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1.
Plant Cell ; 36(6): 2310-2327, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38442314

RESUMO

The dynamic changes in membrane phospholipids affect membrane biophysical properties and cell signaling, thereby influencing numerous biological processes. Nonspecific phospholipase C (NPC) enzymes hydrolyze common phospholipids to release diacylglycerol (DAG), which is converted to phosphatidic acid (PA) and other lipids. In this study, 2 Arabidopsis (Arabidopsis thaliana) tandemly arrayed genes, NPC3 and NPC4, were identified as critical factors modulating auxin-controlled plant growth and tropic responses. Moreover, NPC3 and NPC4 were shown to interact with the auxin efflux transporter PIN-FORMED2 (PIN2). The loss of NPC3 and NPC4 enhanced the endocytosis and vacuolar degradation of PIN2, which disrupted auxin gradients and slowed gravitropic and halotropic responses. Furthermore, auxin-triggered activation of NPC3 and NPC4 is required for the asymmetric PA distribution that controls PIN2 trafficking dynamics and auxin-dependent tropic responses. Collectively, our study reveals an NPC-derived PA signaling pathway in Arabidopsis auxin fluxes that is essential for fine-tuning the balance between root growth and environmental responses.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Fosfolipases Tipo C , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Endocitose , Gravitropismo , Ácidos Indolacéticos/metabolismo , Ácidos Fosfatídicos/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Raízes de Plantas/genética , Plantas Geneticamente Modificadas , Transdução de Sinais , Fosfolipases Tipo C/metabolismo , Fosfolipases Tipo C/genética
2.
Plant Physiol ; 193(3): 1954-1969, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37471275

RESUMO

Ammonium (NH4+) is a key inorganic nitrogen source in cellular amino acid biosynthesis. The coupling of transcriptional and posttranslational regulation of AMMONIUM TRANSPORTER (AMT) ensures that NH4+ acquisition by plant roots is properly balanced, which allows for rapid adaptation to a variety of nitrogen conditions. Here, we report that phospholipase D (PLD)-derived phosphatidic acid (PA) interacts with AMT1;1 to mediate NH4+ uptake in Arabidopsis (Arabidopsis thaliana). We examined pldα1 pldδ-knockout mutants and found that a reduced PA level increased seedling growth under nitrogen deficiency and inhibited root growth upon NH4+ stress, which was consistent with the enhanced accumulation of cellular NH4+. PA directly bound to AMT1;1 and inhibited its transport activity. Mutation of AMT1;1 R487 to Gly (R487G) resulted in abolition of PA suppression and, subsequently, enhancement of ammonium transport activity in vitro and in vivo. Observations of AMT1;1-GFP showed suppressed endocytosis under PLD deficiency or by mutation of the PA-binding site in AMT1;1. Endocytosis was rescued by PA in the pldα1 pldδ mutant but not in the mutant AMT1;1R487G-GFP line. Together, these findings demonstrated PA-based shutoff control of plant NH4+ transport and point to a broader paradigm of lipid-transporter function.


Assuntos
Compostos de Amônio , Proteínas de Arabidopsis , Arabidopsis , Compostos de Amônio/farmacologia , Compostos de Amônio/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Nitrogênio/metabolismo , Ácidos Fosfatídicos/metabolismo , Raízes de Plantas/metabolismo
3.
Psychol Med ; 54(1): 193-202, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37781905

RESUMO

BACKGROUND: Parenting is a common and potent environmental factor influencing adolescent anxiety. Yet, the underlying neurobiological susceptibility signatures remain elusive. Here, we used a longitudinal twin neuroimaging study to investigate the brain network integration and its heritable relation to underpin the neural differential susceptibility of adolescent anxiety to parenting environments. METHODS: 216 twins from the Beijing Twin Study completed the parenting and anxiety assessments and fMRI scanning. We first identified the brain network integration involved in the influences of parenting at age 12 on anxiety symptoms at age 15. We then estimated to what extent heritable sensitive factors are responsible for the susceptibility of brain network integration. RESULTS: Consistent with the differential susceptibility theory, the results showed that hypo-connectivity within the central executive network amplified the impact of maternal hostility on anxiety symptoms. A high anti-correlation between the anterior salience and default mode networks played a similar modulatory role in the susceptibility of adolescent anxiety to paternal hostility. Genetic influences (21.18%) were observed for the connectivity pattern in the central executive network. CONCLUSIONS: Brain network integration served as a promising neurobiological signature of the differential susceptibility to adolescent anxiety. Our findings deepen the understanding of the neural sensitivity in the developing brain and can inform early identification and personalized interventions for adolescents at risk of anxiety disorders.


Assuntos
Ansiedade , Encéfalo , Masculino , Humanos , Adolescente , Criança , Encéfalo/diagnóstico por imagem , Ansiedade/genética , Transtornos de Ansiedade/diagnóstico por imagem , Transtornos de Ansiedade/genética , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Pai , Vias Neurais/diagnóstico por imagem
4.
Brain Topogr ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635017

RESUMO

The post-retrieval extinction paradigm, rooted in reconsolidation theory, holds promise for enhancing extinction learning and addressing anxiety and trauma-related disorders. This study investigates the impact of two reminder types, mild US-reminder (US-R) and CS-reminder (CS-R), along with a no-reminder extinction, on fear recovery prevention in a categorical fear conditioning paradigm. Scalp EEG recordings during reminder and extinction processes were conducted in a three-day design. Results show that the US-R group exhibits a distinctive extinction learning pattern, characterized by a slowed-down yet successful process and pronounced theta-alpha desynchronization (source-located in the prefrontal cortex) during CS processing, followed by enhanced synchronization (source-located in the anterior cingulate) after shock cancellation in extinction trials. These neural dynamics correlate with the subtle advantage of US-R in the Day 3 recovery test, presenting faster spontaneous recovery fading and generally lower fear reinstatement responses. Conversely, the CS reminder elicits CS-specific effects in later episodic tests. The unique neural features of the US-R group suggest a larger prediction error and subsequent effortful conflict learning processes, warranting further exploration.

5.
Environ Health ; 23(1): 45, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702703

RESUMO

BACKGROUND: Volatile organic compounds (VOCs) encompass hundreds of high production volume chemicals and have been reported to be associated with adverse respiratory outcomes such as chronic obstructive pulmonary disease (COPD). However, research on the combined toxic effects of exposure to various VOCs on COPD is lacking. We aimed to assess the effect of VOC metabolite mixture on COPD risk in a large population sample. METHODS: We assessed the effect of VOC metabolite mixture on COPD risk in 5997 adults from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2020 (pre-pandemic) using multivariate logistic regression, Bayesian weighted quantile sum regression (BWQS), quantile-based g-Computation method (Qgcomp), and Bayesian kernel machine regression (BKMR). We explored whether these associations were mediated by white blood cell (WBC) count and total bilirubin. RESULTS: In the logistic regression model, we observed a significantly increased risk of COPD associated with 9 VOC metabolites. Conversely, N-acetyl-S-(benzyl)-L-cysteine (BMA) and N-acetyl-S-(n-propyl)-L-cysteine (BPMA) showed insignificant negative correlations with COPD risk. The overall mixture exposure demonstrated a significant positive relationship with COPD in both the BWQS model (adjusted odds ratio (OR) = 1.30, 95% confidence interval (CI): 1.06, 1.58) and BKMR model, and with marginal significance in the Qgcomp model (adjusted OR = 1.22, 95% CI: 0.98, 1.52). All three models indicated a significant effect of the VOC metabolite mixture on COPD in non-current smokers. WBC count mediated 7.1% of the VOC mixture associated-COPD in non-current smokers. CONCLUSIONS: Our findings provide novel evidence suggesting that VOCs may have adverse associations with COPD in the general population, with N, N- Dimethylformamide and 1,3-Butadiene contributing most. These findings underscore the significance of understanding the potential health risks associated with VOC mixture and emphasize the need for targeted interventions to mitigate the adverse effects on COPD risk.


Assuntos
Inquéritos Nutricionais , Doença Pulmonar Obstrutiva Crônica , Compostos Orgânicos Voláteis , Humanos , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Compostos Orgânicos Voláteis/urina , Masculino , Pessoa de Meia-Idade , Feminino , Estados Unidos/epidemiologia , Adulto , Idoso , Análise de Mediação , Poluentes Atmosféricos/análise , Modelos Logísticos
6.
Geriatr Nurs ; 55: 64-70, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37976557

RESUMO

BACKGROUND: In this prospective study, we evaluated the usefulness of the advanced dementia prognostic tool (ADEPT) for estimating the 2-year survival of persons with advanced dementia (AD) in China. METHODS: The study predicted the 2-year mortality of 115 persons with AD using the ADEPT score. RESULTS: In total, 115 persons with AD were included in the study. Of these persons, 48 died. The mean ADEPT score was 13.0. The AUROC for the prediction of the 2-year mortality rate using the ADEPT score was 0.62. The optimal threshold of the ADEPT score was 11.2, which had an AUROC of 0.63, specificity of 41.8, and sensitivity of 83.3. CONCLUSIONS: The ADEPT score based on a threshold of 11.2 may serve as a prognostic tool to determine the 2-year survival rate of persons with AD in Chongqing, China. However, further studies are needed to explore the nature of this relationship.


Assuntos
Demência , Humanos , Estudos Prospectivos , Prognóstico , China
7.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(4): 450-455, 2024 Apr 10.
Artigo em Zh | MEDLINE | ID: mdl-38565511

RESUMO

OBJECTIVE: To explore the clinical and genetic characteristics of a fetus diagnosed with Congenital myasthenic syndrome type 16 (CMS16). METHODS: A couple who had visited Tianjin Medical University General Hospital in February 2018 due to "adverse outcome of two pregnancies" was selected as the study subject. Clinical data was gathered. Peripheral blood and amniotic fluid samples were collected and subjected to whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing. Low-depth whole-genome sequencing was carried out to detect copy number variation (CNV) in the fetus. RESULTS: The couple's first pregnancy had resulted in a miscarriage at 27+5 weeks, when ultrasound had revealed pleural effusion and polyhydramnios in the fetus. Their second pregnancy was terminated at 30+5 weeks due to fetal hand malformations, polyhydramnios and pleural fluid. Both couple had denied family history of genetic conditions. For their third pregnancy, no CNV abnormality was detected, whilst a compound heterozygous variants, including a maternally derived c.3172C>T (p.R1058W) and paternal c.1431delG (p.K477fs*89) in the SCN4A gene were detected. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.3172C>T (p.R1058W) was predicted as a likely pathogenic variant (PM1+PM2_supporting+PP3+PP4), whilst the c.1431delG (p.K477fs*89) was predicted as a pathogenic variant (PVS1+PM2_supporting+PP4). CONCLUSION: The c.3172C>T (p.R1058W) and c.1431delG (p.K477fs*89) compound heterozygous variants of the SCN4A gene probably underlay the CMS16 in the third fetus.


Assuntos
Aborto Espontâneo , Síndromes Miastênicas Congênitas , Poli-Hidrâmnios , Feminino , Humanos , Gravidez , Variações do Número de Cópias de DNA , Mutação , Síndromes Miastênicas Congênitas/diagnóstico , Síndromes Miastênicas Congênitas/genética , Canal de Sódio Disparado por Voltagem NAV1.4 , Diagnóstico Pré-Natal
8.
BMC Cancer ; 23(1): 824, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667197

RESUMO

BACKGROUND: Wilms' tumour gene 1 (WT1) is clearly recognized as a tumour promoter in diversiform of human malignancies. Nevertheless, knowledge of its expression, functions and potential molecular mechanisms in non-small cell lung cancer (NSCLC) remains elusive. METHODS: Differential expression of WT1 mRNA and protein between NSCLC and normal tissues were assessed by analyzing RNA-seq data from Oncomine and protein data from Human Protein Atlas, respectively. Subsequently, prognosis significance and immune cell infiltration were analyzed by Kaplan-Meier plotter and CIBERSORT. 60 pairs of local NSCLC tissues were involved to validate WT1 expression by quantitative PCR (qPCR) and Western blot. Moreover, Cell Counting Kit-8 (CCK-8), colony formation, transwell, dual luciferase reporter assays and in vivo xenograft tumour growth experiments were conducted to explore the function and mechanism of WT1 in NSCLC. RESULTS: Our solid data indicated that WT1 was increased in NSCLC tissues and cell lines in comparison with their matched controls. In particular, its upregulation correlated with worse prognosis and immune infiltration of the patients. Functional assays demonstrated that knockdown of WT1 inhibited NSCLC malignancy, including inhibiting cell proliferation, survival and invasion. Further exploration discovered that microRNA-498-5p (miR-498-5p) was the upstream suppressor of WT1 by directly targeting the 3' untranslated region (UTR) of WT1 mRNA. Moreover, expression of miR-498-5p was notably decreased and inversely correlated with WT1 in NSCLC tissues. Finally, we proved that miR-498-5p was a potent tumour suppressor in NSCLC by suppressing cell proliferation, survival and invasion, while WT1 restoration could in turn disrupt this suppression both in vitro and in vivo. CONCLUSION: The abnormal increase in WT1 contributes to the malignant properties of NSCLC cells, and miR-498-5p is a natural inhibitor of WT1. Our findings might facilitate the development of novel therapeutic strategies against NSCLC in the future.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Genes do Tumor de Wilms , Neoplasias Pulmonares/genética , Carcinógenos , Regiões 3' não Traduzidas , MicroRNAs/genética , Proteínas WT1/genética
9.
Int J Mol Sci ; 24(2)2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36675032

RESUMO

Dendrobium denneanum is an important medicinal and ornamental plant. Its ornamental and medicinal values are affected by its vegetative growth conditions and chemical composition accumulation. This study adopted an orthogonal experimental design to treat D. denneanum with nine different levels of nitrogen (N), potassium (K), and phosphorus (P). The morphological indicators of the plant were positively correlated with the nitrogen concentration. The polysaccharide content was the highest at 1500 mg·L-1 nitrogen and 3000 mg·L-1 phosphorous and was 26.84% greater than the control. The flavonoid content increased by 36.2% at 500 mg·L-1 nitrogen, 2000 mg·L-1 phosphorous, and 300 mg·L-1 potassium. Principal component score analysis showed that nitrogen had the most significant impact on the various indicators of D. denneanum, followed by phosphorus and potassium. The comprehensive score showed that the T9 treatment (N: 1500 mg·L-1, P: 3000 mg·L-1, K: 500 mg·L-1) had the strongest effect on D. denneanum. Transcriptional analysis showed that compared with the control, the T9 treatment led to 2277 differentially expressed genes (1230 upregulated and 1047 downregulated). This includes fifteen genes enriched in the MAPK signaling pathway, five genes in phenylpropanoid biosynthesis, and two genes in flavonoid biosynthesis. These genes may be involved in regulating plant growth and the biosynthesis of polysaccharides and flavonoids. This study provides guidance for the optimal use of N, P, and K in the cultivation of D. denneanum.


Assuntos
Dendrobium , Dendrobium/genética , Dendrobium/química , Polissacarídeos/química , Flavonoides , Nitrogênio , Fósforo , Potássio , Fertilização
10.
Int J Mol Sci ; 24(19)2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37834139

RESUMO

The growth of Dendrobium nobile is sensitive to heat stress. To find an effective method for enhancing heat tolerance, this study investigated the relieving effect of exogenous calcium at different concentrations (0 mmol/L, 5 mmol/L, 10 mmol/L, 15 mmol/L, 20 mmol/L CaCl2) on heat stress in D. nobile. Principal component analysis was used to screen the optimal exogenous calcium concentration, and transcriptome analysis was used to reveal its possible heat tolerance mechanism. The results showed that compared with the T0, a 10 mmol/L calcium treatment: increased the average leaf length, leaf width, plant height, and fresh matter accumulation of D. nobile by 76%, 103.39%, 12.97%, and 12.24%, respectively (p < 0.05); significantly increased chlorophyll a (Chla), chlorophyll b (Chlb), carotenoids(Car), ascorbic acid (ASA), glutathione (GSH), and flavonoids by 15.72%, 8.54%, 11.88%, 52.17%, 31.54%, and 36.12%, respectively; and effectively enhanced the enzyme activity of the antioxidant system, increasing superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) by 1.38, 1.61, and 2.16 times, respectively (p < 0.05); At the same time, the treatment can effectively reduce the yellow leaf rate and defoliation rate of D. nobile under heat stress. The principal component analysis method and membership function were used to calculate the D value to rank the relief effects of each calcium treatment group, and the results also showed that 10 mmol/L CaCl2 had the best relief effect. Transcriptomics testing identified 7013 differentially expressed genes, of which 2719 were upregulated, and 294 were downregulated. Among them, genes such as HSPA1s, HSP90A, HSPBP1, ATG8, COMT, REF1, E1.11.1.7, along with transcription factors such as MYB, bHLH, WRKY, and NAC, formed the network of tolerance to heat stress in D. nobile. This study provides new insights for improving the cultivation techniques of D. nobile.


Assuntos
Cálcio , Dendrobium , Cálcio/farmacologia , Cloreto de Cálcio/farmacologia , Clorofila A , Transcriptoma , Cálcio da Dieta/farmacologia , Resposta ao Choque Térmico
11.
Molecules ; 28(14)2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37513438

RESUMO

Cowpea (Vigna unguiculata) is one of the main edible legume vegetables in China, and it can improve spleen and stomach function. A polysaccharide component (VUP80-3) has been isolated from V. unguiculata in this study. The average molecular weight of VUP80-3 is 6.43 × 104 Da, and the main monosaccharide group is glucose. The mass ratio of monosaccharide groups in the polysaccharide was glucose:galactose:arabinose:rhamnose:xylose:mannose:fucose = 152.36:24.50:16.53:8.13:1.26:0.97:0.82. NMR analysis showed that VUP80-3 has →4)-α-D-Galp (1→ and →4)-α-D-Glcp(1→ main chain and →3,4)-ß-D-Glcp(1→, →4,6)-α-D-Glcp(1→ branch chains, and the terminal sugar is α-D-Glcp(1→. Biological activity test results showed that VUP80-3 at 1000 µg·mL-1 significantly increased the activity of ethanol injured GES-1 cells (p < 0.01) and significantly reduced reactive oxygen species (ROS) in ethanol injured GES-1 cells and inflammatory factors (IL-8, IL-1ß and TNF-α,) in GES-1 cells. This compound also reduced the apoptosis rate (p < 0.05), thereby significantly reducing the oxidative damage caused by ethanol in GES-1 cells. Therefore, VUP80-3 is a potential drug to protect the gastric mucosa from damage.


Assuntos
Vigna , Polissacarídeos/química , Monossacarídeos/análise , Glucose/química , Etanol
12.
Psychol Med ; 52(4): 675-684, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-32600499

RESUMO

BACKGROUND: The effect of working memory training (WM-T) has been found to transfer to emotional wellbeing, despite some debate on whether an affective component in training is necessary to achieve specific emotion-related benefits. These novel cognitive trainings have not yet been tested in highly anxious individuals, who have deficits in implicit and explicit emotional regulation and should be the potential beneficiaries of these trainings. METHODS: We designed two types of mobile phone-based training applications: (1) WMT and (2) an emotional working memory training (EWM-T) that comprised negative face distraction. Ninety-eight participants (33, WM-T; 35, EWM-T; 30, Control group) with high trait anxiety completed the 21-day intervention or placebo program and conducted pre- and post-test procedures, including questionnaires, emotional regulation and emotional Stroop tasks alongside electroencephalogram recording. Late positive potential (LPP) in emotion regulation task and P3 in the emotional Stroop task were adopted as neutral indicators for the explicit and implicit affective regulation/control processing. RESULTS: Those who had received training (WM-T and EWM-T) showed enhanced explicit regulation (indexed by reduced LPP during reappraisal) compared with the control. Besides, individuals in EWM-T showed reduced behavioral attention bias and a decline of P3 in response to negative faces in an emotional Stroop task. The altered neural indicators were correlated with corresponding behavior indexes that contributed to the anxiety alleviation. CONCLUSIONS: The general WM-T was effective in enhancing explicit emotional regulation, while training with emotional add-in further improved implicit emotional control. (E)WM-T shows potential as a beneficial intervention for the anxiety population.


Assuntos
Regulação Emocional , Ansiedade/terapia , Transtornos de Ansiedade , Emoções/fisiologia , Humanos , Memória de Curto Prazo/fisiologia
13.
Med Sci Monit ; 28: e936898, 2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35891604

RESUMO

BACKGROUND Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer-related death in the world and its poor prognosis is a major concern. Periostin was found to be associated with the prognosis of NSCLC. However, the research results were inconsistent. This meta-analysis evaluated the correlation between periostin expression and the prognosis of NSCLC. MATERIAL AND METHODS A meta-analysis was performed on data acquired from PubMed, EMBASE, the Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang Database from inception to 18 June 2022. Published and unpublished studies investigating the correlation between periostin expression and the prognosis of NSCLC were included in this meta-analysis. Eligible studies reported at least 1 of the following clinical outcome measures: overall survival, progression-free survival, cancer-specific survival, relapse-free survival, disease-free survival, or other clinical parameters of prognosis. Pooled hazard ratios (HR) with 95% confidence interval (CI) were calculated using the random-effects model. Sensitivity and subgroup analyses and assessment of publication bias were also conducted. RESULTS This meta-analysis enrolled 2504 NSCLC cases from 12 eligible studies. The hazard ratio for the overall survival was 1.761 (95% CI: 1.022-3.033, P=0.041). Heterogeneity was significant among the studies, but publication bias was lacking. Subgroup analyses were performed based on different issues, such as districts, antibodies and methods for periostin detection. CONCLUSIONS Overexpression of periostin is a negative prognostic factor and is associated with worse overall survival (OS) in NSCLC patients. Periostin may serve as a prognostic biomarker for NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Intervalo Livre de Doença , Humanos , Recidiva Local de Neoplasia , Prognóstico
14.
J Virol ; 94(14)2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32404523

RESUMO

Anti-human immunodeficiency virus type 1 (anti-HIV-1) fusion peptides have been studied for nearly 2 decades, but few candidates have found useful clinical applications. One factor underlying the failure of such agents to reach the clinic is their poor pharmacokinetic properties, and many efforts have been made to overcome this problem. In this study, we modified C34, a peptide inhibitor of HIV-1 fusion, at its conserved glycosylation site using polyethylene glycols (PEGs) of different molecular weights. PEG40-NC, a conjugate of C34 and branched PEG 40 kDa (PEG40), which has been previously shown to improve the pharmacokinetic profiles of proteins, showed a significantly extended half-life (t1/2; 10.39 h in rats), which compensated for decreased in vitro activity (50% effective concentration [EC50] of 18.51 nM). PEG40-NC also showed a mechanism of action similar to that of C34. PEG40-NC monotherapy in acutely simian-human immunodeficiency virus (SHIV)-infected rhesus monkeys significantly suppressed viral load compared with a control treatment. Efficacy was linked to the extended half-life and lymphatic exposure conferred by attached PEG40. These results highlight the potential of further clinical investigations of PEG40-NC in combination with antiretroviral therapy or other anti-HIV agents.IMPORTANCE Poor pharmacokinetics have severely hindered the clinical use of anti-HIV peptides. Different small molecules, such as lipid, cholesterol, and small PEG, were designed to modify peptides to improve their pharmacokinetics. In this study, we incorporated large branched PEG to anti-HIV peptide and obtained a conjugate with extended half-life and improved in vivo efficacy. The strategy we developed in this study can also be applicable for the development of other peptide candidates.


Assuntos
Proteína gp41 do Envelope de HIV , Inibidores da Fusão de HIV , Infecções por HIV , HIV-1/metabolismo , Fragmentos de Peptídeos , Polietilenoglicóis/química , Síndrome de Imunodeficiência Adquirida dos Símios , Vírus da Imunodeficiência Símia/metabolismo , Animais , Proteína gp41 do Envelope de HIV/química , Proteína gp41 do Envelope de HIV/farmacocinética , Proteína gp41 do Envelope de HIV/farmacologia , Inibidores da Fusão de HIV/química , Inibidores da Fusão de HIV/farmacocinética , Inibidores da Fusão de HIV/farmacologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , Infecções por HIV/patologia , Humanos , Macaca mulatta , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacocinética , Fragmentos de Peptídeos/farmacologia , Síndrome de Imunodeficiência Adquirida dos Símios/tratamento farmacológico , Síndrome de Imunodeficiência Adquirida dos Símios/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/patologia
15.
Neurobiol Learn Mem ; 185: 107531, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34597815

RESUMO

When memories are reactivated, they enter a period of instability in which they can be affected by a variety of follow-up manipulations. The existence of this type of memory reconsolidation offers the potential for clinical interventions of maladaptive memory. However, such potential cannot be fully exploited until the internal mechanisms of memory changes via reconsolidation are better understood. In the current study, we used a three-day AB-AC paradigm that included self-referential simulation processing and employed electroencephalogram (EEG) techniques to explore how post-retrieval updates of episodic memory come about. Behaviorally, we found that reactivation alongside interference learning (ReI-L, AB-AC, n = 52) can produce much more false memories compared to no reactivation new learning (New-L, AB-DC, n = 31) and reactivation repetitive learning (Rep-L, AB-AB. n = 30). More importantly, ERP results revealed that trials from ReI-L in which memory distortions subsequently occurred showed an observable (compared to the new-learning without memory reactivation) but attenuated (compared to trials associating with later intact memory) amplitude of frontal N400, indicating a moderate level of early conflict reactivation is necessary to trigger crucial memory instability. In addition, to promote optimal distortion of the original memory, a sufficient later constructional processing is also required, reflecting in these intrusive/later false trials showed a larger amplitude of late posterior negativity (LPN). A linear classifier employing neuro features of FN400 and LPN during the reconsolidation phase could predict the original memory retention with 72% accuracy. The present findings indicate that nuance in post-retrieval interference, moderate conflict with protracted construction can lead to optimal alterations of episodic memories.


Assuntos
Encéfalo/fisiologia , Consolidação da Memória , Memória Episódica , Adolescente , Adulto , Eletroencefalografia , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino , Consolidação da Memória/fisiologia , Adulto Jovem
16.
Chemistry ; 27(42): 10948-10956, 2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-33998733

RESUMO

Highly selective one-step hydrogenation of phenol to cyclohexanone, an important intermediate in the production of nylon 6 and nylon 66, is desirable but remains a challenge. Pd nanoparticles supported on nitrogen- and oxygen-functionalized carbon nanotubes (NCNTs, OCNTs) were prepared, characterized, and applied in the hydrogenation of phenol to cyclohexanone to study the effect of N-doping. Almost full conversion of phenol with high selectivity to cyclohexanone was achieved over Pd/NCNT under mild reaction conditions using either H2 or formic acid (FA) as a hydrogen source. The effects of reaction temperature and FA/phenol ratio and the reusability were investigated. Separate FA decomposition experiments without and with the addition of phenol were performed to investigate the reaction mechanism, especially the deactivation behavior. Deactivation was observed for both catalysts during the FA decomposition, while only Pd/OCNT rather than Pd/NCNT was deactivated in the transfer hydrogenation with FA and the FA decomposition in the presence of phenol, indicating the unique role of N-doping. Therefore, we assume that deactivation is caused by the strongly bound formates on the active Pd sites, suppressing further FA decomposition and/or transfer hydrogenation on Pd. The nonplanar adsorption of phenol on NCNTs via weak O-H⋅⋅⋅N interactions enables the occurrence of the subsequent hydrogenation by adsorbed formate on Pd.

17.
BMC Cancer ; 21(1): 1218, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34774019

RESUMO

BACKGROUND: MicroRNAs (miRNAs) have been reported to play significant roles in non-small-cell lung cancer (NSCLC). However, the roles of microRNA (miR)-1915-3p in NSCLC remain unclear. In this study, we aimed to explore the biological functions of miR-1915-3p in NSCLC. METHODS: The expression of miR-1915-3p and SET nuclear proto-oncogene (SET) in NSCLC tissues were examined by quantitative real-time PCR (qRT-PCR). Migratory and invasive abilities of lung cancer were tested by wound healing and transwell invasion assay. The direct target genes of miR-1915-3p were measured by dual-luciferase reporter assay and western blot. Finally, the regulation between METTL3/YTHDF2/KLF4 axis and miR-1915-3p were evaluated by qRT-PCR, promoter reporter assay and chromatin immunoprecipitation (CHIP). RESULTS: miR-1915-3p was downregulated in NSCLC tissues and cell lines, and inversely associated with clinical TNM stage and overall survival. Functional assays showed that miR-1915-3p significantly suppressed migration, invasion and epithelial-mesenchymal transition (EMT) in NSCLC cells. Furthermore, miR-1915-3p directly bound to the 3'untranslated region (3'UTR) of SET and modulated the expression of SET. SET inhibition could recapitulate the inhibitory effects on cell migration, invasion and EMT of miR-1915-3p, and restoration of SET expression could abrogate these effects induced by miR-1915-3p through JNK/Jun and NF-κB signaling pathways. What's more, miR-1915-3p expression was regulated by METTL3/YTHDF2 m6A axis through transcription factor KLF4. CONCLUSIONS: These findings demonstrate that miR-1915-3p function as a tumor suppressor by targeting SET and may have an anti-metastatic therapeutic potential for lung cancer treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Proteínas de Ligação a DNA/genética , Expressão Gênica , Chaperonas de Histonas/genética , Neoplasias Pulmonares/genética , MicroRNAs/fisiologia , Células A549 , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Movimento Celular/genética , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , Regulação para Baixo , Transição Epitelial-Mesenquimal/genética , Feminino , Genes Reporter , Genes Supressores de Tumor/fisiologia , Chaperonas de Histonas/antagonistas & inibidores , Chaperonas de Histonas/metabolismo , Humanos , Fator 4 Semelhante a Kruppel/genética , Fator 4 Semelhante a Kruppel/metabolismo , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Metiltransferases/genética , Metiltransferases/metabolismo , MicroRNAs/genética , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
18.
J Environ Manage ; 299: 113584, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34488106

RESUMO

A field test was conducted to study the emission and distribution characteristics of dioxins during co-processing of hazardous waste in a multicomponent slurry gasifier (MCSG). The toxicity equivalent concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in all exhaust gas, waste water, and solid waste under both blank condition (i.e., feedstock was normal coal-water slurry) and test condition (i.e., feedstock mixed with hazardous waste and labeling reagents) were analyzed. Results showed that organic matter was fully degraded in the MCSG. The dioxin amount in the black water flash steam increased with the addition of hazardous waste and chlorine in the feedstock, and octachlorodibenzo-p-dioxins (OCDD) with the largest increase is the most easily formed monomer in dioxins. The dioxin amount in all samples was far below the standard limit in China and other countries. This indicates the low environmental risk from dioxins during the co-processing process. The dioxin distribution trend in solid, liquid, and gas phase during co-processing did not change: 86.63%-94.18%, 0.02%-0.13%, and 5.8%-13.23% of PCDDs were distributed in the exhaust gas, waste water, and solid waste, respectively, while 6.10%-22.95%, 0.59%-0.80%, and 76.45%-93.10% of PCDFs were distributed in the exhaust gas, waste water, and solid waste, respectively.


Assuntos
Dioxinas , Dibenzofuranos Policlorados/análise , Monitoramento Ambiental , Resíduos Perigosos , Incineração , Resíduos Sólidos
19.
J Cell Physiol ; 235(3): 2698-2709, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31512758

RESUMO

Hertwig's epithelial root sheath (HERS) is critical for epithelial-mesenchymal interaction (EMI) during tooth root formation. However, the exact roles of HERS in odontogenic differentiation by EMI have not been well characterized, because primary HERS cells are difficult to obtain. Immortalized cell lines constitute crucial scientific tools, while there are few HERS cell lines available. Our previous study has successfully established immortalized HERS cell lines. Here, we confirmed the phenotype of our HERS-H1 by verifying its characteristics and functions in odontogenic differentiation through EMI. The HERS-H1-conditioned medium (CM-H1) effectively enhanced odontogenic differentiation of dental papilla cells (DPCs) in vitro. Furthermore, Smad4 and p-Smad1/5/8 were significantly activated in DPCs treated with CM-H1, and this activation was attenuated by noggin. In vivo, our implanted recombinants of HERS-H1 and DPCs exhibited mineralized tissue formation and expression of Smad4, p-Smad1/5/8, and odontogenic differentiation markers. Our results indicated that HERS-H1 promoted DPCs odontoblastic differentiation via bone morphogenetic protein/Smad signaling. HERS-H1 exhibits relevant key molecular characteristics and constitutes a new biological model for basic research on HERS and the dental EMI during root development and regeneration.


Assuntos
Papila Dentária/citologia , Transição Epitelial-Mesenquimal/fisiologia , Dente Molar/citologia , Odontogênese/fisiologia , Raiz Dentária/citologia , Animais , Proteínas Morfogenéticas Ósseas/metabolismo , Linhagem Celular , Células Epiteliais/citologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia , Proteína Smad1/metabolismo , Proteína Smad4/metabolismo , Proteína Smad5/metabolismo , Proteína Smad8/metabolismo
20.
Cancer Sci ; 111(1): 239-252, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31729096

RESUMO

Hypoxia-inducible factor 1 (HIF-1) is a critical heterodimeric transcription factor for tumor malignancy. Recently, ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) has been reported to function as a deubiquitinating enzyme for the stabilization of its α subunit (HIF-1α). In the present study, we showed that UCHL1 inhibition can be an effective therapeutic strategy against HIF-1-dependent tumor malignancy. In 2D monolayer culture, a UCHL1 inhibitor suppressed HIF activity and decreased the transcription of HIF downstream genes by inhibiting the UCHL1-mediated accumulation of HIF-1α. Phenotypically, UCHL1 inhibition remarkably blocked cell migration. In 3D spheroid culture models, ectopic expression of UCHL1 significantly upregulated malignancy-related factors such as solidity, volume, as well as viable cell number in an HIF-1α-dependent manner. Conversely, inhibition of the UCHL1-HIF-1 pathway downregulated these malignancy-related factors and also abolished UCHL1-mediated cell proliferation and invasiveness. Finally, inhibition of UCHL1 promoted HIF-1α degradation and lowered the expression of HIF-1 target genes in the 3D model, as also observed in 2D monolayer culture. Our research indicates that the UCHL1-HIF-1 pathway plays a crucial role in tumor malignancy, making it a promising therapeutic target for cancer chemotherapy.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Esferoides Celulares/patologia , Ubiquitina Tiolesterase/genética , Ubiquitinas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo/genética , Regulação da Expressão Gênica/genética , Células HeLa , Humanos , Regulação para Cima/genética
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