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1.
Plant Divers ; 46(5): 648-660, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39290888

RESUMO

Relict subtropical coniferous forests in China face severe fragmentation, resulting in declining populations, and some are under significant threat from invasive alien species. Despite the crucial importance of understanding forest dynamics, knowledge gaps persist, particularly regarding the impact of invasive plants on vulnerable natives like Keteleeria evelyniana. In this study, we investigated the impact of invasive plants on the regeneration of forests dominated by K. evelyniana, a subtropical relict species in southwestern China. For this purpose, we characterized forest dynamics of 160 forest plots featuring K. evelyniana as the primary dominant species and determined whether the presence of invasive plants was correlated with regeneration of K. evelyniana. We identified four distinct forest types in which K. evelyniana was dominant. We found that radial growth of K. evelyniana trees is faster in younger age-classes today than it was for older trees at the same age. The population structure of K. evelyniana in each forest type exhibited a multimodal age-class distribution. However, three forest types lacked established saplings younger than 10 years old, a situation attributed to the dense coverage of the invasive alien Ageratina adenophora. This invasive species resulted in a reduction of understory species diversity. Additionally, our analysis uncovered a significant negative correlation in phylogenetic relatedness (net relatedness index) between native and invasive alien plant species in eastern Yunnan. This suggests closely related invasive species face heightened competition, hindering successful invasion. Taken together, our findings indicate that successful establishment and habitat restoration of K. evelyniana seedling/saplings require effective measures to control invasive plants.

2.
Cells ; 13(15)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39120288

RESUMO

Vascular smooth muscle cells (VSMCs) play a critical role in maintaining vascular integrity. VSMC dysfunction leads to numerous vascular diseases. Adenosine deaminases acting on RNA 1 (ADAR1), an RNA editing enzyme, has shown both RNA editing and non-editing functions. Global deletion of ADAR1 causes embryonic lethality, but the phenotype of homozygous ADAR1 deletion specifically in SMCs (ADAR1sm-/-) remains to be determined. By crossing ADAR1fl/fl mice with Myh11-CreERT2 mice followed by Tamoxifen induction, we found that ADAR1sm-/- leads to lethality in adult mice 14 days after the induction. Gross examination revealed extensive hemorrhage and detrimental vascular damage in different organs. Histological analyses revealed destruction of artery structural integrity with detachment of elastin laminae from VSMCs in ADAR1sm-/- aortas. Furthermore, ADAR1sm-/- resulted in severe VSMC apoptosis and mitochondrial dysfunction. RNA sequencing analyses of ADAR1sm-/- aorta segments demonstrated profound transcriptional alteration of genes impacting vascular health including a decrease in fibrillin-1 expression. More importantly, ADAR1sm-/- disrupts the elastin and fibrillin-1 interaction, a molecular event essential for artery structure. Our results indicate that ADAR1 plays a critical role in maintaining SMC survival and vascular stability and resilience.


Assuntos
Adenosina Desaminase , Homeostase , Músculo Liso Vascular , Miócitos de Músculo Liso , Animais , Adenosina Desaminase/metabolismo , Adenosina Desaminase/genética , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Camundongos , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Aorta/metabolismo , Aorta/patologia , Apoptose/genética , Fibrilina-1/genética , Fibrilina-1/metabolismo , Elastina/metabolismo , Camundongos Knockout , Camundongos Endogâmicos C57BL , Proteínas de Ligação a RNA/metabolismo , Proteínas de Ligação a RNA/genética
3.
Mitochondrial DNA B Resour ; 9(7): 929-933, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39077058

RESUMO

Polyspora axillaris (Roxb. ex Ker Gawl.) Sweet 1825, is a shrub or tree that is about 9 meters tall in the Theaceae family, mainly distributed in China and Vietnam, and it is widely used as a green tree species in many regions owing to its rapid growth and good adaptability. It is rich in various beneficial extracts for humans, but there are limited studies on it. In this study, we sequenced and annotated the complete plastome of P. axillaris. The chloroplast genome length of P. axillaris is 156,770 bp, with a total of 132 genes, including 37 tRNA genes, 8 rRNA genes and 87 protein-coding genes. The complete chloroplast genome of P. axillaris contains two Inverted Repeats (IRs) of 26,077 bp, a Large Single-Copy (LSC) region of 86,286 bp and a Small Single-Copy (SSC) region of 18,330 bp. The overall G/C content in the chloroplast is 37.3%. Phylogenetic inference shows that P. axillaris formed a sister relationship with P. hainanensis, along with 10 Theaceae species. The research result of P. axillaris will contribute to the genetic preservation of the species and the phylogenetic study of Polyspora.

