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1.
Opt Express ; 32(2): 2321-2332, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38297765

RESUMO

Deep learning-based computer-generated holography (DeepCGH) has the ability to generate three-dimensional multiphoton stimulation nearly 1,000 times faster than conventional CGH approaches such as the Gerchberg-Saxton (GS) iterative algorithm. However, existing DeepCGH methods cannot achieve axial confinement at the several-micron scale. Moreover, they suffer from an extended inference time as the number of stimulation locations at different depths (i.e., the number of input layers in the neural network) increases. Accordingly, this study proposes an unsupervised U-Net DeepCGH model enhanced with temporal focusing (TF), which currently achieves an axial resolution of around 5 µm. The proposed model employs a digital propagation matrix (DPM) in the data preprocessing stage, which enables stimulation at arbitrary depth locations and reduces the computation time by more than 35%. Through physical constraint learning using an improved loss function related to the TF excitation efficiency, the axial resolution and excitation intensity of the proposed TF-DeepCGH with DPM rival that of the optimal GS with TF method but with a greatly increased computational efficiency.

2.
Clin Oral Investig ; 28(8): 439, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037593

RESUMO

OBJECTIVES: To conduct a finite element analysis of the impact of different variables on tooth sectioning efficiency and trauma to surrounding tissues when utilizing high-speed surgical handpieces and elevators. METHODS: CBCT data from the horizontally impacted third mandibular molar (M3M) of a patient were utilized to establish digital models of the M3M, adjacent M2M, and surrounding bone. To simulate tooth sectioning, a 3D finite element model was established with the following variables: remaining tooth tissue thickness (1-5 mm), tooth section fissure width (1-3 mm), elevator depth in fissure (2-6 mm), elevator position (buccal, lingual, central), elevator width (2-5 mm), and application of force (rotating, levering). Using this model, the distribution of stress on the M3M and the surrounding tissue was assessed while measuring tooth sectioning efficiency and trauma to the surrounding tissue. RESULTS: Factors associated with uniform stress at the site of sectioning included thin (≤ 3 mm) remaining tooth tissue, appropriate fissure width (~ 2 mm), a wide (≥ 4 mm) elevator, and central elevator positioning. Levering the elevator yielded greater stress on the M3M than rotating force. Greater sectioning efficiency was associated with increased stress placed on the distobuccal side of M2M. CONCLUSIONS: Tooth sectioning efficiency can be improved by adjusting the high-speed surgical handpiece and elevator. However, it is important to remain attentive to the trauma to which adjacent teeth are exposed during this process. CLINICAL SIGNIFICANCE: These results offer guidance for approaches to improving operator efficiency and reducing trauma to surrounding tissues during tooth sectioning.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Análise de Elementos Finitos , Mandíbula , Dente Serotino , Dente Impactado , Humanos , Dente Serotino/cirurgia , Dente Impactado/cirurgia , Dente Impactado/diagnóstico por imagem , Mandíbula/cirurgia , Imageamento Tridimensional , Equipamentos Odontológicos de Alta Rotação , Análise do Estresse Dentário
3.
J Org Chem ; 86(17): 12168-12180, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34346223

RESUMO

A palladium-catalyzed regiospecific decarboxylative ε-allylation of (cyclohexadienylidene)malononitriles is presented for the synthesis of functionalized α-allyl-α-aryl malononitriles. This reaction proceeds via a resonance-stabilized α-aryl malononitrile anion, resulting in a wide range of α-allyl-α-aryl malononitriles in high yields with excellent linear product selectivity. We have also shown that the resulting products can be transformed into valuable synthetic intermediates by decyanation and Mizoroki-Heck arylation. In addition, an enantioselective decarboxylative allylation reaction is also presented.

