Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 851
Filtrar
Más filtros

Intervalo de año de publicación
1.
Development ; 151(2)2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38108472

RESUMEN

Nerves play important roles in organ development and tissue homeostasis. Stem/progenitor cells differentiate into different cell lineages responsible for building the craniofacial organs. The mechanism by which nerves regulate stem/progenitor cell behavior in organ morphogenesis has not yet been comprehensively explored. Here, we use tooth root development in mouse as a model to investigate how sensory nerves regulate organogenesis. We show that sensory nerve fibers are enriched in the dental papilla at the initiation of tooth root development. Through single cell RNA-sequencing analysis of the trigeminal ganglion and developing molar, we reveal several signaling pathways that connect the sensory nerve with the developing molar, of which FGF signaling appears to be one of the important regulators. Fgfr2 is expressed in the progenitor cells during tooth root development. Loss of FGF signaling leads to shortened roots with compromised proliferation and differentiation of progenitor cells. Furthermore, Hh signaling is impaired in Gli1-CreER;Fgfr2fl/fl mice. Modulation of Hh signaling rescues the tooth root defects in these mice. Collectively, our findings elucidate the nerve-progenitor crosstalk and reveal the molecular mechanism of the FGF-SHH signaling cascade during tooth root morphogenesis.


Asunto(s)
Diente , Animales , Ratones , Diente Molar , Morfogénesis/genética , Odontogénesis/genética , Raíz del Diente
2.
Chem Rev ; 123(3): 989-1039, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36580359

RESUMEN

Porous flow fields distribute fuel and oxygen for the electrochemical reactions of proton exchange membrane (PEM) fuel cells through their pore network instead of conventional flow channels. This type of flow fields has showed great promises in enhancing reactant supply, heat removal, and electrical conduction, reducing the concentration performance loss and improving operational stability for fuel cells. This review presents the research and development progress of porous flow fields with insights for next-generation PEM fuel cells of high power density (e.g., ∼9.0 kW L-1). Materials, fabrication methods, fundamentals, and fuel cell performance associated with porous flow fields are discussed in depth. Major challenges are described and explained, along with several future directions, including separated gas/liquid flow configurations, integrated porous structure, full morphology modeling, data-driven methods, and artificial intelligence-assisted design/optimization.

3.
J Biol Chem ; 299(7): 104881, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37269948

RESUMEN

Prion protein (PrP) misfolding is the key trigger in the devastating prion diseases. Yet the sequence and structural determinants of PrP conformation and toxicity are not known in detail. Here, we describe the impact of replacing Y225 in human PrP with A225 from rabbit PrP, an animal highly resistant to prion diseases. We first examined human PrP-Y225A by molecular dynamics simulations. We next introduced human PrP in Drosophila and compared the toxicity of human PrP-WT and Y225A in the eye and in brain neurons. Y225A stabilizes the ß2-α2 loop into a 310-helix from six different conformations identified in WT and lowers hydrophobic exposure. Transgenic flies expressing PrP-Y225A exhibit less toxicity in the eye and in brain neurons and less accumulation of insoluble PrP. Overall, we determined that Y225A lowers toxicity in Drosophila assays by promoting a structured loop conformation that increases the stability of the globular domain. These findings are significant because they shed light on the key role of distal α-helix 3 on the dynamics of the loop and the entire globular domain.


Asunto(s)
Enfermedades por Prión , Proteínas Priónicas , Animales , Humanos , Conejos , Animales Modificados Genéticamente , Drosophila , Enfermedades por Prión/genética , Proteínas Priónicas/química , Proteínas Priónicas/genética , Estabilidad Proteica , Conformación Proteica en Hélice alfa
4.
Neurobiol Dis ; 195: 106497, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38583641

