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1.
Cancer Sci ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39009033

RESUMO

Austocystin D is a natural compound that induces cytochrome P450 (CYP) monooxygenase-dependent DNA damage and growth inhibition in certain cancer cell lines. Cancer cells exhibiting higher sensitivity to austocystin D often display elevated CYP2J2 expression. However, the essentiality and the role of CYP2J2 for the cytotoxicity of this compound remain unclear. In this study, we demonstrate that CYP2J2 depletion alleviates austocystin D sensitivity and DNA damage induction, while CYP2J2 overexpression enhances them. Moreover, the investigation into genes involved in austocystin D cytotoxicity identified POR and PGRMC1, positive regulators for CYP activity, and KAT7, a histone acetyltransferase. Through genetic manipulation and analysis of multiomics data, we elucidated a role for KAT7 in CYP2J2 transcriptional regulation. These findings strongly suggest that CYP2J2 is crucial for austocystin D metabolism and its subsequent cytotoxic effects. The potential use of austocystin D as a therapeutic prodrug is underscored, particularly in cancers where elevated CYP2J2 expression serves as a biomarker.

2.
Small ; : e2309570, 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39155494

RESUMO

The escalating demand for portable near-infrared (NIR) light sources has posed a formidable challenge to the development of NIR phosphors characterized by high efficiency and exceptional thermal stability. Taking inspiration from the chemical unit co-substitution strategy, high-performance tunable (Lu3- xCax)(Ga5- xGex)O12:6%Cr3+ (x = 0-3) phosphors are designed with an emission center from 704 to 780 nm and a broadest full width at half maximum (FWHM) of up to 172 nm by introducing Ca2+ and Ge4+ ions into the garnet structure. In particular, Lu3Ga5O12:6%Cr3+ demonstrates an anti-thermal quenching phenomenon (I423K = 113.1%). Compared to Lu3Ga5O12:6%Cr3+, Lu2CaGa4GeO12:6%Cr3+ exhibits significantly improved FWHM and IQE by 108 nm and 25.5%, respectively, while maintaining good thermal stability (I423K = 80.4%). Finally, Lu2CaGa4GeO12:6%Cr3+ phosphor is combined with a 465 nm blue LED chip to fabricate NIR LED devices, exhibiting a NIR electroluminescence efficiency of 13.31%@100 mA and demonstrating successful applications in nocturnal illumination and biomedical imaging technology. This work offers a fresh perspective on the design of highly efficient NIR garnet phosphors.

3.
Small ; 20(21): e2308783, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38105423

RESUMO

The low power conversion efficiency (PCE) of hole transport materials (HTM) - free carbon-based perovskite solar cells (C-PSCs) poses a challenge. Here, a novel 2D Eu-TCPP MOF (TCPP; [tetrakis (4-carboxyphenyl) porphyrin]) sandwiched between the perovskite layer and the carbon electrode is used to realize an effective and stable HTM-free C-PSCs. Relying on the synergistic effect of both the metal-free TCPP ligand with a unique absorption spectrum and hydrophobicity and the EuO4(OH)2 chain in the Eu-TCPP MOF, defects are remarkably suppressed and light-harvesting capability is significantly boosted. Energy band alignment is achieved after Eu-TCPP MOF treatment, promoting hole collection. Förster resonance energy transfer results in improved light utilization and protects the perovskite from decomposition. As a result, the HTM-free C-PSCs with Eu-TCPP MOF reach a champion PCE of 18.13%. In addition, the unencapsulated device demonstrates outstanding thermal stability and UV resistance and keeps 80.6% of its initial PCE after 5500 h in a high-humidity environment (65%-85% RH).

