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1.
Pestic Biochem Physiol ; 199: 105769, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38458678

RESUMO

The discovery of safe, effective, and selective chemical algicides is the stringent need for the algicides development, and it is also one of the effective routes to control cyanobacteria harmful algal blooms and to meet the higher requirements of environmental and ecological. In this work, a series of novel bromo-N-phenyl-5-o-hydroxyphenylpyrazole-3-carboxyamides were rationally designed as pseudilin analogs by bioisosteric replacement and molecular hybridization strategies, in which the pyrrole unit of pseudilin was replaced with pyrazole and further combined with the dominant structural fragments of algicide diuron. The synthesis was carried out by a facile four-step routeincluding cyclization, amidation, transanulation, and halogenation. The biological activity evaluation on AtIspD, EcIspD, Synechocystis sp. PCC6803 and Microcystis aeruginosa FACHB905 revealed that most compounds had good EcIspD and excellent cyanobacteria inhibitory activity. In particular, compound 6bb exhibited potent algicidal activity against PCC6803 and FACHB905 with EC50 = 1.28 µM and 0.37 µM, respectively, 1.4-fold and 4.0-fold enhancement compared to copper sulfate (EC50 = 1.79 and 1.49 µM, respectively), and it also showed the best inhibitory activity of EcIspD. The binding of 6bb to EcIspD was explored by molecular docking, and it was confirmed that 6bb could bind to the EcIspD active site. Compound 6bb was proven to be a potential structure for the further development of novel algicides that targets IspD in the MEP pathway.


Assuntos
Herbicidas , Microcystis , Synechocystis , Simulação de Acoplamento Molecular , Inibidores Enzimáticos/farmacologia , Synechocystis/química , Synechocystis/metabolismo , Herbicidas/farmacologia
2.
J Comput Chem ; 45(14): 1087-1097, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38243618

RESUMO

A series of pentagonal bipyramidal anionic germanium clusters doped with heavy rare earth elements, REGe 6 - (RE = Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu), have been identified at the PBE0/def2-TZVP level using density functional theory (DFT). Our findings reveal that the centrally doped pentagonal ring structure demonstrates enhanced stability and heightened aromaticity due to its uniform bonding characteristics and a larger charge transfer region. Through natural population analysis and spin density diagrams, we observed a monotonic decrease in the magnetic moment from Gd to Yb. This is attributed to the decreasing number of unpaired electrons in the 4f orbitals of the heavy rare earth atoms. Interestingly, the system doped with Er atoms showed lower stability and anti-aromaticity, likely due to the involvement of the 4f orbitals in bonding. Conversely, the systems doped with Gd and Tb atoms stood out for their high magnetism and stability, making them potential building blocks for rare earth-doped semiconductor materials.

3.
Comput Math Methods Med ; 2022: 1310841, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35126616

RESUMO

This study was to investigate the value of echocardiographic data in assessing changes in cardiac function before and after transcatheter closure in children and adult patients with patent ductus arteriosus (PDA). In this study, 150 patients with isolated PDA treated by cardiac catheterization and transcatheter closure were selected as the study sample. Real-time color Doppler echocardiography was used both after and after operation. The results showed that the left ventricle returned to normal in 75 patients one day after operation, with an average age of 10.95 ± 3.27 years; the left ventricle did not return to normal in 10 patients 360 days after operation, with an average age of 64.31 ± 7.05 years. Left ventricular end diastolic volume index (LVEDVI) and left ventricular end systolic volume index (LVESVI) of patients decreased significantly one day after operation and remained at 51.95 ± 9.55 mL/m2 and 20.36 ± 8.11 mL/m-2, respectively. In summary, echocardiographic data have a high reference value in assessing cardiac function characteristics in children and adult patients with PDA and are worthy of further promotion.


Assuntos
Permeabilidade do Canal Arterial/diagnóstico por imagem , Permeabilidade do Canal Arterial/cirurgia , Ecocardiografia/métodos , Adolescente , Adulto , Idoso , Fenômenos Fisiológicos Cardiovasculares , Criança , Biologia Computacional , Permeabilidade do Canal Arterial/fisiopatologia , Ecocardiografia/estatística & dados numéricos , Ecocardiografia Doppler em Cores/métodos , Ecocardiografia Doppler em Cores/estatística & dados numéricos , Feminino , Testes de Função Cardíaca , Sopros Cardíacos/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Dispositivos de Oclusão Vascular , Função Ventricular Esquerda , Adulto Jovem
4.
Technol Health Care ; 29(S1): 327-334, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33682769

