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1.
J Agric Food Chem ; 72(20): 11429-11437, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38738769

RESUMO

Platycodon grandiflorus is a medicinal plant whose main component is platycodins, which have a variety of pharmacological effects and nutritional values. The farnesyl pyrophosphate synthase (FPS) is a key enzyme in the isoprenoid biosynthesis pathway, which catalyzes the synthesis of farnesyl diphosphate (FPP). In this study, we cloned the FPS gene from P. grandiflorus (PgFPS) with an ORF of 1260 bp, encoding 419 amino acids with a deduced molecular weight and theoretical pI of 46,200.98 Da and 6.52, respectively. The squalene content of overexpressed PgFPS in tobacco leaves and yeast cells extract was 1.88-fold and 1.21-fold higher than that of the control group, respectively, and the total saponin content was also increased by 1.15 times in yeast cells extract, which verified the biological function of PgFPS in terpenoid synthesis. After 48 h of MeJA treatment and 6 h of ethephon treatment, the expression of the PgFPS gene in roots and stems reached its peak, showing a 3.125-fold and 3.236-fold increase compared to the untreated group, respectively. Interestingly, the expression of the PgFPS gene in leaves showed a decreasing trend after exogenous elicitors treatment. The discovery of this enzyme will provide a novel perspective for enhancing the efficient synthesis of platycodins.


Assuntos
Clonagem Molecular , Geraniltranstransferase , Proteínas de Plantas , Platycodon , Triterpenos , Platycodon/genética , Platycodon/metabolismo , Platycodon/química , Platycodon/enzimologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/química , Geraniltranstransferase/genética , Geraniltranstransferase/metabolismo , Triterpenos/metabolismo , Triterpenos/química , Regulação da Expressão Gênica de Plantas , Sequência de Aminoácidos
2.
Mol Biol Rep ; 51(1): 618, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38705956

RESUMO

BACKGROUND: Astragalus membranaceus is a plant of the Astragalus genus, which is used as a traditional Chinese herbal medicine with extremely high medicinal and edible value. Astragalus mongholicus, as one of the representative medicinal materials with the same origin of medicine and food, has a rising market demand for its raw materials, but the quality is different in different production areas. Growth-regulating factors (GRF) are transcription factors unique to plants that play important roles in plant growth and development. Up to now, there is no report about GRF in A. mongholicus. METHODS AND RESULTS: This study conducted a genome-wide analysis of the AmGRF gene family, identifying a total of nine AmGRF genes that were classified into subfamily V based on phylogenetic relationships. In the promoter region of the AmGRF gene, we successfully predicted cis-elements that respond to abiotic stress, growth, development, and hormone production in plants. Based on transcriptomic data and real-time quantitative polymerase chain reaction (qPCR) validation, the results showed that AmGRFs were expressed in the roots, stems, and leaves, with overall higher expression in leaves, higher expression of AmGRF1 and AmGRF8 in roots, and high expression levels of AmGRF1 and AmGRF9 in stems. CONCLUSIONS: The results of this study provide a theoretical basis for the further exploration of the functions of AmGRFs in plant growth and development.


Assuntos
Regulação da Expressão Gênica de Plantas , Filogenia , Proteínas de Plantas , Fatores de Transcrição , Regulação da Expressão Gênica de Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Astragalus propinquus/genética , Astragalus propinquus/metabolismo , Família Multigênica , Genoma de Planta , Perfilação da Expressão Gênica/métodos , Regiões Promotoras Genéticas/genética , Astrágalo/genética , Astrágalo/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Estresse Fisiológico/genética , Transcriptoma/genética , Reguladores de Crescimento de Plantas/metabolismo
3.
Bioact Mater ; 38: 305-320, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38745590

