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1.
Plant Mol Biol ; 112(6): 341-356, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37523053

RESUMEN

Cuticular wax, cutin and suberin polyesters covering the surface of some fleshy fruit are tightly associated with skin color and appearance. ß-Ketoacyl-CoA synthase (KCS) is a rate-limiting enzyme participating in the synthesis of very-long-chain fatty acids (VLCFAs), the essential precursors of cuticular waxes and aliphatic monomers of suberin. However, information on the KCS gene family in pear genome and the specific members involved in pear fruit skin formation remain unclear. In the present study, we performed an investigation of the composition and amount of cuticular waxes, cutin and aliphatic suberin in skins of four sand pear varieties with distinct colors (russet, semi-russet, and green) and demonstrated that the metabolic shifts of cuticular waxes and suberin leading to the significant differences of sand pear skin color. A genome-wide identification of KCS genes from the pear genome was conducted and 35 KCS coding genes were characterized and analyzed. Expression profile analysis revealed that the KCS genes had diverse expression patterns among different pear skins and the transcript abundance of PbrKCS15, PbrKCS19, PbrKCS24, and PbrKCS28 were consistent with the accumulation of cuticular waxes and suberin in fruit skin respectively. Subcellular localization analysis demonstrated that PbrKCS15, PbrKCS19, PbrKCS24 and PbrKCS28 located on the endoplasmic reticulum (ER). Further, transient over-expression of PbrKCS15, PbrKCS19, and PbrKCS24 in pear fruit skins significantly increased cuticular wax accumulation, whereas PbrKCS28 notably induced suberin deposition. In conclusion, pear fruit skin color and appearance are controlled in a coordinated way by the deposition of the cuticular waxes and suberin. PbrKCS15, PbrKCS19, and PbrKCS24 are involved in cuticular wax biosynthesis, and PbrKCS28 is involved in suberin biosynthesis, which play essential roles in pear fruit skin formation. Moreover, this work provides a foundation for further understanding the functions of KCS genes in pear.


Asunto(s)
Pyrus , Pyrus/genética , Pyrus/metabolismo , Frutas/genética , Frutas/metabolismo , Ceras/metabolismo , Regulación de la Expresión Génica de las Plantas
2.
Genes (Basel) ; 14(4)2023 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-37107575

RESUMEN

Boron (B) deficiency stress is frequently observed in pear orchards and causes a considerable loss of productivity and fruit quality. Pyrus betulaefolia is one of the most important rootstocks that has been widely used in pear production. The present study confirmed that the boron form of different tissues showed various changes, and the free boron content was significantly decreased under the short-term B deficiency condition. Moreover, the ABA and JA content also significantly accumulated in the root after short-term B deficiency treatment. A comprehensive transcriptome analysis of 24 h B deficiency treatment P. betulaefolia root was performed in this study. Transcriptome results revealed a total of 1230 up-regulated and 642 down-regulated differentially expressed genes (DEGs), respectively. B deficiency significantly increased the expression of the key aquaporin gene NIP5-1. In addition, B deficiency also increased the expression of ABA (ZEP and NCED) and JA (LOX, AOS and OPR) synthesis genes. Several MYB, WRKY, bHLH and ERF transcription factors were induced by B deficiency stress, which may relate to the regulation of B uptake and plant hormone synthesis. Overall, these findings suggested that P. betulaefolia root had adaptive responses to short-term B deficiency stress by improved boron absorption ability and hormone (JA and ABA) synthesis. The transcriptome analysis provided further information for understanding the mechanism of the pear rootstock responses to B deficiency stress.


