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1.
Chin J Traumatol ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637176

RESUMO

PURPOSE: Traumatic brain injury (TBI), currently a major global public health problem, imposes a significant economic burden on society and families. We aimed to quantify and predict the incidence and severity of TBI by analyzing its incidence, prevalence, and years lived with disability (YLDs). The epidemiological changes in TBI from 1990 to 2019 were described and updated to provide a reference for developing prevention, treatment, and incidence-reducing measures for TBI. METHODS: A secondary analysis was performed on the incidence, prevalence, and YLDs of TBI by sex, age group, and region (n = 21,204 countries and territories) between 1990 and 2019 using the Global Burden of Diseases, Injuries, and Risk Factors Study 2019. Proportions in the age-standardized incidence rate due to underlying causes of TBI and proportions of minor and moderate or severe TBI were also reported. RESULTS: In 2019, there were 27.16 million (95% uncertainty intervals (UI): 23.36 - 31.42) new cases of TBI worldwide, with age-standardized incidence and prevalence rates of 346 per 100,000 population (95% UI: 298-401) and 599 per 100,000 population (95% UI: 573-627), respectively. From 1990 to 2019, there were no significant trends in global age-standardized incidence (estimated annual percentage changes: -0.11%, 95% UI: -0.18% - -0.04%) or prevalence (estimated annual percentage changes: 0.01%, 95% UI: -0.04% - 0.06%). TBI caused 7.08 million (95% UI: 5.00 - 9.59) YLDs in 2019, with age-standardized rates of 86.5 per 100,000 population (95% UI: 61.1 - 117.2). In 2019, the countries with higher incidence rates were mainly distributed in Central Europe, Eastern Europe, and Australia. The 2019 global age-standardized incidence rate was higher in males than in females. The 2019 global incidence of moderate and severe TBI was 182.7 per 100,000 population, accounting for 52.8% of all TBI, with falls and road traffic injuries being the main causes in most regions. CONCLUSIONS: The incidence of moderate and severe TBI was slightly higher in 2019, and TBI still accounts for a significant portion of the global injury burden. The likelihood of moderate to severe TBI and the trend of major injury under each injury cause from 1990 to 2019 and the characteristics of injury mechanisms in each age group are presented, providing a basis for further research on injury causes in each age group and the future establishment of corresponding policies and protective measures.

2.
Toxics ; 12(2)2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38393240

RESUMO

1,4-dioxane is a potential carcinogen in water and is difficult to deal with due to its robust cycloether bond and complete miscibility with water. To remove 1,4-dioxane in an economically viable and environmentally friendly way, a series of carbon aerogels were synthesized as adsorbents for 1,4-dioxane. The experiment results showed that adsorption performances were closely related to the preparation conditions of carbon aerogels, such as the molar ratio, heating rate, pyrolysis temperature and residence time, which were carefully controlled. Scanning electron microscope analysis revealed the presence of a three-dimensional porous network structure in carbon aerogels. Brunauer-Emmett-Teller analysis results demonstrated an increase in specific surface area (673.89 m2/g) and total pore volume after carbonization, with an increase in mesoporous porosity and a decrease in microporosity. When considering each variable individually, the highest specific surface area of prepared carbon aerogels was achieved at a pyrolysis temperature of 800 °C, a holding time of 1 h, and a heating rate of 2 °C/min. Under optimal experimental conditions, the adsorption removal of 1,4-dioxane by carbon aerogels exceeded 95%, following quasi-second-order kinetics and Langmuir isothermal adsorption isotherms, indicating that monolayer adsorption on the surface of carbon aerogels occurred. The maximum adsorption capacity obtained was 67.28 mg/g at a temperature of 318 K, which was attributed to the presence of a large proportion of mesopores and abundant micropores simultaneously in carbon aerogels. Furthermore, with the interference of chlorinated solvents such as trichloroethylene (TCE), the removal efficiency of 1,4-dioxane had no obvious inhibition effect. Regeneration experiments showed that after five continuous cycles, the carbon aerogels still kept a comparable adsorption capacity, which illustrates its potential application in 1,4-dioxane-polluted water purification.

3.
Sci Adv ; 9(51): eadk1704, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38117883

RESUMO

Here, an Ir/Zn-cocatalyzed atroposelective [2+2+2] cycloaddition of 1,6-diynes and ynamines was developed, forging various functionalized C─N axially chiral indoles and pyrroles in generally good to excellent yields (up to 99%), excellent chemoselectivities, and high enantioselectivities (up to 98% enantiomeric excess) with wide substrate scope. This cocatalyzed strategy not only provided an alternative promising and reliable way for asymmetric alkyne [2+2+2] cyclotrimerization in an easy handle but also settled the issues of previous [Rh(COD)2]BF4-catalyzed system on the construction of C─N axial chirality such as complex operations, limited substrate scope, and low efficiency. In addition, control experiments and theoretical calculations disclosed that Zn(OTf)2 markedly reduced the barrier of migration insertion to significantly increase reaction efficiency, which was distinctly different from previous work on the Lewis acid for improving reaction yield through accelerating oxidative addition and reductive elimination.