4.
Nat Commun ; 15(1): 6382, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39085213

RESUMO

Antifungal echinocandins inhibit the biosynthesis of ß-1,3-glucan, a major and essential polysaccharide component of the fungal cell wall. However, the efficacy of echinocandins against the pathogen Aspergillus fumigatus is limited. Here, we use solid-state nuclear magnetic resonance (ssNMR) and other techniques to show that echinocandins induce dynamic changes in the assembly of mobile and rigid polymers within the A. fumigatus cell wall. The reduction of ß-1,3-glucan induced by echinocandins is accompanied by a concurrent increase in levels of chitin, chitosan, and highly polymorphic α-1,3-glucans, whose physical association with chitin maintains cell wall integrity and modulates water permeability. The rearrangement of the macromolecular network is dynamic and controls the permeability and circulation of the drug throughout the cell wall. Thus, our results indicate that echinocandin treatment triggers compensatory rearrangements in the cell wall that may help A. fumigatus to tolerate the drugs' antifungal effects.


Assuntos
Antifúngicos , Aspergillus fumigatus , Parede Celular , Quitina , Equinocandinas , beta-Glucanas , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/metabolismo , Parede Celular/efeitos dos fármacos , Parede Celular/metabolismo , beta-Glucanas/metabolismo , Antifúngicos/farmacologia , Quitina/metabolismo , Equinocandinas/farmacologia , Quitosana/farmacologia , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Glucanos/biossíntese , Glucanos/metabolismo
5.
Plant Mol Biol ; 114(4): 76, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38888655

RESUMO

Cellulose synthase 5 (CESA5) and CESA6 are known to share substantial functional overlap. In the zinc-finger domain (ZN) of CESA5, there are five amino acid (AA) mismatches when compared to CESA6. These mismatches in CESA5 were replaced with their CESA6 counterparts one by one until all were replaced, generating nine engineered CESA5s. Each N-terminal enhanced yellow fluorescent protein-tagged engineered CESA5 was introduced to prc1-1, a cesa6 null mutant, and resulting mutants were subjected to phenotypic analyses. We found that five single AA-replaced CESA5 proteins partially rescue the prc1-1 mutant phenotypes to different extents. Multi-AA replaced CESA5s further rescued the mutant phenotypes in an additive manner, culminating in full recovery by CESA5G43R + S49T+S54P+S80A+Y88F. Investigations in cellulose content, cellulose synthase complex (CSC) motility, and cellulose microfibril organization in the same mutants support the results of the phenotypic analyses. Bimolecular fluorescence complementation assays demonstrated that the level of homodimerization in every engineered CESA5 is substantially higher than CESA5. The mean fluorescence intensity of CSCs carrying each engineered CESA5 fluctuates with the degree to which the prc1-1 mutant phenotypes are rescued by introducing a corresponding engineered CESA5. Taken together, these five AA mismatches in the ZNs of CESA5 and CESA6 cooperatively modulate the functional properties of these CESAs by controlling their homodimerization capacity, which in turn imposes proportional changes on the incorporation of these CESAs into CSCs.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Glucosiltransferases , Glucosiltransferases/metabolismo , Glucosiltransferases/genética , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/química , Dedos de Zinco , Celulose/metabolismo , Fenótipo , Multimerização Proteica , Mutação , Sequência de Aminoácidos
6.
Photodiagnosis Photodyn Ther ; 48: 104237, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38871017

RESUMO

PURPOSE: To report the use of anterior segment optical coherence tomography (AS-OCT) for superficial keratectomy (SK) in anterior corneal opacity. METHODS: The characteristics of 43 eyes (39 patients) with various lesions responsible for anterior corneal opacity were included in this retrospective non-comparative study. AS-OCT was performed on all eyes before surgery. The thickness of corneal opacity and the underlying healthy stroma were measured. SK was performed on each individual. RESULTS: Four types of anterior corneal opacity were evaluated, including corneal degeneration (26/43), Reis-Bücklers corneal dystrophy (8/43), alkali burn (1/43) and corneal tumors (8/43). Based on AS-OCT images, all eyes showed abnormal hyper-reflective signals in the superficial cornea to less than one-third of the normal corneal thickness in the deepest corneal opacity. All 43 eyes underwent an SK procedure. In addition, 1 eye with alkali burns and 7 eyes with corneal tumors were combined with amniotic membrane transplantation. All eyes restored transparency without significant complications. CONCLUSION: AS-OCT is a valuable method for objective preoperative and noninvasive assessments of anterior corneal opacities and is useful for guiding SK.


