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Key message: Hydrogen sulfide improved cold resistance of tomato fruits by regulating energy metabolism and delaying cell wall degradation, thereby alleviating the damage of cold storage on fruits. Postharvest cold storage in tomato fruits extended shelf life but caused the appearance of chilling injury (CI), appeared by softness and spots on the surface of the fruits. These changes were linked closely with energy and cell wall metabolisms. Hydrogen sulfide (H2S), as the gaseous fresh-keeping regulator, was used in the present study to investigate the effects of H2S on energy and cell wall metabolisms in tomato fruits during cold storage. Fruits after harvest were fumigated with different concentrations (0, 0.5, 1, 1.5 mM) of sodium hydrosulfide (NaHS) solution as H2S honor for 24 h and stored at 4 °C for 25 days. The results showed that 1 and 1.5 mM NaHS solution fumigation promoted the accumulation of endogenous H2S, followed by the increase in L-cysteine desulfurase (LCD) and D-cysteine desulfurase (DCD) activities in fruits during cold storage. It was also found that 1 and 1.5 mM NaHS treatments improved H+-ATPase, Ca2+-ATPase, cytochrome C oxidase (CCO), and succinic dehydrogenase (SDH) activities. Moreover, the contents of cellulose and hemicellulose were increased by 1 and 1.5 mM NaHS, following down-regulated activities of cellulase (CL), pectin lyase (PL), α-mannosidase (α-man) and β-Galactosidase (β-Gal) and down-regulated expression of PL1, PL8, MAN4 and MAN7 genes. Thus, H2S alleviates CI led by cold storage in tomato fruits via regulating energy and cell wall metabolisms. [ABSTRACT FROM AUTHOR]

Background: Drought is thought to be a major abiotic stress that dramatically limits tomato growth and production. As signal molecule, melatonin (MT) and carbon monoxide (CO) can enhance plant stress resistance. However, the effect and underlying mechanism of CO involving MT-mediated drought resistance in seedling growth remains unknown. In this study, tomato (Solanum lycopersicum L. 'Micro-Tom') seedlings were used to investigate the interaction and mechanism of MT and CO in response to drought stress. Results: The growth of tomato seedlings was inhibited significantly under drought stress. Exogenous MT or CO mitigated the drought-induced impairment in a dose-dependent manner, with the greatest efficiency provided by 100 and 500 µM, respectively. But application of hemoglobin (Hb, a CO scavenger) restrained the positive effects of MT on the growth of tomato seedlings under drought stress. MT and CO treatment promoted chlorophyll a (Chl a) and chlorophyll a (Chl b) accumulations. Under drought stress, the intermediate products of chlorophyll biosynthesis such as protoporphyrin IX (Proto IX), Mg-protoporphyrin IX (Mg-Proto IX), potochlorophyllide (Pchlide) and heme were increased by MT or CO, but uroporphyrinogen III (Uro III) content decreased in MT-treated or CO-treated tomato seedlings. Meanwhile, MT or CO up-regulated the expression of chlorophyll and heme synthetic-related genes SlUROD, SlPPOX, SlMGMT, SlFECH, SlPOR, SlChlS, and SlCAO. However, the effects of MT on chlorophyll biosynthesis were almost reversed by Hb. Conclusion: The results suggested that MT and CO can alleviate drought stress and facilitate the synthesis of Chl and heme in tomato seedlings. CO played an essential role in MT-enhanced drought resistance via facilitating chlorophyll biosynthesis pathway. [ABSTRACT FROM AUTHOR]

Background: Wernicke encephalopathy (WE) is a devastating acute or subacute neurological disorder caused by thiamine deficiency. Wernicke encephalopathy is characterized by the triad of ocular signs, cerebellar dysfunction, and confusion. Visual loss and hearing loss are less common findings in WE. Here, we report a case of Wernicke encephalopathy in a nonalcoholic liver cirrhosis patient who presented with acute bilateral deafness and bilateral blindness. Case presentation: A 60-year-old Chinese man presented with a history of bilateral blindness and bilateral hypoacousia for 3 days. He had a history of liver cirrhosis and chronic hepatitis C virus infection and did not have a habit of alcohol consumption. Ophthalmologic and otologic examinations showed no obvious abnormalities. MRI findings revealed symmetric fluid-attenuated inversion recovery (FLAIR) hyperintensities in the bilateral medial dorsal thalamus, periventricular region around the third ventricle and tectum, and dorsal medulla oblongata. One day after hospitalization, the patient developed a mild coma. Based on the laboratory and neuroimaging findings, we diagnosed the patient with Wernicke encephalopathy. He soon regained consciousness after administration of thiamine. Both his visual acuity and his hearing function improved gradually. Conclusions: We suggest that Wernicke encephalopathy can present with bilateral blindness and bilateral deafness. [ABSTRACT FROM AUTHOR]

