Gibberellins involved in fruit ripening and softening by mediating multiple hormonal signals in tomato.

The phytohormone ethylene is well known for its important role in the ripening of climacteric fruit, such as tomato (Solanum lycopersicum). However, the role and mode of action of other plant hormones in climacteric fruit ripening regulation are not fully understood. Here, we showed that exogenous GA treatment or increasing endogenous gibberellin content by overexpressing the gibberellin synthesis gene SlGA3ox2 specifically in fruit tissues delayed tomato fruit ripening, whereas treatment with the GA biosynthesis inhibitor paclobutrazol (PAC) accelerated fruit ripening. Moreover, exogenous ethylene treatment cannot completely reverse the delayed fruit ripening phenotype. Furthermore, exogenous GA treatment of ethylene signalling mutant Never ripe (Nr) or SlEBF3-overexpressing lines still delayed fruit ripening, suggesting that GA involved in fruit ripening partially depends on ethylene. Transcriptome profiling showed that gibberellin affect the ripening of fruits by modulating the metabolism and signal transduction of multiple plant hormones, such as auxin and abscisic acid, in addition to ethylene. Overall, the results of this study provide new insight into the regulation of gibberellin in fruit ripening through mediating multiple hormone signals.

Boosting microscopic object detection via feature activation map guided poisson blending.

Microscopic examination of visible components based on micrographs is the gold standard for testing in biomedical research and clinical diagnosis. The application of object detection technology in bioimages not only improves the efficiency of the analyst but also provides decision support to ensure the objectivity and consistency of diagnosis. However, the lack of large annotated datasets is a significant impediment in rapidly deploying object detection models for microscopic formed elements detection. Standard augmentation methods used in object detection are not appropriate because they are prone to destroy the original micro-morphological information to produce counterintuitive micrographs, which is not conducive to build the trust of analysts in the intelligent system. Here, we propose a feature activation map-guided boosting mechanism dedicated to microscopic object detection to improve data efficiency. Our results show that the boosting mechanism provides solid gains in the object detection model deployed for microscopic formed elements detection. After image augmentation, the mean Average Precision (mAP) of baseline and strong baseline of the Chinese herbal medicine micrograph dataset are increased by 16.3% and 5.8% respectively. Similarly, on the urine sediment dataset, the boosting mechanism resulted in an improvement of 8.0% and 2.6% in mAP of the baseline and strong baseline maps respectively. Moreover, the method shows strong generalizability and can be easily integrated into any main-stream object detection model. The performance enhancement is interpretable, making it more suitable for microscopic biomedical applications.

Augmented Super-Resolution Radial Fluctuations (aSRRF) Pushing the Limits of Structured Illumination Microscopy.

Structured illumination microscopy (SIM) is a versatile super-resolution technique known for its compatibility with a wide range of probes and fast implementation. While 3D SIM is capable of achieving a spatial resolution of ∼120 nm laterally and ∼300 nm axially, attempting to further enhance the resolution through methods such as nonlinear SIM or 4-beam SIM introduces complexities in optical configurations, increased phototoxicity, and reduced temporal resolution. Here, we have developed a novel method that combines SIM with augmented super-resolution radial fluctuations (aSRRF) utilizing a single image through image augmentation. By applying aSRRF reconstruction to SIM images, we can enhance the SIM resolution to ∼50 nm isotopically, without requiring any modifications to the optical system or sample acquisition process. Additionaly, we have incorporated the aSRRF approach into an ImageJ plugin and demonstrated its versatility across various fluorescence microscopy images, showcasing a remarkable two-fold resolution increase.

ChsA, a Class â ¡ Chitin Synthase, Contributes to Asexual Conidiation, Mycelial Morphology, Cell Wall Integrity, and the Production of Enzymes and Organic Acids in Aspergillus niger.

