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1.
PLoS One ; 19(1): e0296789, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38241254

RESUMO

The recognition of food images is of great significance for nutrition monitoring, food retrieval and food recommendation. However, the accuracy of recognition had not been high enough due to the complex background of food images and the characteristics of small inter-class differences and large intra-class differences. To solve these problems, this paper proposed a food image recognition method based on transfer learning and ensemble learning. Firstly, generic image features were extracted by using the convolutional neural network models (VGG19, ResNet50, MobileNet V2, AlexNet) pre-trained on the ImageNet dataset. Secondly, the 4 pre-trained models were transferred to the food image dataset for model fine-tuning. Finally, different basic learner combination strategies were adopted to establish the ensemble model and classify feature information. In this paper, several kinds of experiments were performed to compare the results of food image recognition between single models and ensemble models on food-11 dataset. The experimental results demonstrated that the accuracy of the ensemble model was the highest, reaching 96.88%, which was superior to any base learner. Therefore, the convolutional neural network model based on transfer learning and ensemble learning has strong learning ability and generalization ability, and it is feasible and practical to apply the method to food image recognition.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação
3.
J Oncol ; 2021: 4553613, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34707659

RESUMO

OBJECTIVE: High levels of self-efficacy (SE) in colorectal cancer (CRC) patients and/or caregivers enable patients to cope with cancer, reduce caregiver burden, and promote quality of life (QOL) in patients and caregivers alike. This review aims to (a) identify the SE theory sources covered by SE interventions or interventions, including targeting improved SE for CRC patients and/or caregivers, to guide future development of SE interventions; and (b) explore intervention effects based on SE theory through meta-analysis. METHODS: Using five electronic databases-CINAHL, Cochrane Library, Embase, PsycINFO, and PubMed-a systematic search was performed in April 2021 to identify English or Chinese literature that studied improving SE interventions for CRC patients and/or caregivers. Manual screening of the articles' references list was also performed. RESULTS: A total of 18 studies were found to be suitable and included in this review. Of the 18 studies that were included, 10 randomized controlled trials (RCTs) studies with 917 participants were eligible for meta-analysis. Interventions provide support for SE drawing on different sources of information. Performance accomplishment (PA) is the key source, with vicarious experience (VE) and verbal persuasion (VP) assisting in improving PA. Reducing negative emotional arousal (NEA) and improving positive emotional arousal (PEA) are also indispensable factors in improving SE. The meta-analysis results show that interventions based on the SE theory can bring about positive effects for CRC patients and/or caregivers. CONCLUSIONS: Different sources of information aimed at improving SE, covered by the interventions, including PA, VE, VP, NEA, and PEA, have been explored. Positive intervention outcomes that focused on improving SE for CRC patients and/or caregivers were identified and highlighted. For future SE interventions, we advocate choosing combination sources of SE information to design interventions. It is recommended that future SE improvement interventions should focus on improving PA, supplemented by increasing VE, while reducing NEA and providing useful VP.

4.
Front Neurosci ; 15: 652996, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34025341

RESUMO

Proper circadian photoentrainment is crucial for the survival of many organisms. In mammals, intrinsically photosensitive retinal ganglion cells (ipRGCs) can use the photopigment melanopsin to sense light independently from rod and cone photoreceptors and send this information to many brain nuclei such as the suprachiasmatic nucleus (SCN), the site of the central circadian pacemaker. Here, we measure ionic currents and develop mathematical models of the electrical activity of two types of ipRGCs: M1, which projects to the SCN, and M4, which does not. We illustrate how their ionic properties differ, mainly how ionic currents generate lower spike rates and depolarization block in M1 ipRGCs. Both M1 and M4 cells have large geometries and project to higher visual centers of the brain via the optic nerve. Using a partial differential equation model, we show how axons of M1 and M4 cells faithfully convey information from the soma to the synapse even when the signal at the soma is attenuated due to depolarization block. Finally, we consider an ionic model of circadian photoentrainment from ipRGCs synapsing on SCN neurons and show how the properties of M1 ipRGCs are tuned to create accurate transmission of visual signals from the retina to the central pacemaker, whereas M4 ipRGCs would not evoke nearly as efficient a postsynaptic response. This work shows how ipRGCs and SCN neurons' electrical activities are tuned to allow for accurate circadian photoentrainment.

5.
Support Care Cancer ; 28(11): 5251-5262, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32103359

RESUMO

PURPOSE: Cancer and its treatment can affect quality of life (QOL) in cancer patient and family caregiver dyads. However, the factors influencing dyad QOL remain inconclusive. Our study was designed to (i) assess dyads' QOL, and examine the relationship between the QOL of cancer patients and that of their family caregivers, and (ii) investigate factors that may modify this relationship. METHODS: Participants comprised 641 cancer patient-family caregiver dyads. Four types of variables were collected as potential influencing factors, including cancer patient-related variables, family caregiver-related variables, family-related variables, and symptom distress-related variables. RESULTS: Generally, family caregivers reported better QOL than cancer patients did. The effect sizes of the correlation (r) between cancer patients' QOL and those of their family caregivers ranged from 0.08 to 0.27. Various variables influencing the QOL correlations between cancer patients and family caregivers were identified, including cancer patient-related variables (e.g., age, gender, marital status, understanding of the disease, cancer type and treatment); family caregiver-related variables (e.g., being the spouse or offspring of a patient, duration in their role as a family caregiver, understanding of the disease, and amount of time spent on caregiving each day); family-related variables (e.g., cancer patient enjoyed a good relationship with family pre-cancer diagnosis, family was experiencing serious or mild financial burden due to cancer treatment); and symptom stress-related variables (anxiety and depression). CONCLUSIONS: Study findings draw attention to QOL and its related factors in cancer patient-family caregiver dyads. This will benefit the development of interventions to improve dyad QOL.


Assuntos
Cuidadores , Relações Interpessoais , Neoplasias/epidemiologia , Neoplasias/psicologia , Qualidade de Vida , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Ansiedade/epidemiologia , Ansiedade/etiologia , Cuidadores/psicologia , Cuidadores/estatística & dados numéricos , China/epidemiologia , Estudos Transversais , Progressão da Doença , Família/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Fatores Socioeconômicos , Cônjuges/psicologia , Cônjuges/estatística & dados numéricos , Inquéritos e Questionários , Adulto Jovem
6.
Eur J Oncol Nurs ; 25: 16-23, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27865248

RESUMO

PURPOSE: The Hospital Anxiety and Depression Scale (HADS) acts as one of the most frequently used self-reported measures in cancer practice. The evidence for construct validity of HADS, however, remains inconclusive. The objective of this study is to evaluate the psychometric properties of the Chinese version HADS (C-HADS) in terms of construct validity, internal consistency reliability, and concurrent validity in dyads of Chinese cancer patients and their family caregivers. METHODS: This was a cross-sectional study, conducted in multiple centers: one hospital in each of the seven different administrative regions in China from October 2014 to May 2015. A total of 641 dyads, consisting of cancer patients and family caregivers, completed a survey assessing their demographic and background information, anxiety and depression using C-HADS, and quality of life (QOL) using Chinese version SF-12. Data analysis methods included descriptive statistics, confirmatory factor analysis (CFA), and Pearson correlations. RESULTS: Both the two-factor and one-factor models offered the best and adequate fit to the data in cancer patients and family caregivers respectively. The comparison of the two-factor and single-factor models supports the basic assumption of two-factor construct of C-HADS. The overall and two subscales of C-HADS in both cancer patients and family caregivers had good internal consistency and acceptable concurrent validity. CONCLUSIONS: The Chinese version of the HADS may be a reliable and valid screening tool, as indicated by its original two-factor structure. The finding supports the basic assumption of two-factor construct of HADS.


Assuntos
Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/etiologia , Cuidadores/psicologia , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/etiologia , Neoplasias/complicações , Neoplasias/psicologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos de Ansiedade/psicologia , Povo Asiático/psicologia , China , Estudos Transversais , Transtorno Depressivo/psicologia , Análise Fatorial , Família/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria/métodos , Qualidade de Vida/psicologia , Reprodutibilidade dos Testes , Autorrelato , Fatores Socioeconômicos , Inquéritos e Questionários , Traduções , Adulto Jovem
8.
PLoS One ; 9(10): e111172, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25361073

RESUMO

Stylosanthes sp. is the most important forage legume in tropical areas worldwide. Stylosanthes anthracnose, which is mainly caused by Colletotrichum gloeosporioides, is a globally severe disease in stylo production. Little progress has been made in anthracnose molecular pathogenesis research. In this study, Agrobacterium tumefaciens-mediated transformation was used to transform Stylosanthes colletotrichum strain CH008. The major factors of the genetic transformation system of S. colletotrichum were optimized as follows: A. tumefaciens' AGL-1 concentration (OD(600)), 0.8; concentration of Colletotrichum conidium, 1 × 10(6) conidia/mL; acetosyringone concentration, 100 mmol/L; induction time, 6 h; co-culture temperature, 25 °C; and co-culture time, 3 d. Thus, the transformation efficiency was increased to 300-400 transformants per 106 conidia. Based on the optimized system, a mutant library containing 4616 mutants was constructed, from which some mutants were randomly selected for analysis. Results show that the mutants were single copies that could be stably inherited. The growth rate, spore amount, spore germination rate, and appressorium formation rate in some mutants were significantly different from those in the wild-type strain. We then selected the most appropriate method for the preliminary screening and re-screening of each mutant's pathogenic defects. We selected 1230 transformants, and obtained 23 strains with pathogenic defects, namely, 18 strains with reduced pathogenicity and five strains with lost pathogenicity. Thermal asymmetric interlaced PCR was used to identify the transfer DNA (T-DNA) integration site in the mutant that was coded 2430, and a sequence of 476 bp was obtained. The flanking sequence of T-DNA was compared with the Colletotrichum genome by BLAST, and a sequence of 401 bp was found in Contig464 of the Colletotrichum genome. By predicting the function of the flanking sequence, we discovered that T-DNA insertion in the promoter region of the putative gene had 79% homology with the aspartate aminotransferase gene in Magnaporthe oryzae (XP_003719674.1).


Assuntos
Colletotrichum/genética , Genoma Fúngico , Biblioteca Genômica , Mutagênese Insercional , Agrobacterium tumefaciens/genética , Aspartato Aminotransferases/genética , Clonagem Molecular , Técnicas de Cocultura , Colletotrichum/patogenicidade , Elementos de DNA Transponíveis , Fabaceae/microbiologia , Vetores Genéticos , Regiões Promotoras Genéticas , Esporos Fúngicos/genética , Transformação Genética
9.
Biomacromolecules ; 15(11): 4249-59, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25329523

RESUMO

The applications of photodynamic therapy (PDT) are usually limited by photosensitizer's side effect and the singlet oxygen's short half-life. Herein, we demonstrate a dual-targeting (both cellular and subcellular targeting) strategy to enhance the PDT efficacy. A cationic porphyrin derivative (MitoTPP) was synthesized as the mitochondrion-targeting photosensitizer, and the dual-targeting PDT system was then fabricated by encapsulating MitoTPP into the acid-responsive and folic acid (FA)-modified polymer micelles. Under acidic pH, the micelles swell as a result of protonation of tertiary amines and disruption of the nucleobase pairing, thereby causing the release of the photosensitizer. Confocal microscope observation shows that the dual-targeting and micelle-based PDT system can preferably enter folate receptor (FR)-positive cancer cells, and upon cellular internalization, the MitoTPP molecules are released from the micelles and selectively accumulate in mitochondria. Under light irradiation, the singlet oxygen generated by the photosensitizer causes the oxidant damage to the mitochondrial and subsequently the apoptosis of the cells, as evidenced by the loss of mitochondrial membrane potential. Cell viability assays indicate that dual-targeting micelle-based systems exhibit enhanced cytotoxicity toward FR-positive cells. This study may provide a new approach for effectively enhancing the action of PDT systems.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Micelas , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células HeLa , Humanos , Camundongos , Fármacos Fotossensibilizantes/administração & dosagem
10.
Small ; 10(18): 3750-60, 2014 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-24833029

RESUMO

The therapeutic applications of exogenous nitric oxide are usually limited by its short half-life and its vulnerability to many biological substances, thus straightforward and precise spatiotemporal control of NO delivery may be critical to its therapeutic effects. Herein, the mitochondria-targeted and photoresponsive NO-releasing nanosystem is demonstrated as a new approach for cancer treatment. The nanosystem is fabricated by covalently incorporating a NO photo-donor and a mitochondria targeting ligand onto carbon-dots; accordingly, multi-functionalities (mitochondria-targeting, light-enhanced efficient NO-releasing, and cell imaging) are achieved. The in vitro NO release profiles for the nanosystem show that the duration of NO release from the present C-dot-based nanosystem containing immobilized SNO can be extended up to 8 hours or more. Upon cellular internalization, the nanosystem can target mitochondria and release NO. The action of the nanosystem on three cancer cell lines is evaluated; it is found that the targeted NO-releasing system can cause high cytotoxicity towards the cancer cells by specifically damaging their mitochondria. Additionally, light irradiation can amplify the cell apoptosis by enhancing NO release. These observations demonstrate that incorporating mitochondria-targeting ligand onto a NO-releasing system can enhance its pro-apoptosis action, thereby providing new insights for exploiting NO in cancer therapy.