4.
Cardiology ; 139(3): 151-158, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29353286

RESUMO

OBJECTIVES: The importance of thrombocytopenia (TP) has been discussed previously. However, data are still limited, especially on predictors of TP. We sought to investigate predictors of TP after transcatheter aortic valve replacement (TAVR), in particular, clinically significant TP. METHODS: We reviewed a total of 123 consecutive patients undergoing TAVR in our medical center. They were stratified into 3 groups according to the nadir platelet count post-TAVR: no/mild TP, moderate TP, and severe TP. Clinically significant TP, also known as major TP, was defined as moderate-to-severe TP (a nadir platelet count <100 × 109/L and a >50% decrease in platelet count). RESULTS: Baseline platelet, baseline hemoglobin, general anesthesia (GA), valve malpositioning and post-TAVR left ventricular ejection fraction were found to be predictors of post-TAVR nadir platelet count. Major TP was associated with a higher risk of major bleeding (OR 3.524, 95% CI 1.546-8.031) and 1-month mortality (OR 11.226, 95% CI 1.208-104.328). Age (OR 1.110, 95% CI 1.014-1.215) and GA (OR 6.494, 95% CI 2.058-20.408) were predictors of major TP. CONCLUSION: Post-TAVR nadir platelet count can be predicted based on baseline and procedural data. Old age and GA contribute to clinically significant TP.


Assuntos
Estenose da Valva Aórtica/cirurgia , Trombocitopenia/etiologia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/mortalidade , Idoso , Idoso de 80 Anos ou mais , China , Feminino , Mortalidade Hospitalar , Humanos , Modelos Logísticos , Masculino , Análise Multivariada , Contagem de Plaquetas , Estudos Retrospectivos , Medição de Risco , Índice de Gravidade de Doença , Resultado do Tratamento , Função Ventricular Esquerda
5.
Heart Surg Forum ; 20(2): E052-E054, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-28481743

RESUMO

Primary cardiac tumors are extremely rare with occurrence range of about 0.0017-0.28%. Papillary fibroelastoma is a benign cardiac neoplasms. Improvement in the early diagnosis has been made possible with the help of high-resolution imaging technology, such as transesophageal echocardiography, combined with ischemic or embolic complications which patients typically present with clinically. We herein present a 51-year-old female patient with a papillary fibroelastoma on the aortic cusp, with its origin from the left coronary sinus. Her only clinical manifestation was angina-like chest pain and syncope. Surgical resection with aortic valve replacement due to the defect as a result of the resected tumor was performed with the patient on cardiopulmonary bypass. The patient recovered uneventfully and was discharged.  A 2-year follow-up showed an intact valve without tumor recurrence.


Assuntos
Seio Coronário/diagnóstico por imagem , Estenose Coronária/etiologia , Fibroma/diagnóstico , Neoplasias Cardíacas/diagnóstico , Procedimentos Cirúrgicos Cardíacos , Angiografia por Tomografia Computadorizada , Estenose Coronária/diagnóstico , Estenose Coronária/cirurgia , Diagnóstico Diferencial , Ecocardiografia Transesofagiana , Feminino , Fibroma/complicações , Fibroma/cirurgia , Neoplasias Cardíacas/complicações , Neoplasias Cardíacas/cirurgia , Ventrículos do Coração , Humanos , Pessoa de Meia-Idade
6.
J Neuroinflammation ; 13(1): 180, 2016 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-27391369

