Phosphatidic acid modulates MPK3- and MPK6-mediated hypoxia signaling in Arabidopsis.

Phosphatidic acid (PA) is an important lipid essential for several aspects of plant development and biotic and abiotic stress responses. We previously suggested that submergence induces PA accumulation in Arabidopsis thaliana; however, the molecular mechanism underlying PA-mediated regulation of submergence-induced hypoxia signaling remains unknown. Here, we showed that in Arabidopsis, loss of the phospholipase D (PLD) proteins PLDα1 and PLDδ leads to hypersensitivity to hypoxia, but increased tolerance to submergence. This enhanced tolerance is likely due to improvement of PA-mediated membrane integrity. PA bound to the mitogen-activated protein kinase 3 (MPK3) and MPK6 in vitro and contributed to hypoxia-induced phosphorylation of MPK3 and MPK6 in vivo. Moreover, mpk3 and mpk6 mutants were more sensitive to hypoxia and submergence stress compared with wild type, and fully suppressed the submergence-tolerant phenotypes of pldα1 and pldδ mutants. MPK3 and MPK6 interacted with and phosphorylated RELATED TO AP2.12, a master transcription factor in the hypoxia signaling pathway, and modulated its activity. In addition, MPK3 and MPK6 formed a regulatory feedback loop with PLDα1 and/or PLDδ to regulate PLD stability and submergence-induced PA production. Thus, our findings demonstrate that PA modulates plant tolerance to submergence via both membrane integrity and MPK3/6-mediated hypoxia signaling in Arabidopsis.

Integrated analysis of transcriptome and small RNAome reveals regulatory network of rapid and long-term response to heat stress in Rhododendron moulmainense.

MAIN CONCLUSION: The post-transcriptional gene regulatory pathway and small RNA pathway play important roles in regulating the rapid and long-term response of Rhododendron moulmainense to high-temperature stress. The Rhododendron plays an important role in maintaining ecological balance. However, it is difficult to domesticate for use in urban ecosystems due to their strict optimum growth temperature condition, and its evolution and adaptation are little known. Here, we combined transcriptome and small RNAome to reveal the rapid response and long-term adaptability regulation strategies in Rhododendron moulmainense under high-temperature stress. The post-transcriptional gene regulatory pathway plays important roles in stress response, in which the protein folding pathway is rapidly induced at 4 h after heat stress, and alternative splicing plays an important role in regulating gene expression at 7 days after heat stress. The chloroplasts oxidative damage is the main factor inhibiting photosynthesis efficiency. Through WGCNA analysis, we identified gene association patterns and potential key regulatory genes responsible for maintaining the ROS steady-state under heat stress. Finally, we found that the sRNA synthesis pathway is induced under heat stress. Combined with small RNAome, we found that more miRNAs are significantly changed under long-term heat stress. Furthermore, MYBs might play a central role in target gene interaction network of differentially expressed miRNAs in R. moulmainense under heat stress. MYBs are closely related to ABA, consistently, ABA synthesis and signaling pathways are significantly inhibited, and the change in stomatal aperture is not obvious under heat stress. Taken together, we gained valuable insights into the transplantation and long-term conservation domestication of Rhododendron, and provide genetic resources for genetic modification and molecular breeding to improve heat resistance in Rhododendron.

MYB30 integrates light signals with antioxidant biosynthesis to regulate plant responses during postsubmergence recovery.

Submergence is an abiotic stress that limits agricultural production world-wide. Plants sense oxygen levels during submergence and postsubmergence reoxygenation and modulate their responses. Increasing evidence suggests that completely submerged plants are often exposed to low-light stress, owing to the depth and turbidity of the surrounding water; however, how light availability affects submergence tolerance remains largely unknown. Here, we showed that Arabidopsis thaliana MYB DOMAIN PROTEIN30 (MYB30) is an important transcription factor that integrates light signaling and postsubmergence stress responses. MYB DOMAIN PROTEIN30 protein abundance decreased upon submergence and accumulated during reoxygenation. Under submergence conditions, CONSTITUTIVE PHOTOMORPHOGENIC1 (COP1), a central regulator of light signaling, caused the ubiquitination and degradation of MYB30. In response to desubmergence, however, light-induced MYB30 interacted with MYC2, a master transcription factor involved in jasmonate signaling, and activated the expression of the VITAMIN C DEFECTIVE1 (VTC1) and GLUTATHIONE SYNTHETASE1 (GSH1) gene families to enhance antioxidant biosynthesis. Consistent with this, the myb30 knockout mutant showed increased sensitivity to submergence, which was partially rescued by overexpression of VTC1 or GSH1. Thus, our findings uncover the mechanism by which the COP1-MYB30 module integrates light signals with cellular oxidative homeostasis to coordinate plant responses to postsubmergence stress.

