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1.
Opt Express ; 32(10): 16970-16982, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38858891

ABSTRACT

Laser-induced plasma micromachining (LIPMM) is an advanced technology that utilizes the plasma generated from laser breakdown to remove material, thereby facilitating the fabrication of microstructures. This paper explores the use of LIPMM on 304 stainless steel surfaces parallel to the laser beam in different solutions, focusing on the impact of the liquid environment on the machining process. It presents a theoretical analysis of the material removal mechanisms unique to this orientation and experimentally investigates how water, a salt solution, and ethanol affect plasma shockwave characteristics. Notably, the plasma shockwave in the salt solution demonstrates the most significant peak pressure and energy, enhancing the micromachining efficiency. These findings suggest that varying the liquid environment can significantly influence LIPMM's effectiveness, offering potential improvements in precision and control. This study broadens the understanding of LIPMM applications, especially in orientations not commonly explored, and opens new possibilities for advanced micromachining techniques in various industrial applications.

2.
J Photochem Photobiol B ; 256: 112937, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38743989

ABSTRACT

As the outermost layer of the human body, the skin suffers from various external factors especially light damage, among which ultraviolet B (UVB) irradiation is common and possesses a relatively high biological damage capacity. Pyroptosis is a newly discovered type of programmed cell death, which can induce cell rupture and induce local inflammatory response. However, the molecular mechanisms of pyroptosis in photodamaged skin is poorly understood. Baicalin, a flavonoid extracted from the desiccated root of Scutellaria baicalensis Georgi (Huang Qin). Despite its antioxidant abilities, whether baicalin protects skin by attenuating UVB-induced pyroptosis remains unclear, which was the aim of this study. The UVB-induced acute skin damage model was established by using human immortalized keratinocytes (HaCaT cells) and Kunming (KM) strain mice. The protective dose selection for baicalin is 50 µM in vitro and 100 mg/kg in vivo. In in vitro study, UVB irradiation significantly decreased cell viability, increased cell death and oxidative stress in HaCaT cells, while pretreatment with baicalin improved these phenomena. Furthermore, the baicalin pretreatment notably suppressed nuclear factor kappa B (NF-κB) translocation, the NLRP3 inflammasome activation and gasdermin D (GSDMD) maturation, thus effectively attenuating UVB-induced pyroptosis. In in vivo study, the baicalin pretreatment mitigated epidermal hyperplasia, collagen fiber fragmentation, oxidative stress and pyroptosis in UVB-irradiated mouse skin. In a nutshell, this study suggests that baicalin could be a potential protective agent to attenuate acute skin damage induced by UVB irradiation through decreasing oxidative stress and suppressing NF-κB/NLRP3/GSDMD-involved pyroptosis.


Subject(s)
Flavonoids , NF-kappa B , NLR Family, Pyrin Domain-Containing 3 Protein , Pyroptosis , Skin , Ultraviolet Rays , Pyroptosis/drug effects , Pyroptosis/radiation effects , Flavonoids/pharmacology , Flavonoids/chemistry , Animals , Humans , Mice , Skin/radiation effects , Skin/drug effects , Skin/pathology , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , NF-kappa B/metabolism , Oxidative Stress/drug effects , Oxidative Stress/radiation effects , Keratinocytes/drug effects , Keratinocytes/radiation effects , Keratinocytes/metabolism , HaCaT Cells , Cell Survival/drug effects , Cell Survival/radiation effects , Phosphate-Binding Proteins/metabolism , Inflammasomes/metabolism , Cell Line
3.
PeerJ ; 12: e16709, 2024.
Article in English | MEDLINE | ID: mdl-38188141

