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Abstract Background Cardiomyocytes derived from pluripotent stem cells (PSC-CMs) have been widely accepted as a promising cell source for cardiac drug screening and heart regeneration therapies. However, unlike adult cardiomyocytes, the underdeveloped structure, the immature electrophysiological properties and metabolic phenotype of PSC-CMs limit their application. This project aimed to study the role of the transient receptor potential ankyrin 1 (TRPA1) channel in regulating the maturation of embryonic stem cell-derived cardiomyocytes (ESC-CMs). Methods The activity and expression of TRPA1 in ESC-CMs were modulated by pharmacological or molecular approaches. Knockdown or overexpression of genes was done by infection of cells with adenoviral vectors carrying the gene of interest as a gene delivery tool. Immunostaining followed by confocal microscopy was used to reveal cellular structure such as sarcomere. Staining of mitochondria was performed by MitoTracker staining followed by confocal microscopy. Calcium imaging was performed by fluo-4 staining followed by confocal microscopy. Electrophysiological measurement was performed by whole-cell patch clamping. Gene expression was measured at mRNA level by qPCR and at protein level by Western blot. Oxygen consumption rates were measured by a Seahorse Analyzer. Results TRPA1 was found to positively regulate the maturation of CMs. TRPA1 knockdown caused nascent cell structure, impaired Ca2+ handling and electrophysiological properties, and reduced metabolic capacity in ESC-CMs. The immaturity of ESC-CMs induced by TRPA1 knockdown was accompanied by reduced mitochondrial biogenesis and fusion. Mechanistically, we found that peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), the key transcriptional coactivator related to mitochondrial biogenesis and metabolism, was downregulated by TRPA1 knockdown. Interestingly, overexpression of PGC-1α ameliorated the halted maturation induced by TRPA1 knockdown. Notably, phosphorylated p38 MAPK was upregulated, while MAPK phosphatase-1 (MKP-1), a calcium-sensitive MAPK inhibitor, was downregulated in TRPA1 knockdown cells, suggesting that TRPA1 may regulate the maturation of ESC-CMs through MKP-1-p38 MAPK-PGC-1α pathway. Conclusions Taken together, our study reveals the novel function of TRPA1 in promoting the maturation of CMs. As multiple stimuli have been known to activate TRPA1, and TRPA1-specific activators are also available, this study provides a novel and straightforward strategy for improving the maturation of PSC-CMs by activating TRPA1. Since a major limitation for the successful application of PSC-CMs for research and medicine lies in their immature phenotypes, the present study takes a big step closer to the practical use of PSC-CMs. Graphical abstract

Pluripotent stem cells (PSCs) can undergo unlimited self-renewal and can differentiate into all the cell types present in our body, including cardiomyocytes. Therefore, PSCs can be an excellent source of cardiomyocytes for future regenerative medicine and medical research studies. However, cardiomyocytes obtained from PSC differentiation culture are regarded as immature structurally, electrophysiologically, metabolically, and functionally. Mitochondria are organelles responsible for various cellular functions such as energy metabolism, different catabolic and anabolic processes, calcium fluxes, and various signaling pathways. Cells can respond to cellular needs to increase the mitochondrial mass by mitochondrial biogenesis. On the other hand, cells can also degrade mitochondria through mitophagy. Mitochondria are also dynamic organelles that undergo continuous fusion and fission events. In this review, we aim to summarize previous findings on the changes of mitochondrial biogenesis, mitophagy, and mitochondrial dynamics during the maturation of cardiomyocytes. In addition, we intend to summarize whether changes in these processes would affect the maturation of cardiomyocytes. Lastly, we aim to discuss unanswered questions in the field and to provide insights for the possible strategies of enhancing the maturation of PSC-derived cardiomyocytes.

[Objectives] The paper was to identify Alternaría alternata causing leaf spot disease on Huangdi banana in China. [Methods] Fungal isolates were isolated and identified by morphological features, molecular identification and pathogenicity test. [Results] There were light to dark brown, tiny oval spots on leaves. The causal agent isolated from affected leaves was identified as A. alternata based on the morphological properties, coupled with sequence analyses of the internal transcribed spacer (IIS) region, large subunit ribosomal DNA (LSU rD-NA) and the translation elongation factor 1-alpha (TEF-la) gene. Koch's postulates were fuEilled by successful re-isolation of pathogen from the artificial inoculated leaves. [ Conclusions] To our knowledge, this is the first report of leaf spot caused by A. alternata on Huangdi banana in China. The identification of A. alternata as the causal agent of the observed leaf spot disease on Huangdi banana is critical to the prevention and control of this disease in the future. [ABSTRACT FROM AUTHOR]

[Objectives] The paper was to study molecular characterization, morphology and pathogenicity of Curvularia pseudobrachyspora, a new causal agent of leaf spot on banana. [Methods] Banana (Musa acuminate') leaves with streaks or long ellipse-shaped lesions were sampled in an orchard of Danzhou City, Hainan Province, China in 2021. Fungus isolates were isolated from the diseased tissues and further identified as C. pseudobrachyspora based on morphological characteristics of colony, conidiophore and spore, phylogenetic analyses of the ITS region, GAP DP and TET-la genes. [Results] In the pathogenicity test, the fungus re-isolated from inoculated leaves with necrotic lesions was identified morphologically and molecularly, fulfilling Koch's postulates. [Conclusions] C. pseudobrachyspora is a new pathogen causing leaf spot of banana in China and the world. [ABSTRACT FROM AUTHOR]