Arabidopsis SINAT Proteins Control Autophagy by Mediating Ubiquitylation and Degradation of ATG13.

In eukaryotes, autophagy maintains cellular homeostasis by recycling cytoplasmic components. The autophagy-related proteins (ATGs) ATG1 and ATG13 form a protein kinase complex that regulates autophagosome formation; however, mechanisms regulating ATG1 and ATG13 remain poorly understood. Here, we show that, under different nutrient conditions, the RING-type E3 ligases SEVEN IN ABSENTIA OF ARABIDOPSIS THALIANA1 (SINAT1), SINAT2, and SINAT6 control ATG1 and ATG13 stability and autophagy dynamics by modulating ATG13 ubiquitylation in Arabidopsis (Arabidopsis thaliana). During prolonged starvation and recovery, ATG1 and ATG13 were degraded through the 26S proteasome pathway. TUMOR NECROSIS FACTOR RECEPTOR ASSOCIATED FACTOR1a (TRAF1a) and TRAF1b interacted in planta with ATG13a and ATG13b and required SINAT1 and SINAT2 to ubiquitylate and degrade ATG13s in vivo. Moreover, lysines K607 and K609 of ATG13a protein contributed to K48-linked ubiquitylation and destabilization, and suppression of autophagy. Under starvation conditions, SINAT6 competitively interacted with ATG13 and induced autophagosome biogenesis. Furthermore, under starvation conditions, ATG1 promoted TRAF1a protein stability in vivo, suggesting feedback regulation of autophagy. Consistent with ATGs functioning in autophagy, the atg1a atg1b atg1c triple knockout mutants exhibited premature leaf senescence, hypersensitivity to nutrient starvation, and reduction in TRAF1a stability. Therefore, these findings demonstrate that SINAT family proteins facilitate ATG13 ubiquitylation and stability and thus regulate autophagy.

SINAT E3 Ubiquitin Ligases Mediate FREE1 and VPS23A Degradation to Modulate Abscisic Acid Signaling.

In plants, the ubiquitin-proteasome system, endosomal sorting, and autophagy are essential for protein degradation; however, their interplay remains poorly understood. Here, we show that four Arabidopsis (Arabidopsis thaliana) E3 ubiquitin ligases, SEVEN IN ABSENTIA OF ARABIDOPSIS THALIANA1 (SINAT1), SINAT2, SINAT3, and SINAT4, regulate the stabilities of FYVE DOMAIN PROTEIN REQUIRED FOR ENDOSOMAL SORTING1 (FREE1) and VACUOLAR PROTEIN SORTING23A (VPS23A), key components of the endosomal sorting complex required for transport-I, to modulate abscisic acid (ABA) signaling. GFP-SINAT1, GFP-SINAT2, and GFP-SINAT4 primarily localized to the endosomal and autophagic vesicles. SINATs controlled FREE1 and VPS23A ubiquitination and proteasomal degradation. SINAT overexpressors showed increased ABA sensitivity, ABA-responsive gene expression, and PYRABACTIN RESISTANCE1-LIKE4 protein levels. Furthermore, the SINAT-FREE1/VPS23A proteins were codegraded by the vacuolar pathway. In particular, during recovery post-ABA exposure, SINATs formed homo- and hetero-oligomers in vivo, which were disrupted by the autophagy machinery. Taken together, our findings reveal a novel mechanism by which the proteasomal and vacuolar turnover systems regulate ABA signaling in plants.