Melatonin (MT) and nitric oxide (NO) act as signaling molecules that can enhance cadmium (Cd) stress resistance in plants. However, little information is available about the relationship between MT and NO during seedling growth under Cd stress. We hypothesize that NO may be involved in how MT responds to Cd stress during seedling growth. The aim of this study is to evaluate the relationship and mechanism of response. The results indicate that different concentrations of Cd inhibit the growth of tomato seedlings. Exogenous MT or NO promotes seedling growth under Cd stress, with a maximal biological response at 100 μM MT or NO. The promotive effects of MT-induced seedling growth under Cd stress are suppressed by NO scavenger 2-4-carboxyphenyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide (cPTIO), suggesting that NO may be involved in MT-induced seedling growth under Cd stress. MT or NO decreases the content of hydrogen peroxide (H2O2), malonaldehyde (MDA), dehydroascorbic acid (DHA), and oxidized glutathione (GSSG); improves the content of ascorbic acid (AsA) and glutathione (GSH) and the ratios of AsA/DHA and GSH/GSSG; and enhances the activities of glutathione reductase (GR), monodehydroascorbic acid reductase (MDHAR), dehydroascorbic acid reductase (DHAR), ascorbic acid oxidase (AAO), and ascorbate peroxidase (APX) to alleviate oxidative damage. Moreover, the expression of genes associated with the ascorbate–glutathione (AsA-GSH) cycle and reactive oxygen species (ROS) are up-regulated by MT or NO under Cd conditions, including AAO, AAOH, APX1, APX6, DHAR1, DHAR2, MDHAR, and GR. However, NO scavenger cPTIO reverses the positive effects regulated by MT. The results indicate that MT-mediated NO enhances Cd tolerance by regulating AsA-GSH cycle and ROS metabolism. [ABSTRACT FROM AUTHOR]

Functional gastrointestinal disorders (FGIDs) are common among the aircrew due to their arduous working environment. This study investigated the prevalence of FGIDs in Chinese male pilots and assessed the effects of trigger factors on the FGIDs. A cross-sectional study including 212 male pilots was performed in a Chinese large civil airline company. FGIDs were diagnosed according to the Rome IV diagnostic criteria. The psychological performance, dietary pattern, sleep situation, and physical activity of the respondents were assessed. Logistic regression analysis and structural equation modeling were used to explore the association between these trigger factors and FGIDs. FGIDs were observed in 83 (39.22%) respondents, of which 31 (37.35%) had overlap syndromes. Age, flight level, flight time, high-salt food pattern, anxiety, and sleep performance were found to be associated with FGIDs (all P < 0.05). Stepwise logistic regression analysis revealed that the flight level (OR 0.59, 95% CI 0.31–0.080), high-salt food pattern (OR 2.31, 95% CI 1.28–4.16), and sleep performance (OR 2.39, 95% CI 1.11–5.14) were the influencing factors associated with FGIDs. Structural equation modeling confirmed the correlations between FGIDs and the occupational, dietary, and psychological factors with a reasonable fit. The preventive strategies were necessitated according to occupational and psychological characteristics. [ABSTRACT FROM AUTHOR]

Anthocyanins act as polyphenolic pigment that is ubiquitously found in plants. Anthocyanins play a role not only in health-promoting as an antioxidant, but also in protection against all kinds of abiotic and biotic stresses. Most recent studies have found that MYB transcription factors (MYB TFs) could positively or negatively regulate anthocyanin biosynthesis. Understanding the roles of MYB TFs is essential in elucidating how MYB TFs regulate the accumulation of anthocyanin. In the review, we summarized the signaling pathways medicated by MYB TFs during anthocyanin biosynthesis including jasmonic acid (JA) signaling pathway, cytokinins (CKs) signaling pathway, temperature-induced, light signal, 26S proteasome pathway, NAC TFs, and bHLH TFs. Moreover, structural and regulator genes induced by MYB TFs, target genes bound and activated or suppressed by MYB TFs, and crosstalk between MYB TFs and other proteins, were found to be vitally important in the regulation of anthocyanin biosynthesis. In this study, we focus on the recent knowledge concerning the regulator signaling and mechanism of MYB TFs on anthocyanin biosynthesis, covering the signaling pathway, genes expression, and target genes and protein expression. [ABSTRACT FROM AUTHOR]