RESUMO

Osteochondral regeneration involves the highly challenging and complex reconstruction of cartilage and subchondral bone. Silicon (Si) ions play a crucial role in bone development. Current research on Si ions mainly focuses on bone repair, by using silicate bioceramics with complex ion compositions. However, it is unclear whether the Si ions have important effect on cartilage regeneration. Developing a scaffold that solely releases Si ions to simultaneously promote subchondral bone repair and stimulate cartilage regeneration is critically important. Diatomite (DE) is a natural diatomaceous sediment that can stably release Si ions, known for its abundant availability, low cost, and environmental friendliness. Herein, a hierarchical osteochondral repair scaffold is uniquely designed by incorporating gradient DE into GelMA hydrogel. The adding DE microparticles provides a specific Si source for controlled Si ions release, which not only promotes osteogenic differentiation of rBMSCs (rabbit bone marrow mesenchymal stem cells) but also enhances proliferation and maturation of chondrocytes. Moreover, DE-incorporated hierarchical scaffolds significantly promoted the regeneration of cartilage and subchondral bone. The study suggests the significant role of Si ions in promoting cartilage regeneration and solidifies their foundational role in enhancing bone repair. Furthermore, it offers an economic and eco-friendly strategy for developing high value-added osteochondral regenerative bioscaffolds from low-value ocean natural materials.

4.
Heliyon ; 10(7): e28045, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38590863

RESUMO

HD-Zip (Homeodomain-Leucine Zipper) is a family of transcription factors unique to higher plants and plays a vital role in plant growth and development. Increasing research results show that HD-Zip transcription factors are widely involved in many life processes in plants. However, the HD-Zip transcription factor for cannabis, a valuable crop, has not yet been identified. The sequence characteristics, chromosome localization, system evolution, conservative motif, gene structure, and gene expression of the HD-Zip transcription factor in the cannabis genome were systematically studied. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to verify its function. The results showed that cannabis contained 33 HD-Zip gene members. The number of amino acids is 136-849aa, the isoelectric point is 4.54-9.04, and the molecular weight is 23264.32-93147.87Da. Many cis-acting elements are corresponding to hormone and abiotic stress in the HD-Zip family promoter area of cannabis. Sequencing of the transcriptome at 5 tissue sites of hemp, stems, leaves, bracts, and seeds showed similar levels of expression of 33 members of the HD-Zip gene family at 5 tissue sites. Bioinformatics results show that HD-Zip expression is tissue-specific and may be influenced by hormones and environmental factors. This lays a foundation for further research on the gene function of HD-Zip.

5.
Yi Chuan ; 46(3): 199-208, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38632098

RESUMO

Polarity establishment is one of the key factors affecting early embryonic development. Polarity establishment begins with myosin phosphorylation in the 8-cell embryo, and phosphorylation activates actin leading to its initiation of contractility. Subsequently, actin undergoes reorganization to form an apical domain rich in microvilli on the non-contacting surface of each blastomere, and form the actomyosin ring that marks the maturation of the apical domain in conjunction with polar protein complexes and others. From the process of polarity establishment, it can be seen that the formation of the apical domain is influenced by actin-related proteins and polar protein complexes. Some zygote genome activation (ZGA) and lineage-specific genes also regulate polarity establishment. Polarity establishment underlies the first cell lineage differentiation during early embryonic development. It regulates lineage segregation and morphogenesis by affecting asymmetric cell division, asymmetric localization of lineage differentiation factors, and activity of the Hippo signaling pathway. In this review, we systematically summarize the mechanisms of early embryonic polarity establishment and its impact on lineage differentiation in mammals, and discuss the shortcomings of the currently available studies in terms of regulatory mechanisms and species, thereby providing clues and systematic perspectives for elucidating early embryonic polarity establishment.


Assuntos
Actinas , Actomiosina , Animais , Actomiosina/metabolismo , Citocinese , Diferenciação Celular , Linhagem da Célula , Polaridade Celular/fisiologia , Mamíferos/metabolismo
6.
Natl Sci Rev ; 11(4): nwae035, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38463933

