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1.
Cereb Cortex ; 33(6): 2931-2946, 2023 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35739457

RESUMEN

The brain's response to change is fundamental to learning and adaptation; this implies the presence of a universal neural mechanism under various contexts. We hypothesized that this mechanism manifests in neural activity patterns across low and high levels of cognition during task processing as well as in resting-state neural dynamics, because both these elements are different facets of the same dynamical system. We tested our hypothesis by (i) characterizing (a) the neural response to changes in low-level continuous information stream and unexpectedness at different cognitive levels and (b) the spontaneous neural dynamics in resting state, and (ii) examining the associations among the dynamics according to cross-individual variability (n = 200). Our results showed that the brain's response magnitude was monotonically correlated with the magnitude of information fluctuation in a low-level task, forming a simple psychophysical function; moreover, this effect was found to be associated with the brain's response to unexpectedness in high-level cognitive tasks (including language processing). These coherent multilevel neural effects in task processing were also shown to be strongly associated with resting-state neural dynamics characterized by the waxing and waning of Alpha oscillation. Taken together, our results revealed large-scale consistency between the neural dynamic system and multilevel cognition.


Asunto(s)
Mapeo Encefálico , Encéfalo , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Mapeo Encefálico/métodos , Cognición/fisiología , Vías Nerviosas/fisiología , Aprendizaje , Imagen por Resonancia Magnética , Descanso/fisiología
2.
Inorg Chem ; 62(18): 6934-6947, 2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37098153

RESUMEN

Several isostructural lanthanide metal-organic frameworks, viz. [Ln(DCHB)1.5phen]n (Ln-MOFs, where Ln = Eu for 1, Tb for 2, Sm for 3 and Dy for 4), are successfully synthesized through the hydrothermal reactions of 4'-di(4-carboxylphenoxy)hydroxyl-2, 2'-bipyridyl (H2DCHB) and lanthanide nitrates as well as chelator 1,10-phenantroline (phen). These structures are characterized by single-crystal X-ray diffraction, and the representative Ln-MOF 1 is a fivefold interpenetrated framework with the uncoordinated Lewis base N sites form DCHB2- ligands. The photoluminescence research studies reveal that Ln-MOFs 1-4 exhibit characteristic fluorescent emissions from ligand-induced lanthanide Ln(III) ions, while the single-component emission spectra of Ln-MOF 4 are all located in a white region under different excitations. The absence of coordinated water and the interpenetration property of the structures are conducive to the structure rigidity, and the results display that Ln-MOF 1 has high thermal/chemical stabilities in common solvents and a wide pH range as well as the boiling water. Notably, luminescent sensing studies reveal that Ln-MOF 1 with prominent fluorescence properties can perform in highly sensitive and selective sensing of vanillylmandelic acid (VMA) in aqueous systems (KSV = 562.8 L·mol-1; LOD = 4.6 × 10-4 M), which can potentially establish a detection platform for the diagnosis of pheochromocytoma via multiquenching mechanisms. Moreover, the 1@MMMs sensing membranes comprised of Ln-MOF 1 and a poly(vinylidene fluoride) (PVDF) polymer can also be facilely developed for VMA detection in aqueous media, suggesting the enhanced convenience and efficiency of practical sensing applications.

3.
Pestic Biochem Physiol ; 195: 105535, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37666588

RESUMEN

Entomopathogenic fungi are a promising category of biocontrol agents with mosquitocidal properties. Prior studies have proved their potential to reduce fecundity, human biting and vector competence, all of them together determine vectorial capacity of the mosquitoes. Unfortunately, conventional vector control strategies are inadequate with growing problem of insecticide resistance and environmental deterioration. Therefore, alternate vector control measures are immediately needed and to accomplish that, an improved understanding of behavioral and physiological defense mechanisms of the mosquitoes against fungal infection is essential. In this study, fitness was considered with respect to different behavioral (self-grooming and flight), physiological (antifungal activity and antimicrobial peptides) parameters and survival rates as compared to the control group. We found a significant upregulation in CLSP2, TEP22, Rel1 and Rel2 genes at multiple time periods of fungal infection, which indicates the successful fungal infection and activation of Toll and IMD pathways in mosquitoes. RNAi-mediated silencing of Rel1 and Rel2 genes (transcription factors of Toll and IMD pathways, respectively) significantly reduced the survival, self-grooming frequencies and durations, and flight locomotor activity among adult Ae. aegypti female mosquitoes. Moreover, Rel1 and Rel2 knockdown significantly decreased antifungal activity and antimicrobial peptides expression levels in target mosquitoes. These results indicate an overall decrease in fitness of the mosquitoes after fungal challenge following Rel1 and Rel2 silencing. These findings provide an improved understanding of behavioral and physiological responses in mosquitoes with altered immunity against entomopathogenic fungal infections which can guide us towards the development of novel biocontrol strategies against mosquitoes.