RESUMO

BACKGROUND: Reactive astrogliosis is a remarkable pathogenetic hallmark of the brains of Parkinson's disease (PD) patients, but its progressive fate and regulation mechanisms are poorly understood. In this study, growth arrest specific 1 (Gas1), a tumor growth suppressor oncogene, was identified as a novel modulator of the cell apoptosis of reactive astrocytes in primary culture and the injured substantia nigra. METHODS: Animal models and cell cultures were utilized in the present study. Lipopolysaccharide (LPS)- and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated animal models were used to detect Gas1 expression in the brain via immunohistochemistry and western blot. Cell cultures were performed to analyze Gas1 functions in the viability and apoptosis of reactive astrocytes and SH-SY5Y cells by double labeling, CCK-8, LDH, TUNEL, flow cytometry, and siRNA knockdown methods. RESULTS: Gas1 expressions were significantly elevated in the majority of the reactive astrocytes of the brains with LPS or MPTP insults. In the injured substantia nigras, GFAP-positive astrocytes exhibited higher levels of cleaved caspase-3. In cell culture, the up-regulated Gas1 expression induced apoptosis of reactive astrocytes that were insulted by LPS in combination with interferon-γ and tumor necrosis factor-a. This effect was confirmed through siRNA knockdown of Gas1 gene expression. Finally and interestingly, the potential underlying signaling pathways were evidently related to an increase in the Bax/Bcl-2 ratio, the abundant generation of reactive oxygen species and the activation of cleaved caspase-3. CONCLUSIONS: This study demonstrated that the up-regulation of inducible Gas1 contributed to the apoptosis of reactive astrocytes in the injured nigra. Gas1 signaling may function as a novel regulator of astrogliosis and is thus a potential intervention target for inflammatory events in PD conditions.


Assuntos
Apoptose/fisiologia , Astrócitos/metabolismo , Proteínas de Ciclo Celular/biossíntese , Intoxicação por MPTP/metabolismo , Substância Negra/metabolismo , Regulação para Cima/fisiologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Linhagem Celular Tumoral , Células Cultivadas , Proteínas Ligadas por GPI/biossíntese , Humanos , Lipopolissacarídeos/toxicidade , Intoxicação por MPTP/patologia , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Sprague-Dawley , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Regulação para Cima/efeitos dos fármacos
7.
Zhonghua Wai Ke Za Zhi ; 54(2): 125-8, 2016 Feb 01.
Artigo em Chinês | MEDLINE | ID: mdl-26876080

RESUMO

OBJECTIVE: To evaluate whether intraoperative autologous donation (IAD) can reduce perioperative blood transfusion for patients underwent mitral valve replacement (MVR). METHODS: A total of 318 patients received implementation of IAD from January 2011 to December 2013 were analyzed retrospectively, and compared with 517 patients of the previous 36-month period (from January 2008 to December 2012). The method of small-volume retrograde autologous priming, strict blood transfusion standard along with IAD together constituted a progressive blood-saving strategy. Statistical methods including Students' t-test, Pearson's χ(2) test, Kruskal-Wallis analysis and multivariate Logistic regression model were used for comparisons of the data. RESULTS: There were no significant difference between IAD group and non-IAD group considering preoperative patient demographics, characteristics and preoperative comorbidities. However, IAD group significantly reduced number of patients transfused with intra/post-operative packed red-blood cell (PRBC) (55(17.0%) vs. 215 (42.1%), χ(2)=53.0, P=0.000), and had significantly reduced postoperative chest tube output (150(380) ml vs. 700(660) ml, H=195.648, P=0.000), length of stay ((16±6) d vs. (20±8)d, t=9.60, P=0.000). But hematocrit were lower in IAD group (30%±5% vs.33%±4% at end of operation, t=7.76, P=0.000; 30%±4% vs. 32%±5% at discharge, P=0.000, t=3.86). Multivariate logistic aggression analysis revealed that age, IAD and smoking history were factors influencing the probability of intra or postoperative blood transfusion. CONCLUSION: Implementation of blood conservation strategies based on intraoperative autologous donation in mitral valve replacement surgery can significantly reduce intra/postoperative blood transfusion as well as postoperative complications.


Assuntos
Procedimentos Médicos e Cirúrgicos sem Sangue , Procedimentos Cirúrgicos Cardíacos/métodos , Valva Mitral/cirurgia , Transfusão de Sangue Autóloga , Hematócrito , Humanos , Modelos Logísticos , Complicações Pós-Operatórias , Estudos Retrospectivos
8.
Sheng Li Ke Xue Jin Zhan ; 46(3): 170-4, 2015 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-26521480

RESUMO

Neurotrophic factor is a kind of protein family that plays an important role in the nutrition, support and differentiation to central neurons as well as synaptic plasticity. Growing evidences have revealed that pro-forms of various neurotrophic factors, which are generated in process of protein synthesis and might exert opposite roles involving in inducement of neuronal apoptosis and implication in pathogenesis of neurodegenerative diseases. This paper reviews "Yin/Yang" features of neurotrophic factors in the anabolism, receptor regulation, functional aspects, and their related role in pathogenesis of neurodegenerative diseases. It is hopefully to provide new idea on understanding and investigation of the neurotrophic factors regarding on their functional, pathological and potential therapeutic significance.


Assuntos
Neurônios , Apoptose , Humanos , Fatores de Crescimento Neural , Doenças Neurodegenerativas , Plasticidade Neuronal
9.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 42(4): 415-425, 2024 Aug 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-39049628

RESUMO

Biodegradable magnesium-based metal guided bone regeneration (GBR) membranes possess excellent mechanical properties, biodegradability, and osteopromotive capabilities, making them ideal implants for the treatment of maxillofacial bone defects. This review summarizes the current status and future research trends related to magnesium-based GBR membranes. First, the research history and application fields of magnesium-based metals are introduced, and the advantages of the use of magnesium-based materials for GBR membranes, including their mechanical properties, biocompatibility, osteopromotive performance, and underlying mechanisms are discussed. Finally, this review addresses the current limitations of magnesium-based GBR membranes and their applications and prospects in the field of dentistry. In conclusion, considerable advancements have been in fundamental and translational research on magnesium-based GBR membranes, which lays a crucial foundation for the treatment of maxillofacial bone defects.


Assuntos
Materiais Biocompatíveis , Regeneração Óssea , Magnésio , Humanos , Implantes Absorvíveis , Regeneração Tecidual Guiada , Membranas Artificiais , Metais
10.
Materials (Basel) ; 17(14)2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39063780

RESUMO

This study investigated the corrosion resistance and mechanical properties of Mg-2Zn-0.46Y-0.5Nd (wt.%) alloy plates and screws with fluorinated coatings and atomic layer deposition (ALD)-derived zirconia (ZrO2) coatings in vitro under physiological stress conditions. Synthetic polyurethane hemimandible replicas were split and fixed as the following three groups of magnesium alloy plates and screws: no additional surface coating treatment (Group A), with fluorinated coatings (Group B), and with duplex fluorinated and ALD-derived 100 nm ZrO2 coatings (Group C). A circulating stress of 1-10 N was applied to the distal bone segment, and a 4-week simulated body fluid immersion test was employed to study the remaining material volume and the mechanical properties of the different groups. Compared with Group A and Group B, the degradation rate of magnesium alloy plates and screws' head regions was significantly slowed down under the protection of duplex MgF2/ZrO2 coatings (p < 0.01). There was no significant difference in the degradation rate of the screw shaft region between groups (p = 0.077). In contrast to fluoride coatings, duplex MgF2/ZrO2 coatings maintained the mechanical strength of magnesium alloy plates and screws after a 14 day in vitro SBF immersion test. We conclude that duplex MgF2/ZrO2 coatings exhibited a certain protective effect on the Mg alloy plates and screws under physiological stress conditions.

