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1.
Bioconjug Chem ; 31(10): 2293-2302, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-32786366

RESUMO

Glycosylation is a promising strategy for modulating the physicochemical properties of peptides. However, the influence of glycosylation on the biological activities of peptides remains unknown. Here, we chose the bee venom peptide HYL as a model peptide and 12 different monosaccharides as model sugars to study the effects of glycosylation site, number, and monosaccharide structure on the biochemical properties, activities, and cellular selectivities of HYL derivatives. Some analogues of HYL showed improvement not only in cell selectivity and proteolytic stability but also in antitumor and antimicrobial activity. Moreover, we found that the helicity of glycopeptides can affect its antitumor activity and proteolytic stability, and the α-linked d-monosaccharides can effectively improve the antitumor activity of HYL. Therefore, it is possible to design peptides with improved properties by varying the number, structure, and position of monosaccharides. What's more, the glycopeptides HYL-31 and HYL-33 show a promising prospect for antitumor and antimicrobial drugs development, respectively. In addition, we found that the d-lysine substitution strategy can significantly improve the proteolytic stability of HYL. Our new approach provides a reference or guidance for the research of novel antitumor and antimicrobial peptide drugs.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Antineoplásicos/farmacologia , Venenos de Abelha/química , Animais , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Antineoplásicos/química , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Abelhas/química , Linhagem Celular Tumoral , Glicosilação , Neoplasias/tratamento farmacológico
2.
Zhongguo Zhong Yao Za Zhi ; 44(6): 1110-1118, 2019 Mar.
Artigo em Zh | MEDLINE | ID: mdl-30989972

RESUMO

Chinese herbal medicines( CHMs) are a class of preparations made from natural plants that pose health beneficial properties as well as illness prevention functions. Thanks to a panel of salutary features,such as comprehensive immunological enhancement and inhibition of pathogenic bacteria,negligible side-effects,inappreciable drug-resistance,CHMs have been taken as one of the costeffective candidates for antibiotics substitutions. Through probiotics fermentation,the enzymatic hydrolysis of matrixes of CHMs enables easier release of the active ingredient as well as endows less toxicity of the preparations derived. During fermentation,the macromolecule or polymers forms of the active ingredient can be cut down to smaller molecule,which favors the transmembrane transport and improve adsorption of the active ingredients by the tissues. Other than the enzymatic benefits,probiotics can produce metabolites that inhibit pathogenic bacteria propagation,which may function synergically with the inhibitory effects of the CHMs preparations to fight the target pathogens. In addition,the oligosaccharide like components of CHMs can promote the growth of probiotics in intestinal environment which may largely facilitate the gut health. To summarize,the fermentation of CHMs using probiotics brings about the biochemical reactions and elevates the health beneficial effects by synergy of the microbial and herbal activities. It has been proved to be one of promising approaches as to antibiotic substitutions,particularly in livestock and poultry breeding industries. This review covered the recent progress of CHMs fermentation on the aspects of microbial strains,patterns of fermentation and active substances from fermentation of CHMs and their potency,respectively.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Medicamentos de Ervas Chinesas , Fermentação , Humanos , Pesquisa
3.
Behav Res Methods ; 50(4): 1496-1502, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29532446

RESUMO

Because they were used for decades to present visual stimuli in psychophysical and psychophysiological studies, cathode ray tubes (CRTs) used to be the gold standard for stimulus presentation in vision research. Recently, as CRTs have become increasingly rare in the market, researchers have started using various types of liquid-crystal display (LCD) monitors as a replacement for CRTs. However, LCDs are typically not cost-effective when used in vision research and often cannot reach the full capacity of a high refresh rate. In this study we measured the temporal and spatial characteristics of a consumer-grade LCD, and the results suggested that a consumer-grade LCD can successfully meet all the technical demands in vision research. The tested LCD, working in a flash style like that of CRTs, demonstrated perfect consistency for initial latencies across locations, yet showed poor spatial uniformity and sluggishness in reaching the requested luminance within the first frame. After these drawbacks were addressed through software corrections, the candidate monitor showed performance comparable or superior to that of CRTs in terms of both spatial and temporal homogeneity. The proposed solution can be used as a replacement for CRTs in vision research.


