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1.
BMC Med ; 22(1): 56, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317226

RESUMO

BACKGROUND: A comprehensive overview of artificial intelligence (AI) for cardiovascular disease (CVD) prediction and a screening tool of AI models (AI-Ms) for independent external validation are lacking. This systematic review aims to identify, describe, and appraise AI-Ms of CVD prediction in the general and special populations and develop a new independent validation score (IVS) for AI-Ms replicability evaluation. METHODS: PubMed, Web of Science, Embase, and IEEE library were searched up to July 2021. Data extraction and analysis were performed for the populations, distribution, predictors, algorithms, etc. The risk of bias was evaluated with the prediction risk of bias assessment tool (PROBAST). Subsequently, we designed IVS for model replicability evaluation with five steps in five items, including transparency of algorithms, performance of models, feasibility of reproduction, risk of reproduction, and clinical implication, respectively. The review is registered in PROSPERO (No. CRD42021271789). RESULTS: In 20,887 screened references, 79 articles (82.5% in 2017-2021) were included, which contained 114 datasets (67 in Europe and North America, but 0 in Africa). We identified 486 AI-Ms, of which the majority were in development (n = 380), but none of them had undergone independent external validation. A total of 66 idiographic algorithms were found; however, 36.4% were used only once and only 39.4% over three times. A large number of different predictors (range 5-52,000, median 21) and large-span sample size (range 80-3,660,000, median 4466) were observed. All models were at high risk of bias according to PROBAST, primarily due to the incorrect use of statistical methods. IVS analysis confirmed only 10 models as "recommended"; however, 281 and 187 were "not recommended" and "warning," respectively. CONCLUSION: AI has led the digital revolution in the field of CVD prediction, but is still in the early stage of development as the defects of research design, report, and evaluation systems. The IVS we developed may contribute to independent external validation and the development of this field.


Assuntos
Inteligência Artificial , Doenças Cardiovasculares , Humanos , Doenças Cardiovasculares/diagnóstico , Medição de Risco/métodos , Programas de Rastreamento/métodos , Reprodutibilidade dos Testes
2.
Nicotine Tob Res ; 26(4): 474-483, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-37535700

RESUMO

INTRODUCTION: Electronic cigarettes (E-cigs) are in a controversial state. Although E-cig aerosol generally contains fewer harmful substances than smoke from burned traditional cigarettes, aerosol along with other compounds of the E-cigs may also affect lung functions and promote the development of lung-related diseases. We investigated the effects of E-cig on the pulmonary functions of male C57BL/6 mice and reveal the potential underlying mechanisms. METHODS: A total of 60 male C57BL/6 mice were randomly divided into four groups. They were exposed to fresh-air, traditional cigarette smoke, E-cig vapor with 12 mg/mL of nicotine, and E-cig with no nicotine for 8 weeks. Lung functions were evaluated by using quantitative analysis of the whole body plethysmograph, FlexiVent system, lung tissue histological and morphometric analysis, and RT-PCR analysis of mRNA expression of inflammation-related genes. In addition, the effects of nicotine and acrolein on the survival rate and DNA damage were investigated using cultured human alveolar basal epithelial cells. RESULTS: Exposure to E-cig vapor led to significant changes in lung functions and structures including the rupture of the alveolar cavity and enlarged alveolar space. The pathological changes were also accompanied by increased expression of interleukin-6 and tumor necrosis factor-α. CONCLUSIONS: The findings of the present study indicate that the safety of E-cig should be further evaluated. IMPLICATIONS: Some people currently believe that using nicotine-free E-cigs is a safe way to smoke. However, our research shows that E-cigs can cause lung damage regardless of whether they contain nicotine.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Camundongos , Animais , Masculino , Humanos , Nicotina/efeitos adversos , Nicotina/metabolismo , Camundongos Endogâmicos C57BL , Pulmão , Aerossóis/farmacologia
3.
J Med Internet Res ; 26: e63367, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39238480