ABSTRACT

Background: Sepsis and sepsis-associated acute kidney injury (SA-AKI) pose significant global health challenges, necessitating the development of innovative therapeutic strategies. Dysregulated protein expression has been implicated in the initiation and progression of sepsis and SA-AKI. Identifying potential protein targets and modulating their expression is crucial for exploring alternative therapies. Method: We established an SA-AKI rat model using cecum ligation perforation (CLP) and employed differential proteomic techniques to identify protein expression variations in kidney tissues. Aldose reductase (AKR1B1) emerged as a promising target. The SA-AKI rat model received treatment with the aldose reductase inhibitor (ARI), epalrestat. Blood urea nitrogen (BUN) and creatinine (CRE) levels, as well as IL-1ß, IL-6 and TNF-α levels in the serum and kidney tissues, were monitored. Hematoxylin-eosin (H-E) staining and a pathological damage scoring scale assessed renal tissue damage, while protein blotting determined PKC (protein kinase C)/NF-κB pathway protein expression. Result: Differential proteomics revealed significant downregulation of seven proteins and upregulation of 17 proteins in the SA-AKI rat model renal tissues. AKR1B1 protein expression was notably elevated, confirmed by Western blot. ARI prophylactic administration and ARI treatment groups exhibited reduced renal injury, low BUN and CRE levels and decreased IL-1ß, IL-6 and TNF-α levels compared to the CLP group. These changes were statistically significant (P < 0.05). AKR1B1, PKC-α, and NF-κB protein expression levels were also lowered in the ARI prophylactic administration and ARI treatment groups compared to the CLP group (P < 0.05). Conclusions: Epalrestat appeared to inhibit the PKC/NF-κB inflammatory pathway by inhibiting AKR1B1, resulting in reduced inflammatory cytokine levels in renal tissues and blood. This mitigated renal tissue injuries and improved the systemic inflammatory response in the severe sepsis rat model. Consequently, AKR1B1 holds promise as a target for treating sepsis-associated acute kidney injuries.


Subject(s)
Acute Kidney Injury , Sepsis , Animals , Rats , Acute Kidney Injury/drug therapy , Aldehyde Reductase , Interleukin-6 , NF-kappa B , Proteomics , Sepsis/complications , Tumor Necrosis Factor-alpha
4.
Article in English | MEDLINE | ID: mdl-38064630

ABSTRACT

Objective: To observe the effects of traditional Chinese medicine (TCM) five-element music therapy combined with mirtazapine on depression and limb function recovery after ischemic stroke. Methods: A total of 110 patients treated in the Departments of Geriatrics, Cardiology, and Psychology of three hospitals in Qinhuangdao City, Hebei Province, China from October 2022 to August 2023 were selected. Based on the scores of 24-item Hamilton Depression Scale (HAMD-24), Barthel (BL) index, and National Institute of Health Stroke Scale (NIHSS) before enrollment, the patients were randomly divided into control group (n = 58) and experimental group (n = 52). The patients in control group were treated with limb rehabilitation, while those in experimental group underwent limb rehabilitation combined with five-element music therapy and mirtazapine. Results: After 12 weeks of treatment and observation, 11 patients in control group and 9 patients in experimental group withdrew from this trail. As for the proportions of score changes, experimental group had higher decline proportions of HAMD-24 score and NIHSS score as well as an increased proportion of BL index score than control group, which were 43.97%, 69.32%, and 44.12%, respectively. Conclusion: TCM five-element music therapy combined with mirtazapine significantly improves depression and limb function recovery after ischemic stroke.

5.
BMC Cardiovasc Disord ; 23(1): 191, 2023 04 12.
Article in English | MEDLINE | ID: mdl-37046189

ABSTRACT

We explored the effect of thrombin on human aortic smooth muscle cells (HASMCs) and further analyzed its role in the pathogenesis of atherosclerosis (AS). Thrombin-induced differentially expressed genes (DEGs) in HASMCs were identified by analyzing expression profiles from the GEO. Subsequently, enrichment analysis, GSEA, PPI network, and gene-microRNAs networks were interrogated to identify hub genes and associated pathways. Enrichment analysis results indicated that thrombin causes HASMCs to secrete various pro-inflammatory cytokines and chemokines, exacerbating local inflammatory response in AS. Moreover, we identified 9 HUB genes in the PPI network, which are closely related to the inflammatory response and the promotion of the cell cycle. Additionally, we found that thrombin inhibits lipid metabolism and autophagy of HASMCs, potentially contributing to smooth muscle-derived foam cell formation. Our study deepens a mechanistic understanding of the effect of thrombin on HASMCs and provides new insight into treating AS.