RESUMO

Tissue regeneration is a complicated process that relies on the coordinated effort of the nervous, vascular and immune systems. While the nervous system plays a crucial role in tissue regeneration, current tissue engineering approaches mainly focus on restoring the function of injury-related cells, neglecting the guidance provided by nerves. This has led to unsatisfactory therapeutic outcomes. Herein, we propose a new generation of engineered neural constructs from the perspective of neural induction, which offers a versatile platform for promoting multiple tissue regeneration. Specifically, neural constructs consist of inorganic biomaterials and neural stem cells (NSCs), where the inorganic biomaterials endows NSCs with enhanced biological activities including proliferation and neural differentiation. Through animal experiments, we show the effectiveness of neural constructs in repairing central nervous system injuries with function recovery. More importantly, neural constructs also stimulate osteogenesis, angiogenesis and neuromuscular junction formation, thus promoting the regeneration of bone and skeletal muscle, exhibiting its versatile therapeutic performance. These findings suggest that the inorganic-biomaterial/NSC-based neural platform represents a promising avenue for inducing the regeneration and function recovery of varying tissues and organs.

7.
Adv Healthc Mater ; 13(13): e2303217, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38363057

RESUMO

Osteochondral defects are often accompanied by excessive reactive oxygen species (ROS) caused by osteoarthritis or acute surgical inflammation. An inflammatory environment containing excess ROS will not only hinder tissue regeneration but also impact the quality of newly formed tissues. Therefore, there is an urgent need to develop scaffolds with both ROS scavenging and osteochondral repair functions to promote and protect osteochondral tissue regeneration. In this work, by using 3D printing technology, a composite scaffold based on cobalt-incorporated chloroapatite (Co-ClAP) bioceramics, which possesses ROS-scavenging activity and can support cell proliferation, adhesion, and differentiation, is developed. Benefiting from the catalytic activity of Co-ClAP bioceramics, the composite scaffold can protect cells from oxidative damage under ROS-excessive conditions, support their directional differentiation, and simultaneously mediate an anti-inflammatory microenvironment. In addition, it is also confirmed by using rabbit osteochondral defect model that the Co-ClAP/poly(lactic-co-glycolic acid) scaffold can effectively promote the integrated regeneration of cartilage and subchondral bone, exhibiting an ideal repair effect in vivo. This study provides a promising strategy for the treatment of defects with excess ROS and inflammatory microenvironments.


Assuntos
Regeneração Óssea , Cerâmica , Cobalto , Impressão Tridimensional , Alicerces Teciduais , Animais , Coelhos , Alicerces Teciduais/química , Cobalto/química , Cerâmica/química , Cerâmica/farmacologia , Regeneração Óssea/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/química , Antioxidantes/farmacologia , Engenharia Tecidual/métodos , Proliferação de Células/efeitos dos fármacos , Apatitas/química , Diferenciação Celular/efeitos dos fármacos , Condrócitos/citologia , Condrócitos/efeitos dos fármacos , Condrócitos/metabolismo
8.
Mitochondrial DNA B Resour ; 9(1): 219-222, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38298224

RESUMO

Jacobaea cannabifolia is a widely used medicinal plant. The total length of the chloroplast genome was 151,390 bp, and it comprised a large single-copy (LSC, 83,432 bp) region, a small single-copy (SSC, 18,304 bp) region, and a pair of inverted repeats (IRs, 49,654 bp). A total of 130 coding genes were annotated, including 88 protein-coding genes, 8 rRNA genes, and 34 tRNA genes. A phylogenetic tree was showed that J. cannabifolia and other species of the same genus clustered together.

