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1.
J Tradit Chin Med ; 44(3): 609-619, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38767646

RESUMO

OBJECTIVE: To assess the quality of Clinical practice guidelines (CPGs) in the context of diabetic kidney disease (DKD) and determine whether any factors affect the quality. METHODS: We searched eight databases along with five international and national organizations to develop or archive guidelines from their inception to July 2023, with an additional search of medlive.cn. And the authoritative organizations related to nephrology. CPGs and consensus statements created using direct differential diagnosis or therapy for DKD were included without language restrictions. Their quality was evaluated by four reviewers using the Appraisal of Guidelines for Research and Evaluation Ⅱ (AGREE Ⅱ) instrument. Along with the item and domain scores, the guideline was also allocated an overall quality score, which ranged from 1 (lowest possible quality) to 7 (highest possible quality). Moreover, an overall recommendation for use was also assigned ("recommended", "recommended with modifications" or "not recommended"). RESULTS: A total of 16 CPGs were included, of which 14 were from Asia and the remaining two from Europe. These two CPGs were updated in the third version. Six CPGs were recommended for use because their primary domains scored in the medium or high category. Furthermore, five CPGs were recommended with modifications as the stakeholder involvement, applicability, and editorial independence domains were evaluated as low categories. In all domains, the lowest average score was for rigour of development (33%), followed by application (36%), and stakeholder involvement (51%). The highest average score was for scope and purpose (79%), followed by clarity of presentation (75%). None of the CPGs considered the patient's viewpoint, and six of 16 CPGs did not use any grading system to translate the evidence into recommendations. Additionally, only three of 16 CPGs shared search strategy, and eight of 16 CPGs did not declare a funding source. CONCLUSIONS: According to the AGREE II evaluation, more than one in four CPGs for DKD had poor methodological quality. Enhanced efforts are needed to advance the rigour of development, application, and editorial independence of DKD guideline panels for most guidelines. Stakeholders, CPG developers, and CPG users should consider methodological quality while choosing CPGs, and interpret and implement their issued suggestions.


Assuntos
Nefropatias Diabéticas , Guias de Prática Clínica como Assunto , Humanos , Nefropatias Diabéticas/terapia , Nefropatias Diabéticas/diagnóstico
2.
Sci Rep ; 14(1): 11464, 2024 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769093

RESUMO

Long-term exposure to ambient air pollution raises the risk of deaths and morbidity worldwide. From 1990 to 2019, we observed the epidemiological trends and age-period-cohort effects on the cardiovascular diseases (CVD) burden attributable to ambient air pollution across Brazil, Russia, India, China, and South Africa (BRICS). The number of CVD deaths related to ambient particulate matter (PM) pollution increased nearly fivefold in China [5.0% (95% CI 4.7, 5.2)] and India [5.7% (95% CI 5.1, 6.3)] during the study period. The age-standardized CVD deaths and disability-adjusted life years (DALYs) due to ambient PM pollution significantly increased in India and China but decreased in Brazil and Russia. Due to air pollution, the relative risk (RR) of premature CVD mortality (< 70 years) was higher in Russia [RR 12.6 (95% CI 8.7, 17.30)] and India [RR 9.2 (95% CI 7.6, 11.20)]. A higher period risk (2015-2019) for CVD deaths was found in India [RR 1.4 (95% CI 1.4, 1.4)] followed by South Africa [RR 1.3 (95% CI 1.3, 1.3)]. Across the BRICS countries, the RR of CVD mortality markedly decreased from the old birth cohort to young birth cohorts. In conclusion, China and India showed an increasing trend of CVD mortality and morbidity due to ambient PM pollution and higher risk of premature CVD deaths were observed in Russia and India.


