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1.
BMC Vet Res ; 16(1): 43, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019556

RESUMO

BACKGROUND: Endothelial colony forming cells (ECFCs) may be useful therapeutically in conditions with poor blood supply, such as distal limb wounds in the horse. Encapsulation of ECFCs into injectable hydrogel microspheres may ensure cell survival and cell localization to improve neovascularization and healing. Autologous ECFCs were isolated from 6 horses, labeled with quantum nanodots (QD), and a subset were encapsulated in poly(ethylene) glycol fibrinogen microspheres (PEG-Fb MS). Full-thickness dermal wounds were created on each distal limb and injected with empty PEG-Fb MS, serum, ECFCs, or ECFCs encapsulated into PEG- Fb MS (ECFC/MS). Analysis included wound surface area (WSA), granulation tissue scoring (GS), thermography, collagen density staining, and immunohistochemical staining for endothelial and inflammatory cells. The purpose of this study was to track cell location and evaluate wound vascularization and inflammatory response after injection of ECFC/MS or naked ECFCs in equine distal limb wounds. RESULTS: ECFCs were found near and within newly formed blood vessels up to 3 weeks after injection. ECFC and ECFC/MS groups had the greatest blood vessel quantity at week 1 in the wound periphery. Wounds treated with ECFCs and ECFC/MS had the lowest density of neutrophils and macrophages at week 4. There were no significant effects of ECFC or ECFC/MS treatment on other measured parameters. CONCLUSIONS: Injection of microsphere encapsulated ECFCs was practical for clinical use and well-tolerated. The positive ECFC treatment effects on blood vessel density and wound inflammation warrant further investigation.

2.
Medicine (Baltimore) ; 99(3): e18847, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32011502

RESUMO

BACKGROUND: Acupuncture has been widely used to treat primary dysmenorrhea (PD) with satisfactory outcomes. Sanyinjiao (SP6) is the most commonly used acupoint for PD. Different needling techniques may influence the effect of SP6, and its underlying mechanism needs to be explored. This randomized controlled parallel trial is designed to evaluate the immediate analgesic effect and hemodynamic responses in uterine arterial blood flow of perpendicular needling and transverse needling at SP6 in patients with PD of cold-dampness stagnation pattern using color doppler ultrasonography. METHODS: Forty-eight patients who meet inclusion criteria will be randomized in a ratio of 1:1 to either perpendicular needling or transverse needling groups. Every participant will receive 1 session of acupuncture treatment for 10 minutes at bilateral SP6. In the perpendicular needling group, needles will be inserted vertically 1 to 1.2 cun and will be manipulated to achieve needling sensation. In transverse needling group, the needles will be inserted transversely 1 to 1.2 cun toward the abdomen without any manipulation to avoid needling sensation. Color doppler ultrasonography will be performed before, during, and after needling. The primary outcome measure is visual analog scale for pain. The secondary outcome measures include the uterine artery blood flow changes by measuring pulsatility index, resistance index values, and ratio of systolic peak and diastolic peak, the Hamilton anxiety scale, blood pressure, and heart rate. Adverse events in both groups also will be recorded. DISCUSSION: This trial will be the first study protocol designed to explore the influence of needling techniques on the analgesia effect of solo acupoint and its hemodynamic responses for PD. It will promote more widespread awareness of the benefits of using suitable needling techniques in acupuncture clinical setting and provide a further explanation of the underlying hemodynamic mechanism. TRIAL REGISTRATION: This study protocol was registered at the Chinese clinical trial registry (ChiCTR1900026051).

3.
Science ; 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32001526

RESUMO

Mammalian SWI/SNF family chromatin remodelers, BAF and PBAF, regulate chromatin structure and transcription, with their mutations linked to cancers. The 3.7 Å-resolution cryo-EM structure of human BAF bound to nucleosome reveals that the nucleosome is sandwiched by the Base and the ATPase modules, which are bridged by the actin-related protein (ARP) module. The ATPase motor is positioned proximal to nucleosomal DNA and, upon ATP hydrolysis, would engage with and pump DNA along the nucleosome. The C-terminal α-helix of SMARCB1, enriched in positively charged residues frequently mutated in cancers, mediates interactions with an acidic patch of nucleosome. ARID1A and SMARCC serve as a structural core and scaffold in the Base module organization, respectively. Our study provides structural insights into subunit organization and nucleosome recognition of human BAF complex.