Asunto(s)
Aedes , Micosis , Animales , Humanos , Aedes/genética , Antifúngicos , Mosquitos Vectores/genética , Silenciador del Gen , Péptidos Antimicrobianos
4.
Anal Bioanal Chem ; 414(11): 3359-3372, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35166866

RESUMEN

The traditional manual analysis of microplastics has been criticized for its labor-intensive, inaccurate identification of small microplastics, and the lack of uniformity. There are already three automated analysis strategies for microplastics based on vibrational spectroscopy: laser direct infrared (LDIR)-based particle analysis, Raman-based particle analysis, and focal plane array-Fourier transform infrared (FPA-FTIR) imaging. We compared their performances in terms of quantification, detection limit, size measurement, and material identification accuracy and speed by analyzing the same standard and environmental samples. LDIR-based particle analysis provides the fastest analysis speed, but potentially questionable material identification and quantification results. The number of particles smaller than 60 µm recognized by LDIR-based particle analysis is much less than that recognized by Raman-based particle analysis. Misidentification could occur due to the narrow tuning range from 1800 to 975 cm-1 and dispersive artifact distortion of infrared spectra collected in reflection mode. Raman-based particle analysis has a submicrometer detection limit but should be cautiously used in the automated analysis of microplastics in environmental samples because of the strong fluorescence interference. FPA-FTIR imaging provides relatively reliable quantification and material identification for microplastics in environmental samples greater than 20 µm but might provide an imprecise description of the particle shapes. Optical photothermal infrared (O-PTIR) spectroscopy can detect submicron-sized environmental microplastics (0.5-5 µm) intermingled with a substantial amount of biological matrix; the resulting spectra are searchable in infrared databases without the influence of fluorescence interference, but the process would need to be fully automated.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Benchmarking , Monitoreo del Ambiente/métodos , Plásticos , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/análisis
5.
Neuroimage ; 244: 118578, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34534659

RESUMEN

How do the temporal dynamics of neural activity encode highly coordinated visual-motor behaviour? To capture the millisecond-resolved neural activations associated with fine visual-motor skills, we devised a co-registration system to simultaneously record electroencephalogram and handwriting kinematics while participants were performing four handwriting tasks (writing in Chinese/English scripts with their dominant/non-dominant hand). The neural activation associated with each stroke was clearly identified with a well-structured and reliable pattern. The functional significance of this pattern was validated by its significant associations with language, hand and the cognitive stages and kinematics of handwriting. Furthermore, the handwriting rhythmicity was found to be synchronised to the brain's ongoing theta oscillation, and the synchronisation was associated with the factor of language and hand. These major findings imply an implication between motor skill formation and the interplay between the rhythms in the brain and the peripheral systems.


Asunto(s)
Escritura Manual , Destreza Motora/fisiología , Adulto , Pueblo Asiatico , Fenómenos Biomecánicos , Encéfalo/fisiología , Electroencefalografía , Femenino , Mano , Hong Kong , Humanos , Lenguaje , Masculino , Factores de Tiempo
6.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4089-4095, 2021 Aug.
Artículo en Zh | MEDLINE | ID: mdl-34467718

RESUMEN

Gastric cancer(GC), one of the most common malignancies worldwide, seriously threatens human health due to its high morbidity and mortality. Precancerous lesion of gastric cancer(PLGC) is a critical stage for preventing the occurrence of gastric cancer, and PLGC therapy has frequently been investigated in clinical research. Exploring the proper animal modeling methods is necessary since animal experiment acts as the main avenue of the research on GC treatment. At present, N-methyl-N'-nitro-N-nitroso-guanidine(MNNG) serves as a common chemical inducer for the rat model of GC and PLGC. In this study, MNNG-based methods for modeling PLGC rats in related papers were summarized, and the applications and effects of these methods were demonstrated by examples. Additionally, the advantages, disadvantages, and precautions of various modeling methods were briefly reviewed, and the experience of this research group in exploring modeling methods was shared. This study is expected to provide a reference for the establishment of MNNG-induced PLGC animal model, and a model support for the following studies on PLGC.


