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1.
Nature ; 591(7848): 147-151, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33505025

RESUMEN

Many sequence variants have been linked to complex human traits and diseases1, but deciphering their biological functions remains challenging, as most of them reside in noncoding DNA. Here we have systematically assessed the binding of 270 human transcription factors to 95,886 noncoding variants in the human genome using an ultra-high-throughput multiplex protein-DNA binding assay, termed single-nucleotide polymorphism evaluation by systematic evolution of ligands by exponential enrichment (SNP-SELEX). The resulting 828 million measurements of transcription factor-DNA interactions enable estimation of the relative affinity of these transcription factors to each variant in vitro and evaluation of the current methods to predict the effects of noncoding variants on transcription factor binding. We show that the position weight matrices of most transcription factors lack sufficient predictive power, whereas the support vector machine combined with the gapped k-mer representation show much improved performance, when assessed on results from independent SNP-SELEX experiments involving a new set of 61,020 sequence variants. We report highly predictive models for 94 human transcription factors and demonstrate their utility in genome-wide association studies and understanding of the molecular pathways involved in diverse human traits and diseases.


Asunto(s)
Polimorfismo de Nucleótido Simple/genética , Técnica SELEX de Producción de Aptámeros , Máquina de Vectores de Soporte , Factores de Transcripción/metabolismo , Sitios de Unión/genética , Enfermedad/genética , Genoma Humano/genética , Humanos , Ligandos , Unión Proteica
2.
Small ; 20(7): e2306135, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37803439

RESUMEN

Biofilm is a spatially organized community formed by the accumulation of both microorganisms and their secretions, leading to persistent and chronic infections because of high resistance toward conventional antibiotics. In view of the tunable physicochemical properties and the related unique biological behavior (e.g., size-, shape-, and surface charge-dependent penetration, protein corona endowed targeting, catalytic- and electronic-related oxidative stress, optical- and magnetic-associated hyperthermia, etc.), nanomaterials-based therapeutics are widely used for the treatment of biofilm-associated infections. In this review, the biological characteristics of biofilm are introduced. And the nanomaterials-based antibacterial strategies are further discussed via biofilm targeting, including preventing biofilm formation, enhancing biofilm penetration, disrupting the mature biofilm, and acting as drug delivery systems. In which, the interactions between biofilm and nanomaterials include mechanical disruption, electron transfer, enzymatic degradation, oxidative stress, and hyperthermia. Additionally, the current advances of nanomaterials for antibacterial nanomaterials by biofilm targeting are summarized. This review aims to present a complete vision of antibacterial nanomaterials-biofilm (nano-bio) interactions, paving the way for the future development and clinical translation of effective antibacterial nanomedicines.


Asunto(s)
Nanoestructuras , Nanoestructuras/química , Antibacterianos/química , Biopelículas , Nanomedicina , Sistemas de Liberación de Medicamentos
3.
Nat Methods ; 17(7): 685-688, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32572232

RESUMEN

We have developed CRISPR-assisted RNA-protein interaction detection method (CARPID), which leverages CRISPR-CasRx-based RNA targeting and proximity labeling to identify binding proteins of specific long non-coding RNAs (lncRNAs) in the native cellular context. We applied CARPID to the nuclear lncRNA XIST, and it captured a list of known interacting proteins and multiple previously uncharacterized binding proteins. We generalized CARPID to explore binders of the lncRNAs DANCR and MALAT1, revealing the method's wide applicability in identifying RNA-binding proteins.


Asunto(s)
Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ARN/metabolismo , Animales , Proteínas de Unión al ADN/metabolismo , Células HEK293 , Humanos , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Factores de Transcripción/metabolismo
4.
Opt Lett ; 48(23): 6240-6243, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38039236

RESUMEN

A magnetic field (MF) sensor with a stable structure and high sensitivity has been proposed and experimentally verified. We used the water bath method to produce a layer of Fe2O3 nanorods on a tapered few mode fiber (FMF) surface to form a Mach-Zehnder interferometer (MZI). The experiment found that the nanostructure produced on the surface of FMF were particularly stable and firm. Under the action of an external MF, the magnetic permeability of a Fe2O3 nanorod will change, leading to a change in its refractive index, resulting in a linear shift in the resonance wavelength of MZI. The experimental results showed that the MF sensitivity of MZI reached -0.5348 nm/mT in 10 mT∼80 mT. In addition, MZI has a certain sensitivity to environmental humidity and temperature. A long-period fiber grating and a fiber Bragg grating are cascaded with MZI to achieve a simultaneous measurement of three quantities and eliminate their cross-sensitivity.

