Noninvasive Abiotic Stress Phenotyping of Vascular Plant in Each Vegetative Organ View

The last decades have witnessed a rapid development of noninvasive plant phenotyping, capable of detecting plant stress scale levels from the subcellular to the whole population scale. However, even with such a broad range, most phenotyping objects are often just concerned with leaves. This review offers a unique perspective of noninvasive plant stress phenotyping from a multi-organ view. First, plant sensing and responding to abiotic stress from the diverse vegetative organs (leaves, stems, and roots) and the interplays between these vital components are analyzed. Then, the corresponding noninvasive optical phenotyping techniques are also provided, which can prompt the practical implementation of appropriate noninvasive phenotyping techniques for each organ. Furthermore, we explore methods for analyzing compound stress situations, as field conditions frequently encompass multiple abiotic stressors. Thus, our work goes beyond the conventional approach of focusing solely on individual plant organs. The novel insights of the multi-organ, noninvasive phenotyping study provide a reference for testing hypotheses concerning the intricate dynamics of plant stress responses, as well as the potential interactive effects among various stressors.

Effects of micro-nano bubble water addition on maturation degree and microbial community during aerobic composting

In order to explore the effects of micro-nano bubble water (MNBW) on compost maturation and the microbial community in cow manure and straw during aerobic composting, we conducted composting tests using tap water with 12 mg/L (O12), 15 mg/L (O15), 18 mg/L (O18), and 21 mg/L (O21) dissolved oxygen in MNBW, as well as tap water with 9 mg/L dissolved oxygen as a control (CK). The results showed that O21 increased the maximum compost temperature to 64 °C, which was higher than the other treatments. All treatments met the harmless standards for compost. The seed germination index (GI) was largest under O21 and 15.1% higher than that under CK, and the non-toxic compost degree was higher. Redundancy analysis showed that the temperature, C/N, pH, and GI were important factors that affected the microbial community composition. The temperature, C/N, and pH were significantly positively correlated with Firmicutes and Actinobacteria (p < 0.05). Firmicutes was the dominant phylum in the mesophilic stage (2-6 days) and it accounted for a large proportion under O21, where the strong thermophilic metabolism increased the production of heat and prolonged the high temperature period. The bacterial genus Ammoniibacillus in Firmicutes accounted for a large proportion under O21 and it accelerated the decomposition of substrates. Therefore, the addition of MNBW changed the microbial community to affect the maturation of the compost, and the quality of the compost was higher under O21.

Diagnostic and prognostic value of parameters of erector spinae in patients with uremic sarcopenia

AIM

This study aimed to investigate whether computed tomography (CT)-measured erector spinae parameters (ESPs) have diagnostic, severity assessment, and prognostic predictive value in uremic sarcopenia (US).

MATERIALS AND METHODS

A total of 202 uremic patients were enrolled and divided into two groups: a control group and a sarcopenia group. Sarcopenia was classified into two types: severe and nonsevere. The area, volume, and density of the erector spinae (ES) were measured using chest CT images, and the relevant ESP, including the erector spinae index (ESI), total erector spinae volume (TESV), erector spinae density (ESD), and erector spinae gauge (ESG) were calculated. The occurrence of adverse events was followed-up for 36 months. The diagnostic value and severity of US were determined using the receiver operating characteristic (ROC) curve. Survival curves diagnosed using CT were plotted and compared with the curve drawn using the gold standard. Cox regression analysis was used to identify independent risk factors associated with survival in US.

RESULTS

With an area under the curve (AUC) of 0.840 and 0.739, the combined ESP has diagnostic value and the ability to assess the severity of US. There was no significant difference in the survival curve between the combined ESP for the diagnosis of US and the gold standard (P > 0.05). ESI is a standalone predictor of survival in patients with US.

CONCLUSION

ESP measured by CT has diagnostic values for US and its severity, as well as being a predictive value for the prognosis of US.

Early Detection of Rice Blast Using a Semi-Supervised Contrastive Unpaired Translation Iterative Network Based on UAV Images

Rice blast has caused major production losses in rice, and thus the early detection of rice blast plays a crucial role in global food security. In this study, a semi-supervised contrastive unpaired translation iterative network is specifically designed based on unmanned aerial vehicle (UAV) images for rice blast detection. It incorporates multiple critic contrastive unpaired translation networks to generate fake images with different disease levels through an iterative process of data augmentation. These generated fake images, along with real images, are then used to establish a detection network called RiceBlastYolo. Notably, the RiceBlastYolo model integrates an improved fpn and a general soft labeling approach. The results show that the detection precision of RiceBlastYolo is 99.51% under intersection over union (IOU0.5) conditions and the average precision is 98.75% under IOU0.5-0.9 conditions. The precision and recall rates are respectively 98.23% and 99.99%, which are higher than those of common detection models (YOLO, YOLACT, YOLACT++, Mask R-CNN, and Faster R-CNN). Additionally, external data also verified the ability of the model. The findings demonstrate that our proposed model can accurately identify rice blast under field-scale conditions.

Postoperative pulmonary complications in older patients undergoing elective surgery with a supraglottic airway device or tracheal intubation

The two most commonly used airway management techniques during general anaesthesia are supraglottic airway devices and tracheal tubes. In older patients undergoing elective non-cardiothoracic surgery under general anaesthesia with positive pressure ventilation, we hypothesised that a composite measure of in-hospital postoperative pulmonary complications would be less frequent when a supraglottic airway device was used compared with a tracheal tube. We studied patients aged ≥ 70 years in 17 clinical centres. Patients were allocated randomly to airway management with a supraglottic airway device or a tracheal tube. Between August 2016 and April 2020, 2900 patients were studied, of whom 2751 were included in the primary analysis (1387 with supraglottic airway device and 1364 with a tracheal tube). Pre-operatively, 2431 (88.4%) patients were estimated to have a postoperative pulmonary complication risk index of 1-2. Postoperative pulmonary complications, mostly coughing, occurred in 270 of 1387 patients (19.5%) allocated to a supraglottic airway device and 342 of 1364 patients (25.1%) assigned to a tracheal tube (absolute difference -5.6% (95%CI -8.7 to -2.5), risk ratio 0.78 (95%CI 0.67-0.89); p < 0.001). Among otherwise healthy older patients undergoing elective surgery under general anaesthesia with intra-operative positive pressure ventilation of their lungs, there were fewer postoperative pulmonary complications when the airway was managed with a supraglottic airway device compared with a tracheal tube.