RESUMO

BACKGROUND: As the global population ages, we witness a broad scientific and technological revolution tailored to meet the health challenges of older adults. Over the past 25 years, technological innovations, ranging from advanced medical devices to user-friendly mobile apps, are transforming the way we address these challenges, offering new avenues to enhance the quality of life and well-being of the aging demographic. OBJECTIVE: This study aimed to systematically review the development trends in technology for managing and caring for the health of older adults over the past 25 years and to project future development prospects. METHODS: We conducted a comprehensive bibliometric analysis of literatures related to technology-based solutions for health challenges in aging, published up to March 18, 2024. The search was performed using the Web of Science Core Collection, covering a span from 1999 to 2024. Our search strategy was designed to capture a broad spectrum of terms associated with aging, health challenges specific to older adults, and technological interventions. RESULTS: A total of 1133 publications were found in the Web of Science Core Collection. The publication trend over these 25 years showed a gradual but fluctuating increase. The United States was the most productive country and participated in international collaboration most frequently. The predominant keywords identified through this analysis included "dementia," "telemedicine," "older-adults," "telehealth," and "care." The keywords with citation bursts included "telemedicine" and "digital health." CONCLUSIONS: The scientific and technological revolution has significantly improved older adult health management, particularly in chronic disease monitoring, mobility, and social connectivity. The momentum for innovation continues to build, with future research likely to focus on predictive analytics and personalized health care solutions, further enhancing older adults' independence and quality of life.


Assuntos
Envelhecimento , Bibliometria , Humanos , Idoso , Qualidade de Vida , Telemedicina/tendências , Telemedicina/estatística & dados numéricos
4.
J Med Internet Res ; 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39168813

RESUMO

BACKGROUND: Internet hospitals (IHs) have rapidly developed as a promising strategy to address supply-demand imbalances in China's medical industry, with their capabilities directly dependent on information platform functionality. Moreover, a novel theory of "Trinity" smart hospital has provided advanced guidelines of IHs construction. OBJECTIVE: To explore the construction experience, construction models, and development prospects based on operational data from IHs. METHODS: Based on existing information systems and internet service functionalities, our hospital has built a "Smart Hospital Internet Information Platform (SHIIP)" for IHs operation, actively to expand online services, digitalize traditional healthcare, and explore healthcare services modes throughout the entire process and lifecycle. This article encompasses the platform architecture design, technological applications, patient service content and processes, healthcare professional support features, administrative management tools, and associated operational data. RESULTS: Our platform has presented a remarkable set of data, including 82,279,669 visits, 420,120 online medical consultations, 124,422 electronic prescriptions, 92,285 medication deliveries, 6,965,566 pre-diagnosis triages, 4,995,824 offline outpatient appointments, 2,025 medical education articles with a total of 15,148,310 views, and so on. These data demonstrate the significant role of IH as an indispensable component of our physical hospital services, with a deep integration between online and offline healthcare systems. CONCLUSIONS: Attributing to extreme convenience and improved efficiency, our IH has achieved a wide recognition and use from both the public and healthcare workers, and the upward trends in multiple data metrics suggest a promising outlook for its sustained and positive development in the future. Our pioneering exploration holds tremendous significance and serves as a valuable guiding reference for IHs construction and the progressive development of the internet healthcare sector.

5.
J Med Internet Res ; 26: e47645, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-38869157

RESUMO

In recent years, there has been explosive development in artificial intelligence (AI), which has been widely applied in the health care field. As a typical AI technology, machine learning models have emerged with great potential in predicting cardiovascular diseases by leveraging large amounts of medical data for training and optimization, which are expected to play a crucial role in reducing the incidence and mortality rates of cardiovascular diseases. Although the field has become a research hot spot, there are still many pitfalls that researchers need to pay close attention to. These pitfalls may affect the predictive performance, credibility, reliability, and reproducibility of the studied models, ultimately reducing the value of the research and affecting the prospects for clinical application. Therefore, identifying and avoiding these pitfalls is a crucial task before implementing the research. However, there is currently a lack of a comprehensive summary on this topic. This viewpoint aims to analyze the existing problems in terms of data quality, data set characteristics, model design, and statistical methods, as well as clinical implications, and provide possible solutions to these problems, such as gathering objective data, improving training, repeating measurements, increasing sample size, preventing overfitting using statistical methods, using specific AI algorithms to address targeted issues, standardizing outcomes and evaluation criteria, and enhancing fairness and replicability, with the goal of offering reference and assistance to researchers, algorithm developers, policy makers, and clinical practitioners.