Chitin synthases (CHSs) are vital enzymes for the synthesis of chitin and play important and differential roles in fungal development, cell wall integrity, environmental adaptation, virulence, and metabolism in fungi. However, except for ChsC, a class III CHS, little is known about the functions of CHSs in Aspergillus niger, an important fungus that is widely applied in the fermentation industry and food processing, as well as a spoilage fungus of food and a human pathogen. This study showed the important functions of ChsA, a class II CHS, in A. niger using multi-phenotypic and transcriptional analyses under various conditions. The deletion of chsA led to severe defects in conidiation on different media and resulted in the formation of smaller and less compact pellets with less septa in hyphal cells during submerged fermentation. Compared with the WT, the ΔchsA mutants exhibited less chitin content, reduced growth under the stresses of cell wall-disturbing and oxidative agents, more released protoplasts, a thicker conidial wall, decreased production of amylases, pectinases, cellulases, and malic acid, and increased citric acid production. However, ΔchsA mutants displayed insignificant changes in their sensitivity to osmotic agents and infection ability on apple. These findings concurred with the alteration in the transcript levels and enzymatic activities of some phenotype-related genes. Conclusively, ChsA is important for cell wall integrity and mycelial morphology, and acts as a positive regulator of conidiation, cellular responses to oxidative stresses, and the production of malic acid and some enzymes, but negatively regulates the citric acid production in A. niger.

Leveraging Summary Guidance on Medical Report Summarization.

This study presents three deidentified large medical text datasets, named DISCHARGE, ECHO and RADIOLOGY, which contain 50 K, 16 K and 378 K pairs of report and summary that are derived from MIMIC-III, respectively. We implement convincing baselines of automated abstractive summarization on the created datasets with pre-trained encoder-decoder language models, including BERT2BERT, BERTShare, RoBERTaShare, Pegasus, ProphetNet, T5-large, BART and GSUM. Further, based on the BART model, we leverage the sampled summaries from the training set as prior knowledge guidance, for encoding additional contextual representations of the guidance with the encoder and enhancing the decoding representations in the decoder. The experimental results confirm the improvement of ROUGE scores and BERTScore made by the proposed method.

Genome-wide characterization of the tomato GASA family identifies SlGASA1 as a repressor of fruit ripening.

Gibberellins (GAs) play crucial roles in a wide range of developmental processes and stress responses in plants. However, the roles of GA-responsive genes in tomato (Solanum lycopersicum) fruit development remain largely unknown. Here, we identify 17 GASA (Gibberellic Acid-Stimulated Arabidopsis) family genes in tomato. These genes encode proteins with a cleavable signal peptide at their N terminus and a conserved GASA domain at their C terminus. The expression levels of all tomato GASA family genes were responsive to exogenous GA treatment, but adding ethylene eliminated this effect. Comprehensive expression profiling of SlGASA family genes showed that SlGASA1 follows a ripening-associated expression pattern, with low expression levels during fruit ripening, suggesting it plays a negative role in regulating ripening. Overexpressing SlGASA1 using a ripening-specific promoter delayed the onset of fruit ripening, whereas SlGASA1-knockdown fruits displayed accelerated ripening. Consistent with their delayed ripening, SlGASA1-overexpressing fruits showed significantly reduced ethylene production and carotenoid contents compared to the wild type. Moreover, ripening-related genes were downregulated in SlGASA1-overexpressing fruits but upregulated in SlGASA1-knockdown fruits compared to the wild type. Yeast two-hybrid, co-immunoprecipitation, transactivation, and DNA pull-down assays indicated that SlGASA1 interacts with the key ripening regulator FRUITFULL1 and represses its activation of the ethylene biosynthesis genes ACS2 and ACO1. Our findings shed new light on the role and mode of action of a GA-responsive gene in tomato fruit ripening.

Metagenomic next-generation sequencing for identification of central nervous system pathogens in HIV-infected patients.

Although considerable interest in metagenomic next-generation sequencing (mNGS) has been attracted in recent years, limited data are available regarding the performance of mNGS in HIV-associated central nervous system (CNS) infection. Here, we conducted a retrospectively analyzing of the cerebrospinal fluid (CSF) mNGS reports and other clinical data from 80 HIV-infected patients admitted to the Second Hospital of Nanjing, China from March, 2018 to March, 2022. In our study, CSF mNGS reported negative result, mono-infection, and mixed infection in 8.8, 36.2, and 55% of the patients, respectively. Epstein-Barr virus (EBV), positive in 52.5% of samples, was the most commonly reported pathogen, followed by cytomegalovirus (CMV), John Cunningham virus (JCV), torque teno virus (TTV), cryptococcus neoformans (CN), toxoplasma Gondii (TE), and mycobacterium tuberculosis (MTB). 76.2% of the EBV identification and 54.2% of the CMV identification were not considered clinically important, and relative less sequence reads were reported in the clinical unimportant identifications. The clinical importance of the presence of TTV in CSF was not clear. Detection of JCV, CN, or TE was 100% suggestive of specific CNS infection, however, 60% of the MTB reports were considered contamination. Moreover, of the 44 (55%) mixed infections reported by mNGS, only 4 (5%) were considered clinical important, and mNGS failed to identify one mixed infection. Additionally, except for MTB, CSF mNGS tended to have high sensitivity to identify the above-mentioned pathogens (almost with 100% sensitivity). Even all the diagnostic strategies were evaluated, the cause of neurological symptoms remained undetermined in 6 (7.5%) patients. Overall, our results suggest that mNGS is a very sensitive tool for detecting common opportunistic CNS pathogen in HIV-infected patients, although its performance in CNS tuberculosis is unsatisfactory. EBV and CMV are commonly detected by CSF mNGS, however, the threshold of a clinical important detection remains to be defined.

