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1.
Plant J ; 119(2): 1014-1029, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38805573

RESUMO

Cassava, a pivotal tropical crop, exhibits rapid growth and possesses a substantial biomass. Its stem is rich in cellulose and serves as a crucial carbohydrate storage organ. The height and strength of stems restrict the mechanised operation and propagation of cassava. In this study, the triple helix transcription factor MeGT2.6 was identified through yeast one-hybrid assay using MeCesA1pro as bait, which is critical for cellulose synthesis. Over-expression and loss-of-function lines were generated, and results revealed that MeGT2.6 could promote a significant increase in the plant height, stem diameter, cell size and thickness of SCW of cassava plant. Specifically, MeGT2.6 upregulated the transcription activity of MeGA20ox1 and downregulated the expression level of MeGA2ox1, thereby enhancing the content of active GA3, resulting in a large cell size, high plant height and long stem diameter in cassava. Moreover, MeGT2.6 upregulated the transcription activity of MeCesA1, which promoted the synthesis of cellulose and hemicellulose and produced a thick secondary cell wall. Finally, MeGT2.6 could help supply additional substrates for the synthesis of cellulose and hemicellulose by upregulating the invertase genes (MeNINV1/6). Thus, MeGT2.6 was found to be a multiple regulator; it was involved in GA metabolism and sucrose decomposition and the synthesis of cellulose and hemicellulose.


Assuntos
Celulose , Regulação da Expressão Gênica de Plantas , Giberelinas , Manihot , Proteínas de Plantas , Manihot/genética , Manihot/metabolismo , Celulose/metabolismo , Celulose/biossíntese , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Giberelinas/metabolismo , Parede Celular/metabolismo , Crescimento Celular , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Caules de Planta/genética , Caules de Planta/metabolismo , Caules de Planta/crescimento & desenvolvimento , Polissacarídeos/metabolismo
2.
BMC Oral Health ; 24(1): 549, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730377

RESUMO

BACKGROUND: With the development and utilization of three-dimensional (3D) intraoral scanning (IOS) technology, the morphological characteristics of teeth were quantitatively assessed. In this research, we aimed to explore the prevalence of dental caries in relation to each measurable morphological indicator of the tooth body via 3D intraoral scanning techniques. METHODS: A hospital-based single-centre study was conducted at our hospital from Dec. 2021 to Apr. 2023. A total of 53 patients were involved in the study, providing complete morphological data for 79 teeth. Each patient completed an oral hygiene routine questionnaire and underwent examination by an experienced dentist to evaluate caries conditions before undergoing 3D intraoral scanning to obtain a digital dental model. Geomagic Studio 2014 was used to extract oral morphological data from the models. The acquired data were entered, cleaned and edited using Excel 2016 and subsequently exported to SPSS version 25.0 for analysis. Chi-square analysis and logistic regression analyses were employed to test the associations. RESULTS: Among the participants, 33 (61.1%) were female, with a mean age of 26.52 ± 10.83 years. Significant associations were found between dental caries and the vertical distance between the distal tip and the gum (OR 14.02; 95% CI 1.80-109.07; P = 0.012), the distal lateral horizontal distance of occlusion (OR 0.40; 95% CI 0.18-0.90; P = 0.026), and the mesial horizontal distance of occlusion (OR 2.20; 95% CI 1.12-4.31; P = 0.021). The Hosmer-Lemeshow test indicated a P value of 0.33. CONCLUSIONS: The vertical distance between the distal tip and the gum, the distal lateral horizontal distance of the occlusion and the mesial horizontal distance of the occlusion were the influencing factors for dental caries (identified as independent risk factors). We hypothesize that these factors may be associated with the physiological curvature of teeth and the role of chewing grooves in plaque formation over time. However, further studies involving larger population samples and more detailed age stratification are still needed.


