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1.
Nature ; 617(7962): 717-723, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37225883

RESUMO

Flexible solar cells have a lot of market potential for application in photovoltaics integrated into buildings and wearable electronics because they are lightweight, shockproof and self-powered. Silicon solar cells have been successfully used in large power plants. However, despite the efforts made for more than 50 years, there has been no notable progress in the development of flexible silicon solar cells because of their rigidity1-4. Here we provide a strategy for fabricating large-scale, foldable silicon wafers and manufacturing flexible solar cells. A textured crystalline silicon wafer always starts to crack at the sharp channels between surface pyramids in the marginal region of the wafer. This fact enabled us to improve the flexibility of silicon wafers by blunting the pyramidal structure in the marginal regions. This edge-blunting technique enables commercial production of large-scale (>240 cm2), high-efficiency (>24%) silicon solar cells that can be rolled similarly to a sheet of paper. The cells retain 100% of their power conversion efficiency after 1,000 side-to-side bending cycles. After being assembled into large (>10,000 cm2) flexible modules, these cells retain 99.62% of their power after thermal cycling between -70 °C and 85 °C for 120 h. Furthermore, they retain 96.03% of their power after 20 min of exposure to air flow when attached to a soft gasbag, which models wind blowing during a violent storm.

2.
Prostate ; 83(7): 619-627, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36842160

RESUMO

BACKGROUND: Prostate cancer is addicted to androgens. The steroidogenic enzyme 3ß-hydroxysteroid dehydrogenase 1 (3ßHSD1) recognizes pregnenolone, dehydroepiandrosterone (DHEA), and steroidal medicine abiraterone as substrates to accelerate disease progression. METHODS: References for this review were identified through searches of PubMed with the search terms "prostate cancer", "HSD3B1", and "3bHSD1" from 1990 until June, 2022. RESULTS: Genotype of 3ßHSD1 has been reported to correlate with tumor aggressiveness of advanced prostate cancer in multiple clinical scenarios. The ethnic differences and limitations of using 3ßHSD1 genotype as a prognostic biomarker have been discussed here. The activity of 3ßHSD1 increases in patients treated with abiraterone and enzalutamide, giving rise to treatment resistance. Further elucidation of 3ßHSD1 regulatory mechanisms will shed light on more approaches for disease intervention. We also review the recent advance on 3ßHSD1 inhibitors and targeting 3ßHSD1 for prostate cancer management. Novel 3ßHSD1 inhibitors will be needed to provide additional options for prostate cancer management. CONCLUSION: 3ßHSD1 is both a predictive biomarker and a promising therapeutic target for prostate cancer.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Neoplasias da Próstata , Masculino , Humanos , Medicina de Precisão , Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Androgênios , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Nitrilas/uso terapêutico
3.
Neurol Sci ; 44(4): 1405-1409, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36781563

RESUMO

BACKGROUND: Paroxysmal kinesigenic dyskinesia (PKD) is a rare movement disorder with high clinical and genetic heterogeneity. Proline-rich transmembrane protein 2 (PRRT2) was identified as the first causative gene for PKD in 2011. Recently, heterozygous variants in transmembrane protein 151A (TMEM151A) were identified as another pathogenic cause of PKD. CASE DESCRIPTION: A 16-year-old man diagnosed with PKD exhibited hemidystonia triggered by sudden voluntary movements. His mother also had similar symptoms since the age of 20. Whole-exome sequencing revealed a likely pathogenic missense variant (c.892 T > C) in the TMEM151A gene. At the same time, we reviewed the literature focusing on the molecular characteristics and the clinical phenotypes in patients with TMEM151A variants, especially within the same family. CONCLUSION: This case further validated the pathogenic role of TMEM151A variants in PKD. The findings of interfamilial and intrafamilial variability in the phenotypes expanded our understanding of TMEM151A-related PKD.