4.
Chembiochem ; 25(15): e202400346, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38775416

RESUMO

Multi-enzyme cascade catalysis has become an important technique for chemical reactions used in manufacturing and scientific study. In this research, we designed a four-enzyme integrated catalyst and used it to catalyse the deracemization reaction of cyclic chiral amines, where monoamine oxidase (MAO) catalyses the enantioselective oxidation of 1-methyl-1,2,3,4-tetrahydroisoquinoline (MTQ), imine reductase (IRED) catalyses the stereo selective reduction of 1-methyl-3,4-dihydroisoquinoline (MDQ), formate dehydrogenase (FDH) is used for the cyclic regeneration of cofactors, and catalase (CAT) is used for decomposition of oxidative reactions. The four enzymes were immobilized via polydopamine (PDA)-encapsulated dendritic organosilica nanoparticles (DONs) as carriers, resulting in the amphiphilic core-shell catalysts. The hydrophilic PDA shell ensures the dispersion of the catalyst in water, and the hydrophobic DON core creates a microenvironment with the spatial confinement effect of the organic substrate and the preconcentration effect to enhance the stability of the enzymes and the catalytic efficiency. The core-shell structure improves the stability and reusability of the catalyst and rationally arranges the position of different enzymes according to the reaction sequence to improve the cascade catalytic performance and cofactor recovery efficiency.


Assuntos
Aminas , Monoaminoxidase , Polímeros , Aminas/química , Aminas/metabolismo , Monoaminoxidase/metabolismo , Monoaminoxidase/química , Polímeros/química , Polímeros/metabolismo , Formiato Desidrogenases/metabolismo , Formiato Desidrogenases/química , Catalase/química , Catalase/metabolismo , Indóis/química , Indóis/metabolismo , Estereoisomerismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Oxirredução , Nanopartículas/química , Biocatálise , Compostos de Organossilício/química , Oxirredutases/metabolismo , Oxirredutases/química , Catálise
5.
J Org Chem ; 89(7): 4818-4825, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38536102

RESUMO

The enantioselective synthesis of chiral diarylmethanols is highly desirable in synthetic chemistry and the pharmaceutical industry, but it remains challenging, especially in terms of green and sustainable production. Herein, a resin-immobilized palladium acetate catalyst was fabricated with high activity, stability, and reusability in Suzuki cross-coupling reaction of acyl halides with boronic acids, and the coimmobilization of alcohol dehydrogenase and glucose dehydrogenase on resin supports was also conducted for asymmetric bioreduction of diaryl ketones. Experimental results revealed that the physicochemical properties of the resins and the immobilization modes played important roles in affecting their catalytic performances. These two catalysts enabled the construction of a chemoenzymatic cascade for the enantioselective synthesis of a series of chiral diarylmethanols in high yields (83-90%) and enantioselectivities (87-98% ee). In addition, the asymmetric synthesis of the antihistaminic and anticholinergic drugs (S)-neobenodine and (S)-carbinoxamine was also achieved from the chiral diarylmethanol precursors, demonstrating the synthetic utility of the chemoenzymatic cascade.


Assuntos
Álcool Desidrogenase , Paládio , Paládio/química , Estereoisomerismo , Estrutura Molecular , Catálise
6.
Inorg Chem ; 63(1): 812-823, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38109652

RESUMO

Phosphors used in NIR spectroscopy require broadband emission, high external quantum yield, good ability, as well as a tunable spectral range to meet the detection criteria. Two-dimensional copper silicates MCuSi4O10 (M = Ca, Sr, Ba) play an important part in ancient art and technology as synthetic blue pigments. In the recent years, these compounds were reported to show a broad near-infrared emission when excited in the visible region. Inspired by the tunable structure of MCuSi4O10, a series of broadband phosphors Ca1-xSrxCuSi4O10 were designed for realizing continuously tunable NIR emission by a modulated Cu2+ crystal field environment. The emission maximum exhibits a red shift from 915 to 950 nm and the integral intensity enhances as the Sr2+ content varies in the range of 0-0.50, which is led by the lattice expansion and the following weakened crystal field splitting on tetrahedral-coordinated Cu2+. Compared to CaCuSi4O10, the optimized sample Ca0.5Sr0.5CuSi4O10 shows enhanced NIR emission by about 2.0-fold. It exhibits quite a high external quantum efficiency covering the NIR-I and -II regions (λmax = 950 nm, fwhm = 135 nm, EQE = 26.3%) with a strong absorption efficiency (74.7%) and a long excited-state lifetime (134 µs). These solid-solution phosphors (x = 0.0-0.5) show excellent thermal stability and maintain over 50% of the RT intensity at 200 °C. The optimized phosphor was encapsulated with red-light chips to fabricate NIR pc-LED and put into night-vision application. These good properties make these Cu2+-activated NIR phosphors appealing for multiple applications such as nondestructive testing, night version, lasers, and luminescent solar concentrators.