Clinical features and 18F-FDG PET/CT for distinguishing of malignant lymphoma from inflammatory lymphadenopathy in HIV-infected patients.

BACKGROUND: It is vital to distinguish between inflammatory and malignant lymphadenopathy in human immunodeficiency virus (HIV) infected individuals. The purpose of our study was to differentiate the variations in the clinical characteristics of HIV patients, and apply 18F-FDG PET/CT parameters for distinguishing of malignant lymphoma and inflammatory lymphadenopathy in such patients. METHODS: This retrospective cross-sectional study included 59 consecutive HIV-infected patients who underwent whole-body 18F-FDG PET/CT. Of these patients, 37 had biopsy-proven HIV-associated lymphoma, and 22 with HIV-associated inflammatory lymphadenopathy were used as controls. The determined parameters were the maximum of standard uptake value (SUVmax), SUVmax of only lymph nodes (SUVLN), the most FDG-avid lesion-to-liver SUVmax ratio (SURmax), laboratory examinations and demographics. The optimal cut-off of 18F-FDG PET/CT value was analyzed by receiver operating characteristic curve (ROC). RESULTS: Considering the clinical records, the Karnofsky Performance Status (KPS) scores in patients with inflammatory lymphadenopathy were obviously higher than those in patients with malignant lymphoma (P = 0.015), whereas lymphocyte counts and lactate dehydrogenase (LDH) were obviously lower (P = 0.014 and 0.010, respectively). For the 18F-FDG PET/CT imaging, extra-lymphatic lesions, especially digestive tract and Waldeyer's ring, occurred more frequently in malignant lymphoma than inflammatory lymphadenopathy. Furthermore, the SURmax and SUVLN in malignant lymphoma were markedly higher than those in inflammatory lymphadenopathy (P = 0.000 and 0.000, respectively). The cut-off point of 3.1 for SURmax had higher specificity (91.9%) and relatively reasonable sensitivity (68.2%) and the cut-off point of 8.0 for the SUVLN had high specificity (89.2%) and relatively reasonable sensitivity (63.6%). CONCLUSION: Our study identified the distinctive characteristics of the clinical manifestations, the SURmax, SUVLN and detectability of extra-lymphatic lesions on 18F-FDG PET, and thus provides a new basis for distinguishing of malignant lymphoma from inflammatory lymphadenopathy in HIV-infected patients.

Prognostic usefulness of clinical features and pretreatment 18F-FDG PET/CT metabolic parameters in patients with angiosarcoma.

Background: To investigate the prognostic value of clinical features and metabolic parameters in pretreatment 18F-2-fluoro-2-deoxy-D-glucose (18F-FDG) positron emission tomography/X-ray computed tomography (PET/CT) scans of patients with angiosarcoma, a rare neoplasm that has not been well characterized. Methods: In this retrospective study, 19 patients with a histopathologically confirmed diagnosis of angiosarcoma who had undergone pretreatment 18F-FDG PET/CT scans were enrolled. We recorded the age at presentation, sex, underlying diseases, sites of primary tumors, Karnofsky Performance Status (KPS) score, Eastern Cooperative Oncology Group (ECOG) score, time from onset to diagnosis, laboratory examinations, sites and sizes of primary tumors, treatment modalities, histologic features and American Joint Committee on Cancer (AJCC) stage, maximum standardized uptake value (SUVmax), average SUV (SUVavg), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of primary tumors and the whole body. Univariate and multivariate survival analyses for overall survival were performed according to the metabolic parameters and other clinical variables. Results: Patients ranged in age from 27 to 79 years (median: 59 years) with different angiosarcoma types covering all tumor grades and subtypes. Seven (7/19) patients had anemia of varying degrees of severity. Lymph node metastases (n=10) and/or distant metastases (n=11) of angiosarcoma were common. Bone or bone marrow (10/19) and lung (8/19) were the most common distant metastatic organs. Patients with bone metastases, low hemoglobin levels and high ferritin levels had significantly poorer overall survival than those with non-bone metastases, normal hemoglobin levels and normal ferritin levels by the log-rank test, with P values of 0.027, 0.030 and 0.015, respectively. Patients with multiple organ metastases had significantly poorer overall survival than those with single organ metastasis (log-rank P=0.008). In multivariate survival analysis, only whole-body metabolic tumor volume using SUVmax cut-off value of 2.5 (wMTV2.5) was a significant independent prognostic factor. For wMTV2.5, 870.3 cm3 was the best cut-off point to discriminate between a good and poor prognosis (log-rank P=0.01). Conclusions: The systemic 18F-FDG PET/CT with high sensitivity and specificity has significant advantages in the evaluation of angiosarcoma, particularly in detecting occult metastases. Bone metastases on 18F-FDG PET/CT, low hemoglobin levels and high ferritin levels were all associated with a poorer prognosis. MTV2.5 of the whole body is a significant independent metabolic prognostic factor for overall survival in patients with angiosarcoma.