Assuntos
Distonia , Humanos , Mutação , Distonia/genética , Distonia/diagnóstico , Mutação de Sentido Incorreto , Fenótipo
4.
Prostate ; 82(13): 1284-1292, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35747943

RESUMO

BACKGROUND: To investigate the prognostic value and potential therapeutic target of the baseline serum hormones in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone. METHODS: This retrospective study was performed in patients with mCRPC receiving abiraterone acetate (AA) from July 2016 to September 2020. Patients who had serum hormone tests within 2 weeks before AA treatment were included. Univariate analysis and Cox regression were performed to evaluate the correlation of sex hormones with progression-free survival (PFS) and overall survival (OS). Prolactin (PRL) expression in the clinical specimens was evaluated by immunohistochemistry. Bone metastases were quantified by automated Bone Scan Index (aBSI). RESULTS: The study included 61 patients with a median follow-up of 19.0 months. Patients with lower baseline PRL levels (median) responded better to AA than those with higher baseline PRL levels as indicated by prostate-specific antigen (PSA) reduction (PSA90, 66.7% vs. 25.8%, p = 0.001), PFS (19.6 vs. 7.9 months), and OS (52.8 vs. 19.2 months). Cox regression adjusted for clinical factors also confirmed that baseline PRL level was an independent predictive factor for PFS (hazard ratio = 1.096, p = 0.007). Prostatic PRL expression increased as the disease progressed. PRL expression was also detected in biopsy samples from bone metastasis but not in normal bone tissue, and the serum PRL levels were positively correlated with aBSIs (r = 0.28, p = 0.037). CONCLUSIONS: Serum PRL levels are predictive of response to AA in patients with mCRPC. Serum PRL levels are positively correlated with the volume of metastatic bone disease.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Acetato de Abiraterona/uso terapêutico , Androstenos/uso terapêutico , Humanos , Masculino , Prolactina/uso terapêutico , Antígeno Prostático Específico , Neoplasias de Próstata Resistentes à Castração/patologia , Estudos Retrospectivos , Resultado do Tratamento
5.
BMC Neurol ; 22(1): 45, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35123429

RESUMO

BACKGROUND: Varicella zoster virus (VZV) can remain lifelong in the latent state in ganglionic neurons and adrenal glands after the initial infection. However, it can be reactivated anytime and can trigger several severe neurological manifestations such as encephalitis, meningitis, Ramsay-Hunt syndrome, cerebellitis, myelitis, and stroke. In addition, due to the diversity of clinical manifestations, clinical diagnosis of VZV can be difficult, especially in the absence of varicella. Here, we describe the case of a 52-year-old male who presented with symptoms of acute myelitis as well as polycranial neuritis, and was finally diagnosed with VZV infection through metagenomic next-generation sequencing (mNGS). CASE PRESENTATION: A 52-year-old male came to our hospital with complaint of headache, fever, weakness of right lower limb, abdominal distension, and hearing loss. T2-weighted MRI revealed a hyperintense lesion in the spinal cord extending from T8 to T11. In addition, enhanced MRI showed small patches and strips hyperintensities in both the spinal cord and meninges. Plain abdominal radiographs and abdominal computed tomography (CT) scan displayed air-fluid levels and incomplete bowel obstruction. Moreover, electrophysiological evaluation of the peripheral neuropathy in the extremities was found to be normal. Finally, by using metagenomic next-generation sequencing (mNGS) we found that the copy number of VZV DNA in cerebrospinal fluid (CSF) was significantly increased and IgG antibody against VZV in CSF was also noted to be positive. Hence, VZV infection was identified in patient's central neuron system. Finally, after a few days of low dose steroid treatment, the patient's symptoms were found to be significantly improved. CONCLUSIONS: The findings indicate that we should pay proper attention to the various symptoms caused by VZV infection due to the clinical heterogeneity, especially in the absence of cutaneous lesions.


Assuntos
Herpes Zoster da Orelha Externa , Herpes Zoster , Mielite , Neurite (Inflamação) , Herpesvirus Humano 3/genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Mielite/diagnóstico por imagem
6.
BMC Neurol ; 22(1): 425, 2022 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-36376797