Subject(s)
Atherosclerosis , Transcriptome , Humans , Thrombin/genetics , Thrombin/metabolism , Thrombin/pharmacology , Atherosclerosis/pathology , Myocytes, Smooth Muscle/metabolism , Muscle, Smooth/metabolism , Muscle, Smooth/pathology
6.
Adv Clin Exp Med ; 32(6): 655-666, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36881362

ABSTRACT

BACKGROUND: During ischemic stroke treatment, cerebral ischemia/reperfusion (I/R) injury results in neuronal cell death and neurological dysfunctions in brain. Previous studies indicate that basic helix-loop-helix family member e40 (BHLHE40) exerts protective effects on the pathology of neurogenic diseases. However, the protective function of BHLHE40 in I/R is unclear. OBJECTIVES: This study aimed to explore the expression, role and potential mechanism of BHLHE40 after ischemia. MATERIAL AND METHODS: We established models of I/R injury in rats and of oxygen-glucose deprivation/reoxygenation (OGD/R) in primary hippocampal neurons. Nissl and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was performed to detect neuronal injury and apoptosis. Immunofluorescence was used to detect BHLHE40 expression. Cell viability and cell damage measurements were conducted using Cell Counting Kit-8 (CCK-8) assay and lactate dehydrogenase (LDH) assay. The regulation of BHLHE40 to pleckstrin homology-like domain family A, member 1 (PHLDA1) was assessed using the dual-luciferase assay and chromatin immunoprecipitation (ChIP) assay. RESULTS: Cerebral I/R rats exhibited severe neuronal loss and apoptosis in hippocampal cornu Ammonis 1 (CA1) region, accompanied by downregulated BHLHE40 expression at both mRNA and protein levels, indicating that BHLHE40 may regulate the apoptosis of hippocampal neurons. The function of BHLHE40 in neuronal apoptosis during cerebral I/R was further explored by establishing an OGD/R model in vitro. Low expression of BHLHE40 was also observed in neurons treated with OGD/R. The OGD/R administration inhibited cell viability and enhanced cell apoptosis in hippocampal neurons, whereas BHLHE40 overexpression reversed those changes. Mechanistically, we demonstrated that BHLHE40 could repress PHLDA1 transcription by binding to PHLDA1 promoter. The PHLDA1 is a facilitator of neuronal damage in brain I/R injury and its upregulation reversed the effects caused by BHLHE40 overexpression in vitro. CONCLUSIONS: The transcription factor BHLHE40 may protect against brain I/R injury through repressing cell damage via regulating PHLDA1 transcription. Thus, BHLHE40 may be a candidate gene for further study of molecular or therapeutic targets for I/R.


Subject(s)
Brain Ischemia , Reperfusion Injury , Rats , Animals , Apoptosis/genetics , Reperfusion Injury/genetics , Reperfusion Injury/prevention & control , Reperfusion Injury/metabolism , Brain Ischemia/genetics , Up-Regulation , Oxygen/metabolism , Glucose
7.
J Inflamm (Lond) ; 20(1): 5, 2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36737780

ABSTRACT

Acute lung injury is a major cause of death in sepsis. Tofacitinib (TOFA), a JAK inhibitor, has anti-inflammatory activity in autoimmune diseases, but its role in acute lung injury in sepsis remains unclear. The purpose of this study is to establish a septic rat model by cecal ligation and perforation, and to evaluate the effect of tofacitinib on the survival rate of septic rat model and its role in acute lung injury in septic rats and the possible mechanism of action. In this study, TOFA (1 mg/kg, 3 mg/kg, 10 mg/kg) was used to observe the survival rate of septic rats. It was found that TOFA (10 mg/kg) significantly improved the survival rate of septic rats. We selected TOFA (10 mg/kg) and focused on the protective effect of TOFA on acute lung injury. The results confirmed that TOFA significantly inhibited the expression of TNF-α, IL-1ß, IL-6 and IFN-γ inflammatory factors, reduced the W/D weight ratio of septic lung tissue, and significantly improved lung histopathological damage. These results may be related to the inhibitory effect of TOFA on JAK-STAT/NF-κ B signaling pathway. In conclusion, for the first time, we found that TOFA has a protective effect against sepsis-induced acute lung injury, and it may be a promising drug for the treatment of acute lung injury in sepsis.

