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1.
Medicine (Baltimore) ; 98(44): e17867, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689880

RESUMO

Glycogen storage disease (GSD) type IX, characterized by liver enlargement and elevated aminotransferase levels, is the most frequent type of GSD. The global incidence of GSD type IXa is only about 1/100,000 individuals. Case reports of GSD type IX are rare in China. We present the first case report of GSD type IXa in Northeast China caused by mutation of PHKA2.An 11-year-old boy was referred to our hospital because of liver enlargement with consistently elevated transaminase levels over 6 months.Histopathological results following an ultrasound-guided liver biopsy confirmed a diagnosis of GSD. Further genetic testing showed that the patient had GSD type IXa caused by the c.133C>T mutation in PHAK2.We placed the patient on a high-protein and high-starch diet and provided hepatoprotective and supportive therapy.The patient's transaminase levels decreased significantly and were nearly normal at 10-month follow-up.This is the first reported case of GSD type IXa in Northeast China. We hope that the detailed and complete report of this case will provide a reference for the diagnosis of liver enlargement of unknown etiology in future clinical practice.


Assuntos
Carcinoma Hepatocelular/virologia , Hepatite B Crônica/genética , Interleucinas/genética , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , Polimorfismo de Nucleotídeo Único , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Grupo com Ancestrais do Continente Asiático/genética , Carcinoma Hepatocelular/genética , Estudos de Casos e Controles , Progressão da Doença , Feminino , Hepatite B Crônica/complicações , Humanos , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Mutação Puntual , Estudos Retrospectivos , Fumar/efeitos adversos
2.
BMC Cardiovasc Disord ; 19(1): 244, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694566

RESUMO

BACKGROUND: The independent association of neck circumference (NC) on elevated blood pressure is still uncertain in adults of China. The aim of this study is to explore such association and investigate the predictive value of NC on hypertension. METHODS: A total of 4279 adults aged 20-80 years participated in the cross-sectional study in 2014. Anthropometric information, NC, body composition indexes such as waist circumference, hip circumference and body fat percentage, and blood pressure were measured. General linear regression model was used to explore the association between NC and blood pressure; Logistic regression models were fitted to calculate the multi-variable adjusted prevalence, and the association of NC with hypertension. RESULTS: The overall prevalence of hypertension and pre-hypertension were 11.05 and 23.63%, respectively. NC was positively associated with both SBP and DBP (p < 0.001). The adjusted prevalence of hypertension increased with elevated NC quartiles in both sexes (p for trend < 0.001), from 17.81 to 42.93% in male and 9.72 to 21.31% in female. For male, NC was only associated with hypertension (OR: 1.15, 95% CI: 1.05-1.25) but not with pre-hypertension (OR: 0.97, 95% CI: 0.88-1.06). However, in female, NC was associated with both pre-hypertension and hypertension, the BMI adjusted ORs were 1.15 (1.03-1.28) and 1.24 (1.14-1.34). The sex-specific AUCs for NC predicting hypertension were 0.633 in male and 0.663 in female, similar with AUCs of other body fat indexes. CONCLUSIONS: NC was associated with both pre-HTN and HTN independent from other body composition indexes. NC is a simple and useful anthropometric index to identify elevated blood pressure in Chinese adults.