4.
Am J Psychiatry ; : appiajp201919030324, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32046533

RESUMO

OBJECTIVE: At first hospitalization, a long duration of untreated psychosis (DUP) predicts illness severity and worse treatment outcomes. The mechanism of this association, however, remains unclear. It has been hypothesized that lengthy untreated psychosis is toxic or that it reflects a more severe form of schizophrenia. Alternatively, the association may be an artifact of lead-time bias. These hypotheses are tested in a longitudinal study of schizophrenia with 2,137 observations spanning from childhood to 20 years after first admission. METHODS: Data were from the Suffolk County Mental Health Project. The cohort included 287 individuals with schizophrenia or schizoaffective disorder. DUP was defined as days from first psychotic symptom to first psychiatric hospitalization. Psychosocial function was assessed using the Premorbid Adjustment Scale and the Global Assessment of Functioning Scale. Psychosocial function trajectories were estimated using multilevel spline regression models adjusted for gender, occupational status, race, and antipsychotic medication. RESULTS: Both long- and short-DUP patients experienced similar declines in psychosocial function, but declines occurred at different times relative to first admission. Long-DUP patients experienced most of these declines prior to first admission, while short-DUP patients experienced declines after first admission. When psychosocial function was analyzed relative to psychosis onset, DUP did not predict illness course. CONCLUSIONS: The association between DUP and psychosocial function may be an artifact of early detection, creating the illusion that early intervention is associated with improved outcomes. In other words, DUP may be better understood as an indicator of illness stage than a predictor of course.

5.
J Pharm Biomed Anal ; 182: 113110, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32004768

RESUMO

Callicarpa nudiflora, belonging to the family Verbenaceae, is widely used to treat inflammation caused by bacterial infection.However, the underlying active substances of C. nudiflora against inflammation remains obscure. In this work, an ultra high-performance liquid chromatography (UHPLC) coupled with quadrupole time-of-flight mass spectrometry method was developed to characterize the ingredients in C. nudiflora, and a validated UHPLC coupled with triple quadrupole tandem mass spectrometry method was applied to quantify major components. As a result, a total of 96 chemical compounds were identified in C. nudiflora, and 26 compounds of them were further quantified in 34 batches of C. nudiflora. Based on the identified components from C. nudiflora, a compound-target network for the anti-inflammation effect was constructed by reverse docking target prediction, disease associated genes screening in DisGeNET and the protein-protein interaction from STRING. The compound-target network showed that C. nudiflora might exert anti-inflammation effect on the target of complement 3 and 5 in the pathway of cells and molecules involved in local acute inflammatory response, and 16 effective candidate compounds were found such as catalpol, acteoside, rutin, etc. This study provided an opportunity to deepen the understanding of the chemical composition and the potential anti-inflammatory mechanism of C. nudiflora.

6.
Chin J Traumatol ; 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-32057563

RESUMO

Trauma is the leading cause of death in people under the age of 45 years, and it has gained wide attention from academics worldwide. Therefore, more and more studies have reported on trauma and related fields in recent decades. In 2019, Chinese Journal of Traumatology (CJTEE) published 69 articles covering traffic medicine, wound healing, bone trauma, emergency care, and other hot topics of traumatology. Here we reviewed a series of articles published in CJTEE on the topics mentioned above, try to give a brief introduction of progress in trauma field.

7.
Nucleic Acids Res ; 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31970415

RESUMO

Genomic instability is an underlying hallmark of cancer and is closely associated with defects in DNA damage repair (DDR). Chromatin relaxation is a prerequisite for DDR, but how chromatin accessibility is regulated remains elusive. Here we report that the histone deacetylase SIRT6 coordinates with the chromatin remodeler CHD4 to promote chromatin relaxation in response to DNA damage. Upon DNA damage, SIRT6 rapidly translocates to DNA damage sites, where it interacts with and recruits CHD4. Once at the damage sites, CHD4 displaces heterochromatin protein 1 (HP1) from histone H3 lysine 9 trimethylation (H3K9me3). Notably, loss of SIRT6 or CHD4 leads to impaired chromatin relaxation and disrupted DNA repair protein recruitment. These molecular changes, in-turn, lead to defective homologous recombination (HR) and cancer cell hypersensitivity to DNA damaging agents. Furthermore, we show that SIRT6-mediated CHD4 recruitment has a specific role in DDR within compacted chromatin by HR in G2 phase, which is an ataxia telangiectasia mutated (ATM)-dependent process. Taken together, our results identify a novel function for SIRT6 in recruiting CHD4 onto DNA double-strand breaks. This newly identified novel molecular mechanism involves CHD4-dependent chromatin relaxation and competitive release of HP1 from H3K9me3 within the damaged chromatin, which are both essential for accurate HR.