Assuntos
Doenças Cardiovasculares , Aprendizado de Máquina , Humanos , Reprodutibilidade dos Testes , Algoritmos
6.
Scand Cardiovasc J ; 52(6): 367-371, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30668175

RESUMO

OBJECTIVE: To evaluate the effects of miR-210 on cardiac stem cells (CSCs) against hypoxia-induced injury. METHODS: CSCs were isolated from rat ventricular wall and cultured until passage 4. After exposure to hypoxia for 6 h, the expression of miR-210 was determined. Thereafter, transfection of miR-210 mimic and inhibitor was carried out. 1 week later, in vitro experiments were performed to measure the expression of caspase-8-associated protein 2 (Casp8ap2), Caspase 8, protein tyrosine phosphatase, non-receptor type 2 (PTPN2) and CXC chemokine receptor 4 (CXCR4), as well as migration and apoptosis of CSCs under hypoxic condition. RESULTS: Hypoxia induced a significant up-regulation of miR-210 expression in CSCs. Notably, the expression of Casp8ap2, Caspase8, PTPN2 was dramatically inhibited by overexpression of miR-210 in CSCsmiR-210 Group (P < .05), but no changes in CXCR4 (P > .05), compared with the control. Additionally, a decreased apoptosis of CSCs was detected in CSCsmiR-210 Group (26.22 ± 1.15%, P < .001), compared with Control Group (34.97 ± 0.63%). Moreover, the migration of CSCs was significantly promoted in CSCsmiR-210 Group (45.73 ± 2.4, P < .001), compared with Control Group (19.6 ± 1.11). Meanwhile, down-regulation of miR-210 reversed these results (P < .05). CONCLUSIONS: miR-210 was a hypoxia responsive element in CSCs, and its up-regulation inhibited apoptosis of CSCs and promoted their migration under hypoxic condition, through regulating its target genes Casp8ap2/Caspase 8 and PTPN2, which may provide a new strategy for cell therapy of ischemic heart disease.


Assuntos
Apoptose , MicroRNAs/metabolismo , Miócitos Cardíacos/metabolismo , Células-Tronco/metabolismo , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 8/genética , Caspase 8/metabolismo , Hipóxia Celular , Movimento Celular , Células Cultivadas , MicroRNAs/genética , Miócitos Cardíacos/patologia , Fenótipo , Proteína Tirosina Fosfatase não Receptora Tipo 2/genética , Proteína Tirosina Fosfatase não Receptora Tipo 2/metabolismo , Ratos Sprague-Dawley , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Transdução de Sinais , Células-Tronco/patologia , Regulação para Cima
7.
Nat Commun ; 15(1): 8575, 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39362860

RESUMO

Dysregulation of brain homeostasis is associated with neuropsychiatric conditions such as major depressive disorder. However, underlying neural-circuit mechanisms remain not well-understood. We show in mice that chronic restraint stress (CRS) and social defeat stress (SDS) are both associated with disruption of excitation (E)-inhibition (I) balance, with increased E/I ratios, in medial preoptic area (MPOA) circuits, but through affecting different neuronal types. CRS results in elevated activity in glutamatergic neurons, and their suppression mitigates CRS-induced depressive-like behaviors. Paraventricular hypothalamic input to these neurons contributes to induction but not expression of depressive-like behaviors. Their projections to ventral tegmental area and periaqueductal gray/dorsal raphe suppress midbrain dopaminergic and serotonergic activity, respectively, and mediate expression of divergent depressive-like symptoms. By contrast, SDS results in reduced activity of GABAergic neurons, and their activation alleviates SDS-induced depressive-like behaviors. Thus, E/I imbalance with relatively increased excitation in MPOA circuits may be a general mechanism underlying depression caused by different etiological factors.


Assuntos
Depressão , Neurônios GABAérgicos , Área Pré-Óptica , Estresse Psicológico , Animais , Área Pré-Óptica/metabolismo , Estresse Psicológico/complicações , Estresse Psicológico/fisiopatologia , Depressão/etiologia , Depressão/metabolismo , Depressão/fisiopatologia , Camundongos , Masculino , Neurônios GABAérgicos/metabolismo , Camundongos Endogâmicos C57BL , Área Tegmentar Ventral/fisiopatologia , Derrota Social , Comportamento Animal , Neurônios/metabolismo , Restrição Física , Modelos Animais de Doenças , Vias Neurais/fisiopatologia , Núcleo Hipotalâmico Paraventricular/metabolismo
8.
Curr Biol ; 2024 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-39265569