Effects of Umbilical Cord Milking on Anemia in Preterm Infants: A Multicenter Randomized Controlled Trial.

OBJECTIVE: This study aimed to investigate whether umbilical cord milking (UCM) prevents and controls anemia in preterm infants, as compared with immediate cord clamping (ICC). STUDY DESIGN: Pregnant women delivering at <34 weeks' gestation in four hospitals were randomly assigned to undergo UCM or ICC from July 2017 to June 2019. Hematological parameters and iron status were collected and analyzed as primary outcomes at 24 hours, 1 week, 2 weeks, and 6 months after delivery. RESULTS: Neonates receiving UCM had significant higher levels of hemoglobin (Hb), hematocrit, and serum iron (p < 0.05). Lower prevalence of anemia and lower need for transfusions were noted in UCM group. Although UCM was associated with prolonged duration of phototherapy, the maximum levels of bilirubin were similar between two groups (p > 0.05). CONCLUSION: UCM is an effective intervention to help preterm infants experience less anemia with the potential to increase blood volume, as seen by higher Hb levels and more enhanced iron stores.

Brassinosteroids Antagonize Jasmonate-Activated Plant Defense Responses through BRI1-EMS-SUPPRESSOR1 (BES1).

Brassinosteroids (BRs) and jasmonates (JAs) regulate plant growth, development, and defense responses, but how these phytohormones mediate the growth-defense tradeoff is unclear. Here, we identified the Arabidopsis (Arabidopsis thaliana) dwarf at early stages1 (dwe1) mutant, which exhibits enhanced expression of defensin genes PLANT DEFENSIN1.2a (PDF1.2a) and PDF1.2b The dwe1 mutant showed increased resistance to herbivory by beet armyworms (Spodoptera exigua) and infection by botrytis (Botrytis cinerea). DWE1 encodes ROTUNDIFOLIA3, a cytochrome P450 protein essential for BR biosynthesis. The JA-inducible transcription of PDF1.2a and PDF1.2b was significantly reduced in the BRASSINOSTEROID INSENSITIVE1-ETHYL METHANESULFONATE-SUPPRESSOR1 (BES1) gain-of-function mutant bes1- D, which was highly susceptible to S. exigua and B. cinerea BES1 directly targeted the terminator regions of PDF1.2a/PDF1.2b and suppressed their expression. PDF1.2a overexpression diminished the enhanced susceptibility of bes1- D to B. cinerea but did not improve resistance of bes1- D to S. exigua In response to S. exigua herbivory, BES1 inhibited biosynthesis of the JA-induced insect defense-related metabolite indolic glucosinolate by interacting with transcription factors MYB DOMAIN PROTEIN34 (MYB34), MYB51, and MYB122 and suppressing expression of genes encoding CYTOCHROME P450 FAMILY79 SUBFAMILY B POLYPEPTIDE3 (CYP79B3) and UDP-GLUCOSYL TRANSFERASE 74B1 (UGT74B1). Thus, BR contributes to the growth-defense tradeoff by suppressing expression of defensin and glucosinolate biosynthesis genes.

miR-381-3p suppresses breast cancer progression by inhibition of epithelial-mesenchymal transition.

BACKGROUND: Accumulating evidence indicates that miRNAs are involved in multiple cellular functions and participate in various cancer development and progression, including breast cancer. METHODS: We aimed to investigate the role of miR-381-3p in breast cancer. The expression level of miR-381-3p and EMT transcription factors was examined by quantitative real-time PCR (qRT-PCR). The effects of miR-381-3p on breast cancer proliferation and invasion were determined by Cell Counting Kit-8 (CCK-8), colony formation, and transwell assays. The regulation of miR-381-3p on its targets was determined by dual-luciferase analysis, qRT-PCR, and western blot. RESULTS: We found that the expression of miR-381-3p was significantly decreased in breast cancer tissues and cell lines. Overexpression of miR-381-3p inhibited breast cancer proliferation and invasion, whereas knockdown of miR-381-3p promoted cell proliferation and invasion in MDA-MB-231 and SKBR3 cells. Mechanistically, overexpression of miR-381-3p inhibited breast cancer epithelial-mesenchymal transition (EMT). Both Sox4 and Twist1 were confirmed as targets of miR-381-3p. Moreover, transforming growth factor-ß (TGF-ß) could reverse the effects of miR-381-3p on breast cancer progression. CONCLUSIONS: Our observation suggests that miR-381-3p inhibits breast cancer progression and EMT by regulating the TGF-ß signaling via targeting Sox4 and Twist1.