8.
Eur J Med Res ; 27(1): 206, 2022 Oct 17.
Article in English | MEDLINE | ID: mdl-36253831

ABSTRACT

Secukinumab is a specific neutralizing antibody for IL-17A. At present, numerous studies have confirmed the important role of IL-17A in sepsis, but the role of secukinumab in sepsis has not been studied. The present study explored the protective effect and underlying mechanism of secukinumab in severe sepsis model rats. We established a severe sepsis rat model using cecal ligation and puncture (CLP). The optimal dose of secukinumab was determined by observing the 7-day survival rate of severe sepsis model rats. The expression levels of TNF-α, IL-6, and IL-17A in plasma and lung tissue were determined by enzyme-linked immunosorbent assay. The degree of pathological damage to lung tissue was evaluated by hematoxylin-eosin (H-E) staining and pathological damage scale. The expressions of IKBα/NFκB pathway proteins and downstream-related inflammatory factors were detected by western blotting and real-time quantitative polymerase chain reaction (RT-qPCR). Our results show that high-dose secukinumab can inhibit the activation of the IKBα/NFκB inflammatory pathway by neutralizing IL-17A and reducing the gene expression of pathway-related inflammatory cytokines, thereby reducing the levels of inflammatory cytokines in lung tissue and plasma, thereby reducing the damage of lung tissue in severe sepsis model rats and improving the systemic inflammatory response.


Subject(s)
Interleukin-17 , Sepsis , Animals , Antibodies, Monoclonal, Humanized , Antibodies, Neutralizing/pharmacology , Antibodies, Neutralizing/therapeutic use , Cytokines/metabolism , Disease Models, Animal , Eosine Yellowish-(YS) , Hematoxylin , Interleukin-17/genetics , Interleukin-6 , Rats , Sepsis/drug therapy , Signal Transduction , Tumor Necrosis Factor-alpha
9.
BMC Musculoskelet Disord ; 23(1): 507, 2022 May 28.
Article in English | MEDLINE | ID: mdl-35643440

ABSTRACT

BACKGROUND: Pain catastrophizing in preoperative total knee arthroplasty (TKA) patients is associated with several poorly characterised factors in the literature. This study investigated the current state and associated factors of preoperative pain catastrophizing in patients undergoing TKA. METHODS: This descriptive cross-sectional study was conducted at the orthopedics ward of two tertiary hospitals in Lanzhou, China. Pain catastrophizing was measured using the Chinese versions of the Pain Catastrophizing Scale, Short Form-36 (physical function domain), Numerical Rating Scale, Oxford Knee Score, Hospital Anxiety and Depression Scale, and Life Orientation Test-Revised. RESULTS: The study included 360 participants. Preoperative TKA pain catastrophizing in all patients was high, with a mean score of 24.92 (SD: 12.38). The stepwise multiple linear regression analysis revealed anxiety (ß = 0.548, P < 0.01), education level (ß = - 0.179, P < 0.01), physical function (ß = - 0.156, P < 0.01), and pain intensity during activity (ß = 0.105, P = 0.015) as associated factors for pain catastrophizing, possibly explaining 51.2% of the total variation (F = 95.149, P < 0.01). CONCLUSION: Anxiety was the most relevant factor for pain catastrophizing in patients with preoperative TKA. Lower education levels, poor physical function, and stronger pain intensity during the activity were also associated with pain catastrophizing.


Subject(s)
Arthroplasty, Replacement, Knee , Osteoarthritis, Knee , Arthroplasty, Replacement, Knee/adverse effects , Catastrophization , China/epidemiology , Cross-Sectional Studies , Humans , Osteoarthritis, Knee/complications , Pain/surgery
10.
Adv Sci (Weinh) ; 9(21): e2201446, 2022 07.
Article in English | MEDLINE | ID: mdl-35644043

ABSTRACT

The adjustable conductance of a two-terminal memristor in a crossbar array can facilitate vector-matrix multiplication in one step, making the memristor a promising synapse for efficiently implementing neuromorphic computing. To achieve controllable and gradual switching of multi-level conductance, important for neuromorphic computing, a theoretical design of a superlattice-like (SLL) structure switching layer for the multi-level memristor is proposed and validated, refining the growth of conductive filaments (CFs) and preventing CFs from the abrupt formation and rupture. Ti/(HfOx /AlOy )SLL /TiN memristors are shown with transmission electron microscopy , X-ray photoelectron spectroscopy , and ab initio calculation findings corroborate the SLL structure of HfOx /AlOy film. The optimized SLL memristor achieves outstanding conductance modulation performance with linearly synaptic weight update (nonlinear factor α = 1.06), and the convolutional neural network based on the SLL memristive synapse improves the handwritten digit recognition accuracy to 94.95%. Meanwhile, this improved synaptic device has a fast operating speed (30 ns), a long data retention time (≥ 104 s at 85 â„ƒ), scalability, and CMOS process compatibility. Finally, its physical nature is explored and the CF evolution process is characterized using nudged elastic band calculations and the conduction mechanism fitting. In this work, as an example the HfOx /AlOy SLL memristor provides a design viewpoint and optimization strategy for neuromorphic computing.