Assuntos
Tubo de Raio Catódico , Apresentação de Dados/normas , Desenho de Equipamento , Cristais Líquidos , Estimulação Luminosa , Humanos , Estimulação Luminosa/instrumentação , Estimulação Luminosa/métodos , Psicofísica , Psicofisiologia , Software , Análise Espaço-Temporal , Visão Ocular/fisiologia
4.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(8): 2017-20, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25474926

RESUMO

Qinghai caesious nephrite is discovered in the 1990s in the Golmud area of Qinghai Province. The conventional gemological testing methods, electron microprobe, infrared absorption spectroscopy and Raman spectroscopy were used in this study to analyze the chemical composition and infrared spectra characteristics of the caesious nephrite, selected from the jade mine of Xiaozhaohuo river in Golmud area. The results show that, the gemological physical properties of the Qinghai caesious nephrite are similar to other origin nephrite. Electron microprobe analysis indicates that the MgO, CaO and SiO2 are the major and stable composition for the caesious nephrite. The content of MgO and CaO are 18. 572%-23.603% and 12.333%-12.807% respectively. Moreover, the content of SiO2 is 56.799%-59.926%. In addition, it also contains a higher content of FeOr(Wt%: 1.924%-8.699%) and an amount of Al2O3, TiO2 and Na2O. Infrared absorption and Raman spectra show that the Qinghai caesious nephrite has a characteristic spectral features of tremolite indicating it is mainly composed of tremolite. The different frequency of the infrared absorption bands is due to the difference of Mg--Fe2+ isomorphous substitutionand Fe2+ content of the caesious nephrite. Comprehensive analysis of chemical composition and vibrational spectroscopy indicate that the color of dark gray blue for the Qinghai nephrite is mainly related to its high content of FeOr, and the Fe is a main coloring element.

5.
Atten Percept Psychophys ; 85(4): 1088-1105, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36823261

RESUMO

Previous studies have shown that during visual search, participants are able to implicitly learn across-trial regularities regarding target locations and use these to improve search performance. The present study asks whether such across-trial visual statistical learning also extends to the location of salient distractors. In Experiments 1 and 2, distractor regularities were paired so that a specific distractor location was 100% predictive of another specific distractor location on the next trial. Unlike previous findings that employed target regularities, the current results show no difference in search times between predictable and unpredictable trials. In Experiments 3-5 the distractor location was presented in a structured order (a sequence) for one group of participants, while it was presented randomly for the other group. Again, there was no learning effect of the across-trial regularities regarding the salient distractor locations. Across five experiments, we demonstrated that participants were unable to exploit across-trial spatial regularities regarding the salient distractors. These findings point to important boundary conditions for the modulation of visual attention by statistical regularities and they highlight the need to differentiate between different types of statistical regularities.


Assuntos
Aprendizagem Espacial , Humanos , Tempo de Reação
6.
Atten Percept Psychophys ; 85(1): 88-98, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36380146

RESUMO

Inhibition of return (IOR) discourages visual attention from returning to previously attended locations, and has been theorized as a mechanism to facilitate foraging in visual search by inhibitory tagging of inspected items. Previous studies using visual search and probe-detection tasks (i.e., the probe-following-search paradigm) found longer reaction times (RTs) for probes appearing at the searched locations than probes appearing at novel locations. This IOR effect was stronger in serial than parallel search, favoring the foraging facilitator hypothesis. However, evidence for this hypothesis was still lacking because no attempt was made to study how IOR would change when search efficiency gradually improves. The current study employed the probe-following-search paradigm and long-term training to examine how IOR varied following search efficiency improvements across training days. According to the foraging facilitator hypothesis, inhibitory tagging is an after-effect of attentional engagement. Therefore, when attentional engagement in a visual search task is reduced via long-term training, the strength of inhibitory tagging decreases, thus predicting a reduced IOR effect. Consistent with this prediction, two experiments consistently showed that IOR decreased while search efficiency improved through training, although IOR reached the floor more quickly than search efficiency. These findings support the notion that IOR facilitates search performance via stronger inhibitory tagging in more difficult visual search.


Assuntos
Inibição Psicológica , Humanos , Tempo de Reação/fisiologia
7.
J Exp Psychol Hum Percept Perform ; 48(3): 262-274, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35238597

RESUMO

Previous studies have shown that attention becomes biased toward those locations that frequently contain a target and is biased away from locations that have a high probability to contain a distractor. A recent study showed that participants also learned regularities that exist across trials: Participants were faster to find the singleton when its location was predicted by the location of the target singleton on the previous trial. Note, however, that this across-trial statistical learning was only demonstrated for parallel search involving "pop-out" singleton targets. The current study investigated whether there is also learning of across-trial regularities when search is serial, using a T-among-Ls task. In Experiment 1, using search displays with a gray T-target among gray Ls, we found that participants did not learn the existing across-trial regularities. In Experiment 2 we used the same display and same regularities except that during the first half of the experiment the targets were colored red, allowing feature search. Critically, now participants did learn the across-trial regularities during pop-out feature search and the learned biases persisted when search was serial again. Participants were not aware of these regularities suggesting that learning was automatic and implicit. We propose that across-trial target-target associations learned during feature search shape a flexible priority map whereby the selection of the predicting location results in up-weighting of the predicted location on the next trial. This flexible priority map remained active even when search task changed dramatically from parallel to serial search. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Assuntos
Atenção , Aprendizagem , Conscientização , Humanos , Tempo de Reação
8.
BMJ Open ; 12(8): e051594, 2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008072

