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1.
Proc Natl Acad Sci U S A ; 121(12): e2322677121, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38466841

RESUMEN

The spindle assembly checkpoint (SAC) ensures faithful chromosome segregation during cell division by monitoring kinetochore-microtubule attachment. Plants produce both sequence-conserved and diverged SAC components, and it has been largely unknown how SAC activation leads to the assembly of these proteins at unattached kinetochores to prevent cells from entering anaphase. In Arabidopsis thaliana, the noncanonical BUB3.3 protein was detected at kinetochores throughout mitosis, unlike MAD1 and the plant-specific BUB1/MAD3 family protein BMF3 that associated with unattached chromosomes only. When BUB3.3 was lost by a genetic mutation, mitotic cells often entered anaphase with misaligned chromosomes and presented lagging chromosomes after they were challenged by low doses of the microtubule depolymerizing agent oryzalin, resulting in the formation of micronuclei. Surprisingly, BUB3.3 was not required for the kinetochore localization of other SAC proteins or vice versa. Instead, BUB3.3 specifically bound to BMF3 through two internal repeat motifs that were not required for BMF3 kinetochore localization. This interaction enabled BMF3 to recruit CDC20, a downstream SAC target, to unattached kinetochores. Taken together, our findings demonstrate that plant SAC utilizes unconventional protein interactions for arresting mitosis, with BUB3.3 directing BMF3's role in CDC20 recruitment, rather than the recruitment of BUB1/MAD3 proteins observed in fungi and animals. This distinct mechanism highlights how plants adapted divergent versions of conserved cell cycle machinery to achieve specialized SAC control.


Asunto(s)
Arabidopsis , Cinetocoros , Animales , Cinetocoros/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Puntos de Control de la Fase M del Ciclo Celular/genética , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Puntos de Control del Ciclo Celular , Huso Acromático/metabolismo
2.
Nat Chem Biol ; 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448735

RESUMEN

Synthetic signaling receptors enable programmable cellular responses coupling with customized inputs. However, engineering a designer force-sensing receptor to rewire mechanotransduction remains largely unexplored. Herein, we introduce nongenetically engineered artificial mechanoreceptors (AMRs) capable of reprogramming non-mechanoresponsive receptor tyrosine kinases (RTKs) to sense user-defined force cues, enabling de novo-designed mechanotransduction. AMR is a modular DNA-protein chimera comprising a mechanosensing-and-transmitting DNA nanodevice grafted on natural RTKs via aptameric anchors. AMR senses intercellular tensile force via an allosteric DNA mechano-switch with tunable piconewton-sensitive force tolerance, actuating a force-triggered dynamic DNA assembly to manipulate RTK dimerization and activate intracellular signaling. By swapping the force-reception ligands, we demonstrate the AMR-mediated activation of c-Met, a representative RTK, in response to the cellular tensile forces mediated by cell-adhesion proteins (integrin, E-cadherin) or membrane protein endocytosis (CI-M6PR). Moreover, AMR also allows the reprogramming of FGFR1, another RTK, to customize mechanobiological function, for example, adhesion-mediated neural stem cell maintenance.

3.
Plant J ; 118(3): 905-919, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38251949

RESUMEN

Phosphate (Pi) is essential for plant growth and development. One strategy to improve Pi use efficiency is to enhance Pi remobilization among leaves. Using transcriptome analysis with first (top) and fourth (down) leaf blades from rice (Oryza sativa) in Pi-sufficient and deficient conditions, we identified 1384 genes differentially expressed among these leaf blades. These genes were involved in physiological processes, metabolism, transport, and photosynthesis. Moreover, we identified the Pi efflux transporter gene, OsPHO1;3, responding to Pi-supplied conditions among these leaf blades. OsPHO1;3 is highly expressed in companion cells of phloem, but not xylem, in leaf blades and induced by Pi starvation. Mutation of OsPHO1;3 led to Pi accumulation in second to fourth leaves under Pi-sufficient conditions, but enhanced Pi levels in first leaves under Pi-deficient conditions. These Pi accumulations in leaves of Ospho1;3 mutants resulted from induction of OsPHT1;2 and OsPHT1;8 in root and reduction of Pi remobilization in leaf blades, revealed by the decreased Pi in phloem of leaves. Importantly, lack of OsPHO1;3 caused growth defects under a range of Pi-supplied conditions. These results demonstrate that Pi remobilization is essential for Pi homeostasis and plant growth irrespective of Pi-supplied conditions, and OsPHO1;3 plays an essential role in Pi remobilization for normal plant growth.


