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Highly organized π-aggregate architectures can strongly affect electronic couplings, leading to important photophysical behaviors. With the escalating interest in two-dimensional (2D) materials attributed to their exceptional electronic and optical characteristics, there is growing anticipation that 2D radial-π-stacks built upon radial π-conjugation nanorings, incorporating intra- and inter-ring electronic couplings within the confines of a 2D plane, will exhibit superior topological attributes and distinct properties. Despite their immense potential, the design and synthesis of 2D π-stacks have proven to be a formidable challenge due to the insufficient π-π interactions necessary for stable stacking. In this study, we present the successful preparation of single-layer 2D radial-π-stacks in a solution. Pillar-shaped radially π-conjugated [4]cyclo-naphthodithiophene diimide ([4]C-NDTIs) molecules were tetragonally arranged via in-plane intermolecular π-π interactions. These 2D π-stacks have a unique topology that differs from that of conventional 1D π-stacks and exhibit notable properties, such as acting as a 2D template capable of absorbing C60 guest molecules and facilitating the formation of 2D radial-π-stacks comprising [4]C-NDTI-C60 complexes, rapid exciton delocalization across the 2D plane, and efficient excitation energy funneling towards a trap.
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Brassinosteroids (BRs) function importantly in plant growth and development, but the roles in regulating fruit development and anthocyanin pigmentation remain unclear. Eggplant (Solanum melongena L.) is an important Solanaceae vegetable crop rich in anthocyanins. The fruit size and coloration are important agronomic traits for eggplant breeding. In this study, transgenic eggplant exhibiting endogenous BRs deficiency was created by overexpressing a heterologous BRs-inactivating enzyme gene GhPAG1 driven by CaMV 35 S promoter. 35 S::GhPAG1 eggplant exhibited severe dwarfism, reduced fruit size, and less anthocyanin accumulation. Microscopic observation showed that the cell size of 35 S::GhPAG1 eggplant was significantly reduced compared to WT. Furthermore, the levels of IAA, ME-IAA, and active JAs (JA, JA-ILE, and H2JA) all decreased in 35 S::GhPAG1 eggplant fruit. RNA-Seq analyses showed a decrease in the expression of genes involved in cell elongation, auxin signaling, and JA signaling. Besides, overexpression of GhPAG1 significantly downregulated anthocyanin biosynthetic genes and associated transcription regulators. Altogether, these results strongly suggest that endogenous brassinosteroid deficiency arising from GhPAG1 overexpression impacts eggplant fruit development and anthocyanin coloration mainly by altering hormone homeostasis.
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Antocianinas , Solanum melongena , Antocianinas/metabolismo , Solanum melongena/genética , Solanum melongena/metabolismo , Frutas/metabolismo , Melhoramento Vegetal , Hormônios/metabolismo , Homeostase , Regulação da Expressão Gênica de PlantasRESUMO
Purpose: Blood vessels distribute cells, oxygen, and nutrients throughout the body to support tissue growth and balance. Pericytes and endothelial cells form the inner wall of blood vessels, crucial for organ development and tissue homeostasis by producing paracrine signaling molecules. In the skeletal system, pericyte-derived vascular factors along with angiogenic factors released by bone cells regulate angiogenesis and bone formation. Although the involvement of angiogenic factors and skeletal blood vessels in bone homeostasis is relatively clear, the role of pericytes and the underlying mechanisms remain unknown. Here, our objective was to elucidate the significance of pericytes in regulating osteoclast differentiation. Methods: We used tissue staining to detect the coverage of pericytes and osteoclasts in femoral tissues of osteoporotic mice and mice of different ages, analyzing their correlation. We developed mice with conditionally deleted pericytes, observing changes in bone mass and osteoclast activity using micro-computer tomography and tissue staining to detect the regulatory effect of pericytes on osteoclasts. Pericytes-derived exosomes (PC-EVs) were collected and co-cultured with monocytes that induce osteoclast differentiation to detect the effect of the former on the exosomes. Finally, the specific mechanism of PC-EVs regulating osteoclast differentiation was verified using RNA sequencing and Western blotting. Results: Our study indicates a significant correlation between pericytes and age-related bone resorption. Conditional deletion of pericytes activated bone resorption and led to osteopenia in vivo. We discovered that PC-EVs inhibited the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway, which is mediated by tumor necrosis factor receptor-associated factor 3 (Traf3), negatively regulating osteoclast development and bone resorption. Silencing Traf3 in PC-EVs canceled their inhibitory effect on osteoclast differentiation. Conclusion: Our study provides a novel perspective into the regulatory role of pericytes on bone resorption and may provide potential strategies for developing novel anti-bone resorption therapies.