4.
J Am Chem Soc ; 144(1): 339-348, 2022 01 12.
Artigo em Inglês | MEDLINE | ID: mdl-34935377

RESUMO

A copper-catalyzed remote benzylic C-H functionalization strategy enabling 1,2-difunctionalization of alkenes with 2-methylbenzeneamides and nucleophiles, including alcohols, indoles, pyrroles, and the intrinsic amino groups, is reported, which is characterized by its redox-neutral conditions, exquisite site-selectivity, broad substrate scope, and wide utilizations of late-stage modifying bioactive molecules. This reaction proceeds through nitrogen-centered radical generation, hydrogen atom transfer, benzylic radical addition across the alkenes, single-electron oxidation, and carbocation electrophilic course cascades. While using external nucleophiles manipulates three-component alkene alkylalkoxylation and alkyl-heteroarylation with 2-methylbenzeneamides to access dialkyl ethers, 3-alkylindoles, and 3-alkylpyrroles, omitting the external nucleophiles results in two-component alkylamidation ([5+2] annulation) of alkenes with 2-methylbenzeneamides to benzo-[f][1,2]thiazepine 1,1-dioxides.

5.
Chem Commun (Camb) ; 57(30): 3684-3687, 2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33725052

RESUMO

We have developed a new radical-mediated alkoxypolyhaloalkylation of styrenes with polychloroalkanes and alcohols for the facile synthesis of complex polyhaloalkanes. 4-Methoxybenzenediazonium tetrafluoroborate is a good radical initiator for this transformation. This protocol is well applied to the late-stage functionalization of complex molecules, including vitamin E, estrone and cholesterol derivatives.

6.
Org Lett ; 23(3): 1000-1004, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33476163

RESUMO

We have disclosed a new radical-mediated decarboxylative C(sp3)-N cross-coupling of diacyl peroxides with nitrogen nucleophiles. The primary and secondary alkyl radicals derived from corresponding diacyl peroxides were generated by copper catalysis or by merging copper catalysis and photoredox catalysis, respectively. Various N-alkyl nitrogen nucleophiles, including indazoles, triazoles, indoles, purine, carbazole, anilines, and sulfonamide, were provided with a broad substrate scope and good functional group tolerance.


Assuntos
Nitrogênio/química , Peróxidos/química , Compostos de Anilina/química , Carbazóis/química , Catálise , Cobre/química , Estrutura Molecular
7.
Chem Commun (Camb) ; 56(90): 14055-14058, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33103675

RESUMO

We have developed a new oxidative decarboxylation of cinnamic acids with 4-alkyl-1,4-dihydropyridines to construct C(sp3)-C(sp2) bonds in the presence of copper catalyst and dicumyl peroxide (DCP). A variety of internal alkenes have been obtained with mild conditions, broad substrate scope and excellent functional group tolerance. This method has significant potential for application by using inexpensive and stable cinnamic acids instead of alkenyl halides and nitro-olefins.

8.
Org Lett ; 22(18): 7250-7254, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-32852217

RESUMO

A general, ideal atom utilization electrochemical technology to enable alkene alkoxyhalogenation and organohalide dehalogenation in one pot is presented. This technology is highlighted by convergent strategy integrating several reactions, such as alkene alkoxyhalogenation, organohalide dehalogenation, and dehalogenation deuteration. Experimental data suggest that alkenes have the lowest oxidation potential, which lead to anodic conversion of the C═C bond to the radical cation intermediates, and cathodic transformations of organohalides, including alkyl and aryl halides, as the nucleophilic halogen sources.

9.
Org Biomol Chem ; 18(25): 4843-4847, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32608447

RESUMO

A simple and practical method for the synthesis of phosphoryl-substituted indolo[2,1-a]isoquinolin-6(5H)-ones and benzimidazo[2,1-a]isoquinolin-6(5H)-ones through manganese(iii)-promoted tandem phosphinoylation/cyclization of 2-arylindoles or 2-arylbenzimidazoles with disubstituted phosphine oxides was developed. In this transformation, new C-P bond and C-C bond were constructed simultaneously under silver-free conditions, exhibiting a broad substrate scope. It was noted that not only diarylphosphine oxides but also dialkyl and arylalkyl-phosphine oxides were compatible with the conditions.

