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1.
Rice (N Y) ; 17(1): 28, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38622442

RESUMO

Preharvest sprouting (PHS) is an undesirable trait that decreases yield and quality in rice production. Understanding the genes and regulatory mechanisms underlying PHS is of great significance for breeding PHS-resistant rice. In this study, we identified a mutant, preharvest sprouting 39 (phs39), that exhibited an obvious PHS phenotype in the field. MutMap+ analysis and transgenic experiments demonstrated that OsAAH, which encodes allantoate amidohydrolase, is the causal gene of phs39 and is essential for PHS resistance. OsAAH was highly expressed in roots and leaves at the heading stage and gradually increased and then weakly declined in the seed developmental stage. OsAAH protein was localized to the endoplasmic reticulum, with a function of hydrolyzing allantoate in vitro. Disruption of OsAAH increased the levels of ureides (allantoate and allantoin) and activated the tricarboxylic acid (TCA) cycle, and thus increased energy levels in developing seeds. Additionally, the disruption of OsAAH significantly increased asparagine, arginine, and lysine levels, decreased tryptophan levels, and decreased levels of indole-3-acetic acid (IAA) and abscisic acid (ABA). Our findings revealed that the OsAAH of ureide catabolism is involved in the regulation of rice PHS via energy and hormone metabolisms, which will help to facilitate the breeding of rice PHS-resistant varieties.

2.
BMC Public Health ; 21(1): 1135, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-34120600

RESUMO

BACKGROUND: Antenatal care (ANC) played a crucial role in ensuring maternal and child safety and reducing the risk of complications, disability, and death in mothers and their infants. The objective of this study was to evaluate the current status of ANC emphasizing the number, timing, and content of examinations on a national scale. METHODS: The data was collected from maternal and newborn's health monitoring system at 8 provinces in China. After ethical approval, all pregnant women registered in the system at their first prenatal care visit, we included 49,084 pregnant women who had delivered between January 1, 2018 and December 31, 2018. Descriptive statistics of all study variables were calculated proportions and chi-square for categorical variables. RESULTS: Of the 49,084 women included in this study, the mean number of ANC visits was 6.95 ± 3.45. By percentage, 78.79% women received ANC examinations at least five times, 39.93% of the women received ANC examinations at least eight times and 16.66% of the women received ANC examinations at least 11 times. The proportion of first ANC examination in first trimester was 61.87%. The percentage of normative ANC examinations and the percentage of qualified ANC examinations were 30.98 and 8.03% respectively. Only 49.40% of the total women received all six kinds of examination items in first ANC examination: 91.47% received a blood test, 91.62% received a urine test, 81.56% received a liver function examination, 80.52% received a renal function examination, 79.07% received a blood glucose test, and 86.66% received a HIV/HBV/syphilis tests. 50.85% women received the first ANC examination in maternal and child health care (MCH) institutions, 14.07% in a general hospital, 18.83% in a township hospital, 13.15% in a community health services center, and 3.08% in an unspecified place. The proportion of women who received each of the ANC examination items in community health services center was the highest, but that in the MCH institutions was the lowest. CONCLUSIONS: There is a big difference between the results of this study and the data in official reports, this study found the current status of antenatal care is not optimal in China, findings from this study suggest that the systematization, continuity and quality of ANC examinations need to be improved.


Assuntos
Cuidado Pré-Natal , Sífilis , Criança , China/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Primeiro Trimestre da Gravidez , Gestantes
3.
J Hazard Mater ; 398: 122854, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32504958

RESUMO

A coumarin-based fluorescent molecularly imprinted poly (ionic liquid) (FL-MIPIL) was prepared using a new coumarin-based alkenyl fluorescent ionic liquid (coumarin-FL-IL) as the functional monomer, IL [V2C4(mim)2][(PF6)2] and ethyleneglycol dimethacrylate as the cross-linkers, and 4-NP as the template molecule. The absolute quantum yields of coumarin-FL-IL and FL-MIPIL were 7.26 % and 30.66 %, respectively. As a result of the electron transfer between coumarin-FL-IL which contains amino groups and 4-NP bearing hydroxyl groups, FL-MIPIL fluorescence was effectively quenched by 4-NP. The prepared FL-MIPIL sensor can rapidly respond to 4-NP within 60 s. The FL-MIPIL sensor had good linear response to 4-NP from 0.001-7.5 µM and low detection limit of 0.5 nM (S/N = 3). The FL-MIPIL sensor exhibited high sensitivity and good selectivity for 4-NP. The outstanding performance of FL-MIPIL could be ascribed to high fluorescence intensity of FL-MIPIL without matrixes and more interactions between FL-MIPIL and 4-NP. The FL-MIPIL sensor has successfully applied to the determination of 4-NP in lake, rain and waste water samples, river sediment, soil and urine samples.