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Reabsorção Óssea , Exossomos , Animais , Camundongos , Pericitos/metabolismo , Pericitos/patologia , Exossomos/metabolismo , Fator 3 Associado a Receptor de TNF/metabolismo , Fator 3 Associado a Receptor de TNF/farmacologia , Células Endoteliais/metabolismo , Diferenciação Celular , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Reabsorção Óssea/patologiaRESUMO
Objective To explore the association between lipid profiles and left ventricular hypertrophy in a Chinese general population. Methods We conducted a retrospective observational study to investigate the relationship between lipid markers [including triglycerides, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein (HDL) cholesterol, non-HDL-cholesterol, apolipoprotein A-I, apolipoprotein B, lipoprotein[a], and composite lipid profiles] and left ventricular hypertrophy. A total of 309,400 participants of two populations (one from Beijing and another from nationwide) who underwent physical examinations at different health management centers between 2009 and 2018 in China were included in the cross-sectional study. 7,475 participants who had multiple physical examinations and initially did not have left ventricular hypertrophy constituted a longitudinal cohort to analyze the association between lipid markers and the new-onset of left ventricular hypertrophy. Left ventricular hypertrophy was measured by echocardiography and defined as an end-diastolic thickness of the interventricular septum or left ventricle posterior wall > 11 mm. The Logistic regression model was used in the cross-sectional study. Coxmodel and Coxmodel with restricted cubic splines were used in the longitudinal cohort. Results In the cross-sectional study, for participants in the highest tertile of each lipid marker compared to the respective lowest, triglycerides [odds ratio (OR): 1.250, 95%CI: 1.060 to 1.474], HDL-cholesterol (OR: 0.780, 95%CI: 0.662 to 0.918), and lipoprotein(a) (OR: 1.311, 95%CI: 1.115 to 1.541) had an association with left ventricular hypertrophy. In the longitudinal cohort, for participants in the highest tertile of each lipid marker at the baseline compared to the respective lowest, triglycerides [hazard ratio (HR): 3.277, 95%CI: 1.720 to 6.244], HDL-cholesterol (HR: 0.516, 95%CI: 0.283 to 0.940), non-HDL-cholesterol (HR: 2.309, 95%CI: 1.296 to 4.112), apolipoprotein B (HR: 2.244, 95%CI: 1.251 to 4.032) showed an association with new-onset left ventricular hypertrophy. In the Coxmodel with forward stepwise selection, triglycerides were the only lipid markers entered into the final model. Conclusion Lipids levels, especially triglycerides, are associated with left ventricular hypertrophy. Controlling triglycerides level potentiate to be a strategy in harnessing cardiac remodeling but deserve to be further investigated.
