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1.
J Acoust Soc Am ; 155(5): 3490-3504, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38804817

RESUMEN

Attenuation is the most difficult seafloor acoustic property to get, particularly at low to mid frequencies. For low velocity bottoms (LVB), it becomes even more challenging, due to its small attenuation and lower velocity (relative to the velocity of the adjacent water). The latter one causes a fatal "seafloor velocity-attenuation couplings" in geo-acoustic inversions. Thus, attenuation inversions for the LVB require an accurate seafloor velocity profile, especially the velocity in the LVB layer. The propagation of explosive sound in the Yellow Sea with a strong thermocline and a top LVB layer exhibits many prominent characteristics: modal dispersion (the ground wave, water wave, Airy phase), two groups of water waves at high frequencies, and the siphon effect which causes abnormally large sound transmission loss at selected frequencies, etc. These observations are used to precisely measure the critical frequency, the Airy frequency, Airy wave velocity, 1st mode group velocity, and to derive the velocities in the LVB layer and in the basement. Using inverted seafloor parameters, the source level-normalized transmission loss and the first mode decay rate in ranges up to 27.66 km, the sound attenuations in the LVB are derived for a frequency range of 13-5000 Hz.

2.
Plant Dis ; 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38085241

RESUMEN

Cowpea (Vigna unguiculata L.), a significant vegetable crop in China, holds particular prominence in the tropical island of Hainan. This region serves as the primary production area for the winter cultivation of cowpea. Phytoplasmas are an idiopathic parasitic pathogen and cannot be cultured in vitro. It is mainly transmitted by the insect vectors with the piercing and sucking mouthparts, such as leafhoppers, plant hoppers, and psyllids. (Kumari et al. 2019). On September 11, 2023, typical characteristics of phytoplasma diseases on cowpeas were observed in the experimental base of Hainan Academy of Agricultural Sciences (20°0'38.6964″N, 110°21'35.4024″E, Haikou City, Hainan Province, China), including reduced leaf size, chlorosis, and the development of broom-like branch deformities reminiscent, as depicted in Figure 1. At the same time, we found a large number of leafhoppers near the diseased plants, and we speculated that leafhoppers are the insect carriers that spread the disease. Following an on-site investigation, it was determined that the disease incidence ranges from 10% to 15%, leading to a consequential decrease of about 10% in yield, which is a potential disease that seriously threatens the cowpea industry in Hainan. Ten disease and healthy samples were meticulously collected and subsequently preserved at -80°C within the laboratory refrigerator. Three disease samples denoted as HNNKY-1, HNNKY-2, and HNNKY-3, were randomly chosen, and total DNA extraction was carried out employing the NuClean Plant Genomic DNA Kit (CWBIO, Taizhou, China), while three healthy samples were randomly selected as control. The 16S rRNA gene was amplified by PCR using the primer pairs P1/P7 (Schneider et al. 1995) and R16F2n / R16R2 (Lee et al. 1993) and the secA gene was amplified by PCR using the primer pairs secAfor1/secArev3 (Hodgetts et al. 2008). After agarose gel electrophoresis analysis, no DNA fragments were observed in the healthy leaf samples, whereas all three disease samples yielded amplification products. The PCR products were subsequently sequenced by Hainan Nanshan Biotech Co., Ltd., Haikou, China. After sequence analysis, it was found that the 16S rRNA gene and secA gene sequences HNNKY-1, HNNKY-2, and HNNKY-3 were identical to each other. We selected two gene sequences of strain HNNKY-3 to submission to the GenBank database, The length of the 16S rRNA gene sequence is 1193 base pairs, identified by the accession number OR666421, while the secA gene sequence is 825 base pairs in length, associated with the accession number OR661282. The phytoplasma strain HNNKY-3 was named 'Vigna unguiculata' witches'-broom phytoplasma. A BLAST analysis of the 16S rRNA gene revealed that strain HNNKY-3 displayed a 100% sequence match with 'Emilia sonchifolia' witches'-broom phytoplasma (MT420682), Peanut witches'-broom phytoplasma (OR239773), and 'Raphanus sativus' witches'-broom phytoplasma (OK491387). All of these phytoplasmas were classified within the 16SrII group. Based on the BLAST analysis of partial secA gene sequences, it was discerned that sequence homogeneity ranged from 99.27% to 99.74% among the studied sequences. These sequences were collectively classified as members of the 16SrII group. In addition, a phylogenetic tree was constructed by MEGA 11 (version 11.0.13) based on the 16Sr RNA gene and secA gene by the neighbor-joining method (Tamura et al. 2004). The results demonstrated the clustering of HNNKY-3 phytoplasma strains within the 16SrII group, as illustrated in Figures 2 and 3. A virtual RFLP analysis based on the 16S rRNA gene fragment of HNNKY-3 was conducted using the interactive online phytoplasma classification tool, iPhyClassifier (Zhao et al. 2009). The results indicated that the phytoplasma strain was the same as the reference pattern of the onion yellows phytoplasma of 16SrII-A (GenBank accession: L33765), and the similarity coefficient was 1.00. To best of our knowledge, this is the inaugural documentation of 16SrII Group-related phytoplasma infecting cowpea in Hainan, China, and lays the groundwork for further research on the dissemination of cowpea phytoplasma disease within China.