3.
Cancer Med ; 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31709750

RESUMO

BACKGROUND: Early detection of urothelial carcinoma (UC) by noninvasive diagnostic methods with high accuracy is still underscored. This study aimed to develop a noninvasive assay incorporating both enrichment of urine exfoliated cells and immunoassays for UC detection. METHODS: Polystyrene dishes were exposed to oxygen plasma and modified with 3-aminopropyltriethoxysilane to prepare amine-functionalized nanostructured substrates (NS). Performance characterization of NS was evaluated by atomic force microscope and X-ray photoelectron spectroscopy. Urine exfoliated cells were captured by NS and then immunostained to detect urinary tumor cells (UTCs), which was called UTC assay. The receiver operating characteristic (ROC) curve, area under ROC curve (AUC), and Youden index were used to find the cutoff value of UTC assay. ROC analysis and McNemar test were used to compare the diagnostic accuracy of UTC assay with cytology. Kappa test was used to analyze the agreement of UTC assay and cytology with pathological diagnosis. RESULTS: Nanostructured substrates had good cell binding yields of nucleated cells and tumor cells. CK20+ CD45- CD11b- cells were considered as UTCs. UTC number ≥ 1 per sample could be considered as a positive result. By AUC and Kappa analysis, UTC assay showed good performance in UC detection. McNemar test demonstrated that UTC assay had a superior sensitivity even in low-grade subgroup and a similar specificity compared to cytology in UC diagnosis. CONCLUSIONS: Nanostructured substrates could be used to enrich the exfoliated cells from urine samples. UTC assay with NS has the potential to play a role in UC detection. The value of this assay still needs additional validation by large, multi-center studies.

4.
Chemosphere ; 241: 125013, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31604199

RESUMO

In this study, we investigated the phytotoxicity of an imidazolium-based ionic liquid, 1-allyl-3-methylimidazolium chloride ([Amim]Cl), against maize seedlings. It was found that in response to an increase in [Amim]Cl treatment concentrations, there were significant decreases in growth parameters (fresh weights and lengths) and the photosynthetic pigment contents of maize plants, whereas in contrast, the malondialdehyde content increased. In order to determine the molecular basis of [Amim]Cl-induced plant growth inhibition, an RNA-Seq analysis to examine the gene expression profiles of selected central biological pathways was performed. And a total of 4024 genes that were differentially expressed between control and 400 mg/L [Amim]Cl-treated plants were accordingly identified. Pathway enrichment analysis for the differentially expressed genes revealed that 12 of 15 genes in the porphyrin and chlorophyll metabolic pathways were down-regulated in response to [Amim]Cl treatment. Moreover, all six genes encoding key chlorophyll synthetic enzymes were down-regulated by [Amim]Cl. With regards to plant hormone metabolic pathways, the genes encoding key enzymes involved in ethybilene and abscisic acid (ABA) biosynthesis were up-regulated in response to [Amim]Cl treatment. Genes responsible for gibberellin (GA) inactivation were also stimulated by [Amim]Cl. These observations indicate that [Amim]Cl may promote the biosynthesis of senescence-related hormones (ethylene and ABA) as well as inactivation of growth-promoting hormones (GAs). It might be concluded that the observed [Amim]Cl-induced inhibition of maize seedling growth could be associated with changes in the gene expression profiles of these metabolic pathways.

5.
Life Sci ; 238: 116962, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31628913

RESUMO

AIMS: Electroacupuncture (EAc) has a pulmonary protective effect during cardiopulmonary bypass (CPB), but its molecular mechanisms including inflammasome activation signaling pathways remains unclear. MATERIALS AND METHODS: Male Sprague Dawley rats were divided into control, CPB + EAc and CPB groups. Lung injury model was developed by CPB treatment and EAc (2/100 Hz) was carried out before CPB in the CPB + EAc group. Lung tissues were collected at two time points (0.5 h; 2 h) to determine cytokines release by ELISA kits, and protein expressions by Western blot. Serum collected at two time points (0.5 h; 2 h) from CPB and CPB + EAc treated groups were used in NR8383 cells to confirm the effect of EAc. KEY FINDINGS: CPB significantly increased the inflammatory mediators, histological damage and expression of inflammasome related protein and apoptosis, when compared with control group. The level of tumor necrosis factor-α(TNF-α), interleukin (IL)-18 and IL-1ß in the CPB + EAc treated group was significantly decreased along with histological changes compared to CPB. Moreover, EAc inhibited the activation of Nod like receptor protein-3 (NLRP3) inflammasome complex, caspase-8 and activated NF-E2-related factor 2 (p-Nrf2). In addition, serum from the CPB + EAc group prevented CPB induced activation of inflammasome and related mediators, reducing ROS generation and apoptosis in NR8383 macrophages. SIGNIFICANCE: These findings indicate that EAc had a critical anti-apoptotic role by suppression of ROS/Nrf2/NLRP3 inflammasome pathway. EAc might be a possible therapeutic treatment for CPB-induced acute lung injury.