TRAF Family Proteins Regulate Autophagy Dynamics by Modulating AUTOPHAGY PROTEIN6 Stability in Arabidopsis.

Eukaryotic cells use autophagy to recycle cellular components. During autophagy, autophagosomes deliver cytoplasmic contents to the vacuole or lysosome for breakdown. Mammalian cells regulate the dynamics of autophagy via ubiquitin-mediated proteolysis of autophagy proteins. Here, we show that the Arabidopsis thaliana Tumor necrosis factor Receptor-Associated Factor (TRAF) family proteins TRAF1a and TRAF1b (previously named MUSE14 and MUSE13, respectively) help regulate autophagy via ubiquitination. Upon starvation, cytoplasmic TRAF1a and TRAF1b translocated to autophagosomes. Knockout traf1a/b lines showed reduced tolerance to nutrient deficiency, increased salicylic acid and reactive oxygen species levels, and constitutive cell death in rosettes, resembling the phenotypes of autophagy-defective mutants. Starvation-activated autophagosome accumulation decreased in traf1a/b root cells, indicating that TRAF1a and TRAF1b function redundantly in regulating autophagosome formation. TRAF1a and TRAF1b interacted in planta with ATG6 and the RING finger E3 ligases SINAT1, SINAT2, and SINAT6 (with a truncated RING-finger domain). SINAT1 and SINAT2 require the presence of TRAF1a and TRAF1b to ubiquitinate and destabilize AUTOPHAGY PROTEIN6 (ATG6) in vivo. Conversely, starvation-induced SINAT6 reduced SINAT1- and SINAT2-mediated ubiquitination and degradation of ATG6. Consistently, SINAT1/SINAT2 and SINAT6 knockout mutants exhibited increased tolerance and sensitivity, respectively, to nutrient starvation. Therefore, TRAF1a and TRAF1b function as molecular adaptors that help regulate autophagy by modulating ATG6 stability in Arabidopsis.

The Anaerobic Product Ethanol Promotes Autophagy-Dependent Submergence Tolerance in Arabidopsis.

In response to hypoxia under submergence, plants switch from aerobic respiration to anaerobic fermentation, which leads to the accumulation of the end product, ethanol. We previously reported that Arabidopsis thaliana autophagy-deficient mutants show increased sensitivity to ethanol treatment, indicating that ethanol is likely involved in regulating the autophagy-mediated hypoxia response. Here, using a transcriptomic analysis, we identified 3909 genes in Arabidopsis seedlings that were differentially expressed in response to ethanol treatment, including 2487 upregulated and 1422 downregulated genes. Ethanol treatment significantly upregulated genes involved in autophagy and the detoxification of reactive oxygen species. Using transgenic lines expressing AUTOPHAGY-RELATED PROTEIN 8e fused to green fluorescent protein (GFP-ATG8e), we confirmed that exogenous ethanol treatment promotes autophagosome formation in vivo. Phenotypic analysis showed that deletions in the alcohol dehydrogenase gene in adh1 mutants result in attenuated submergence tolerance, decreased accumulation of ATG proteins, and diminished submergence-induced autophagosome formation. Compared to the submergence-tolerant Arabidopsis accession Columbia (Col-0), the submergence-intolerant accession Landsberg erecta (Ler) displayed hypersensitivity to ethanol treatment; we linked these phenotypes to differences in the functions of ADH1 and the autophagy machinery between these accessions. Thus, ethanol promotes autophagy-mediated submergence tolerance in Arabidopsis.

Polyunsaturated linolenoyl-CoA modulates ERF-VII-mediated hypoxia signaling in Arabidopsis.