11.
J Interferon Cytokine Res ; 44(2): 68-79, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38153396

RESUMO

Macrophages are crucial immune cells that play essential roles in the healing of myocardial infarction (MI), undergoing continuous polarization throughout this process. C-C motif chemokine 2 (CCL2) is a chemokine that regulates inflammatory responses during MI. However, the extent to which CCL2 influences macrophage polarization and MI healing remains incompletely understood. In this study, we investigate the role of CCL2 in macrophage polarization and MI healing. Our findings reveal that CCL2 is differentially expressed in lipopolysaccharide (LPS)-induced M1 and interleukin (IL)-4-induced M2 RAW264.7 macrophages. Knockdown of CCL2 attenuates TNF-α secretion stimulated by LPS, while overexpression of CCL2 mitigates IL-10 production triggered by IL-4 in these macrophages. Moreover, CCL2 deficiency disrupts LPS-induced M1 polarization, whereas CCL2 overexpression reduces M2 polarization of RAW264.7 macrophages induced by IL-4. Further exploration indicates that the promotion of M1 polarization by CCL2 is significantly impaired by inhibition of the p38-mediated MAPK pathway and NF-κB pathway. In a MI mouse model, CCL2 knockdown remarkably reduces infarct size, collagen synthesis, and the expression of cardiac fibrosis and hypertrophy markers. The activity of the p38-mediated MAPK pathway and NF-κB pathway is downregulated by CCL2 knockdown as well. Additionally, the number of total macrophages and M1 macrophages in the infarct decreases, while the number of M2 macrophages increases upon CCL2 deficiency. In conclusion, these results suggest that CCL2 is a key regulator of macrophage polarization, controlling MI healing in vivo.


Assuntos
Interleucina-4 , Infarto do Miocárdio , Animais , Camundongos , Interleucina-4/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , NF-kappa B/metabolismo
12.
J Colloid Interface Sci ; 675: 958-969, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39002245

RESUMO

Graphene oxide (GO) membranes have emerged as promising candidates for water purification applications, owing to their unique physicochemical attributes. Nevertheless, the trade-off between permeability and selectivity, coupled with their vulnerability to membrane fouling, poses significant challenges to their widespread industrial deployment. In this study, we introduce an innovative in-situ growth and layer-by-layer assembly technique for fabricating multilayer GO membranes reinforced with bismuth oxybromide (BiOBr) on commonly employed Nylon substrates. This method allows for the creation of two-dimensional lamellar membranes capable of photocatalytic self-cleaning and tunable nanochannel dimensions. The synthesized GO/BiOBr composite membranes exhibit remarkable water permeance rates (approximately 493.9 LMH/bar) and high molecular rejection efficiency (>99 % for Victoria Blue B and Congo Red dyes). Notably, these membranes showcase an enhanced photocatalytic self-cleaning performance upon exposure to visible light. Our work provides a viable route for the fabrication of functionalized GO-based nanofiltration membranes with BiOBr inclusions, offering a synergistic combination of high water permeability, modifiable nanochannels, and effective self-cleaning capabilities through photocatalysis.

13.
Dalton Trans ; 53(6): 2703-2713, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38226458

RESUMO

The SrCoO3-δ system has broad application potential due to its diverse crystal structures, oxidation stoichiometric ratio, and significant electrical and magnetic properties. However, it faces the challenges of a complex crystal structure and oxygen defect control in this material system. Herein, we introduce oxygen defects into SrCoO3-δvia Er doping to regulate the structural, electrical and magnetic transport properties. Sr1-xErxCoO3-δ (x = 0-0.25) undergoes an evolution of structure and oxygen content (measured using the iodometric method) from hexagonal SrCoO2.626 (H + Co3O4) to cubic perovskite Sr0.9Er0.1CoO2.689 (CP) and finally to ordered tetragonal Sr0.8Er0.2CoO2.635 (OT). Among the three phases, Sr0.9Er0.1CoO2.689 (CP) exhibits the lowest resistivity, only 4.06 mΩ cm at room temperature, which is attributed to its high three-dimensional symmetry, overlap of O 2p and Co 3d orbitals at high oxygen ion concentration. Further introduction of Er ions and oxygen defects promotes the transformation from low spin Co4+ (LS, t52ge0g, S = 1/2) to high spin Co3+ (HS, t42ge2g, S = 2), and from the CoO6 octahedron (low magnetic moment transformation) to the CoO4.25 tetrahedron (high magnetic moment). The oxygen-deficient CoO4.25 layer appears, which can enhance the ordering of A sites and oxygen vacancies, and the CP phase transforms into room-temperature ferromagnetic Sr0.8Er0.2CoO2.635 (OT, TC∼330 K). Er ions provide unpaired electrons in the 2f orbital, which results in a strong magnetization of Sr0.8Er0.2CoO2.635 (OT, 4.66 µB/Co) at low temperatures.

14.
Chem Commun (Camb) ; 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39301691

RESUMO

A carboxylate-directed regioselective Heck-type alkenylation and alkenylative lactonization of (E)-ß,γ-unsaturated carboxylic acids by simply substrate control is reported. (E)- and (Z)-alkenyl bromides reacted to give energetically more favorable palladacyles, allowing access to fully stereocontrolled conjugated 1,3-dienes and alkenyled γ-lactones. Mechanistic studies suggest that excellent regioselectivity may be strongly influenced by the steric factors of reactants involved in the palladacycle intermediates.

15.
J Neurosci Res ; 91(1): 30-41, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23023811

RESUMO

Brain-derived neurotrophic factor (BDNF) has critical functions in promoting survival, expansion, and differentiation of neural stem cells (NSCs), but its downstream regulation mechanism is still not fully understood. The role of BDNF in proliferation and differentiation of NSCs through Wnt/ß-catenin signaling was studied via cell culture of cortical NSCs, Western blotting, immunocytochemistry, and TOPgal (Wnt reporter) analysis in mice. First, BDNF stimulated NSC proliferation dose dependently in cultured neurospheres that exhibited BrdU incorporation and neuronal and glial differentiation abilities. Second, BDNF effectively enhanced cell commitment to neuronal and oligodendrocytic fates, as indicated by increased differentiation marker Tuj-1 (neuronal marker), CNPase (oligodendrocyte marker), and neuronal process extension. Third, BDNF upregulated expression of Wnt/ß-catenin signaling (Wnt1 and free ß-catenin) molecules. Moreover, these promoting effects were significantly inhibited by application of IWR1, a Wnt signaling-specific blocker in culture. The TOPgal mouse experiment further confirmed BDNF-triggered Wnt signaling activation by ß-gal labeling. Finally, an MEK inhibition experiment showed a mediating role of the microtubule-associated protein kinase pathway in BDNF-triggered Wnt/ß-catenin signaling cascades. This study overall has revealed that BDNF might contribute to proliferation and neuronal and oligodendrocytic differentiation of NSCs in vitro, most possibly by triggering the Wnt/ß-catenin signaling pathway. Nevertheless, determining the exact cross-talk points at which BDNF might stimulate Wnt/ß-catenin signaling pathway in NSC activity requires further investigation.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Diferenciação Celular/fisiologia , Proliferação de Células , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Via de Sinalização Wnt/fisiologia , Animais , Western Blotting , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Confocal
16.
Hepatology ; 56(3): 803-11, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22271421

RESUMO

UNLABELLED: Human MxA, an interferon-inducible cytoplasmic dynamin-like GTPase, possesses antiviral activity against multiple RNA viruses. Recently, MxA has also been demonstrated to have activity against the hepatitis B virus (HBV), a well-known DNA virus responsible for acute and chronic liver disease in humans. We investigated the molecular mechanism for the anti-HBV activity of MxA. Our results demonstrated that in HepG2.2.15 cells, MxA GTPase independently suppressed the production of hepatitis B surface antigen and HBV DNA without changing the level of hepatitis B core antigen (HBcAg) and the distribution of HBV mRNA. MxA significantly reduced the level of the encapsidated pregenomic RNA. Through its central interactive domain, MxA interacted with HBcAg, causing accumulation of the proteins in perinuclear compartments. MxA-HBcAg interaction significantly affected the dynamics of HBcAg by immobilizing HBcAg in the perinuclear structures. CONCLUSION: MxA displays antiviral activity against HBV involving a mechanism of MxA-HBcAg interaction that may interfere with core particle formation.