Synchronously Predicting Tea Polyphenol and Epigallocatechin Gallate in Tea Leaves Using Fourier Transform-Near-Infrared Spectroscopy and Machine Learning

Tea polyphenol and epigallocatechin gallate (EGCG) were considered as key components of tea. The rapid prediction of these two components can be beneficial for tea quality control and product development for tea producers, breeders and consumers. This study aimed to develop reliable models for tea polyphenols and EGCG content prediction during the breeding process using Fourier Transform-near infrared (FT-NIR) spectroscopy combined with machine learning algorithms. Various spectral preprocessing methods including Savitzky-Golay smoothing (SG), standard normal variate (SNV), vector normalization (VN), multiplicative scatter correction (MSC) and first derivative (FD) were applied to improve the quality of the collected spectra. Partial least squares regression (PLSR) and least squares support vector regression (LS-SVR) were introduced to establish models for tea polyphenol and EGCG content prediction based on different preprocessed spectral data. Variable selection algorithms, including competitive adaptive reweighted sampling (CARS) and random forest (RF), were further utilized to identify key spectral bands to improve the efficiency of the models. The results demonstrate that the optimal model for tea polyphenols calibration was the LS-SVR with R_p = 0.975 and RPD = 4.540 based on SG-smoothed full spectra. For EGCG detection, the best model was the LS-SVR with R_p = 0.936 and RPD = 2.841 using full original spectra as model inputs. The application of variable selection algorithms further improved the predictive performance of the models. The LS-SVR model for tea polyphenols prediction with R_p = 0.978 and RPD = 4.833 used 30 CARS-selected variables, while the LS-SVR model build on 27 RF-selected variables achieved the best predictive ability with R_p = 0.944 and RPD = 3.049, respectively, for EGCG prediction. The results demonstrate a potential of FT-NIR spectroscopy combined with machine learning for the rapid screening of genotypes with high tea polyphenol and EGCG content in tea leaves.

High-throughput phenotyping salt tolerance in JUNCAOs by combining prompt chlorophyll a fluorescence with hyperspectral spectroscopy

The planting of salt-tolerant plants is regarded as the one of important measurements to improve the saline-alkali lands. The outstanding biological properties of JUNCAOs have made them candidates to improve and utilize saline-alkali lands. At present, little attention has been paid to developing a non-destructive and high throughput approach to evaluate the salt tolerance of JUNCAO. To close the gaps, three typical JUNCAOs (A.donax. No.1, A.donax. No.5 and A.donax. No.10) were evaluated by combining prompt chlorophyll a fluorescence (ChlF) with hyperspectral spectroscopy (HS). The results showed that salt stress reduced relative stem growth, water content, and total chlorophyll content but enhanced the malondialdehyde (MDA) content. It caused a significant change in chlorophyll a fluorescence kinetics with an appearance of L-, K- and J-band, implying damaging energetic connectivity between PSII units, uncoupling of the oxygen evolving complex (OEC) and inhibition of the Q_A^-reoxidation. The negative impact of salt stress on JUNCAOs increased with the increasing level of salt concentration. Effect on spectral reflectance in the in the visible region with shifts on red edge position (REP) and blue edge position (BEP) to shorter wavelength was also found in salt stress plants. Combining principal component analysis (PCA) with the membership function method based on spectral indices and JIP-test parameters could well screen JUNCAOs salt tolerant ability with the highest for A.donax. NO.10 but lowest for A.donax. NO.1, which was the same as that of using conventional approach. The results demonstrate that prompt ChlF coupling with HS could provide potentials for non-invasively and high-throughput phenotyping salt tolerance in JUNCAOs.

A Synthetic Review of Various Dimensions of Non-Destructive Plant Stress Phenotyping

Non-destructive plant stress phenotyping begins with traditional one-dimensional (1D) spectroscopy, followed by two-dimensional (2D) imaging, three-dimensional (3D) or even temporal-three-dimensional (T-3D), spectral-three-dimensional (S-3D), and temporal-spectral-three-dimensional (TS-3D) phenotyping, all of which are aimed at observing subtle changes in plants under stress. However, a comprehensive review that covers all these dimensional types of phenotyping, ordered in a spatial arrangement from 1D to 3D, as well as temporal and spectral dimensions, is lacking. In this review, we look back to the development of data-acquiring techniques for various dimensions of plant stress phenotyping (1D spectroscopy, 2D imaging, 3D phenotyping), as well as their corresponding data-analyzing pipelines (mathematical analysis, machine learning, or deep learning), and look forward to the trends and challenges of high-performance multi-dimension (integrated spatial, temporal, and spectral) phenotyping demands. We hope this article can serve as a reference for implementing various dimensions of non-destructive plant stress phenotyping.