RESUMO

BACKGROUND: Spinal and bulbar muscular atrophy (SBMA) is an X-linked recessive hereditary neuromuscular disorder caused by the expanded trinucleotide repeat in the androgen receptors gene. The major clinical manifestations of SBMA consist of weakness in the bulbar and limb muscles, fasciculations, tremors, cramps, sensory impairment, and gynecomastia. However, atypical SBMA cases may lead to misdiagnosis. Muscular fatigue and decremental responses to repetitive nerve stimulation (RNS), despite being observed in some SBMA patients, are usually occurred in MG patients, and patient with the symptom of mastication fatigue was rarely reported. In addition, cardiological investigations have been performed in SBMA patients and several ECG alterations were identified. Here we report an SBMA patient presenting with a rare onset symptom of mastication fatigue, who has been detected with a positive titin antibody in the serum and showed a WPW pattern electrocardiogram. CASE PRESENTATION: The patient showed mildly progressive fatigue in the muscles of mastication over 3 years. Neurological examination showed facial muscle weakness and a wasting tongue with fasciculations, but the weakness, wasting, or fasciculations were not obvious in the limbs. 3-Hz RNS showed a decremental response in bilateral orbicularis oculi. The test of titin antibody was positive in the serum, and the electrocardiogram showed a WPW pattern ECG. Genetic analysis revealed an increased number (39 repeats) of tandem CAG repeats in the AR gene, which confirmed the diagnosis of SBMA. The fatigue symptom was significantly improved after oral pyridostigmine bromide treatment. CONCLUSION: This case calls for more attention to muscular fatigue as the onset symptoms of Kennedy's disease. ECG screening is of importance in SBMA patients and further studies are needed to investigate the titin antibody in SBMA patients as well as other neurogenic disorders.


Assuntos
Atrofia Bulboespinal Ligada ao X , Atrofia Muscular Espinal , Humanos , Masculino , Atrofia Bulboespinal Ligada ao X/complicações , Atrofia Bulboespinal Ligada ao X/diagnóstico , Atrofia Bulboespinal Ligada ao X/genética , Conectina/genética , Mastigação , Fasciculação , Fadiga
7.
Nature ; 533(7604): 547-51, 2016 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-27225130

RESUMO

Abiraterone blocks androgen synthesis and prolongs survival in patients with castration-resistant prostate cancer, which is otherwise driven by intratumoral androgen synthesis. Abiraterone is metabolized in patients to Δ(4)-abiraterone (D4A), which has even greater anti-tumour activity and is structurally similar to endogenous steroidal 5α-reductase substrates, such as testosterone. Here, we show that D4A is converted to at least three 5α-reduced and three 5ß-reduced metabolites in human serum. The initial 5α-reduced metabolite, 3-keto-5α-abiraterone, is present at higher concentrations than D4A in patients with prostate cancer taking abiraterone, and is an androgen receptor agonist, which promotes prostate cancer progression. In a clinical trial of abiraterone alone, followed by abiraterone plus dutasteride (a 5α-reductase inhibitor), 3-keto-5α-abiraterone and downstream metabolites were depleted by the addition of dutasteride, while D4A concentrations rose, showing that dutasteride effectively blocks production of a tumour-promoting metabolite and permits D4A accumulation. Furthermore, dutasteride did not deplete the three 5ß-reduced metabolites, which were also clinically detectable, demonstrating the specific biochemical effects of pharmacological 5α-reductase inhibition on abiraterone metabolism. Our findings suggest a previously unappreciated and biochemically specific method of clinically fine-tuning abiraterone metabolism to optimize therapy.


Assuntos
Inibidores de 5-alfa Redutase/farmacologia , Androgênios/biossíntese , Androstenos/metabolismo , Dutasterida/farmacologia , Dutasterida/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Inibidores de 5-alfa Redutase/uso terapêutico , Acetato de Abiraterona/administração & dosagem , Acetato de Abiraterona/sangue , Acetato de Abiraterona/metabolismo , Acetato de Abiraterona/uso terapêutico , Administração Oral , Antagonistas de Androgênios/farmacologia , Antagonistas de Androgênios/uso terapêutico , Androstenos/administração & dosagem , Androstenos/sangue , Androstenos/farmacologia , Animais , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Masculino , Camundongos , Oxirredução/efeitos dos fármacos , Neoplasias da Próstata/sangue , Neoplasias de Próstata Resistentes à Castração/sangue , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Nature ; 523(7560): 347-51, 2015 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-26030522

