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Trauma type moderates the impact of trauma exposure on clinical symptomatology; however, the impact of trauma type on the neural correlates of emotion regulation is not as well understood. This study examines how violent and nonviolent trauma differentially influence the neural correlates of conditioned fear and extinction. We aggregated psychophysiological and fMRI data from three studies; we categorized reported trauma as violent or nonviolent, and subdivided violent trauma as sexual or nonsexual. We examined skin conductance responses (SCR) during a fear conditioning and extinction paradigm. For fMRI data analyses, we conducted region-specific and whole-brain analyses. We examined associations between beta weights from specific brain regions and CAPS scores. The group exposed to violent trauma showed significantly higher SCR during extinction recall. Those exposed to nonviolent trauma showed significantly higher functional activation during late extinction learning. The group exposed to violent trauma showed higher functional connectivity within the default mode network (DMN) and between the DMN and frontoparietal control network. For secondary analyses of sexual vs nonsexual trauma, we did not observe any between-group differences in SCR. During late extinction learning, the group exposed to sexual trauma showed significantly higher activation in the prefrontal cortex and precuneus. During extinction recall, the group exposed to nonsexual trauma showed significantly higher activation in the insular cortex. Violent trauma significantly impacts functional brain activations and connectivity in brain areas important for perception and attention with no significant impact on brain areas that modulate emotion regulation. Sexual trauma impacts brain areas important for internal perception.
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Epstein-Barr virus (EBV) infects more than 95% of adults worldwide and is closely associated with various malignancies. Considering the complex life cycle of EBV, developing vaccines targeting key entry glycoproteins to elicit robust and durable adaptive immune responses may provide better protection. EBV gHgL-, gB- and gp42-specific antibodies in healthy EBV carriers contributed to sera neutralizing abilities in vitro, indicating that they are potential antigen candidates. To enhance the immunogenicity of these antigens, we formulate three nanovaccines by co-delivering molecular adjuvants (CpG and MPLA) and antigens (gHgL, gB or gp42). These nanovaccines induce robust humoral and cellular responses through efficient activation of dendritic cells and germinal center response. Importantly, these nanovaccines generate high levels of neutralizing antibodies recognizing vulnerable sites of all three antigens. IgGs induced by a cocktail vaccine containing three nanovaccines confer superior protection from lethal EBV challenge in female humanized mice compared to IgG elicited by individual NP-gHgL, NP-gB and NP-gp42. Importantly, serum antibodies elicited by cocktail nanovaccine immunization confer durable protection against EBV-associated lymphoma. Overall, the cocktail nanovaccine shows robust immunogenicity and is a promising candidate for further clinical trials.
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Anticuerpos Neutralizantes , Anticuerpos Antivirales , Infecciones por Virus de Epstein-Barr , Glicoproteínas , Nanovacunas , Animales , Femenino , Humanos , Ratones , Adyuvantes Inmunológicos/administración & dosificación , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Infecciones por Virus de Epstein-Barr/inmunología , Infecciones por Virus de Epstein-Barr/prevención & control , Infecciones por Virus de Epstein-Barr/virología , Glicoproteínas/inmunología , Glicoproteínas/administración & dosificación , Herpesvirus Humano 4/inmunología , Linfoma/inmunología , Linfoma/virología , Nanovacunas/inmunologíaRESUMEN
Detecting and responding to threat engages several neural nodes including the amygdala, hippocampus, insular cortex, and medial prefrontal cortices. Recent propositions call for the integration of more distributed neural nodes that process sensory and cognitive facets related to threat. Integrative, sensitive, and reproducible distributed neural decoders for the detection and response to threat and safety have yet to be established. We combine functional MRI data across varying threat conditioning and negative affect paradigms from 1465 participants with multivariate pattern analysis to investigate distributed neural representations of threat and safety. The trained decoders sensitively and specifically distinguish between threat and safety cues across multiple datasets. We further show that many neural nodes dynamically shift representations between threat and safety. Our results establish reproducible decoders that integrate neural circuits, merging the well-characterized 'threat circuit' with sensory and cognitive nodes, discriminating threat from safety regardless of experimental designs or data acquisition parameters.