Citrus Huanglongbing detection and semi-quantification of the carbohydrate concentration based on micro-FTIR spectroscopy

Citrus Huanglongbing (HLB) is nowadays one of the most fatal citrus diseases worldwide. Once the citrus tree is infected by the HLB disease, the biochemistry of the phloem region in midribs would change. In order to investigate the carbohydrate changes in phloem region of citrus midrib, the semi-quantification models were established to predict the carbohydrate concentration in it based on Fourier transform infrared microscopy (micro-FTIR) spectroscopy coupled with chemometrics. Healthy, asymptomatic-HLB, symptomatic-HLB, and nutrient-deficient citrus midribs were collected in this study. The results showed that the intensity of the characteristic peak varied with the carbohydrate (starch and soluble sugar) concentration in citrus midrib, especially at the fingerprint regions of 1175-900 cm^-1, 1500-1175 cm^-1, and 1800-1500 cm^-1. Furthermore, semi-quantitative prediction models of starch and soluble sugar were established using the full micro-FTIR spectra and selected characteristic wavebands. The least squares support vector machine regression (LS-SVR) model combined with the random frog (RF) algorithm achieved the best prediction result with the determination coefficient of prediction ([Formula: see text]) of 0.85, the root mean square error of prediction (RMSEP) of 0.36%, residual predictive deviation (RPD) of 2.54, and [Formula: see text] of 0.87, RMSEP of 0.37%, RPD of 2.76, for starch and soluble sugar concentration prediction, respectively. In addition, multi-layer perceptron (MLP) classification models were established to identify HLB disease, achieving the overall classification accuracy of 94% and 87%, based on the full-range spectra and the optimal wavenumbers selected by the random frog (RF) algorithm, respectively. The results demonstrated that micro-FTIR spectroscopy can be a valuable tool for the prediction of carbohydrate concentration in citrus midribs and the detection of HLB disease, which would provide useful guidelines to detect citrus HLB disease.

Optimal temporal-spatial fluorescence techniques for phenotyping nitrogen status in oilseed rape

Nitrogen (N) fertilizer maximizes the growth of oilseed rape (Brassica napus L.) by improving photosynthetic performance. Elucidating the dynamic relationship between fluorescence and plant N status could provide a non-destructive diagnosis of N status and the breeding of N-efficient cultivars. The aim of this study was to explore the impacts of different N treatments on photosynthesis at a spatial-temporal scale and to evaluate the performance of three fluorescence techniques for the diagnosis of N status. One-way ANOVA and linear discriminant analysis were applied to analyze fluorescence data acquired by a continuous excitation chlorophyll fluorimeter (OJIP transient analysis), pulse amplitude-modulated chlorophyll fluorescence (PAM-ChlF), and multicolor fluorescence (MCF) imaging. The results showed that the maximum quantum efficiency of PSII photochemistry (Fv/Fm) and performance index for photosynthesis (PIABS) of bottom leaves were sensitive to N status at the bolting stage, whereas the red fluorescence/far-red fluorescence ratio of top leaves was sensitive at the early seedling stage. Although the classification of N treatments by the three techniques achieved comparable accuracies, MCF imaging showed the best potential for early diagnosis of N status in field phenotyping because it had the highest sensitivity in the top leaves, at the early seedling stage. The findings of this study could facilitate research on N management and the breeding of N-efficient cultivars.

Chiral terahertz wave emission from the Weyl semimetal TaAs

Weyl semimetals host chiral fermions with distinct chiralities and spin textures. Optical excitations involving those chiral fermions can induce exotic carrier responses, and in turn lead to novel optical phenomena. Here, we discover strong coherent terahertz emission from Weyl semimetal TaAs, which is demonstrated as a unique broadband source of the chiral terahertz wave. The polarization control of the THz emission is achieved by tuning photoexcitation of ultrafast photocurrents via the photogalvanic effect. In the near-infrared regime, the photon-energy dependent nonthermal current due to the predominant circular photogalvanic effect can be attributed to the radical change of the band velocities when the chiral Weyl fermions are excited during selective optical transitions between the tilted anisotropic Weyl cones and the massive bulk bands. Our findings provide a design concept for creating chiral photon sources using quantum materials and open up new opportunities for developing ultrafast opto-electronics using Weyl physics.

Using hyperspectral analysis as a potential high throughput phenotyping tool in GWAS for protein content of rice quality

BACKGROUND

The advances of hyperspectral technology provide a new analytic means to decrease the gap of phenomics and genomics caused by the fast development of plant genomics with the next generation sequencing technology. Through hyperspectral technology, it is possible to phenotype the biochemical attributes of rice seeds and use the data for GWAS.

RESULTS

The results of correlation analysis indicated that Normalized Difference Spectral Index (NDSI) had high correlation with protein content (PC) with RNDSI 2 = 0.68. Based on GWAS analysis using all the traits, NDSI was able to identify the same SNP loci as rice protein content that was measured by traditional methods. In total, hyperspectral trait NDSI identified all the 43 genes that were identified by biochemical trait PC. NDSI identified 1 extra SNP marker on chromosome 1, which annotated extra 22 genes that were not identified by PC. Kegg annotation results showed that traits NDSI annotated 3 pathways that are exactly the same as PC. The cysteine and methionine metabolic pathway identified by both NDSI and PC was reported important for biosynthesis and metabolism of some of amino acids/protein in rice seeds.

CONCLUSION

This study combined hyperspectral technology and GWAS analysis to dissect PC of rice seeds, which was high throughput and proven to be able to apply to GWAS as a new phenotyping tool. It provided a new means to phenotype one of the important biochemical traits for the determination of rice quality that could be used for genetic studies.