RESUMO

Prostate cancer resistance to castration occurs because tumours acquire the metabolic capability of converting precursor steroids to 5α-dihydrotestosterone (DHT), promoting signalling by the androgen receptor and the development of castration-resistant prostate cancer. Essential for resistance, DHT synthesis from adrenal precursor steroids or possibly from de novo synthesis from cholesterol commonly requires enzymatic reactions by 3ß-hydroxysteroid dehydrogenase (3ßHSD), steroid-5α-reductase (SRD5A) and 17ß-hydroxysteroid dehydrogenase (17ßHSD) isoenzymes. Abiraterone, a steroidal 17α-hydroxylase/17,20-lyase (CYP17A1) inhibitor, blocks this synthetic process and prolongs survival. We hypothesized that abiraterone is converted by an enzyme to the more active Δ(4)-abiraterone (D4A), which blocks multiple steroidogenic enzymes and antagonizes the androgen receptor, providing an additional explanation for abiraterone's clinical activity. Here we show that abiraterone is converted to D4A in mice and patients with prostate cancer. D4A inhibits CYP17A1, 3ßHSD and SRD5A, which are required for DHT synthesis. Furthermore, competitive androgen receptor antagonism by D4A is comparable to the potent antagonist enzalutamide. D4A also has more potent anti-tumour activity against xenograft tumours than abiraterone. Our findings suggest an additional explanation-conversion to a more active agent-for abiraterone's survival extension. We propose that direct treatment with D4A would be more clinically effective than abiraterone treatment.


Assuntos
Androstenos/metabolismo , Androstenos/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , 3-Hidroxiesteroide Desidrogenases/antagonistas & inibidores , 3-Hidroxiesteroide Desidrogenases/metabolismo , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , Inibidores de 5-alfa Redutase/metabolismo , Inibidores de 5-alfa Redutase/farmacologia , Inibidores de 5-alfa Redutase/uso terapêutico , Antagonistas de Receptores de Andrógenos/metabolismo , Antagonistas de Receptores de Andrógenos/farmacologia , Antagonistas de Receptores de Andrógenos/uso terapêutico , Androgênios/biossíntese , Androgênios/metabolismo , Androstenos/química , Androstenos/uso terapêutico , Animais , Benzamidas , Vias Biossintéticas/efeitos dos fármacos , Biotransformação , Divisão Celular , Cromatina/metabolismo , Di-Hidrotestosterona/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Nitrilas , Feniltioidantoína/análogos & derivados , Feniltioidantoína/farmacologia , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Receptores Androgênicos/metabolismo , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Esteroide 17-alfa-Hidroxilase/metabolismo , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Fish Physiol Biochem ; 46(2): 759-770, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31897859

RESUMO

The main purpose of this study was to evaluate the immunity, antioxidant indices, and disease resistance of quercetin in zebrafish (Danio rerio). A total of 630 fish were assigned to 21 tanks with 30 fish/tank, and they were exposed to 0, 0.01, 0.1, 1, 10, 100, and 1000 µg/L quercetin, respectively, for 56 days. Results indicated that the immune indices including acid phosphatase (ACP), myeloperoxidase (MPO), lysozyme activities, and Complement 3 (C3), C4, IgM contents were significantly higher in 1 µg/L quercetin group than these parameters in the control group (P < 0.05). TNF-α and IL-8 mRNA expressions significantly decreased as the levels of quercetin increased up to 1 µg/L and increased thereafter (P < 0.05). 1 and 10 µg/L quercetin groups showed significantly lower TNF-α and IL-8 mRNA levels than the quercetin-free group. Transforming growth factor-ß and IL-10 mRNA levels showed an obviously opposite trend with TNF-α expression. The SOD, GPX, CAT, T-AOC activities, and SOD and GPX gene expression in the liver were enhanced with increasing quercetin up to 1 µg/L, and decreased thereafter. MDA contents were affected by quercetin, in which 1 and 10 µg/L quercetin had a significantly lower level than that of the control group (P < 0.05). Defensin and Leap-II mRNA expression in the liver were the highest for fish exposed to 1 µg/L quercetin. The fish that exposed to 1 µg/L quercetin also showed a significantly higher survival rate than these of fish exposed to 0, 0.01, and 1000 µg/L quercetin (P < 0.05). In conclusion, the optimal level of quercetin promotes immunostimulant properties, antioxidant indices, and disease resistance of zebrafish.