RESUMO

Epidermal growth factor receptor (EGFR) is a therapeutic target in nasopharyngeal carcinoma (NPC). The optimal combined modality of optimal combined modality of anti--EGFR monoclonal antibodies, induction chemotherapy (ICT), concurrent chemotherapy and radiotherapy for NPC remains poorly defined. None of previous studies have developed subsequent treatment strategies on the basis of stratification according to the efficacy following ICT plus anti-EGFR mAbs. This study aims to increase treatment intensity for patients with poor efficacy of ICT and reduce treatment toxicity for patients with favourable efficacy of ICT by assessing whether the efficacy of this treatment regimen is non-inferior to ICT plus concurrent chemoradiotherapy (historic controls). INTRODUCTION: METHODS AND ANALYSIS: Pathology-confirmed WHO type II/III NPC patients at clinical stage III-IVA (eighth American Joint Committee on Cancer/Union for International Cancer Control staging system) will be included in the study. They will receive ICT plus nimotuzumab (NTZ), followed by radiotherapy plus NTZ or concurrent chemoradiotherapy plus NTZ (stratified based on the efficacy of ICT plus NTZ). The primary endpoint is 3-year failure-free survival rate; while the secondary endpoints are 3-year overall survival rate, distant metastasis-free survival rate and locoregional recurrence-free survival rate, and short-term remission rate of tumour and treatment toxicity. ETHICS AND DISSEMINATION: The study protocol has been approved by the Ethics Committee of the Second Affiliated Hospital of Nanchang University. Our findings will be disseminated in a peer-reviewed journal. Implementation strategies are in place to ensure privacy and confidentiality of participants. TRIAL REGISTRATION NUMBER: ChiCTR2000041139.


Assuntos
Antineoplásicos , Neoplasias Nasofaríngeas , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia/efeitos adversos , Ensaios Clínicos Fase II como Assunto , Humanos , Quimioterapia de Indução , Estudos Multicêntricos como Assunto , Carcinoma Nasofaríngeo/tratamento farmacológico , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/terapia , Estadiamento de Neoplasias , Estudos Prospectivos
9.
Psychiatry Res ; 185(1-2): 275-9, 2011 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-20542575

RESUMO

The Personal and Social Performance Scale (PSP) is a 100-point single-item rating scale that assesses four important domains of patients with mental disorders. This study was designed to examine the validity and reliability of a Chinese version of the PSP. The study was conducted in a sample of 157 patients with schizophrenia (confirmed by DSM-IV-TR criteria, SCID-P interview). The internal consistency (Cronbach's alpha=0.84) and the inter-rater reliability (kappa value=0.82, ICC=0.94 for PSP total score) was good. The test-retest reliability was high (intraclass correlation coefficient (ICC) of 0.95). The scale showed good construct validity with statistically significant correlations with the Global Assessment of Functioning Scale (GAF) (ICC of 0.95). The PSP score had a good negative correlation with the Positive and Negative Syndrome Scale (PANSS) total score. The improvement in PSP after 8 weeks of treatment was significantly correlated with the reduction in PANSS: after 8 weeks of treatment, the responders (defined as those with a reduction in PANSS total score ≥50%) experienced a greater improvement in PSP than the non-responders. The Chinese version of the PSP is a convenient and valid instrument to assess the personal and social functions of stabilized and acute patients with schizophrenia.