RESUMO

Sleeping animals can be woken up rapidly by external threat signals, which is an essential defense mechanism for survival. However, neuronal circuits underlying the fast transmission of sensory signals for this process remain unclear. Here, we report in mice that alerting sound can induce rapid awakening within hundreds of milliseconds and that glutamatergic neurons in the pontine central gray (PCG) play an important role in this process. These neurons exhibit higher sensitivity to auditory stimuli in sleep than wakefulness. Suppressing these neurons results in reduced sound-induced awakening and increased sleep in intrinsic sleep/wake cycles, whereas their activation induces ultra-fast awakening from sleep and accelerates awakening from anesthesia. Additionally, the sound-induced awakening can be attributed to the propagation of auditory signals from the PCG to multiple arousal-related regions, including the mediodorsal thalamus, lateral hypothalamus, and ventral tegmental area. Thus, the PCG serves as an essential distribution center to orchestrate a global auditory network to promote rapid awakening.

9.
Int Immunopharmacol ; 134: 112224, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38723370

RESUMO

Immunotherapy is becoming increasingly important, but the overall response rate is relatively low in the treatment of gastric cancer (GC). The application of tumor mutational burden (TMB) in predicting immunotherapy efficacy in GC patients is limited and controversial, emphasizing the importance of optimizing TMB-based patient selection. By combining TMB and major histocompatibility complex (MHC) related hub genes, we established a novel TM-Score. This score showed superior performance for immunotherapeutic selection (AUC = 0.808) compared to TMB, MSI status, and EBV status. Additionally, it predicted the prognosis of GC patients. Subsequently, a machine learning model adjusted by the TM-Score further improved the accuracy of survival prediction (AUC > 0.8). Meanwhile, we found that GC patients with low TM-Score had a higher mutation frequency, higher expression of HLA genes and immune checkpoint genes, and higher infiltration of CD8+ T cells, CD4+ helper T cells, and M1 macrophages. This suggests that TM-Score is significantly associated with tumor immunogenicity and tumor immune environment. Notably, based on the RNA-seq and scRNA-seq, it was found that AKAP5, a key component gene of TM-Score, is involved in anti-tumor immunity by promoting the infiltration of CD4+ T cells, NK cells, and myeloid cells. Additionally, siAKAP5 significantly reduced MHC-II mRNA expression in the GC cell line. In addition, our immunohistochemistry assays confirmed a positive correlation between AKAP5 and human leukocyte antigen (HLA) expression. Furthermore, AKAP5 levels were higher in patients with longer survival and those who responded to immunotherapy in GC, indicating its potential value in predicting prognosis and immunotherapy outcomes. In conclusion, TM-Score, as an optimization of TMB, is a more precise biomarker for predicting the immunotherapy efficacy of the GC population. Additionally, AKAP5 shows promise as a therapeutic target for GC.


Assuntos
Imunoterapia , Aprendizado de Máquina , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/terapia , Neoplasias Gástricas/genética , Neoplasias Gástricas/mortalidade , Imunoterapia/métodos , Prognóstico , Biomarcadores Tumorais/genética , Proteínas de Ancoragem à Quinase A/genética , Microambiente Tumoral/imunologia , Mutação , Resultado do Tratamento
10.
Small ; 9(19): 3218-23, 2013 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-23585358

RESUMO

Soluble covalent organic nanoframeworks up to generation 2.5 (G2.5) are synthesized with self-similar H-shaped conformations by using a bottom-up approach including iterative C-H bond functionalization. The electrical characteristics of nanoscale thin-film semiconductors of the conjugation-interrupted frameworks can be tuned by post-modification with diazonium salt.

11.
Exp Cell Res ; 318(4): 391-9, 2012 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-22146760

RESUMO

OBJECTIVE: To investigate whether transmyocardial drilling revascularization combined with heparinized basic fibroblast growth factor (bFGF)-incorporating degradable stent implantation (TMDRSI) can promote myocardial regeneration after acute myocardial infarction (AMI). METHODS: A model of AMI was generated by ligating the mid-third of left anterior descending artery (LAD) of miniswine. After 6 h, the animals were divided into none-treatment (control) group (n=6) and TMDRSI group (n=6). For TMDRSI group, two channels with 3.5 mm in diameter were established by a self-made drill in the AMI region, into which a stent was implanted. Expression of stromal cell-derived factor-1(α) (SDF-1(α)) and CXC chemokine receptor 4 (CXCR4), cardiac stem cell (CSC)-mediated myocardial regeneration, myocardial apoptosis, myocardial viability, and cardiac function were assessed at various time-points. RESULTS: Six weeks after the operation, CSCs were found to have differentiated into cardiomyocytes to repair the infarcted myocardium, and all above indices showed much improvement in the TMDRSI group compared with the control group (P<0.001). CONCLUSIONS: The new method has shown to be capable of promoting CSCs proliferation and differentiation into cardiomyocytes through activating the SDF-1/CXCR4 axis, while inhibiting myocardial apoptosis, thereby enhancing myocardial regeneration following AMI and improving cardiac function. This may provide a new strategy for myocardial regeneration following AMI.