8.
Soft Matter ; 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31998920

RESUMO

The motion of nanoparticles on soft surfaces is the result of interplay between capillary, elastic and friction forces. To elucidate the importance of the different contributions controlling nanoparticle rolling dynamics on soft surfaces, we performed molecular dynamics simulations of solid nanoparticles in contact with soft elastic substrates. The nanoparticle motion is initiated by applying a constant force resulting in stationary, steady rolling, and accelerating states, depending on the nanoparticle-substrate work of adhesion, W, the magnitude of the net applied force, F, and the substrate shear modulus G. In the stationary state, the restoring torque produced in the contact area balances the torque due to the external force. The rolling force Fr, determining the crossover to the rolling state, is proportional to the product of the work of adhesion W and nanoparticle size Rp, Fr ∼ WRp. In the steady rolling state, F > Fr, the nanoparticle maintains a constant rolling velocity which is a manifestation of the balance between the rolling friction force and the applied force. The observed scaling relationships between the applied force and nanoparticle velocity reflect a viscoelastic nature of the substrate deformation dynamics. A nanoparticle begins to accelerate when the energy supplied to the nanoparticle exceeds the energy dissipated in the contact area due to viscoelastic substrate deformation. Using these simulation results, we have constructed a diagram of states in terms of the dimensionless parameters F/WRp and W/GRp.

9.
Plant Cell Environ ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31899547

RESUMO

Most land plants can form symbiosis with arbuscular mycorrhizal (AM) fungi to enhance uptake of mineral nutrients, particularly phosphate (Pi) and nitrogen (N), from the soil. It is established that transport of Pi from interfacial apoplast into plant cells depends on the H+ gradient generated by the H+ -ATPase located on the periarbuscular membrane (PAM); however, little evidence regarding the potential link between mycorrhizal N transport and H+ -ATPase activity is available to date. Here, we report that a PAM-localized tomato H+ -ATPase, SlHA8, is indispensable for arbuscule development and mycorrhizal P and N uptake. Knockout of SlHA8 resulted in truncated arbuscule morphology, reduced shoot P and N accumulation, and decreased H+ -ATPase activity and acidification of apoplastic spaces in arbusculated cells. Overexpression of SlHA8 in tomato promoted both P and N uptake, and increased total colonization level, but did not affect arbuscule morphology. Heterogeneous expression of SlHA8 in the rice osha1 mutant could fully complement its defects in arbuscule development and mycorrhizal P and N uptake. Our results propose a pivotal role of the SlHA8 in energizing both the symbiotic P and N transport, and highlight the evolutionary conservation of the AM-specific H+ -ATPase orthologs in maintaining AM symbiosis across different mycorrhizal plant species.

10.
Eur J Med Chem ; 189: 112038, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31945667

RESUMO

Bufadienolides are a type of natural cardiac steroids and originally isolated from the Traditional Chinese Medicine Chan'Su, they have been used for the treatment of heart disease in traditional remedies as well as in modern medicinal therapy with potent anti-tumor activities. Due to their unique molecular structures with unsaturated six-membered lactones attached to the steroid core, bufadienolides have received great attention in the synthetic organic community. This review presents total synthetic efforts to some representative bufadienolides, chemical modification of bufadienolides will also be given to discuss their structure-activity relationship in anti-tumor.

11.
Toxicology ; 431: 152365, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31926186

RESUMO

Perfluorooctane sulfonate (PFOS) is a persistent environmental chemical whose biological effects are mediated by multiple mechanisms. Recent evidence suggests that the gut microbiome may be directly impacted by and/or alter the fate and effects of environmental chemicals in the host. Thus, the aim of this study was to determine whether PFOS influences the gut microbiome and its metabolism, and the host metabolome. Four groups of male C57BL/6 J mice were fed a diet with or without 0.003 %, 0.006 %, or 0.012 % PFOS, respectively. 16S rRNA gene sequencing, metabolomic, and molecular analyses were used to examine the gut microbiota of mice after dietary PFOS exposure. Dietary PFOS exposure caused a marked change in the gut microbiome compared to controls. Dietary PFOS also caused dose-dependent changes in hepatic metabolic pathways including those involved in lipid metabolism, oxidative stress, inflammation, TCA cycle, glucose, and amino acid metabolism. Changes in the metabolome correlated with changes in genes that regulate these pathways. Integrative analyses also demonstrated a strong correlation between the alterations in microbiota composition and host metabolic profiles induced by PFOS. Further, using isolated mouse cecal contents, PFOS exposure directly affected the gut microbiota metabolism. Results from these studies demonstrate that the molecular and biochemical changes induced by PFOS are mediated in part by the gut microbiome, which alters gene expression and the host metabolome in mice.

