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1.
Chem Asian J ; : e202400195, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38751300

RESUMEN

In this study, we have successfully designed and synthesized two novel dual-emission emitters featuring phenothiazine-5-oxide and phenothiazine-5,5-dioxide motifs, characterized by highly lopsided and asymmetric conformational states. Through rigorous spectral examinations and DFT calculations, the compounds exhibit distinctive ICT phenomena, coupled with efficient emission in solid states and AIEE characteristics under high water fractions in DMF/H2O mixtures. These non-planar luminogens exhibit vibrant green and blue solid-state luminescence, with fluorescence quantum yields of 24.1 % and 15.21 %, respectively. Additionally, they both emit green fluorescence in THF solution, with notable emission quantum yields (QYs) 36.4 % and 30.4 %. Comprehensive theoretical investigations unveil well-defined electron cloud density separation between the energies of HOMO/LUMO levels within the two luminogens. Notably, the targeted molecule harboring the phenothiazine-S,S-dioxide motif also demonstrates remarkable reversible mechanofluorochromic properties. Moreover, we testify their potential in applications such as solid-state rewritable information storage and live-cell imaging in solution states. Through theoretical calculations and comparative studies, we have explored the intrinsic relationship between molecular structure and performance, effectively screening and identifying new fluorescent molecules exhibiting outstanding luminescent attributes. These discoveries establish a robust theoretical and technical foundation for the synthesis and application of efficient DSE-based MFC materials, opening new avenues in the realm of advanced luminescent materials.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 292: 122427, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-36764141

RESUMEN

In this work, two novel luminescent molecules containing distorted phenothiazine-S-oxide and phenothiazine-S,S dioxide skeletons were synthesized by oxidation reactions using different oxidants (m-chloroperoxybenzoic acid, acetic acid /hydrogen peroxide). The target compounds were all confirmed by 1H NMR, 13C NMR and EI-MS. Combined with the results of UV-vis absorption spectra and fluorescence emission spectra, we found that the different oxidation states of S-atom, from sulfide (+2) to sulfoxide (+4) and sulfone (+6), led to the blue, yellow-green and yellowish fluorescence of these compounds in the solid states. Subsequent studies showed that the molecule containing the phenothiazine-S-oxide skeleton exhibited obvious solvatochromism, and the increase of solvent polarity induced a red-shift in the emission wavelength. Moreover, this molecule also exhibited a rare self-recovery mechanochromatic behavior. In addition, these properties were further confirmed by theoretical calculations and X-ray single-crystal diffraction analysis.

3.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 53(5): 911-915, 2022 Sep.
Artículo en Chino | MEDLINE | ID: mdl-36224696

RESUMEN

Objective: To measure the parameters of eye movement of young adult patients of myopia, to compare the differences in the parameters of patient groups with varied degrees of myopia, and to analyze the correlation between eye movement parameters and axial length (AL) and spherical equivalent refraction (SER). Methods: A total of 91 young adult patients of myopia were recruited. The subjects were divided into three groups of low, moderate, and high myopia according to their SER. Information on the subjects' age and sex was collected and general clinical examination was completed. The subjects' binocular fixation, reflexive saccade, and antisaccade were measured with eye tracker. One-way ANOVA or Kruskal-wallis test was used to compare the general data and eye movement parameters of the three groups of myopic patients. Pearson or Spearman correlation analysis was used to analyze AL and SER's correlation with 95% bivariate contour ellipse area (BCEA) and saccadic parameters. Results: The 95% BCEA for mild, moderate, and high myopia groups were 2.08 (0.54, 14.69) deg 2, 4.99 (0.94, 49.22) deg 2, and 5.79 (2.18, 64.91) deg 2, respectively. There was significant difference between the 95% BCEA of the three groups ( P=0.029). The 95% BCEA of the mild myopia group was significantly smaller than that of the high myopia group ( P=0.01). There were no significant differences in saccadic parameters among the three groups ( P>0.05). There was a significant positive correlation between 95% BCEA and AL ( r=0.342, P=0.001). There was a significant negative correlation between 95% BCEA and SER ( r=-0.322, P=0.002). There was no significant correlation between the parameters of saccadic movement and the AL or SER ( P>0.05). Conclusion: For young adult myopic patients, the longer the AL is, the higher the degree of the myopia and the worse the fixation stability becomes. The fixation stability of patients with high myopia was significantly worse than that of patients with mild myopia. There was no significant difference in saccadic parameters in patients with different degrees of myopia.