Asunto(s)
Pyrus , Pyrus/genética , Boro , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilación de la Expresión Génica , Transcriptoma
3.
Planta ; 257(4): 69, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36854938

RESUMEN

MAIN CONCLUSION: PpyMYB144 directly activates the promoter of PpyCYP86B1, promotes the synthesis of α, ω-diacids, and involves in pear fruit skin russeting. Russeting is an economically important surface disorder in pear (Pyrus pyrifolia) fruit. Previous research has demonstrated that suberin is the pivotal chemical component contributing to pear fruit skin russeting, and fruit bagging treatment effectively reduces the amount of suberin of fruits, and thereby reduces the russeting phenotype. However, the mechanisms of pear fruit skin russeting remain largely unclear, particularly the transcriptional regulation. Here, we dissected suberin concentration and composition of pear fruits along fruit development and confirmed that α, ω-diacids are the predominant constituents in russeted pear fruit skins. Two cytochrome P450 monooxygenase (CYP) family genes (PpyCYP86A1 and PpyCYP86B1) and nine MYB genes were isolated from pear fruit. Expressions of PpyCYP86A1, PpyCYP86B1, and five MYB genes (PpyMYB34, PpyMYB138, PpyMYB138-like, PpyMYB139, and PpyMYB144) were up-regulated during fruit russeting and showed significant correlations with the changes of α, ω-diacids. In addition, dual-luciferase assays indicated that PpyMYB144 could trans-activate the promoter of PpyCYP86B1, and the activation was abolished by motif mutagenesis of AC element on the PpyCYP86B1 promoter. Further, Agrobacterium-mediated transient expression of PpyCYP86B1 and PpyMYB144 in pear fruits induced the deposition of aliphatic suberin. Thus, PpyMYB144 is a novel direct activator of PpyCYP86B1 and contributes to pear fruit skin russeting.


Asunto(s)
Pyrus , Pyrus/genética , Frutas/genética , Metabolismo Secundario , Sistema Enzimático del Citocromo P-450/genética , Agrobacterium
4.
Mol Biol Rep ; 49(12): 12055-12061, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36309610

RESUMEN

BACKGROUND: Watercore is a common physiological disorder in pear and is closely related to the excessive accumulation of sorbitol and sucrose. Our previous research found that the incidence of watercore in 'Akibae' (Pyrus pyrifolia cv. Akibae) fruit significantly decreased after boron application (BA). Moreover, the foliar spray of boric acid also significantly improved fruit quality. However, the mechanisms underlying the pear fruit response to BA was still limited. METHODS AND RESULTS: A comprehensive transcriptome analysis of BA treatment 'Akibae' pear fruit was performed in this study. Transcriptome results revealed a total of 3146 up-regulated and 1145 down-regulated differentially expressed genes (DEGs) between control and treated fruits of 'Akibae' pear. BA significantly induced the expression of sorbitol metabolism and sucrose metabolism genes. In addition, BA also increased the expression of starch degradation, fatty acid synthesis, IAA (indole-3-acetic acid) degradation, and GA (gibberellin acid) synthesis genes and inhibited the expression of ethylene synthesis genes. CONCLUSIONS: These findings suggested that BA probably alleviates 'Akibae' watercore occurrence and improves fruit quality by regulating the decrease in sorbitol and sucrose, the increase in fatty acids and the balance of plant hormones. Our results provide further information for understanding the molecular mechanism of the effect of BA on pear fruit.


Asunto(s)
Pyrus , Pyrus/genética , Pyrus/metabolismo , Frutas/genética , Frutas/metabolismo , Transcriptoma/genética , Boro/farmacología , Boro/metabolismo , Regulación de la Expresión Génica de las Plantas , Perfilación de la Expresión Génica , Sacarosa/farmacología , Sacarosa/metabolismo , Sorbitol
5.
Infect Drug Resist ; 15: 3205-3211, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35754784

RESUMEN

Objective: The present study aims to explore the effects of different numbers of fiberoptic bronchoscopic examinations on the nosocomial infection/colonization of carbapenem-resistant Enterobacteriaceae (CRE). Methods: The data of 129 patients admitted to the intensive care unit of a grade 3A hospital were retrospectively analyzed, and CRE nosocomial infection/colonization situations in patients with fiberoptic bronchoscope application times of 1, 2, 3, and ≥4 were statistically analyzed. Results: The incidence of nosocomial infection/colonization of CRE increased significantly when the number of fiberoptic bronchoscopic examinations was ≥3. Conclusion: Nosocomial infection/colonization of CRE is highly correlated with an increased number of fiberoptic bronchoscopic examinations.