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Encéfalo , Miedo , Humanos , Miedo/fisiología , Amígdala del Cerebelo , Mapeo Encefálico , Señales (Psicología) , Imagen por Resonancia Magnética , Corteza Prefrontal/fisiologíaRESUMEN
BACKGROUND: The striatal-pallidal pathway plays an important role in cognitive control and modulation of behaviors. Globus pallidus interna (GPi), as a primary output structure, is crucial in modulating excitation and inhibition. Studies of GPi in psychiatric illnesses are lacking given the technical challenges of examining this small and functionally diverse subcortical structure. METHODS: 71 medication-naïve first episode schizophrenia (FES) participants and 73 healthy controls (HC) were recruited at the Shanghai Mental Health Center. Clinical symptoms and imaging data were collected at baseline and, in a subset of patients, 8 weeks after initiating treatment. Resting-state functional connectivity of sub-regions of the GP were assessed using a novel mask that combines two atlases to create 8 ROIs in the GP. RESULTS: Baseline imaging data from 63 FES patients and 55 HC met quality standards and were analyzed. FES patients exhibited less negative connectivity and increased positive connectivity between the right anterior GPi and several cortical and subcortical areas at baseline compared to HC (PFWE < 0.05). Positive functional connectivity between the right anterior GPi and several brain areas, including the right dorsal anterior cingulate gyrus, was associated with severity of positive symptoms (PFWE < 0.05) and predicted treatment response after 8 weeks (n = 28, adjusted R2 = 0.486, p < 0.001). CONCLUSIONS: Our results implicate striatal-pallidal-thalamic pathways in antipsychotic efficacy. If replicated, these findings may reflect failure of neurodevelopmental processes in adolescence and early adulthood that decrease functional connectivity as an index of failure of the limbic/associative GPi to appropriately inhibit irrelevant signals in psychosis.
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Esquizofrenia , Adolescente , Humanos , Adulto , Esquizofrenia/diagnóstico por imagen , Esquizofrenia/tratamiento farmacológico , Globo Pálido/diagnóstico por imagen , Mapeo Encefálico , Imagen por Resonancia Magnética/métodos , ChinaRESUMEN
Background: The subcellular organelle-targeting strategy has attracted wide attention for a variety of reasons, including strong specificity, high accuracy, low dose administration and few side effects. It is an important and challenging task to explore the multisubcellular organelle-targeting strategy to achieve effective tumor treatment. Materials & methods: Using bovine serum albumin as a nanoreactor, BSA/Cu/NQ/IR780/DOX nanoparticles (NPs) were constructed via drug-induced protein self-assembly. Folic acid was then coupled to the surface of NPs to prepare folate receptor-targeted FA-BSA/Cu/NQ/IR780/DOX NPs. Results & conclusion: The FA-BSA/Cu/NQ/IR780/DOX NPs exhibit multifunctional properties, including multisubcellular organelle-targeting, induction of response release in the tumor microenvironment, fluorescence imaging capabilities and potential for synergistic chemotherapy and photodynamic/photothermal tumor therapy.
The subcellular organelle-targeting strategy has attracted wide attention for a variety of reasons, including strong specificity, high accuracy, low dose administration and few side effects. Previous research has been mostly restricted to one or two subcellular organelle therapies. Despite promising results, the impact of these studies is limited by the hostile conditions of lysosomes, drug efflux facilitated by P-glycoprotein (P-gp), and the expression of antiapoptotic factors, all of which undermine the effectiveness of the treatments. Therefore, it is an important and challenging task to explore the multisubcellular organelle-targeting strategy to achieve effective tumor treatment. Herein, a versatile nanoparticle was designed and constructed to target multiple subcellular organelles, respond to stimuli in the tumor microenvironment, enable fluorescence imaging and facilitate synergistic chemotherapy and photodynamic/photothermal tumor therapy.