Assuntos
Proteínas de Ligação ao GTP/farmacologia , Antígenos do Núcleo do Vírus da Hepatite B/efeitos dos fármacos , Antígenos do Núcleo do Vírus da Hepatite B/fisiologia , Vírus da Hepatite B/fisiologia , Replicação Viral/efeitos dos fármacos , Células Cultivadas , Humanos , Proteínas de Resistência a Myxovirus
17.
Int J Mol Sci ; 14(7): 14085-104, 2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-23880857

RESUMO

Growing evidence has shown that proNGF-p75NTR-sortilin signaling might be a crucial factor in neurodegeneration, but it remains unclear if it may function in nigral neurons under aging and disease. The purpose of this study is to examine and quantify proNGF and sortilin expression in the substantia nigra and dynamic changes of aging in lactacystin and 6-hydroxydopamine (6-OHDA) rat models of Parkinson's disease using immunofluorescence, electronic microscopy, western blot and FLIVO staining methods. The expression of proNGF and sortilin was abundantly and selectively identified in tyrosine hydroxylase (TH)-containing dopamine neurons in the substantia nigra. These proNGF/TH, sortilin/TH-positive neurons were densely distributed in the ventral tier, while they were less distributed in the dorsal tier, where calbindin-D28K-containing neurons were numerously located. A correlated decrease of proNGF, sortilin and TH was also detected during animal aging process. While increase of proNGF, sortilin and cleaved (active) caspase-3 expression was found in the lactacystin model, dynamic proNGF and sortilin changes along with dopamine neuronal loss were demonstrated in the substantia nigra of both the lactacystin and 6-OHDA models. This study has thus revealed the presence of the proNGF-sortilin signaling complex in nigral dopamine neurons and its response to aging, lactacystin and 6-OHDA insults, suggesting that it might contribute to neuronal apoptosis or neurodegeneration during pathogenesis and disease progression of Parkinson's disease; the underlying mechanism and key signaling pathways involved warrant further investigation.


Assuntos
Acetilcisteína/análogos & derivados , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Envelhecimento , Antibacterianos/toxicidade , Fator de Crescimento Neural/metabolismo , Oxidopamina/toxicidade , Substância Negra/efeitos dos fármacos , Acetilcisteína/toxicidade , Animais , Apoptose/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/enzimologia , Neurônios Dopaminérgicos/metabolismo , Proteínas do Tecido Nervoso , Precursores de Proteínas/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Fatores de Crescimento , Receptores de Fator de Crescimento Neural/metabolismo , Transdução de Sinais/efeitos dos fármacos , Substância Negra/metabolismo , Substância Negra/patologia , Tirosina 3-Mono-Oxigenase/metabolismo
18.
IEEE Trans Neural Netw Learn Syst ; 34(8): 5212-5217, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34793308

RESUMO

Knowledge-based dialog systems have attracted increasing research interest in diverse applications. However, for disease diagnosis, the widely used knowledge graph (KG) is hard to represent the symptom-symptom and symptom-disease relations since the edges of traditional KG are unweighted. Most research on disease diagnosis dialog systems highly relies on data-driven methods and statistical features, lacking profound comprehension of symptom-symptom and symptom-disease relations. To tackle this issue, this work presents a weighted heterogeneous graph-based dialog system for disease diagnosis. Specifically, we build a weighted heterogeneous graph based on symptom co-occurrence and the proposed symptom frequency-inverse disease frequency. Then, this work proposes a graph-based deep Q -network (graph-DQN) for dialog management. By combining graph convolutional network (GCN) with DQN to learn the embeddings of diseases and symptoms from both the structural and attribute information in the weighted heterogeneous graph, graph-DQN could capture the symptom-disease relations and symptom-symptom relations better. Experimental results show that the proposed dialog system rivals the state-of-the-art models. More importantly, the proposed dialog system can complete the task with fewer dialog turns and possess a better distinguishing capability on diseases with similar symptoms.