Assuntos
Quimiocina CXCL12/fisiologia , Stents Farmacológicos , Fator 2 de Crescimento de Fibroblastos/administração & dosagem , Heparina/administração & dosagem , Receptores CXCR4/fisiologia , Células-Tronco/efeitos dos fármacos , Revascularização Transmiocárdica a Laser/métodos , Animais , Animais Recém-Nascidos , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Terapia Combinada , Fator 2 de Crescimento de Fibroblastos/química , Expressão Gênica , Heparina/química , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Implantação de Prótese/métodos , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Regeneração/efeitos dos fármacos , Regeneração/genética , Regeneração/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Células-Tronco/metabolismo , Células-Tronco/patologia , Células-Tronco/fisiologia , Suínos , Porco Miniatura , Fibrilação Ventricular/tratamento farmacológico , Fibrilação Ventricular/patologia , Fibrilação Ventricular/cirurgia
12.
Int J Mol Sci ; 14(11): 22368-79, 2013 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-24232455

RESUMO

Supramolecular luminescence stems from non-covalent exciton behaviors of active π-segments in supramolecular entities or aggregates via intermolecular forces. Herein, a π-conjugated oligofluorenol, containing self-complementary double hydrogen bonds, was synthesized using Suzuki coupling as a supramolecular semiconductor. Terfluorenol-based random supramolecular polymers were confirmed via concentration-dependent nuclear magnetic resonance (NMR) and dynamic light scattering (DLS). The photoluminescent spectra of the TFOH-1 solution exhibit a green emission band (g-band) at approximately ~520 nm with reversible features, as confirmed through titration experiments. Supramolecular luminescence of TFOH-1 thin films serves as robust evidence for the aggregates of g-band. Our results suggest that the presence of polyfluorene ketone defects is a sufficient condition, rather than a sufficient-necessary condition for the g-band. Supramolecular electroluminescence will push organic devices into the fields of supramolecular optoelectronics, spintronics, and mechatronics.


Assuntos
Fluorenos/química , Luminescência , Polímeros/química , Semicondutores , Ligação de Hidrogênio , Espectroscopia de Ressonância Magnética
13.
Radiol Oncol ; 57(4): 530-537, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038420

RESUMO

BACKGROUND: Cardioprotection is valued in radiotherapy for patients with left-sided breast cancer. Deep inspiration breath-hold (DIBH) technique can achieve cardioprotection well. However, during DIBH, the extent to which the heart enters the radiation field is affected by the movement of the thorax and diaphragm. The aim of this study was to analyze the correlation between the maximum distance of the heart entering the field (maximum heart distance, MHD) and thoracic diameter changes and diaphragmatic descent in left-sided breast cancer patients during DIBH. PATIENTS AND METHODS: Ninety-eight patients with left-sided breast cancer were included in this retrospective study. They performed simulation in Sentinel-guided DIBH, and two sets of CT images were collected under both free breathing (FB) and DIBH, and diaphragm positions, anteroposterior thoracic diameter (ATD), transverse thoracic diameter (TTD), gating window level (GWL), and MHD were measured, and the change (Δ) of each parameter in DIBH relative to that in FB were calculated. Pearson or Spearman test were used to analyze the correlation between ΔMHD and the changes in other parameters. RESULTS: For all patients with DIBH, the average of ΔMHD was -8.3 mm, and the average of ΔATD and ΔTTD were 11.0 and 8.6 mm, and the median of both left diaphragmatic descent (LDD) and right diaphragmatic descent (RDD) were 35.0 mm, and the median of GWL was 11.1 mm. The correlation coefficients between MHD decrease (ΔMHD) and LDD, RDD, and ΔTTD were -0.430 (p = 0.000), -0.592 (p = 0.000) and 0.208 (p = 0.040), respectively, but not significantly correlated with ΔATD or GWL. CONCLUSIONS: The MHD decrease showed a moderate correlation with diaphragmatic descent In Sentinel-guided DIBH for patients with left-sided breast cancer, while there was a weak or no correlation with thoracic diameter changes or GWL. Abdominal breathing can lower diaphragm more and may be more beneficial to the heart stay away from tangential field.


