Challenges of mesenchymal stem cells in the clinical treatment of COVID-19.

The 2019 coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has brought an enormous public health burden to the global society. The duration of the epidemic, the number of infected people, and the widespread of the epidemic are extremely rare in modern society. In the initial stage of infection, people generally show fever, cough, and dyspnea, which can lead to pneumonia, acute respiratory syndrome, kidney failure, and even death in severe cases. The strong infectivity and pathogenicity of SARS-CoV-2 make it more urgent to find an effective treatment. Mesenchymal stem cells (MSCs) are a kind of pluripotent stem cells with the potential for self-renewal and multi-directional differentiation. They are widely used in clinical experiments because of their low immunogenicity and immunomodulatory function. Mesenchymal stem cell-derived exosomes (MSC-Exo) can play a physiological role similar to that of stem cells. Since the COVID-19 pandemic, a series of clinical trials based on MSC therapy have been carried out. The results show that MSCs are safe and can significantly improve patients' respiratory function and prognosis of COVID-19. Here, the effects of MSCs and MSC-Exo in the treatment of COVID-19 are reviewed, and the clinical challenges that may be faced in the future are clarified.

TEP SNORD12B, SNORA63, and SNORD14E as novel biomarkers for hepatitis B virus-related hepatocellular carcinoma (HBV-related HCC).

PURPOSE: The alterations of RNA profile in tumor-educated platelets (TEPs) have been described as a novel biosource for cancer diagnostics. This study aimed to explore the potential snoRNAs in TEP as biomarkers for diagnostics of hepatitis B virus-related hepatocellular carcinoma (HBV-related HCC). METHODS: Platelets were isolated using low-speed centrifugation and subjected to a quantitative polymerase chain reaction (qPCR) for snoRNAs detection. RESULTS: Down-regulated SNORD12B and SNORD14E as well as up-regulated SNORA63 were identified in TEP from HBV-related HCC, which could act as diagnostic biomarkers for HBV-related HCC as well as the early disease. Besides, TEP SNORD12B, SNORD14E, and SNORA63 facilitate the diagnostic performance of AFP and achieve favorable diagnostics efficiency for HBV-related HCC when combined with platelet parameters. CONCLUSIONS: Aberrant expression of SNORD12B, SNORA63, and SNORD14E in TEPs could serve as the novel and non-invasive biomarkers for HBV-related HCC diagnosis.

Neuroprotective effects of mesenchymal stromal cells in mouse models of Alzheimer's Disease: The Mediating role of gut microbes and their metabolites via the Microbiome-Gut-Brain axis.

The intricacy and multifaceted nature of Alzheimer's disease (AD) necessitate therapies that target multiple aspects of the disease. Mesenchymal stromal cells (MSCs) emerge as potential agents to mitigate AD symptoms; however, whether their therapeutic efficacy involves modulation of gut microbiota and the microbiome-gut-brain axis (MGBA) remains unexplored. In this study, we evaluated the effects of three distinct MSCs types-derived from the umbilical cord (UCMSC), dental pulp (SHED), and adipose tissue (ADSC)-in an APP/PS1 mouse model of AD. In comparison to saline control, MSCs administration resulted in a significant reduction of behavioral disturbances, amyloid plaques, and phosphorylated tau in the hippocampus and frontal cortex, accompanied by an increase in neuronal count and Nissl body density across AD-afflicted brain regions. Through 16S rRNA gene sequencing, we identified partial restoration of gut microbial balance in AD mice post-MSCs treatment, evidenced by the elevation of neuroprotective Akkermansia and reduction of the AD-associated Sphingomonas. To examine whether gut microbiota involved in MSCs efficacy in treating AD, SHED with better anti-inflammatory and gut microbiota recovery effects among three MSCs, and another AD model 5 × FAD mice with earlier and more pathological proteins in brain than APP/PS1, were selected for further studies. Antibiotic-mediated gut microbial inactivation attenuated MSCs efficacy in 5 × FAD mice, implicating the involvement of gut microbiota in the therapeutic mechanism. Functional analysis of altered gut microbiota and targeted bile acid metabolism profiling revealed a significant enhancement in bile acid variety following MSCs therapy. A chief bile acid constituent, taurocholic acid (TCA), was orally administered to AD mice and similarly abated AD symptoms. Nonetheless, the disruption of intestinal neuronal integrity with enterotoxin abrogated the ameliorative impact of both MSCs and TCA treatments. Collectively, our findings substantiate that MSCs confer therapeutic benefits in AD within a paradigm that primarily involves regulation of gut microbiota and their metabolites through the MGBA.