19.
Polymers (Basel) ; 15(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36987355

RESUMO

Adhesive joints possess a number of advantages over traditional joining methods and are widely used in composite structures. Conventional non-destructive examination techniques do not readily reveal joint degradation before the formation of explicit defects. Embedded fiber Bragg grating (FBG) sensors and the resistance of carbon nanotube (CNT)-doped conductive joints have been proposed to monitor the structural integrity of adhesive joints. Both techniques will be employed and compared in the current work to monitor damage development in adhesive joints under tensile and cyclic fatigue loading. Most of the previous works took measurements under an applied load, which by itself will affect the monitoring signals without the presence of any damage. Moreover, most FBG works primarily relied on the peak shifting phenomenon for sensing. Degradation of adhesive and inter-facial defects will lead to non-uniform strain that may chirp the FBG spectrum, causing complications in the peak shifting measurement. In view of the above shortfalls, measurements are made at some low and fixed loads to preclude any unwanted effect due to the applied load. The whole FBG spectrum, instead of a single peak, will be used, and a quantitative parameter to describe spectrum changes is proposed for monitoring purposes. The extent of damage is revealed by a fluorescent penetrant and correlated with the monitoring signals. With these refined techniques, we hope to shed some light on the relative merits and limitations of the two techniques.

20.
Gene ; 851: 147001, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36279950

RESUMO

BACKGROUND: The common genetic signatures of ascending aortic dilation and acute type A aortic dissection (AAAD) remained unclear. This study aims to investigate the role of ESR1 in ascending aortic dilation and AAAD via a multi-omics approach combining transcriptome-wide association study (TWAS) and mRNA expression profiles. METHODS: The TWAS analysis was performed by integrating expression quantitative trait loci (eQTL) data of aorta and the GWAS dataset of ascending aortic diameter using the FUSION software. Joint/Conditional Analysis was used to screen conditionally independent genes from TWAS significant regions. mRNA expression profiles were used to confirm the differential expression of ESR1 in ascending aortic dilation and AAAD. An independent mRNA expression profile dataset was used to validate the diagnostic efficiency of ESR1 expression on thoracic aortic aneurysm (TAA). Gene set enrichment analysis (GSEA) was utilized to explore the potential molecular function of ESR1 in mouse aorta. Immune infiltration analysis was performed to evaluate the association between ESR1 and immune infiltration in AAAD. RESULTS: ESR1 was among the top 10 most significant genes identified by TWAS of ascending aortic diameter (Z score = -7.3, PTWAS = 3.30 × 10-13). mRNA expression profiles confirmed the low expression of ESR1 both in ascending aortic dilation (PmRNA = 0.0361) and AAAD (PmRNA = 0.0142). The diagnostic efficiency of peripheral blood ESR1 expression on TAA was further validated by an independent mRNA expression profile dataset. GSEA showed that GO terms and KEGG pathways mainly involved in metabolism and oxidoreductase activity were enriched in aortic tissue of ERα knockout mice. The immune infiltration ration of naive CD8 + T cells was significantly lower in AAAD compared with normal aorta, and was positively correlated with ESR1 expression. CONCLUSION: Low expression of ESR1 is associated with ascending aortic dilation and AAAD. Peripheral blood ESR1 expression may be a novel diagnostic biomarker of TAA. ESR1 expression is positively correlated with immune infiltration ration of naive CD8 + T cells in AAAD.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Animais , Camundongos , Dilatação , Perfilação da Expressão Gênica , Transcriptoma , Dissecção Aórtica/genética , RNA Mensageiro/metabolismo , Aneurisma da Aorta Torácica/genética , Camundongos Knockout
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