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Colesterol , Hipertrofia Ventricular Esquerda , Biomarcadores , HDL-Colesterol , Estudos Transversais , Humanos , Hipertrofia Ventricular Esquerda/epidemiologia , Estudos Retrospectivos , TriglicerídeosRESUMO
Background: Emerging evidence suggests an association between remnant cholesterol (RC) and vascular damage and hypertension. However, this association has not been explored in a large-scale population in China, and a temporal relationship between RC and hypertension also needs to be investigated. Methods: We conducted a retrospective cross-sectional study in 2,199,366 individuals and a longitudinal study in 24,252 individuals with repeated measurements of lipid profile and blood pressure in at least a 3-year follow-up. The logistic model was used to explore the association between lipid components and hypertension in the cross-sectional analysis. The Cox model was used to analyze the association between high RC (HRC) at baseline and the subsequent incidence of hypertension or the association between hypertension at baseline and incidence of HRC. The cross-lagged panel model was applied to analyze the temporal relationship between RC and hypertension. Results: RC level as a continuous variable had the highest correlation with hypertension among lipid profiles, including RC, low-density lipoprotein cholesterol, total cholesterol, non-high-density lipoprotein cholesterol, and triglycerides, with an odds ratio of 1.59 (95% confidence interval: 1.58-1.59). In the longitudinal cohort, HRC at baseline was associated with incident hypertension. We further explored the temporal relationship between RC and hypertension using the cross-lagged analysis, and the results showed that RC increase preceded the development of hypertension, rather than vice versa. Conclusions: RC had an unexpected high correlation with the prevalence and incidence of hypertension. Moreover, RC increase might precede the development of hypertension, suggesting the potential role of RC in the development of hypertension.
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Colesterol/sangue , Hipertensão/etiologia , Lipoproteínas/sangue , Triglicerídeos/sangue , Adulto , Pressão Sanguínea , Estudos Transversais , Feminino , Humanos , Hipertensão/sangue , Hipertensão/epidemiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
BACKGROUND: Infection is a common problem and a major cause of morbidity and mortality for patients in intensive care units (ICUs). According to published meta-analyses, oral care has been found to reduce the risk of nosocomial pneumonia, and has been recommended to improve the oral environment for patients in ICUs. However, relatively little information is available about the effects of oral care in patients without ventilatory support in ICUs. Therefore, this review proposes to evaluate the effectiveness of oral care in preventing pneumonia in non-ventilated ICU patients. METHODS: Eight databases will be searched for relevant literature, including four Chinese and four English online databases, from their inception to the protocol publication date. Records obtained will be managed and screened via Endnote X7. All literature will be selected following pre-established inclusion criteria by two independent review authors to obtain quality trials. The quality of the included records will be evaluated according to the "risk of bias table", recommended by the Cochrane Handbook for Systematic Reviews of Interventions. All the data will be extracted by one author and checked by another. If there is any disagreement, a final agreement will be reached with a third reviewer via consultation. If there are missing data, the original authors will be emailed to ask for it. If enough data were collected, the data synthesis will be performed using Review Manager (RevMan5.3). Both a random effect model and a fixed effect model will be undertaken. A Bayesian meta-analysis will also be performed to estimate the magnitude of the heterogeneity variance and comparing it with the distribution using the WinBUGS software. Otherwise, the results will be reported narratively. The sources of heterogeneity will be determined using meta-regression and subgroup analysis if there is significant heterogeneity. A funnel plot will be used to assess publication bias if there are enough records included. The Cochrane Handbook for Systematic Reviews of Interventions will be followed throughout the system evaluation process. CONCLUSION: This review will provide evidence of oral care for intensive care unit patients without mechanical ventilation to prevent nosocomial pneumonia. TRIAL REGISTRATION: PROSPERO Research registration identifying number: CRD42020146932.
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Unidades de Terapia Intensiva , Respiração Artificial , Teorema de Bayes , Humanos , Metanálise como Assunto , Respiração Artificial/efeitos adversos , Literatura de Revisão como Assunto , Revisões Sistemáticas como AssuntoRESUMO
Thirty-one new 4H-chromene derivatives were designed and synthesized. Their structures were identified with IR, 1H NMR, 13C NMR, and HRMS. The crystal structure of compound 2a was determined by single-crystal X-ray diffraction. Their antifungal activities were evaluated against Pyricularia oryzae, Erysiphe graminis, Coniella diplodiella, Pseudoperonospora cubensis, and Sclerotinia sclerotiorum. These results demonstrated that most compounds exhibited remarkable inhibitory activities at 20 µg/mL. Compounds 4b and 4c displayed excellent antifungal activity against S. sclerotiorum and possessed better efficacy than fluopyram. At the same time, the inhibitory activity of the bioactive compounds was evaluated against succinate dehydrogenase (SDH). The results showed that these compounds possessed outstanding activity. Compounds 4b and 4c displayed better inhibitory activity than fluopyram. The molecular modeling results revealed that compound 4c had stronger affinity to SDH than fluopyram. It is the first time that the inhibitory activity of 4H-chromene analogs against SDH has been reported.