12.
Leukemia ; 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31896781

RESUMO

Effective treatment of some types of cancer can be achieved by modulating cell lineage-specific rather than tumor-specific targets. We conducted a systematic search for novel agents selectively toxic to cells of hematopoietic origin. Chemical library screenings followed by hit-to-lead optimization identified OT-82, a small molecule with strong efficacy against hematopoietic malignancies including acute myeloblastic and lymphoblastic adult and pediatric leukemias, erythroleukemia, multiple myeloma, and Burkitt's lymphoma in vitro and in mouse xenograft models. OT-82 was also more toxic towards patients-derived leukemic cells versus healthy bone marrow-derived hematopoietic precursors. OT-82 was shown to induce cell death by inhibiting nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the salvage pathway of NAD synthesis. In mice, optimization of OT-82 dosing and dietary niacin further expanded the compound's therapeutic index. In toxicological studies conducted in mice and nonhuman primates, OT-82 showed no cardiac, neurological or retinal toxicities observed with other NAMPT inhibitors and had no effect on mouse aging or longevity. Hematopoietic and lymphoid organs were identified as the primary targets for dose limiting toxicity of OT-82 in both species. These results reveal strong dependence of neoplastic cells of hematopoietic origin on NAMPT and introduce OT-82 as a promising candidate for the treatment of hematological malignancies.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31943783

RESUMO

OBJECTIVES: We evaluated the safety and usefulness of preparatory anatomical reshaping with a geometric hourglass-shaped balloon to optimize transcatheter aortic valve replacement (TAVR) outcomes in bicuspid aortic valve (BAV) stenosis. BACKGROUND: TAVR has been increasingly performed for BAV stenosis; however, technical challenges remain. Procedural results are suboptimal given unfavorable valvular anatomies. METHODS: Eligible patients with BAV stenosis were enrolled to undergo aortic valve predilatation with the hourglass-shaped TAV8 balloon before TAVR using the self-expandable Venus A-Valve. Procedural details and outcomes were compared to a sequential group of patients with BAV who underwent TAVR with the same device following preparatory dilatation using a cylindrical balloon. RESULTS: A total of 22 patients were enrolled in the TAV8 group and 53 were included in the control group. Valve downsizing was less common in the TAV8 group (36.4 vs. 67.9%; p = .012). Stable valve release and optimal implant depth were consistently achieved in the TAV8 group with no requirement for a second valve (0 vs. 17.0%; p = .039) and with higher device success rates (100.0 vs 77.4%; p = .014). Residual aortic regurgitation graded as ≥mild was less common in the TAV8 group (13.6 vs 45.3%; p = .009). Mortality was similar (0 vs. 3.8%; p = 1); no major/disabling stroke or conversion to open-heart surgery was seen in either group within 30 days. CONCLUSIONS: Compared with standard cylindrical balloon valvuloplasty, preparatory reshaping with the hourglass-shaped balloon before self-expandable TAVR in BAV was associated with significantly better procedural results and may encourage more promising outcomes.

14.
Nat Commun ; 11(1): 65, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31900420

RESUMO

Symmetry and topology are two fundamental aspects of many quantum states of matter. Recently new topological materials, higher-order topological insulators, were discovered, featuring bulk-edge-corner correspondence that goes beyond the conventional topological paradigms. Here we discover experimentally that the nonsymmorphic p4g acoustic metacrystals host a symmetry-protected hierarchy of topological multipoles: the lowest band gap has a quantized Wannier dipole and can mimic the quantum spin Hall effect, whereas the second band gap exhibits quadrupole topology with anomalous Wannier bands. Such a topological hierarchy allows us to observe experimentally distinct, multiplexed topological phenomena and to reveal a topological transition triggered by the geometry transition from the p4g group to the C4v group, which demonstrates elegantly the fundamental interplay between symmetry and topology. Our study demonstrates that classical systems with controllable geometry can serve as powerful simulators for the discovery of novel topological states of matter and their phase transitions.