Assuntos
Poluição do Ar , Doenças Cardiovasculares , Material Particulado , Humanos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/etiologia , Poluição do Ar/efeitos adversos , África do Sul/epidemiologia , China/epidemiologia , Federação Russa/epidemiologia , Material Particulado/efeitos adversos , Material Particulado/análise , Feminino , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Idoso , Brasil/epidemiologia , Adulto , Exposição Ambiental/efeitos adversos , Anos de Vida Ajustados por Deficiência , Poluentes Atmosféricos/efeitos adversos , Estudos de Coortes
3.
Org Lett ; 26(18): 3727-3732, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38678575

RESUMO

Photoexcitation electron donor-acceptor (EDA) complexes provide an effective approach to produce radicals under mild conditions, while the catalytic version of EDA complex photoactivation remains scarce. Herein, we report a visible-light-induced organophotocatalytic pathway for the cyanoalkylation of azauracils using inexpensive and readily available 1,4-diazabicyclo[2.2.2]octane (DABCO) as a catalytic electron donor. This synthetic method exhibits exceptional compatibility with various functional groups and presents 34 examples in high yields. The efficient cyanoalkylation offers an environmentally friendly and sustainable route toward enhancing the structural and functional diversity of azauracils.

4.
Chem Commun (Camb) ; 60(31): 4230-4233, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38526583

RESUMO

Lead-free perovskite microcrystals (MCs) have been regarded as promising potential photocatalysts, owing to their high molar extinction coefficient, low economic cost, adjustable light absorption range, and ample surface-active sites. Herein, C-3 thio/selenocyanation of indoles is demonstrated in high selectivity and yield by using lead-free double perovskite Cs2AgBiBr6 MCs under visible light irradiation. Moreover, the photocatalyst can be recycled at least 5 times without a significant decrease in catalytic activity.

5.
Chem Commun (Camb) ; 60(21): 2958-2961, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38375889

RESUMO

Visible-light-induced EDA complex-promoted ring-opening of cycloketone oxime esters to synthesise various cyanoalkylated products with N-methacryloyl benzamides was developed. Various radical receptors were compatible with the current reaction system to furnish diverse heterocyclic compounds. Mechanistic analysis shows that the formation of an EDA complex was crucial to the photocatalytic strategy. Importantly, 4-cyanoalkyl isoquinoline-1,3-diones were obtained in high yields by using a catalytic amount of 1,4-diazabicyclo[2.2.2]octane (DABCO) through prolonging the reaction time, which provided a practical approach to give a variety of isoquinoline-1,3-dione derivatives.

6.
Chem Commun (Camb) ; 60(18): 2516-2519, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38324066

RESUMO

Allyl sulfones are important sulfur-containing compounds that have widespread applications in organic synthesis, medicinal chemistry and materials science. Herein, nickel-catalysed dehydrosulfonylation of unactivated allyl alcohols with aryl sulfonyl hydrazides without additional active agents under mild conditions was developed. A variety of functional allyl sulfones could be efficiently synthesized in the presence of air-stable Ni(acac)2 as the catalyst and 1,1'-bis(diphenylphosphino)ferrocene (DPPF) as the ligand.

7.
Org Biomol Chem ; 22(5): 965-969, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38205855

RESUMO

A visible-light-induced decarboxylative cascade reaction of acryloylbenzamides with alkyl N-hydroxyphthalimide (NHP) esters for the synthesis of various 4-alkyl isoquinolinediones mediated by triphenylphosphine (PPh3) and sodium iodide (NaI) was developed. This operationally simple protocol proceeded via the photoactivation of electron donor-acceptor (EDA) complexes between N-hydroxyphthalimide esters and NaI/PPh3, resulting in multiple carbon-carbon bond formations without the use of precious metal complexes or synthetically elaborate organic dyes, which provided an alternative practical approach to synthesize diverse isoquinoline-1,3(2H,4H)-dione derivatives.