Study of symptom clusters in brain tumor patients 2 weeks after craniotomy.

BACKGROUND: This study aimed to identify potential symptom clusters among primary brain tumor patients using factor analysis. Understanding these clusters enables better-targeted interventions post-craniotomy. METHODS: A total of 211 participants visiting Department of Neurosurgery at Shanghai Tenth People's Hospital for proposed surgical treatment between January 2021 and March 2022 were enrolled. Two weeks after craniotomy, the patients' symptoms were measured using MDASI-BT (M.D. Anderson Symptom Inventory Brain Tumor Module), and factor analysis was performed to identify symptom clusters. RESULTS: A total of three symptom clusters, i.e., symptom cluster 1, symptom cluster 2, and symptom cluster 3, were identified. Among them, symptom cluster 1 represented the fatigue-related symptom cluster, including fatigue, lethargy, dry mouth, pain, and sleep disturbance (Cronbach's α = 0.742); symptom cluster 2 represented the gut-brain axis symptom cluster, including loss of appetite, weakness in one side of the body, and change in bowel habits (Cronbach's α = 0.532); and symptom cluster 3 represented the self-image symptom cluster, including change in appearance, sadness, and distress (Cronbach's α = 0.547). CONCLUSION: This study identified three potential symptom clusters among primary brain tumor patients. Understanding these clusters could well contribute to earlier interventions and improved quality of care.

Optimizing post-craniotomy recovery: insights from symptom network analysis in primary brain tumor patients.

BACKGROUND: Craniotomy to remove brain tumors is an intricate procedure with multiple postoperative symptoms. However, there has been limited research on the symptom networks of these patients. To this end, this study aims to explore these symptom networks, revealing their interplay to inform better symptom control, hasten the discovery of postoperative issues, and tailor Enhanced Recovery After Surgery (ERAS) protocols, all to enhance recovery and enhance patient care. METHODS: From September 2023 to March 2024, 211 patients with primary brain tumors who underwent craniotomy at Shanghai Tongji Hospital were recruited. Their symptoms were assessed using the MDASI-BT (M.D. Anderson Symptom Inventory Brain Tumor Module) one day post-craniotomy. The symptom network of 22 symptoms was visualized using R, with central and bridge symptoms identified. RESULTS: Sadness (rs=2.482) and difficulty in understanding (rs=1.138) have the highest strength of all symptoms, indicating they are the central symptoms. Sadness (rb=2.155) and loss of appetite (rb=1.828) have the highest value of betweenness, indicating they are the bridge symptoms. Strong correlations were found between difficulty in understanding and difficulty in speaking (r = 0.701), distress and sadness (r = 0.666), fatigue and lethargy (r = 0.632), and nausea and vomiting (r = 0.601). Subgroup analysis revealed that noninvasive tumor patients exhibited similar symptom networks to the overall cohort, whereas invasive tumor patients showed weak symptom connections, resulting in no discernible network. CONCLUSION: This study underscores the importance of understanding symptom networks in brain tumor patients post-craniotomy, highlighting key symptom interrelationships. These insights can guide more effective symptom management, early complication detection, and optimization of ERAS protocols, ultimately enhancing recovery and patient care.

Effectiveness of exercise-based cardiac rehabilitation for patients with left ventricular assist device: A systematic review and meta-analysis.

