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1.
FASEB J ; 36(1): e22075, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34919285

RESUMO

Long non-coding RNAs (lncRNAs) regulate neurological damage in cerebral ischemia-reperfusion injury (CIRI). This study aimed to investigate the biological roles of lncRNA CEBPA-AS1 in CIRI. Middle cerebral artery occlusion and ischemia-reperfusion injury (MCAO/IR) rat model and oxygen-glucose deprivation and reoxygenation (OGD/R) cell lines were generated; the expression of CEBPA-AS1 was evaluated by qRT-PCR. The effects of CEBPA-AS1 on cell apoptosis and nerve damage were examined. The downstream microRNA (miRNA) and mRNA of CEBPA-AS1 were predicted and verified. We found that overexpression of CEBPA-AS1 could attenuate MCAO/IR-induced nerve damage and neuronal apoptosis in the rat model. Knockdown of CEBPA-AS1 aggravated cell apoptosis and enhanced the production of LDH and MDA in the OGD/R cells. Upon examining the molecular mechanisms, we found that CEBPA-AS1 stimulated APPL1 expression by combining with miR-340-5p, thereby regulating the APPL1/LKB1/AMPK pathway. In the rescue experiments, CEBPA-AS1 overexpression was found to attenuate OGD/R-induced cell apoptosis and MCAO/IR induced nerve damage, while miR-340-5p reversed these effects of CEBPA-AS1. In conclusion, CEBPA-AS1 could decrease CIRI by sponging miR-340-5, regulating the APPL1/LKB1/AMPK pathway.


Assuntos
Quinases Proteína-Quinases Ativadas por AMP/biossíntese , Proteínas Quinases Ativadas por AMP/biossíntese , Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Transtornos Cerebrovasculares/metabolismo , MicroRNAs/biossíntese , Proteínas do Tecido Nervoso/biossíntese , RNA Longo não Codificante/biossíntese , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais , Quinases Proteína-Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Apoptose , Transtornos Cerebrovasculares/genética , Transtornos Cerebrovasculares/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica , MicroRNAs/genética , Proteínas do Tecido Nervoso/genética , RNA Longo não Codificante/genética , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/patologia
2.
Eur Radiol ; 33(12): 9109-9119, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37438642

RESUMO

OBJECTIVES: Using diffusion basis spectrum imaging (DBSI) to examine the microstructural changes in the substantia nigra (SN) and global white matter (WM) tracts of patients with early-stage PD. METHODS: Thirty-seven age- and sex-matched patients with early-stage PD and 22 healthy controls (HCs) were enrolled in this study. All participants underwent clinical assessments and diffusion-weighted MRI scans, analyzed by diffusion tensor imaging (DTI) and DBSI to assess the pathologies of PD in SN and global WM tracts. RESULTS: The lower DTI fraction anisotropy (FA) was seen in SN of PD patients (PD: 0.316 ± 0.034 vs HCs: 0.331 ± 0.019, p = 0.015). The putative cells marker-DBSI-restricted fraction (PD: 0.132 ± 0.051 vs HCs: 0.105 ± 0.039, p = 0.031) and the edema/extracellular space marker-DBSI non-restricted-fraction (PD: 0.150 ± 0.052 vs HCs: 0.122 ± 0.052, p = 0.020) were both significantly higher and the density of axons/dendrites marker-DBSI fiber-fraction (PD: 0.718 ± 0.073 vs HCs: 0.773 ± 0.071, p = 0.003) was significantly lower in SN of PD patients. DBSI-restricted fraction in SN was negatively correlated with HAMA scores (r = - 0.501, p = 0.005), whereas DTI-FA was not correlated with any clinical scales. In WM tracts, only higher DTI axial diffusivity (AD) among DTI metrics was found in multiple WM regions in PD, while lower DBSI fiber-fraction and higher DBSI non-restricted-fraction were detected in multiple WM regions. DBSI non-restricted-fraction in both left fornix (cres)/stria terminalis (r = -0.472, p = 0.004) and right posterior thalamic radiation (r = - 0.467, p = 0.005) was negatively correlated with MMSE scores. CONCLUSION: DBSI could potentially detect and quantify the extent of inflammatory cell infiltration, fiber/dendrite loss, and edema in both SN and WM tracts in patients with early-stage PD, a finding remains to be further investigated through more extensive longitudinal DBSI analysis. CLINICAL RELEVANCE STATEMENT: Our study shows that DBSI indexes can potentially detect early-stage PD's pathological changes, with a notable ability to distinguish between inflammation and edema. This implies that DBSI has the potential to be an imaging biomarker for early PD diagnosis. KEY POINTS: • Diffusion basis spectrum imaging detected higher restricted-fraction in Parkinson's disease, potentially reflecting inflammatory cell infiltration. • Diffusion basis spectrum imaging detected higher non-restricted-fraction and lower fiber-fraction in Parkinson's disease, indicating the presence of edema and/or dopaminergic neuronal/dendritic loss. • Diffusion basis spectrum imaging metrics correlated with non-motor symptoms, suggesting its potential diagnostic role to detect early-stage PD dysfunctions.


