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1.
Artigo em Inglês | MEDLINE | ID: mdl-38416285

RESUMO

OBJECTIVE: Myocardial ischemia/reperfusion (I/R) injury can cause severe cardiac damage. Aloperine is a quinolizidine alkaloid found in the leaves and seeds of Sophora alopecuroides L. It has been recognized that aloperine has organ-protective properties; however, its role in cardioprotection is poorly characterized. This study aimed to evaluate the cardioprotective effects of aloperine against myocardial I/R injury in vivo. METHODS: Adult male Sprague‒Dawley rats were randomly divided into sham-operated, control, and aloperine groups. All rats except for the sham-operated rats were subjected to 45 min of myocardial ischemia (by left anterior descending ligation) followed by 3 h of reperfusion. Aloperine (10 mg/kg) was given intravenously at the onset of reperfusion. The cardioprotective effects of aloperine were evaluated by determining infarct size, hemodynamics, histological changes, cardiac biomarkers, and cardiac apoptosis. RESULTS: Aloperine limited infarct size; improved hemodynamics; attenuated myocardial I/R-induced histological deterioration; decreased serum LDH, CK-MB, and α-HBDH levels; and inhibited apoptosis after myocardial I/R injury. Moreover, aloperine stimulated the phosphorylation of ventricular ERK1/2, which is a major module of MAPK signaling pathways. Furthermore, aloperine increased the ventricular expression levels of ß-catenin. Pharmacological inhibition of ERK1/2 diminished aloperine-induced cardioprotection and blocked ERK1/2/ß-catenin signaling. CONCLUSIONS: These data support the cardioprotective effect of aloperine against myocardial I/R injury, which is mediated, at least in part, by the ERK1/2/ß-catenin signaling pathway.

2.
Toxics ; 12(2)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38393231

RESUMO

BACKGROUND: The association between specific chemical components of PM2.5 and depression remains largely unknown. METHODS: We conducted a time-stratified case-crossover analysis with a distributed lag nonlinear model (DLNM) to evaluate the relationship of PM2.5 and its chemical components, including black carbon (BC), organic matter (OM), sulfate (SO42-), nitrate (NO3-), and ammonium (NH4+), with the depression incidence. Daily depression outpatients were enrolled from Huizhou, Shenzhen, and Zhaoqing. RESULTS: Among 247,281 outpatients, we found the strongest cumulative effects of PM2.5 and its chemical components with the odd ratios (ORs) of 1.607 (95% CI: 1.321, 1.956) and 1.417 (95% CI: 1.245, 1.612) at the 50th percentile of PM2.5 and OM at lag 21, respectively. Furthermore, the ORs with SO42- and NH4+ at the 75th percentile on the same lag day were 1.418 (95% CI: 1.247, 1.613) and 1.025 (95% CI: 1.009, 1.140). Relatively stronger associations were observed among females and the elderly. CONCLUSIONS: Our study suggests that PM2.5 and its chemical components might be important risk factors for depression. Reducing PM2.5 emissions, with a particular focus on the major sources of SO42- and OM, might potentially alleviate the burden of depression in South China.

4.
Vaccine ; 42(4): 828-839, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38220489

RESUMO

Porcine epidemic diarrhea virus (PEDV) has caused serious economic losses to the pig husbandry worldwide, and the effects of existing commercialized vaccines are suboptimal. Therefore, research to develop an efficacious vaccine for prevention and control of PEDV is essential. In this study, we designed and produced trimerized proteins of full-length PEDV spike (S) protein, S1 subunit, and a tandem of multiple epitopes of S protein using an efficient mammalian expression vector system in HEK 293F cells. The immunogenicity of two commercial adjuvants, M401 and M103, was also evaluated in mice. Enzyme-linked immunosorbent assays demonstrated that all immunized mice generated highly systemic PEDV S-specific IgG and IgA antibodies. Mice in S/M103-immunized group generated the highest neutralizing antibody titer with 1:96. Compared with control group, the subunit vaccines elicited multifunctional CD3+CD4+ and CD3+CD8+ T cells, B220+CD19+ B cells, and CD3-CD49b+ natural killer cells in the spleen. PEDV S/M103 vaccine, which had the best immune effect, was selected for further evaluation in piglets. Immunization with S/M103 vaccine induced high levels of S-specific IgG, IgA, and neutralizing antibodies, and increased the proliferation of peripheral blood mononuclear cells and the expression levels of interferon-γ and interleukin-4 in peripheral blood of piglets. Virus challenge test results showed significantly lower diarrheal index scores and fecal viral loads, and less pathological damage to the intestines in S/M103-immunized piglets than in controls, indicating that S/M103 provides good protection against the virulent virus challenge. Our findings suggest that trimeric PEDV S/M103 has potential as a clinical vaccine candidate.