6.
Plant Physiol Biochem ; 142: 415-428, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31416008

RESUMO

The variation of flower color of chrysanthemum (Chrysanthemum×morifolium) is extremely rich, and carotenoids, which are mainly stored in the plastid, are important pigments that determine the color of chrysanthemum. However, the genetic regulation of the carotenoid metabolism pathway in this species still remains unclear. In this study, a pink chrysanthemum cultivar, 'Jianliuxiang Pink', and its three bud sport mutants (including white, yellow and red color mutants, 'Jianliuxiang White', 'Jianliuxiang Yellow' and 'Jianliuxiang Red', respectively) were used as experimental materials to analyze the dynamic changes of carotenoid components and plastid ultrastructure at different developmental stages of ray florets. We found that the carotenoid components and plastid ultrastructure of the four color cultivars in the early developmental stage of the chrysanthemum capitulum (S1) were almost identical, and the carotenoids mainly included violaxanthin, lutein and ß-carotene, which exist in proplastids and immature chloroplasts. With the development of capitulum, the chloroplasts in 'Jianliuxiang White' and 'Jianliuxiang Pink' were degraded, and the protoplasts did not transform but rather formed vesicles that accumulated trace amounts of carotenoids. The proplastids and chloroplasts in 'Jianliuxiang Yellow' and 'Jianliuxiang Red' were all transformed into chromoplasts and consist of lutein as well as lutein's isomer and derivatives. Using comparative transcriptomics combined with gene expression analysis, we found that CmPg-1, CmPAP10, and CmPAP13, which were involved in chromoplast transformation, CmLCYE, which was involved in carotenoid biosynthesis, and CmCCD4a-2, which was involved in carotenoid degradation, were differentially expressed between four cultivars, and these key genes therefore should affect the accumulation of carotenoids in chrysanthemum. In addition, six transcription factors, CmMYB305, CmMYB29, CmRAD3, CmbZIP61, CmAGL24, CmNAC1, were screened using weighted gene co-expression correlation network analysis (WGCNA) combined with correlative analysis to determine whether they play an important role in carotenoid accumulation by regulating structural genes related to the carotenoid metabolism pathway and plastid development. This study analyzed dynamic changes of carotenoid components and plastid ultrastructure of the four bud mutation cultivars of chrysanthemum and identified structural genes and transcription factors that may be involved in carotenoid accumulation. The above results laid a solid foundation for further analysis of the regulatory mechanism of the carotenoid biosynthesis pathway in chrysanthemum.

7.
Sheng Wu Gong Cheng Xue Bao ; 35(8): 1500-1510, 2019 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-31441621

RESUMO

MarR family transcription regulators are ubiquitous among bacteria and archaea. They extensively control multiple cellular processes and elaborately regulate the expression of genes involved in virulence, stress response and antibiotics at translational level. In Xanthomonas campestris pv. campestris, insertional inactivation of MarR family transcription regulator HpaR (XC2827) resulted in significantly decrease in virulence and increase in the production of the extracellular proteases. Here, we reported that the genome of Xcc 8004 encodes nine MarR family transcription regulators. The MarR family transcription regulators, HpaR (XC2827) and XC0449, were heterologous expressed and purified. In vitro MST and Pull-down assay confirmed the physical interaction between HpaR and XC0449. Phenotypical assay determined that deletion of XC0449 resulted in substantial virulence attenuation. In vitro EMSA, in vivo qRT-PCR and GUS activity assay identified that HpaR and XC0449 coordinately act as the transcriptional activator to regulate the expression of the virulence-associated gene XC0705, and eventually control the bacterial virulence and the production of extracellular proteases.