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Benzopiranos , Succinato Desidrogenase , Antifúngicos/farmacologia , Ascomicetos , Benzopiranos/farmacologia , Estrutura Molecular , Relação Estrutura-Atividade , Succinato Desidrogenase/metabolismoRESUMO
The synthesis, structures, and properties of [4]cyclonaphthodithiophene diimides ([4]C-NDTIs) are described. NDTIs as important n-type building blocks were catenated in the α-positions of thiophene rings via an unusual electrochemical-oxidation-promoted macrocyclization route. The thiophene-thiophene junction in [4]C-NDTIs results in an ideal pillar shape. This interesting topology, along with appealing electronic and optical properties inherited from the NDTI units, endows the [4]C-NDTIs with both near-infrared (NIR) light absorptions, strong excitonic coupling, and tight encapsulation of C60 . Stable orientations of the NDTI units in the nanopillars lead to stable inherent chirality, which enables detailed circular dichroism studies on the impact of isomeric structures on π-conjugation. Remarkably, the [4]C-NDTIs maintain the strong π-π stacking abilities of NDTI units and thus adopt two-dimensional (2D) lattice arrays at the molecular level. These nanopillar molecules have great potential to mimic natural photosynthetic systems for the development of multifunctional organic materials.
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Thirty-three new 2, 3-dihydroquinolin-4(1H)-one analogues were designed, synthesized and characterized by IR, 1H NMR, 13C NMR and HRMS. The crystal structures of compounds 2g and 4l were characterized by single crystal X-ray diffraction. Their antifungal activities were determined against five plant pathogenic fungi namely Rhizoctonia solani, Fusarum graminearum, Helminthosporium maydis, Sclerotinia sclerotiorum and Botrytis cinerea. The results indicated that most of them revealed significant antifungal activity at 20â¯mg/L. Compound 4e showed the strongest antifungal activity against Botrytis cinerea and had better effects than the commercial fungicide fluopyram. Meanwhile, the active compounds were evaluated for their inhibitory activities against succinate dehydrogenase (SDH). The results displayed that they exhibited excellent activity. Compound 4e had better inhibitory activity than fluopyram. The molecular modeling results demonstrated that compound 4e could strongly bind to and interact with the binding sites of SDH. The inhibitory activity of 2, 3-dihydroquinolin-4(1H)-one derivatives against SDH has been reported for the first time.
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Antifúngicos/farmacologia , Desenho de Fármacos , Quinolonas/farmacologia , Succinato Desidrogenase/antagonistas & inibidores , Antifúngicos/síntese química , Antifúngicos/química , Ascomicetos/efeitos dos fármacos , Bipolaris/efeitos dos fármacos , Botrytis/efeitos dos fármacos , Botrytis/enzimologia , Relação Dose-Resposta a Droga , Ligantes , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Quinolonas/síntese química , Quinolonas/química , Rhizoctonia/efeitos dos fármacos , Relação Estrutura-Atividade , Succinato Desidrogenase/metabolismo , TermodinâmicaRESUMO
BACKGROUND: In recent years, nanomaterials have been increasingly developed and applied in the field of bone tissue engineering. However, there are few studies on the induction of bone regeneration by tantalum nanoparticles (Ta NPs) and no reports on the effects of Ta NPs on the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) and the underlying mechanisms. The main purpose of this study was to investigate the effects of Ta NPs on bone regeneration and BMSC osteogenic differentiation and the underlying mechanisms. MATERIALS AND METHODS: The effects of Ta NPs on bone regeneration were evaluated in an animal experiment, and the effects of Ta NPs on osteogenic differentiation of BMSCs and the underlying mechanisms were evaluated in cell experiments. In the animal experiment, hematoxylin-eosin (HE) staining and hard-tissue section analysis showed that Ta NPs promoted bone regeneration, and immunohistochemistry revealed elevated expression of BMP2 and Smad4 in cells cultured with Ta NPs. RESULTS: The results of the cell experiments showed that Ta NPs promoted BMSC proliferation, alkaline phosphatase (ALP) activity, BMP2 secretion and extracellular matrix (ECM) mineralization, and the expression of related osteogenic genes and proteins (especially BMP2, Smad4 and Runx2) was upregulated under culture with Ta NPs. Smad4 expression, ALP activity, ECM mineralization, and osteogenesis-related gene and protein expression decreased after inhibiting Smad4. CONCLUSION: These data suggest that Ta NPs have an osteogenic effect and induce bone regeneration by activating the BMP2/Smad4/Runx2 signaling pathway, which in turn causes BMSCs to undergo osteogenic differentiation. This study provides insight into the molecular mechanisms underlying the effects of Ta NPs in bone regeneration.