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Hipertermia Inducida , Nanopartículas , Neoplasias , Humanos , Fototerapia/métodos , Neoplasias/tratamiento farmacológico , Orgánulos , Doxorrubicina , Línea Celular Tumoral , Microambiente TumoralRESUMEN
The relationship between structural characteristics and extinction-induced brain activations in anxiety disorders (ANX) remains a space for greater exploration. In this study, we assessed gray matter volume (GMV) and its associated functional activations during fear extinction memory recall in an ANX cohort. We performed voxel-based morphometry analysis to examine GMVs from ANX (n = 92) and controls (n = 73). We further examined the correlation between GMVs and extinction-induced neural activations during recall across groups. In the patients' group, we observed decreased GMV in the anterior hippocampus and increased GMV in the dorsolateral prefrontal cortex (dlPFC). Hippocampal volume was positively correlated with ventromedial prefrontal cortex activation in healthy controls, while it was negatively correlated with dorsal anterior cingulate cortex (dACC) activation in ANX. The dlPFC volume was positively correlated with activations of dACC, pre- and post-central gyrus, and supramarginal gyrus only in healthy controls. Therefore, the link between structural and functional imbalance within the hippocampus and dlPFC might contribute to the pathophysiology of ANX. In the controls, the relationship between structural variance in the hippocampus and dlPFC and extinction-induced neural activations is consistent with a greater ability to regulate fear responding; associations that were absent in the ANX cohort. Furthermore, our findings of structure-function abnormalities within key nodes of emotional homeostasis in ANX point to dlPFC as a potential neural node to target using neuromodulation tools.
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Extinción Psicológica , Sustancia Gris , Humanos , Sustancia Gris/diagnóstico por imagen , Extinción Psicológica/fisiología , Miedo/fisiología , Imagen por Resonancia Magnética , Trastornos de Ansiedad/diagnóstico por imagenRESUMEN
Immunotherapy has been recognized as one of the most promising treatment strategies for head and neck squamous cell carcinoma (HNSCC). As a pioneering trend of immunotherapy, dendritic cell (DC) vaccines have displayed the ability to prime an immune response, while the insufficient immunogenicity and low lymph node (LN) targeting efficiency, resulted in an unsubstantiated therapeutic efficacy in clinical trials. Herein, a hybrid nanovaccine (Hy-M-Exo) is developed via fusing tumor-derived exosome (TEX) and dendritic cell membrane vesicle (DCMV). The hybrid nanovaccine inherited the key protein for lymphatic homing, CCR7, from DCMV and demonstrated an enhanced efficiency of LN targeting. Meanwhile, the reserved tumor antigens and endogenous danger signals in the hybrid nanovaccine activated antigen presenting cells (APCs) elicited a robust T-cell response. Moreover, the nanovaccine Hy-M-Exo displayed good therapeutic efficacy in a mouse model of HNSCC. These results indicated that Hy-M-Exo is of high clinical value to serve as a feasible strategy for antitumor immunotherapy.
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Neoplasias de Cabeza y Cuello , Vacunas , Ratones , Animales , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Receptores CCR7/metabolismo , Neoplasias de Cabeza y Cuello/terapia , Neoplasias de Cabeza y Cuello/metabolismo , Células Dendríticas , Ganglios Linfáticos , Vacunas/metabolismoRESUMEN
Tertiary lymphoid structures (TLSs) are formed in inflamed tissues, and recent studies demonstrated that the appearance of TLSs in tumor sites is associated with a good prognosis for tumor patients. However, the process of natural TLSs' formation was slow and uncontrollable. Herein, we developed a nanovaccine consisting of Epstein-Barr virus nuclear antigen 1 (EBNA1) and a bi-adjuvant of Mn2+ and cytosine-phosphate-guanine (CpG) formulated with tannic acid that significantly inhibited the development of mimicry nasopharyngeal carcinoma by fostering TLS formation. The nanovaccine activated LT-α and LT-ß pathways, subsequently enhancing the expression of downstream chemokines, CCL19/CCL21, CXCL10 and CXCL13, in the tumor microenvironment. In turn, normalized blood and lymph vessels were detected in the tumor tissues of the nanovaccine group, correlated with increased infiltration of lymphocytes. Especially, the proportion of the B220+ CD8+ T, which was produced via trogocytosis between T and B cells during activation of T cells, was increased in tumors of the nanovaccine group. Furthermore, the intratumoral effector memory T cells (Tem), CD45+, CD3+, CD8+, CD44+, and CD62L-, did not decrease after blocking the egress of T cells from tumor-draining lymph nodes by FTY-720. These results demonstrated that the nanovaccine can foster TLS formation, which thus enhances local immune responses significantly, delays tumor outgrowth, and prolongs the median survival time of murine models of mimicry nasopharyngeal carcinoma, demonstrating a promising strategy for nanovaccine development.
