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1.
BMC Infect Dis ; 23(1): 182, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36991368

RESUMO

OBJECTIVE: To analyze the distribution of blaOXA among global Klebsiella pneumoniae and the characteristics of blaOXA-carrying K. pneumoniae. MATERIALS AND METHODS: The genomes of global K. pneumoniae were downloaded from NCBI by Aspera software. After quality check, the distribution of blaOXA among the qualified genomes was investigated by annotation with the resistant determinant database. The phylogenetic tree was constructed for the blaOXA variants based on the single nucleotide polymorphism (SNP) to explore the evolutionary relationship between these variants. The MLST (multi-locus sequence type) website and blastn tools were utilized to determine the sequence types (STs) of these blaOXA-carrying strains. and sample resource, isolation country, date and host were extracted by perl program for analyzing the characteristics of these strains. RESULTS: A total of 12,356 K. pneumoniae genomes were downloaded and 11,429 ones were qualified. Among them, 4386 strains were found to carry 5610 blaOXA variants which belonged to 27 varieties of blaOXAs, blaOXA-1 (n = 2891, 51.5%) and blaOXA-9 (n = 969, 17.3%) were the most prevalent blaOXA variants, followed by blaOXA-48 (n = 800, 14.3%) and blaOXA-232 (n = 480, 8.6%). The phylogenetic tree displayed 8 clades, three of them were composed of carbapenem-hydrolyzing oxacillinase (CHO). Totally, 300 distinct STs were identified among 4386 strains with ST11 (n = 477, 10.9%) being the most predominant one followed by ST258 (n = 410, 9.4%). Homo sapiens (2696/4386, 61.5%) was the main host for blaOXA-carrying K. pneumoniae isolates. The blaOXA-9-carrying K. pneumoniae strains were mostly found in the United States and blaOXA-48-carrying K. pneumoniae strains were mainly distributed in Europe and Asia. CONCLUSION: Among the global K. pneumoniae, numerous blaOXA variants were identified with blaOXA-1, blaOXA-9, blaOXA-48 and blaOXA-232 being the most prevalent ones, indicating that blaOXA rapidly evolved under the selective pressure of antimicrobial agents. ST11 and ST258 were the main clones for blaOXA-carrying K. pneumoniae.


Assuntos
Carbapenêmicos , Klebsiella pneumoniae , Humanos , Estados Unidos , Tipagem de Sequências Multilocus , Filogenia , Europa (Continente)
2.
BMC Microbiol ; 22(1): 255, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36266616

RESUMO

OBJECTIVE: To analyze the characteristics of global ß-lactamase-producing Enterobacter cloacae including the distribution of ß-lactamase, sequence types (STs) as well as plasmid replicons. METHODS: All the genomes of the E. cloacae were downloaded from GenBank. The distribution of ß-lactamase encoding genes were investigated by genome annotation after the genome quality was checked. The STs of these strains were analyzed by multi-locus sequence typing (MLST). The distribution of plasmid replicons was further explored by submitting these genomes to the genome epidemiology center. The isolation information of these strains was extracted by Per program from GenBank. RESULTS: A total of 272 out of 276 strains were found to carry ß-lactamase encoding genes. Among them, 23 varieties of ß-lactamase were identified, blaCMH (n = 130, 47.8%) and blaACT (n = 126, 46.3%) were the most predominant ones, 9 genotypes of carbapenem-hydrolyzing ß-lactamase (CHßLs) were identified with blaVIM (n = 29, 10.7%) and blaKPC (n = 24, 8.9%) being the most dominant ones. In addition, 115 distinct STs for the 272 ß-lactamase-carrying E. cloacae and 48 different STs for 106 CHßLs-producing E. cloacae were detected. ST873 (n = 27, 9.9%) was the most common ST. Furthermore, 25 different plasmid replicons were identified, IncHI2 (n = 65, 23.9%), IncHI2A (n = 64, 23.5%) and IncFII (n = 62, 22.8%) were the most common ones. Notably, the distribution of plasmid replicons IncHI2 and IncHI2A among CHßLs-producing strains were significantly higher than theat among non-CHßLs-producing strains (p < 0.05). CONCLUSION: Almost all the E. cloacae contained ß-lactamase encoding gene. Among the global E. cloacae, blaCMH and blaACT were main blaAmpC genes. BlaTEM and blaCTX-M were the predominant ESBLs. BlaKPC, blaVIM and blaNDM were the major CHßLs. Additionally, diversely distinct STs and different replicons were identified.


