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1.
BMC Pregnancy Childbirth ; 24(1): 499, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39054436

RESUMO

BACKGROUND: kangaroo care (KC), endorsed by the World Health Organization, is an evidence-based intervention that plays a pivotal role in mitigating preterm infant mortality and morbidity. However, this intervention has not been fully integrated into healthcare systems in China. This study aimed to gain insight into parents' perceptions and experiences of KC for preterm infants to contribute to the KC implementation on a larger scale. METHODS: This study employed a descriptive qualitative design, using face-to-face, semi-structured, in-depth interviews. Fifteen parents participating in KC for preterm infants in the neonatal intensive care units (NICUs) were purposively sampled from four hospitals across four cities in Zhejiang Province, China. Thematic analysis was employed to analyze the data. RESULTS: Four themes and twelve subthemes regarding the parents' perceptions and experiences about KC were identified. The four themes included: (1) Low motivation upon initial engagement with KC, (2) Dynamic fluctuations of emotional states during KC, (3) Unexpected gains, and (4) Barriers to participation. CONCLUSIONS: Parents' perceptions and experiences of KC was a staged process, with parents exhibiting distinct cognitive patterns and unique experiences at each stage. Overall, as KC progresses, parents' experiences tended to become increasingly positive, despite potential obstacles encountered along the way. To enhance the implementation of KC, healthcare providers could utilize prenatal and postnatal education programs. These programs aim to enhance the understanding of KC among parents of preterm infants, fostering sustained engagement in KC practices.


Assuntos
Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Método Canguru , Pais , Pesquisa Qualitativa , Humanos , Método Canguru/psicologia , China , Recém-Nascido , Feminino , Pais/psicologia , Masculino , Adulto , Percepção , Motivação
2.
Toxicol Appl Pharmacol ; 477: 116697, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37734572

RESUMO

Arsenic exposure is associated with an increased risk of many cancers, and epigenetic mechanisms play a crucial role in arsenic-mediated carcinogenesis. Our previous studies have shown that arsenic exposure induces polyadenylation of H3.1 mRNA and inhibits the deposition of H3.3 at critical gene regulatory elements. However, the precise underling mechanisms are not yet understood. To characterize the factors governing arsenic-induced inhibition of H3.3 assembly through H3.1 mRNA polyadenylation, we utilized mass spectrometry to identify the proteins, especially histone chaperones, with reduced binding affinity to H3.3 under conditions of arsenic exposure and polyadenylated H3.1 mRNA overexpression. Our findings reveal that the interaction between H3.3 and the histone chaperon protein MCM2 is diminished by both polyadenylated H3.1 mRNA overexpression and arsenic treatment in human lung epithelial BEAS-2B cells. The increased binding of MCM2 to H3.1, resulting from elevated H3.1 protein levels, appears to contribute to the reduced availability of MCM2 for H3.3. To further investigate the role of MCM2 in H3.3 deposition during arsenic exposure and H3.1 mRNA polyadenylation, we overexpressed MCM2 in BEAS-2B cells overexpressing polyadenylated H3.1 or exposed to arsenic. Our results demonstrate that MCM2 overexpression attenuates H3.3 depletion at several genomic loci, suggesting its involvement in the arsenic-induced displacement of H3.3 mediated by H3.1 mRNA polyadenylation. These findings suggest that changes in the association between histone chaperone MCM2 and H3.3 due to polyadenylation of H3.1 mRNA may play a pivotal role in arsenic-induced carcinogenesis.


Assuntos
Arsênio , Humanos , Arsênio/toxicidade , Arsênio/química , Chaperonas de Histonas/genética , Carcinogênese , Genômica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Componente 2 do Complexo de Manutenção de Minicromossomo/química , Componente 2 do Complexo de Manutenção de Minicromossomo/metabolismo
3.
J Enzyme Inhib Med Chem ; 38(1): 282-293, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36408835

RESUMO

Receptor-interacting protein kinase 2 (RIPK2) is an essential protein kinase mediating signal transduction by NOD1 and NOD2, which play an important role in regulating immune signalling. In this study, we designed and synthesised a novel series of 4-aminoquinoline-based derivatives as RIPK2 inhibitors. In vitro, compound 14 exhibited high affinity (IC50 = 5.1 ± 1.6 nM) and excellent selectivity to RIPK2 showing in a dendrogram view of the human kinome phylogenetic tree. Bearing favourable lipophilicity and eligible lipophilic ligand efficiency (LipE), compound 14 was selected to investigate cellular anti-inflammatory effect and was identified as a potent inhibitor to reduce the secretion of MDP-induced TNF-α with a dose-dependent manner. Moreover, compound 14 showed moderate stability in human liver microsome. Given these promising results, compound 14 could serve as a favourable inhibitor of RIPK2 for further physiological and biochemical research so as to be used in therapeutic treatment.


Assuntos
Aminoquinolinas , Inflamação , Humanos , Filogenia , Inflamação/tratamento farmacológico , Aminoquinolinas/farmacologia , Transdução de Sinais , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/metabolismo , Proteína Serina-Treonina Quinase 2 de Interação com Receptor/farmacologia
4.
Sensors (Basel) ; 23(11)2023 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-37299794

RESUMO

Disaster monitoring is a primary task for wireless sensor networks. Systems for the rapid reporting of earthquake information are a crucial aspect of disaster monitoring. Furthermore, during emergency rescue after a large earthquake, wireless sensor networks can provide pictures and sound information to save lives. Therefore, when accompanied by multimedia data flow, the alert and seismic data sent by the seismic monitoring nodes must be sufficiently fast. We present herein the architecture of a collaborative disaster-monitoring system that can obtain seismic data in a highly energy-efficient manner. In this paper, a hybrid superior node token ring MAC scheme is proposed for disaster monitoring in wireless sensor networks. This scheme consists of set-up and steady-state stages. A clustering approach was proposed for heterogeneous networks during the set-up stage. The proposed MAC operates in the duty cycle mode at the steady-state stage and is based on the virtual token ring of ordinary nodes, the polling all the superior nodes in one period, and alert transmissions with a low-power listening and shortened preamble approach during the sleep state. The proposed scheme can simultaneously satisfy the requirements of three types of data in disaster-monitoring applications. Based on embedded Markov chains, a model of the proposed MAC was developed and the mean queue length, mean cycle time, and mean upper bound of the frame delay were obtained. Using simulations under various conditions, the clustering approach performed better than the pLEACH approach, and the theoretical results of the proposed MAC were verified. We found that alerts and superior data have outstanding delay and throughput performances even under heavy traffic intensity, and the proposed MAC can provide a data rate of several hundred kb/s for superior and ordinary data. Considering all three types of data, the frame delay performances of the proposed MAC are better than those of the WirelessHART and DRX schemes, and the alert data of the proposed MAC have a maximum frame delay of 15 ms. These satisfy the application requirements of disaster monitoring.


Assuntos
Desastres , Terremotos , Tecnologia sem Fio , Redes de Comunicação de Computadores , Monitorização Fisiológica/métodos
5.
Cancer Control ; 29: 10732748221107590, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35673884

RESUMO

BACKGROUND: With the use of immune-checkpoint inhibitors (ICIs) in advanced or metastatic non-small cell lung cancer (NSCLC), whether ICIs or chemotherapy is more effective still remains controversial. This study was conducted to evaluate the efficacy of programmed cell death 1 (PD-1), programmed cell death ligand 1 (PD-L1), cytotoxic T-lymphocyte protein 4 (CTLA-4) alone or in their combination vs chemotherapy in patients with advanced or metastatic NSCLC. METHODS: This meta-analysis was conducted from PubMed, Web of Science, Medline, Embase, and the Cochrane Library up to March 2021 to identify relevant randomized controlled trials. Primary endpoints were overall survival (OS) and progression-free survival (PFS). Secondary endpoint was adverse events (AEs). This meta-analysis's Prospero registration number is CRD42022323570. RESULTS: The search process has identified 13 studies containing 7918 patients with advanced or metastatic NSCLC. The benefit of PD-1/L1 or CTLA-4 inhibitors alone or in combination compared with chemotherapy for advanced or metastatic NSCLC was elucidated in both OS [HR = .75, 95% CI (.70-.80), P < .001] and PFS [HR = .83, 95% CI (.73-.95), P < .001]. Besides, ICIs were associated with fewer AEs compared to chemotherapy. CONCLUSION: PD-1/L1 or CTLA-4 inhibitors alone or in combination, with fewer AEs, was associated with significant improvements in terms of OS and PFS than chemotherapy in advanced or metastatic NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antígeno B7-H1 , Humanos , Inibidores de Checkpoint Imunológico , Neoplasias Pulmonares/patologia , Receptor de Morte Celular Programada 1/uso terapêutico , Intervalo Livre de Progressão
6.
Acta Pharmacol Sin ; 43(7): 1769-1779, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34819618

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a chronic fatal lung disease characterized by destruction of lung parenchyma and deposition of extracellular matrix in interstitial and alveolar spaces. But known drugs for IPF are far from meeting clinical demands, validation of drug targets against pulmonary fibrosis is in urgent demand. Tyrosine kinase receptor DDRs has been considered as a potential therapeutic target for pulmonary fibrosis due to its pathological collagen binding property and the roles in regulating extracellular matrix remodeling. In this study we designed and synthesized a new indazole derivative XBLJ-13, and identified XBLJ-13 as a highly specific and potent DDRs inhibitor with anti-inflammation and anti-fibrosis activities. We first demonstrated that DDR1/2 was highly expressed in the lung tissues of IPF patients. Then we showed that XBLJ-13 potently inhibited DDR1 and DDR2 kinases with IC50 values of 17.18 nM and 15.13 nM, respectively. Among a panel of 34 kinases tested, XBLJ-13 displayed relatively high selectivity for DDRs with minimal inhibitory effect on PDGFR family and FGFR1, as well as Abl kinase that had high homology with DDRs. Extensive profiling of XBLJ-13 revealed that the new inhibitor had much lower toxicity than nintedanib and better pharmacokinetic properties in mice. Furthermore, pharmacodynamic evaluation conducted in bleomycin-induced pulmonary fibrosis mice showed that administration of XBLJ-13 (30, 60, 90 mg·kg-1·d-1, i.g.) for 12 days significantly and dose-dependently ameliorated lung inflammation and fibrosis. Together, this study confirms that DDRs kinase is a potential target for PF, Particularly, compound XBLJ-13 is a highly potent and specific DDRs inhibitor, along with good pharmacokinetics profiles, and preferable in vivo efficacy, suggesting that it is a potential candidate for the treatment of PF.


Assuntos
Fibrose Pulmonar Idiopática , Animais , Bleomicina/farmacologia , Fibrose , Fibrose Pulmonar Idiopática/tratamento farmacológico , Pulmão/patologia , Camundongos , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Receptores Proteína Tirosina Quinases/metabolismo
7.
BMC Pregnancy Childbirth ; 22(1): 851, 2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36401193

RESUMO

BACKGROUND: Kangaroo mother care (KMC) is an evidence-based intervention that reduces morbidity and mortality in preterm infants. However, it has not yet been fully integrated into health systems around the world. The aim of this study is to provide a cogent summary of the evidence base of the key barriers and facilitators to implementing KMC. METHODS: An umbrella review of existing reviews on KMC was adopted to identify systematic and scoping reviews that analysed data from primary studies. Electronic English databases, including PubMed, Embase, CINAHL and Cochrane Library, and three Chinese databases were searched from inception to 1 July 2022. Studies were included if they performed a review of barriers and facilitators to KMC. Quality assessment of the retrieved reviews was performed by at least two reviewers independently using the Joanna Briggs Institute (JBI) critical appraisal checklist and risk of bias was assessed with the Risk of Bias Assessment Tool for Systematic Reviews (ROBIS) tool. This umbrella review protocol was documented in the PROSPERO registry (CRD42022327994). RESULTS: We generated 531 studies, and after the removal of duplicates and ineligible studies, six eligible reviews were included in the analysis. The five themes identified were environmental factors, professional factors, parent/family factors, access factors, and cultural factors, and the factors under each theme were divided into barriers or facilitators depending on the specific features of a given scenario. CONCLUSIONS: Support from facility management and leadership and well-trained medical staff are of great significance to the successful integration of KMC into daily medical practice, while the parents of preterm infants and other family members should be educated and encouraged in KMC practice. Further research is needed to propose strategies and develop models for implementing KMC.


Assuntos
Método Canguru , Recém-Nascido , Humanos , Criança , Recém-Nascido Prematuro , Revisões Sistemáticas como Assunto , Recém-Nascido de Baixo Peso , Programas Governamentais
8.
Proteomics ; 21(16): e2100035, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34132035

RESUMO

Arsenic pollution impacts health of millions of people in the world. Inorganic arsenic is a carcinogenic agent in skin and lung cancers. The stem-loop binding protein (SLBP) binds to the stem-loop of the canonical histone mRNA and regulates its metabolism during cell cycle. Our previous work has shown arsenic induces ubiquitin-proteasome dependent degradation of SLBP and contributes to lung cancer. In this study, we established the first comprehensive SLBP interaction network by affinity purification-mass spectrometry (AP-MS) analysis, and further demonstrated arsenic enhanced the association between SLBP and a crucial chaperone complex containing heat shock proteins (HSPs) and ERp44. Strikingly, knockdown of these proteins markedly rescued the protein level of SLBP under arsenic exposure conditions, and abolished the increasing migration capacity of BEAS-2B cells induced by arsenic. Taken together, our study provides a potential new mechanism that a chaperone complex containing HSPs and ERp44 attenuates the stability of SLBP under both normal and arsenic exposure conditions, which could be essential for arsenic-induced high cell migration.


Assuntos
Arsênio , Arsênio/toxicidade , Proteínas de Choque Térmico , Humanos , Proteínas de Membrana , Chaperonas Moleculares , Proteínas Nucleares/metabolismo , Ligação Proteica , Estabilidade Proteica , Proteômica , Fatores de Poliadenilação e Clivagem de mRNA
9.
FASEB J ; 34(5): 7178-7191, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32274860

RESUMO

Let-7i modulates the physical function and inflammation in endothelial cells (ECs). However, whether the let-7i of ECs involves in brain vasculature and ischemic stroke is unknown. Using inducible Cadherin5-Cre lineage-tracking mice, a loxp-RNA-sponge conditional knockdown of let-7 in ECs- induced increase of transforming growth factor-ß receptor type 1 (TGF-ßR1), endothelial-mesenchymal transition (endMT), vascular fibrosis, and opening of the brain-blood barrier (BBB). By this lineage-tracking mice, we found that ECs underwent endMT after transient middle cerebral artery occlusion (MCAO). Through specifically overexpressed let-7i in ECs, we found that it reduced TGF-ßR1, endMT, and vascular fibrosis. Furthermore, this overexpression reduced the infarct volume and leakage of the BBB, and improved the neurological function. Further, the expression of let-7i decreased after MCAO, but was reversed by antagonist of TGF-ßR1 or inhibition of Mek phosphorylation. And the inhibition of Mek attenuated the vascular fibrosis after MCAO. In summary, we concluded that ischemic stroke activates a let-7i/TGF-ßR1 double-negative feedback loop, thereby inducing endMT and vascular fibrosis. These results suggest that endMT is a potential target for the treatment of cerebral vascular fibrosis.


Assuntos
Traumatismo Cerebrovascular/patologia , Traumatismo Cerebrovascular/fisiopatologia , MicroRNAs/genética , MicroRNAs/fisiologia , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Receptor do Fator de Crescimento Transformador beta Tipo I/fisiologia , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/fisiopatologia , Animais , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Transdiferenciação Celular , Modelos Animais de Doenças , Endotélio/patologia , Endotélio/fisiopatologia , Retroalimentação Fisiológica , Fibrose , Técnicas de Silenciamento de Genes , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , Masculino , Mesoderma/patologia , Mesoderma/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Ratos , Ratos Sprague-Dawley , Receptor do Fator de Crescimento Transformador beta Tipo I/deficiência
10.
Bioorg Med Chem Lett ; 33: 127749, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33340663

RESUMO

In an in-house screening, 1H-pyrrolo[2,3-b]pyridine scaffold was found to have high inhibition on TNIK. Several series of compounds were designed and synthesized, among which some compounds had potent TNIK inhibition with IC50 values lower than 1 nM. Some compounds showed concentration-dependent characteristics of IL-2 inhibition. These results provided new applications of TNIK inhibitors and new prospects of TNIK as a drug target.


Assuntos
Descoberta de Drogas , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridinas/farmacologia , Pirróis/farmacologia , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/metabolismo , Piridinas/síntese química , Piridinas/química , Pirróis/síntese química , Pirróis/química , Relação Estrutura-Atividade
11.
Invest New Drugs ; 38(3): 700-713, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31267379

RESUMO

The bromodomain and extra-terminal domain (BET) family of proteins, especially bromodomain-containing protein 4 (BRD4), has emerged as exciting anti-tumor targets due to their important roles in epigenetic regulation. Therefore, the discovery of BET inhibitors with promising anti-tumor efficacy will provide a novel approach to epigenetic anticancer therapy. Recently, we discovered the new BET inhibitor compound 171, which is derived from a polo-like kinase 1 (PLK1)-BRD4 dual inhibitor based on our previous research. Compound 171 was found to maintain BET inhibition ability without PLK1 inhibition, and there was no selectivity among BET family members. The in vitro and in vivo results both indicated that the overall anti-tumor activity of compound 171 was improved compared with the (+)-JQ-1 or OTX-015 BET inhibitors. Furthermore, we found that compound 171 could regulate the expression of cell cycle-regulating proteins including c-Myc and p21 and induce cell cycle arrest in the G0/G1 phase. However, compound 171 only has a quite limited effect on apoptosis, in considering that apoptosis was only observed at doses greater than 50 µM. To determine the mechanisms underlying cell death, proliferation activity assay was conducted. The results showed that compound 171 induced clear anti-proliferative effects at doses that no obvious apoptosis was induced, which indicated that the cell cycle arresting effect contributed mostly to its anti-tumor activity. The result of this study revealed the anti-tumor mechanism of compound 171, and laid a foundation for the combination therapy in clinical practice, if compound 171 or its series compounds become drug candidates in the future.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Proteínas/antagonistas & inibidores , Células A549 , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Epigênese Genética/efeitos dos fármacos , Fase G1/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células PC-3 , Fase de Repouso do Ciclo Celular/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Acta Pharmacol Sin ; 41(5): 731-732, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32081977

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

13.
Appl Environ Microbiol ; 85(16)2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31175187

RESUMO

Two new modified Bacillus thuringiensis (Bt) proteins, Cry1Da_7 and Cry1B.868, with activity against fall armyworms (FAW), Spodoptera frugiperda (J.E. Smith), were evaluated for their potential to bind new insect receptors compared to proteins currently deployed as plant-incorporated protectants (PIPs) in row crops. Results from resistant insect bioassays, disabled insecticidal protein (DIP) bioassays, and cell-based assays using insect cells expressing individual receptors demonstrate that receptor utilizations of the newly modified Cry1Da_7 and Cry1B.868 proteins are distinct from each other and from those of commercially available Bt proteins such as Cry1F, Cry1A.105, Cry2Ab, and Vip3A. Accordingly, these two proteins target different insect proteins in FAW midgut cells and when pyramided together should provide durability in the field against this economically important pest.IMPORTANCE There is increased concern with the development of resistance to insecticidal proteins currently expressed in crop plants, especially against high-resistance-risk pests such as fall armyworm (FAW), Spodoptera frugiperda, a maize pest that already has developed resistance to Bacillus thuringiensis (Bt) proteins such as Cry1F. Lepidopteran-specific proteins that bind new insect receptors will be critical in managing current Cry1F-resistant FAW and delaying future resistance development. Results from resistant insect assays, disabled insecticidal protein (DIP) bioassays, and cell-based assays using insect cells expressing individual receptors demonstrate that target receptors of the Cry1Da_7 and Cry1B.868 proteins are different from each other and from those of commercially available Bt proteins such as Cry1F, Cry1A.105, Cry2Ab, and Vip3A. Therefore, pyramiding these two new proteins in maize will provide durable control of this economically important pest in production agriculture.


Assuntos
Proteínas de Bactérias/metabolismo , Endotoxinas/metabolismo , Proteínas Hemolisinas/metabolismo , Proteínas de Insetos/metabolismo , Resistência a Inseticidas , Spodoptera/efeitos dos fármacos , Spodoptera/metabolismo , Animais , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Endotoxinas/genética , Endotoxinas/farmacologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Proteínas de Insetos/genética , Inseticidas/metabolismo , Inseticidas/farmacologia , Doenças das Plantas/parasitologia , Plantas Geneticamente Modificadas/parasitologia , Ligação Proteica , Spodoptera/genética , Zea mays/parasitologia
14.
Chem Res Toxicol ; 32(5): 820-830, 2019 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-30964647

RESUMO

Alzheimer's disease (AD) is the most common form of dementia. The accumulation of ß-amyloid plaques and intracellular neurofibrillary tangles of hyperphosphorylated tau protein are two hallmarks of AD. The ß-amyloid and tau proteins have been at the center of AD research and drug development for decades. However, most of the clinical trials targeting ß-amyloid have failed. Whereas the safety and efficacy of most tau-targeting drugs have not yet been completely assessed, the first tau aggregation inhibitor, LMTX, failed in a late-stage trial, leading to further recognition of the complexities of AD and reconsideration of the amyloid hypothesis and perhaps the tau hypothesis as well. Multilevel complex interactions between genetic, epigenetic, and environmental factors contribute to the occurrence and progression of AD. Formaldehyde (FA) is a widespread environmental organic pollutant. It is also an endogenous metabolite in the human body. Recent studies suggest that elevation of FA in the body by endogenous and/or exogenous exposure may play important roles in AD development. We have demonstrated that FA reduces lysine acetylation of cytosolic histones, thereby compromising chromatin assembly and resulting in the loss of histone content in chromatin, a conserved feature of aging from yeast to humans. Aging is an important factor for AD progression. Therefore, FA-induced inhibition of chromatin assembly and the loss of histones may contribute to AD initiation and/or development. This review will briefly summarize current knowledge on mechanistic insights into AD, focusing on epigenetic alterations and the involvement of FA in AD development. The exploration of chemical exposures as contributing factors to AD may provide new insights into AD mechanisms and could identify potential novel therapeutic targets.


Assuntos
Doença de Alzheimer/etiologia , Epigênese Genética/efeitos dos fármacos , Epigenômica/métodos , Formaldeído/toxicidade , Doença de Alzheimer/genética , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/metabolismo , Animais , Cromatina/genética , Cromatina/metabolismo , DNA/genética , DNA/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Inflamação/fisiopatologia , Estresse Oxidativo/efeitos dos fármacos , Proteínas tau/metabolismo
15.
J Cell Biochem ; 119(10): 8163-8173, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29932233

RESUMO

It has been shown that nuclear expression of S100A4 is significantly correlated with increased metastasis and reduced survival in patients with gastric cancer and many other cancers. However, the factors which could influence the nuclear contents of S100A4 in cancer cells are not clear. It has also been reported that Interleukin-1ß (IL-1ß) promotes the nuclear translocation of S100A4 in chondrocytes. Previous studies have shown that IL-1ß promotes the stemness of colon cancer cells, and S100A4 is also involved in maintaining cancer-initiating cells in head and neck cancers. We speculate that IL-1ß might promote the nuclear translocation of S100A4 protein in MGC803 gastric cancer cells and therefore enhance their stem-like properties. The results from Western-blot and qRT-PCR analysis showed that IL-1ß increased the nuclear and total cellular content of S100A4 protein and S100A4 mRNA level in MGC803 cells. LY294002, a pharmacological inhibitor of Phosphoinositide 3-kinase (PI3K) reversed the above effects. Functional studies indicated that IL-1ß promoted the colony-forming and spheroid-forming capabilities of the cells and the expression of SOX2 and NANOG gene. PI3K or S100A4 inhibition reversed the IL-1ß-mediated increase in colony and spheroid-forming capabilities of the cells. LY294002 also reversed the elevated SOX2 and NANOG expression induced by IL-1ß. Our study demonstrated that IL-1ß promote the nuclear translocation of S100A4 protein in gastric cancer cells MGC803, which are PI3K dependent, suggesting the existence of IL-1ß-PI3K-S100A4 pathway for the first time. The study also showed that IL-1ß promoted stem-like properties of the cells through the new pathway.


Assuntos
Células Epiteliais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Interleucina-1beta/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteína A4 de Ligação a Cálcio da Família S100/metabolismo , Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Cromonas/farmacologia , Citosol/efeitos dos fármacos , Citosol/metabolismo , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patologia , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Morfolinas/farmacologia , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fosfatidilinositol 3-Quinases/genética , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/farmacologia , Proteína A4 de Ligação a Cálcio da Família S100/genética , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo , Transdução de Sinais , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia
16.
J Neurooncol ; 138(2): 383-390, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29476309

RESUMO

To investigate the predictive utility of stimulation threshold (ST) of intraoperative electromyography monitoring for facial nerve (FN) outcomes among vestibular schwannoma (VS) patients postoperatively. The authors enrolled 103 unilateral VS patients who underwent surgical resection into a prospective cohort observational study from January 2013 to April 2015 in our hospital. ST values were used to categorize 81 patients into the "low current" (ST ≤ 0.05 mA) group and 22 patients into the control (ST > 0.05 mA) group. The FN function outcomes were summarized and correlated with these two groups at 1, 3, 6, and 12 months after surgery. Binary regression analysis revealed that the percentage of "good" FN outcome, defined by House-Brackmann (HB) classification of facial function (I-II), in the "low current" group was significantly higher than that of the control group (42.0 vs. 4.5% at 1 month, P = 0.015; 64.2 vs. 31.8% at 3 months, P = 0.024; 72.8 vs. 40.9% at 6 months, P = 0.021; 84.0 vs. 45.5% at 12 months, P = 0.002). Ordinal regression analysis showed that the distribution of HB scores was shifted in a favorable direction in the "low current" group at 1, 3, 6, and 12 months postoperatively. For patients with HB IV at the first month postoperative period, the recovery rate of the "low current" group was significantly higher than that of control group (P = 0.003). "Low current" can predict FN function outcomes better and has faster recovery rates than that of the control group.


Assuntos
Eletromiografia/métodos , Nervo Facial/fisiopatologia , Monitorização Neurofisiológica Intraoperatória/métodos , Neuroma Acústico/fisiopatologia , Neuroma Acústico/cirurgia , Adulto , Idoso , Estimulação Elétrica/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/prevenção & controle , Prognóstico , Estudos Prospectivos , Recuperação de Função Fisiológica , Fatores de Tempo , Adulto Jovem
17.
Bioorg Med Chem ; 25(13): 3315-3329, 2017 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-28462841

RESUMO

Phosphodiesterases are important enzymes regulating signal transduction mediated by second messenger molecules cAMP or cGMP. PDE10A is a unique member in the PDE family because of its selective expression in medium spiny neurons. It is recognized as anti-psychotic drug target. Based on the structural similarity between our previous chemistry work on 8-aminoimidazo[1,2-a]pyrazines and the PDE10A inhibitors reported by Bartolome-Nebreda et al., we initialized a project for developing PDE10A inhibitors. After several rounds of optimization, we were able to obtain a few compounds with good PDE10A enzymatic activity. And after further PDE enzymatic selectivity study, metabolic stability assay and in vivo pharmacological tests we identified two inhibitors as interesting lead compounds with the potential for further PDE10A lead optimizatioin.


Assuntos
Desenho de Fármacos , Diester Fosfórico Hidrolases/metabolismo , Purinas/farmacologia , Animais , Relação Dose-Resposta a Droga , Humanos , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Microssomos/química , Microssomos/metabolismo , Estrutura Molecular , Inibição Pré-Pulso/efeitos dos fármacos , Purinas/síntese química , Purinas/química , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
18.
Arch Biochem Biophys ; 600: 1-11, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27001423

RESUMO

The cotton pests Lygus hesperus and Lygus lineolaris can be controlled by expressing Cry51Aa2.834_16 in cotton. Insecticidal activity of pore-forming proteins is generally associated with damage to the midgut epithelium due to pores, and their biological specificity results from a set of key determinants including proteolytic activation and receptor binding. We conducted mechanistic studies to gain insight into how the first Lygus-active ß-pore forming protein variant functions. Biophysical characterization revealed that the full-length Cry51Aa2.834_16 was a stable dimer in solution, and when exposed to Lygus saliva or to trypsin, the protein underwent proteolytic cleavage at the C-terminus of each of the subunits, resulting in dissociation of the dimer to two separate monomers. The monomer showed tight binding to a specific protein in Lygus brush border membranes, and also formed a membrane-associated oligomeric complex both in vitro and in vivo. Chemically cross-linking the ß-hairpin to the Cry51Aa2.834_16 body rendered the protein inactive, but still competent to compete for binding sites with the native protein in vivo. Our study suggests that disassociation of the Cry51Aa2.834_16 dimer into monomeric units with unoccupied head-region and sterically unhindered ß-hairpin is required for brush border membrane binding, oligomerization, and the subsequent steps leading to insect mortality.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/ultraestrutura , Endotoxinas/química , Proteínas Hemolisinas/química , Proteínas Hemolisinas/ultraestrutura , Heterópteros/química , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Citotóxicas Formadoras de Poros/ultraestrutura , Saliva/química , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/toxicidade , Sítios de Ligação , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Proteínas de Insetos , Proteínas Citotóxicas Formadoras de Poros/toxicidade , Ligação Proteica , Conformação Proteica , Sobrevida , Tripsina/química
19.
Bioorg Med Chem Lett ; 26(18): 4472-4476, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27528435

RESUMO

Menin is an essential oncogenic cofactor for mixed lineage leukemia (MLL)-mediated leukemogenesis, functioning through its direct interaction with MLL1 protein. Therefore, targeting the menin-MLL1 protein-protein interface represents a promising strategy to block MLL-mediated leukemogenesis. On the basis of co-crystal structure analysis, starting from thienopyrimidine chemotype, we have investigated the detailed structure-activity relationship of the piperazinyl-dihydrothiazole moiety. Several compounds were found with potent inhibitory activity against menin and better activities in cell-based experiments than MI-2-2. Molecular docking analysis revealed a less explored subpocket, which could be used for the design of new menin-MLL1 inhibitors.


Assuntos
Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Proteína de Leucina Linfoide-Mieloide/antagonistas & inibidores , Piperidinas/química , Piperidinas/farmacologia , Linhagem Celular Tumoral , Cristalografia por Raios X , Desenho de Fármacos , Histona-Lisina N-Metiltransferase/química , Humanos , Simulação de Acoplamento Molecular , Proteína de Leucina Linfoide-Mieloide/química , Piperidinas/síntese química , Relação Estrutura-Atividade
20.
Acta Pharmacol Sin ; 37(5): 698-707, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27041462

RESUMO

AIM: Aberrant c-Met activation plays a critical role in cancer formation, progression and dissemination, as well as in development of resistance to anticancer drugs. Therefore, c-Met has emerged as an attractive target for cancer therapy. The aim of this study was to develop new c-Met inhibitors and elaborate the structure-activity relationships of identified inhibitors. METHODS: Based on the predicted binding modes of Compounds 5 and 14 in docking studies, a new series of c-Met inhibitor-harboring 3-((1H-pyrrolo[3,2-c]pyridin-1-yl)sulfonyl)imidazo[1,2-a]pyridine scaffolds was discovered. Potent inhibitors were identified through extensive optimizations combined with enzymatic and cellular assays. A promising compound was further investigated in regard to its selectivity, its effects on c-Met signaling, cell proliferation and cell scattering in vitro. RESULTS: The most potent Compound 31 inhibited c-Met kinase activity with an IC50 value of 12.8 nmol/L, which was >78-fold higher than those of a panel of 16 different tyrosine kinases. Compound 31 (8, 40, 200 nmol/L) dose-dependently inhibited the phosphorylation of c-Met and its key downstream Akt and ERK signaling cascades in c-Met aberrant human EBC-1 cancer cells. In 12 human cancer cell lines harboring different background levels of c-Met expression/activation, Compound 31 potently inhibited c-Met-driven cell proliferation. Furthermore, Compound 31 dose-dependently impaired c-Met-mediated cell scattering of MDCK cells. CONCLUSION: This series of c-Met inhibitors is a promising lead for development of novel anticancer drugs.


Assuntos
Antineoplásicos/química , Imidazóis/química , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Piridinas/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Cães , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligação de Hidrogênio , Imidazóis/síntese química , Imidazóis/farmacologia , Células Madin Darby de Rim Canino , Simulação de Acoplamento Molecular , Piridinas/síntese química , Piridinas/farmacologia , Relação Estrutura-Atividade
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