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1.
J Comput Assist Tomogr ; 47(2): 212-219, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36790870

RESUMO

PURPOSE: To assess deep learning denoised (DLD) computed tomography (CT) chest images at various low doses by both quantitative and qualitative perceptual image analysis. METHODS: Simulated noise was inserted into sinogram data from 32 chest CTs acquired at 100 mAs, generating anatomically registered images at 40, 20, 10, and 5 mAs. A DLD model was developed, with 23 scans selected for training, 5 for validation, and 4 for test.Quantitative analysis of perceptual image quality was assessed with Structural SIMilarity Index (SSIM) and Fréchet Inception Distance (FID). Four thoracic radiologists graded overall diagnostic image quality, image artifact, visibility of small structures, and lesion conspicuity. Noise-simulated and denoised image series were evaluated in comparison with one another, and in comparison with standard 100 mAs acquisition at the 4 mAs levels. Statistical tests were conducted at the 2-sided 5% significance level, with multiple comparison correction. RESULTS: At the same mAs levels, SSIM and FID between noise-simulated and reconstructed DLD images indicated that images were closer to a perfect match with increasing mAs (closer to 1 for SSIM, and 0 for FID).In comparing noise-simulated and DLD images to standard-dose 100-mAs images, DLD improved SSIM and FID. Deep learning denoising improved SSIM of 40-, 20-, 10-, and 5-mAs simulations in comparison with standard-dose 100-mAs images, with change in SSIM from 0.91 to 0.94, 0.87 to 0.93, 0.67 to 0.87, and 0.54 to 0.84, respectively. Deep learning denoising improved FID of 40-, 20-, 10-, and 5-mAs simulations in comparison with standard-dose 100-mAs images, with change in FID from 20 to 13, 46 to 21, 104 to 41, and 148 to 69, respectively.Qualitative image analysis showed no significant difference in lesion conspicuity between DLD images at any mAs in comparison with 100-mAs images. Deep learning denoising images at 10 and 5 mAs were rated lower for overall diagnostic image quality ( P < 0.001), and at 5 mAs lower for overall image artifact and visibility of small structures ( P = 0.002), in comparison with 100 mAs. CONCLUSIONS: Deep learning denoising resulted in quantitative improvements in image quality. Qualitative assessment demonstrated DLD images at or less than 10 mAs to be rated inferior to standard-dose images.


Assuntos
Aprendizado Profundo , Humanos , Doses de Radiação , Tomografia Computadorizada por Raios X/métodos , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Algoritmos , Razão Sinal-Ruído
2.
Molecules ; 27(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408572

RESUMO

Opioid receptors are members of the group of G protein-couple receptors, which have been proven to be effective targets for treating severe pain. The interactions between the opioid receptors and corresponding ligands and the receptor's activation by different agonists have been among the most important fields in opioid research. In this study, with compound M1, an active metabolite of tramadol, as the clue compound, several aminomethyl tetrahydronaphthalenes were designed, synthesized and assayed upon opioid receptors. With the resultant compounds FW-AII-OH-1 (Ki = 141.2 nM for the κ opioid receptor), FW-AII-OH-2 (Ki = 4.64 nM for the δ opioid receptor), FW-DI-OH-2 (Ki = 8.65 nM for the δ opioid receptor) and FW-DIII-OH-2 (Ki = 228.45 nM for the δ opioid receptor) as probe molecules, the structural determinants responsible for the subtype selectivity and activation mechanisms were further investigated by molecular modeling and molecular dynamics simulations. It was shown that Y7.43 was a key residue in determining the selectivity of the three opioid receptors, and W6.58 was essential for the selectivity of the δ opioid receptor. A detailed stepwise discovered agonist-induced signal transduction mechanism of three opioid receptors by aminomethyl tetrahydronaphthalene compounds was proposed: the 3-7 lock between TM3 and TM7, the DRG lock between TM3 and TM6 and rearrangement of I3.40, P5.50 and F6.44, which resulted in the cooperative movement in 7 TMs. Then, the structural relaxation left room for the binding of the G protein at the intracellular site, and finally the opioid receptors were activated.