Assuntos
Xanthomonas campestris , Proteínas de Bactérias , Regulação Bacteriana da Expressão Gênica , Fatores de Transcrição , Virulência
8.
Org Lett ; 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31436436

RESUMO

A highly chemoselective and regioselective copper-catalyzed radical cyanoperfluoroalkylation of alkynes is described. This three-component reaction directly uses commercially available alkynes, perfluoroalkyl iodides, and trimethylsilyl cyanide as the reaction partners and delivers a variety of perfluoroalkylated cyanoalkenes in good yields. Broad substrate scope and good functional group tolerance are observed. The perfluoroalkylated cyanoalkenes that are produced can be readily transformed into useful fluoroalkylated derivatives.

9.
Carbohydr Polym ; 219: 162-171, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151513

RESUMO

Rheological behaviors of microbial polysaccharides with different substituents in aqueous solutions have been systematically investigated. Both the saccharide side chains and acetyl substituents improve the gelation of welan gum (WG), diutan gum (DG) and gellan gum (GG) in pure water at 25 °C. For the polysaccharides with saccharide side chains (WG and DG), the relationship between the apparent viscosity and concentration conforms to the linear equation, while that of the polysaccharide with acetyl (GG) is exponential. More importantly, the roles of substituents on the stability of the molecular conformation of polysaccharides are significantly depended on the surrounding environment. Disaccharide side chains promote the stability of helical conformation and gel aggregates of GG at high temperature (85 °C) or in the presence of inorganic salts with the ionic strength of 2.0 mol L-1. The stability of gel structure containing acetyl (GG) shows higher temperature/salt sensitivity. Additionally, deacylated gellan gum (GG(d)) solutions transform into hydrogels in the presence of dodecyltrimethylammonium bromide (DTAB). This study will help to obtain a better understanding on the rheological properties of polysaccharides with respect to the conformation and applications.


Assuntos
Bactérias/metabolismo , Hidrogéis/química , Polissacarídeos Bacterianos/química , Reologia , Tensoativos/química , Ácido Acético/química , Concentração Osmolar , Sais/química , Soluções/química , Temperatura Ambiente , Viscosidade
10.
Aust J Prim Health ; 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31196378

RESUMO

The study aimed to explore the independent association between expanded normal weight obesity categories and blood pressure among adults aged 20-80 years in China. By cross-sectional design, a total of 4279 adults living in Shaanxi Province, China, were selected from communities via multi-stage stratified cluster sampling in 2014. Information on anthropometric, body composition and blood pressure was collected and analysed. Expanded normal weight obesity (ENWO) categories were used to identify the level of bodyweight based on the combination of body mass index (BMI) and body fat percentage (BFP) categories. The age- and sex-standardised prevalence of hypertension increased within ENWO groups, from 10.12% in the underweight-low body fat group to 45.92% in the obesity-high body fat group. In under or normal weight participants, body fat percentage was found independently associated with hypertension in men, with an adjusted odds ratio of 3.69 in the fourth quartile of BFP compared with the first one. However, this effect was not observed in women. BFP was independently associated with increased risk of hypertension, especially in men. People with normal BMI should be re-identified as a high-risk population based on BFP level when it comes to hypertension prevention in primary healthcare settings.