7.
Luminescence ; 39(8): e4858, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39129443

RESUMO

The research outlined a novel approach for creating a sensitive and efficient ratio fluorescent probe for ciprofloxacin (CIP) detection. The method used the biomass materials passionfruit shell and diethylenetriamine as carbon and nitrogen sources, respectively, to prepare blue fluorescent carbon quantum dots (b-CQDs) with an average size of 3.29 nm and a quantum yield of 19.6% by a hydrothermal method. The newly designed b-CQDs/riboflavin ratio fluorescent probe demonstrates a distinct advantage for CIP monitoring, exhibiting a marked increase in fluorescence intensity at 445 nm upon interaction with CIP, while maintaining a stable intensity at 510 nm. In the water system, the I445 nm/I510 nm ratio of the fluorescent probe showed a significant linear relationship with CIP at the concentrations of 0-250 µmol·L-1, and the probe boasts a low detection limit of 0.86 µmol·L-1. The outstanding selectivity, broad detection range, low detection limits, and high quantum yield of the b-CQDs highlight their significant potential in the development of advanced sensing probes for efficient detection of ciprofloxacin, offering promising insights for future sensor technology advancements.


Assuntos
Carbono , Ciprofloxacina , Corantes Fluorescentes , Pontos Quânticos , Pontos Quânticos/química , Ciprofloxacina/análise , Ciprofloxacina/química , Ciprofloxacina/sangue , Corantes Fluorescentes/química , Carbono/química , Espectrometria de Fluorescência , Limite de Detecção
8.
Angew Chem Int Ed Engl ; 63(37): e202407778, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-38871651

RESUMO

Multienzyme cascades (MECs) have gained much attention in synthetic chemistry but remain far from being a reliable synthetic tool. Here we report a four-enzyme cascade comprising a cofactor-independent and a cofactor self-sustaining bienzymatic modules for the enantioselective benzylic C-H amination of arylalkanes, a challenging transformation from bulk chemicals to high value-added chiral amines. The two modules were subsequently optimized by enzyme co-immobilization with microenvironmental tuning, and finally integrated in a gas-liquid segmented flow system, resulting in simultaneous improvements in enzyme performance, mass transfer, system compatibility, and productivity. The flow system enabled continuous C-H amination of arylalkanes (up to 100 mM) utilizing the sole cofactor NADH (0.5 mM) in >90 % conversion, achieving a high space-time yield (STY) of 3.6 g ⋅ L-1 ⋅ h-1, which is a 90-fold increase over the highest value previously reported.


Assuntos
Enzimas Imobilizadas , Aminação , Estereoisomerismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Aminas/química , Alcanos/química , Estrutura Molecular , NAD/química , NAD/metabolismo
9.
Angew Chem Int Ed Engl ; 63(24): e202405310, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38606567

RESUMO

Chiral hybrid metal halides hold great potential as circularly polarized luminescence light sources. Herein, we have obtained two enantiomeric pairs of one-dimensional hybrid chiral manganese(II) chloride single crystals, R/S-(3-methyl piperidine)MnCl3 (R/S-1) and R/S-(3-hydroxy piperidine)MnCl3 (R/S-2), crystallizing in the non-centrosymmetric space group P212121. In comparison to R/S-1, R/S-2 single crystals not only show red emission with near-unity photoluminescence quantum yield (PLQY) and high resistance to thermal quenching but also exhibit circularly polarized luminescence with an asymmetry factor (glum) of 2.5×10-3, which can be attributed to the enhanced crystal rigidity resulting from the hydrogen bonding networks between R/S-(3-hydroxy piperidine) cations and [MnCl6]4- chains. The circularly polarized luminescence activities originate from the asymmetric [MnCl6]4- luminophores induced by N-H⋅⋅⋅Cl hydrogen bonding with R/S-(3-hydroxy piperidine). Moreover, these samples demonstrate great application potential in circularly polarized light-emitting diodes and X-ray scintillators. This work shows a highly efficient photoluminescent Mn-based halide and offers a strategy for designing multifunctional chiral metal halides.