18F-Choline PET Detected the Third Ventricle Craniopharyngioma.

ABSTRACT: Craniopharyngiomas are rare tumors of low histological malignancy (World Health Organization grade I) in the sellar and suprasellar region of the brain. We report a case of the third ventricular craniopharyngioma detected using 18F-choline PET/CT in a 43-year-old man. MRI of the brain revealed an intense gadolinium enhancement focus in the same area. Histology revealed characteristics of papillary craniopharyngioma. Our findings suggest that craniopharyngioma should be included in the differential diagnosis of 18F-choline-avid brain lesions.

WTIP upregulates FOXO3a and induces apoptosis through PUMA in acute myeloid leukemia.

Acute myeloid leukemia (AML) is an aggressive and heterogeneous clonal hematologic malignancy for which novel therapeutic targets and strategies are required. Emerging evidence suggests that WTIP is a candidate tumor suppressor. However, the molecular mechanisms of WTIP in leukemogenesis have not been explored. Here, we report that WTIP expression is significantly reduced both in AML cell lines and clinical specimens compared with normal controls, and low levels of WTIP correlate with decreased overall survival in AML patients. Overexpression of WTIP inhibits cell proliferation and induces apoptosis both in vitro and in vivo. Mechanistic studies reveal that the apoptotic function of WTIP is mediated by upregulation and nuclear translocation of FOXO3a, a member of Forkhead box O (FOXO) transcription factors involved in tumor suppression. We further demonstrate that WTIP interacts with FOXO3a and transcriptionally activates FOXO3a. Upon transcriptional activation of FOXO3a, its downstream target PUMA is increased, leading to activation of the intrinsic apoptotic pathway. Collectively, our results suggest that WTIP is a tumor suppressor and a potential target for therapeutic intervention in AML.

Metagenomic Next-Generation Sequencing vs. Traditional Microbiological Tests for Diagnosing Varicella-Zoster Virus Central Nervous System Infection.

BACKGROUND: Unbiased metagenomic next-generation sequencing (mNGS) detects pathogens in a target-independent manner. It is not well-understood whether mNGS has comparable sensitivity to target-dependent nucleic acid test for pathogen identification. METHODS: This study included 31 patients with chickenpox and neurological symptoms for screening of possible varicella-zoster virus (VZV) central nervous system (CNS) infection. Microbiological diagnosing of VZV cerebrospinal fluid (CSF) infection was performed on stored CSF samples using mNGS, quantitative and qualitative VZV-specific PCR assays, and VZV IgM antibodies test. RESULTS: The median age was 30.0 [interquartile range (IQR), 24.3-33.3] years. 51.6% of the patients were men. About 80.6% of the patients had normal CSF white blood cell counts (≤ 5 × 106/L). VZV IgM antibodies presented in 16.1% of the CSF samples, and nucleic acids were detectable in 16.1 and 9.7% using two different VZV-specific real-time PCR protocols. Intriguingly, maximal identification of VZV elements was achieved by CSF mNGS (p = 0.001 and p = 007; compared with qualitative PCR and VZV IgM antibody test, respectively), with sequence reads of VZV being reported in 51.6% (16/31) of the CSF samples. All VZV PCR positive samples were positive when analyzed by mNGS. Of note, human betaherpesvirus 6A with clinical significance was unexpectedly detected in one CSF sample. CONCLUSIONS: Our study suggests that CSF mNGS may have higher sensitivity for VZV detection than CSF VZV PCR and antibody tests, and has the advantage of identifying unexpected pathogens.