15.
J Adolesc Health ; 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31974015

RESUMO

PURPOSE: This study was designed to examine the extent to which parents' allostatic load (AL) and adolescents' perceived discrimination are interrelated in the prediction of adolescents' AL among rural-to-urban migrants in China, as well as the possible buffering role of social support. METHODS: Multi-informant data were collected in this study. A total of 158 rural-to-urban migrant adolescents (Meanage = 11.62 years) and one of each of their parents (Meanage = 39.84 years) were recruited from the suburbs of Beijing, China. Both adolescents' and parents' AL scores were based on 10 physiological indices. Migrant adolescents were asked to report their perceived discrimination and social support. RESULTS: Parents' AL was significantly positively related to adolescents' AL. The relationship between parents' and adolescents' AL was stronger among adolescents reporting higher perceived discrimination than among those reporting lower. Social support moderated the adverse effects of parents' AL and perceived discrimination on adolescents' AL. Specifically, among adolescents reporting higher social support, the relationships between parents' and adolescents' AL were not significant for those with either high or low perceived discrimination. However, among adolescents reporting lower social support, the positive association was significant for those with high perceived discrimination but not for those with low perceived discrimination. CONCLUSIONS: Parents' AL was a strong predictor of migrant adolescents' AL, and perceived discrimination acted as a catalyst to increase the association. The relationships of parental AL and perceived discrimination with AL were not significant for adolescents who received high social support.

16.
J Hazard Mater ; 386: 121655, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31780295

RESUMO

Terrestrial fungi, especially arbuscular mycorrhizal (AM) fungi, enhance heavy metal sequestration and promote ecosystem restoration. However, their ecological functions were historically overlooked in discussions regarding water quality. As an AM fungi-derived stable soil protein fraction, glomalin-related soil protein (GRSP) may provide insights into the ecological functions of AM fungi associated with water quality in coastal ecosystems. Here, we first assessed the metal-loading dynamics and ecological functions of GRSP transported into aquatic ecosystems, characterized the composition characteristics, and revealed the mechanisms underlying Cu and Cd sequestration. Combining in situ sampling and in vitro cultures, we found that the composition characteristics of GRSP were significantly affected by the element and mineral composition of sediments. In situ, GRSP-bound Cu and Cd contributed 18.91-22.03% of the total Cu and 2.27-6.37% of the total Cd. Functional group ligands and ion exchange were the principal mechanisms of Cu binding by GRSP, while Cd binding was dominated by functional group ligands. During the in vitro experiment, GRSP sequestered large amounts of Cu and Cd and formed stable complexes, while further dialysis only released 25.74 ±â€¯3.85% and 33.53 ±â€¯3.62% of GRSP-bound Cu and Cd, respectively.

17.
J Neurooncol ; 146(1): 163-170, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31823165

RESUMO

PURPOSE: Understanding the molecular landscape of glioblastoma (GBM) is increasingly important in the age of targeted therapy. O-6-Methylguanine-DNA methyltransferase (MGMT) promoter methylation and EGFR amplification are markers that may play a role in prognostication, treatment, and/or clinical trial eligibility. Quantification of MGMT and EGFR protein expression may offer an alternative strategy towards understanding GBM. Here, we quantify baseline expression of MGMT and EGFR protein in newly diagnosed GBM samples using mass spectrometry. We correlate findings with MGMT methylation and EGFR amplification statuses and survival. METHODS: We retrospectively identified adult patients with newly diagnosed resected GBM. MGMT and EGFR protein expression were quantified using a selected reaction monitoring mass spectrometry assay. Protein levels were correlated with MGMT methylation and EGFR amplification and survival data. RESULTS: We found a statistically significant association between MGMT protein expression and promoter methylation status (p = 0.02) as well as between EGFR protein expression and EGFR amplification (p < 0.0001). EGFR protein expression and amplification were more tightly associated than MGMT protein expression and methylation. Only MGMT promoter methylation was statistically significantly associated with progression-free and overall survival. CONCLUSIONS: Unlike EGFR protein expression and EGFR amplification which are strongly associated, only a weak association was seen between MGMT protein expression and promoter methylation. Quantification of MGMT protein expression was inferior to MGMT methylation for prognostication in GBM. Discordance was observed between EGFR amplification and EGFR protein expression; additional study is warranted to determine whether EGFR protein expression is a better biomarker than EGFR amplification for clinical decisions and trial enrollment.