In order to survive in extreme environments, plants have evolved multiple mechanisms, such as DNA methylation, to adapt to environmental stress. A large number of investigations indicate that abiotic stress triggers changes in DNA methylation, resulting in fluctuations of expression levels of stress-related genes, thereby enhancing stress tolerance in plants. This review summarized that DNA methylation in plants can enhance tolerance to abiotic stress, including nutrient, sulfur dioxide (SO 2), metal, temperature and osmotic stress. The dynamics of DNA methylation in plant under abiotic stress was discussed from the aspects of genome stability, gene expression, gene silencing and protein interaction. Moreover, several important pathways of methylation also are involved in response to stress. Firstly, methylation activated or inhibited gene expression and mediatted interaction of genes under abiotic stress. Secondly, the RNA-directed DNA methylation (RdDM) pathway can participate in gene expression. Third, up-regulation of DNA methylase and demethylase genes can also affect DNA methylation levels. Fourth, methylation mediated the response of plant antioxidant system. Fifth, DNA methylation had a potential regulatory role in plant cross-adaptation. Additionally, we summarized the methylation of abscisic acid and ethylene synthesis related-genes under stress. We also speculate that the interaction of methylation with other phytohormones can enhance plant stress resistance. Therefore, this review provides a better understanding of plant response to abiotic stress at the molecular level. • DNA methylation in plants can enhance tolerance to nutrient, sulfur dioxide, Aluminum, temperature and osmotic stress. [ABSTRACT FROM AUTHOR]

• MADS-box TFs regulate fleshy fruit ripening. • MADS-box TFs-medicated various pathways control such process. • Their targets, and how they interact to control the progression of ripening. Understanding the regulation of fleshy fruit ripening is biologically important and provides insights and opportunities for controlling the ripening time of fruit and improving fruit quality. MADS-box transcription factors (TFs) are key elements of the genetic networks controlling fruit ripening. In this review, we conclude that MADS-box TFs including RIN, FRUITFULL1 (FUL1), FRUITFULL2 (FUL2), TAGL1, MADS1, SlMBP8, SlMBP15, SlAGL11, SlCMB1, SlFYFL, etc. , regulate fleshy fruit ripening. The MADS-box TFs-medicated ethylene-dependent and independent, carotenoids biosynthesis, cell wall metabolism, gibberellin (GA) synthesis, and abscission pathways in controlling fleshy fruit ripening have been highlighted in this review. In addition, RIN and FUL1 act downstream of ethylene signaling that have been proposed during fruit ripening. Moreover, we also discuss the diversity of components in the control network, their targets, and how they interact to control the progression of ripening. This review will be useful for researchers engaged in fruit ripening around the globe. Further attention should be paid to relationships between MADS-box TFs and other TFs or ripening-associated proteins in ripening control. [ABSTRACT FROM AUTHOR]

Trehalose (Tre) plays a vital role in response to drought stress in plants but its regulatory mechanism remains unclear. Here, this study explores the mechanism of re-regulated drought tolerance during cucumber adventitious root formation. Our results indicate that 2 mM Tre displays remarkable drought alleviation in the aspect of root number, root length, fresh weight, and dry weight. Under drought stress, Tre could inhibit greatly the MDA, H 2 O 2 , and O 2 − accumulation, enhance obviously the activities of SOD, POD, and CAT enzymes and up-regulate significantly the transcript levels of SOD , POD , and CAT genes. Furthermore, Tre treatment also promotes Tre metabolism during drought stress: significantly increases starch and Tre contents and decreases glucose content, the biosynthesis enzymatic activity of the Tre metabolic pathway including TPS and TPP are enhanced and the activity of degradation enzyme THL is decreased, and corresponding genes TPS1 , TPS2 , TPPA , and TPPB are up-regulated. Tre significantly reversed the decrease caused by PEG in IAA, ethylene, ABA, and BR contents and the increase caused by PEG in GA 3 and KT contents. Collectively, Tre appears to be the effective treatment in counteracting the negative effects of drought stress during adventitious root formation by regulating ROS, Tre metabolisms and plant hormones. • Trehalose enhances drought stress resistance in cucumber during adventitious rooting. • Trehalose-medicated ROS improves drought stress resistance. • Trehalose alleviates cucumber drought stress by regulating trehalose metabolism. [ABSTRACT FROM AUTHOR]

Background: Gestational diabetes mellitus (GDM) is one type of diabetes that presents during pregnancy and significantly increases the risk of a number of adverse consequences for the fetus and mother. The microRNAs (miRNA) have recently been demonstrated to abundantly and stably exist in serum and to be potentially disease-specific. However, no reported study investigates the associations between serum miRNA and GDM. Methodology/Principal Findings: We systematically used the TaqMan Low Density Array followed by individual quantitative reverse transcription polymerase chain reaction assays to screen miRNAs in serum collected at 16-19 gestational weeks. The expression levels of three miRNAs (miR-132, miR-29a and miR-222) were significantly decreased in GDM women with respect to the controls in similar gestational weeks in our discovery evaluation and internal validation, and two miRNAs (miR-29a and miR-222) were also consistently validated in two-centric external validation sample sets. In addition, the knockdown of miR-29a could increase Insulin-induced gene 1 (Insig1) expression level and subsequently the level of Phosphoenolpyruvate Carboxy Kinase2 (PCK2) in HepG2 cell lines. Conclusions/Significance: Serum miRNAs are differentially expressed between GDM women and controls and could be candidate biomarkers for predicting GDM. The utility of miR-29a, miR-222 and miR-132 as serum-based non-invasive biomarkers warrants further evaluation and optimization. [ABSTRACT FROM AUTHOR]