Assuntos
Neoplasias da Mama , Neoplasias Unilaterais da Mama , Humanos , Feminino , Diafragma/diagnóstico por imagem , Suspensão da Respiração , Dosagem Radioterapêutica , Neoplasias Unilaterais da Mama/diagnóstico por imagem , Neoplasias Unilaterais da Mama/radioterapia , Estudos Retrospectivos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/radioterapia , Tórax
14.
Front Public Health ; 11: 1219407, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37546298

RESUMO

Recently, in order to comprehensively promote the development of medical institutions and solve the nationwide problems in the healthcare fields, the government of China developed an innovative national policy of "Trinity" smart hospital construction, which includes "smart medicine," "smart services," and "smart management". The prototype of the evaluation system has been established, and a large number of construction achievements have emerged in many hospitals. In this article, the summary of this field was performed to provide a reference for medical workers, managers of hospitals, and policymakers.


Assuntos
Atenção à Saúde , Arquitetura Hospitalar , Humanos , China , Políticas , Hospitais
15.
Nat Neurosci ; 26(9): 1529-1540, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37524978

RESUMO

Fluctuations in reproductive hormone levels are associated with mood disruptions in women, such as in postpartum and perimenopausal depression. However, the neural circuit mechanisms remain unclear. Here we report that medial preoptic area (MPOA) GABAergic neurons mediate multifaceted depressive-like behaviors in female mice after ovarian hormone withdrawal (HW), which can be attributed to downregulation of activity in Esr1 (estrogen receptor-1)-expressing GABAergic neurons. Enhancing activity of these neurons ameliorates depressive-like behaviors in HW-treated mice, whereas reducing their activity results in expression of these behaviors. Two separate subpopulations mediate different symptoms: a subpopulation projecting to the ventral tegmental area (VTA) mediates anhedonia and another projecting to the periaqueductal gray mediates immobility. These projections enhance activity of dopaminergic neurons in the VTA and serotonergic neurons in the dorsal raphe, respectively, with increased release of dopamine and serotonin, possibly through disinhibition mechanisms. Thus, the MPOA is a hub that mediates depressive-like behaviors resulting from transitions in reproductive hormone levels.


Assuntos
Área Pré-Óptica , Área Tegmentar Ventral , Camundongos , Feminino , Animais , Área Pré-Óptica/fisiologia , Área Tegmentar Ventral/fisiologia , Neurônios Dopaminérgicos/fisiologia , Neurônios GABAérgicos/fisiologia
16.
Front Aging Neurosci ; 15: 1213379, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37649717

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disorder primarily affecting cognitive functions. However, sensory deficits in AD start to draw attention due to their high prevalence and early onsets which suggest that they could potentially serve as diagnostic biomarkers and even contribute to the disease progression. This literature review examines the sensory deficits and cortical pathological changes observed in visual, auditory, olfactory, and somatosensory systems in AD patients, as well as in various AD animal models. Sensory deficits may emerge at the early stages of AD, or even precede the cognitive decline, which is accompanied by cortical pathological changes including amyloid-beta deposition, tauopathy, gliosis, and alterations in neuronal excitability, synaptic inputs, and functional plasticity. Notably, these changes are more pronounced in sensory association areas and superficial cortical layers, which may explain the relative preservation of basic sensory functions but early display of deficits of higher sensory functions. We propose that sensory impairment and the progression of AD may establish a cyclical relationship that mutually perpetuates each condition. This review highlights the significance of sensory deficits with or without cortical pathological changes in AD and emphasizes the need for further research to develop reliable early detection and intervention through sensory systems.