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Nanoparticles induce neurotoxicity following inhalation, oral administration, intravenous administration, or injection. Different pathways have various corresponding characteristics. Among them, the sensory nerve-to-brain pathways, which are direct neural pathways, bypass barriers such as the blood-brain barrier, which prevents the entry of the majority of nanoparticles into the brain. Subsequently, nanoparticles exert effects on sensory neuroreceptors and sensory nerves, causing central neurotoxicity. However, no studies have summarized sensory nerve-to-brain pathways for transporting nanoparticles. Here, we review recent findings on the potential sensory nerve pathways that promote nanoparticle entry into the brain, the effects of NPs on sensory receptors and sensory nerves, the central neurotoxicity induced by nanoparticles via sensory nerve pathways, and the possible mechanisms underlying these effects. In addition, the limitations of current research and possible trends for future research are also discussed. In summary, we hope that this review will serve as a reference, inspire ideas for further research into the neurotoxicity of nanoparticles, and facilitate the development of protective measures and treatment schemes for nanoparticle-induced neurotoxicity.
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Encéfalo/fisiologia , Nanopartículas/toxicidade , Sistema Nervoso/efeitos dos fármacos , Animais , Barreira Hematoencefálica , Humanos , Síndromes NeurotóxicasRESUMO
The vascular system, which transports oxygen and nutrients, plays an important role in wound healing, cardiovascular disease treatment and bone tissue engineering. Angiogenesis is a complex and delicate regulatory process. Vascular cells, the extracellular matrix (ECM) and angiogenic factors are indispensable in the promotion of lumen formation and vascular maturation to support blood flow. However, the addition of growth factors or proteins involved in proangiogenic effects is not effective for regulating angiogenesis in different microenvironments. The construction of biomaterial scaffolds to achieve optimal growth conditions and earlier vascularization is undoubtedly one of the most important considerations and major challenges among engineering strategies. Nanomaterials have attracted much attention in biomedical applications due to their structure and unique photoelectric and catalytic properties. Nanomaterials not only serve as carriers that effectively deliver factors such as angiogenesis-related proteins and mRNA but also simulate the nano-topological structure of the primary ECM of blood vessels and stimulate the gene expression of angiogenic effects facilitating angiogenesis. Therefore, the introduction of nanomaterials to promote angiogenesis is a great helpful to the success of tissue regeneration and some ischaemic diseases. This review focuses on the angiogenic effects of nanoscaffolds in different types of tissue regeneration and discusses the influencing factors as well as possible related mechanisms of nanomaterials in endothelial neovascularization. It contributes novel insights into the design and development of novel nanomaterials for vascularization and therapeutic applications.