Assuntos
Doença de Parkinson , Substância Branca , Humanos , Imagem de Tensor de Difusão/métodos , Substância Branca/patologia , Doença de Parkinson/patologia , Substância Negra/diagnóstico por imagem , Substância Negra/patologia , Edema/patologia
3.
J Org Chem ; 88(5): 2832-2840, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36791405

RESUMO

A commercially available and versatile dehydrative amidation catalyst, featuring a thianthrene boron acid structure, has been developed. The catalyst shows high catalytic activity to both aliphatic and less reactive aromatic carboxylic acid substrates, including several bioactive or clinical molecules with a carboxylic acid group.

4.
Neurosurg Rev ; 46(1): 64, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36877325

RESUMO

To explore the utility of transcranial Doppler (TCD) findings when assessing bypass patency in patients with Moyamoya disease (MMD). Computed tomography angiography (CTA) and TCD sonography (TCDS) were performed before and after surgery to evaluate bypass patency. The peak systolic flow velocity (PSV) of the superficial temporal artery (STA) and the pulsatility index (PI) were compared between the groups that achieved patency and not, and receiver operating characteristic (ROC) curve analyses were used to define the TCDS criteria revealing patency. This study included 35 hemispheres (15 women; mean age 47 years) with Moyamoya disease who underwent STA-middle carotid artery bypass in our institution between January 2022 and October 2022. The PSV first increased on postoperative days 4-5 and then decreased on postoperative days 6-7 and 7-8. Patients with transient neurological diseases (TNDs), compared to those without, evidenced a significantly lower PSV value (P < 0.05). Compared with the non-patency group, the PSV was higher (P < 0.001) in the patency group. The cutoff values reflecting patency with good sensitivity and specificity were PSV > 49.00; PSV ratio (postoperative/preoperative) > 1.218; PSV ratio (operation side/contralateral side) > 1.082; and PSV ratio (adjusted) > 1.202. In the patency group, the PSV and PI significantly increased (P < 0.001) and decreased (P < 0.001) respectively. Bypass patency can be noninvasively and accurately evaluated via TCDS, affording an objective basis for assessment of the effect of revascularization surgery on patients with MMD.


Assuntos
Angiografia por Tomografia Computadorizada , Doença de Moyamoya , Humanos , Feminino , Pessoa de Meia-Idade , Doença de Moyamoya/diagnóstico por imagem , Doença de Moyamoya/cirurgia , Ultrassonografia Doppler Transcraniana , Angiografia
5.
BMC Musculoskelet Disord ; 24(1): 384, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37189083

RESUMO

BACKGROUND: Masquelet's induced membrane (IM) has osteogenesis activity, but IM spontaneous osteogenesis (SO) has not been described previously. OBJECTIVES: To report on varying degrees of IMSO and analyze its possible causes. METHODS: Twelve eight-week-old male Sprague-Dawley rats with 10 mm right femoral bone defects who received the first stage of IM technique (IMT) were used to observe the SO. In addition, clinical data from patients with bone defects who received the first stage of IMT with an interval of > 2 months post-operatively and exhibited SO between January 2012 and June 2020 were retrospectively analyzed. The SO was divided into four grades according to the amount and characteristics of the new bone formation. RESULTS: At twelve weeks, grade II SO was observed in all rats, and more new bone was formed in the IM near the bone end forming an uneven margin. Histology revealed bone and cartilage foci in the new bone. Four of the 98 patients treated with the first stage of IMT exhibited IMSO, including one female and three males with a median age of 40.5 years (range 29-52 years). The bone defects were caused by severe fractures and infection in two cases and by infection or tumor in one case each. Partial or segmental defects occurred in two cases. The time interval between inserting a cement spacer and diagnosis of SO ranged from six months to nine years. Two cases were grade I, and one case each of grades III and IV. CONCLUSION: Varying degrees of SO confirm the existence of the IMSO phenomenon. Bioactive bone tissue or local inflammation and a long time interval are the primary reasons underlying enhancement of the osteogenic activity of IM and leading to SO, which tends to take place as endochondral osteogenesis.


