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INTRODUCTION: Evidence strongly suggests that soluble oligomers of amyloid beta protein (oAß) help initiate the pathogenic cascade of Alzheimer's disease (AD). To date, there have been no validated assays specific for detecting and quantifying oAß in human blood. METHODS: We developed an ultrasensitive oAß immunoassay using a novel capture antibody (71A1) with N-terminal antibody 3D6 for detection that specifically quantifies soluble oAß in the human brain, cerebrospinal fluid (CSF), and plasma. RESULTS: Two new antibodies (71A1; 1G5) are oAß-selective, label Aß plaques in non-fixed AD brain sections, and potently neutralize the synaptotoxicity of AD brain-derived oAß. The 71A1/3D6 assay showed excellent dilution linearity in CSF and plasma without matrix effects, good spike recovery, and specific immunodepletion. DISCUSSION: We have created a sensitive, high throughput, and inexpensive method to quantify synaptotoxic oAß in human plasma for analyzing large cohorts of aged and AD subjects to assess the dynamics of this key pathogenic species and response to therapy.
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Doença de Alzheimer , Peptídeos beta-Amiloides , Idoso , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/patologia , Humanos , Imunoensaio , Placa Amiloide/metabolismoRESUMO
Angiogenesis and vasculogenic mimicry (VM) are the main causes of tumor metastasis and recurrence. In this study, we investigated the antiangiogenesis and anti-VM formation of a novel microtubule depolymerizing agent, DHPAC, as well as combretastatin A4 (CA4, a combretastatin derivate) in non-small-cell lung cancer (NSCLC), subsequently elucidating the underlying mechanisms. In human umbilical vein endothelial cells (HUVECs), DHPAC could enter cells and inhibit proliferation, migration, and angiogenesis in the presence and absence of conditioned medium from H1299 cells. Interestingly, the inhibition was enhanced under the stimulation of the conditioned medium. Under hypoxia or normoxia, DHPAC suppressed signal transducer and activator of transcription 3 phosphorylation and reduced vascular endothelial growth factor (VEGF) expression and secretion from HUVECs, thus impeding the activation of the downstream signal transduction pathway of VEGF/VEGFR2. However, JNK inhibitors reversed the inhibitory effect of DHPAC on the angiogenesis, suggesting that DHPAC regulated angiogenesis through activating JNK. In H1299 cells, DHPAC could inhibit proliferation, migration, invasion, and the formation of VM. In addition, DHPAC inhibited the phosphorylation of FAK and AKT and decreased the expressions of VEGF, matrix metalloproteinase 2 (MMP2), MMP9 and Laminin 5, suggesting that DHPAC inhibited VM formation via the FAK/AKT signaling pathway. In addition, CA4 showed a similar effect as DHPAC against angiogenesis and VM formation. These new findings support the use of microtubule destabilizing agents as a promising strategy for cancer therapy.
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OBJECTIVE: Oligomeric forms of amyloid ß protein (oAß) are believed to be principally responsible for neurotoxicity in Alzheimer disease (AD), but it is not known whether anti-Aß antibodies are capable of lowering oAß levels in humans. METHODS: We developed an ultrasensitive immunoassay and used it to measure oAß in cerebrospinal fluid (CSF) from 104 AD subjects participating in the ABBY and BLAZE phase 2 trials of the anti-Aß antibody crenezumab. Patients received subcutaneous (SC) crenezumab (300mg) or placebo every 2 weeks, or intravenous (IV) crenezumab (15mg/kg) or placebo every 4 weeks for 68 weeks. Ninety-eight of the 104 patients had measurable baseline oAß levels, and these were compared to levels at week 69 in placebo (n = 28), SC (n = 35), and IV (n = 35) treated patients. RESULTS: Among those receiving crenezumab, 89% of SC and 86% of IV patients had lower levels of oAß at week 69 versus baseline. The difference in the proportion of patients with decreasing levels was significant for both treatment arms: p = 0.0035 for SC and p = 0.01 for IV crenezumab versus placebo. The median percentage change was -48% in the SC arm and -43% in the IV arm. No systematic change was observed in the placebo group, with a median change of -13% and equivalent portions with negative and positive change. INTERPRETATION: Crenezumab lowered CSF oAß levels in the large majority of treated patients tested. These results support engagement of the principal pathobiological target in AD and identify CSF oAß as a novel pharmacodynamic biomarker for use in trials of anti-Aß agents. ANN NEUROL 2019;86:215-224.
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Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Anticorpos Monoclonais Humanizados/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/líquido cefalorraquidiano , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Iron metabolism plays an important role in insulin resistance, and the triglyceride-glucose (TyG) index has been proposed in recent years as a more accessible and cost-effective marker for insulin resistance. This study aims to evaluate the association between iron metabolism markers, including ferritin (FER), transferrin (TRF), and transferrin receptor (TFR), and the TyG index. A total of 6524 Chinese individuals aged between 18 and 75 years were included in this study. Multivariable linear models were used to investigate the association between FER, TRF, and TFR levels, and the TyG index. Further subgroup analyses stratified by age and sex were also performed. There was a positive association between FER and TRF levels and the TyG index in all 3 multivariable linear regression models, regardless of stratification by sex and age. Additionally, TFR was positively associated with the TyG index among females and those aged ≥45 years, but not among males and those aged <45 years. Our findings reveal a positive association between FER and TRF levels and the TyG index in a Chinese population, while the association between TFR levels and the TyG index showed different patterns depending on age and gender.
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Biomarcadores , Glicemia , Ferritinas , Ferro , Inquéritos Nutricionais , Receptores da Transferrina , Transferrina , Triglicerídeos , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , China , Estudos Transversais , Triglicerídeos/sangue , Receptores da Transferrina/sangue , Ferritinas/sangue , Idoso , Biomarcadores/sangue , Transferrina/análise , Transferrina/metabolismo , Ferro/sangue , Ferro/metabolismo , Adolescente , Glicemia/análise , Glicemia/metabolismo , Adulto Jovem , Resistência à InsulinaRESUMO
The casting mono-like silicon (Si) grown by directional solidification (DS) is promising for high-efficiency solar cells. However, high dislocation clusters around the top region are still the practical drawbacks, which limit its competitiveness to the monocrystalline Si. To optimize the DS-Si process, we applied the framework, which integrates the growing experiments, transient global simulations, artificial neuron network (ANN) training, and genetic algorithms (GAs). First, we grew the Si ingot by the original recipe and reproduced it with transient global modeling. Second, predictions of the Si ingot domain from different recipes were used to train the ANN, which acts as the instant predictor of ingot properties from specific recipes. Finally, the GA equipped with the predictor searched for the optimal recipe according to multi-objective combination, such as the lowest residual stress and dislocation density. We also implemented the optimal recipe in our mono-like DS-Si process for verification and comparison. According to the optimal recipe, we could reduce the dislocation density and smooth the growth rate during the Si ingot growing process. Comparisons of the growth interface and grain boundary evolutions showed the decrease of the interface concavity and the multi-crystallization in the top part of the ingot. The well-trained ANN combined with the GA could derive the optimal growth parameter combinations instantly and quantitatively for the multi-objective processes.