Assuntos
Transtornos Mentais , Personalidade/fisiologia , Comportamento Social , Tradução , Adulto , China/epidemiologia , Feminino , Humanos , Masculino , Transtornos Mentais/diagnóstico , Transtornos Mentais/epidemiologia , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Front Psychiatry ; 12: 717715, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34456770

RESUMO

Purpose: To compare the efficacy and tolerability of different administration strategies of aripiprazole. Methods: We searched MEDLINE, EMBASE, the Cochrane Central, Web of Science, China National Knowledge Infrastructure(CNKI), and Wanfang Data Knowledge Service Platform(Wanfang) for randomized controlled trials (RCTs) of aripiprazole, using the terms: (aripiprazole) AND (schizophr* OR schizoaff*) AND ("syndrome scale" OR PANSS) AND (clini* OR trial). We retrieved study design, participant characteristics, comparison groups, and outcomes from each study. Results: In total, nine RCTs were selected for meta-analysis, which covered ~1,187 participants. We defined two treatment groups that represent different treatment strategies: (1) the high-dose group (the high-dose strategy) rapidly increased to doses higher than 15 mg/day in 2 weeks or began with doses higher than 15 mg/day, otherwise the group was defined as (2) the low-dose group (the low-dose strategy). If the initial or target doses of aripiprazole in a study were all higher than 15 mg/day, the high- and low-dose groups were created based on the relative level of the dose. The high-dose group showed significantly greater reductions in Positive and Negative Syndrome Scale (PANSS) total scores (standardized mean differences = -8.31, 95% confidence interval [CI] = -16.48, -0.13; P < 0.01; I 2 = 96%) than the low-dose group. The high-dose group showed superior effects compared with the low-dose group in long-term studies (more than 8 weeks) (standardized mean differences = -13.81, 95% CI = -25.07, -2.55; P < 0.01; I 2 = 96%). With exception of somnolence, we did not find significant differences in side effects or discontinuation due to adverse events. Sensitivity analyses produced similar results. Conclusion: The high-dose treatment strategy of aripiprazole for patients with schizophrenia or schizoaffective disorder may bring more benefits without obvious side effects.

11.
Life (Basel) ; 11(11)2021 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-34833053

RESUMO

Plant parasitic nematodes (PPNs) are a pathogenic group that causes momentous crop yield loss by retarding plant growth and development through plant parasitization. In this study, the distribution of PPNs based on the main crops in Guangxi Province of China was investigated. A total of 425 samples of soil or roots from sugarcane, rice, maize, and soybean were collected in 68 counties, and a total of 48 order/family/genera of PPNs were identified, of which some genera were found in more than one crop. A total of 31 order/family/genera of PPNs were found in rice, among which Hirschmanniella was the most abundant, accounting for 79.23%, followed by Tylenchorhynchus (34.43%). Forty order/family/genera were observed in maize, of which the dominant genera were Pratylenchus and Tylenchorhynchus at 45.14% and 32.64%, respectively. In addition, 30 order/family/genera of PPNs were detected from sugarcane, and the percentages of Tylenchorhynchus and Helicotylenchus were 70.42% and 39.44%, respectively. The main crop of Eastern ecological regions was rice, with a high frequency of Hirschmanniella. The greatest frequency of Pratylenchus was found in the Western eco-region, which had a large area of maize. In the Northern eco-region, rice and maize were popular, with abundant Hirschmanniella and Helicotylenchus. In the Central eco-region, Pratylenchus was detected on the main crop of sugarcane. Hirschmanniella (72.94%) was dominant in clay, and Tylenchorhynchus (54.17%) showed the highest frequency in loam. The distribution of PPNs varied with different altitudes. The diversity of this phenomenon was closely related to host plants. These results could improve understanding of the distribution of PPNs and provide important information for controlling PPNs.

12.
J Exp Psychol Hum Percept Perform ; 46(8): 860-870, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32324032

RESUMO

Previous studies have shown that attentional selection can be biased toward locations that are likely to contain a target and away from locations that are likely to contain a distractor. It is assumed that through statistical learning, participants are able to extract the regularities in the display, which in turn biases attentional selection. The present study employed the additional singleton task to examine the ability of participants to extract regularities that occurred across trials. In four experiments, we found that participants were capable of picking up statistical regularities concerning target positions across trials both in the absence and presence of distracting information. It is concluded that through statistical learning, participants are able to extract intertrial statistical associations regarding subsequent target location, which in turn biases attentional selection. We argue here that the weights within the spatial priority map can be dynamically adapted from trial to trial such that the selection of a target at a particular location increases the weights of the upcoming target location within the spatial priority map, giving rise to a more efficient target selection. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Associação , Viés de Atenção/fisiologia , Aprendizagem por Probabilidade , Percepção Espacial/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
13.
Mol Ther Nucleic Acids ; 13: 580-589, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30439646