PURPOSE: Exercise-based cardiac rehabilitation (EBCR) improves functional capacity in heart failure (HF). However, data on the effect of EBCR in patients with advanced HF and left ventricular assist devices (LVADs) are limited. This meta-analysis aimed to evaluate the impact of EBCR on the functional ability of LVAD patients by comparing the corresponding outcome indicators between the EBCR and ST groups. METHODS: PubMed, Embase, Clinical Trials, and Cochrane Library databases were searched for studies assessing and comparing the effects of EBCR and standard therapy (ST) in patients following LVAD implantation. Using pre-defined criteria, appropriate studies were identified and selected. Data from selected studies were extracted in a standardized fashion, and a meta-analysis was performed using a fixed-effects model. The protocol was registered on INPLASY (202340073). RESULTS: In total, 12 trials involving 477 patients were identified. The mean age of the participants was 52.9 years, and 78.6% were male. The initiation of EBCR varied from LVAD implantation during the index hospitalization to 11 months post-LVAD implantation. The median rehabilitation period ranged from 2 weeks to 18 months. EBCR was associated with improved peak oxygen uptake (VO2) in all trials. Quantitative analysis was performed in six randomized studies involving 214 patients (EBCR: n = 130, ST: n = 84). EBCR was associated with a significantly high peak VO2 (weighted mean difference [WMD] = 1.64 mL/kg/min; 95% confidence interval [CI], 0.20-3.08; p = .03). Similarly, 6-min walk distance (6MWD) showed significantly greater improvement in the EBCR group than in the ST group (WMD = 34.54 m; 95% CI, 12.47-56.42; p = .002) in 266 patients (EBCR, n = 140; ST, n = 126). Heterogeneity was low among the included trials. None of the included studies reported serious adverse events related to EBCR, indicating the safety of EBCR after LVAD implantation. CONCLUSION: This study demonstrated that EBCR following LVAD implantation is associated with greater improvement in functional capacity compared with ST as reflected by the improved peak VO2 and 6MWD values. Considering the small number of patients in this analysis, further research on the clinical impact of EBCR in LVAD patients is warranted.

Establishment of cerebral perfusion in a rat model with extracorporeal life support.

Background: Extracorporeal life support echniques as an Adjunct to Advanced Cardiac Life Support is usually suitable for complex heart surgery such as cardiopulmonary bypass (CPB). Cerebral perfusion is a clinically feasible neuroprotective strategy; however, the lack of a reliable small animal model.Methods: Based on the rat model of ECLS we evaluate the effects of ECLS-CP using HE staining, Nissl staining, TUNEL staining and ELISA.Result: We found that ECLS combined with the cerebral perfusion model did not cause brain injury and immune inflammation. There was no difference between the two by a left carotid artery or right carotid artery CP.Conclusion: These experimental results can provide the experimental basis for selecting blood vessels for ECLS patients and clinical CP to offers a trustworthy animal model for future exploration of applying brain perfusion strategies during ECLS-CP.

Recent Progress in Modifications, Properties, and Practical Applications of Glass Fiber.

As a new member of the silica-derivative family, modified glass fiber (MGF) has attracted extensive attention because of its excellent properties and potential applications. Surface modification of glass fiber (GF) greatly changes its performance, resulting in a series of changes to its surface structure, wettability, electrical properties, mechanical properties, and stability. This article summarizes the latest research progress in MGF, including the different modification methods, the various properties, and their advanced applications in different fields. Finally, the challenges and possible solutions were provided for future investigations of MGF.

Intestinal Flora Affect Alzheimer's Disease by Regulating Endogenous Hormones.