6.
Genes (Basel) ; 13(6)2022 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-35741739

RESUMEN

Watercore is a physiological disorder which often occurs on the pear fruit and the excessive accumulation of sorbitol in fruit intercellular space is considered to be an important cause of watercore. Our previous studies found that the metabolic disorder of sugars may lead to hypoxia stress and disturb respiration, resulting in aggravated fruit rot and the formation of bitter substances. However, the further changes of respiration and the fruit response mechanism are not well understood. A comprehensive transcriptome analysis of 'Akibae' pear watercore fruit was performed in this study. The transcriptome results revealed the hypoxia stress significantly induced the expression of several key enzymes in the TCA cycle and may lead to the accumulation of succinic acid in watercore fruit. The glycolytic pathway was also significantly enhanced in watercore fruit. Moreover, the γ-aminobutyric acid (GABA) synthesis related genes, glutamate decarboxylase (GAD) genes and polyamine oxidase (PAO) genes, which associated with the GABA shunt and the polyamine degradation pathway were significantly upregulated. In addition, the PpGAD1 transcript level increased significantly along with the increase of GAD activity and GABA content in the watercore fruit. Above all, these findings suggested that the hypoxic response was marked by a significant increase of the hypoxia-inducible metabolites succinic acid and GABA and that PpGAD1 may play a key role in response to watercore by controlling the GABA synthesis.


Asunto(s)
Pyrus , Frutas/genética , Frutas/metabolismo , Hipoxia/genética , Respiración , Ácido Succínico , Ácido gamma-Aminobutírico/genética
7.
Plant Sci ; 317: 111179, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35193736

RESUMEN

Watercore is a physiological disorder which often occurs on the fruits of pear and closely related to the influence of environment factors, such as high temperature. The excessive accumulation of sorbitol in fruit intercellular space is considered to be an important cause of watercore. Sorbitol transporter (SOT) is the key translocation protein of sorbitol and our previous study found the PpSOT3 expression was significantly decreased in high temperature induced-watercore pear fruit by transcriptome method. How PpSOT3 regulates the occurrence of watercore in pear remains unclear. The present study found that PpSOT3 had different expression pattern in watercore-susceptible (Akibae and Hosui) and watercore-resistant (Aikansui) pear cultivars of young fruit and mature fruit. Moreover, the accumulation of intercellular sorbitol in watercore fruit was significantly higher than that in healthy fruit, and the expression of PpSOT3 was significantly inhibited. After the treatment of sugar transport inhibitor (para-chloromercuribenzenesulphonic acid, PCMBS), the fruit pulp occurred water-soaking and the expression of PpSOT3 and the intercellular sorbitol content was significantly decreased and increased, respectively. Subcellular localization showed that PpSOT3 was located in plasma membrane. Both transient overexpression and RNAi assays suggested PpSOT3 had the function of sorbitol uptake. Taken together, these results demonstrate that PpSOT3 was a PCMBS-sensitive sorbitol transporter and played an important role in the occurrence of watercore by modulating the level of intercellular sorbitol content.


Asunto(s)
Pyrus , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Transporte de Membrana/metabolismo , Pyrus/genética , Pyrus/metabolismo , Sorbitol/metabolismo , Transcriptoma
8.
Int J Mol Sci ; 23(4)2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35216299