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Infecciones por Virus de Epstein-Barr , Neoplasias Nasofaríngeas , Estructuras Linfoides Terciarias , Humanos , Ratones , Animales , Estructuras Linfoides Terciarias/metabolismo , Estructuras Linfoides Terciarias/patología , Carcinoma Nasofaríngeo , Herpesvirus Humano 4 , Microambiente TumoralRESUMEN
Codelivering subunit antigens and Toll-like receptor (TLR) molecular adjuvants via nanocarriers can stimulate potent innate and specific immune responses. Simple and effective nanovaccines fabrication is crucial for application. However, most nanovaccines were fabricated by introducing additional delivery materials, increasing safety risk, cost and processing complexity. Herein, a carrier-free nanovaccine was facilely prepared using a TLR1/TLR2 adjuvant, Diprovocim, rich in benzene rings that could interact with aromatic residues in subunit antigens through π-π stacking without additional materials. The carrier-free nanovaccines with a narrow size distribution could target lymph nodes (LNs) after intravenous injection to mice. The carrier-free nanovaccines based on ovalbumin (OVA) can stimulate strong antibody titers and CD4+ and CD8+ T cell immune responses in mice, and it synergized with anti-PD1 showing a potent tumor suppression in B16F10-OVA tumor model of mice. Furthermore, the carrier-free nanovaccine with glycoprotein E (gE), a glycoprotein of the varicella-zoster virus (VZV), also showed potent humoral and cellular immune responses. Therefore, using subunit proteins to support Diprovocim by π-π stacking provides a new approach for the preparation and application of novel vaccines for tumor therapy and prevention of infectious diseases. STATEMENT OF SIGNIFICANCE: Codelivering subunit antigens and adjuvants via nanocarriers stimulate potent innate and specific immune responses. However, existing delivery materials for fabricating nanovaccines will inevitably increase the cost of preparation, controllability, process complexity and safety assessment. Therefore, this study easily prepared carrier-free nanovaccines using the benzene ring-rich TLR1/TLR2 adjuvant Diprovocim, which can interact with aromatic residues in subunit antigens via π-π stacking without additional materials. The carrier-free nanovaccines of OVA demonstrated a potent tumor inhibition in treating melanoma in combination with anti-PD1. And the nanovaccines of gE stimulated a strong antibody titer and cellular immune response for herpes zoster. Thus, the present study provides a new approach for the preparation of subunit vaccines to combat various cancers and virus infections.
