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1.
Nanotechnology ; 31(20): 205707, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32000158

RESUMO

Cadmium telluride (CdTe) nanocrystals with thiol stabilizers have been applied widely in the fields of energy storage and transformation. The aim of this work is to develop anhydrous proton exchange membranes (PEMs) by introducing CdTe nanocrystals bearing thioglycolic acid (tga) or mercaptopropionic acid (mpa) stabilizers into sulfonated poly(ether ether ketone) (SPEEK) and polyurethane (PU) systems. In the prepared SPEEK/PU/CdTe membranes, CdTe nanocrystals could provide desirable properties such as improving mechanical strength and enhancing proton conductivity by combining with phosphoric acid (PA) molecules. Successful preparation of SPEEK/PU/CdTe/PA membranes was demonstrated by the identification of high and stable proton conductivity and satisfactory thermal/chemical stability and mechanical properties. The fine appearance of membranes revealed uniform dispersion of components. Measurements of properties showed that the SPEEK(74%)/PU/CdTe-mpa(20/60/20)/100%PA membrane as a candidate anhydrous PEM is promising for use in high-temperature proton exchange membrane fuel cells. Specifically, the recommended membrane showed a proton conductivity of 1.18 × 10-1 S cm-1 at 160 °C and 3.96 × 10-2 S cm-1 at 100 °C, lasting for 600 h, and a tensile stress of 14.6 MPa at room temperature. Mixing inorganic CdTe nanocrystals with polymers to form inorganic/organic composite membranes is effective for producing anhydrous PEMs with cheaper polymers without functional groups to conduct protons.

2.
Plant Cell Environ ; 43(4): 903-919, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31851373

RESUMO

During maize production, drought throughout the flowering stage usually induces seed abortion and yield losses. The influence of postpollination drought stress on seed abortion and its underlying mechanisms are not well characterized. By intervening in the competition for assimilates between kernel siblings under different degrees of postpollination drought stresses accompanied by synchronous pollination (SP) and incomplete pollination (ICP) approaches, the mechanisms of postpollination abortion were investigated at physiological and molecular levels. Upon SP treatment, up to 15% of the fertilized apical kernels were aborted in the drought-exacerbated competition for assimilates. The aborted kernels exhibited weak sucrose hydrolysis and starch synthesis but promoted the synthesis of trehalose-6-phosphate and ethylene. In ICP where basal pollination was prevented, apical kernel growth was restored with reinstated sucrose metabolism and starch synthesis and promoted sucrose and hexose levels under drought stress. In addition, the equilibrium between ethylene and polyamine in response to the drought and pollination treatments was associated with the abortion process. We conclude that competition for assimilates drives postpollination kernel abortion, whereas differences in sugar metabolism and the equilibrium between ethylene and polyamines may be relevant to the "live or die" choice of kernel siblings during this competition.

3.
Sheng Wu Gong Cheng Xue Bao ; 35(11): 2104-2120, 2019 Nov 25.
Artigo em Chinês | MEDLINE | ID: mdl-31814358

RESUMO

Phthalates esters (PAEs) are important organic compounds used as plasticizers to enhance their plasticity and versatility. At the same time, PAEs are also typical environmental endocrine disruptors. Long-term production and use of plastic products have caused harm to the environment and organisms, as well as human health. Previous studies found that biodegradation has become a main pathway to reduce PAEs in the environment. This article reviews PAEs' structural characteristics and classifications, toxicology, pollution in the environment, summarizes the diversity of PAEs-degrading bacterial species, and explores the possible mechanisms of bacterial PAEs degradation. The article may provide some reference in solving the problem of PAEs pollution.


Assuntos
Biodegradação Ambiental , Ésteres , China , Poluição Ambiental , Ésteres/química , Ésteres/metabolismo , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo , Plastificantes/química , Plastificantes/metabolismo
4.
Orphanet J Rare Dis ; 14(1): 290, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831025