Rapid detection of cadmium and its distribution in Miscanthus sacchariflorus based on visible and near-infrared hyperspectral imaging

Monitoring the effectiveness of Miscanthus sacchariflorus to meet the basic requirements for environmental remediation projects is an important step in determining its use as a productive bioenergy crop for phytoremediation. Conventional chemical methods for the determination of cadmium (Cd) contents involve time-consuming, monotonous and destructive procedures and are not suitable for high-throughput screening. In the present study, visible and near-infrared hyperspectral imaging technology combined with chemometric methods was used to assess the Cd concentrations in M. sacchariflorus. The total Cd concentrations in different plant tissues were measured using an inductively coupled plasma-mass spectrometer. Partial least-squares regression and least-squares support vector machine were implemented to estimate Cd contents from spectral reflectance. Successive projections algorithm and competitive adaptive reweighted sampling (CARS) methodology were used for selecting optimal wavelength. The CARS-partial least-squares regression model resulted in the most accurate predictions of Cd contents in M. sacchariflorus leaves, with a determination coefficient (R²) of 0.87 and a root mean square error (RMSE) value of 97.78 for the calibration set, and an R² value of 0.91 and a RMSE value of 75.95 for the prediction set. The CARS-least-squares support vector machine model resulted in the most satisfactory predictions of Cd contents in roots, with R² values of 0.95 (RMSE, 0.92 × 10³) for the calibration set and 0.90 (RMSE, 1.64 × 10³) for the prediction set. Finally, the Cd concentrations in different plant tissues were visualized on the prediction maps by predicted spectral features on each hyperspectral image pixel. Thus, visible and near-infrared imaging combined with chemometric methods produces a promising technique to evaluate M. sacchariflorus' Cd phytoremediation capability in high-throughput metal-contaminated field applications.

Dynamic monitoring of biomass of rice under different nitrogen treatments using a lightweight UAV with dual image-frame snapshot cameras

BACKGROUND

Unmanned aerial vehicle (UAV)-based remote sensing provides a flexible, low-cost, and efficient approach to monitor crop growth status at fine spatial and temporal resolutions, and has a high potential to accelerate breeding process and improve precision field management.

METHOD

In this study, we discussed the use of lightweight UAV with dual image-frame snapshot cameras to estimate aboveground biomass (AGB) and panicle biomass (PB) of rice at different growth stages with different nitrogen (N) treatments. The spatial-temporal variations in the typical vegetation indices (VIs) and AGB were first investigated, and the accuracy of crop surface model (CSM) extracted from the Red Green Blue (RGB) images at two different stages were also evaluated. Random forest (RF) model for AGB estimation as well as the PB was then developed. Furthermore, variable importance and sensitivity analysis of UAV variables were performed to study the potential of improving model robustness and prediction accuracies.

RESULTS

It was found that the canopy height extracted from the CSM (Hcsm) exhibited a high correlation with the ground-measured canopy height, while it was unsuitable to be independently used for biomass assessment of rice during the entire growth stages. We also observed that several VIs were highly correlated with AGB, and the modified normalized difference spectral index extracted from the multispectral image achieved the highest correlation. RF model with fusing RGB and multispectral image data substantially improved the prediction results of AGB and PB with the prediction of root mean square error (RMSEP) reduced by 8.33-16.00%. The best prediction results for AGB and PB were achieved with the coefficient of determination (r2), the RMSEP and relative RMSE (RRMSE) of 0.90, 0.21 kg/m2 and 14.05%, and 0.68, 0.10 kg/m2 and 12.11%, respectively. In addition, the result confirmed that the sensitivity analysis could simplify the prediction model without reducing the prediction accuracy.

CONCLUSION

These findings demonstrate the feasibility of applying lightweight UAV with dual image-frame snapshot cameras for rice biomass estimation, and its potential for high throughput analysis of plant growth-related traits in precision agriculture as well as the advanced breeding program.

[Analysis of 9 cases of nodular type of pulmonary cryptococcosis with coexisting lung cancer confirmed by pathological examinations]

Objective: To describe the characteristics of the nodular type of pulmonary cryptococcosis (PC) with coexisting lung cancer. Methods: A total of 9 cases of PC with coexisting lung cancer, admitted to Fuzhou Pulmonary Hospital of Fujian from 1st January 2009 to 31th December 2016, and confirmed by pathological examinations, were studied and the related literature were reviewed. Results: The patients consisted of 1 male and 8 females, with a mean age of (53±10) years (range, 38 to 68 years). Four patients (44.4%) had underlying diseases, 3 with diabetes mellitus and 1 with gastric cancer surgery. The main clinical manifestations of most cases were cough and phlegm. The lesions of PC on chest CT were mostly solitary or multiple nodules with a diameter < 1 cm, and the lesions of carcinoma were shown as solitary nodules with a variety of signs suggestive of malignancy. All the patients were confirmed to have concomitant PC and lung adenocarcinoma by pathological examinations. Lung cancer stage was early (Tis and Ⅰ-Ⅱ) in 88.9 % (8 cases) of the cases. All the patients received surgery and postoperative medical therapy. The prognosis was relatively good in most of them except 1 case with death due to lung cancer metastasis and 1 case with lung cancer recurrence. Conclusions: Coexistence of PC and lung cancer is rare and the clinical symptoms are not specific. When PC coexists with carcinoma and manifests as pulmonary nodule, it mimics malignant lesions and is extremely easy to be misdiagnosed. Therefore PC must be considered in the differential diagnosis of pulmonary nodules.

[Endoscopicretrograde cholangio-pancreatography management of long-term complications after pancreaticoduodenectomy]

Objective: To investigate the feasibility and effectiveness of endoscopicretrograde cholangio-pancreatography(ERCP)in the management of long-term complications after pancreaticoduodenectomy. Methods: From January 2009 to July 2018, the clinical data of 62 patients with biliary or pancreatic long-term complications after pancreatoduodenectomy were reviewed at Department of General Surgery, and the corresponding ERCP were carried out in the multi-disciplinary cooperation.There were 39 males and 24 females.The age was 56.5 years(aging from 13 to 76 years). The time of treatment was 3 months to 20 years after pancreatoduodenectomy.The long-term biliopancreatic complications after pancreatoduodenectomy included 51 cases of biliary calculi, 42 cases of bilioenteric anastomotic stenosis with proximal bile duct dilatation, and 11 cases of pancreaticointestinal anastomosis stenosis with distal pancreatic duct dilatation.All patients received conventional duodenoscopy or single-balloon enteroscopy assisted ERCP under general anesthesia. Results: A total of 95 ERCP were performed in 62 patients, averaging 1.5 times per case.The long-term complications of cholangiopancreatic after pancreatoduodenectomy(ERCP indications) included 56 times of bile duct stones(58.9%), 45 times of bilioenteric anastomatic stricture(47.4%), 11 times of recurrent pancreatitis(11.6%), 6 cases(6.3%) of bilioenteric anastomatic foreign body, 3 times of intrahepatic bile duct stenosis(3.2%). Among the 95 times, 82 times(86.3%) achieved endoscopic endoscopy, 76 times(80.0%) were diagnosed successfully, and 72 times(75.8%) were successfully treated with ERCP.Small intestinal perforation occurred in 1 patient undergoing duodenoscopy, and then healed by surgical repair. Conclusion: Multi-disciplinary collaboration of ERCP is safe and effective in the treatment of long-term complications after pancreaticoduodenectomy, but the long-term effect still needs further clinical follow-up.

