bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and Validation of a Personalized Survival Prediction Model for Uterine Adenosarcoma: A Population-Based Deep Learning Study
Authors: Qu Wenjie , Liu Qingqing , Jiao Xinlin , Zhang Teng , Wang Bingyu , Li Ningfeng , Dong Taotao , Cui Baoxia
Published: February 2021

Background

The aim was to develop a personalized survival prediction deep learning model for adenosarcoma patients using the surveillance, epidemiology and end results (SEER) database.

Methods

A total of 797 uterine adenosarcoma patients were enrolled in this study. Duplicated and useless variables were excluded, and 15 variables were selected for further analyses, including age, grade, positive lymph nodes or not, marital status, race, tumor extension, stage, and surgery or not. We created our deep survival learning (DSL) model to manipulate the data, which was randomly split into a training set (n = 519, 65%), validation set (n = 143, 18%) and testing set (n = 143, 18%). The Cox proportional hazard (CPH) model was also included comparatively. Finally, personalized survival curves were plotted for randomly selected patients.

Results

The c-index for the CPH model was 0.726, and the Brier score was 0.17. For our deep survival learning model, we achieved a c-index of 0.774 and a Brier score of 0.14 in the external testing set. In addition, the limitations of the traditional staging system were revealed, and a personalized survival prediction system based on our risk scoring grouping was developed.

Conclusions

Our study developed a deep neural network model for adenosarcoma. The performance of this model was superior to that of the traditional Cox proportional hazard model. In addition, a personalized survival prediction system was developed based on our deep survival learning model, which provided more accurate prognostic information for adenosarcoma patients.
Daratumumab for the Management of Newly Diagnosed and Relapsed/Refractory Multiple Myeloma: Current and Emerging Treatments
Authors: Offidani Massimo , Corvatta Laura , Morè Sonia , Nappi Davide , Martinelli Giovanni , Olivieri Attilio , Cerchione Claudio
Published: February 2021

Immunotherapy is changing the paradigm of multiple myeloma (MM) management and daratumumab is the first-in-class human monoclonal antibody targeting CD38 approved for the treatment of this malignancy. Daratumumab exerts anti-myeloma activity by different mechanisms of action as antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP), complement-dependent cytotoxicity (CDC), direct apoptosis, and immunomodulation. After GEN501 and SIRIUS trials showed efficacy of daratumumab monotherapy in heavily pretreated relapsed-refractory multiple myeloma (RRMM), in patients with at least two previous line of therapy, two phase III trials demonstrated superior overall response rate (ORR) and progression free survival (PFS) using triplets daratumumab–bortezomib–dexamethasone (DVd) vs Vd (CASTOR) or daratumumab–lenalidomide–dexamethasone (DRd) vs Rd (POLLUX) in relapsed-refractory MM patients; so these combinations have been approved and introduced in clinical practice. The ongoing phase III CANDOR is evaluating the triplet daratumumab–carfilzomib–dexamethasone (DKd) vs Kd whereas phase III APOLLO trial is exploring daratumumab–pomalidomide–dexamethasone (DPd) vs PD. Many other trials exploring daratumumab combinations in relapsed-refractory MM are ongoing, and they will provide other interesting results. In newly diagnosed transplant-eligible patients, phase III CASSIOPEIA trial found the combination daratumumab–bortezomib–thalidomide–dexamethasone (Dara-VTd) significantly improves stringent Complete Response (sCR) rate and PFS compared with VTD, whereas in the phase II GRIFFIN study, comparing daratumumab–bortezomib–lenalidomide–dexamethasone (Dara-VRD) vs VRD, sCR rate was significantly higher using quadruplet combination. Many studies are evaluating daratumumab in consolidation and maintenance therapy after autologous stem cell transplantation (ASCT). As regard patients ineligible for ASCT, a great efficacy of daratumumab-containing combinations was reported by the phase III trials ALCYONE and MAIA, exploring daratumumab–bortezomib–melphalan–prednisone (DVMP) vs VMP and daratumumab–lenalidomide–dexamethasone (DRd) vs Rd, respectively. These studies provided results never seen before in this setting. The aim of this paper is to critically review the results obtained with regimens containing daratumumab both in relapsed-refractory and in newly diagnosed MM.
The Hypoxic Microenvironment of Breast Cancer Cells Promotes Resistance in Radiation Therapy
Authors: Gilreath Cordell , Boerma Marjan , Qin Zhiqiang , Hudson M. Keith , Wang Shanzhi
Published: February 2021

The American Cancer Society has estimated an expected 279,100 new breast cancer cases, and an expected 42,690 breast cancer deaths in the U.S. for the year 2020. This includes an estimated 276,480 women who are expected to be diagnosed. Radiation therapy, also called ionizing radiation therapy, is one of the most frequently used methods in the treatment of breast cancer. While radiation therapy is used in the treatment of more than 50% of all cancer cases, tumor resistance to ionizing radiation presents a major challenge for effective cancer treatment. Most tumor cells are in a hypoxic microenvironment that promotes resistance to radiation therapy. In addition to radiation resistance, the hypoxic microenvironment also promotes cancer proliferation and metastasis. In this review, we will discuss the hypoxic microenvironment of breast cancer tumors, related signaling pathways, breast cancer stem-like cells, and the resistance to radiation therapy. Recent developments in our understanding of tumor hypoxia and hypoxic pathways may assist us in developing new strategies to increase cancer control in radiation therapy.
Clinical Benefit of Antiviral Agents for Hepatocellular Carcinoma Patients With Low Preoperative HBV-DNA Loads Undergoing Curative Resection: A Meta-Analysis
Authors: Liu Kai-Xuan , Hong Jian-Guo , Wu Rui , Dong Zhao-Ru , Yang Ya-Fei , Yan Yu-Chuan , Yang Chun-Cheng , Yan Lun-Jie , Yao Sheng-Yu , Li Hai-Chao , Zhi Xu-Ting , Li Tao
Published: February 2021