Assuntos
Enterobacter cloacae , beta-Lactamases , Enterobacter cloacae/genética , beta-Lactamases/genética , Tipagem de Sequências Multilocus , Testes de Sensibilidade Microbiana , Carbapenêmicos/farmacologia , Genômica
3.
Bioorg Med Chem ; 61: 116707, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35344835

RESUMO

PI3K kinase plays an important role in regulating key processes in cells, such as cell growth, metabolism, proliferation, and apoptosis. The overexpression of PI3K kinase exists in many cancers. The proteolytic target chimera (PROTAC) technology is a new technology that uses the ubiquitin-proteasome system to degrade a given target protein. It has been described that CRBN-based PROTAC targets the degradation of PI3K kinase. However, PROTAC based on VHL has not been reported yet. Here, we connected the previously obtained highly active PI3K inhibitor to the VHL ligand through different small molecules, and obtained a series of PROTAC molecules targeting PI3K kinase. Obtain the most active compound through screening. It provides evidence for the feasibility of PROTAC technology to recruit VHL E3 ligase in PI3K kinase.


Assuntos
Neoplasias , Ubiquitina-Proteína Ligases , Humanos , Fosfatidilinositol 3-Quinases/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Ubiquitina-Proteína Ligases/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo
4.
Pediatr Exerc Sci ; 34(1): 1-5, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34784580

RESUMO

PURPOSE: Using wearable monitoring devices is increasingly ubiquitous, including among young people. However, there is limited evidence of the validity of devices which are aimed at children and adolescents. The purpose of this study was to evaluate the validity of Fitbit Ace and Moki monitors in healthy young adolescents. METHODS: This cross-sectional study included 17 young adolescents (ages 11-13 y) ambulating between 3 different walking conditions (incidental [∼6 min], controlled, and treadmill [each 3 min], while wearing wrist-worn devices [Fitbit Ace, Moki] on each wrist [left and right, respectively]). Data from the devices were compared with observer counts (criterion). Bland-Altman plots and mean absolute percentage errors were computed. RESULTS: Analyses identified that the Fitbit Ace showed higher levels of bias across conditions compared with the Moki device: (mean difference [SD]; Fitbit Ace: 30.0 [38.0], 3.0 [13.0], and 13.0 [23.0] steps and Moki: 1.0 [19.0], 4.0 [16.0], and 6.0 [14.0] steps, incidental, controlled, and treadmill, respectively). Mean absolute percentage errors ranged from 3.1% to 9.5% for the Fitbit Ace and 3.0% to 4.0% for the Moki device. CONCLUSION: The Fitbit Ace and Moki devices might not provide acceptable validity under all walking conditions, but the Moki provides more accurate estimates of incidental walking and might therefore be a good choice for free-living research or school-based interventions.


Assuntos
Acelerometria , Dispositivos Eletrônicos Vestíveis , Adolescente , Criança , Estudos Transversais , Monitores de Aptidão Física , Humanos , Monitorização Ambulatorial , Reprodutibilidade dos Testes , Caminhada
5.
J Theor Biol ; 512: 110538, 2021 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-33189760

RESUMO

A honey bee can dip nectar of viscosity across two orders of magnitude, by viscous lapping technique using a segmental tongue covered with erectable hairs. The drinking technique suffers risks of leakage occurring between tongue hairs, and the amount of leakage is related to hair spacing as well as nectar viscosity. When lapping, tongue segments are elongated, which enlarges the hair spacing in longitudinal direction. Experimental observations show that the hair spacing of tongue increases with respect to sucrose solution concentration until it reaches the maximum extension when sucrose solution concentration is above 35%. Considering leakage occurring in the hairy tongue, we hypothesize that the dynamical extension of hair spacing may help honey bees minimize the effects of leakage to reach maximal nectar intake rate. A mathematical model is developed for determining the optimal hair spacing that can meet the demands of both augmenting the nectar intake rate and reducing the risk of leakage. Theoretical prediction and experimental measurements demonstrate honey bees are able to adjust the tongue to meet the optimal hair spacing when dipping nectar of concentration more dilute than 35% and maintain a maximum extension to improve the nectar intake rate when concentration is greater than 35%. We then give the prediction of concentration preferences of three bee species, and discuss effects of dipping frequency and gravity on the leakiness between tongue hairs. This work may not only gain insights into adaptive feeding strategy in insects, but inspire the design of adaptive microfluidic transport devices with dynamic brushy surfaces.