Assuntos
Apoptose , Mitocôndrias/metabolismo , Nanopartículas/química , Nanotecnologia/métodos , Neoplasias/patologia , Óxido Nítrico/química , Carbono/química , Sobrevivência Celular , Corantes/química , Células HeLa , Humanos , Ligantes , Potenciais da Membrana/efeitos dos fármacos , Microscopia Confocal , Neoplasias/metabolismo , Neoplasias/terapia , Oxigênio/química , Tamanho da Partícula , Fotoquímica
11.
J Neurophysiol ; 109(7): 1876-89, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23343892

RESUMO

In the mammalian retina, some ganglion cells express the photopigment melanopsin and function as photoreceptors. Five morphological types of these intrinsically photosensitive retinal ganglion cells (ipRGCs), M1-M5, have been identified in mice. Whereas M1 specializes in non-image-forming visual functions and drives such behaviors as the pupillary light reflex and circadian photoentrainment, the other types appear to contribute to image-forming as well as non-image-forming vision. Recent work has begun to reveal physiological diversity among some of the ipRGC types, including differences in photosensitivity, firing rate, and membrane resistance. To gain further insights into these neurons' functional differences, we conducted a comprehensive survey of the electrophysiological properties of all five morphological types. Compared with the other types, M1 had the highest membrane resistance, longest membrane time constant, lowest spike frequencies, widest action potentials, most positive spike thresholds, smallest hyperpolarization-activated inwardly-rectifying current-induced "sagging" responses to hyperpolarizing currents, and the largest effects of voltage-gated K(+) currents on membrane potentials. M4 and M5 were at the other end of the spectrum for most of these measures, while M2 and M3 tended to be in the middle of this spectrum. Additionally, M1 and M2 cells generated more diverse voltage-gated Ca(2+) currents than M3-M5. In conclusion, M1 cells are significantly different from all other ipRGCs in most respects, possibly reflecting the unique physiological requirements of non-image-forming vision. Furthermore, the non-M1 ipRGCs are electrophysiologically heterogeneous, implicating these cells' diverse functional roles in both non-image-forming vision and pattern vision.


Assuntos
Potenciais de Ação , Células Fotorreceptoras de Vertebrados/fisiologia , Células Ganglionares da Retina/fisiologia , Animais , Canais de Cálcio/metabolismo , Potenciais da Membrana , Camundongos , Células Fotorreceptoras de Vertebrados/classificação , Células Fotorreceptoras de Vertebrados/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Células Ganglionares da Retina/classificação , Células Ganglionares da Retina/metabolismo
12.
Vis Neurosci ; 26(2): 177-87, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19275782

RESUMO

Retinal bipolar cells convey visual information from photoreceptors to retinal third-order neurons, amacrine and ganglion cells, with graded potentials through diversified cell types. To understand the possible role of voltage-dependent T-type Ca2+ currents in retinal bipolar cells, we investigated the pharmacological and biophysical properties of T-type Ca2+ currents in acutely dissociated retinal cone bipolar cells from rats using whole-cell patch-clamp recordings. We observed a broad group of cone bipolar cells with prominent T-type Ca2+ currents (T-rich) and another group with prominent L-type Ca2+ currents (L-rich). Based on the pharmacological and biophysical properties of the T-type Ca2+ currents, T-rich cone bipolar cells could be divided into three subgroups. Each subgroup appeared to express a single dominant T-type Ca2+ channel subunit. The T-type calcium currents could generate low-threshold regenerative potentials or spikes. Our results suggest that T-type Ca2+ channels may play an active and distinct signaling role in second-order neurons of the visual system, in contrast to the common signaling by L-rich bipolar cells.


Assuntos
Canais de Cálcio Tipo T/metabolismo , Células Bipolares da Retina/fisiologia , Animais , Canais de Cálcio Tipo L/metabolismo , Canais de Cálcio Tipo T/química , Técnicas de Cultura de Células , Linhagem Celular , Ditiotreitol/farmacologia , Humanos , Transporte de Íons , Potenciais da Membrana/efeitos dos fármacos , Níquel/farmacologia , Técnicas de Patch-Clamp , Subunidades Proteicas/metabolismo , Ratos , Ratos Long-Evans , Células Bipolares da Retina/efeitos dos fármacos , Bloqueadores dos Canais de Sódio/farmacologia , Tetrodotoxina/farmacologia , Oligoelementos/farmacologia
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