Background and Aims

The clinical benefit of adjuvant antiviral therapy after curative therapy for HCC in patients with high preoperative HBV-DNA loads has been studied widely but that in patients with low preoperative HBV-DNA loads remains controversial. The purpose of this study was to determine the effect of antiviral treatment prophylaxis on HBV reactivation, overall survival (OS), and postoperative liver function in patients with low preoperative HBV-DNA levels undergoing curative resection.

Methods

A meta-analysis was conducted by searching Web of Science, PubMed, Embase, and Cochrane Library until May 2020. We used REVMAN for data analysis and completed the study under the PRISMA guidelines.

Results

Three randomized trials and seven cohort studies, comprising of 1,131 individuals, were included in the meta-analysis. Antiviral treatment significantly reduced the rate of HBV reactivation after curative treatment of HCC, with a pooled risk ratio of 0.12 (95% c.i. 0.07 to 0.21; P < 0.00001). The trials were consistently favorable for the antiviral group, with a pooled hazard ratio of 0.52 (95% c.i. 0.37 to 0.74; P = 0.0002) in respect of OS rate. However, by pooling the data from studies that reported ALT on the 30th day postoperatively, the result didn’t reach statistical significance (mean difference −4.38, 95% c.i. −13.83 to 5.07; P = 0.36). The I² values of the heterogeneity test for the above three comparisons are zero.

Conclusion

Antiviral therapy during curative resection is effective in reducing HBV reactivation and improving OS rate in HCC patients with low viral load.
Pediatric NMOSD: A Review and Position Statement on Approach to Work-Up and Diagnosis
Authors: Tenembaum Silvia , Yeh E. Ann ,   The Guthy-Jackson Foundation International Clinical Consortium (GJCF-ICC)
Published: February 2021

Neuromyelitis Optica Spectrum Disorder (NMOSD) is an inflammatory demyelinating disease of the central nervous system (CNS) primarily affecting the optic nerves and spinal cord, but also involving other regions of the CNS including the area postrema, periaqueductal gray matter, and hypothalamus. Knowledge related to pediatric manifestations of NMOSD has grown in recent years, particularly in light of newer information regarding the importance of not only antibodies to aquaporin 4 (AQP4-IgG) but also myelin oligodendrocyte glycoprotein (MOG-IgG) in children manifesting clinically with this syndrome. In this review, we describe the current state of the knowledge related to clinical manifestations, diagnosis, and chronic therapies for children with NMOSD, with emphasis on literature that has been published in the last 5 years. Following the review, we propose recommendations for the assessment/follow up clinical care, and treatment of this population.
Linderae Radix Ethanol Extract Alleviates Diet-Induced Hyperlipidemia by Regulating Bile Acid Metabolism Through gut Microbiota
Authors: Jiang Tao , Xu Chuyun , Liu Huifang , Liu Muyi , Wang Minmin , Jiang Jiarui , Zhang Guangji , Yang Chuqi , Huang Jianbo , Lou Zhaohuan
Published: February 2021

Hyperlipidemia is a common metabolic disorder and regarded as one of the main risk factors for cardiovascular disease. The gut microbiota has been identified as a potential contributor to hyperlipidemia as it can greatly regulate bile acid metabolism. Linderae radix is a natural medicine widely used in the treatment of a variety of diseases and is also a common drug for hyperlipidemia. Recently, the lipid-lowering effect of Linderae radix are receiving increasing attention but the underlying mechanism remains unknown. The study aimed to investigate the effects of Linderae radix ethanol extract (LREE) on gut microbiota in rats with hyperlipidemia syndrome. We established a hyperlipidemia rat model using a high-fat diet and used LREE as the intervention. Blood lipid levels and pathological examination were measured to assess the effects of LREE on hyperlipidemia. The gut microbiota was determined by 16s rDNA sequencing and the bile acid metabolism-related proteins were detected by western blot to discover the underlying correlations. The results show that LREE lowered TC, TG, and LDL levels effectively, and it also alleviated liver injury by reducing ALT and AST activity. Meanwhile, LREE improved gut microbiota disturbance caused by HFD via increasing intestinal microbiota diversity and changing the abundance of the Firmicutes, Bacteroidetes, and Actinobacteria. In addition, LREE can increase bile acid reabsorption and promote fecal excretion through farnesoid X receptor (FXR), apical sodium-dependent bile acid transporter (ASBT), organic solute transporter alpha (OST-α), and cytochrome P450 family 7 Subfamily A Member 1 (CYP7A1) thus restoring abnormal bile acid metabolism caused by hyperlipidemia.
Bryophyllum pinnatum Compounds Inhibit Oxytocin-Induced Signaling Pathways in Human Myometrial Cells
Authors: Santos Stefanie , Zurfluh Leonie , Mennet Mónica , Potterat Olivier , von Mandach Ursula , Hamburger Matthias , Simões-Wüst Ana Paula
Published: February 2021