Subject(s)
Electric Conductivity , Humans , Neural Networks, Computer , Synapses
11.
Adv Sci (Weinh) ; 9(15): e2200036, 2022 May.
Article in English | MEDLINE | ID: mdl-35343097

ABSTRACT

The rise of emerging technologies such as Big Data, the Internet of Things, and artificial intelligence, which requires efficient power schemes, is driving brainstorming in data computing and storage technologies. In this study, merely relying on the fundamental structure of two memristors and a resistor, arbitrary Boolean logic can be reconfigured and calculated in two steps, while no additional voltage sources are needed beyond "±VP " and 0, and all state reversals are based on memristor set switching. Utilizing the proposed logic scheme in an elegant form of unity structure and minimum cost, the implementation of a 1-bit adder is demonstrated economically, and a promising circuit scheme for the N-bit adder is exhibited. Some critical issues including the crosstalk problem, energy consumption, and peripheral circuits are further simulated and discussed. Compared with existing works on memristive logic, such methods support building a memristor-based digital in-memory calculation system with high functional reconfigurability, simple voltage sources, and low power and area consumption.

13.
Langmuir ; 37(49): 14314-14322, 2021 Dec 14.
Article in English | MEDLINE | ID: mdl-34865489

ABSTRACT

Inspired by natural creatures, superhydrophobic surfaces with various adhesion behaviors have attracted significant scientific interest. In this study, by controlling the laser fluence, the scanning times, and the subsequent cleaning method, microcolumn arrays with different morphologies were fabricated on 304 stainless-steel surfaces using picosecond laser direct writing. To achieve wettability transition, the laser-processed samples were then subjected to heat treatments (120 °C) in air and in a low vacuum environment (6 kPa). The results show that after heat treatment in different environments and with various time lengths, the laser-processed surfaces become hydrophobic surfaces with different adhesion properties. It is worth noting that while surfaces heat-treated in air exhibit weak wettability transition potential and high adhesion, the surfaces heat-treated in a low vacuum environment present superhydrophobic and low adhesion properties with a minimum sliding angle of about 3.14°. Moreover, the low-vacuum heat-treated surfaces retain good superhydrophobic properties after 1 month of observation as well as an abrasion test. These transitions in hydrophobic behavior and adhesion properties may be mainly attributed to the heat treatment-induced (in the air or in a low vacuum environment) redistribution of surface compounds and the microstructure-induced alternation of the solid-liquid contact state. By controlling the laser processing parameters and the heat treatment time and environment, stable wettability transition and flexible adhesion control of stainless steel can be easily achieved.

14.
EMBO Rep ; 22(9): e52252, 2021 09 06.
Article in English | MEDLINE | ID: mdl-34288348

ABSTRACT

Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (Mtb) that places a heavy strain on public health. Host susceptibility to Mtb is modulated by macrophages, which regulate the balance between cell apoptosis and necrosis. However, the role of molecular switches that modulate apoptosis and necrosis during Mtb infection remains unclear. Here, we show that Mtb-susceptible mice and TB patients have relatively low miR-342-3p expression, while mice with miR-342-3p overexpression are more resistant to Mtb. We demonstrate that the miR-342-3p/SOCS6 axis regulates anti-Mtb immunity by increasing the production of inflammatory cytokines and chemokines. Most importantly, the miR-342-3p/SOCS6 axis participates in the switching between Mtb-induced apoptosis and necrosis through A20-mediated K48-linked ubiquitination and RIPK3 degradation. Our findings reveal several strategies by which the host innate immune system controls intracellular Mtb growth via the miRNA-mRNA network and pave the way for host-directed therapies targeting these pathways.