Asunto(s)
Lesiones Precancerosas , Neoplasias Gástricas , Animales , Mucosa Gástrica , Metilnitronitrosoguanidina/toxicidad , Lesiones Precancerosas/inducido químicamente , Ratas , Neoplasias Gástricas/inducido químicamente , Neoplasias Gástricas/tratamiento farmacológico
7.
Neuroimage ; 205: 116304, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31654760

RESUMEN

Research in cognitive neuroscience has extensively demonstrated that the temporal dynamics of brain activity are associated with cognitive functioning. The temporal dynamics mainly include oscillatory and 1/f noise-like, non-oscillatory brain activities that coexist in many forms of brain activity and confound each other's variability. As such, observed functional associations of narrowband oscillations might have been confounded with the broadband 1/f component. Here, we investigated the relationship between resting-state EEG activity and the efficiency of cognitive functioning in N = 180 individuals. We show that 1/f brain activity plays an essential role in accounting for between-person variability in cognitive speed - a relationship that can be mistaken as originating from brain oscillations using conventional power spectrum analysis. At first glance, the power of alpha oscillations appeared to be predictive of cognitive speed. However, when dissociating pure alpha oscillations from 1/f brain activity, only the 1/f predicted cognitive speed, whereas the predictive power of alpha vanished. With this highly powered study, we disambiguate the functional relevance of the 1/f power law pattern in resting state neural activities and substantiate the necessity of isolating the 1/f component from oscillatory activities when studying the functional relevance of spontaneous brain activities.


Asunto(s)
Ritmo alfa/fisiología , Corteza Cerebral/fisiología , Electroencefalografía , Neuroimagen Funcional , Red Nerviosa/fisiología , Reconocimiento Visual de Modelos/fisiología , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Reconocimiento en Psicología/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Adulto Joven
8.
Int J Hyperthermia ; 37(1): 399-403, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32345115

RESUMEN

Objective: To evaluate the impact of ultrasound-guided high-intensity focused ultrasound (USgHIFU) for uterine fibroids on ovarian reserve in women of reproductive age.Materials and methods: From September 2015 to September 2017, 84 patients with uterine fibroids in reproductive age were enrolled from Chongqing Haifu Hospital, Three Gorges Central Hospital of Chongqing and Aegisroen obstetric gynecology Clinic of Seoul, Korea. Blood was collected before HIFU treatment and 6 months after USgHIFU treatment. The enzyme-linked immune analysis was used for assay of circulating anti-Mullerian hormone (AMH).Results: All the 84 patients were successfully treated with USgHIFU and 67 patients completed the follow-up. The median age of the 67 patients was 38 years at the time of treatment. The median AMH value before and 6 months after treatment was 1.26 ng/mL and 1.27 ng/mL, respectively. Patients who completed AMH measurements 6 months after treatment were further classified into three groups based on age, including younger than 35 years, 36 to 40 years, and older than 40 years. The median AMH values before treatment were 3.04 ng/mL, 1.73 ng/mL and 0.87 ng/mL, and the corresponding values 6 months after treatment were 3.24, 1.44 and 0.75, respectively. A significant difference in AMH level was observed in the group of patients at the age between 36 and 40 years (p < 0.05), but no significant difference in AMH levels was observed in the other two groups (p > 0.05).Conclusion: Based on our results, we conclude that USgHIFU has no influence on ovarian reserve.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Leiomioma/terapia , Reserva Ovárica/fisiología , Adulto , Femenino , Humanos , Leiomioma/diagnóstico por imagen
9.
Phys Rev Lett ; 116(1): 018101, 2016 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-26799044

RESUMEN

Self-organized critical states (SOCs) and stochastic oscillations (SOs) are simultaneously observed in neural systems, which appears to be theoretically contradictory since SOCs are characterized by scale-free avalanche sizes but oscillations indicate typical scales. Here, we show that SOs can emerge in SOCs of small size systems due to temporal correlation between large avalanches at the finite-size cutoff, resulting from the accumulation-release process in SOCs. In contrast, the critical branching process without accumulation-release dynamics cannot exhibit oscillations. The reconciliation of SOCs and SOs is demonstrated both in the sandpile model and robustly in biologically plausible neuronal networks. The oscillations can be suppressed if external inputs eliminate the prominent slow accumulation process, providing a potential explanation of the widely studied Berger effect or event-related desynchronization in neural response. The features of neural oscillations and suppression are confirmed during task processing in monkey eye-movement experiments. Our results suggest that finite-size, columnar neural circuits may play an important role in generating neural oscillations around the critical states, potentially enabling functional advantages of both SOCs and oscillations for sensitive response to transient stimuli.