RESUMEN

Seed dormancy transition is a vital developmental process for seedling propagation and agricultural production. The process is precisely regulated by diverse endogenous genetic factors and environmental cues. Callery pear (Pyrus calleryana Decne) is an important rootstock species that requires cold stratification to break seed dormancy, but the mechanisms underlying pear seed dormancy release are not yet fully understood. Here, we analyzed the transcriptome profiles at three different stages of cold stratification in callery pear seeds using RNA sequencing combined with phytohormone and sugar content measurements. Significant alterations in hormone contents and carbohydrate metabolism were observed and reflected the dormancy status of the seeds. The expressions of genes related to plant hormone metabolism and signaling transduction, including indole-3-acetic acid (IAA) biosynthesis (ASAs, TSA, NITs, YUC, and AAO) genes as well as several abscisic acid (ABA) and gibberellic acid (GA) catabolism and signaling transduction genes (CYP707As, GA2ox, and DELLAs), were consistent with endogenous hormone changes. We further found that several genes involved in cytokinin (CTK), ethylene (ETH), brassionolide (BR), and jasmonic acid (JA) metabolism and signaling transduction were differentially expressed and integrated in pear seed dormancy release. In accordance with changes in starch and soluble sugar contents, the genes associated with starch and sucrose metabolism were significantly up-regulated during seed dormancy release progression. Furthermore, the expression levels of genes involved in lipid metabolism pathways were also up-regulated. Finally, 447 transcription factor (TF) genes (including ERF, bHLH, bZIP, NAC, WRKY, and MYB genes) were observed to be differentially expressed during seed cold stratification and might relate to pear seed dormancy release. Our results suggest that the mechanism underlying pear seed dormancy release is a complex, transcriptionally regulated process involving hormones, sugars, lipids, and TFs.


Asunto(s)
Latencia en las Plantas , Pyrus , Ácido Abscísico/metabolismo , Regulación de la Expresión Génica de las Plantas , Germinación/genética , Hormonas/metabolismo , Latencia en las Plantas/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Pyrus/genética , Pyrus/metabolismo , Semillas/metabolismo , Almidón/metabolismo , Azúcares/metabolismo , Transcriptoma
9.
J Integr Plant Biol ; 63(12): 2123-2135, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34655280

RESUMEN

Pear has an S-RNase-based gametophytic self-incompatibility (SI) system. Nuclear DNA degradation is a typical feature of incompatible pollen tube death, and is among the many physiological functions of vacuoles. However, the specific changes that occur in vacuoles, as well as the associated regulatory mechanism in pear SI, are currently unclear. Although research in tobacco has shown that decreased activity of diacylglycerol kinase (DGK) results in the morphological change of pollen tube vacuole, whether DGK regulates the pollen tube vacuole of tree plants and whether it occurs in SI response, is currently unclear. We found that DGK activity is essential for pear pollen tube growth, and DGK4 regulates pollen tube vacuole morphology following its high expression and deposition at the tip and shank edge of the pollen tube of pear. Specifically, incompatible S-RNase may induce cytoplasmic acidification of the pollen tube by inhibiting V-ATPase V0 domain a1 subunit gene expression as early as 30 min after treatment, when the pollen tube is still alive. Cytoplasmic acidification induced by incompatible S-RNase results in reduced DGK4 abundance and deposition, leading to morphological change of the vacuole and fragmentation of nuclear DNA, which indicates that DGK4 is a key factor in pear SI response.


Asunto(s)
Pyrus , ADN/metabolismo , Diacilglicerol Quinasa/genética , Diacilglicerol Quinasa/metabolismo , Concentración de Iones de Hidrógeno , Tubo Polínico/metabolismo , Pyrus/genética , Pyrus/metabolismo , Vacuolas/metabolismo
10.
Int J Mol Sci ; 22(9)2021 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-34066340