Assuntos
Fraturas Ósseas , Osteogênese , Ratos , Masculino , Feminino , Animais , Ratos Sprague-Dawley , Estudos Retrospectivos , Fêmur/diagnóstico por imagem , Fêmur/cirurgia
6.
Neurosurg Focus ; 55(3): E7, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37657107

RESUMO

OBJECTIVE: Diffusion basis spectrum imaging (DBSI) has shown promise in evaluating cervical spinal cord structural changes in patients with cervical spondylotic myelopathy (CSM). DBSI may also be valuable in the postoperative setting by serially tracking spinal cord microstructural changes following decompressive cervical spine surgery. Currently, there is a paucity of studies investigating this topic, likely because of challenges in resolving signal distortions from spinal instrumentation. Therefore, the objective of this study was to assess the feasibility of DBSI metrics extracted from the C3 spinal level to evaluate CSM patients postoperatively. METHODS: Fifty CSM patients and 20 healthy controls were enrolled in a single-center prospective study between 2018 and 2020. All patients and healthy controls underwent preoperative and postoperative diffusion-weighted MRI (dMRI) at a 2-year follow-up. All CSM patients underwent decompressive cervical surgery. The modified Japanese Orthopaedic Association (mJOA) score was used to categorize CSM patients as having mild, moderate, or severe myelopathy. DBSI metrics were extracted from the C3 spinal cord level to minimize image artifact and reduce partial volume effects. DBSI anisotropic tensors evaluated white matter tracts through fractional anisotropy, axial diffusivity, radial diffusivity, and fiber fraction. DBSI isotropic tensors assessed extra-axonal pathology through restricted and nonrestricted fractions. RESULTS: Of the 50 CSM patients, both baseline and postoperative dMR images with sufficient quality for analysis were obtained in 27 patients. These included 15 patients with mild CSM (mJOA scores 15-17), 7 with moderate CSM (scores 12-14), and 5 with severe CSM (scores 0-11), who were followed up for a mean of 23.5 (SD 4.1, range 11-31) months. All preoperative C3-level DBSI measures were significantly different between CSM patients and healthy controls (p < 0.05), except DBSI fractional anisotropy (p = 0.31). At the 2-year follow-up, the same significance pattern was found between CSM patients and healthy controls, except DBSI radial diffusivity was no longer statistically significant (p = 0.75). When assessing change (i.e., postoperative - preoperative values) in C3-level DBSI measures, CSM patients exhibited significant decreases in DBSI radial diffusivity (p = 0.02), suggesting improvement in myelin integrity (i.e., remyelination) at the 2-year follow-up. Among healthy controls, there was no significant difference in DBSI metrics over time. CONCLUSIONS: DBSI metrics derived from dMRI at the C3 spinal level can be used to provide meaningful insights into representations of the spinal cord microstructure of CSM patients at baseline and 2-year follow-up. DBSI may have the potential to characterize white matter tract recovery and inform outcomes following decompressive cervical surgery for CSM.


Assuntos
Doenças da Medula Espinal , Humanos , Estudos de Viabilidade , Estudos Prospectivos , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia
7.
Ecotoxicol Environ Saf ; 266: 115550, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37832486

RESUMO

Microglia-mediated chronic neuroinflammation has been associated with cognitive decline induced by rotenone, a well-known neurotoxic pesticide used in agriculture. However, the mechanisms remain unclear. This work aimed to elucidate the role of complement receptor 3 (CR3), a highly expressed receptor in microglia, in cognitive deficits induced by rotenone. Rotenone up-regulated the expression of CR3 in the hippocampus and cortex area of mice. CR3 deficiency markedly ameliorated rotenone-induced cognitive impairments, neurodegeneration and phosphorylation (Ser129) of α-synuclein in mice. CR3 deficiency also attenuated rotenone-stimulated microglial M1 activation. In microglial cells, siRNA-mediated knockdown of CR3 impeded, while CR3 activation induced by LL-37 exacerbated, rotenone-induced microglial M1 activation. Mechanistically, CR3 deficiency blocked rotenone-induced activation of nuclear factor κB (NF-κB), signal transducer and activator of transcription 1 (STAT1) and STAT3 signaling pathways. Pharmacological inhibition of NF-κB or STAT3 but not STAT1 was confirmed to suppress microglial M1 activation elicited by rotenone. Further study revealed that CR3 deficiency or knockdown also reduced rotenone-induced expression of C3, an A1 astrocyte marker, and production of microglial C1q, TNFα and IL-1α, a cocktail for activated microglia to induce neurotoxic A1 astrocytes, via NF-κB and STAT3 pathways. Finally, a small molecule modulator of CR3 efficiently mitigated rotenone-elicited cognitive deficits in mice even administered after the establishment of cognitive dysfunction. Taken together, our findings demonstrated that CR3 is a key factor in mediating neurotoxic glial activation and subsequent cognitive impairments in rotenone-treated mice, giving novel insights into the immunopathogenesis of cognitive impairments in pesticide-related Parkinsonism.


Assuntos
Disfunção Cognitiva , Praguicidas , Camundongos , Animais , NF-kappa B/genética , NF-kappa B/metabolismo , Rotenona/toxicidade , Disfunção Cognitiva/induzido quimicamente , Receptores de Complemento
8.
Mult Scler ; 28(3): 418-428, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34132126

RESUMO

BACKGROUND: Advanced magnetic resonance imaging (MRI) methods can provide more specific information about various microstructural tissue changes in multiple sclerosis (MS) brain. Quantitative measurement of T1 and T2 relaxation, and diffusion basis spectrum imaging (DBSI) yield metrics related to the pathology of neuroinflammation and neurodegeneration that occurs across the spectrum of MS. OBJECTIVE: To use relaxation and DBSI MRI metrics to describe measures of neuroinflammation, myelin and axons in different MS subtypes. METHODS: 103 participants (20 clinically isolated syndrome (CIS), 33 relapsing-remitting MS (RRMS), 30 secondary progressive MS and 20 primary progressive MS) underwent quantitative T1, T2, DBSI and conventional 3T MRI. Whole brain, normal-appearing white matter, lesion and corpus callosum MRI metrics were compared across MS subtypes. RESULTS: A gradation of MRI metric values was seen from CIS to RRMS to progressive MS. RRMS demonstrated large oedema-related differences, while progressive MS had the most extensive abnormalities in myelin and axonal measures. CONCLUSION: Relaxation and DBSI-derived MRI measures show differences between MS subtypes related to the severity and composition of underlying tissue damage. RRMS showed oedema, demyelination and axonal loss compared with CIS. Progressive MS had even more evidence of increased oedema, demyelination and axonal loss compared with CIS and RRMS.


Assuntos
Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Substância Branca , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Imageamento por Ressonância Magnética , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Esclerose Múltipla Crônica Progressiva/diagnóstico por imagem , Esclerose Múltipla Crônica Progressiva/patologia , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/patologia , Doenças Neuroinflamatórias , Substância Branca/diagnóstico por imagem , Substância Branca/patologia
9.
Nanotechnology ; 34(2)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36219884

RESUMO

In this study, the homojunction thin-film transistors (TFTs) with amorphous indium gallium zinc oxide (a-IGZO) as active channel layers and source/drain electrodes were fabricated by RF magnetron sputtering. The effect of oxygen partial pressure on the phase, microstructure, optical and electrical properties of IGZO thin films was investigated. The results showed that amorphous IGZO thin films always exhibit a high transmittance above 90% and wide band gaps of around 3.9 eV. The resistivity increases as the IGZO thin films are deposited at a higher oxygen partial pressure due to the depletion of oxygen vacancies. In addition, the electrical behaviors in homojunction IGZO TFTs were analyzed. When the active channel layers were deposited with an oxygen partial pressure of 1.96%, the homojunction IGZO TFTs exhibited optimal transfer and output characteristics with a field-effect mobility of 13.68 cm2V-1s-1. Its sub-threshold swing, threshold voltage and on/off ratio are 0.6 V/decade, 0.61 V and 107, respectively.

10.
Brain ; 144(1): 213-223, 2021 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-33253366

RESUMO

The aim of this study was to determine the feasibility of diffusion basis spectrum imaging in multiple sclerosis at 7 T and to investigate the pathological substrates of tissue damage in lesions and normal-appearing white matter. To this end, 43 patients with multiple sclerosis (24 relapsing-remitting, 19 progressive), and 21 healthy control subjects were enrolled. White matter lesions were classified in T1-isointense, T1-hypointense and black holes. Mean values of diffusion basis spectrum imaging metrics (fibres, restricted and non-restricted fractions, axial and radial diffusivities and fractional anisotropy) were measured from whole brain white matter lesions and from both lesions and normal appearing white matter of the corpus callosum. Significant differences were found between T1-isointense and black holes (P ranging from 0.005 to <0.001) and between lesions' centre and rim (P < 0.001) for all the metrics. When comparing the three subject groups in terms of metrics derived from corpus callosum normal appearing white matter and T2-hyperintense lesions, a significant difference was found between healthy controls and relapsing-remitting patients for all metrics except restricted fraction and fractional anisotropy; between healthy controls and progressive patients for all metrics except restricted fraction and between relapsing-remitting and progressive multiple sclerosis patients for all metrics except fibres and restricted fractions (P ranging from 0.05 to <0.001 for all). Significant associations were found between corpus callosum normal-appearing white matter fibres fraction/non-restricted fraction and the Symbol Digit Modality Test (respectively, r = 0.35, P = 0.043; r = -0.35, P = 0.046), and between black holes radial diffusivity and Expanded Disability Status Score (r = 0.59, P = 0.002). We showed the feasibility of diffusion basis spectrum imaging metrics at 7 T, confirmed the role of the derived metrics in the characterization of lesions and normal appearing white matter tissue in different stages of the disease and demonstrated their clinical relevance. Thus, suggesting that diffusion basis spectrum imaging is a promising tool to investigate multiple sclerosis pathophysiology, monitor disease progression and treatment response.