Assuntos
Opacidade da Córnea , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Estudos Retrospectivos , Ceratectomia/métodos , Adolescente , Idoso de 80 Anos ou mais , Segmento Anterior do Olho/diagnóstico por imagem , Adulto Jovem , Cirurgia Assistida por Computador/métodos , Resultado do Tratamento
7.
Artigo em Inglês | MEDLINE | ID: mdl-38833147

RESUMO

PURPOSE: The objective of the study is to test the efficacy of cyclopentenyl cytosine (CPEC)-coated stents on blocking artery stenosis, promoting reendothelialization, and reducing thrombosis. METHODS: Scanning electron microscopy was employed to observe the morphological characteristics of stents coated with a mixture of CPEC and poly(lactic-co-glycolic acid) (PLGA) copolymer. PLGA has been used in various Food and Drug Administration (FDA)-approved therapeutic devices. In vitro release of CPEC was tested to measure the dynamic drug elution. Comparison between CPEC- and everolimus-coated stents on neointimal formation and thrombosis formation was conducted after being implanted into the human internal mammary artery and grafted to the mouse aorta. RESULTS: Optimization in stent coating resulted in uniform and consistent coating with minimal variation. In vitro drug release tests demonstrated a gradual and progressive discharge of CPEC. CPEC- or everolimus-coated stents caused much less stenosis than bare-metal stents. However, CPEC stent-implanted arteries exhibited enhanced reendothelialization compared to everolimus stents. Mechanistically, CPEC-coated stents reduced the proliferation of vascular smooth muscle cells while simultaneously promoting reendothelialization. More significantly, unlike everolimus-coated stents, CPEC-coated stents showed a significant reduction in thrombosis formation even in the absence of ongoing anticoagulant treatment. CONCLUSIONS: The study establishes CPEC-coated stent as a promising new device for cardiovascular interventions. By enhancing reendothelialization and preventing thrombosis, CPEC offers advantages over conventional approaches, including the elimination of the need for anti-clogging drugs, which pave the way for improved therapeutic outcomes and management of atherosclerosis-related medical procedures.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38910153

RESUMO

PURPOSE: To validate the Graves ophthalmopathy quality of life (GO-QOL) questionnaire in screening DON and to construct an effective model. METHODS: A total of 194 GO patients were recruited and divided into DON and non-DON (mild and moderate-to-severe) groups. Eye examinations were performed, and quality of life was assessed by the GO-QOL questionnaire. The random forest, decision tree model, receiver operator characteristic (ROC) curve, accuracy and Brier score were determined by R software. RESULTS: In GO-QOL, age, best corrected visual acuity (BCVA), exophthalmos, CAS, severity, and Gorman score were found to be factors related to visual function scores. On the appearance scale, gender, duration of GO, BCVA, exophthalmos, CAS and severity of GO were relevant. Both the visual function scores and appearance scores were significantly lower in DON groups than in non-DON groups (33.18 ± 24.54 versus 81.26 ± 17.39, 60.08 ± 24.82 versus 76.14 ± 27.56). The sensitivity, specificity, and AUC of the visual function scores were 91.1%, 81.7% and 0.939, respectively Visual function scores were used to construct a decision tree model. The sensitivity, specificity, and AUC of the model were 92.9%, 88.0% and 0.941, respectively, with an accuracy of 89.7% and a Brier score of 0.024. CONCLUSIONS: Visual function scores were qualified as a screening method for DON, with a cutoff point of 58. A multifactorial screening model based on visual function scores was constructed.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38868940