Assuntos
Receptores Opioides delta , Receptores Opioides , Simulação de Dinâmica Molecular , Receptores Opioides/metabolismo , Receptores Opioides delta/metabolismo , Receptores Opioides mu/metabolismo , Transdução de Sinais , Relação Estrutura-Atividade , Tetra-Hidronaftalenos
3.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(2): 265-270, 2022 Feb 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-35545418

RESUMO

More than 100 genes located on the X chromosome have been found to be associated with X-linked intellectual disability (XLID) to date, and NEXMIF is a pathogenic gene for XLID. In addition to intellectual disability, patients with NEXMIF gene mutation can also have other neurological symptoms, such as epilepsy, abnormal behavior, and hypotonia, as well as abnormalities of other systems. Two children with intellectual disability and epilepsy caused by NEXMIF gene mutation were treated in the Department of Pediatrics, Xiangya Hospital, Central South University from March 8, 2017 to June 20, 2020. Patient 1, a 7 years and 8 months old girl, visited our department because of the delayed psychomotor development. Physical examination revealed strabismus (right eye), hyperactivity, and loss of concentration. Intelligence test showed a developmental quotient of 43.6. Electroencephalogram showed abnormal discharge, and cranial imaging appeared normal. Whole exome sequencing revealed a de novo heterozygous mutation, c.2189delC (p.S730Lfs*17) in the NEXMIF gene (NM_001008537). During the follow-up period, the patient developed epileptic seizures, mainly manifested as generalized and absent seizures. She took the medicine of levetiracetam and lamotrigine, and the seizures were under control. Patient 2, a 6-months old boy, visited our department due to developmental regression and seizures. He showed poor reactions to light and sound, and was not able to raise head without aid. Hypotonia was also noticed. The electroencephalogram showed intermittent hyperarrhythmia, and spasms were monitored. He was given topiramate and adrenocorticotrophic hormone (ACTH). Whole exome sequencing detected a de novo c.592C>T (Q198X) mutation in NEXMIF gene. During the follow-up period, the seizures were reduced with vigabatrin. He had no obvious progress in the psychomotor development, and presented strabismus. There were 91 cases reported abroad, 1 case reported in China, and 2 patients were included in this study. A total of 85 variants in NEXMIF gene were found, involving 83 variants reported in PubMed and HGMD, and the 2 new variants presented in our patients. The patients with variants in NEXMIF gene all had mild to severe intellectual disability. Behavioral abnormalities, epilepsy, hypotonia, and other neurological symptoms are frequently presented. The phenotype of male partially overlaps with that of female. Male patients often have more severe intellectual disability, impaired language, and autistic features, while female patients often have refractory epilepsy. Most of the variants reported so far were loss-of-function resulted in the reduced protein expression of NEXMIF. The degree of NEXMIF loss appears to correlate with the severity of the phenotype.


Assuntos
Epilepsia , Deficiência Intelectual , Proteínas do Tecido Nervoso , Criança , Epilepsia/complicações , Epilepsia/genética , Feminino , Humanos , Deficiência Intelectual/complicações , Deficiência Intelectual/genética , Masculino , Hipotonia Muscular/complicações , Mutação , Proteínas do Tecido Nervoso/genética , Fenótipo , Convulsões/genética , Estrabismo/complicações
4.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(4): 432-437, 2021 Apr 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-33967092

RESUMO

Cardio-facio-cutaneous (CFC) syndrome is an extremely rare autosomal dominant genetic disease due to BRAF and other gene mutations. The main characteristics of the patients are craniofacial deformities, cardiac malformations, skin abnormalities, delay of language and motor development, gastrointestinal dysfunction, intellectual disability, and epilepsy. In this case, the child has a typical CFC syndrome face and developmental delay. The gene results of the second-generation sequencing technology showed that there was a mutation site c.1741A>G (p. Asn581Asp) (heterozygous) in exon 14 of the BRAF (NM_004333.5) gene. The mutation was not observed in the child's parents. The above-mentioned mutation may be a de novo mutation. There is no effective therapy for this disease so far.