Assuntos
Axônios/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Encefalite/diagnóstico por imagem , Esclerose Múltipla/diagnóstico por imagem , Bainha de Mielina/patologia , Substância Branca/diagnóstico por imagem , Adulto , Encefalite/complicações , Encefalite/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Substância Branca/patologia
11.
Vascular ; 30(3): 448-454, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34024196

RESUMO

PURPOSE: To assess the efficacy and safety of the Orchid drug-coated balloon (coated with paclitaxel) for the treatment of femoropopliteal artery disease versus percutaneous transluminal angioplasty in Chinese population. METHODS: This is a prospective, single center, single-blinded, randomized controlled trial that randomized (1:1) 60 patients (38 men; mean age 68.7 ± 8.8) to drug-coated balloon group (n = 30) or percutaneous transluminal angioplasty group (n = 30). The primary efficacy endpoint was primary patency of the target lesion and clinically driven target lesion revascularization (CD-TLR) at 12 months. The primary safety end point was freedom from perioperative death at 30 days and freedom from limb-related death and major amputation at 12 months. RESULTS: Baseline characteristics were similar between the two groups. Drug-coated balloon group resulted in higher primary patency (82.8% vs. 48.3%, p = 0.005) and lower CD-TLR rates (3.5% vs. 27.6%; p = 0.001) versus percutaneous transluminal angioplasty group at 12 months. The ABI was significantly higher in drug-coated balloon group than percutaneous transluminal angioplasty group (0.86 ± 0.13 vs. 0.72 ± 0.18, p = 0.025). There were no perioperative death at 30 days, no limb-related death and no major amputation at 12 months in either group. CONCLUSIONS: The randomized controlled trial showed superior treatment effect with drug-coated balloon versus percutaneous transluminal angioplasty, with remarkably higher patency and lower CD-TLR rates. The result is consistent with other study and demonstrates the safety and efficacy of the Orchid drug-coated balloon for the treatment of femoropopliteal artery disease.


Assuntos
Angioplastia com Balão , Doença Arterial Periférica , Idoso , Angioplastia , Angioplastia com Balão/efeitos adversos , Materiais Revestidos Biocompatíveis , Artéria Femoral/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/patologia , Doença Arterial Periférica/terapia , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/cirurgia , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
12.
NMR Biomed ; 34(1): e4414, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33015890

RESUMO

Diffusion tensor imaging (DTI) has been employed for over 2 decades to noninvasively quantify central nervous system diseases/injuries. However, DTI is an inadequate simplification of diffusion modeling in the presence of coexisting inflammation, edema and crossing nerve fibers. We employed a tissue phantom using fixed mouse trigeminal nerves coated with various amounts of agarose gel to mimic crossing fibers in the presence of vasogenic edema. Diffusivity measures derived by DTI and diffusion basis spectrum imaging (DBSI) were compared at increasing levels of simulated edema and degrees of fiber crossing. Furthermore, we assessed the ability of DBSI, diffusion kurtosis imaging (DKI), generalized q-sampling imaging (GQI), q-ball imaging (QBI) and neurite orientation dispersion and density imaging to resolve fiber crossing, in reference to the gold standard angles measured from structural images. DTI-computed diffusivities and fractional anisotropy were significantly confounded by gel-mimicked edema and crossing fibers. Conversely, DBSI calculated accurate diffusivities of individual fibers regardless of the extent of simulated edema and degrees of fiber crossing angles. Additionally, DBSI accurately and consistently estimated crossing angles in various conditions of gel-mimicked edema when compared with the gold standard (r2 = 0.92, P = 1.9 × 10-9 , bias = 3.9°). Small crossing angles and edema significantly impact the diffusion orientation distribution function, making DKI, GQI and QBI less accurate in detecting and estimating fiber crossing angles. Lastly, we used diffusion tensor ellipsoids to demonstrate that DBSI resolves the confounds of edema and crossing fibers in the peritumoral edema region from a patient with lung cancer metastasis, while DTI failed. In summary, DBSI is able to separate two crossing fibers and accurately recover their diffusivities in a complex environment characterized by increasing crossing angles and amounts of gel-mimicked edema. DBSI also indicated better angular resolution compared with DKI, QBI and GQI.


Assuntos
Imagem de Difusão por Ressonância Magnética , Edema/diagnóstico por imagem , Modelos Biológicos , Fibras Nervosas/patologia , Imagens de Fantasmas , Nervo Trigêmeo/diagnóstico por imagem , Nervo Trigêmeo/patologia , Animais , Anisotropia , Imagem de Tensor de Difusão , Edema/patologia , Feminino , Humanos , Camundongos Endogâmicos C57BL , Substância Branca/diagnóstico por imagem
13.
Nanotechnology ; 33(10)2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34610593

RESUMO

p-type CuI films with optimized optoelectronic performance were synthesized by solid-phase iodination of Cu3N precursor films at room temperature. The effects of the deposition power of Cu3N precursors on the structural, electrical, and optical properties of the CuI films were systematically investigated. X-ray diffraction results show that all the CuI films possess a zinc-blende structure. When the deposition power of Cu3N precursors was 140 W, the CuI films present a high transmittance above 84% in the visible region, due to their smaller root-mean-square roughness values of 9.23 nm. Moreover, these films also have a low resistivity of 1.63 × 10-2Ω·cm and a boosted figure of merit of 140.7 MΩ-1. These results are significant achievements among various p-types TCOs, confirming the promising prospects of CuI as a p-type transparent semiconductor applied in transparent electronics.