Assuntos
Néctar de Plantas , Língua , Animais , Abelhas , Comportamento Alimentar , Cabelo , Viscosidade
6.
Macromol Rapid Commun ; 42(17): e2100321, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34254396

RESUMO

Nonconventional luminogens with persistent room temperature phosphoresce (p-RTP) are attracting increasing attention owing to their momentous significance and diverse technical applications in optoelectronic and biomedical. So far, the p-RTP emission of some amorphous powders or single crystals has been studied in depth. The p-RTP emission of amorphous and fully crystalline states and their emission properties are widely divergent, while the difference of their p-RTP emission mechanism is still controversial. The relevance between crystallinity change and p-RTP properties is rarely studied. Furthermore, there is almost no research on the photoluminescence (PL) property change and emission mechanism under the crystal form transformation of semi-crystalline polymer. Herein, microcrystalline cellulose (MCC) is chosen as a model compound to explore its crystallinity and the change in luminescence during the crystal form transformation to make up for this gap. By precisely adjusting the crystallinity and crystal cellulose conversion of MCC, the changing trend of quantum efficiency, and p-RTP lifetime is consistent with the change of crystallinity, and the cellulose I may be more beneficial to PL emission than cellulose II. Clustering-triggered emission mechanism can reasonably explain these interesting photophysical processes, which also can be supported by single-crystal analysis and theoretical calculations.


Assuntos
Celulose , Luminescência
7.
Molecules ; 26(22)2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34834079

RESUMO

A series of novel fluorescent 4H-1-benzopyrans was designed and developed as near-infrared fluorescent molecules with a compact donor-acceptor-donor architecture. Spectral intensity of the fluorescent molecules M-1, M-2, M-3 varied significantly with the increasing polarities of solvents, where M-3 showed high viscosity sensitivity in glycerol-ethanol system with a 3-fold increase in emission intensity. Increasing concentrations of compound M-3 to 5% BSA in PBS elicited a 4-fold increase in fluorescence intensity, exhibiting a superior environmental sensitivity. Furthermore, the in vitro cellular uptake behavior and CLSM assay of cancer cell lines demonstrated that M-3 could easily enter the cell nucleus and bind to proteins with low toxicity. Therefore, the synthesized near-infrared fluorescent molecules could provide a new direction for the development of optical imaging probes and potential further drugs.

8.
J Exp Biol ; 222(Pt 21)2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31597733

RESUMO

The western honey bee, Apis mellifera L. (Hymenoptera), is arguably the most important pollinator worldwide. While feeding, A. mellifera uses a rapid back-and-forth motion with its brush-like mouthparts to probe pools and films of nectar. Because of the physical forces experienced by the mouthparts during the feeding process, we hypothesized that the mouthparts acquire wear or damage over time, which is paradoxical, because it is the older worker bees that are tasked with foraging for nectar and pollen. Here, we show that the average length of the setae (brush-like structures) on the glossa decreases with honey bee age, particularly when feeding on high-viscosity sucrose solutions. The nectar intake rate, however, remains nearly constant regardless of age or setae length (0.39±0.03 µg s-1 for honey bees fed a 45% sucrose solution and 0.48±0.05 µg s-1 for those fed a 35% sucrose solution). Observations of the feeding process with high-speed video recording revealed that the older honey bees with shorter setae dip nectar at a higher frequency. We propose a liquid transport model to calculate the nectar intake rate, energy intake rate and the power to overcome viscous drag. Theoretical analysis indicates that A. mellifera with shorter glossal setae can compensate both nectar and energy intake rates by increasing dipping frequency. The altered feeding behavior provides insight into how A. mellifera, and perhaps other insects with similar feeding mechanisms, can maintain a consistent fluid uptake rate, despite having damaged mouthparts.