In plants, submergence from flooding causes hypoxia, which impairs energy production and affects plant growth, productivity, and survival. In Arabidopsis, hypoxia induces nuclear localization of the group VII ethylene-responsive transcription factor RELATED TO AP2.12 (RAP2.12), following its dissociation from the plasma membrane-anchored ACYL-COA BINDING PROTEIN1 (ACBP1) and ACBP2. Here, we show that polyunsaturated linolenoyl-CoA (18:3-CoA) regulates RAP2.12 release from the plasma membrane. Submergence caused a significant increase in 18:3-CoA, but a significant decrease in 18:0-, 18:1-, and 18:2-CoA. Application of 18:3-CoA promoted nuclear accumulation of the green fluorescent protein (GFP) fusions RAP2.12-GFP, HYPOXIA-RESPONSIVE ERF1-GFP, and RAP2.3-GFP, and enhanced transcript levels of hypoxia-responsive genes. Plants with decreased ACBP1 and ACBP2 (acbp1 ACBP2-RNAi, produced by ACBP2 RNA interference in the acbp1 mutant) had reduced tolerance to hypoxia and impaired 18:3-CoA-induced expression of hypoxia-related genes. In knockout mutants and overexpression lines of LONG-CHAIN ACYL-COA SYNTHASE2 (LACS2) and FATTY ACID DESATURASE 3 (FAD3), the acyl-CoA pool size and 18:3-CoA levels were closely related to ERF-VII-mediated signaling and hypoxia tolerance. These findings demonstrate that polyunsaturation of long-chain acyl-CoAs functions as important mechanism in the regulation of plant hypoxia signaling, by modulating ACBP-ERF-VII dynamics.

Natural variation in the promoter of rice calcineurin B-like protein10 (OsCBL10) affects flooding tolerance during seed germination among rice subspecies.

Rice (Oryza sativa L.) has two ecotypes, upland and lowland rice, that have been observed to show different tolerance levels under flooding stress. In this study, two rice cultivars, upland (Up221, flooding-intolerant) and lowland (Low88, flooding-tolerant), were initially used to study their molecular mechanisms in response to flooding germination. We observed that variations in the OsCBL10 promoter sequences in these two cultivars might contribute to this divergence in flooding tolerance. Further analysis using another eight rice cultivars revealed that the OsCBL10 promoter could be classified as either a flooding-tolerant type (T-type) or a flooding-intolerant type (I-type). The OsCBL10 T-type promoter only existed in japonica lowland cultivars, whereas the OsCBL10 I-type promoter existed in japonica upland, indica upland and indica lowland cultivars. Flooding-tolerant rice cultivars containing the OsCBL10 T-type promoter have shown lower Ca2+ flow and higher α-amylase activities in comparison to those in flooding-intolerant cultivars. Furthermore, the OsCBL10 overexpression lines were sensitive to both flooding and hypoxic treatments during rice germination with enhanced Ca2+ flow in comparison to wild-type. Subsequent findings also indicate that OsCBL10 may affect OsCIPK15 protein abundance and its downstream pathways. In summary, our results suggest that the adaptation to flooding stress during rice germination is associated with two different OsCBL10 promoters, which in turn affect OsCBL10 expression in different cultivars and negatively affect OsCIPK15 protein accumulation and its downstream cascade.

Alternative splicing and translation play important roles in hypoxic germination in rice.

Post-transcriptional mechanisms (PTMs), including alternative splicing (AS) and alternative translation initiation (ATI), may explain the diversity of proteins involved in plant development and stress responses. Transcriptional regulation is important during the hypoxic germination of rice seeds, but the potential roles of PTMs in this process have not been characterized. We used a combination of proteomics and RNA sequencing to discover how AS and ATI contribute to plant responses to hypoxia. In total, 10 253 intron-containing genes were identified. Of these, ~1741 differentially expressed AS (DAS) events from 811 genes were identified in hypoxia-treated seeds compared with controls. Over 95% of these were not present in the list of differentially expressed genes. In particular, regulatory pathways such as the spliceosome, ribosome, endoplasmic reticulum protein processing and export, proteasome, phagosome, oxidative phosphorylation, and mRNA surveillance showed substantial AS changes under hypoxia, suggesting that AS responses are largely independent of transcriptional regulation. Considerable AS changes were identified, including the preferential usage of some non-conventional splice sites and enrichment of splicing factors in the DAS data sets. Taken together, these results not only demonstrate that AS and ATI function during hypoxic germination but they have also allowed the identification of numerous novel proteins/peptides produced via ATI.