Asunto(s)
Encéfalo/fisiología , Modelos Neurológicos , Red Nerviosa/fisiología , Neuronas/fisiología , Relojes Biológicos , Humanos , Procesos Estocásticos
10.
Brain Topogr ; 29(6): 791-813, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27509898

RESUMEN

Overt articulation produces strong artifacts in the electroencephalogram and in event-related potentials (ERPs), posing a serious problem for investigating language production with these variables. Here we describe the properties of articulation-related artifacts and propose a novel correction procedure. Experiment 1 co-recorded ERPs and trajectories of the articulators with an electromagnetic articulograph from a single participant. The generalization of the findings from the single participant to standard picture naming was investigated in Experiment 2. Both experiments provided evidence that articulation-induced artifacts may start up to 300 ms or more prior to voice onset or voice key onset-depending on the specific measure; they are highly similar in topography across many different phoneme patterns and differ mainly in their time course and amplitude. ERPs were separated from articulation-related artifacts with residue iteration decomposition (RIDE). After obtaining the artifact-free ERPs, their correlations with the articulatory trajectories dropped near to zero. Artifact removal with independent component analysis was less successful; while correlations with the articulatory movements remained substantial, early components prior to voice onset were attenuated in reconstructed ERPs. These findings offer new insights into the nature of articulation artifacts; together with RIDE as method for artifact removal the present report offers a fresh perspective for ERP studies requiring overt articulation.


Asunto(s)
Artefactos , Encéfalo/fisiología , Potenciales Evocados/fisiología , Lenguaje , Movimiento , Habla , Adolescente , Adulto , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Voz , Adulto Joven
11.
Brain Topogr ; 29(1): 82-93, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26012382

RESUMEN

The late positive potential (LPP) elicited by affective stimuli in the event-related brain potential (ERP) is often assumed to be a member of the P3 family. The present study addresses the relationship of the LPP to the classic P3b in a published data set, using a non-parametric permutation test for topographical comparisons, and residue iteration decomposition to assess the temporal features of the LPP and the P3b by decomposing the ERP into several component clusters according to their latency variability. The experiment orthogonally manipulated arousal and valence of words, which were either read or judged for lexicality. High-arousing and positive valenced words induced a larger LPP than low-arousing and negative valenced words, respectively, and the LDT elicited a larger P3b than reading. The experimental manipulation of arousal, valence, and task yielded main effects without any interactions on ERP amplitude in the LPP/P3b time range. The arousal and valence effects partially differed from the task effect in scalp topography; in addition, whereas the late positive component elicited by affective stimuli, defined as LPP, was stimulus-locked, the late positive component elicited by task demand, defined as P3b, was mainly latency-variable. Therefore LPP and P3b manifest different subcomponents.


Asunto(s)
Nivel de Alerta/fisiología , Mapeo Encefálico , Encéfalo/fisiología , Cognición/fisiología , Emociones/fisiología , Vocabulario , Adulto , Electroencefalografía , Femenino , Humanos , Masculino , Estimulación Luminosa , Adulto Joven
12.
Molecules ; 21(4): 516, 2016 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-27104509

RESUMEN

A series of novel 5-hydrosulfonyl-1H-benzo[d]imidazol-2(3H)-one derivatives bearing natural product substructures has been successfully synthesized and their antitumor activity studied. These newly synthesized derivatives were characterized by ¹H-NMR, (13)C-NMR and high resolution mass spectral data, then screened as antitumor agents against the A549, HCC1937, and MDA-MB-468 human tumor cell lines using MTT cell proliferation assays. The results show that some of these compounds can effectively inhibit the growth of these cancerous cells, with compound 5b being the best one (IC50 = 2.6 µM). Flow cytometry data revealed that compound 5b induced apoptosis of HCC1937 cells with increased solution concentration. The structure and activity relationships (SAR) of these compounds is summarized.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Bencimidazoles/síntesis química , Bencimidazoles/farmacología , Antineoplásicos/química , Apoptosis , Bencimidazoles/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad
13.
Angew Chem Int Ed Engl ; 54(14): 4334-7, 2015 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-25677923

RESUMEN

An aza-crown ether, modified phosphoramidite ligand, has been designed and synthesized. The ON/OFF reversible switch of catalytic activity for its rhodium catalyst was thoroughly investigated in the asymmetric hydrogenation of dehydroamino acid esters modulated by host-guest interactions. In the OFF state, the catalyst is almost inactive (less than 1% conversion) because of the formation of an intermolecular sandwich complex by two aza-crown ether moities and the cationic rhodium metal center. In using alkali-metal-cations as the trigger, the catalytic activity was turned ON and consequently resulted in full conversions and excellent enantioselectivities (up to 98% ee).