RESUMO

BACKGROUND: Heimler syndrome (HS) is a rare hereditary systemic disorder, partial clinically overlapping with Usher syndrome. So far, our knowledge of HS is very limited, many cases are misdiagnosed or may not even be diagnosed at all. This study aimed to analyze the clinical and genetic characteristics of HS, and to evaluate potential phenotype-genotype correlations. RESULTS: Two HS cases caused by PEX1 mutations were identified, and a novel likely pathogenic mutation, PEX1 c.895_896insTATA, was found. The main ophthalmic finding of the two patients was consistent with retinitis pigmentosa accompanied by cystoid macular edema, but short axial length and hyperopia were also observed as two previously unreported ocular phenotypes. Analysis of the literature showed that of the 29 HS patients previously reported, 12 had PEX6 mutations, 10 had PEX1 mutations, two had PEX26 mutations, and the remaining patients were not genetically tested. Three novel genotype-phenotype correlations were revealed from analysis of these patients. First, most genotypes of every HS patient include at least one missense variant; second, at least one mutation in PEX1 or PEX6 gene affects the AAA-ATPase region in every HS patient with retinal dystrophy, suggesting AAA-ATPase region is a hypermutable region in patients with a retinal dystrophy; third, there are no significant differences between PEX1-, PEX6-, and PEX26-associated phenotypes. CONCLUSION: Next-generation sequencing is important for the diagnosis of HS. This study expands the clinical and genetic spectrum of HS, and provides additional insights into genotype-phenotype correlations, which is vital for accurate clinical practice, genetic counseling, and pathogenesis studies.

5.
BMC Plant Biol ; 19(1): 508, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752685

RESUMO

BACKGROUND: Carbohydrate partitioning and utilization is a key determinant of growth rate and of yield in plants and crops. There are few studies on crops in field conditions. In Arabidopsis, starch accumulation in leaves is a negative indicator of growth rate. RESULTS: Here, we wished to establish if starch accumulation in leaves could potentially be a marker for growth rate and yield in crops such as maize. We characterized daily patterns of non-structural carbohydrate (NSC) at different growth stages over two seasons for maize hybrids in the field. In 27 commercial hybrids, we found a significant negative relationship between residual starch in leaves and plant growth, but not with final yield and biomass. We then focused on three typical hybrids and established a method for calculation of C turnover in photosynthetic leaves that took into account photosynthesis, leaf area and NSC accumulation. The ratios of stored NSC decreased from approximately 15% to less than 4% with ongoing ontogeny changes from V7 to 28 days after pollination. CONCLUSION: The proportion rather than absolute amount of carbon partitioned to starch in leaves at all stages of development related well with yield and biomass accumulation. It is proposed that screening plants at an early vegetative growth stage such as V7 for partitioning into storage may provide a prospective method for maize hybrid selection. Our study provides the basis for further validation as a screening tool for yield.


Assuntos
Carbono/metabolismo , Amido/metabolismo , Zea mays/fisiologia , Ontologias Biológicas , Biomassa , Metabolismo dos Carboidratos , Produtos Agrícolas , Fotossíntese , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Estações do Ano , Zea mays/crescimento & desenvolvimento
6.
Int J Biol Macromol ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31756490

RESUMO

In this study, in order to evaluate the influences of drying methods on the chemical structures and bioactivities of polysaccharides from okra (OPPs), four drying methods, including microwave drying at 400 W, 600 W, and 800 W, freezing drying, hot air drying, and vacuum drying, were applied to dry okra fruits. Six different OPPs were extracted from okra dried by different drying methods. Results showed that physicochemical characteristics and bioactivities of OPPs varied by different drying methods. Noticeable variations in extraction yields, molecular weights, rheological properties, molar ratios of constituent monosaccharides, contents of uronic acids, degrees of esterification, and contents of total phenolics were observed in OPPs obtained by different drying methods. In addition, results showed that OPPs, especially OPP-H and OPP-V obtained by hot air drying and vacuum drying, respectively, exhibited remarkable antioxidant activities (ABTS, DPPH, and nitric oxide radical scavenging activities, and ferric reducing antioxidant powers), strong in vitro binding capacities (fat, cholesterol, and bile acids binding capacities), and obvious inhibitory activities on α-amylase and α-glucosidase. Results suggested that the hot air and vacuum drying techniques could be appropriate drying methods before extraction of OPPs with high bioactivities for applications in the functional food and medicine industries.

