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1.
J Neurosci ; 44(26)2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38664013

RESUMEN

The periaqueductal gray (PAG) is a small midbrain structure that surrounds the cerebral aqueduct, regulates brain-body communication, and is often studied for its role in "fight-or-flight" and "freezing" responses to threat. We used ultra-high-field 7 T fMRI to resolve the PAG in humans and distinguish it from the cerebral aqueduct, examining its in vivo function during a working memory task (N = 87). Both mild and moderate cognitive demands elicited spatially similar patterns of whole-brain blood oxygenation level-dependent (BOLD) response, and moderate cognitive demand elicited widespread BOLD increases above baseline in the brainstem. Notably, these brainstem increases were not significantly greater than those in the mild demand condition, suggesting that a subthreshold brainstem BOLD increase occurred for mild cognitive demand as well. Subject-specific masks were group aligned to examine PAG response. In PAG, both mild and moderate demands elicited a well-defined response in ventrolateral PAG, a region thought to be functionally related to anticipated painful threat in humans and nonhuman animals-yet, the present task posed only the most minimal (if any) "threat," with the cognitive tasks used being approximately as challenging as remembering a phone number. These findings suggest that the PAG may play a more general role in visceromotor regulation, even in the absence of threat.


Asunto(s)
Imagen por Resonancia Magnética , Memoria a Corto Plazo , Sustancia Gris Periacueductal , Humanos , Sustancia Gris Periacueductal/fisiología , Masculino , Femenino , Memoria a Corto Plazo/fisiología , Adulto , Imagen por Resonancia Magnética/métodos , Adulto Joven , Mapeo Encefálico
2.
Nano Lett ; 24(23): 7055-7062, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38810105

RESUMEN

Transparent passive cooling materials can cool targets environmentally without interfering with light transmission or visual information reception. They play a prominent role in solar cells and flexible display cooling. However, achieving potent transparent cooling remains challenging, because light transmission is accompanied by thermal energy. Here we propose to realize effective passive cooling in transparent materials via a microscale phase separation hydrogel film. The poly(N-isopropylacrylamide-co-acrylamide) hydrogel presents light transmittance of >96% and infrared emissivity as high as 95%. The microphase-separated structure affords a higher enthalpy of evaporation. The film is highly adhesive. In field applications, it reduces temperatures by 9.14 °C compared to those with uncovered photovoltaic panels and 7.68 °C compared to those for bare flexible light-emitting diode screens. Simulations indicate that energy savings of 32.76-51.65 MJ m-2 year-1 can be achieved in typical tropical monsoon climates and temperate continental climates. We expect this work to contribute to energy-efficient materials and a carbon-neutral society.

3.
Mol Psychiatry ; 28(6): 2540-2548, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36991135

RESUMEN

Adolescents experience alarmingly high rates of major depressive disorder (MDD), however, gold-standard treatments are only effective for ~50% of youth. Accordingly, there is a critical need to develop novel interventions, particularly ones that target neural mechanisms believed to potentiate depressive symptoms. Directly addressing this gap, we developed mindfulness-based fMRI neurofeedback (mbNF) for adolescents that aims to reduce default mode network (DMN) hyperconnectivity, which has been implicated in the onset and maintenance of MDD. In this proof-of-concept study, adolescents (n = 9) with a lifetime history of depression and/or anxiety were administered clinical interviews and self-report questionnaires, and each participant's DMN and central executive network (CEN) were personalized using a resting state fMRI localizer. After the localizer scan, adolescents completed a brief mindfulness training followed by a mbNF session in the scanner wherein they were instructed to volitionally reduce DMN relative to CEN activation by practicing mindfulness meditation. Several promising findings emerged. First, mbNF successfully engaged the target brain state during neurofeedback; participants spent more time in the target state with DMN activation lower than CEN activation. Second, in each of the nine adolescents, mbNF led to significantly reduced within-DMN connectivity, which correlated with post-mbNF increases in state mindfulness. Last, a reduction of within-DMN connectivity mediated the association between better mbNF performance and increased state mindfulness. These findings demonstrate that personalized mbNF can effectively and non-invasively modulate the intrinsic networks associated with the emergence and persistence of depressive symptoms during adolescence.


Asunto(s)
Trastorno Depresivo Mayor , Atención Plena , Neurorretroalimentación , Humanos , Adolescente , Trastorno Depresivo Mayor/terapia , Proyectos Piloto , Imagen por Resonancia Magnética , Red en Modo Predeterminado , Encéfalo/fisiología , Mapeo Encefálico , Vías Nerviosas/fisiología
4.
Bioorg Chem ; 151: 107675, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39126868

RESUMEN

Rho-associated coiled-coil kinase (ROCK) is involved in multiple cellular activities regulating the actin cytoskeleton, such as cell morphology, adhesion, and migration. The inhibition of ROCK is a feasible strategy to suppress breast cancer metastasis. Herein, based on Belumosudil, a series of pyrazolo[1,5-a]pyrimidine derivatives as selective ROCK2 inhibitors were designed and synthesized. Through systematic investigation of SARs, the piperazine analog 7u was identified with optimum ROCK2 inhibitory activity (IC50 = 36.8 nM) and excellent selectivity over the isoform protein ROCK1 (>250-fold). Intriguingly, upon treatment with 7u, the arrangement of the MDA-MB-231 cytoskeleton was affected accompanied by the alteration of morphology. Furthermore, cell scratch and transwell assays indicated that 7u inhibited MDA-MB-231 cell migration and invasion in a dose-dependent manner. Ultimately, the binding model of 7u with ROCK2 well accounted for the superior activities of 7u as a promising ROCK2 inhibitor with the potential application in breast cancer metastasis treatment.


Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Movimiento Celular , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Inhibidores de Proteínas Quinasas , Pirazoles , Pirimidinas , Quinasas Asociadas a rho , Humanos , Quinasas Asociadas a rho/antagonistas & inhibidores , Quinasas Asociadas a rho/metabolismo , Movimiento Celular/efectos de los fármacos , Pirimidinas/farmacología , Pirimidinas/química , Pirimidinas/síntesis química , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/síntesis química , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Relación Estructura-Actividad , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/síntesis química , Femenino , Pirazoles/farmacología , Pirazoles/química , Pirazoles/síntesis química , Estructura Molecular , Proliferación Celular/efectos de los fármacos , Línea Celular Tumoral , Descubrimiento de Drogas , Simulación del Acoplamiento Molecular
5.
Cereb Cortex ; 33(10): 6028-6037, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-36520501

RESUMEN

Recollection of past events has been associated with the core recollection network comprising the posterior medial temporal lobe and parietal regions, as well as the medial prefrontal cortex (mPFC). The development of the brain basis for recollection is understudied. In a sample of adults (n = 22; 18-25 years) and children (n = 23; 9-13 years), the present study aimed to address this knowledge gap using a cued recall paradigm, known to elicit recollection experience. Successful recall was associated with activations in regions of the core recollection network and frontoparietal network. Adults exhibited greater successful recall activations compared with children in the precuneus and right angular gyrus. In contrast, similar levels of successful recall activations were observed in both age groups in the mPFC. Group differences were also seen in the hippocampus and lateral frontal regions. These findings suggest that the engagement of the mPFC in episodic retrieval may be relatively early maturing, whereas the contribution to episodic retrieval of more posterior regions such as the precuneus and angular gyrus undergoes more protracted maturation.


Asunto(s)
Mapeo Encefálico , Imagen por Resonancia Magnética , Adulto , Niño , Humanos , Recuerdo Mental , Encéfalo/diagnóstico por imagen , Lóbulo Parietal
6.
Neuroimage ; 268: 119879, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36642154

RESUMEN

Thirty years of neuroimaging reveal the set of brain regions consistently associated with pleasant and unpleasant affect in humans-or the neural reference space for valence. Yet some of humans' most potent affective states occur in the context of other humans. Prior work has yet to differentiate how the neural reference space for valence varies as a product of the sociality of affective stimuli. To address this question, we meta-analyzed across 614 social and non-social affective neuroimaging contrasts, summarizing the brain regions that are consistently activated for social and non-social affective information. We demonstrate that across the literature, social and non-social affective stimuli yield overlapping activations within regions associated with visceromotor control, including the amygdala, hypothalamus, anterior cingulate cortex and insula. However, we find that social processing differs from non-social affective processing in that it involves additional cortical activations in the medial prefrontal and posterior cingulum that have been associated with mentalizing and prediction. A Bayesian classifier was able to differentiate unpleasant from pleasant affect, but not social from non-social affective states. Moreover, it was not able to classify unpleasantness from pleasantness at the highest levels of sociality. These findings suggest that highly social scenarios may be equally salient to humans, regardless of their valence.


Asunto(s)
Mapeo Encefálico , Encéfalo , Humanos , Teorema de Bayes , Mapeo Encefálico/métodos , Encéfalo/diagnóstico por imagen , Emociones , Conducta Social , Imagen por Resonancia Magnética/métodos
7.
Opt Lett ; 48(22): 5935-5938, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37966756

RESUMEN

We present the design and fabrication of an on-chip FBG interrogator based on arrayed waveguide grating (AWG) technology. The spectral overlap between adjacent channels in the integrated AWG is significantly enhanced through a combination approach involving the reduction of the output waveguide spacing and an increase in the input waveguide width. As a result of these design choices, our AWG demonstrates excellent spectral consistency, with spectral cross talk exceeding 30 dB. The interrogator seamlessly combining optical and circuitry components achieves full integration and enables a wide range of interrogation wavelengths, including C-band and L-band. With an interrogation range extending up to 80 nm, it theoretically has the capacity to simultaneously interrogate the wavelengths of 20 FBG sensors. Experimental findings demonstrate an absolute interrogation accuracy of less than 2 pm for the fully integrated interrogator. With its compact size, cost-effectiveness, exceptional precision, and ease of integration, the proposed interrogator holds a substantial promise for widespread application in the realm of FBG sensing.

8.
BMC Psychiatry ; 23(1): 757, 2023 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-37848857

RESUMEN

BACKGROUND: Adolescence is characterized by a heightened vulnerability for Major Depressive Disorder (MDD) onset, and currently, treatments are only effective for roughly half of adolescents with MDD. Accordingly, novel interventions are urgently needed. This study aims to establish mindfulness-based real-time fMRI neurofeedback (mbNF) as a non-invasive approach to downregulate the default mode network (DMN) in order to decrease ruminatory processes and depressive symptoms. METHODS: Adolescents (N = 90) with a current diagnosis of MDD ages 13-18-years-old will be randomized in a parallel group, two-arm, superiority trial to receive either 15 or 30 min of mbNF with a 1:1 allocation ratio. Real-time neurofeedback based on activation of the frontoparietal network (FPN) relative to the DMN will be displayed to participants via the movement of a ball on a computer screen while participants practice mindfulness in the scanner. We hypothesize that within-DMN (medial prefrontal cortex [mPFC] with posterior cingulate cortex [PCC]) functional connectivity will be reduced following mbNF (Aim 1: Target Engagement). Additionally, we hypothesize that participants in the 30-min mbNF condition will show greater reductions in within-DMN functional connectivity (Aim 2: Dosing Impact on Target Engagement). Aim 1 will analyze data from all participants as a single-group, and Aim 2 will leverage the randomized assignment to analyze data as a parallel-group trial. Secondary analyses will probe changes in depressive symptoms and rumination. DISCUSSION: Results of this study will determine whether mbNF reduces functional connectivity within the DMN among adolescents with MDD, and critically, will identify the optimal dosing with respect to DMN modulation as well as reduction in depressive symptoms and rumination. TRIAL REGISTRATION: This study has been registered with clinicaltrials.gov, most recently updated on July 6, 2023 (trial identifier: NCT05617495).


Asunto(s)
Trastorno Depresivo Mayor , Atención Plena , Neurorretroalimentación , Humanos , Adolescente , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/terapia , Imagen por Resonancia Magnética/métodos , Neurorretroalimentación/métodos , Giro del Cíngulo/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos
9.
Toxicol Appl Pharmacol ; 444: 116020, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35430233

RESUMEN

Titanium dioxide often enters the respiratory tract in the form of nano-dust in occupational sites. Metabolomics may be a promising method for studying the toxicology of nano titanium dioxide. The intention of this study was to explore the possible impact of titanium dioxide nanoparticles (TiO2 NPs) on the metabolomics signatures of human normal bronchial epithelial (BEAS-2B) cells and to search for investigate the role of reactive oxygen species (ROS). In this study, BEAS-2B cells were treated by TiO2 NPs (0, 25, 50 and 100 µg/mL) for 48 h. The metabolites extracted from BEAS-2B cells were determined by untargeted metabolomics technique, and the differential metabolites and metabolic pathways were discovered by using multivariate analysis. Intracellular ROS was detected by DCFH-DA probe and flow cytometry method. Machine learning was used to explore the relationship between ROS and metabolomics changes. Totally, seventy-six differential metabolites and the steroid biosynthesis pathway of BEAS-2B cells were observed after treatment of TiO2 NPs. Lipid and lipid-like metabolites were the most significant classes among the metabolite products induced by TiO2 NPs. TiO2 NPs resulted in a dose-dependent increase in intracellular ROS levels, and correlated with most of the differential metabolites. In conclusion, TiO2 NPs increased the level of the oxidative stress, which could contribute to the altered signature represented by lipid metabolism in BEAS-2B cells.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Humanos , Lípidos , Metabolómica , Nanopartículas del Metal/toxicidad , Nanopartículas/toxicidad , Estrés Oxidativo , Especies Reactivas de Oxígeno/metabolismo , Titanio/toxicidad
10.
Int J Med Sci ; 19(4): 701-710, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35582421

RESUMEN

Wnt signaling is relevant for a wide range of biological processes, including reproductive function. The function of Wnt10a in female fertility, however, remains obscure. In the present study, we explored the structure and function of the female reproductive organs in Wnt10a knockout (KO) mice. The expression of ß-catenin signaling was significantly lower in the ovaries of the Wnt10a KO mice compared with wild-type (WT) mice. In addition, the estrous cycles were disrupted, ovarian follicles were diminished, and endometria were thinner, accompanied by lower serum estrogen levels, and higher testosterone and progesterone levels in Wnt10a KO mice. The expression of the ovarian cytochrome P450 family 19 subfamily A member 1 (Cyp19a1) was significantly lower in Wnt10a KO mice. We detected no significant changes in the levels of the gonadotropins between WT and KO mice. Together, our findings indicate that deficiency of Wnt10a causes female infertility through ß-catenin and Cyp19a1signaling pathways in mice.


Asunto(s)
Infertilidad Femenina , Proteínas Wnt , beta Catenina , Animales , Aromatasa/genética , Aromatasa/metabolismo , Femenino , Humanos , Infertilidad Femenina/genética , Ratones , Ratones Noqueados , Proteínas del Tejido Nervioso/metabolismo , Ovario , Proteínas Wnt/genética , Vía de Señalización Wnt , beta Catenina/genética , beta Catenina/metabolismo
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