Subject(s)
MicroRNAs , Mycobacterium tuberculosis , Tuberculosis , Animals , Cell Death , Humans , Inflammation/genetics , Mice , MicroRNAs/genetics , Mycobacterium tuberculosis/genetics , Suppressor of Cytokine Signaling Proteins , Tuberculosis/genetics
15.
Chest ; 160(5): 1660-1669, 2021 11.
Article in English | MEDLINE | ID: mdl-34023318

ABSTRACT

BACKGROUND: Systemic corticosteroids for the treatment of COPD exacerbations decrease treatment failure and shorten the length of hospitalization. However, the optimal dose is unclear. RESEARCH QUESTION: Is personalized-dose corticosteroid administered according to a dosing scale more effective than fixed-dose corticosteroid administration in hospitalized patients with COPD with exacerbations? STUDY DESIGN AND METHODS: This was a prospective, randomized, open-label trial. In-hospital patients with COPD with exacerbations were randomly assigned at a 1:1 ratio to either the fixed-dose group (receiving the equivalent of 40 mg of prednisolone) or the personalized-dose group for 5 days. The primary end point was a composite measure of treatment failure that included in-hospital treatment failure and medium-term (postdischarge) failure. Secondary end points were length of stay and cost. RESULTS: A total of 248 patients were randomly assigned to the fixed-dose group (n = 124) or personalized-dose group (n = 124). One patient in each group was not included in the intention-to-treat population because of incorrect initial COPD diagnosis. Failure of therapy occurred in 27.6% in the personalized-dose group, compared with 48.8% in the fixed-dose group (relative risk, 0.40; 95% CI, 0.24-0.68; P = .001). The in-hospital failure of therapy was significantly lower in the personalized-dose group (10.6% vs 24.4%; P = .005), whereas the medium-term failure rate, adverse event rate, hospital length of stay, and costs were similar between the two groups. After treatment failure, a lower additional dose of corticosteroids and a shorter duration of treatment were needed in the personalized-dose group to achieve control of the exacerbation. In the personalized-dose cohort, those receiving 40 mg or less had an average failure rate of 44.4%, compared with 22.9% among those receiving more than 40 mg (P = .027). INTERPRETATION: Personalized dosing of corticosteroids reduces the risk of failure because more patients were provided with a higher initial dose, especially > 60 mg, whereas 40 mg or less was too low in either group. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT02147015; URL: www.clinicaltrials.gov.


Subject(s)
Dose-Response Relationship, Drug , Glucocorticoids , Pulmonary Disease, Chronic Obstructive , Administration, Inhalation , Adrenal Cortex Hormones/administration & dosage , Adrenal Cortex Hormones/adverse effects , Aged , Drug Dosage Calculations , Female , Glucocorticoids/administration & dosage , Glucocorticoids/adverse effects , Humans , Intensive Care Units/statistics & numerical data , Length of Stay/economics , Length of Stay/statistics & numerical data , Male , Outcome and Process Assessment, Health Care , Patient Readmission/statistics & numerical data , Pulmonary Disease, Chronic Obstructive/diagnosis , Pulmonary Disease, Chronic Obstructive/mortality , Pulmonary Disease, Chronic Obstructive/therapy , Symptom Assessment/methods , Symptom Flare Up
16.
iScience ; 24(4): 102293, 2021 Apr 23.
Article in English | MEDLINE | ID: mdl-33723527

ABSTRACT

Recently, COVID-19 caused by the novel coronavirus SARS-CoV-2 has brought great challenges to the world. More and more studies have shown that patients with severe COVID-19 may suffer from cytokine storm syndrome; however, there are few studies on its pathogenesis. Here we demonstrated that SARS-CoV-2 coding protein open reading frame 8 (ORF8) acted as a contributing factor to cytokine storm during COVID-19 infection. ORF8 could activate IL-17 signaling pathway and promote the expression of pro-inflammatory factors. Moreover, we demonstrated that treatment of IL17RA antibody protected mice from ORF8-induced inflammation. Our findings are helpful to understand the pathogenesis of cytokine storm caused by SARS-CoV-2 and provide a potential target for the development of COVID-19 therapeutic drugs.