Asunto(s)
Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Homeostasis , Oryza , Floema , Proteínas de Transporte de Fosfato , Fosfatos , Hojas de la Planta , Proteínas de Plantas , Oryza/genética , Oryza/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/genética , Fosfatos/metabolismo , Floema/metabolismo , Floema/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Mutación , Transcriptoma
4.
Proc Natl Acad Sci U S A ; 119(44): e2209565119, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36306331

RESUMEN

Efferent neurons are believed to play essential roles in maintaining auditory function. The lateral olivocochlear (LOC) neurons-which project from the brainstem to the inner ear, where they release multiple transmitters including peptides, catecholamines, and acetylcholine-are the most numerous yet least understood elements of efferent control of the cochlea. Using in vitro calcium imaging and patch-clamp recordings, we found that LOC neurons in juvenile and young adult mice exhibited extremely slow waves of activity (∼0.1 Hz). These seconds-long bursts of Na+ spikes were driven by an intrinsic oscillator dependent on L-type Ca2+ channels and were not observed in prehearing mice, suggesting an age-dependent mechanism underlying the intrinsic oscillator. Using optogenetic approaches, we identified both ascending (T-stellate cells of the cochlear nucleus) and descending (auditory cortex) sources of synaptic excitation, as well as the synaptic receptors used for such excitation. Additionally, we identified potent inhibition originating in the glycinergic medial nucleus of trapezoid body (MNTB). Conductance-clamp experiments revealed an unusual mechanism of electrical signaling in LOC neurons, in which synaptic excitation and inhibition served to switch on and off the intrinsically generated spike burst mechanism, allowing for prolonged periods of activity or silence controlled by brief synaptic events. Protracted bursts of action potentials may be essential for effective exocytosis of the diverse transmitters released by LOC fibers in the cochlea.


Asunto(s)
Núcleo Coclear , Cuerpo Trapezoide , Ratones , Animales , Núcleo Coclear/fisiología , Cóclea/fisiología , Cuerpo Trapezoide/fisiología , Neuronas/fisiología , Potenciales de Acción/fisiología
5.
J Biol Chem ; 299(4): 103045, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36822326

RESUMEN

Glucose-stimulated insulin secretion of pancreatic ß cells is essential in maintaining glucose homeostasis. Recent evidence suggests that the Nephrin-mediated intercellular junction between ß cells is implicated in the regulation of insulin secretion. However, the underlying mechanisms are only partially characterized. Herein we report that GIV is a signaling mediator coordinating glucose-stimulated Nephrin phosphorylation and endocytosis with insulin secretion. We demonstrate that GIV is expressed in mouse islets and cultured ß cells. The loss of function study suggests that GIV is essential for the second phase of glucose-stimulated insulin secretion. Next, we demonstrate that GIV mediates the high glucose-stimulated tyrosine phosphorylation of GIV and Nephrin by recruiting Src kinase, which leads to the endocytosis of Nephrin. Subsequently, the glucose-induced GIV/Nephrin/Src signaling events trigger downstream Akt phosphorylation, which activates Rac1-mediated cytoskeleton reorganization, allowing insulin secretory granules to access the plasma membrane for the second-phase secretion. Finally, we found that GIV is downregulated in the islets isolated from diabetic mice, and rescue of GIV ameliorates the ß-cell dysfunction to restore the glucose-stimulated insulin secretion. We conclude that the GIV/Nephrin/Akt signaling axis is vital to regulate glucose-stimulated insulin secretion. This mechanism might be further targeted for therapeutic intervention of diabetic mellitus.