RESUMEN

OBJECTIVES: To elucidate and compare the genetic, clinical, ancillary diagnostic, and pathological characteristics across different Gerstmann-Sträussler-Scheinker disease (GSS) phenotypes and explore the underlying causes of the phenotypic heterogeneities. METHODS: The genetic, clinical, ancillary diagnostic, and pathological profiles of GSS patients reported in the literature were obtained and analyzed. Additionally, 3 patients with genetically confirmed GSS from our unit were included. Based on clinical presentation, patients were classified into typical GSS, Creutzfeldt-Jakob disease (CJD)-like GSS, GSS with dementia, and other categories. RESULTS: A total of 329 GSS cases were included with a 1.13:1 female-to-male ratio, median onset age 44, and median duration 4 years. Of the 294 categorized patients, 50.7% had typical GSS, 24.8% showed CJD-like GSS, and 16.3% presented with GSS with dementia. Clinical classification varied significantly based on genotype, with P102L more common in typical GSS and A117V prevalent in CJD-like GSS. Polymorphism at codon 129 has no effect on GSS phenotype, but the 129 M allele acts as a protective factor in GSS patients in Asia and North America. Moderate to severe spongiform degeneration and the presence of PK-resistant small fragments migrating at <11 kDa on electrophoretic gels along with PrP27-30 fragments were more prevalent in CJD-like GSS phenotype, while hyperphosphorylated tau protein co-deposition tends to be characteristic of typical GSS and GSS with dementia. CONCLUSION: This study reveals GSS's intricate nature, showing significant variations in clinical presentations, diagnostic findings, and pathological features. Mutation sites and pathological changes play crucial roles in determining the GSS clinical heterogeneity.


Asunto(s)
Enfermedad de Gerstmann-Straussler-Scheinker , Fenotipo , Humanos , Enfermedad de Gerstmann-Straussler-Scheinker/genética , Enfermedad de Gerstmann-Straussler-Scheinker/patología , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano
5.
Development ; 148(2)2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33323370

RESUMEN

The control of size and shape is an important part of regulatory process during organogenesis. Tooth formation is a highly complex process that fine-tunes the size and shape of the tooth, which are crucial for its physiological functions. Each tooth consists of a crown and one or more roots. Despite comprehensive knowledge of the mechanism that regulates early tooth crown development, we have limited understanding of the mechanism regulating root patterning and size during development. Here, we show that Ror2-mediated non-canonical Wnt signaling in the dental mesenchyme plays a crucial role in cell proliferation, and thereby regulates root development size in mouse molars. Furthermore, Cdc42 acts as a potential downstream mediator of Ror2 signaling in root formation. Importantly, activation of Cdc42 can restore cell proliferation and partially rescue the root development size defects in Ror2 mutant mice. Collectively, our findings provide novel insights into the function of Ror2-mediated non-canonical Wnt signaling in regulating tooth morphogenesis, and suggest potential avenues for dental tissue engineering.


Asunto(s)
Receptores Huérfanos Similares al Receptor Tirosina Quinasa/metabolismo , Raíz del Diente/embriología , Raíz del Diente/metabolismo , Vía de Señalización Wnt , Proteína de Unión al GTP cdc42/metabolismo , Animales , Diferenciación Celular , Proliferación Celular , Femenino , Masculino , Mesodermo/embriología , Ratones , Ratones Mutantes , Morfogénesis , Odontoblastos/citología , Odontoblastos/metabolismo , Raíz del Diente/citología
6.
Radiology ; 311(1): e230459, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38563669

RESUMEN

Background Microwave ablation (MWA) is currently under preliminary investigation for the treatment of multifocal papillary thyroid carcinoma (PTC) and has shown promising treatment efficacy. Compared with surgical resection (SR), MWA is minimally invasive and could preserve thyroid function. However, a comparative analysis between MWA and SR is warranted to draw definitive conclusions. Purpose To compare MWA and SR for preoperative US-detected T1N0M0 multifocal PTC in terms of overall and 1-, 3-, and 5-year progression-free survival rates and complication rates. Materials and Methods In this retrospective study, 775 patients with preoperative US-detected T1N0M0 multifocal PTC treated with MWA or SR across 10 centers between May 2015 and December 2021 were included. Propensity score matching (PSM) was performed for patients in the MWA and SR groups, followed by comparisons between the two groups. The primary outcomes were overall and 1-, 3-, and 5-year progression-free survival (PFS) rates and complication rates. Results After PSM, 229 patients (median age, 44 years [IQR 36.5-50.5 years]; 179 female) in the MWA group and 453 patients (median age, 45 years [IQR 37-53 years]; 367 female) in the SR group were observed for a median of 20 months (range, 12-74 months) and 26 months (range, 12-64 months), respectively. MWA resulted in less blood loss, shorter incision length, and shorter procedure and hospitalization durations (all P < .001). There was no evidence of differences in overall and 1-, 3-, or 5-year PFS rates (all P > .05) between MWA and SR (5-year rate, 77.2% vs 83.1%; P = .36) groups. Permanent hoarseness (2.2%, P = .05) and hypoparathyroidism (4.0%, P = .005) were encountered only in the SR group. Conclusion There was no evidence of a significant difference in PFS rates between MWA and SR for US-detected multifocal T1N0M0 PTC, and MWA resulted in fewer complications. Therefore, MWA is a feasible option for selected patients with multifocal T1N0M0 PTC. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Georgiades in this issue.


