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1.
J Econ Entomol ; 116(4): 1276-1285, 2023 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-37279557

RESUMEN

The whitefly, Bemisia tabaci, is a destructive and invasive pest of many horticultural plants including poinsettia (Euphorbia pulcherrima). Outbreaks of B. tabaci cause serious damage by direct feeding on phloem sap, and spreading 100+ plant viruses to crops. Bemisia tabaci were observed more frequently on green than red poinsettia leaves, and the factors responsible for this are unknown. Here, we investigated the development rate, survivorship, fecundity of B. tabaci feeding on green versus red leaves, as well as the leaves' volatiles, trichome density, anthocyanin content, soluble sugars, and free amino acids. Compared to red leaves, B. tabaci on green leaves showed increased fecundity, a higher female sex ratio, and survival rate. The green color alone was more attractive to B. tabaci than red. Red leaves of poinsettia contained more phenol, and panaginsene in their volatiles. Alpha-copaene and caryophyllene were more abundant in the volatiles of poinsettia green leaves. Leaf trichome density, soluble sugars and free amino acids were higher in green than red leaves of poinsettia, anthocyanin was lower in green than red leaves. Overall, green leaves of poinsettia were more susceptible and attractive to B. tabaci. The morphological and chemical variation between red and green leaves also differed; further investigation may reveal how these traits affect B. tabaci's responses.


Asunto(s)
Euphorbia , Hemípteros , Animales , Aminoácidos/análisis , Antocianinas/análisis , Hojas de la Planta/química , Tricomas , Masculino , Femenino
2.
Int J Biol Macromol ; 236: 123928, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36889622

RESUMEN

The control region (CR) of the mitochondrial genome (mitogenome) represents a major noncoding fragment with several special structural features that are thought to be responsible for the initiation of mitogenome transcription and replication. However, few studies have revealed the evolutionary patterns of CR in the phylogenetic context. Here, we explain the characteristics and evolution of CR in Tortricidae, inferred from a mitogenome-based phylogeny. The first complete mitogenomes of the genera Meiligma and Matsumuraeses were sequenced. Both mitogenomes are double-stranded circular DNA molecules with lengths of 15,675 bp and 15,330 bp, respectively. Phylogenetic analyses derived from 13 protein-coding genes and two ribosomal RNAs showed that most tribes, including subfamilies Olethreutinae and Tortricinae, were recovered as monophyletic clades, similar to previous studies based on morphological or nuclear data. Moreover, comprehensive comparative analyses of the structural organization and role of tandem replications on the length variation and high AT content of CR sequences were conducted. The results reveal a significant positive correlation between the total length and AT content of tandem repeats and whole CR sequences in Tortricidae. The structural organization in CR sequences is diverse, even between closely related tribes, which demonstrates the plasticity of the mitochondrial DNA molecule in Tortricidae.


Asunto(s)
Genoma Mitocondrial , Lepidópteros , Mariposas Nocturnas , Animales , Mariposas Nocturnas/genética , Lepidópteros/genética , Genoma Mitocondrial/genética , Filogenia , ADN Mitocondrial/genética , ARN Ribosómico/genética , ARN de Transferencia/genética
3.
J Biophotonics ; 16(6): e202200369, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36808258

RESUMEN

Normalized mutual information (NMI) can be used to detect statistical correlations between time series. We showed possibility of using NMI to quantify synchronicity of information transmission in different brain regions, thus to characterize functional connections, and ultimately analyze differences in physiological states of brain. Resting-state brain signals were recorded from bilateral temporal lobes by functional near-infrared spectroscopy (fNIRS) in 19 young healthy (YH) adults, 25 children with autism spectrum disorder (ASD), and 22 children with typical development (TD). Using NMI of the fNIRS signals, common information volume was assessed for each of three groups. Results showed that mutual information of children with ASD was significantly smaller than that of TD children, while mutual information of YH adults was slightly larger than that of TD children. This study may suggest that NMI could be a measure for assessing brain activity with different development states.