RESUMO

BACKGROUND: Plasma concentration of PAI-1 (plasminogen activator inhibitor-1) correlates with arterial stiffness. Vascular smooth muscle cells (SMCs) express PAI-1, and the intrinsic stiffness of SMCs is a major determinant of total arterial stiffness. We hypothesized that PAI-1 promotes SMC stiffness by regulating the cytoskeleton and that pharmacological inhibition of PAI-1 decreases SMC and aortic stiffness. METHODS: PAI-039, a specific inhibitor of PAI-1, and small interfering RNA were used to inhibit PAI-1 expression in cultured human SMCs. Effects of PAI-1 inhibition on SMC stiffness, F-actin (filamentous actin) content, and cytoskeleton-modulating enzymes were assessed. WT (wild-type) and PAI-1-deficient murine SMCs were used to determine PAI-039 specificity. RNA sequencing was performed to determine the effects of PAI-039 on SMC gene expression. In vivo effects of PAI-039 were assessed by aortic pulse wave velocity. RESULTS: PAI-039 significantly reduced intrinsic stiffness of human SMCs, which was accompanied by a significant decrease in cytoplasmic F-actin content. PAI-1 gene knockdown also decreased cytoplasmic F-actin. PAI-1 inhibition significantly increased the activity of cofilin, an F-actin depolymerase, in WT murine SMCs, but not in PAI-1-deficient SMCs. RNA-sequencing analysis suggested that PAI-039 upregulates AMPK (AMP-activated protein kinase) signaling in SMCs, which was confirmed by Western blotting. Inhibition of AMPK prevented activation of cofilin by PAI-039. In mice, PAI-039 significantly decreased aortic stiffness and tunica media F-actin content without altering the elastin or collagen content. CONCLUSIONS: PAI-039 decreases intrinsic SMC stiffness and cytoplasmic stress fiber content. These effects are mediated by AMPK-dependent activation of cofilin. PAI-039 also decreases aortic stiffness in vivo. These findings suggest that PAI-1 is an important regulator of the SMC cytoskeleton and that pharmacological inhibition of PAI-1 has the potential to prevent and treat cardiovascular diseases involving arterial stiffening.

10.
bioRxiv ; 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38617336

RESUMO

Formation of biomolecular condensates can be driven by weak multivalent interactions and emergent polymerization. However, the mechanism of polymerization-mediated condensate formation is less studied. We found lateral root cap cell (LRC)-specific SUPPRESSOR OF RPS4-RLD1 (SRFR1) condensates fine-tune primary root development. Polymerization of the SRFR1 N-terminal domain is required for both LRC condensate formation and optimal root growth. Surprisingly, the first intrinsically disordered region (IDR1) of SRFR1 can be functionally substituted by a specific group of intrinsically disordered proteins known as dehydrins. This finding facilitated the identification of functional segments in the IDR1 of SRFR1, a generalizable strategy to decode unknown IDRs. With this functional information we further improved root growth by modifying the SRFR1 condensation module, providing a strategy to improve plant growth and resilience.

11.
Photodiagnosis Photodyn Ther ; 46: 104067, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38548042

RESUMO

BACKGROUND: To the best of our knowledge, no studies have been performed to determine the optimal parameters of photodynamic therapy (PDT) combined with subconjunctival injection of bevacizumab for corneal neovascularization. This study aimed to compare the effect of photodynamic therapy with two different sets of parameters combined with subconjunctival injection of bevacizumab for corneal neovascularization. METHODS: Patients with stable corneal neovascularization (CNV) unresponsive to conventional treatment (topical steroid) were included in this study. Patients were divided into two groups, receiving PDT with two different sets of parameters (group 1 receiving fluence of 50 J/cm2 at 15 min after intravenous injection of verteporfin with, group 2 receiving fluence of 150 J/cm2 at 60 min after intravenous injection of verteporfin with). Subconjunctival injection of bevacizumab was performed immediately after PDT. All patients were followed for 6 months. Best-corrected visual acuity and intraocular pressure were evaluated, and slit-lamp biomicroscopy as well as digital photography were performed. Average diameter and cumulative length of corneal neovascular were measured to evaluate the corneal neovascularization. RESULTS: Seventeen patients (20 eyes) were included in this study. At the last visit, the vision was improved in 12 eyes (60 %), steady in 4 eyes (20 %) and worsen in 4 eyes (20 %). The intraocular pressure (IOP) of all patients remained in normal range. A significant decrease in corneal neovascularization was showed in all the eyes after treatment. At 6 months after the combined treatment, the average diameter and cumulative length of vessels significantly decreased to 0.041 ± 0.023 mm (P < 0.05) and 18.78 ± 17.73 mm (P < 0.05), respectively, compared with the pretreatment data (0.062 ± 0.015 mm, 31.48 ± 18.21 mm). The reduction was more remarkable in group 2 compared to group 1.In group 1, the average diameter was 0.062 ± 0.013mm before and 0.056 ± 0.017mm after, the cumulative length of vessels was 38.66 ± 22.55mm before and 31.21 ± 17.30 after. In group 2, the date were 0.061 ± 0.016mm before and 0.029 ± 0.020mm after, 25.60 ± 8.95 mm before and 8.61 ± 8.26 mm. The reported complications included epithelial defect in four eyes, small white filaments in two eyes and corneal epithelial erosion in two eyes. CONCLUSION: The PDT combined with subconjunctival injection of bevacizumab was effective for the chronic corneal neovascularization. A more promising treatment outcome was observed when PDT was performed at 60 min after intravenous injection of verteporfin with fluence of 150 J/cm2. No serious complications or systemic events were observed throughout the follow-up period.