Asunto(s)
Microondas , Neoplasias de la Tiroides , Humanos , Femenino , Adulto , Persona de Mediana Edad , Microondas/uso terapéutico , Estudios Retrospectivos , Cáncer Papilar Tiroideo/diagnóstico por imagen , Cáncer Papilar Tiroideo/cirugía , Hospitalización , Neoplasias de la Tiroides/diagnóstico por imagen , Neoplasias de la Tiroides/cirugía
7.
Small ; : e2401393, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38477692

RESUMEN

Multiphase reactive flow in porous media is an important research topic in many natural and industrial processes. In the present work, photolithography is adopted to fabricate multicomponent mineral porous media in a microchannel, microfluidics experiments are conducted to capture the multiphase reactive flow, methyl violet 2B is employed to visualize the real-time concentration field of the acid solution and a sophisticated image processing method is developed to obtain the quantitative results of the distribution of different phases. With the advanced methods, experiments are conducted with different acid concentration and inlet velocity in different porous structures with different phenomena captured. Under a low acid concentration, the reaction will be single phase. In the gaseous cases with higher acid concentration, preferential flow paths with faster flow and reaction are formed by the multiphase hydrodynamic instabilities. In the experiments with different inlet velocities, it is observed that a higher inlet velocity will lead to a faster reaction but less gas bubbles generated. In contrast, more gas bubbles would be generated and block the flow and reaction under a lower inlet velocity. Finally, in heterogeneous structures, fractures or cavities would significantly redirect the flow and promote the formation of preferential flow path nearby.

8.
Opt Express ; 32(7): 11801-11817, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571019

RESUMEN

A full-quantum approach is used to study the quantum nonlinear properties of a compound Michelson-Sagnac interferometer optomechanical system. By deriving the effective Hamiltonian, we find that the reduced system exhibits a Kerr nonlinear term with a complex coefficient, entirely induced by the dissipative and dispersive couplings. Unexpectedly, the nonlinearities resulting from the dissipative coupling possess non-Hermitian Hamiltonian-like properties preserving the quantum nature of the dispersive coupling beyond the traditional system dissipation. This protective mechanism allows the system to exhibit strong quantum nonlinear effects when the detuning (the compound cavity detuning Δc and the auxiliary cavity detuning Δe) and the tunneling coupling strength (J) of two cavities satisfy the relation J2 = ΔcΔe. Moreover, the additive effects of dispersive and dissipative couplings can produce strong anti-bunching effects, which exist in both strong and weak coupling conditions. Our work may provide a new way to study and produce strong quantum nonlinear effects in dissipatively coupled optomechanical systems.

9.
Acta Neuropathol ; 147(1): 17, 2024 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-38231266

RESUMEN

Definitive diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) relies on the examination of brain tissues for the pathological prion protein (PrPSc). Our previous study revealed that PrPSc-seeding activity (PrPSc-SA) is detectable in skin of sCJD patients by an ultrasensitive PrPSc seed amplification assay (PrPSc-SAA) known as real-time quaking-induced conversion (RT-QuIC). A total of 875 skin samples were collected from 2 cohorts (1 and 2) at autopsy from 2-3 body areas of 339 cases with neuropathologically confirmed prion diseases and non-sCJD controls. The skin samples were analyzed for PrPSc-SA by RT-QuIC assay. The results were compared with demographic information, clinical manifestations, cerebrospinal fluid (CSF) PrPSc-SA, other laboratory tests, subtypes of prion diseases defined by the methionine (M) or valine (V) polymorphism at residue 129 of PrP, PrPSc types (#1 or #2), and gene mutations in deceased patients. RT-QuIC assays of the cohort #1 by two independent laboratories gave 87.3% or 91.3% sensitivity and 94.7% or 100% specificity, respectively. The cohort #2 showed sensitivity of 89.4% and specificity of 95.5%. RT-QuIC of CSF available from 212 cases gave 89.7% sensitivity and 94.1% specificity. The sensitivity of skin RT-QuIC was subtype dependent, being highest in sCJDVV1-2 subtype, followed by VV2, MV1-2, MV1, MV2, MM1, MM1-2, MM2, and VV1. The skin area next to the ear gave highest sensitivity, followed by lower back and apex of the head. Although no difference in brain PrPSc-SA was detected between the cases with false negative and true positive skin RT-QuIC results, the disease duration was significantly longer with the false negatives [12.0 ± 13.3 (months, SD) vs. 6.5 ± 6.4, p < 0.001]. Our study validates skin PrPSc-SA as a biomarker for the detection of prion diseases, which is influenced by the PrPSc types, PRNP 129 polymorphisms, dermatome sampled, and disease duration.