12.
Cell Death Dis ; 10(6): 405, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31138777

RESUMO

Hepatitis B virus-encoded X protein (HBx) acts as a tumor promoter during hepatocellular carcinoma (HCC) development, probably by regulating the expression of host proteins through protein-protein interaction. A proteomics approach was used to identify HBx-interacting proteins involved in HBx-induced hepatocarcinogenesis. We validated the proteomics findings by co-immunoprecipitation and confocal microscopy. We performed cell proliferation, migration assays and cell cycle analyses in HCC cells. Finally, we confirmed the clinical significance of our findings in samples from patients. We found that cortactin (CTTN) is a novel HBx-interacting protein, and HBx regulates the expression of CTTN in the HCC cell lines MHCC-LM3 and HepG2. Mechanistically, by upregulating the expression of cAMP response element-binding protein (CREB1) and its downstream targets, such as cyclin D1 and MMP-9, the effects of the HBx-CTTN interaction on the enhancement of cellular proliferation and migration were maintained by inhibiting cell cycle arrest. In addition, we demonstrated that the levels of CTTN and CREB1 were closely correlated in clinical samples from HBV-infected patients with HCC. Overall, our data suggests that HBx contributes to cell migration and proliferation of HCC cells by interacting with CTTN and regulating the expression of CTTN and CREB1. Therefore, the HBx/CTTN/CREB1 axis is a potential novel therapeutic target in HCC.

13.
Biomed Pharmacother ; 115: 108816, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31096144

RESUMO

OBJECTIVE: Inflammation and immune responses are crucial factors associated with the onset and progression of stroke. Interleukin-11 (IL-11) is a hematopoietic IL-6 family cytokine that functions as an anti-inflammatory agent against various inflammatory diseases. However, its roles in stroke remain unknown. In this study, we investigated the effects of IL-11 on cerebral ischemia-reperfusion injury in a model of focal cerebral ischemia. METHODS: Mice were randomly divided into five groups the vehicle group, the middle cerebral artery occlusion (MCAO) group, the MCAO plus adenosine monophosphate-activated protein kinase (AMPK) inhibitor compound C group, the MCAO plus IL-11 treatment group, and the MCAO plus IL-11 treatment and compound C group. Focal cerebral ischemia was induced by occluding the left middle cerebral artery, and reperfusion was achieved by withdrawing the suture 2 h after ischemia. The protein expression levels of IL-11 were measured using Western blot analysis, and its location was detected using immunohistochemistry and immunofluorescence staining. The infarct volume was examined using 2,3,5-triphenyl tetrazolium chloride (TTC) staining, and the neurobehavioral progression was assessed using the neurological scoring system. The expression of astrocytes and microglia was detected using immunochemistry, and real-time quantitative PCR was used for the gene quantification of inflammatory cytokines. The extent of cerebral ischemia-reperfusion injury was tested using Nissl staining and the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay. The expression of the apoptotic proteins Bax, Bcl-2 and cleaved caspase-3 were detected using Western blot analysis, and the oxidative stress was also measured. RESULTS: The expression of IL-11 mRNA and protein significantly decreased after cerebral ischemia. Immunohistochemical staining showed a large amount of IL-11 in the cerebral cortex of the mice in the vehicle group, whereas the immunoreactivity of IL-11 remained weak for 24 h in the MCAO group. Immunofluorescent staining further confirmed that IL-11 was mainly expressed in the neurons. It was suggested that IL-11 (20 µg/kg) treatment ameliorated infarction and reduced neurological scores. In addition, IL-11 proved to reduce neuropathic damage, glial activation, and the expression of proinflammatory cytokines and increase the expression of anti-inflammatory cytokines after cerebral ischemia. IL-11 was also able to alleviate oxidative stress caused by cerebral ischemia, and AMPK inhibition enhanced the alleviation. Moreover, IL-11 was found to inhibit apoptosis caused by cerebral ischemia, which could also be facilitated by AMPK inhibitors. SIGNIFICANCE: Our research suggests that IL-11 is decreased during cerebral ischemia-reperfusion injury, but IL-11 treatment can improve neurological function and reduce the cerebral infarct volume, which can trigger stroke in mice. AMPK inhibition can further promote the protective effect of IL-11 in stroke. Overall, we demonstrate that IL-11 is of therapeutic interest in controlling stroke and managing cerebral ischemia-reperfusion injury.

14.
Artigo em Inglês | MEDLINE | ID: mdl-30825869

RESUMO

The effects of substituent X and Y on ultraviolet (UV) absorption properties of stilbene compounds XPhCHCHPhY (XSBY) were studied both experimentally and computationally from the viewpoint of UV maximum absorption wavelength (λmax) and the corresponding energy (υmax). In the studies, the contribution of substituents on υmax shift was explored. The results show that with increase of electron withdrawing or electron donating ability of X or Y, there is an enhanced electron delocalization of XSBY that leads to bathochromic shift. Computational analyses based on density functional theory were conducted to elucidate the phenomena. It is disclosed that the υmax values are significantly affected by the excited state, though the electronic effect of ground state cannot be ignored. Finally, on the basis of the respective influences of X and Y, a quantitative model, which was proved reliable by the leave-one-out method, was developed to scale the effects of terminal substituents on υmax. According to the model, the effects of substituents X or Y exhibit almost the same action on υmax owing to the symmetric skeleton of the XSBY compounds. The findings provide deep insight into the effects of terminal substituents on UV absorption properties of stilbene compounds, and the derived model enables practical expression of the relationship between substituents and UV absorption.

15.
Appl Microbiol Biotechnol ; 103(7): 3099-3109, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30788541

RESUMO

Cupriavidus basilensis WS degrades diphenyl ether (DE) and its lower brominated derivatives using enzymes encoded by the bph operon. However, it is not yet known under what circumstances bph genes are expressed and how they are regulated in C. basilensis WS. To answer these questions, we used transposon mutagenesis and identified a new two-component regulatory system, BphS/BphT, in C. basilensis WS, which is indispensable for the expression of the bph operon. When BphS or BphT is inactivated, C. basilensis WS no longer exhibits the ability to decompose DE. Using a ß-galactosidase reporter system and RT-qPCR, we showed that bph genes are constitutively transcribed in C. basilensis WS and that deletion of bphS or bphT strongly inhibited the transcription of bph genes. We also showed that the gene ORF0, which is upstream of bphA1 and is similar to the GntR-family regulators of the bph operon, is not involved in the constitutive transcription of the bph operon in C. basilensis WS. The cis-acting elements required for the expression and regulation of bph genes in the DE degradation pathway are included in the intergenic region between ORF0 and bphA1. Our results suggest that BphS/BphT represents a new two-component regulatory system for the bph operon that is necessary for the constitutive expression of bph genes.


Assuntos
Proteínas de Bactérias/genética , Cupriavidus/genética , Regulação Bacteriana da Expressão Gênica , Mutagênese , Óperon , Elementos de DNA Transponíveis , DNA Intergênico , Éteres Fenílicos/metabolismo , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase em Tempo Real , Sequências Reguladoras de Ácido Nucleico , Transcrição Genética , beta-Galactosidase/genética
16.
Plant Physiol Biochem ; 135: 304-309, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30599307

RESUMO

Drought stress during reproductive growth stages greatly affects the growth and productivity of maize plants. To better understand the metabolic regulation during post-silking drought (PD) stress, an RNA sequencing (RNA-Seq) analysis was performed at the late stage of leaf senescence in maize. Physiological measurements showed that PD stress reduced both leaf carbon and nitrogen levels. A total of 4013 differentially expressed genes (DEGs) were found based on RNA-Seq analysis, 115 of which were identified to be involved in photosynthesis and in the metabolism of sucrose, starch, and amino acids. Among these DEGs, 14 genes involved in photosynthesis were down-regulated. The genes coding for sucrose and pectin synthesis were up-regulated under PD stress. The two genes of asparagine synthetase (ZmAS3 and ZmAS4), which are responsible for nitrogen remobilization in leaves, were also significantly induced by the drought treatment. The expression profiles of these genes involved in carbon and nitrogen metabolism suggests their regulatory roles during drought-induced leaf senescence.


Assuntos
Carbono/metabolismo , Nitrogênio/metabolismo , Folhas de Planta/metabolismo , Zea mays/metabolismo , Desidratação , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Fotossíntese , Folhas de Planta/crescimento & desenvolvimento , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA , Transcriptoma , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/fisiologia
17.
Org Lett ; 21(3): 776-779, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668128

RESUMO

An iron(II)-catalyzed radical alkyl Heck-type reaction of alkyl iodides with vinylarenes under mild conditions has been reported. t-Butyl peroxybenzoate (TBPB) behaves simultaneously as a radical relay initiator, a precursor for the generation of alkyl radical from alkyl iodides, and an oxidant to recycle iron(II)/iron(III). Unactivated primary, secondary, and tertiary alkyl iodides are compatible with the reaction conditions. The mechanistic studies suggest that a radical-polar-crossover pathway might be involved in the catalytic cycle.

18.
Nat Commun ; 10(1): 122, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30631054

RESUMO

Carboazidation of alkenes and alkynes holds the promise to construct valuable molecules directly from chemical feedstock therefore is significantly important. Although a few examples have been developed, there are still some unsolved problems and lack of universal methods for carboazidation of both alkenes and alkynes. Here we describe an iron-catalyzed rapid carboazidation of alkenes and alkynes, enabled by the oxidative radical relay precursor t-butyl perbenzoate. This strategy enjoys success with a broad scope of alkenes under mild conditions, and it can also work with aryl alkynes which are challenging substrates for carboazidation. A large number of diverse structures, including many kinds of amino acid precursors, fluoroalkylated vinyl azides, other specific organoazides, and 2H-azirines can be easily produced.

19.
J Cell Biochem ; 120(6): 10273-10280, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30556310

RESUMO

BACKGROUND: This study aimed to identify factors that affect the prognosis of budesonide therapy for Crohn's disease patients. METHOD: Change in Crohn's disease activity index (CDAI) scores at latest follow-up after budesonide therapy reported by individual studies were pooled to gain overall effect size under random effects model and then metaregression analyses were performed to identify factors affecting the change in CDAI scores after budesonide treatment. RESULTS: Fifteen studies (1875 patients; age, 35.6 years [95% confidence interval (CI): 34.1, 37.0]; 41.66% [95% CI: 37.44, 45.88] males; 33.3% [95% CI: 24.3, 42.3] smokers; weight, 64.7 kg [95% CI: 62.71 66.6] and height, 168 cm [95% CI: 165, 171]) were included. Disease duration was 7.0 years [95% CI: 5.7, 8.2] and duration of the current episode was 3.1 months [95% CI: 1.7, 4.4]. Proportion of patients with prior resection was 42% [95% CI: 34%, 50%]. The disease was 21% in the ileum, 61% in ileocecum, and 18% in the colon. Budesonide dose was 8.83 mg/d [95% CI: 7.52, 10.14]. In a follow-up duration of 21.0 weeks [95% CI: 15.2, 26.8], budesonide treatment was associated with improvement in CDAI score of -117.8 [95% CI: -134.0, -102.0]. The magnitude of the change in CDAI score at the latest follow-up was significantly inversely associated with the percentage of smokers, but positively associated with the baseline CDAI score and duration of the current episode. CONCLUSION: Budesonide therapy to Crohn's disease patients appears to be more effective in patients with the more serious condition. Smoking may also affect the prognosis.

20.
Org Lett ; 21(1): 261-265, 2019 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-30582704

RESUMO

A general oxyalkylation of terminal alkynes enabled by iron catalysis has been developed. Primary and secondary alkyl iodides acted as the alkylating reagents and afforded a range of α-alkylated ketones under mild reaction conditions. Acetyl tert-butyl peroxide (TBPA) was used as the radical relay precursor, providing the initiated methyl radical to start the radical relay process. Preliminary mechanistic studies were conducted, and late-stage functionalizations of natural product derivatives were performed.

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