Assuntos
Anormalidades Múltiplas , Displasia Ectodérmica , Cardiopatias Congênitas , Criança , Displasia Ectodérmica/genética , Fácies , Insuficiência de Crescimento , Cardiopatias Congênitas/genética , Humanos , Mutação , Proteínas Proto-Oncogênicas B-raf/genética
5.
Biochem Biophys Res Commun ; 527(2): 511-517, 2020 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-32423796

RESUMO

Mounting evidence has illustrated the tumor regulatory roles of microRNAs (miRNAs) in T-cell acute lymphoblastic leukemia (T-ALL), a malignant carcinoma originated from T-cell precursors. However, the possible regulation mechanisms underlying miR-29b/29c-3p in T-ALL have not been interrogated yet. The aim of our study was to probe the association and possible molecular mechanism of miR-29b/29c-3p and Glutathione Peroxidase 1 (GPX1), a predicted highly expressed gene in acute myeloid leukemia (LAML) tissues on the cancer genome atlas (TCGA) website. In our paper, it was observed that GPX1 was relatively overexpressed in T-ALL cells, compared with normal T cells. Loss-of-function assays demonstrated that GPX1 knockdown inhibited the proliferation and activated the apoptosis in T-ALL cells. Then miR-29b/29c-3p was confirmed to regulate GPX1 mRNA and protein expression via decreasing Transcription Factor AP-2 Gamma (TFAP2C) expression. In summary, miR-29b-3p and miR-29c-3p targeted TFAP2C so as to repress GPX1 transcription, thereafter inhibiting GPXA expression. In the end, rescue experiments proved the whole regulation mechanism of miR-29b/29c-3p in T-ALL. Overall, the miR-29b/29c-3p -TFAP2C-GPX1 axis helped us to have a better understanding of T-ALL pathogenesis.


Assuntos
Regulação Leucêmica da Expressão Gênica , Glutationa Peroxidase/genética , MicroRNAs/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Fator de Transcrição AP-2/genética , Apoptose , Linhagem Celular Tumoral , Humanos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Glutationa Peroxidase GPX1
6.
Entropy (Basel) ; 21(1)2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33266780

RESUMO

Wave height and wave period are important oceanic environmental factors that are used to describe the randomness of a wave. Within the field of ocean engineering, the calculation of design wave height is of great significance. In this paper, a periodic maximum entropy distribution function with four undetermined parameters is derived by means of coordinate transformation and solving conditional variational problems. A double entropy joint distribution function of wave height and wave period is also derived. The function is derived from the maximum entropy wave height function and the maximum entropy periodic function, with the help of structures of the Copula function. The double entropy joint distribution function of wave height and wave period is not limited by weak nonlinearity, nor by normal stochastic process and narrow spectrum. Besides, it can fit the observed data more carefully and be more widely applicable to nonlinear waves in various cases, owing to the many undetermined parameters it contains. The engineering cases show that the recurrence level derived from the double entropy joint distribution function is higher than that from the extreme value distribution using the single variables of wave height or wave period. It is also higher than that from the traditional joint distribution function of wave height and wave period.

7.
J Cell Biochem ; 119(3): 2787-2796, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29053187

RESUMO

LncRNAs and microRNAs can play significant roles in various cancers, including gastric cancer (GC). In our study, we investigated the role of lncRNA XIST in GC. We observed that XIST was increased in MGC803 and BGC823 cells compared to human normal gastric epithelial GES-1 cells. It was also shown that miR-185 was decreased in GC cell lines. Silencing XIST can inhibit the growth of GC cells and bioinformatics analysis was performed to confirm the correlation between XIST and miR-185. Interestingly, a negative correlation was indicated between XIST and miR-185 in GC cells. In addition, TGF-ß1 was predicted as a target gene of miR-185. miR-185 can modulate TGF-ß1 expression negatively in vitro. Moreover, we found that sh-XIST inhibited GC development via decreasing TGF-ß1 by upregulating miR-185 in vitro. Therefore, we speculated that XIST can act as a competing endogenous lncRNA (ceRNA) to regulate TGF-ß1 by sponging miR-185 in GC. Taken these together, it was indicated that XIST/miR-185/TGF-ß1 axis participated in the development of GC. XIST could act as a potential prognostic biomarker in GC development.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Proteínas de Neoplasias/biossíntese , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo , Neoplasias Gástricas/metabolismo , Fator de Crescimento Transformador beta1/biossíntese , Regulação para Cima , Linhagem Celular Tumoral , Células HEK293 , Humanos , MicroRNAs/genética , Proteínas de Neoplasias/genética , RNA Longo não Codificante/genética , RNA Neoplásico/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Fator de Crescimento Transformador beta1/genética
8.
Neural Netw ; 179: 106557, 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39106566

RESUMO

Unsupervised semantic segmentation is important for understanding that each pixel belongs to known categories without annotation. Recent studies have demonstrated promising outcomes by employing a vision transformer backbone pre-trained on an image-level dataset in a self-supervised manner. However, those methods always depend on complex architectures or meticulously designed inputs. Naturally, we are attempting to explore the investment with a straightforward approach. To prevent over-complication, we introduce a simple Dense Embedding Contrast network (DECNet) for unsupervised semantic segmentation in this paper. Specifically, we propose a Nearest Neighbor Similarity strategy (NNS) to establish well-defined positive and negative pairs for dense contrastive learning. Meanwhile, we optimize a contrastive objective named Ortho-InfoNCE to alleviate the false negative problem inherent in contrastive learning for further enhancing dense representations. Finally, extensive experiments conducted on COCO-Stuff and Cityscapes datasets demonstrate that our approach outperforms state-of-the-art methods.

