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1.
Proc Natl Acad Sci U S A ; 120(15): e2212468120, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37011215

RESUMO

Soybean (Glycine max) morphogenesis and flowering time are accurately regulated by photoperiod, which determine the yield potential and limit soybean cultivars to a narrow latitudinal range. The E3 and E4 genes, which encode phytochrome A photoreceptors in soybean, promote the expression of the legume-specific flowering repressor E1 to delay floral transition under long-day (LD) conditions. However, the underlying molecular mechanism remains unclear. Here, we show that the diurnal expression pattern of GmEID1 is opposite to that of E1 and targeted mutations in the GmEID1 gene delay soybean flowering regardless of daylength. GmEID1 interacts with J, a key component of circadian Evening Complex (EC), to inhibit E1 transcription. Photoactivated E3/E4 interacts with GmEID1 to inhibit GmEID1-J interaction, promoting J degradation resulting in a negative correlation between daylength and the level of J protein. Notably, targeted mutations in GmEID1 improved soybean adaptability by enhancing yield per plant up to 55.3% compared to WT in field trials performed in a broad latitudinal span of more than 24°. Together, this study reveals a unique mechanism in which E3/E4-GmEID1-EC module controls flowering time and provides an effective strategy to improve soybean adaptability and production for molecular breeding.


Assuntos
Flores , Glycine max , Glycine max/genética , Glycine max/metabolismo , Flores/genética , Flores/metabolismo , Fotoperíodo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
J Colloid Interface Sci ; 629(Pt A): 136-143, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36063631

RESUMO

Carboxylic acid is one of the most crucial and widely used organic chemicals in daily human life activities. Hence preparation of this important chemical was performed under the application of the highly selective photo-catalysts through oxidation of alcohols to carboxylic acids. Herein, we have designed and disclosed a binary NH2-MIL-125(Ti)/ NaBr) catalyst system to realize the effective transformation of alcohols into carboxylic acids under visible light irradiation. Hence, derivatives of benzyl alcohol containing either electron withdrawing and donating groups as well as aliphatic primary alcohols were effectively converted into the corresponding carboxylic acids. Based on our findings, NH2-MIL-125(Ti) based photocatalytic system has shown efficient and highly selective activities for oxidation of alcohol especially the in-situ conversion of co-catalyst NaBr into the corresponding free radical can enhance the alcohol oxidation performance of the catalytic system.


Assuntos
Estruturas Metalorgânicas , Humanos , Catálise , Oxirredução , Álcoois Benzílicos , Ácidos Carboxílicos
3.
Artigo em Inglês | MEDLINE | ID: mdl-37859316

RESUMO

BACKGROUND AND AIM: Nonalcoholic fatty liver disease (NAFLD) is not only the top cause of liver diseases but also a hepatic-correlated metabolic syndrome. This study performed untargeted metabolomics analysis of NAFLD hamsters to identify the key metabolites to discriminate different stages of NAFLD. METHODS: Hamsters were fed a high-fat diet (HFD) to establish the NAFLD model with different stages (six weeks named as the NAFLD1 group and twelve weeks as the NAFLD2 group, respectively). Those liver samples were analyzed by untargeted metabolomics (UM) analysis to investigate metabolic changes and metabolites to discriminate different stages of NAFLD. RESULTS: The significant liver weight gain in NAFLD hamsters was observed, accompanied by significantly increased levels of serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), alanine aminotransferase (ALT), and aspartate aminotransferase (AST). Moreover, the levels of TG, LDL-C, ALT, and AST were significantly higher in the NAFLD2 group than in the NAFLD1 group. The UM analysis also revealed the metabolic changes; 27 differently expressed metabolites were detected between the NAFLD2 and NAFLD1 groups. More importantly, the levels of N-methylalanine, allantoin, glucose, and glutamylvaline were found to be significantly different between any two groups (control, NAFLD2 and NAFLD1). Receiver operating characteristic curve (ROC) curve results also showed that these four metabolites are able to distinguish control, NAFLD1 and NAFLD2 groups. CONCLUSION: This study indicated that the process of NAFLD in hamsters is accompanied by different metabolite changes, and these key differently expressed metabolites may be valuable diagnostic biomarkers and responses to therapeutic interventions.