3.
Neurol Sci ; 43(1): 677-682, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34480243

RESUMEN

OBJECTIVE: To evaluate whether shorter door-to-needle times (DNT) with intravenous tissue plasminogen activator (tPA) for acute ischemic stroke are associated with improved 1-year outcomes in Chinese patients. METHODS: From August to September 2019, all first-ever ischemic stroke patients who were treated with intravenous tPA within 4.5 h of the time they were last known to be well from 232 hospitals in China were included. Patients were divided into four groups according to DNT time (≤ 45 min; 45-60 min; 60-90 min; > 90 min). All discharged patients would receive a telephone follow-up at 12-month after admission. Death and disability events were recorded. RESULTS: Finally, 2370 patients were analyzed. The median age was 65 years, 66.6% were male, and 2.4% were of ethnic minorities. In the 1-year follow-up, 211 patients died (8.9%; 95%CI: 7.8-10.0%). The patients (53.1%) had DNT times of longer than 45 min, compared with those treated within 45 min, did not have significantly higher 1-year mortality (8.9% vs 8.9% [absolute difference, 0.03% {95% CI, - 0.05% to - 0.10%}, odd ratio {OR}, 1.00 {95% CI, 0.75 to 1.33}]). In addition, 385 patients (16.2%; 14.8-17.3%) out of those survivors had disability events. The patients had DNT times of longer than 45 min, compared with those treated within 45 min, did not have significantly higher 1-year disability rate (18.9% vs 16.7% [absolute difference, 1.9% {95% CI, 1.1% to 3.0%}, odd ratio {OR}, 1.22 {95% CI, 0.89 to 1.43}]). CONCLUSIONS: The results did not show that shorter DNT for tPA administration was significantly associated with better 1-year outcomes.


Asunto(s)
Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Anciano , Isquemia Encefálica/complicaciones , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/epidemiología , Minorías Étnicas y Raciales , Fibrinolíticos/uso terapéutico , Humanos , Masculino , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/epidemiología , Terapia Trombolítica , Tiempo de Tratamiento , Activador de Tejido Plasminógeno/uso terapéutico , Resultado del Tratamiento
4.
BMC Neurol ; 21(1): 9, 2021 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-33413173

RESUMEN

BACKGROUND: Antiphospholipid syndrome (APS) is associated with a high incidence of thrombotic events, either arterial thrombosis or venous thrombosis. However, APS-related non-thrombotic venous stenosis is rarely reported. CASE PRESENTATION: This study described two cases of young women with APS-related internal jugular vein stenosis (IJVS) and reviewed current literature on this issue, including clinical features, diagnosis, and treatment. CONCLUSIONS: IJVS is a rather rare complication of APS. Two cases were reported for the first time that high titer of antiphospholipid antibodies (aPL) might mediate direct vessel wall damage and further induce venous stenosis despite long-term standardized anticoagulation to prevent thrombus formation. Therefore, dynamic monitoring of autoantibodies and concomitant use of anticoagulants and corticosteroids may be necessary to the management of APS and its complications.