9.
Toxins (Basel) ; 16(2)2024 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-38393146

RESUMO

Ochratoxin A (OTA), a common mycotoxin, can contaminate food and feed and is difficult to remove. Astaxanthin (ASTA), a natural antioxidant, can effectively protect against OTA-induced hepatotoxicity; however, its mechanism of action remains unclear. In the present study, we elucidate the protective effects of ASTA on the OTA-induced damage of the endoplasmic reticulum and mitochondria in broiler liver samples by serum biochemical analysis, antioxidant analysis, qRT-PCR, and Western blot analysis. ASTA inhibited the expressions of ahr, pxr, car, cyp1a1, cyp1a5, cyp2c18, cyp2d6, and cyp3a9 genes, and significantly alleviated OTA-induced liver oxidative damage (SOD, GSH-Px, GSH, MDA). Furthermore, it inhibited OTA-activated endoplasmic reticulum stress genes and proteins (grp94, GRP78, atf4, ATF6, perk, eif2α, ire1, CHOP). ASTA alleviated OTA-induced mitochondrial dynamic imbalance, inhibited mitochondrial division (DRP1, mff), and promoted mitochondrial fusion (OPA1, MFN1, MFN2). In conclusion, ASTA can decrease OTA-induced oxidative damage, thereby alleviating endoplasmic reticulum stress and mitochondrial dynamic imbalance.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Hepatopatias , Ocratoxinas , Animais , Antioxidantes/farmacologia , Dinâmica Mitocondrial , Galinhas , Estresse Oxidativo , Estresse do Retículo Endoplasmático , Apoptose , Xantofilas
10.
Biomater Adv ; 158: 213792, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38281322

RESUMO

Posterior capsule opacification (PCO), as one of the most common late complications after intraocular lens (IOL) implantation in cataract surgery, seriously affects patients' postoperative vision and surgical satisfaction, and can only be treated by laser incision of the posterior capsule. Although drug eluting coating modification have been proved to inhibit PCO effectively, the complicated coating methods and the potential toxicity of the antiproliferative drugs hinders its actual application. In this study, an indocyanine green (ICG) loaded polydopamine (PDA) coating modified IOL (IP-IOL) was designed to prevented PCO. In vitro and in vivo studies have shown that IP-IOL can effectively eliminate lens epithelial cells and significantly reduce the degree of PCO. At the same time, it still has good imaging quality and optical properties. Furthermore, both the near-infrared irradiation and ICG loaded PDA coating modified IOLs have proved to possess high biological safety to eyes. Thus, with easy preparation and safer near-infrared irradiated photothermal/photodynamic synchronous properties, such ICG loaded PDA coating provides an effective yet easier and safer PCO prevention after IOL implantation.


Assuntos
Opacificação da Cápsula , Lentes Intraoculares , Polímeros , Humanos , Opacificação da Cápsula/prevenção & controle , Olho Artificial , Indóis/uso terapêutico , Verde de Indocianina/uso terapêutico
11.
Molecules ; 29(2)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38257334

RESUMO

Trollius chinensis Bunge, a perennial herb belonging to the Ranunculaceae family, has been extensively used in traditional Chinese medicine. Documented in the Supplements to the Compendium of Materia Medica, its medicinal properties encompass a spectrum of applications, including heat clearance, detoxification, alleviation of oral/throat sores, earaches, eye pain, cold-induced fever, and vision improvement. Furthermore, T. chinensis is used in clinical settings to treat upper respiratory infections, pharyngitis, tonsillitis, esoenteritis, canker, bronchitis, etc. It is mainly used to treat inflammation, such as inflammation of the upper respiratory tract and nasal mucosa. This comprehensive review explores the evolving scientific understanding of T. chinensis, covering facets of botany, materia medica, ethnopharmacological use, phytochemistry, pharmacology, and quality control. In particular, the chemical constituents and pharmacological research are reviewed. Polyphenols, mainly flavonoids and phenolic acids, are highly abundant among T. chinensis and are responsible for antiviral, antimicrobial, and antioxidant activities. The flower additionally harbors trace amounts of volatile oil, polysaccharides, and other bioactive compounds. The active ingredients of the flower have fewer side effects, and it is used in children because of its minimal side effects, which has great research potential. These findings validate the traditional uses of T. chinensis and lay the groundwork for further scientific exploration. The sources utilized in this study encompass Web of Science, Pubmed, CNKI site, classic monographs, Chinese Pharmacopoeia, Chinese Medicine Dictionary, and doctoral and master's theses.


Assuntos
Botânica , Materia Medica , Criança , Humanos , Etnofarmacologia , Controle de Qualidade , Inflamação
12.
Shanghai Kou Qiang Yi Xue ; 32(4): 443-448, 2023 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-38044743

RESUMO

The non-surgical treatment of adult concave deformity can be achieved by interdisciplinary solution, which includes condylar relocation, fixed orthodontic, and functional occlusion smile design anterior prosthesis. In this study, an adult patient with concave deformity were treated by maxillary occlusal splint, conventional fixed brackets, and upper anterior teeth porcelain veneers to lead mandibular condyle to centric relation, to correct the dental arches for functional occlusion, and to gain the final desired esthetic achievement after treatments.