17.
Polymers (Basel) ; 15(13)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37447472

RESUMO

Polypropylene (PP) has gained attention in the industry as an environmentally friendly material. However, its electrical properties are compromised due to space charge accumulation during operation, limiting its application in high-voltage DC cable insulation. This study investigates the effect and mechanism of SiO2 with a DDS surface hydrophobic treatment on space charge suppression and the electrical properties of PP composites. The PP matrix was doped with SiO2 nanostructures, both with a DDS surface hydrophobic treatment and untreated as a control group. The functional group structure and dispersion of nanostructured SiO2 in the matrix were characterized. The findings reveal that the incorporation of SiO2 nanostructures effectively mitigates charge accumulation in PP composites. However, a high concentration of unsurfaced nanostructures tends to agglomerate, resulting in inadequate space charge suppression and a diminished DC breakdown field strength. Nonetheless, surface treatment improves the dispersion of SiO2 within the matrix. Notably, the composite containing 1.0 wt% of surface hydrophobic SiO2 exhibits the least space charge accumulation. Compared to the base material PP, the average charge density is reduced by 83.9% after the 1800 s short-circuit discharges. Moreover, its DC breakdown field strength reaches 3.45 × 108 V/m, surpassing pure PP by 19.4% and untreated SiO2/PP composites of the same proportion by 24.0%.

18.
Neuron ; 111(9): 1486-1503.e7, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-36893756

RESUMO

Extracting the valence of environmental cues is critical for animals' survival. How valence in sensory signals is encoded and transformed to produce distinct behavioral responses remains not well understood. Here, we report that the mouse pontine central gray (PCG) contributes to encoding both negative and positive valences. PCG glutamatergic neurons were activated selectively by aversive, but not reward, stimuli, whereas its GABAergic neurons were preferentially activated by reward signals. The optogenetic activation of these two populations resulted in avoidance and preference behavior, respectively, and was sufficient to induce conditioned place aversion/preference. Suppression of them reduced sensory-induced aversive and appetitive behaviors, respectively. These two functionally opponent populations, receiving a broad range of inputs from overlapping yet distinct sources, broadcast valence-specific information to a distributed brain network with distinguishable downstream effectors. Thus, PCG serves as a critical hub to process positive and negative valences of incoming sensory signals and drive valence-specific behaviors with distinct circuits.


Assuntos
Encéfalo , Neurônios GABAérgicos , Camundongos , Animais , Substância Cinzenta Periaquedutal , Afeto , Sinais (Psicologia)
19.
Nat Commun ; 14(1): 7278, 2023 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-37949869

RESUMO

In the mammalian visual system, the ventral lateral geniculate nucleus (vLGN) of the thalamus receives salient visual input from the retina and sends prominent GABAergic axons to the superior colliculus (SC). However, whether and how vLGN contributes to fundamental visual information processing remains largely unclear. Here, we report in mice that vLGN facilitates visually-guided approaching behavior mediated by the lateral SC and enhances the sensitivity of visual object detection. This can be attributed to the extremely broad spatial integration of vLGN neurons, as reflected in their much lower preferred spatial frequencies and broader spatial receptive fields than SC neurons. Through GABAergic thalamocollicular projections, vLGN specifically exerts prominent surround suppression of visuospatial processing in SC, leading to a fine tuning of SC preferences to higher spatial frequencies and smaller objects in a context-dependent manner. Thus, as an essential component of the central visual processing pathway, vLGN serves to refine and contextually modulate visuospatial processing in SC-mediated visuomotor behaviors via visually-driven long-range feedforward inhibition.


Assuntos
Corpos Geniculados , Neurônios , Camundongos , Animais , Corpos Geniculados/fisiologia , Neurônios/fisiologia , Tálamo , Vias Visuais/fisiologia , Colículos Superiores/fisiologia , Mamíferos
20.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(12): 3377-80, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23427571

RESUMO

The hyperspectral effective information of Gannan navel orange was extracted by genetic algorithm (GA) and successive projections algorithm (SPA) for partial least squares (PLS) model. Average spectral was extracted from region of interest (ROD) of hyperspectral images after preprocessing. GA and SPA were used to select 27 and 8 characteristic wavelengths for chlorophyll model with PLS. The correlation coefficients and rms error of GA-PLS were 0.80 and 2.45, and the correlation coefficients and rms error of SPA-PLS were 0.83 and 2.30, respectively. Overall results sufficiently demonstrate that SPA-PLS model has a greater advantage which can be combined with hyperspectral technique to be a nondestructive and rapid analytical method.


Assuntos
Algoritmos , Clorofila/análise , Citrus sinensis/química , Folhas de Planta/química , Análise Espectral/métodos , China , Análise dos Mínimos Quadrados , Modelos Teóricos
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