Phenotyping of Arabidopsis Drought Stress Response Using Kinetic Chlorophyll Fluorescence and Multicolor Fluorescence Imaging

Plant responses to drought stress are complex due to various mechanisms of drought avoidance and tolerance to maintain growth. Traditional plant phenotyping methods are labor-intensive, time-consuming, and subjective. Plant phenotyping by integrating kinetic chlorophyll fluorescence with multicolor fluorescence imaging can acquire plant morphological, physiological, and pathological traits related to photosynthesis as well as its secondary metabolites, which will provide a new means to promote the progress of breeding for drought tolerant accessions and gain economic benefit for global agriculture production. Combination of kinetic chlorophyll fluorescence and multicolor fluorescence imaging proved to be efficient for the early detection of drought stress responses in the Arabidopsis ecotype Col-0 and one of its most affected mutants called reduced hyperosmolality-induced [Ca2+]i increase 1. Kinetic chlorophyll fluorescence curves were useful for understanding the drought tolerance mechanism of Arabidopsis. Conventional fluorescence parameters provided qualitative information related to drought stress responses in different genotypes, and the corresponding images showed spatial heterogeneities of drought stress responses within the leaf and the canopy levels. Fluorescence parameters selected by sequential forward selection presented high correlations with physiological traits but not morphological traits. The optimal fluorescence traits combined with the support vector machine resulted in good classification accuracies of 93.3 and 99.1% for classifying the control plants from the drought-stressed ones with 3 and 7 days treatments, respectively. The results demonstrated that the combination of kinetic chlorophyll fluorescence and multicolor fluorescence imaging with the machine learning technique was capable of providing comprehensive information of drought stress effects on the photosynthesis and the secondary metabolisms. It is a promising phenotyping technique that allows early detection of plant drought stress.

Minimizing the Sample Sizes of Clinical Trials on Preclinical and Early Symptomatic Stage of Alzheimer Disease

BACKGROUND

Clinical trials of investigational drugs for Alzheimer disease (AD) increasingly focus on the prodromal (symptomatic) stage of the illness and now its preclinical (asymptomatic) stage. Sensitive and specific cognitive and functional endpoints are needed to track subtle cognitive and functional changes in the early and preclinical stages to minimize sample sizes in these trials.

OBJECTIVES

To identify informative items in a standard clinical assessment protocol and a psychometric battery that are predictive of onset of dementia symptom.

DESIGN

Longitudinal retrospective study.

SETTING

Washington University (WU) Knight Alzheimer Disease Research Center (ADRC).

PARTICIPANTS

A total of 735 individuals at least 65 years old and cognitively normal at baseline from a longitudinal clinical cohort at the WU Knight ADRC.

MEASUREMENTS

The annual clinical assessment included a wide spectrum of functional and cognitive domains; a comprehensive psychometric battery was completed about 2 weeks after the clinical evaluation. Psychometricians are blinded to the results of the clinical evaluation and to the prior performance of the participants on the psychometric tests.

RESULTS

The mean age at baseline of the 735 participants was 74.30 and 62.31% were female. 240 individuals developed prodromal dementia symptoms (consistent with mild cognitive impairment due to AD and with very mild AD dementia) during longitudinal follow-up (mean follow-up=6.79 years). Among a total of 562 items in the clinical and cognitive assessments under analysis, 292 (52%) were identified as informative because their longitudinal changes were predictive of symptomatic onset. When these items were used to form the functional and cognitive composites, the longitudinal rates of changes were free of a learning effect and captured subtle longitudinal progression prior to symptomatic onset. The rates of change were much greater right after the symptomatic onset than those from the functional and cognitive composites formed using non-informative items. Although the sample sizes for prevention trials (prior to symptomatic onset) using the informative items still yield large numbers, the sample sizes for early treatment trial (after symptomatic onset) was much smaller than those derived from all the items or from the non-informative items alone.

CONCLUSIONS

The antecedent longitudinal changes in nearly half of the items in a clinical assessment protocol and a comprehensive cognitive battery did not show statistically significant ability to predict the dementia symptom onset, and hence may be non-informative to track the preclinical functional and cognitive progression of AD. The remaining items, on the other hand, captured some of the preclinical changes prior to the symptom onset, but performed much better right after the symptom onset. Currently ongoing prevention trials on preclinical AD of elderly individuals may need to re-assess the sample sizes and statistical power.

[Choice of genetic model on Meta-analysis of genetic association studies: introduction of genetic model-free approach for Bayesian analysis]

Meta-analysis used for genetic association studies became popular among researchers, with the amount of published papers increased rapidly. In this paper, we will focus on the introduction on the selection of genetic models. Traditionally, methods used for Meta-analysis on genetic association studies was to calculate the statistics based on available genetic models which not only increasing the probability of false-positives but also making the interpretation of results more difficult. Hence, a critical step in the Meta-analysis of genetic association studies was to choose the appropriate inheritance model. The aim of this paper was to introduce the theory of Bayesian analysis regarding the genetic model-free approach, in performing the Meta-analysis for studies related to genetic associations.

