Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
J Am Chem Soc ; 146(9): 5952-5963, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38408428

RESUMO

The ability of alkylamines to spontaneously liberate hydride ions is typically restrained, except under specific intramolecular reaction settings. Herein, we demonstrate that this reactivity can be unlocked through simple treatment with formaldehyde in hexafluoroisopropanol (HFIP) solvent, thereby enabling various intermolecular hydride transfer reactions of alkylamines under mild conditions. Besides transformations of small molecules, these reactions enable unique late-stage modification of complex peptides. Mechanistic investigations uncover that the key to these intermolecular hydride transfer processes lies in the accommodating conformation of solvent-mediated macrocyclic transition states, where the aggregates of HFIP molecules act as dexterous proton shuttles. Importantly, negative hyperconjugation between the lone electron pair of nitrogen and the antibonding orbital of amine's α C-H bond plays a critical role in the C-H activation, promoting its hydride liberation.

2.
Exp Physiol ; 109(6): 956-965, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38643470

RESUMO

Traumatic brain injury (TBI) is a major cause of morbidity and mortality globally. We unveiled the diagnostic value of serum NLRP3, metalloproteinase-9 (MMP-9) and interferon-γ (IFN-γ) levels in post-craniotomy intracranial infections and hydrocephalus in patients with severe craniocerebral trauma to investigate the high risk factors for these in patients with TBI, and the serological factors predicting prognosis, which had a certain clinical predictive value. Study subjects underwent bone flap resection surgery and were categorized into the intracranial infection/hydrocephalus/control (without postoperative hydrocephalus or intracranial infection) groups, with their clinical data documented. Serum levels of NLRP3, MMP-9 and IFN-γ were determined using ELISA kits, with their diagnostic efficacy on intracranial infections and hydrocephalus evaluated by receiver operating characteristic curve analysis. The independent risk factors affecting postoperative intracranial infections and hydrocephalus were analysed by logistic multifactorial regression. The remission after postoperative symptomatic treatment was counted. The intracranial infection/control groups had significant differences in Glasgow Coma Scale (GCS) scores, opened injury, surgical time and cerebrospinal fluid leakage, whereas the hydrocephalus and control groups had marked differences in GCS scores, cerebrospinal fluid leakage and subdural effusion. Serum NLRP3, MMP-9 and IFN-γ levels were elevated in patients with post-craniotomy intracranial infections/hydrocephalus. The area under the curve values of independent serum NLRP3, MMP-9, IFN-γ and their combination for diagnosing postoperative intracranial infection were 0.822, 0.722, 0.734 and 0.925, respectively, and for diagnosing hydrocephalus were 0.865, 0.828, 0.782 and 0.957, respectively. Serum NLRP3, MMP-9 and IFN-γ levels and serum NLRP3 and MMP-9 levels were independent risk factors influencing postoperative intracranial infection and postoperative hydrocephalus, respectively. Patients with hydrocephalus had a high remission rate after postoperative symptomatic treatment. Serum NLRP3, MMP-9 and IFN-γ levels had high diagnostic efficacy in patients with postoperative intracranial infection and hydrocephalus, among which serum NLRP3 level played a major role.


Assuntos
Hidrocefalia , Interferon gama , Metaloproteinase 9 da Matriz , Proteína 3 que Contém Domínio de Pirina da Família NLR , Humanos , Masculino , Metaloproteinase 9 da Matriz/sangue , Feminino , Pessoa de Meia-Idade , Interferon gama/sangue , Adulto , Hidrocefalia/cirurgia , Traumatismos Craniocerebrais/complicações , Traumatismos Craniocerebrais/sangue , Complicações Pós-Operatórias/sangue , Idoso , Fatores de Risco , Biomarcadores/sangue , Adulto Jovem
3.
Phys Chem Chem Phys ; 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39158723

RESUMO

Although Mo2C and earth-abundant 3d transition metals are regarded as potential catalysts to replace noble metal catalysts for effective hydrogen evolution reaction, their large-scale application is still inhibited by their own defects. Here, a facile thermal treatment method for nonprecious metal catalysts is developed to prepare a porous Ni/Mo2C composite catalyst. The loading density of Ni nanoparticles on the Mo2C surface has an important effect on the activity of the catalyst. By optimizing the Ni doping ratio, the Ni-40/Mo2C-17 sample exhibits the lowest onset overpotential and lowest overpotential at 10 mA cm-2 in both acidic and alkaline electrolytes, compared to other reported Ni- and Mo2C-based catalysts. In addition, theoretical calculations have also confirmed the synergistic effect between Ni nanoparticles and Mo2C, which can balance the thermodynamics between H adsorption and desorption of H2. This work provides an avenue for designing high-performance water-splitting catalytic materials using low-cost species, which exhibit excellent HER activity in a wide pH range.