Assuntos
Abelhas/fisiologia , Ingestão de Energia , Néctar de Plantas , Fatores Etários , Animais , Transporte Biológico , Fenômenos Biomecânicos , Comportamento Alimentar , Modelos Biológicos , Boca/anatomia & histologia , Boca/fisiologia , Língua/fisiologia , Viscosidade
9.
Mem Cognit ; 46(6): 923-939, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29679293

RESUMO

The current study investigated the contribution of phonology to bilingual language control in connected speech. Speech production was elicited by asking Mandarin-English bilinguals to read aloud paragraphs either in Chinese or English, while six words were switched to the other language in each paragraph. The switch words were either cognates or noncognates, and switching difficulty was measured by production of cross-language intrusion errors on the switch words (e.g., mistakenly saying (qiao3-ke4-li4) instead of chocolate). All the bilinguals were Mandarin-dominant, but produced more intrusion errors when target words were written in Chinese than when written in English (i.e., they exhibited robust reversed dominance effects). Most critically, bilinguals produced significantly more intrusions on Chinese cognates, but also detected and self-corrected these same errors more quickly than with noncognates. Phonological overlap boosts dual-language activation thus leading to greater competition between languages, and increased response conflict, thereby increasing production of intrusions but also facilitating error detection during speech monitoring.


Assuntos
Conflito Psicológico , Função Executiva/fisiologia , Multilinguismo , Psicolinguística , Leitura , Fala/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
10.
Brain Cogn ; 118: 27-44, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28753438

RESUMO

The current study investigated how Alzheimer's disease (AD) affects production of speech errors in reading-aloud. Twelve Spanish-English bilinguals with AD and 19 matched controls read-aloud 8 paragraphs in four conditions (a) English-only, (b) Spanish-only, (c) English-mixed (mostly English with 6 Spanish words), and (d) Spanish-mixed (mostly Spanish with 6 English words). Reading elicited language intrusions (e.g., saying la instead of the), and several types of within-language errors (e.g., saying their instead of the). Patients produced more intrusions (and self-corrected less often) than controls, particularly when reading non-dominant language paragraphs with switches into the dominant language. Patients also produced more within-language errors than controls, but differences between groups for these were not consistently larger with dominant versus non-dominant language targets. These results illustrate the potential utility of speech errors for diagnosis of AD, suggest a variety of linguistic and executive control impairments in AD, and reveal multiple cognitive mechanisms needed to mix languages fluently. The observed pattern of deficits, and unique sensitivity of intrusions to AD in bilinguals, suggests intact ability to select a default language with contextual support, to rapidly translate and switch languages in production of connected speech, but impaired ability to monitor language membership while regulating inhibitory control.


Assuntos
Doença de Alzheimer/fisiopatologia , Multilinguismo , Leitura , Distúrbios da Fala/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Feminino , Humanos , Masculino , Distúrbios da Fala/etiologia
11.
Mem Cognit ; 45(6): 956-973, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28710600

RESUMO

Three sets of experiments using the picture naming tasks with the form preparation paradigm investigated the influence of orthographic experience on the development of phonological preparation unit in spoken word production in native Mandarin-speaking children. Participants included kindergarten children who have not received formal literacy instruction, Grade 1 children who are comparatively more exposed to the alphabetic pinyin system and have very limited Chinese character knowledge, Grades 2 and 4 children who have better character knowledge and more exposure to characters, and skilled adult readers who have the most advanced character knowledge and most exposure to characters. Only Grade 1 children showed the form preparation effect in the same initial consonant condition (i.e., when a list of target words shared the initial consonant). Both Grade 4 children and adults showed the preparation effect when the initial syllable (but not tone) among target words was shared. Kindergartners and Grade 2 children only showed the preparation effect when the initial syllable including tonal information was shared. These developmental changes in phonological preparation could be interpreted as a joint function of the modification of phonological representation and attentional shift. Extensive pinyin experience encourages speakers to attend to and select onset phoneme in phonological preparation, whereas extensive character experience encourages speakers to prepare spoken words in syllables.