18.
Adv Healthc Mater ; 9(1): e1901187, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31800164

RESUMO

Highly efficient and stimulus-responsive nanomedicines for cancer treatment are currently receiving tremendous attention. In this study, an acid-triggered charge-reversible graphene-based all-in-one nanocomplex is appropriately designed by surface modification with multilayer polymers and simultaneous co-transportation of photosensitizer indocyanine green (ICG) and oligonucleotide inhibitor of miR-21 (miR-21i) to achieve highly efficient genetic phototherapy in a controlled manner. The nanocomplex (denoted as GPCP/miR-21i/ICG) effectively protects miR-21i from degradation and exhibits excellent photothermal/photochemical reactive oxygen species (ROS) generation as well as fluorescence imaging ability. The cargoes ICG and miR-21i can significantly be released at acidic pH compared with normal physiological medium and escaped from endosomes/lysosomes due to the acid-triggered charge reversal effect. Typically, the released miR-21i downregulate the endogenous miR-21 and result in the upregulation of the target proteins PTEN and Bax, thus increasing the phototherapeutic efficiency of ICG. High in vivo anticancer efficiency against the MDA-MB-231 triple-negative breast cancer (TNBC) model is obtained due to the combination of genetic regulation of miR-21i and the photokilling effect of ICG. This work highlights the great potential of this smart nanocomplex as an attractive modality of gene-photo combined treatment of cancer, especially for intractable TNBC.

19.
Genes Genomics ; 42(1): 25-39, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677128

RESUMO

BACKGROUND: Both photosynthetic pigments and chloroplasts in plant leaf cells play an important role in deciding on the photosynthetic capacity and efficiency in plants. Systematical investigating the regulatory mechanism of chloroplast development and chlorophyll (Chl) content variation is necessary for clarifying the photosynthesis mechanism for crops. OBJECTIVE: This study aims to explore the critical regulatory mechanism of leaf color mutation in a yellow-green leaf sesame mutant Siyl-1. METHODS: We performed the genetic analysis of the yellow-green leaf color mutation using the F2 population of the mutant Siyl-1. We compared the morphological structure of the chloroplasts, chlorophyll content of the three genotypes of the mutant F2 progeny. We performed the two-dimensional gel electrophoresis (2-DE) and compared the protein expression variation between the mutant progeny and the wild type. RESULTS: Genetic analysis indicated that there were 3 phenotypes of the F2 population of the mutant Siyl-1, i.e., YY type with light-yellow leaf color (lethal); Yy type with yellow-green leaf color, and yy type with normal green leaf color. The yellow-green mutation was controlled by an incompletely dominant nuclear gene, Siyl-1. Compared with the wild genotype, the chloroplast number and the morphological structure in YY and Yy mutant lines varied evidently. The chlorophyll content also significantly decreased (P < 0.05). The 2-DE comparison showed that there were 98 differentially expressed proteins (DEPs) among YY, Yy, and yy lines. All the 98 DEPs were classified into 5 functional groups. Of which 82.7% DEPs proteins belonged to the photosynthesis and energy metabolism group. CONCLUSION: The results revealed the genetic character of yellow-green leaf color mutant Siyl-1. 98 DEPs were found in YY and Yy mutant compared with the wild genotype. The regulation pathway related with the yellow leaf trait mutation in sesame was analyzed for the first time. The findings supplied the basic theoretical and gene basis for leaf color and chloroplast development mechanism in sesame.

20.
Adv Mater ; 32(4): e1904876, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31697001

RESUMO

The shuttling behavior and sluggish conversion kinetics of the intermediate lithium polysulfides (LiPSs) represent the main obstructions to the practical application of lithium-sulfur (Li-S) batteries. Herein, an anion-deficient design of antimony selenide (Sb2 Se3- x ) is developed to establish a multifunctional LiPS barrier toward the inhibition of polysulfide shuttling and enhancement of battery performance. The defect chemistry in the as-developed Sb2 Se3- x promotes the intrinsic conductivity, strengthens the chemical affinity to LiPSs, and catalyzes the sulfur electrochemical conversion, which are verified by a series of computational and experimental results. Attributed to these unique superiorities, the obtained LiPS barrier efficiently promotes and stabilizes the sulfur electrochemistry, thus enabling excellent Li-S battery performance, e.g., outstanding cyclability over 500 cycles at 1.0 C with a minimum capacity fading rate of 0.027% per cycle, a superb rate capability up to 8.0 C, and a high areal capacity of 7.46 mAh cm-2 under raised sulfur loading. This work offers a defect engineering strategy toward fast and durable sulfur electrochemistry, holding great promise in developing practically viable Li-S batteries as well as enlightening the material design of related energy storage and conversion systems.

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