Asunto(s)
Movimientos Oculares , Miopía , Longitud Axial del Ojo , Humanos , Refracción Ocular , Adulto Joven
4.
Curr Issues Mol Biol ; 44(6): 2614-2621, 2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35735619

RESUMEN

An enhancer trap (ET) mediated by a transposon is an effective method for functional gene research. Here, an ET system based on a PB transposon that carries a mini Krt4 promoter (the keratin4 minimal promoter from zebrafish) and the green fluorescent protein gene (GFP) has been used to produce zebrafish ET lines. One enhancer trap line with eye-specific expression GFP named EYE was used to identify the trapped enhancers and genes. Firstly, GFP showed a temporal and spatial expression pattern with whole-embryo expression at 6, 12, and 24 hpf stages and eye-specific expression from 2 to 7 dpf. Then, the genome insertion sites were detected by splinkerette PCR (spPCR). The Krt4-GFP was inserted into the fourth intron of the gene itgav (integrin, alpha V) in chromosome 9 of the zebrafish genome, with the GFP direction the same as that of the itgav gene. By the alignment of homologous gene sequences in different species, three predicted endogenous enhancers were obtained. The trapped endogenous gene itgav, whose overexpression is related to hepatocellular carcinoma, showed a similar expression pattern as GFP detected by in situ hybridization, which suggested that GFP and itgav were possibly regulated by the same enhancers. In short, the zebrafish enhancer trap lines generated by the PB transposon-mediated enhancer trap technology in this study were valuable resources as visual markers to study the regulators and genes. This work provides an efficient method to identify and isolate tissue-specific enhancer sequences.

5.
Front Med (Lausanne) ; 7: 547, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33015099

RESUMEN

We report the clinical characteristics, viral shedding duration, and contact tracing for asymptomatic carriers of SARS-CoV-2 in Wuhan, China. The asymptomatic carriers were relatively young (median age: 34.5 years). Chest computed tomography showed no abnormalities. The nasopharyngeal swab was an optimum specimen for RNA testing. The median viral shedding duration was 11.5 days. Notably, 2 months of viral shedding duration were reported in two nurses, which was much longer than previously reported or than usually thought. The transmissibility of SARS-CoV-2 by asymptomatic carriers during the studied period in Wuhan appeared to be weak. Only one patient (1/12) was found to have transmitted the virus to another person. Early asymptomatic carrier detection, isolation, and contact tracing could be useful to mitigate the spread of the disease.

6.
Open Forum Infect Dis ; 7(9): ofaa324, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32959016

RESUMEN

Clinical data on coronavirus disease 2019 (COVID-19) with pancreatic injury are extremely limited. An acute manifestation of acute pancreatitis in COVID-19 has not been reported. We describe here 2 cases of COVID-19 with acute pancreatitis as the initial manifestation in Wuhan, China. Patient 1 died despite maximal mechanical ventilatory support and circulation support, while patient 2 was finally discharged after showing significant improvement. Low T cells in peripheral blood may indicate a poor outcome.

7.
Medicine (Baltimore) ; 99(31): e21597, 2020 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-32756215

RESUMEN

INTRODUCTION: Since the coronavirus disease 2019 (COVID-19) outbreak in Wuhan in late 2019, controversy on the use of corticosteroids for COVID-19 has obtained increasing attention. We present 1 critically ill patient who had a rapid therapeutic response to moderate-dose corticosteroids. PATIENT CONCERNS: A 53-year-old critically ill woman from Wuhan suffered with COVID-19. DIAGNOSIS: The chest computed tomography scan was suggestive of COVID-19. The diagnosis was confirmed by a real-time reverse transcription polymerase chain reaction test for SARS-CoV-2. The critically ill status was characterized by worsening dyspnea, progressing bilateral lung consolidation, and poor oxygenation (SiO2/FiO2:110 mm Hg). INTERVENTIONS: The patient was treated with a moderate dose of intravenous corticosteroids and high-flow nasal cannula oxygen therapy. OUTCOMES: After the initiation of corticosteroids, the patient rapidly improved over the following 6 days. Serial chest computed tomography scans showed good absorption of the consolidations. The patient was discharged on Day 17 of hospitalization without obvious adverse effects. CONCLUSIONS: Early use of moderate-dose corticosteroids over a short period may enhance recovery from COVID-19 in critically ill patients.