7.
Nat Microbiol ; 4(12): 2552-2564, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31659299

RESUMO

Innate immunity is the first line of host defence against pathogens. Suppression of innate immune responses is essential for the survival of all viruses. However, the interplay between innate immunity and HIV/SIV is only poorly characterized. We have discovered Vpx as a novel inhibitor of innate immune activation that associates with STING signalosomes and interferes with the nuclear translocation of NF-κB and the induction of innate immune genes. This new function of Vpx could be separated from its role in mediating degradation of the antiviral factor SAMHD1, and is conserved among diverse HIV-2/SIV Vpx. Vpx selectively suppressed cGAS-STING-mediated nuclear factor-κB signalling. Furthermore, Vpx and Vpr had complementary activities against cGAS-STING activity. Since SIVMAC lacking both Vpx and Vpr was less pathogenic than SIV deficient for Vpr or Vpx alone, suppression of innate immunity by HIV/SIV is probably a key pathogenic determinant, making it a promising target for intervention.

8.
Appl Opt ; 58(19): 5143-5147, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503607

RESUMO

We have experimentally demonstrated a wavelength-tunable passively mode-locked all-fiber laser at 1.5 µm wavelength by using an erbium-doped fiber amplifier, a fiber-pigtailed semiconductor saturable absorber mirror, and a tunable birefringence Sagnac filter. In our work, by properly setting the polarization state of the propagating light in the birefringence Sagnac filter, the mode-locked lasing wavelength can be continuously tuned from 1544.1 to 1560.8 nm, corresponding to a tuning range of 16.7 nm. At a central wavelength of 1548.5 nm, the fiber laser delivers pulses as short as 713.2 fs with a repetition rate of 4.65 MHz, a 3 dB bandwidth of 5.7 nm, and an average output power of 4.86 mW. Our results show that such a mode-locked all-fiber laser has great potential in applications in nonlinear optics at the 1.5 µm band.

9.
Front Genet ; 10: 773, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31543898

RESUMO

Purpose: To clarify the mutation spectrum and frequency of ABCA4 in a Chinese cohort with Stargardt disease (STGD1). Methods: A total of 153 subjects, comprising 25 families (25 probands and their family members) and 71 sporadic cases, were recruited for the analysis of ABCA4 variants. All probands with STGD1 underwent a comprehensive ophthalmologic examination. Overall, 792 genes involved in common inherited eye diseases were screened for variants by panel-based next-generation sequencing (NGS). Variants were filtered and analyzed to evaluate possible pathogenicity. Results: The total variant detection rate of at least one ABCA4 mutant allele was 84.3% (129/153): two or three disease-associated variants in 86 subjects (56.2%), one mutant allele in 43 subjects (28.1%), and no variants in 24 subjects (15.7%). Ninety-six variants were identified in the total cohort, which included 62 missense (64%), 15 splicing (16%), 11 frameshift (12%), 6 nonsense (6%), and 2 small insertion or deletion (2%) variants. Thirty-seven novel variants were found, including a de novo variant, c.4561delA. The most prevalent variant was c.101_106delCTTTAT (10.5%), followed by c.2894A > G (6.5%) and c.6563T > C (4.6%), in STGD1 patients from eastern China. Conclusion: Thirty-seven novel variants were detected using panel-based NGS, including one de novo variant, further extending the mutation spectrum of ABCA4. The common variants in a population from eastern China with STGD1 were also identified.

10.
BMC Complement Altern Med ; 19(1): 198, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375092

RESUMO

BACKGROUND: Endothelial cell inflammation is a central event in the pathogenesis of numerous cardiovascular diseases, including sepsis and atherosclerosis. Triptolide, a principal bioactive ingredient of Traditional Chinese Medicine Tripterygium wilfordii Hook.F., displays anti-inflammatory actions in vivo. However, the mechanisms underlying these beneficial effects remain undetermined. The present study investigated the effects and possible mechanisms of triptolide on lipopolysaccharide (LPS)-induced inflammatory responses in human umbilical vein endothelial cells (HUVECs). METHODS: The effects of triptolide on the LPS-induced production and expression of inflammatory molecules, monocyte adhesion and activation of nuclear factor (NF)-κB pathway were examined in cultured HUVECs. RESULTS: In cultured HUVECs, pre-treatment with triptolide dose-dependently attenuated LPS-induced cytokine and chemokine production, adhesion molecule expression and monocyte adhesion. Mechanistically, triptolide was found to dose-dependently inhibit the LPS-induced increases in the DNA binding activity of NF-κB p65 associated with attenuating IκBα phosphorylation and its degradation. Additionally, the present study revealed that triptolide inhibited LPS-triggered NF-κB transcriptional activation in a dose-dependent manner. CONCLUSIONS: The results of the present study indicated that triptolide suppresses the inflammatory response of endothelial cells possibly via inhibition of NF-κB activation.