Assuntos
Inibidores da Angiogênese , Bevacizumab , Neovascularização da Córnea , Fotoquimioterapia , Fármacos Fotossensibilizantes , Verteporfina , Acuidade Visual , Humanos , Fotoquimioterapia/métodos , Bevacizumab/administração & dosagem , Bevacizumab/uso terapêutico , Neovascularização da Córnea/tratamento farmacológico , Feminino , Masculino , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/uso terapêutico , Verteporfina/uso terapêutico , Inibidores da Angiogênese/administração & dosagem , Pessoa de Meia-Idade , Acuidade Visual/efeitos dos fármacos , Adulto , Idoso , Terapia Combinada , Injeções Intraoculares , Pressão Intraocular/efeitos dos fármacos , Porfirinas/administração & dosagem , Túnica Conjuntiva/irrigação sanguínea
12.
Sci Rep ; 14(1): 7464, 2024 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-38553537

RESUMO

Metabolic dysfunction-associated steatotic liver disease (MASLD) remains the most common cause of liver disease in the United States due to the increased incidence of metabolic dysfunction and obesity. Surfactant protein A (SPA) regulates macrophage function, strongly binds to lipids, and is implicated in renal and idiopathic pulmonary fibrosis (IPF). However, the role of SPA in lipid accumulation, inflammation, and hepatic fibrosis that characterize MASLD remains unknown. SPA deficient (SPA-/-) and age-matched wild-type (WT) control mice were fed a Western diet for 8 weeks to induce MASLD. Blood and liver samples were collected and used to analyze pathological features associated with MASLD. SPA expression was significantly upregulated in livers of mice with MASLD. SPA deficiency attenuated lipid accumulation along with downregulation of genes involved in fatty acid uptake and reduction of hepatic inflammation as evidenced by the diminished macrophage activation, decreased monocyte infiltration, and reduced production of inflammatory cytokines. Moreover, SPA-/- inhibited stellate cell activation, collagen deposit, and liver fibrosis. These results highlight the novel role of SPA in promoting fatty acid uptake into hepatocytes, causing excessive lipid accumulation, inflammation, and fibrosis implicated in the pathogenesis of MASLD.


Assuntos
Fígado Gorduroso , Proteína A Associada a Surfactante Pulmonar , Camundongos , Animais , Dieta Ocidental/efeitos adversos , Fígado Gorduroso/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/complicações , Fibrose , Inflamação/complicações , Lipídeos , Ácidos Graxos
13.
Cell Biol Toxicol ; 40(1): 13, 2024 02 13.
Artigo em Inglês | MEDLINE | ID: mdl-38347241

RESUMO

AIMS: Nuclear protein 1 (Nupr1) is a multifunctional stress-induced protein involved in the regulation of tumorigenesis, apoptosis, and autophagy. However, its role in pulmonary hypertension (PH) after METH exposure remains unexplored. In this study, we aimed to investigate whether METH can induce PH and describe the role and mechanism of Nupr1 in the development of PH. METHODS AND RESULTS: Mice were made to induce pulmonary hypertension (PH) upon chronic intermittent treatment with METH. Their right ventricular systolic pressure (RVSP) was measured to assess pulmonary artery pressure. Pulmonary artery morphometry was determined by H&E staining and Masson staining. Nupr1 expression and function were detected in human lungs, mice lungs exposed to METH, and cultured pulmonary arterial smooth muscle cells (PASMCs) with METH treatment. Our results showed that chronic intermittent METH treatment successfully induced PH in mice. Nupr1 expression was increased in the cultured PASMCs, pulmonary arterial media from METH-exposed mice, and METH-ingested human specimens compared with control. Elevated Nupr1 expression promoted PASMC phenotype change from contractile to synthetic, which triggered pulmonary artery remodeling and resulted in PH formation. Mechanistically, Nupr1 mediated the opening of store-operated calcium entry (SOCE) by activating the expression of STIM1, thereby promoting Ca2+ influx and inducing phenotypic conversion of PASMCs. CONCLUSIONS: Nupr1 activation could promote Ca2+ influx through STIM1-mediated SOCE opening, which promoted METH-induced pulmonary artery remodeling and led to PH formation. These results suggested that Nupr1 played an important role in METH-induced PH and might be a potential target for METH-related PH therapy.