14.
Proc Natl Acad Sci U S A ; 115(43): E10225-E10234, 2018 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-30297414

RESUMO

Repetitive electrical activity produces microstructural alteration in myelinated axons, which may afford the opportunity to noninvasively monitor function of myelinated fibers in peripheral nervous system (PNS)/CNS pathways. Microstructural changes were assessed via two different magnetic-resonance-based approaches: diffusion fMRI and dynamic T2 spectroscopy in the ex vivo perfused bullfrog sciatic nerves. Using this robust, classical model as a platform for testing, we demonstrate that noninvasive diffusion fMRI, based on standard diffusion tensor imaging (DTI), can clearly localize the sites of axonal conduction blockage as might be encountered in neurotrauma or other lesion types. It is also shown that the diffusion fMRI response is graded in proportion to the total number of electrical impulses carried through a given locus. Dynamic T2 spectroscopy of the perfused frog nerves point to an electrical-activity-induced redistribution of tissue water and myelin structural changes. Diffusion basis spectrum imaging (DBSI) reveals a reversible shift of tissue water into a restricted isotropic diffusion signal component. Submyelinic vacuoles are observed in electron-microscopy images of tissue fixed during electrical stimulation. A slowing of the compound action potential conduction velocity accompanies repetitive electrical activity. Correlations between electrophysiology and MRI parameters during and immediately after stimulation are presented. Potential mechanisms and interpretations of these results are discussed.


Assuntos
Axônios/patologia , Bainha de Mielina/patologia , Fibras Nervosas Mielinizadas/patologia , Animais , Anuros , Mapeamento Encefálico/métodos , Difusão , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Processamento de Imagem Assistida por Computador/métodos , Nervo Isquiático/patologia
15.
Foodborne Pathog Dis ; 18(8): 616-625, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34403269

RESUMO

While Shiga toxin-producing Escherichia coli (STEC) is a major foodborne pathogen worldwide, data on the molecular and phylogenetic properties of STEC isolates from retail beef samples in China remain scant. Fresh retail beef samples (n = 1062) were collected from eight provinces, and STEC isolates were recovered and characterized. PCR data showed that more than 50% of the samples were stx positive, and 82 STEC isolates were recovered from 14.8% (79/535) stx-positive enriched broths. In contrast, all ciprofloxacin resistant isolates (n = 19) and 13 cefotaxime (CTX) resistant isolates were eae positive and belonged to three serotypes: O111:H8, O26:H11, or O157:H7. Point mutations in quinolone resistance-determining regions and plasmid-mediated quinolone resistance determinants were identified in 16 and 20 isolates, respectively. BlaCTX-M and a point mutation (C-42T) in ampC promoter were detected in 15 and 8 of the CTX resistant isolates, respectively. In addition, macrolide resistance gene mphA was identified in eight azithromycin resistant O111:H8 isolates and one O26:H11 isolate. Single nucleotide polymorphism analysis demonstrated that the O26 and O157 isolates had multiple origins, but the O111 isolates were closely related. Taken together, our data demonstrated that several sequence types associated with hemolytic uremic syndrome from the retail beef samples in China had developed into dangerous multidrug resistant pathogens. The resistant phenotype can facilitate their transmission among the farm animals and human beings when there is an antimicrobial selective pressure.


Assuntos
Proteínas de Escherichia coli/isolamento & purificação , Microbiologia de Alimentos/estatística & dados numéricos , Carne Vermelha/microbiologia , Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/isolamento & purificação , Animais , China , Resistência a Múltiplos Medicamentos/genética , Humanos , Filogenia , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Sorogrupo , Fatores de Virulência/genética
16.
Biochem Biophys Res Commun ; 532(4): 598-604, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32900484

RESUMO

OBJECTIVE: Pulmonary fibrosis is a fatal interstitial lung disease that is characterized by excessive accumulation of extracellular matrix (ECM) and remodeling of lung. The precise mechanisms underlying pulmonary fibrosis still remain unclear. In the current study, we aimed to investigate the alteration and function of serine (or cysteine) peptidase inhibitor, clade A, member 3 N (Serpina3n) in pulmonary fibrotic models and explore the potential mechanisms. METHODS: We induced pulmonary fibrosis in mice by silica and bleomycin respectively and determined Serpina3n in lung tissues, and then verified the expression of Serpina3n and its correlation with pulmonary fibrosis at seven time points in a bleomycin longstanding model. Moreover, adeno-associated virus type 9 (AAV9)-mediated Serpina3n knockdown was used to treat pulmonary fibrosis in the bleomycin model, whose possible mechanisms would be preliminarily explored by detecting chymotrypsin C as an example. RESULTS: Serpina3n was up-regulated significantly in lungs of both models at mRNA and protein levels relative to control. Notably, the expression of Serpina3n peaked during the 3rd week and then decreased until nearly normal levels during the 10th week, which was closely related to fibrotic procession in bleomycin-treated mice. AAV-mediated Serpina3n knockdown in the lung tissues alleviated bleomycin-induced fibrotic symptoms at various levels and disinhibit chymotrypsin C. CONCLUSIONS: Our study revealed that Serpina3n is a critical regulator in pulmonary fibrosis and suggested Serpina3n inhibition as a potential therapeutic strategy in chronic pulmonary injuries.


Assuntos
Proteínas de Fase Aguda/fisiologia , Fibrose Pulmonar/metabolismo , Serpinas/fisiologia , Proteínas de Fase Aguda/genética , Proteínas de Fase Aguda/metabolismo , Animais , Bleomicina , Quimotripsina/metabolismo , Técnicas de Silenciamento de Genes , Camundongos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/enzimologia , Fibrose Pulmonar/patologia , Serpinas/genética , Serpinas/metabolismo , Regulação para Cima
17.
J Neuroinflammation ; 17(1): 64, 2020 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-32070376

RESUMO

BACKGROUND: Sepsis-associated acute brain inflammation, if unresolved, may cause chronic neuroinflammation and resultant neurodegenerative diseases. However, little is known how the transition from acute to chronic neuroinflammation, which is critical for the following progressive neurodegeneration, occurs in sepsis. The goal of this study was to investigate potential immune factors regulating the transition process using a widely used endotoxemia LPS mouse model. This model shows distinct acute and chronic phases of neuroinflammation and recapitulates many cardinal features of Parkinson's disease, thus, providing a unique opportunity for studying phase transition of neuroinflammation. METHODS: C57BL/6 J, NLRP3-/-, and IL-1R1-/- mice were employed. Mild and severe endotoxemia were produced by LPS ip injection at 1 or 5 mg/kg. Neuroinflammation in vitro and in vivo was assessed with proinflammatory cytokine expression by qPCR or ELISA and microglial activation by immunohistochemical analysis. Neurodegeneration was measured by manual and stereological counts of nigral dopaminergic neurons and immunohistochemical analysis of protein nitrosylation and α-synuclein phosphorylation. RESULTS: LPS-elicited initial increases in mouse brain mRNA levels of TNFα, IL-6, IL-1ß, and MCP-1, and nigral microglial activation were not dose-related. By contrast, the delayed increase in brain mature IL-1ß levels was dependent on LPS doses and protracted nigral microglial activation was only observed in high dose of LPS-treated mice. LPS-elicited increase in brain mature IL-1ß but not IL-1α level was NLRP3-dependent. After high dose LPS treatment, deficiency of NLRP3 or IL-1R1 did not prevent the initiation of acute neuroinflammation but abolished chronic neuroinflammation. Genetic or pharmacological inhibition of the NLRP3-IL-1ß axis repressed LPS-stimulated upregulation of chronic neuroinflammatory mediators including MHC-II, NOX2, and Mac1, and protected dopaminergic neurons. Ten months after LPS-elicited severe endotoxemia, nigral persisted microglial activation, elevated nitrosylated proteins and phosphorylated α-synuclein, and significant neuronal degeneration developed in wild-type mice but not in NLRP3-/- or IL-1R1-/- mice. CONCLUSIONS: This study uncovers a novel role of the NLRP3-IL-1ß signaling pathway in gauging the severity of sepsis-associated inflammation and determining whether acute neuroinflammation will resolve or transition to low grade chronic neuroinflammation. These findings also provide novel targets for developing therapy for severe systemic infection-related neurodegeneration.


Assuntos
Progressão da Doença , Mediadores da Inflamação/metabolismo , Interleucina-1beta/deficiência , Proteína 3 que Contém Domínio de Pirina da Família NLR/deficiência , Doenças Neurodegenerativas/metabolismo , Sepse/metabolismo , Doença Aguda , Animais , Células Cultivadas , Doença Crônica , Lipopolissacarídeos/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doenças Neurodegenerativas/induzido quimicamente , Sepse/induzido quimicamente
18.
Brain Behav Immun ; 87: 359-368, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31923552