4.
Int J Med Sci ; 21(2): 277-283, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38169716

RESUMO

Objective: This study aimed to investigate the association between serum potassium variability and 60-day mortality and cardiovascular disease (CVD) in maintenance hemodialysis (MHD) patients following the coronavirus disease 2019 (COVID-19) infection. Methods: We conducted a retrospective study on MHD patients treated at the affiliated hospital of Qingdao University hemodialysis center who were infected with the novel coronavirus between December 1, 2022, and January 31, 2023. Baseline characteristics of patients were collected from electronic medical records. Kaplan-Meier survival analysis was used to obtain patient survival probabilities, and multivariate Cox hazard regression models and binary Logistic regression models were used to obtain hazard ratios (HR), odds ratios (OR), and 95% confidence intervals (95% CI) between exposure and outcomes. Results: A total of 296 patients were included in this study, with a mean age of 57.2±16.3 years, and 59.8% were male. The 60-day mortality rate was 10.8%, and the incidence of CVD was 32.8%. Kaplan-Meier curves showed that a higher potassium variability coefficient was associated with higher all-cause mortality (P = 0.024). After adjusting for potential confounders, multivariate Cox regression analysis showed that the HR for 60-day mortality in the Q4 group compared to the Q1 group was 2.06 (95% CI = 1.03-4.09, P = 0.040), and binary Logistic regression analysis showed that the OR for 60-day CVD in the Q4 group compared to the Q1 group was 4.09 (95% CI = 1.52-10.97, P = 0.005). Conclusion: Increased serum potassium variability in MHD patients after COVID-19 infection significantly increased the likelihood of 60-day mortality and CVD.


Assuntos
COVID-19 , Doenças Cardiovasculares , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Estudos Retrospectivos , COVID-19/complicações , Diálise Renal/efeitos adversos , Potássio
5.
J Liposome Res ; : 1-14, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101839

RESUMO

Micro-145 down-regulation is frequently found in breast cancers, indicating its potential as a therapeutic target. The introduction of exogenous miR-145 directly to the tumor sites has been a hurdle due to limited delivery, low bioavailability, and hence lower therapeutic efficacy. Thus, this study aims to synthesize and characterize PEGylated liposome co-loaded with Dox-HCl and miR-145 mimics to investigate its in-vitro anti-proliferative activity against MDA-MB-231 cells. The formulations were developed using a composite central design to optimize nanoparticle size and encapsulation efficiency (EE%) of Dox-HCl and miR-145 mimics. The optimized formulation exhibited the highest desirability function (D = 0.814) and displayed excellent stability over 60 days at 4 °C, maintaining a stable nanoparticle size and zeta potential, with relative EE% of Dox-HCl and miR-145 mimics on the final incubation day 94.97 ± 0.53% and 51.96 ± 2.67%, respectively. The system displayed a higher rate of drug release within 4 h of incubation at an acidic condition. Additionally, the optimized formulation demonstrated a higher toxicity (IC50 = 0.58 µM) against MDA-MB-231 cells than the free Dox- HCl and miR-145 regimen (IC50 = 1.00 µM). Our findings suggest that PEGylated liposome is tunable for effective concurrent delivery of anticancer drugs and therapeutic miRNAs into tumor cells, necessitating further investigation.

