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1.
Sensors (Basel) ; 24(7)2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38610270

RESUMO

The robotic drilling of assembly holes is a crucial process in aerospace manufacturing, in which measuring the normal of the workpiece surface is a key step to guide the robot to the correct pose and guarantee the perpendicularity of the hole axis. Multiple laser displacement sensors can be used to satisfy the portable and in-site measurement requirements, but there is still a lack of accurate analysis and layout design. In this paper, a simplified parametric method is proposed for multi-sensor normal measurement devices with a symmetrical layout, using three parameters: the sensor number, the laser beam slant angle, and the laser spot distribution radius. A normal measurement error distribution simulation method considering the random sensor errors is proposed. The measurement error distribution laws at different sensor numbers, the laser beam slant angle, and the laser spot distribution radius are revealed as a pyramid-like region. The influential factors on normal measurement accuracy, such as sensor accuracy, quantity and installation position, are analyzed by a simulation and verified experimentally on a five-axis precision machine tool. The results show that increasing the laser beam slant angle and laser spot distribution radius significantly reduces the normal measurement errors. With the laser beam slant angle ≥15° and the laser spot distribution radius ≥19 mm, the normal measurement error falls below 0.05°, ensuring normal accuracy in robotic drilling.

2.
Materials (Basel) ; 17(2)2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-38255464

RESUMO

CFRP/Ti stacks composed of carbon fiber-reinforced plastic composites (CFRP) and titanium alloys (Ti) are widely used in aerospace fields. However, in the integrated hole-making process of CFRP/Ti stacks, the machining characteristics of various materials are significantly different, and constant machining parameters cannot simultaneously meet the high-quality machining requirements of two materials. In addition, errors exist between the actual thickness of each material layer and the theoretical value, which causes an impediment to the monitoring of the machining interface and the corresponding adjustment of parameters. An adaptive machining method for the helical milling of CFRP/Ti stacks based on interface identification is proposed in this paper. The machining characteristics of the pneumatic spindle and the interface state in the helical milling of CFRP/Ti stacks are analyzed using self-developed portable helical milling equipment, and a new algorithm for the real-time monitoring of the machining interface position and adaptive adjustment of the machining parameters according to the interface identification result is proposed. Helical milling experiments were carried out, the results show that the proposed method can effectively identify the position of the machining interface with good identification accuracy. Moreover, the proposed parameter-adaptive optimized machining method for CFRP/Ti stacks can significantly improve hole diameter accuracy and machining quality.

3.
Cell Discov ; 10(1): 1, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172113

RESUMO

Thirst plays a vital role in the regulation of body fluid homeostasis and if deregulated can be life-threatening. Interoceptive neurons in the subfornical organ (SFO) are intrinsically osmosensitive and their activation by hyperosmolarity is necessary and sufficient for generating thirst. However, the primary molecules sensing systemic osmolarity in these neurons remain elusive. Here we show that the mechanosensitive TMEM63B cation channel is the osmosensor required for the interoceptive neurons to drive thirst. TMEM63B channel is highly expressed in the excitatory SFO thirst neurons. TMEM63B deletion in these neurons impaired hyperosmolarity-induced drinking behavior, while re-expressing TMEM63B in SFO restored water appetite in TMEM63B-deficient mice. Remarkably, hyperosmolarity activates TMEM63B channels, leading to depolarization and increased firing rate of the interoceptive neurons, which drives drinking behavior. Furthermore, TMEM63B deletion did not affect sensitivities of the SFO neurons to angiotensin II or hypoosmolarity, suggesting that TMEM63B plays a specialized role in detecting hyperosmolarity in SFO neurons. Thus, our results reveal a critical osmosensor molecule for the generation of thirst perception.