Asunto(s)
Diabetes Mellitus Experimental , Células Secretoras de Insulina , Islotes Pancreáticos , Animales , Ratones , Diabetes Mellitus Experimental/metabolismo , Glucosa/metabolismo , Insulina/metabolismo , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Proteínas de Microfilamentos/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas de Transporte Vesicular/metabolismo
6.
Stroke ; 55(4): 1032-1040, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38465597

RESUMEN

BACKGROUND: Recent studies, using diffusion tensor image analysis along the perivascular space (DTI-ALPS), suggest impaired perivascular space (PVS) function in cerebral small vessel disease, but they were cross-sectional, making inferences on causality difficult. We determined associations between impaired PVS, measured using DTI-ALPS and PVS volume, and cognition and incident dementia. METHODS: In patients with lacunar stroke and confluent white matter hyperintensities, without dementia at baseline, recruited prospectively in a single center, magnetic resonance imaging was performed annually for 3 years, and cognitive assessments, including global, memory, executive function, and processing speed, were performed annually for 5 years. We determined associations between DTI-ALPS and PVS volume with cerebral small vessel disease imaging markers (white matter hyperintensity volume, lacunes, and microbleeds) at baseline and with changes in imaging markers. We determined whether DTI-ALPS and PVS volume at baseline and change over 3 years predicted incident dementia. Analyses were controlled for conventional diffusion tensor image metrics using 2 markers (median mean diffusivity [MD] and peak width of skeletonized MD) and adjusted for age, sex, and vascular risk factors. RESULTS: A total of 120 patients, mean age 70.0 years and 65.0% male, were included. DTI-ALPS declined over 3 years, while no change in PVS volume was found. Neither DTI-ALPS nor PVS volume was associated with cerebral small vessel disease imaging marker progression. Baseline DTI-ALPS was associated with changes in global cognition (ß=0.142, P=0.032), executive function (ß=0.287, P=0.027), and long-term memory (ß=0.228, P=0.027). Higher DTI-ALPS at baseline predicted a lower risk of dementia (hazard ratio, 0.328 [0.183-0.588]; P<0.001), and this remained significant after including median MD as a covariate (hazard ratio, 0.290 [0.139-0.602]; P<0.001). Change in DTI-ALPS predicted dementia conversion (hazard ratio, 0.630 [0.428-0.964]; P=0.048), but when peak width of skeletonized MD and median MD were entered as covariates, the association was not significant. There was no association between baseline PVS volume, or PVS change over 3 years, and conversion to dementia. CONCLUSIONS: DTI-ALPS predicts future dementia risk in patients with lacunar strokes and confluent white matter hyperintensities. However, the weakening of the association between change in DTI-ALPS and incident dementia after controlling for peak width of skeletonized MD and median MD suggests part of the signal may represent conventional diffusion tensor image metrics. PVS volume is not a predictor of future dementia risk.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales , Trastornos del Conocimiento , Demencia , Accidente Vascular Cerebral Lacunar , Sustancia Blanca , Humanos , Masculino , Anciano , Femenino , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/epidemiología , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Cognición , Trastornos del Conocimiento/etiología , Imagen por Resonancia Magnética/efectos adversos , Accidente Vascular Cerebral Lacunar/diagnóstico por imagen , Accidente Vascular Cerebral Lacunar/epidemiología , Accidente Vascular Cerebral Lacunar/complicaciones , Demencia/diagnóstico por imagen , Demencia/epidemiología , Demencia/complicaciones , Sustancia Blanca/patología
7.
Neuroimage ; 288: 120524, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38278428

RESUMEN

BACKGROUND: Arterial pulsation has been suggested as a key driver of paravascular cerebrospinal fluid flow, which is the foundation of glymphatic clearance. However, whether intracranial arterial pulsatility is associated with glymphatic markers in humans has not yet been studied. METHODS: Seventy-three community participants were enrolled in the study. 4D phase-contrast magnetic resonance imaging (MRI) was used to quantify the hemodynamic parameters including flow pulsatility index (PIflow) and area pulsatility index (PIarea) from 13 major intracerebral arterial segments. Three presumed neuroimaging markers of the glymphatic system were measured: including dilation of perivascular space (PVS), diffusivity along the perivascular space (ALPS), and volume fraction of free water (FW) in white matter. We explored the relationships between PIarea, PIflow, and the presumed glymphatic markers, controlling for related covariates. RESULTS: PIflow in the internal carotid artery (ICA) C2 segment (OR, 1.05; 95 % CI, 1.01-1.10, per 0.01 increase in PI) and C4 segment (OR, 1.05; 95 % CI, 1.01-1.09) was positively associated with the dilation of basal ganglia PVS, and PIflow in the ICA C4 segment (OR, 1.06, 95 % CI, 1.02-1.10) was correlated with the dilation of PVS in the white matter. ALPS was associated with PIflow in the basilar artery (ß, -0.273, p, 0.046) and PIarea in the ICA C2 (ß, -0.239, p, 0.041) and C7 segments (ß, -0.238, p, 0.037). CONCLUSIONS: Intracranial arterial pulsatility was associated with presumed neuroimaging markers of the glymphatic system, but the results were not consistent across different markers. Further studies are warranted to confirm these findings.