[Objectives] The study was to confirm the etiological agent of leaf spot on banana in Yunnan Province of China. [Methods] Fungus isolates were isolated from the diseased tissues, and cultured to observe the morphological characteristics of colony and spore. Furthermore, phylogenetic analyses and pathogenicity test were also conducted to confirm the pathogen. [Results] The fungus isolated from the diseased tissues was identified as Neopestalotiopsis clavispora. [Conclusions] N. clavispora is a new pathogen causing leaf spot of banana. This research provides the first description of N. clavispora as a causal agent on banana in China, and adds new insights related to the host range of N. clavispora. [ABSTRACT FROM AUTHOR]

[Objective] The paper was to screen effective fungicides to control Cordana leaf spot caused by Neocordana musae. [Method] The toxicities of six fungicides against mycelial growth of N. musae were measured by the method of mycelium growth inhibition. [Result] The average EC50 values of six fungicides against mycelial growth ranged from 0.102 9 to 504.065 µg/mL. Among them, 22.5% picoxystrobin SC and 12.5% epoxiconazole SC showed strong inhibitors' activity on mycelial growth, with the average EC% values of 0.102 9 and 0.685 1 µg/mL, respectively; followed by 50% thiophanate-methyl SC, with an average EC50 value of 1.993. 80% Azoxystrobin WG showed a relatively low sensitivity against N. musae, with an average EC50 value of 504.046. [Conclusion] The six fungicides tested have great value in preventing and controlling Cordana leaf spot. 22.5% Picoxystrobin SC, 12.5% epoxiconazole SC and 50% thiophanate-methyl SC have better inhibitory activities on mycelial growth of N. musae, and can be further used in field trials. [ABSTRACT FROM AUTHOR]

[Objectives] The paper was to identify the causal agent of leaf spot of banana in Hainnan, China. [Methods] Fungus isolates were isolated from the diseased tissues, and morphological characteristics of colony and spore were observed. Furthermore, phylogenetic analyses and pathogenicity test were conducted to confirm the pathogen. [ Results] The fungus isolates from the diseased tissues was identified as Curvularia geniculata. [Conclusions] C. geniculata is a new pathogen causing leaf spot of banana in Hainan, China. This finding will help to broaden the distribution and host range of C. geniculata, indicating that it poses potential damage to banana in China. [ABSTRACT FROM AUTHOR]

Abstract Background The fall armyworm Spodoptera frugiperda is a highly destructive agricultural pest that primarily damages maize in China. However, there were no reports of S. frugiperda damage to banana until it was observed on bananas in the wild. This suggested that banana crops may be potential hosts of the pest. To clarify the fitness and potential impact of S. frugiperda on banana, this study analysed the survival and development of S. frugiperda fed on bananas in the laboratory and constructed age-stage and two-sex life tables. Results Larvae of S. frugiperda fed on bananas completed their life cycles and produced fertile offspring, but the larvae had eight instars and presented longer developmental duration, slower population growth, and lower body weight than maize-fed larvae. Furthermore, the banana-fed S. frugiperda had longer adult longevity and preoviposition periods than the maize-fed larvae, while the opposite tendency was observed for oviposition days and egg production. Based on age-stage and two-sex life tables, the survival probability at each stage of S. frugiperda fed on bananas was lower than that of maize-fed larvae, and banana-fed S. frugiperda showed lower reproductive capacity. Conclusions Although banana is not an ideal host for the fall armyworm, it may be colonized by the species in situations in which the population density is high or the preferred host is scarce. Therefore, it is essential to prevent the pest from transferring to bananas and thereby increasing the number of sources of outbreaks. Graphical Abstract

Introduction: Paternal smoking associated with childhood overweight and obesity has been a concern, but studies have not investigated smoking exposure and smoking details. We investigated the association of exposures from paternal smoking as well as smoking details on offspring overweight/obesity. Methods: A total of 4,513 children (aged 7–8 years) in Shenzhen were enrolled. Four different exposures from paternal smoking as well as smoking quantity, duration of smoking, and age of starting smoking details were the exposure variables and demographic characteristics, and circumstances of birth, dietary intake, lifestyle, and nonpaternal-smoking exposure were covariates in the logistic regression analysis to determine the effect of paternal smoking on childhood overweight/obesity, estimating odds ratios (ORs), and 95% confidence intervals (CIs). Results: Paternal smoking was positively associated with childhood overweight/obesity (p < 0.05). Moreover, only preconception exposure, and both pre- and postconception exposure were significantly associated with childhood overweight/obesity (OR 1.54 [95% CI: 1.14–2.08] and OR 1.73 [95% CI: 1.14–2.61], respectively), restricted to boys but not girls. Furthermore, for children with only preconception paternal-smoking exposure, the dose-response relation was positive between smoking quantity, duration of smoking, age at starting, and overweight/obesity for boy offspring (p trend 0.05). Conclusions: Our findings suggest that paternal smoking is associated with boys’ overweight/obesity, and this association may be due to the paternal-smoking exposure before conception rather than the postnatal exposure to paternal smoking. Reducing paternal-smoking exposure before conception might help reduce overweight/obesity in boys.