Asunto(s)
Síndrome de Creutzfeldt-Jakob , Enfermedades por Prión , Priones , Humanos , Priones/genética , Enfermedades por Prión/diagnóstico , Enfermedades por Prión/genética , Síndrome de Creutzfeldt-Jakob/diagnóstico , Síndrome de Creutzfeldt-Jakob/genética , Biomarcadores
10.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33649213

RESUMEN

Various neuromodulation approaches have been employed to alter neuronal spiking activity and thus regulate brain functions and alleviate neurological disorders. Infrared neural stimulation (INS) could be a potential approach for neuromodulation because it requires no tissue contact and possesses a high spatial resolution. However, the risk of overheating and an unclear mechanism hamper its application. Here we show that midinfrared stimulation (MIRS) with a specific wavelength exerts nonthermal, long-distance, and reversible modulatory effects on ion channel activity, neuronal signaling, and sensorimotor behavior. Patch-clamp recording from mouse neocortical pyramidal cells revealed that MIRS readily provides gain control over spiking activities, inhibiting spiking responses to weak inputs but enhancing those to strong inputs. MIRS also shortens action potential (AP) waveforms by accelerating its repolarization, through an increase in voltage-gated K+ (but not Na+) currents. Molecular dynamics simulations further revealed that MIRS-induced resonance vibration of -C=O bonds at the K+ channel ion selectivity filter contributes to the K+ current increase. Importantly, these effects are readily reversible and independent of temperature increase. At the behavioral level in larval zebrafish, MIRS modulates startle responses by sharply increasing the slope of the sensorimotor input-output curve. Therefore, MIRS represents a promising neuromodulation approach suitable for clinical application.


Asunto(s)
Conducta Animal/efectos de la radiación , Rayos Infrarrojos , Neuronas/metabolismo , Transducción de Señal/efectos de la radiación , Transmisión Sináptica/efectos de la radiación , Pez Cebra/metabolismo , Potenciales de Acción/efectos de la radiación , Animales , Ratones
11.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(1): 179-184, 2024 Feb 18.
Artículo en Zh | MEDLINE | ID: mdl-38318915

RESUMEN

OBJECTIVE: To analyze the clinical and radiographic effectiveness of a calcium silicate-based bioactive ceramic iRoot BP Plus® pulpotomy of immature permanent teeth with complicated crown fracture and to evaluate the factors influencing its long-term success rate. METHODS: The digital medical records of patients under 13 years old who had undergone iRoot BP Plus® pulpotomy in the Department of Oral Emergency or the First Clinical Division, Peking University School and Hospital of Stomatology from March 2017 to September 2022 due to complicated crown fracture of anterior teeth, and had taken at least one post-operation apical radiograph were reviewed. The clinical and radiographic information at the initial examination and follow-up period were obtained, including crown color, mobility, percussion, cold test (partial pulpotomy teeth), dental restoration, fistula, swelling or inflammation of the gingival tissue, the formation of apical foramen, pathologic radiolucency and calcification of pulp chamber or root canal obliteration. Data were tested by Fisher exact test and a multiple comparison. RESULTS: In the study, 64 patients including 37 males (57.8%) and 27 females (42.2%) with a mean age of 9.1 years : ere finally enrolled. The total number of permanent teeth that received pulpotomy was 75, and the average follow-up time was 19.3 months. The success rate was 93.1% with the time interval between dental injury and treatment in 24 h, while the success rate dropped to 88.2% with the time intervals beyond 24 h. The time intervals did not significantly affect the pulp survival rate (P=0.61) after pulpotomy (partial or coronal). The success rate 6 months after pulpotomy was 96. 0%, and one-year success rate was 94. 7%. A total of 23 cases were reviewed for more than 2 years after pulpotomy, and 6 cases failed. The mobility had no significant effect on the success rate (P=0.28). Pulp chamber calcification and pulp canal obli-teration were not observed in all the post-operative radiographs. CONCLUSION: The one year clinical and radiographic success rates obtained in this study indicate that iRoot BP Plus® is an appropriate pulp capping material option for pulpotomy treatment of complicated crown fracture in immature permanent teeth without displacement injuries. This technique has broad promotional value.