Assuntos
Desenvolvimento Infantil/fisiologia , Idioma , Reconhecimento Visual de Modelos/fisiologia , Psicolinguística , Fala/fisiologia , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Adulto Jovem
12.
Mem Cognit ; 45(4): 600-610, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28265900

RESUMO

Though bilinguals know many more words than monolinguals, within each language bilinguals exhibit some processing disadvantages, extending to sublexical processes specifying the sound structure of words (Gollan & Goldrick, Cognition, 125(3), 491-497, 2012). This study investigated the source of this bilingual disadvantage. Spanish-English bilinguals, Mandarin-English bilinguals, and English monolinguals repeated tongue twisters composed of English nonwords. Twister materials were made up of sound sequences that are unique to the English language (nonoverlapping) or sound sequences that are highly similar-yet phonetically distinct-in the two languages for the bilingual groups (overlapping). If bilingual disadvantages in tongue-twister production result from competition between phonetic representations in their two languages, bilinguals should have more difficulty selecting an intended target when similar sounds are activated in the overlapping sound sequences. Alternatively, if bilingual disadvantages reflect the relatively reduced frequency of use of sound sequences, bilinguals should have greater difficulty in the nonoverlapping condition (as the elements of such sound sequences are limited to a single language). Consistent with the frequency-lag account, but not the competition account, both Spanish-English and Mandarin-English bilinguals were disadvantaged in tongue-twister production only when producing twisters with nonoverlapping sound sequences. Thus, the bilingual disadvantage in tongue-twister production likely reflects reduced frequency of use of sound sequences specific to each language.


Assuntos
Multilinguismo , Psicolinguística , Fala/fisiologia , Adulto , Humanos , Adulto Jovem
13.
Microb Pathog ; 98: 57-62, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27364548

RESUMO

The serum complement system is essential for innate immune defense against invading pathogenic bacteria. Some of the 8-stranded ß-barrel outer membrane proteins confer bacterial resistance to the innate host immunity. We have previously demonstrated that OmpW, also an 8-stranded ß-barrel protein that was identified a decade ago, protects bacteria against host phagocytosis. In this study, we investigated the complement resistance of OmpW. Our results indicate that the upregulation of OmpW is associated with increased survival when bacteria are exposed to normal human sera (NHS). Mutant bacteria lacking OmpW in NHS exhibited significantly lower survival rates in comparison to wild-type and ompW complemented bacteria. Furthermore, the bacterial survival significantly decreased in NHS that was supplemented with EGTA-Mg(2+) compared to that in NHS supplemented with EDTA. These results suggest that OmpW confer resistance to alternative complement pathway-mediated killing. Moreover, the binding of OmpW to factor H, a major inhibitor of alternative pathway, was found, indicating that OmpW recruitment of factor H is a mechanism for bacterial evasion of complement attack.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Fator H do Complemento/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli/imunologia , Fatores Imunológicos/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Atividade Bactericida do Sangue , Inativadores do Complemento , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Técnicas de Inativação de Genes , Teste de Complementação Genética , Humanos , Evasão da Resposta Imune , Viabilidade Microbiana , Ligação Proteica
14.
J Theor Biol ; 389: 1-10, 2016 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-26542139

RESUMO

The mouthpart of a honeybee is a natural well-designed micropump that uses a reciprocating glossa through a temporary tube comprising a pair of galeae and labial palpi for loading nectar. The shapes and sizes of mouthparts differ among castes of honeybees, but the diversities of the functional microstructures inside the mouthparts of honeybee workers and drones remain poorly understood. Through scanning electron microscopy, we found the dimensional difference of uniformly distributed microridges on the inner galeae walls of Apis mellifera ligustica workers and drones. Subsequently, we recorded the feeding process of live honeybees by using a specially designed high-speed camera system. Considering the microridges and kinematics of the glossa, we constructed a hydrodynamic model to calculate the friction coefficient of the mouthpart. In addition, we test the drag reduction through the dimensional variations of the microridges on the inner walls of mouthparts. Theoretical estimations of the friction coefficient with respect to dipping frequency show that inner microridges can reduce friction during the feeding process of honeybees. The effects of drag reduction regulated by specific microridges were then compared. The friction coefficients of the workers and drones were found to be 0.011±0.007 (mean±s.d.) and 0.045±0.010, respectively. These results indicate that the mouthparts of workers are more capable of drag reduction compared with those of drones. The difference was analyzed by comparing the foraging behavior of the workers and drones. Workers are equipped with well-developed hypopharyngeal, and their dipping frequency is higher than that of drones. Our research establishes a critical link between microridge dimensions and drag reduction capability during the nectar feeding of honeybees. Our results reveal that microridges inside the mouthparts of honeybee workers and drones reflect the caste-related life cycles of honeybees.