Asunto(s)
Síndrome Antifosfolípido/complicaciones , Venas Yugulares/patología , Trombosis de la Vena/etiología , Adulto , Síndrome Antifosfolípido/diagnóstico , Constricción Patológica/etiología , Femenino , Humanos
5.
J Asian Nat Prod Res ; 23(8): 803-808, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32614676

RESUMEN

A new aurone named (2Z)-2-[(4'-hydroxy-3'-methoxyphenyl) methylene]-6-methoxy-7-prenyl-3(2H)-benzofurane (1), together with five known compounds (2-6), were isolated from EtOAc-soluble extract of the stems of Acanthopanax senticosus. The chemical structures were elucidated on the basis of spectroscopic analyses. All isolates were evaluated for in vitro inhibitory activity on α-glucosidase. Among them, compounds 1 and 4 were found to exhibit moderate inhibitory activity on α-glucosidase with IC50 value of 64.1 ± 1.2 and 48.9 ± 1.1 µM, respectively.[Formula: see text].


Asunto(s)
Eleutherococcus , Estructura Molecular , Extractos Vegetales , alfa-Glucosidasas
6.
J Vasc Surg ; 72(2): 597-602, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31882308

RESUMEN

OBJECTIVE: Relatively little is known about the natural history of atherosclerotic common carotid artery occlusion and optimal treatment of these patients is still unclear. The aim of this retrospective study was to evaluate the immediate- and long-term outcomes of axillary to carotid bypass with polytetrafluoroethylene graft for symptomatic patients with chronic common carotid artery occlusion. METHODS: From March 2001 to December 2017, 58 symptomatic patients (41 men; mean age 64.7 years) with chronic common carotid artery occlusion underwent axillary to carotid bypass at one academic hospital. The clinical data of this patient cohort were retrospectively analyzed. The cumulative graft patency, overall survival, freedom from symptoms, and freedom from ipsilateral stroke were calculated with Kaplan-Meier method. RESULTS: Thirty-three patients presented with transient ischemic attack and 25 patients presented with minor stroke. At 30 days after bypass, the overall perioperative complication rate was 3.4% (2/58). Mild injuries of brachial plexus occurred in one (1.7%) patient and myocardial infarction occurred in one (1.7%) patient. No perioperative stroke or death occurred. The median follow-up was 51 months (range, 12-203) for this series. The cumulative graft patency rates at 1, 3, 5, and 10 years were 100%, 100%, 94%, and 83%, respectively. The cumulative freedom from symptoms rates at 1, 3, 5, and 10 years were 100%, 100%, 94%, and 75%, respectively. The cumulative freedom from ipsilateral stroke rates at 1, 3, 5, and 10 years were 100%, 100%, 94%, and 82%, respectively. The overall survival rates at 1, 3, 5, and 10 years were 98%, 89%, 81%, and 67%, respectively. CONCLUSIONS: Axillary to carotid bypass with polytetrafluoroethylene graft is safe and durable for symptomatic patients with chronic common carotid artery occlusion. The results of this study should be confirmed with a larger, randomized controlled trial in future.