Asunto(s)
Corticoesteroides/administración & dosificación , Infecciones por Coronavirus/tratamiento farmacológico , Terapia por Inhalación de Oxígeno/métodos , Neumonía Viral/tratamiento farmacológico , Betacoronavirus , COVID-19 , Terapia Combinada , Infecciones por Coronavirus/virología , Femenino , Humanos , Persona de Mediana Edad , Pandemias , Neumonía Viral/virología , SARS-CoV-2 , Resultado del Tratamiento , Tratamiento Farmacológico de COVID-19
8.
Sci Bull (Beijing) ; 65(18): 1516-1518, 2020 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36738065
9.
Chem Commun (Camb) ; 55(44): 6151-6164, 2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31093637

RESUMEN

Chiral tetrahydrocarbazoles (THCs) are prevalent in numerous natural indole alkaloids as well as synthetic pharmaceuticals, and exhibit a broad spectrum of bioactivities. As such, the development of efficient synthetic methodologies for the synthesis of chiral THCs is of substantial interest. The advent of asymmetric catalysis provides a powerful platform to assemble chiral THC motifs and great efforts have been devoted to this field over the past decades. In this feature article, we summarise recent advances in catalytic asymmetric synthesis of THCs, with particular emphases on reaction types and reaction mechanism.


Asunto(s)
Carbazoles/síntesis química , Alquilación , Carbazoles/química , Catálisis , Reacción de Cicloadición , Indoles/química , Ácidos de Lewis/química , Estructura Molecular , Estereoisomerismo
10.
Lancet Respir Med ; 5(9): 707-716, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28734822