Jasmonate Regulates Plant Responses to Postsubmergence Reoxygenation through Transcriptional Activation of Antioxidant Synthesis.

Submergence induces hypoxia in plants; exposure to oxygen following submergence, termed reoxygenation, produces a burst of reactive oxygen species. The mechanisms of hypoxia sensing and signaling in plants have been well studied, but how plants respond to reoxygenation remains unclear. Here, we show that reoxygenation in Arabidopsis (Arabidopsis thaliana) involves rapid accumulation of jasmonates (JAs) and increased transcript levels of JA biosynthesis genes. Application of exogenous methyl jasmonate improved tolerance to reoxygenation in wild-type Arabidopsis; also, mutants deficient in JA biosynthesis and signaling were very sensitive to reoxygenation. Moreover, overexpression of the transcription factor gene MYC2 enhanced tolerance to posthypoxic stress, and myc2 knockout mutants showed increased sensitivity to reoxygenation, indicating that MYC2 functions as a key regulator in the JA-mediated reoxygenation response. MYC2 transcriptionally activates members of the VITAMIN C DEFECTIVE (VTC) and GLUTATHIONE SYNTHETASE (GSH) gene families, which encode rate-limiting enzymes in the ascorbate and glutathione synthesis pathways. Overexpression of VTC1 and GSH1 in the myc2-2 mutant suppressed the posthypoxic hypersensitive phenotype. The JA-inducible accumulation of antioxidants may alleviate oxidative damage caused by reoxygenation, improving plant survival after submergence. Taken together, our findings demonstrate that JA signaling interacts with the antioxidant pathway to regulate reoxygenation responses in Arabidopsis.

Flattening axial intensity oscillations of a diffracted Bessel beam through a cardioid-like hole.

We present a new feasible way to flatten the axial intensity oscillations for diffraction of a finite-sized Bessel beam, through designing a cardioid-like hole. The boundary formula of the cardioid-like hole is given analytically. Numerical results by the complete Rayleigh-Sommerfeld method reveal that the Bessel beam propagates stably in a considerably long axial range, after passing through the cardioid-like hole. Compared with the gradually absorbing apodization technique in previous papers, in this paper a hard truncation of the incident Bessel beam is employed at the cardioid-like hole edges. The proposed hard apodization technique takes two advantages in suppressing the axial intensity oscillations, i.e., easier implementation and higher accuracy. It is expected to have practical applications in laser machining, light sectioning, or optical trapping.

Unsaturation of very-long-chain ceramides protects plant from hypoxia-induced damages by modulating ethylene signaling in Arabidopsis.

Lipid remodeling is crucial for hypoxic tolerance in animals, whilst little is known about the hypoxia-induced lipid dynamics in plants. Here we performed a mass spectrometry-based analysis to survey the lipid profiles of Arabidopsis rosettes under various hypoxic conditions. We observed that hypoxia caused a significant increase in total amounts of phosphatidylserine, phosphatidic acid and oxidized lipids, but a decrease in phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Particularly, significant gains in the polyunsaturated species of PC, PE and phosphatidylinositol, and losses in their saturated and mono-unsaturated species were evident during hypoxia. Moreover, hypoxia led to a remarkable elevation of ceramides and hydroxyceramides. Disruption of ceramide synthases LOH1, LOH2 and LOH3 enhanced plant sensitivity to dark submergence, but displayed more resistance to submergence under light than wild type. Consistently, levels of unsaturated very-long-chain (VLC) ceramide species (22:1, 24:1 and 26:1) predominantly declined in the loh1, loh2 and loh3 mutants under dark submergence. In contrast, significant reduction of VLC ceramides in the loh1-1 loh3-1 knockdown double mutant and lacking of VLC unsaturated ceramides in the ads2 mutants impaired plant tolerance to both dark and light submergences. Evidence that C24:1-ceramide interacted with recombinant CTR1 protein and inhibited its kinase activity in vitro, enhanced ER-to-nucleus translocation of EIN2-GFP and stabilization of EIN3-GFP in vivo, suggests a role of ceramides in modulating CTR1-mediated ethylene signaling. The dark submergence-sensitive phenotypes of loh mutants were rescued by a ctr1-1 mutation. Thus, our findings demonstrate that unsaturation of VLC ceramides is a protective strategy for hypoxic tolerance in Arabidopsis.