9.
Comput Biol Med ; 169: 107811, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38168647

RESUMO

Graph Neural Networks (GNNs) have gained significant traction in various sectors of AI-driven drug design. Over recent years, the integration of fragmentation concepts into GNNs has emerged as a potent strategy to augment the efficacy of molecular generative models. Nonetheless, challenges such as symmetry breaking and potential misrepresentation of intricate cycles and undefined functional groups raise questions about the superiority of fragment-based graph representation over traditional methods. In our research, we undertook a rigorous evaluation, contrasting the predictive prowess of eight models-developed using deep learning algorithms-across 12 benchmark datasets that span a range of properties. These models encompass established methods like GCN, AttentiveFP, and D-MPNN, as well as innovative fragment-based representation techniques. Our results indicate that fragment-based methodologies, notably PharmHGT, significantly improve model performance and interpretability, particularly in scenarios characterized by limited data availability. However, in situations with extensive training, fragment-based molecular graph representations may not necessarily eclipse traditional methods. In summation, we posit that the integration of fragmentation, as an avant-garde technique in drug design, harbors considerable promise for the future of AI-enhanced drug design.


Assuntos
Algoritmos , Benchmarking , Desenho de Fármacos , Modelos Moleculares , Redes Neurais de Computação
10.
Int J Biol Macromol ; 263(Pt 2): 130440, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38417763

RESUMO

To address the issue of food spoilage causing health and economic loss, we developed a pH/NH3 dual sensitive hydrogel based on polyvinyl alcohol/chitosan (PVA/CS) containing chitosan-phenol red (CP). The CP was synthesized via Mannich reaction and immobilized it in PVA/CS hydrogel through freezing/thawing method to prepare the final PVA/CS/CP hydrogel. The synthesis of CP was confirmed by 1H NMR, FT-IR, XRD, UV-vis, and XPS. The characteristics of hydrogel were evaluated by FT-IR, XRD, SEM, mechanical properties, thermal stability, leaching, and color stability tests. The PVA/CS/CP hydrogel showed distinctly different color at various pH and NH3 vapor levels (yellow to purple). The hydrogel exhibited obvious color changes (ΔE = 46.95) in response to shrimp spoilage, stored at 4 °C. It showed positive and strong correlation between the ΔE values of the indicator hydrogel and total volatile basic nitrogen (TVB-N) as (R2 = 0.9573) and with pH as (R2 = 0.8686), respectively. These results clearly show that the PVA/CS/CP hydrogel could be applied for naked-eye real-time monitoring of seafood freshness in intelligent packaging.


Assuntos
Quitosana , Quitosana/química , Álcool de Polivinil/química , Espectroscopia de Infravermelho com Transformada de Fourier , Hidrogéis/química , Alimentos Marinhos , Concentração de Íons de Hidrogênio , Embalagem de Alimentos/métodos , Antocianinas/química
11.
Pediatr Neurol ; 153: 137-143, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38382246

RESUMO

BACKGROUND: Currently, there is no universally accepted standard treatment for ocular myasthenia gravis (OMG) in children. We aimed to investigate the possible proper regimens and timing of treatment for pediatric OMG cases based on the clinical manifestations: OMG with ptosis only and OMG with other features. METHODS: One hundred and forty two OMG cases attended at the Department of Pediatrics, Xiangya Hospital, Central South University, from 2010 to 2019 were included, and information from medical records was reviewed and recorded. Comparisons of clinical characteristics between patients with OMG with ptosis only and patients with OMG with other features as well as between patients treated with glucocorticoid (GC) within or after six months from disease onset were performed. RESULTS: OMG with other features constituted about 54.9% of the cases, and 66.2% of the patients achieved optimal outcome. Patients with OMG with ptosis only responded to pyridostigmine alone more than patients with OMG with other features who required several therapies (P < 0.001). Patients with OMG with ptosis only had a larger proportion of optimal outcome than the patients with OMG with other features (P = 0.002), and the difference remained significant even when the individual outcome groups were compared (P < 0.001). Patients who received GC within six months had a greater proportion of optimal outcome than those who received it after six months (P < 0.001). CONCLUSIONS: Although OMG with other features is a more common subtype of OMG, it is also more severe than OMG with ptosis only. An earlier addition of GC leads to optimal outcome.


Assuntos
Blefaroptose , Miastenia Gravis , Humanos , Criança , Miastenia Gravis/diagnóstico , Miastenia Gravis/tratamento farmacológico , Blefaroptose/tratamento farmacológico , Blefaroptose/etiologia , Brometo de Piridostigmina/uso terapêutico , Glucocorticoides/uso terapêutico , Estudos Retrospectivos
12.
AJR Am J Roentgenol ; 200(5): W475-82, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23617515

RESUMO

OBJECTIVE: The objective of this study was to evaluate the feasibility of using iterative reconstructions in hepatic CT to improve the precision of Hounsfield unit quantification, which is the degree to which repeated measurements under unchanged conditions provide consistent results. MATERIALS AND METHODS: An anthropomorphic liver phantom with iodinated lesions designed to simulate the enhancement of hypervascular tumors during the late hepatic arterial phase was imaged, and images were reconstructed with both filtered back projection (FBP) and iterative reconstructions, such as adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR). This protocol was further expanded into various dose levels, tube voltages, and slice thicknesses to investigate the effect of iterative reconstructions under all these conditions. The iodine concentrations of the lesions were quantified, with their precision calculated in terms of repeatability coefficient. RESULTS: ASIR reduced image noise by approximately 35%, and improved the quantitative precision by approximately 5%, compared with FBP. MBIR reduced noise by more than 65% and improved the precision by approximately 25% compared with the routine protocol. MBIR consistently showed better precision across a thinner slice thickness, lower tube voltage, and larger patient, achieving the target precision level at a dose lower (≥ 40%) than that of FBP. CONCLUSION: ASIR blended with 50% of FBP indicated a moderate gain in quantitative precision compared with FBP but could achieve more with a higher percentage. A higher gain was achieved by MBIR. These findings may be used to reduce the dose required for reliable quantification and may further serve as a basis for protocol optimization in terms of iodine quantification.


Assuntos
Iodo/farmacocinética , Fígado/diagnóstico por imagem , Fígado/metabolismo , Intensificação de Imagem Radiográfica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Algoritmos , Simulação por Computador , Meios de Contraste/farmacocinética , Humanos , Modelos Biológicos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
13.
Psychol Res Behav Manag ; 16: 561-573, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36873060

RESUMO

Introduction: The Internet has caused a great impact on everyone's psychology. Under this background, it is necessary to study whether Marxism can affect college students' mental health. Methods: Firstly, the introduction explains China's concern for college students' mental health and the research achievements. Then, in the method part, this paper analyzes the thoughts and connotations of basic Marxist theory, quality education, and mental health education, mainly studying the changes brought by the Internet to the development of Marxism and the mechanism and influence of Marxism on mental health education. The questionnaire survey is used to investigate the mental health of college students and the current situation of Marxist ideological and political education. Results: The results show that most college students are not interested in ideological and political education, and from the investigation results of five major factors of life stressors and five indicators of psychological crisis factors, it is concluded that college students' life stressors are the risk factors that induce psychological crisis tendency. Discussion: The discussion part shows that it is necessary to cultivate the core quality of college students' development through Marxism, and pay attention to actively preventing and intervening the psychological crisis of college students. This paper analyzes and confirms the effectiveness of Marxist theory on the development of mental health, injects fresh blood into the future ideological and political education and the research of college students' mental health education, and provides theoretical and experimental reference and new ideas. The research has practical reference value for promoting the deep integration of data-driven Marxist basic theory and college students' mental health monitoring.

14.
Front Mol Neurosci ; 16: 1222321, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37555011

RESUMO

Background: Genotype-phenotype correlations of the CACNA1A-related neurodevelopmental disorders such as global developmental delay (GDD)/intellectual disability (ID), epileptic encephalopathy (EE), and autism spectrum disorder (ASD) are unknown. We aimed to summarize genotype-phenotype correlations and potential treatment for CACNA1A-related neurodevelopmental disorders. Methods: Six children diagnosed with CACNA1A-related neurodevelopmental disorders at Xiangya Hospital, Central South University from April 2018 to July 2021 were enrolled. The PubMed database was systematically searched for all reported patients with CACNA1A-related neurodevelopmental disorders until February 2023. Thereafter, we divided patients into several groups for comparison. Results: Six patients were recruited from our hospital. Three cases presented with epilepsy, five with GDD/ID, five with ataxia, and two with ASD. The variants included p.G701R, p.R279C, p.D1644N, p.Y62C, p.L1422Sfs*8, and p. R1664Q [two gain-of-function (GOF) and four loss-of-function (LOF) variants]. About 187 individuals with GDD/ID harboring 123 variants were found (case series plus data from literature). Of those 123 variants, p.A713T and p.R1664* were recurrent, 37 were LOF, and 7 were GOF. GOF variants were linked with severe-profound GDD/ID while LOF variants were associated with mild-moderate GDD/ID (p = 0.001). The p.A713T variant correlated with severe-profound GDD/ID (p = 0.003). A total of 130 epileptic patients harboring 83 variants were identified. The epileptic manifestations included status epilepticus (n = 64), provoked seizures (n = 49), focal seizures (n = 37), EE (n = 29), absence seizures (n = 26), and myoclonic seizures (n = 10). About 49 (42.20%) patients had controlled seizures while 67 (57.80%) individuals remained with refractory seizures. Status epilepticus correlated with variants located on S4, S5, and S6 (p = 0.000). Among the 83 epilepsy-related variants, 23 were recurrent, 32 were LOF, and 11 were GOF. Status epilepticus was linked with GOF variants (p = 0.000). LOF variants were associated with absence seizures (p = 0.000). Six patients died at an early age (3 months to ≤5 years). We found 18 children with ASD. Thirteen variants including recurrent ones were identified in those 18 cases. GOF changes were more linked to ASD. Conclusion: The p.A713T variant is linked with severe-profound GDD/ID. More than half of CACNA1A-related epilepsy is refractory. The most common epileptic manifestation is status epilepticus, which correlates with variants located on S4, S5, and S6.

15.
Front Mol Neurosci ; 16: 1209760, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37448958

RESUMO

Objective: To investigate the pathogenesis of three novel de novo CACNA1C variants (p.E411D, p.V622G, and p.A272V) in causing neurodevelopmental disorders and arrhythmia. Methods: Several molecular experiments were carried out on transfected human embryonic kidney 293 (HEK 293) and Chinese hamster ovary (CHO) cells to explore the effects of p.E411D, p.V622G, and p.A272V variants on electrophysiology, mitochondrial and lysosomal functions. Electrophysiological studies, RT-qPCR, western blot, apoptosis assay, mito-tracker fluorescence intensity, lyso-tracker fluorescence intensity, mitochondrial calcium concentration test, and cell viability assay were performed. Besides, reactive oxygen species (ROS) levels, ATP levels, mitochondrial copy numbers, mitochondrial complex I, II, and cytochrome c functions were measured. Results: The p.E411D variant was found in a patient with attention deficit-hyperactive disorder (ADHD), and moderate intellectual disability (ID). This mutant demonstrated reduced calcium current density, mRNA, and protein expression, and it was localized in the nucleus, cytoplasm, lysosome, and mitochondria. It exhibited an accelerated apoptosis rate, impaired autophagy, and mitophagy. It also demonstrated compromised mitochondrial cytochrome c oxidase, complex I, and II enzymes, abnormal mitochondrial copy numbers, low ATP levels, abnormal mitochondria fluorescence intensity, impaired mitochondrial fusion and fission, and elevated mitochondrial calcium ions. The p.V622G variant was identified in a patient who presented with West syndrome and moderate global developmental delay. The p.A272V variant was found in a patient who presented with epilepsy and mild ID. Both mutants (p.V622G and p.A272V) exhibited reduced calcium current densities, decreased mRNA and protein expressions, and they were localized in the nucleus, cytoplasm, lysosome, and mitochondria. They exhibited accelerated apoptosis and proliferation rates, impaired autophagy, and mitophagy. They also exhibited abnormal mitochondrial cytochrome c oxidase, complex I and II enzymes, abnormal mitochondrial copy numbers, low ATP, high ROS levels, abnormal mitochondria fluorescence intensity, impaired mitochondrial fusion and fission, as well as elevated mitochondrial calcium ions. Conclusion: The p.E411D, p.V622G and p.A272V mutations of human CACNA1C reduce the expression level of CACNA1C proteins, and impair mitochondrial and lysosomal functions. These effects induced by CACNA1C variants may contribute to the pathogenesis of CACNA1C-related disorders.