Assuntos
Hipertensão Pulmonar , Metanfetamina , Camundongos , Humanos , Animais , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , Metanfetamina/metabolismo , Músculo Liso Vascular/metabolismo , Proteínas Nucleares/metabolismo , Células Cultivadas , Artéria Pulmonar/metabolismo , Miócitos de Músculo Liso/metabolismo , Proliferação de Células
14.
Acta Biomater ; 177: 165-177, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38354873

RESUMO

Four-dimensional (4D) printing unlocks new potentials for personalized biomedical implantation, but still with hurdles of lacking suitable materials. Herein, we demonstrate a bioresorbable shape memory elastomer (SME) with high elasticity at both below and above its phase transition temperature (Ttrans). This SME can be digital light 3D printed by co-polymerizing glycerol dodecanoate acrylate prepolymer (pre-PGDA) with acrylic acid monomer to form crosslinked Poly(glycerol dodecanoate acrylate) (PGDA)-Polyacrylic acid (PAA), or PGDA-PAA network. The printed complex, free-standing 3D structures with high-resolution features exhibit shape programming properties at a physiological temperature. By tuning the pre-PGDA weight ratios between 55 wt% and 70 wt%, Ttrans varies between 39.2 and 47.2 ℃ while Young's moduli (E) range 40-170 MPa below Ttrans with fractural strain (εf) of 170 %-200 %. Above Ttrans, E drops to 1-1.82 MPa which is close to those of soft tissue. Strikingly, εf of 130-180 % is still maintained. In vitro biocompatibility test on the material shows > 90 % cell proliferation and great cell attachment. In vivo vascular grafting trials underline the geometrical and mechanical adaptability of these 4D printed constructs in regenerating the aorta tissue. Biodegradation of the implants shows the possibility of their full replacement by natural tissue over time. To highlight its potential for personalized medicine, a patient-specific left atrial appendage (LAA) occluder was printed and implanted endovascularly into an in vitro heart model. STATEMENT OF SIGNIFICANCE: 4D printed shape-memory elastomer (SME) implants particularly designed and manufactured for a patient are greatly sought-after in minimally invasive surgery (MIS). Traditional shape-memory polymers used in these implants often suffer from issues like unsuitable transition temperatures, poor biocompatibility, limited 3D design complexity, and low toughness, making them unsuitable for MIS. Our new SME, with an adjustable transition temperature and enhanced toughness, is both biocompatible and naturally degradable, particularly in cardiovascular contexts. This allows implants, like biomedical scaffolds, to be programmed at room temperature and then adapt to the body's physiological conditions post-implantation. Our studies, including in vivo vascular grafts and in vitro device implantation, highlight the SME's effectiveness in aortic tissue regeneration and its promising applications in MIS.


Assuntos
Elastômeros , Alicerces Teciduais , Humanos , Elastômeros/química , Alicerces Teciduais/química , Glicerol , Implantes Absorvíveis , Lauratos , Impressão Tridimensional , Acrilatos
15.
J Phys Condens Matter ; 36(18)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38241749

RESUMO

We report on (resonant) x-ray diffraction experiments on the normal state properties of kagome-lattice superconductors KV3Sb5and RbV3Sb5. We have confirmed previous reports indicating that the charge density wave (CDW) phase is characterized by a doubling of the unit cell in all three crystallographic directions. By monitoring the temperature dependence of Bragg peaks associated with the CDW phase, we ascertained that it develops gradually over several degrees, as opposed to CsV3Sb5, where the CDW peak intensity saturates promptly just below the CDW transition temperature. Analysis of symmetry modes indicates that this behavior arises due to lattice distortions linked to the formation of CDWs. These distortions occur abruptly in CsV3Sb5, while they progress more gradually in RbV3Sb5and KV3Sb5. In contrast, the amplitude of the mode leading to the crystallographic symmetry breaking fromP6/mmmtoFmmmappears to develop more gradually in CsV3Sb5as well. Diffraction measurements close to the V K edge and the Sb L1edge show no sensitivity to inversion- or time-symmetry breaking, which are claimed to be associated with the onset of the CDW phase. The azimuthal angle dependence of the resonant diffraction intensity observed at the Sb L1edge is associated with the difference in the population of unoccupied states and the anisotropy of the electron density of certain Sb ions.