[Early rehabilitation intervention reduces the incidence of extrauterine growth retardation in preterm infants].

OBJECTIVE: To investigate the effect of early rehabilitation intervention on the incidences of extrauterine growth retardation (EUGR) and early diseases in preterm infants. METHODS: The appropriate-for-gestational-age preterm infants with a gestational age of <34 weeks and a birth weight of 1 000 to <2 000 g who were admitted to the neonatal intensive care unit (NICU) within 24 hours after birth were enrolled in a prospective randomized controlled trial. These infants were randomly divided into rehabilitation intervention group and control group. The infants in the rehabilitation intervention group were given early rehabilitation after their vital signs became stable, including oral sensory and muscle strength training and pressure touching of the head, chest, abdomen, extremities, hands, and feet. The primary outcome measures were the time to independent oral feeding, length of hospital stay, and incidence rate of EUGR. The secondary outcome measures were the incidence rates of related diseases in preterm infants, such as apnea, feeding intolerance, and sepsis. RESULTS: A total of 97 preterm infants who met the inclusion criteria and had complete data were enrolled, with 48 in the control group and 49 in the rehabilitation intervention group. The rehabilitation intervention group had a shorter time to independent oral feeding than the control group (P<0.05). Compared with the control group, the rehabilitation intervention group had a shorter length of hospital stay and a lower corrected gestational age at discharge (P<0.05), as well as a lower incidence rate of EUGR (P<0.05). The rehabilitation intervention group ONCLUSIONS: Early rehabilitation intervention for preterm infants in the NICU may reduce the incidence rates of apnea, feeding intolerance, and EUGR and help them to achieve independent oral feeding early.

Arabidopsis acyl-CoA-binding protein ACBP3 participates in plant response to hypoxia by modulating very-long-chain fatty acid metabolism.

In Arabidopsis thaliana, acyl-CoA-binding proteins (ACBPs) are encoded by a family of six genes (ACBP1 to ACBP6), and are essential for diverse cellular activities. Recent investigations suggest that the membrane-anchored ACBPs are involved in oxygen sensing by sequestration of group VII ethylene-responsive factors under normoxia. Here, we demonstrate the involvement of Arabidopsis ACBP3 in hypoxic tolerance. ACBP3 transcription was remarkably induced following submergence under both dark (DS) and light (LS) conditions. ACBP3-overexpressors (ACBP3-OEs) showed hypersensitivity to DS, LS and ethanolic stresses, with reduced transcription of hypoxia-responsive genes as well as accumulation of hydrogen peroxide in the rosettes. In contrast, suppression of ACBP3 in ACBP3-KOs enhanced plant tolerance to DS, LS and ethanol treatments. By analyses of double combinations of OE-1 with npr1-5, coi1-2, ein3-1 as well as ctr1-1 mutants, we observed that the attenuated hypoxic tolerance in ACBP3-OEs was dependent on NPR1- and CTR1-mediated signaling pathways. Lipid profiling revealed that both the total amounts and very-long-chain species of phosphatidylserine (C42:2- and C42:3-PS) and glucosylinositolphosphorylceramides (C22:0-, C22:1-, C24:0-, C24:1-, and C26:1-GIPC) were significantly lower in ACBP3-OEs but increased in ACBP3-KOs upon LS exposure. By microscale thermophoresis analysis, the recombinant ACBP3 protein bound VLC acyl-CoA esters with high affinities in vitro. Further, a knockout mutant of MYB30, a master regulator of very-long-chain fatty acid (VLCFA) biosynthesis, exhibited enhanced sensitivities to LS and ethanolic stresses, phenotypes that were ameliorated by ACBP3-RNAi. Taken together, these findings suggest that Arabidopsis ACBP3 participates in plant response to hypoxia by modulating VLCFA metabolism.