8.
Front Endocrinol (Lausanne) ; 14: 1267338, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38098860

RESUMO

Background: Gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy (HDP) are the predominant pregnancy complications among singleton and twin pregnancies worldwide. Our primary objective was to explore the adverse effect of GDM and HDP on maternal-perinatal outcomes compared with non-GDM and non-HDP in singleton and twin pregnancies. The secondary objective was to find the risk of adverse maternal-perinatal outcomes in twin pregnancies compared with singleton pregnancies complicated with GDM and HDP in Hubei, China. Methods: A tertiary hospital-based retrospective study was conducted at Wuhan University Renmin Hospital, Hubei Province, China, from 2011 to 2019. A chi-square test was used to determine the difference in adverse maternal-perinatal outcomes between singleton and twin pregnancies. A multiple binary logistic regression model and a joinpoint regression model were used to determine the association of GDM and HDP with adverse maternal-perinatal outcomes and GDM and HDP temporal trend among singleton and twin pregnancies. Results: The trend of HDP [average annual percentage change (AAPC) 15.1% (95% confidence interval (95%CI): 5.3, 25.7)] among singleton pregnancies and GDM [AAPC 50.4% (95%CI: 19.9, 88.7)] among twin pregnancies significantly increased from 2011 to 2019. After adjusting for confounding factors, GDM is associated with an increased risk of C-section (adjusted odds ratio (aOR), 1.5; 95%CI: 1.3, 1.6) and macrosomia (aOR, 1.3; 95%CI: 1.1, 1.6) in singleton and preterm birth (PTB) (aOR, 2.1; 95%CI: 1.2, 3.3) in twin pregnancies compared with non-GDM. HDP was associated with a higher risk of C-section, PTB, perinatal mortality, and low birth weight (LBW) in both singleton and twin pregnancies compared with the non-HDP. Compared with singleton pregnancies complicated with GDM and HDP, twin pregnancies showed higher odds of C-section [(aOR, 1.7; 95%CI: 1.1, 2.7), (aOR, 4.6; 95%CI: 2.5, 8.7), respectively], PTB [(aOR, 22.9; 95%CI: 14.1, 37.3), (aOR, 8.1; 95%CI: 5.3, 12.3), respectively], LBW [(aOR, 12.1; 95%CI: 8.2, 18.1), (aOR, 5.1; 95%CI: 3.6, 7.4), respectively], and low Apgar score [(aOR, 8.2; 95%CI: 4.4, 15.1), (aOR, 3.8; 95%CI: 2.4, 5.8), respectively] complicated with GDM and HDP. Conclusion: In conclusion, GDM showed an increased risk of a few adverse maternal-perinatal outcomes and HDP is associated with a higher risk of several adverse maternal-perinatal outcomes in singleton and twin pregnancies compared to non-GDM and non-HDP. Moreover, twin pregnancies complicated with GDM and HDP showed higher odds of adverse maternal-neonatal outcomes compared with singleton pregnancies complicated with GDM and HDP.


Assuntos
Diabetes Gestacional , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Hipertensão Induzida pela Gravidez , Doenças do Recém-Nascido , Pré-Eclâmpsia , Nascimento Prematuro , Gravidez , Feminino , Humanos , Recém-Nascido , Diabetes Gestacional/epidemiologia , Gravidez de Gêmeos , Estudos Retrospectivos , Resultado da Gravidez/epidemiologia , Hipertensão Induzida pela Gravidez/epidemiologia , Hipertensão Induzida pela Gravidez/etiologia , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia
9.
Chem Commun (Camb) ; 60(1): 106-109, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38032358

RESUMO

Organophotocatalytic cascade cross-dehydrogenative-coupling/cyclization reaction of o-hydroxyarylenaminones with α-amino acid derivatives for the construction of α-chromone substituted α-amino acid derivatives was developed. Various N-arylglycine esters, amides and dipeptides underwent the cascade cyclization reaction well with o-hydroxyarylenaminones to afford the corresponding 3-aminoalkyl chromones in good to excellent yields. This approach consists of visible-light-promoted oxidation of α-amino acid derivatives, the Mannich reaction, and intramolecular nucleophilic cyclization under acidic conditions, and features a wide reaction scope, a simple operation and mild reaction conditions, which may have the potential to be used for the synthesis of bioactive molecules.

10.
Nutrients ; 15(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37686788

RESUMO

BRICS-Plus countries (Brazil, Russia, India, China, South Africa, and 30 other countries) is a group of 35 countries with emerging economies making up more than half of the world's population. We explored epidemiological trends of cardiovascular disease (CVD) mortality attributable to modifiable risk factors and its association with period and birth cohort effects and sociodemographic index (SDI) across BRICS-Plus countries by using joinpoint regression and age-period-cohort modeling from 1990 to 2019. Between 1990 and 2019, the all-ages CVD deaths increased by 85.2% (6.1 million to 11.3 million) across BRICS-Plus countries. The CVD age-standardized mortality rate attributable to dietary risks and smoking significantly decreased across BRICS-Plus countries, with some exceptions. However, four-fifths of BRICS-Plus countries observed a remarkable increasing trend of high body mass-index (BMI)-related CVD deaths, in particular, among younger adults (25-49 years). Early birth cohorts and individuals aged greater than 50 years showed a higher risk of CVD mortality. Both the China-ASEAN FTA and Mercosur regions stand out for their successful sociodemographic transition, with a significant reduction in CVD mortality over the study period. Singapore and Brazil achieved great progress in CVD mortality reduction and the other BRICS-Plus countries should follow their lead in adopting public health policies and initiatives into practice.


Assuntos
Doenças Cardiovasculares , Sistema Cardiovascular , Adulto , Humanos , Idoso , Fatores de Risco , Fumar , Coorte de Nascimento
11.
Chem Commun (Camb) ; 59(8): 1050-1053, 2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36602378

RESUMO

An efficient nickel-catalyzed cross-coupling for the synthesis of 2-sulfonylthiazoles from readily available 2-chlorobenzothiazoles and sodium sulfinates has been developed. A variety of 2-chlorobenzothiazoles and sulfinates having a diverse range of substitution patterns can undergo the coupling process successfully at room temperature. Avoiding the use of precious catalysts and sensitive ligands, moderate to excellent yields of various 2-sulfonylthiazoles were observed.


Assuntos
Níquel , Sódio , Temperatura , Catálise , Ligantes
12.
Front Nutr ; 9: 898978, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36324616

RESUMO

Background: Unhealthy eating habits are a significant modifiable risk factor for cardiovascular diseases (CVDs); nevertheless, no evidence of their impact on the CVD burden has been reported in East Asian countries. We aimed to determine the trend and predict the future CVDs burden attributed to modifiable dietary risk factors in the East Asian countries (China, Japan, South Korea, and North Korea) and the world. Methods: The Global Burden of Disease (GBD) 2019 data were used to find the trend of CVDs [ischemic heart disease (IHD) and ischemic stroke (IS)] mortality- and disability-adjusted life-years (DALYs) attributed to dietary risk factors in the East Asian countries and the world (1990-2019) and its prediction from 2020 to 2030. We used the joinpoint regression model and the autoregressive integrated moving average (ARIMA) model for trend and future forecast, respectively. Results: From 1990 to 2019, regardless of sex, the age-standardized mortality rate (ASMR) and DALYs of IHD attributed to dietary risk factors significantly decreased in Japan, South Korea, and the world. However, the ASMR of IHD significantly increased in Chinese males and for both sexes in North Korea. The ASMR and DALYs of IHD and IS due to dietary risk factors were higher in males than in females in the world. From 2020 to 2030, the ASMR of IHD is predicted to increase in South Korean females and Japanese males. Globally, a diet low in whole grains was the top risk factor for the highest IHD mortality and DALYs in 2019, followed by a diet low in legumes and a diet high in sodium. A diet low in whole grains, a diet high in sodium, and a diet low in legumes were the leading risk factors for high IHD mortality in East Asian countries. Conclusion: The trend of IHD and IS burden due to dietary risk factors varies substantially across the East Asian countries compared to the trend of CVDs burden in the world. The study findings may help the public health policymakers to design proper strategies for improvement of the quality of life to combat the CVDs burden in the future for the East Asian countries.