Assuntos
Porcelana Dentária , Estética Dentária , Humanos , Adulto , Oclusão Dentária , Côndilo Mandibular
13.
J Tradit Chin Med ; 43(6): 1268-1274, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37946490

RESUMO

Acupuncture has been widely used as an alternative and complementary therapy for premature ovarian insufficiency (POI) in China. However, research to date has not shown that acupuncture is effective for POI compared with hormone replacement therapy (HRT). We will conduct a randomized, controlled, and outcome assessor-blind trial to evaluate the efficacy and safety of acupuncture on POI. Seventy-six patients with POI will be randomly assigned to two groups. The treatment group will receive twenty-eight one-hour sessions of acupuncture treatments, and the control group will receive 12-week HRT. The whole study will consist of a 12-week treatment plan and a 12-week follow-up session. The primary outcome is measured by changes in serum anti-Müllerian hormone and follicle-stimulating hormone (FSH) levels at weeks 12 and 24. Secondary outcome measures include estradiol, luteinizing hormone (LH), LH/FSH ratio, Kupperman index, and menstrual condition. This trial is expected to clarify whether or not acupuncture is effective and safe for POI compared with HRT.


Assuntos
Terapia por Acupuntura , Insuficiência Ovariana Primária , Feminino , Humanos , Insuficiência Ovariana Primária/terapia , Terapia por Acupuntura/métodos , Estradiol , Hormônio Luteinizante , Hormônio Foliculoestimulante , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
J Gastrointest Surg ; 27(11): 2297-2307, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37715013

RESUMO

PURPOSE: To investigate the efficacy of prophylactic hyperthermic intraperitoneal chemotherapy (HIPEC) for advanced gastric cancer (AGC). METHODS: We included 198 patients treated from December 2016 to January 2019; of these patients, the 132 who had clinical T4 gastric cancer were divided into a hyperthermic intraperitoneal chemotherapy group (HIPEC group) and a radical gastrectomy and D2 lymph node dissection group (control group). Because this study was retrospective, we used propensity score matching (PSM) to reduce selectivity bias; we then assessed risk factors for recurrence and compared prognosis in terms of survival in the gastrectomy and prophylactic HIPEC groups. RESULTS: Prophylactic HIPEC reduced the risk of postoperative peritoneal metastasis (PM: 27.5% vs. 10.5%, P = 0.015) and did not increase the risk of postoperative complications, but there was no significant difference in the effect on hepatic metastases or other distant metastases. Risk factors for recurrence included pT4 staging and positive lymph node metastases. Both disease-free survival (DFS: HR 0.592; 95% CI 0.354-0.990; P = 0.042) and peritoneal recurrence-free survival (PFS: HR 0.314; 95% CI 0.127-0.774; P = 0.008) were better in the prophylactic HIPEC group than in the gastrectomy-only group. In addition, there was no difference in the prognosis of patients between the two groups of raltitrexed (RT) and paclitaxel (PTX) for perfusion dosing. CONCLUSION: Our study showed that prophylactic HIPEC could prevent postoperative PM in patients with AGC and did not increase the incidence of postoperative complications. However, it was not found to be effective in the prevention of other metastases, such as hepatic metastases.