Assuntos
Infecções por Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Vacinas Virais , Animais , Suínos , Camundongos , Anticorpos Antivirais , 60470 , Linfócitos T CD8-Positivos , Leucócitos Mononucleares , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/veterinária , Vacinas de Subunidades , Imunoglobulina A , Imunoglobulina G , Glicoproteína da Espícula de Coronavírus , Mamíferos
5.
J Orthop Translat ; 44: 47-59, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38229660

RESUMO

Background: Osteoarthritis (OA) is a chronic degenerative joint disease that primarily affects middle-aged and elderly individuals. The decline in chondrocyte function plays a crucial role in the development of OA. Inflammasome-mediated chondrocyte pyroptosis is implicated in matrix degradation and cartilage degeneration in OA patients. Guanylate binding protein 5 (GBP5), a member of the GTPase family induced by Interferon-γ (IFN-γ), significantly influences cellular inflammatory responses, including intracellular inflammasome activation and cytokine release. However, the role of GBP5 in chondrocyte pyroptosis and OA progression remains unclear. Methods: In this study, we used tumor necrosis factor-α (TNF-α) to induce inflammation and created an OA mouse model with surgically-induced destabilization of the medial meniscus (DMM). We isolated and cultured primary chondrocytes from the knee joints of suckling C57 mice. TNF-α-stimulated primary chondrocytes served as an in vitro model for OA and underwent RNA sequencing. Chondrocytes were transfected with GBP5-overexpression plasmids and small interfering RNA and were subsequently treated with TNF-α. We assessed the expression of cartilage matrix components (COL2A1 and aggrecan), catabolic factors (MMP9 and MMP13), and NLRP3 inflammasome pathway genes (NLRP3, Caspase1, GSDMD, Pro-IL-1ß, and Pro-Caspase1) using RT-qPCR and Western blotting. We analyzed the expression of GBP5, NLRP3, and Caspase1 in the cartilage of DMM-induced post-traumatic OA mice and human OA patients. Immunohistochemistry (IHC) was used to detect the expression of GBP5, NLRP3 and GSDMD in cartilage specimens from OA patients and mouse DMM models. Chondrocyte pyroptosis was assessed using flow cytometry, and the levels of interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) were measured with ELISA. We conducted double luciferase reporter gene and chromatin immunoprecipitation (ChIP) assays to confirm the relationship between IRF1 and GBP5. Results: GBP5 expression increased in TNF-α-induced chondrocytes, as revealed by RNA sequencing. GBP5 inhibited COL2A1 and aggrecan expression while promoting the expression of MMP9, MMP13, NLRP3, Caspase1, GSDMD, Pro-IL-1ß, and Pro-Caspase1. GBP5 expression also increased in the cartilage of DMM-induced post-traumatic OA mice and human OA patients. Knockout of GBP5 reduced chondrocyte injury in OA mice. GBP5 promoted chondrocyte pyroptosis and the production of IL-1ß and IL-18. Additionally, we found that IRF1 bound to the promoter region of GBP5, enhancing its expression. After co-transfected with ad-IRF1 and siGBP5, the expression of pyroptosis-related genes was significantly decreased compared with ad-IRF1 group. Conclusions: The IRF1/GBP5 axis enhances extracellular matrix (ECM) degradation and promotes pyroptosis during OA development, through the NLRP3 inflammasome signaling pathway. The translational potential of this article: This study underscores the significance of the IRF1/GBP5 axis in NLRP3 inflammasome-mediated chondrocyte pyroptosis and osteoarthritic chondrocyte injury. Modulating IRF1 and GBP5 expression could serve as a novel therapeutic target for OA.