Bryophyllum pinnatum has been used in the treatment of premature labor, first in anthroposophic hospitals and, recently, in conventional settings as an add-on medication. In vitro work with hTERT human myometrial cells showed that B. pinnatum leaf press juice inhibits the increase of intracellular free calcium concentration induced by oxytocin, a hormone known to play a role in labor. Our aim was to identify fractions/compounds in B. pinnatum press juice that contribute to this inhibitory effect, and to investigate their effect on oxytocin-driven activation of the MAPK cascade. Several fractions/compounds from B. pinnatum press juice led to a concentration-dependent decrease of oxytocin-induced increase of intracellular free calcium concentration, but none of them was as strong as B. pinnatum press juice. However, the combination of a bufadienolide and a flavonoid-enriched fraction was as effective as B. pinnatum press juice, and their combination had a synergistic effect. B. pinnatum press juice inhibited oxytocin-driven activation of MAPKs SAPK/JNK and ERK1/2, an effect also exerted by the bufadienolide-enriched fraction. The effect of B. pinnatum press juice on oxytocin-induced signaling pathways was comparable to that of the oxytocin-receptor antagonist and tocolytic agent atosiban. Our findings further substantiate the use of B. pinnatum press juice preparations in the treatment of preterm labor.
CircMAP3K11 Contributes to Proliferation, Apoptosis and Migration of Human Periodontal Ligament Stem Cells in Inflammatory Microenvironment by Regulating TLR4 via miR-511 Sponging
Authors: Yu Bohan , Hu Jiahui , Li Qin , Wang Fang
Published: February 2021

Growing number of studies regarding the role of circRNAs in the development of various diseases have emerged in recent years, but the role of circRNAs in periodontitis pathogenesis remains obscure. Human periodontal ligament stem cells (hPDLSCs) play a critical role in periodontal remodeling, regeneration and repair processes, and their regenerative capacity could be prohibited in local periodontal inflammatory microenvironment. Herein, we sought to uncover the molecular mechanisms of periodontitis pathogenesis by investigating the role of circMAP3K11 (hsa_circ_002284) for regenerative capacity of hPDLSCs under an inflammatory condition. The hPDLSCs isolated from periodontitis patients were used as a cell model of inflammatory microenvironment to study the effect of the circMAP3K11/miR-511-3p/TLR4 axis on the proliferation, apoptosis and migration of hPDLSCs under inflammatory conditions. Compared to the periodontal tissues from normal subjects, those from periodontitis patients exhibited higher expression levels of circMAP3K11 and TLR4, and lower expression level of miR-511-3p. Both the expressions of circMAP3K11 and TLR4 were negatively correlated with the expressions of miR-511-3p in periodontitis. In vitro studies demonstrated that circMAP3K11 is capable of enhancing hPDLSCs proliferation and migration, and reducing the apoptosis of hPDLSCs. We also found that circMAP3K11 could up-regulate the expression of transcription factors that are closely related to periodontal regeneration (Runx2, OSX, ATF4, and BSP). RT-PCR and western blot showed that the inhibitory role of miR-511-3p on TLR4 expression could be reversed by circMAP3K11, which was in line with the results of bioinformatics tools and luciferase reporter assay. Meanwhile, both in vitro and in vivo studies indicated that circMAP3K11 could reverse the effects of miR-511-3p in periodontitis, which further confirmed that circMAP3K11 functioned as a ‘sponge’ of miR-511-3p to positively regulate the expression of TLR4. Taken together, our study preliminarily uncovered a circMAP3K11/miR-511-3p/TLR4 axis that regulates the function of hPDLSCs in periodontitis, providing novel insight and scientific base in the treatment of periodontal tissue regeneration based on stem cells.
Prediction of Paroxysmal Atrial Fibrillation From Complexity Analysis of the Sinus Rhythm ECG: A Retrospective Case/Control Pilot Study
Authors: Alexeenko Vadim , Howlett Philippa J. , Fraser James A. , Abasolo Daniel , Han Thang S. , Fluck David S. , Fry Christopher H. , Jabr Rita I.
Published: February 2021

Paroxysmal atrial fibrillation (PAF) is the most common cardiac arrhythmia, conveying a stroke risk comparable to persistent AF. It poses a significant diagnostic challenge given its intermittency and potential brevity, and absence of symptoms in most patients. This pilot study introduces a novel biomarker for early PAF detection, based upon analysis of sinus rhythm ECG waveform complexity. Sinus rhythm ECG recordings were made from 52 patients with (n = 28) or without (n = 24) a subsequent diagnosis of PAF. Subjects used a handheld ECG monitor to record 28-second periods, twice-daily for at least 3 weeks. Two independent ECG complexity indices were calculated using a Lempel-Ziv algorithm: R-wave interval variability (beat detection, BD) and complexity of the entire ECG waveform (threshold crossing, TC). TC, but not BD, complexity scores were significantly greater in PAF patients, but TC complexity alone did not identify satisfactorily individual PAF cases. However, a composite complexity score (h-score) based on within-patient BD and TC variability scores was devised. The h-score allowed correct identification of PAF patients with 85% sensitivity and 83% specificity. This powerful but simple approach to identify PAF sufferers from analysis of brief periods of sinus-rhythm ECGs using hand-held monitors should enable easy and low-cost screening for PAF with the potential to reduce stroke occurrence.
Effects of Power-Oriented Resistance Training During an Altitude Camp on Strength and Technical Performance of Elite Judokas
Authors: Almeida Filipa , Padial Paulino , Bonitch-Góngora Juan , de la Fuente Blanca , Schoenfeld Brad J. , Morales-Artacho Antonio J. , Benavente Cristina , Feriche Belén
Published: February 2021