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Nanoestruturas/química , Neovascularização Fisiológica , Animais , Autofagia , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Regeneração , Transdução de SinaisRESUMO
OBJECTIVE: The fabrication of bioactive coatings on metallic implants to enhance osseointegration has become a topic of general interest in orthopedics and dentistry. Hydroxyapatite (HA) coating has been shown to induce bone formation and promote bone-implant integration. Unfortunately, poor mechanical performance has hindered this from becoming a favorable coating material. The majority of present studies have focused in incorporating different elements into HA coatings to improve mechanical properties. In recent years, tantalum (Ta) has received increasing attention due to its excellent biocompatibility and corrosion resistance. The aim of on the present study was to investigate the fabrication and biological performance of Ta-incorporated HA coatings. METHODS: Ta-incorporated HA coatings were fabricated using the plasma spray technique on a titanium substrate, and the surface characteristics and mechanical properties were examined. In addition, the effects of Ta-incorporated HA coatings on the biological behavior of mesenchymal stem cells (BMSCs) were investigated. RESULTS: Ta-incorporated HA coatings with microporous structure had higher roughness and wettability. In addition, the bonding strength of Ta/HA coatings with the substrate was substantially superior to HA coatings. Furthermore, Ta-incorporated HA coatings not only facilitated initial cell adhesion and faster proliferation, but also promoted the osteogenic differentiation of BMSCs. CONCLUSION: These results indicate that the incorporation of Ta could improve mechanical performance and increase the osteogenic activity of HA coatings. The Ta-incorporated HA coating fabricated by plasma spraying is expected to be a promising bio-coating material for metallic implants.
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Materiais Biocompatíveis/química , Durapatita/química , Osteogênese , Tantálio/química , Titânio/química , Animais , Adesão Celular , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Corrosão , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Metais , Osseointegração , Porosidade , Pós , Próteses e Implantes , Desenho de Prótese , Ratos , Ratos Sprague-Dawley , Estresse Mecânico , Propriedades de SuperfícieRESUMO
A case-control study was conducted in Shandong from January to December 2017 to explore the relationship between sleep quality and the risk of active pulmonary tuberculosis (PTB). Seventy-nine patients with type 2 diabetes mellitus coincident with newly diagnosed pulmonary tuberculosis (DM-PTB) and 169 age, sex, and DM course frequency-matched controls (DM alone) were enrolled. Univariate and multivariable unconditional logistic regression analyses were conducted. We further conducted subgroup analyses to explore the relationship between sleep quality and PTB risk, including DM course (≤5 and ï¼5 years), age, sex, and the presence of overweight or obesity (body mass index (BMI) ï¼ 24 kg/m2). Multivariate logistic regression demonstrated that poor sleep quality had a borderline negative association with the odds of PTB (P ï¼ 0.065). Subgroup multivariate analyses showed that poor sleep quality increased the risk of PTB to more than 3 times among patients with a DM course ï¼ 5 years (odds ratio 3.31, 95% confidence interval: 1.08-10.13; P ï¼ 0.036) after adjusting for potential confounding factors including residential area, educational level, BMI, history of contact with tuberculosis patients, smoking, alcohol consumption, physical exercise, immune status, and frequency of blood glucose monitoring. In conclusion, poor sleep quality is an independent risk factor of PTB among DM patients with a course of ï¼ 5 years, which indicates significant epidemiological implications for PTB control.
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Diabetes Mellitus Tipo 2/epidemiologia , Sono , Tuberculose Pulmonar/epidemiologia , Adulto , Idoso , Estudos de Casos e Controles , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de RiscoRESUMO
Silicon-based materials and their oxides are widely used in drug delivery, dietary supplements, implants and dental fillers. Silica nanoparticles (SiNPs) interact with immunocompetent cells and induce immunotoxicity. However, the toxic effects of SiNPs on the immune system have been inadequately reviewed. The toxicity of SiNPs to the immune system depends on their physicochemical properties and the cell type. Assessments of immunotoxicity include determining cell dysfunctions, cytotoxicity and genotoxicity. This review focuses on the immunotoxicity of SiNPs and investigates the underlying mechanisms. The main mechanisms were proinflammatory responses, oxidative stress and autophagy. Considering the toxicity of SiNPs, surface and shape modifications may mitigate the toxic effects of SiNPs, providing a new way to produce these nanomaterials with less toxic impaction.