Assuntos
Hipertermia Induzida , Neoplasias Hepáticas , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/tratamento farmacológico , Quimioterapia Intraperitoneal Hipertérmica , Estudos Retrospectivos , Prognóstico , Pontuação de Propensão , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Complicações Pós-Operatórias/terapia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/tratamento farmacológico , Terapia Combinada , Procedimentos Cirúrgicos de Citorredução , Taxa de Sobrevida
15.
J Nanobiotechnology ; 21(1): 323, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679734

RESUMO

Posterior capsule opacification (PCO) is the most common complication after cataract surgery. Drug-eluting intraocular lens (IOLs) is a promising concept of PCO treatment in modern cataract surgery. However, the large dose of drugs in IOL leads to uncontrollable and unpredictable drug release, which inevitably brings risks of overtreatment and ocular toxicity. Herein, a low-power NIR-triggered thermosensitive IOL named IDG@P(NIPAM-co-AA)-IOL is proposed to improve security and prevent PCO by synergetic controlled drug therapy and simultaneous photo-therapy. Thermosensitive polymer brushes Poly(N-isopropylacrylamide-co-Acrylic acid) (P(NIPAM-co-AA)) is prepared on IOL via surface-initiated reversible addition-fragmentation chain transfer (SI-RAFT) polymerization. Then, Doxorubicin (DOX) and Indocyanine green (ICG) co-loaded Gelatin NPs (IDG NPs) are loaded in P(NIPAM-co-AA) by temperature control. The IDG NPs perform in suit photodynamic & photothermal therapy (PTT&PDT), and the produced heat also provides a trigger for controllable drug therapy with a cascade effect. Such functional IOL shows excellent synergistic drug-phototherapy effect and NIR-triggered drug release behavior. And there is no obvious PCO occurrence in IDG@P(NIPAM-co-AA) IOL under NIR irradiation compared with control group. This proposed IDG@P(NIPAM-co-AA)-IOL serves as a promising platform that combines phototherapy and drug-therapy to enhance the therapeutic potential and medication safety for future clinical application of PCO treatment.


Assuntos
Opacificação da Cápsula , Lentes Intraoculares , Humanos , Opacificação da Cápsula/prevenção & controle , Fototerapia , Terapia Combinada , Doxorrubicina
16.
Mater Horiz ; 10(9): 3773-3784, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37409407

RESUMO

Hair loss caused by the abnormal functions of hair follicles in skin can seriously impact the quality of an individual's life. The development of sophisticated skin tissue-engineered constructs is required to enable the function recovery of hair follicles. However, effective hair regrowth in skin substitutes still remains a great challenge. In this study, a 3D multicellular micropattern was successfully fabricated by arranging the hair follicle-related cells orderly distributed in the interval of vascular-cell networks via bioprinting technology. By combining the stable biomimetic micropattern structure and the bio-inducing substrate incorporated with magnesium silicate (MS) nanomaterials, the 3D multicellular micropattern possessed significant follicular potential and angiogenic capacity in vitro. Furthermore, the 3D multicellular micropattern with MS incorporation contributed to efficient hair regrowth during skin tissue regeneration in both immunodeficient mice and androgenetic alopecia (AGA) mice models. Thus, this study proposes a novel 3D micropatterned multicellular system assembling a biomimetic micro-structure and modulating the cell-cell interaction for hair regeneration during skin reconstruction.


Assuntos
Materiais Biocompatíveis , Cabelo , Camundongos , Animais , Materiais Biocompatíveis/metabolismo , Folículo Piloso/metabolismo , Pele/metabolismo , Alopecia/metabolismo
17.
Adv Mater ; 35(42): e2302716, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37434296

RESUMO

Neural-vascular networks are densely distributed through periosteum, cortical bone, and cancellous bone, which is of great significance for bone regeneration and remodeling. Although significant progress has been made in bone tissue engineering, ineffective bone regeneration, and delayed osteointegration still remains an issue due to the ignorance of intrabony nerves and blood vessels. Herein, inspired by space-filling polyhedra with open architectures, polyhedron-like scaffolds with spatial topologies are prepared via 3D-printing technology to mimic the meshwork structure of cancellous bone. Benefiting from its spatial topologies, polyhedron-like scaffolds greatly promoted the osteogenic differentiation of bone mesenchymal stem cells (BMSCs) via activating PI3K-Akt signals, and exhibiting satisfactory performance on angiogenesis and neurogenesis. Computational fluid dynamic (CFD) simulation elucidates that polyhedron-like scaffolds have a relatively lower area-weighted average static pressure, which is beneficial to osteogenesis. Furthermore, in vivo experiments further demonstrate that polyhedron-like scaffolds obviously promote bone formation and osteointegration, as well as inducing vascularization and ingrowth of nerves, leading to innervated and vascularized bone regeneration. Taken together, this work offers a promising approach for fabricating multifunctional scaffolds without additional exogenous seeding cells and growth factors, which holds great potential for functional tissue regeneration and further clinical translation.