Asunto(s)
Sistema Glinfático , Sustancia Blanca , Humanos , Sistema Glinfático/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neuroimagen , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Hemodinámica
8.
Cancer ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38809573

RESUMEN

INTRODUCTION: The histological transformation (HT) of follicular lymphoma (FL) is a crucial biological event. The study aimed to evaluate the incidence, clinicial characteristics, prognosis and impact of HT time on survival of FL transforming to diffuse large B-cell lymphoma in population-based large-scale cohorts. METHODS: A retrospective cohort study of FL with HT was performed in the Surveillance, Epidemiology, and End Results database. The Hematological Malignancy Research Network FL cohort and Aristotle study FL cohort were used to assess the external validity. RESULTS: Among 44,127 FL cases from the Surveillance, Epidemiology, and End Results database, 1311 cases were pathology-proven recorded to transform to diffuse large B-cell lymphoma. The cumulative rates of HT at 5, 10, and 15 years after FL diagnosis were estimated to be 1.19%, 2.93%, and 5.01%, respectively. Significantly worse overall survival and cancer-specific survival were exhibited in patients with HT than those without HT. Early HT (transformation of FL within 48 months after FL diagnosis [TOD48]) was an independent predictor for adverse overall survival of HT patients, regardless of treatment modalities before transformation. The adverse prognostic effect of TOD48 was validated in the Hematological Malignancy Research Network cohort and Aristotle study cohort. Older age (>75 years) and B symptoms within FL at diagnosis were the independent risk factors of TOD48. Furthermore, a novel prognostic model combining TOD48 with Follicular Lymphoma International Prognostic Index (TOD48-FLIPI) was constructed and validated for risk stratification. CONCLUSION: TOD48 was a risk indicator of HT, and the novel prognostic model "TOD48-FLIPI" for HT patients was proposed.

9.
Hum Brain Mapp ; 45(5): e26634, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38553856

RESUMEN

Cerebral small vessel disease (SVD) can disrupt the global brain network and lead to cognitive impairment. Conversely, cognitive reserve (CR) can improve one's cognitive ability to handle damaging effects like SVD, partly by optimizing the brain network's organization. Understanding how SVD and CR collectively influence brain networks could be instrumental in preventing cognitive impairment. Recently, brain redundancy has emerged as a critical network protective metric, providing a nuanced perspective of changes in network organization. However, it remains unclear how SVD and CR affect global redundancy and subsequently cognitive function. Here, we included 121 community-dwelling participants who underwent neuropsychological assessments and a multimodal MRI examination. We visually examined common SVD imaging markers and assessed lifespan CR using the Cognitive Reserve Index Questionnaire. We quantified the global redundancy index (RI) based on the dynamic functional connectome. We then conducted multiple linear regressions to explore the specific cognitive domains related to RI and the associations of RI with SVD and CR. We also conducted mediation analyses to explore whether RI mediated the relationships between SVD, CR, and cognition. We found negative correlations of RI with the presence of microbleeds (MBs) and the SVD total score, and a positive correlation of RI with leisure activity-related CR (CRI-leisure). RI was positively correlated with memory and fully mediated the relationships between the MBs, CRI-leisure, and memory. Our study highlights the potential benefits of promoting leisure activities and keeping brain redundancy for memory preservation in older adults, especially those with SVD.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales , Disfunción Cognitiva , Reserva Cognitiva , Humanos , Anciano , Persona de Mediana Edad , Cognición , Encéfalo/diagnóstico por imagen , Disfunción Cognitiva/psicología , Imagen por Resonancia Magnética , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones
10.
J Magn Reson Imaging ; 2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38329184