Assuntos
Anti-Inflamatórios/farmacologia , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , NF-kappa B/imunologia , Fenantrenos/farmacologia , Tripterygium/química , Compostos de Epóxi/farmacologia , Células Endoteliais da Veia Umbilical Humana/imunologia , Humanos , Lipopolissacarídeos/efeitos adversos , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Inibidor de NF-kappaB alfa/genética , Inibidor de NF-kappaB alfa/imunologia , NF-kappa B/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
11.
Opt Lett ; 44(15): 3793-3796, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31368970

RESUMO

We report the generation of single negatively charged silicon vacancy (SiV-) color centers by focusing a femtosecond (fs) laser on top of a high-purity diamond coated with a layer of Si nanoball. Under the interaction of a high-intensity fs laser, Si atoms were ionized and implanted into the diamond, accompanied with the creation of vacancies. After annealing at 850°C in vacuum for 1 h, the photoluminescence spectra of bright spots around the created crater presented a typical strong zero-phonon line at around 737 nm of SiV- centers. Bright single SiV- color centers could be observed with a maximum saturating counting rate of 300×103 counts/s. We explain the formation mechanism of SiV- centers in diamond via a Coulomb explosion model. The results demonstrate that fs laser ablation can be utilized as a very promising tool to conveniently fabricate single bright SiV- centers in diamond.

12.
Mol Oncol ; 13(12): 2554-2573, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31369196

RESUMO

Accumulating evidence has established that long noncoding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) is a tumor regulator in many cancers. Here, we aimed to investigate the possible function of lncRNA PVT1 in esophageal carcinoma (EC) via targeting of microRNA-145 (miR-145). Initially, microarray-based gene expression profiling of EC was employed to identify differentially expressed genes. Moreover, the expression of lncRNA PVT1 was examined and the cell line presenting with the highest level of lncRNA PVT1 expression was selected for subsequent experiments. We then proceeded to examine interaction among lncRNA PVT1, FSCN1, and miR-145. The effect of lncRNA PVT1 on viability, migration, invasion, apoptosis, and tumorigenesis of transfected cells was examined with gain-of-function and loss-of-function experiments. We observed that lncRNA PVT1 was robustly induced in EC. lncRNA PVT1 could bind to miR-145 and regulate its expression, and FSCN1 is a target gene of miR-145. Overexpression of miR-145 or silencing of lncRNA PVT1 was revealed to suppress cell viability, migration, and invasion abilities, while also stimulating cell apoptosis. Furthermore, our in vivo results showed that overexpression of miR-145 or silencing of lncRNA PVT1 resulted in decreased tumor growth in nude mice. In conclusion, our research reveals that down-regulation of lncRNA PVT1 could potentially promote expression of miR-145 to repress cell migration and invasion, and promote cell apoptosis through the inhibition of FSCN1. This highlights the potential of lncRNA PVT1 as a therapeutic target for EC treatment.

13.
J Plant Physiol ; 240: 153007, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31310905

RESUMO

Previous studies have proven that graphene oxide (GO) regulates abscisic acid (ABA) and indole-3-acetic acid (IAA) contents and modulates plant root growth. To better understand the mechanism of plant growth and development regulated by GO and crosstalk between ABA and GO, Zhongshuang No. 9 seedlings were treated with GO and ABA. The results indicated that GO and ABA significantly affected the morphological properties and endogenous phytohormone contents in seedlings, and there was significant crosstalk between GO and ABA. ABA treatments combined with GO led to a rapid decrease in triphenyltetrazolium chloride (TTC) reduction intensity, and the inhibitory effect was enhanced with increasing ABA concentration. The treatments significantly affected the transcriptional levels of some key genes involved in the ABA, IAA, cytokinin (CTK), salicylic acid (SA), and ethane (ETH) pathways and increased the ABA and gibberellin (GA) contents in rapeseed seedlings. The effects of the treatments on the IAA and CTK contents were complex, but, importantly, the treatments suppressed root elongation. Correlation analysis also indicated that the relationship between root length and IAA/ABA could be described by a polynomial function: y = 88.11x2 - 25.15x + 4.813(R²â€¯= 0.912). The treatments increased the ACS2 transcript abundance for ETH biosynthesis and the ICS1 transcriptional level of the key genes involved in salicylic acid (SA) biosynthesis, as well as the downstream signaling genes CBP60 and SARD1. This finding indicated that ABA is an important factor regulating the effects of GO on the growth and development of Brassica napus L., and that ETH and SA pathways may be potential pathways involved in the response of rape seedlings to GO treatment.