17.
Opt Express ; 26(15): 18998-19008, 2018 Jul 23.
Article in English | MEDLINE | ID: mdl-30114160

ABSTRACT

Ordered hierarchical structures were fabricated on a stainless steel surface using a single picosecond laser for highly controllable dimensions. Picosecond laser induced periodic structures were firstly used to create large-scale nano-structures with a period of ~450 nm. Subsequently, laser direct writing, by simply changing process parameters was employed to create micro squared structures with 19 µm width, 19 µm interval and 3-7.5 µm depth on the previously created nano-structures. As a result, micro squared structures covered by uniform nano-structures, similar to examples present in nature, were successfully fabricated. Additionally, the wettability of the created hierarchical structures was analyzed. The results demonstrated that the combination of both micro- and nano-structures allowed to tune the wetting behavior, presenting a great potential for wettability applications.

18.
Opt Express ; 26(5): 6325-6330, 2018 Mar 05.
Article in English | MEDLINE | ID: mdl-29529824

ABSTRACT

The formation of periodic structures on stainless steel under linearly polarized multi-burst picosecond laser pulses irradiation was experimentally investigated. The resulting structures were characterized by scanning electron microscopy (SEM) analysis. This analysis of images revealed four distinctive (quasi-) periodic structures depending on the laser irradiation parameters, i.e., LSFLs, HSFLs, micro-grooves and nano-holes. It is demonstrated that the multi-burst picosecond pulses technique is capable of fabricating periodic structures with different scales and shapes.

19.
Structure ; 23(12): 2224-2233, 2015 Dec 01.
Article in English | MEDLINE | ID: mdl-26602185

ABSTRACT

Pin1 is a modular peptidyl-prolyl isomerase specific for phosphorylated Ser/Thr-Pro (pS/T-P) motifs, typically within intrinsically disordered regions of signaling proteins. Pin1 consists of two flexibly linked domains: an N-terminal WW domain for substrate binding and a larger C-terminal peptidyl-prolyl isomerase (PPIase) domain. Previous studies showed that binding of phosphopeptide substrates to Pin1 could alter Pin1 interdomain contact, strengthening or weakening it depending on the substrate sequence. Thus, substrate-induced changes in interdomain contact may act as a trigger within the Pin1 mechanism. Here, we investigate this possibility via nuclear magnetic resonance studies of several Pin1 mutants. Our findings provide new mechanistic insights for those substrates that reduce interdomain contact. Specifically, the reduced interdomain contact can allosterically enhance PPIase activity relative to that when the contact is sustained. These findings suggest Pin1 interdomain contact can negatively regulate its activity.


Subject(s)
Peptidylprolyl Isomerase/chemistry , Allosteric Regulation , Amino Acid Sequence , Humans , Molecular Sequence Data , Mutation , NIMA-Interacting Peptidylprolyl Isomerase , Peptidylprolyl Isomerase/genetics , Peptidylprolyl Isomerase/metabolism , Protein Structure, Tertiary
20.
Proc Natl Acad Sci U S A ; 112(15): E1908-15, 2015 Apr 14.
Article in English | MEDLINE | ID: mdl-25825747

ABSTRACT

In bacteria, certain shape-sensing proteins localize to differently curved membranes. During sporulation in Bacillus subtilis, the only convex (positively curved) surface in the cell is the forespore, an approximately spherical internal organelle. Previously, we demonstrated that SpoVM localizes to the forespore by preferentially adsorbing onto slightly convex membranes. Here, we used NMR and molecular dynamics simulations of SpoVM and a localization mutant (SpoVM(P9A)) to reveal that SpoVM's atypical amphipathic α-helix inserts deeply into the membrane and interacts extensively with acyl chains to sense packing differences in differently curved membranes. Based on binding to spherical supported lipid bilayers and Monte Carlo simulations, we hypothesize that SpoVM's membrane insertion, along with potential cooperative interactions with other SpoVM molecules in the lipid bilayer, drives its preferential localization onto slightly convex membranes. Such a mechanism, which is distinct from that used by high curvature-sensing proteins, may be widely conserved for the localization of proteins onto the surface of cellular organelles.


Subject(s)
Bacillus subtilis/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/metabolism , Cell Membrane/metabolism , Protein Structure, Secondary , Bacillus subtilis/genetics , Bacterial Proteins/genetics , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Lipid Bilayers/metabolism , Magnetic Resonance Spectroscopy , Microscopy, Fluorescence , Molecular Dynamics Simulation , Monte Carlo Method , Mutation , Protein Binding
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