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1.
Nat Immunol ; 24(4): 676-689, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36914891

RESUMO

Mature T cells must discriminate between brief interactions with self-peptides and prolonged binding to agonists. The kinetic proofreading model posits that certain T-cell antigen receptor signaling nodes serve as molecular timers to facilitate such discrimination. However, the physiological significance of this regulatory mechanism and the pathological consequences of disrupting it are unknown. Here we report that accelerating the normally slow phosphorylation of the linker for activation of T cells (LAT) residue Y136 by introducing an adjacent Gly135Asp alteration (LATG135D) disrupts ligand discrimination in vivo. The enhanced self-reactivity of LATG135D T cells triggers excessive thymic negative selection and promotes T-cell anergy. During Listeria infection, LATG135D T cells expand more than wild-type counterparts in response to very weak stimuli but display an imbalance between effector and memory responses. Moreover, despite their enhanced engagement of central and peripheral tolerance mechanisms, mice bearing LATG135D show features associated with autoimmunity and immunopathology. Our data reveal the importance of kinetic proofreading in balancing tolerance and immunity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Linfócitos T , Camundongos , Animais , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Substituição de Aminoácidos , Receptores de Antígenos de Linfócitos T/metabolismo , Ativação Linfocitária , Fosforilação , Fosfoproteínas/genética
2.
Nat Immunol ; 20(11): 1481-1493, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31611699

RESUMO

Self-non-self discrimination is central to T cell-mediated immunity. The kinetic proofreading model can explain T cell antigen receptor (TCR) ligand discrimination; however, the rate-limiting steps have not been identified. Here, we show that tyrosine phosphorylation of the T cell adapter protein LAT at position Y132 is a critical kinetic bottleneck for ligand discrimination. LAT phosphorylation at Y132, mediated by the kinase ZAP-70, leads to the recruitment and activation of phospholipase C-γ1 (PLC-γ1), an important effector molecule for T cell activation. The slow phosphorylation of Y132, relative to other phosphosites on LAT, is governed by a preceding glycine residue (G131) but can be accelerated by substituting this glycine with aspartate or glutamate. Acceleration of Y132 phosphorylation increases the speed and magnitude of PLC-γ1 activation and enhances T cell sensitivity to weaker stimuli, including weak agonists and self-peptides. These observations suggest that the slow phosphorylation of Y132 acts as a proofreading step to facilitate T cell ligand discrimination.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Ativação Linfocitária , Proteínas de Membrana/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/imunologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Animais , Feminino , Ligantes , Masculino , Proteínas de Membrana/imunologia , Camundongos , Fosfolipase C gama/metabolismo , Fosforilação/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Linfócitos T/metabolismo , Tirosina/metabolismo , Proteína-Tirosina Quinase ZAP-70/metabolismo
3.
Nat Immunol ; 19(7): 733-741, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29915297

RESUMO

T cell-antigen receptor (TCR) signaling requires the sequential activities of the kinases Lck and Zap70. Upon TCR stimulation, Lck phosphorylates the TCR, thus leading to the recruitment, phosphorylation, and activation of Zap70. Lck binds and stabilizes phosho-Zap70 by using its SH2 domain, and Zap70 phosphorylates the critical adaptors LAT and SLP76, which coordinate downstream signaling. It is unclear whether phosphorylation of these adaptors occurs through passive diffusion or active recruitment. We report the discovery of a conserved proline-rich motif in LAT that mediates efficient LAT phosphorylation. Lck associates with this motif via its SH3 domain, and with phospho-Zap70 via its SH2 domain, thereby acting as a molecular bridge that facilitates the colocalization of Zap70 and LAT. Elimination of this proline-rich motif compromises TCR signaling and T cell development. These results demonstrate the remarkable multifunctionality of Lck, wherein each of its domains has evolved to orchestrate a distinct step in TCR signaling.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteína Tirosina Quinase p56(lck) Linfócito-Específica/metabolismo , Proteínas de Membrana/metabolismo , Proteína-Tirosina Quinase ZAP-70/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/química , Motivos de Aminoácidos , Animais , Células HEK293 , Humanos , Células Jurkat , Proteínas de Membrana/química , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Prolina/análise , Receptores de Antígenos de Linfócitos T/metabolismo , Timo/imunologia
4.
Nature ; 631(8022): 867-875, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38987588