Assuntos
Ácido Abscísico/administração & dosagem , Brassica napus/crescimento & desenvolvimento , Grafite/administração & dosagem , Ácidos Indolacéticos/metabolismo , Reguladores de Crescimento de Planta , Ácido Abscísico/metabolismo , Brassica napus/efeitos dos fármacos , Brassica napus/enzimologia , Brassica napus/metabolismo , Reguladores de Crescimento de Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/enzimologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
14.
Clin J Sport Med ; 29(4): 312-317, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31241534

RESUMO

OBJECTIVE: To investigate the effects of long-term diving on the morphology and growth of the distal radial epiphyseal plate in young divers. STUDY DESIGN: Cohort study. SETTING: Guangzhou Sport University. PARTICIPANTS: Thirty-eight professional divers, aged 10 to 17 years, and 25 age-matched volunteers. INTERVENTIONS: Each subject received a physical examination at the beginning of the study and underwent bilateral magnetic resonance imaging of the wrist. The divers were divided into 2 groups depending on the status of the epiphyseal plate: group A (positive distal radial epiphyseal plate injury) and group B (no positive distal radial epiphyseal plate injury). A third group, group C, consisted of the 25 volunteers. MAIN OUTCOME MEASURES: The frequency of distal radial epiphyseal plate injury and the thickness of the distal radial epiphyseal plate were analyzed across the 3 groups. RESULTS: Twenty-nine cases (29/76, 38.15%) of distal radial epiphyseal plate injury were observed in 20 divers (20/38, 52.63%). The incidence of injury to the right hand was higher than that for the left (P = 0.009). There were statistically significant differences (P = 0.000) among the 3 groups in terms of epiphyseal plate thickness; group A > group B > group C. CONCLUSIONS: Distal radial epiphyseal plate injury is common in divers, and more injuries are seen in the right hand. Moreover, growth of the radius was impaired in divers relative to controls. We consider that loading during diving may influence growth of the epiphyseal plate in either a transient or permanent manner.


Assuntos
Mergulho/lesões , Epífises/diagnóstico por imagem , Epífises/lesões , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/lesões , Adolescente , Traumatismos em Atletas/epidemiologia , Estudos de Casos e Controles , Criança , Estudos de Coortes , Epífises/crescimento & desenvolvimento , Feminino , Humanos , Imagem por Ressonância Magnética , Masculino , Rádio (Anatomia)/crescimento & desenvolvimento
15.
Chin Med J (Engl) ; 132(12): 1406-1413, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31205097

RESUMO

BACKGROUND: The long-term predicted value of microvolt T-wave alternans (MTWA) for ventricular tachyarrhythmia in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) remains unclear. Our study explored the characteristics of MTWA and its prognostic value when combined with an electrophysiologic study (EPS) in patients with ARVC. METHODS: All patients underwent non-invasive MTWA examination with modified moving average (MMA) analysis and an EPS. A positive event was defined as the first occurrence of sudden cardiac death, documented sustained ventricular tachycardia (VT), ventricular fibrillation, or the administration of appropriate implantable cardioverter defibrillator therapy including shock or anti-tachycardia pacing. RESULTS: Thirty-five patients with ARVC (age 38.6 ±â€Š11.0 years; 28 males) with preserved left ventricular (LV) function were recruited. The maximal TWA value (MaxValt) was 17.0 (11.0-27.0) µV. Sustained VT was induced in 22 patients by the EPS. During a median follow-up of 99.9 ±â€Š7.7 months, 15 patients had positive clinical events. When inducible VT was combined with the MaxValt, the area under the curve improved from 0.739 to 0.797. The receiver operating characteristic curve showed that a MaxValt of 23.5 µV was the optimal cutoff value to identify positive events. The multivariate Cox regression model for survival showed that MTWA (MaxValt, hazard ratio [HR], 1.06; 95% confidence interval [CI], 1.01-1.11; P = 0.01) and inducible VT (HR, 5.98; 95% CI, 1.33-26.8; P = 0.01) independently predicted positive events in patients with ARVC. CONCLUSIONS: MTWA assessment with MMA analysis complemented by an EPS might provide improved prognostic ability in patients with ARVC with preserved LV function during long-term follow-up.