Study of low-dose PET image recovery using supervised learning with CycleGAN.

PET is a popular medical imaging modality for various clinical applications, including diagnosis and image-guided radiation therapy. The low-dose PET (LDPET) at a minimized radiation dosage is highly desirable in clinic since PET imaging involves ionizing radiation, and raises concerns about the risk of radiation exposure. However, the reduced dose of radioactive tracers could impact the image quality and clinical diagnosis. In this paper, a supervised deep learning approach with a generative adversarial network (GAN) and the cycle-consistency loss, Wasserstein distance loss, and an additional supervised learning loss, named as S-CycleGAN, is proposed to establish a non-linear end-to-end mapping model, and used to recover LDPET brain images. The proposed model, and two recently-published deep learning methods (RED-CNN and 3D-cGAN) were applied to 10% and 30% dose of 10 testing datasets, and a series of simulation datasets embedded lesions with different activities, sizes, and shapes. Besides vision comparisons, six measures including the NRMSE, SSIM, PSNR, LPIPS, SUVmax and SUVmean were evaluated for 10 testing datasets and 45 simulated datasets. Our S-CycleGAN approach had comparable SSIM and PSNR, slightly higher noise but a better perception score and preserving image details, much better SUVmean and SUVmax, as compared to RED-CNN and 3D-cGAN. Quantitative and qualitative evaluations indicate the proposed approach is accurate, efficient and robust as compared to other state-of-the-art deep learning methods.

Overexpression of bHLH95, a basic helix-loop-helix transcription factor family member, impacts trichome formation via regulating gibberellin biosynthesis in tomato.

Trichomes are epidermal protuberances on aerial parts of plants known to play an important role in biotic and abiotic stresses. To date, our knowledge of the regulation of trichome formation in crop species is very limited. Through phenotyping of the Solanum pennellii×S. lycopersicum (cv. M82) introgression population, we identified the SlbHLH95 transcription factor as a negative regulator of trichome formation in tomato. In line with this negative role, SlbHLH95 displayed a very low expression in stems where trichomes are present at high density. Overexpression of SlbHLH95 resulted in a dramatically reduced trichome density in stems and a significant down-regulation of a set of trichome-related genes. In addition to the lower trichome density, overexpressing lines also showed pleiotropic alterations affecting both vegetative and reproductive development. While most of these phenotypes were reminiscent of gibberellin (GA)-deficient phenotypes, expression studies showed that two GA biosynthesis genes, SlGA20ox2 and SlKS5, are significantly down-regulated in SlbHLH95-OE plants. Moreover, in line with a decrease in active GA content, the glabrous and dwarf phenotypes were rescued by exogenous GA treatment. In addition, yeast one-hybrid and transactivation assays revealed that SlbHLH95 represses the expression of SlGA20ox2 and SlKS5 via direct binding to their promoters. Taken together, our study established a link between SlbHLH95, GA, and trichome formation, and uncovered the role of this gene in modulating GA biosynthesis in tomato.

Atherosclerosis and Nanomedicine Potential: Current Advances and Future Opportunities.

Atherosclerosis is the leading inducement of cardiovascular diseases, which ranks the first cause of global deaths. It is an arterial disease associated with dyslipidemia and changes in the composition of the vascular wall. Besides invasive surgical strategy, the current conservative clinical treatment for atherosclerosis falls into two categories, lipid regulating-based therapy and antiinflammatory therapy. However, the existing strategies based on conventional drug delivery systems have shown limited efficacy against disease development and plenty of side effects. Nanomedicine has great potential in the development of targeted therapy, controlled drug delivery and release, the design of novel specific drugs and diagnostic modalities, and biocompatible scaffolds with multifunctional characteristics, which has led to an evolution in the diagnosis and treatment of atherosclerosis. This paper will focus on the latest nanomedicine strategies for atherosclerosis diagnosis and treatment as well as discussing the potential therapeutic targets during atherosclerosis progress, which could form the basis of development of novel nanoplatform against atherosclerosis.

Peach Carboxylesterase PpCXE1 Is Associated with Catabolism of Volatile Esters.