Assuntos
Quercetina , Peixe-Zebra/fisiologia , Ração Animal , Animais , Antioxidantes/metabolismo , Suplementos Nutricionais , Resistência à Doença , Interleucina-10 , Peixe-Zebra/imunologia
10.
J Biol Chem ; 293(46): 17829-17837, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30262668

RESUMO

Androgens such as testosterone and dihydrotestosterone are a critical driver of prostate cancer progression. Cancer resistance to androgen deprivation therapies ensues when tumors engage metabolic processes that produce sustained androgen levels in the tissue. However, the molecular mechanisms involved in this resistance process are unclear, and functional imaging modalities that predict impending resistance are lacking. Here, using the human LNCaP and C4-2 cell line models of prostate cancer, we show that castration treatment-sensitive prostate cancer cells that normally have an intact glucuronidation pathway that rapidly conjugates and inactivates dihydrotestosterone and thereby limits androgen signaling, become glucuronidation deficient and resistant to androgen deprivation. Mechanistically, using CRISPR/Cas9-mediated gene ablation, we found that loss of UDP glucuronosyltransferase family 2 member B15 (UGT2B15) and UGT2B17 is sufficient to restore free dihydrotestosterone, sustained androgen signaling, and development of castration resistance. Furthermore, loss of glucuronidation enzymatic activity was also detectable with a nonsteroid glucuronidation substrate. Of note, glucuronidation-incompetent cells and the resultant loss of intracellular conjugated dihydrotestosterone were detectable in vivo by 18F-dihydrotestosterone PET. Together, these findings couple a mechanism with a functional imaging modality to identify impending castration resistance in prostate cancers.


Assuntos
Di-Hidrotestosterona/metabolismo , Neoplasias de Próstata Resistentes à Castração/diagnóstico por imagem , Neoplasias de Próstata Resistentes à Castração/metabolismo , Testosterona/metabolismo , Animais , Linhagem Celular Tumoral , Di-Hidrotestosterona/química , Radioisótopos de Flúor , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Glicosilação , Humanos , Masculino , Camundongos , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/metabolismo , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos/química , Receptores Androgênicos/fisiologia , Transdução de Sinais , Testosterona/química
11.
J Cell Biochem ; 120(11): 18862-18870, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31264250

RESUMO

Oxidized low-density lipoprotein (ox-LDL)-induced endothelial injury plays crucial roles in the development of arteriosclerosis (AS). Golgi apparatus (GA) fragmentation is involved in various pathological processes, including endothelial injury. However, the role of GA fragmentation in ox-LDL-induced endothelial injury has not been determined. In this study, human umbilical vein endothelial cells (HUVECs) subjected to ox-LDL were used as an in vitro AS model. Herein, we showed that ox-LDL restrained proliferation and induced apoptosis and GA fragmentation of HUVECs. Moreover, overexpression of GRASP65 significantly prevented ox-LDL-induced GA fragmentation and endothelial cell injury by enhancing cell viability, nitric oxide production, and endothelial NOS expression and reducing apoptosis. Mechanistically, ox-LDL resulted in the activation of the extracellular signal-regulated kinase (ERK) pathway in HUVECs. Inactivation of the ERK pathway by U0126 suppressed the phosphorylation of GRASP65, GA fragmentation, and endothelial cell injury induced by ox-LDL. In conclusion, ox-LDL triggers GA fragmentation in HUVECs via activating the ERK signaling pathway, which participates in endothelial injury during the development of AS.


Assuntos
Arteriosclerose , Complexo de Golgi , Lipoproteínas LDL/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Arteriosclerose/metabolismo , Arteriosclerose/patologia , Complexo de Golgi/metabolismo , Complexo de Golgi/patologia , Proteínas da Matriz do Complexo de Golgi/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Lipoproteínas LDL/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
12.
Opt Express ; 27(14): 19212-19217, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503684

RESUMO

Dielectric metasurfaces provide the new freedom to implement information encoding and image hiding with monolayer of artificial atoms instead of bulky optical components to enable wavelength, phase and polarization modulations. We proposed an optical encryption scheme by integrating the Visual Cyptography (VC) with the phase-encoding technique for metasurface. In the encryption process, the secret image is hidden into a group of unrecognizable and mutually-unrelated phase-only meta-holograms with high security of concealment. In the decryption process, the secret image is extracted conveniently by superimposing the reconstructed holographic patterns via directly illuminating the generated meta-holograms instead of complicated holographic exposure facilities and additional cryptographic computations. Different from the general polarization or wavelength encryption of meta-hologram, we use VC to share the secret image into a set of encrypted meta-holograms for the first time, which greatly improves the security of image hiding. In view of the merits of high security, simple decryption and flexible adjustability, we believe it will have significant potential applications in the future optical information security.

