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1.
EMBO J ; 41(7): e109187, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35191554

RESUMO

Hypoxia regulates tumor angiogenesis, metabolism, and therapeutic response in malignant cancers including glioblastoma, the most lethal primary brain tumor. The regulation of HIF transcriptional factors by the ubiquitin-proteasome system is critical in the hypoxia response, but hypoxia-inducible deubiquitinases that counteract the ubiquitination remain poorly defined. While the activation of ERK1/2 also plays an important role in hypoxia response, the relationship between ERK1/2 activation and HIF regulation remains elusive. Here, we identified USP33 as essential deubiquitinase that stabilizes HIF-2alpha protein in an ERK1/2-dependent manner to promote hypoxia response in cancer cells. USP33 is preferentially induced in glioma stem cells by hypoxia and interacts with HIF-2alpha, leading to its stabilization through deubiquitination. The activation of ERK1/2 upon hypoxia promoted HIF-2alpha phosphorylation, enhancing its interaction with USP33. Silencing of USP33 disrupted glioma stem cells maintenance, reduced tumor vascularization, and inhibited glioblastoma growth. Our findings highlight USP33 as an essential regulator of hypoxia response in cancer stem cells, indicating a novel potential therapeutic target for brain tumor treatment.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Neoplasias Encefálicas , Glioma , Células-Tronco Neoplásicas , Ubiquitina Tiolesterase , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Neoplasias Encefálicas/patologia , Hipóxia Celular , Glioma/patologia , Humanos , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo
2.
J Nanobiotechnology ; 21(1): 261, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553718

RESUMO

The development of natural membranes as coatings for nanoparticles to traverse the blood-brain barrier (BBB) presents an effective approach for treating central nervous system (CNS) disorders. In this study, we have designed a nanogel loaded with PACAP and estrogen (E2), sheathed with exosomes and responsive to reactive oxygen species (ROS), denoted as HA NGs@exosomes. The objective of this novel design is to serve as a potent drug carrier for the targeted treatment of perimenopausal depression. The efficient cellular uptake and BBB penetration of HA NGs@exosomes has been demonstrated in vitro and in vivo. Following intranasal intervention with HA NGs@exosomes, ovariectomized mice under chronic unpredictable mild stress (CUMS) have shown improved behavioral performance, indicating that HA NGs@exosomes produced a rapid-onset antidepressant effect. Moreover, HA NGs@exosomes exhibit notable antioxidant and anti-inflammatory properties and may regulate the expression of pivotal proteins in the PACAP/PAC1 pathway to promote synaptic plasticity. Our results serve as a proof-of-concept for the utility of exosome-sheathed ROS-responsive nanogel as a promising drug carrier for the treatment of perimenopausal depression.


Assuntos
Depressão , Exossomos , Camundongos , Animais , Nanogéis , Depressão/tratamento farmacológico , Depressão/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Exossomos/metabolismo , Perimenopausa/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Portadores de Fármacos/metabolismo
3.
Oncologist ; 26(8): 660-667, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33728733

RESUMO

BACKGROUND: Randomized controlled trials (RCTs) are the gold standard for evidence-based practice, but their development and implementation is resource intensive. We aimed to describe modern RCTs in gastrointestinal (GI) cancer and identify predictors of successful accrual and publication. MATERIALS AND METHODS: ClinicalTrials.gov was queried for phase III GI cancer RCTs opened between 2010 and 2019 and divided into two cohorts: past and recruiting. Past trials were analyzed for predictors of successful accrual and the subset with ≥3 years follow-up were analyzed for predictors of publication. Univariate and multivariable (MVA) logistic regression were used to identify covariates associated with complete accrual and publication status. RESULTS: A total of 533 GI RCTs were opened from 2010 to 2019, 244 of which are still recruiting. In the "past" trials cohort (235/533) MVA, Asian continent of enrollment was a predictor for successful accrual, whereas trials with prolonged enrollment (duration longer than median of 960 days) trended to failed accrual. Predictors for publication on MVA included international enrollment and accrual completion. Sponsorship was not associated with accrual or publication. Notably, 33% of past trials remain unpublished, and 60% of trials that were closed early remain unpublished. CONCLUSION: Accrual rate and the primary continent of enrollment drive both trial completion and publication in GI oncology. Accrual must be streamlined to enhance the impact of RCTs on clinical management. A large portion of trials remain unpublished, underscoring the need to encourage dissemination of all trials to, at a minimum, inform future trial design. IMPLICATIONS FOR PRACTICE: Two-thirds of gastrointestinal (GI) oncology phase III randomized controlled trials successfully accrue; however, one third of these trials are unpublished and more than half of trials that close early are unpublished. The strongest predictors for publication are successful accrual and international collaborations. Initiatives to optimize the trial enrollment process need to be explored to maximize the potential for trials to engender progress in clinical practice. Moreover, this study identified a significant publication bias in the realm of GI oncology, and the field should promote reporting of all trials in order to better inform future trial questions and design.


Assuntos
Oncologia , Neoplasias , Viés de Publicação , Ensaios Clínicos Fase III como Assunto , Humanos , Modelos Logísticos , Ensaios Clínicos Controlados Aleatórios como Assunto
4.
Pharmacol Res ; 169: 105658, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33992797

RESUMO

Pancreatic cancer is one of the most aggressive cancers with a poor prognosis and 5-year low survival rate. In the present study, we report that bruceine A, a quassinoid found in Brucea javanica (L.) Merr. has a strong antitumor activity against human pancreatic cancer cells both in vitro and in vivo. Human proteome microarray reveals that 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 4 (PFKFB4) is the candidate target of bruceine A and both fluorescence measurement and microscale thermophoresis suggest bruceine A binds to PFKFB4. Bruceine A suppresses glycolysis by inhibiting PFKFB4, leading to cell cycle arrest and apoptosis in MIA PaCa-2 cells. Furthermore, glycogen synthase kinase-3 ß (GSK3ß) is identified as a downstream target of PFKFB4 and an PFKFB4-interacting protein. Moreover, bruceine A induces cell growth inhibition and apoptosis through GSK3ß, which is dysregulated in pancreatic cancer and closely related to the prognosis. In all, these findings suggest that bruceine A inhibits human pancreatic cancer cell growth via PFKFB4/GSK3ß-mediated glycolysis, and it may serve as a potent agent for curing human pancreatic cancer.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/metabolismo , Neoplasias Pancreáticas/tratamento farmacológico , Fosfofrutoquinase-2/metabolismo , Quassinas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos Endogâmicos BALB C , Camundongos Nus , Microscopia de Fluorescência , Transplante de Neoplasias , Neoplasias Pancreáticas/metabolismo , Reação em Cadeia da Polimerase , Quassinas/farmacologia
5.
J Biomech Eng ; 143(8)2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33817746

RESUMO

Diffuse alveolar damage (DAD) is a characteristic histopathologic pattern in most cases of acute respiratory distress syndrome and severe viral pneumonia, such as COVID-19. DAD is characterized by an acute phase with edema, hyaline membranes, and inflammation followed by an organizing phase with pulmonary fibrosis and hyperplasia. The degree of pulmonary fibrosis and surface tension is different in the pathological stages of DAD. The effects of pulmonary fibrosis and surface tension on alveolar sac mechanics in DAD are investigated by using the fluid-structure interaction (FSI) method. The human pulmonary alveolus is idealized by a three-dimensional honeycomb-like geometry, with alveolar geometries approximated as closely packed 14-sided polygons. A dynamic compression-relaxation model for surface tension effects is adopted. Compared to a healthy model, DAD models are created by increasing the tissue thickness and decreasing the concentration of the surfactant. The FSI results show that pulmonary fibrosis is more influential than the surface tension on flow rate, volume, P-V loop, and resistance. The lungs of the disease models become stiffer than those of the healthy models. According to the P-V loop results, the surface tension plays a more important role in hysteresis than the material nonlinearity of the lung tissue. Our study demonstrates the differences in air flow and lung function on the alveolar sacs between the healthy and DAD models.


Assuntos
Fenômenos Mecânicos , Modelos Biológicos , Alvéolos Pulmonares/patologia , Fibrose Pulmonar/patologia , Fenômenos Biomecânicos , Difusão , Humanos , Tensão Superficial
6.
J Cell Mol Med ; 24(6): 3359-3369, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31990147

RESUMO

The purpose of the present study was to evaluate the anti-cancer property of Lobetyolin on colorectal cancer and explore its potential mechanism. Lobetyolin was incubated with HCT-116 cells in the absence or presence of ASCT2 inhibitor Benser or p53 inhibitor Pifithrin-α. The levels of glutamine, glutamic acid, α-ketoglutarate, ATP and GSH were determined to measure the glutamine metabolism. Annexin V-FITC/PI staining and TUNEL assay were applied to estimate the apoptotic condition. The levels of ASCT2 were examined by RT-qPCR, Western blot and immunofluorescence staining. The expressions of cleaved-caspase-3, caspase-3, cleaved-caspase-7, caspase-7, cleaved-PARP, PARP, p53, p21, bax and survivin were detected using Western blot analysis. As a result, the treatment with Lobetyolin effectively induced apoptosis and glutamine metabolism in HCT-116 cells through ASCT2 signalling. The inhibition of ASCT2 reduced the glutamine-related biomarkers and augmented the apoptotic process. We further found that the effect of Lobetyolin on HCT-116 was related to the expressions of p21 and bax, and transportation of p53 to nucleus. The inhibition of p53 by Pifithrin-α promoted the inhibitory effect of Lobetyolin on ASCT2-mediated apoptosis. Lobetyolin also exerted anti-cancer property in nude mice. In conclusion, the present work suggested that Lobetyolin could induce the apoptosis via the inhibition of ASCT2-mediated glutamine metabolism, which was possibly governed by p53.


Assuntos
Sistema ASC de Transporte de Aminoácidos/antagonistas & inibidores , Antineoplásicos/farmacologia , Apoptose/fisiologia , Neoplasias do Colo/tratamento farmacológico , Glutamina/metabolismo , Poli-Inos/farmacologia , Proteína Supressora de Tumor p53/antagonistas & inibidores , Animais , Benzotiazóis/farmacologia , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Células HCT116 , Humanos , Camundongos , Camundongos Nus , Antígenos de Histocompatibilidade Menor , Tolueno/análogos & derivados , Tolueno/farmacologia
7.
Am J Public Health ; 110(12): 1837-1843, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33058712

RESUMO

Objectives. To compare the epidemic prevention ability of COVID-19 of each province in China and to evaluate the existing prevention and control capacity of each province.Methods. We established a quasi-Poisson linear mixed-effects model using the case data in cities outside Wuhan in Hubei Province, China. We adapted this model to estimate the number of potential cases in Wuhan and obtained epidemiological parameters. We estimated the initial number of cases in each province by using passenger flowrate data and constructed the extended susceptible-exposed-infectious-recovered model to predict the future disease transmission trends.Results. The estimated potential cases in Wuhan were about 3 times the reported cases. The basic reproductive number was 3.30 during the initial outbreak. Provinces with more estimated imported cases than reported cases were those in the surrounding provinces of Hubei, including Henan and Shaanxi. The regions where the number of reported cases was closer to the predicted value were most the developed areas, including Beijing and Shanghai.Conclusions. The number of confirmed cases in Wuhan was underestimated in the initial period of the outbreak. Provincial surveillance and emergency response capabilities vary across the country.


Assuntos
COVID-19/epidemiologia , COVID-19/prevenção & controle , China/epidemiologia , Humanos , Pandemias , SARS-CoV-2 , Índice de Gravidade de Doença , Meios de Transporte/estatística & dados numéricos , Viagem/estatística & dados numéricos
8.
Epilepsy Behav ; 102: 106589, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31726317

RESUMO

Brainstem raphe (BR) hypoechogenicity in transcranial sonography (TCS) has been depicted in patients with depression. But, up to date, the association of BR alterations in TCS with depression in patients with epilepsy has never been reported. This study was to investigate the possible role of BR examination via TCS in patients with idiopathic generalized epilepsy with tonic-clonic seizures (IGE-TCS) and depression. Forty-six patients with IGE-TCS and 45 healthy controls were recruited. Echogenicity of the caudate nuclei (CN), lentiform nuclei (LN), substantia nigra (SN), and BR and widths of the lateral ventricle (LV) frontal horns and the third ventricle (TV) were assessed via TCS. The determination of depression was based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV), and depression severity measured by Chinese version Neurological Disorders Depression Inventory for Epilepsy (C-NDDI-E) and Beck Depression Inventory-II (BDI-II). The width of TV in patients with epilepsy was found significantly larger than that in healthy controls (p = 0.001), but there was no significant difference in TV width between patients with IGE-TCS with and without depression. There were no significant differences between patients with IGE-TCS and healthy controls in LV frontal horn width, as well as in SN, CN, LN, and BR echogenicity. Here, it seems that patients with IGE-TCS were detected with smaller SN echogenic area compared with controls though they had no statistical significance. Patients with IGE-TCS with hypoechogenic BR had significantly higher C-NDDI-E and BDI-II scores than those with normal BR signal, and most patients with IGE-TCS with depression exhibited hypoechogenic BR, but few patients with IGE-TCS without depression exhibited hypoechogenic BR. In conclusion, BR echogenic signal alterations in TCS can be a biomarker for depression in epilepsy, but it might not be associated with epilepsy itself. The alterations of SN echogenic area and TV width in TCS may reflect a potential role of SN and diencephalon structure in the pathogenesis of epilepsy, which needs to be further elucidated.


Assuntos
Tronco Encefálico/diagnóstico por imagem , Depressão/diagnóstico por imagem , Epilepsia Generalizada/diagnóstico por imagem , Convulsões/diagnóstico por imagem , Ultrassonografia Doppler Transcraniana/métodos , Adulto , Depressão/epidemiologia , Depressão/psicologia , Epilepsia Generalizada/epidemiologia , Epilepsia Generalizada/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Convulsões/epidemiologia , Convulsões/psicologia , Adulto Jovem
9.
Clin Exp Pharmacol Physiol ; 47(7): 1311-1319, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32124474

RESUMO

Cancer stem cells have been identified as the major cause of cancer initiation and progression. To investigate the effects of puerarin 6″-O-xyloside (PXY), derived from Pueraria lobata (Willd.) Ohwi, on lung cancer stem cells, we enriched and identified a subpopulation of lung cancer stem-like cells (LCSLCs) derived from lung adenocarcinoma A549 cells with traits including high self-renewal and invasive capability in vitro, elevated tumourigenicity in vivo, and high expression of stem cell markers CD44, CD133 and aldehyde dehydrogenase 1 (ALDH1). We found that PXY could impair cell viability, suppress self-renewal and invasive capability, and decrease CD133, CD44 and ALDH1 mRNA expression in LCSLCs in a dose-dependent manner. Furthermore, we showed that PXY suppressed the self-renewal and invasive capability of LCSLCs at least in part through suppressing the activation of Akt/c-Myc signalling. In conclusion, PXY can block the traits of LCSLCs, indicating that PXY may be a candidate compound for lung adenocarcinoma therapy via eliminating LCSLCs.


Assuntos
Autorrenovação Celular/efeitos dos fármacos , Isoflavonas/farmacologia , Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células A549 , Humanos , Isoflavonas/química , Invasividade Neoplásica , Células-Tronco Neoplásicas/patologia
10.
PLoS Genet ; 13(1): e1006535, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28072828

RESUMO

Folliculogenesis is a progressive and highly regulated process, which is essential to provide ova for later reproductive life, requires the bidirectional communication between the oocyte and granulosa cells. This physical connection-mediated communication conveys not only the signals from the oocyte to granulosa cells that regulate their proliferation but also metabolites from the granulosa cells to the oocyte for biosynthesis. However, the underlying mechanism of establishing this communication is largely unknown. Here, we report that oocyte geranylgeranyl diphosphate (GGPP), a metabolic intermediate involved in protein geranylgeranylation, is required to establish the oocyte-granulosa cell communication. GGPP and geranylgeranyl diphosphate synthase (Ggpps) levels in oocytes increased during early follicular development. The selective depletion of GGPP in mouse oocytes impaired the proliferation of granulosa cells, primary-secondary follicle transition and female fertility. Mechanistically, GGPP depletion inhibited Rho GTPase geranylgeranylation and its GTPase activity, which was responsible for the accumulation of cell junction proteins in the oocyte cytoplasm and the failure to maintain physical connection between oocyte and granulosa cells. GGPP ablation also blocked Rab27a geranylgeranylation, which might account for the impaired secretion of oocyte materials such as Gdf9. Moreover, GGPP administration restored the defects in oocyte-granulosa cell contact, granulosa cell proliferation and primary-secondary follicle transition in Ggpps depletion mice. Our study provides the evidence that GGPP-mediated protein geranylgeranylation contributes to the establishment of oocyte-granulosa cell communication and then regulates the primary-secondary follicle transition, a key phase of folliculogenesis essential for female reproductive function.


Assuntos
Comunicação Celular , Farnesiltranstransferase/metabolismo , Células da Granulosa/metabolismo , Complexos Multienzimáticos/metabolismo , Oócitos/metabolismo , Folículo Ovariano/crescimento & desenvolvimento , Animais , Células Cultivadas , Farnesiltranstransferase/genética , Feminino , Fator 9 de Diferenciação de Crescimento/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Complexos Multienzimáticos/genética , Folículo Ovariano/citologia , Folículo Ovariano/metabolismo , Fosfatos de Poli-Isoprenil/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas rab de Ligação ao GTP/metabolismo , Proteínas rab27 de Ligação ao GTP
11.
J Clin Nurs ; 29(15-16): 2834-2848, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32320513

RESUMO

AIMS AND OBJECTIVES: To examine the influence of psycho-social and educational interventions on improving adherence to dialysis for patients with end-stage renal disease. BACKGROUND: Adherence to the complex regimen is poor, contributing to avoidable hospitalisation and morbidity. Psycho-social and educational interventions may be beneficial coping strategies. DESIGN: Systematic literature review and meta-analysis were conducted. METHODS: We conducted a systematic search of 8 databases from their inceptions to 16 January 2019 to identify relevant articles. Only randomised controlled trials (RCTs) were included in the analysis. The PRISMA checklist was used. RESULTS: A total of forty RCTs were included to evaluate the effect. The aggregated results of the studies showed that psycho-social and educational interventions elevated adherence rate in both peritoneal dialysis (PD) and haemodialysis (HD) patients. For physiological and biochemical indicators, meta-analysis revealed that significant post-treatment effects were evident for interdialytic weight gain (IDWG), IDWG/dry weight, serum potassium, phosphate, creatinine and blood urea nitrogen (BUN), except for albumin. In particular, subgroup analysis indicated that only the interventions carried out individually exerted significant combined effect for lowering IDWG. As for subjective measures, meta-analysis also revealed small but significant combined effects. CONCLUSIONS: The results of this meta-analysis suggest that psycho-social and educational interventions were associated with significant effects on adherence in patients receiving dialysis regimen. RELEVANCE TO CLINICAL PRACTICE: The analysis suggests that psycho-social and educational interventions should be considered as effective strategies for enhancing adherence to dialysis in adults with end-stage renal disease. The potential utility of these interventions should focus on how best to promote individually implementation in clinical practice.


Assuntos
Cooperação do Paciente , Educação de Pacientes como Assunto/métodos , Diálise Renal/psicologia , Adulto , Feminino , Humanos , Falência Renal Crônica/psicologia , Falência Renal Crônica/terapia , Masculino
12.
FASEB J ; 32(8): 4370-4379, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29543533

RESUMO

Postprandial insulin desensitization plays a critical role in maintaining whole-body glucose homeostasis by avoiding the excessive absorption of blood glucose; however, the detailed mechanisms that underlie how the major player, skeletal muscle, desensitizes insulin action remain to be elucidated. Herein, we report that early growth response gene-1 ( Egr-1) is activated by insulin in skeletal muscle and provides feedback inhibition that regulates insulin sensitivity after a meal. The inhibition of the transcriptional activity of Egr-1 enhanced the phosphorylation of the insulin receptor (InsR) and Akt, thus increasing glucose uptake in L6 myotubes after insulin stimulation, whereas overexpression of Egr-1 decreased insulin sensitivity. Furthermore, deletion of Egr-1 in the skeletal muscle improved systemic insulin sensitivity and glucose tolerance, which resulted in lower blood glucose levels after refeeding. Mechanistic analysis demonstrated that EGR-1 inhibited InsR phosphorylation and glucose uptake in skeletal muscle by binding to the proximal promoter region of protein tyrosine phosphatase-1B (PTP1B) and directly activating transcription. PTP1B knockdown largely restored insulin sensitivity and enhanced glucose uptake, even under conditions of EGR-1 overexpression. Our results indicate that EGR-1/PTP1B signaling negatively regulates postprandial insulin sensitivity and suggest a potential therapeutic target for the prevention and treatment of excessive glucose absorption.-Wu, J., Tao, W.-W., Chong, D.-Y., Lai, S.-S., Wang, C., Liu, Q., Zhang, T.-Y., Xue, B., Li, C.-J. Early growth response-1 negative feedback regulates skeletal muscle postprandial insulin sensitivity via activating Ptp1b transcription.


Assuntos
Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Insulina/metabolismo , Músculo Esquelético/metabolismo , Período Pós-Prandial/fisiologia , Proteína Tirosina Fosfatase não Receptora Tipo 1/metabolismo , Animais , Glicemia , Células Cultivadas , Glucose/metabolismo , Homeostase/fisiologia , Resistência à Insulina/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fibras Musculares Esqueléticas/metabolismo , Fosforilação/fisiologia , Ratos , Receptor de Insulina/metabolismo , Transdução de Sinais/fisiologia , Transcrição Gênica/fisiologia
13.
Nano Lett ; 18(2): 1296-1304, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29298076

RESUMO

The mechanical properties and plastic deformation mechanisms of metal nanowires have been studied intensely for many years. One of the important yet unresolved challenges in this field is to bridge the gap in properties and deformation mechanisms reported for slow strain rate experiments (∼10-2 s-1), and high strain rate molecular dynamics (MD) simulations (∼108 s-1) such that a complete understanding of strain rate effects on mechanical deformation and plasticity can be obtained. In this work, we use long time scale atomistic modeling based on potential energy surface exploration to elucidate the atomistic mechanisms governing a strain-rate-dependent incipient plasticity and yielding transition for face centered cubic (FCC) copper and silver nanowires. The transition occurs for both metals with both pristine and rough surfaces for all computationally accessible diameters (<10 nm). We find that the yield transition is induced by a transition in the incipient plastic event from Shockley partials nucleated on primary slip systems at MD strain rates to the nucleation of planar defects on non-Schmid slip planes at experimental strain rates, where multiple twin boundaries and planar stacking faults appear in copper and silver, respectively. Finally, we demonstrate that, at experimental strain rates, a ductile-to-brittle transition in failure mode similar to previous experimental studies on bicrystalline silver nanowires is observed, which is driven by differences in dislocation activity and grain boundary mobility as compared to the high strain rate case.

14.
J Headache Pain ; 20(1): 53, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31092190

RESUMO

BACKGROUND: Brainstem raphe (BR) hypoechogenicity in transcranial sonography (TCS) has been depicted in patients with major depression (MD) and in depressed patients with different neurodegenerative diseases. But, up to date, the association of BR alterations in TCS with depression in migraineurs has never been reported. This study was to investigate the possible role of BR examination via TCS in migraineurs with depression. METHODS: Forty two migraine without aura (MwoA) patients and 40 healthy controls were recruited. Echogenicity of lentiform nuclei (LN), caudate nuclei (CN), substantia nigra (SN) and brainstem raphe (BR) and width of the frontal horns of the lateral ventricles and the third ventricle were assessed with TCS. The diagnosis of depression was based on the criteria of the Diagnostic and Statistical Manual of Mental Disorders IV (DSM -IV), and the severity of depression was measured by Hamilton Rating Scale for Depression (HAM-D) and Hospital Anxiety and Depression Scale depression subscale (HADS-D). RESULTS: There were no significant differences between migraineurs and controls in the width of frontal horn of the lateral ventricle (p = 0.955), width of third ventricle (p = 0.129) as well as in the echogenicity of SN (p = 0.942), CN (p = 0.053), LN (p = 0.052) and BR (p = 0.677). Here, it seems that more migraineurs were detected with increased echogenecity of CN and LN compared with controls (33.3% versus 15.0% for CN, 19.0% versus 5.0% for LN) though they had no statistical significance. Patients with hypoechogenic BR had significantly higher HAM-D and HADS-D scores than those with normal BR signal (p = 0.000 for both HAM-D and HADS-D), and most (83.33%) migraineurs with depression exhibited hypoechogenic raphe but none (0.00%) of the migraineurs without depression exhibited hypoechogenic raphe (p = 0.000). CONLUSIONS: TCS signal alteration of BR can be a biomarker for depression in migraine but it is not associated with migraine headache itself. LN and CN alterations in TCS may reflect a potential role of them in the pathogenesis of migraine, which needs to be further elucidated.


Assuntos
Transtorno Depressivo/diagnóstico por imagem , Transtorno Depressivo/patologia , Transtornos de Enxaqueca/diagnóstico por imagem , Transtornos de Enxaqueca/patologia , Núcleos da Rafe/diagnóstico por imagem , Núcleos da Rafe/patologia , Adulto , Estudos de Casos e Controles , Depressão/diagnóstico por imagem , Depressão/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Ultrassonografia Doppler Transcraniana , Adulto Jovem
15.
Zhongguo Zhong Yao Za Zhi ; 44(3): 518-525, 2019 Feb.
Artigo em Zh | MEDLINE | ID: mdl-30989917

RESUMO

Based on the toxic characteristics caused by the compatibility between "Zaoji Suiyuan" and Glycyrrhizae Radix et Rhizoma, which was found in the previous studies, the expanded study was carried out on the incompatibility mechanism between Crotonis Semen Pulveratum(CT) and Glycyrrhizae Radix et Rhizoma(GU) with the diuretic effect and intestinal flora as the characteristic indexes. The results showed that GU could slow down the rapid diuretic effect of CT, which suggested a tendency of decreasing the efficacy. Both the high and low dose of CT could significantly induce the intestinal injury and change the intestinal bacteria structure of mice. Low dose CT combined with GU could significantly increase the levels of Streptococcus and Rikenellaceae_ukn. The relative abundance of Desulfovibrio and Streptococcaceae_ukn were increased after the combined application of high dose CT and GU. It also suggested that there was a risk of inflammation in the liver and intestines when combined application of these two herbs. The results revealed that the combination of CT and GU has a tendency to reduce the clinical effect and increase the toxicity from the aspects of its traditional efficacy and its effect on intestinal microflora structure, which could provide the data for the clinical use of CT.


Assuntos
Croton/química , Medicamentos de Ervas Chinesas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Glycyrrhiza/química , Animais , Diuréticos , Interações Medicamentosas , Intestinos , Camundongos , Raízes de Plantas/química
16.
BMC Ophthalmol ; 18(1): 286, 2018 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-30390645

RESUMO

BACKGROUND: To investigate thickness changes in the corneal epithelium and Bowman's layer after overnight silicone hydrogel contact lens (CL) wear by using ultra-high resolution optical coherence tomography (UHROCT). METHODS: Eleven subjects without CL wearing history were recruited for this study. An UHROCT was used to measure the thickness of the epithelium (ET), Bowman's layer (BT), stroma (ST), and total cornea (CCT) at the center of both eyes. A silicone hydrogel CL was inserted in the right eye of each subject, and the fellow non-CL wearing left eye served as the control. The lens was inserted at 9:30 pm and removed at 8:00 am the next morning. The subjects were evaluated at 9:00 pm (baseline), 9:30 pm (lens insertion), 10:00 pm (before sleep), 7:00 am (waking), 7:30 am, and 8:00 am (lens removal). RESULTS: Compared to the lens insertion level, the ET of the lens-wearing eye increased by 5.73% at eye opening (P = 0.001). The ET of the non-CL wearing eye and the BT in both eyes did not change after overnight CL wear. Compared to baseline, the CCT of the lens-wearing eye increased by 2.87% upon waking (P = 0.003) and recovered 30 min later (P = 0.555). In contrast, compared to baseline, the CCT of the non-CL wearing eye did not increase upon waking (P = 0.105). CONCLUSIONS: By using UHROCT, we found that overnight CL wear induced different swelling responses in the various sublayers of the cornea. TRIAL REGISTRATION: Retrospectively registered. Registration number: ChiCTR1800015115 . Registered 07 March 2018.


Assuntos
Lâmina Limitante Anterior/patologia , Lentes de Contato Hidrofílicas , Edema da Córnea/diagnóstico , Epitélio Corneano/patologia , Silicones , Adulto , Edema da Córnea/etiologia , Feminino , Seguimentos , Humanos , Masculino , Estudos Retrospectivos , Fatores de Tempo , Tomografia de Coerência Óptica
17.
Toxicol Mech Methods ; 28(4): 279-285, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29117763

RESUMO

This study was performed to investigate the action of pilose antler peptide (PAP) on high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) in rats. Animals were randomly divided into five groups: control group, model group receiving high-fat diet (HFD), atorvastatin group receiving high-fat diet (HFD) + atorvastatin (20 mg/kg), PAP-L group receiving HFD + PAP (50 mg/kg) and PAP-H group receiving HFD + DB (100 mg/kg). PAP administration significantly reduced the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), with improvement in liver histopathological examination. To further investigate the molecular mechanism of the effect of PAP on NAFLD, expression levels of AMP-activated protein kinase (AMPK)/NF-κB pathway in the liver were determined by western blot analysis, respectively. These results suggested that PAP administration was beneficial to treatments of NAFLD in rats fed HFD by modulating the expression levels of AMPK/NF-κB pathway.


Assuntos
Anti-Inflamatórios/uso terapêutico , Dieta Hiperlipídica/efeitos adversos , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Peptídeos/uso terapêutico , Animais , Citocinas/sangue , Modelos Animais de Doenças , Fígado/patologia , Testes de Função Hepática , Masculino , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/imunologia , Ratos Wistar
18.
Zhongguo Zhong Yao Za Zhi ; 43(2): 369-371, 2018 Jan.
Artigo em Zh | MEDLINE | ID: mdl-29552857

RESUMO

The study was based on the toxic characteristics of the compatibility between "Zaojisuiyuan" and Gancao, with intestinal tract and intestinal bacteria as subject. From the angle of intestinal barrier function, motor function, steady state of intestinal flora and metabolism genes, the toxic and side effects of the compatibility between Qianjinzi and Gancao with similar properties, bases and chemical composition and types were further explored. The results showed that the combined application of Qianjinzi and Gancao enhanced intestinal mucosa damage, and led to abnormal changes in intestinal bacteria structure and metabolic function. It improved the degradation functions of mucus and aromatic amino acids on intestinal bacteria, which may increase the risk of disease and derived from intestinal urotoxin and other toxic substances. This study considered intestinal bacteria as an important target to study the interactions of traditional Chinese medicine. The "drug-intestinal bacteria-metabolism-toxicity" was applied in the experiment. Meanwhile, it provides ideas for exploring incompatible mechanism of traditional Chinese medicines.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Glycyrrhiza uralensis/química , Mucosa Intestinal/efeitos dos fármacos , Animais , Mucosa Intestinal/patologia , Medicina Tradicional Chinesa
19.
J Pathol ; 238(1): 109-19, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26434932

RESUMO

Loss of first-phase insulin secretion associated with ß cell dysfunction is an independent predictor of type 2 diabetes mellitus (T2DM) onset. Here we found that a critical enzyme involved in protein prenylation, geranylgeranyl pyrophosphate synthase (GGPPS), is required to maintain first-phase insulin secretion. GGPPS shows a biphasic expression pattern in islets of db/db mice during the progression of T2DM: GGPPS is increased during the insulin compensatory period, followed by a decrease during ß cell dysfunction. Ggpps deletion in ß cells results in typical T2DM ß cell dysfunction, with blunted glucose-stimulated insulin secretion and consequent insulin secretion insufficiency. However, the number and size of islets and insulin biosynthesis are unaltered. Transmission electron microscopy shows a reduced number of insulin granules adjacent to the cellular membrane, suggesting a defect in docked granule pool formation, while the reserve pool is unaffected. Ggpps ablation depletes GGPP and impairs Rab27A geranylgeranylation, which is responsible for the docked pool deficiency in Ggpps-null mice. Moreover, GGPPS re-expression or GGPP administration restore glucose-stimulated insulin secretion in Ggpps-null islets. These results suggest that GGPPS-controlled protein geranylgeranylation, which regulates formation of the insulin granule docked pool, is critical for ß cell function and insulin release during the development of T2DM.


Assuntos
Linfócitos B/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Farnesiltranstransferase/metabolismo , Insulina/metabolismo , Complexos Multienzimáticos/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Animais , Western Blotting , Imunoprecipitação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Prenilação de Proteína/fisiologia , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real , Vesículas Secretórias/metabolismo , Vesículas Secretórias/ultraestrutura , Transfecção , Proteínas rab27 de Ligação ao GTP
20.
Support Care Cancer ; 25(7): 2335-2347, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28397023

RESUMO

PURPOSE: To assess the efficacy of non-pharmacological therapies for hot flushes (HFs) in women with breast cancer (BC). METHODS: Nine databases (MEDLINE, Cochrane Central Register of Controlled Trials, EMBASE, PsycINFO, CINAHL, China National Knowledge Infrastructure (CNKI), Chinese Scientific Journal Database (VIP), China Biology Medicine (CBM), and Wan Fang Database) were searched from their inceptions to October 2016. We also hand-searched reference lists of reviews and included articles, reviewed conference proceedings, and contacted experts. Finally, randomized controlled trials (RCTs) were aggregated to evaluate the therapeutic effect of acupuncture for HFs in women with BC. RESULTS: Sixteen trials were included in the meta-analysis. Significant combined effects of non-pharmacological therapies were observed in reducing frequency and severity of HFs after treatment (d = -0.57, P < 0.001). These effects were sustained, albeit reduced in part, during follow-up (d = -0.36, P < 0.001), with the exception of frequency (P = 0.41). Meta-analysis according to therapy types showed that for hypnosis, HFs scores instead of scores of HFs-related daily interference scale (HFRDIS) were significantly lowered at the post-treatment time point (d = -13.19, P < 0.001); for acupuncture, a small but significant effect on HFRDIS was found at the post-treatment time point (d = -3.34, P < 0.001). The effect was sustained during follow-up; however, no effect was evident for HFs frequency; for cognitive behavioral therapy (CBT), at the post-treatment time point, but not during follow-up, a small but significant effect was documented for HFs score (d = -0.88, P < 0.01). No serious adverse effect was reported in the included studies. CONCLUSIONS: Various types of non-pharmacological therapies were associated with significant effects on HFs in women with BC.


Assuntos
Neoplasias da Mama/terapia , Terapias Complementares/métodos , Fogachos/terapia , Feminino , Humanos
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