16.
Cell Stem Cell ; 31(2): 212-226.e7, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38232727

RESUMO

The effects of exercise on fibro-adipogenic progenitors (FAPs) are unclear, and the direct molecular link is still unknown. In this study, we reveal that exercise reduces the frequency of FAPs and attenuates collagen deposition and adipose formation in injured or disused muscles through Musclin. Mechanistically, Musclin inhibits FAP proliferation and promotes apoptosis in FAPs by upregulating FILIP1L. Chromatin immunoprecipitation (ChIP)-qPCR confirms that FoxO3a is the transcription factor of FILIP1L. In addition, the Musclin/FILIP1L pathway facilitates the phagocytosis of apoptotic FAPs by macrophages through downregulating the expression of CD47. Genetic ablation of FILIP1L in FAPs abolishes the effects of exercise or Musclin on FAPs and the benefits on the reduction of fibrosis and fatty infiltration. Overall, exercise forms a microenvironment of myokines in muscle and prevents the abnormal accumulation of FAPs in a Musclin/FILIP1L-dependent manner. The administration of exogenous Musclin exerts a therapeutic effect, demonstrating a potential therapeutic approach for muscle atrophy or acute muscle injury.


Assuntos
Regulação da Expressão Gênica , Proteínas Musculares , Músculos , Fatores de Transcrição , Humanos , Adipogenia , Diferenciação Celular , Fibrose , Homeostase , Músculo Esquelético/metabolismo , Músculos/metabolismo , Fatores de Transcrição/metabolismo , Animais , Camundongos , Proteínas Musculares/metabolismo
17.
Am J Pathol ; 194(4): 599-611, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37838011

RESUMO

The pathology of atherosclerosis, a leading cause of mortality in patients with cardiovascular disease, involves inflammatory phenotypic changes in vascular endothelial cells. This study explored the role of the dedicator of cytokinesis (DOCK)-2 protein in atherosclerosis. Mice with deficiencies in low-density lipoprotein receptor and Dock2 (Ldlr-/-Dock2-/-) and controls (Ldlr-/-) were fed a high-fat diet (HFD) to induce atherosclerosis. In controls, Dock2 was increased in atherosclerotic lesions, with increased intercellular adhesion molecule (Icam)-1 and vascular cell adhesion molecule (Vcam)-1, after HFD for 4 weeks. Ldlr-/-Dock2-/- mice exhibited significantly decreased oil red O staining in both aortic roots and aortas compared to that in controls after HFD for 12 weeks. In control mice and in humans, Dock2 was highly expressed in the ECs of atherosclerotic lesions. Dock2 deficiency was associated with attenuation of Icam-1, Vcam-1, and monocyte chemoattractant protein (Mcp)-1 in the aortic roots of mice fed HFD. Findings in human vascular ECs in vitro suggested that DOCK2 was required in TNF-α-mediated expression of ICAM-1/VCAM-1/MCP-1. DOCK2 knockdown was associated with attenuated NF-κB phosphorylation with TNF-α, partially accounting for DOCK2-mediated vascular inflammation. With DOCK2 knockdown in human vascular ECs, TNF-α-mediated VCAM-1 promoter activity was inhibited. The findings from this study suggest the novel concept that DOCK2 promotes the pathogenesis of atherosclerosis by modulating inflammation in vascular ECs.


Assuntos
Aterosclerose , Células Endoteliais , Humanos , Animais , Camundongos , Células Endoteliais/metabolismo , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Aterosclerose/patologia , NF-kappa B/metabolismo , Inflamação/patologia , Fatores de Troca do Nucleotídeo Guanina/genética , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo
18.
Angew Chem Int Ed Engl ; 63(6): e202313859, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38055195

RESUMO

Exploitation of key protected wild plant resources makes great sense, but their limited populations become the major barrier. A particular strategy for breaking this barrier was inspired by the exploration of a resource-saving fungal endophyte Penicillium sp. DG23, which inhabits the key protected wild plant Schisandra macrocarpa. Chemical studies on the cultures of this strain afforded eight novel indole diterpenoids, schipenindolenes A-H (1-8), belonging to six diverse skeleton types. Importantly, semisyntheses suggested some key nonenzymatic reactions constructing these molecules and provided targeted compounds, in particular schipenindolene A (Spid A, 1) with low natural abundance. Remarkably, Spid A was the most potent HMG-CoA reductase (HMGCR) degrader among the indole diterpenoid family. It degraded statin-induced accumulation of HMGCR protein, decreased cholesterol levels and acted synergistically with statin to further lower cholesterol. Mechanistically, transcriptomic and proteomic profiling suggested that Spid A potentially activated the endoplasmic reticulum-associated degradation (ERAD) pathway to enhance the degradation of HMGCR, while simultaneously inhibiting the statin-activated expression of many key enzymes in the cholesterol and fatty acid synthesis pathways, thereby strengthening the efficacy of statins and potentially reducing the side effects of statins. Collectively, this study suggests the potential of Spid A for treating cardiovascular disease.