Lipopolysaccharides Trigger Two Successive Bursts of Reactive Oxygen Species at Distinct Cellular Locations

Lipopolysaccharides (LPS) are major components of the outer membrane of gram-negative bacteria and are an important microbe-associated molecular pattern (MAMP) that triggers immune responses in plants and animals. A previous genetic screen in Arabidopsis (Arabidopsis thaliana) identified LIPOOLIGOSACCHARIDE-SPECIFIC REDUCED ELICITATION (LORE), a B-type lectin S-domain receptor kinase, as a sensor of LPS. However, the LPS-activated LORE signaling pathway and associated immune responses remain largely unknown. In this study, we found that LPS trigger biphasic production of reactive oxygen species (ROS) in Arabidopsis. The first transient ROS burst was similar to that induced by another MAMP, flagellin, whereas the second long-lasting burst was induced only by LPS. The LPS-triggered second ROS burst was found to be conserved in a variety of plant species. Microscopic observation of the generation of ROS revealed that the LPS-triggered second ROS burst was largely associated with chloroplasts, and functional chloroplasts were indispensable for this response. The lipid A moiety, the most conserved portion of LPS, appears to be responsible for the second ROS burst. Surprisingly, the LPS- and lipid A-triggered second ROS burst was only partially dependent on LORE. Together, our findings provide insight on the LPS-triggered ROS production and the associated signaling pathway.

[Clinical application and evaluation of an early non-sedation protocol for critically ill respiratory patients]

Objective: To study the value of an early (mechanical ventilation after 24 h) non-sedation protocol for intubated, mechanically ventilated patients in the respiratory intensive care unit (RICU). Methods: Seventy intubated, mechanically ventilated patients were prospectively enrolled and randomly assigned to management with early non-sedation (intervention group; n=35) or with daily interruption of sedation (DIS) (control group; n=35). The duration of mechanical ventilation, length of the RICU and hospital stay, RICU and hospital mortality, drug consumption, RICU and hospitalization expenses, incidence of complications and adverse events and serum levels of vital organ damage and inflammatory markers after mechanical ventilation for 48 h were recorded and compared. Results: Patients in the intervention group had a shorter duration of mechanical ventilation than those in the control group [(7±5) vs (11±9) d, P<0.05] and were discharged from the RICU [(9±7) vs (18±9) d, P<0.05] and hospital earlier [(17±14) vs (29±22) d, P<0.05] than those in the control group. The doses of midazolam were significantly lower in the intervention group than in the control group [(99±104) vs (482±337) mg, P<0.05]. The RICU and hospitalization expenses were both significantly lower in the intervention group than in the control group [53(84) vs 88(173), 72(195) vs 154(234) thousand CHY, P<0.05]. In the intervention group, the occurrence rates of ventilator associated pneumonia (23% vs 46%), tracheotomy (14% vs 37%) and gastrointestinal adverse reactions (17% vs 40%) were significantly lower than those in the control group (P<0.05). No differences were recorded in RICU and hospital mortality (P>0.05). The occurrence rates of unplanned extubation and reintubation and the need for CT brain scans were similar in the 2 groups (P>0.05). The levels of cardiac, liver and renal damage markers, lactic acid and C-reactive protein were the same in both groups (P>0.05). Conclusions: The early non-sedation protocol decreased the duration of mechanical ventilation and the length of stay in the RICU and hospital, and it did not increase the incidence of complications and adverse events.

[Retrospective analysis of 117 cases of pulmonary cryptococcosis]

The clinical symptoms of PC were diverse and nonspecific. Halo sign and proximal air bronchogram are helpful for the diagnosis of PC. The outcome of most patients was satisfactory after appropriate treatment.

Chlorophyll Fluorescence Imaging Uncovers Photosynthetic Fingerprint of Citrus Huanglongbing

Huanglongbing (HLB) is one of the most destructive diseases of citrus, which has posed a serious threat to the global citrus production. This research was aimed to explore the use of chlorophyll fluorescence imaging combined with feature selection to characterize and detect the HLB disease. Chlorophyll fluorescence images of citrus leaf samples were measured by an in-house chlorophyll fluorescence imaging system. The commonly used chlorophyll fluorescence parameters provided the first screening of HLB disease. To further explore the photosynthetic fingerprint of HLB infected leaves, three feature selection methods combined with the supervised classifiers were employed to identify the unique fluorescence signature of HLB and perform the three-class classification (i.e., healthy, HLB infected, and nutrient deficient leaves). Unlike the commonly used fluorescence parameters, this novel data-driven approach by using the combination of the mean fluorescence parameters and image features gave the best classification performance with the accuracy of 97%, and presented a better interpretation for the spatial heterogeneity of photochemical and non-photochemical components in HLB infected citrus leaves. These results imply the potential of the proposed approach for the citrus HLB disease diagnosis, and also provide a valuable insight for the photosynthetic response to the HLB disease.

Early development of gonads in Muscovy duck embryos

Characteristics of gonadal development were investigated in Muscovy duck embryos at various embryonic ages. Hematoxylin-Eosin and periodic acid-Schiff staining were used to identify primordial germ cells, oogonia and sustentacular cells. Gene specific primers were designed based on conserved regions of duck antimullerian hormone (AMH), oestrogen receptor-α (ESR-α), doublesex and Mab-3 related transcription factor-1(DMRT1) and W chromosome protein kinase C inhibitor/interacting gene (WPKCI). Quantitative real-time polymerase chain reaction was used to characterise gene expression during gonad development in Muscovy duck embryos. Histology indicated that ovarian and testicular cells of Muscovy duck embryos developed on d 9 and 10. Immunohistochemistry showed that mouse vasa homologue-positive cells as well as Glial cell line-derived neurotrophic factor-positive cells increased significantly more in females than in males between d 9 and 10. AMH and ESR-α expression increased significantly during early development. DMRT1 acts prior to and during testis differentiation whereas WPKCI was expressed actively in the female Muscovy duck embryo before the onset of gonadal differentiation. Gonad development in Muscovy duck embryo was associated with several genes that were expressed before morphological features appear and were gender specific.