16.
Eur J Med Chem ; 247: 115039, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36566711

RESUMO

RORγt plays an important role in mediating IL-17 production and some tumor cells. It has four functional domains, of which the ligand-binding domain (LBD) is responsible for binding agonists to recruit co-activators or inverse agonists to prevent co-activator recruiting the agonists. Thus, potent ligands targeting the LBD of this protein could provide novel treatments for cancer and autoimmune diseases. In this perspective, we summarized and discussed various modes of action (MOA) of RORγt-ligand binding structures. The ligands can bind with RORγt at either orthosteric site or the allosteric site, and the binding modes at these two sites are different for agonists and inverse agonist. At the orthosteric site, the binding of agonist is to stabilize the H479-Y502-F506 triplet interaction network of RORγt. The binding of inverse agonist features as these four apparent ways: (1) blocking the entrance of the agonist pocket in RORγt; (2) directly breaking the H479-Y502 pair interactions; (3) destabilizing the triplet H479-Y502-F506 interaction network through perturbing the conformation of the side chain in M358 at the bottom of the binding pocket; (4) and destabilizing the triplet H479-Y502-F506 through changing the conformation of the side chain of residue W317 side chain. At the allosteric site of RORγt, the binding of inverse agonist was found recently to inhibit the activation of protein by interacting directly with H12, which results in unfolding of helix 11' and orientation of H12 to directly block cofactor peptide binding. This overview of recent advances in the RORγt structures is expected to provide a guidance of designing more potent drugs to treat RORγt-related diseases.


Assuntos
Agonismo Inverso de Drogas , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/agonistas , Ligantes , Receptores do Ácido Retinoico , Ligação Proteica
17.
BMC Med Genomics ; 16(1): 46, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882827

RESUMO

BACKGROUND: We aimed to analyze the genotype-phenotype correlations of STXBP1 pathogenic variants, prognostic factors and the treatment choices in a case-series of STXBP1-related disorders from China. METHODS: The clinical data and genetic results of the children diagnosed with STXBP1-related disorders at Xiangya hospital from 2011 to 2019 were collected retrospectively, and analyzed. We divided our patients into groups for comparison purposes: patients with missense variants and nonsense variants, patients who are seizure-free and not seizure-free, patients with mild to moderate intellectual disability (ID) and severe to profound global developmental delay (GDD). RESULTS: Nineteen patients were enrolled: 17 (89.5%) unrelated and 2 (10.5%) familial. Twelve (63.2%) were females. Developmental epileptic encephalopathy (DEE) was observed in 18 (94.7%) patients and ID alone in 1 (5.3%) individual. Thirteen patients (68.4%) had profound ID/GDD, 4 (23.53%) severe, 1 (5.9%) moderate and 1 (5.9%) mild. Three patients (15.8%) with profound ID died. A total of 19 variants were detected: pathogenic (n = 15) and likely pathogenic (n = 4). Seven were novel variants: c.664-1G>-, M486R, H245N, H498Pfs*44, L41R, L410del, and D90H. Of the 8 previous reported variants, 2 were recurrent: R406C and R292C. Anti-seizure medications were used in combinations, and 7 patients became seizure-free, and most of them achieved seizure freedom within the first 2 years of life irrespective of the type of the mutation. Effective medications for the seizure-free individuals included adrenocorticotropic (ACTH) and/or levetiracetam and/or phenobarbital and/or sodium valproate and/or topiramate and/or vigabatrin and/or nitrazepam. There was no correlation between the types of pathogenic variants and the phenotypes. CONCLUSION: Our case-series showed that there is no genotype-phenotype correlation in patients with STXBP1-related disorders. This study adds 7 novel variants which expand the spectrum of STXBP1-related disorders. Combinations of levetiracetam and/or sodium valproate and/or ACTH and/or phenobarbital and/or vigabatrin and/or topiramate and/or nitrazepam were more often associated with seizure freedom in our cohort within 2 years of life.