4.
Inorg Chem ; 63(2): 1378-1387, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38164710

RESUMO

The zero-valent iron (ZVI) has attracted increasing attention due to the enhanced reactivity of ZVI to uranium wastewater. However, ZVI practical application is hampered due to its susceptibility to oxidation and the formation of passivation layers during storage and in situ restoration. To address these issues, we used a biosulfuration approach to modify ZVI for application in uranium ore wastewater treatment. A series of physicochemical characterization tools and photoelectronic analyses showed that BS-ZVI considerably increased carrier separation efficiency and visible light absorption capacity, resulting in a significant photoassisted enhancement effect on uranium extraction. Accordingly, the uranium removal efficiency of BS-ZVI reached 91% within 60 min, and its maximum adsorption capacity was 336.3 mg/g. By analyzing the mechanism, the improved U(VI) removal performance was mostly responsible on the dissolution of the passivation layer on the surface of ZVI, the generation of Fe(II) and FeS, and the important role of Shewanella putrefaciens extracellular polymers (EPS). Overall, the BS-ZVI biohybrid merges with the high activity of ZVI, bio-FeS, and self-regeneration ability of bacteria, expanding a promising new approach for sustainable treatment of uranium mine wastewater.

5.
Int Immunopharmacol ; 127: 111458, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38160565

RESUMO

BACKGROUND: Sepsis is a disorder characterized by host inflammation and is caused by systemic infection. The inflammatory cytokine storm results in platelet overactivation, leading to coagulation dysfunction and thrombosis, but the underlying mechanism remains poorly understood. Recent evidence has shown that the Wnt/ß-catenin signaling pathway is related to sepsis, but its role and mechanism in sepsis complicated with deep vein thrombosis (DVT) are unclear. METHODS: In this study, a cecal ligation and puncture (CLP)-induced sepsis model and DVT mouse model were constructed by inferior vena cava ligation. The levels of serum inflammatory factors and adhesion molecules were measured in each group, and the thrombus weight and size, hematoxylin-eosin staining, collagen fiber tissue, and transcriptome of the venous wall were analyzed. The activation of the Wnt/ß-catenin signal was evaluated by quantitative real-time polymerase chain reaction, Western blotting, ELISA, and immunohistochemical and immunofluorescence methods. RESULTS: Sepsis significantly promoted the formation of venous wall collagen fibers and DVT. In addition, Porcn significantly upregulated and activated the Wnt/ß-catenin signaling pathway in sepsis mouse models with DVT. In contrast, the Wnt signaling inhibitor LGK974 was found to improve the survival rate, decrease thrombosis, and inhibit the expression of inflammation and adhesion molecules in sepsis mice with DVT. Therefore, activation of the Wnt/ß-catenin signal may promote the formation of DVT in sepsis mice. CONCLUSIONS: LGK974 protects against DVT formation in sepsis mice by inhibiting the activation of the Wnt/ß-catenin signal and down-regulating the production of proinflammatory cytokines, PAI-1, and adhesion molecules. LGK974 may be a new candidate for the treatment of sepsis complicated with DVT.


Assuntos
Pirazinas , Piridinas , Sepse , Trombose Venosa , Camundongos , Animais , beta Catenina , Trombose Venosa/tratamento farmacológico , Modelos Animais de Doenças , Inflamação , Sepse/complicações , Sepse/tratamento farmacológico , Colágeno/metabolismo
6.
ACS Omega ; 6(13): 9196-9203, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33842788

RESUMO

Transient receptor potential canonical channel 6 (TRPC6) has been implicated in many kinds of malignant tumors, but very few potent TRPC6 antagonists are available. In this study, a benzothiazole amide derivative 1a was discovered as a TRPC6 activator in a cell-based high-throughput screening. A series of benzothiazole amide derivatives were designed and synthesized. The docking analyses indicated that the conformations of the compounds bound to TRPC6 determined the agonistic or antagonistic activity of the compounds against TRPC6, and compound 1s with the tetrahydronaphthalene group in R1 position fit well into the binding pocket of the antagonist-bound conformation of TRPC6. Compound 1s showed an inhibitory potency order of TRPC3 (IC50 3.3 ± 0.13 µM) ≈ C6 (IC50 4.2 ± 0.1 µM) > C7 with good anti-gastric cancer activity in a micromolecular range against AGS and MKN-45, respectively. In addition, 1s inhibited the invasion and migration of MKN-45 cells in vitro.