10.
Gut ; 72(5): 855-869, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36690433

RESUMO

BACKGROUND AND AIMS: Current practice on Helicobacter pylori infection mostly focuses on individual-based care in the community, but family-based H. pylori management has recently been suggested as a better strategy for infection control. However, the family-based H. pylori infection status, risk factors and transmission pattern remain to be elucidated. METHODS: From September 2021 to December 2021, 10 735 families (31 098 individuals) were enrolled from 29 of 31 provinces in mainland China to examine family-based H. pylori infection, related factors and transmission pattern. All family members were required to answer questionnaires and test for H. pylori infection. RESULTS: Among all participants, the average individual-based H. pylori infection rate was 40.66%, with 43.45% for adults and 20.55% for children and adolescents. Family-based infection rates ranged from 50.27% to 85.06% among the 29 provinces, with an average rate of 71.21%. In 28.87% (3099/10 735) of enrolled families, there were no infections; the remaining 71.13% (7636/10 735) of families had 1-7 infected members, and in 19.70% (1504/7636), all members were infected. Among 7961 enrolled couples, 33.21% had no infection, but in 22.99%, both were infected. Childhood infection was significantly associated with parental infection. Independent risk factors for household infection were infected family members (eg, five infected members: OR 2.72, 95% CI 1.86 to 4.00), living in highly infected areas (eg, northwest China: OR 1.83, 95% CI 1.57 to 2.13), and large families in a household (eg, family of three: OR 1.97, 95% CI 1.76 to 2.21). However, family members with higher education and income levels (OR 0.85, 95% CI 0.79 to 0.91), using serving spoons or chopsticks, more generations in a household (eg, three generations: OR 0.79, 95% CI 0.68 to 0.92), and who were younger (OR 0.57, 95% CI 0.46 to 0.70) had lower infection rates (p<0.05). CONCLUSION: Familial H. pylori infection rate is high in general household in China. Exposure to infected family members is likely the major source of its spread. These results provide supporting evidence for the strategic changes from H. pylori individual-based treatment to family-based management, and the notion has important clinical and public health implications for infection control and related disease prevention.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Criança , Adulto , Adolescente , Humanos , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/prevenção & controle , Família , Fatores de Risco , China/epidemiologia , Estudos Epidemiológicos , Prevalência
11.
J Org Chem ; 88(11): 7104-7116, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37141629

RESUMO

A photocatalytic chemodivergent reaction for the selectivity formation of C-S and C-N bonds in a controlled manner was proposed. The reaction medium, either neutral or acidic, is critical to dictate the formation of 2-amino-1,3,4-thiadiazoles and 1,2,4-triazole-3-thiones from isothiocyanates and hydrazones. This is a practical protocol to achieve the chemoselectivity under mild and metal-free conditions.

12.
Helicobacter ; 28(3): e12958, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36828668

RESUMO

BACKGROUND: Empiric therapy for Helicobacter pylori infection results in significantly increased antibiotic resistance and decreased eradication efficacy. The genotypic testing of clarithromycin resistance from stool specimens is a promising method for individualized diagnosis and treatment. This study aimed to determine the status of research and application on this method through a systematic review and meta-analysis. METHODS: PubMed, Embase, MEDLINE, and WAN FANG database were searched for relevant literature. The quality of included diagnostic articles was evaluated using the quality Assessment of Diagnostic Accuracy Studies-2 tool. A bivariate random-effect model was conducted to calculate the diagnostic accuracy of genotypic testing of clarithromycin resistance. RESULTS: A total of 16 diagnostic-related were included and analyzed after exclusions. The pooled sensitivity and specificity of diagnostic meta-analysis were 0.93 (95% confidence interval [CI]: 0.90-0.96) and 0.98 (95% CI: 0.93-1.00), respectively. The area under the curve (AUC) of the summary receiver operating characteristic was 0.97 (95% CI: 0.95-0.98). The genotypic testing in stool samples had heterogeneous sensitivity (Q = 37.82, p < .01, I2  = 37.82) and specificity (Q = 60.34, p < .01, I2  = 93.72) in detecting clarithromycin resistance. Purification method, stool sample weight, real-time PCR, and antimicrobial susceptibility testing as reference accounted for the heterogeneity of pooled sensitivity, while patient age, purification method, stool sample weight, and real-time PCR for the heterogeneity of pooled specificity. CONCLUSION: The genotypic testing of clarithromycin resistance from stool specimens is an accurate, convenient, noninvasive, and rapid detection technology, providing a definitive diagnosis of clarithromycin resistance and guiding the rational antibiotic selection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Claritromicina/farmacologia , Claritromicina/uso terapêutico , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Farmacorresistência Bacteriana/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Reação em Cadeia da Polimerase em Tempo Real , Testes de Sensibilidade Microbiana
13.
Helicobacter ; 28(2): e12956, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36752304