RESUMO

Long noncoding RNAs (lncRNAs) are closely associated with the molecular mechanisms underlying cancer development, and it would be highly useful to study their expression and mechanisms in cervical cancer too. The current study investigated lncRNA799 expression in cervical cancer in order to determine its clinical importance in the progression of cervical cancer. lncRNA799 expression was studied in 218 cervical cancer samples. Expression of lncRNA799 was significantly higher in the cervical cancer tissue than in the adjacent normal tissue. Overexpression of lncRNA799 was found to have a significant correlation with FIGO stage, SCC-Ag level, and lymphatic metastasis, and it was also associated with poor survival. Ectopic expression of lncRNA799 promoted the metastasis of SiHa cells, whereas lncRNA799 knockdown had an inhibitory effect on metastasis. Western blot analysis demonstrated that lncRNA799 promotes the expression of transducing ß-like protein 1-related protein (TBL1XR1), and that lncRNA799 and TBL1XR1 expression show strong correlation in cervical cancer. Moreover, lncRNA799 modulated the expression of TBL1XR1 by acting as a competitive endogenous RNA (ceRNA) for miR-454-3P. The results indicate that lncRNA799 could be used as a novel marker of cervical cancer prognosis. Thus, targeting the ceRNA network involving lncRNA799 could be a potential treatment strategy against cervical cancer.

14.
Front Psychol ; 9: 2403, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30564172

RESUMO

Inhibition of return (IOR) refers to slower responses to targets that occur at a previously attended location than to those at control locations. Previous studies on the impact of task difficulty on IOR have shown conflicting results. However, these studies failed to match low-level characteristics of stimuli (e.g., size, color, and luminance) across difficulty levels, and so might have confounded the effect of task difficulty with that of stimulus characteristics. Hence, whether and how task difficulty modulates IOR remain largely unknown. This study utilized the event-related potentials (ERPs) technique in combination with a cue-target paradigm to tackle this question. Task difficulty was manipulated by changing the position of a gap in a rectangle stimulus, while stimulus size, color, and luminance were precisely matched. IOR was observed in reaction times across all difficulty levels but was found in accuracy at the medium level only. The modulation effect of task difficulty on IOR was also evident in the N1 and P2 ERP components, which showed significantly weaker IOR effects at the medium difficulty level than at the easy and hard levels. It is suggested that the modulation of IOR by task difficulty involves both perceptual and post-perceptual processes.

15.
Front Psychol ; 8: 1562, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28955277

RESUMO

Inhibition of return (IOR) refers to slower responses to targets at a previously cued location than that at an uncued location. The time course of IOR has long been a topic of interest in the field. Investigations into the time course of IOR are typically performed by examining the magnitude of IOR under various cue-target onset asynchrony (CTOA) conditions. Therefore, the results are vulnerable to influence of factors that could affect the target processes (e.g., the frequency of the target type). In the present study, steady-state visual evoked potentials (SSVEPs) were implemented to directly take a continuous measurement of the degree to which cued location is processed, eliminating the influence mentioned above. The results indicate that, relative to the baseline interval (-400 to 0 ms), the presence of peripheral cues generated a typical two-stage effect on the SSVEP amplitude evoked by a 20 Hz flicker. Specifically, after the onset of the peripheral cues, the SSVEP amplitude first showed a significant increase, which subsequently turned into a significant inhibition effect after 200 ms. These results provide a continuous time course diagram of the cueing effect and suggest an effective way for future investigations of controlling the masking effects of target stimuli processing on IOR.

16.
Ying Yong Sheng Tai Xue Bao ; 22(6): 1485-92, 2011 Jun.
Artigo em Zh | MEDLINE | ID: mdl-21941749

RESUMO

By using light emitting diode (LED) to accurately modulate spectral energy distribution, and with fluorescent light as the control, this paper studied the effects of light quality on the seedlings growth and physiological characteristics of rice cultivars 'Wuyunjing 7' and 'Kangyou 63'. Light quality had significant effects on the seedlings growth, and there existed differences at different growth stages. Blue LED inhibited the height growth significantly, and increased the leaf soluble protein content of 'Wuyunjing 7' and the healthy index of the two rice cultivars at five-leaf stage. Red LED increased the stem diameter and healthy index at three-leaf stage and the leaf soluble sugar and starch contents at five-leaf stage significantly. Red-blue LED increased the root number, stem diameter, healthy index, root activity, and root soluble sugar content at three-leaf stage and the fresh mass, dry mass, healthy index, and leaf soluble sugar and sucrose contents at five-leaf stage significantly. Yellow LED increased the plant height and leaf pigment content at initial growth stage. Overall, red-blue LED was more beneficial to the culture of strong rice seedlings.


Assuntos
Luz , Oryza/crescimento & desenvolvimento , Oryza/efeitos da radiação , Plântula/crescimento & desenvolvimento , Plântula/efeitos da radiação , Oryza/fisiologia , Plântula/fisiologia
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