7.
Fitoterapia ; 137: 104150, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30995564

RESUMO

Schefflera kwangsiensis Merr. ex H.L. Li (Araliaceae) is a widely used traditional Chinese medicine for pain management in the clinic. In the present study, we isolated a previously undescribed lupane saponin, designated as schekwanglupaside C (Sch C) from the ethanolic extract of S. kwangsiensis. The structure of Sch C was determined by comprehensive spectroscopic and spectrometric analyses and chemical degradation. In primary cultured cortical neurons, Sch C altered the pattern of spontaneous Ca2+ oscillation (SCO) with a slight increase in the frequency of SCO right after addition and a gradual decrease in the frequency and amplitude of SCO, that dynamic change mimicked by an activator of sarcoplasmic reticulum Ca2+-ATPase (SERCA). The IC50 values for Sch C suppression of the frequency and amplitude of SCO were 1.75 and 2.51 µM, respectively. Furthermore, we demonstrated that Sch C is a potent SERCA activator (EC50 = 1.20 µM). Given the pivotal role of SERCA in the progression of neuropathic pain and neurodegenerative diseases, Sch C represents a new drug lead compound to develop the treatment of neuropathic pain and Alzheimer's disease.


Assuntos
Araliaceae/química , Neurônios/efeitos dos fármacos , Saponinas/farmacologia , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Triterpenos/farmacologia , Animais , Cálcio/metabolismo , Células Cultivadas , China , Feminino , Masculino , Camundongos Endogâmicos C57BL , Estrutura Molecular , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/química , Saponinas/isolamento & purificação , Retículo Sarcoplasmático/enzimologia , Triterpenos/isolamento & purificação
8.
J Ethnopharmacol ; 231: 302-310, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30342194

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ribes diacanthum Pall (RDP), a folk medicine, has been widely used in Mongolia to treat urinary system diseases. AIM OF THE STUDY: To investigate the effectiveness of RDP on unilateral ureteral obstruction (UUO)-induced renal interstitial fibrosis and the underlying mechanisms. MATERIALS AND METHODS: A total of 60 mice were randomly divided into six groups: sham group, sham plus RDP (40 mg/kg) group, UUO model group, and UUO model plus RDP (10, 20 or 40 mg/kg) groups. After surgery, aqueous extract of RDP were administrated intragastrically (i.g) daily for a week and ipsilateral kidneys were collected seven days after surgery. Levels of blood urea nitrogen (BUN) and serum creatinine (Scr) were detected to reflect the kidney injury. Hematoxylin & eosin and Masson's trichrome staining were used to evaluate the kidney morphological changes and fibrosis, respectively. ELISA was used to examine the levels of pro-inflammatory cytokines. Immunohistochemistry, western blot and PCR were used to examine the expression levels of key proteins involved in transforming growth factor (TGF-ß)/Smad and mitogen-activated protein kinase (MAPK) signaling pathways. RESULTS: RDP treatment attenuates the level of BUN and kidney fibrosis in UUO mice, decreases the expressions of interleukin-6, tumor necrosis factor-α, Interleukin-1α, TGF-ß1, monocyte chemotactic protein-1, α-smooth muscle actin, collagen I, fibronectin, and vimentin, while increases the expressions of E-cadherin and hepatocyte growth factor. Moreover, RDP administration significantly decreases the levels of p-Smad2/3, p-ERK1/2, p-p38 and p-JNK, while increases the expression level of Smad7 in UUO models. CONCLUSION: These data demonstrate that RDP ameliorates renal fibrosis through TGF-ß/Smad and MAPK pathways in a UUO mouse model.


