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1.
J Clin Invest ; 134(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38557493

RESUMO

Metabolic dysfunction-associated steatohepatitis (MASH) - previously described as nonalcoholic steatohepatitis (NASH) - is a major driver of liver fibrosis in humans, while liver fibrosis is a key determinant of all-cause mortality in liver disease independent of MASH occurrence. CCAAT/enhancer binding protein α (CEBPA), as a versatile ligand-independent transcriptional factor, has an important function in myeloid cells, and is under clinical evaluation for cancer therapy. CEBPA is also expressed in hepatocytes and regulates glucolipid homeostasis; however, the role of hepatocyte-specific CEBPA in modulating liver fibrosis progression is largely unknown. Here, hepatic CEBPA expression was found to be decreased during MASH progression both in humans and mice, and hepatic CEBPA mRNA was negatively correlated with MASH fibrosis in the human liver. CebpaΔHep mice had markedly enhanced liver fibrosis induced by a high-fat, high-cholesterol, high-fructose diet or carbon tetrachloride. Temporal and spatial hepatocyte-specific CEBPA loss at the progressive stage of MASH in CebpaΔHep,ERT2 mice functionally promoted liver fibrosis. Mechanistically, hepatocyte CEBPA directly repressed Spp1 transactivation to reduce the secretion of osteopontin, a fibrogenesis inducer of hepatic stellate cells. Forced hepatocyte-specific CEBPA expression reduced MASH-associated liver fibrosis. These results demonstrate an important role for hepatocyte-specific CEBPA in liver fibrosis progression, and may help guide the therapeutic discoveries targeting hepatocyte CEBPA for the treatment of liver fibrosis.


Assuntos
Proteína alfa Estimuladora de Ligação a CCAAT , Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Hepatócitos/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Fígado/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Modelos Animais de Doenças
2.
Disabil Rehabil ; : 1-15, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38638087

RESUMO

PURPOSE: This review systematically explores and summarise the effects of motor imagery training (MIT) compared to conventional therapy on gait performance in individuals after stroke. MATERIALS AND METHODS: Randomised controlled trials (RCTs) were systematically searched in five electronic databases (PubMed, EMBASE, PsycINFO, OVID Nursing and CINAHL) from inception to 30 December 2022. Studies investigating MITs, targeted at individuals after stroke were eligible. Data were extracted related to study and intervention characteristics. RESULTS: Sixteen studies were included. Compared with 'routine methods of treatment or training', the meta-analyses showed that MIT was more effective in improving cadence immediately post intervention (SMD: 1.22, 95% CI: 0.59, 1.85, p = 0.0001, I2 = 25%) and at 1- or 2-months post intervention (SMD: 0.78, 95% CI: 0.35, 1.20, p = 0.0004, I2 = 46%). The results also showed that MIT improves the step length of the affected side and the unaffected side at 1- or 2-months post intervention. Separate meta-analyses were also conducted on different tests of walking endurance (assessed by the 6-Minute Walk Test) and functional mobility (assessed by the Timed-Up-and-Go test). CONCLUSIONS: MIT effectively improved gait performance. The findings in individuals after stroke remain inconclusive due to significant heterogeneity in included studies.


Restoring gait performance and daily functional abilities is an important goal of post-stroke rehabilitation.Motor imagery training (MIT) may be a promising method to improve gait restoration and is expected to provide another option for the effective rehabilitation of stroke patients.This review highlights the limited research on MIT and thus the limited evidence to guide clinical rehabilitation.In the stroke rehabilitation, clinical specialists may consider incorporating MIT into the treatment programme to improve patients' gait performance and ensure effective early lower limb rehabilitation.