RESUMO

BACKGROUND: Helicobacter pylori eradication in penicillin-allergic patients is challenging. The effective regimen is lacking in areas with high antibiotic resistance and tetracycline unavailable. Minocycline, cefuroxime, and full-dose metronidazole are promising drugs. AIMS: To compare the eradication rate, safety, and compliance among three new bismuth quadruple therapies for first-line H. pylori eradication in penicillin-allergic patients. METHODS: This randomized trial was conducted on 450 naive patients with H. pylori infection and penicillin allergy. The 14-day minocycline-metronidazole-containing (minocycline 100 mg twice daily and metronidazole 400 mg four times/day), minocycline-cefuroxime-containing (minocycline 100 mg twice daily and cefuroxime 500 mg twice daily), and cefuroxime-metronidazole-containing (cefuroxime 500 mg twice daily and metronidazole 400 mg four times/day) bismuth quadruple therapies were randomly assigned to the participants. Safety and compliance were assessed within 3 days after eradication. Urea breath test was performed 4-8 weeks after eradication to evaluate outcome. RESULTS: The differences of eradication rates in either intention-to-treat (84.0%, 82.7%, and 23 82.0%, p = .896) or per-protocol (91.7%, 90.9%, and 88.2%, p = .599) analysis among minocycline-metronidazole, minocycline-cefuroxime, and cefuroxime-metronidazole-containing bismuth quadruple therapies were statistically insignificant. The incidence of adverse events (35.1%, 22.6%, and 28.9%) and compliance (90.5%, 91.8%, and 91.9%) were similar. Taste distortion, nausea, and anorexia were more common in metronidazole-containing regimens, and dizziness was more common in minocycline-containing regimens. The allergy was rare (~3%). CONCLUSIONS: The efficacies of three bismuth quadruple therapies containing minocycline, cefuroxime, and full-dose metronidazole (pairwise) for first-line H. pylori eradication in penicillin-allergic patients were similarly satisfactory with relatively good safety and compliance. The study was registered in the Chinese Clinical Trials Registration (ChiCTR1900023702).


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Hipersensibilidade , Humanos , Infecções por Helicobacter/tratamento farmacológico , Penicilinas/efeitos adversos , Bismuto/uso terapêutico , Metronidazol/uso terapêutico , Cefuroxima/farmacologia , Cefuroxima/uso terapêutico , Minociclina/farmacologia , Minociclina/uso terapêutico , Antibacterianos/uso terapêutico , Tetraciclina/uso terapêutico , Adesão à Medicação , Quimioterapia Combinada , Resultado do Tratamento , Amoxicilina/uso terapêutico
14.
Helicobacter ; 28(1): e12935, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36374159

RESUMO

BACKGROUND: Due to general unavailability and common side effects of tetracycline, the clinical application of bismuth quadruple therapy (BQT) is greatly limited. Whether amoxicillin can replace tetracycline in BQT remains unknown. This study aimed to compare the eradication rate, safety and compliance between amoxicillin-containing and tetracycline-containing BQT as a first-line regimen for Helicobacter pylori eradication. METHODS: This randomized trial was conducted on 404 naïve patients for H. pylori eradication. The participants were randomly assigned to 14-day amoxicillin-containing (bismuth potassium citrate 110 mg four times/day, esomeprazole 20 mg twice daily, metronidazole 400 mg four times/day and amoxicillin 500 mg four times/day) and tetracycline-containing (tetracycline 500 mg four times/day and the other three drugs used as above) BQT. Safety and compliance were assessed within 3 days after eradication. Urea breath test was performed 4-8 weeks after eradication to evaluate outcome. RESULTS: As for the eradication rates of amoxicillin-containing and tetracycline-containing BQT, the results of both intention-to-treat and per-protocol analyses showed that the difference rate of the lower limit of 95% confidence interval was above -10.0% (intention-to-treat analysis: 81.7% vs. 83.2%, with a rate difference of -1.5% [-6.3% to 9.3%]; per-protocol analysis: 89.0% vs. 91.6%, -2.6% [-4.1% to 9.3%]). The incidence of adverse events in amoxicillin-containing BQT was significantly lower than tetracycline-containing BQT (29.5% vs. 39.7%). Both groups achieved relatively good compliance (92.0% vs. 89.9%). CONCLUSION: The eradication efficacy of amoxicillin-containing BQT was non-inferior to tetracycline-containing BQT as a first-line regimen for H. pylori eradication with better safety and similar compliance.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Humanos , Amoxicilina/efeitos adversos , Metronidazol/efeitos adversos , Bismuto/efeitos adversos , Esomeprazol/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Antibacterianos/efeitos adversos , Tetraciclina/efeitos adversos , Quimioterapia Combinada
15.
Inorg Chem ; 62(32): 12862-12871, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37527521