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Nanopartículas , Neoplasias , Virosis , Animales , Ratones , Receptor Toll-Like 1 , Receptor Toll-Like 2 , Benceno , Inmunidad Celular , Adyuvantes Inmunológicos/química , Antígenos , Vacunas de Subunidad , Nanopartículas/químicaRESUMEN
Great efforts have been made to manipulate nanoparticles (NPs) with a diameter of 10-100 nm to passively target lymph nodes (LNs) to magnitude anti-tumor activity of T cells. However, no attention has been paid to increasing the retention of NPs with active affinity in order to induce a prolonged release of antigens or molecular adjuvants in the LNs mattering the immune response. Here, we formulated two NPs encapsulated with imiquimod (IMQ), a TLR7/8 agonist, and paclitaxel (PTX) and further modified them with tannic acid (TA), respectively, to generate IMQ NP and PTX NP with a final diameter of approximately 40 nm. Attributing a strong affinity of TA molecules to the elastin of LN conduits, the TA modified IMQ NPs can bypass the gaps in the layer of lymphatic endothelial cells and enter the paracortex through the lymph node capsule-associated (LNC) conduits. Similarly, the TA modified PTX NPs increased delivery of PTX to the metastatic tumor site in LNs, where the tumor-associated antigens were released and presented by conduits-lining dendritic cells to activate T cells. Thus, the NPs with deposition to LN conduits showed excellent performance in preventing lymphovascular invasion of triple-negative breast cancer cells and lung metastasis thereafter. On the contrary, the NPs without TA flowed through the subcutaneous sinus existing LNs directly by efferent lymphatic vessels showing relatively poor therapeutic outcomes. This study reveals that TA may mediate the long retention of antigens and molecular adjuvants to be delivered to deep LNs for developing potent vaccination technology.
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Vasos Linfáticos , Neoplasias , Humanos , Células Endoteliales , Ganglios Linfáticos , Paclitaxel/uso terapéutico , Neoplasias/patología , Antígenos de NeoplasiasRESUMEN
Findings pertaining to sex differences in the acquisition and extinction of threat conditioning, a paradigm widely used to study emotional homeostasis, remain inconsistent, particularly in humans. This inconsistency is likely due to multiple factors, one of which is sample size. Here, we pooled functional magnetic resonance imaging (fMRI) and skin conductance response (SCR) data from multiple studies in healthy humans to examine sex differences during threat conditioning, extinction learning, and extinction memory recall. We observed increased functional activation in males, relative to females, in multiple parietal and frontal (medial and lateral) cortical regions during acquisition of threat conditioning and extinction learning. Females mainly exhibited higher amygdala activation during extinction memory recall to the extinguished conditioned stimulus and also while responding to the unconditioned stimulus (presentation of the shock) during threat conditioning. Whole-brain functional connectivity analyses revealed that females showed increased connectivity across multiple networks including visual, ventral attention, and somatomotor networks during late extinction learning. At the psychophysiological level, a sex difference was only observed during shock delivery, with males exhibiting higher unconditioned responses relative to females. Our findings point to minimal to no sex differences in the expression of conditioned responses during acquisition and extinction of such responses. Functional MRI findings, however, show some distinct functional activations and connectivities between the sexes. These data suggest that males and females might use different neural mechanisms, mainly related to cognitive processing, to achieve comparable levels of acquired conditioned responses to threating cues.
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Condicionamiento Clásico , Extinción Psicológica , Amígdala del Cerebelo/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Condicionamiento Clásico/fisiología , Extinción Psicológica/fisiología , Femenino , Respuesta Galvánica de la Piel , Humanos , Imagen por Resonancia Magnética , MasculinoRESUMEN
Neural plasticity in subareas of the rodent amygdala is widely known to be essential for Pavlovian threat conditioning and safety learning. However, less consistent results have been observed in human neuroimaging studies. Here, we identify and test three important factors that may contribute to these discrepancies: the temporal profile of amygdala response in threat conditioning, the anatomical specificity of amygdala responses during threat conditioning and safety learning, and insufficient power to identify these responses. We combined data across multiple studies using a well-validated human threat conditioning paradigm to examine amygdala involvement during threat conditioning and safety learning. In 601 humans, we show that two amygdala subregions tracked the conditioned stimulus with aversive shock during early conditioning while only one demonstrated delayed responding to a stimulus not paired with shock. Our findings identify cross-species similarities in temporal- and anatomical-specific amygdala contributions to threat and safety learning, affirm human amygdala involvement in associative learning and highlight important factors for future associative learning research in humans.
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Amígdala del Cerebelo , Condicionamiento Clásico , Miedo , Amígdala del Cerebelo/fisiología , Condicionamiento Clásico/fisiología , Miedo/fisiología , Humanos , Plasticidad NeuronalRESUMEN
Examining the neural circuits of fear/threat extinction advanced our mechanistic understanding of several psychiatric disorders, including anxiety disorders (AX) and posttraumatic stress disorder (PTSD). More is needed to understand the interplay of large-scale neural networks during fear extinction in these disorders. We used dynamic functional connectivity (FC) to study how FC might be perturbed during conditioned fear extinction in individuals with AX or PTSD. We analyzed neuroimaging data from 338 individuals that underwent a two-day fear conditioning and extinction paradigm. The sample included healthy controls (HC), trauma-exposed non-PTSD controls, and patients diagnosed with AX or PTSD. Dynamic FC during extinction learning gradually increased in the HC group but not in patient groups. The lack of FC change in patients was predominantly observed within and between the default mode, frontoparietal control, and somatomotor networks. The AX and PTSD groups showed impairments in different, yet partially overlapping connections especially involving the dorsolateral prefrontal cortex. Extinction-induced FC predicted ventromedial prefrontal cortex activation and FC during extinction memory recall only in the HC group. FC impairments during extinction learning correlated with fear- and anxiety-related clinical measures. These findings suggest that relative to controls, individuals with AX or PTSD exhibited widespread abnormal FC in higher-order cognitive and attention networks during extinction learning and failed to establish a link between neural signatures during extinction learning and memory retrieval. This failure might underlie abnormal processes related to the conscious awareness, attention allocation, and sensory processes during extinction learning and retrieval in fear- and anxiety-related disorders.
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Miedo , Trastornos por Estrés Postraumático , Trastornos de Ansiedad , Condicionamiento Clásico/fisiología , Extinción Psicológica/fisiología , Miedo/fisiología , Humanos , Imagen por Resonancia Magnética/métodosRESUMEN
Prostate cancer is the most common malignancy and the second leading cause of cancer-induced death among men. Recently, photodynamic therapy (PDT) has attracted great attention in prostate cancer treatment because of its high accuracy and no trauma. However, the hypoxic microenvironment of the tumor severely reduces the therapeutic efficacy of oxygen-dependent PDT in prostate cancer, which hampers the generation of reactive oxygen species (ROS). In addition, the PDT process induces the overexpression of pro-survival and anti-apoptotic proteins, thereby reducing the efficacy of PDT. This study proposed a novel multifunctional nanosystem for the targeted delivery of indocyanine green (ICG), 2,2'-azobis[2-(2-imidazolinI-2-yl) propane] dihydrochloride (AIBI), and heat shock protein 90 (Hsp90) inhibitor geldanamycin (17-AAG). Under near-infrared light irradiation, the photothermal effect of ICG induces AIBI decomposition and releases oxygen-independent free radicals, which rescues the hindered ICG-mediated ROS generation. Moreover, 17-AAG reduces heat resistance by inhibiting Hsp90, thereby achieving mild hyperthermia. Simultaneously, the inhibition of Hsp90 can inhibit the overexpression of its client proteins such as anti-apoptotic proteins (survivin) and androgen receptor (AR), thereby improving the efficacy of PDT and inducing prostate cancer cell apoptosis. Results show that the nanosystem enhances PDT by combining free radicals and 17-AAG, exhibiting a good anticancer effect on prostate cancer cells but less toxicity on normal cells.
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Antineoplásicos , Hipertermia Inducida , Fotoquimioterapia , Neoplasias de la Próstata , Antineoplásicos/farmacología , Benzoquinonas , Línea Celular Tumoral , Radicales Libres , Proteínas HSP90 de Choque Térmico , Humanos , Hipertermia Inducida/métodos , Verde de Indocianina/farmacología , Verde de Indocianina/uso terapéutico , Lactamas Macrocíclicas , Masculino , Oxígeno , Fotoquimioterapia/métodos , Neoplasias de la Próstata/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Microambiente TumoralRESUMEN
Autism spectrum disorder (ASD) is a specific brain disease that causes communication impairments and restricted interests. Functional connectivity analysis methodology is widely used in neuroscience research and shows much potential in discriminating ASD patients from healthy controls. However, due to heterogeneity of ASD patients, the performance of conventional functional connectivity classification methods is relatively poor. Graph neural network is an effective graph representation method to model structured data like functional connectivity. In this paper, we proposed a functional graph discriminative network (FGDN) for ASD classification. On the basis of pre-built graph templates, the proposed FGDN is able to effectively distinguish ASD patient from health controls. Moreover, we studied the size of training set for effective training, inter-site predictions, and discriminative brain regions. Discriminative brain regions were determined by the proposed model to investigate its applicability and biomarkers for ASD identification. For functional connectivity classification and analysis, FGDN is not only an effective tool for ASD identification but also a potential technique in neuroscience research.