6.
Arch Biochem Biophys ; 751: 109827, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38000494

RESUMO

Osteoarthritis (OA) is a common aging-related disease affecting entire joint structures, encompassing articular cartilage and subchondral bone. Although senescence and dysfunction of chondrocytes are considered crucial factors in the occurrence of OA, the exact pathogenesis remains to be investigated. In our study, chondrocytes were incubated with a conditioned medium obtained from osteoclasts at different differentiation stages, suggesting that osteoclasts and osteoclast precursors suppressed anabolism and promoted the catabolism of chondrocytes in vitro. In contrast, the function of osteoclasts was more significant than osteoclast precursors. Further blocking of osteoclast exosome secretion by using GW4869 abolished the effect of osteoclasts on chondrocytes. Functionally, exosomal transfer of osteoclast-derived miR-212-3p inhibited Smad2 to mediate chondrocyte dysfunction, thus accelerating cartilage matrix degradation in OA via TGF-ß1/Smad2 signaling. The mechanism was also confirmed within the articular cartilage in OA patients and surgery-induced OA mice. Our study provides new information on intercellular interactions in the bone microenvironment within articular cartilage and subchondral bone during OA progression. The miR-212-3p/Smad2 axis is a potential target for the prevention and therapy of OA.


Assuntos
Cartilagem Articular , MicroRNAs , Osteoartrite , Animais , Humanos , Camundongos , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Osteoartrite/metabolismo , Osteoclastos/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
7.
Environ Sci Pollut Res Int ; 30(57): 120300-120314, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37936041

RESUMO

Since the Industrial Revolution, crops have been exposed to various changes in the environment, including elevated atmospheric carbon dioxide (CO2) concentration and cadmium (Cd) pollution in soil. However, information about how combined changes affect crop is limited. Here, we have investigated the changes of japonica and indica rice subspecies seedlings under elevated CO2 level (1200 ppm) and Cd exposure (5 µM Cd) conditions compared with ambient CO2 level (400 ppm) and without Cd exposure in CO2 growth chambers with hydroponic experiment. The results showed that elevated CO2 levels significantly promoted seedling growth and rescued the growth inhibition under Cd stress. However, the elevated CO2 levels led to a significant increase in the shoot Cd accumulation of the two rice subspecies. Especially, the increase of shoot Cd accumulation in indica rice was more than 50% compared with control. Further investigation revealed that the decreases in the photosynthetic pigments and photosynthetic rates caused by Cd were attenuated by the elevated CO2 levels. In addition, elevated CO2 levels increased the non-enzymatic antioxidants and significantly enhanced the ascorbate peroxidase (APX) and glutathione reductase (GR) activities, alleviating the lipid peroxidation and reactive oxygen species (ROS) accumulation induced by Cd. Overall, the research revealed how rice responded to the elevated CO2 levels and Cd exposure, which can help modify agricultural practices to ensure food security and food safety in a future high-CO2 world.


Assuntos
Dióxido de Carbono , Oryza , Cádmio , Estresse Oxidativo , Glutationa/metabolismo , Antioxidantes/metabolismo , Plântula/metabolismo
8.
Comput Biol Med ; 167: 107613, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37918259

RESUMO

Thyroid cancer is the most common type of endocrine system cancer. The pre-cancer and early stages are usually benign or slowly growing, and do not need invasive treatments. This study investigated the challenging classification task of four classes of samples, i.e., normal controls (N), thyroid adenomas (TA), papillary thyroid cancers (PTC) and metastasized papillary thyroid cancers (MPTC). We proposed a multi-view progression diagnosis framework ThyroidBloodTest to integrate the two views of RNAseq platelet transcriptomes (View-T) and blood routine (View-B) features. Platelet transcriptome represented the molecular-level information, while the blood routine features were easy to obtain in the clinical practice. Eleven feature selection algorithms and seven classifiers were evaluated for both views. The experimental data suggested the importance of choosing appropriate data analysis algorithms and feature engineering techniques like principal component analysis (PCA). The best ThyroidBloodTest model achieved Acc = 0.8750 for the four-class classification of the N/TA/PTC/MPTC samples based on the integrated feature space of View-T and View-B. The cellular localization cytosol and three post-translational modification types acetylation/phosphorylation/ubiquitination were observed to be enriched in the proteins encoded by the View-T biomarkers. The numbers of different immune cells also contributed positively to the progression diagnosis of thyroid cancer. The proposed multi-view prediction model demonstrated the necessity of integrating both platelet transcriptomes and blood routine tests for the progression diagnosis of thyroid cancer.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/diagnóstico , Câncer Papilífero da Tireoide/genética , Transcriptoma/genética , Carcinoma Papilar/patologia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética
9.
PLoS One ; 18(10): e0287987, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883446