Asunto(s)
Arteria Axilar/cirugía , Implantación de Prótesis Vascular , Arteria Carótida Común/cirugía , Estenosis Carotídea/cirugía , Anciano , Arteria Axilar/diagnóstico por imagen , Arteria Axilar/fisiopatología , Prótesis Vascular , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Arteria Carótida Común/diagnóstico por imagen , Arteria Carótida Común/fisiopatología , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/fisiopatología , Enfermedad Crónica , Humanos , Ataque Isquémico Transitorio/etiología , Masculino , Persona de Mediana Edad , Politetrafluoroetileno , Diseño de Prótesis , Estudios Retrospectivos , Accidente Cerebrovascular/etiología , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular
7.
Bioorg Med Chem ; 28(8): 115405, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-32156499

RESUMEN

In this study, we synthesized a series of double-component O2-aryl diazeniumdiolate (DDNO) derivatives, of which each molecule can release up to four nitric oxide molecules. These compounds showed cytotoxic activities to cancer cells, such as human leukemia, breast cancer and lung cancer. Among them, compound 1 (DDNO-1) showed the highest specific activity to human leukemia cells. It induced cell apopotosis and arrest cell cycle of G2/M phase. The JNK and p38 protein kinases were activated by compound 1 to induce cancer cell apoptosis. Compound 1 also increased pro-apoptotic Bax level, which is a same function compared to a reported NO donor, JS-K. More interestingly, it decreased the level of an anti-apoptotic member Bcl-2, which is an opposite effect compared to JS-K. Compound 1 could be developed as a new anti-cancer agent since it increases the Bax/Bcl-2 ratio to overcome the drug resistance.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Compuestos Azo/química , Puntos de Control del Ciclo Celular/efectos de los fármacos , Antineoplásicos/química , Apoptosis , Línea Celular Tumoral , Diseño de Fármacos , Humanos , Estructura Molecular
8.
Bioorg Med Chem ; 28(17): 115642, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32773093

RESUMEN

DNA polymerase ß (Pol ß) repairs cellular DNA damage. When such damage is inflicted upon the DNA in tumor cells treated with DNA targeted antitumor agents, Pol ß thus diminishes their efficacy. Accordingly, this enzyme has long been a target for antitumor therapy. Although numerous inhibitors of the lyase activity of the enzyme have been reported, none has yet proven adequate for development as a therapeutic agent. In the present study, we developed a new strategy to identify lyase inhibitors that critically engage the lyase active site primary nucleophile Lys72 as part of the binding interface. This involves a parallel evaluation of the effect of the inhibitors on the wild-type DNA polymerase ß (Pol ß) and Pol ß modified with a lysine analogue at position 72. A model panel of five structurally diverse lyase inhibitors identified in our previous studies (only one of which has been published) with unknown modes of binding were used for testing, and one compound, cis-9,10-epoxyoctadecanoic acid, was found to have the desired characteristics. This finding was further corroborated by in silico docking, demonstrating that the predominant mode of binding of the inhibitor involves an important electrostatic interaction between the oxygen atom of the epoxy group and Nε of the main catalytic nucleophile, Lys72. The strategy, which is designed to identify compounds that engage certain structural elements of the target enzyme, could find broader application for identification of ligands with predetermined sites of binding.


Asunto(s)
ADN Polimerasa beta/metabolismo , Ácidos Esteáricos/metabolismo , Sitios de Unión , Dominio Catalítico , ADN Polimerasa beta/antagonistas & inhibidores , ADN Polimerasa beta/genética , Humanos , Ligandos , Simulación del Acoplamiento Molecular , Mutagénesis Sitio-Dirigida , Unión Proteica , Ácidos Esteáricos/química
9.
J Am Chem Soc ; 141(14): 5597-5601, 2019 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-30889951