[Risk factors for extrauterine growth restriction in preterm infants with gestational age less than 34 weeks].

OBJECTIVE: To investigate the correlated factors contributed to extrauterine growth restriction (EUGR) in preterm infants with the gestational age less than 34 weeks. METHODS: A total of 694 preterm infants with the gestational ages less than 34 weeks were enrolled. They were classified into EUGR and non-EUGR groups by weight on discharge. The perinatal data, growth data, nutritional information and morbidities during hospitalization were compared between the two groups. RESULTS: EUGR on discharge occurred in 284 (40.9%) out of the 694 infants. The incidence of EUGR in intrauterine growth restriction (IUGR) infants was significantly higher than in non-IUGR infants (P<0.01). The very low birth weight (VLBW) infants had a higher incidence of EUGR than non-VLBW infants (P<0.01). The incidence of EUGR increased with the decreases of gestational age at birth and birth weight (P<0.01). Compared with the non-EUGR group, the fasting time, the duration of parenteral nutrition, the time beginning to feed and the age to achieve full enteral feeds were significantly greater in the EUGR group (P<0.01). The cumulative protein deficit and cumulative caloric deficit in the first week of life in the EUGR group were higher than in the non-EUGR group (P<0.05). The incidences of respiratory distress syndrome, apnea, necrotizing enterocolitis and septicemia in the EUGR group were higher than in the non-EUGR group (P<0.05). The logistic regression analysis showed that birth weight, gestational age at birth and IUGR were the independent risk factors for EUGR. CONCLUSIONS: The incidence of EUGR in infants with gestational age less than 34 weeks is high, especially in IUGR or VLBW infants. Early and aggressive nutritional strategy and prevention of apnea and septicemia may facilitate to reduce the occurrence of EUGR.

[Pseudo-furocoumarin: synthesis, DNA-binding behavior and cytotoxicity].

Furocoumarin shows some antitumor activity when it is radiated by the UV light. In order to improve the antitumor activity of furocoumarin under standard environment conditions, the "minimal DNA-intercalating" hypothesis was firstly introduced to the structural modification of furocoumarin, which resulted in the design of pseudo-furocoumarin. The pseudo-furocoumarin was synthesized by two-step reaction including Pechmann reaction catalyzed by conc. H2SO4 and Suzuki coupling reaction catalyzed by Pd(PPh3)4. The structural character of the pseudo-furocoumarin is that the bonding mode of furan ring fused to the coumarin is replaced by a chemical single bond between furan ring and coumarin. The interaction of the pseudo-furocoumarin with calf thymus DNA (CT-DNA) has been respectively investigated by using DNA melting curve, UV-Vis absorption spectra, fluorescence spectra and viscosity titration, and the modes of DNA-binding for the pseudo-furocoumarin have been proposed. Based on the results of DNA melting curve, spectra and viscosity titration, it was suggested that 5a and 5b bind to DNA by the partial intercalation and classical intercalation, respectively. The DNA-binding behaviors of 5c and 5d have been rarely reported in literature and may be interpreted in terms of bridge-structure. All target compounds, except 5b, show a decreasing capability of intercalation to DNA. Further, the antiproliferative activities of the pseudo-furocoumarin on human lung adenocarcinoma (A549), human breast cancer (MCF-7) and human ovarian carcinoma cell line (SKOV-3) in vitro were evaluated using the sulforhodamine B (SRB) protein statin assay. All pseudo-furocoumarin exhibited an improved anti-proliferative activity as compared with the control compound psoralen (PS, a linear furocoumarin). Interestingly the pseudo-furocoumarin binding to DNA by a non-classical intercalation mode showed a stronger anti-proliferative activity than PS. The present study extended the applied areas of "minimal DNA-intercalating" hypothesis, and provided a method for the structural modification of furocoumarin as well.