Assuntos
Abelhas/anatomia & histologia , Ingestão de Alimentos/fisiologia , Boca/anatomia & histologia , Animais , Fenômenos Biomecânicos , Fricção , Hidrodinâmica , Microscopia Eletrônica de Varredura , Modelos Teóricos , Boca/ultraestrutura , Néctar de Plantas , Gravação em Vídeo
15.
J Proteome Res ; 14(10): 4309-18, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26369940

RESUMO

Protein lysine acylation, including acetylation and succinylation, has been found to be a major post-translational modification (PTM) and is associated with the regulation of cellular processes that are widespread in bacteria. Vibrio parahemolyticus is a model marine bacterium that causes seafood-borne illness in humans worldwide. The lysine acetylation of V. parahemolyticus has been extensively characterized in our previous work, and here, we report the first global analysis of lysine succinylation and the overlap between the two types of acylation in this bacterium. Using high-accuracy nano liquid chromatography-tandem mass spectrometry combined with affinity purification, we identified 1931 lysine succinylated peptides matched on 642 proteins, with the quantity of the succinyl-proteins accounting for 13.3% of the total proteins in cells. Bioinformatics analysis results showed that these succinylated proteins are involved in almost every cellular process, particularly in protein biosynthesis and metabolism, and are distributed in diverse subcellular compartments. Moreover, several sequence motifs were identified, including succinyl-lysine flanked by a lysine or arginine residue at the -8, -7, or +7 position and without these residues at the -1 or +2 position, and these motifs differ from those found in other bacteria and eukaryotic cells. Furthermore, a total of 517 succinyl-lysine sites (26.7%) on 288 proteins (44.9%) were also found to be acetylated, suggesting extensive overlap between succinylation and acetylation in this bacterium. This systematic analysis provides a promising starting point for further investigations of the physiologic and pathogenic roles of lysine succinylation and acetylation in V. parahemolyticus.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Lisina/metabolismo , Processamento de Proteína Pós-Traducional , Proteoma/isolamento & purificação , Ácido Succínico/metabolismo , Vibrio parahaemolyticus/metabolismo , Acetilação , Motivos de Aminoácidos , Organismos Aquáticos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cromatografia Líquida , Lisina/química , Anotação de Sequência Molecular , Dados de Sequência Molecular , Biossíntese de Proteínas , Proteoma/genética , Proteoma/metabolismo , Ácido Succínico/química , Espectrometria de Massas em Tandem , Vibrio parahaemolyticus/química , Vibrio parahaemolyticus/genética
16.
Mem Cognit ; 43(4): 563-78, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25398357

RESUMO

Two experiments using the form-preparation paradigm were conducted to investigate the effect of orthographic form-cuing on the phonological preparation unit during spoken word production with native Mandarin speakers. In both experiments, participants were instructed to memorize nine prompt-response monosyllabic word pairs, after which an associative naming session was conducted in which the prompts were presented and participants were asked to say the corresponding response names as quickly and accurately as possible. In both experiments, the response words in the homogeneous lists shared the same onsets, or shared the same rimes; the response names had no common aspects of pronunciation in the heterogeneous lists. Chinese characters (Experiment 1) and Pinyin (phonetic transcription of the characters) (Experiment 2) were used to investigate the effect of the orthographic form. Significant onset facilitation and rime inhibition was shown for Pinyin syllables but not for characters. The contrasts of the onset and rime effect in the two orthographic forms suggest that a specific phonological unit is promoted in spoken word production in a certain orthographic form. Pinyin cued the participants to prepare the onset whereas Chinese characters did not. The rime interference effect may arise as a result of lexical competition in spoken word production.