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Fluctuations of endogenous estrogen modulates fear extinction, but the influence of exogenous estradiol is less studied. Moreover, little focus has been placed on the impact of estradiol on broad network connectivity beyond the fear extinction circuit. Here, we examined the effect of acute exogenous estradiol administration on fear extinction-induced brain activation, whole-brain functional connectivity (FC) during the fear extinction task and post-extinction resting-state. Ninety healthy women (57 using oral contraceptives [OC], 33 naturally cycling [NC]) were fear conditioned on day 1. They ingested an estradiol or placebo pill prior to extinction learning on day 2 (double-blind design). Extinction memory was assessed on day 3. Task-based functional MRI data were ascertained on days 2 and 3 and resting-state data were collected post-extinction on day 2 and pre-recall on day 3. Estradiol administration significantly modulated the neural signature associated with fear extinction learning and memory, consistent with prior studies. Importantly, estradiol administration induced significant changes in FC within multiple networks, including the default mode and somatomotor networks during extinction learning, post-extinction, and during extinction memory recall. Exploratory analyses revealed that estradiol impacted ventromedial prefrontal cortex (vmPFC) activation and FC differently in the NC and OC women. The data implicate a more diffused and significant effect of acute estradiol administration on multiple networks. Such an effect might be beneficial to modulating attention and conscious processes in addition to engaging neural processes associated with emotional learning and memory consolidation.
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Estradiol , Extinción Psicológica , Estradiol/farmacología , Estrógenos , Miedo , Femenino , Humanos , Imagen por Resonancia Magnética , Recuerdo Mental , Corteza PrefrontalRESUMEN
Exploring the neural circuits of the extinction of conditioned fear is critical to advance our understanding of fear- and anxiety-related disorders. The field has focused on examining the role of various regions of the medial prefrontal cortex, insular cortex, hippocampus, and amygdala in conditioned fear and its extinction. The contribution of this 'fear network' to the conscious awareness of fear has recently been questioned. And as such, there is a need to examine higher/multiple cortical systems that might contribute to the conscious feeling of fear and anxiety. Herein, we studied functional connectivity patterns across the entire brain to examine the contribution of multiple networks to the acquisition of fear extinction learning and its retrieval. We conducted trial-by-trial analyses on data from 137 healthy participants who underwent a two-day fear conditioning and extinction paradigm in a functional magnetic resonance imaging (fMRI) scanner. We found that functional connectivity across a broad range of brain regions, many of which are part of the default mode, frontoparietal, and ventral attention networks, increased from early to late extinction learning only to a conditioned cue. The increased connectivity during extinction learning predicted the magnitude of extinction memory tested 24 h later. Together, these findings provide evidence supporting recent studies implicating distributed brain regions in learning, consolidation and expression of fear extinction memory in the human brain.