4.
J Exp Bot ; 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38497815

RESUMO

The 2-(2-phenethyl)chromones (PECs) are the signature constituents responsible for the fragrance and pharmacological properties of agarwood. O-methyltransferases (OMTs) are necessary for the methylated PECs biosynthesis, however, there is little information known about OMTs in Aquilaria sinensis. In this study, we identified 29 OMT genes from the A. sinensis genome. Expression analysis showed they were differentially expressed in different tissues and responded to drill wounding. Comprehensive analysis of the gene expression and methylated PECs content revealed that the AsOMT2, AsOMT8, AsOMT11, AsOMT16, and AsOMT28 could potentially be involved in methylated PECs biosynthesis. The vitro enzyme assays and functional analysis in Nicotiana benthamiana demonstrated that AsOMT11 and AsOMT16 could methylate 6-hydroxy-2-(2-phenylethyl)chromone to form 6-methoxy-2-(2-phenylethyl) chromone. The transient overexpression experiment in Qi-Nan revealed that AsOMT11 and AsOMT16 could significantly promote the accumulation of three major methylated PECs. Our results provide candidate genes for the mass production of methylated PECs using synthetic biology.

5.
Fitoterapia ; 175: 105901, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38467281

RESUMO

To compare the bioactive compounds in agarwood induced by different methods in Aquilaria sinensis(Lour.) Gilg trees, a two dimensional thin layer chromatograph(2D-TLC) combined with effect directive analysis(EDA) was developed. Three antioxidants were found by 2D-TLC-DPPH and further identified as 2-(2-phenylethyl) chromones(PECs) with LC-MS/MS. The 3 antioxidants decreased along agarwood formation and their compositions in drilling induced agarwood differed with those in microbe culture induced agarwood. Further study showed NaCl treatment promoted antioxidants accumulation in agarwood induced by drilling or hot drilling. Hot drilling combined with salty stimulation was most efficient in some chemicals accumulation, which were identified as PECs with antioxidant, tyrosinase or ß-glucosidase inhibiting activities by 2D-TLC-EDA-LC-MS/MS. This study provided a 2D-TLC-EDA-LC-MS/MS method for bioactive compounds screen and qualification of agarwood. Based on this method, non-conventional methods were found to accelerate the accumulation of some bioactive PECs in A. sinensis trees.

6.
Int J Biol Macromol ; 261(Pt 2): 129908, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38320642

RESUMO

An alcohol-induced liver injury model was induced in C57BL/6 mice to assess the protective efficacy of Enteromorpha prolifera polysaccharides (EP) against liver damage. Histological alterations in the liver were examined following hematoxylin-eosin (H&E) staining. Biochemical assay kits and ELISA kits were employed to analyze serum and liver biochemical parameters, as well as the activity of antioxidant enzymes and alcohol metabolism-related enzymes. The presence of oxidative stress-related proteins in the liver was detected using western blotting. Liquid chromatography and mass spectrometry were used to profile serum metabolites in mice. The findings demonstrated that EP-H (100 mg/Kg) reduced serum ALT and AST activity by 2.31-fold and 2.32-fold, respectively, when compared to the alcohol-induced liver injury group. H&E staining revealed a significant attenuation of microvesicular steatosis and ballooning pathology in the EP-H group compared to the model group. EP administration was found to enhance alcohol metabolism by regulating metabolite-related enzymes (ADH and ALDH) and decreasing CYP2E1 expression. EP also modulated the Nrf2/HO-1 signaling pathway to bolster hepatic antioxidant capacity. Furthermore, EP restored the levels of lipid metabolites (Glycine, Butanoyl-CoA, and Acetyl-CoA) to normalcy. In summary, EP confers protection to the liver through the regulation of antioxidant activity and lipid metabolites in the murine liver.


Assuntos
Antioxidantes , Doença Hepática Crônica Induzida por Substâncias e Drogas , Algas Comestíveis , Ulva , Camundongos , Animais , Antioxidantes/farmacologia , Doença Hepática Crônica Induzida por Substâncias e Drogas/patologia , Camundongos Endogâmicos C57BL , Fígado , Estresse Oxidativo , Etanol/farmacologia , Polissacarídeos/farmacologia , Polissacarídeos/química , Lipídeos/farmacologia
7.
Nature ; 626(8000): 859-863, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38326609

RESUMO

Bacteria in the gastrointestinal tract produce amino acid bile acid amidates that can affect host-mediated metabolic processes1-6; however, the bacterial gene(s) responsible for their production remain unknown. Herein, we report that bile salt hydrolase (BSH) possesses dual functions in bile acid metabolism. Specifically, we identified a previously unknown role for BSH as an amine N-acyltransferase that conjugates amines to bile acids, thus forming bacterial bile acid amidates (BBAAs). To characterize this amine N-acyltransferase BSH activity, we used pharmacological inhibition of BSH, heterologous expression of bsh and mutants in Escherichia coli and bsh knockout and complementation in Bacteroides fragilis to demonstrate that BSH generates BBAAs. We further show in a human infant cohort that BBAA production is positively correlated with the colonization of bsh-expressing bacteria. Lastly, we report that in cell culture models, BBAAs activate host ligand-activated transcription factors including the pregnane X receptor and the aryl hydrocarbon receptor. These findings enhance our understanding of how gut bacteria, through the promiscuous actions of BSH, have a significant role in regulating the bile acid metabolic network.


Assuntos
Aciltransferases , Amidoidrolases , Aminas , Ácidos e Sais Biliares , Biocatálise , Microbioma Gastrointestinal , Humanos , Aciltransferases/metabolismo , Amidoidrolases/metabolismo , Aminas/química , Aminas/metabolismo , Bacteroides fragilis/enzimologia , Bacteroides fragilis/genética , Bacteroides fragilis/metabolismo , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Estudos de Coortes , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/metabolismo , Microbioma Gastrointestinal/fisiologia , Ligantes , Receptor de Pregnano X/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Fatores de Transcrição/metabolismo , Lactente , Técnicas de Cultura de Células
8.
Mar Drugs ; 22(2)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38393028

RESUMO

Oxidative stress, which damages cellular components and causes mitochondrial dysfunction, occurs in a variety of human diseases, including neurological disorders. The clearance of damaged mitochondria via mitophagy maintains the normal function of mitochondria and facilitates cell survival. Astaxanthin is an antioxidant known to have neuroprotective effects, but the underlying mechanisms remain unclear. This study demonstrated that astaxanthin inhibited H2O2-induced apoptosis in SH-SY5Y cells by ameliorating mitochondrial damage and enhancing cell survival. H2O2 treatment significantly reduced the levels of activated Akt and mTOR and induced mitophagy, while pretreatment with astaxanthin prevented H2O2-induced inhibition of Akt and mTOR and attenuated H2O2-induced mitophagy. Moreover, the inhibition of Akt attenuated the protective effect of astaxanthin against H2O2-induced cytotoxicity. Taken together, astaxanthin might inhibit H2O2-induced apoptosis by protecting mitochondrial function and reducing mitophagy. The results also indicate that the Akt/mTOR signaling pathway was critical for the protection of astaxanthin against H2O2-induced cytotoxicity. The results from the present study suggest that astaxanthin can reduce neuronal oxidative injury and may have the potential to be used for preventing neurotoxicity associated with neurodegenerative diseases.


Assuntos
Neuroblastoma , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Peróxido de Hidrogênio/toxicidade , Mitofagia , Neuroblastoma/tratamento farmacológico , Apoptose , Estresse Oxidativo , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Espécies Reativas de Oxigênio/metabolismo , Xantofilas
9.
Physiol Int ; 111(1): 35-46, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38261006

RESUMO

Objective: Gastric cancer is the most frequent gastrointestinal malignancy with a poor prognosis. Rac GTPase activation protein 1 (RACGAP1) is a novel tumor promotor, whose detailed effect on gastric cancer remains to be further elucidated. Hence, this study identifies the action of RACGAP1 on gastric cancer and investigates the potential mechanism. Methods: RACGAP1 expression in gastric cancer was analyzed based on the data of The Cancer Genome Atlas (TCGA) database. Cell proliferation was measured by CCK-8 and colony formation assay. Cell migration and invasion were evaluated by transwell assay. Cell apoptosis was assessed by flow cytometry. Cell autophagy was evaluated via determining LC3. Results: RACGAP1 presented at high level in gastric cancer cells. Overexpressed RACGAP1 potentiated gastric cancer cell proliferation, migration, and invasion. Besides, silenced RACGAP1 induced cell apoptosis and autophagy. Furthermore, RACGAP1 suppressed the expression of SIRT1 and Mfn2. Conclusion: RACGAP1 was overexpressed in gastric cancer. RACGAP1 potentiated aggressive behaviors of gastric cancer, and suppressed cell apoptosis and autophagy via modulating SIRT1/Mfn2. RACGAP1 may be a valuable target in the treatment of gastric cancer.


Assuntos
Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Sirtuína 1/genética , Proliferação de Células , Autofagia , Linhagem Celular Tumoral
10.
Heart Lung Circ ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38242833

RESUMO

AIM: With the advancement of anti-cancer medicine, cardiovascular toxicities due to cancer therapies are common in oncology patients, resulting in increased mortality and economic burden. Cardiovascular toxicities caused by cancer therapies include different severities of cardiomyopathy, arrhythmia, myocardial ischaemia, hypertension, and thrombosis, which may lead to left ventricular dysfunction and heart failure. This scoping review aimed to summarise the mechanisms of cardiovascular toxicities following various anti-cancer treatments and potential predictive biomarkers for early detection. METHODS: PubMed, Cochrane, Embase, Web of Science, Scopus, and CINAHL databases were searched for original studies written in English related to the mechanisms of cardiovascular toxicity induced by anti-cancer therapies, including chemotherapy, targeted therapy, immunotherapy, radiation therapy, and relevant biomarkers. The search and title/abstract screening were conducted independently by two reviewers, and the final analysed full texts achieved the consensus of the two reviewers. RESULTS: A total of 240 studies were identified based on their titles and abstracts. In total, 107 full-text articles were included in the analysis. Cardiomyocyte and endothelial cell apoptosis caused by oxidative stress injury, activation of cell apoptosis, blocking of normal cardiovascular protection signalling pathways, overactivation of immune cells, and myocardial remodelling were the main mechanisms. Promising biomarkers for anti-cancer therapies related to cardiovascular toxicity included placental growth factor, microRNAs, galectin-3, and myeloperoxidase for the early detection of cardiovascular toxicity. CONCLUSION: Understanding the mechanisms of cardiovascular toxicity following various anti-cancer treatments could provide implications for future personalised treatment methods to protect cardiovascular function. Furthermore, specific early sensitive and stable biomarkers of cardiovascular system damage need to be identified to predict reversible damage to the cardiovascular system and improve the effects of anti-cancer agents.

11.
Proc Natl Acad Sci U S A ; 121(6): e2317408121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38285953

RESUMO

Light plays a central role in plant growth and development, providing an energy source and governing various aspects of plant morphology. Previous study showed that many polyadenylated full-length RNA molecules within the nucleus contain unspliced introns (post-transcriptionally spliced introns, PTS introns), which may play a role in rapidly responding to changes in environmental signals. However, the mechanism underlying post-transcriptional regulation during initial light exposure of young, etiolated seedlings remains elusive. In this study, we used FLEP-seq2, a Nanopore-based sequencing technique, to analyze nuclear RNAs in Arabidopsis (Arabidopsis thaliana) seedlings under different light conditions and found numerous light-responsive PTS introns. We also used single-nucleus RNA sequencing (snRNA-seq) to profile transcripts in single nucleus and investigate the distribution of light-responsive PTS introns across distinct cell types. We established that light-induced PTS introns are predominant in mesophyll cells during seedling de-etiolation following exposure of etiolated seedlings to light. We further demonstrated the involvement of the splicing-related factor A. thaliana PROTEIN ARGININE METHYLTRANSFERASE 5 (AtPRMT5), working in concert with the E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1), a critical repressor of light signaling pathways. We showed that these two proteins orchestrate light-induced PTS events in mesophyll cells and facilitate chloroplast development, photosynthesis, and morphogenesis in response to ever-changing light conditions. These findings provide crucial insights into the intricate mechanisms underlying plant acclimation to light at the cell-type level.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteína-Arginina N-Metiltransferases , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Plântula/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Luz
12.
Nature ; 626(7998): 419-426, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38052229

RESUMO

Determining the structure and phenotypic context of molecules detected in untargeted metabolomics experiments remains challenging. Here we present reverse metabolomics as a discovery strategy, whereby tandem mass spectrometry spectra acquired from newly synthesized compounds are searched for in public metabolomics datasets to uncover phenotypic associations. To demonstrate the concept, we broadly synthesized and explored multiple classes of metabolites in humans, including N-acyl amides, fatty acid esters of hydroxy fatty acids, bile acid esters and conjugated bile acids. Using repository-scale analysis1,2, we discovered that some conjugated bile acids are associated with inflammatory bowel disease (IBD). Validation using four distinct human IBD cohorts showed that cholic acids conjugated to Glu, Ile/Leu, Phe, Thr, Trp or Tyr are increased in Crohn's disease. Several of these compounds and related structures affected pathways associated with IBD, such as interferon-γ production in CD4+ T cells3 and agonism of the pregnane X receptor4. Culture of bacteria belonging to the Bifidobacterium, Clostridium and Enterococcus genera produced these bile amidates. Because searching repositories with tandem mass spectrometry spectra has only recently become possible, this reverse metabolomics approach can now be used as a general strategy to discover other molecules from human and animal ecosystems.


Assuntos
Amidas , Ácidos e Sais Biliares , Ésteres , Ácidos Graxos , Metabolômica , Animais , Humanos , Bifidobacterium/metabolismo , Ácidos e Sais Biliares/química , Ácidos e Sais Biliares/metabolismo , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Clostridium/metabolismo , Estudos de Coortes , Doença de Crohn/metabolismo , Enterococcus/metabolismo , Ésteres/química , Ésteres/metabolismo , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Metabolômica/métodos , Fenótipo , Receptor de Pregnano X/metabolismo , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem , Amidas/química , Amidas/metabolismo
13.
Environ Sci Technol ; 57(50): 21470-21482, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38050842

RESUMO

NOx and CH3SH as two typical air pollutants widely coexist in various energy and industrial processes; hence, it is urgent to develop highly efficient catalysts to synergistically eliminate NOx and CH3SH. However, the catalytic system for synergistically eliminating NOx and CH3SH is seldom investigated to date. Meanwhile, the deactivation effects of CH3SH on catalysts and the formation mechanism of toxic byproducts emitted from the synergistic catalytic elimination reaction are still vague. Herein, selective synergistic catalytic elimination (SSCE) of NOx and CH3SH via engineering deep oxidation sites over Cu-modified Nb-Fe composite oxides supported on TiO2 catalyst against toxic CO and HCN byproducts formation has been originally demonstrated. Various spectroscopic and microscopic characterizations demonstrate that the sufficient chemisorbed oxygen species induced by the persistent electron transfer from Nb-Fe composite oxides to copper oxides can deeply oxidize HCOOH to CO2 for avoiding highly toxic byproducts formation. This work is of significance in designing superior catalysts employed in more complex working conditions and sheds light on the progress in the SSCE of NOx and sulfur-containing volatile organic compounds.


Assuntos
Poluentes Atmosféricos , Óxidos , Oxirredução , Óxidos/análise , Óxidos/química , Oxigênio , Transporte de Elétrons , Catálise , Amônia/química
14.
Food Chem Toxicol ; 182: 114129, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37967785

RESUMO

Chronic alcohol abuse causes brain damage and has been associated with an increased risk of Alzheimer's disease. The toxic metabolite of alcohol, acetaldehyde, which is converted to acetate by aldehyde dehydrogenase 2 (ALDH2), has been shown to induce excessive mitochondrial fragmentation and dysfunction leading to neurotoxicity. However, it is still unclear how alcohol affects mitochondrial function in ALDH2-deficient cells. The present study investigated the association between abnormal mitochondrial dynamics, mitophagy and cytotoxicity in ALDH2-deficient N2a cells treated with ethanol. It was found that ethanol induced dynamin-related protein 1 (Drp1)-mediated mitochondrial fragmentation and impaired mitochondrial function, causing excessive mitophagy and cytotoxicity in ALDH2-deficient N2a cells while inducing Ca2+ influx and activating Ca2+/calmodulin-dependent protein kinase II (CaMKII). Inhibition of Ca2+ overload or CaMKII activation prevented Drp1 phosphorylation and ameliorated ethanol-induced mitophagy and cytotoxicity, indicating that Ca2+-dependent CaMKII activation was critical for mediating Drp1-dependent excessive mitochondrial fission and mitophagy in ALDH2-deficient N2a cells. The results of the present study suggested that prevention of intracellular Ca2+ overload might be beneficial for preventing neurotoxicity associated with alcohol abuse in individuals with defective ALDH2.


Assuntos
Alcoolismo , Etanol , Humanos , Etanol/toxicidade , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Alcoolismo/complicações , Mitofagia , Dinaminas/genética , Dinaminas/metabolismo , Aldeído Desidrogenase , Aldeído-Desidrogenase Mitocondrial/genética
15.
Front Neurol ; 14: 1163094, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37840940

RESUMO

Introduction: Stroke is a major cause of death and disability worldwide, and it often results in depression, anxiety, stress, and cognitive impairment in survivors. There is a lack of community-based cognitive interventions for stroke survivors. This pilot single trial aimed to assess the feasibility, acceptability, and perceived effectiveness of a community-based cognitive intervention program called Train-Your-Brain (TYB) for stroke survivors and caregivers. The study focused on improvements in emotional and psychological well-being, as well as cognitive functioning. Methods: A quasi-experimental design was used in this study. A total of 48 participants were recruited and assessed using Depression, Anxiety, Stress Scale - 21 items (DASS-21), Montreal Cognitive Assessment (MoCA) and Symbol Digits Modality Test (SDMT) before and after the intervention. The TYB program consisted of nine sessions and was conducted via the Zoom software application. Participants provided feedback on the program, highlighting areas for improvement. Results: Twenty-seven stroke survivors and 21 caregivers completed the program. Participants expressed high satisfaction with the TYB program but recommended avoiding assessments in December and customizing the program for stroke survivors and caregivers. Stroke survivors showed significant improvements in depression and stress scores, while caregivers experienced no significant improvements after the program. While there was a slight improvement in stroke survivors' cognitive scores after the program, it was not statistically significant. Caregivers, however, experienced a significant decline in cognitive scores. Discussion: The TYB program provided group support and validation, resulting in improved mood and reduced stress among stroke survivors. Cultural collectivism played a significant role in fostering group cohesion. However, the program's limited focus on caregivers and timing of assessments during the December holidays may have affected the outcomes. The TYB program demonstrated feasibility and potential effectiveness in alleviating psychological distress and enhancing cognitive function among stroke survivors. Future research should explore long-term effects, larger sample sizes, and non-English-speaking populations to enhance generalizability. Tailored interventions for caregivers are necessary.

16.
Anal Chem ; 95(42): 15707-15715, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37818979

RESUMO

The chemical complexity of biological tissues creates challenges in the analysis of lipids via imaging mass spectrometry. The presence of isobaric and isomeric compounds introduces chemical noise that makes it difficult to unambiguously identify and accurately map the spatial distributions of these compounds. Electron-induced dissociation (EID) has previously been shown to profile phosphatidylcholine (PCs) sn-isomers directly from rat brain tissue in matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry. However, the acquisition of true pixel-by-pixel images, as opposed to regional profiling measurements, using EID is difficult due to low fragmentation efficiency and precursor ion signal dilution into multiple fragment ion channels, resulting in low sensitivity. In this work, we have developed a sequential collision-induced dissociation (CID)/EID method to visualize the distribution of sn-isomers in MALDI imaging mass spectrometry experiments. Briefly, CID is performed on sodium-adducted PCs, which results in facile loss of the phosphocholine headgroup. This ion is then subjected to an EID analysis. Since the lipid headgroup is removed prior to EID, a major fragmentation pathway common to EID ion activation is eliminated, resulting in a more sensitive analysis. This sequential CID/EID workflow generates sn-specific fragment ions allowing for the assignment of the sn-positions. Carbon-carbon double-bond (C═C) positions are also localized along the fatty acyl tails by the presence of a 2 Da shift pattern in the fragment ions arising from carbon-carbon bond cleavages. Moreover, the integration of the CID/EID method into MALDI imaging mass spectrometry enables the mapping of the absolute and relative distribution of sn-isomers at every pixel. The localized relative abundances of sn-isomers vary throughout brain substructures and likely reflect different biological functions and metabolism.


Assuntos
Elétrons , Fosfatidilcolinas , Ratos , Animais , Íons/química , Encéfalo , Carbono
17.
Toxins (Basel) ; 15(9)2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37755968

RESUMO

Previous experimental investigations have established the indispensability of the C-terminal Lys-Arg residues in the toxic activity of the AapA1 toxin protein. AapA1 is classified as a type I toxin-antitoxin (TA) bacterial toxin, and the precise impact of the C-terminal Lys-Arg residues on its structure and mechanism of action remains elusive. To address this knowledge gap, the present study employed molecular dynamics (MD) and enhanced sampling Well-tempered Two-dimensional Metadynamics (2D-MetaD) simulations to examine the behavior of the C-terminal Lys-Arg residues of truncated AapA1 toxin (AapA1-28) within the inner membrane of Escherichia coli. Specifically, the study focused on the elucidation of possible conformation states of AapA1-28 protein in POPE/POPG (3:1) bilayers and their interactions between the protein and POPE/POPG (3:1) bilayers. The findings of our investigation indicate that the AapA1-28 protein does not adopt a vertical orientation upon membrane insertion; rather, it assumes an angled conformation, with the side chain of Lys-23 directed toward the upper layer of the membrane. This non-transmembrane conformation of AapA1-28 protein impedes its ability to form pores within the membrane, resulting in reduced toxicity towards Escherichia coli. These results suggest that C-Terminal positively charged residues are essential for electrostatic binding to the negatively charged head group of bottom bilayer membrane, which stabilize the transmembrane conformation. These outcomes contribute to our comprehension of the impact of C-terminal charged residues on the structure and functionality of membrane-associated proteins, and provide an improved understanding of how protein sequence influences the antimicrobial effect.


Assuntos
Antitoxinas , Proteínas de Membrana , Sequência de Aminoácidos , Escherichia coli , Eletricidade Estática
18.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(9): 1142-1148, 2023 Sep 15.
Artigo em Chinês | MEDLINE | ID: mdl-37718429

RESUMO

Objective: To investigate the preparation and properties of the novel silica (SiO 2)/hydroxyapatite (HAP) whiskers porous ceramics scaffold. Methods: The HAP whiskers were modified by the SiO 2 microspheres using the Stöber method. Three types of SiO 2/HAP whiskers were fabricated under different factors (for the No.1 samples, the content of tetraethoxysilane, stirring time, calcination temperature, and soaking time were 10 mL, 12 hours, 560℃, and 0.5 hours, respectively; and in the No.2 samples, those were 15 mL, 24 hours, 650℃, and 2 hours, respectively; while those in the No.3 samples were 20 mL, 48 hours, 750℃, and 4 hours, respectively). The phase and morphology of the self-made HAP whisker and 3 types of SiO 2/HAP whiskers were detected by the X-ray diffraction analysis and scanning electron microscopy. Taken the self-made HAP whisker and 3 types of SiO 2/HAP whiskers as raw materials, various porous ceramic materials were prepared using the mechanical foaming method combined with extrusion molding method, and the low-temperature heat treatment. The pore structure of porous ceramics was observed by scanning electron microscopy. Its porosity and pore size distribution were measured. And further the axial compressive strength was measured, and the biodegradability was detected by simulated body fluid. Cell counting kit 8 method was used to conduct cytotoxicity experiments on the extract of porous ceramics. Results: The SiO 2 microspheres modified HAP whiskers and its porous ceramic materials were prepared successfully, respectively. In the SiO 2/HAP whiskers, the amorphous SiO 2 microspheres with a diameter of 200 nm, uniform distribution and good adhesion were attached to the surface of the whiskers, and the number of microspheres was controllable. The apparent porosity of the porous ceramic scaffold was about 78%, and its pore structure was composed of neatly arranged longitudinal through-holes and a large number of micro/nano through-holes. Compared with HAP whisker porous ceramic, the axial compressive strength of the SiO 2/HAP whisker porous ceramics could reach 1.0 MPa, which increased the strength by nearly 4 times. Among them, the axial compressive strength of the No.2 SiO 2/HAP whisker porous ceramic was the highest. The SiO 2 microspheres attached to the surface of the whiskers could provide sites for the deposition of apatite. With the content of SiO 2 microspheres increased, the deposition rate of apatite accelerated. The cytotoxicity level of the prepared porous ceramics ranged from 0 to 1, without cytotoxicity. Conclusion: SiO 2/HAP whisker porous ceramics have good biological activity, high porosity, three-dimensional complex pore structure, good axial compressive strength, and no cytotoxicity, which make it a promising scaffold material for bone tissue engineering.


Assuntos
Durapatita , Vibrissas , Animais , Porosidade , Apatitas , Cerâmica , Dióxido de Silício
19.
BMJ Open ; 13(9): e066931, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37709319

RESUMO

OBJECTIVES: To assess the association between maternal characteristics, adverse birth outcomes (small-for-gestational-age (SGA) and/or preterm) and neonatal mortality in rural Nepal. DESIGN: This is a secondary observational analysis to identify risk factors for neonatal mortality, using data from a randomised trial to assess the impact of newborn massage with different oils on neonatal mortality in Sarlahi district, Nepal. SETTING: Rural Sarlahi district, Nepal. PARTICIPANTS: 40 119 pregnant women enrolled from 9 September 2010 to 16 January 2017. MAIN OUTCOME: The outcome variable is neonatal death. Cox regression was used to estimate adjusted Hazard Ratios (aHRs) to assess the association between adverse birth outcomes and neonatal mortality. RESULTS: There were 32 004 live births and 998 neonatal deaths. SGA and/or preterm birth was strongly associated with increased neonatal mortality: SGA and preterm (aHR: 7.09, 95% CI: (4.44 to 11.31)), SGA and term/post-term (aHR: 2.12, 95% CI: (1.58 to 2.86)), appropriate-for-gestational-age/large-for-gestational-age and preterm (aHR: 3.23, 95% CI: (2.30 to 4.54)). Neonatal mortality was increased with a history of prior child deaths (aHR: 1.53, 95% CI: (1.24 to 1.87)), being a twin or triplet (aHR: 5.64, 95% CI: (4.25 to 7.48)), births at health posts/clinics or in hospital (aHR: 1.34, 95% CI: (1.13 to 1.58)) and on the way to facilities or outdoors (aHR: 2.26, 95% CI: (1.57 to 3.26)). Risk was lower with increasing maternal height from <145 cm to 145-150 cm (aHR: 0.78, 95% CI: (0.65 to 0.94)) to ≥150 cm (aHR: 0.57, 95% CI: (0.47 to 0.68)), four or more antenatal care (ANC) visits (aHR: 0.67, 95% CI: (0.53 to 0.86)) and education >5 years (aHR: 0.75, 95% CI: (0.62 to 0.92)). CONCLUSION: SGA and/or preterm birth are strongly associated with increased neonatal mortality. To reduce neonatal mortality, interventions that prevent SGA and preterm births by promoting ANC and facility delivery, and care of high-risk infants after birth should be tested. TRIAL REGISTRATION NUMBER: NCT01177111.


Assuntos
Morte Perinatal , Nascimento Prematuro , Recém-Nascido , Gravidez , Criança , Lactente , Feminino , Humanos , Nepal/epidemiologia , Nascimento Prematuro/epidemiologia , Mortalidade Infantil , Fatores de Risco , Estudos de Coortes
20.
Nanoscale ; 15(37): 15405-15414, 2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37702992

RESUMO

To strengthen the electrochemical performance of anode materials for sodium-ion batteries, Cu/Sn co-doped hollow carbon nanofibers functionalized by hybrid CuSn nanospheres (CuSn/C@MCNF) were prepared by a simple electrospinning method. The microstructural characteristics of CuSn/C@MCNF confirmed the same doped elements and strong interactions in hybrid CuSn nanospheres and the hollow carbon nanofiber substrate. CuSn/C@MCNF has superior specific capacity, excellent conductivity and high cycling stability. In particular, the doped hollow carbon nanofiber substrate can facilitate Na+ transport and alleviate volume expansion during the process of sodium storage. When applied as an anode material for sodium-ion batteries, CuSn/C@MCNF can deliver a reversible capacity of 340.1 mA h g-1 at a large current density of 1 A g-1 for 1000 cycles and a high-rate capacity of 202.5 mA h g-1 at 4.0 A g-1, all superior to the corresponding Sn-SnOx@MCNF- and MCNF-based electrodes. This work provides a basic idea for future anode materials in high-performance sodium-ion batteries.

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