13.
IUBMB Life ; 70(5): 432-436, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29637686

RESUMO

Multiple sclerosis (MS) is a poorly understood disease mechanistically. MOG35-55 peptide induced experimental autoimmune encephalomyelitis (EAE) is a broadly used model to study MS. Using this model we have earlier shown that the antioxidant tempol or the small molecule inhibitor of p38 SB203580 can effectively prevent EAE progression. This effect was mediated by means of regulating immune inflammation, signaling by the p38MAPK-SGK1 pathway, and oxidative stress. However, there is a need to test drugs that can be used in pharmacological intervention of EAE. Given that nordihydroguaiaretic Acid (NDGA) has been shown to possess anti-oxidant activity and capacity of antagonizing autoimmune inflammation, we tested the effect of NDGA in ameliorating EAE in the current study. NDGA showed significant beneficial effect against EAE with both anti-inflammation and antioxidant activity. NDGA could weaken the immune inflammation at least partly by inhibiting the oxidant stress-p38MAPK-SGK1 pathway representing a target for putative pharmacological intervention. © 2018 IUBMB Life, 70(5):432-436, 2018.


Assuntos
Doenças Desmielinizantes/tratamento farmacológico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Fatores Imunológicos/farmacologia , Masoprocol/farmacologia , Fármacos Neuroprotetores/farmacologia , Animais , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/genética , Doenças Desmielinizantes/imunologia , Progressão da Doença , Encefalomielite Autoimune Experimental/induzido quimicamente , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Feminino , Regulação da Expressão Gênica , Heme Oxigenase-1/genética , Heme Oxigenase-1/metabolismo , Proteínas Imediatamente Precoces/antagonistas & inibidores , Proteínas Imediatamente Precoces/genética , Proteínas Imediatamente Precoces/metabolismo , Injeções Intraperitoneais , Camundongos , Camundongos Endogâmicos C57BL , Glicoproteína Mielina-Oligodendrócito , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Fragmentos de Peptídeos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
14.
Opt Express ; 25(25): 31509-31515, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29245825

RESUMO

As interferometry is the highest precision distance measuring technique, we proposed a mechanism of single-beam interferometry employing all-dielectric photonic metamaterial with effective zero-index as a means of precise displacement measurement. This mechanism offers a straightforward method for performing optical range-finding over multi-wavelength and sub-wavelength displacements in a compact uniaxial reflection configuration. The higher sensitivity and resolution can be achieved in this mechanism with the intrinsic accuracy of λ/4. The predesignated measuring device based on the proposed strategy could be directly scaled in dimensions to work at different frequency regions without the need for reconfiguration. Both numerical simulations and experiment have demonstrated its feasibilities and reliability. We believe it will have significant potential applications in the future optical measurement.

15.
Proc Natl Acad Sci U S A ; 108(8): 3116-23, 2011 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-21282610

RESUMO

Histone methylation has an important role in transcriptional regulation. However, unlike H3K4 and H3K9 methylation, the role of H4K20 monomethylation (H4K20me-1) in transcriptional regulation remains unclear. Here, we show that Wnt3a specifically stimulates H4K20 monomethylation at the T cell factor (TCF)-binding element through the histone methylase SET8. Additionally, SET8 is crucial for activation of the Wnt reporter gene and target genes in both mammalian cells and zebrafish. Furthermore, SET8 interacts with lymphoid enhancing factor-1 (LEF1)/TCF4 directly, and this interaction is regulated by Wnt3a. Therefore, we conclude that SET8 is a Wnt signaling mediator and is recruited by LEF1/TCF4 to regulate the transcription of Wnt-activated genes, possibly through H4K20 monomethylation at the target gene promoters. Our findings also indicate that H4K20me-1 is a marker for gene transcription activation, at least in canonical Wnt signaling.