13.
J Org Chem ; 87(21): 14965-14969, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36279475

RESUMO

Herein, we reported a practical and efficient strategy combining photoredox and enzyme catalysis for the construction of 3-aminoalkyl chromones from o-hydroxyaryl enaminones and N-arylglycine esters. A variety of 3-aminoalkyl chromones were synthesized with good yields under mild conditions in one pot. This synthetic protocol consists of sequential enzymatic hydrolysis and photoredox decarboxylation of N-arylglycine esters, oxidation of aminoalkyl radicals, Mannich reaction, and intramolecular nucleophilic cyclization, which affords a convenient pathway for the preparation of various 3-substituted chromones.


Assuntos
Cromonas , Ésteres , Catálise , Ciclização , Oxirredução
14.
RSC Adv ; 12(5): 2736-2740, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35425336

RESUMO

An efficient and powerful copper-assisted method for the effective conversion of a broad range of hydroxypyridines and sodium sulfinates into their corresponding pyridinyl tosylates was developed. Key features of this base- and ligand-free protocol include using the cheap and readily available CuBr2 as a medium and the use of sodium sulfinates as formal sulfonylation reagents. A variety of functional pyridinyl tosylates could be formed with good yields, which can easily be converted into C-C and C-N bond-containing compounds.

15.
Chemosphere ; 288(Pt 3): 132645, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34695483

RESUMO

A large amount of ammoniacal nitrogen wastewater discharged into the water body not only causes eutrophication and black and offensive odor in water, but also increases the difficulty and cost of water treatment, and even produces toxic effects on people and organisms. In this paper, degradation of ammoniacal nitrogen wastewater by the system of ultrasound/Mg/Al2O3/ozone (US/Mg/Al2O3/O3) was carried out. The effects of different influencing factors, such as initial pH of the solution, reaction time, temperature, catalyst addition, ozone flow rate, and ultrasonic intensity, on the degradation of ammoniacal nitrogen wastewater were investigated. The optimum reaction conditions were determined. The combination of ultrasonic technology and ozone oxidation technology can enhance the mass transfer of ozone and generate a large amount of HO. Due to Mg/Al2O3 catalyst has large surface area, the number of reactive sites and reaction molecule transport channels per unit area increases, resulting in the increase of HO on the surface, thus improving the catalytic activity. The introduction of ultrasound promotes the cleavage of N-H bonds on the catalyst surface, thereby promoting the degradation of ammoniacal nitrogen in the water. Results prove that there is not only a synergistic effect between ultrasound and catalytic ozone oxidation, but a strengthening effect of ultrasound on catalytic ozone oxidation. The research carried out in this paper provides a theoretical basis for the degradation of ammoniacal nitrogen in water.


Assuntos
Ozônio , Poluentes Químicos da Água , Purificação da Água , Catálise , Humanos , Nitrogênio , Oxirredução , Águas Residuárias/análise , Poluentes Químicos da Água/análise
16.
Eur J Pharmacol ; 907: 174296, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34224697

RESUMO

The effects and underlying mechanisms of mibefradil on gluconeogenesis and glycogenesis were investigated using insulin-resistant HepG2 human hepatocellular carcinoma cells and a mouse model of type 2 diabetes mellitus (T2DM). HepG2 cells were divided into one of four groups: control, palmitate (PA)-induced insulin-resistance (0.25 mM), low-concentration mibefradil (0.025 µM), or high-concentration mibefradil (0.05 µM). Glycogen synthesis and glucose consumption were evaluated in these HepG2 cells, and quantitative polymerase chain reaction (qPCR) and western blotting techniques were used to detect expression of forkhead box O1 (FoxO1), phosphoenolpyruvate carboxykinase (PEPCK), and glucose 6-phosphatase (G6Pase). Intracellular calcium concentrations were determined using Fluo-4 AM, and phosphorylation levels of calmodulin-dependent protein kinase II (CaMKII), protein kinase B (Akt) and FoxO1were detected by western blotting. Immunofluorescence was used for the localization and quantification of FoxO1.In vitro results were verified using a mouse model of T2DM. In HepG2 cells and mouse liver tissues, mibefradil decreased PA-induced cytoplasmic calcium levels and CaMKII phosphorylation, but increased the phosphorylation of Akt and FoxO1, thereby contributing to the cytoplasmic localization of FoxO1. Additionally, mibefradil alleviated PA-induced glucose output and insulin resistance through increased glucose consumption and glycogen synthesis, while decreasing the expression of key gluconeogenesis enzymes, including PEPCK and G6Pase. Mibefradil may help to control blood sugar levels by reducing glucose output and insulin resistance, and the mechanism of action may involve the Ca2+-CaMKII-dependent Akt/FoxO1 signaling pathway.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina , Proteínas Proto-Oncogênicas c-akt , Diabetes Mellitus Tipo 2 , Células Hep G2 , Humanos , Mibefradil
17.
J Virol ; 95(17): e0061221, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34132577