Asunto(s)
Pulpotomía , Fracturas de los Dientes , Masculino , Niño , Femenino , Humanos , Adolescente , Pulpotomía/métodos , Silicatos/uso terapéutico , Compuestos de Calcio/uso terapéutico , Dentición Permanente , Coronas , Fracturas de los Dientes/complicaciones , Fracturas de los Dientes/terapia , Cerámica , Resultado del Tratamiento , Óxidos
12.
Biochem Biophys Res Commun ; 656: 86-96, 2023 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-36958259

RESUMEN

The abnormal immune response mediated by malignant melanoma is related to PD1. Paeonol has pharmacological antitumor activity. Previous studies have indicated that paeonol induces tumor cell apoptosis, but its underlying mechanism in tumor immunity remains unknown. In this study, malignant melanoma was established in normal and thymectomized mice to determine the important role of the thymus in the antitumor effects of paeonol. Paeonol-treated thymocytes were cocultured with melanoma cell spheres to further evaluate the regulatory role of thymocytes in tumor immune dysfunction. Studies have shown that PD1 may be targeted by miR-139-5p. Our results revealed that tumor-induced thymic atrophy was significantly accompanied by high PD1 expression and low miR-139-5p expression. Interestingly, paeonol significantly reversed thymic atrophy and largely protected thymocytes against low PD1 expression and high miR-139-5p expression. Dual-luciferase assays indicated that miR-139-5p interacted with the 3' untranslated region (3'-UTR) of PD1. These results showed that paeonol alleviates PD1-mediated antitumor immunity by reducing miR-139-5p expression and demonstrated a novel mechanism for melanoma immunotherapy.


Asunto(s)
Melanoma , MicroARNs , Animales , Ratones , Regulación hacia Arriba , MicroARNs/genética , MicroARNs/metabolismo , Línea Celular Tumoral , Melanoma/tratamiento farmacológico , Melanoma/genética , Melanoma/patología , Apoptosis , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Melanoma Cutáneo Maligno
13.
Opt Lett ; 48(20): 5289-5292, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37831849

RESUMEN

Surface plasmonic detectors based on one-dimensional half-wavelength gratings have attracted attention due to their wavelength- or polarization-specific photodetection. Although the effect of a grating period and a grating depth on the photoelectric conversion of 1D half-wavelength grating-based surface plasmon resonance (SPR) detectors has been discussed thoroughly in recent years, the effect of different grating profiles on device performance is still limited to the rectangular shape. In this article, we proposed a wavelength sensitivity reconfigurable photodetector enhanced by SPR with a blazed grating profile. The gold layer was fabricated on a silicon-based blazed grating to form a Schottky barrier and act as an SPR coupler. By measuring the photocurrent in the range of -58° to -48°of an incident angle, the peak shifts of a photocurrent signal waveform are found to depend on the wavelength over 800-1000 nm.

14.
Cancer Cell Int ; 23(1): 137, 2023 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-37452413

RESUMEN

BACKGROUND: The metastasis of breast cancer (BC) is a complex multi-step pathological process, strictly dependent on the intrinsic characteristics of BC cells and promoted by a predisposing microenvironment. Although immunotherapy has made important progress in metastasis BC, the heterogeneity of PD-L1 in tumor associated macrophages (TAMs) in BC and the underlying mechanisms in the metastasis development of BC are still not completely elucidated. Small extracellular vesicles (sEVs) represent essential interaction mediators between BC cells and TAMs. It is worth noting to explore the underlying mechanisms typical of sEVs and their role in the metastasis development of BC. METHODS: The structure of sEVs was identified by TEM, while the particle size and amounts of sEVs were detected by BCA and NTA analysis. The specific PD-L1 + CD163 + TAM subpopulation in metastasis BC was identified by scRNA-seq data of GEO datasets and verified by IHC and IF. The function of TAMs and sEVs in metastasis BC was explored by RT-qPCR, WB, IF, flow cytometry and in vivo experiment. The expression profiles of plasma sEVs-miRNA in relation to BC metastasis was analyzed using next-generation sequencing. Further detailed mechanisms of sEVs in the metastasis development of BC were explored by bioinformatics analysis, RT-qPCR, WB and luciferase reporter assay. RESULTS: In this study, we identified that the immunosuppressive molecule PD-L1 was more abundant in TAMs than in BC cells, and a specific PD-L1 + CD163 + TAM subpopulation was found to be associated with metastasis BC. Additionally, we found that BC cells-derived sEVs can upregulate the PD-L1 expression and induce the M2 polarization, enhancing the metastasis development both in vitro and in vivo. Also, Clinical data showed that sEV-miR-106b-5p and sEV-miR-18a-5p was in relation to BC metastasis development and poor prognosis of BC patients. Further mechanistic experiments revealed that BC-derived sEV-miR-106b-5p and sEV-miR-18a-5p could synergistically promoted the PD-L1 expression in M2 TAMs by modulating the PTEN/AKT and PIAS3/STAT3 pathways, resulting in the enhancement of the BC cells invasion and metastasis. CONCLUSIONS: Our study demonstrated that BC-derived sEVs can induce metastasis in BC through miR-106b-5p/PTEN/AKT/PD-L1 and miR-18a-5p/PIAS3/STAT3/PD-L1 pathways in TAMs. Therefore, the inhibition of these specific interactions of signaling pathways would represent a promising target for future therapeutic strategies for treatment of BC.

15.
PLoS Comput Biol ; 18(10): e1010594, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36215325

RESUMEN

Advanced volumetric imaging methods and genetically encoded activity indicators have permitted a comprehensive characterization of whole brain activity at single neuron resolution in Caenorhabditis elegans. The constant motion and deformation of the nematode nervous system, however, impose a great challenge for consistent identification of densely packed neurons in a behaving animal. Here, we propose a cascade solution for long-term and rapid recognition of head ganglion neurons in a freely moving C. elegans. First, potential neuronal regions from a stack of fluorescence images are detected by a deep learning algorithm. Second, 2-dimensional neuronal regions are fused into 3-dimensional neuron entities. Third, by exploiting the neuronal density distribution surrounding a neuron and relative positional information between neurons, a multi-class artificial neural network transforms engineered neuronal feature vectors into digital neuronal identities. With a small number of training samples, our bottom-up approach is able to process each volume-1024 × 1024 × 18 in voxels-in less than 1 second and achieves an accuracy of 91% in neuronal detection and above 80% in neuronal tracking over a long video recording. Our work represents a step towards rapid and fully automated algorithms for decoding whole brain activity underlying naturalistic behaviors.


Asunto(s)
Encéfalo , Caenorhabditis elegans , Animales , Caenorhabditis elegans/fisiología , Encéfalo/fisiología , Neuronas/fisiología
16.
Diabetes Obes Metab ; 25(12): 3757-3765, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37694762

RESUMEN

AIM: To elucidate how proinsulin synthesis and insulin was affected by metformin under conditions of nutrient overstimulation. MATERIALS AND METHODS: Isolated human pancreatic islets from seven donors were cultured at 5.5 mmol/L glucose and 0.5 mmol/L palmitate for 12, 24 or 72 h. Metformin (25 µmol/L) was introduced after initial 12 h with palmitate. Proinsulin and insulin were measured. Expression of prohormone convertase 1/3 (PC1/3) and carboxypeptidase E (CPE), was determined by western blot. Adolescents with obesity, treated with metformin and with normal glucose tolerance (n = 5), prediabetes (n = 14), or type 2 diabetes (T2DM; n = 7) were included. Fasting proinsulin, insulin, glucose, 2-h glucose and glycated haemoglobin were measured. Proinsulin/insulin ratio (PI/I) was calculated. RESULTS: In human islets, palmitate treatment for 12 and 24 h increased proinsulin and insulin proportionally. After 72 h, proinsulin but not insulin continued to increase which was coupled with reduced expression of PC1/3 and CPE. Metformin normalized expression of PC1/3 and CPE, and proinsulin and insulin secretion. In adolescents with obesity, before treatment, fasting proinsulin and insulin concentrations were higher in subjects with T2DM than with normal glucose tolerance. PI/I was reduced after metformin treatment in subjects with T2DM as well as in subjects with prediabetes, coupled with reduced 2-h glucose and glycated haemoglobin. CONCLUSIONS: Metformin normalized proinsulin and insulin secretion after prolonged nutrient-overstimulation, coupled with normalization of the converting enzymes, in isolated islets. In adolescents with obesity, metformin treatment was associated with improved PI/I, which was coupled with improved glycaemic control.