Assuntos
Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Ativação Transcricional , Proteínas Wnt/genética , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Biomarcadores , Fator 1 de Ligação ao Facilitador Linfoide/metabolismo , Lisina/metabolismo , Mamíferos , Metilação , Transdução de Sinais/genética , Fator de Transcrição 4 , Fatores de Transcrição/metabolismo , Proteína Wnt3 , Proteína Wnt3A , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
16.
Proc Natl Acad Sci U S A ; 108(29): 12119-24, 2011 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-21730158

RESUMO

Proliferation of the neural/neuronal progenitor cells (NPCs) at the ventricular zone of the dorsal spinal cord requires the stimuli of Wnt and bone morphogenic protein (BMP). However, how these two signaling pathways are regulated to initiate differentiation in the NPCs as they enter the intermediate zone is not known. Here, we show that Smad6, a negative regulator of BMP signaling, is expressed in the intermediate zone of the chick dorsal spinal cord. Knockdown experiments show that Smad6 is required for promoting NPCs to exit the cell cycle and differentiate into neurons. Although we find that Smad6 inhibits BMP signaling, as expected, we also find that Smad6 unexpectedly inhibits the Wnt/ß-catenin pathway. The inhibition of the Wnt/ß-catenin pathway by Smad6 is independent of its effect on the BMP pathway. Rather, Smad6 through its N-terminal domain and link region enhances the interaction of C-terminal binding protein with the ß-catenin/T cell factor (TCF) complex and the TCF-binding element to inhibit ß-catenin-mediated transcriptional activation. Our study provides evidence that transition of NPCs from a proliferative state to a differentiating state is controlled by the dual inhibitory role of Smad6 to both BMP and Wnt signaling at the level of transcription.


Assuntos
Diferenciação Celular/fisiologia , Regulação da Expressão Gênica/fisiologia , Tubo Neural/embriologia , Neurônios/citologia , Transdução de Sinais/fisiologia , Proteína Smad6/metabolismo , Análise de Variância , Animais , Western Blotting , Bromodesoxiuridina , Embrião de Galinha , Imunoprecipitação da Cromatina , Primers do DNA/genética , Eletroporação , Imunofluorescência , Regulação da Expressão Gênica/genética , Imunoprecipitação , Hibridização In Situ , Luciferases , Tubo Neural/metabolismo , Reação em Cadeia da Polimerase , Interferência de RNA , Proteína Smad6/genética , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
17.
J Hazard Mater ; 474: 134787, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38823101

RESUMO

The developmental toxicity effects of neonicotinoid pesticides such as clothianidin have not been fully explored in agricultural applications. This is particularly noteworthy because such pesticides significantly impact the survival rates of invertebrates, with arthropod larvae being particularly vulnerable. This study aimed to address this research gap by specifically investigating the toxicological effects of clothianidin on the developmental stages of the larvae of the economically important aquaculture species Penaeus vannamei. In these experiments, shrimp eggs were exposed to seawater containing different concentrations of clothianidin beginning at N1, and each phase was observed and analyzed to determine its toxic impact on larval development. These results revealed that clothianidin induces an increase in deformity rates and triggers abnormal cell apoptosis. It also significantly reduced survival rates and markedly decreased body length and heart rate in the later stages of larval development (P3). Transcriptomic analysis revealed disruptions in larval DNA integrity, protein synthesis, and signal transduction caused by clothianidin. To survive prolonged exposure, larvae may attempt to maintain their viability by repairing cell structures and enhancing signal transduction mechanisms. This study offers the first empirical evidence of the toxicity of clothianidin to arthropod larvae, underscoring the impact of environmental pollution on aquatic health.


Assuntos
Guanidinas , Inseticidas , Larva , Neonicotinoides , Penaeidae , Tiazóis , Animais , Larva/efeitos dos fármacos , Neonicotinoides/toxicidade , Guanidinas/toxicidade , Tiazóis/toxicidade , Inseticidas/toxicidade , Penaeidae/efeitos dos fármacos , Penaeidae/crescimento & desenvolvimento , Poluentes Químicos da Água/toxicidade , Apoptose/efeitos dos fármacos
18.
Chemosphere ; 358: 142150, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38679174