RESUMO

Chronic hepatitis B virus (HBV) infection affects 300 million patients worldwide1,2, in whom virus-specific CD8 T cells by still ill-defined mechanisms lose their function and cannot eliminate HBV-infected hepatocytes3-7. Here we demonstrate that a liver immune rheostat renders virus-specific CD8 T cells refractory to activation and leads to their loss of effector functions. In preclinical models of persistent infection with hepatotropic viruses such as HBV, dysfunctional virus-specific CXCR6+ CD8 T cells accumulated in the liver and, as a characteristic hallmark, showed enhanced transcriptional activity of cAMP-responsive element modulator (CREM) distinct from T cell exhaustion. In patients with chronic hepatitis B, circulating and intrahepatic HBV-specific CXCR6+ CD8 T cells with enhanced CREM expression and transcriptional activity were detected at a frequency of 12-22% of HBV-specific CD8 T cells. Knocking out the inhibitory CREM/ICER isoform in T cells, however, failed to rescue T cell immunity. This indicates that CREM activity was a consequence, rather than the cause, of loss in T cell function, further supported by the observation of enhanced phosphorylation of protein kinase A (PKA) which is upstream of CREM. Indeed, we found that enhanced cAMP-PKA-signalling from increased T cell adenylyl cyclase activity augmented CREM activity and curbed T cell activation and effector function in persistent hepatic infection. Mechanistically, CD8 T cells recognizing their antigen on hepatocytes established close and extensive contact with liver sinusoidal endothelial cells, thereby enhancing adenylyl cyclase-cAMP-PKA signalling in T cells. In these hepatic CD8 T cells, which recognize their antigen on hepatocytes, phosphorylation of key signalling kinases of the T cell receptor signalling pathway was impaired, which rendered them refractory to activation. Thus, close contact with liver sinusoidal endothelial cells curbs the activation and effector function of HBV-specific CD8 T cells that target hepatocytes expressing viral antigens by means of the adenylyl cyclase-cAMP-PKA axis in an immune rheostat-like fashion.


Assuntos
Linfócitos T CD8-Positivos , Hepatite B Crônica , Fígado , Animais , Humanos , Masculino , Camundongos , Linfócitos T CD8-Positivos/enzimologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Modulador de Elemento de Resposta do AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Vírus da Hepatite B/imunologia , Hepatite B Crônica/imunologia , Hepatite B Crônica/virologia , Hepatócitos/imunologia , Hepatócitos/virologia , Fígado/imunologia , Fígado/virologia , Fosforilação , Transdução de Sinais , Ativação Linfocitária
6.
Proc Natl Acad Sci U S A ; 121(30): e2407159121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012820

RESUMO

Mutations in the tyrosine phosphatase Src homology-2 domain-containing protein tyrosine phosphatase-2 (SHP2) are associated with a variety of human diseases. Most mutations in SHP2 increase its basal catalytic activity by disrupting autoinhibitory interactions between its phosphatase domain and N-terminal SH2 (phosphotyrosine recognition) domain. By contrast, some disease-associated mutations located in the ligand-binding pockets of the N- or C-terminal SH2 domains do not increase basal activity and likely exert their pathogenicity through alternative mechanisms. We lack a molecular understanding of how these SH2 mutations impact SHP2 structure, activity, and signaling. Here, we characterize five SHP2 SH2 domain ligand-binding pocket mutants through a combination of high-throughput biochemical screens, biophysical and biochemical measurements, and molecular dynamics simulations. We show that while some of these mutations alter binding affinity to phosphorylation sites, the T42A mutation in the N-SH2 domain is unique in that it also substantially alters ligand-binding specificity, despite being 8 to 10 Å from the specificity-determining region of the SH2 domain. This mutation exerts its effect on sequence specificity by remodeling the phosphotyrosine-binding pocket, altering the mode of engagement of both the phosphotyrosine and surrounding residues on the ligand. The functional consequence of this altered specificity is that the T42A mutant has biased sensitivity toward a subset of activating ligands and enhances downstream signaling. Our study highlights an example of a nuanced mechanism of action for a disease-associated mutation, characterized by a change in protein-protein interaction specificity that alters enzyme activation.


Assuntos
Simulação de Dinâmica Molecular , Proteína Tirosina Fosfatase não Receptora Tipo 11 , Domínios de Homologia de src , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/química , Humanos , Domínios de Homologia de src/genética , Ligação Proteica , Mutação , Fosforilação , Sítios de Ligação/genética , Fosfotirosina/metabolismo , Ligantes
7.
Brief Bioinform ; 25(4)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38801701

RESUMO

Spatially resolved transcriptomics data are being used in a revolutionary way to decipher the spatial pattern of gene expression and the spatial architecture of cell types. Much work has been done to exploit the genomic spatial architectures of cells. Such work is based on the common assumption that gene expression profiles of spatially adjacent spots are more similar than those of more distant spots. However, related work might not consider the nonlocal spatial co-expression dependency, which can better characterize the tissue architectures. Therefore, we propose MuCoST, a Multi-view graph Contrastive learning framework for deciphering complex Spatially resolved Transcriptomic architectures with dual scale structural dependency. To achieve this, we employ spot dependency augmentation by fusing gene expression correlation and spatial location proximity, thereby enabling MuCoST to model both nonlocal spatial co-expression dependency and spatially adjacent dependency. We benchmark MuCoST on four datasets, and we compare it with other state-of-the-art spatial domain identification methods. We demonstrate that MuCoST achieves the highest accuracy on spatial domain identification from various datasets. In particular, MuCoST accurately deciphers subtle biological textures and elaborates the variation of spatially functional patterns.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Perfilação da Expressão Gênica/métodos , Humanos , Algoritmos , Aprendizado de Máquina , Biologia Computacional/métodos
8.
Nat Immunol ; 15(3): 266-74, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24487322

RESUMO

Interactions of T cell antigen receptors (TCRs) with complexes of self peptide and major histocompatibility complex (MHC) are crucial to T cell development, but their role in peripheral T cell responses remains unclear. Specific and nonspecific stimulation of LLO56 and LLO118 T cells, which transgenically express a TCR specific for the same Listeria monocytogenes epitope, elicited distinct interleukin 2 (IL-2) and phosphorylated kinase Erk responses, the strength of which was set in the thymus and maintained in the periphery in proportion to the avidity of the binding of the TCR to the self peptide-MHC complex. Deprivation of self peptide-MHC substantially compromised the population expansion of LLO56 T cells in response to L. monocytogenes in vivo. Despite their very different self-reactivity, LLO56 T cells and LLO118 T cells bound cognate peptide-MHC with an identical affinity, which challenges associations made between these parameters. Our findings highlight a crucial role for selecting ligands encountered during thymic 'education' in determining the intrinsic functionality of CD4+ T cells.


Assuntos
Autoantígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Ativação Linfocitária/imunologia , Complexo Principal de Histocompatibilidade/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Transferência Adotiva , Animais , Separação Celular , Citometria de Fluxo , Humanos , Immunoblotting , Listeriose/imunologia , Camundongos , Camundongos Knockout , Ressonância de Plasmônio de Superfície , Timo/citologia , Timo/imunologia , Transfecção
10.
Immunol Rev ; 307(1): 145-160, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34923645

RESUMO

Establishing both central and peripheral tolerance requires the appropriate TCR signaling strength to discriminate self- from agonist-peptide bound to self MHC molecules. ZAP70, a cytoplasmic tyrosine kinase, directly interacts with the TCR complex and plays a central and requisite role in TCR signaling in both thymocytes and peripheral T cells. By studying ZAP70 hypomorphic mutations in mice and humans with a spectrum of hypoactive or hyperactive activities, we have gained insights into mechanisms of central and peripheral tolerance. Interestingly, both hypoactive and hyperactive ZAP70 can lead to the development of autoimmune diseases, albeit through distinct mechanisms. Immature thymocytes and mature T cells rely on normal ZAP70 function to complete their development in the thymus and to modulate T cell responses in the periphery. Hypoactive ZAP70 function compromises key developmental checkpoints required to establish central tolerance, allowing thymocytes with potentially self-reactive TCRs a greater chance to escape negative selection. Such 'forbidden clones' may escape into the periphery and may pose a greater risk for autoimmune disease development since they may not engage negative regulatory mechanisms as effectively. Hyperactive ZAP70 enhances thymic negative selection but some thymocytes will, nonetheless, escape negative selection and have greater sensitivity to weak and self-ligands. Such cells must be controlled by mechanisms involved in anergy, expansion of Tregs, and upregulation of inhibitory receptors or signaling molecules. However, such potentially autoreactive cells may still be able to escape control by peripheral negative regulatory constraints. Consistent with findings in Zap70 mutants, the signaling defects in at least one ZAP70 substrate, LAT, can also lead to autoimmune disease. By dissecting the similarities and differences among mouse models of patient disease or mutations in ZAP70 that affect TCR signaling strength, we have gained insights into how perturbed ZAP70 function can lead to autoimmunity. Because of our work and that of others on ZAP70, it is likely that perturbations in other molecules affecting TCR signaling strength will be identified that also overcome tolerance mechanisms and cause autoimmunity. Delineating these molecular pathways could lead to the development of much needed new therapeutic targets in these complex diseases.


Assuntos
Doenças Autoimunes , Autoimunidade , Proteínas Tirosina Quinases/metabolismo , Animais , Humanos , Tolerância Imunológica , Camundongos , Receptores de Antígenos de Linfócitos T/metabolismo , Timócitos , Timo
11.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-37950877

RESUMO

Autism spectrum disorder (ASD) is characterized by etiological and phenotypic heterogeneity. Despite efforts to categorize ASD into subtypes, research on specific functional connectivity changes within ASD subgroups based on clinical presentations is limited. This study proposed a symptom-based clustering approach to identify subgroups of ASD based on multiple clinical rating scales and investigate their distinct Electroencephalogram (EEG) functional connectivity patterns. Eyes-opened resting-state EEG data were collected from 72 children with ASD and 63 typically developing (TD) children. A data-driven clustering approach based on Social Responsiveness Scales-Second Edition and Vinland-3 scores was used to identify subgroups. EEG functional connectivity and topological characteristics in four frequency bands were assessed. Two subgroups were identified: mild ASD (mASD, n = 37) and severe ASD (sASD, n = 35). Compared to TD, mASD showed increased functional connectivity in the beta band, while sASD exhibited decreased connectivity in the alpha band. Significant between-group differences in global and regional topological abnormalities were found in both alpha and beta bands. The proposed symptom-based clustering approach revealed the divergent functional connectivity patterns in the ASD subgroups that was not observed in typical ASD studies. Our study thus provides a new perspective to address the heterogeneity in ASD research.


Assuntos
Transtorno do Espectro Autista , Criança , Humanos , Transtorno do Espectro Autista/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Eletroencefalografia , Análise por Conglomerados , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Mapeamento Encefálico
12.
Med Res Rev ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38769656

RESUMO

Oncogenes and tumor suppressors are well-known to orchestrate several signaling cascades, regulate extracellular and intracellular stimuli, and ultimately control the fate of cancer cells. Accumulating evidence has recently revealed that perturbation of these key modulators by mutations or abnormal protein expressions are closely associated with drug resistance in cancer therapy; however, the inherent drug resistance or compensatory mechanism remains to be clarified for targeted drug discovery. Thus, dual-target drug development has been widely reported to be a promising therapeutic strategy for improving drug efficiency or overcoming resistance mechanisms. In this review, we provide an overview of the therapeutic strategies of dual-target drugs, especially focusing on pharmacological small-molecule compounds in cancer, including small molecules targeting mutation resistance, compensatory mechanisms, synthetic lethality, synergistic effects, and other new emerging strategies. Together, these therapeutic strategies of dual-target drugs would shed light on discovering more novel candidate small-molecule drugs for the future cancer treatment.

13.
Brief Bioinform ; 23(3)2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35368055

RESUMO

The rapid development of single-cell DNA sequencing (scDNA-seq) technology has greatly enhanced the resolution of tumor cell profiling, providing an unprecedented perspective in characterizing intra-tumoral heterogeneity and understanding tumor progression and metastasis. However, prominent algorithms for constructing tumor phylogeny based on scDNA-seq data usually only take single nucleotide variations (SNVs) as markers, failing to consider the effect caused by copy number alterations (CNAs). Here, we propose BiTSC$^2$, Bayesian inference of Tumor clonal Tree by joint analysis of Single-Cell SNV and CNA data. BiTSC$^2$ takes raw reads from scDNA-seq as input, accounts for the overlapping of CNA and SNV, models allelic dropout rate, sequencing errors and missing rate, as well as assigns single cells into subclones. By applying Markov Chain Monte Carlo sampling, BiTSC$^2$ can simultaneously estimate the subclonal scCNA and scSNV genotype matrices, subclonal assignments and tumor subclonal evolutionary tree. In comparison with existing methods on synthetic and real tumor data, BiTSC$^2$ shows high accuracy in genotype recovery, subclonal assignment and tree reconstruction. BiTSC$^2$ also performs robustly in dealing with scDNA-seq data with low sequencing depth and variant missing rate. BiTSC$^2$ software is available at https://github.com/ucasdp/BiTSC2.


Assuntos
Neoplasias , Algoritmos , Teorema de Bayes , Variações do Número de Cópias de DNA , Humanos , Neoplasias/genética , Análise de Sequência de DNA , Software
14.
Nat Immunol ; 13(9): 880-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22842345

RESUMO

The sustained entry of Ca(2+) into CD4(+)CD8(+) double-positive thymocytes is required for positive selection. Here we identified a voltage-gated Na(+) channel (VGSC) that was essential for positive selection of CD4(+) T cells. Pharmacological inhibition of VGSC activity inhibited the sustained Ca(2+) influx induced by positively selecting ligands and the in vitro positive selection of CD4(+) but not CD8(+) T cells. In vivo short hairpin RNA (shRNA)-mediated knockdown of the gene encoding a regulatory ß-subunit of a VGSC specifically inhibited the positive selection of CD4(+) T cells. Ectopic expression of VGSC in peripheral AND CD4(+) T cells bestowed the ability to respond to a positively selecting ligand, which directly demonstrated that VGSC expression was responsible for the enhanced sensitivity. Thus, active VGSCs in thymocytes provide a mechanism by which a weak positive selection signal can induce the sustained Ca(2+) signals required for CD4(+) T cell development.


Assuntos
Linfócitos T CD4-Positivos/citologia , Diferenciação Celular/imunologia , Canais de Sódio/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Citometria de Fluxo , Humanos , Ativação do Canal Iônico , Camundongos , Camundongos Transgênicos , Canal de Sódio Disparado por Voltagem NAV1.5 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Subunidade beta-4 do Canal de Sódio Disparado por Voltagem
15.
Eur Radiol ; 34(2): 842-851, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37606664

RESUMO

OBJECTIVES: To explore the use of deep learning-constrained compressed sensing (DLCS) in improving image quality and acquisition time for 3D MRI of the brachial plexus. METHODS: Fifty-four participants who underwent contrast-enhanced imaging and forty-one participants who underwent unenhanced imaging were included. Sensitivity encoding with an acceleration of 2 × 2 (SENSE4x), CS with an acceleration of 4 (CS4x), and DLCS with acceleration of 4 (DLCS4x) and 8 (DLCS8x) were used for MRI of the brachial plexus. Apparent signal-to-noise ratios (aSNRs), apparent contrast-to-noise ratios (aCNRs), and qualitative scores on a 4-point scale were evaluated and compared by ANOVA and the Friedman test. Interobserver agreement was evaluated by calculating the intraclass correlation coefficients. RESULTS: DLCS4x achieved higher aSNR and aCNR than SENSE4x, CS4x, and DLCS8x (all p < 0.05). For the root segment of the brachial plexus, no statistically significant differences in the qualitative scores were found among the four sequences. For the trunk segment, DLCS4x had higher scores than SENSE4x (p = 0.04) in the contrast-enhanced group and had higher scores than SENSE4x and DLCS8x in the unenhanced group (all p < 0.05). For the divisions, cords, and branches, DLCS4x had higher scores than SENSE4x, CS4x, and DLCS8x (all p ≤ 0.01). No overt difference was found among SENSE4x, CS4x, and DLCS8x in any segment of the brachial plexus (all p > 0.05). CONCLUSIONS: In three-dimensional MRI for the brachial plexus, DLCS4x can improve image quality compared with SENSE4x and CS4x, and DLCS8x can maintain the image quality compared to SENSE4x and CS4x. CLINICAL RELEVANCE STATEMENT: Deep learning-constrained compressed sensing can improve the image quality or accelerate acquisition of 3D MRI of the brachial plexus, which should be benefit in evaluating the brachial plexus and its branches in clinical practice. KEY POINTS: •Deep learning-constrained compressed sensing showed higher aSNR, aCNR, and qualitative scores for the brachial plexus than SENSE and CS at the same acceleration factor with similar scanning time. •Deep learning-constrained compressed sensing at acceleration factor of 8 had comparable aSNR, aCNR, and qualitative scores to SENSE4x and CS4x with approximately half the examination time. •Deep learning-constrained compressed sensing may be helpful in clinical practice for improving image quality and acquisition time in three-dimensional MRI of the brachial plexus.


Assuntos
Plexo Braquial , Aprendizado Profundo , Humanos , Imageamento Tridimensional/métodos , Plexo Braquial/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Razão Sinal-Ruído
16.
J Pineal Res ; 76(1): e12922, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37909654

RESUMO

This was a prospective, randomized, double-blind, single-center placebo-controlled trial to assess the efficacy and safety of melatonin as an add-on treatment for infantile epileptic spasms syndrome (IESS). Participants aged 3 months to 2 years with a primary diagnosis of IESS were recruited and assigned to two groups in a 1:1 ratio. Both treatment groups received a combination of adrenocorticotrophic hormone (ACTH) and magnesium sulfate (MgSO4 ) for 2 weeks, and the treatment group also received melatonin (3 mg) between 20:00 and 21:00 daily, 0.5-1 h before bedtime. The study's primary endpoint was the average reduction rate in spasm frequency assessed by seizure diaries. Secondary endpoints included assessment of the response rate, EEG hypsarrhythmia (Kramer score), and psychomotor development (Denver Developmental Screening Test, DDST). Sleep quality was assessed by using the Brief Infant Sleep Questionnaire (BISQ), the Infant Sleep Assessment Scale (ISAS), and actigraphy. Safety parameters were also evaluated. Statistical analyses were conducted on intention-to-treat and per-protocol populations. The trial is registered at Clinicaltrials.gov (ChiCTR2000036208). Out of 119 screened patients, 70 were randomized and 66 completed treatments. In the intention-to-treat population, there were no significant differences in the average percentage reduction of spasm frequency (median [interquartile range, IQR: Q3-Q1], 100% [46.7%] vs. 66.7% [55.3%], p = .288), the 3-day response rate (51.4% vs. 37.1%, p = .229), the 28-day response rate (42.9% vs. 28.6%, p = .212), EEG Kramer scores (2 [3.5] vs. 2 [3], p = .853), or DDST comprehensive months (5 [2.5] vs. 6 [6], p = .239) between the melatonin (n = 35) and placebo (n = 35) groups. However, caregivers reported improved sleep quality after melatonin treatment, with 85.7% reporting regular sleep compared to 42.9% with placebo (42.9%, p < .001). The melatonin group had lower ISAS scores in 4-11-month-old patients compared to the placebo (mean ± SD, 29.3 ± 4.4 vs. 35.2 ± 5.9, p < .001). Moreover, the median (IQR) value of sleep-onset latency was shortened by 6.0 (24.5) min after melatonin treatment, while that in the placebo group was extended by 3.0 (22.0) min (p = .030). The serum melatonin (6:00 h) level (pg/mL) of the children in the melatonin group after treatment was significantly higher than in the placebo group (median [IQR], 84.8 [142] vs. 17.5 [37.6], p < .001). No adverse effects related to melatonin were observed in the study, and there were no significant differences in adverse effects between the melatonin and placebo groups. Although not statistically significant, the results of this randomized clinical trial proved that melatonin supplementation, as an add-on treatment, can improve spasm control rate in the treatment of IESS. For IESS children treated with ACTH, the addition of melatonin was found to improve sleep quality, shorten sleep onset latency, and increase blood melatonin levels. Moreover, it was observed to be a safe treatment option.


Assuntos
Melatonina , Criança , Humanos , Lactente , Melatonina/uso terapêutico , Estudos Prospectivos , Hormônio Adrenocorticotrópico/uso terapêutico , Método Duplo-Cego , Espasmo/tratamento farmacológico , Suplementos Nutricionais
17.
J Nat Prod ; 87(5): 1479-1486, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38728656

RESUMO

Bioinspired skeleton transformation of a tricyclic lathyrane-type Euphorbia diterpene was conducted to efficiently construct a tetracyclic tigliane diterpene on a gram scale via a key aldol condensation. The tigliane diterpene was then respectively converted into naturally rare ingenane and rhamnofolane diterpenes through a semipinacol rearrangement and a visible-light-promoted regioselective cyclopropane ring-opening reaction. This work provides a concise strategy for high-efficiency access to diverse polycyclic Euphorbia diterpene skeletons from abundant lathyrane-type natural products and paves the way for biological activity investigation of naturally rare molecules.


Assuntos
Diterpenos , Euphorbia , Diterpenos/química , Diterpenos/isolamento & purificação , Euphorbia/química , Estrutura Molecular , Biomimética , Produtos Biológicos/química
18.
Artigo em Inglês | MEDLINE | ID: mdl-38430167

RESUMO

Background: The advent of immunotherapy has revolutionized non-small cell lung cancer (NSCLC) treatment. Anlotinib (AN), a multitargeted tyrosine kinase inhibitor, holds promise in combination with PD-1 monoclonal antibody therapy. Understanding the impact of optimal dosage is pivotal. Objective: This study aims to assess the comparative efficacy of high-dose AN versus low-dose AN when combined with PD-1 monoclonal antibody for the treatment of NSCLC. Methods: A total of 70 patients with NSCLC undergoing PD-1 monoclonal antibody therapy at our hospital from June 2020 to January 2022 were selected. The low-dose group (n=33) received AN at 8 mg and 10 mg. In comparison, the high-dose group (n=37) received AN at 12 mg. Comparative analyses included assessment of clinical efficacy, adverse reactions, prognosis, survival, changes in T lymphocyte subsets, inflammatory factors pre and post-chemotherapy, and treatment satisfaction. Results: No significant difference was observed in clinical efficacy and prognosis between the two groups (P > .05). The low-dose group exhibited fewer adverse reactions and inflammatory responses, along with improved immune function post-treatment (P < .05). Treatment satisfaction was higher in the low-dose group compared to the high-dose group (P < .05). Conclusions: Findings suggest that combining low-dose AN with PD-1 monoclonal antibody therapy is a safer approach in the treatment of advanced NSCLC. These findings advocate for the adoption of a tailored, lower-dose AN regimen, presenting a clinically sound and patient-centered strategy in the ongoing pursuit of optimized treatment modalities for advanced NSCLC.

19.
Artigo em Inglês | MEDLINE | ID: mdl-39083170

RESUMO

Women who undergo cesarean delivery have reported experiencing mood distress related to the surgery and postoperative pain. Heart rate variability biofeedback (HRVB) training is known to have positive effects on mental health, but its effects on women undergoing cesarean delivery have not yet been determined. This study evaluated the effects of an HRVB training intervention on stress, anxiety, and depression in women undergoing cesarean delivery. We hypothesized that 10 sessions of HRVB training could cumulatively improve emotion regulation in participants. This study was designed as a double-blinded randomized controlled trial involving a total of 86 enrolled women who were then divided into two groups: intervention and control. During their hospitalization, the intervention group underwent HRVB training daily, while both groups received standard perinatal care. Heart rate variability (HRV) was assessed using root mean square of successive differences (RMSSD), standard deviation of normal-to-normal intervals (SDNN), high-frequency power (HF) and low-frequency power (LF). HRV parameters, stress, anxiety, and depression were evaluated at baseline and on the fifth day after childbirth. Intention-to-treat (ITT) analyses examined change over time between groups. Although no significant effects were found for the RMSSD and HF, a significant increase was observed in SDNN (F = 13.43, p = < 0.001, ƞ2 = 0.14), and LF at post-assessment (F = 4.26, p = .04, ƞ2 = 0.05) compared to the control group. Except for the depression variable, stress (F = 6.11, p = .02, ƞ2 = 0.07) and anxiety (F = 8.78, p = .004, ƞ2 = 0.10) significantly decreased compared to the control group on the fifth postpartum day. Furthermore, post-hoc analysis showed that HRVB was more effective in decreasing mild to severe depressive symptoms (F = 7.60, p = .001, ƞ2 = 0.27). The intervention program successfully decreased self-perceived stress and anxiety in the postpartum period and relieved symptoms in more severely depressed participants. Our findings suggest that this program is suitable and beneficial for application in women during the early postpartum period following cesarean delivery.

20.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(6): 725-729, 2024 Jun 10.
Artigo em Zh | MEDLINE | ID: mdl-38818558

RESUMO

OBJECTIVE: To investigate the clinical features and genetic variant of a child with West syndrome due to a variant of NEXMIF gene. METHODS: A child who was admitted to the First Medical Center of Chinese PLA General Hospital in March 2021 was selected as the study subject. Clinical data of the patient was collected. The child and his parents were subjected to whole exome sequencing. Candidate variant was verified by Sanger sequencing and pathogenicity analysis. RESULTS: The child, a 4-month-old boy, had presented with spastic seizures with no obvious cause. Abnormal EEG, severe hypsarrhythmia, and multiple spastic seizures were discovered. Cranial MRI revealed widening of the extracerebral space at the top of the frontal lobe. Physical examination revealed that the child could not hold his head up, and could not respond to sounds or follow objects with his eyes. He also has microcephaly, with height < 1 s. The child was diagnosed with West syndrome at a local hospital, and was given prednisone orally for 3 months, with seizures under control. Topiramate tablets were taken orally for maintenance treatment, and he has been seizure-free for 7 months. DNA sequencing revealed that he has harbored a de novo nonsense variant of c.982_c.983delTT (p.L328Dfs*23) in the NEXMIF gene. CONCLUSION: For children with West syndrome with severe developmental delay or even regression as the first symptoms, uncontrollable seizures and abnormal facial appearance, mutations of the NEXMIF gene should be suspected, and genetic testing can facilitate early diagnosis and treatment.


Assuntos
Espasmos Infantis , Humanos , Masculino , Lactente , Espasmos Infantis/genética , Mutação , Sequenciamento do Exoma , Testes Genéticos
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