RESUMO

Testicular torsion is a urological emergency. However, surgical detorsion of the torsed spermatic cord can cause testicular reperfusion injury. Although remote ischemic preconditioning (RIPC) has been convincingly shown to protect organs against ischemia/reperfusion (I/R) injury, little is known regarding the effect of RIPC on testicular torsion/detorsion-induced reperfusion injury. Therefore, we aimed to evaluate the effect of RIPC on testes after testicular I/R injury in a rat model in vivo. Male Sprague-Dawley rats were randomly classified into 4 groups: sham-operated (sham), testicular I/R (TI/R), or remote liver (RIPC liver) and limb (RIPC limb) ischemic preconditioning groups. Testis I/R was induced by 3 h of right spermatic cord torsion (720° clockwise), and reperfusion was allowed for 3 hours. In the RIPC group, four cycles of 5 min of ischemia and 5 min of reperfusion were completed 30 min prior to testicular torsion. The ERK1/2 inhibitor U0126 was administered intravenously at the beginning of reperfusion (1 mg/kg). The testes were taken for the oxidative stress evaluations, histology, apoptosis, immunohistochemical and western blotting analysis. Remote liver and limb ischemic preconditioning attenuated ipsilateral and contralateral testicular damage after testicular I/R injury. For example. RIPC reduced testicular swelling and oxidative stress, lessened structural damage, and inhibited the testicular inflammatory response and apoptosis. Furthermore, RIPC treatment enhanced testicular ERK1/2 phosphorylation postI/R. Inhibition of ERK1/2 activity using U0126 eliminated the protection offered by RIPC. Our data demonstrate for the first time that RIPC protects testes against testicular I/R injury via activation of the ERK1/2 signaling pathway.


Assuntos
Traumatismo por Reperfusão , Torção do Cordão Espermático , Ratos , Masculino , Animais , Humanos , Testículo/metabolismo , Ratos Sprague-Dawley , Torção do Cordão Espermático/complicações , Torção do Cordão Espermático/terapia , Torção do Cordão Espermático/patologia , Isquemia/complicações , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo
10.
J Bioinform Comput Biol ; 21(4): 2350018, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37675491

RESUMO

Over the past decades, many existing drugs and clinical/preclinical compounds have been repositioned as new therapeutic indication from which they were originally intended and to treat off-target diseases by targeting their noncognate protein receptors, such as Sildenafil and Paxlovid, termed drug repurposing (DRP). Despite its significant attraction in the current medicinal community, the DRP is usually considered as a matter of accidents that cannot be fulfilled reliably by traditional drug discovery protocol. In this study, we proposed an integrated computational/experimental (iC/E) strategy to facilitate the DRP within a framework of rational drug design, which was practiced on the identification of new neuronal nitric oxide synthase (nNOS) inhibitors from a structurally diverse, functionally distinct drug pool. We demonstrated that the iC/E strategy is very efficient and readily feasible, which confirmed that the phosphodiesterase inhibitor DB06237 showed a high inhibitory potency against nNOS synthase domain, while other two general drugs, i.e. DB02302 and DB08258, can also inhibit the synthase at nanomolar level. Structural bioinformatics analysis revealed diverse noncovalent interactions such as hydrogen bonds, hydrophobic forces and van der Waals contacts across the complex interface of nNOS active site with these identified drugs, conferring both stability and specificity for the complex recognition and association.


Assuntos
Reposicionamento de Medicamentos , Inibidores Enzimáticos , Óxido Nítrico Sintase Tipo I , Citrato de Sildenafila/farmacologia
11.
FASEB J ; 37(7): e22999, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37249366