4.
Nat Commun ; 14(1): 6813, 2023 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884530

RESUMO

Shading in combination with extended photoperiods can cause exaggerated stem elongation (ESE) in soybean, leading to lodging and reduced yields when planted at high-density in high-latitude regions. However, the genetic basis of plant height in adaptation to these regions remains unclear. Here, through a genome-wide association study, we identify a plant height regulating gene on chromosome 13 (PH13) encoding a WD40 protein with three main haplotypes in natural populations. We find that an insertion of a Ty1/Copia-like retrotransposon in the haplotype 3 leads to a truncated PH13H3 with reduced interaction with GmCOP1s, resulting in accumulation of STF1/2, and reduced plant height. In addition, PH13H3 allele has been strongly selected for genetic improvement at high latitudes. Deletion of both PH13 and its paralogue PHP can prevent shade-induced ESE and allow high-density planting. This study provides insights into the mechanism of shade-resistance and offers potential solutions for breeding high-yielding soybean cultivar for high-latitude regions.


Assuntos
Estudo de Associação Genômica Ampla , Glycine max , Glycine max/genética , Melhoramento Vegetal , Fenótipo , Retroelementos
5.
Gland Surg ; 10(4): 1460-1469, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33968697

RESUMO

BACKGROUND: This study examined the effects of different ultrasound imaging technologies in the identification and prediction of axillary lymph node metastasis of breast cancer. It also investigated the relationship between human papilloma virus (HPV) infection and axillary lymph node metastasis. METHODS: Eighty-five female patients diagnosed with breast masses participated in this study. Each patient underwent a conventional ultrasound, ultrasonic elastography, and virtual touch tissue imaging quantification (VTIQ). The differential diagnosis efficiency of a conventional ultrasound, ultrasound elastography, VTIQ, and ultrasound elastography combined with VTIQ technology was compared with a pathological diagnosis, which represents the gold standard. 85 axillary lymph node tissues and 25 normal breast tissues were used to detect HPV positive infection rate differences in different tissues. RESULTS: The results showed that metastatic lymph nodes and reactive lymph node hyperplasia accounted for 54.12% and 45.88% of the 85 axillary lymph nodes of breast cancer, respectively. The conventional ultrasound, ultrasound elastography, and VTIQ scores of metastatic lymph nodes were significantly higher than those of reactive lymph node hyperplasia (P<0.05). The diagnostic sensitivity (Se) (91.30%), specificity (Sp) (92.31%), accuracy (Ac) (91.76%), positive predictive value (PPV) (93.33%), and negative predictive value (NPV) (90.00%) of ultrasound elastography combined with VTIQ technology were the highest among the diagnostic efficiency test results of different computer ultrasound imaging technologies. The positive infection rate of HPV in metastatic lymph node tissues was significantly higher than that in reactive lymph node hyperplasia and normal breast tissues (P<0.05). CONCLUSIONS: Combining ultrasound elastography with VTIQ technology has high value in the differential diagnosis of axillary lymph nodes of breast cancer. Further, it appears that HPV infection may have an etiological role in lymph node metastasis in breast cancer patients.

6.
Gland Surg ; 10(6): 1980-1988, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34268082

RESUMO

BACKGROUND: At present, most ultrasound (US) studies on triple negative breast cancer (TNBC) are limited to conventional US features, so it is necessary to develop new joint diagnostic methods. The study aims to explore the values of conventional US and shear wave elastography (SWE) in differential diagnoses of TNBC and non-TNBC. METHODS: A total of 120 breast cancer (BC) patients involving 120 lesions that were pathologically verified were retrospectively analyzed in this study. All participants had received both conventional US and SWE before surgery. Meanwhile, the participants were divided into a TNBC group or a non-TNBC group according to their immunohistochemical (IHC) results. The differences between the conventional US features (including lesion shape, growth location, margin, boundary, internal echo, micro-calcification, posterior echo, and internal blood supply) and the SWE image features [including mean lesion hardness (Emean), maximum (Emax), minimum (Emin), standard deviation (SD), and ratio to normal gland (Eratio)] of 2 groups were compared. The receiver operating characteristic (ROC) curve of the diagnosed lesion was calculated by the area under the curve (AUC). RESULTS: According to the findings of conventional US, the TNBC group mostly manifested as a micro-lobulated margin, with a clear boundary and no internal micro-calcification; the non-TNBC group mainly manifested as marginal angulation or burr, and hyper-echo halo in the boundary, accompanied with internal micro-calcification, and the difference was statistically significant (P<0.05); the internal thrombolysis in myocardial infarction (TIMI) and resistance index between the TNBC group and non-TNBC group were similar, and the differences were not statistically significant (P>0.05). The findings of SWE were as follows: differences in Emax, Emean, and Eratio values between 2 groups were statistically significant (P<0.05); and the areas under the ROC curve (AUC) of these three in diagnosing the lesions were 0.811, 0.781 and 0.770, respectively. CONCLUSIONS: Conventional US combined with SWE can comprehensively analyze the morphological, blood supply, and hardness features of breast lesions, and provide more reliable information for the differential diagnosis between TNBC and non-TNBC.