Assuntos
Arritmias Cardíacas/diagnóstico , Displasia Arritmogênica Ventricular Direita/diagnóstico , Eletrocardiografia/métodos , Eletrofisiologia/métodos , Taquicardia Ventricular/diagnóstico , Adulto , Teste de Esforço , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Função Ventricular Esquerda/fisiologia
16.
Front Plant Sci ; 10: 506, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31057596

RESUMO

Flowering plants depend on pollination and fertilization to activate the transition from ovule to seed and ovary to fruit, namely seed and fruit set, which are key for completing the plant life cycle and realizing crop yield potential. These processes are highly energy consuming and rely on the efficient use of sucrose as the major nutrient and energy source. However, it remains elusive as how sucrose imported into and utilizated within the female reproductive organ is regulated in response to pollination and fertilization. Here, we explored this issue in tomato by focusing on genes encoding cell wall invertase (CWIN) and sugar transporters, which are major players in sucrose phloem unloading, and sink development. The transcript level of a major CWIN gene, LIN5, and CWIN activity were significantly increased in style at 4 h after pollination (HAP) in comparison with that in the non-pollination control, and this was sustained at 2 days after pollination (DAP). In the ovaries, however, CWIN activity and LIN5 expression did not increase until 2 DAP when fertilization occurred. Interestingly, a CWIN inhibitor gene INVINH1 was repressed in the pollinated style at 2 DAP. In response to pollination, the style exhibited increased expressions of genes encoding hexose transporters, SlHT1, 2, SlSWEET5b, and sucrose transporters SlSUT1, 2, and 4 from 4 HAP to 2 DAP. Upon fertilization, SlSUT1 and SlHT1 and 2, but not SlSWEETs, were also stimulated in fruitlets at 2 DAP. Together, the findings reveal that styles respond promptly and more broadly to pollination for activation of CWIN and sugar transporters to fuel pollen tube elongation, whereas the ovaries do not exhibit activation for some of these genes until fertilization occurs. Highlights: Expression of genes encoding cell wall invertases and sugar transporters was stimulated in pollinated style and fertilized ovaries in tomato.

17.
Mol Med Rep ; 19(6): 5105-5114, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059076

RESUMO

Portal hypertension is the primary cause of complications in patients with chronic liver diseases, and markedly impacts metabolism within the nervous system. Until recently, the role of portal hypertension in hepatocellular metabolism was unclear. The present study demonstrated that an increase in extracellular pressure significantly decreased hepatocellular glycogen concentrations in HepG2 and HL­7702 cells. In addition, it reduced glycogen synthase activity, by inhibiting the phosphorylation of glycogen synthase 1. RNA­seq analysis revealed that mechanical pressure suppressed glycogen synthesis by activating the p53/phosphatase and tensin homolog pathway, further suppressing glycogen synthase activity. The present study revealed an association between mechanical pressure and hepatocellular glycogen metabolism, and identified the regulatory mechanism of glycogen synthesis under pressure.


Assuntos
Glicogênio/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Glicogênio Sintase/genética , Glicogênio Sintase/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Fosforilação , Pressão , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
18.
Mol Med Rep ; 20(1): 375-387, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31115518