Assuntos
Citocinas/metabolismo , Nefropatias/metabolismo , Extratos Vegetais/farmacologia , Ribes , Obstrução Ureteral/metabolismo , Animais , Linhagem Celular , Citocinas/genética , Fibrose , Rim/patologia , Nefropatias/tratamento farmacológico , Nefropatias/etiologia , Masculino , Camundongos Endogâmicos ICR , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fitoterapia , Componentes Aéreos da Planta , Extratos Vegetais/uso terapêutico , Ratos , Transdução de Sinais/efeitos dos fármacos , Obstrução Ureteral/complicações , Obstrução Ureteral/tratamento farmacológico
9.
Virus Genes ; 54(6): 746-755, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30229544

RESUMO

Japanese encephalitis is a zoonotic, mosquito-borne, infectious disease caused by Japanese encephalitis virus (JEV), which is prevalent in China. At present, there are no specific drugs or therapies for JEV infection, which can only be treated symptomatically. Lentivirus-mediated RNA interference (RNAi) is a highly efficient method to silence target genes. In this study, two lentiviral shRNA, LV-C and LV-NS5, targeting the conserved viral gene sequences were used to inhibit different JEV genotypes strains in BHK21 cells and mice. The results showed that LV-C significantly inhibited JEV genotype I and genotype III strains in cells and mice. Quantitative RT-PCR analysis showed that JEV mRNA were reduced by 83.2-90.9% in cells by LV-C and that flow cytometry analysis confirmed the inhibitory activity of LV-C. The viral titers were reduced by about 1000-fold in cells and the brains of suckling mice by LV-C, and the pretreatment of LV-C protected 60-80% of mice against JEV-induced lethality. The inhibitory activities of LV-NS5 in cells and mice were weaker than those of LV-C. These results indicate that RNAi targeting of the two conserved viral gene sequences had significantly suppressed the replication of different JEV genotypes strains in vitro and in vivo, highlighting the feasibility of RNAi targeting of conserved viral gene sequences for controlling JEV infection.


Assuntos
Vírus da Encefalite Japonesa (Espécie)/genética , Encefalite Japonesa/virologia , Genes Virais , Genótipo , Interferência de RNA , Animais , Sequência Conservada , Cricetinae , Encefalite Japonesa/mortalidade , Regulação Viral da Expressão Gênica , Camundongos , RNA Interferente Pequeno/genética , Ensaio de Placa Viral , Replicação Viral
10.
J Nat Prod ; 81(4): 913-917, 2018 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-29469570

RESUMO

Two new acylated ß-hydroxynitrile glycosides, ribemansides A (1) and B (2), were isolated from the aerial parts of Ribes manshuricum. Their structures were elucidated by comprehensive spectroscopic analysis. Ribemansides A and B inhibited transforming growth factor ß1 (TGF-ß1)-induced expression of α-smooth muscle actin, fibronectin release, and changes in cell morphology in the human proximal tubular epithelial cell line (human kidney-2, HK-2). Further biological evaluation demonstrated that both 1 and 2 inhibit the activity of canonical transient receptor potential cation channel 6 (TRPC6), with IC50 values of 24.5 and 25.6 µM, respectively. The antifibrogenic effect of these compounds appears to be mediated through TRPC6 inhibition, since the TRPC6 inhibitor, SAR7334, also suppressed TGF-ß1-induced fibrogenesis in HK-2 cells.


Assuntos
Glicosídeos/farmacologia , Extratos Vegetais/farmacologia , Ribes/química , Canal de Cátion TRPC6/antagonistas & inibidores , Fator de Crescimento Transformador beta1/metabolismo , Actinas/metabolismo , Células Cultivadas , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Fibronectinas/metabolismo , Glicosídeos/química , Humanos , Extratos Vegetais/química
11.
Mycologia ; 107(3): 505-11, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25724995