14.
Neuroimage ; 100: 271-80, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-24960419

RESUMEN

It has been proposed that the P3b component of event-related potentials (ERPs) reflects linking of responses to target stimuli. This proposal was tested by disconnecting the temporal link between target stimuli and responses, and by applying residue iteration decomposition (RIDE) for separating the ERP components into stimulus-locked, response-locked, and "intermediate" clusters. Left or right keys had to be pressed in response to frequent (80%) and rare (20%) target letters, but responses had to wait for "go" signals (appearing in 90% of trials). Between blocks, stimulus-onset asynchronies (SOAs) from targets to go-signals varied from 0 ms to 800 ms. Rare targets with their rare responses were expected to evoke large P3bs ("oddball effect"). If related to stimulus processing only, this effect will be equally large across all SOAs and will be modeled by RIDE's stimulus-cluster. If related to response initiation only, the oddball effect will be evoked by go-signals rather than by targets and will be modeled by RIDE's response-cluster. If indicating integration of rare stimuli with their rare responses, the oddball effect will be evoked by targets but will be reduced and stretched in time across SOAs and will be modeled by RIDE's intermediate cluster. RIDE analysis confirmed this latter view, for the most part. SOA effects matched best, though not perfectly, predictions made by the stimulus-response-link view. These results call for a refined account of the oddball effect on P3b in terms of stimulus-response coupling.


Asunto(s)
Corteza Cerebral/fisiología , Electroencefalografía/métodos , Potenciales Relacionados con Evento P300/fisiología , Desempeño Psicomotor/fisiología , Procesamiento de Señales Asistido por Computador , Adulto , Femenino , Humanos , Masculino , Factores de Tiempo , Adulto Joven
15.
Chemistry ; 20(50): 16454-7, 2014 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-25346533

RESUMEN

A new kind of podand-based dimeric salen ligand was synthesized, and its association with potassium cations was investigated by (1) H NMR spectroscopy. The corresponding Cr(III) -salen dimer was assembled by a supramolecular host-guest self-assembly process and was then used as a catalyst in highly efficient and enantioselective asymmetric Henry reactions. Regulation by KBArF (BArF =[3,5-(CF3 )2 C6 H3 ]4 B) led to remarkable improvements in yield (by up to 58 %) and enantioselectivity (for example, from 80 % ee to 96 % ee).

16.
Front Psychol ; 15: 1320675, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38384355

RESUMEN

This study aims to examine the process of L2 novel word learning through the combination of episodic and semantic memory, and how the process differs between the formation of thematic and taxonomic relations. The major approach adopted was observing the neural effects of word learning, which is manifested in the N400 from event-related potentials (ERPs). Eighty-eight participants were recruited for the experiment. In the learning session, L2 contextual discourses related to novel words were learned by participants. In the testing session, discourses embedded with incongruous and congruous novel words in the final position were used for participants to judge the congruency which affected the N400 neural activity. The results showed that both recurrent and new-theme discourses elicited significant N400 effects, while taxonomic sentences did not. These results confirmed the formation of episodic and semantic memory during L2 new word learning, in which semantic memory was mainly supported by thematic relations.

17.
World J Clin Cases ; 12(11): 1940-1946, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38660547

RESUMEN

BACKGROUND: Direct carotid cavernous fistulas (CCFs) are typically the result of a severe traumatic brain injury. High-flow arteriovenous shunts secondary to rupture of an intracavernous aneurysm, resulting in direct CCFs, are rare. The use of a pipeline embolization device in conjunction with coils and Onyx glue for treatment of direct high-flow CCF resulting from ruptured cavernous carotid artery aneurysm in a clinical setting is not well documented. CASE SUMMARY: A 58-year-old woman presented to our department with symptoms of blepharoptosis and intracranial bruits for 1 wk. During physical examination, there was right eye exophthalmos and ocular motor palsy. The rest of the neurological examination was clear. Notably, the patient had no history of head injury. The patient was treated with a pipeline embolization device in the ipsilateral internal carotid artery across the fistula. Coils and Onyx were placed through the femoral venous route, followed by placement of the pipeline embolization device with assistance from a balloon-coiling technique. No intraoperative or perioperative complications occurred. Preoperative symptoms of bulbar hyperemia and bruits subsided immediately after the operation. CONCLUSION: Pipeline embolization device in conjunction with coiling and Onyx may be a safe and effective approach for direct CCFs.