RESUMO

BACKGROUND: The stratum corneum (SC) is the outermost layer of human skin and deemed as barrier against chemical exposure and water loss. Moisturizers have beneficial effects in treating dry skin, especially the SC. Confocal Raman spectroscopy (CRS) was used to evaluate the efficacy of moisturizers on skin hydration and penetration, with such agents posing inherent characteristics of being noninvasive, nondestructive, timesaving, and cost effective. Bionics vernix caseosa (BVC) cream mimics the composition of vernix caseosa (VC), which could protect the newborn skin. METHODS: This research applied CRS to evaluate the penetration depth and water content variation during the intervention with two moisturizers, BVC cream and Vaseline. Volunteers received the 2 h application of BVC cream and Vaseline on the forearms. The evaluations on 0 h, 2 h, 4 h and 6 h were performed clinical assessment. Experimental data was processed by least square method and analysis of variance (ANOVA). RESULTS: The penetration depth of Vaseline was deeper than that of Bionics vernix caseosa cream. Specifically, BVC cream penetrated 18 µm into human skin, while Vaseline penetrated at least 20 µm. Compared with Vaseline, only BVC cream increased skin hydration, with a moisturizing effect lasting for 4 h. At 6 h, the Vaseline moisturizing effect decreased significantly.


Assuntos
Verniz Caseoso , Biônica , Humanos , Recém-Nascido , Vaselina , Pele , Análise Espectral Raman
5.
Skin Res Technol ; 26(6): 898-904, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32585081

RESUMO

BACKGROUND: Surfactant is widely used in skin care products and cleansers, while it may cause physical discomfort. In this study, in vivo Raman spectroscopy was used to explore surfactant irritation mechanism on skin, which was not found in literature. METHODS: Sodium dodecyl sulfate (SDS) was chosen to represent surfactant. Research on the negative effect of SDS was undertaken by scanning the two states of the skin (without and with the contact of SDS), respectively, on six volunteers, by means of Raman technique and skin magnifier. RESULTS: The damage to the surface of normal skin by SDS was visible from the photographs taken by skin magnifier, and the apparent damage matched the damage that was happening underneath the skin elucidated by Raman spectra. Compared to the normal skin, the inter-cellular lipids (ICL) lateral packing order of the damaged skin was significantly reduced in 2-12 µm of skin depth (P < 0.05), deeper than 12 µm was not detected. The skin depth of 0-2 µm could not be determined due to strong interference of SDS. Significant change in the secondary and tertiary structures of keratin was not found.


Assuntos
Cosméticos/farmacologia , Pele/efeitos dos fármacos , Análise Espectral Raman , Tensoativos/farmacologia , Humanos , Absorção Cutânea , Dodecilsulfato de Sódio/farmacologia
6.
Anal Chem ; 92(6): 4656-4662, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32077685

RESUMO

Microplastics (MPs) pollution has drawn increasing concern due to its widespread occurrence and potential risks in the environment. The reliable methods and instruments for fast analysis of microplastics (MPs) less than 5 mm are urgently needed. In this study, a new method based on custom-made portable pyrolysis-mass spectrometry (Pyr-MS) is developed, which enables rapid identification and mass related quantification of MPs. MPs are decomposed in the compact pyrolyzer and then directly analyzed in the portable MS by the chemical fingerprints of polymers including characteristic ions and their special ratio. It avoids the complex extraction and separation procedures of the pyrolysis/thermogravimetric-gas chromatography-mass spectrometry (Pyr/TGA-GC-MS), realizes the rapid analysis of MPs in 5 min, and thus can practically apply to a large number of MPs samples. In comparison to Fourier transform infrared spectroscopy (FT-IR) and Raman, this method is not limited by the shape, size, and color of MPs. Four common plastics including polyethylene (PE), polypropylene (PP), polystyrene (PS), and poly(methyl methacrylate) (PMMA) were investigated to verify the feasibility of this method. The environmental MPs samples collected from a beach were successfully identified and quantified, demonstrating the simplicity and practicality of this approach. The influence of plastics aging on the chemical fingerprints and the potential of mixed plastics detection by Pyr-MS are also assessed. The portable Pyr-MS could provide a promising tool for in-field analysis of MPs such as ship-based marine MPs surveys.

7.
Chem Sci ; 11(9): 2342-2349, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-34084394

RESUMO

While the external quantum efficiency (EQE) of iridium(iii) (Ir(iii)) phosphor based near-infrared organic light-emitting diodes (NIR OLEDs) has been limited to 5.7% to date, there is no significant EQE improvement for these types of OLEDs due to the lack of efficient Ir(iii) emitters. Here, a convenient approach within three synthetic steps is developed to afford two novel and efficient deep-red to near-infrared (DR-NIR) emitting phosphors (CNIr and TCNIr), in which a cyano group is added into a commercial red emitter named Ir(piq)2(acac) to significantly stabilize the lowest unoccupied molecular orbitals of the newly designed Ir(iii) complexes. They emit strong DR-NIR phosphorescence emissions at a wavelength of around 700 nm, with relatively high absolute quantum efficiencies of around 45% for their doped films. DR-NIR OLEDs made using CNIr and TCNIr exhibit high-efficiencies, affording peak EQEs of 10.62% and 9.59% with emission peak wavelengths of 690 and 706 nm, respectively. All these devices represent the most efficient Ir(iii)-based DR-NIR OLEDs with a similar color gamut. The simplified synthesis procedure of the DR-NIR-emitting phosphors in conjunction with their excellent performance in OLEDs confirms our efficient strategy to achieve the DR-NIR-emitting Ir(iii) phosphors.