Peach fruit volatile acetate esters impact consumer sensory preference and contribute to defense against biotic stresses. Previous studies showed that alcohol acyltransferase (AAT) family PpAAT1 is correlated with volatile ester formation in peach fruits. However, fruits also contain carboxylesterase (CXE) enzymes that hydrolyze esters. The functions of this family with regard to volatile ester content has not been explored. Here, we observed that content of acetate ester was negatively correlated with expression of PpCXE1. Recombinant PpCXE1 protein exhibited hydrolytic activity toward acetate esters present in peach fruit. Kinetic analysis showed that PpCXE1 showed the highest catalytic activity toward E-2-hexenyl acetate. Subcellular localization demonstrated that PpCXE1 is present in the cytoplasm. Transient expression in peach fruit and stable overexpression in tomato fruit resulted in significant reduction of volatile esters in vivo. Taken together, the results indicate that PpCXE1 expression is associated with catabolism of volatile acetate esters in peach fruit.

PET Imaging on Dynamic Metabolic Changes after Combination Therapy of Paclitaxel and the Traditional Chinese Medicine in Breast Cancer-Bearing Mice.

PURPOSE: The aim of the study was to non-invasively evaluate the anticancer activity of a traditional Chinese medicine-Huaier, combined with paclitaxel (PTX) in breast cancer bearing mice by detecting dynamic metabolic changes with positron emission tomography (PET). PROCEDURES: Balb/c nude mice were randomly divided into one of the four groups: Huaier, PTX, PTX + Huaier, or the control. PET imaging with 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) was performed to monitor the metabolic changes in BT474 (luminal B) and MDA-MB-231 (triple-negative) breast cancer xenografts. Immunohistochemistry (IHC) study was performed immediately after the final PET scan to assess the expressions of phosphatidylinositol 3-kinase (PI3K), phospho-AKT (p-AKT), caspase-3, and vascular endothelial growth factor (VEGF). RESULTS: Compared to the control group, [18F]FDG accumulation demonstrated a significant decrease in PTX + Huaier (p < 0.01) or Huaier group (p < 0.05), which was consistent to the decreased expression of PI3K (p < 0.05) and p-AKT (p < 0.05) in the breast cancer xenografts. CONCLUSION: The therapeutic effect of Huaier combined with PTX was superior than the PTX alone in BT474 and MDA-MB-231 breast cancer-bearing mice. [18F]FDG PET imaging could be a potential non-invasive approach to assess the metabolic changes after chemotherapy combined with traditional Chinese medicine in the breast cancer.

In Vivo Dynamic Metabolic Changes After Transplantation of Induced Pluripotent Stem Cells for Ischemic Injury.

This study aimed to investigate in vivo dynamic metabolic changes after transplantation of induced pluripotent stem cells (iPSCs) and iPSC-derived enriched cardiomyocytes (iPSC-CMs) in a rat model of ischemic injury. METHODS: Serial 18F-FDG PET, echocardiographic, immunohistochemical, and immunofluorescence studies were performed after transplantation of iPSCs and iPSC-CMs and compared with embryonic stem cells (ESCs), ESC-CMs, and a phosphate-buffered saline control group of rats with myocardial infarction. RESULTS: Increased glucose metabolism in periinfarct areas and improved myocardial function were observed in the stem cell transplantation groups compared with the control group, and serial immunofluorescence and immunohistochemical results exhibited the survival and migration of stem cells during the study period. CONCLUSION: Serial 18F-FDG PET and echocardiographic imaging studies demonstrated the dynamic metabolic changes and recovery of myocardial function after stem cell transplantation. 18F-FDG PET could be a potential approach to evaluating spatiotemporal dynamic metabolic changes in vivo after transplantation of iPSCs or iPSC-CMs for ischemic injury.

Molecular, Functional, and Structural Imaging of Major Depressive Disorder.

Major depressive disorder (MDD) is a significant cause of morbidity and mortality worldwide, correlating with genetic susceptibility and environmental risk factors. Molecular, functional, and structural imaging approaches have been increasingly used to detect neurobiological changes, analyze neurochemical correlates, and parse pathophysiological mechanisms underlying MDD. We reviewed recent neuroimaging publications on MDD in terms of molecular, functional, and structural alterations as detected mainly by magnetic resonance imaging (MRI) and positron emission tomography. Altered structure and function of brain regions involved in the cognitive control of affective state have been demonstrated. An abnormal default mode network, as revealed by resting-state functional MRI, is likely associated with aberrant metabolic and serotonergic function revealed by radionuclide imaging. Further multi-modal investigations are essential to clarify the characteristics of the cortical network and serotonergic system associated with behavioral and genetic variations in MDD.