RESUMO

Fe3+-doped near-infrared (NIR) phosphors have received a lot of interest because they are nontoxic, inexpensive, and ecologically benign. In this work, Fe3+-activated Li2ZnAO4 (A = Si, Ge) phosphors were synthesized by solid-phase reactions, in which Fe3+ entered the Zn2+ tetrahedral site. When excited by 300 nm UV light, broad NIR emission bands at 750 nm (Li2ZnSiO4: Fe3+) and 777 nm (Li2ZnGeO4: Fe3+) were observed, with internal quantum efficiencies (IQE) of 62.70% (Li2ZnSiO4: Fe3+) and 30.57% (Li2ZnGeO4: Fe3+). The thermal stability was increased from 35.43 to 49.79% at 373 K via cationic regulation. The combination of activation energy, electron-phonon coupling, and Debye temperature explained the improved thermal stability of Li2ZnGeO4: Fe3+ phosphor. Besides, the as-synthesized phosphor demonstrated sensitive and selective Cu2+ ion detection.

16.
Inorg Chem ; 62(35): 14494-14503, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37611183

RESUMO

Realizing ultra-wideband and tunable near-infrared (NIR) emission remains a great challenge in NIR phosphor development. The luminescence of most reported NIR phosphors exhibits a peak wavelength shorter than 1000 nm and the corresponding FWHM is <200 nm. Here, a series of Cr3+-activated Li(Sc,In)(Si,Ge)O4 phosphors with ultra-wideband and tunable NIR-II emission are successfully developed based on the host composition engineering strategy. Significant spectral engineering in the NIR-II region is achieved with a peak wavelength changing from 1110 to 1253 nm. The olivine host structure could provide Cr3+ activator a highly distorted octahedral site with very weak crystal field strength, which results in NIR-II ultra-wideband emission with FWHM > 300 nm. A detailed discussion on the relationship between structural variation, crystal field splitting, and NIR luminescence has been applied. As far as we know, it is the first report about Cr3+ NIR luminescence engineering in such a long wavelength and wide range. The application of these NIR-II phosphors is demonstrated in intensity-based luminescent thermometry with a relative sensitivity of >2.0% K-1 in the physiological temperature range.

17.
Inorg Chem ; 62(8): 3601-3608, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36790893

RESUMO

Near-infrared (NIR) phosphor-converted light-emitting diodes with broadband emission have received considerable interest. However, there remains a challenge in the construction of ultra-broadband NIR phosphors, hindering their further application. In this work, a heterovalent substitution strategy is proposed to construct a novel ultra-broadband NIR-emitting LaTiTaO6:Cr3+ phosphor with a full width at half maximum of ∼300 nm. Crystal structure, time-resolved emission spectroscopy, and electron paramagnetic resonance analyses confirm that only one crystallographic site of Cr3+ with separated ions exists. Electron and phonon coupling (EPC) evaluated by the Huang-Rhys factor (S) reveals that the heterovalent substitution strategy contributes to strong EPC with S = 9.185, resulting in ultra-broadband emission. Interestingly, a remarkable blue shift of emission from 1050 to 922 nm with increasing temperature is observed. Moreover, the application of LaTiTaO6:Cr3+ phosphor is demonstrated in the qualitative analysis of ethanol/water mixtures. The work will enrich the toolbox for designing broadband NIR-emitting materials.