5.
BMC Cancer ; 22(1): 1181, 2022 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-36384536

RESUMEN

BACKGROUND: Repair pathway genes play an important role in the development of lung cancer. The study aimed to assess the correlation between single nucleotide polymorphisms (SNPs) in DNA repair gene (GTF2H1 and RAD54L2) and the risk of lung cancer. METHODS: Five SNPs in GTF2H1 and four SNPs in RAD54L2 in 506 patients with lung cancer and 510 age-and gender-matched healthy controls were genotyped via the Agena MassARRAY platform. The influence of GTF2H1 and RAD54L2 polymorphisms on lung cancer susceptibility was assessed using logistic regression analysis by calculating odds ratios (ORs) and their corresponding 95% confidence intervals (CIs). RESULTS: RAD54L2 rs9864693 GC genotype increased the risk of lung cancer (OR = 1.33, 95%CI: 1.01-1.77, p = 0.045). Stratified analysis found that associations of RAD54L2 rs11720298, RAD54L2 rs4687592, RAD54L2 rs9864693 and GTF2H1 rs4150667 with lung cancer risk were found in subjects aged ≤ 59 years. Precisely, a protective effect of RAD54L2 rs11720298 on the occurrence of lung cancer was observed in non-smokers and drinkers. GTF2H1 rs4150667 was associated with a decreased risk of lung cancer in subjects with BMI ≤ 24 kg/m2. RAD54L2 rs4687592 was associated with an increased risk of lung cancer in drinkers. In addition, GTF2H1 rs3802967 was associated with a reduced risk of lung squamous cell carcinoma. CONCLUSION: Our study first revealed that RAD54L2 rs9864693 was associated with an increased risk of lung cancer in the Chinese Han population. This study may increase the understanding of the effect of RAD54L2 and GTF2H1 polymorphisms on lung cancer occurrence.


Asunto(s)
ADN Helicasas , Predisposición Genética a la Enfermedad , Neoplasias Pulmonares , Factor de Transcripción TFIIH , Humanos , Pueblo Asiatico/genética , China/epidemiología , Neoplasias Pulmonares/epidemiología , Neoplasias Pulmonares/genética , Polimorfismo de Nucleótido Simple , Factor de Transcripción TFIIH/genética , ADN Helicasas/genética
6.
Int J Mol Sci ; 23(19)2022 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-36232590

RESUMEN

Skin wound repair remains a major challenge in clinical care, and various strategies have been employed to improve the repair process. Recently, it has been reported that macrophages are important for the regeneration of various tissues and organs. However, their influence on wound repair is unclear. Here, we aimed to explore whether macrophages would participate in the wound healing process and to explore new possibilities of treatment for skin defects. We firstly created a mouse full-thickness skin defect model to observe the distribution of macrophages in the regenerating tissue and then detected the influence of macrophages on skin defect repair in both macrophage-depletion and macrophage-mobilization models. We found that the number of macrophages increased significantly after skin defect and persisted during the process of wound repair. The regeneration process was significantly prolonged in macrophage-depleted animals. RT-qPCR and ELISA assays further demonstrated that the expression of growth factors was perturbed in the regenerating tissue. The activation of macrophages by granulocyte-macrophage colony-stimulating factor (GM-CSF) injection could significantly improve wound healing, accompanied with an upregulation of the expression of various growth factors. In conclusion, the current study demonstrated that macrophages are critical for skin regeneration and that GM-CSF exhibited therapeutic potential for wound healing.