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Sistema Imunitário/efeitos dos fármacos , Nanopartículas/química , Dióxido de Silício/química , Animais , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Humanos , Sistema Imunitário/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Dióxido de Silício/toxicidade , Receptores Toll-Like/metabolismoRESUMO
Ochratoxin A (OTA) is a mycotoxin identified as a contaminant in grains and wine throughout the world, and convenient, rapid and sensitive detection methods for OTA have been a long-felt need for food safety monitoring. Herein, we presented a new competitive format based lateral flow strip fluorescent aptasensor for one-step determination of OTA in corn samples. Briefly, biotin-cDNA was immobilized on the surface of a nitrocellulose filter on the test line. Without OTA, Cy5-labeled aptamer combined with complementary strands formed a stable double helix. In the presence of OTA, however, the Cy5-aptamer/OTA complexes were generated, and therefore less free aptamer was captured in the test zone, leading to an obvious decrease in fluorescent signals on the test line. The test strip showed an excellent linear relationship in the range from 1 ng·mL-1 to 1000 ng·mL-1 with the LOD of 0.40 ng·mL-1, IC15 value of 3.46 ng·mL-1 and recoveries from 96.4% to 104.67% in spiked corn samples. Thus, the strip sensor developed in this study is an acceptable alternative for rapid detection of the OTA level in grain samples.
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Aptâmeros de Nucleotídeos/química , Carbocianinas/química , Análise de Alimentos/métodos , Ocratoxinas/análise , Zea mays/química , Sensibilidade e EspecificidadeRESUMO
Insulin is widely considered as a classical hormone and drug in maintaining energy and glucose homeostasis. Recently, insulin has been increasingly recognized as an indispensable factor for osteogenesis and bone turnover, but its applications in bone regeneration have been restricted because of the short periods of activity and uncontrolled release. In this study, we incorporated insulin-loaded poly lactic-co-glycolic-acid (PLGA) nanospheres into nano-hydroxyapatite/collagen (nHAC) scaffolds and investigated the bioactivity of the composite scaffolds in vitro and in vivo. Bioactive insulin was successfully released from the nanospheres within the scaffold, and the release kinetics of insulin could be efficiently controlled by uniform-sized nanospheres. The physical characterizations of the composite scaffolds demonstrated that incorporation of nanospheres in nHAC scaffolds using this method did not significantly change the porosity, pore diameters, and compressive strengths of nHAC. In vitro, the insulin-loaded nHAC/PLGA composite scaffolds possessed favorable biological function for bone marrow mesenchymal stem cells adhesion and proliferation, as well as the differentiation into osteoblasts. In vivo, the optimized bone regenerative capability of this composite scaffold was confirmed in rabbit mandible critical size defects. These results demonstrated successful development of a functional insulin-PLGA-nHAC composite scaffold that enhances the bone regeneration capability of nHAC.
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Regeneração Óssea/fisiologia , Colágeno/química , Durapatita/química , Insulina/farmacologia , Nanoestruturas/química , Alicerces Teciduais/química , Adulto , Animais , Regeneração Óssea/efeitos dos fármacos , Diferenciação Celular , Feminino , Humanos , Insulina/administração & dosagem , Ácido Láctico/química , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Pessoa de Meia-Idade , Osteoblastos/citologia , Osteoblastos/fisiologia , Osteogênese , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Porosidade , CoelhosRESUMO
A novel dual-competitive lateral flow aptasensor (LFA) benefited from aptamer and lateral flow strips was first designed by using aflatoxin B1 (AFB1) as the model target. In this LFA assay, the target AFB1 competed with AFB1-hapten at T line for binding to Cy5-labeled AFB1 aptamer and the complementary strand competed with the target AFB1 for binding to Cy5-labeled AFB1 aptamer at C line. The ratio of their fluorescent intensities at the T line and C line (ST/SC ratio) was employed in order to increase the sensitivity for target AFB1 detection. This technique has the limit of detection (LOD) of 0.1ng/mL for AFB1 within the linear range from 0.1ng/mL to 1000ng/mL. Subsequently, the LFA approach was validated using 11 kinds of food and feedstuff samples with a simple aqueous extraction protocol. The test results with different naturally contaminated feedstuffs indicated a good correlation between this LFA and a commercial ELISA kit. The assay can be completed within 20min and its sensitivity, specificity and reproducibility are highly satisfactory. This is the first LFA that has been rigorously validated, which will be greatly beneficial to development of commercial aptamer-based biosensors for food safety, environmental analysis, particularly in clinical diagnosis.