Asunto(s)
Diabetes Mellitus Tipo 2 , Islotes Pancreáticos , Metformina , Obesidad Infantil , Estado Prediabético , Adolescente , Humanos , Insulina/metabolismo , Proinsulina , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Metformina/farmacología , Metformina/uso terapéutico , Palmitatos/metabolismo , Estado Prediabético/tratamiento farmacológico , Estado Prediabético/metabolismo , Hemoglobina Glucada , Obesidad Infantil/metabolismo , Islotes Pancreáticos/metabolismo , Insulina Regular Humana , Carboxipeptidasa H , Glucosa/metabolismo
17.
Scand J Gastroenterol ; 58(8): 890-899, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36864569

RESUMEN

OBJECTIVES: The short-term efficacy of fecal microbiota transplantation (FMT) for ulcerative colitis (UC) has increasingly been evaluated. However, few studies have examined the long-term efficacy and its predictors. This study aimed to assess the clinical factors affecting the long-term efficacy of FMT for patients with UC. METHODS: This is a retrospective analysis of a prospective trial (NCT01790061) for patients with UC undergoing washed microbiota transplantation (WMT), which is the improved methodology of FMT. The long-term clinical efficacy of WMT and the factors affecting efficacy were analyzed. RESULTS: A total of 259 patients were included for analysis. Of 70.7% (183/259) of patients achieved a clinical response at 1 month after WMT and 29.7% (77/259) achieved steroid-free clinical remission 6 months after WMT. Total 44 patients maintained a clinical response for ≥24 months, and 33 (17.1%, 33/193) achieved steroid-free clinical remission for ≥24 months with WMT monotherapy. Patients with age at UC onset of ≥60 years, mild disease severity and undergoing ≥2 courses of WMT during the response within 6 months were more likely to achieve steroid-free clinical remission 6 months after WMT. Besides, independent factors associated with the long-term response of WMT for UC were age at onset of ≥60 years and ≥2 courses of WMT during the response. CONCLUSIONS: This study indicated WMT could induce short-term steroid-free clinical remission and maintain long-term response in UC, especially for older patients and patients undergoing sequential courses.


Asunto(s)
Colitis Ulcerosa , Microbiota , Humanos , Colitis Ulcerosa/terapia , Colitis Ulcerosa/etiología , Estudios Retrospectivos , Estudios Prospectivos , Trasplante de Microbiota Fecal/métodos , Resultado del Tratamiento , Heces
18.
Brain ; 145(2): 670-683, 2022 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-34983065

RESUMEN

Understanding new modulators of axon regeneration is central to neural repair. Our previous work demonstrated critical roles of atypical cadherin Celsr2 during neural development, including cilia organization, neuron migration and axon navigation. Here, we address its role in axon regeneration. We show that Celsr2 is highly expressed in both mouse and human spinal motor neurons. Celsr2 knockout promotes axon regeneration and fasciculation in mouse cultured spinal explants. Similarly, cultured Celsr2 mutant motor neurons extend longer neurites and larger growth cones, with increased expression of end-binding protein 3 and higher potassium-induced calcium influx. Mice with Celsr2 conditional knockout in spinal motor neurons do not exhibit any behavioural deficits; however, after branchial plexus injury, axon regeneration and functional forelimb locomotor recovery are significantly improved. Similarly, knockdown of CELSR2 using shRNA interference in cultured human spinal motor explants and motor neurons increases axonal fasciculation and growth. In mouse adult spinal cord after root avulsion, in mouse embryonic spinal cords, and in cultured human motor neurons, Celsr2 downregulation is accompanied by increased levels of GTP-bound Rac1 and Cdc42, and of JNK and c-Jun. In conclusion, Celsr2 negatively regulates motor axon regeneration and is a potential target to improve neural repair.