RESUMO

Sudden cardiac death (SCD) remains a major cause of global mortality. In addition to modern interventions, botanical folk medicines have long been used to treat cardiovascular disease, although the efficacy and underlying mechanisms are often unresolved. Aloperine, a bioactive quinolizidine alkaloid isolated from Sophora alopecuroides plants, exhibits antioxidant, anti-inflammatory, antitumor, and vasorelaxant properties, but possible antiarrhythmic effects of aloperine in SCD are unclear. Here, we examined whether aloperine protects against ischemia and reperfusion injury-associated lethal ventricular arrhythmia and sudden cardiac death. Rats were divided into sham, control, and aloperine groups, and reperfusion-provoked ventricular arrhythmogenesis, cardiac damage markers, and signaling pathways quantified following left main coronary artery ischemia and reperfusion. In vitro studies of effects of aloperine on hERG and Kv4.3 cardiac voltage-gated potassium (Kv) channels were performed using two-electrode voltage clamp analysis of cloned channels expressed in Xenopus laevis oocytes. Aloperine pretreatment (10 mg/kg) did not affect baseline cardiac electrical stability; yet, it reduced ventricular arrhythmogenesis and susceptibility to SCD (mortality rate: control: 64.3%; aloperine: 0%) induced by reperfusion injury. Aloperine also reduced serum levels of LDH, CK-MB, α-HBDH, and cTnI post-I/R, and stimulated phosphorylation of ventricular ERK1/2 and STAT-3, which are key components of RISK and SAFE signaling pathways. Inhibition of either ERK1/2 (with U0126) or STAT-3 (with Ag490) abolished aloperine-induced anti-arrhythmic effects and ERK1/2 and STAT-3 phosphorylation. Interestingly, while aloperine (100 µM) had no effect on cloned Kv4.3 activity, aloperine (1 µM and up) negative-shifted the voltage dependence of hERG activation by ~10 mV and increased peak hERG current by 35%. Thus, aloperine exerts striking anti-arrhythmic effects against myocardial ischemia and reperfusion injury-induced severe lethal ventricular arrhythmia and sudden cardiac death via the ERK1/2/STAT-3 signaling pathway, with potential additional contribution from increased cardiac myocyte repolarization capacity via augmented hERG activity.


Assuntos
Alcaloides , Traumatismo por Reperfusão Miocárdica , Ratos , Animais , Antiarrítmicos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/metabolismo , Morte Súbita Cardíaca/prevenção & controle , Miócitos Cardíacos/metabolismo , Arritmias Cardíacas/tratamento farmacológico , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/prevenção & controle , Piperidinas/farmacologia , Alcaloides/farmacologia
12.
Am J Physiol Regul Integr Comp Physiol ; 324(6): R747-R760, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37036302

RESUMO

Torsion of the spermatic cord is a urological emergency that must be treated immediately with surgery, yet detorsion of the testis can cause testicular tissue damage because of ischemia-reperfusion (I/R) injury. I/R injury is a complex pathophysiological process that may affect the functions of distant organs. Here, we examined whether testicular torsion/detorsion (TT) causes myocardial dysfunction. We next investigated the potential beneficial effect and underlying mechanisms of remote ischemic postconditioning (RIPost) on cardiac function after testicular torsion/detorsion. Male Sprague-Dawley rats were assigned to three different sets of experimental groups. Testicular I/R was induced by rotating the right testis to 1080° clockwise for 3 h followed by 3 h of detorsion. RIPost was induced at the onset of testicular detorsion by four cycles of 5-min bilateral femoral artery occlusion with 5-min reperfusion. Cardiac function was determined postdetorsion, and the cardioprotective effect of RIPost was examined. Testicular torsion/detorsion-treated rats had reduced serum testosterone levels, impaired systemic hemodynamics, elevated systemic inflammatory responses, and increased serum levels of lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB), α-hydroxybutyrate dehydrogenase (α-HBDH), and cardiac troponin I (cTnI). However, RIPost attenuated remote heart dysfunction induced by testicular torsion/detorsion. Furthermore, RIPost enhanced the phosphorylation of ventricular signal transducer and activator of transcription (STAT)-3, which is a key component of the survivor activating factor enhancement (SAFE) signaling pathways. Inhibition of STAT-3 with Ag490 abolished the RIPost-induced cardioprotection and STAT-3 phosphorylation. Testicular torsion followed by detorsion may cause impaired cardiac function in rats. RIPost effectively attenuates this remote cardiac dysfunction. RIPost-induced protective effects may be mediated by the STAT-3 signaling pathway.


Assuntos
Pós-Condicionamento Isquêmico , Traumatismo por Reperfusão , Torção do Cordão Espermático , Humanos , Ratos , Masculino , Animais , Torção do Cordão Espermático/complicações , Torção do Cordão Espermático/metabolismo , Torção do Cordão Espermático/prevenção & controle , Ratos Sprague-Dawley , Pós-Condicionamento Isquêmico/efeitos adversos , Testículo/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo
13.
Cardiology ; 148(2): 150-160, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36758532