18.
Environ Sci Pollut Res Int ; 31(21): 30793-30805, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38613759

RESUMEN

Excessive use of synthetic insecticides has resulted in environmental contamination and adverse effects on humans and other non-target organisms. Entomopathogenic fungi offer eco-friendly alternatives; however, their application for pest control requires significant advancement owing to limitations like slow killing time and effectiveness only when applied in higher amounts, whereas exposure to UV radiation, high temperature, and humidity can also reduce their viability and shelf-life. The nanoparticles synthesized using fungal extracellular extracts provide a new approach to use fungal pathogens. Our study focused on the synthesis of Metarhizium anisopliae-based silver nanoparticles (AgNPs) and evaluation of their efficiency on various physiological and behavioral parameters of the mosquito Aedes aegypti. The synthesis, size (27.6 d.nm, PDI = 0.209), zeta potential (- 24.3 mV), and shape of the AgNPs were determined through dynamic light scattering, scanning and transmission electron microscopic, and UV-visual spectroscopic analyses (432 nm). Our results showed significantly reduced survival (100% decrease in case of 3.2 and 1.8 µL/cm2 volumes, and 60% decrease in case of 0.8 µL/cm2 volume), phenoloxidase activity (t = 39.91; p = 0.0001), and gut microbiota, with increased oxidative stress and cell apoptosis in AgNPs-challenged mosquitoes. Furthermore, the AgNPs-exposed mosquitoes presented a concentration-specific decrease in flight locomotor activity (F = 17.312; p < 0.0001), whereas no significant changes in antifungal activity, self-grooming frequencies, or time spent were found. These findings enhance our understanding of mosquito responses to AgNPs exposure, and offer a more efficient mosquito control strategy using entomopathogenic fungi.


Asunto(s)
Aedes , Insecticidas , Nanopartículas del Metal , Plata , Animales , Aedes/efectos de los fármacos , Plata/química , Plata/farmacología , Nanopartículas del Metal/química , Insecticidas/química , Metarhizium , Control de Mosquitos/métodos , Hongos
19.
Molecules ; 18(5): 5142-54, 2013 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-23644979

RESUMEN

An efficient synthesis of novel dispirooxindoles has been achieved through three-component 1,3-dipolar cycloaddition of azomethine ylides generated in situ by the decarboxylative condensation of isatin and an α-amino acid with the dipolarophile 5-benzylideneimidazolidine-2,4-dione. The improved procedure features mild reaction conditions, high yields, high diastereoselectivities, a one-pot procedure and operational simplicity.


Asunto(s)
Compuestos Azo/química , Compuestos Heterocíclicos con 1 Anillo/química , Compuestos Heterocíclicos con 1 Anillo/síntesis química , Isatina/química , Tiosemicarbazonas/química , Estructura Molecular
20.
Bioengineering (Basel) ; 10(9)2023 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-37760156

RESUMEN

Characterizing the brain's dynamic pattern of response to an input in electroencephalography (EEG) is not a trivial task due to the entanglement of the complex spontaneous brain activity. In this context, the brain's response can be defined as (1) the additional neural activity components generated after the input or (2) the changes in the ongoing spontaneous activities induced by the input. Moreover, the response can be manifested in multiple features. Three commonly studied examples of features are (1) transient temporal waveform, (2) time-frequency representation, and (3) phase dynamics. The most extensively used method of average event-related potentials (ERPs) captures the first one, while the latter two and other more complex features are attracting increasing attention. However, there has not been much work providing a systematic illustration and guidance for how to effectively exploit multifaceted features in neural cognitive research. Based on a visual oddball ERPs dataset with 200 participants, this work demonstrates how the information from the above-mentioned features are complementary to each other and how they can be integrated based on stereotypical neural-network-based machine learning approaches to better exploit neural dynamic information in basic and applied cognitive research.

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