a core therapy for CAD, although we still need to understand CAD-COPD outcomes and to identify factors that influence prognoses, across ethnicities.MethodsThis double-cohort study involved 12,343 Chinese CAD patients who received PCI. Baseline characteristics were collected in two independent, specialty centers. Propensity-score matching was performed to control confounding factors, using a nearest neighbor matching method within a 0.02 caliper and on a propensity score scale of 0.1 for each center. Comorbid CAD-COPD cases were compared to non-COPD patients in terms of major adverse cardiac events (MACEs).ResultsPatients with COPD were generally older than those without COPD (65.4 ± 9.2 vs. 58.2 ± 10.3, p < 0.001). There were no significant differences in the end points between COPD and non-COPD groups after PCI (All p > 0.05); however, the incidence of MACEs increased after 450 days. Further subgroup analysis suggests that COPD is approximately four times more prevalent among those aged over 75 years (HR, 3.818; 95%CI, 1.10–13.29; p = 0.027) and those aged below 55 years (HR = 4.254; 95% CI, 1.55–11.72; p = 0.003).ConclusionHaving COPD does not appear to have a significant impact on CAD outcomes 2 years after PCI, and beyond. However, an increasing number of MACEs was observed after 450 days, which suggests that there may be a double-stage effect of COPD on PCI prognosis. There is a need for focused comorbidity management, specifically for those aged below 55 years and above 75 years.

Background and ObjectiveIn amyotrophic lateral sclerosis (ALS), progressive weakness significantly limits the ability to exercise. However, measurements of the impaired exercise function and their practical value to assess disease progression in ALS are scarce. Cardiopulmonary exercise testing (CPET) is a non-invasive accurate method used to comprehensively quantify exercise physiology in a variety of diseases. This study aimed to evaluate the clinical value of CPET and to explore its association with disease severity and prognosis prediction in ALS.MethodsA total of 319 participants were enrolled in this 3-year prospective study. After strict quality control, 109 patients with ALS and 150 age- and sex-matched healthy controls were included with comprehensive clinical assessment and follow-ups. The incremental ramp protocol for symptom-limited CPET was applied in both groups. The exercise physiology during peak effort exercise was systematically measured, including the overall aerobic capacity of exercise (VO2 peak) and the respective capacity of the exercise-involved organs [cardiac response (heart rate peak—HR peak), ventilatory efficiency (VE/VCO2 slope), breathing economy (VE/VO2 peak), and other relevant parameters]. Disease severity and progression were evaluated using recognized scales. Survival was monitored with regular follow-ups every 6 months.ResultsDecreased exercise capacity (VO2 peak < 16 ml/kg/min) occurred more frequently in patients with ALS than in controls (44.95% vs. 9.33%, p < 0.01). In patients with ALS, the average VO2 peak (16.16 ± 5.43 ml/kg/min) and HR peak [135 (112–153) bpm] were significantly lower (p < 0.01) than in controls [22.26 ± 7.09 ml/kg/min; 148 (135–164) bpm], but the VE/VCO2 slope was significantly higher [28.05 (25.03–32.16) vs. 26.72 (24.37–29.58); p = 0.03]. In patients with ALS, the VO2 peak and HR peak were significantly correlated with disease severity and progression scores (p < 0.05). Survival analyses revealed the VO2 peak and HR peak as protective indicators while the VE/VO2 peak as a detrimental indicator for the prognostic prediction in ALS (HR = 0.839, p = 0.001; HR = 0.967, p < 0.001; HR = 1.137, p = 0.028, respectively).ConclusionOur prospective study quantified the significantly decreased exercise capacity in ALS through non-invasive CPET. The impaired VO2 peak and HR peak closely correlated with disease severity and independently predicted a worse prognosis. Our findings identified the clinical value of CPET as an objective indicator of disease progression in ALS.