RESUMEN

BACKGROUND: Vascular degeneration is an important cause of brain damage in aging. Assessing the functional properties of the cerebral vascular system may aid early diagnosis and prevention. PURPOSE: To investigate the relationships between potential vascular functional markers and vascular risks, brain parenchymal damage, and cognition. STUDY TYPE: Retrospective. SUBJECTS: Two hundred two general community subjects (42-80 years, males/females: 127/75). FIELD STRENGTH/SEQUENCE: 3 T, spin echo T1W/T2W/FLAIR, resting-state functional MRI with an echo-planar sequence (rsfMRI), pseudo-continuous arterial spin labeling (pCASL) with a three-dimensional gradient-spin echo sequence. ASSESSMENT: Cerebral blood flow (CBF) in gray matter calculated using pCASL, blood transit times calculated using rsfMRI, and the SD of internal carotid arteries signal (ICAstd ) calculated using rsfMRI; visual assessment for lacunes; quantification of white matter hyperintensity volume; permutation test for quality control; collection of demographic and clinical data, Montreal Cognitive Assessment, Mini-Mental State Examination. STATISTICAL TESTS: Kolmogorov-Smirnov test; Spearman rank correlation analysis; Multivariable linear regression analysis controlling for covariates; The level of statistical significance was set at P < 0.05. RESULTS: Age was negatively associated with ICAstd (ß = -0.180). Diabetes was associated with longer blood transit time from large arteries to capillary bed (ß = 0.185, adjusted for age, sex, and intracranial volume). Larger ICAstd was associated with less presence of lacunes (odds ratio: 0.418, adjusted for age and sex). Higher gray matter CBF (ß = 0.154) and larger ICAstd (ß = 0.136) were associated with better MoCA scores (adjusted for age, sex, and education). DATA CONCLUSION: Prolonged blood transit time, decreased ICAstd , and diminished CBF were associated with vascular dysfunction and cognitive impairment. They may serve as vascular functional markers in future studies. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.

11.
PLoS Genet ; 17(6): e1009618, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34115759

RESUMEN

Coordination of neurite extension with surrounding glia development is critical for neuronal function, but the underlying molecular mechanisms remain poorly understood. Through a genome-wide mutagenesis screen in C. elegans, we identified dyf-4 and daf-6 as two mutants sharing similar defects in dendrite extension. DAF-6 encodes a glia-specific patched-related membrane protein that plays vital roles in glial morphogenesis. We cloned dyf-4 and found that DYF-4 encodes a glia-secreted protein. Further investigations revealed that DYF-4 interacts with DAF-6 and functions in a same pathway as DAF-6 to regulate sensory compartment formation. Furthermore, we demonstrated that reported glial suppressors of daf-6 could also restore dendrite elongation and ciliogenesis in both dyf-4 and daf-6 mutants. Collectively, our data reveal that DYF-4 is a regulator for DAF-6 which promotes the proper formation of the glial channel and indirectly affects neurite extension and ciliogenesis.


Asunto(s)
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Genoma de los Helmintos , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas del Tejido Nervioso/genética , Neurogénesis/genética , Animales , Caenorhabditis elegans/citología , Caenorhabditis elegans/crecimiento & desarrollo , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Comunicación Celular , Cilios/genética , Cilios/metabolismo , Clonación Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Vectores Genéticos/química , Vectores Genéticos/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Mutagénesis , Proteínas del Tejido Nervioso/metabolismo , Neuritas/metabolismo , Neuroglía/citología , Neuroglía/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
12.
J Integr Neurosci ; 23(1): 12, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38287842