Asunto(s)
Fasciculación Axonal , Traumatismos de la Médula Espinal , Animales , Axones/metabolismo , Cadherinas , Humanos , Ratones , Neuronas Motoras/metabolismo , Regeneración Nerviosa , Médula Espinal , Traumatismos de la Médula Espinal/metabolismo
19.
BMC Endocr Disord ; 23(1): 56, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36882783

RESUMEN

OBJECTIVE: We aimed to explore the association between thyroid hormones and different stages of diabetic kidney disease (DKD) in Chinese adults. METHODS: This is a retrospective study involving 2,832 participants. DKD was diagnosed and classified according to the Kidney Disease: Improving Global Outcomes (KDIGO) categories. Effect sizes are expressed as odds ratio (OR) with 95% confidence interval (CI). RESULTS: After propensity score matching (PSM) on age, gender, hypertension, hemoglobin A1c(HbA1c), total cholesterol (TC), serum triglyceride (TG) and duration of diabetes, per 0.2 pg/mL increment in serum free triiodothyronine (FT3) was significantly associated with 13%, 22% and 37% reduced risk of moderate-risk (OR, 95% CI, P: 0.87, 0.70-0.87, < 0.001), high-risk (0.78, 0.70-0.87, < 0.001) and very-high-risk (0.63, 0.55-0.72, < 0.001) DKD stages relative to the low-risk DKD stage, respectively. After PSM analyses, serum FT4 and TSH showed no statistical significance in risk estimates for all DKD stages. To facilitate clinical application, a nomogram prediction model was established for the moderate-risk, high-risk and very-high-risk DKD stages, with decent accuracy. CONCLUSION: Our results indicate that high concentrations of serum FT3 were associated with the significantly reduced risk of having moderate-risk to very-high-risk DKD stages.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Adulto , Humanos , Nefropatías Diabéticas/diagnóstico , Nefropatías Diabéticas/epidemiología , Nefropatías Diabéticas/etiología , Pueblos del Este de Asia , Estudios Retrospectivos , Hormonas Tiroideas , Triyodotironina
20.
Anesth Analg ; 137(6): 1257-1269, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37973132

RESUMEN

BACKGROUND: Simple and rapid tools for screening high-risk patients for perioperative neurocognitive disorders (PNDs) are urgently needed to improve patient outcomes. We developed an online tool with machine-learning algorithms using routine variables based on multicenter data. METHODS: The entire dataset was composed of 49,768 surgical patients from 3 representative academic hospitals in China. Surgical patients older than 45 years, those undergoing general anesthesia, and those without a history of PND were enrolled. When the patient's discharge diagnosis was PND, the patient was in the PND group. Patients in the non-PND group were randomly extracted from the big data platform according to the surgical type, age, and source of data in the PND group with a ratio of 3:1. After data preprocessing and feature selection, general linear model (GLM), artificial neural network (ANN), and naive Bayes (NB) were used for model development and evaluation. Model performance was evaluated by the area under the receiver operating characteristic curve (ROCAUC), the area under the precision-recall curve (PRAUC), the Brier score, the index of prediction accuracy (IPA), sensitivity, specificity, etc. The model was also externally validated on the multiparameter intelligent monitoring in intensive care (MIMIC) Ⅳ database. Afterward, we developed an online visualization tool to preoperatively predict patients' risk of developing PND based on the models with the best performance. RESULTS: A total of 1051 patients (242 PND and 809 non-PND) and 2884 patients (6.2% patients with PND) were analyzed on multicenter data (model development, test [internal validation], external validation-1) and MIMIC Ⅳ dataset (external validation-2). The model performance based on GLM was much better than that based on ANN and NB. The best-performing GLM model on validation-1 dataset achieved ROCAUC (0.874; 95% confidence interval [CI], 0.833-0.915), PRAUC (0.685; 95% CI, 0.584-0.786), sensitivity (72.6%; 95% CI, 61.4%-81.5%), specificity (84.4%; 95% CI, 79.3%-88.4%), Brier score (0.131), and IPA (44.7%), and of which the ROCAUC (0.761, 95% CI, 0.712-0.809), the PRAUC (0.475, 95% CI, 0.370-0.581), Brier score (0.053), and IPA (76.8%) on validation-2 dataset. Afterward, we developed an online tool (https://pnd-predictive-model-dynnom.shinyapps.io/ DynNomapp/) with 10 routine variables for preoperatively screening high-risk patients. CONCLUSIONS: We developed a simple and rapid online tool to preoperatively screen patients' risk of PND using GLM based on multicenter data, which may help medical staff's decision-making regarding perioperative management strategies to improve patient outcomes.


Asunto(s)
Toma de Decisiones Clínicas , Nomogramas , Humanos , Adulto , Teorema de Bayes , Algoritmos , Factores de Riesgo , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA