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BACKGROUND: Duchenne muscular dystrophy (DMD) is a progressive and devastating muscle disease, resulting from the absence of dystrophin. This leads to cell membrane instability, susceptibility to contraction-induced muscle damage, subsequent muscle degeneration, and eventually disability and early death of patients. Currently, there is no cure for DMD. Our recent studies identified that lipin1 plays a critical role in maintaining myofiber stability and integrity. However, lipin1 gene expression levels are dramatically reduced in the skeletal muscles of DMD patients and mdx mice. METHODS: To identify whether increased lipin1 expression could prevent dystrophic pathology, we employed unique muscle-specific mdx:lipin1 transgenic (mdx:lipin1Tg/0) mice in which lipin1 was restored in the dystrophic muscle of mdx mice, intramuscular gene delivery, as well as cell culture system. RESULTS: We found that increased lipin1 expression suppressed muscle degeneration and inflammation, reduced fibrosis, strengthened membrane integrity, and resulted in improved muscle contractile and lengthening force, and muscle performance in mdx:lipin1Tg/0 compared to mdx mice. To confirm the role of lipin1 in dystrophic muscle, we then administered AAV1-lipin1 via intramuscular injection in mdx mice. Consistently, lipin1 restoration inhibited myofiber necroptosis and lessened muscle degeneration. Using a cell culture system, we further found that differentiated primary mdx myoblasts had elevated expression levels of necroptotic markers and medium creatine kinase (CK), which could be a result of sarcolemmal damage. Most importantly, increased lipin1 expression levels in differentiated myoblasts from mdx:lipin1Tg/0 mice substantially inhibited the elevation of necroptotic markers and medium CK levels. CONCLUSIONS: Overall, our data suggest that lipin1 is a promising therapeutic target for the treatment of dystrophic muscles.
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Camundongos Endogâmicos mdx , Músculo Esquelético , Distrofia Muscular de Duchenne , Fosfatidato Fosfatase , Animais , Distrofia Muscular de Duchenne/patologia , Distrofia Muscular de Duchenne/metabolismo , Fosfatidato Fosfatase/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Camundongos Transgênicos , Camundongos , Contração Muscular , Terapia de Alvo Molecular , Camundongos Endogâmicos C57BL , Terapia Genética , MasculinoRESUMO
Duchenne muscular dystrophy (DMD) is a severe muscle wasting disorder caused by dystrophin mutations, leading to the loss of sarcolemmal integrity, and resulting in progressive myofibre necrosis and impaired muscle function. Our previous studies suggest that lipin1 is important for skeletal muscle regeneration and myofibre integrity. Additionally, we discovered that mRNA expression levels of lipin1 were significantly reduced in skeletal muscle of DMD patients and the mdx mouse model. To understand the role of lipin1 in dystrophic muscle, we generated dystrophin/lipin1 double knockout (DKO) mice, and compared the limb muscle pathology and function of wild-type B10, muscle-specific lipin1 deficient (lipin1Myf5cKO ), mdx and DKO mice. We found that further knockout of lipin1 in dystrophic muscle exhibited a more severe phenotype characterized by increased necroptosis, fibrosis and exacerbated membrane damage in DKO compared to mdx mice. In barium chloride-induced muscle injury, both lipin1Myf5cKO and DKO showed prolonged regeneration at day 14 post-injection, suggesting that lipin1 is critical for muscle regeneration. In situ contractile function assays showed that lipin1 deficiency in dystrophic muscle led to reduced specific force production. Using a cell culture system, we found that lipin1 deficiency led to elevated expression levels of necroptotic markers and medium creatine kinase, which could be a result of sarcolemmal damage. Most importantly, restoration of lipin1 inhibited the elevation of necroptotic markers in differentiated primary lipin1-deficient myoblasts. Overall, our data suggests that lipin1 plays complementary roles in myofibre stability and muscle function in dystrophic muscles, and overexpression of lipin1 may serve as a potential therapeutic strategy for dystrophic muscles. KEY POINTS: We identified that lipin1 mRNA expression levels are significantly reduced in skeletal muscles of Duchenne muscular dystrophy patients and mdx mice. We found that further depletion of lipin1 in skeletal muscles of mdx mice induces more severe dystrophic phenotypes, including enhanced myofibre sarcolemma damage, muscle necroptosis, inflammation, fibrosis and reduced specific force production. Lipin1 deficiency leads to elevated expression levels of necroptotic markers, whereas restoration of lipin1 inhibits their expression. Our results suggest that lipin1 is functionally complementary to dystrophin in muscle membrane integrity and muscle regeneration.
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Distrofina , Distrofia Muscular de Duchenne , Animais , Camundongos , Modelos Animais de Doenças , Distrofina/metabolismo , Fibrose , Camundongos Endogâmicos mdx , Músculo Esquelético/fisiologia , Regeneração , RNA Mensageiro/metabolismoRESUMO
Photodetectors and imagers based on 2D layered materials are currently subject to a rapidly expanding application space, with an increasing demand for cost-effective and lightweight devices. However, the underlying carrier transport across the 2D homo- or heterojunction channel driven by the external electric field, like a gate or drain bias, is still unclear. Here, a visible-near infrared photodetector based on van der Waals stacked molybdenum telluride (MoTe2 ) and black phosphorus (BP) is reported. The type-I and type-II band alignment can be tuned by the gate and drain voltage combined showing a dynamic modulation of the conduction polarity and negative differential transconductance. The heterojunction devices show a good photoresponse to light illumination ranging from 520-2000 nm. The built-in potential at the MoTe2 /BP interface can efficiently separate photoexcited electron-hole pairs with a high responsivity of 290 mA W-1 , an external quantum efficiency of 70%, and a fast photoresponse of 78 µs under zero bias.
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The neurotoxicity of 2,2',4,4'-tetrabromodiphenyl ether (PBDE-47) is closely linked to mitochondrial abnormalities while mitophagy is vital for mitochondrial homeostasis. However, whether PBDE-47 disrupts mitophagy contributing to impaired neurodevelopment remain elusive. Here, this study showed that neonatal PBDE-47 exposure caused learning and memory deficits in adult rats, accompanied with striatal mitochondrial abnormalities, neuronal apoptosis and the resultant neuronal loss. Mechanistically, PBDE-47 suppressed PINK1/Parkin-mediated mitophagy induction and degradation, inducing mitophagosome accumulation and mitochondrial dysfunction in vivo and in vitro. Additionally, stimulation of mitophagy by adenovirus-mediated Parkin or Autophagy-related protein 7 (Atg7) overexpression aggravated PBDE-47-induced mitophagosome accumulation, mitochondrial dysfunction, neuronal apoptosis and death. Conversely, suppression of mitophagy by the siRNA knockdown of Atg7 rescued PBDE-47-induced detrimental consequences. Importantly, melatonin, a hormone secreted rhythmically by the pineal, improved PBDE-47-caused neurotoxicity via preventing neuronal apoptosis and loss by restoring mitophagic activity and mitochondrial function. These neuroprotective effects of melatonin depended on activation of the AMP-activated protein kinase (AMPK)/Unc-51-like kinase 1 (ULK1) signaling. Collectively, these data indicate that PBDE-47 impairs mitophagy to perturb mitochondrial homeostasis, thus triggering apoptosis, leading to neuronal loss and consequent neurobehavioral deficits. Manipulation of the AMPK-mitophagy axis via melatonin could be a novel therapeutic strategy against developmental PBDE-47 neurotoxicity.
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Melatonina , Síndromes Neurotóxicas , Ratos , Animais , Mitofagia , Proteínas Quinases Ativadas por AMP/metabolismo , Melatonina/farmacologia , Ubiquitina-Proteína Ligases/metabolismoRESUMO
The G allele of rs4702 polymorphism has been reported to reduce the production of mature BDNF and FURIN, both of which were closely associated with cognitive functions. Real-time PCR, ELISA and luciferase assay were performed to explore the interactions between miR-338-3p, FURIN and BDNF. T-RFLP was used to assess the intestinal flora in the stool samples of glioma patients after radiotherapy. We grouped the 106 glioma patients recruited according to the rs4702 polymorphism. The results showed no obvious correlation between rs4702 polymorphism and the expression of miR-338-3p. However, rs4702-A was associated with increased expression of FURIN and BDNF in the serum and PBMC of glioma patients after radiotherapy. Besides, the study found that rs4702-A was remarkably associated with increased enterotype I and decreased enterotype III in the stool of glioma patients after radiotherapy. Rs4702-A was also proved to be closely associated with increased MMSE, role functioning and social functioning at three months after radiotherapy. Furthermore, miR-338-3p repressed the expression of FURIN-G. Compared with G allele, the presence of A allele of rs4702 polymorphism in FURIN could obstruct the suppressive effect of miR-338-3p upon the expression of FURIN and BDNF in intestinal flora. Therefore, the carriers of A allele will be challenged with less risk of radiotherapy-induced cognitive impairment.
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Disfunção Cognitiva , Glioma , MicroRNAs , Regiões 3' não Traduzidas/genética , Disfunção Cognitiva/genética , Furina/genética , Glioma/genética , Glioma/metabolismo , Glioma/radioterapia , Humanos , Leucócitos Mononucleares/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismoRESUMO
LncRNA-PTENP1 was reported to promote multiple myeloma cancer stem cell proliferation, and the G allele of rs7853346 polymorphism in lncRNA-PTENP1 was demonstrated to enhance the effect of lncRNA-PTENP1. In this study, we aimed to study the potential effect of lncRNA-PTENP1 and CCR2 mRNA polymorphisms on cognitive impairment in glioma patients. In this study, 279 glioma patients were recruited and grouped according to their genotypes of rs7853346 in PTENP1 and rs1799864 in CCR1. Pathogenic parameters were collected from patients before radiotherapy (month 0) or at month 1 and month 3 after radiotherapy to study the effect of rs7853346 and rs1799864 on cognitive impairment. Sequence analysis, luciferase assay, real-time PCR, and Western blot were performed to study the regulatory relationships between lncRNA-PTENP1, miR-18b, and CCR2. The glioma patient groups exhibited no significant differences concerning basic characteristics. However, the CG&GG/GG genotype alleviated radiotherapy-induced cognitive impairment by exhibiting the highest MMSE among the four groups. On the contrary, parameters including the severity of depression, bladder control, global health status, itchy skin, and weakness of legs all showed no difference among different patient groups at month 0, month 1, and month 3. Also, a long-term positive effect of CG&GG/GG genotype on role functioning and social functioning was also observed after radiotherapy. Compared with patients carrying the CC genotype of rs7853346, the expression of lncRNA-PTENP1 was reduced while the miR-19b level was elevated in patients carrying the CG&GG genotypes of rs7853346. Moreover, the expression of CCR2 mRNA was the highest in the CC/GA&AA group and the lowest in the CG&GG/GG group. Subsequent sequence analysis and luciferase assay indicated that miR-19b could bind to lncRNA-PTENP1 and 3'UTR of CCR2 mRNA, and the knockdown of lncRNA-PTENP1 led to evident up-regulation of miR-19b and down-regulation of CCR2 mRNA/protein in a cellular model, thus verifying the presence of the lncRNA-PTENP1/miR-19b/CCR2 mRNA signaling pathway. In conclusion, by studying the changes in the key parameters of glioma patients who were subjected to radiotherapy, we concluded that the rs7853346 polymorphism in lncRNA-PTENP1 and the rs1799864 polymorphism in CCR2 could independently affect cognitive impairment, while a more significant combined effect on cognitive impairment was exerted in glioma patients via the signaling pathway of PTENP1/miR-19b/CCR2.
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Disfunção Cognitiva , Glioma , MicroRNAs , RNA Longo não Codificante , Regiões 3' não Traduzidas , Disfunção Cognitiva/genética , Glioma/genética , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genética , Receptores CCR2/genética , Transdução de Sinais/genéticaRESUMO
Disruption of cholinergic neurotransmission can affect cognition, but little is known about whether low-to-moderate fluoride exposure affects cholinergic system and its effect on the prevalence of dental fluorosis (DF) and intelligence quotient (IQ). A cross-sectional study was conducted to explore the associations of moderate fluoride exposure and cholinergic system in relation to children's DF and IQ. We recruited 709 resident children in Tianjin, China. Ion selective electrode method was used to detect fluoride concentrations in water and urine. Cholinergic system was assessed by the detection of choline acetyltransferase (ChAT), acetylcholinesterase (AChE) and acetylcholine (ACh) levels in serum. Compared with children in the first quartile, those in fourth quartile the risk of either developing DF or IQ < 120 increased by 19% and 20% for water and urinary fluoride. The risk of having both increased by 58% and 62% in third and fourth quartile for water fluoride, 52% and 65% for urinary fluoride. Water fluoride concentrations were positively associated with AChE and negatively associated with ChAT and ACh, trends were same for urinary fluoride except for ACh. The risk of either developing DF or having non-high intelligence rose by 22% (95%CI: 1.07%, 1.38%) for the fourth quartile than those in the first quartile of AChE, for having the both, the risk was 1.27 (95%CI: 1.07, 1.50), 1.37 (95%CI: 1.17, 1.62) and 1.44 (95%CI: 1.23, 1.68) in second, third and fourth quartiles. The mediation proportion by AChE between water fluoride and either developing DF or IQ < 120 was 15.7%. For both to exist, the proportion was 6.7% and 7.2% for water and urinary fluoride. Our findings suggest low-to-moderate fluoride exposure was associated with dysfunction of cholinergic system for children. AChE may partly mediate the prevalence of DF and lower probability of having superior and above intelligence.
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A set of coordinated interactions between gut microbiota and the immune cells surveilling the intestine play a key role in shaping local immune responses and intestinal health. Gpr109a is a G protein-coupled receptor expressed at a very high level on innate immune cells and previously shown to play a key role in the induction of colonic regulatory T cells. In this study, we show that Gpr109a-/-Rag1-/- mice exhibit spontaneous rectal prolapse and colonic inflammation, characterized by the presence of an elevated number of IL-17-producing Rorγt+ innate lymphoid cells (ILCs; ILC3). Genetic deletion of Rorγt alleviated the spontaneous colonic inflammation in Gpr109a-/-Rag1-/- mice. Gpr109a-deficient colonic dendritic cells produce higher amounts of IL-23 and thereby promote ILC3. Moreover, the depletion of gut microbiota by antibiotics treatment decreased IL-23 production, ILC3, and colonic inflammation in Gpr109a-/-Rag1-/- mice. The ceca of Gpr109a-/-Rag1-/- mice showed significantly increased colonization by members of Bacteroidaceae, Porphyromonadaceae, Prevotellaceae, Streptococcaceae, Christensenellaceae, and Mogibacteriaceae, as well as IBD-associated microbiota such as Enterobacteriaceae and Mycoplasmataceae, compared with Rag1-/- mice, housed in a facility positive for Helicobacter and murine norovirus. Niacin, a Gpr109a agonist, suppressed both IL-23 production by colonic DCs and ILC3 number in a Gpr109a-dependent manner. Collectively, our data present a model suggesting that targeting Gpr109a will be potentially beneficial in the suppression of IL-23-mediated immunopathologies.
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Colite/imunologia , Colite/microbiologia , Microbioma Gastrointestinal/imunologia , Interleucina-23/biossíntese , Linfócitos/imunologia , Receptores Acoplados a Proteínas G/imunologia , Animais , Colo/citologia , Colo/imunologia , Imunidade nas Mucosas/imunologia , Mediadores da Inflamação , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos KnockoutRESUMO
BACKGROUND: This study aimed to explore the correlation of A-kinase-interacting protein 1 (AKIP1) expression with clinical characteristics as well as survival profiles in non-small-cell lung cancer (NSCLC) patients, and further investigate its underlying effect on regulating NSCLC cell functions. METHODS: 319 NSCLC patients who underwent resection were consecutively reviewed, and AKIP1 expression (in 319 tumor tissues and 145 adjacent tissues) was determined by immunohistochemistry. Disease-free survival (DFS) and overall survival (OS) were calculated. In vitro, control overexpression, AKIP1 overexpression, control shRNA and AKIP1 shRNA plasmids were transfected into A549 cells to evaluate the effect of AKIP1 on cell proliferation and apoptosis. RESULTS: A-kinase-interacting protein 1 expression was increased in tumor tissues compared to adjacent tissues, and it positively correlated with tumor size, lymph node metastasis and TNM stage in NSCLC patients. Kaplan-Meier curves displayed that AKIP1 high expression correlated with worse DFS and OS, and multivariate Cox's regression revealed that it was an independent predictive factor for poor survival profiles. In vitro experiments displayed that AKIP1 expression was elevated in PC9 and A549 cells compared to normal lung epithelial cells; moreover, cell proliferation was increased by AKIP1 upregulation but reduced by AKIP1 downregulation, and cell apoptosis was decreased by AKIP1 upregulation but increased by AKIP downregulation in A549 cells. Interestingly, AKIP1 promoted fibronectin and zinc finger E-box binding homeobox 1 expressions while reduced E-cadherin expression in A549 cells. CONCLUSION: A-kinase-interacting protein 1 overexpression correlates with deteriorative tumor features and worse survival profiles and promotes cell proliferation but represses apoptosis in NSCLC.
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Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Proteínas Nucleares/metabolismo , Células A549 , Proteínas Adaptadoras de Transdução de Sinal/genética , Idoso , Apoptose/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/cirurgia , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genéticaRESUMO
Esophageal cancer ranks the eighth most common cancer and the sixth most common cause of cancer death worldwide. MicroRNAs (miRNAs) are small noncoding RNAs that regulate a wide variety of cancer-related cellular processes. In the current study, a series of previously published gene expression microarray data from Gene Expression Ominus and The Cancer Genome Atlas were downloaded and further divided into training, internal, and external validation sets. Least absolute shrinkage and selectionator operator Cox regression model along with 10-fold cross-validation was performed to select the miRNAs associated with the prognosis of esophageal squamous cell carcinoma (ESCC) and constructed a six-miRNA signature. Then the prediction accuracy of this signature was assessed in validation and test set using Kaplan-Meier analysis, time-dependent receiver operating characteristic (ROC) curves and dynamic area under the ROC curve. According to the result, the prediction accuracy of miRNA signature was much better than that of tumor-node-metastasis (TNM) stage in all the three sets. Stratified analysis also demonstrated that the predict ability of this signature was independent of TNM stage. Finally, function experiments including apoptosis and colony formation assay were performed to further reveal the regulatory role of miRNAs in ESCC. Our study demonstrated the promising potential application of this novel six-miRNA signature as an independent biomarker for survival prediction of ESCC patients.
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Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , MicroRNAs/genética , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Feminino , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias/métodos , Prognóstico , Curva ROCRESUMO
Emerging evidence has indicated that microRNAs (miRNAs) play an important role in cervical cancer (CC). However, the role of miRNA (miR)-665 in cervical cancer remains unclear. The aim of the present study was to investigate the potential functions of miR-665 in CC and to identify the underlying mechanisms of action. Herein, we show that miR-665 was downregulated in CC tissues and cell lines, which is negatively correlated with tumor size, distant metastasis, advanced TNM stage and poor prognosis. Functionally, miR-665 inhibited cell proliferation, migration and invasion and resistance of cisplatin for CC cells, as well as tumor growth. We validated that transforming growth factor beta receptor 1 (TGFBR1) was a direct target of miR-665 and mediated the ERK/SMAD pathway. In addition, we identified miR-665 as the competing endogenous RNA for long noncoding (lnc)-DANCR. These observations suggested that lnc-DANCR-mediated miR-665 downregulation regulates the malignant phenotype of CC cells by targeting TGFBR1 through the ERK/SMAD pathway, which may present a pathway for novel therapeutic stratagems for CC therapy.
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Proliferação de Células/genética , Sistema de Sinalização das MAP Quinases/genética , MicroRNAs/genética , Metástase Neoplásica/genética , RNA Longo não Codificante/genética , Proteínas Smad/genética , Neoplasias do Colo do Útero/genética , Animais , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica/patologia , Prognóstico , Receptor do Fator de Crescimento Transformador beta Tipo I/genética , Neoplasias do Colo do Útero/patologiaRESUMO
As one of the most frequently diagnosed cancers, esophageal squamous cell carcinoma (ESCC) remains the leading cause of malignancy-related death worldwide. Many studies have focused on the potential role of cancer cells in educating B cells during cancer progression. Here, we aim to explore the role of circulating exosomes from ESCC in the generation of two main regulatory B (Breg) subsets, including interleukin-10+ Bregs (B10) and programmed cell death (PD)-1high Bregs. Firstly, we observed an elevated percentage of B10 cells in peripheral blood of ESCC patients compared with healthy controls. Then we isolated and characterized exosomes from the peripheral blood of ESCC patients and an ESCC cell line. Exosomes from ESCC patients and the ESCC cell line suppressed the proliferation of B cells and induced the augmentation of B10 and PD-1high Breg cells. By comparing the long non-coding RNA and mRNA expression profiles in exosomes from ESCC patients or healthy controls, we identified a series of differentially expressed genes. Finally, we undertook gene annotation and pathway enrichment analyses on differentially expressed genes to explore the potential mechanism underlying the modulatory role of cancer exosomes in B cells. Our findings contribute to the study on B cell-mediated ESCC immunosuppression and shed light on the possible application of exosomes in anticancer therapies.
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Linfócitos B Reguladores/imunologia , Neoplasias Esofágicas/imunologia , Carcinoma de Células Escamosas do Esôfago/imunologia , Exossomos/imunologia , Linfócitos B Reguladores/metabolismo , Diferenciação Celular/imunologia , Terapia Baseada em Transplante de Células e Tecidos/métodos , Neoplasias Esofágicas/sangue , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/sangue , Carcinoma de Células Escamosas do Esôfago/terapia , Exossomos/transplante , Feminino , Humanos , Interleucina-10/metabolismo , Masculino , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/metabolismoRESUMO
Autophagy and apoptosis are two important cellular processes that are crucial for neurodevelopment. Evidence shows that apoptosis is implicated in fluoride neurotoxicity. However, the biological roles of autophagy, especially its interplay with apoptosis in the neurotoxicity induced by long-term fluoride exposure remain unclear. Here we present in vivo and in vitro evidence that fluoride-induced defective autophagy elicits excessive apoptosis, thus inducing neurotoxicity. Using Sprague-Dawley rats exposed to sodium fluoride from 60â¯days before pregnancy until 6â¯months post-delivery as in vivo model, we showed that fluoride impaired the learning and memory abilities of offspring rats, with decreased neuronal number, suppressed autophagy and enhanced apoptosis in hippocampus. These results were validated in human neuroblastoma SH-SY5Y cells in vitro. Mechanistically, mTOR signaling, responsible for autophagy induction, was activated in vivo and in vitro, and targeting inhibition of mTOR with rapamycin protected SH-SY5Y cells from defective autophagy and excessive apoptosis, thereby enhancing neuronal survival. Furthermore, circulating levels of autophagy markers were low in children with higher fluoride body burden and lower intelligence quotient scores. Collectively, our results suggest that defective autophagy plays a pivotal role in fluoride neurotoxicity, and mTOR might be a promising target for the prevention and treatment of fluoride neurotoxicity.
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Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Cognição/efeitos dos fármacos , Fluoretos/efeitos adversos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Criança , Feminino , Humanos , Masculino , Memória/efeitos dos fármacos , Neuroblastoma/metabolismo , Neurônios/efeitos dos fármacos , Síndromes Neurotóxicas/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismoRESUMO
Spiral configurations and helical curlings of plant tendrils and seed pods are very common in nature. Many researchers have tried to develop spirally deformable actuators to mimic these natural spirals through several approaches, such as preforming helical shapes, processing diagonal stripes and employing anisotropic organic layers. However, these methods are usually complex and time-consuming. Here, we used an efficient method to produce a highly oriented carbon nanotube (CNT) film and develop a series of spirally deformable soft actuators which perform various controllable helical actuations. The actuator consists of a CNT layer with strong anisotropy and a silicone layer. By simply adjusting the orientations of the aligned CNTs, the prepared actuators can accomplish left- or right-handed spiral deformations with different helical forms when driven by electricity. Finite element analyses and simulations were conducted to investigate the mechanism. It is confirmed that it is the anisotropic moduli of the CNT film that regulate the internal stress distributions of the actuators and lead to helical actuations. Moreover, complex actuator designs and functional applications were also carried out. A V-shaped actuator can simultaneously achieve left- and right-handed curling with large angles (630°), which vividly imitates the spiral winding of a tendril. A Y-shaped actuator performed three-dimensional movements, which can manipulate lightweight objects deftly. By virtue of easy preparation and flexible function design, the spirally deformable actuators based on the oriented CNT film will be very promising in artificial muscles and bionic soft robots.
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Nanotubos de Carbono , Anisotropia , Biônica , Dimetilpolisiloxanos , RobóticaRESUMO
Increasingly targeted in drug discovery, protein-protein interactions challenge current high throughput screening technologies in the pharmaceutical industry. Developing an effective and efficient method for screening small molecules or compounds is critical to accelerate the discovery of ligands for enzymes, receptors and other pharmaceutical targets. Here, we report developments of methods to increase the signal-to-noise ratio (SNR) for screening protein-protein interactions using atomic force microscopy (AFM) force spectroscopy. We have demonstrated the effectiveness of these developments on detecting the binding process between focal adhesion kinases (FAK) with protein kinase B (Akt1), which is a target for potential cancer drugs. These developments include optimized probe and substrate functionalization processes and redesigned probe-substrate contact regimes. Furthermore, a statistical-based data processing method was developed to enhance the contrast of the experimental data. Collectively, these results demonstrate the potential of the AFM force spectroscopy in automating drug screening with high throughput.
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Fluoride neurotoxicity is associated with mitochondrial disruption. Mitochondrial fission/fusion dynamics is crucial to maintain functional mitochondria, yet little is known about how fluoride perturbs this dynamics and whether such perturbation contributes to impaired neurodevelopment. Here in human neuroblastoma SH-SY5Y cells treated with sodium fluoride (NaF, 20, 40 and 60 mg/L), mitochondrial fission suppression exerted a central role in NaF-induced mitochondrial abnormalities and the resulting autophagy deficiency, apoptosis augmentation, and compromised neuronal survival. Mechanically, pharmacological inhibition of mitochondrial fission exacerbated NaF-induced mitochondrial defects and cell death through promoting apoptosis despite partial autophagy restoration. Conversely, genetic enhancement of mitochondrial fission alleviated NaF-produced detrimental mitochondrial and cellular outcomes by elevating autophagy and inhibiting apoptosis. Further suppressing autophagy was harmful, while blocking apoptosis was beneficial for cellular survival in this context. Consistently, using Sprague-Dawley rats developmentally exposed to NaF (10, 50, and 100 mg/L) from pre-pregnancy until 2 months of delivery to mimic human exposure, we showed that perinatal exposure to environmentally relevant levels of fluoride caused learning and memory impairments, accompanied by hippocampal mitochondrial morphological alterations manifested as fission suppression and fusion acceleration, along with defective autophagy, excessive apoptosis and neuronal loss. Intriguingly, the disturbed circulating levels of identified mitochondrial fission/fusion molecules were closely associated with intellectual loss in children under long-term environmental drinking water fluoride exposure. Collectively, our results suggest that mitochondrial fission inhibition induces mitochondrial abnormalities, triggering abnormal autophagy and apoptosis, thus contributing to neuronal death, and that the mitochondrial dynamics molecules may act as promising indicators for developmental fluoride neurotoxicity.
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Poluentes Ambientais/toxicidade , Sistema Nervoso/efeitos dos fármacos , Fluoreto de Sódio/toxicidade , Animais , Apoptose , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia , Sobrevivência Celular , Criança , Cognição , Feminino , Fluoretos , Humanos , Masculino , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/efeitos dos fármacos , Síndromes Neurotóxicas , Gravidez , Ratos , Ratos Sprague-Dawley , Testes de ToxicidadeRESUMO
High fluoride exposure has been related to harmful health effects, but the impacts of low-to-moderate fluoride on child growth and obesity-related outcomes remain unclear. We performed a large-scale cross-sectional study to examine the association between low-to-moderate fluoride in drinking water and anthropometric measures among Chinese school-age children. We recruited 2430 resident children 7-13â¯years of age, randomly from low-to-moderate fluorosis areas of Baodi District in Tianjin, China. We analyzed the fluoride contents in drinking water and urine samples using the national standardized ion selective electrode method. Multivariable linear and logistic analyses were used to assess the relationships between fluoride exposure and age- and sex-standardized height, weight and body mass index (BMI) z-scores, and childhood overweight/obesity (BMI z-scoreâ¯>â¯1). In adjusted models, each log unit (roughly 10-fold) increase in urinary fluoride concentration was associated with a 0.136 unit increase in weight z-score (95% CI: 0.039, 0.233), a 0.186 unit increase in BMI z-score (95% CI: 0.058, 0.314), and a 1.304-fold increased odds of overweight/obesity (95% CI: 1.062, 1.602). These associations were stronger in girls than in boys (Pinteractionâ¯=â¯0.016), and children of fathers with lower education levels were more vulnerable to fluoride (Pinteractionâ¯=â¯0.056). Each log unit (roughly 10-fold) increase in water fluoride concentration was associated with a 0.129 unit increase in height z-score (95% CI: 0.005, 0.254), but not with other anthropometric measures. Our results suggest low-to-moderate fluoride exposure is associated with overweight and obesity in children. Gender and paternal education level may modify the relationship.
Assuntos
Exposição Ambiental/análise , Fluoretos/análise , Fluorose Dentária/epidemiologia , Obesidade Infantil/epidemiologia , Adolescente , Índice de Massa Corporal , Peso Corporal/efeitos dos fármacos , Criança , China/epidemiologia , Estudos Transversais , Água Potável/química , Exposição Ambiental/efeitos adversos , Feminino , Fluoretos/urina , Humanos , Masculino , Sobrepeso/epidemiologia , Distribuição AleatóriaRESUMO
Infrared imaging systems have wide range of military or civil applications and 2D nanomaterials have recently emerged as potential sensing materials that may outperform conventional ones such as HgCdTe, InGaAs, and InSb. As an example, 2D black phosphorus (BP) thin film has a thickness-dependent direct bandgap with low shot noise and noncryogenic operation for visible to mid-infrared photodetection. In this paper, the use of a single-pixel photodetector made with few-layer BP thin film for near-infrared imaging applications is demonstrated. The imaging is achieved by combining the photodetector with a digital micromirror device to encode and subsequently reconstruct the image based on compressive sensing algorithm. Stationary images of a near-infrared laser spot (λ = 830 nm) with up to 64 × 64 pixels are captured using this single-pixel BP camera with 2000 times of measurements, which is only half of the total number of pixels. The imaging platform demonstrated in this work circumvents the grand challenges of scalable BP material growth for photodetector array fabrication and shows the efficacy of utilizing the outstanding performance of BP photodetector for future high-speed infrared camera applications.
RESUMO
Black phosphorus (BP), owing to its distinguished properties, has become one of the most competitive candidates for photodetectors. However, there has been little attention paid on photo-response performance of multilayer BP nanoflakes with large layer thickness. In fact, multilayer BP nanoflakes with large layer thickness have greater potential from the fabrication viewpoint as well as due to the physical properties than single or few layer ones. In this report, the thickness-dependence of the intrinsic property of BP photodetectors in the dark was initially investigated. Then the photo-response performance (including responsivity, photo-gain, photo-switching time, noise equivalent power, and specific detectivity) of BP photodetectors with relative thicker thickness was explored under a near-infrared laser beam (λIR = 830 nm). Our experimental results reveal the impact of BP's thickness on the current intensity of the channel and show degenerated p-type BP is beneficial for larger current intensity. More importantly, the photo-response of our thicker BP photodetectors exhibited a larger responsivity up to 2.42 A/W than the few-layer ones and a fast response photo-switching speed (response time is ~2.5 ms) comparable to thinner BP nanoflakes was obtained, indicating BP nanoflakes with larger layer thickness are also promising for application for ultra-fast and ultra-high near-infrared photodetectors.
RESUMO
This network meta-analysis (NMA) was conducted to compare the predictive value of 14 SNPs in eight DNA repair genes on the efficacy of platinum-based chemotherapy in patients with non-small cell lung cancer (NSCLC). These included ERCC1 (rs11615, rs3212986, rs3212948), XRCC1 (rs25487, rs25489, rs1799782), XPD (rs13181, rs1799793), XPG (rs1047768, rs17655), XPA (rs1800975), XRCC3 (rs861539), APE1 (rs3136820), and RRM1 (rs1042858). The PubMed and Cochrane library databases were reviewed from their inception to February 2017 and studies which met our inclusion criteria were included in our investigation. This network meta-analysis combines direct and indirect evidence to assess the predictive value of 14 SNPs in eight DNA repair genes on the efficacy of platinum-based chemotherapy in NSCLC. We evaluated the predictive value through the use of the odd ratios (OR) and drawing surface under the cumulative ranking curves (SUCRA). A total of 26 eligible cohort studies were enrolled in this NMA. The pairwise meta-analysis indicated that in terms of overall response ratio (ORR), ERCC1 (rs11615), XRCC1 (rs25487, rs1799782), and XPD (rs13181) polymorphisms are associated with the efficacy of platinum-based chemotherapy in NSCLC. The result of this NMA suggests that there is no significant difference in predictive value of 8 DNA repair genes on the efficacy of platinum-based chemotherapy in NSCLC patients. The rank of SUCRA values of the 14 SNPs in the eight DNA repair genes were: XPD (rs1799793)âERCC1 (rs3212986)âXPA(rs1800975)âERCC1(rs3212948)âXRCC1(rs25487)âXRCC3(rs861539)âAPE1(rs3136820)âERCC1(rs11615)âXRCC1(rs1799782)âRRM1(rs1042858)âXPD(rs13181)âXPG (rs1047768)âXPG(rs17655)âXRCC1(rs25489). ERCC1(rs11615), XRCC1(rs25487, rs1799782) and XPD(rs13181) polymorphisms were better predictors in evaluating the efficacy of platinum-based chemotherapy in NSCLC patients. J. Cell. Biochem. 118: 4782-4791, 2017. © 2017 Wiley Periodicals, Inc.