6.
J Pediatr Nurs ; 75: 31-40, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38101309

RESUMO

PROBLEM: Most rare diseases occur in childhood and are difficult to diagnose and treat. The caregivers are faced with the challenge of providing care to the children afflicted with these rare diseases, resulting in a significant burden of care and an altered family dynamic. ELIGIBILITY CRITERIA: A meta-synthesis review was conducted to explore the caregivers' experience of children with rare diseases using eight electronic databases PubMed, Web of Science, the Cochrane Library, EMBASE, VIP database, Wan Fang, Chinese BioMedical Literature Database, and China National Knowledge Infrastructure from each database's inception to October 5, 2023. SAMPLE: 4207 records were identified and 20 eligible studies were included. RESULTS: Three themes emerged: (1) Life is changed by "rare"; (2) many unmet needs; (3) Strive to adapt and grow. CONCLUSIONS: Caregivers of children with rare diseases are full of stress and challenges in the process of caring for them, and their lives have changed greatly due to "rare". Appropriate measures need to be taken to reduce the burden on caregivers. IMPLICATIONS: According to the findings, both the medical and health systems, as well as society, should pay attention to the care load and unmet requirements of carers of children with rare diseases, and offer them with practical supportive services. Finally, it can improve the quality of life for caregivers and families of children with rare diseases, as well as stimulate the development of rare diseases.


Assuntos
Cuidadores , Qualidade de Vida , Criança , Humanos , Pesquisa Qualitativa , Doenças Raras
7.
Zhongguo Zhong Yao Za Zhi ; 49(12): 3132-3143, 2024 Jun.
Artigo em Zh | MEDLINE | ID: mdl-39041073

RESUMO

The traditional Chinese medicine(TCM) single preparation refers to the innovative TCM made from the whole or the effective part(including the effective ingredient) extract of a TCM single herb by modern technology. They have a long history of applications, definite effects and few side effects. It is an indispensable part of the research of innovative TCM. In recent years, with the optimization of national policies, the development of TCM single preparation shows a positive trend. However, because of the imbalance in the composition ratio, the need for expansion of indications, the need for further basic research, and the low conversion rate of existing patent achievements in universities and institutes, the TCM single preparation still has significant development space. In this review, we analyze and study the current situation, characteristics and difficulties of TCM single preparation, as well as relevant clinical application, basic research, industrialization and patent application information through statistical analysis of TCM single preparations in the Chinese Pharmacopoeia, which helps to provide direction for the development and research of single preparation of TCM.


Assuntos
Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/química , Humanos
8.
Angew Chem Int Ed Engl ; 63(16): e202318893, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38376389

RESUMO

α-Ketoaldehydes play versatile roles in the ubiquitous natural processes of protein glycation. However, leveraging the reactivity of α-ketoaldehydes for biomedical applications has been challenging. Previously, the reactivity of α-ketoaldehydes with guanidine has been harnessed to design probes for labeling Arg residues on proteins in an aqueous medium. Herein, a highly effective, broadly applicable, and operationally simple protocol for stapling native peptides by crosslinking two amino groups through diverse imidazolium linkers with various α-ketoaldehyde reagents is described. The use of hexafluoroisopropanol as a solvent facilitates rapid and clean reactions under mild conditions and enables unique selectivity for Lys over Arg. The naturally occurring GOLD/MOLD linkers have been expanded to encompass a wide range of modified glyoxal-lysine dimer (OLD) linkers. In a proof-of-concept trial, these modular stapling reactions enabled a convenient two-round strategy to streamline the structure-activity relationship (SAR) study of the wasp venom peptide anoplin, leading to enhanced biological activities.


Assuntos
Glioxal , Lisina , Glioxal/química , Lisina/química , Aminas , Aldeídos , Peptídeos , Reagentes de Ligações Cruzadas/química
9.
Zhongguo Zhong Yao Za Zhi ; 48(23): 6324-6333, 2023 Dec.
Artigo em Zh | MEDLINE | ID: mdl-38211989

RESUMO

Chronic heart failure(CHF) is a comprehensive clinical syndrome caused by multiple factors that result in structural and/or functional abnormalities of the heart, leading to impaired ventricular contraction and/or relaxation functions. This medical condition represents the final stage of various cardiovascular diseases. In the treatment of CHF, multiple clinical studies have demonstrated the benefits of using traditional Chinese medicine(TCM) to control oxidative stress, inflammation, and apoptosis, thereby delaying ventricular remodeling and reducing myocardial fibrosis. In this study, common TCM syndromes in the diagnosis and treatment of CHF in recent years were reviewed and summarized. Five common treatment methods including benefiting Qi and activating blood circulation, enhancing Qi and nourishing Yin, warming Yang for diuresis, eliminating phlegm and dampness, rescuing from collapse by restoring Yang, and corresponding classic prescriptions in prevention and treatment of CHF were concluded under the guidance of TCM syndrome differentiation thinking. Meanwhile, research progress on the modern pharmacological effects of these classic prescriptions was systematically discussed, so as to establish a unique treatment system for CHF by classic prescriptions under the guidance of TCM syndrome differentiation theory and provide innovative diagnosis and treatment strategies for clinical CHF.


Assuntos
Insuficiência Cardíaca , Medicina Tradicional Chinesa , Humanos , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/tratamento farmacológico , Doença Crônica , Síndrome
10.
IEEE Trans Biomed Eng ; 71(8): 2454-2462, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38470574

RESUMO

Some classification studies of brain-computer interface (BCI) based on speech imagery show potential for improving communication skills in patients with amyotrophic lateral sclerosis (ALS). However, current research on speech imagery is limited in scope and primarily focuses on vowels or a few selected words. In this paper, we propose a complete research scheme for multi-character classification based on EEG signals derived from speech imagery. Firstly, we record 31 speech imagery contents, including 26 alphabets and five commonly used punctuation marks, from seven subjects using a 32-channel electroencephalogram (EEG) device. Secondly, we introduce the wavelet scattering transform (WST), which shares a structural resemblance to Convolutional Neural Networks (CNNs), for feature extraction. The WST is a knowledge-driven technique that preserves high-frequency information and maintains the deformation stability of EEG signals. To reduce the dimensionality of wavelet scattering coefficient features, we employ Kernel Principal Component Analysis (KPCA). Finally, the reduced features are fed into an Extreme Gradient Boosting (XGBoost) classifier within a multi-classification framework. The XGBoost classifier is optimized through hyperparameter tuning using grid search and 10-fold cross-validation, resulting in an average accuracy of 78.73% for the multi-character classification task. We utilize t-Distributed Stochastic Neighbor Embedding (t-SNE) technology to visualize the low-dimensional representation of multi-character speech imagery. This visualization effectively enables us to observe the clustering of similar characters. The experimental results demonstrate the effectiveness of our proposed multi-character classification scheme. Furthermore, our classification categories and accuracy exceed those reported in existing research.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Processamento de Sinais Assistido por Computador , Fala , Humanos , Eletroencefalografia/métodos , Fala/fisiologia , Algoritmos , Análise de Ondaletas , Imaginação/fisiologia , Adulto , Masculino , Feminino , Redes Neurais de Computação
11.
Mol Neurobiol ; 61(9): 6312-6327, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38296899

RESUMO

Heat stroke (HS) is a severe medical condition characterized by a systemic inflammatory response that may precipitate multi-organ dysfunction, with a particular predilection for inducing profound central nervous system impairments. We aim to employ bioinformatics techniques for the retrieval and analysis of genes associated with heat stroke-induced neurological damage. We performed a comprehensive analysis of the GSE64778 dataset from the Sequence Read Archive, resulting in the identification of 1178 significantly differentially expressed genes (DEGs). We retrieved 2914 genes associated with heat stroke from the GeneCards database and 2377 genes associated with heat stroke from the Comparative Toxicogenomics Database (CTD). The intersection of the top 300 DEGs in the GSE64778 dataset intersected with the search results of GeneCards and CTD, yielding 25 final candidates for DEGs associated with heat stroke. Gene Ontology functional annotation results indicated that the target genes were mainly involved in apoptosis, stress response, and negative regulation of cellular processes and function in processes such as protein dimerization and protein binding. The Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis revealed a predominant enrichment of candidate target genes within the PI3K-AKT signaling pathway. Subsequent protein-protein interaction network analysis highlighted HSP90aa1 as a central gene, indicating its pivotal role by possessing the highest number of edges among the genes enriched in the PI3K-AKT signaling pathway. Quantitative reverse transcription-polymerase chain reaction analysis performed on blood samples from patients validated the expression of Hsp90aa1 in individuals exhibiting early neurological damage in HS, consistent with the findings from the mRNA bioinformatics analysis. Additionally, the bioinformatics analysis of the upstream microRNAs (miRNAs) regulating HSP90aa1 and the target miRNAs associated with candidate long non-coding RNAs (lncRNAs) identified three lncRNAs, eight miRNAs, and one mRNA in the regulatory network. The DIANA Tools database and algorithms were employed for pathway enrichment and correlation analysis, revealing a significant association between LOC102547734 and MIR-206-3p, with the latter being identified as a target binding site Moreover, the analysis unveiled a correlation between MIR-206-3p and HSP90aa1, implicating the latter as a potential target binding site within the regulatory network.


Assuntos
Ontologia Genética , Golpe de Calor , Golpe de Calor/genética , Humanos , Mapas de Interação de Proteínas/genética , Proteínas de Choque Térmico HSP90/genética , Redes Reguladoras de Genes , Perfilação da Expressão Gênica , Bases de Dados Genéticas , Biologia Computacional/métodos , Estudos de Associação Genética , Transdução de Sinais/genética , Reprodutibilidade dos Testes
12.
Signal Transduct Target Ther ; 9(1): 37, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38360862

RESUMO

The human gastrointestinal tract is populated with a diverse microbial community. The vast genetic and metabolic potential of the gut microbiome underpins its ubiquity in nearly every aspect of human biology, including health maintenance, development, aging, and disease. The advent of new sequencing technologies and culture-independent methods has allowed researchers to move beyond correlative studies toward mechanistic explorations to shed light on microbiome-host interactions. Evidence has unveiled the bidirectional communication between the gut microbiome and the central nervous system, referred to as the "microbiota-gut-brain axis". The microbiota-gut-brain axis represents an important regulator of glial functions, making it an actionable target to ameliorate the development and progression of neurodegenerative diseases. In this review, we discuss the mechanisms of the microbiota-gut-brain axis in neurodegenerative diseases. As the gut microbiome provides essential cues to microglia, astrocytes, and oligodendrocytes, we examine the communications between gut microbiota and these glial cells during healthy states and neurodegenerative diseases. Subsequently, we discuss the mechanisms of the microbiota-gut-brain axis in neurodegenerative diseases using a metabolite-centric approach, while also examining the role of gut microbiota-related neurotransmitters and gut hormones. Next, we examine the potential of targeting the intestinal barrier, blood-brain barrier, meninges, and peripheral immune system to counteract glial dysfunction in neurodegeneration. Finally, we conclude by assessing the pre-clinical and clinical evidence of probiotics, prebiotics, and fecal microbiota transplantation in neurodegenerative diseases. A thorough comprehension of the microbiota-gut-brain axis will foster the development of effective therapeutic interventions for the management of neurodegenerative diseases.


Assuntos
Doenças Neurodegenerativas , Probióticos , Humanos , Encéfalo/metabolismo , Doenças Neurodegenerativas/terapia , Doenças Neurodegenerativas/metabolismo , Eixo Encéfalo-Intestino , Probióticos/uso terapêutico , Prebióticos
13.
Nat Commun ; 15(1): 4493, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802342

RESUMO

Abscisic acid (ABA) plays a crucial role in promoting plant stress resistance and seed dormancy. However, how ABA regulates rice quality remains unclear. This study identifies a key transcription factor SLR1-like2 (SLRL2), which mediates the ABA-regulated amylose content (AC) of rice. Mechanistically, SLRL2 interacts with NF-YB1 to co-regulate Wx, a determinant of AC and rice quality. In contrast to SLR1, SLRL2 is ABA inducible but insensitive to GA. In addition, SLRL2 exhibits DNA-binding activity and directly regulates the expression of Wx, bHLH144 and MFT2. SLRL2 competes with NF-YC12 for interaction with NF-YB1. NF-YB1 also directly represses SLRL2 transcription. Genetic validation supports that SLRL2 functions downstream of NF-YB1 and bHLH144 in regulating rice AC. Thus, an NF-YB1-SLRL2-bHLH144 regulatory module is successfully revealed. Furthermore, SLRL2 regulates rice dormancy by modulating the expression of MFT2. In conclusion, this study revealed an ABA-responsive regulatory cascade that functions in both rice quality and seed dormancy.


Assuntos
Ácido Abscísico , Regulação da Expressão Gênica de Plantas , Oryza , Dormência de Plantas , Proteínas de Plantas , Oryza/genética , Oryza/metabolismo , Ácido Abscísico/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Dormência de Plantas/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Fator de Ligação a CCAAT/metabolismo , Fator de Ligação a CCAAT/genética , Sementes/metabolismo , Sementes/crescimento & desenvolvimento , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Amilose/metabolismo , Grão Comestível/metabolismo , Grão Comestível/genética , Plantas Geneticamente Modificadas
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa