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1.
Hepatology ; 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38536017

RESUMO

BACKGROUND AND AIMS: We investigated whether empagliflozin reduces hepatic steatosis in patients with metabolic dysfunction-associated steatotic liver disease without diabetes mellitus. APPROACH AND RESULTS: This was an investigator-initiated, double-blind, randomized, placebo-controlled trial recruiting adult subjects from the community. Eligible subjects without diabetes mellitus (fasting plasma glucose < 7 mmol/L and HbA1c < 6.5%) who had magnetic resonance imaging-proton density fat fraction (MRI-PDFF) ≥ 5% were randomly allocated to receive empagliflozin 10 mg daily or placebo (1:1 ratio) for 52 weeks (end of treatment, EOT). MRI-PDFF was conducted at baseline and EOT. The primary outcome was the difference in change of MRI-PDFF between the 2 groups at EOT. Secondary outcomes were hepatic steatosis resolution (MRI-PDFF < 5%), alanine aminotransferase drop ≥ 17 U/L, MRI-PDFF decline ≥ 30%, a combination of both, and changes of anthropometric and laboratory parameters at EOT. All outcomes were based on intention-to-treat analysis. Of 98 recruited subjects (median age: 55.7 y [IQR:49.5-63.4]; male:54 [55.1%]), 97 (empagliflozin:49, placebo:48; median MRI-PDFF:9.7% vs 9.0%) had MRI-PDFF repeated at EOT. The Empagliflozin group had a greater reduction in median MRI-PDFF compared to the placebo group (-2.49% vs. -1.43%; p = 0.025), with a nonsignificant trend of resolution of hepatic steatosis (44.9% vs. 28.6%; p = 0.094). There was no significant difference in alanine aminotransferase drop ≥ 17 U/L (16.3% vs. 12.2%; p = 0.564), MRI-PDFF drop ≥ 30% (49.0% vs. 40.8%; p = 0.417), and composite outcome (8.2% vs. 8.2%; p = 1.000). Empagliflozin group had a greater drop in body weight (-2.7 vs. -0.2 kg), waist circumference (-2.0 vs. 0 cm), fasting glucose (-0.3 vs. 0 mmol/L), and ferritin (-126 vs. -22 pmol/L) (all p < 0.05). CONCLUSIONS: Empagliflozin for 52 weeks reduces hepatic fat content in subjects with nondiabetic metabolic dysfunction-associated steatotic liver disease. (ClinicalTrials.gov Identifier: NCT04642261).

2.
J Neuroinflammation ; 20(1): 71, 2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36915108

RESUMO

BACKGROUND: Systemic activation of the immune system can exert detrimental effects on the central nervous system. Periodontitis, a chronic disease of the oral cavity, is a common source of systemic inflammation. Neuroinflammation might be a result of this to accelerate progressive deterioration of neuronal functions during aging or exacerbate pre-existing neurodegenerative diseases, such as Alzheimer's disease. With advancing age, the progressive increase in the body's pro-inflammatory status favors the state of vulnerability to both periodontitis and Alzheimer's disease. In the present study, we sought to delineate the roles of cytokines in the pathogenesis of both diseases. METHODS: To examine the impacts of periodontitis on the onset and progression of Alzheimer's disease, 6-month-old female 3 × Tg-AD mice and their age-matched non-transgenic mice were employed. Periodontitis was induced using two different experimental models: heat-killed bacterial-induced periodontitis and ligature-induced periodontitis. To delineate the roles of pro-inflammatory cytokines in the pathogenesis of periodontitis and Alzheimer's disease, interleukin 1 beta (IL-1ß) and tumor necrosis factor-alpha (TNF-α) were also injected into the buccal mandibular vestibule of mice. RESULTS: Here, we show that IL-1ß and TNF-α were two of the most important and earliest cytokines upregulated upon periodontal infection. The systemic upregulation of these two cytokines promoted a pro-inflammatory environment in the brain contributing to the development of Alzheimer's disease-like pathology and cognitive dysfunctions. Periodontitis-induced systemic inflammation also enhanced brain inflammatory responses and subsequently exacerbated Alzheimer's disease pathology and cognitive impairment in 3 × Tg-AD mice. The role of inflammation in connecting periodontitis to Alzheimer's disease was further affirmed in the conventional magnetization transfer experiment in which increased glial responses resulting from periodontitis led to decreased magnetization transfer ratios in the brain of 3 × Tg-AD mice. CONCLUSIONS: Systemic inflammation resulting from periodontitis contributed to the development of Alzheimer's disease tau pathology and subsequently led to cognitive decline in non-transgenic mice. It also potentiated Alzheimer's disease pathological features and exacerbated impairment of cognitive function in 3 × Tg-AD mice. Taken together, this study provides convincing evidence that systemic inflammation serves as a connecting link between periodontitis and Alzheimer's disease.


Assuntos
Doença de Alzheimer , Periodontite , Feminino , Camundongos , Animais , Fator de Necrose Tumoral alfa , Doença de Alzheimer/patologia , Interleucina-1beta , Inflamação , Citocinas , Camundongos Transgênicos
3.
J Biomed Sci ; 29(1): 15, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35189880

RESUMO

The increasing amount of particulate matter (PM) in the ambient air is a pressing public health issue globally. Epidemiological studies involving data from millions of patients or volunteers have associated PM with increased risk of dementia and Alzheimer's disease in the elderly and cognitive dysfunction and neurodegenerative pathology across all age groups, suggesting that PM may be a risk factor for neurodegenerative diseases. Neurodegenerative diseases affect an increasing population in this aging society, putting a heavy burden on economics and family. Therefore, understanding the mechanism by which PM contributes to neurodegeneration is essential to develop effective interventions. Evidence in human and animal studies suggested that PM induced neurodenegerative-like pathology including neurotoxicity, neuroinflammation, oxidative stress, and damage in blood-brain barrier and neurovascular units, which may contribute to the increased risk of neurodegeneration. Interestingly, antagonizing oxidative stress alleviated the neurotoxicity of PM, which may underlie the essential role of oxidative stress in PM's potential effect in neurodegeneration. This review summarized up-to-date epidemiological and experimental studies on the pathogenic role of PM in neurodegenerative diseases and discussed the possible underlying mechanisms.


Assuntos
Doença de Alzheimer , Material Particulado , Idoso , Envelhecimento , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/etiologia , Animais , Humanos , Estresse Oxidativo , Material Particulado/toxicidade
4.
Radiology ; 300(1): 237-242, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34152855

RESUMO

History A 46-year-old woman with known mixed connective tissue disease with clinical features of scleroderma and polymyositis and who was not on specific medications was referred to our institution to assess for interstitial lung disease due to her predisposing condition. She was a nonsmoker, had no respiratory symptoms, and enjoyed good exercise tolerance. She did not have any cutaneous lesions or renal disease. There was no family history of pulmonary or systemic disease. Her routine blood test results revealed a white blood cell count of 4.6 × 109/L (normal range, [4.4-10.1] × 109/L), a hemoglobin level of 7.76 mmol/L (normal range, 7.26-9.18 mmol/L), a platelet count of 189 × 109/L (normal range, [170-380] × 109/L), a bilirubin level of 8 mmol/L (normal range, <19 mmol/L), and a creatinine level of 63 mmol/L (normal range, 45-82 mmol/L), all within normal limits. Lung function tests at presentation yielded normal results, with a diffusing capacity for carbon monoxide of 95% and a forced vital capacity of 2.29 (98% predicted value). However, this patient had an elevated serum globulin level of 47 g/L (normal range, 26-32 g/L) and an erythrocyte sedimentation rate of 36 mm/h (normal range, 0-20 mm/h), while C-reactive protein level was normal at less than 0.35 mg/dL. She was seropositive for antinuclear (titer >1/720), anti-Ro, anti-La, and anti-extractable nuclear antigen antibodies. Chest radiography and CT were performed at presentation and 14-year follow-up. PET/CT was performed at 7- and 13-year follow-up. Throughout this 14-year follow-up period, she remained completely free of respiratory symptoms and continued to go for a brisk walk every day. At 14-year follow-up, there was no substantial change in serum laboratory values, but a lung function test revealed her diffusing capacity for carbon monoxide had decreased to 52%, while her forced vital capacity remained good at 95%; these findings were suggestive of interval development of restrictive lung function.


Assuntos
Amiloidose/diagnóstico por imagem , Cistos/diagnóstico por imagem , Pneumopatias/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Linfoma de Zona Marginal Tipo Células B/diagnóstico por imagem , Biomarcadores/sangue , Diagnóstico Diferencial , Progressão da Doença , Feminino , Humanos , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Radiografia Torácica , Testes de Função Respiratória , Tomografia Computadorizada por Raios X
5.
Radiology ; 298(3): 707-712, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33617418

RESUMO

History A 46-year-old woman with known mixed connective tissue disease with clinical features of scleroderma and polymyositis and who was not on specific medications was referred to our institution to assess for interstitial lung disease due to her predisposing condition. She was a nonsmoker, had no respiratory symptoms, and enjoyed good exercise tolerance. She did not have any cutaneous lesions or renal disease. There was no family history of pulmonary or systemic disease. Her routine blood test results revealed a white blood cell count of 4.6 × 109/L (normal range, [4.4-10.1] × 109/L), a hemoglobin level of 7.76 mmol/L (normal range, 7.26-9.18 mmol/L), a platelet count of 189 × 109/L (normal range, [170-380] × 109/L), a bilirubin level of 8 µmol/L (7-19 µmol/L), and a creatinine level of 63 µmol/L (45-82 µmol/L), all within normal limits. Lung function tests at presentation yielded normal results, with a diffusing capacity for carbon monoxide of 95% and a forced vital capacity of 2.29 (98% predicted value). However, this patient had an elevated serum globulin level of 47 g/L (normal range, 26-32 g/L) and an erythrocyte sedimentation rate of 36 mm/h (normal range, 0-20 mm/h), while C-reactive protein level was normal at less than 0.35 mg/dL. She was seropositive for antinuclear (titer >1/720), anti-Ro, anti-La, and anti-extractable nuclear antigen antibodies. Chest radiography and CT were performed at presentation (Figs 1, 2) and 14-year follow-up (Figs 3, 4). PET/CT was performed at 7- (Fig 5, A and B) and 13-year follow-up (Fig 5, C and D). Throughout this 14-year follow-up period, she remained completely free of respiratory symptoms and continued to go for a brisk walk every day. At 14-year follow-up, there was no substantial change in serum laboratory values, but a lung function test revealed her diffusing capacity for carbon monoxide had decreased to 52%, while her forced vital capacity remained good at 95%; these findings were suggestive of interval development of restrictive lung function.

6.
Neuropathol Appl Neurobiol ; 47(3): 441-453, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33107057

RESUMO

AIMS: A variety of tissue clearing techniques have been developed to render intact tissue transparent. For thicker samples, additional partial tissue delipidation is required before immersion into the final refractive index (RI)-matching solution, which alone is often inadequate to achieve full tissue transparency. However, it is difficult to determine a sufficient degree of tissue delipidation, excess of which can result in tissue distortion and protein loss. Here, we aim to develop a clearing strategy that allows better monitoring and more precise determination of delipidation progress. METHODS: We combined the detergent sodium dodecyl sulphate (SDS) with OPTIClear, a RI-matching solution, to form a strategy termed Accurate delipidation with Optimal Clearing (Accu-OptiClearing). Accu-OptiClearing allows for a better preview of the final tissue transparency achieved when immersed in OPTIClear alone just before imaging. We assessed for the changes in clearing rate, protein loss, degree of tissue distortion, and preservation of antigens. RESULTS: Partial delipidation using Accu-OptiClearing accelerated tissue clearing and better preserved tissue structure and antigens than delipidation with SDS alone. Despite achieving similar transparency in the final OPTIClear solution, more lipids were retained in samples cleared with Accu-OptiClearing compared to SDS. CONCLUSIONS: Combining the RI-matching solution OPTIClear with detergents, Accu-OptiClearing, can avoid excessive delipidation, leading to accelerated tissue clearing, less tissue damage and better preserved antigens.


Assuntos
Encéfalo , Técnicas de Preparação Histocitológica/métodos , Imageamento Tridimensional/métodos , Animais , Artefatos , Feminino , Masculino , Camundongos , Microscopia Confocal/métodos , Ratos , Ratos Sprague-Dawley , Dodecilsulfato de Sódio , Tensoativos , Peixe-Zebra
7.
Front Neuroendocrinol ; 54: 100764, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31102663

RESUMO

Emerging evidence suggests that sleep deprivation (SD) and circadian rhythm disruption (CRD) may interact and increase the risk for the development of Alzheimer's disease (AD). This review inspects different pathophysiological aspects of SD and CRD, and shows that the two may impair the glymphatic-vascular-lymphatic clearance of brain macromolecules (e.g., ß-amyloid and microtubule associated protein tau), increase local brain oxidative stress and diminish circulatory melatonin levels. Lastly, this review looks into the potential association between sleep and circadian rhythm with stress granule formation, which might be a new mechanism along the AD pathogenic pathway. In summary, SD and CRD is likely to be associated with a positive risk in developing Alzheimer's disease in humans.


Assuntos
Doença de Alzheimer/etiologia , Ritmo Circadiano/fisiologia , Sistema Glinfático , Melatonina/metabolismo , Estresse Oxidativo/fisiologia , Privação do Sono/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Sistema Glinfático/metabolismo , Sistema Glinfático/fisiopatologia , Humanos , Privação do Sono/complicações
8.
Radiology ; 296(2): E72-E78, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32216717

RESUMO

Background Current coronavirus disease 2019 (COVID-19) radiologic literature is dominated by CT, and a detailed description of chest radiography appearances in relation to the disease time course is lacking. Purpose To describe the time course and severity of findings of COVID-19 at chest radiography and correlate these with real-time reverse transcription polymerase chain reaction (RT-PCR) testing for severe acute respiratory syndrome coronavirus 2, or SARS-CoV-2, nucleic acid. Materials and Methods This is a retrospective study of patients with COVID-19 confirmed by using RT-PCR and chest radiographic examinations who were admitted across four hospitals and evaluated between January and March 2020. Baseline and serial chest radiographs (n = 255) were reviewed with RT-PCR. Correlation with concurrent CT examinations (n = 28) was performed when available. Two radiologists scored each chest radiograph in consensus for consolidation, ground-glass opacity, location, and pleural fluid. A severity index was determined for each lung. The lung scores were summed to produce the final severity score. Results The study was composed of 64 patients (26 men; mean age, 56 years ± 19 [standard deviation]). Of these, 58 patients had initial positive findings with RT-PCR (91%; 95% confidence interval: 81%, 96%), 44 patients had abnormal findings at baseline chest radiography (69%; 95% confidence interval: 56%, 80%), and 38 patients had initial positive findings with RT-PCR testing and abnormal findings at baseline chest radiography (59%; 95% confidence interval: 46%, 71%). Six patients (9%) showed abnormalities at chest radiography before eventually testing positive for COVID-19 with RT-PCR. Sensitivity of initial RT-PCR (91%; 95% confidence interval: 83%, 97%) was higher than that of baseline chest radiography (69%; 95% confidence interval: 56%, 80%) (P = .009). Radiographic recovery (mean, 6 days ± 5) and virologic recovery (mean, 8 days ± 6) were not significantly different (P = .33). Consolidation was the most common finding (30 of 64; 47%) followed by ground-glass opacities (21 of 64; 33%). Abnormalities at chest radiography had a peripheral distribution (26 of 64; 41%) and lower zone distribution (32 of 64; 50%) with bilateral involvement (32 of 64; 50%). Pleural effusion was uncommon (two of 64; 3%). The severity of findings at chest radiography peaked at 10-12 days from the date of symptom onset. Conclusion Findings at chest radiography in patients with coronavirus disease 2019 frequently showed bilateral lower zone consolidation, which peaked at 10-12 days from symptom onset. © RSNA, 2020.


Assuntos
Betacoronavirus , Infecções por Coronavirus/diagnóstico por imagem , Pneumonia Viral/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19 , Teste para COVID-19 , Vacinas contra COVID-19 , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/virologia , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2 , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
9.
Phys Chem Chem Phys ; 22(13): 7100-7109, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32202576

RESUMO

The contact resistance (Rc) and the effective carrier mobility (µeff) are considered as the important indicators of the performance of organic field-effect transistors (OFETs). Conventionally, the contact resistance is regarded as the interface effect between the metal electrodes and the organic semiconductors, while the carrier mobility is correlated to the crystallinity and π-π stacking of the organic molecules. In the staggered OFETs, Rc is actually closely correlated to µeff through the channel sheet resistance. Besides, the accuracy of the carrier mobility directly extracted from the non-ideal transfer curves with significant contact effect is always questionable. Herein, a diffusion-lead surface doping approach is employed to improve the contact resistance and mobility issues simultaneously. By suppressing the trap states in the sublimated 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) organic semiconductor with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), we observed a 3-fold increase in the carrier mobility from 0.5 to 1.6 cm2 V-1 s-1, and the Rc also drops remarkably from 25.7 kΩ cm to 5.2 kΩ cm. Moreover, the threshold voltage (VTH), subthreshold swing (SS) and the bias stability of the OFETs are also significantly improved. Based on the detailed characterization of the C8-BTBT film upon surface doping, including X-ray diffraction (XRD) for the film crystallinity, Kelvin probe force microscopy (KPFM) for the surface potential, trap state investigation by density of states (DOS) measurement and electrical circuit modeling for partial doping analysis, we confirmed that the spontaneous charge transfer process due to the diffusion of the F4-TCNQ dopants in the C8-BTBT matrix can lead to an effective trap filling. This technique and findings can be potentially developed into a general approach for the improvement of different performance parameters of OFETs.

10.
Surg Endosc ; 34(8): 3382-3387, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31506793

RESUMO

BACKGROUND: The transection of rectum and fashioning of anastomosis is a crucial step in laparoscopic total mesorectal excision (TME) and the double-stapling technique (DST) is often employed. This study aimed to evaluate the factors that were associated with difficult DST. METHOD: Cases of laparoscopic TME were retrospectively reviewed. The clinico-anatomical parameters were retrieved from a prospectively maintained database. In addition, pelvic dimensions were taken by reviewing the magnetic resonance imaging scan. The number of stapler cartridges used for intracorporeal transection of rectum was used as a surrogate for the level of difficulty of DST and its relationship with various parameters were evaluated. RESULTS: There were a total of 121 consecutive cases analyzed. The mean number of stapler cartridges used was 2.1 ± 0.7. Pelvic inlet (p = 0.002) and tumor height (p = 0.015) were predictors of the number of cartridges used, R2 = 0.366. A model was developed to predict the likelihood of transecting the rectum with two or less stapler cartridges, which included the following parameters: gender, pelvic inlet, interspinous distance, intertuberous distance, and tumor height. The predicted probability also correlated with overall operation time (p = 0.009) and anastomotic leakage (p = 0.023). CONCLUSION: The difficulty of DST was associated with patient's clinico-anatomical factors. Surgeons can consider other feasible alternatives, like transanal anastomosis, when a technically challenging DST is anticipated.


Assuntos
Anastomose Cirúrgica , Laparoscopia , Reto/cirurgia , Grampeamento Cirúrgico , Anastomose Cirúrgica/métodos , Anastomose Cirúrgica/estatística & dados numéricos , Humanos , Laparoscopia/métodos , Laparoscopia/estatística & dados numéricos , Duração da Cirurgia , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Grampeamento Cirúrgico/efeitos adversos , Grampeamento Cirúrgico/classificação , Grampeamento Cirúrgico/métodos , Grampeamento Cirúrgico/estatística & dados numéricos
11.
Lab Invest ; 99(7): 943-957, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30808929

RESUMO

Growing evidence has shown the beneficial influence of exercise on humans. Apart from classic cardioprotection, numerous studies have demonstrated that different exercise regimes provide a substantial improvement in various brain functions. Although the underlying mechanism is yet to be determined, emerging evidence for neuroprotection has been established in both humans and experimental animals, with most of the valuable findings in the field of mental health, neurodegenerative diseases, and acquired brain injuries. This review will discuss the recent findings of how exercise could ameliorate brain function in neuropathological states, demonstrated by either clinical or laboratory animal studies. Simultaneously, state-of-the-art molecular mechanisms underlying the exercise-induced neuroprotective effects and comparison between different types of exercise will be discussed in detail. A majority of reports show that physical exercise is associated with enhanced cognition throughout different populations and remains as a fascinating area in scientific research because of its universal protective effects in different brain domain functions. This article is to review what we know about how physical exercise modulates the pathophysiological mechanisms of neurodegeneration.


Assuntos
Encefalopatias/terapia , Encéfalo/fisiologia , Terapia por Exercício , Exercício Físico/fisiologia , Doenças Neurodegenerativas/terapia , Animais , Humanos , Transtornos Mentais/terapia , Doenças Neurodegenerativas/metabolismo , Condicionamento Físico Animal/fisiologia
12.
Brain Behav Immun ; 81: 63-73, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31279681

RESUMO

Persistent inflammation in the systemic immune system can impose detrimental effects on the central nervous system (CNS). Neuroinflammation might be a result of this to accelerate the progressive deterioration of neuronal functions during aging. In this regard, controlling inflammation through delaying and/or preventing chronic inflammatory diseases may be a potential strategy to prevent or modify the progression of Alzheimer's Disease (AD). Periodontitis is a chronic inflammatory disease of the oral cavity that is common among the elderly, especially for those who have decline in cognitive functions. While epidemiological findings support the association of chronic periodontitis and cognitive decline, whether they have causal relationship remains unclear. Nonetheless, the possibility that periodontopathogens, systemic immune cells and inflammatory cytokines could reach the CNS should not be overlooked. The impacts of periodontitis on CNS homeostasis and inflammation as a pathophysiological factor concerning the association between periodontitis and AD will be discussed in this review. Future work should elucidate the pathological pathways involved in periodontitis-induced cerebral infections and inflammation, and define the role of the latter in AD progression.


Assuntos
Periodontite Crônica/imunologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/imunologia , Idoso , Doença de Alzheimer/metabolismo , Barreira Hematoencefálica/imunologia , Doença Crônica , Periodontite Crônica/fisiopatologia , Cognição/fisiologia , Disfunção Cognitiva/complicações , Citocinas/imunologia , Progressão da Doença , Humanos , Inflamação/complicações , Neuroimunomodulação/imunologia , Fatores de Risco
13.
Part Fibre Toxicol ; 15(1): 28, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29970116

RESUMO

BACKGROUND: Silica nanoparticles (SiO2-NPs) are naturally enriched and broadly utilized in the manufacturing industry. While previous studies have demonstrated toxicity in neuronal cell lines after SiO2-NPs exposure, the role of SiO2-NPs in neurodegeneration is largely unknown. Here, we evaluated the effects of SiO2-NPs-exposure on behavior, neuropathology, and synapse in young adult mice and primary cortical neuron cultures. RESULTS: Male C57BL/6 N mice (3 months old) were exposed to either vehicle (sterile PBS) or fluorescein isothiocyanate (FITC)-tagged SiO2-NPs (NP) using intranasal instillation. Behavioral tests were performed after 1 and 2 months of exposure. We observed decreased social activity at both time points as well as anxiety and cognitive impairment after 2 months in the NP-exposed mice. NP deposition was primarily detected in the medial prefrontal cortex and the hippocampus. Neurodegeneration-like pathological changes, including reduced Nissl staining, increased tau phosphorylation, and neuroinflammation, were also present in the brains of NP-exposed mice. Furthermore, we observed NP-induced impairment in exocytosis along with decreased synapsin I and increased synaptophysin expression in the synaptosome fractions isolated from the frontal cortex as well as primary neuronal cultures. Extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) were also activated in the frontal cortex of NP-exposed mice. Moreover, inhibition of ERK activation prevented NP-mediated changes in exocytosis in cultured neurons, highlighting a key role in the changes induced by NP exposure. CONCLUSIONS: Intranasal instillation of SiO2-NPs results in mood dysfunction and cognitive impairment in young adult mice and causes neurodegeneration-like pathology and synaptic changes via ERK activation.


Assuntos
Comportamento Animal/efeitos dos fármacos , Exposição por Inalação/efeitos adversos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Nanopartículas/toxicidade , Neurônios/efeitos dos fármacos , Dióxido de Silício/toxicidade , Sinapses/efeitos dos fármacos , Animais , Exocitose/efeitos dos fármacos , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/patologia , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Masculino , Camundongos Endogâmicos C57BL , Neurônios/patologia , Tamanho da Partícula , Propriedades de Superfície , Sinapses/enzimologia , Sinapses/patologia
14.
Proc Natl Acad Sci U S A ; 112(29): E3959-68, 2015 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-26150509

RESUMO

Land plants develop filamentous cells-root hairs, rhizoids, and caulonemata-at the interface with the soil. Members of the group XI basic helix-loop-helix (bHLH) transcription factors encoded by LOTUS JAPONICUS ROOTHAIRLESS1-LIKE (LRL) genes positively regulate the development of root hairs in the angiosperms Lotus japonicus, Arabidopsis thaliana, and rice (Oryza sativa). Here we show that auxin promotes rhizoid and caulonema development by positively regulating the expression of PpLRL1 and PpLRL2, the two LRL genes in the Physcomitrella patens genome. Although the group VIII bHLH proteins, AtROOT HAIR DEFECTIVE6 and AtROOT HAIR DEFECTIVE SIX-LIKE1, promote root-hair development by positively regulating the expression of AtLRL3 in A. thaliana, LRL genes promote rhizoid development independently of PpROOT HAIR DEFECTIVE SIX-LIKE1 and PpROOT HAIR DEFECITVE SIX-LIKE2 (PpRSL1 and PpRSL2) gene function in P. patens. Together, these data demonstrate that both LRL and RSL genes are components of an ancient auxin-regulated gene network that controls the development of tip-growing cells with rooting functions among most extant land plants. Although this network has diverged in the moss and the angiosperm lineages, our data demonstrate that the core network acted in the last common ancestor of the mosses and angiosperms that existed sometime before 420 million years ago.


Assuntos
Bryopsida/citologia , Bryopsida/genética , Sequência Conservada , Regulação da Expressão Gênica de Plantas , Raízes de Plantas/fisiologia , Sequência de Aminoácidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Teorema de Bayes , Bryopsida/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas , Glucuronidase/metabolismo , Ácidos Indolacéticos/farmacologia , Funções Verossimilhança , Modelos Biológicos , Dados de Sequência Molecular , Mutação/genética , Fenótipo , Fosfatos/farmacologia , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Alinhamento de Sequência
15.
Mol Pharmacol ; 91(5): 499-517, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28275050

RESUMO

Tumor necrosis factor α (TNFα) plays a vital role in cancer progression as it is associated with inflammation and promotion of cancer angiogenesis and metastasis. The effects of TNFα are mediated by its downstream target, the oncogene lysine-rich CEACAM1 coisolated protein (LYRIC, also known as metadherin or astrocyte elevated gene-1). LYRIC plays an important role in activating the nuclear factor-ĸB (NF-κB) signaling pathway, which controls multiple cellular processes, including proliferation, apoptosis, migration, etc. In contrast, the metastasis suppressor N-myc downstream regulated gene 1 (NDRG1) has the opposite effect on the NF-κB pathway, being able to inhibit NF-κB activation and reduce angiogenesis, proliferation, migration, and cancer cell invasion. These potent anticancer properties make NDRG1 an ideal therapeutic target. Indeed, a novel class of thiosemicarbazone anticancer agents that target this molecule has been developed; the lead agent, di-2-pyridylketone 4-cyclohexyl-4-methyl-3-thiosemicarbazone, has recently entered clinical trials for advanced and resistant cancers. To further elucidate the interaction between NDRG1 and oncogenic signaling, this study for the first time assessed the effects of NDRG1 on the tumorigenic properties of TNFα and its downstream target, LYRIC. We have demonstrated that NDRG1 inhibits the TNFα-mediated epithelial-to-mesenchymal transition. Further, NDRG1 also potently inhibited LYRIC expression, with a negative feedback loop existing between these two molecules. Examining the mechanism involved, we demonstrated that NDRG1 inhibited phosphatidylinositol 3-kinase/AKT signaling, leading to reduced levels of the LYRIC transcriptional activator, c-Myc. Finally, we demonstrated that novel thiosemicarbazones that upregulate NDRG1 also inhibit LYRIC expression, further highlighting their marked potential for cancer treatment.


Assuntos
Moléculas de Adesão Celular/metabolismo , Proteínas de Ciclo Celular/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Tiossemicarbazonas/farmacologia , Regulação para Cima/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Desferroxamina/farmacologia , Inativação Gênica/efeitos dos fármacos , Humanos , Proteínas de Membrana , Modelos Biológicos , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transporte Proteico/efeitos dos fármacos , Proteínas de Ligação a RNA , Tiossemicarbazonas/química , Fator de Necrose Tumoral alfa/farmacologia , Vimentina/metabolismo
16.
Adv Mar Biol ; 73: 27-64, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26790887

RESUMO

In coastal waters of the Pearl River Delta (PRD) region, the Indo-Pacific humpback dolphin (Sousa chinensis) is thought to number approximately 2500 individuals. Given these figures, the putative PRD population may appear strong enough to resist demographic stochasticity and environmental pressures. However, living in close proximity to the world's busiest seaport/airport and several densely populated urban centres with major coastal infrastructural developments comes with challenges to the long-term survival of these animals. There are few other small cetacean populations that face the range and intensity of human-induced pressures as those present in the PRD and current protection measures are severely inadequate. Recent mark-recapture analyses of the animals in Hong Kong waters indicate that in the past two decades the population parameters have not been well understood, and spatial analyses show that only a very small proportion of the dolphins' key habitats are given any form of protection. All current marine protected areas within the PRD fail to meet a minimum habitat requirement that could facilitate the population's long-term persistence. Demographic models indicate a continuous decline of 2.5% per annum, a rate at which the population is likely to drop below the demographic threshold within two generations and lose 74% of the current numbers within the lifespan of three generations. In Hong Kong, the case of humpback dolphins represents a particularly explicit example of inadequate management where a complete revision of the fundamental approach to conservation management is urgently needed.


Assuntos
Distribuição Animal , Conservação dos Recursos Naturais , Golfinhos/fisiologia , Espécies em Perigo de Extinção , Rios , Animais , China , Ecossistema , Feminino , Hong Kong , Atividades Humanas , Masculino , Reprodução/fisiologia
17.
Molecules ; 21(11)2016 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-27879670

RESUMO

Icariin, an ingredient in the medicinal herb Epimedium brevicornum Maxim (EbM), has been considered as a potential therapeutic agent for neurodegenerative diseases such as Alzheimer's disease (AD). Hyperhomocysteinaemia is a risk factor for AD and other associated neurological diseases. In this study we aim to investigate whether icariin can reverse homocysteine (Hcy)-induced neurotoxicity in primary embryonic cultures of rat cortical neurons. Our findings demonstrated that icariin might be able restore the cytoskeleton network damaged by Hcy through the modulation of acetyl-α-tubulin, tyrosinated-α-tubulin, and phosphorylation of the tubulin-binding protein Tau. In addition, icariin downregulated p-extracellular signal-regulated kinase (ERK) which is a kinase targeting tau protein. Furthermore, icariin effectively restored the neuroprotective protein p-Akt that was downregulated by Hcy. We also applied RT² Profiler PCR Arrays focused on genes related to AD and neurotoxicity to examine genes differentially altered by Hcy or icariin. Among the altered genes from the arrays, ADAM9 was downregulated 15 folds in cells treated with Hcy, but markedly restored by icariin. ADAM family, encoded α-secreatase, plays a protective role in AD. Overall, our findings demonstrated that icariin exhibits a strong neuroprotective function and have potential for future development for drug treating neurological disorders, such as AD.


Assuntos
Embrião de Mamíferos/citologia , Flavonoides/farmacologia , Homocisteína/efeitos adversos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Proteínas ADAM/genética , Animais , Células Cultivadas , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Modelos Biológicos , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
18.
J Neuroinflammation ; 12: 212, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26585788

RESUMO

BACKGROUND: Systemic inflammation induces neuroimmune activation, ultimately leading to sickness (e.g., fever, anorexia, motor impairments, exploratory deficits, and social withdrawal). In this study, we evaluated the role of protein kinase R (PKR), a serine-threonine kinase that can control systemic inflammation, on neuroimmune responses and sickness. METHODS: Wild-type (WT) PKR+/+ mice and PKR-/- mice were subcutaneously injected with live Escherichia coli (E. coli) or vehicle. Food consumption, rotarod test performance, burrowing, open field activity, object investigation, and social interaction were monitored. Plasma TNF-α and corticosterone were measured by ELISA. The percentage of neutrophils in blood was deduced from blood smears. Inflammatory gene expression (IL-1ß, TNF-α, IL-6, cyclooxygenase (COX)-2, iNOS) in the liver and the brain (hypothalamus and hippocampus) were quantified by real-time PCR. Blood and lavage fluid (injection site) were collected for microbiological plate count and for real-time PCR of bacterial 16S ribosomal DNA (rDNA). Corticotrophin-releasing hormone (CRH) expression in the hypothalamus was also determined by real-time PCR. RESULTS: Deficiency of PKR diminished peripheral inflammatory responses following E. coli challenge. However, while the core components of sickness (anorexia and motor impairments) were similar between both strains of mice, the behavioral components of sickness (reduced burrowing, exploratory activity deficits, and social withdrawal) were only observable in PKR-/- mice but not in WT mice. Such alteration of behavioral components was unlikely to be caused by exaggerated neuroimmune activation, by an impaired host defense to the infection, or due to a dysregulated corticosterone response, because both strains of mice displayed similar neuroimmune responses, bacterial titers, and plasma corticosterone profiles throughout the course of infection. Nevertheless, the induction of hypothalamic corticotrophin-releasing hormone (CRH) by E. coli was delayed in PKR-/- mice relative to WT mice, suggesting that PKR deficiency may postpone the CRH response during systemic inflammation. CONCLUSIONS: Taken together, our findings show that (1) loss of PKR could alter E. coli-induced sickness behaviors and (2) this was unlikely to be due to exacerbated neuroimmune activation, (3) elevated bacterial load, or (4) dysregulation in the corticosterone response. Further studies can address the role of PKR in the CRH response together with its consequence on sickness.


Assuntos
Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/psicologia , eIF-2 Quinase/genética , Animais , Carga Bacteriana , Comportamento Animal , Química Encefálica/genética , Corticosterona/sangue , Citocinas/sangue , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neutrófilos , RNA Ribossômico 16S/genética , Receptores de Hormônio Liberador da Corticotropina/biossíntese , Receptores de Hormônio Liberador da Corticotropina/genética , Fator de Necrose Tumoral alfa/sangue
19.
BJU Int ; 116(3): 382-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25327618

RESUMO

OBJECTIVE: To investigate the risk of acute myocardial infarction (AMI) after androgen-deprivation therapy (ADT) for prostate cancer in a Chinese population. PATIENTS AND METHODS: All Chinese patients with prostate cancer who were treated primarily with radical prostatectomy or radiotherapy, with or without further ADT at our hospital from the year 2000 to 2009 were retrospectively reviewed. We compared the risk of AMI in the patients who were given further ADT (ADT group) with those who were not given any ADT (non-ADT group). Potential risk factors of AMI including age, diabetes mellitus, hypertension, hyperlipidaemia, history of stroke, ischaemic heart disease, Eastern Cooperative Oncology Group Performance Status (ECOG PS) and duration of ADT were reviewed. The risk of AMI after ADT was first analysed using the Kaplan-Meier method, followed by Cox regression analyses including the potential risk factors mentioned. RESULTS: In all, 452 patients were included, with 200 patients in the non-ADT group and 252 patients in the ADT group. The mean (sd) age was 68.2 (5.9) years in the non-ADT group and 69.5 (6.5) years in the ADT group, and the difference was statistically significant (P = 0.031). There were no significant differences in their pre-existing medical conditions or ECOG PS. The ADT group was associated with an increased risk of AMI when compared with the non-ADT group (P = 0.004) upon Kaplan-Meier analysis. Upon multivariate Cox regression analysis, hyperlipidaemia, poor ECOG PS and the use of ADT were the only three significant factors that were associated with increased risk of developing new AMI. CONCLUSIONS: There was increased risk of AMI after ADT for prostate cancer in a Chinese population. Hyperlipidaemia and poor ECOG PS were also significant risk factors for developing AMI. The risk of AMI should be considered when deciding on ADT, especially in patients with history of hyperlipidaemia and relatively poor ECOG PS.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Infarto do Miocárdio/epidemiologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/epidemiologia , Idoso , China , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos
20.
Aging Male ; 18(3): 180-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26004988

RESUMO

We investigated the fracture risk after androgen deprivation therapy (ADT) for prostate cancer in the Chinese population. All Chinese prostate cancer patients who were treated primarily by radical prostatectomy or radiotherapy, with or without further ADT, from year 2000 to 2009 were reviewed. We compared the fracture risk in patients who were given ADT (ADT group) with those who were not given any ADT (non-ADT group). Potential risk factors including age, diabetes mellitus, hypertension, hyperlipidemia, ischemic heart disease and performance status were reviewed. The fracture risk was analyzed with Kaplan-Meier and multivariate Cox regression analyses. Our cohort consisted of 200 patients in the non-ADT group and 252 patients in the ADT group. The ADT group was shown to have higher fracture risk (p = 0.036) upon Kaplan-Meier analysis. Upon multivariate Cox regression analyses, diabetes mellitus (HR 4.39, 95% CI 1.08-17.83, p = 0.039), poor performance status (HR 3.14, 95% CI 1.24-8.00, p = 0.016) and the use of ADT (HR 4.89, 95% CI 1.03-23.17, p = 0.045) were associated with increased fracture risk. In conclusion, the fracture risk should be considered while deciding on ADT in Chinese men, especially in diabetic patients with poor performance status.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Complicações do Diabetes , Fraturas Ósseas/etiologia , Aptidão Física/fisiologia , Neoplasias da Próstata/tratamento farmacológico , Idoso , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Neoplasias da Próstata/complicações , Análise de Regressão , Estudos Retrospectivos , Medição de Risco , Fatores de Risco
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