RESUMO

INTRODUCTION: Atrial fibrillation (AF) is the most common cardiac arrhythmia in the general population, and stroke is the most severe complication of AF. Exosomal miRNAs have been reported to be candidates as biomarkers for cardiovascular diseases, including AF and stroke. This study aimed to identify differentially expressed miRNAs (DEMs) in serum exosomes of AF and AF-associated ischemic stroke (AF-IS) patients and evaluate their potential in distinguishing AF and AF-IS patients. METHODS: Serum exosomes were isolated from 8 healthy individuals with sinus rhythm (SR controls), 8 AF patients, and 8 AF-IS patients. miRNA-seq was performed to identify DEMs, and qRT-PCR analysis was performed to confirm the sequencing results. A support vector machine (SVM) model was developed using Python to distinguish AF and AF-IS patients. RESULTS: 68 and 86 DEMs were identified in serum exosomes of AF patients compared to AF-IS patients and SR controls, respectively. Levels of miR-641 and miR-30e-5p were found significantly higher in AF-IS patients. The SVM model achieved an accuracy of 100%, with an area under curve of 1. CONCLUSIONS: The results indicated that miRNA expression profiles of serum exosomes in AF patients were distinct from those in AF-IS patients, and based on the distinction, AF and AF-IS patients can be distinguished.


Assuntos
Fibrilação Atrial , Exossomos , AVC Isquêmico , MicroRNAs , Acidente Vascular Cerebral , Humanos , Fibrilação Atrial/complicações , Fibrilação Atrial/genética , AVC Isquêmico/genética , AVC Isquêmico/metabolismo , Exossomos/genética , Exossomos/metabolismo , Biomarcadores
14.
Sci Rep ; 13(1): 2601, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36788236

RESUMO

This work reports new analytic free in-plane vibration solutions for orthotropic non-Lévy-type rectangular plates, i.e., those without two opposite edges simply supported, by the symplectic superposition method (SSM), which has never been applied to in-plane elasticity problems in any existing works. Such analytic solutions are not accessible through conventional analytic methods as seeking analytic solutions that meet both the governing partial differential equations and various non-Lévy-type boundary conditions is an acknowledged challenge in mechanical analysis of plates. The clamped and free plates are considered as two most representative cases of non-Lévy-type plates. The SSM is implemented in the Hamiltonian system-based symplectic space, where the separation of variables and the symplectic eigen expansion prove to be well-grounded. These two mathematical treatments are adopted to first gain the analytic solutions of two elementary problems. The final analytic free in-plane vibration solutions are obtained by superposition of the two elementary problems. Comprehensive new natural frequencies and vibration modes are studied and validated by reference solutions from the finite element method or other approaches. The rigorous solution procedure, fast convergence, and highly accurate results render the present framework capable of serving as benchmarks for future comparison and applicable to analytic investigation of more plate problems.

15.
Annu Rev Entomol ; 68: 381-399, 2023 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-36689303

RESUMO

Silkworm (Bombyx mori) is not only an economic insect but also a model organism for life science research. Bombyx mori nucleopolyhedrovirus (BmNPV) disease is a major infectious disease in the world's sericulture industry. The cocoon loss caused by this disease accounts for more than 60% of the total loss caused by all silkworm diseases. To date, there has been no effective solution for preventing and treating this disease. The most effective measure is to breed disease-resistant varieties. The quickest way to breed disease-resistant varieties is to apply genetic modification. However, this requires that we obtain disease resistance genes and know the mechanism of disease resistance. Since the discovery of disease-resistant resources in 1989, scholars in the sericulture industry around the world have been inspired to search for resistance genes. In the past two decades, with the help of multi-omics technologies, screening of resistance genes, gene localization, protein modification, virus-host interactions, etc., researchers have found some candidate genes that have been proposed to function at the cellular or individual level. Several disease-resistant varieties have been obtained and used in production through hybrid breeding, RNA interference, and genetic modification. This article summarizes and reviews the discovery of and research advances related to silkworm resistance to BmNPV. It is anticipated that the review will inspire scientific researchers to continue searching for disease resistance genes, clarify the molecular mechanism of silkworm disease resistance, and promote disease-resistant silkworm breeding.


Assuntos
Bombyx , Nucleopoliedrovírus , Animais , Baculoviridae , Bombyx/genética , Bombyx/metabolismo , Resistência à Doença , Nucleopoliedrovírus/genética , Nucleopoliedrovírus/metabolismo
16.
Artigo em Inglês | MEDLINE | ID: mdl-36609949