RESUMEN

Genetic code expansion has enabled many noncanonical amino acids to be incorporated into proteins in vitro and in cellulo. These have largely involved α-l-amino acids, reflecting the substrate specificity of natural aminoacyl-tRNA synthetases and ribosomes. Recently, modified E. coli ribosomes, selected using a dipeptidylpuromycin analogue, were employed to incorporate dipeptides and dipeptidomimetics. Presently, we report the in cellulo incorporation of a strongly fluorescent oxazole amino acid (lacking an asymmetric center or α-amino group) by using modified ribosomes and pyrrolysyl-tRNA synthetase (PylRS). Initially, a plasmid encoding the RRM1 domain of putative transcription factor hnRNP LL was cotransformed with plasmid pTECH-Pyl-OP in E. coli cells, having modified ribosomes able to incorporate dipeptides. Cell incubation in a medium containing oxazole 2 resulted in the elaboration of RRM1 containing the oxazole. Green fluorescent protein, previously expressed in vitro with several different oxazole amino acids at position 66, was also expressed in cellulo containing oxazole 2; the incorporation was verified by mass spectrometry. Finally, oxazole 2 was incorporated into position 13 of MreB, a bacterial homologue of eukaryotic cytoskeletal protein actin F. Modified MreB expressed in vitro and in cellulo comigrated with wild type. E. coli cells expressing the modified MreB were strongly fluorescent and retained the E. coli cell rod-like phenotype. For each protein studied, the incorporation of oxazole 2 strongly increased oxazole fluorescence, suggesting its potential utility as a protein tag. These findings also suggest the feasibility of dramatically increasing the repertoire of amino acids that can be genetically encoded for protein incorporation in cellulo.


Asunto(s)
Aminoácidos/química , Colorantes Fluorescentes/química , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/química , Oxazoles/química , Escherichia coli/metabolismo , Ribosomas/metabolismo
10.
Sensors (Basel) ; 18(10)2018 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-30241365

RESUMEN

Visual homing is an attractive autonomous mobile robot navigation technique, which only uses vision sensors to guide the robot to the specified target location. Landmark is the only input form of the visual homing approaches, which is usually represented by scale-invariant features. However, the landmark distribution has a great impact on the homing performance of the robot, as irregularly distributed landmarks will significantly reduce the navigation precision. In this paper, we propose three strategies to solve this problem. We use scale-invariant feature transform (SIFT) features as natural landmarks, and the proposed strategies can optimize the landmark distribution without over-eliminating landmarks or increasing calculation amount. Experiments on both panoramic image databases and a real mobile robot have verified the effectiveness and feasibility of the proposed strategies.

11.
Int J Nurs Pract ; 22(5): 478-485, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27325472

RESUMEN

The aim of this study is to examine the burden of family caregivers of patients with retinoblastoma in China and the relationships between depression, caregiver burden and social support. A descriptive and correlational survey was conducted with 117 Chinese family caregivers of outpatient patients with retinoblastoma from the Department of Ophthalmology of a tertiary hospital in Shanghai, China. Family caregivers of outpatient patients with retinoblastoma were asked to respond to four questionnaires including sociodemographic questionnaire, Becker Depression Inventory, Caregiver Burden Inventory and Social Support Rating Scale. The incidence of depression in this study was 51.3%; the average score for social support indicated moderate social support available to the caregivers, although their level of caregiver burden was heavy. Depression scores were significantly positively correlated with caregiver burden scores and significantly negatively correlated with the social support scores. Heavy caregiver burden was associated with lower monthly income, low subjective social support and less use of social support.


Asunto(s)
Cuidadores/psicología , Depresión , Retinoblastoma/enfermería , Apoyo Social , Adulto , China , Depresión/epidemiología , Femenino , Humanos , Masculino , Prevalencia
12.
J Insect Sci ; 15: 180, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25700538

RESUMEN

The wasp Spalangia endius Walker (Hymenoptera: Pteromalidae) is a major parasitoid of the pupae of fruit flies, which are a common agricultural pest. An understanding of this intricate host-parasitoid interaction could provide basic information necessary for the sustainable integrated biological control of fruit flies. In this study, we investigated the effect of S. endius on different-aged pupae of the melon fly Bactrocera cucurbitae Coquillett by using choice and nonchoice tests under laboratory conditions. We showed that S. endius females oviposited, and their progeny successfully developed, in different-aged pupae of B. cucurbitae regardless of the method of exposure. There was an oviposition preference for 3-5-d-old pupa. The highest mean percentage parasitism occurred on 4- and 5-d-old hosts, followed by 2- and 3-d-old hosts. The average development time for both males and females was significantly longer in 6-7-d-old hosts than in the younger host stages. Adult females that developed from younger host pupae (2-5-d old) were significantly heavier than those from older host pupae (6-7-d old), and they also lived longer. The sex ratio (proportion of females) of the parasite progeny decreased with an increase in host age. Host mortality also decreased gradually as the pupal age increased. The differences in development time, body weight, and longevity between females and males were significant. These results suggest that S. endius is a good candidate for the biological control of B. cucurbitae.


Asunto(s)
Oviposición/fisiología , Tephritidae/parasitología , Avispas/fisiología , Factores de Edad , Animales , Femenino , Longevidad , Masculino , Control Biológico de Vectores/métodos , Pupa/parasitología , Razón de Masculinidad , Avispas/embriología , Avispas/crecimiento & desarrollo
13.
Bioorg Med Chem ; 22(21): 6146-55, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25261927

RESUMEN

A series of 4-anilinothieno[2,3-d]pyrimidine-based hydroxamic acid derivatives as novel HDACs inhibitors were designed, synthesized and evaluated. Most of these compounds displayed good to excellent inhibitory activities against HDAC1, 3, 6. The IC50 values of compound 10r against HDAC1, HDAC3, HDAC6 was 1.14 ± 0.03 nM, 3.56 ± 0.08 nM, 11.43 ± 0.12 nM. Compound 10r noticeably up-regulated the level of histone H3 acetylation compared to the SAHA. Most of the compounds showed the strong anti-proliferative activity against human cancer cell lines including RMPI8226 and HCT-116. The IC50 values of Compounds 10r and 10t against RPMI8226 was 2.39 ± 0.20 µM, 1.41 ± 0.44 µM, respectively, and the HCT-116 was sensitive to the compounds 10h, 10 m, 10r, 10 w with the IC50 values <1.9 µM.


Asunto(s)
Antineoplásicos/química , Inhibidores de Histona Desacetilasas/química , Ácidos Hidroxámicos/química , Pirimidinas/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Humanos , Ácidos Hidroxámicos/farmacología , Simulación del Acoplamiento Molecular , Neoplasias/tratamiento farmacológico , Neoplasias/enzimología , Pirimidinas/farmacología , Relación Estructura-Actividad
14.
Bioorg Med Chem ; 22(23): 6684-6693, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25457126

RESUMEN

A series of (R)-3-amino-1-((3aS,7aS)-octahydro-1H-indol-1-yl)-4-(2,4,5-trifluorophenyl)butan-1-one derivatives was designed, synthesized, and evaluated as novel inhibitors of dipeptidyl peptidase-4 (DPP-4) for the treatment of type 2 diabetes. Most of the synthesized compounds demonstrated good inhibition activities against DPP-4. Among these, compounds 3e, 4c, 4l, and 4n exhibited prominent inhibition activities against DPP-4, with IC50s of 0.07, 0.07, 0.14, and 0.17µM, respectively. The possible binding modes of compounds 3e and 4n with dipeptidyl peptidase-4 were also explored by molecular docking simulation. These potent DPP-4 inhibitors were optimized for the absorption, distribution, metabolism, and excretion (ADME) properties, and compound 4n displayed an attractive pharmacokinetic profile (F=96.3%, t1/2=10.5h).


Asunto(s)
Dipeptidil Peptidasa 4/metabolismo , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Indoles/farmacología , Modelos Moleculares , Sulfonamidas/farmacología , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Humanos , Indoles/síntesis química , Indoles/química , Estructura Molecular , Proteínas Recombinantes/metabolismo , Relación Estructura-Actividad , Sulfonamidas/síntesis química , Sulfonamidas/química
15.
Bioorg Med Chem ; 22(7): 2366-78, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-24565969

RESUMEN

A novel series of 6-alkenylamides of 4-anilinothieno[2,3-d]pyrimidine derivatives was designed, synthesized and evaluated as irreversible inhibitors of the epidermal growth factor receptor (EGFR). Most of the compounds exhibited good potency against EGFR wild type (EGFR wt) and EGFR T790M/L858R. Among these, the half-maximal inhibitory concentration (IC50) values of 17 compounds against EGFR wt were less than 0.020µM, and those of 12 compounds were less than 0.010µM. The IC50 values of 10 compounds against EGFR T790M/L858R were less than 0.005µM. Compounds 8l, 9n, 9o, 9q and 9v almost completely blocked the phosphorylation of EGFR in the A431 cell line at 1µM. Compounds 8l, 9n, 9o, 9q and 9v blocked the autophosphorylation of EGFR in NCI-H1975 cells at high concentration (1µM), and compound 8l was confirmed to be an irreversible inhibitor through the dilution method.


Asunto(s)
Amidas/química , Antineoplásicos/farmacología , Diseño de Fármacos , Receptores ErbB/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Tiofenos/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Receptores ErbB/genética , Humanos , Estructura Molecular , Inhibidores de Proteínas Quinasas/síntesis química , Inhibidores de Proteínas Quinasas/química , Pirimidinas/síntesis química , Pirimidinas/química , Relación Estructura-Actividad , Tiofenos/síntesis química , Tiofenos/química
16.
Int J Mol Sci ; 15(6): 10999-1012, 2014 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-24945310

RESUMEN

It is well known that cobalt chloride (CoCl2) can enhance the stability of hypoxia-inducible factor (HIF)-1α. The aim of this study is to detect the effect of CoCl2 on the hypoxia tolerance of mice which were repeatedly exposed to autoprogressive hypoxia. Balb/c mice were randomly divided into groups of chemical pretreatment and normal saline (NS), respectively injected with CoCl2 and NS 3 h before exposure to hypoxia for 0 run (H0), 1 run (H1), and 4 runs (H4). Western Blot, electrophoretic mobility shift assay (EMSA), extracellular recordings population spikes in area cornus ammonis I (CA 1) of mouse hippocampal slices and real-time were used in this study. Our results demonstrated that the tolerance of mice to hypoxia, the changes of HIF-1α protein level and HIF-1 DNA binding activity in mice hippocampus, the mRNA level of erythropoietin (EPO) and vascular endothelial growth factor (VEGF), and the disappearance time of population spikes of hippocampal slices were substantially different between the control group and the CoCl2 group. Over-induction of HIF-1α by pretreatment with CoCl2 before hypoxia did not increase the hypoxia tolerance.


Asunto(s)
Cobalto/farmacología , Hipocampo/efectos de los fármacos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Hipoxia , Animales , ADN/metabolismo , Eritropoyetina/genética , Eritropoyetina/metabolismo , Hipocampo/metabolismo , Técnicas In Vitro , Masculino , Ratones , Ratones Endogámicos BALB C , Modelos Animales , Unión Proteica , ARN Mensajero/metabolismo , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(9): 2472-5, 2014 Sep.
Artículo en Zh | MEDLINE | ID: mdl-25532347

RESUMEN

The expansion dynamics of air plasma induced by 1,064 nm nanosecond laser pulse was studied by plasma fluorescence method. The time evolution images of air plasma expansion were acquired using the ICCD camera at different laser pulse energy, and the expansion velocity of air plasma was deduced based on the air plasma frontier expansion wave front distance at 150 mJ. The experimental results show that the plasma fluorescence was mainly distributed in the plasma expansion region, the plasma fluorescence intensity firstly increased then became weaker and the expansion area increased gradually with time evolution. The biggest expansion distance was 3. 76 mm with 300 mi at 20 ns. The plasma expansion speed was the order of magnitude of 10s m · s(-1) at the early stage of expansion process. The expansion speed of air plasma decayed rapidly within 16ns, then changed slowly with time. The time of air breakdown was close to the rising phase of laser pulse when the greater laser pulse energy was radiated.

18.
PhytoKeys ; 238: 85-94, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38361981

RESUMEN

Pipermotuoense X.W.Qin, F.Su & C.Y.Hao, a new species of Piperaceae from Xizang, China, is described and illustrated in this paper. The new species resembles P.yinkiangense and P.anisotis, but it can be readily distinguished from the compared species by several characteristics. Gonophyll leaves are chartaceous and the leaf secondary vein count is 7-9, with the outermost pair being very weak when there are nine veins. Additionally, the apical pair arises 2-4 cm above the base and the leaf base is asymmetrical, with bilateral petioles that cling and heal together. Pistillate floral bracts are sessile, with 3, 4 or 5 stigmas. The description of the new species includes photographs, detailed descriptions, notes on etymology, distribution and habitat, as well as comparisons with morphologically similar species.

19.
World J Pediatr ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951456

RESUMEN

BACKGROUND: Moyamoya disease (MMD) is a significant cause of childhood stroke and transient ischemic attacks (TIAs). This study aimed to assess the safety and efficacy of remote ischemic conditioning (RIC) in children with MMD. METHODS: In a single-center pilot study, 46 MMD patients aged 4 to 14 years, with no history of reconstructive surgery, were randomly assigned to receive either RIC or sham RIC treatment twice daily for a year. The primary outcome measured was the cumulative incidence of major adverse cerebrovascular events (MACEs). Secondary outcomes included ischemic stroke, recurrent TIA, hemorrhagic stroke, revascularization rates, and clinical improvement assessed using the patient global impression of change (PGIC) scale during follow-up. RIC-related adverse events were also recorded, and cerebral hemodynamics were evaluated using transcranial Doppler. RESULTS: All 46 patients completed the final follow-up (23 each in the RIC and sham RIC groups). No severe adverse events associated with RIC were observed. Kaplan-Meier analysis indicated a significant reduction in MACEs frequency after RIC treatment [log-rank test (Mantel-Cox), P = 0.021]. At 3-year follow-up, two (4.35%) patients had an ischemic stroke, four (8.70%) experienced TIAs, and two (4.35%) underwent revascularization as the qualifying MACEs. The clinical improvement rate in the RIC group was higher than the sham RIC group on the PGIC scale (65.2% vs. 26.1%, P < 0.01). No statistical difference in cerebral hemodynamics post-treatment was observed. CONCLUSIONS: RIC is a safe and effective adjunct therapy for asymptomatic children with MMD. This was largely due to the reduced incidence of ischemic cerebrovascular events.

20.
J Org Chem ; 78(9): 4312-8, 2013 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-23557210

RESUMEN

An efficient and facile Au(I)/Ag(I)-catalyzed cascade method has been developed for one-pot synthesis of the complex polycyclic heterocycles benzo[4,5]imidazo[1,2-c]pyrrolo[1,2-a]quinazolinone derivatives through treatment of the substituted 2-(1H-benzo[d]imidazol-2-yl)anilines with 4-pentynoic acid or 5-hexynoic acid. The strategy features a Au(I)/Ag(I)-catalyzed one-pot cascade process involving the formation of three new C-N bonds in high yields, and with broad a substrate scope.


Asunto(s)
Oro/química , Imidazoles/síntesis química , Compuestos Organometálicos/química , Pirroles/síntesis química , Quinazolinonas/síntesis química , Plata/química , Catálisis , Técnicas de Química Sintética , Imidazoles/química , Estructura Molecular , Pirroles/química , Quinazolinonas/química
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