RESUMO

Cycloxaprid, a new neonicotinoid pesticide, poses ecological risks, particularly in aquatic environments, due to its unique action and environmental dispersal. This study investigated the ecotoxicological effects of various concentrations of cycloxaprid on Penaeus vannamei over 28 days. High cycloxaprid levels significantly altered shrimp physiology, as shown by changes in the hepatosomatic index and fattening. Indicators of oxidative stress, such as increased serum hemocyanin, respiratory burst, and nitric oxide, as well as decreased phenol oxidase activity, were observed. Additionally, elevated activities of lactate dehydrogenase, succinate dehydrogenase, and isocitrate dehydrogenase indicated disrupted energy metabolism in the hepatopancreas. Notably, analyses of the nervous system revealed marked disturbances in neural signaling, as evidenced by elevated acetylcholine, octopamine, and acetylcholinesterase levels. Transcriptomic analysis highlighted significant effects on gene expression and metabolic processes in the hepatopancreas and nervous system. This study demonstrated that cycloxaprid disrupts neural signaling and oxidative balance in P. vannamei, potentially affecting its growth, and provides key insights into its biochemical and transcriptomic toxicity in aquatic systems.


Assuntos
Penaeidae , Poluentes Químicos da Água , Animais , Poluentes Químicos da Água/toxicidade , Penaeidae/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Neonicotinoides/toxicidade , Piridinas/toxicidade , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/metabolismo , Inseticidas/toxicidade , Compostos Heterocíclicos com 3 Anéis
19.
ACS Omega ; 9(31): 33437-33447, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39130580

RESUMO

Coal and gas outburst is the mechanical damage behavior of gas-containing coal in a complex environment. In this paper, the established experimental system is used to carry out hammer damage experiments on coal adsorption of different gases under different gas pressures and analyze the mass distribution and surface area distribution characteristics of coal samples in each particle size interval after the hammer damage of coal samples. The energy of the crushing process was analyzed by using the specific work of crushing, mass of newly generated particle size added per unit of energy, newly added surface area per unit of energy, and newly added specific surface area per unit of energy. The results show that the crushing effect of gas-containing coal samples during hammer damage is related to the type and pressure of the adsorbed gas. The stronger the gas adsorption performance and the higher the gas pressure, the weaker the effect of gas-containing coal hammer damage. Meanwhile, the energy required for the mass and surface area of coal samples with newly generated particle size decreased, indicating that the stronger the gas adsorption and the higher the gas pressure, the more serious the energy dissipation in the hammering damage process of gas-containing coal samples. The research results are conducive to an in-depth understanding of the coal and gas outburst processes, which can provide a theoretical basis for the damage characteristics and energy dissipation of coal and gas outbursts.

20.
J Hazard Mater ; 469: 133930, 2024 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-38452673

RESUMO

Dinotefuran, a neonicotinoid insecticide, may impact nontarget organisms such as Decapoda P. vannamei shrimp with nervous systems similar to insects. Exposing shrimp to low dinotefuran concentrations (6, 60, and 600 µg/L) for 21 days affected growth, hepatosomatic index, and survival. Biomarkers erythromycin-N-demethylase, alanine aminotransferase, and catalase increased in all exposed groups, while glutathione S-transferase is the opposite; aminopyrin-N-demethylase, malondialdehyde, and aspartate aminotransferase increased at 60 and 600 µg/L. Concentration-dependent effects on gut microbiota altered the abundance of bacterial groups, increased potentially pathogenic and oxidative stress-resistant phenotypes, and decreased biofilm formation. Gram-positive/negative microbiota changed significantly. Metabolite differences between the exposed and control groups were identified using mass spectrometry and KEGG pathway enrichment. N-acetylcystathionine showed potential as a reliable dinotefuran metabolic marker. Weighted correlation network analysis (WGCNA) results indicated high connectivity of cruecdysone in the metabolite network and significant enrichment at 600 µg/L dinotefuran. The WGCNA results revealed a highly significant negative correlation between two key metabolites, caldine and indican, and the gut microbiota within co-expression modules. Overall, the risk of dinotefuran exposure to non-target organisms in aquatic environments still requires further attention.


Assuntos
Microbioma Gastrointestinal , Guanidinas , Nitrocompostos , Penaeidae , Animais , Penaeidae/genética , Penaeidae/metabolismo , Penaeidae/microbiologia , Neonicotinoides/toxicidade , Neonicotinoides/metabolismo , Oxirredutases N-Desmetilantes/metabolismo , Oxirredutases N-Desmetilantes/farmacologia
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