Asunto(s)
Trastorno del Espectro Autista , Niño , Adulto , Humanos , Trastorno del Espectro Autista/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Análisis Espectral , Factores de Tiempo
4.
J Neurosci Methods ; 383: 109732, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36349567

RESUMEN

BACKGROUND: The demand for early and precise identification of autism spectrum disorder (ASD) presented a challenge to the prediction of ASD with a non-invasive neuroimaging method. NEW METHOD: A deep learning model was proposed to identify children with ASD using the resting-state functional near-infrared spectroscopy (fNIRS) signals. In this model, the input was the pattern of brain complexity represented by multiscale entropy of fNIRS time-series signals, with the purpose to solve the problem of deep learning analysis when the raw signals were limited by length and the number of subjects. The model consisted of a two-branch deep learning network, where one branch was a convolution neural network and the other was a long short-term memory neural network based on an attention mechanism. RESULTS: Our model could achieve an identification accuracy of 94%. Further analysis used the SHapley Additive exPlanations (SHAP) method to balance the accuracy and the number of optical channels, thus reducing the complexity of fNIRS experiment. COMPARISON WITH PREVIOUSLY USED METHOD(S): in identification accuracy, our model was about 14% higher than previously used deep learning models with the same input and 4% higher than the same model but directly using fNIRS signals as input. We could obtain a discriminative accuracy of 90% with nearly half of the measurement channels by the SHAP method. CONCLUSIONS: Using the pattern of brain complexity as input was effective in the deep learning model when the fNIRS signals were insufficient. With the SHAP method, it was possible to reduce the number of optical channels, while maintaining high accuracy in ASD identification.


Asunto(s)
Trastorno del Espectro Autista , Aprendizaje Profundo , Niño , Humanos , Trastorno del Espectro Autista/diagnóstico por imagen , Entropía , Espectroscopía Infrarroja Corta/métodos , Encéfalo/diagnóstico por imagen
5.
Head Neck ; 45(1): 126-134, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36222335

RESUMEN

BACKGROUND: The immune profile in primary resected hypopharyngeal squamous cell carcinoma (HPSCC) and its prognostic value remain to be defined. METHODS: We enrolled 100 patients with HPSCC underwent primary surgical resection at our department. HPSCC samples were examined using immunohistochemistry for the expressions of CD8, Foxp3, CD163, CD66B, programmed death ligand-1 (PD-L1), and interferon (IFN)-γ. The immune pattern of the tumor microenvironment (TME) was discriminated into inflamed and non-inflamed tumors based on the presence or absence of parenchymal CD8+ T cells. RESULTS: We found that 74% of HPSCC cases in our cohort were characterized by an immune-inflamed TME. Immune-inflamed patterns demonstrated an inferior survival with a significantly increased density of CD163+ tumor-associated macrophages and Foxp3+ regulatory T cells. Additionally, the inflamed tumor showed increased expression of PD-L1, without IFN-γ upregulation. CONCLUSIONS: The immune-inflamed pattern is the predominant preexisting immune phenotype in HPSCC and demonstrates immunosuppressive immune cell recruitment.


Asunto(s)
Carcinoma , Neoplasias Hipofaríngeas , Humanos , Antígeno B7-H1/metabolismo , Linfocitos Infiltrantes de Tumor/metabolismo , Linfocitos T CD8-positivos/metabolismo , Pronóstico , Microambiente Tumoral , Neoplasias Hipofaríngeas/patología , Carcinoma/patología
6.
Neurophotonics ; 9(4): 045007, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36466187

RESUMEN

Significance: Resting state functional connectivity (RSFC) can be used to assess autism spectrum disorder (ASD). Measuring RSFC usually takes 5 to 10 min, during which children with ASD may have difficulty keeping their heads motionless. Therefore, a short acquisition time for RSFC would make clinical implementation more feasible. Aim: To find a suitable acquisition time necessary for measuring RSFC with functional near-infrared spectroscopy (fNIRS) for the differentiation between children with ASD and typically developing (TD) children. Approach: We used fNIRS to record the spontaneous hemodynamic fluctuations from the bilateral temporal lobes of 25 children with ASD and 22 TD children. The recorded signals were truncated into several segments with different time windows, and then the homotopic RSFC was computed for each of these segments and compared between the two groups. Results: We observed even in a very short time duration of 0.5 min, the RSFC had already existed a significant difference between the two groups, and 2.0 min might be the minimal time required for measuring RSFC for accurate differentiation between the two groups. Conclusions: The fNIRS-RSFC acquired even in a short time, e.g., 2.0 min, might be a reliable feature for the differentiation between children with ASD and TD children.