This study investigated the effect of a 3-week power-oriented resistance training program performed at moderate altitude on leg power output variables in a countermovement jump, a related judo technique (ippon-seoi-nage) and the relationship between them. Twenty-four elite male judokas were randomly assigned to a hypobaric hypoxia or normoxia group. Mechanical outputs from an incremental loaded countermovement jump test and the kinematic variables transferred to a dummy during an ippon-seoi-nage test (time to execution and movement accelerations) were assessed before, after, 1 and 2 weeks after training. Results indicated an increase in explosive leg capacity both at moderate altitude (2320 m.a.s.l.) and sea level. The hypoxia group showed additional benefits when compared to normoxia group for peak velocities with different percentages of the body weight, maximal theoretical velocity and jump height after the training period, and these additional benefits in jump height were maintained 2 weeks after training. The hypoxia group achieved a higher peak performance in peak velocity and jump height than normoxia group (peak velocity: 8.8 vs. 5.6%, jump height: 8.2 vs. 1.4%, respectively) and was achieved earlier in hypoxia (after training) than in normoxia (1 week after training). However, there was a detrimental effect for the hypoxia group on the times of execution and acceleration of the ippon-seoi-nage compared to the normoxia group. These results suggest that altitude training may induce faster and greater improvements in explosive leg extension capacity. Specific technique-oriented training should be included at altitude to prevent technique impairment.
Quantification of Retinal Vessel Myogenic Constriction in Response to Blood Pressure Peaks: Implications for Flicker Light-Induced Dilatation
Authors: Streese Lukas , Vaes Anja , Infanger Denis , Roth Ralf , Hanssen Henner
Published: February 2021

Background/Aims

Flicker-light induced retinal vessel dilatation (FID), a marker of microvascular endothelial function, has been shown to be blunted in sedentary cardiovascular risk patients (SR) as well as healthy physically active individuals (HA). This study aimed to quantify the retinal myogenic response to blood pressure (BP) peaks and its effects on consecutive FID for differentiation of microvascular health.

Methods

Ten HA and eleven SR with a previously established restriction of arteriolar FID (aFID) (<2.2%) were invited in order to assess BP-induced myogenic constriction following a standardized handgrip task and a consecutive FID. BP was measured beat-to-beat.

Results

The complete dataset of nine HA (3 female, mean age 65 years) and nine SR (5 female, mean age 61 years) individuals was analyzed. The central retinal arteriolar diameter equivalent (CRAE) was 183 ± 11 μm for HA and 176 ± 20 μm for SR. Initial baseline aFID was 1.6 ± 0.4% in HA and 1.6 ± 0.7% in SR. Systolic (p = 0.334) and diastolic (p = 0.245) BP increase following the handgrip task was in the range of 20–30% and comparable in both groups. BP increase was followed by a significantly higher arteriolar (−2.9 ± 1.3% vs. −1.3 ± 0.6%, p < 0.01) myogenic constriction in HA compared to SR. Moreover, in the consecutive assessment of FID directly after the BP-induced vessel constriction, aFID (4.1 ± 2.0% vs. 1.6 ± 0.9%, p < 0.01) was higher in HA compared to SR.

Conclusion

Initial baseline aFID was blunted in HA and SR. Retinal myogenic constriction was impaired in SR compared to HA. The consecutive aFID after BP-induced myogenic constriction recovered in HA but remained blunted in SR. Additional assessment of retinal myogenic constriction needs to be considered to improve CV risk stratification and reduce false-positive findings of endothelial dysfunction in otherwise healthy active individuals.

Clinical Trial Registration

ClinicalTrials.gov: NCT03986892 (https://clinicaltrials.gov/ct2/show/NCT03986892).
Deacetylation of HSC70-4 Promotes Bombyx mori Nucleopolyhedrovirus Proliferation via Proteasome-Mediated Nuclear Import
Authors: Mao Fuxiang , Chen Xi , Ngowo Jonas , Zhu Yajie , Lei Jihai , Gao Xu , Miao Meng , Quan Yanping , Yu Wei
Published: February 2021

Silkworm (Bombyx mori) is a model organism with great agricultural economic value that plays a crucial role in biological studies. B. mori nucleopolyhedrovirus (BmNPV) is a major viral pathogen found in silkworms, which leads to huge silk loss annually. In a recent lysine acetylome of silkworm infected with BmNPV, we focused on the heat shock cognate protein 70-4 (HSC70-4) lysine acetylation change due to the consequent nuclear accumulation and viral structure assembly. In this study, the genome replication, proliferation, and production of budded viruses (BVs) were arrested by HSP/HSC70 inhibitor treatment. However, HSC70-4 overexpression enhanced BmNPV reproduction. Furthermore, site-direct mutagenesis for acetylated mimic (K/Q) or deacetylated mimic (K/R) mutants of HSC70-4 demonstrated that lysine 77 (K77) deacetylation promotes HSC70-4 stability, viral DNA duplication, and HSC70-4 nuclear entry upon BmNPV challenge, and the nuclear propulsion of HSC70-4 after viral stimulus might be dependent on the interaction with the carboxyl terminus of HSC70-interacting protein (CHIP, an E3 ubiquitin ligase), followed by ubiquitin-proteasome system assistance. In this study, single lysine 77 deacetylation of HSC70-4 was deemed a part of the locomotive pathway for facilitating BmNPV proliferation and provided novel insights into the antiviral strategic development.
Body Protein Sparing in Hibernators: A Source for Biomedical Innovation
Authors: Bertile Fabrice , Habold Caroline , Le Maho Yvon , Giroud Sylvain
Published: February 2021