Asunto(s)
Factor Estimulante de Colonias de Granulocitos y Macrófagos , Cicatrización de Heridas , Animales , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Recuento de Leucocitos , Macrófagos/metabolismo , Ratones , Piel/metabolismo , Cicatrización de Heridas/fisiología
7.
Semin Cancer Biol ; 67(Pt 1): 49-56, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-31473269

RESUMEN

The sex-determining region Y-box 7 (Sox7) is an important member of the SOX F family, which is characterized by a high-mobility-group DNA-binding domain. Previous studies have demonstrated the role of SOX7 in cardiovascular development. SOX7 expression could be detected in normal adult tissues. Furthermore, the expression levels of SOX7 were different in different tumors. Most studies showed the downregulation of SOX7 in tumors, while some studies reported its upregulation in tumors. In this review, we first summarized the upstream regulators (including transcription factors, microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and some exogenous regulators) and downstream molecules (including factors in the Wnt/ß-catenin signaling pathway and some other signaling pathways) of SOX7. Then, the roles of SOX7 in multiple tumors were presented. Finally, the significance of divergent SOX7 expression during cardiovascular development was briefly discussed. The information compiled in this study characterized SOX7 during tumorigenesis and cardiovascular development, which should facilitate the design of future research and promote SOX7 as a therapeutic target.


Asunto(s)
Carcinogénesis , Enfermedades Cardiovasculares/patología , Biología Evolutiva , Neoplasias/patología , Factores de Transcripción SOXF/metabolismo , Animales , Enfermedades Cardiovasculares/genética , Enfermedades Cardiovasculares/metabolismo , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Factores de Transcripción SOXF/genética , Transducción de Señal
8.
Chemistry ; 26(9): 1953-1957, 2020 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-31804734

RESUMEN

A novel strategy for 1,2-dihalogenation of alkenes is reported that occurs through a sequential nucleophilic halide addition and electrophilic halogenation. By trapping the in situ generated unstable α-trifluoromethyl carbanion intermediates derived from the nucleophilic fluoride addition to electron-poor gem-difluoroalkenes, this fluorohalogenation of gem-difluoroalkenes with electrophilic haloalkynes affords various useful α-trifluoromethyl halides in high yields. A pesticidal active compound and various attractive trifluromethylated molecules could be smoothly synthesized from these obtained α-trifluoromethyl halides.

9.
Semin Cancer Biol ; 50: 1-12, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29719213

RESUMEN

Forkhead box O (FOXO) family has recently been highlighted as important transcriptional regulators associated with many diverse carcinomas. Although redundant functionality between FOXO family members with cancer is known, regulatory ability of FOXO4 for tumorigenesis and tumor metastasis is still on the way. FOXO4 significantly regulates cell cycle, resists oxidative stress, and responses to hypoxia. FOXO4 alteration is closely linked to the progression of human cancer. In this review, we introduce the regulation of FOXO4 in physiological and pathological conditions. Particularly, the pathophysiological processes and molecular pathways regulated by FOXO4 in the development and progression of cancer are also summarized. Moreover, whether FOXO4 acts as a tumor-suppressor or pro-tumoral factor in tumors and the potential directions of future FOXO4 research are discussed. The information reviewed here may assist in the experimental design and increase the potential of FOXO4 as a therapeutic target for cancer.


Asunto(s)
Carcinogénesis/genética , Neoplasias/genética , Factores de Transcripción/genética , Proteínas de Ciclo Celular , Factores de Transcripción Forkhead , Genes Supresores de Tumor , Humanos , Neoplasias/patología , Estrés Oxidativo/genética , Hipoxia Tumoral/genética
10.
Semin Cancer Biol ; 50: 21-31, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29427645

RESUMEN

The epithelial-mesenchymal transition (EMT) is an acknowledged cellular transition process in which epithelial cells acquire mesenchymal-like properties that endow cancer cells with increased migratory and invasive behavior. Forkhead box O (FOXO) proteins have been shown to orchestrate multiple EMT-associated pathways and EMT-related transcription factors (EMT-TFs), thereby modulating the EMT process. The focus of the current review is to evaluate the latest research progress regarding the roles of FOXO proteins in cancer EMT. First, a brief overview of the EMT process in cancer and a general background on the FOXO family are provided. Next, we present the interactions between FOXO proteins and multiple EMT-associated pathways during malignancy development. Finally, we propose several novel potential directions for future research. Collectively, the information compiled herein should serve as a comprehensive repository of information on this topic and should aid in the design of additional studies and the future development of FOXO proteins as therapeutic targets.


Asunto(s)
Factores de Transcripción Forkhead/genética , Familia de Multigenes/genética , Neoplasias/genética , Transición Epitelial-Mesenquimal/genética , Humanos , Terapia Molecular Dirigida , Neoplasias/patología
11.
J Proteome Res ; 18(3): 1088-1098, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30608709

RESUMEN

Salamanders completely regenerate their limbs after amputation. Thus, these animals are unique models to investigate the mechanisms modulating regeneration in vertebrates. To investigate the influence of microRNAs (miRNAs) on newt limb regeneration, the miRNAs and mRNAs were simultaneously profiled using Illumina HiSeq 2500 System during limb regeneration of Cynops orientalis at 3, 7, 14, 30 and 42 days postamputation. A total of 203 miRNAs and 4230 mRNAs were identified to be differentially expressed. Together with the proteomic data obtained from our previous study, integrative analysis of multiple profiling data sets was performed to construct an interaction network of differentially expressed miRNAs, mRNAs and proteins. Results of GO and KEGG analyses showed that the differentially expressed miRNA targets were mainly directed to cytoskeletal remodeling and carbohydrate metabolism. The stage-specific regulation of miRNAs on their targets was analyzed by hierarchical clustering analysis and validated by qRT-PCR. The negative regulation of miR-223 and miR-133a on their targets was tested by performing dual luciferase reporter assay. The integration analysis will provide a powerful tool to identify the regulatory mechanisms of miRNAs and their targets. The results may have implications in understanding the complex mechanisms underlying newt limb regeneration.


Asunto(s)
MicroARNs/genética , Proteoma/genética , Transcriptoma/genética , Urodelos/crecimiento & desarrollo , Animales , Extremidades/crecimiento & desarrollo , Regulación del Desarrollo de la Expresión Génica/genética , Regeneración/genética , Urodelos/genética
12.
J Cell Physiol ; 234(6): 8647-8658, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30515801

RESUMEN

Forkhead box O4 (FOXO4), a member of FOXO family, has been highlighted as an essential transcriptional regulator in many diverse carcinomas. Accumulated studies have demonstrated that FOXO4 is downregulated and associated with tumorigenesis, invasiveness, and metastasis of most human cancer. FOXO4 alteration is also closely linked to the prognosis of various types of cancer. The aim of this review is to comprehensively present the clinical and pathological significance of FOXO4 in human cancer. Additionally, the potential clinical applications of future FOXO4 research are discussed. Collectively, the information reviewed here should increase the potential of FOXO4 as a therapeutic target for cancer.


Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Factores de Transcripción Forkhead/metabolismo , Neoplasias/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Animales , Proteínas de Ciclo Celular/genética , Factores de Transcripción Forkhead/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias/genética , Neoplasias/patología , Pronóstico , Transducción de Señal , Proteínas Supresoras de Tumor/genética
14.
Mol Cancer ; 17(1): 20, 2018 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-29386018

RESUMEN

Growth arrest-specific 6, also known as Gas6, is a human gene encoding the Gas6 protein, which was originally found to be upregulated in growth-arrested fibroblasts. Gas6 is a member of the vitamin K-dependent family of proteins expressed in many human tissues and regulates several biological processes in cells, including proliferation, survival and migration, by binding to its receptors Tyro3, Axl and Mer (TAM). In recent years, the roles of Gas6/TAM signalling in cancer cells and the tumour microenvironment have been studied, and some progress has made in targeted therapy, providing new potential directions for future investigations of cancer treatment. In this review, we introduce the Gas6 and TAM receptors and describe their involvement in different cancers and discuss the roles of Gas6 in cancer cells, the tumour microenvironment and metastasis. Finally, we introduce recent studies on Gas6/TAM targeting in cancer therapy, which will assist in the experimental design of future analyses and increase the potential use of Gas6 as a therapeutic target for cancer.


Asunto(s)
Biomarcadores de Tumor , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Terapia Molecular Dirigida , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Microambiente Tumoral , Animales , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular/genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Metástasis de la Neoplasia , Estadificación de Neoplasias , Neoplasias/genética , Neoplasias/patología , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/metabolismo , Investigación , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/genética , Tirosina Quinasa c-Mer/antagonistas & inhibidores , Tirosina Quinasa c-Mer/metabolismo , Tirosina Quinasa del Receptor Axl
15.
Curr Issues Mol Biol ; 29: 37-48, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29708098

RESUMEN

Macrophages are a specific mononuclear cell group abundant in almost every organ of higher animals. This group is a pivotal part of the immune system and is involved in immune responses against exogenous antigen invasion. Recently, accumulating evidence has demonstrated that macrophages participate in wound repair and tissue regeneration. In this review, we will first introduce the influences of regeneration after injury in various tissues and organs among macrophage-depleted animal models. Second, the possible relationship between macrophages and reparation capacities will be discussed. Finally, we provide a general idea about the roles of macrophages in the injury- regeneration process and then discuss the current challenges and prospects of their clinical application. The information compiled here may be useful for regenerative research and may promote macrophages as a therapeutic target in regenerative medicine.


Asunto(s)
Regeneración Tisular Dirigida , Macrófagos/inmunología , Macrófagos/metabolismo , Animales , Humanos , Macrófagos/citología , Regeneración , Medicina Regenerativa , Cicatrización de Heridas
16.
Biochem Biophys Res Commun ; 505(4): 1189-1194, 2018 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-30322617

RESUMEN

DEAD (Asp-Glu-Ala-Asp) cassette helicase 21 (DDX21) is an ATP-dependent RNA helicase that is overexpressed in various malignancies. There is increasing evidence that DDX21 is involved in carcinogenesis and cancer progression by promoting cell proliferation. However, the functional role of DDX21 in gastric cancer is largely unknown. In this study, we observed that DDX21 was significantly up-regulated in gastric cancer tissues compared to paired adjacent normal tissues. The expression of DDX21 was closely related to the pathological stage of gastric cancer. In vitro and in vivo studies had shown that knockdown of DDX21 inhibited gastric cancer cell proliferation, colony formation, G1/S cell cycle transition and xenograft growth, while ectopic expression of DDX21 promoted these cell functions. Mechanically, DDX21 induced gastric cancer cell growth by up-regulating levels of Cyclin D1 and CDK2. Taken together, these results revealed a novel role for DDX21 in the proliferation of gastric cancer cells via the Cyclin D1 and CDK2 pathways. Therefore, DDX21 can be used as a therapeutic target for gastric cancer.


Asunto(s)
Ciclo Celular , ARN Helicasas DEAD-box/fisiología , Neoplasias Gástricas/metabolismo , Animales , Carcinogénesis , Línea Celular Tumoral , Proliferación Celular , Ciclina D1/genética , Ciclina D1/metabolismo , Quinasa 2 Dependiente de la Ciclina/genética , Quinasa 2 Dependiente de la Ciclina/metabolismo , ARN Helicasas DEAD-box/genética , ARN Helicasas DEAD-box/metabolismo , Femenino , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología
17.
BMC Biotechnol ; 18(1): 12, 2018 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-29514614

RESUMEN

BACKGROUND: Safe and effective hemostatic materials are important for reducing mortality resulting from excessive hemorrhage. In this work, new biomaterials with hemostatic effects were created by fusing the gene coding for RADA-16, a self-assembling peptide with the sequence RADARADARADARADA, to the 3'-end of the open reading frame (ORF) encoding elastin-like polypeptides through gene recombination. RESULTS: The fusion proteins, termed 36R, 60R and 96R, were solubly over-expressed in Escherichia coli BL21 (DE3) based on genetic manipulation of the high-efficiency prokaryotic expression vector pET28a (+) and bacterial transformation. Western Blot analysis showed that the over-expressed proteins were the target fusion proteins. The target proteins 36R with 94.72% purity, 60R with 96.91% purity and 96R with 96.37% purity were prepared using an inverse phase transition cycle at 65 °C followed by His-tag affinity chromatography. The proliferation results of the mouse fibroblast cell line L929 and hippocampus neuron cell line HT22 indicated that the fusion proteins did not cause obvious cell toxicity. The lyophilized spongy film of the purified 36R, 60R and 96R could stop the hemorrhage of a 2 × 2 mm bleeding wound in the mouse liver after 27.21 ± 1.92 s, 18.65 ± 1.97 s and 15.85 ± 1.21 s, respectively. The hemostasis time was 21.23 ± 1.84 s for rat-tail collagen and 14.44 ± 1.33 s for RADA-16 lyophilized on gauze. The hemostatic time of three treated groups were all significantly superior to that of the negative control without any hemostasis treatment, which spontaneously stopped bleeding after 37.64 ± 1.34 s. Statistical analysis showed that the spongy film with purified 96R exhibited an exciting hemostatic effect that was superior to rat-tail collagen and close to that of RADA-16 lyophilized on gauze. CONCLUSIONS: These results revealed that the fusion proteins achieved by gene recombination technology could serve as a promising hemostatic material.


Asunto(s)
Hemostáticos/farmacología , Péptidos/genética , Péptidos/farmacología , Proteínas Recombinantes de Fusión/aislamiento & purificación , Células Cultivadas , Cromatografía de Afinidad , Evaluación Preclínica de Medicamentos/métodos , Elastina/química , Escherichia coli/genética , Vectores Genéticos , Hemostáticos/química , Humanos , Concentración 50 Inhibidora , Hígado/lesiones , Ensayo de Materiales , Microorganismos Modificados Genéticamente , Neuronas/efectos de los fármacos , Péptidos/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Pruebas de Toxicidad
18.
J Org Chem ; 83(23): 14713-14722, 2018 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-30301354

RESUMEN

A copper-catalyzed aerobic oxidative C-C single bond cleavage of acyclic unstrained oxime acetates is reported, providing various aryl nitriles and ketones in good yields. Mechanistic studies indicate a radical procedure is involved in this transformation, and the oxygen atom in the ketone products is originated from O2 in the air. Oxime acetates as an internal oxidant have been proved to be an initiator, which may promote the discovery of novel protocol for C-C bond cleavage and dioxygen activation.

19.
Org Biomol Chem ; 16(10): 1646-1650, 2018 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-29465727

RESUMEN

An AgSCF3 mediated nucleophilic trifluoromethylthiolation reaction for C(sp)-SCF3 bond formation is reported. This nucleophilic trifluoromethylthiolation reaction of bromoalkynones afforded various useful ynonyl trifluoromethyl sulfides in high yields. Interestingly, the over-addition of AgSCF3 is avoided in our approach.

20.
World J Microbiol Biotechnol ; 34(4): 53, 2018 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-29558004

RESUMEN

Pseudomonas aeruginosa DN1 strain and Bacillus subtilis QHQ110 strain were chosen as rhamnolipid and lipopeptide producer respectively, to evaluate the efficiency of exogenous inoculants on enhancing oil recovery (EOR) and to explore the relationship between injected bacteria and indigenous bacterial community dynamics in long-term filed pilot of Hujianshan low permeability water-flooded reservoir for 26 months. Core-flooding tests showed that the oil displacement efficiency increased by 18.46% with addition of exogenous consortia. Bacterial community dynamics using quantitative PCR and high-throughput sequencing revealed that the exogenous inoculants survived and could live together with indigenous bacterial populations. They gradually became the dominant community after the initial activation, while their comparative advantage weakened continually after 3 months of the first injection. The bacterial populations did not exert an observable change in the process of the second injection of exogenous inoculants. On account of facilitating oil emulsification and accelerating bacterial growth with oil as the carbon source by the injection of exogenous consortia, γ-proteobacteria was finally the prominent bacterial community at class level varying from 25.55 to 32.67%, and the dominant bacterial populations were increased by 2-3 orders of magnitude during the whole processes. The content of organic acids and rhamnolipids in reservoir were promoted with the change of bacterial community diversity, respectively. Cumulative oil increments reached 26,190 barrels for 13 months after the first injection, and 55,947 barrels of oil had been accumulated in all of A20 wells block through two rounds of bacterial consortia injection. The performance of EOR has a cumulative improvement by the injection of exogenous inoculants without observable inhibitory effect on the indigenous bacterial populations, demonstrating the application potential in low permeability water-flooded reservoirs.


Asunto(s)
Bacterias/metabolismo , Consorcios Microbianos/fisiología , Aceites/metabolismo , Permeabilidad , Petróleo/microbiología , Bacillus subtilis/metabolismo , Biodiversidad , China , ADN Bacteriano , Glucolípidos/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Microbiología Industrial , Lipopéptidos/metabolismo , Filogenia , Pilotos , Pseudomonas aeruginosa/metabolismo , Tensión Superficial , Tensoactivos
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