Assuntos
Materiais Biocompatíveis , Osteogênese , Materiais Biocompatíveis/química , Osteogênese/fisiologia , Alicerces Teciduais/química , Fosfatidilinositol 3-Quinases , Regeneração Óssea , Engenharia Tecidual , Diferenciação Celular , Impressão Tridimensional
18.
Polymers (Basel) ; 15(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37299308

RESUMO

An eco-friendly medium-density fiberboard (MDF) was prepared using vanillin (V) crosslinked chitosan (CS) adhesive through a hot-pressing process. The cross-linking mechanism and the effect of different proportions of added chitosan/vanillin on the mechanical properties and dimensional stability of MDF were investigated. The results showed that vanillin and chitosan are crosslinked to form a three-dimensional network structure due to the Schiff base reaction between the aldehyde group of vanillin and the amino group of chitosan. At the same time, when the mass ratio between vanillin/chitosan was 2:1, MDF obtained the best mechanical properties, the maximum modulus of rupture (MOR) of 20.64 MPa, the mean modulus of elasticity (MOE) of 3005 MPa, the mean internal bonding (IB) of 0.86 MPa, and the mean thickness swelling (TS) of 14.7%. Therefore, the MDF bonded with V-crosslinked CS can be a promising candidate for environmentally-friendly wood-based panels.

19.
IEEE Trans Med Imaging ; 42(11): 3323-3335, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37276115

RESUMO

This paper presents an effective and general data augmentation framework for medical image segmentation. We adopt a computationally efficient and data-efficient gradient-based meta-learning scheme to explicitly align the distribution of training and validation data which is used as a proxy for unseen test data. We improve the current data augmentation strategies with two core designs. First, we learn class-specific training-time data augmentation (TRA) effectively increasing the heterogeneity within the training subsets and tackling the class imbalance common in segmentation. Second, we jointly optimize TRA and test-time data augmentation (TEA), which are closely connected as both aim to align the training and test data distribution but were so far considered separately in previous works. We demonstrate the effectiveness of our method on four medical image segmentation tasks across different scenarios with two state-of-the-art segmentation models, DeepMedic and nnU-Net. Extensive experimentation shows that the proposed data augmentation framework can significantly and consistently improve the segmentation performance when compared to existing solutions. Code is publicly available at https://github.com/ZerojumpLine/JCSAugment.

20.
Food Chem ; 426: 136629, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37331146

RESUMO

In this study, the contamination of 51 mycotoxins in 416 edible oils were determined by UPLC-MS/MS. Totally, twenty-four mycotoxins were detected and nearly half of the samples (46.9%, n = 195) were contaminated simultaneously with six to nine kinds of mycotoxins. The predominant mycotoxins and contamination characteristics varied depending on the type of oils. More specifically, four enniatins, alternariol monomethyl ether (AME) and zearalenone were the most frequent combination. Overall, peanut and sesame oils (10.7-11.7 mycotoxins on average) were found to be the most contaminated matrices whereas camellia and sunflower seed oils (1.8-2.7 species) were the opposite. Dietary exposure risks of mycotoxins were acceptable in most cases, however, the ingestion of aflatoxins (especially aflatoxin B1) through peanut and sesame oil (margin of exposure: 239.4-386.3 < 10000) exceeded the acceptable carcinogenic risk level. Meanwhile, the risks of cumulative ingestion through the food chain should be of great concern, especially sterigmatocystin, ochratoxin A, AME and zearalenone.


Assuntos
Micotoxinas , Zearalenona , Micotoxinas/análise , Zearalenona/análise , Cromatografia Líquida , Espectrometria de Massas em Tandem , Contaminação de Alimentos/análise , Óleos
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