7.
Brain Sci ; 11(11)2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34827466

RESUMEN

To investigate the relationship between short-range and homotopic long-range resting state functional connectivity (RSFC) in children with autism spectrum disorder (ASD) and typically developing (TD) children, we analyzed functional near-infrared spectroscopy (fNIRS) RSFC in 25 children with ASD and 22 age-matched TD children. The resting state fNIRS signals, including spontaneous fluctuations in the oxygenated hemoglobin (HbO2) and deoxygenated hemoglobin (Hb) concentrations, were recorded from the bilateral temporal lobes. We found that (1) there was no difference in the short-range RSFC between the left and right hemisphere in either ASD or TD group; (2) both the short-range and homotopic long-range RSFC were weaker in the ASD than TD group; and (3) the short-range RSFC was stronger than the homotopic long-range RSFC in the ASD group, whereas no such difference was observed in the TD group. These observations might be helpful for a better understanding of the underlying cortical mechanism in ASD.

8.
Front Hum Neurosci ; 15: 643410, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34211379

RESUMEN

Hemispheric asymmetry in the power spectrum of low-frequency spontaneous hemodynamic fluctuations has been previously observed in autism spectrum disorder (ASD). This observation may imply a specific narrow-frequency band in which individuals with ASD could show more significant alteration in resting-state functional connectivity (RSFC). To test this assumption, we evaluated narrowband RSFC at several frequencies for functional near-infrared spectroscopy signals recorded from the bilateral temporal lobes on 25 children with ASD and 22 typically developing (TD) children. In several narrow-frequency bands, we observed altered interhemispheric RSFC in ASD. However, in the band of 0.01-0.02 Hz, more mirrored channel pairs (or cortical sites) showed significantly weaker RSFC in the ASD group. Receiver operating characteristic analysis further demonstrated that RSFC in the narrowband of 0.01-0.02 Hz might have better differentiation ability between the ASD and TD groups. This may indicate that the narrowband RSFC could serve as a characteristic for the prediction of ASD.

9.
Physiol Meas ; 42(8)2021 08 27.
Artículo en Inglés | MEDLINE | ID: mdl-34315139

RESUMEN

Objective.Feature extraction and recognition in brain signal processing is of great significance for understanding the neurological mechanism of autism spectrum disorder (ASD). Resting-state (RS) functional near-infrared spectroscopy measurement provides a way to investigate the possible alteration in ASD-related complexity of resting-state (RS) functional near-infrared spectroscopy (fNIRS) signals and to explore the relationship between brain functional connectivity and complexity.Approach.Using the multiscale entropy (MSE) of fNIRS signals recorded from the bilateral temporal lobes (TLs) on 25 children with ASD and 22 typical development (TD) children, the pattern of brain complexity was assessed for both the ASD and TD groups.Main results.The quantitative analysis of MSE revealed the increased complexity in RS-fNIRS in children with ASD, particularly in the left temporal lobe. The complexity in the RS signal and resting state functional connectivity (RSFC) were also observed to exhibit negative correlation in the medium magnitude.Significance.These results indicated that the MSE might serve as a novel measure for RS-fNIRS signals in characterizing and understanding ASD.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Niño , Entropía , Humanos , Espectroscopía Infrarroja Corta , Lóbulo Temporal
10.
Front Immunol ; 11: 594775, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33424843

RESUMEN

Interferon-stimulated gene 15 (ISG15) is known to be involved in tumor progression. We previously reported that ISG15 expressed on nasopharyngeal carcinoma (NPC) cells and related to poor prognosis of patients with NPC. We further observed that ISG15 can be secreted by NPC cell and expressed on the macrophages in situ. However, the role of ISG15 in tumor-associated macrophages (TAMs) remains poorly understood. In the present study, we found that ISG15 treatment induces macrophages with M2-like phenotype, and the enhancement of NPC cell migration and tumorigenicity. Mechanically, ISG15-induced M2-like phenotype is dependent on the interaction with its receptor, LFA-1, and engagement of SRC family kinase (SFK) signal, and the subsequent secretion of CCL18. Blocking LFA-1, or SRC signal with small molecular inhibitors, or neutralizing with anti-CCL18 antibody can impede the activation of LFA-1-SFK-CCL18 axis in ISG15-treated macrophages. Clinically, ISG15+ CD163+ TAMs related to impaired survival of patients and advanced tumor stage of NPC. Furthermore, we found ISG15+ CD163+ macrophages inhibited antitumor CD8+ cells responses in NPC. Together, our findings suggested tumor cell-secreted ISG15, which acted as a tumor microenvironmental factor, induces M2-like phenotype, promoting tumor progression and suppression of cytotoxic T lymphocyte response.


Asunto(s)
Movimiento Celular/inmunología , Citocinas/inmunología , Tolerancia Inmunológica , Macrófagos/inmunología , Proteínas de Neoplasias/inmunología , Neoplasias/inmunología , Ubiquitinas/inmunología , Adulto , Anciano , Femenino , Humanos , Macrófagos/patología , Masculino , Persona de Mediana Edad , Neoplasias/patología
11.
Opt Express ; 26(17): 22419-22431, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30130936

RESUMEN

Probing suspended particles in seawater, such as microalgae, microplastics and silts, is very important for environmental monitoring and ecological research. We propose a method based on polarized light scattering to differentiate different suspended particles massively and rapidly. The optical path follows a similar design of a commonly used marine instrument, BB9, which records backscattering of non-polarized light at 120°. In addition, polarization elements are added to the incident and scattering path for taking polarization measurements. Experiments with polystyrene microspheres, porous polystyrene microspheres, silicon dioxide microspheres, and different marine microalgae show that by carefully choosing the incident polarization state and analyzing the polarization features of the scattered light at 120°, these particles can be effectively differentiated. Simulations based on the Mie scattering theory and discrete dipole approximation (DDA) have also been conducted for particles of different sizes, shapes and refractive indices, which help to understand the relationship between the polarization features and the physical properties of the particles. The laboratory system may serve as a prove-of-concept prototype of new instrumentations for applications on board or even with submersibles.

12.
Appl Opt ; 50(30): 5780-7, 2011 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-22015404

RESUMEN

An oscillatory-like relaxation process in which there are two valleys in the T-t curve is observed when light is transmitted through binary ferrofluids composed of both ferrimagnetic CoFe(2)O(4) nanoparticles and paramagnetic p-MgFe(2)O(4) nanoparticles in the presence of a high magnetic field and through pure (single) CoFe(2)O(4) ferrofluids in a low magnetic field. This relaxation behavior is explained using a model of a bidispersed system based on both chained and unchained particles. In such a bidispersed system, the variation of the transmitted light results mainly from the motion of the chains, with the polarized unchained particles' gas producing the modulation effect. The oscillatory-like relaxation phenomenon depends on the features of both the chained and unchained particle systems. If either the particle volume fraction of chained particles or of unchained particles is very low, or the degree of polarization of the unchained particles gas is very weak, a simple nonlinear relaxation process, giving only a valley in the T-t curve, will appear for the transmitted light. For pure CoFe(2)O(4) ferrofluids, the number of chained and unchained particles does not remain constant under different values of the magnetic field. According to the analysis of the relaxation behavior of transmitted light, it is known that binary ferrofluids based on strong magnetic CoFe(2)O(4) particles and weak magnetic p-MgFe(2)O(4) particles can be much closer to the theoretical bidispersed system than single ferrofluids containing only strong magnetic particles.

13.
Phys Rev E Stat Nonlin Soft Matter Phys ; 82(2 Pt 1): 021403, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20866805

RESUMEN

CoFe2O4 nanoparticles are ferrimagnetic and p-MgFe2O4 nanoparticles are paramagnetic. Binary ferrofluids can be synthesized by mixing CoFe2O4 ferrofluids and p-MgFe2O4 fluids in such a way that the magnetic interaction of the CoFe2O4 particles is large enough to form field-induced chainlike aggregates. The field modulation of light transmission through films of CoFe{2}O{4}-p-MgFe2O4 binary ferrofluids with different values of applied magnetic field is compared with pure CoFe2O4 ferrofluids. The experimental results revealed that the light transmission coefficient of binary ferrofluids can be more intensely modulated by an external magnetic field than pure CoFe2O4 ferrofluids. These show that in the binary ferrofluids, the field-induced structure mainly arises from the CoFe2O4 nanoparticle system and the p-MgFe2O4 nanoparticles introduce a nonlinear modulation effect, even though the microstructure of p-MgFe2O4 fluids is not affected by an applied magnetic field. Using a model of magnetic bidispersal, the enhanced field modulation of the light transmission through binary ferrofluids is explained by the coupling of geometric shadowing effects from both the CoFe2O4 and p-MgFe2O4 particle systems.

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