RESUMEN

BACKGROUND: For patients with non-small-cell lung cancer (NSCLC) and multiple brain metastases, whole-brain irradiation (WBI) is a standard-of-care treatment, but its effects on neurocognition are complex and concerning. We compared the efficacy of an epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), icotinib, versus WBI with or without chemotherapy in a phase 3 trial of patients with EGFR-mutant NSCLC and multiple brain metastases. METHODS: We did a multicentre, open-label, parallel randomised controlled trial (BRAIN) at 17 hospitals in China. Eligible participants were patients with NSCLC with EGFR mutations, who were naive to treatment with EGFR-TKIs or radiotherapy, and had at least three metastatic brain lesions. We randomly assigned participants (1:1) to either icotinib 125 mg orally (three times per day) or WBI (30 Gy in ten fractions of 3 Gy) plus concurrent or sequential chemotherapy for 4-6 cycles, until unacceptable adverse events or intracranial disease progression occurred. The randomisation was done by the Chinese Thoracic Oncology Group with a web-based allocation system applying the Pocock and Simon minimisation method; groups were stratified by EGFR gene mutation status, treatment line (first line or second line), brain metastases only versus both intracranial and extracranial metastases, and presence or absence of symptoms of intracranial hypertension. Clinicians and patients were not masked to treatment assignment, but individuals involved in the data analysis did not participate in the treatments and were thus masked to allocation. Patients receiving icotinib who had intracranial progression only were switched to WBI plus either icotinib or chemotherapy until further progression; those receiving icotinib who had extracranial progression only were switched to icotinib plus chemotherapy. Patients receiving WBI who progressed were switched to icotinib until further progression. Icotinib could be continued beyond progression if a clinical benefit was observed by the investigators (eg, an improvement in cognition or intracranial pressure). The primary endpoint was intracranial progression-free survival (PFS), defined as the time from randomisation to either intracranial disease progression or death from any cause. We assessed efficacy and safety in the intention-to-treat population (all participants who received at least one dose of study treatment), hypothesising that intracranial PFS would be 40% longer (hazard ratio [HR] 0·60) with icotinib compared with WBI. This trial is registered with ClinicalTrials.gov, number NCT01724801. FINDINGS: Between Dec 10, 2012, and June 30, 2015, we assigned 176 participants to treatment: 85 to icotinib and 91 to WBI. 18 withdrew from the WBI group before treatment, leaving 73 for assessment. Median follow-up was 16·5 months (IQR 11·5-21·5). Median intracranial PFS was 10·0 months (95% CI 5·6-14·4) with icotinib versus 4·8 months (2·4-7·2) with WBI (equating to a 44% risk reduction with icotinib for an event of intracranial disease progression or death; HR 0·56, 95% CI 0·36-0·90; p=0·014). Adverse events of grade 3 or worse were reported in seven (8%) of 85 patients in the icotinib group and 28 (38%) of 73 patients in the WBI group. Raised concentrations of alanine aminotransferase and rash were the most common adverse events of any grade in both groups, occurring in around 20-30% of each group. At the time of final analysis, 42 (49%) patients in the icotinib group and 37 (51%) in the WBI group had died. 78 of these patients died from disease progression, and one patient in the WBI group died from thrombogenesis related to chemotherapy. INTERPRETATION: In patients with EGFR-mutant NSCLC and multiple brain metastases, icotinib was associated with significantly longer intracranial PFS than WBI plus chemotherapy, indicating that icotinib might be a better first-line therapeutic option for this patient population. FUNDING: Guangdong Provincial Key Laboratory of Lung Cancer Translational Medicine, National Health and Family Planning Commission of China, Guangzhou Science and Technology Bureau, Betta Pharmaceuticals, and the Chinese Thoracic Oncology Group.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/radioterapia , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Irradiación Craneana/métodos , Éteres Corona/uso terapéutico , Receptores ErbB/genética , Neoplasias Pulmonares , Quinazolinas/uso terapéutico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/secundario , Supervivencia sin Enfermedad , Receptores ErbB/antagonistas & inhibidores , Femenino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Mutación , Modelos de Riesgos Proporcionales , Resultado del Tratamiento
11.
Bioresour Technol ; 221: 385-393, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27660989

RESUMEN

In this study, five microalgae strains were cultured for their ability to survive in biogas slurry, remove nitrogen resources and accumulate carbohydrates. It was proved that five microalgae strains adapted in biogas slurry well without ammonia inhibition. Among them, Chlorella vulgaris ESP-6 showed the best performance on carbohydrate accumulation, giving the highest carbohydrate content of 61.5% in biogas slurry and the highest ammonia removal efficiency and rate of 96.3% and 91.7mg/L/d respectively in biogas slurry with phosphorus and magnesium added. Additionally, the absence of phosphorus and magnesium that can be adverse for biomass accumulation resulted in earlier timing of carbohydrate accumulation and magnesium was firstly recognized and proved as the influence factor for carbohydrate accumulation. Microalgae that cultured in biogas slurry accumulated more carbohydrate in cell, making biogas slurry more suitable medium for the improvement of carbohydrate content, thus can be regarded as a new strategy to accumulate carbohydrate.


Asunto(s)
Biocombustibles/microbiología , Carbohidratos/química , Chlorella vulgaris , Amoníaco/química , Biomasa , Microalgas , Nitrógeno/química , Fósforo/química
12.
Nat Commun ; 5: 5500, 2014 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-25413598

RESUMEN

Through nearly 50 years of development, sulphur ylides have been established as versatile and powerful reagents for the construction of carbocycles and heterocycles. Despite advances, two important and yet elusive bottlenecks continue to inhibit the advancement of this chemistry: a limited number of reagents with polar groups to react with sulphur ylides, and the wide utilization of chiral auxiliaries or substrates to achieve asymmetric cycloaddition processes in the majority of known reports. Herein, we apply an asymmetric palladium catalysis strategy to the chemistry of sulphur ylides to address these two fundamental problems. We thus achieve an unprecedented decarboxylation-cycloaddition sequence of cyclic allylic esters with sulphur ylides through the enantioselective trapping of Pd-stabilized zwitterionic intermediates by the ylides. As a result, a series of biologically and synthetically important 3-vinyl indolines are rapidly assembled with a high reaction efficiency and stereoselectivity.

13.
Asian Pac J Cancer Prev ; 15(17): 7195-200, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25227813

RESUMEN

BACKGROUND: The aim of this study was to evaluate how CYP2C19 affects icotinib and metabolite' exposure, and to determine whether the exposure and EGFR genotype influences survival time, tumor metastasis and adverse drug reactions. MATERIALS AND METHODS: 274 NSCLC patients who accepted 125 mg icotinib/t.i.d. were chosen from a phase III study. Blood samples were obtained in 672 nd (4th week) and 1,680 th hours (10th week), and plasma was used to quantify the concentration of icotinib and blood cells were sampled to check the genotypes. Clinical data were also collected at the same time, including EGFR genotypes. Plasma concentrations were assessed by HPLC-MS/MS and genotype by sequencing. All data were analyzed through SPSS 17.0 and SAS 9.2. RESULTS: CYP 2C19 genotypes affected bio-transformation from icotinib to M24 and M26, especially in poor-metabolisers. Higher icotinib concentrations (>1000 ng/mL) not only increased patient PFS and OS but also reduced tumor metastasis. Patients with mutant EGFR experienced a higher median PFS and OS (234 and 627 days), especially those with the 19del genotype demonstrating higher PR ratio. Patients who suffered grade II skin toxicity had a higher icotinib exposure than those with grade I skin toxicity or no adverse effects. Liver toxic reactions might occur in patients with greater M20 and M23 plasma concentrations. CONCLUSIONS: CYP2C19 polymorphisms significantly affect icotinib, M24 and M26 exposure. Patients with mutant EGFR genotype and higher icotinib concentration might have increased PFS and OS and lower tumor metastasis. Liver ADR events and serious skin effects might be respectively induced by greater M20, M23 and icotinib concentrations.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Éteres Corona/uso terapéutico , Citocromo P-450 CYP2C19/genética , Genes erbB-1/genética , Neoplasias Pulmonares/tratamiento farmacológico , Quinazolinas/uso terapéutico , Adulto , Anciano , Antineoplásicos/metabolismo , Pueblo Asiatico/genética , Carcinoma de Pulmón de Células no Pequeñas/genética , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Enfermedad Hepática Inducida por Sustancias y Drogas/genética , China , Cromatografía Líquida de Alta Presión , Éteres Corona/metabolismo , Citocromo P-450 CYP2C19/metabolismo , Supervivencia sin Enfermedad , Erupciones por Medicamentos/etiología , Erupciones por Medicamentos/genética , Femenino , Genotipo , Humanos , Neoplasias Pulmonares/genética , Masculino , Persona de Mediana Edad , Pronóstico , Quinazolinas/metabolismo , Espectrometría de Masas en Tándem
14.
Sci Rep ; 4: 4324, 2014 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-24632756

RESUMEN

The present study was to synthesize a novel multi-targeted kinase inhibitor and evaluated its anticancer effects on a hepatocellular carcinoma xenograft model. In our study, in vivo efficacy was determined in nude mice bearing HuH7 human HCC xenografts. The mice were randomly divided into the following five groups with the use of a randomization chart (n = 8 in each group): high-dose BZG-4000 group, medium-dose BZG-4000 group, low-dose BZG-4000 group, sorafenib group, and model group. Tumor size measurements included the length (L) and width (W) measured with calipers, and tumor volume was calculated as (LW∧2)/2. Tumor tissues slides were hematoxylin and eosin (HE) stained for histopathological examination. Immunohistochemistry detected CD31 expression, and Western blotting measured VEGF protein expression. We found that when BZG-4000 was administered orally to xenograft HuH7 nude mice, tumor growth was inhibited and significant tumor shrinkage was evident. After oral administration of BZG-4000 at 40 mg/kg/day, the tumor weight and volume were significantly lower than tumors of the sorafenib group. BZG-4000 considerably decreased the expression of CD31 and VEGF in tumors compared to tumors treated with positive control drug. It was concluded that BZG-4000 has the potential to inhibit the tumorigenesis of hepatocellular carcinoma in vivo by decreasing the expression of CD31 and VEGF.