Proteins are not only the major structural components of living cells but also ensure essential physiological functions within the organism. Any change in protein abundance and/or structure is at risk for the proper body functioning and/or survival of organisms. Death following starvation is attributed to a loss of about half of total body proteins, and body protein loss induced by muscle disuse is responsible for major metabolic disorders in immobilized patients, and sedentary or elderly people. Basic knowledge of the molecular and cellular mechanisms that control proteostasis is continuously growing. Yet, finding and developing efficient treatments to limit body/muscle protein loss in humans remain a medical challenge, physical exercise and nutritional programs managing to only partially compensate for it. This is notably a major challenge for the treatment of obesity, where therapies should promote fat loss while preserving body proteins. In this context, hibernating species preserve their lean body mass, including muscles, despite total physical inactivity and low energy consumption during torpor, a state of drastic reduction in metabolic rate associated with a more or less pronounced hypothermia. The present review introduces metabolic, physiological, and behavioral adaptations, e.g., energetics, body temperature, and nutrition, of the torpor or hibernation phenotype from small to large mammals. Hibernating strategies could be linked to allometry aspects, the need for periodic rewarming from torpor, and/or the ability of animals to fast for more or less time, thus determining the capacity of individuals to save proteins. Both fat- and food-storing hibernators rely mostly on their body fat reserves during the torpid state, while minimizing body protein utilization. A number of them may also replenish lost proteins during arousals by consuming food. The review takes stock of the physiological, molecular, and cellular mechanisms that promote body protein and muscle sparing during the inactive state of hibernation. Finally, the review outlines how the detailed understanding of these mechanisms at play in various hibernators is expected to provide innovative solutions to fight human muscle atrophy, to better help the management of obese patients, or to improve the ex vivo preservation of organs.
Control of Cerebral Blood Flow by Blood Gases
Authors: Duffin James , Mikulis David J. , Fisher Joseph A.
Published: February 2021

Cerebrovascular reactivity can be measured as the cerebrovascular flow response to a hypercapnic challenge. The many faceted responses of cerebral blood flow to combinations of blood gas challenges are mediated by its vasculature’s smooth muscle and can be comprehensively described by a simple mathematical model. The model accounts for the blood flow during hypoxia, anemia, hypocapnia, and hypercapnia. The main hypothetical basis of the model is that these various challenges, singly or in combination, act via a common regulatory pathway: the regulation of intracellular hydrogen ion concentration. This regulation is achieved by membrane transport of strongly dissociated ions to control their intracellular concentrations. The model assumes that smooth muscle vasoconstriction and vasodilation and hence cerebral blood flow, are proportional to the intracellular hydrogen ion concentration. Model predictions of the cerebral blood flow responses to hypoxia, anemia, hypocapnia, and hypercapnia match the form of observed responses, providing some confidence that the theories on which the model is based have some merit.
Triploidy in Citrus Genotypes Improves Leaf Gas Exchange and Antioxidant Recovery From Water Deficit
Authors: Lourkisti Radia , Froelicher Yann , Herbette Stéphane , Morillon Raphael , Giannettini Jean , Berti Liliane , Santini Jérémie
Published: February 2021

The triploidy has proved to be a powerful approach breeding programs, especially in Citrus since seedlessness is one of the main consumer expectations. Citrus plants face numerous abiotic stresses including water deficit, which negatively impact growth and crop yield. In this study, we evaluated the physiological and biochemical responses to water deficit and recovery capacity of new triploid hybrids, in comparison with diploid hybrids, their parents (“Fortune” mandarin and “Ellendale” tangor) and one clementine tree used as reference. The water deficit significantly decreased the relative water content (RWC) and leaf gas exchange (Pnet and gs) and it increased the levels of oxidative markers (H2O2 and MDA) and antioxidants. Compared to diploid varieties, triploid hybrids limited water loss by osmotic adjustment as reflected by higher RWC, intrinsic water use efficiency (iWUE Pnet/gs) iWUE and leaf proline levels. These had been associated with an effective thermal dissipation of excess energy (NPQ) and lower oxidative damage. Our results showed that triploidy in citrus enhances the recovery capacity after a water deficit in comparison with diploids due to better carboxylation efficiency, restored water-related parameters and efficient antioxidant system.
Exploring the Molecular Mechanism of Blue Flower Color Formation in Hydrangea macrophylla cv. “Forever Summer”
Authors: Peng Jiqing , Dong Xujie , Xue Chao , Liu Zhiming , Cao Fuxiang
Published: February 2021