10.
Chem Commun (Camb) ; 56(55): 7585-7588, 2020 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-32510076

RESUMO

A new external oxidant-free electrochemical dehydrogenative cross-coupling of xanthenes and ketones for the preparation of functionalized 9-alkyl-9H-xanthenes was developed. This method enables the formation of a new C(sp3)-C(sp3) bond through release of H2 as the major byproduct at room temperature, and features mild conditions, high atom economy, excellent functional-group tolerance, scalability and facile applications in pharmaceutical chemistry.

11.
Cancer Manag Res ; 12: 3865-3875, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32547223

RESUMO

OBJECTIVE: This study set out to explore the regulatory mechanism of miR-130a-5p in cisplatin (DDP)-resistant gastric cancer (GC) cells. MATERIALS AND METHODS: Forty cases of GC and paracancerous tissues were collected, and the miR-130a-5p and CCL22 levels were detected by qRT-PCR. DDP-resistant cell lines of GC cells were established. Cell viability, invasion, and apoptosis were measured by CCK-8, Transwell, and flow cytometry, respectively. The relationship between miR-130a-5p and CCL22 was verified by dual-luciferase reporter enzyme, and the protein levels of caspase-3, bax, bcl-2, and CCL22 were determined by Western blot. RESULTS: miR-130a-5p was low expressed in GC tissues and cells, while CCL22 showed marked negative correlation, and the area under the curve (AUC) for diagnosing GC was not less than 0.850. Up-regulating miR-130a-5p or knocking down CCL22 expression can inhibit the proliferation and invasion of GC cells and promote their apoptosis, reverse the resistance of NCI-N87/DDP to DDP, and also enhance the chemosensitivity of GC cells. Dual-luciferase reporter enzyme identified that there was a targeted relationship between miR-130a-5p and CCL22. At the same time, miR-130a-5p and CCL22 were up-regulated or down-regulated, and the malignant proliferation, invasion, apoptosis, and DDP chemotherapy resistance of the cells had no difference compared with miR-NC with transfection-unrelated sequences. CONCLUSION: Up-regulating miR-130a-5p can enhance the sensitivity of DDP-resistant GC cells to chemotherapy and regulate their biological function by targeted inhibition of CCL22.

12.
Org Biomol Chem ; 18(11): 2170-2174, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32140694

RESUMO

A copper-catalyzed C-H [3 + 2] annulation of N-substituted anilines with α-carbonyl alkyl bromides for the synthesis of 3,3'-disubstituted oxindoles is developed. Tandem C-H cycloamidation reactions of various α-carbonyl alkyl bromide derivatives including tertiary-α-bromoalkyl ketone esters, malonic esters and cycloalkanes, with N-aryl or alkyl substituted anilines, can be performed using this system, affording a vast array of valuable 3,3'-disubstituted oxindoles in moderate to good yields.

13.
Chem Commun (Camb) ; 56(8): 1279-1282, 2020 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-31904057

RESUMO

We here describe a new, selective indium-promoted silver-mediated intermolecular oxidative 1,4-alkylarylation of 1,3-dienes with α-carbonyl alkyl bromides and N-heterocycles for producing functionalized N-heterocycles, which is characterized by its exquisitely controllable regio-/stereo-selectivity and excellent tolerance of functional groups. Mechanistically, the formation of the carbonyl-coordinated η3-allyl-In complex radical intermediate is the key factor for successfully achieving regio- and stereo-selectivity toward 1,4-difunctionalization and (E)-isomers.

14.
Chem Commun (Camb) ; 55(97): 14637-14640, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31746852

RESUMO

The In(OTf)3-promoted three-component photoredox alkylarylation of styrenes with alkyl NHP esters and arenes to access alkylated arene derivatives through C-C bond cleavage and C-H functionalization is reported. By utilizing visible-light photoredox catalysis, alkyl N-hydroxyphthalimide esters serving as alkyl carbon-centered radicals and a wide range of arenes (e.g., indoles, pyrrole, and electron-rich arenes) as nucleophiles were used to enable the introduction of various alkyl groups and aryl groups across the C[double bond, length as m-dash]C bonds with excellent selectivity and functional group tolerance.

15.
Chem Commun (Camb) ; 55(85): 12805-12808, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31595274

RESUMO

A new silver-mediated 1,2-alkylesterification of alkenes with nitriles and acids promoted by a catalytic amount of nickel catalyst for producing acyloxylated nitriles has been developed via a C(sp3)-H functionalization process. By employing the NiI2 and Ag2CO3 catalytic systems, the method features broad substrate scope with respect to carboxylic acids, including linear alkyl acids, cyclic acids, aryl acids and amino acids.

