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1.
Clin Infect Dis ; 76(3): e1140-e1149, 2023 02 08.
Artículo en Inglés | MEDLINE | ID: mdl-36037029

RESUMEN

BACKGROUND: To provide useful insights into measles elimination progress in China, measles surveillance data were reviewed, and the transmission patterns of measles viruses circulating in China during 1993-2021 were analyzed. METHODS: Measles incidence data from the National Notifiable Disease Reporting System of the China Center for Disease Control and Prevention were analyzed. A total of 17 570 strains were obtained from 30 of 31 provinces in mainland China during 1993-2021. The recommended genotyping window was amplified. Genotyping analysis was conducted for comparison with the reference strains. Phylogenetic analyses were performed to identify genetic relationships among different lineages within the genotypes. RESULTS: With high coverage of routine immunization and intensive supplementary immunization activities, measles incidence has shown a downward trend since 1993, despite 2 resurgences, reaching a historic low level in 2020-2021 (average 0.5 per million). During 1993-2021, 9 genotypes including domestic genotype H1; imported genotypes B3, D4, D8, D9, D11, G3, and H2; and vaccine-associated genotype A were identified. Among them, the genotype H1 strain circulated endemically in China for more than 25 years; the last strain was detected in Yunnan Province in September 2019. Multiple imported genotypes have been identified since 2009 showing different transmission patterns. Since April 2020, no imported strains have been detected, while vaccine-associated genotype A continues to be detected. CONCLUSIONS: The evidence of low incidence during 2020-2021 and virological surveillance data in this study confirm that China is currently approaching measles elimination.


Asunto(s)
Virus del Sarampión , Sarampión , Humanos , Virus del Sarampión/genética , Genotipo , Filogenia , China/epidemiología , Sarampión/epidemiología , Sarampión/prevención & control
2.
J Med Virol ; 95(3): e28611, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36846911

RESUMEN

To better understand the circulation pattern and genetic characterization of human respiratory syncytial virus (HRSV) in China during 2008-2021, a total of 3967 HVR2 sequences were obtained from 20 provinces in China for phylogenetic analysis and sequence variation analysis. The results showed that the HRSV subtype presented the prevalence pattern of "ABBAABAABAAABB." Further genotyping identified seven genotypes for HRSVA and nine genotypes for HRSVB. Multiple genotypes of HRSV were cocirculating during 2008-2015, while ON1 and BA9 became the only predominant genotypes for HRSVA and HRSVB, respectively, since 2015. A genotype switch from NA1 to ON1 for HRSVA occurred in approximately 2014, while genotype BA9 of HRSVB had been the predominant genotype for at least 14 years. ON1 strains could be divided into four lineages with no temporal or geographical distribution tendency. In contrast, BA9 strains could be divided into three lineages with noticeable temporal clustering. Sequence variation analysis showed that two ON1 sequences in 2017 had 10 nucleotide deletion and compensatory extension at the C-terminal; 15 BA9 sequences during 2019-2021 had novel insertions between K225 and E226, along with 6 identical amino acid variant sites. This study further enriched the genetic data of HRSV circulating in China and provided an important basis for the development of HRSV vaccines and drugs as well as the formulation of prevention and control strategies.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Humanos , Lactante , Virus Sincitial Respiratorio Humano/genética , Infecciones por Virus Sincitial Respiratorio/epidemiología , Filogenia , China/epidemiología , Genotipo , Variación Genética
3.
J Labelled Comp Radiopharm ; 66(11): 336-344, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37382087

RESUMEN

Carbon 14 labeled Iclepertin (BI 425809, 1) and its major metabolites were needed for ADME and several other studies necessary for the advancement of this drug candidate in clinical trials. Iclepertin is composed of two main chemical blocks, (R)-5-(methylsulfonyl)-2-([1,1,1-trifluoropropan-2-yl]oxy)benzoic acid (2), and 3-[(1R,5R)-3-azabicyclo[3.1.0]hexan-5-yl]-5-(trifluoromethyl)isoxazole (3) linked to each other via an amide bond. In the first synthesis of carbon 14 labeled 1, 2-fluorobenzoic acid, carboxyl-14 C was converted to [14 C]-2 in three steps and then coupled to 3 to provide [14 C]-1a in 45% overall yield. In the second synthesis, [14 C]-3 was prepared in six radioactive steps and coupled to the acid 2 to furnish [14 C]-1b in 20% overall yield. Both synthetic routes provided [14 C]-1a and [14 C]-1b with specific activities higher than 53 mCi/mmol and radiochemical, chemical, and enantiomeric purities above 98%. Two major metabolites of 1, BI 761036 and BI 758790, were also prepared labeled with carbon 14 using intermediates already available from the synthesis of [14 C]-1.


Asunto(s)
Compuestos Orgánicos , Radioisótopos de Carbono/química , Proteínas de Transporte de Glicina en la Membrana Plasmática/antagonistas & inhibidores , Proteínas de Transporte de Glicina en la Membrana Plasmática/metabolismo , Compuestos Orgánicos/síntesis química , Compuestos Orgánicos/química , Compuestos Orgánicos/metabolismo
4.
J Labelled Comp Radiopharm ; 66(4-6): 145-154, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36931890

RESUMEN

The generation of amyloid beta peptides that aggregate in the brain is believed to play a major role in Alzheimer's disease. In theory, the inhibition of beta-site amyloid precursor protein-cleaving enzyme 1 (BACE1), which catalyzes the initial rate-limiting step in amyloid beta production, may slow or stop Alzheimer's disease. Herein, we report the preparation of two potent BACE1 inhibitors, BI 1147560 (1) and BI 1181181 (2), labeled with carbon-14 and with deuterium. The use of advanced key chiral intermediates like 3 and 5 shortened the carbon-14 syntheses of these two compounds to five and six steps, respectively, and helped in preparing them with very high chemical purity and enantiomeric excess without deviating from the process chemistry route. For the deuterium synthesis, oxetan-3-ylmethanamine [2 H6 ]-7 and 2-fluoro-2-methylpropan-1-amine [2 H6 ]-9 were prepared then used with the chiral intermediate 5 to furnish deuterium labeled 1 and 2, respectively.


Asunto(s)
Enfermedad de Alzheimer , Humanos , Péptidos beta-Amiloides , Secretasas de la Proteína Precursora del Amiloide/fisiología , Precursor de Proteína beta-Amiloide , Ácido Aspártico Endopeptidasas/química , Ácido Aspártico Endopeptidasas/fisiología , Radioisótopos de Carbono , Deuterio , Inhibidores Enzimáticos
5.
J Labelled Comp Radiopharm ; 66(4-6): 155-168, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37057686

RESUMEN

(R)-4-((R)-1-((6-(1-[tert-butyl]-1H-pyrazol-4-yl)-2-methyl-2H-pyrazolo[3,4-d]pyridin-4-yl)oxy)ethyl)pyrrolidin-2-one (BI 894416, 1) and (R)-4-((R)-1-((6-(1-[tert-butyl]-1H-pyrazol-4-yl)-2,3-dimethyl-2H-indazol-4-yl)oxy)ethyl)pyrrolidin-2-one (BI 1342561, 2) are two new potent and selective spleen tyrosine kinase inhibitors developed to treat severe asthma. Both compounds have similar structures and they differ only in the bicyclic moiety 2-methyl-2H-pyrazolo[4,3-c]pyridine in 1 versus 2,3-dimethyl-2H-indazole in 2. In the carbon 14 synthesis, 1-(1-[tert-butyl]-1H-pyrazol-4-yl)ethan-1-one-1-14 C ([14 C]-8) was prepared from the cyanation of 4-bromopyrazole using zinc [14 C]cyanide followed by methyl lithium addition on the nitrile group. The enolate of [14 C]-8 was then used to access these two bicyclic moieties via pyrano-pyrazoles [14 C]-11 and [14 C]-12, which were further transformed in few more steps to [14 C]-(1) and [14 C]-2. Both inhibitors contain a tert-butyl group. Introducing tert-butyl-d9 will not only provide internal standards for bioanalytical studies, but it is also expected to slow down the metabolism of these two compounds. Most of the metabolites of compound 1, for example, are the result of tert-butyl oxidation, like alcohol 3, acid 4, and the further N-demethylation of 4 to 5. The detailed preparation of these deuterium-labeled metabolites is also described.


Asunto(s)
Bazo , Radioisótopos de Carbono/química , Deuterio
6.
J Med Virol ; 94(2): 521-530, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34761827

RESUMEN

Measles is one of the most infectious diseases of humans. It is caused by the measles virus (MeV) and can lead to serious illness, lifelong complications, and even death. Whole-genome sequencing (WGS) is now available to study molecular epidemiology and identify MeV transmission pathways. In the present study, WGS of 23 MeV strains of genotype H1, collected in Mainland China between 2006 and 2018, were generated and compared to 31 WGSs from the public domain to analyze genomic characteristics, evolutionary rates and date of emergence of H1 genotype. The noncoding region between M and F protein genes (M/F NCR) was the most variable region throughout the genome. Although the nucleotide substitution rate of H1 WGS was around 0.75 × 10-3 substitution per site per year, the M/F NCR had an evolutionary rate three times higher, with 2.44 × 10-3 substitution per site per year. Phylogenetic analysis identified three distinct genetic groups. The Time of the Most Recent Common Ancestor (TMRCA) of H1 genotype was estimated at approximately 1988, while the first genetic group appeared around 1995 followed by two other genetic groups in 1999-2002. Bayesian skyline plot showed that the genetic diversity of the H1 genotype remained stable even though the number of MeV cases decreased 50 times between 2014 (52 628) and 2020 (993). The current coronavirus disease 2019 (COVID-19) pandemic might have some effect on the measles epidemic and further studies will be necessary to assess the genetic diversity of the H1 genotype in a post-COVID area.


Asunto(s)
Evolución Molecular , Genoma Viral/genética , Virus del Sarampión/genética , China/epidemiología , Genes Virales/genética , Variación Genética , Genómica , Genotipo , Humanos , Sarampión/epidemiología , Sarampión/virología , Virus del Sarampión/clasificación , Filogenia , ARN Viral/genética
7.
Invest New Drugs ; 40(5): 1125-1132, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35793038

RESUMEN

BACKGROUND: Conversion therapy has been widely applied in various cancer types including intrahepatic cholangiocarcinoma (ICC). The aim of this retrospective study was to evaluate the efficacy and safety of transarterial chemoembolization combined with lenvatinib (TACE-L) as a novel conversion therapy in patients with initially unresectable ICC. METHODS: Enrolled in this retrospective study were patients with unresectable ICC who received TACE-L between January 2015 and May 2018. The patients were evaluated every 2 months for possible secondary resection. RESULTS: Of the 44 eligible patients, 28 (63.6%) were successfully downstaged to receive surgical resection and the other 16 patients were included into the unsuccessfully downstaged group. The overall adverse events during TACE-L were moderate, including 12 patients (27.3%) with Grade 3 or 4 toxicities. Of the 28 downregulated patients, 23 (82.1%) achieved an R0 resection, and 6 (21.4%) had Clavien-Dindo grade ≥ 3 complications, including one postoperative death. Kaplan-Meier curves showed that the successfully downstaged patients had better overall survival (OS) than the unsuccessfully downstaged patients (P = 0.006). Multivariable analysis identified successful TACE-L conversion therapy as a significantly favorable prognostic factor for OS. CONCLUSIONS: TACE-L proves to be a safe and efficacious conversion therapy modality that allows for secondary resectability in patients with initially unresectable ICC.


Asunto(s)
Neoplasias de los Conductos Biliares , Carcinoma Hepatocelular , Quimioembolización Terapéutica , Colangiocarcinoma , Neoplasias Hepáticas , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos/patología , Quimioembolización Terapéutica/efectos adversos , Colangiocarcinoma/tratamiento farmacológico , Colangiocarcinoma/cirugía , Humanos , Neoplasias Hepáticas/patología , Compuestos de Fenilurea , Quinolinas , Estudios Retrospectivos , Resultado del Tratamiento
8.
Cancer Cell Int ; 22(1): 312, 2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36224624

RESUMEN

BACKGROUND: Midazolam (MDZ) is an anaesthetic that is widely used for anxiolysis and sedation. More recently, MDZ has also been described to be related to the outcome of various types of carcinomas. However, how MDZ influences the progression of hepatocellular carcinoma (HCC) and its effects on the biological function and tumour immune microenvironment of this type of tumour remain unknown. METHODS: The effects of MDZ on the proliferation, invasion, and migration of HCC cell lines were examined in vitro using the Cell Counting Kit 8 (CCK8), 5-ethynyl-2'-deoxyuridine (EdU), Transwell, and wound healing assays. Additionally, western blotting was employed to confirm that PD-L1 was expressed. Chromatin immunoprecipitation-seq (ChIP-seq) analysis was used to pinpoint the transcriptional regulation regions of NF-κB and programmed death-ligand 1 (PD-L1). A C57BL/6 mouse model was used to produce subcutaneous HCC tumors in order to evaluate the in vivo performance of MDZ. Mass spectrometry was also used to assess changes in the tumour immunological microenvironment following MDZ injection. RESULTS: The HCC-LM3 and Hep-3B cell lines' proliferation, invasion, and migration were controlled by MDZ, according to the results of the CCK8, EdU, Transwell, and wound healing assays. PD-L1 expression was shown by ChIP-seq analysis to be boosted by NF-κB, and by Western blotting analysis, it was shown that MDZ downregulated the expression of NF-κB. Additionally, in vivo tests revealed that intraperitoneal MDZ injections reduced HCC tumor development and enhanced the effectiveness of anti-PD-1 therapy. The CD45+ immune cell proportions were higher in the MDZ group than in the PBS group, according to the mass spectrometry results. Injection of MDZ resulted in a decrease in the proportions of CD4+ T cells, CD8+ T cells, natural killer (NK) cells, monocytes, Tregs, and M2 macrophages and a rise in the proportion of dendritic cells. Additionally, the concentrations of the cytokines IFN-g and TNF-a were noticeably raised whereas the concentrations of the CD8+ T-cell fatigue markers ICOS, TIGIT, and TIM3 were noticeably lowered. CONCLUSION: According to this study, MDZ inhibited the progression of HCC by inhibiting the NF-κB pathway and reducing the exhaustion of CD8+ T cells. In clinical practice, MDZ combined with anti-PD-1 therapy might contribute to synergistically improving the antitumor efficacy of HCC treatment.

9.
BMC Cancer ; 22(1): 1284, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36476239

RESUMEN

BACKGROUND: Circular RNAs (circRNAs) are enriched in exosomes and are extremely stable. Exosome-mediated intercellular transfer of specific biologically active circRNA molecules can drive the transformation of the tumor microenvironment and accelerate or inhibit the local spread and multifocal growth of hepatocellular carcinoma (HCC). In this study, we explored in depth about the biological roles of HCC cell-derived exosomes and exosome-transported circRNAs on HCC in vivo and in vitro. METHODS: Exosomes extracted from HCC cells (Huh7 and HA22T) were characterized using transmission electron microscopy, nanoparticle size tracer analysis, and western blotting. Exosomes were observed for endocytosis using fluorescent labeling. The effects of HCC cell-derived exosomes and the circ_002136 they carried on cell growth, metastasis and apoptosis were determined by CCK-8 assay, transwell assay, flow cytometry analysis and TUNEL staining, respectively. The expressions of circ_002136, miR-19a-3p and RAB1A were detected by quantitative RT-PCR (qRT-PCR). Targeted binding between miR-19a-3p and circ_002136 or RAB1A was predicted and verified by bioinformatics analysis, dual-luciferase reporter and RNA pull-down experiments. The in vivo effect of circ_002136 was determined by constructing a xenograft tumor model. RESULTS: The findings revealed that Huh7 and HA22T exosomes conferred enhanced viability as well as invasive ability to recipient HCC cells. Circ_002136 was shown for the first time to be differentially upregulated in HCC tissues and cells and transferred by HCC cell-derived exosomes. More importantly, selective silencing of circ_002136 depleted the malignant biological behaviors of HCC exosome-activated Huh7 and HA22T cells. Depletion of circ_002136 in vivo effectively retarded the growth of HCC xenograft tumors. Furthermore, a well-established circ_002136 ceRNA regulatory network was constructed, namely circ_002136 blocked miR-19a-3p expression, elevated RAB1A expression activity and stimulated HCC development. Finally, high levels of circ_002136 or RAB1A, as well as low levels of miR-19a-3p, negatively affected HCC patient survival. CONCLUSION: The study on circ_002136 provides good data to support our insight into the mechanism of to-be-silenced circRNA as a therapeutic agent in the progression of HCC.


Asunto(s)
Carcinoma Hepatocelular , Exosomas , Neoplasias Hepáticas , MicroARNs , Humanos , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Exosomas/genética , ARN Circular/genética , MicroARNs/genética , Microambiente Tumoral
10.
J Am Chem Soc ; 143(10): 3881-3888, 2021 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-33683868

RESUMEN

Selective carbon-carbon (C-C) bond formation in chemical synthesis generally requires prefunctionalized building blocks. However, the requisite prefunctionalization steps undermine the overall efficiency of synthetic sequences that rely on such reactions, which is particularly problematic in large-scale applications, such as in the commercial production of pharmaceuticals. Herein, we describe a selective and catalytic method for synthesizing 1,3-enynes without prefunctionalized building blocks. In this transformation several classes of unactivated internal acceptor alkynes can be coupled with terminal donor alkynes to deliver 1,3-enynes in a highly regio- and stereoselective manner. The scope of compatible acceptor alkynes includes propargyl alcohols, (homo)propargyl amine derivatives, and (homo)propargyl carboxamides. This method is facilitated by a tailored P,N-ligand that enables regioselective addition and suppresses secondary E/Z-isomerization of the product. The reaction is scalable and can operate effectively with as low as 0.5 mol % catalyst loading. The products are versatile intermediates that can participate in various downstream transformations. We also present preliminary mechanistic experiments that are consistent with a redox-neutral Pd(II) catalytic cycle.


Asunto(s)
Alquinos/química , Alquinos/síntesis química , Carbono/química , Catálisis , Oxidación-Reducción , Paladio/química , Propanoles/química , Estereoisomerismo
11.
Emerg Infect Dis ; 27(1): 275-277, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33350918

RESUMEN

We detected human metapneumovirus (HMPV) in 72 (7.1%) of 1,021 patients hospitalized with severe acute respiratory infection in Luohe, China, during 2017-2019. We detected HMPV most frequently in young children and less often in adults. HMPV genotype A2c variants 111 nt and 180 nt duplications predominated, demonstrating their continuing geographic spread.


Asunto(s)
Metapneumovirus , Infecciones por Paramyxoviridae , Infecciones del Sistema Respiratorio , Niño , Preescolar , China/epidemiología , Duplicación de Gen , Humanos , Lactante , Metapneumovirus/genética , Infecciones por Paramyxoviridae/epidemiología , Infecciones del Sistema Respiratorio/epidemiología
12.
J Clin Microbiol ; 58(11)2020 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-32878947

RESUMEN

Along with the implementation of measles case-based surveillance, measles vaccine-associated rash illness (VARI) cases were detected in China. To better understand the characteristics of VARI, 101 VARI cases confirmed by measles virus genotyping in 2011 to 2018 were analyzed in this study. With the decrease in measles incidence, the detection rate of VARI cases increased among the cases confirmed by genotyping. Compared with genotype H1 wild-type measles, VARI occurred throughout the year, without obvious seasonal distribution. Infants and children of ages 8 to 23 months were the main population of VARI. VARI mainly occurred within 14 days after measles vaccination. The number of VARI cases peaked on the 8th day after measles vaccination, which was later than that of genotype H1 wild-type measles cases with a measles vaccination history. VARI presents clinical symptoms similar to those of measles. The frequencies of the "3Cs" (cough, coryza, and conjunctivitis), Koplik spots, and complications in VARI cases were significantly lower than those in wild-type measles cases. In total, 94.06% of sequences from VARI cases were identical to measles vaccine strain S191 in the C-terminal 450-nucleotide sequence of the nucleoprotein (N-450) gene. A few substitutions were found in N-450 sequences of the VARI cases. The confirmation of VARI has become an emerging issue in the process of measles elimination. Rapid confirmation of VARI is critical for measles surveillance and will help to determine the response measures for measles, especially in measles preelimination and elimination settings. The suspected measles cases with measles-containing vaccine (MCV) vaccination were recommended to be tested by the laboratory to identify wild-type measles or VARI.


Asunto(s)
Exantema , Sarampión , China/epidemiología , Brotes de Enfermedades , Exantema/epidemiología , Humanos , Lactante , Sarampión/epidemiología , Sarampión/prevención & control , Vacuna Antisarampión/efectos adversos , Virus del Sarampión/genética , Vacunación
13.
Arch Virol ; 165(8): 1895-1898, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32462283

RESUMEN

We previously reported genotype D11 strains of measles virus that were first isolated from a measles outbreak associated with imported cases in Yunnan province of China by Zhang et al. (Emerg Infect Dis 16(6):943-7, 2010). Genotype D11 has been identified as the 24th genotype of the WHO reference strains. In this study, we sequenced the whole genome of a D11 strain. Phylogenetic analysis using the complete genome sequences of D11 and other reference strains showed that the D11 strain formed a distinct branch that was distant from the other genotypes and was most closely related to the reference strain D7. The M-F non-coding region (NCR) and the N450 coding region sequence (CDS) were found to be the most variable regions. This report provides basic genetic data on genotype D11 for further study of measles evolution and the support for measles elimination.


Asunto(s)
Genoma Viral/genética , Virus del Sarampión/genética , China , Brotes de Enfermedades , Genotipo , Humanos , Sarampión/virología , Filogenia , Análisis de Secuencia de ADN/métodos
14.
Microvasc Res ; 123: 81-85, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30576698

RESUMEN

OBJECTIVE: To evaluate perfusion alterations in skeletal muscle in a canine hind limb ischemia model using color-coded digital subtraction angiography (CC-DSA). METHODS: Twelve beagles underwent embolization at the branch of their left deep femoral artery. Right hind limbs were used as the control group. Angiography was performed before and immediately after embolization. Upon CC-DSA analysis, time to peak (TTP) was measured before embolization in both sides of the beagles' hind limbs at the middle iliac artery, and the distant, middle and proximal femoral artery. Regions of interest (ROI) peak and ROI peak time were symmetrically computed in proximal and distal thigh muscles before and immediately after embolization. The data were analyzed and compared using the Wilcoxon signed rank test. RESULTS: Before embolization, ROI peak in the proximal thigh was lower than in the ipsilateral distal thigh, whereas ROI peak time in the proximal thigh was longer than in the distal thigh. In the iliac femoral artery, there was no significant difference in ROI peak, ROI peak time, or TTP between right and left sides. After embolization, ROI peaks in proximal and distal skeletal muscles of the left hind limb were significantly lower than on the contralateral side. ROI peak time was significantly longer in the left proximal and left distal thigh compared to the contralateral side. There were no significant changes in ROI peak or ROI peak time in the right proximal and right distal thigh compared to pre-embolization values. Changes in ROI peak and ROI peak time were larger in the left proximal than in the left distal thigh. CONCLUSION: CC-DSA provided real-time measurement of changes in vascular hemodynamics and skeletal muscle perfusion without increasing X-ray usage or contrast agent dose.


Asunto(s)
Angiografía de Substracción Digital/métodos , Hemodinámica , Isquemia/diagnóstico por imagen , Músculo Esquelético/irrigación sanguínea , Imagen de Perfusión/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Animales , Velocidad del Flujo Sanguíneo , Modelos Animales de Enfermedad , Perros , Femenino , Miembro Posterior , Isquemia/inducido químicamente , Isquemia/fisiopatología , Masculino , Alcohol Polivinílico , Valor Predictivo de las Pruebas , Flujo Sanguíneo Regional , Factores de Tiempo
15.
Anal Biochem ; 586: 113413, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31479631

RESUMEN

The Hippo signaling pathway controls cell-cell contact, cell proliferation, as well as organ size by integrating changes in the cellular microenvironment. In recent years, the pivotal role of Hippo signaling in cancers has been well recognized. Inhibition of the pathway promotes the translocation of the major Hippo pathway effectors, the yes-associated protein (YAP) and its paralog TAZ, to the nucleus, where they interact with the transcription factor family transcriptional enhancer associate domain (TEAD), thus coactivating the expression of downstream genes, leading to cell transformation, tissue overgrowth, and tumor development. Therefore, the interruption of the YAP-TEAD transcriptional complex represents a novel opportunity for the treatment of cancer. Here, we established a fluorescence polarization (FP)-based assay for the identification and evaluation of YAP-TEAD protein-protein interface (PPI) inhibitors at the YAP Ω-loop binding region of TEAD, which is also called interface 3 at the YAP-TEAD binding surface. Furthermore, a patented small molecule (Patent-22) was evaluated by the FP assay, which confirmed that it was a YAP-TEAD PPI inhibitor at interface 3. Possessing great application value, this FP method is reliable, robust, and economical for inhibitor assessment and drug discovery.


Asunto(s)
Proteínas de Ciclo Celular/antagonistas & inhibidores , Péptidos , Bibliotecas de Moléculas Pequeñas , Factores de Transcripción/antagonistas & inhibidores , Cristalografía por Rayos X , Polarización de Fluorescencia , Humanos , Modelos Moleculares , Estructura Molecular , Péptidos/análisis , Péptidos/farmacología , Unión Proteica/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/análisis , Bibliotecas de Moléculas Pequeñas/farmacología
16.
J Org Chem ; 84(8): 4926-4931, 2019 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-30715884

RESUMEN

The application of a Buchwald's third generation palladacycle containing a dihydrobenzooxaphosphole-based ligand (e.g., BIDIME) was reported in the Suzuki cross-coupling reaction. Using flow technology, high yield and reproducible Suzuki cross-coupling reaction for one of our key intermediates was achieved with Pd loadings as low as 0.5 mol %. This continuous flow approach overcomes catalyst deactivation and scale dependence issues that can be a problem in some traditional batch-mode operations and responds to the challenge of improving process greenness.

17.
J Mater Sci Mater Med ; 30(4): 47, 2019 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-30980130

RESUMEN

The objective of this study was to fabricate and characterize chitosan combined with different amounts of simvastatin-loaded nanoparticles and to investigate their potential for guided bone regeneration in vitro and in vivo. Different SIM-CSN formulations were combined into a chitosan scaffold (SIM-CSNs-S), and the morphology, simvastatin release profile, and effect on cell proliferation and differentiation were investigated. For in vivo experiments, ectopic osteogenesis and the critical-size cranial defect model in SD rats were chosen to evaluate bone regeneration potential. All three SIM-CSNs-S formulations had a porous structure and exhibited sustained simvastatin release. CSNs-S showed excellent degradation and biocompatibility characteristics. The 4 mg SIM-CSNs-S formulation stimulated higher BMSC ALP activity levels, demonstrated significantly earlier collagen enhancement, and led to faster bone regeneration than the other formulations. SIM-CSNs-S should have a significant effect on bone regeneration.


Asunto(s)
Regeneración Ósea/efectos de los fármacos , Quitosano/química , Regeneración Tisular Dirigida/métodos , Nanopartículas/química , Nanopartículas/metabolismo , Simvastatina/farmacocinética , Andamios del Tejido/química , Animales , Huesos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/metabolismo , Preparaciones de Acción Retardada , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Composición de Medicamentos , Masculino , Ensayo de Materiales , Microesferas , Osteogénesis/efectos de los fármacos , Osteogénesis/fisiología , Ratas , Ratas Sprague-Dawley , Simvastatina/administración & dosificación , Propiedades de Superficie , Ingeniería de Tejidos/métodos
19.
J Org Chem ; 83(3): 1448-1461, 2018 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-29323903

RESUMEN

A chromatography-free, asymmetric synthesis of the C2-symmetric P-chiral diphosphine t-Bu-SMS-Phos was developed using a chiral auxiliary-based approach in five steps from the chiral auxiliary in 36% overall yield. Separtion and recovery of the auxiliary were achieved with good yield (97%) to enable recycling of the chiral auxiliary. An air-stable crystalline form of the final ligand was identified to enable isolation of the final ligand by crystallization to avoid chromatography. This synthetic route was applied to prepare up to 4 kg of the final ligand. The utility of this material was demonstrated in the asymmetric hydrogenation of trifluoromethyl vinyl acetate at 0.1 mol % Rh loading to access a surrogate for the pharmaceutically relavent chiral trifluoroisopropanol fragment in excellent yield and enantiomeric excess (98.6%).

20.
J Mater Sci Mater Med ; 29(6): 84, 2018 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-29892913

RESUMEN

This study aimed to develop of a rapid and effective method to occlude dentinal tubules using carboxymethyl chitosan and lysozyme (CMC/LYZ) nanogels with encapsulated amorphous calcium phosphate (ACP) based on the transformation of ACP to HAP. In this work, CMC/LYZ was used to stabilize ACP and form CMC/LYZ-ACP nanogels, and then the nanogel-encapsulated ACP was applied to exposed dentinal tubule surfaces. The morphology of the nanogels was examined by transmission electron microscopy (TEM). Distribution and quantity of elements in CMC/LYZ-ACP nanogels were determined by element mapping and energy dispersive X-Ray spectroscopy (EDX). Scanning electron microscopy (SEM) images, XRD measurements and nanoindentation were applied to check the efficacy of tubular occlusion. TEM revealed that CMC/LYZ-ACP nanogels were spherical dense gel particles with size approximately 50-500 nm. Element mapping and EDX indicated that C, N, O, Ca, P, and S in the microspheres are thoroughly represented. SEM images shows that the thickness of the coating layer was approximately 1-2 µm and the depth to which the mineralized substance enters the dentinal tubule was approximately 4-8 µm. XRD measurements and nanoindentation indicated that the occluding mineralized substance observed were similar to nature dentin. CMC can form spherical dense nanogels loaded with ACP under the participation of lysozyme. The CMC/LYZ-ACP nanogels could increase the dentinal tubule occluding effectiveness. These results indicated that finding and developing novel nanomaterials of CMC/LYZ-ACP would be an effective strategy for the treatment of dentin hypersensitivity.


Asunto(s)
Fosfatos de Calcio/química , Quitosano/análogos & derivados , Sensibilidad de la Dentina/terapia , Diente Molar/patología , Muramidasa/química , Nanopartículas/química , Adolescente , Adulto , Quitosano/química , Dentina/química , Ácido Edético/química , Módulo de Elasticidad , Geles , Humanos , Luz , Microscopía Electrónica de Rastreo , Microesferas , Tamaño de la Partícula , Permeabilidad , Reproducibilidad de los Resultados , Dispersión de Radiación , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X , Adulto Joven
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