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Importance: Alzheimer disease (AD), a neurodegenerative disease characterized by ß-amyloid plaques and τ tangles in the brain, represents an unmet medical need with no fully approved therapeutics to modify disease progression. Objective: To investigate the safety and efficacy of crenezumab, a humanized monoclonal immunoglobulin G4 antibody targeting ß-amyloid oligomers, in participants with prodromal to mild (early) AD. Design, Setting, and Participants: Two phase 3 multicenter randomized double-blind placebo-controlled parallel-group efficacy and safety studies of crenezumab in participants with early AD, CREAD and CREAD2, were initiated in 2016 and 2017, respectively, and were designed to evaluate the efficacy and safety of crenezumab in participants with early AD. CREAD (194 sites in 30 countries) and CREAD2 (209 sites in 27 countries) were global multicenter studies. A total of 3736 and 3664 participants were screened in CREAD and CREAD2, respectively. A total of 3736 and 3664 participants were screened in CREAD and CREAD2, respectively. Both trials enrolled individuals aged 50 to 85 years with early AD. Participants with some comorbidities and evidence of cerebral infarction or more than 4 microbleeds or areas of leptomeningeal hemosiderosis on magnetic resonance imaging were excluded. After 2923 and 2858 were excluded, respectively, 813 participants in CREAD and 806 in CREAD2 were randomly assigned in a 1:1 ratio to either placebo or crenezumab. In the final analysis, there were 409 participants in the placebo group and 404 in the crenezumab group in CREAD and 399 in the placebo group and 407 in the crenezumab group in CREAD2. Data were analyzed up until January 2019 and August 2019, respectively. Interventions: Participants received placebo or 60 mg/kg crenezumab intravenously every 4 weeks for up to 100 weeks. Main Outcomes and Measures: The primary outcome was change from baseline to week 105 in Clinical Dementia Rating-Sum of Boxes (CDR-SB) score. Results: There were 813 participants in CREAD (mean [SD] age, 70.7 [8.2] years; 483 female and 330 male) and 806 in CREAD2 (mean [SD] age, 70.9 [7.7] years; 456 female and 350 male). Baseline characteristics were balanced between both groups. The between-group difference in mean change from baseline in CDR-SB score (placebo minus crenezumab) was -0.17 (95% CI, -0.86 to 0.53; P = .63) at week 105 in the CREAD study (88 placebo; 86 crenezumab). Compared with previous trials, no new safety signals were identified, and amyloid-related imaging abnormalities with edema were rare, mild, and transient. No meaningful changes in AD biomarkers were observed. Both studies were discontinued following a preplanned interim analysis indicating that CREAD was unlikely to meet the primary end point. Conclusions and Relevance: Crenezumab was well tolerated but did not reduce clinical decline in participants with early AD. Trial Registration: ClinicalTrials.gov Identifiers: CREAD, NCT02670083; CREAD2, NCT03114657.
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Doença de Alzheimer , Anticorpos Monoclonais Humanizados , Adulto , Idoso , Feminino , Humanos , Masculino , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides , Método Duplo-Cego , Placa Amiloide , Resultado do Tratamento , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêuticoRESUMO
Insulin resistance promotes the occurrence of liver cancer and decreases its chemosensitivity. Rosiglitazone (ROSI), a thiazolidinedione insulin sensitiser, could be used for diabetes with insulin resistance and has been reported to show anticancer effects on human malignant cells. In this paper, we investigated the combination of ROSI and chemotherapeutics on the growth and metastasis of insulin-resistant hepatoma. In vitro assay, ROSI significantly enhanced the inhibitory effects of adriamycin (ADR) on the proliferation, autophagy and migration of insulin-resistant hepatoma HepG2/IR cells via downregulation of EGFR/ERK and AKT/mTOR signalling pathway. In addition, ROSI promoted the apoptosis of HepG2/IR cells induced by ADR. In vivo assay, high fat and glucose diet and streptozotocin (STZ) induced insulin resistance in mice by increasing the body weight, fasting blood glucose (FBG) level, oral glucose tolerance, fasting insulin level and insulin resistance index. Both the growth of mouse liver cancer hepatoma H22 cells and serum FBG level in insulin resistant mice were significantly inhibited by combination of ROSI and ADR. Thus, ROSI and ADR in combination showed a stronger anti-tumour effect in insulin resistant hepatoma cells accompanying with glucose reduction and might represent an effective therapeutic strategy for liver cancer accompanied with insulin resistant diabetes.
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Carcinoma Hepatocelular/tratamento farmacológico , Doxorrubicina/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Rosiglitazona/farmacologia , Animais , Animais não Endogâmicos , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Glicemia/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Doxorrubicina/administração & dosagem , Quimioterapia Combinada , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacologia , Resistência à Insulina , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Rosiglitazona/administração & dosagemRESUMO
The availability of blood-based assays detecting Alzheimer's disease (AD) pathology should greatly accelerate AD therapeutic development and improve clinical care. This is especially true for markers that capture the risk of decline in pre-symptomatic stages of AD, as this would allow one to focus interventions on participants maximally at risk and at a stage prior to widespread synapse loss and neurodegeneration. Here we quantify plasma concentrations of an N-terminal fragment of tau (NT1) in a large, well-characterized cohort of clinically normal elderly who were followed longitudinally. Plasma NT1 levels at study entry (when all participants were unimpaired) were highly predictive of future cognitive decline, pathological tau accumulation, neurodegeneration, and transition to a diagnosis of MCI/AD. These predictive effects were particularly strong in participants with even modestly elevated brain ß-amyloid burden at study entry, suggesting plasma NT1 levels capture very early cognitive, pathologic and neurodegenerative changes along the AD trajectory.
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Disfunção Cognitiva/sangue , Disfunção Cognitiva/diagnóstico , Degeneração Neural/sangue , Degeneração Neural/complicações , Proteínas tau/sangue , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/complicações , Peptídeos beta-Amiloides/sangue , Disfunção Cognitiva/complicações , Disfunção Cognitiva/fisiopatologia , Feminino , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória Episódica , Degeneração Neural/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidianoRESUMO
Galectin-3 (Gal-3), the only chimeric lectin of the galectin family, affects numerous biological processes and seems to be involved in different physiological and pathophysiological conditions, such as tumor development, invasion and metastasis as well as immune reactions. There is growing evidence to show that Gal-3 participates in the tumorigenesis, invasion and metastasis as well as tumor immunity in non-small cell lung cancer (NSCLC). A better understanding of the molecular mechanisms of Gal-3 involved in NSCLC development is avidly needed as the basis to identify novel therapeutic targets and develop new strategies for the treatment of NSCLC. In this review, we summarized the distribution and expression of Gal-3 in NSCLC which is highly expressed in NSCLC than in normal lung tissues, and the molecular regulation mechanism of Gal-3 in the development of NSCLC, including upregulation of Wnt/ß-catenin pathway and EGFR expression, involvement in Notch signaling pathway, etc. Moreover, Gal-3 promoted the invasion and metastasis of NSCLC through induction of MMPs secretion, cooperation with integrins, and interaction with mucin 1 to promote cancer-endothelial adhesion. Furthermore, Gal-3 binded to Poly-N-acetyl-lactosamine on N-glycans to promote NSCLC metastasis as well as contributing to tumor microenvironment immunosuppression, which might provide potential therapeutic implications for the clinical treatment of NSCLC.
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Carcinoma Pulmonar de Células não Pequenas/terapia , Galectina 3/metabolismo , Neoplasias Pulmonares/terapia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/metabolismo , Galactanos/química , Galactanos/metabolismo , Galectina 3/química , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Metástase Neoplásica , Prognóstico , Via de Sinalização WntRESUMO
Resistance to chemotherapeutic agents is a major cause of treatment failure in patients with oral cancer. Proton pump inhibitors (PPIs), essentially H+-K+-ATPase inhibitors which are currently used in the treatment of acid related diseases, have demonstrated promising antitumor and chemo-sensitizing efficacy. The main purpose of the present study was to investigate whether pantoprazole (PPZ, one of PPIs) could increase the sensitivity of chemoresistant oral epidermoid carcinoma cells (KB/V) to vincristine (VCR) and elucidate the underlying action mechanism. Results showed that combination treatment of PPZ and VCR synergistically inhibited the proliferation of KB/V cells in vitro and in vivo. Furthermore, administration of PPZ and VCR not only induce apoptosis and G2/M phase arrest in KB/V cells but also suppress the migration and invasion of KB/V cells. The mechanism underlying synergistic anti-tumor effect of PPZ and VCR was related to the inhibition of the function and expression of P-glycoprotein (P-gp) and the down-regulation of EGFR/MAPK and PI3K/Akt/mTOR signaling pathways in KB/V cells. Additionally, we observed that PPZ treatment induced an increase in lysosomal pH and inhibited the activity of lysosomal enzyme acid phosphatase in KB/V cells, which could functionally reduce the sequestration of VCR in lysosomes and sensitized KB/V cells to VCR. In conclusion, our study demonstrated that PPZ could be included in new combined therapy of human oral cancer (especially on VCR-resistant therapy) together with VCR.
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Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Bucais/tratamento farmacológico , Pantoprazol/farmacologia , Vincristina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Células KB , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias Bucais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismoRESUMO
Rosiglitazone (ROSI), a member of thiazolidinediones (TZDs) which act as high-affinity agonists of the nuclear receptor peroxisome-proliferator-activated receptor-γ (PPARγ), is clinically used as an antidiabetic drug which could attenuate the insulin resistance associated with obesity, hypertension, and impaired glucose tolerance in humans. However, recent studies reported that ROSI had significant anticancer effects on various human malignant tumor cells. Mounting evidence indicated that ROSI could exert anticancer effects through PPARγ-dependent or PPARγ-independent ways. In this review, we summarized the PPARγ-dependent antitumor activities of ROSI, which included apoptosis induction, inhibition of cell proliferation and cancer metastasis, reversion of multidrug resistance, reduction of immune suppression, autophagy induction, and antiangiogenesis; and the PPARγ-independent antitumor activities of ROSI, which included inhibition of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway, inhibition of prostaglandin E2 (PGE2), increasing MAPK phosphatase 1 (MKP-1) expression and regulation of other apoptosis-related cell factors. In addition, we discussed the anti-cancer application of ROSI by monotherapy or combination therapy with present chemotherapeutic drugs in vitro and in vivo. Moreover, we reviewed the phase I cancer clinical trials related to ROSI combined with chemotherapeutics and phase II trials about the anti-cancer effects of ROSI monotherapy and the radiotherapy sensitivity of ROSI.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias/tratamento farmacológico , PPAR gama/antagonistas & inibidores , Rosiglitazona/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios Clínicos Fase II como Assunto , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , PPAR gama/metabolismoRESUMO
Soluble Aß oligomers (oAßs) contribute importantly to synaptotoxicity in Alzheimer disease (AD), but the mechanisms related to heterogeneity of synaptic functions at local circuits remain elusive. Nearly all studies of the effects of oAßs on hippocampal synaptic plasticity have only examined homosynaptic plasticity. Here we stimulated the Schaffer collaterals and then simultaneously recorded in stratum radiatum (apical dendrites) and stratum oriens (basal dendrites) of CA1 neurons. We found that the apical dendrites are significantly more vulnerable to oAß-mediated synaptic dysfunction: the heterosynaptic basal dendritic long-term potentiation (LTP) remained unchanged, whereas the homosynaptic apical LTP was impaired. However, the heterosynaptic basal dendritic plasticity induced by either spaced 10-Hz bursts or low-frequency (1-Hz) stimulation was disrupted by oAßs in a mGluR5-dependent manner. These results suggest that different firing patterns in the same neurons may be selectively altered by soluble oAßs in an early phase of AD, before frank neurodegeneration.
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Pathologic, biochemical and genetic evidence indicates that accumulation and aggregation of amyloid ß-proteins (Aß) is a critical factor in the pathogenesis of Alzheimer's disease (AD). Several therapeutic interventions attempting to lower Aß have failed to ameliorate cognitive decline in patients with clinical AD significantly, but most such approaches target only one or two facets of Aß production/clearance/toxicity and do not consider the heterogeneity of human Aß species. As synaptic dysfunction may be among the earliest deficits in AD, we used hippocampal long-term potentiation (LTP) as a sensitive indicator of the early neurotoxic effects of Aß species. Here we confirmed prior findings that soluble Aß oligomers, much more than fibrillar amyloid plaque cores or Aß monomers, disrupt synaptic function. Interestingly, not all (84%) human AD brain extracts are able to inhibit LTP and the degree of LTP impairment by AD brain extracts does not correlate with Aß levels detected by standard ELISAs. Bioactive AD brain extracts also induce neurotoxicity in iPSC-derived human neurons. Shorter forms of Aß (including Aß1-37, Aß1-38, Aß1-39), pre-Aß APP fragments (- 30 to - 1) and N-terminally extended Aßs (- 30 to + 40) each showed much less synaptotoxicity than longer Aßs (Aß1-42 - Aß1-46). We found that antibodies which target the N-terminus, not the C-terminus, efficiently rescued Aß oligomer-impaired LTP and oligomer-facilitated LTD. Our data suggest that preventing soluble Aß oligomer formation and targeting their N-terminal residues with antibodies could be an attractive combined therapeutic approach.