RESUMEN

Watercore is a physiological disorder that commonly occurs in sand pear cultivars. The typical symptom of watercore tissue is transparency, and it is often accompanied by browning, breakdown and a bitter taste during fruit ripening. To better understand the molecular mechanisms of watercore affecting fruit quality, this study performed transcriptome and metabolome analyses on watercore pulp from "Akibae" fruit 125 days after flowering. The present study found that the "Akibae" pear watercore pulp contained higher sorbitol and sucrose than healthy fruit. Moreover, the structure of the cell wall was destroyed, and the content of pectin, cellulose and hemicellulose was significantly decreased. In addition, the content of ethanol and acetaldehyde was significantly increased, and the content of polyphenol was significantly decreased. Watercore induced up-regulated expression levels of sorbitol synthesis-related (sorbitol-6-phosphate dehydrogenase, S6PDH) and sucrose synthesis-related genes (sucrose synthesis, SS), whereas it inhibited the expression of sorbitol decomposition-related genes (sorbitol dehydrogenase, SDH) and sorbitol transport genes (sorbitol transporter, SOT). Watercore also strongly induced increased expression levels of cell wall-degrading enzymes (polygalactosidase, PG; ellulase, CX; pectin methylesterase, PME), as well as ethanol synthesis-related (alcohol dehydrogenase, ADH), acetaldehyde synthesis-related (pyruvate decarboxylase, PDC) and polyphenol decomposition-related genes (polyphenol oxidase, PPO). Moreover, the genes that are involved in ethylene (1-aminocyclopropane- 1-carboxylate oxidase, ACO; 1-aminocyclopropane- 1-carboxylate synthase, ACS) and abscisic acid (short-chain alcohol dehydrogenase, SDR; aldehyde oxidase, AAO) synthesis were significantly up-regulated. In addition, the bitter tasting amino acids, alkaloids and polyphenols were significantly increased in watercore tissue. Above all, these findings suggested that the metabolic disorder of sorbitol and sucrose can lead to an increase in plant hormones (abscisic acid and ethylene) and anaerobic respiration, resulting in aggravated fruit rot and the formation of bitter substances.


Asunto(s)
Frutas/genética , Frutas/metabolismo , Metaboloma/genética , Enfermedades de las Plantas/genética , Pyrus/genética , Pyrus/metabolismo , Transcriptoma/genética , Ácido Abscísico/metabolismo , Acetaldehído/análisis , Pared Celular/metabolismo , Pared Celular/ultraestructura , Etanol/análisis , Etilenos/metabolismo , Frutas/ultraestructura , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Ontología de Genes , Modelos Biológicos , Fenoles/análisis , Pyrus/ultraestructura , Análisis de Secuencia de ARN , Gusto
11.
Phys Chem Chem Phys ; 23(10): 6154-6161, 2021 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-33686385

RESUMEN

Exploring the manipulation of magnetism in perovskite oxides is scientifically interesting and of great technical importance in next-generation magnetic memory. Dual control of magnetism in superlattices through epitaxial strain and ferroelectric polarization may induce rich physical properties. In this work, we demonstrated a strong magnetoelectric coupling that appears in an La0.75Sr0.25MnO3/BaTiO3 superlattice. Reversible transitions in ferromagnetism, ferrimagnetism and anti-ferromagnetism, with strong magnetoelectric coupling, are achieved by precisely controlling the magnitude and spin-direction of the magnetic moments of Mn. Half-metallicity is demonstrated in the MnO2 layers, accompanied by the spin polarization of the superlattice varying from 100% to 0%. We realize the coexistence of ferroelectric polarization and metallicity, i.e., "ferroelectric metal". The variation in strain and re-orientation of polarization lead to a change in interfacial Ti-O and Mn-O bond lengths, and hence a hybridization state, determining the magnetism of our system. The purpose-designed LSMO/BTO superlattice with intrinsic magnetoelectric coupling is a particularly interesting model system that can provide guidance for the development of spintronic devices.

12.
Tree Physiol ; 41(7): 1306-1318, 2021 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-33367887

RESUMEN

Fruit semi-russeting is an undesirable quality trait that occurs in fruit production. It is reported that preharvest fruit bagging could effectively alleviate fruit exocarp semi-russeting, but the physiological and molecular mechanisms remain unclear. In the present study, we performed an in-depth investigation into pear fruit semi-russeting from morphologic, metabolic and transcriptomic perspectives by comparing control (semi-russeted) and bagged (non-russeted) 'Cuiguan' pear fruits. The results showed that significant changes in cutin and suberin resulted in pear fruit semi-russeting. Compared with the skin of bagged fruits, the skin of the control fruits presented reduced cutin contents accompanied by an accumulation of suberin, which resulted in fruit semi-russeting; α, ω-dicarboxylic acids accounted for the largest proportion of typical suberin monomers. Moreover, combined transcriptomic and metabolic analysis revealed a series of genes involved in cutin and suberin biosynthesis, transport and polymerization differentially expressed between the two groups. Furthermore, the expression levels of genes involved in the stress response and in hormone biosynthesis and signaling were significantly altered in fruits with contrasting phenotypes. Finally, a number of transcription factors, including those of the MYB, NAC, bHLH and bZIP families, were differentially expressed. Taken together, the results suggest that the multilayered mechanism through which bagging alleviates pear fruit semi-russeting is complex, and the large number of candidate genes identified provides a good foundation for future functional studies.