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Encéfalo/diagnóstico por imagen , Extinción Psicológica/fisiología , Miedo/fisiología , Aprendizaje/fisiología , Red Nerviosa/diagnóstico por imagen , Plasticidad Neuronal/fisiología , Adulto , Encéfalo/fisiología , Mapeo Encefálico , Condicionamiento Psicológico/fisiología , Femenino , Respuesta Galvánica de la Piel/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/fisiologíaRESUMEN
The proangiogenic protein, survivin, is a client protein for heat shock protein 90 (Hsp-90), whose overexpression is induced by photodynamic therapy (PDT), leading to the inhibition of capase-9 and the blockage of apoptosis. The overexpression of Hsp-90 in cancer cells can rapidly acquire thermoresistance during photothermal therapy (PTT), leading to insufficient apoptosis, increased cell viability, and tumor recurrence. A potential approach to block the PTT-induced overexpression of Hsp-90 and the overexpression of survivin is developed by using an Hsp-90 inhibitor and anticancer agent, namely, geldanamycin (GM). These inhibitors also develop a mild-temperature PTT strategy to reach synergistic PDT and PTT efficiency. Thus, Cy7-SQ is designed by a covalent disulfide linkage between a photothermal agent (i.e., canine dye 7 [Cy7]) and a photosensitizer (i.e., squaraine dye [SQ]) for the improved photostability and thermal stability of Cy7 and SQ. The cleavage of the Cy7-SQ linkage by glutathione in a tumor microenvironment increases the efficiency of synergistic PDT and PTT. In the current study, bovine serum albumin (BSA)/Cy7-SQ/GM nanoparticles are developed through the self-assembly of BSA, Cy7-SQ, and GM to accelerate the apoptosis of cancer cells via near-infrared (NIR) laser irradiation, thus realizing Hsp-90-regulated synergistic PDT/PTT combined with chemotherapy.
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Antineoplásicos , Nanopartículas , Fotoquimioterapia , Animales , Colorantes , Perros , Proteínas de Choque Térmico , Fototerapia , Albúmina Sérica BovinaRESUMEN
Effective targeting and in situ imaging-guided treatment are particularly important for accurate clinical photodynamic therapy (PDT) of malignant tumors. Herein, we propose a single molecule, named IMC-DAH-SQ, which possesses dual-targeting components, including structure-inherent targeting (SIT) and cyclooxygenase-2 (COX-2) targeting units, and controllable turn-on near infrared (NIR) fluorescence. Due to its amphiphilicity, IMC-DAH-SQ assembles into a nanoprobe with low background fluorescence. After incubation with tumor cells, the SIT and COX-2 recognition characteristics of IMC-DAH-SQ endow it with preferential tumor-targeting activity. The strong binding with overexpressed COX-2 can collapse the nanoprobe to monomers after accumulation in tumor cells, leading to turn-on NIR fluorescence that is completely different from normal cells. Additionally, benefiting from the single molecular model tactic, the nanoprobe has the advantages of simple synthesis without ever considering the loading rate and separation between the photosensitizer and targeting unit. Other favorite features, including superior biocompatibility, weak dark toxicity, and mitochondria enrichment capability, are implemented. All these traits not only afford nanoprobe precision tumor cell targeting capability but also provide promising imaging-guided antitumor therapy. We believe that the single molecular protocol will establish a novel strategy for simultaneous diagnosis and anticancer medicine treatment utilizing versatile but small compounds.
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Ciclooxigenasa 2/metabolismo , Fluorescencia , Regulación Neoplásica de la Expresión Génica , Nanoestructuras/química , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , HumanosRESUMEN
Translational models of fear conditioning and extinction have elucidated a core neural network involved in the learning, consolidation, and expression of conditioned fear and its extinction. Anxious or trauma-exposed brains are characterized by dysregulated neural activations within regions of this fear network. In this study, we examined how the functional MRI activations of 10 brain regions commonly activated during fear conditioning and extinction might distinguish anxious or trauma-exposed brains from controls. To achieve this, activations during four phases of a fear conditioning and extinction paradigm in 304 participants with or without a psychiatric diagnosis were studied. By training convolutional neural networks (CNNs) using task-specific brain activations, we reliably distinguished the anxious and trauma-exposed brains from controls. The performance of models decreased significantly when we trained our CNN using activations from task-irrelevant brain regions or from a brain network that is irrelevant to fear. Our results suggest that neuroimaging data analytics of task-induced brain activations within the fear network might provide novel prospects for development of brain-based psychiatric diagnosis.