8.
Food Chem ; 310: 125824, 2020 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31732245

RESUMO

In this work, a home-made portable dielectric barrier discharge-atomic emission spectrometer (DBD-AES) was explored to the determination of heavy metal in foodstuffs. A rapid and simple method was developed for Cd determination in rice based on this instrument. Rice was pretreated with diluted acid dissolution without complex operations and apparatus. The detection time by DBD-AES is about 3 min and the total analysis time for rice sample is within 11 min. The effects of some key experiment parameters were investigated. The limit of detection was 11.9 µg kg-1 for Cd in rice, much lower than the maximum allowable level established by EC (200 µg kg-1). The practical performance of this method was demonstrated by analyzing real and CRM rice samples. With the portability of DBD-AES, the method is suitable for rapid and in-field analysis of Cd in rice. It will be a useful tool for the routine analysis of rice.


Assuntos
Cádmio/análise , Análise de Alimentos/instrumentação , Contaminação de Alimentos/análise , Oryza/química , Espectrofotometria Atômica/instrumentação , Análise de Alimentos/métodos , Limite de Detecção , Espectrofotometria Atômica/métodos , Fatores de Tempo
9.
BMC Womens Health ; 19(1): 73, 2019 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182098

RESUMO

BACKGROUND: Breast angiosarcoma is rare and previous studies only focus on its pathology. This study aimed to summarize its imaging features. METHODS: Overall 17 patients pathologically confirmed with breast angiosarcoma were recruited. Eight patients underwent preoperative mammography, and 13 received preoperative MRI scan. The mammography and MRI findings were classified according to the ACR-BI-RADS-mammography/MR lexicon. RESULTS: Mammography showed that 3 cases developed diffuse asymmetry occupying two or more quadrants of the affected breast and that 5 patients had lobulated or oval masses. The 13 patients' lesions presented as diffuse and slightly/significantly high homogeneous or heterogeneous signals on T1-weighted images, while the necrotic and cystic parts had relatively low signals. The hemorrhagic lesions in 7 cases had high signals on both T1- and T2-weighted images. A hemosiderin ring at the edge of an old hemorrhagic lesion had long and short signals on the T1- and T2-weighted images, respectively. Contrast-enhanced MRI revealed that the 13 patients' lesions had significant heterogeneous enhancement. Significant enhancement was observed in the early phase, and varying degrees of concentric enhancement was seen in the delayed phase. CONCLUSIONS: The mammography findings are nonspecific. MRI scan is helpful in determining the malignancy of the lesions. Breast angiosarcoma usually shows heterogeneous signals on both T1-weighted and T2-weighted images. Due to their incomplete lumens and lack of thrombocytes, patients with angiosarcoma have a higher incidence of bleeding (nearly 50% in this study) than those with other malignant tumors. The pattern of the enhancement curve helps to distinguish this disease from the typical types of breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Hemangiossarcoma/diagnóstico por imagem , Hemangiossarcoma/patologia , Imageamento por Ressonância Magnética/métodos , Mamografia/métodos , Adulto , Idoso , Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Medição de Risco
10.
Med Sci Monit ; 25: 2640-2648, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30969950

RESUMO

BACKGROUND Reports show that ultrasound-targeted microbubble destruction (UTMD) is a promising method of gene therapy, and metadherin (MTDH) is related to the development of breast cancer. Thus, we investigated the role of MTDH in breast cancer and compared the effect of suppressing MTDH by shRNA using liposome, UTMD, or the combination of these 2 methods. MATERIAL AND METHODS Graphing of survival curves of MTDH was analyzed by bioinformatics. UTMD was conducted using an ultrasonic therapeutic apparatus. Cell counting kit-8 (CCK-8) assay was used to measure cell viability. Migration and invasion rates were measured by wound healing test and Transwell invasion assay, respectively. The expression of MTDH, E-cadherin, metastasis-associated protein-1 (MTA-1), matrix metalloproteinase (MMP)-2, and MMP-9 were measured by Western blot and qPCR. RESULTS The prognosis of breast cancer can be decreased by the high expression of MTDH, and elevated expression of MTDH was discovered in MCF-7, MCF-10A, and T47D cell lines. UTMD combined with liposome is most efficient in transfecting shRNA, clearly suppressing the expression of MTDH and thereby decreasing cell viability, migration, invasion rate, and epithelial- mesenchymal transition (EMT) processes in the MCF-7 cell line. CONCLUSIONS UTMD combined with liposome could be used as a more efficient way to transfect shRNA into cells to suppress the expression of MTDH and thus lead to the downregulation of proliferation, migration, and EMT processes of the MCF-7 cell line, showing the potential for use in gene therapy.


Assuntos
Moléculas de Adesão Celular/metabolismo , Movimento Celular , Transição Epitelial-Mesenquimal , Microbolhas , RNA Interferente Pequeno/metabolismo , Ultrassom , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Regulação para Baixo , Feminino , Humanos , Lipossomos , Proteínas de Membrana , Invasividade Neoplásica , Prognóstico , Proteínas de Ligação a RNA , Cicatrização
11.
Anal Chem ; 89(4): 2205-2210, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28192915

RESUMO

This paper describes the first demonstration of a portable dielectric barrier discharge-atomic emission spectrometer (DBD-AES). The instrument primarily consists of a miniature electro-thermal vaporizer (ETV), DBD, and optical signal acquisition units. It weighs only 4.5 kg and is powered by a 24 V DC battery with a maximum power consumption of 37 W. The accompanying software can be operated on a laptop computer. A specially designed quartz tube integrates the ETV unit with the DBD chamber. The effects of experimental parameters were investigated. The limit of detection (LOD) for mercury was 0.4 µg L-1 (1.2 pg) with a sampling volume of 3 µL. The instrument is applicable for multielement analysis, and the LODs ranged from 0.16 to 11.65 µg L-1 for Zn, Pb, Ag, Cd, Au, Cu, Mn, Fe, Cr, and As. The instrument was also validated by in-field analysis of seawater samples. The experimental results demonstrated the sensitivity, reliability, and practicality of the instrument.

12.
Se Pu ; 31(2): 162-9, 2013 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-23697183

RESUMO

A new method was established to determine three stilbene-type disulfonate and one distyrylbiphenyl-type fluorescent whitening agents (FWA351, FWA85, FWA28 and FWA71) in laundry detergents by solid phase extraction (SPE) and ultra-high performance liquid chromatography with a diode array detector (UPLC-DAD). The fluorescent whitening agents were extracted from laundry detergents with 2% formic acid aqueous solution and methanol, and purified by WAX SPE column, and analyzed by UPLC-DAD on a Phenomenex Synergi Max-RP column (150 mm x 2.0 mm), employing acetonitrile-10 mmol/L ammonium acetate as the mobile phase in a gradient elution mode. The fluorescent whitening agents were qualitatively determined by retention time, and confirmed by the ultraviolet spectrum. The results indicated that the target analytes were in the range of 0.05-180 mg/L with the correlation coefficients (r) greater than 0. 999 3, and the method limits of quantification (MLOQ) of target analytes were ranged from 1.5 mg/kg to 15 mg/kg (S/N = 10). The feasibility of this method was demonstrated by the determination of FWAs in samples with spiked recoveries. The recoveries were in the range between 84.9% and 105%, and the precision (relative standard deviation, RSD) ranged from 3.2% to 6.1% (n = 6). Among the 15 samples analyzed, the rate of positive samples was 53.3%, over 1 000 mg/kg of FWA351 and FWA71 were detected. The method is simple, precise and has high recoveries for the determination of fluorescent whitening agents in laundry detergent samples.

13.
Chemosphere ; 60(7): 944-50, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15878610

RESUMO

A practical and efficient disposal method for hydrodechlorination of polychlorinated biphenyls (PCBs) in transformer oil is reported. Transformer oil containing PCBs was treated by nanometric sodium hydride (nano-NaH) and transition metal catalysts. High destruction and removal efficiency (89.8%) can be attained by nano-NaH alone under mild conditions. The process exhibits apparent characteristics of a first order reaction. The reductive ability of nano-NaH was enhanced by the addition of transition metal catalysts. In the presence of TiCl4, 99.9% PCBs was hydrodechlorinated. The complex reducing reagents, Ni(OAc)2+i-PrONa, show extra hydrodechlorinating activity for di-chlorinated biphenyls.


Assuntos
Cloro/química , Óleos/química , Bifenilos Policlorados/química , Compostos de Sódio/química , Gerenciamento de Resíduos/métodos , Catálise , Cobalto , Eletricidade , Óleos Industriais , Resíduos Industriais , Microquímica , Níquel , Oxirredução , Titânio
14.
Chem Commun (Camb) ; (10): 1172-3, 2003 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-12778720

RESUMO

Copper and manganese were found to be two concordant partners in the synthesis of p-hydroxybenzaldehyde from p-cresol; under mild conditions, this research realised 95.6% selectivity for p-hydroxybenzaldehyde at 98.5% conversion of p-cresol.

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