Assuntos
Acil Coenzima A , Inibidores de Hidroximetilglutaril-CoA Redutases , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Degradação Associada com o Retículo Endoplasmático , Proteômica , Colesterol/metabolismo , Indóis
19.
Sci Total Environ ; 912: 168954, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38042188

RESUMO

To investigate the strengthening effects and mechanisms of bioaugmentation on the microbial remediation of uranium-contaminated groundwater via bioreduction coupled to biomineralization, two exogenous microbial consortia with reducing and phosphate-solubilizing functions were screened and added to uranium-contaminated groundwater as the experimental groups (group B, reducing consortium added; group C, phosphate-solubilizing consortium added). ß-glycerophosphate (GP) was selected to stimulate the microbial community as the sole electron donor and phosphorus source. The results showed that bioaugmentation accelerated the consumption of GP and the proliferation of key functional microbes in groups B and C. In group B, Dysgonomonas, Clostridium_sensu_stricto_11 and Clostridium_sensu_stricto_13 were the main reducing bacteria, and Paenibacillus was the main phosphate-solubilizing bacteria. In group C, the microorganisms that solubilized phosphate were mainly unclassified_f_Enterobacteriaceae. Additionally, bioaugmentation promoted the formation of unattached precipitates and alleviated the inhibitory effect of cell surface precipitation on microbial metabolism. As a result, the formation rate of U-phosphate precipitates and the removal rates of aqueous U(VI) in both groups B and C were elevated significantly after bioaugmentation. The U(VI) removal rate was poor in the control group (group A, with only an indigenous consortium). Propionispora, Sporomusa and Clostridium_sensu_stricto_11 may have played an important role in the removal of uranium in group A. Furthermore, the addition of a reducing consortium promoted the reduction of U(VI) to U(IV), and immobilized uranium existed in the form of U(IV)-phosphate and U(VI)-phosphate precipitates in group B. In contrast, U was present mainly as U(VI)-phosphate precipitates in groups A and C. Overall, bioaugmentation with an exogenous consortium resulted in the rapid removal of uranium from groundwater and the formation of U-phosphate minerals and served as an effective strategy for improving the treatment of uranium-contaminated groundwater in situ.


Assuntos
Água Subterrânea , Urânio , Fosfatos/metabolismo , Urânio/metabolismo , Oxirredução , Bactérias/metabolismo , Biodegradação Ambiental
20.
Photodiagnosis Photodyn Ther ; 45: 103935, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38104706

RESUMO

OBJECTIVE: To investigate the changes in macular vessel density (VD) of the superficial layer of retina (SLR) and deep layer of retina (DLR) in dysthyroid optic neuropathy (DON) after high-dose intravenous pulse methylprednisolone (IVMP). MATERIALS AND METHODS: Eighteen DON patients (29 eyes) who completed high-dose IVMP and 16 healthy individuals (32 eyes) were enrolled in this study. Optical coherence tomography angiography (OCTA) image analysis and comprehensive ophthalmic examinations were performed, including the SLR macular whole-image VD (SLR-mwiVD) and DLR-mwiVD, best-corrected visual acuity (BCVA), the mean deviation of visual field (VF-MD), pattern standard deviation of visual field (VF-PSD) and the other parameters. RESULTS: The SLR-mwiVD (41.39 ± 4.71 vs. 48.13 ± 3.68, p < 0.001) and DLR-mwiVD (40.77 ± 5.85 vs. 49.14 ± 7.02, p < 0.001) were decreased in DON compared to control eyes. After IVMP, visual function parameters were improved, and SLR-mwiVD (49.41 ± 3.18, p < 0.001) and DLR-mwiVD (50.41 ± 4.04, p < 0.001) were increased in the DON group compared to pretreatment. The increased SLR-mwiVD and DLR-mwiVD were significantly correlated with improvements in BCVA (Log MAR: from 0.62 ± 0.49 to -0.01 ± 0.03, p < 0.001), VF-MD (from - 6.89 ± 2.89 dB to - 1.75 ± 1.29 dB, p < 0.001) and VF-PSD (from 4.38 ± 2.52 dB to 2.32 ± 1.64 dB, p < 0.001). CONCLUSION: The increase in macular VD was significantly correlated with the improvement in visual function in DON after IVMP. Macular VD changes on OCTA may be a useful indicator for the response in DON after IVMP.


Assuntos
Disco Óptico , Doenças do Nervo Óptico , Fotoquimioterapia , Humanos , Disco Óptico/irrigação sanguínea , Angiofluoresceinografia/métodos , Vasos Retinianos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes , Doenças do Nervo Óptico/tratamento farmacológico
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