RESUMO

OBJECTIVE: The SGLT2 inhibitor, canagliflozin, not only reduces glycemia in patients with type 2 diabetes but also exerts cardioprotective effects in individuals without diabetes. However, its potential beneficial effects in cardiac arrest have not been characterized. The purpose of this study was to examine the protective effect of canagliflozin pretreatment on postresuscitation-induced cardiac dysfunction in vivo. METHODS: Male C57/BL6 mice were randomized to vehicle (sham and control) or canagliflozin treatment groups. All mice except for the sham-operated mice were subjected to potassium chloride-induced cardiac arrest followed by chest compressions and intravenous epinephrine for resuscitation. Canagliflozin therapy efficacies were evaluated by electrocardiogram, echocardiography, histological analysis, inflammatory response, serum markers of myocardial injury, protein phosphorylation analysis, and immunohistological assessment. RESULTS: Canagliflozin-pretreated mice exhibited a higher survival rate (P < 0.05), a shorter return of spontaneous circulation (ROSC) time (P < 0.01) and a higher neurological score (P < 0.01 or P < 0.001) than control mice after resuscitation. Canagliflozin was effective at improving cardiac arrest and resuscitation-associated cardiac dysfunction, indicated by increased left ventricular ejection fraction and fractional shortening (P < 0.001). Canagliflozin reduced serum levels of LDH, CK-MB and α-HBDH, ameliorated systemic inflammatory response, and diminished the incidence of early resuscitation-induced arrhythmia. Notably, canagliflozin promoted phosphorylation of cardiac STAT-3 postresuscitation. Furthermore, pharmacological inhibition of STAT-3 by Ag490 blunted STAT-3 phosphorylation and abolished the cardioprotective actions of canagliflozin. CONCLUSIONS: Canagliflozin offered a strong cardioprotective effect against cardiac arrest and resuscitation-induced cardiac dysfunction. This canagliflozin-induced cardioprotection is mediated by the STAT-3-dependent cell-survival signaling pathway.

17.
Sci Rep ; 12(1): 19323, 2022 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-36369319

RESUMO

Renal ischemia/reperfusion (I/R) can induce acute kidney injury. Empagliflozin is a newly developed inhibitor of sodium-glucose cotransporter-2 (SGLT2) approved as an antidiabetic medication for patients with type 2 diabetes mellitus. Despite the established cardioprotective functions of empagliflozin, its protective role in renal I/R is unclear. Here, the present study evaluated the renoprotective effects of empagliflozin in a mouse model of renal I/R injury. Male C57/BL6 mice were allocated to sham-operated, I/R, and empagliflozin groups. Kidney pedicles on both sides were clamped for 45 min and were reperfused for 24 h. Empagliflozin (1 mg/kg) was administered to the mice for 2 days preischemia. The GSK-3ß inhibitor SB216763 was administered intravenously at the beginning of reperfusion (0.1 mg/kg). Renal function and histological scores were evaluated. The kidneys were taken for immunohistochemical analysis, western blotting and apoptosis measurements. We found that empagliflozin decreased serum levels of creatinine and urea, reduced the average kidney weight-to-tibia length ratio, attenuated tubular damage, reduced renal proinflammatory cytokine expression and inhibited apoptosis in injured kidneys. Furthermore, empagliflozin increased renal glycogen synthase kinase 3ß (GSK-3ß) phosphorylation post I/R. Pharmacological inhibition of GSK-3ß activity mimicked the renal protective effects offered by empagliflozin. In summary, these results support a protective role of empagliflozin against renal I/R injury.


Assuntos
Diabetes Mellitus Tipo 2 , Traumatismo por Reperfusão , Camundongos , Masculino , Animais , Glicogênio Sintase Quinase 3 beta , Diabetes Mellitus Tipo 2/patologia , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Rim/metabolismo , Camundongos Endogâmicos C57BL
18.
Biology (Basel) ; 11(8)2022 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-36009761

RESUMO

Calcium ions are important second messengers, playing an important role in the signal transduction pathways. Hyperosmolality gated calcium-permeable channels (OSCA) gene family members play critical modulating roles in response to osmotic-related abiotic stress as well as other abiotic and biotic stresses, which has been reported in many plant species such as Arabidopsis, rice, maize, and wheat. However, there has been no report about the identification and expression profile of the OSCA genes in cucumber. In this study, a total of nine OSCA genes were identified, which are unevenly distributed on the six chromosomes of cucumber. Phylogenetic analysis revealed that the OSCAs of cucumber, Arabidopsis, rice and maize were clustered into four clades. The motif arrangement of CsOSCAs was strongly conserved, and the CsOSCA genes in each group had similar genetic structure. A total of 11 and 10 types of cis-elements related to hormone and stress, respectively, were identified in the promoter regions of CsOSCA genes. Gene expression analysis indicated that the CsOSCA genes have different expression patterns in various tissues, and some of them were regulated by three osmotic-related abiotic stresses (salt, drought and ABA) and three biotic stresses (powdery mildew, downy mildew, and root-knot nematode). As the first genome-wide identification and characterization of the OSCA gene family in cucumber, this study lays a foundation for research on the biological function and evolutionary process of this gene family, which is of great significance for exploiting stress resistant cucumber varieties.