Asunto(s)
Pyrus , Frutas/genética , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Fenotipo , Pyrus/genética , Transcriptoma
13.
RSC Adv ; 10(43): 25480-25486, 2020 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-35518619

RESUMEN

Large scale cesium lead-halide (CsPbX3, X = Cl, Br, and I) perovskite films have become the basis of laser applications. Common fabrication methods such as spin-coating and thermal evaporation have a trade-off between high quality and low cost. Herein, we reported a facile method for preparing a large area homogeneous perovskite CsPbBr3 film via a multiple centrifugal deposition and solvent annealing (MCDSA) method. This method is superior because it can control the thickness (180 nm to 880 nm) of the film, ensure the film is crack and pinhole free, has a large area (2.5 cm × 2.5 cm), and has a low surface roughness (a root mean square of 32 nm). Multiple times of centrifugation and solvent annealing in the MCDSA method are key to improving the quality of the film as well as the laser performance. With increased centrifugation cycles from one to four, the thickness of the film increases from 180 nm to 880 nm, leading to a decrease in the laser threshold from 18.1 µJ cm-2 to 14.2 µJ cm-2 and an increase in the gain coefficient from 78.5 cm-1 to 112.7 cm-1. When solvent annealing is employed, the gain coefficient is further increased to 122.7 cm-1.

14.
Ying Yong Sheng Tai Xue Bao ; 30(10): 3491-3500, 2019 Oct.
Artículo en Chino | MEDLINE | ID: mdl-31621236

RESUMEN

The dynamic simulation of cucumber growth and development in sunlight greenhouse can provide technical support for the intelligent management of cucumber production. According to the cucumber response characteristics to light and temperature, the cucumber development module based on the algorithm of clock model was established by using data from four-stage experiment with 'Jinyou 35' as experiment variety in two years. Based on the relationship between the leaf growth and key meteorological factors (temperature and radiation), leaf area index (LAI) module was established with the accumulated product of thermal effectiveness and photosynthetically active radiation (TEP) as independent variables. The simulation module of cucumber dry matter production was established by taking into consideration the double integral of LAI and daily length in photosynthesis per unit leaf area as well as the respiratory expenditure of different organs. Combined with water content of organs, fresh weight simulation module of cucumber organs was constructed. The whole cucumber development and growth simulation model in greenhouse was built based on each sub-module. The model parameters were calibrated and determined. The results showed that root mean square error (RMSE) of simulated values and observed values of four deve-lopment stages (from transplanting date to stretch tendril, to initial flowering, to early harvested and to uprooting), was 3.9-10.5 d. The normalized root mean square error (nRMSE) was 6.5%-28.6%. The coincidence index (D) was 0.79-0.97. The relationship between LAI and TEP was the regression of 'S' type curve. The RMSE of simulated and observed LAI values was 0.19. The nRMSE was 17.2%. The D value was 0.90. The RMSE of dry weight of root, stem, leaf, flower and fruit of the simulated values and observed values were 0.39-8.94 g·m-2. The nRMSE were 10.9%-17.7%. The D values were all above 0.98. The growth and development model of cucumber could accurately simulate the key development period of cucumber, leaf area and the dry and fresh weight of various organs and quantify the growth and development of cucumber in sunlight greenhouse.