Efficacy of drug-eluting stent for chronic total coronary occlusions at different follow-up duration: a systematic review and meta-analysis

OBJECTIVE

DESs have been proved to be beneficial for patients with chronic total coronary occlusions (CTO) in terms of cardiac function and other prognosis. We aim to compare the efficacy and safety of drug-eluting stent (DES) and bare-metal stent (BMS) in CTO recanalization at different follow-up duration.

METHODS

Articles comparing outcomes between DES and BMS implantation in patients with CTO was searched. A fixed-effect (inverse-variance weighted) and random-effect (DerSimonian and Laird) model were used to analyze the pooling results.

RESULTS

A total of 29 comparative studies including 24 cohort studies and 5 randomized controlled studies were identified with a total of 9140 patients (5008 received BMS and 4132 received DES). The risk of all cause death for DES was higher at 6 months and lower at 12 months than BMS, and no significant difference was shown at 24, 36 and 60 months. DES group had lower risk of MI after 12 months implantation, and no difference was shown at 6, 24, 36 and 60 months. Major adverse cardiovascular event (MACE)-free survival was clinically and significantly improved by 73%, 68%, 49%, 40% and 37% respectively in DES group at 6,12, 24, 36, and 60 months.

CONCLUSIONS

DES is superior to BMS in binary restenosis, reocclusion and MACE-free survival during long-term follow up. The occurrences of all-cause death and MI show that the risk rate of BMS is higher than that of DES at 12 months. The frequency of all-cause death of DES is higher than BMS at 6 months. DES has higher risk of in-stent thrombosis than BMS at 36 months of implantation.

Ethyl pyruvate administration suppresses growth and invasion of gallbladder cancer cells via downregulation of HMGB1-RAGE axis

High mobility group box B1 (HMGB1)-receptor for advanced glycation end products (RAGE) axis has been previously known to be involved in carcinogenesis and development of multiple malignancies. Some studies have confirmed that Ethyl pyruvate (EP), a potent inhibitor of HMGB1, exerts the therapeutic effects on metastatic live tumor from gastric cancer. However, the effects and possible molecular mechanisms of EP on gallbladder cancer (GBC) need to be further explored. In the present study, human GBC cell lines (GBC-SD and SGC-996) were treated with different concentrations of EP. Then, the expression levels of HMGB1, RAGE and some transcription factors were identified by Real-time PCR and Western blot assays. Cell proliferative activities indicated by MTT assay, invasive potential by Transwell assay and cell apoptosis and cycle distribution were performed for functional analysis of GBC cell lines in vitro. As a result, EP decreased the expression of HMGB11, RAGE, PCNA and matrix metallopeptidase-9 (MMP-9), while it increased the expression of p53. Moreover, EP administration decreased GBC cell proliferation, inhibited the invasive potential, and induced apoptosis and cycle arrest in S phase in GBC cells. In conclusion, EP administration inhibits growth and invasion of gallbladder cancer cells possibly via down-regulation of the HMGB1-RAGE axis, suggesting that EP may play a critical role in the treatment of cancer in conjunction with other therapeutic agents.

[Histological changes in 20 hepatic fibrosis patients with chronic hepatitis B after recombinant human interferon-gamma treatment]

OBJECTIVE

To observe histological changes of hepatic fibrosis patients with chronic hepatitis B after recombinant human interferon-gamma treatment.

METHODS

Twenty hepatic fibrosis patients with chronic hepatitis B received rhIFN-gamma treatment at the dose of 1 MU intramuscularly daily for the first three months and every other day for the next six months. Liver biopsy was performed at the start of the therapy and the end of 9-month follow-up period respectively in all patients. All liver biopsy specimens were stained with hematoxylin-eosin and picro-sirius red. Modified Scheuer and Chevallier semi-quantitative scoring system was used to assess the results. In the meantime, serum hepatic fibrosis indices and serum biochemical examination were detected.

RESULTS

After 9 moths of treatment, the mean fibrosis score decreased from 11.24 +/- 5.34 to 8.67 +/- 4.16 (P<0.01), whereas the mean inflammation score decreased from 12.78 +/- 5.19 to 6.57 +/- 2.95 (P<0.01).

CONCLUSIONS

rhIFN-gamma showes a beneficial effect on hepatic fibrosis patients with chronic hepatitis B.

[Determination and significance of serum markers for fibrosis in patients with chronic hepatitis]

OBJECTIVE

To find the relationship between serum levels of hyaluronic acid (HA), type III procollagen (PC III), laminin (LN), type IV collagen (IV-C) and hepatic fibrosis as well as to determine their value in clinical practice.

METHODS

2600 serum samples from chronic hepatitis patients were tested with RIA for fibrosis indexes assays including HA, PC III, LN and IV-C. 280 of the patients with serum samples taken had liver biopsy performed and the biopsy material was examine pathomorphologically. Fibrosis indexes were compared according to inflammation grade, fibrosis stage and chronic hepatitis degree.

RESULTS

In the 2600 serum samples from chronic hepatitis patients, fibrosis indexes (including HA, PC III, LN and IV-C) had significant correlation with inflammation grade, fibrosis stage and the degree of chronic hepatitis (P < 0.01). The relating indexes to HA were 0.544, 0.548, 0.468 respectively, to PC III 0.495, 0.424, 0.335 respectively, to LN 0.214, 0.204, 0.184 and to IV-C were 0.464, 0.404, 0.412 respectively.