19.
Reproduction ; 164(4): 169-181, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36018772

RESUMO

In brief: Various etiologies can cause uterine myometrium contraction, which leads to preterm birth. This study demonstrates a new functional relationship between the Ras-related C3 botulinum toxin substrate 1 (RAC1) and uterine myometrium contraction in preterm birth. Abstract: Preterm birth (PTB) is a public health issue. The World Health Organization has recommended the use of tocolytic treatment to inhibit preterm labour and improve pregnancy outcomes. Intrauterine inflammation is associated with preterm birth. RAC1 can modulate inflammation in different experimental settings. In the current study, we explored whether RAC1 can modulate spontaneous uterine myometrium contraction in a mouse model of lipopolysaccharide (LPS)-induced intrauterine inflammation. Subsequently, we recorded uterine myometrium contraction and examined uterine Rac1 expression in a mouse model of preterm birth and a case in pregnant women by Western blotting analysis. We also measured progesterone levels in the blood serum of mice. Murine myometrium was obtained 12 h post LPS treatment. Human myometrium was obtained at the time of caesarean section. We found that in the LPS-treated group of mice, uterine myometrium contraction was enhanced, protein levels and activation of RAC1 were increased and serum progesterone levels were decreased. The protein levels of RAC1 were also increased in preterm birth and in pregnant women. NSC23766, a RAC1 inhibitor, attenuated uterine myometrium contraction and diminished RAC1 activation and COX-2 expression. Furthermore, silencing of RAC1 suppressed cell contraction and COX-2 expression in vitro. In conclusion, our results suggested that RAC1 may play an important role in modulating uterine myometrium contraction. Consequently, intervening with RAC1 represents a novel strategy for the treatment of preterm birth.


Assuntos
Miométrio , Neuropeptídeos/metabolismo , Nascimento Prematuro , Proteínas rac1 de Ligação ao GTP/metabolismo , Animais , Cesárea , Ciclo-Oxigenase 2/metabolismo , Feminino , Humanos , Recém-Nascido , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Miométrio/metabolismo , Gravidez , Nascimento Prematuro/etiologia , Nascimento Prematuro/metabolismo , Progesterona/metabolismo , Contração Uterina/fisiologia
20.
J Virol ; 96(14): e0055722, 2022 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-35862702

RESUMO

Baculoviruses have been used as biopesticides for the control of Lepidoptera larvae. However, solar UV radiation reduces the activity of baculovirus. In this study, an UV endonuclease, Bm65, was found encoded in the genome of Bombyx mori nuclear polyhedrosis virus (BmNPV). Bm65 (the ortholog of AcMNPV orf79) was guided by a key nuclear localization signal to enter the nucleus and accumulated at UV-induced DNA damage sites. Subsequent results further showed that Bm65-mediated DNA damage repair was not the only UV damage repair pathway of BmNPV. BmNPV also used host DNA repair proteins to repair UV-induced DNA damage. In summary, these results revealed that Bm65 was very important in UV-induced DNA damage repair of BmNPV, and BmNPV repaired UV-damaged DNA through a variety of ways. IMPORTANCE Baculovirus biopesticides are environmentally friendly insecticides and specifically infect invertebrates. UV radiation from the sunlight greatly reduces the activity of baculovirus biopesticides. However, the molecular mechanisms of most baculoviruses to repair UV-induced DNA damage remain unclear. Nucleotide excision repair (NER) is a major DNA repair pathway that removes UV-induced DNA lesions. At present, there are few reports about the nucleotide excision repair pathway in viruses. Here, we showed for the first time that the baculovirus Bm65 endonuclease actually cleaved UV-damaged DNA. Meanwhile, we found that BmNPV used both viral-encoded enzymes and host DNA damage repair proteins to reverse UV-induced DNA damage. These results will provide a reference for the research of UV damage repair of other viruses.


Assuntos
Dano ao DNA , Reparo do DNA , Endonucleases , Nucleopoliedrovírus , Animais , Agentes de Controle Biológico/metabolismo , Bombyx , Dano ao DNA/efeitos da radiação , Endonucleases/genética , Nucleopoliedrovírus/genética , Nucleopoliedrovírus/metabolismo , Raios Ultravioleta
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