RESUMEN

BACKGROUND: The acute changes that occur in the small-world topology of the brain in concussion patients remain unclear. Here, we investigated acute changes in the small-world organization of brain networks in concussion patients and their influence on persistent post-concussion symptoms. METHODS: Eighteen concussion patients and eighteen age-matched controls were enrolled in this study. All participants underwent computed tomography, magnetic resonance imaging (MRI), susceptibility weighted imaging, and blood oxygen level-dependent functional MRI. A complex network analysis method based on graph theory was used to calculate the parameters of small-world networks under different degrees of network sparsity. All subjects were evaluated using the Glasgow Coma Scale and Rivermead Postconcussion Symptom Questionnaire. RESULTS: Compared with the controls, the normalized cluster coefficient (γ) of whole brain networks in patients and the "small-world" index (σ) was slightly enhanced, whereas the standardized minimum path (λ) was slightly shorter. Whole brain effect (Eglobal) and local effect (Elocal) changes were not pronounced. Under the condition of minimum network sparsity (Dmin = 0.13), the numbers of nodes in the "right intraorbital superior frontal gyrus" (Anatomical Automatic Labeling, AAL26), right globus pallidus (AAL76), and bilateral temporal transverse gyrus (AAL79,80) in brain concussion patients were significantly lower. The numbers of nodes in the left subcapital lobe (AAL61) and left occipital gyrus (AAL51) were significantly higher, and the normalized cluster coefficients of the right intraorbital supraphalus (AAL26) and left posterior cingulate gyrus (AAL35) were significantly increased. The normalized clustering coefficients of the right triangular subfrontal gyrus (AAL55) (based on the normalized clustering coefficients of nodes in AAL14) and left sub-parietal lobes (AAL61) were significantly reduced. The mean local effects of nodes in the right intraorbital upper frontal gyrus (AAL26), left posterior cingulate gyrus (AAL35), and bilateral auxiliary motor cortex (AAL19, 20) were enhanced, whereas the mean local effects of the bilateral triangular inferior frontal gyrus (AAL13,14) and left insular cap (AAL11) were reduced (p < 0.05). CONCLUSIONS: The overall trend of network topology abnormalities in patients was random, and generalized and local functional abnormalities were seen. Changes in the function and affective circuitry of the resting default network were particularly pronounced in these patients, which we speculate may be one of the main drivers of the cognitive dysfunction and mood changes seen in concussion patients.


Asunto(s)
Conmoción Encefálica , Humanos , Conmoción Encefálica/diagnóstico por imagen , Conmoción Encefálica/patología , Encéfalo , Mapeo Encefálico/métodos , Lóbulo Parietal , Lóbulo Frontal , Imagen por Resonancia Magnética/métodos
13.
Nano Lett ; 23(18): 8498-8504, 2023 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-37695649

RESUMEN

Reining in deformation twinning is crucial for the mechanical properties of hexagonal close-packed (HCP) metals and hinges on an explicit understanding of the twinning nucleation mechanism. Unfortunately, it is often suggested rather than conclusively demonstrated that twinning nucleation can be mediated by pure atomic shuffles. Herein, by utilizing in situ high-resolution transmission electron microscopy, we have dissected the atomic shuffling mechanism during the {101̅2} twinning nucleation in rhenium nanocrystals, which revealed the emergence of an intermediate body-centered tetragonal (BCT) structure. Specifically, the double-layered prismatic planes initially shuffle into single-layered {11̅0}BCT planes; subsequently, adjacent {22̅0}BCT planes shuffle in opposite directions to form the basal planes of the twin embryo. This shuffling mechanism is further corroborated by molecular dynamic simulations. The finding provides direct evidence of shuffle-dominated twinning nucleation with atomic details that may lead to better control of this critical twinning mode in HCP metals.

14.
Nano Lett ; 23(5): 1801-1809, 2023 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-36826373

RESUMEN

The reprogramming of cell signaling and behavior through the artificial control of cell surface receptor oligomerization shows great promise in biomedical research and cell-based therapy. However, it remains challenging to achieve combinatorial recognition in a complicated environment and logical regulation of receptors for desirable cellular behavior. Herein, we develop a logic-gated DNA nanodevice with responsiveness to multiple environmental inputs for logically controlled assembly of heterogeneous receptors to modulate signaling. The "AND" gate nanodevice uses an i-motif and an ATP-binding aptamer as environmental cue-responsive units, which can successfully implement a logic operation to manipulate receptors on the cell surface. In the presence of both protons and ATP, the DNA nanodevice is activated to selectively assemble MET and CD71, which modulate the HGF/MET signaling, resulting in cytoskeletal reorganization to inhibit cancer cell motility in a tumor-like microenvironment. Our strategy would be highly promising for precision therapeutics, including controlled drug release and cancer treatment.


Asunto(s)
ADN , Neoplasias , Humanos , ADN/genética , Oligonucleótidos , Transducción de Señal , Neoplasias/tratamiento farmacológico , Adenosina Trifosfato , Microambiente Tumoral
15.
J Sci Food Agric ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38860545