Asunto(s)
Inhibidores de la Angiogénesis/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Neovascularización Patológica/prevención & control , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Administración Oral , Inhibidores de la Angiogénesis/síntesis química , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Esquema de Medicación , Expresión Génica , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Hepatocitos/patología , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neovascularización Patológica/genética , Neovascularización Patológica/metabolismo , Neovascularización Patológica/patología , Niacinamida/análogos & derivados , Niacinamida/farmacología , Compuestos de Fenilurea/síntesis química , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/genética , Molécula-1 de Adhesión Celular Endotelial de Plaqueta/metabolismo , Inhibidores de Proteínas Quinasas/síntesis química , Sorafenib , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Chemistry ; 20(12): 3415-20, 2014 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-24677230

RESUMEN

An unprecedented Zn(OTf)2-catalyzed asymmetric Michael addition/cyclization cascade of 3-nitro-2H-chromenes with 3-isothiocyanato oxindoles has been disclosed. This transformation provides an efficient access to various synthetically important polycyclic spirooxindoles in a highly stereoselective manner under mild conditions (72­99% yields, up to >95:5 d.r. and >99% ee). The reaction leads to the formation of three consecutive stereocenters, including 1,3-nonadjacent tetrasubstituted carbon stereocenters, in a single operation. A bifunctional activation model of the chiral Zn(OTf)2/bis(oxazoline) complex was proposed based on control experiments, wherein the ZnII moiety serves as a Lewis acid and the N atom of the free NH group acts as a Lewis base by a hydrogen-bonding interaction.


Asunto(s)
Benzopiranos/química , Indoles/síntesis química , Compuestos Policíclicos/síntesis química , Compuestos de Espiro/síntesis química , Catálisis , Ciclización , Indoles/química , Estructura Molecular , Oxindoles , Compuestos Policíclicos/química , Compuestos de Espiro/química , Estereoisomerismo
16.
PLoS One ; 8(9): e73518, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24019925

RESUMEN

von Willebrand factor (VWF) tethers platelets to sites of vascular injury via interaction with the platelet surface receptor, GPIb. To further define the VWF sequences required for VWF-platelet interaction, a phage library displaying random VWF protein fragments was screened against formalin-fixed platelets. After 3 rounds of affinity selection, DNA sequencing of platelet-bound clones identified VWF peptides mapping exclusively to the A1 domain. Aligning these sequences defined a minimal, overlapping segment spanning P1254-A1461, which encompasses the C1272-C1458 cystine loop. Analysis of phage carrying a mutated A1 segment (C1272/1458A) confirmed the requirement of the cystine loop for optimal binding. Four rounds of affinity maturation of a randomly mutagenized A1 phage library identified 10 and 14 unique mutants associated with enhanced platelet binding in the presence and absence of botrocetin, respectively, with 2 mutants (S1370G and I1372V) common to both conditions. These results demonstrate the utility of filamentous phage for studying VWF protein structure-function and identify a minimal, contiguous peptide that bind to formalin-fixed platelets, confirming the importance of the VWF A1 domain with no evidence for another independently platelet-binding segment within VWF. These findings also point to key structural elements within the A1 domain that regulate VWF-platelet adhesion.


Asunto(s)
Bacteriófagos/genética , Plaquetas/metabolismo , Factor de von Willebrand/metabolismo , Secuencia de Bases , Cartilla de ADN , Vectores Genéticos , Mutagénesis , Mapeo Peptídico , Reacción en Cadena de la Polimerasa , Factor de von Willebrand/química , Factor de von Willebrand/genética
17.
Angew Chem Int Ed Engl ; 51(36): 9137-40, 2012 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-22888071

RESUMEN

Batting the ylides: A simple procedure carried out under mild conditions allows the direct and efficient synthesis of structurally diverse indoles. This approach involves a cascade reaction of sulfur ylides and N-(ortho-chloromethyl)aryl amides.


Asunto(s)
Amidas/química , Indoles/química , Azufre/química , Compuestos Heterocíclicos/química , Indoles/síntesis química , Nitrógeno/química
19.
Artículo en Inglés | MEDLINE | ID: mdl-23983378

RESUMEN

Traditional medicines have become the most productive source of leads for drugs development, particularly as anti-cancer agents. Various screening approaches are being applied. Sorafenib, a multikinase inhibitor, is used to treat primary kidney cancer (advanced renal cell carcinoma) and advanced primary liver cancer. A small library of compounds analogous to sorafenib were designed and screened for the treatment of liver cancer. Multiple members of the family in an assay panel of tyrosine kinase family and serine/threonine-protein kinase family, including VEGFR, Abl, Aurora A, p 38, Lck, Src, PDGFR, Flt3, c-RAF, c-KIT, MEK(MAPKK) were selected to test these compounds. Analysis of the selectivity patterns for these compounds shows specificity for many kinase families. IC50 were measured for the selected compounds. Multiple compounds have very similar kinase inhibition profiles of VEGFR, Flt3, FGFR to that of sorafenib. The IC50 of c-RAF of BB1 is lower than sorafenib. The IC50 of c-RAF of BB3-12 is higher than that of sorafenib. For Flt3, IC50 of BB1-4 is less than sorafenib. The IC50 value of KDR of BB1-10 is less than sorafenib. especially against c-RAF, PDGFR, c-KIT, KDR compared to sorafenib. These compounds are potent Raf1 and Flt4 kinase inhibitors.


Asunto(s)
Antineoplásicos/farmacología , Productos Biológicos/farmacología , Neoplasias Hepáticas/enzimología , Niacinamida/análogos & derivados , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Antineoplásicos/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Medicina Tradicional , Niacinamida/farmacología , Niacinamida/uso terapéutico , Compuestos de Fenilurea/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Sorafenib
20.
Chin Med J (Engl) ; 124(13): 1933, 2011 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-22088449

RESUMEN

BACKGROUND: The preclinical experiments and studies of congener drugs show icotinib, a new epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor, can specifically bind to the tyrosine kinase domain of the EGFR, block the EGFR related signal, thereby inhibit the growth of tumor cell. The objective of this study was to investigate the safety, tolerability and dose-related biologic effects of icotinib in patients with non-small cell lung cancer (NSCLC) in a Chinese patient population. METHODS: This was an open-label, phase I, dose escalation, safety/tolerability trial of oral icotinib (100 to 400 mg), administered twice per day for 28-continuous-day cycles until disease progression or undue toxicity. RESULTS: Forty patients with stage IIIB (15%) or IV (85%) NSCLC were included in the study. They had mainly adenocarcinoma (85%), with a performance status (PS) of 0 (45%) or 1 (55%) and less than half the patients (45%) had histories of smoking and all were pretreated by at least one regimen of chemotherapy. Patients were assigned to three dose levels of 150 mg b.i.d, 200 mg b.i.d, or 125 mg t.i.d. The follow-up periods ranged from 5 to 80 weeks. Adverse events were found in 35% patients, most of which were mild and reversible. The adverse events mainly occurred in the first 4 weeks and included rash (25%), diarrhea, nausea and abdominal distention. One definite interstitial lung disease (ILD) was found in a patient in the dose of 200 mg b.i.d. According to an 8-week assessment, one (2.5%) patient receiving 150 mg gained complete response (CR) that persisted for 44 weeks, seven (17.50%) patients had partial remission (PR), and 18 (45%) patients had stable disease (SD). The objective response including CR + PR was 20%. The median time of progression-free survival for the 40 patients was 20 weeks (range: 12 to 32 weeks). The response was not affected by pathological type, history of smoking, or numbers of previous therapeutic regimens. No relationship between dose, response, adverse effect, or duration of the study was observed. CONCLUSIONS: Icotinib, given as oral twice daily, showed favorable safety and tolerability. Mild and reversible rash, diarrhea, and nausea were the main adverse events. Antitumor activity was obvious at each dose in heavily pretreated patients. Pharmacodynamic evaluations and further phase II/III trials are in progress.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Éteres Corona/uso terapéutico , Receptores ErbB/antagonistas & inhibidores , Quinazolinas/uso terapéutico , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Supervivencia sin Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad
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