Hydrangea macrophylla has a large inflorescence and rich colors, which has made it one of the most popular ornamental flowers worldwide. Thus far, the molecular mechanism of flower color formation in H. macrophylla flowers is unknown. By comparing the pigment content and transcriptome data of the bud period (FSF1), discoloration period (FSF2) and full-bloom stage (FSF3) of infertile blue flowers of H. macrophylla cv. “Forever Summer,” we found that genes associated with anthocyanin production were most associated with the formation of blue infertile flowers throughout development. The anthocyanin biosynthesis pathway is the main metabolic pathway associated with flower color formation, and the carotenoid biosynthesis pathway appeared to have almost no contribution to flower color. There was no competition between the flavonoid and flavonol and anthocyanin biosynthesis pathways for their substrate. At FSF1, the key genes CHS and CHI in the flavonoid biosynthesis pathway were up-regulated, underlying the accumulation of a substrate for anthocyanin synthesis. By FSF3, the downstream genes F3H, C3′5′H, CYP75B1, DFR, and ANS in the anthocyanin biosynthesis pathway were almost all up-regulated, likely promoting the synthesis and accumulation of anthocyanins and inducing the color change of infertile flowers. By analyzing protein–protein interaction networks and co-expression of transcription factors as well as differentially expressed structural genes related to anthocyanin synthesis, we identified negatively regulated transcription factors such as WER-like, MYB114, and WDR68. Their site of action may be the key gene DFR in the anthocyanin biosynthesis pathway. The potential regulatory mechanism of flower color formation may be that WER-like, MYB114, and WDR68 inhibit or promote the synthesis of anthocyanins by negatively regulating the expression of DFR. These results provide an important basis for studying the infertile flower color formation mechanism in H. macrophylla and the development of new cultivars with other colors.
The Arabidopsis thaliana Class II Formin FH13 Modulates Pollen Tube Growth
Authors: Kollárová Eva , Baquero Forero Anežka , Cvrčková Fatima
Published: February 2021

Formins are a large, evolutionarily conserved family of actin-nucleating proteins with additional roles in regulating microfilament, microtubule, and membrane dynamics. Angiosperm formins, expressed in both sporophytic and gametophytic tissues, can be divided into two subfamilies, Class I and Class II, each often exhibiting characteristic domain organization. Gametophytically expressed Class I formins have been documented to mediate plasma membrane-based actin assembly in pollen grains and pollen tubes, contributing to proper pollen germination and pollen tube tip growth, and a rice Class II formin, FH5/RMD, has been proposed to act as a positive regulator of pollen tube growth based on mutant phenotype and overexpression data. Here we report functional characterization of the Arabidopsis thaliana pollen-expressed typical Class II formin FH13 (At5g58160). Consistent with published transcriptome data, live-cell imaging in transgenic plants expressing fluorescent protein-tagged FH13 under the control of the FH13 promoter revealed expression in pollen and pollen tubes with non-homogeneous signal distribution in pollen tube cytoplasm, suggesting that this formin functions in the male gametophyte. Surprisingly, fh13 loss of function mutations do not affect plant fertility but result in stimulation of in vitro pollen tube growth, while tagged FH13 overexpression inhibits pollen tube elongation. Pollen tubes of mutants expressing a fluorescent actin marker exhibited possible minor alterations of actin organization. Our results thus indicate that FH13 controls or limits pollen tube growth, or, more generally, that typical Class II formins should be understood as modulators of pollen tube elongation rather than merely components of the molecular apparatus executing tip growth.
The Effect of Red & Blue Rich LEDs vs Fluorescent Light on Lollo Rosso Lettuce Morphology and Physiology
Authors: Cammarisano Laura , Donnison Iain S. , Robson Paul R. H.
Published: February 2021

The challenges of feeding an increasing population, an increasingly urban population and within an increasingly challenging global environment have focused ideas on new ways to grow food. Growing food in a controlled environment (CE) is not new but new technologies such as broad-spectrum LEDs and robotics are generating new opportunities. Growth recipes can be tailored to plant species in a CE and plasticity in plant responses to the environment may be utilized to make growth systems more efficient for improved yield and crop quality. Light use efficiency within CE must consider energy requirements, yield and impacts on quality. We hypothesized that understanding how plants change their morphology and physiology in response to light will allow us to identify routes to make light more efficient for delivery of high-quality produce. We focused on responses to light in Lollo rosso lettuce which produces compact, crinkly and highly pigmented leaves. We compared the spectra of the commonly used artificial light sources in indoor farming (compact fluorescence tubes, FL, and broad-spectrum light-emitting diodes, LEDs) at two irradiance levels (270 and 570 μmol m–2s–1). We discovered LEDs (λP: 451, 634, and 665 nm) produced the same amount of produce for half the incident energy of FL (T5). At higher irradiances LEDs produced 9% thicker leaves, 13% larger rosettes and 15% greater carotenoid content. Leaves differed in light absorptance with plants grown under lower FL absorbing 30% less of mid-range wavelengths. We show that the relative efficiencies of LED and FL is a function of the irradiances compared and demonstrate the importance of understanding the asymptotes of yield and quality traits. Increasing our understanding of structural and biochemical changes that occur under different combination of wavelengths may allow us to better optimize light delivery, select for different ranges of plasticity in crop plants and further optimize light recipes.
First Case of Glyphosate Resistance in Bromus catharticus Vahl.: Examination of Endowing Resistance Mechanisms
Authors: Yanniccari Marcos , Vázquez-García José G. , Gómez-Lobato María E. , Rojano-Delgado Antonia M. , Alves Pedro L. da C. A. , De Prado Rafael
Published: February 2021