Assuntos
Líquidos Iônicos , Impressão Molecular , Cumarínicos , Nitrofenóis
4.
J Hazard Mater ; 151(1): 58-64, 2008 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-17597291

RESUMO

In this paper, a system of flow injection (FI) capillary microextraction (CME) on line coupled with inductively plasma mass spectrometry (ICP-MS) was proposed for simultaneous separation and speciation of inorganic As(III)/As(V) and Cr(III)/Cr(VI) in natural waters. Ordered mesoporous Al2O3 coating was prepared by sol-gel technology and used as CME coating material. Various experimental parameters affecting the capillary microextraction of inorganic arsenic and chromium species have been investigated and optimized. Under the optimized conditions, the limits of detection were 0.7 and 18 ng L(-1) for As(V) and Cr(VI), 3.4 and 74 ng L(-1) for As(III) and Cr(III), respectively, with an enrichment factor of 5 and a sampling frequency of 8h(-1). The relative standard deviations (R.S.D.) were 3.1, 4.0, 2.8 and 3.9% (C=1 ng mL(-1), n=7) for As(V), As(III), Cr(VI) and Cr(III), respectively. The proposed method was successfully applied for the analysis of inorganic arsenic and chromium species in mineral water, tap water and lake water with the recovery of 94-105%. In order to verify the accuracy of the method, two certified reference of GSBZ50027-94 and GSBZ50004-88 water samples were analyzed and the results obtained were in good agreement with the certified values. The ordered mesoporous Al2O3 coated capillary showed an excellent solvent and thermal stability and could be re-used for more than 30 times without decreasing extraction efficiency.


Assuntos
Óxido de Alumínio/química , Arsênio/isolamento & purificação , Cromo/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Arsênio/química , Cromo/química , Água Doce/análise , Concentração de Íons de Hidrogênio , Íons/química , Espectrometria de Massas , Águas Minerais/análise , Espectrofotometria Atômica , Poluentes Químicos da Água/química
5.
J Mass Spectrom ; 42(4): 467-75, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17256811

RESUMO

In this work, an ordered mesoporous titania film was introduced to coat a capillary by means of sol-gel technique. Sol-gel titania coating was developed for the preconcentration/separation of trace V, Cr and Cu by capillary microextraction (CME), and the adsorbed analytes were eluted for electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) detection. By immobilizing sol-gel titania on the inner surface of a fused-silica microextraction capillary, the sol-gel titania coating was prepared easily. Its adsorption properties, stability and the factors affecting the adsorption behaviors of V, Cr and Cu were investigated in detail. At pH range of 7 to 9, the titania-coated capillary (50 cm x 0.25 mm) is selective towards V, Cr and Cu, and the target analytes could be desorbed quantitatively with 50 microl of 1.0 mol l(-1) HNO3 at the rate of 0.05 ml min(-1). With a consumption of 2 ml sample solution, an enrichment factor of 33.3, and a detection limit (3 s) of 1.1 pg ml(-1) (10.5 fg) for V; 3.3 pg ml(-1) (33.0 fg) for Cr and 6.3 pg ml(-1) (63.1 fg) for Cu respectively were obtained. The precisions Relative Standard Deviations (RSDs) for nine replicate measurements of 1 ng ml(-1) V, Cr and Cu were 3.4, 5.1 and 6.4%, respectively. The proposed method has been applied to the determination of V, Cr and Cu in human urine and lake water, and the recoveries for these elements were 89.2 approximately 105%. The developed method was also applied to the determination of the target elements in NIES No. 10-a (rice flour-unpolished) and NIES No. 9 (sargasso) certified reference materials, and the results found are in good agreement with the certified values.


Assuntos
Cromo/análise , Cobre/análise , Titânio/química , Vanádio/análise , Poluentes Químicos da Água/análise , Adsorção , Cromo/urina , Cobre/urina , Água Doce/química , Humanos , Concentração de Íons de Hidrogênio , Espectrometria de Massas/métodos , Transição de Fase , Porosidade , Padrões de Referência , Soluções , Vanádio/urina
6.
Anal Chim Acta ; 572(1): 55-62, 2006 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-17723461

RESUMO

In this paper, an ordered mesoporous alumina coating was prepared and applied to capillary microextraction (CME) of trace Co, Ni and Cd for the first time. The coated capillary was used for on-line coupling CME with inductively plasma mass spectrometry (ICP-MS) for the determination of trace metals of Co, Ni and Cd. The porous structure of Al2O3 coating was examined by SEM and TEM. The effects of the extraction parameters including pH, sample flow rate and volume, elution solution and interfering ions on the recovery of analytes have been investigated and optimized. Under the optimized conditions, the limits of detection were 0.33, 1.5 and 1.4 ng L(-1) for Co, Ni and Cd, respectively, with a preconcentration factor of 10 times. The precisions for all investigated elements were 2.7, 4.1 and 2.5% (c=0.05 ng L(-1), n=7), for Co, Ni and Cd, respectively, and the sample frequency was 8 h(-1). The proposed method was successfully applied for the analysis of trace metals in water, rice and urine samples with the recovery of 94-105%. In order to validate the proposed method, two certified reference materials of GBW 0913 human urine and NIES No.10-b rice flour were analyzed, and the determination values are in good agreement with the certified values. The ordered mesoporous Al2O3 coated capillary can be used more than 20 times without decreasing the extraction efficiency.

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