RESUMEN

BACKGROUND: Morden advanced analytical tools offer valuable information into the understanding of molecular mechanism of traditional food processing. Chopping temperature is well-known to affect the surimi gel quality of silver carp, but the detailed molecular mechanism is not very clear. In this study, a gel-based proteomics was performed on the extracted surimi proteins under different chopping temperatures (0, 5, 10, and 25 °C) along with other physicochemical characterization of surimi proteins and gels. RESULTS: With increased chopping temperature, protein extractability (in 3% sodium chloride) generally decreased, while the extracted protein generally exhibited larger surface hydrophobicity, reduced intrinsic fluorescence intensity, lower sulfhydryl content. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) profile of extracted protein showed a clear difference at 25 °C when compared with the other three temperatures, and more protein fragmentation occurred. Proteomic analysis of selected bands indicated that major myofibrillar proteins react differently with chopping temperatures, especially at 25 °C. The selected bands contained a variety of other proteins or their fragments, including adenosine triphosphate (ATP) synthase, glyceraldehyde-3-phosphate dehydrogenase, glucose-6-phosphate isomerase, heat shock protein, parvalbumin, collagen, and so forth. For the surimi gel, water-holding capacity and gel strength generally decreased with increased chopping temperature. CONCLUSION: Our results suggested that chopping at 0-10 °C is acceptable for the production of silver carp surimi in terms of gel strength and water-holding capacity. However, a chopping temperature near 0 °C led to less protein oxidation and denaturation. The inferior gel quality at 25 °C is linked to a decreased concentration of extracted protein and degradation of major myofibrillar protein, the latter is likely crosslinked with sarcoplasmic proteins. © 2024 Society of Chemical Industry.

16.
Water Sci Technol ; 89(3): 562-575, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38358489

RESUMEN

The three-dimensional electrocatalytic oxidation (3DEO) is a promising electrochemical system in the treatment of refractory wastewater, but still far from large-scale applications. In this work, we prepared 146.5 Kg Ti-Sn-Sb@γ-Al2O3 particle electrodes to construct a 3DEO system for the pretreatment of hypersaline and high-organic wastewater in an industrial park sewage plant, with activated carbon particle electrodes as a comparison. The average COD removal rates of Ti-Sn-Sb@γ-Al2O3 and activated carbon-based 3DEO systems were 24.43 and 48.73%, respectively, and the energy consumption of the two 3DEO systems were 102.8 and 31.4 kWh/Kg COD, respectively. However, compared to the negligible enhancement of wastewater biodegradability in the activated carbon 3DEO system, the Ti-Sn-Sb@γ-Al2O3 3DEO system greatly improved the biochemical index (B/C) from 0.021 to 0.166 (by 690.5%). Due to its superior catalytic capacity, Ti-Sn-Sb@γ-Al2O3 outperforms activated carbon in improving biodegradability as the latter relies mainly on adsorption. The results of this work provide a 3DEO engineering practice experience on the pretreatment of hypersaline and high-organic wastewater.


Asunto(s)
Carbón Orgánico , Aguas Residuales , Aguas del Alcantarillado , Adsorción , Catálisis
17.
Dermatol Online J ; 30(1)2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38762856

RESUMEN

Generalized pustular psoriasis is a rare variant of psoriasis. Evidence recommending generalized pustular psoriasis treatment with secukinumab is limited. This report aims to evaluate the use of secukinumab in two patients with generalized pustular psoriasis. The standard treatment regimen for secukinumab was as follows: 300mg subcutaneously once weekly in weeks 0-4, followed by 300mg every four weeks. The efficacy was evaluated by analyzing the psoriasis area and severity index (PASI) and dermatology life quality index (DLQI). One patient had generalized pustular psoriasis, which had developed from palmoplantar pustulosis over 12 years. The second patient was an adolescent with recurrent generalized pustular psoriasis. The first patient achieved PASI-75 response by week 3 and both PASI-90 and a DLQI score of 0 were observed by week 8. The second patient achieved PASI-75 response by week 4 and complete clinical resolution, except for nail changes, and a DLQI of 0 by week 8, without any adverse events.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Psoriasis , Índice de Severidad de la Enfermedad , Humanos , Psoriasis/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Masculino , Adolescente , Femenino , Anticuerpos Monoclonales/uso terapéutico , Fármacos Dermatológicos/uso terapéutico , Calidad de Vida , Adulto
18.
Neuroimage ; 279: 120305, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37562719