18.
Inorg Chem ; 62(33): 13370-13377, 2023 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-37560992

RESUMO

As far as we are concerned, the phenomenon of Ni2+ luminescence in tetrahedral coordination has not been reported. For the first time, a new NIR phosphor Ca2GeO4:Ni2+ is developed in this work. It is found that the NIR emission from this phosphor is a sharp peak attributed to the unusual Ni2+-occupied GeO4 site in the lattice, instead of the conventional broadband luminescence of Ni2+ in the octahedrally coordinated site. Crystal-field analysis has been applied, and the parameters Dq, B, and Δ are calculated to reveal the relationship between the emission profile and the crystal field strength. The optimal Ni2+ doping concentration is found to be 1%. Ca2GeO4:Ni2+ provides an efficient sharp-line (fwhm = 16 nm) emission centered at 1164 nm which originates from the 1T2 → 3T1 transition with an internal quantum efficiency of 23.1% and a decay lifetime of about 300 µs. This work could provide some new insights to explore novel NIR luminescent materials based on transition-metal elements.

19.
Int J Mol Sci ; 24(4)2023 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-36835087

RESUMO

MicroRNAs play key regulatory roles in plant development. The changed pattern of miRNA expression is involved in the production of viral symptoms. Here, we showed that a small RNA, Seq119, a putative novel microRNA, is associated with the low seed setting rate, a viral symptom of rice stripe virus (RSV)-infected rice. The expression of Seq 119 was downregulated in RSV-infected rice. The overexpression of Seq119 in transgenic rice plants did not cause any obvious phenotypic changes in plant development. When the expression of Seq119 was suppressed in rice plants either by expressing a mimic target or by CRISPR/Cas editing, seed setting rates were extremely low, similar to the effects of RSV infection. The putative targets of Seq119 were then predicted. The overexpression of the target of Seq119 in rice caused a low seed setting rate, similar to that in Seq119-suppressed or edited rice plants. Consistently, the expression of the target was upregulated in Seq119-suppressed and edited rice plants. These results suggest that downregulated Seq119 is associated with the low seed setting rate symptom of the RSV in rice.


Assuntos
MicroRNAs , Oryza , Tenuivirus , MicroRNAs/genética , Tenuivirus/genética , Oryza/genética , Doenças das Plantas/genética
20.
Clin Gastroenterol Hepatol ; 20(6): 1259-1268.e7, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34718170

RESUMO

BACKGROUND & AIMS: The natural course of gastric mild-moderate dysplasia in a country with high incidence of gastric cancer (GC) is relatively unknown. We aimed to determine the long-term cumulative incidence of and risk factors for advanced neoplasia in patients with gastric dysplasia. METHODS: This was a single-center observational study including all consecutive patients diagnosed with gastric mild-moderate dysplasia between 2000 and 2017. Follow-up data were collected until December 2019. We determined the cumulative incidence of advanced neoplasia and identified risk factors with Cox regression. RESULTS: A total of 3489 consecutive participants were followed for a median of 4.19 years from initial mild-moderate dysplasia diagnosis. The median surveillance interval between index endoscopy and next follow-up endoscopy was 1.08 years, and more than half of patients had at least 3 surveillance gastroscopies. During the study period, the majority of participants did not show disease progression, either with dysplasia not detected (51.4%) or with persistent dysplasia (46.1%). There were 88 (2.9%) patients (5.13 per 1000 patient-years) who progressed to advanced neoplasia within a median of 4.3 years. The annual incidence of advanced neoplasia and GC were 0.43% and 0.26%, respectively, within 5 years of mild-moderate dysplasia diagnosis. Increasing age, male sex, moderate dysplasia, dysplasia detected in fundus or cardia at index endoscopy, and persistent Helicobacter pylori infection during follow-up were independent risk factors for developing advanced neoplasia. CONCLUSIONS: Even in a country with high incidence of GC, the majority of patients with gastric mild-moderate dysplasia did not experience disease progression in the long term. Intensified surveillance during the first 5 years after mild-moderate dysplasia detection is suggested.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Lesões Pré-Cancerosas , Neoplasias Gástricas , Progressão da Doença , Gastroscopia , Humanos , Hiperplasia , Incidência , Masculino , Lesões Pré-Cancerosas/epidemiologia , Fatores de Risco , Neoplasias Gástricas/epidemiologia
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