16.
Environ Sci Pollut Res Int ; 26(33): 34562-34574, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31650478

RESUMO

Novel adsorbent, diethylenetriamine-grafted Spirodela polyrhiza (DSP), was synthesized via modifying natural S. polyrhiza (SP) with diethylenetriamine by cross-linking with epichlorohydrin and applied to adsorb Ni2+ and Pb2+ from water. The effecting parameters on adsorption of Ni2+ and Pb2+ such as adsorbent dosage, pH, contact time, temperature, and initial concentration were studied through equilibrium experiments. The adsorption of Ni2+ and Pb2+ followed the pseudo-second-order model and the Langmuir isotherm adsorption model. The study discusses thermodynamic parameters, including changes in Gibbs free energy, entropy, and enthalpy, for the adsorption of Ni2+ and Pb2+ on DSP, and revealed that the adsorption process was spontaneous and exothermic under natural conditions. The maximum Ni2+ and Pb2+ adsorption capacities of DSP were 33.02 and 36.50 mg/g, respectively. The newly prepared materials were characterized through scanning electron microscopy (SEM), mapping analysis, and zeta potential analysis. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses indicated that functional groups (-OH and N-H) were involved in Ni2+ and Pb2+ adsorption. Notably, DSP can be easily regenerated and reused for multiple cycles. Therefore, DSP is a promising adsorbent for effective Ni2+ and Pb2+ removal.


Assuntos
Alismatales/química , Chumbo/química , Níquel/química , Poliaminas/química , Poluentes Químicos da Água/química , Adsorção , Epicloroidrina/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termodinâmica , Água , Poluentes Químicos da Água/análise , Purificação da Água/métodos
17.
Chem Commun (Camb) ; 55(74): 11111-11114, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31461103

RESUMO

A new, general silver-catalyzed oxidative 1,2-alkyletherification of unactivated olefinic ketones with primary, secondary and tertiary α-bromoalkyl carbonyls promoted by tert-butyl hydroperoxide (TBHP) and Et3N has been developed. Through the cooperative action of Ag2O, TBHP and Et3N, the reaction enables the construction of highly valuable quaternary-carbon-possessing 2,3-dihydrofuran frameworks using a concomitant intramolecular annulation strategy.

18.
Org Lett ; 21(16): 6285-6288, 2019 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-31369279

RESUMO

A new, general copper-catalyzed oxidative tandem [4+2] cycloaddition of α-(N-arylamino) carbonyl compounds with aryl alkenes to produce highly substituted quinolines has been developed, which allows the formation of three new C-C bonds through a sequence of multiple C-H functionalizations, annulation, and [1,2]-aryl shifts.

19.
Chem Commun (Camb) ; 55(61): 8995-8998, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31290859

RESUMO

A new, practical directed anodic C-H sulfonylation of N,N-disubstituted anilines with sodium sulfinates for producing o- or p-amino arylsulfones and diarylsulfones is described. Employing the anodic strategy, the reaction proceeds efficiently under mild (room temperature) and transition-metal- and chemical oxidant-free conditions, and enables the formation of C-S bonds via directed activation of ortho- or para-C-H bond to the amino group with broad substrate scope and excellent site selectivity.

20.
Environ Sci Pollut Res Int ; 26(21): 21189-21200, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31119533

RESUMO

By a simple and convenient method of using epichlorohydrin as linkages, a novel Alternanthera philoxeroides (AP) derivative modified with diethylenetriamine (DAP) was synthesized, which can remove copper(II) ions (Cu(II)) in the water environment efficiently. The adsorption capacity of DAP for Cu(II) under various factors was measured using ultraviolet spectrophotometer. The adsorption capacity and removal ratio were 19.33 mg/g and 95.57% at pH 5.5 and 298 K. The kinetic and equilibrium study shows that pseudo-second-order kinetic (R2 = 0.9964) and Langmuir isotherm models (R2 > 0.982) could properly describe DAP adsorption behaviors, and thermodynamic parameters indicate a spontaneous endothermic process (ΔG = - 3.6636 kJ/mol). The combined results of SEM, XRD, FTIR, and XPS analyses reveal that the dominant contribution for enhancement in Cu(II) adsorption is made by the formation of an amino group. And the adsorption mechanism is mainly the complexation reaction. The adsorption efficiency of DAP remained above 72.06% after 6 cycles of adsorption-desorption, which indicated that DAP has good regenerability and stability. All the results suggest that DAP could serve as promising adsorbents for Cu(II) pollution minimization.


Assuntos
Amaranthaceae/metabolismo , Biodegradação Ambiental , Cobre/metabolismo , Poluentes Químicos da Água/metabolismo , Adsorção , Cobre/análise , Epicloroidrina/química , Íons , Cinética , Poliaminas , Termodinâmica , Água/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos
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