RESUMO

Cell-free and cell-to-cell spread of herpesviruses involves a core fusion apparatus comprised of the fusion protein glycoprotein B (gB) and the regulatory factor gH/gL. The human cytomegalovirus (HCMV) gH/gL/gO and gH/gL/pUL128-131 facilitate spread in different cell types. The gO and pUL128-131 components bind distinct receptors, but how the gH/gL portions of the complexes functionally compare is not understood. We previously characterized a panel of gL mutants by transient expression and showed that many were impaired for gH/gL-gB-dependent cell-cell fusion but were still able to form gH/gL/pUL128-131 and induce receptor interference. Here, the gL mutants were engineered into the HCMV BAC clones TB40/e-BAC4 (TB), TR, and Merlin (ME), which differ in their utilization of the two complexes for entry and spread. Several of the gL mutations disproportionately impacted gH/gL/gO-dependent entry and spread over gH/gL/pUL128-131 processes. The effects of some mutants could be explained by impaired gH/gL/gO assembly, but other mutants impacted gH/gL/gO function. Soluble gH/gL/gO containing the L201 mutant failed to block HCMV infection despite unimpaired binding to PDGFRα, indicating the existence of other important gH/gL/gO receptors. Another mutant (L139) enhanced the gH/gL/gO-dependent cell-free spread of TR, suggesting a "hyperactive" gH/gL/gO. Recently published crystallography and cryo-electron microscopy studies suggest structural conservation of the gH/gL underlying gH/gL/gO and gH/gL/pUL128-131. However, our data suggest important differences in the gH/gL of the two complexes and support a model in which gH/gL/gO can provide an activation signal for gB. IMPORTANCE The endemic betaherpesvirus HCMV circulates in human populations as a complex mixture of genetically distinct variants, establishes lifelong persistent infections, and causes significant disease in neonates and immunocompromised adults. This study capitalizes on our recent characterizations of three genetically distinct HCMV BAC clones to discern the functions of the envelope glycoprotein complexes gH/gL/gO and gH/gL/pUL128-13, which are promising vaccine targets that share the herpesvirus core fusion apparatus component, gH/gL. Mutations in the shared gL subunit disproportionally affected gH/gL/gO, demonstrating mechanistic differences between the two complexes, and may provide a basis for more refined evaluations of neutralizing antibodies.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/fisiologia , Glicoproteínas de Membrana/metabolismo , Mutação , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Infecções por Citomegalovirus/metabolismo , Infecções por Citomegalovirus/patologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Epiteliais/virologia , Humanos , Glicoproteínas de Membrana/genética , Mutagênese Sítio-Dirigida , Internalização do Vírus
18.
J Org Chem ; 85(23): 15062-15071, 2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-33135893

RESUMO

A new and efficient visible-light-promoted dehydrogenative cross-coupling reaction of imidazo[1,2-a]pyridines with α-amino carbonyl compounds toward imidoyl imidazo[1,2-a]pyridines is developed. A diverse range of imidazo[1,2-a]pyridines undergoes the dehydrogenative imidoylation smoothly with α-amino carbonyl compounds to access the corresponding products in satisfactory yields. We have also proposed the possible reaction mechanism based on preliminary mechanistic studies. The synthetic method has the advantages of wide substrate scope, good functional tolerance, and mild reaction conditions, which make this transformation more practical and sustainable.

19.
Bioorg Chem ; 101: 103949, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32531507

RESUMO

A one-pot efficient biocatalytic strategy for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones was developed in a circulating microwave reactor selecting α-chymotrypsin as the promiscuous biocatalyst. In the circulating reaction system, the combination of microwave heating and external cooling could avoid the denaturation and inactivation of enzyme, and greatly improved the radiation power of microwave, thus improving the specific effects of microwave. During the reaction process, the microwave radiation power was automatically adjusted by adjusting the speed of the reaction mixture circulation. When the microwave power was maintained at 110 W, the best results could be obtained with the highest yield of 96% at 55 °C in 50 min, and the reaction had a wide range of substrates. But no obvious product was detected in a tank microwave reactor at 55 °C for 100 min, under this condition, the microwave power was maintained at about 3 W. As a contrast, the reaction only obtained 63% yield in 55 °C oil bath for 96 h.


Assuntos
Reatores Biológicos , Micro-Ondas , Animais , Biocatálise , Bovinos , Quimotripsina/metabolismo
20.
J Virol ; 94(13)2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32321807

RESUMO

It is widely held that clinical isolates of human cytomegalovirus (HCMV) are highly cell associated, and mutations affecting the UL128-131 and RL13 loci that arise in culture lead to the appearance of a cell-free spread phenotype. The bacterial artificial chromosome (BAC) clone Merlin (ME) expresses abundant UL128-131, is RL13 impaired, and produces low infectivity virions in fibroblasts, whereas TB40/e (TB) and TR are low in UL128-131, are RL13 intact, and produce virions of much higher infectivity. Despite these differences, quantification of spread by flow cytometry revealed remarkably similar spread efficiencies in fibroblasts. In epithelial cells, ME spread more efficiently, consistent with robust UL128-131 expression. Strikingly, ME spread far better than did TB or TR in the presence of neutralizing antibodies on both cell types, indicating that ME is not simply deficient at cell-free spread but is particularly efficient at cell-to-cell spread, whereas TB and TR cell-to-cell spread is poor. Sonically disrupted ME-infected cells contained scant infectivity, suggesting that the efficient cell-to-cell spread mechanism of ME depends on features of the intact cells such as junctions or intracellular trafficking processes. Even when UL128-131 was transcriptionally repressed, cell-to-cell spread of ME was still more efficient than that of TB or TR. Moreover, RL13 expression comparably reduced both cell-free and cell-to-cell spread of all three strains, suggesting that it acts at a stage of assembly and/or egress common to both routes of spread. Thus, HCMV strains can be highly specialized for either for cell-free or cell-to-cell spread, and these phenotypes are determined by factors beyond the UL128-131 or RL13 loci.IMPORTANCE Both cell-free and cell-to-cell spread are likely important for the natural biology of HCMV. In culture, strains clearly differ in their capacity for cell-free spread as a result of differences in the quantity and infectivity of extracellular released progeny. However, it has been unclear whether "cell-associated" phenotypes are simply the result of poor cell-free spread or are indicative of particularly efficient cell-to-cell spread mechanisms. By measuring the kinetics of spread at early time points, we were able to show that HCMV strains can be highly specialized to either cell-free or cell-to-cell mechanisms, and this was not strictly linked the efficiency of cell-free spread. Our results provide a conceptual approach to evaluating intervention strategies for their ability to limit cell-free or cell-to-cell spread as independent processes.


Assuntos
Glicoproteínas de Membrana/genética , Proteínas do Envelope Viral/genética , Replicação Viral/genética , Linhagem Celular , Células Cultivadas , Cromossomos Artificiais Bacterianos , Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , Células Epiteliais/virologia , Fibroblastos/virologia , Citometria de Fluxo/métodos , Humanos , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutação , Proteínas do Envelope Viral/metabolismo , Vírion/metabolismo , Replicação Viral/fisiologia
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