Assuntos
Estudos de Associação Genética , Deficiência Intelectual , Proteínas Munc18 , Nitrazepam , Feminino , Humanos , Masculino , Hormônio Adrenocorticotrópico , China , Levetiracetam , Proteínas Munc18/genética , Fenobarbital , Fenótipo , Estudos Retrospectivos , Topiramato , Ácido Valproico , Vigabatrina
18.
Eur J Med Chem ; 258: 115589, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37413884

RESUMO

The discovery and development of novel µ-opioid receptor (MOR) antagonists is a significant area to combat Opioid Use Disorder (OUD). In this work, a series of para-substituted N-cyclopropylmethyl-nornepenthone derivatives were designed and synthesized and pharmacologically assayed. Compound 6a was identified as a selective MOR antagonist both in vitro and in vivo. Its molecular basis was elucidated using molecular docking and MD simulations. A subpocket on the extracellular side of the TM2 domain of MOR, in particular the residue Y2.64, was proposed to be responsible for the reversal of subtype selectivity and functional reversal of this compound.


Assuntos
Morfinanos , Morfinanos/química , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Ligantes , Receptores Opioides mu , Antagonistas de Entorpecentes/farmacologia
19.
J Oncol ; 2022: 4689396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36111241

RESUMO

Background: The role of N6-methyladenosine long noncoding RNAs (lncRNAs) in colorectal cancer (CRC) is elusive. Materials and Methods: We identified m6A-associated lncRNAs by using the data gathered from The Cancer Genome Atlas (TCGA) and stratified CRC patients into different subgroups. Cox regression analysis was performed to construct an m6A-associated lncRNA signature. The role of this signature in the immune microenvironment and prognosis was dissected subsequently. Finally, a gene set enrichment analysis (GSEA) was conducted to predict the possible mechanisms based on the signature. Results: Three m6A-associated clusters were constructed from 866 differentially expressed lncRNAs. Cluster 2 had poor prognosis and low immune cell infiltration. An m6A-associated lncRNA signature consisting of 14 lncRNAs was constructed and recognized as an independent prognostic indicator of CRC by using survival analysis and receiver operating characteristic (ROC) curves. The clinical features and immune cell infiltration status were significantly different in patients stratified by the risk score. Furthermore, GSEA showed that the P53 pathway and natural killer cell-mediated cytotoxicity were more enriched in the low-risk group. Conclusion: Our data revealed that m6A-associated lncRNAs could be potential prognostic indicators of immunogenicity in CRC.

20.
Clin Chim Acta ; 524: 179-186, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34800434

RESUMO

BACKGROUND: Autism spectrum disorder (ASD), a neurodevelopmental disorder, is featured by impaired social communication and restricted and repetitive behaviors and interests. ASD and comorbid neurodevelopmental disorders (ASD-NDDs), especially epilepsy and intellectual disability (ID)/global developmental delay (GDD) are frequently presented in genetic disorders. The aim of this study was to explore the clinical and genetic profile of ASD in combination with epilepsy or ID/GDD. METHODS: We retrospectively analyzed the clinical characteristics, and genetic spectrum of pediatric patients presenting ASD-NDDs with proven genetic etiology. The pathogenicity of variants was conducted by molecular geneticists and clinicians complied with the guidelines of the American College of Medical Genetics and Genomics (ACMG). RESULTS: Among 154 patients with ASD-NDDs, 79 (51.3%) patients gained a genetic diagnosis. Most patients (78/79, 98.7%) had comorbid ID or GDD, and 49 (49/79, 62.0%) had comorbid epilepsy. The clinical characteristics of those 79 patients were varied. 87 genetic variants were found among the 79 pedigrees. Most of the involved genes have roles in gene expression regulation (GER) and neuronal communication (NC). Most genes have been proven to be ASD-related genes, and some of them were not reported to contribute to ASD previously. CONCLUSION: We summarized the genetic and clinical profile of 79 ASD-NDDs patients with proven genetic etiology. The genetic spectrum of ASD was expanded, and we highlighted a novel possible ASD candidate gene PRTG.


Assuntos
Transtorno do Espectro Autista , Deficiência Intelectual , Transtornos do Neurodesenvolvimento , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/epidemiologia , Transtorno do Espectro Autista/genética , Criança , Perfil Genético , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/epidemiologia , Deficiência Intelectual/genética , Transtornos do Neurodesenvolvimento/epidemiologia , Transtornos do Neurodesenvolvimento/genética , Estudos Retrospectivos
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