RESUMO

Mechanical pressure may contribute to the development of cancer; however, there is currently no evidence regarding the effect of mechanical pressure on liver cancer. In the present study, 2­ and 3­dimensional pressure­loading systems were used to exert pressure on HepG2 and Huh­7 cell lines. Cell proliferation and flow cytometry analyses were undertaken to observe the proliferative ability of pressure­loaded cells. In addition, Transwell, wound­healing and reverse transcription­quantitative polymerase chain reaction (RT­qPCR) assays were applied to evaluate the migratory and invasive ability of pressurized cells. Analyses of microRNA (miRNA) and mRNA expression profiles were performed to screen for differentially expressed miRNAs and mRNAs, which were validated by RT­qPCR. Bioinformatics analyses were subsequently performed to investigate the putative target genes and associated pathways. The proliferation and invasion of HepG2 and Huh­7 cell lines were significantly increased under a pressure of 15 mmHg for 24 h. Under this condition, five differentially expressed miRNAs (fold change ≥1.2, P≤0.05) and 10,150 differentially expressed mRNAs (fold change ≥2, P≤0.05) were identified. A total of 1,309 genes were identified from the integrative analysis of miRNAs and mRNAs. In addition, the bioinformatics analyses revealed that the majority of these miRNAs and mRNAs were associated with several pathways associated with cell proliferation and invasion, including 'PI3K/Akt signaling pathway', 'focal adhesion', 'integrin­mediated signaling pathway', 'FOXO signaling pathway' and 'Hippo signaling pathway'. The present study described the pressure­dependent proliferation and invasion of liver cancer cells, and revealed the potential molecular mechanisms underlying them. The identification of miRNAs and their putative targets may also result in novel treatment strategies for liver cancer.


Assuntos
Neoplasias Hepáticas/genética , MicroRNAs/genética , Pressão , RNA Mensageiro/genética , Proliferação de Células/genética , Biologia Computacional , Regulação Neoplásica da Expressão Gênica/genética , Células Hep G2 , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Transdução de Sinais/genética
19.
J Agric Food Chem ; 67(8): 2408-2419, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30721059

RESUMO

The effects of blue (BL) and green light (GL) treatment during the dark period were examined in Camellia sinensis as a first step to understanding the spectral effects of artificial BL and GL on plant secondary metabolism and light signaling interactions. BL could induce the expression of CRY2/3, SPAs, HY5, and R2R3-MYBs to promote the accumulation of anthocyanins and catechins in tea plants. GL, on the other hand, could stimulate the accumulation of several functional substances (e.g., procyanidin B2/B3 and l-ascorbate) and temper these BL responses via down-regulation of  CRY2/3 and PHOT2. Furthermore, the molecular events that triggered by BL and GL signals were partly overlapped with abiotic/biotic stress responses. We indicate the possibility of a targeted use of BL and GL to regulate the amount of functional metabolites to enhance tea quality and taste, and to potentially trigger defense mechanisms of tea plants.


Assuntos
Camellia sinensis/crescimento & desenvolvimento , Camellia sinensis/efeitos da radiação , Flavonoides/biossíntese , Folhas de Planta/química , Camellia sinensis/química , Camellia sinensis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Luz , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Folhas de Planta/efeitos da radiação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Chá/química , Transcriptoma/efeitos da radiação
20.
Biochem Genet ; 57(4): 555-570, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30734883

RESUMO

Camellia sinensis (L.) O. Kuntze is one of the most important non-alcoholic beverage crops in Asian and African countries. In recent years, many green tea cultivars have been released and played an important role in improving the production and quality of tea trees. The objectives of this study were to assess the genetic diversity of the eighteen main green tea cultivars in Zhejiang Province-the most famous green tea-producing area of China-using start codon-targeted (SCoT) markers and to develop a specific sequence-characterized amplified region (SCAR) marker for application in cultivar diagnosis. Thirty-one SCoT primers produced 264 loci, 226 of which were polymorphic. The genetic similarity coefficients among these green tea cultivars ranged from 0.587 to 0.814, indicating that a high level of genetic diversity was present. Both a UPGMA dendrogram and a PCoA plot grouped the tea cultivars into three groups. The partitioning of groups in the UPGMA and PCoA was similar, and much of the clustering was highly consistent with the classification of tea cultivars according to their genetic backgrounds. A unique SCoT band, SCoT4-1649, specific to the tea cultivar 'Yingshuang,' was transformed into a SCAR marker. This SCAR marker is highly useful for the identification and germplasm conservation of green tea cultivars.


Assuntos
Camellia sinensis/genética , Sequência de Bases , China , Códon de Iniciação , Primers do DNA/genética , DNA de Plantas/genética , Marcadores Genéticos , Variação Genética , Melhoramento Vegetal , Reação em Cadeia da Polimerase , Chá/genética
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