Asunto(s)
Cucumis sativus , Crecimiento y Desarrollo , Fotosíntesis , Hojas de la Planta , Luz Solar
15.
Inorg Chem ; 58(15): 10304-10312, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31328509

RESUMEN

In recent years, although low-dimensional hybrid lead halides have received great attention due to the fascinating photoluminescent (PL) properties, the research is still on the early stage and only limited phases have been explored and characterized. Here, by introducing heterometals as mixed structural compositions and optical activity centers, we prepared a series of low-dimensional hybrid heterometallic halides, namely as, [(Me)-DABCO]2Cu2PbI6, [(Me)2-DABCO]2M5Pb2I13 (M = Cu and Ag) and [(Me)2-DABCO]Ag2PbBr6 (Me = methyl group, DABCO = 1,4-diazabicyclo[2.2.2]octane). These hybrid halides feature a low-dimensional 0D [Cu2PbI6]2- cluster, a 1D [M5Pb2I13]4- chain, and a 2D [Ag2PbBr6]2- layer, respectively, on the basis of corner-, edge- and face-sharing connecting of [MX4] tetrahedrons, [PbX5] quadrangular pyramids, and [PbX6] octahedrons. Under the photoexcitation, these hybrid heterometallic halides exhibit deep-red luminescent emissions from 711 to 801 nm with the largest Stocks shift of 395 nm. The temperature-dependent PL emissions, PL lifetime, and theoretical calculations are also investigated to probe into the intrinsic nature of photoluminescent emissions. This work affords new types of hybrid halides by introducing different metal centers to probe into the structural evolution and photoluminescent properties.

16.
Hortic Res ; 6: 25, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30729015

RESUMEN

SCR/SP11 encodes the male determinant of recognition specificity of self-incompatibility (SI) in Brassica species and is sporophytically expressed in the anther tapetum. Based on dominance relationships in pollen and nucleotide sequence similarity, the S haplotypes in Brassica have been classified as class I or class II, with class-I S haplotypes being dominant over class-II S haplotypes. Here, we revealed that S-22 in B. rapa belonging to class I is recessive to class-II S-44 and class-I S-36 in pollen, whereas it is dominant over S-60, S-40, and S-29 based on pollination tests. SCR/SP11 of S-22 (SCR-22) was sequenced, revealing that the deduced amino-acid sequence of SCR-22 has the longest C-terminal domain among the SCR/SP11 sequences. The expression of SCR-22 was found to be suppressed in S-22/S-44 and S-22/S-36 heterozygotes. Normal transcription of SCR-44 was considered to be due to the transcription suppression of Smi sRNA of the S-22 haplotype and a very low methylation state of the SCR-44 promoter region in the tapetum of S-22/S-44 heterozygotes. In SCR-22, only the cytosine residue located at the -37 bp position of the promoter region was hypermethylated in the tapetum of S-22/S-44 heterozygotes, and few methylated cytosines were detected in the promoter and coding regions of SCR-22 in S-22/S-36 heterozygotes. SCR-22 was also expressed in microspores in S-22 homozygotes but not in S-22/S-44 and S-22/S-36 heterozygotes. These results suggest that a mechanism different from class-II SCR/SP11 suppression may operate for the suppression of recessive class-I SCR-22 in S heterozygotes.

17.
Cancer Sci ; 110(1): 107-117, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30387548

RESUMEN

Gliomas are the most common central nervous system tumors. They show malignant characteristics indicating rapid proliferation and a high invasive capacity and are associated with a poor prognosis. In our previous study, p68 was overexpressed in glioma cells and correlated with both the degree of glioma differentiation and poor overall survival. Downregulating p68 significantly suppressed proliferation in glioma cells. Moreover, we found that the p68 gene promoted glioma cell growth by activating the nuclear factor-κB signaling pathway by a downstream molecular mechanism that remains incompletely understood. In this study, we found that dual specificity phosphatase 5 (DUSP5) is a downstream target of p68, using microarray analysis, and that p68 negatively regulates DUSP5. Upregulating DUSP5 in stably expressing cell lines (U87 and LN-229) suppressed proliferation, invasion, and migration in glioma cells in vitro, consistent with the downregulation of p68. Furthermore, upregulating DUSP5 inhibited ERK phosphorylation, whereas downregulating DUSP5 rescued the level of ERK phosphorylation, indicating that DUSP5 might negatively regulate ERK signaling. Additionally, we show that DUSP5 levels were lower in high-grade glioma than in low-grade glioma. These results suggest that the p68-induced negative regulation of DUSP5 promoted invasion by glioma cells and mediated the activation of the ERK signaling pathway.