RESUMO

Parkinson's disease (PD) develops over decades through spatiotemporal stages that ascend from the brainstem to the forebrain. The mechanism behind this caudo-rostral neurodegeneration remains largely undefined. In unraveling this phenomenon, we recently developed a lipopolysaccharide (LPS)-elicited chronic neuroinflammatory mouse model that displays sequential losses of neurons in brainstem, substantia nigra, hippocampus and cortex. In this study, we aimed to investigate the mechanisms of caudo-rostral neurodegeneration and focused our efforts on the earliest neurodegeneration of vulnerable noradrenergic locus coeruleus (NE-LC) neurons in the brainstem. We found that compared with neurons in other brain regions, NE-LC neurons in untreated mice displayed high levels of mitochondrial oxidative stress that was severely exacerbated in the presence of LPS-elicited chronic neuroinflammation. In agreement, NE-LC neurons in LPS-treated mice displayed early reduction of complex IV expression and mitochondrial swelling and loss of cristae. Mechanistically, the activation of the superoxide-generating enzyme NADPH oxidase (NOX2) on NE-LC neurons was essential for their heightened vulnerability during chronic neuroinflammation. LPS induced early and high expressions of NOX2 in NE-LC neurons. Genetic or pharmacological inactivation of NOX2 markedly reduced mitochondrial oxidative stress and dysfunction in LPS-treated mice. Furthermore, inhibition of NOX2 significantly ameliorated LPS-induced NE-LC neurodegeneration. More importantly, post-treatment with NOX2 inhibitor diphenyleneiodonium when NE-LC neurodegeneration had already begun, still showed high efficacy in protecting NE-LC neurons from degeneration in LPS-treated mice. This study strongly supports that chronic neuroinflammation and NOX2 expression among vulnerable neuronal populations contribute to caudo-rostral degeneration in PD.


Assuntos
Neurônios Adrenérgicos , Locus Cerúleo , Animais , Neurônios Dopaminérgicos , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos C57BL , Microglia
19.
Neurochem Res ; 45(8): 1941-1952, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32488470

RESUMO

Subacute exposure to manganese (Mn) produced Parkinson's disease-like syndrome called Manganism. Chronic onset and progression are characteristics of Manganism, therefore, this study aimed to examine Mn toxicity following chronic exposures. Male Sprague-Dawley rats were injected Mn2+ 1 and 5 mg/kg, every 10 days for 150 days (15 injections). Animal body weight and behavioral activities were recorded. At the end of experiments, the brain and liver were collected for morphological and molecular analysis. Chronic Mn exposure did not affect animal body weight gain, but the high dose of Mn treatment caused 20% mortality after 140 days of administration. Motor activity deficits were observed in a dose-dependent manner at 148 days of Mn administration. Immunofluorescence double staining of substantia nigra pars compacta (SNpc) revealed the activation of microglia and loss of dopaminergic neurons. The chronic neuroinflammation mediators TNFα, inflammasome Nlrp3, Fc fragment of IgG receptor IIb, and formyl peptide receptor-1 were increased, implicating chronic Mn-induced neuroinflammation. Chronic Mn exposure also produced liver injury, as evidenced by hepatocyte degeneration with pink, condensed nuclei, indicative of apoptotic lesions. The inflammatory cytokines TNFα, IL-1ß, and IL-6 were increased, alone with stress-related genes heme oxygenase-1, NAD(P)H:quinone oxidoreductase-1 and metallothionein. Hepatic transporters, such as multidrug resistant proteins (Abcc1, Abcc2, and Abcc3) and solute carrier family proteins (Slc30a1, Slc39a8 and Slc39a14) were increased in attempt to eliminate Mn from the liver. In summary, chronic Mn exposure produced neuroinflammation and dopaminergic neuron loss in the brain, but also produced inflammation to the liver, with upregulation of hepatic transporters.


Assuntos
Encéfalo/efeitos dos fármacos , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Neurônios Dopaminérgicos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Manganês/toxicidade , Síndromes Neurotóxicas/etiologia , Animais , Comportamento Animal/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Inflamação/induzido quimicamente , Injeções Intraperitoneais , Masculino , Manganês/administração & dosagem , Ratos Sprague-Dawley , Teste de Desempenho do Rota-Rod , Fatores de Tempo
20.
Inorg Chem ; 59(7): 4711-4719, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32191452

RESUMO

High-capacity germanium-based anode materials are alternative materials for outstanding electrochemical performance lithium-ion batteries (LIBs), but severe volume variation and pulverization problems during charging-discharging processes can seriously affect their electrochemical performance. In addressing this challenge, a simple strategy was used to prepare the self-assembled GeOX/Ti3C2TX composite in which the GeOX nanoparticles can grow directly on Ti3C2TX layers. Nanoscale GeOX uniformly renucleates on the surface and interlayers of Ti3C2TX, forming the stable multiphase structure, which guarantees its excellent electrochemical performance. Electrochemical evaluation has shown that the rate capability and reversibility of GeOX/Ti3C2TX are both greatly improved, which delivers a reversible discharge specific capacity of above 1400 mAh g-1 (at 100 mA g-1) and a reversible specific capacity of 900 mAh g-1 after 50 cycles while it still maintains a stable specific capacity of 725 mAh g-1 at 5000 mA g-1. Furthermore, the composite exhibits an exceptionally superior rate capability, making it a good electrochemical performance anode for LIBs.

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