Bromus catharticus Vahl. has been used as a valuable forage crop, but it has also been noted as a weed of winter crops and an invader in several countries. In Argentina, a putative glyphosate-resistant population of B. catharticus was identified as a consequence of the lack of effective control with glyphosate in the pre-sowing of wheat. Plant survival and shikimate accumulation analysis demonstrated a lower glyphosate-sensitivity of this population in comparison to a susceptible B. catharticus population. The resistant population was 4-fold more resistant to glyphosate than its susceptible counterpart. There was no evidence of target-site mechanisms of glyphosate resistance or an enhanced capacity to metabolize glyphosate in the resistant population. However, the resistant plants showed a lower foliar retention of glyphosate (138.34 μl solution g−1 dry weight vs. 390.79 μl solution g−1 dry weight), a reduced absorption of 14C-glyphosate (54.18 vs. 73.56%) and lower translocation of 14C-glyphosate from the labeled leaf (27.70 vs. 62.36%). As a result, susceptible plants accumulated a 4.1-fold higher concentration of 14C-glyphosate in the roots compared to resistant plants. The current work describes the first worldwide case of glyphosate resistance in B. catharticus. A reduced foliar retention of herbicide, a differential rate of glyphosate entry into leaves and an altered glyphosate translocation pattern would be the most likely mechanisms of glyphosate exclusion.
Cracking the “Sugar Code”: A Snapshot of N- and O-Glycosylation Pathways and Functions in Plants Cells
Authors: Strasser Richard , Seifert Georg , Doblin Monika S. , Johnson Kim L. , Ruprecht Colin , Pfrengle Fabian , Bacic Antony , Estevez José M.
Published: February 2021

Glycosylation is a fundamental co-translational and/or post-translational modification process where an attachment of sugars onto either proteins or lipids can alter their biological function, subcellular location and modulate the development and physiology of an organism. Glycosylation is not a template driven process and as such produces a vastly larger array of glycan structures through combinatorial use of enzymes and of repeated common scaffolds and as a consequence it provides a huge expansion of both the proteome and lipidome. While the essential role ofN- andO-glycan modifications on mammalian glycoproteins is already well documented, we are just starting to decode their biological functions in plants. Although significant advances have been made in plant glycobiology in the last decades, there are still key challenges impeding progress in the field and, as such, holistic modern high throughput approaches may help to address these conceptual gaps. In this snapshot, we present an update of the most commonO- andN-glycan structures present on plant glycoproteins as well as (1) the plant glycosyltransferases (GTs) and glycosyl hydrolases (GHs) responsible for their biosynthesis; (2) a summary of microorganism-derived GHs characterized to cleave specific glycosidic linkages; (3) a summary of the available tools ranging from monoclonal antibodies (mAbs), lectins to chemical probes for the detection of specific sugar moieties within these complex macromolecules; (4) selected examples ofN- andO-glycoproteins as well as in their related GTs to illustrate the complexity on their mode of action in plant cell growth and stress responses processes, and finally (5) we present the carbohydrate microarray approach that could revolutionize the way in which unknown plant GTs and GHs are identified and their specificities characterized.
Signal Integration in Plant Abiotic Stress Responses via Multistep Phosphorelay Signaling
Authors: Skalak Jan , Nicolas Katrina Leslie , Vankova Radomira , Hejatko Jan
Published: February 2021

Plants growing in any particular geographical location are exposed to variable and diverse environmental conditions throughout their lifespan. The multifactorial environmental pressure resulted into evolution of plant adaptation and survival strategies requiring ability to integrate multiple signals that combine to yield specific responses. These adaptive responses enable plants to maintain their growth and development while acquiring tolerance to a variety of environmental conditions. An essential signaling cascade that incorporates a wide range of exogenous as well as endogenous stimuli is multistep phosphorelay (MSP). MSP mediates the signaling of essential plant hormones that balance growth, development, and environmental adaptation. Nevertheless, the mechanisms by which specific signals are recognized by a commonly-occurring pathway are not yet clearly understood. Here we summarize our knowledge on the latest model of multistep phosphorelay signaling in plants and the molecular mechanisms underlying the integration of multiple inputs including both hormonal (cytokinins, ethylene and abscisic acid) and environmental (light and temperature) signals into a common pathway. We provide an overview of abiotic stress responses mediated via MSP signaling that are both hormone-dependent and independent. We highlight the mutual interactions of key players such as sensor kinases of various substrate specificities including their downstream targets. These constitute a tightly interconnected signaling network, enabling timely adaptation by the plant to an ever-changing environment. Finally, we propose possible future directions in stress-oriented research on MSP signaling and highlight its potential importance for targeted crop breeding.
Pseudomonas fluorescens DN16 Enhances Cucumber Defense Responses Against the Necrotrophic Pathogen Botrytis cinerea by Regulating Thermospermine Catabolism
Authors: Zhu Lin , Qian Nana , Sun Yujun , Lu Xiaoming , Duan Haiming , Qian Lisheng
Published: February 2021