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Aflatoxina B1/análise , Técnicas Biossensoriais , Poluentes Ambientais/análise , Contaminação de Alimentos/análise , Aflatoxina B1/química , Ração Animal/análise , Aptâmeros de Nucleotídeos , Biotina/química , DNA/química , Poluentes Ambientais/química , Soroalbumina Bovina/química , Estreptavidina/químicaRESUMO
PURPOSE: Titanium implant is a widely used method for dental prosthesis restoration. Nevertheless, in patients with systemic diseases, including osteoporosis, diabetes, and cancer, the success rate of the implant is greatly reduced. This study investigates a new implant material loaded with insulin-like growth factor 1 (IGF1), which could potentially improve the implant success rate, accelerate the occurrence of osseointegration, and provide a new strategy for implant treatment in osteoporotic patients. MATERIALS AND METHODS: Biofunctionalized polyelectrolyte multilayers (PEMs) with polyethylenimine as the excitation layer and gelatin/chitosan loaded with IGF1 were prepared on the surface of titanium implant by layer-by-layer self-assembly technique. The physical and chemical properties of the biofunctionalized PEMs, the biological characteristics of bone marrow mesenchymal stem cells (BMMSCs), and bone implant contact correlation test indexes were detected and analyzed in vitro and in vivo using osteoporosis rat model. RESULTS: PEMs coatings loaded with IGF1 (TNS-PEM-IGF1-100) implant promoted the early stage of BMMSCs adhesion. Under the action of body fluids, the active coating showed sustained release of growth factors, which in turn promoted the proliferation and differentiation of BMMSCs and the extracellular matrix. At 8 weeks from implant surgery, the new bone around the implants was examined using micro-CT and acid fuchsin/methylene blue staining. The new bone formation increased with time in each group, while the TNS-PEM-IGF1-100 group showed the highest thickness and continuity. CONCLUSION: TNS-PEM-IGF1-100 new implants can promote osseointegration in osteoporotic conditions both in vivo and in vitro and provide a new strategy for implant repair in osteoporotic patients.
Assuntos
Fator de Crescimento Insulin-Like I/farmacologia , Osseointegração/efeitos dos fármacos , Osteoporose/fisiopatologia , Polieletrólitos/química , Próteses e Implantes , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Interface Osso-Implante , Quitosana/química , Materiais Revestidos Biocompatíveis/química , Materiais Dentários/química , Modelos Animais de Doenças , Feminino , Células-Tronco Mesenquimais/fisiologia , Ratos Sprague-Dawley , Titânio/químicaRESUMO
Insulin is considered to be a classical central regulator of energy homeostasis. Recently, the effect of insulin on bone has gained a lot of attention, but little attention has been paid to the application in bone tissue engineering. In this study, porous nanohydroxyapatite/collagen (nHAC) scaffolds incorporating poly lactic-co-glycolic acid (PLGA) particles were successfully developed as an insulin delivery platform for bone regeneration. Bioactive insulin was successfully released from the PLGA particles within the scaffold, and the size of the particles as well as the release kinetics of the insulin could be efficiently controlled through Shirasu porous glass premix membrane emulsification technology. It was indicated that the nHAC/PLGA composite scaffolds possessed favorable mechanical and structural properties for cell adhesion and proliferation, as well as the differentiation into osteoblasts. It was also demonstrated that the nHAC/PLGA scaffolds implanted into a rabbit critical-size mandible defect possessed tissue compatibility and higher bone restoration capacity compared with the defects that were filled with or without nHAC scaffolds. Furthermore, the in vivo results showed that the nHAC/PLGA scaffolds which incorporated insulin-loaded microspheres with a size of 1.61 µm significantly accelerated bone healing compared with two other composite scaffolds. Our study indicated that the local insulin released at the optimal time could substantially and reproducibly improve bone repair.