CONCLUSION

Serum fibrosis indexes are fairly well correlated with the inflammation grade, fibrosis stage and the degree of chronic hepatitis. However, as diagnostic markers, they must be combined with liver function, ultrasonography and clinical features.

Moloney murine leukemia virus long terminal repeat activates monocyte chemotactic protein-1 protein expression and chemotactic activity

Moloney murine leukemia virus (Mo-MuLV) is a thymotropic and leukemogenic retrovirus which causes T lymphomas. Recently, Mo-MuLV has been shown to trans-activate cellular genes. Monocyte chemoattractant protein-1 (MCP-1) is a chemokine which can promote the migration and diapedesis of monocytes and lymphocytes, as well as inducing metastasis of lymphomas. Here we demonstrate that introduction of Mo-MuLV or the MuLV LTR alone, transiently or stably, into Balb/c-3T3 cells or HeLa cells resulted in 9-11 fold increases in MCP-1 transcripts. This trans-activation of the MCP-1 gene by the Mo-MuLV LTR is independent of the physical location of the MCP-1 gene or of the LTR, occurring whether the LTR or the MCP-1 gene is integrated in the genome or transiently expressed. Immunoblot analysis using an anti-MCP-1 polyclonal antibody showed that the expression of the MuLV LTR in HeLa cells also induced the appearance of the MCP-1 protein. Boyden Chamber analysis demonstrated that the MCP-1 chemotactic activity produced by HeLa cells with an integrated MuLV LTR was elevated by 11 fold and that neutralizing antibody to human MCP-1 abrogated monocyte migration in response to MuLV LTR expression. Promoter deletional analysis showed the LTR responsive cis-acting element in the MCP-1 promoter is located between -141 and -88. Deletion of this region abolished the trans-activation of MCP-1 by the LTR. These LTR-mediated activations of a chemotactic and inflammatory cytokine may be relevant as mechanisms whereby retroviruses which do not contain oncogenes can induce neoplasia.

Activation of collagenase IV gene expression and enzymatic activity by the Moloney murine leukemia virus long terminal repeat

Moloney murine leukemia virus (Mo-MuLV) is a thymotropic and leukemogenic retrovirus which causes T lymphomas and leukemias, yet does not contain a transforming gene product. Mo-MuLV has been shown to trans-activate cellular genes via a polymerase III-generated transcript, designated let, from the long terminal repeat (LTR). Here we demonstrate that introduction of the Mo-MuLV LTR stably, or transiently, into murine or human cultured cells resulted in an 8- to 15-fold increase in collagenase IV (92-kDa gelatinase, gelatinase B, matrix metalloproteinase-9) gene expression. Collagenase IV protein expression was induced 9-fold by stable integration of MuLV LTR, as measured by immunoblot analysis using an anti-collagenase IV polyclonal antibody. The MuLV LTR coordinately stimulated the proteolytic activity of collagenase IV by 14-fold. The AP-1-binding site in the collagenase IV promoter was required for transactivation by the LTR. Collagenase type IV degrades type IV collagen, a major component of basement membrane, which constitutes the first step of the metastatic cascade. The activation of proteolytic enzymes by the MuLV LTR may thus play a contributory role in the development or spread of virus-induced lymphomas or leukemias.

The Moloney leukemia retroviral long terminal repeat trans-activates AP-1-inducible genes and AP-1 transcription factor binding

Moloney murine leukemia virus (Mo-MuLV) is a thymotropic and leukemogenic retrovirus which causes T lymphomas. The long terminal repeat (LTR) of Mo-MuLV affects the regulation of a number of cellular genes, including collagenase IV, monocyte chemoattractant protein-1, and c-jun genes, all of which contain 12-O-tetradecanoylphorbol-13-acetate-responsive element consensus sites within their promoters. We report here that Mo-MuLV stimulates the collagenase IV gene through transcription factor AP-1, and that the expression of a subgenomic portion of Mo-MuLV LTR alone is sufficient for this effect. Transient or stable expression of the viral LTR increases cellular AP-1 DNA binding activity. The collagenase IV 12-O-tetradecanoylphorbol-13-acetate-responsive element consensus sequence was shown to be required for this trans-activation. Deletions or mutations of this consensus site which abolished AP-1 binding also abolished trans-activation by the LTR. Transient or stable transfection of the viral LTR into cells stimulated c-jun gene expression, suggesting one mechanism whereby the viral LTR may induce cellular AP-1 activity. Thus, the Mo-MuLV LTR, through activation of the transcription factor AP-1, is capable of regulating cellular gene expression, including the induction of proto-oncogenes. This activity may be relevant to the mechanisms whereby retroviruses which do not contain oncogenes induce neoplasia.

Platelet-derived growth factor (PDGF) induction of egr-1 is independent of PDGF receptor autophosphorylation on tyrosine

Autophosphorylation of the platelet-derived growth factor (PDGF) receptor on tyrosine, which is dependent upon and occurs immediately after ligand binding, has been linked to the activation of second messenger pathways thought to be necessary for the induction of gene expression, DNA synthesis, and mitogenesis. We have investigated PDGF signal transduction in Balb/c3T3 and NIH-3T3 cells at the level of immediate-early gene induction under three conditions in which PDGF receptor autophosphorylation in response to PDGF binding is blocked: cells transformed by v-rasKi, cells transformed by v-mos, and cells treated with genistein, a specific inhibitor of tyrosine kinases. PDGF induction of immediate-early genes c-myc, c-fos, and JE is blocked in these systems. Induction of another immediate-early gene, egr-1, occurs normally despite the absence of measurable tyrosine kinase activity. The same results were obtained when cells were stimulated with PDGF-AA or PDGF-BB. It is not yet clear if this receptor tyrosine kinase-independent signal utilizes known PDGF second messengers, but these results demonstrate a new arm of the PDGF signal transduction pathway which operates in the absence of, and independently from, autophosphorylation of the receptor on tyrosine.