Plants can naturally interact with beneficial rhizobacteria to mediate defense responses against foliar pathogen infection. However, the mechanisms of rhizobacteria-mediated defense enhancement remain rarely clear. In this study, beneficial rhizobacterial strain Pseudomonas fluorescens DN16 greatly increased the resistance of cucumber plants against Botrytis cinerea infection. RNA-sequencing analyses showed that several polyamine-associated genes including a thermospermine (TSpm) synthase gene (CsACL5) and polyamine catabolic genes (CsPAO1, CsPAO5, and CsCuAO1) were notably induced by DN16. The associations of TSpm metabolic pathways with the DN16-mediated cucumber defense responses were further investigated. The inoculated plants exhibited the increased leaf TSpm levels compared with the controls. Accordantly, overexpression of CsACL5 in cucumber plants markedly increased leaf TSpm levels and enhanced defense against B. cinerea infection. The functions of TSpm catabolism in the DN16-mediated defense responses of cucumber plants to B. cinerea were further investigated by pharmacological approaches. Upon exposure to pathogen infection, the changes of leaf TSpm levels were positively related to the enhanced activities of polyamine catabolic enzymes including polyamine oxidases (PAOs) and copper amine oxidases (CuAOs), which paralleled the transcription of several defense-related genes such as pathogenesis-related protein 1 (CsPR1) and defensin-like protein 1 (CsDLP1). However, the inhibited activities of polyamine catabolic enzymes abolished the DN16-induced cucumber defense against B. cinerea infection. This was in line with the impaired expression of defense-related genes in the inoculated plants challenged by B. cinerea. Collectively, our findings unraveled a pivotal role of TSpm catabolism in the regulation of the rhizobacteria-primed defense states by mediating the immune responses in cucumber plants after B. cinerea infection.
Risk Attitude in the DuLong Minority Ethnicity of China
Authors: Tan Lili , Li Siyuan , Zhang Xiaomin
Published: February 2021

Prospect theory predicts a four-fold risk attitude, which means that people are risk seeking for low-probability gain and high-probability loss and risk averse for low-probability loss and high-probability gain because they overweight probability when it is low. The four-fold pattern of risk attitude has been supported by several former studies with mainstream industrialized populations but has never previously been tested in a non-industrialized society. In this work, we examined the robustness of the four-fold risk attitude in the DuLong minority ethnicity in China, which is a small society with only 4,000 members that is isolated from modern civilization. We used simple lotteries for gain and loss with different probabilities to elicit the risk attitude of 37 DuLong villagers. Our results support prospect theory predictions in that DuLong people are risk seeking for low-probability gain and risk averse for low-probability loss. However, although they showed a tendency to decrease their degree of risk seeking (risk aversion) for gain (loss), their risk attitude did not reverse when the probability of the prospect increased to 50%. In summary, our results suggest a right-shifted weighting function in this non-industrialized small society. The deviation might be caused by the particular living situation of the DuLong people, their sensitivity to monetary payoffs, and the elicitation procedure.
Personality Traits, Loneliness, and Affect Among Boxers
Authors: Chen Xin , Qiu Nan , Chen Chao , Zhai Liang
Published: February 2021

This study aimed to test the association between personality traits and affect among boxers and to figure out whether loneliness mediated this relationship. This study used The Big Five Personality Traits Scale, The UCLA Loneliness Scale, and The Positive and Negative Affect Scale (PANAS) which were administered to N = 231 boxers (age: M = 20.28; SD = 2.60), of which 62% were male (n = 144) and 38% were female (n = 87). The results showed that (1) conscientiousness, extraversion, and agreeableness were negatively related with negative affect, neuroticism was positively associated with negative affect, and openness showed no relationship with negative affect; (2) conscientiousness, extraversion, and agreeableness were all positively correlated with positive affect, neuroticism was negatively associated with positive affect, and openness showed no relationship with positive affect; (3) conscientiousness, extraversion, openness, and agreeableness were negatively related with loneliness and neuroticism was positively associated with loneliness; and (4) loneliness was positively associated with negative affect; loneliness was negatively associated with positive affect; and loneliness had mediating effect on the relationship between the personality traits and affect. Furthermore, these findings suggest that loneliness might be one mechanism explaining how boxer’s personality traits influence their athletic performance. Therefore, in the future, we should start by helping them reduce their loneliness to reduce their negative affect and improve their positive affect and also, in some degree, to enhance boxers’ athletic ability and mental quality health.
Respiratory Sinus Arrhythmia Mediates the Relation Between “Specific Math Anxiety” and Arithmetic Speed
Authors: Tang Jiuqing , Su Yun , Yao Yu'e , Peyre Hugo , Guez Ava , Zhao Jingjing
Published: February 2021

There is a growing consensus that math anxiety highly correlates with trait anxiety and that the emotional component elicited by math anxiety affects math performance. Yet few studies have examined the impact of “specific math anxiety” (high math anxiety and low other kinds of anxiety) on math performance and the underlying physiological and affective mechanism. The present study examines the mediation effect of heart rate variability—an affective measurement indexed by respiratory sinus arrhythmia (RSA)—in the relationship between specific math anxiety and arithmetic speed. A total of 386 junior high school students completed a self-reported questionnaire to measure their anxiety level. Among this sample, 29 individuals with specific math anxiety (high math anxiety and low reading and trait anxiety), 29 with specific reading anxiety (high reading anxiety and low math and trait anxiety), 24 with specific trait anxiety (high trait anxiety and low math and reading anxiety), and 22 controls (low math, trait and reading anxiety) were selected to participate in an arithmetic task and a reading task while RSA was recorded when they performed the tasks. Results revealed that individuals with specific math anxiety showed lower RSA and longer reaction time than the other three groups in the arithmetic task. Regression and mediation analyses further revealed that RSA mediated the relation between specific math anxiety and arithmetic speed. The present study provides the first account of evidence for the affective hypothesis of specific math anxiety and suggests that affective responses may be an important mechanism underlying the detrimental effect of specific math anxiety on math performance.