RESUMEN

BACKGROUND: Large heterogeneity can be found in dopamine responsiveness of patients with Parkinson's disease (PD). Instantly and objectively understanding dopamine responsiveness of patients may help clinical practice. PURPOSE: This PD study explored the predictability of off-state inter-regional cerebral blood flow (CBF) perfusion similarity on patient's dopamine responsiveness and tested whether the predictive power could be moderated by patient's cognitive status. MATERIALS AND METHOD: The PD cohort with 192 patients (containing off state and on state (PD-off and PD-on)) and the normal control (NC) cohort with 92 subjects were included. The intra-individual CBF relative variation networks were constructed and compared between PD-off and PD-on, PD-off and NC to identify the alterations caused by dopamine depletion. Based on that, regression analysis of off-state inter-regional CBF perfusion similarity on patient's dopamine responsiveness was performed. Finally, moderation analysis was conducted to test the moderation role of cognition on the regression model. RESULTS: In the PD-off cohort, a total of 82 edges in the network were identified that affected by dopamine depletion. Off-state inter-regional CBF perfusion similarity was found that had a significant influence on patient's dopamine responsiveness. Cognitive status was validated that positively moderated the relationship between off-state inter-regional CBF perfusion similarity and dopamine responsiveness. CONCLUSION: Dopamine responsiveness of PD patient could be predicted by off-state inter-regional CBF perfusion similarity. Patient's cognitive status might have a positive moderation effect on his/her dopamine responsiveness.


Asunto(s)
Encéfalo , Enfermedad de Parkinson , Humanos , Masculino , Femenino , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/tratamiento farmacológico , Dopamina , Imagen por Resonancia Magnética , Cognición/fisiología , Circulación Cerebrovascular/fisiología , Perfusión
19.
Neurobiol Dis ; 189: 106354, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37977431

RESUMEN

BACKGROUND: Cases with the limbic-predominant age-related TAR DNA-binding protein 43 (TDP-43) encephalopathy neuropathologic change (LATE-NC), Alzheimer's disease (AD), and mixed AD+TDP-43 pathology (AD+LATE-NC) share similar symptoms, which makes it a challenge for accurate diagnosis. Exploring the patterns of gray matter structural covariance networks (SCNs) in these three types may help to clarify the underlying mechanism and provide a basis for clinical interventions. METHODS: We included ante-mortem MRI data of 10 LATE-NC, 39  AD, and 25  AD+LATE-NC from the ADNI autopsy sample. We used four regions of interest (left posterior cingulate cortex, right entorhinal cortex, frontoinsular and dorsolateral prefrontal cortex) to anchor the default mode network (DMN), salience network (SN), and executive control network (ECN). Finally, we assessed the SCN alternations using a multi-regression model-based linear-interaction analysis. RESULTS: Cases with autopsy-confirmed LATE-NC and AD showed increased structural associations involving DMN, ECN, and SN. Cases with AD+LATE-NC showed increased structural association within DMN while decreased structural association between DMN and ECN. The volume of peak clusters showed significant associations with cognition and AD pathology. CONCLUSIONS: This study showed different SCN patterns in the cases with LATE-NC, AD, and AD+LATE-NC, and indicated the network disconnection mechanism underlying these three neuropathological progressions. Further, SCN may serve as an effective biomarker to distinguish between different types of dementia.


Asunto(s)
Enfermedad de Alzheimer , Sustancia Gris , Humanos , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Imagen por Resonancia Magnética , Autopsia , Proteínas de Unión al ADN
20.
Small ; 19(11): e2203647, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36446641

RESUMEN

The previously published report by Wang et al. provides universal equations for evaluating the net CO2 emission via photothermal/thermal CO2 hydrogenation reactions in batch and flow reactors, respectively. However, it remains to be discussed whether the original feed amount or feed rate of H2 should be changed accordingly when the CO2 reduction rate is selected as the variable to investigate the net CO2 emission rate of the system. If not, the reaction would not be in accordance with the stoichiometric ratio, which is inconsistent with reality, bringing about the optimistic scenario in the assessment of CO2 footprint. This work has taken the potential relationship between the original feed amount or feed rate of H2 and CO2 conversion rate into account. The effects of CO2 conversion rate on the net CO2 emission rate in the photothermal catalytic system are re-examined, the obtained trends exhibit more challenging preconditions to achieve net-zero carbon emission than those in the work by Wang et al. The quantitative results indicate that green hydrogen source is indeed vital for carbon neutrality in photothermal CO2 catalysis. Here, the viewpoints will be worth considering and be seen as complementary to the proposed carbon emission assessment equations.

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