7.
RSC Adv ; 11(23): 14140-14147, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35423947

RESUMO

A highly efficient pretreatment strategy using ethylene glycol with dilute sulfuric acid was developed for the fractionation of lignocellulose. The pretreatment behaviors were related to the composition analysis and structure of the samples analyzed by SEM, XRD, FTIR and 2D HSQC NMR, resulting in 80.3% delignification and 84.7% retention of cellulose under the selected conditions (120 °C, 60 min, and 0.6 wt% H2SO4 (w/w)). The enzymatic hydrolysis sugar yield significantly increased from 24.1 to 70.6% (3 FPU g-1), which displayed immense improvement compared with untreated corn stover (24.1%), nearly 3-fold higher than its untreated counterparts. Besides, the regenerated lignin could be fitted to valorize renewable aromatic chemicals and alkane fuels. The present study shows that the pretreatment is a simple, efficient and promising process for corn stover biorefinery.

8.
ACS Appl Mater Interfaces ; 13(21): 24966-24975, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34008944

RESUMO

The development of transition metal-based heterogeneous catalysts for economical and efficient synthesis of secondary imines remains both desirable and challenging. Herein, for the first time, we present two kinds of Rh nanoparticle anchored uniform spherical COF heterogeneous catalysts with well-defined crystalline structures for the effective one-pot tandem reductive amination of aldehydes on a gram scale. This reaction is carried out using ammonia as a nitrogen source and hydrogen gas as the source of hydrogen, which is not only an atom-economical but also an environmentally friendly process for the selective production of secondary imines. In particular, in the presence of the better-designed Rh nanoparticles anchored COF2 catalyst, the starting material aldehydes could be fully converted (99% conversion), and 95% selectivity of N-benzylidene(phenyl)methanamine is obtained under mild reaction conditions (2 MPa of H2 and 90 °C). Additionally, the Rh/COF2 catalyst is also applied to a variety of substituted aromatic aldehyde compounds, manifesting good yields in corresponding secondary imines. This work not only expands the COF family but also offers economical and effective access to acquire various aromatic amine targets, especially secondary imines.

9.
J Hazard Mater ; 416: 125789, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-33894438

RESUMO

Mustard gas has been used as a chemical warfare agent for a century, and is the most likely chemical weapon used in wars or by terrorists. Thus, it is important to develop a facile, rapid and highly selective method for the detection of mustard gas. In this paper, two fluorescent probe molecules, 4-mercaptocoumarins, have been developed for rapid and sensitive detections of SM and its analogues (CEES and NH1) in both solutions and gas phase. The sensing reaction is a nucleophilic addition at three-membered hetercyclic sulfonium/ammonium formed from SM, CEES/NH1 in ethanol. Two fluorescent probes (4-mercaptocoumarins, ArSH) in ethanol deprotonate to form thiophenol anions (ArS-) resulting from their low pKa values (3.2-3.4), and the nucleophilic addition of the anion ArS- generates the corresponding thioethers, giving a turn-on fluorescence response. The thiophenol anion can fast sense SM, CEES and NH1 (within 1-4 min) with high sensitivity (~nM level) at 60 °C, and high selectivity through adding a tertiary amine, and two probes exhibit excellent chemical and photostability in detection systems. Furthermore, a facile test strip with the sensor was fabricated for the detection of CEES vapor with rapid response (3 min), high sensitivity (9 ppb) and high selectivity.


Assuntos
Substâncias para a Guerra Química , Gás de Mostarda , Corantes Fluorescentes , Gás de Mostarda/análise
10.
Molecules ; 15(4): 2872-85, 2010 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-20428085

RESUMO

Neutral starch microspheres (NSMs) were synthesized by an inverse microemulsion technology with epichlorohydrin as a crosslinker and soluble starch as starting material. Anionic starch microspheres (ASMs) were prepared from NSMs by the secondary polymerization with chloroacetic acid as the anionic etherifying agent. Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and laser diffraction particle size analyzer were used to characterize the anionic starch microspheres. The results showed that structure of the microspheres was compact and the hardness of microspheres was great, and the average diameter of the product was about 75 microm. The anionic starch microspheres (ASMs) were used to adsorb methylene blue (MB) from aqueous solution. Effects of adsorption time, initial concentration of MB, and temperature on the adsorption of MB onto ASMs were studied, and the equilibrium and kinetics of the adsorption process were further investigated. It shows that ASMs can effectively remove MB from the solution. The adsorption equilibrium data correlates well with the Langmuir isotherm model compared with Frendlich isotherem model. The pseudo-first-order and pseudo-second-order kinetic models were applied to test the experimental data. The pseudo-second-order kinetic model provided a better correlation of the experimental data in comparison with the pseudo-first-order model. Temperature variations did not significantly affect the adsorption of MB onto ASMs.


Assuntos
Microesferas , Amido/química , Absorção , Ânions/química , Reagentes de Ligações Cruzadas/química , Emulsões , Epicloroidrina/química , Azul de Metileno/química , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
11.
Org Lett ; 21(23): 9497-9501, 2019 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-31718192

RESUMO

The reaction of hydrazides with triphosgene in the presence of triethylamine is a facile method to construct various oxadiazolones. Utilizing this reaction, a new class of colorimetric and fluorogenic phosgene chemosensors were developed with the BODIPY as fluorophore, five BODIPY-based hydrazides, which exhibited highly effective reactions with phosgene. The mechanism was updated. Finally, the test paper with a hydrazide was fabricated for facile, selective, and visual detection of phosgene gas.

12.
Invest. clín ; 63(2): 147-155, jun. 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1534651

RESUMO

Abstract Although stages T3 and T4 rectal cancer can be reduced to T1 or T2 after neoadjuvant radiochemotherapy, the accuracy of the endorectal ultrasonography (ERUS) for the post-radiochemotherapy evaluation of low rectal cancer has seldom been reported. We aimed to investigate the value of ERUS in the assessment of invasion staging in low rectal cancer with local progression, and the factors affecting its accuracy, after neoadjuvant radiochemotherapy. A total of 114 patients administered with neoadjuvant radiochemotherapy for stages II and III low rectal cancer (local stage T3/T4) from February 2018 to December 2020 were enrolled in the study. The changes in local lesions were evaluated using ERUS before and after radiochemotherapy, and compared with the pathological T staging. The accuracy of post-neoadjuvant radiochemotherapy re-staging examined with ERUS was evaluated, and univariate analysis was used to identify the factors affecting the accuracy. After neoadjuvant radiochemotherapy, the blood flow distribution within the lesion significantly declined (P<0.05), the max length and max thickness of the longitudinal axis of the lesion were reduced (P<0.05), and the uT staging was decreased (P<0.05), when compared with lesions before the treatment. Compared with postoperative pathological T staging, the accuracies of ERUS in T1, T2, T3 and T4 stages were 11.11%, 28.57%, 27.27% and 100%, respectively. Univariate analysis indicated that review time of ERUS, post-operative T staging and Wheeler rectal regression stage were factors affecting the accuracy of ERUS re-staging. ERUS is more accurate for T4 re-staging, follow-up reviewed six weeks after neoadjuvant radiochemotherapy and low regression tumors, with a high application value for the assessment of the efficacy of neoadjuvant radiochemotherapy for low rectal cancer.


Resumen Aunque el cáncer de recto en estadios T3 y T4 se puede reducir a T1 o T2 después de la radioquimioterapia neoadyuvante, rara vez se ha informado la precisión de la ecografía endorrectal (ERUS) para la evaluación posterior a la radioquimioterapia del cáncer de recto inferior. Nuestro objetivo fue investigar el valor de ERUS en la evaluación de la estadificación de la invasión en el cáncer de recto inferior con progresión local, después de la radioquimioterapia neoadyuvante y los factores que afectan su precisión. Se incluyeron en el estudio un total de 114 pacientes a los que se les administró radioquimioterapia neoadyuvante para el cáncer de recto inferior en estadios II y III (estadio local T3/T4), desde febrero de 2018 hasta diciembre de 2020. Los cambios en las lesiones locales se evaluaron mediante ERUS antes y después de la radioquimioterapia y se compararon con la estadificación patológica T. Se evaluó la precisión de la re-estadificación examinada con ERUS, después de la radioquimioterapia neoadyuvante y se utilizó un análisis univariado para identificar los factores que afectan su precisión. Después de la radioquimioterapia neoadyuvante, la distribución del flujo sanguíneo dentro de la lesión disminuyó significativamente (P<0,05), la longitud máxima y el espesor máximo del eje longitudinal de la lesión se redujeron (P<0,05) y la estadificación uT disminuyó (P<0,05), en comparación con las lesiones antes del tratamiento. En comparación con la estadificación T patológica posoperatoria, las precisiones de ERUS en las etapas T1, T2, T3 y T4 fueron del 11,11%, 28,57%, 27,27% y 100%, respectivamente. El análisis univariable indicó que el tiempo de revisión de ERUS, la estadificación T postoperatoria y la etapa de regresión rectal de Wheeler fueron factores que afectaron la precisión de la re-estadificación con ERUS. ERUS es más preciso para la re-estadificación de T4, el seguimiento seis semanas después de la radioquimioterapia neoadyuvante y en tumores de baja regresión, con un alto valor de aplicación para la evaluación de la eficacia de la radioquimioterapia neoadyuvante para el cáncer rectal bajo.

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