Alzheimer's disease (AD) is a central nervous system disease that can lead to cognitive impairment and progressive memory loss. An increasing number of studies have shown that intestinal flora play a crucial role in regulating the brain-gut axis. Short-chain fatty acids are metabolites of intestinal flora that regulate hormone synthesis and play an essential role in microbial-intestinal-brain communication. An imbalance of intestinal flora can promote microglia to secrete proinflammatory factors, cause nerve inflammation, and then affect cognitive and learning ability. However, the mechanism is not clear. From this, we infer that endogenous hormones may be the medium for intestinal flora to affect the process of AD. This review of the relationships among AD, endogenous hormones, and intestinal flora expounds on the critical role of various hormones in the brain-gut axis. It discusses intervention measures aimed at intestinal flora to prevent or delay AD occurrence. Finally, the potential development prospects of fecal microbiota transplantation in treating AD are put forward, which provide potential ideas for future AD research.

Preparation of bimetal-polydopamine organic frameworks with core-shell structure and their application in HER2 detection.

Human epidermal growth factor receptor 2 (HER2) is one of the specific markers of breast cancer, which is of great significance to the early diagnosis and prognosis of breast cancer. Here, a fluorescence biosensor was established to detect HER2 based on the fluorescence resonance energy transfer (FRET) and photoinduced electron transfer (PET) occurring between the bimetal-polydopamine organic framework with core-shell structure Au@PDA@UiO-66 and the Cy5 fluorophore in HER2-Cy5-Apt. Au@PDA@UiO-66 owns high-efficiency fluorescence quenching ability due to its large specific surface area and strong adsorption of single-stranded DNA. When the target appears, the fluorescence recovery space mediated by the target is large, so the proposed biosensor has better sensitivity in theory. Under optimized conditions, the proposed fluorescent biosensor can detect HER2 in a range of 0.005 ng mL-1 to 15 ng mL-1, with an actual detection limit as low as 0.005 ng mL-1. Corresponding selective experiments, reproducible experiments, and spiked experiments performed well, showing its great potential in HER2 detection.

Prediction of the Nitrogen Content of Rice Leaf Using Multi-Spectral Images Based on Hybrid Radial Basis Function Neural Network and Partial Least-Squares Regression.

This paper's novel focus is predicting the leaf nitrogen content of rice during growing and maturing. A multispectral image processing-based prediction model of the Radial Basis Function Neural Network (RBFNN) model was proposed. Moreover, this paper depicted three primary points as the following: First, collect images of rice leaves (RL) from a controlled condition experimental laboratory and new shoot leaves in different stages in the visible light spectrum, and apply digital image processing technology to extract the color characteristics of RL and the morphological characteristics of the new shoot leaves. Secondly, the RBFNN model, the General Regression Model (GRL), and the General Regression Method (GRM) model were constructed based on the extracted image feature parameters and the nitrogen content of rice leaves. Third, the RBFNN is optimized by and Partial Least-Squares Regression (RBFNN-PLSR) model. Finally, the validation results show that the nitrogen content prediction models at growing and mature stages that the mean absolute error (MAE), the Mean Absolute Percentage Error (MAPE), and the Root Mean Square Error (RMSE) of the RFBNN model during the rice-growing stage and the mature stage are 0.6418 (%), 0.5399 (%), 0.0652 (%), and 0.3540 (%), 0.1566 (%), 0.0214 (%) respectively, the predicted value of the model fits well with the actual value. Finally, the model may be used to give the best foundation for achieving exact fertilization control by continuously monitoring the nitrogen nutrition status of rice. In addition, at the growing stage, the RBFNN model shows better results compared to both GRL and GRM, in which MAE is reduced by 0.2233% and 0.2785%, respectively.

Pathogenic Hydrogel? A Novel-Entrapment Neuropathy Model Induced by Ultrasound-Guided Perineural Injections.

Entrapment neuropathy (EN) is a prevalent and debilitative condition caused by a complex pathogenesis that involves a chronic compression-edema-ischemia cascade and perineural adhesion that results in excessive shear stress during motion. Despite decades of research, an easily accessible and surgery-free animal model mimicking the mixed etiology is currently lacking, thus limiting our understanding of the disease and the development of effective therapies. In this proof-of-concept study, we used ultrasound-guided perineural injection of a methoxy poly(ethylene glycol)-b-Poly(lactide-co-glycoilide) carboxylic acid (mPEG-PLGA-BOX) hydrogel near the rat's sciatic nerve to induce EN, as confirmed sonographically, electrophysiologically, and histologically. The nerve that was injected with hydrogel appeared unevenly contoured and swollen proximally with slowed nerve conduction velocities across the injected segments, thus showing the compressive features of EN. Histology showed perineural cellular infiltration, deposition of irregular collagen fibers, and a possible early demyelination process, thus indicating the existence of adhesions. The novel method provides a surgery-free and cost-effective way to establish a small-animal model of EN that has mixed compression and adhesion features, thus facilitating the additional elucidation of the pathophysiology of EN and the search for promising treatments.

Colorimetric and fluorescent dual-identification of glutathione based on its inhibition on the 3D ball-flower shaped Cu-hemin-MOF's peroxidase-like activity.

Hemin as the organic linker ligand and Cu (II) as the metal center were applied to prepare a copper-metal-organic framework (Cu-hemin-MOF) via one-step hydrothermal method. Characterization using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), and X-ray powder diffraction (XRD) demonstrate that the acquired Cu-hemin-MOF possesses the appearance of 3D ball-flower shape with the existence of C, N, O, Fe, and Cu on the surface. Further study found that this 3D ball-flower shaped Cu-hemin-MOF exhibits peroxidase-like activity, which can catalyze the peroxidase substrate of o-phenylenediamine (OPD) to generate 2,3-diaminophenazine (DAP) in the presence of H2O2. DAP has a yellow color and also emits a strong fluorescence when excited by ultraviolet light. Interestingly, Cu-hemin-MOF's peroxidase-like activity can be strongly inhibited by glutathione (GSH). In view of this, a dual readout (fluorescence and colorimetry) was proposed to detect GSH for the first time. Under optimal conditions, the proposed method exhibits good linear relationship between the signal response (fluorescence and colorimetry) and the concentration of GSH, and low limits of detection (LOD) of 2.3 and 26.6 nM, respectively.Graphical abstract.

GBSS-BINDING PROTEIN, encoding a CBM48 domain-containing protein, affects rice quality and yield.

The percentage of amylose in the endosperm of rice (Oryza sativa) largely determines grain cooking and eating qualities. Granule-bound starch synthase I (GBSSI) and GBSSII are responsible for amylose biosynthesis in the endosperm and leaf, respectively. Here, we identified OsGBP, a rice GBSS-binding protein that interacted with GBSSI and GBSSII in vitro and in vivo. The total starch and amylose contents in osgbp mutants were significantly lower than those of wild type in leaves and grains, resulting in reduced grain weight and quality. The carbohydrate-binding module 48 (CBM48) domain present in the C-terminus of OsGBP is crucial for OsGBP binding to starch. In the osgbp mutant, the extent of GBSSI and GBSSII binding to starch in the leaf and endosperm was significantly lower than wild type. Our data suggest that OsGBP plays an important role in leaf and endosperm starch biosynthesis by mediating the binding of GBSS proteins to developing starch granules. This elucidation of the function of OsGBP enhances our understanding of the molecular basis of starch biosynthesis in rice and contributes information that can be potentially used for the genetic improvement of yield and grain quality.

Generation of a new thermo-sensitive genic male sterile rice line by targeted mutagenesis of TMS5 gene through CRISPR/Cas9 system.

BACKGROUND: Two-line hybrid rice with high yield potential is increasingly popular and the photo- and temperature-sensitive male sterile line is one of the basic components for two-line hybrid rice breeding. The development of male sterile lines through conventional breeding is a lengthy and laborious process, whereas developing thermo-sensitive genic male sterile (TGMS) lines for two-line hybrid breeding by editing a temperature-sensitivity gene by CRISPR/Cas9 is efficient and convenient. RESULTS: Here, thermo-sensitive genic male sterility (TGMS) was induced by employing the CRISPR/Cas9 gene editing technology to modify the gene TMS5. Two TGMS mutants, tms5-1 and tms5-2, both lacking any residual T-DNA, were generated in the indica rice cultivar Zhongjiazao17 (cv. YK17) background. When grown at a sub-optimal temperature (22 °C), both mutants produced viable pollen and successfully produced grain through self-fertilization, but at temperatures 24 and 26 °C, their pollen was sterile and no grain was set. F1 hybrids derived from the crosses between YK17S (tms5-1) and three different restorer lines outperformed both parental lines with respect to grain yield and related traits. CONCLUSION: The YK17S generated by CRISPR/Cas9 system was proved to be a new TGMS line with superior yield potential and can be widely utilized in two-line hybrid breeding of indica rice.

NF-YB1-YC12-bHLH144 complex directly activates Wx to regulate grain quality in rice (Oryza sativa L.).

Identification of seed development regulatory genes is the key for the genetic improvement in rice grain quality. NF-Ys are the important transcription factors, but their roles in rice grain quality control and the underlying molecular mechanism remain largely unknown. Here, we report the functional characterization a rice NF-Y heterotrimer complex NF-YB1-YC12-bHLH144, which is formed by the binding of NF-YB1 to NF-YC12 and then bHLH144 in a sequential order. Knock-out of each of the complex genes resulted in alteration of grain qualities in all the mutants as well as reduced grain size in crnf-yb1 and crnf-yc12. RNA-seq analysis identified 1496 genes that were commonly regulated by NF-YB1 and NF-YC12, including the key granule-bound starch synthase gene Wx. NF-YC12 and bHLH144 maintain NF-YB1 stability from the degradation mediated by ubiquitin/26S proteasome, while NF-YB1 directly binds to the 'G-box' domain of Wx promoter and activates Wx transcription, hence to regulate rice grain quality. Finally, we revealed a novel grain quality regulatory pathway controlled by NF-YB1-YC12-bHLH144 complex, which has great potential for rice genetic improvement.

The Effect of the Repression of Oxidative Stress on Tenocyte Differentiation: A Preliminary Study of a Rat Cell Model Using a Novel Differential Tensile Strain Bioreactor.

Because of limitations in the current understanding of the exact pathogenesis of tendinopathy, and the lack of an optimal experimental model, effective therapy for the disease is currently unavailable. This study aims to prove that repression of oxidative stress modulates the differentiation of tendon-derived cells (TDCs) sustaining excessive tensile strains, and proposes a novel bioreactor capable of applying differential tensile strains to cultured cells simultaneously. TDCs, including tendon-derived stem cells, tenoblasts, tenocytes, and fibroblasts, were isolated from the patellar tendons of Sprague‒Dawley rats. Cyclic uniaxial stretching with 4% or 8% strain at 0.5 Hz for 8 h was applied to TDCs. TDCs subjected to 8% strain were treated with epigallocatechin gallate (EGCG), piracetam, or no medication. Genes representing non-tenocyte lineage (Pparg, Sox9, and Runx2) and type I and type III collagen were analyzed by quantitative polymerase chain reaction. The 8% strain group showed increased expression of non-tenocyte lineage genes and type III/type I collagen ratios compared with the control and 4% strain groups, and the increased expression was ameliorated with addition of EGCG and piracetam. The model developed in this work could be applied to future research on the pathophysiology of tendinopathy and development of treatment options for the disease. Repression of oxidative stress diminishes the expression of genes indicating aberrant differentiation in a rat cell model, which indicates potential therapeutic intervention of tendinopathy, the often relentlessly degenerate condition.

OsPK2 encodes a plastidic pyruvate kinase involved in rice endosperm starch synthesis, compound granule formation and grain filling.

Starch is the main form of energy storage in higher plants. Although several enzymes and regulators of starch biosynthesis have been defined, the complete molecular machinery remains largely unknown. Screening for irregularities in endosperm formation in rice represents valuable prospect for studying starch synthesis pathway. Here, we identified a novel rice white-core endosperm and defective grain filling mutant, ospk2, which displays significantly lower grain weight, decreased starch content and alteration of starch physicochemical properties when compared to wild-type grains. The normal starch compound granules were drastically reduced and more single granules filled the endosperm cells of ospk2. Meanwhile, the germination rate of ospk2 seeds after 1-year storage was observably reduced compared with wild-type. Map-based cloning of OsPK2 indicated that it encodes a pyruvate kinase (PK, ATP: pyruvate 2-O-phosphotransferase, EC 2.7.1.40), which catalyses an irreversible step of glycolysis. OsPK2 has a constitutive expression in rice and its protein localizes in chloroplasts. Enzyme assay showed that the protein product from expressed OsPK2 and the crude protein extracted from tissues of wild-type exhibits strong PK activity; however, the mutant presented reduced protein activity. OsPK2 (PKpα1) and three other putative rice plastidic isozymes, PKpα2, PKpß1 and PKpß2, can interact to form heteromer. Moreover, the mutation leads to multiple metabolic disorders. Altogether, these results denote new insights into the role of OsPK2 in plant seed development, especially in starch synthesis, compound granules formation and grain filling, which would be useful for genetic improvement of high yield and rice grain quality.

Single-shot T2 mapping using overlapping-echo detachment planar imaging and a deep convolutional neural network.

PURPOSE: An end-to-end deep convolutional neural network (CNN) based on deep residual network (ResNet) was proposed to efficiently reconstruct reliable T2 mapping from single-shot overlapping-echo detachment (OLED) planar imaging. METHODS: The training dataset was obtained from simulations that were carried out on SPROM (Simulation with PRoduct Operator Matrix) software developed by our group. The relationship between the original OLED image containing two echo signals and the corresponding T2 mapping was learned by ResNet training. After the ResNet was trained, it was applied to reconstruct the T2 mapping from simulation and in vivo human brain data. RESULTS: Although the ResNet was trained entirely on simulated data, the trained network was generalized well to real human brain data. The results from simulation and in vivo human brain experiments show that the proposed method significantly outperforms the echo-detachment-based method. Reliable T2 mapping with higher accuracy is achieved within 30 ms after the network has been trained, while the echo-detachment-based OLED reconstruction method took approximately 2 min. CONCLUSION: The proposed method will facilitate real-time dynamic and quantitative MR imaging via OLED sequence, and deep convolutional neural network has the potential to reconstruct maps from complex MRI sequences efficiently.

White Leaf and Panicle 2, encoding a PEP-associated protein, is required for chloroplast biogenesis under heat stress in rice.

The plastid-encoded RNA polymerase (PEP) plays an important role in the transcription machinery of mature chloroplasts, yet details of its function remain elusive in rice. Here, we identified a novel PEP-associated protein (PAP), WLP2, based on its two allelic white leaf and panicle mutants, wlp2s and wlp2w. The two mutants were albino lethal at high temperatures and showed decreased chlorophyll accumulation, abnormal chloroplast ultrastructure, and attenuated photosynthetic activity. Map-based cloning suggested that WLP2 encodes a putative pfkB-type carbohydrate kinase family protein, which is homologous to fructokinase-like 1 (AtFLN1) in Arabidopsis. WLP2 is mainly expressed in green tissues and its protein localizes in chloroplasts. Expression levels of PEP-encoded genes, chloroplast development genes and photosynthesis-related genes were compromised in wlp2 mutants, indicating that WLP2 is essential for normal chloroplast biogenesis. Moreover, WLP2 and its paralog OsFLN2 can physically interact with thioredoxin OsTRXz to form a TRX-FLN regulatory module, which not only regulates transcription of the PEP-encoded genes but also maintains the redox balance in chloroplasts under heat stress. Furthermore, the wlp2w mutant gene represents a potential advantage in enhancing seed purity and high-throughput breeding. Our results strongly indicate that WLP2 protects chloroplast development from heat stress via a TRX-FLN regulatory module in rice.