RESUMO

A new species of Meliolinites (fossil Meliolaceae), M. buxi sp. nov., is reported from the Oligocene Ningming Formation of Guangxi, South China. The fungus has hyphopodia characteristics of extant Meliolaceae, such as thick-walled, branching hyphae with appressoria and phialides. However, these fossils entirely lack mycelial or perithecial setae and have only a few phialides, thereby distinguishing the new species from most known species. The fungus was discovered on the adaxial and abaxial cuticles of several fossilized Buxus leaves. Thickening and twisting of cell walls in the Buxus leaf cuticle, along with the parasitic feeding strategy of the extant Meliolaceae, suggest that a parasitic interaction between Buxus and M. buxi seems feasible. The distribution of modern Meliolaceae suggests that they live in warm, humid subtropical-tropical climates. It is possible that the presence of M. buxi indicates a similar climatic condition. The co-occurrence of large-leaf Buxus and floristic comparisons of the Ningming assemblage also corroborate this conclusion.


Assuntos
Ascomicetos/isolamento & purificação , Buxus/microbiologia , Fósseis/anatomia & histologia , Ascomicetos/classificação , Ascomicetos/crescimento & desenvolvimento , China , Hifas/classificação , Hifas/crescimento & desenvolvimento , Hifas/isolamento & purificação , Folhas de Planta/microbiologia
12.
Biocell ; 35(3): 71-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22423483

RESUMO

Apigenin, a nonmutagenic flavonoid, has been shown to possess free radical scavenging activities, anticarcinogenic properties, antioxidant and anti-inflammatory effects. Recently, apigenin was reported to cause gastric relaxation in murine. To assess possible effects of apigenin on migration of bladder smooth muscle (SM) cell, we isolated SM cells from peri-cancer tissue of human bladder and established a cell model that was capable to overexpress transiently MEKK1 (MEK kinase 1). Results showed that overexpression of active human MEKK1 by adenoviruses infection induced migration of human bladder smooth muscle (hBSM) cells and phosphorylation of MAPKs, ERK, JNK and p38, which are the downstream molecules of MEKK1. Then, hBSM cell overexpressing MEKK1 were exposed to apigenin (50 microM). Our data indicated that apigenin inhibited significantly activation/phosphorylation of MAPKs and migration of hBSM cells induced by MEKK1 overexpression. Besides, apigenin inhibited actin polymerization, which underlines muscle contraction and cell migration. The results suggest that apigenin inhibits activation of MAPKs and thereby the cell migration. The mechanism might be that apigenin blocks signal transmission from MEKK1 to MAPKs.


Assuntos
Apigenina/farmacologia , Movimento Celular/efeitos dos fármacos , MAP Quinase Quinase Quinase 1/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/metabolismo , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo , Adenoviridae/genética , Animais , Células Cultivadas , Humanos , Immunoblotting , MAP Quinase Quinase Quinase 1/genética , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Bexiga Urinária/citologia
13.
Zhong Yao Cai ; 30(9): 1143-5, 2007 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-18236762

RESUMO

OBJECTIVE: To study the extract process of Cyclic adenosinemonophosphate (cAMP) in Ziziphus jujuba. METHODS: CAMP was extracted with water, separated and purificated by ion exchange and silica gel G column chromatography. RESULTS: Thin layer chromatography (TLC) of the extracts and control cAMP showed the same Rf 0.75; The UV-absorption of the extracts and control cAMP had maximal absorb peak at 260 nm and the least absorb value at 230 nm; Infra-red spectrum of the extracts was indistinguishable from that of control cAMP; Retention time of the extracts by high-performance liquid chromatography (HPLC) determinate was 5.237 minute,unsettled impurity peak,content was 97%. Control cAMP was 5.350 minute,their retention time were of little difference. CONCLUSION: Chemistry structure of this extract with that of control cAMP is the same.


Assuntos
AMP Cíclico/isolamento & purificação , Frutas/química , Plantas Medicinais/química , Ziziphus/química , Cromatografia Líquida de Alta Pressão , AMP Cíclico/química , Géis , Resinas de Troca Iônica , Estrutura Molecular , Plantas Comestíveis/química , Tecnologia Farmacêutica/métodos
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