Asunto(s)
Neoplasias Encefálicas/genética , ARN Helicasas DEAD-box/genética , Fosfatasas de Especificidad Dual/genética , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Glioma/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , ARN Helicasas DEAD-box/metabolismo , Fosfatasas de Especificidad Dual/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Glioma/metabolismo , Glioma/patología , Humanos , Sistema de Señalización de MAP Quinasas/genética , Invasividad Neoplásica , Fosforilación , Interferencia de ARN
18.
Phys Chem Chem Phys ; 20(31): 20571-20574, 2018 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-30058658

RESUMEN

The electron localization in Nb-doped CaMnO3 is analyzed in terms of the space and energy distribution of electronic states employing first-principles calculations. The energy difference of Mn 3d states and Nb 4d states makes NbO6 octahedra impede electrical conduction, so the random distribution of Nb in lattices leads to the localization of electrons near the bottom of the conduction bands. Therefore, although more carriers are introduced when Nb-doping content increases, both the electrical conductivity and absolute thermopower decrease in Nb heavy doped CaMnO3. The calculated transport properties agree well with the experimental data, supporting the analysis of localization.

19.
J Ultrason ; 17(70): 160-166, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29075520

RESUMEN

OBJECTIVE: The aim of this study was to investigate the usefulness of high-resolution ultrasonography for the diagnosis of polyneuropathy in diabetes mellitus patients by the examination of the ulnar nerves. METHOD: We recruited 100 healthy age-matched volunteers (50 women and 50 men) with 200 arms without diabetes or cubital tunnel syndrome as the control group. We assessed the upper limbs of 100 diabetes mellitus patients (45 women and 55 men), 40 of whom had electrophysiologically confirmed diabetic peripheral neuropathy and 60 had no diabetic peripheral neuropathy in the upper limbs. Age, sex, height and weight were recorded and the cross-sectional area of the ulnar nerve was measured at every predetermined site. RESULTS: The cross-sectional area of the ulnar nerve was measured at six sites (mid-humerus, inlet of the cubital tunnel, outlet of the cubital tunnel, upon the medial epicondyle, 6 cm upon the wrist crease and Guyon tunnel). The ulnar nerve in two measuring sites (mid-humerus, upon the medial epicondyle) in the control group showed a statistical difference between men and women (p < 0.05). There was no statistical difference in the cross-sectional area in the control group when dominant and non-dominant arms were compared. The cross-sectional area was larger in the diabetic peripheral neuropathy group in three sites (inlet of the cubital tunnel, outlet of the cubital tunnel, Guyon tunnel) compared with those in the control group. CONCLUSION: High-resolution ultrasonography may be helpful in the early diagnosis of peripheral neuropathy in diabetic patients.

20.
Inorg Chem ; 56(18): 10962-10970, 2017 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-28846401

RESUMEN

The development of new visible light-driven photocatalysts based on semiconducting materials remains a greatly interesting and challenging task for the purpose of solving the energy crisis and environmental issues. By using photosensitive [(Me)2-2,2'-bipy]2+ (1,1'-dimethyl-2,2'-bipyridinium) cation as template, we synthesized one new type of inorganic-organic hybrid cuprous and silver halogenides of [(Me)2-2,2'-bipy]M8X10 (M = Cu, Ag, X = Br, I). The compounds feature a three-dimensional anionic [M8X10]2- network composed of a one-dimensional [M8X12] chain based on MX4 tetrahedral units. The photosensitization of organic cationic templates results in narrow band gaps of hybrid compounds (1.66-2.06 eV), which feature stable visible light-driven photodegradation activities for organic pollutants. A detailed study of the photocatalytic mechanism, including the photoelectric response, photoluminescence spectra, and theoretical calculations, shows that the organic cationic template effectively inhibits the recombination of photoinduced electron-hole pairs leading to excellent photocatalytic activities and photochemical stabilities.

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