Assuntos
Reconhecimento Visual de Modelos/fisiologia , Leitura , Fala/fisiologia , Adulto , Sinais (Psicologia) , Feminino , Humanos , Masculino , Adulto Jovem
17.
Artigo em Inglês | MEDLINE | ID: mdl-39120984

RESUMO

Novel drug-target interaction (DTI) prediction is crucial in drug discovery and repositioning. Recently, graph neural network (GNN) has shown promising results in identifying DTI by using thresholds to construct heterogeneous graphs. However, an empirically selected threshold can lead to loss of valuable information, especially in sparse networks, a common scenario in DTI prediction. To make full use of insufficient information, we propose a DTI prediction model based on Dynamic Heterogeneous Graph (DT-DHG). And progressive learning is introduced to adjust the receptive fields of node. The experimental results show that our method significantly improves the performance of the original GNNs and is robust against the choices of backbones. Meanwhile, DT-DHG outperforms the state-of-the-art methods and effectively predicts novel DTIs. The source code is available at https://github.com/kissablemt/DT-DHG.

18.
Chem Commun (Camb) ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39400031

RESUMO

A fluorescence method has been successfully constructed to accurately measure the D/L-Arb configuration content in optical isomers, and its application in ion detection has been expanded, which has greater sensitivity and universality than the circular dichroism (CD) method. It also promotes the study of the emission mechanism of nonconventional luminogens.

19.
Acta Biomater ; 186: 330-341, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39097128

RESUMO

Most of the plants using epizoochory show adaptations to this diaspore dispersal strategy by having the diaspores covered by barbs, hooks, spines or viscid outgrowths, which allow diaspores to easily attach to an animal surface. Many previous studies have been mainly focused on the dispersal distances and efficiency, or effectiveness of diverse attachment structures depending on their size, anatomy, and morphology. However, the knowledge about the mechanical properties of these structures remains rather poor. In this study, we use a combination of scanning electron microscopy, energy dispersive X-ray element analysis and nanoindentation, to examine the microstructure, biomineralization and mechanical properties of single hooks in Arctium minus, Cynoglossum officinale and Galium aparine. Both the biomineralization and mechanical properties of the hooks strongly differ in examined plant species; mechanical properties depend on the biomineralization pattern, such as the accumulation of silicon and calcium. Elastic modulus and hardness decrease in the series C. officinaleG. aparineA. minus. Anisotropic mechanical properties are found between the radial and longitudinal directions in each single hook. By characterizing the mechanical properties and biomineralization of plant hooks, this paper contributes to the understanding of attachment biomechanics related to seed dispersal. STATEMENT OF SIGNIFICANCE: The dispersal of seeds is essential for plant survival. Many of the plants that use the outside surface of animals to transport the seeds show adaptations to this dispersal strategy by having the seeds covered with hooks. Although these hooks have various sizes, morphologies and anatomical structures, all of them provide mechanical interlocking to animal surfaces. To reduce the risk of interlocking failure, the hooks are usually reinforced by mineralization. However, the relationship between mineralization, mechanical properties and specialized function of plant hooks has been largely overlooked. Here we perform a characterization study on the hooks of three plant species. Our results deepen the current understanding of the mineralization-material-function relationship in specialized hooks of plant seeds.


Assuntos
Biomineralização , Biomineralização/fisiologia , Especificidade da Espécie , Módulo de Elasticidade , Fenômenos Biomecânicos
20.
Front Genet ; 15: 1388015, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737125

RESUMO

LncRNAs are an essential type of non-coding RNAs, which have been reported to be involved in various human pathological conditions. Increasing evidence suggests that drugs can regulate lncRNAs expression, which makes it possible to develop lncRNAs as therapeutic targets. Thus, developing in-silico methods to predict lncRNA-drug associations (LDAs) is a critical step for developing lncRNA-based therapies. In this study, we predict LDAs by using graph convolutional networks (GCN) and graph attention networks (GAT) based on lncRNA and drug similarity networks. Results show that our proposed method achieves good performance (average AUCs > 0.92) on five datasets. In addition, case studies and KEGG functional enrichment analysis further prove that the model can effectively identify novel LDAs. On the whole, this study provides a deep learning-based framework for predicting novel LDAs, which will accelerate the lncRNA-targeted drug development process.

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