Assuntos
Cárie Dentária , Imageamento Tridimensional , Coroa do Dente , Humanos , Cárie Dentária/diagnóstico por imagem , Cárie Dentária/patologia , Feminino , Masculino , Imageamento Tridimensional/métodos , Adulto , Coroa do Dente/patologia , Coroa do Dente/diagnóstico por imagem , Adolescente
3.
Angew Chem Int Ed Engl ; 63(13): e202317334, 2024 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-38323479

RESUMO

Xeno-nucleic acids (XNAs) are synthetic genetic polymers with improved biological stabilities and offer powerful molecular tools such as aptamers and catalysts. However, XNA application has been hindered by a very limited repertoire of tool enzymes, particularly those that enable de novo XNA synthesis. Here we report that terminal deoxynucleotide transferase (TdT) catalyzes untemplated threose nucleic acid (TNA) synthesis at the 3' terminus of DNA oligonucleotide, resulting in DNA-TNA chimera resistant to exonuclease digestion. Moreover, TdT-catalyzed TNA extension supports one-pot batch preparation of biostable chimeric oligonucleotides, which can be used directly as staple strands during self-assembly of DNA origami nanostructures (DONs). Such TNA-protected DONs show enhanced biological stability in the presence of exonuclease I, DNase I and fetal bovine serum. This work not only expands the available enzyme toolbox for XNA synthesis and manipulation, but also provides a promising approach to fabricate DONs with improved stability under the physiological condition.


Assuntos
Nanoestruturas , Naftalenossulfonatos , Ácidos Nucleicos , Tetroses , Ácidos Nucleicos/química , Oligonucleotídeos/química , DNA Polimerase Dirigida por DNA , DNA Nucleotidilexotransferase , Polímeros , DNA/química
4.
Langmuir ; 38(13): 4014-4027, 2022 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-35312330

RESUMO

Despite the great advancement and wide use of titanium (Ti) and Ti-based alloys in different orthopedic implants, device-related infections remain the major complication in modern orthopedic and trauma surgery. Most of these infections are often caused by both poor antibacterial and osteoinductive properties of the implant surface. Here, we have demonstrated a facile two-step laser nanotexturing and immobilization of silver onto the titanium implants to improve both cellular integration and antibacterial properties of Ti surfaces. The required threshold laser processing power for effective nanotexturing and osseointegration was systematically determined by the level of osteoblast cells mineralized on the laser nanotextured Ti (LN-Ti) surfaces using a neodymium-doped yttrium aluminum garnet laser (Nd:YAG, wavelength of 1.06 µm). Laser processing powers above 24 W resulted in the formation of hierarchical nanoporous structures (average pore 190 nm) on the Ti surface with a 2.5-fold increase in osseointegration as compared to the pristine Ti surface. Immobilization of silver nanoparticles onto the LN-Ti surface was conducted by dip coating in an aqueous silver ionic solution and subsequently converted to silver nanoparticles (AgNPs) by using a low power laser-assisted photocatalytic reduction process. Structural and surface morphology analysis via XRD and SEM revealed a uniform distribution of Ag and the formation of an AgTi-alloy interface on the Ti surface. The antibacterial efficacy of the LN-Ti with laser immobilized silver (LN-Ti/LI-Ag) was tested against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. The LN-Ti/LI-Ag surface was observed to have efficient and stable antimicrobial properties for over 6 days. In addition, it was found that the LN-Ti/LI-Ag maintained a cytocompatibility and bone cell mineralization property similar to the LN-Ti surface. The differential toxicity of the LN-Ti/LI-Ag between bacterial and cellular species qualifies this approach as a promising candidate for novel rapid surface modification of biomedical metal implants.


Assuntos
Nanopartículas Metálicas , Prata , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Lasers , Nanopartículas Metálicas/química , Prata/química , Prata/farmacologia , Propriedades de Superfície , Titânio/química
5.
Nano Lett ; 21(10): 4500-4507, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33989497

RESUMO

Camouflage is often seen in animals, and it presents in both passive and active forms. For instance, the wings of Closterocerus coffeellae exhibit distinct appearances against different backgrounds, while the chameleon actively changes its skin colors to morph into the environment. Herein, we report an artificial skin-like optoelectronic device that enables actively changing appearances and passively morphing into the environment by manipulating light-matter interactions with electrochromic polymers and photonic colloid nanocrystals. To construct the new electrochromic device, highly reflective, yet transmissive photonic nanocrystals are introduced into the gel electrolyte and sandwiched between the layers of electrochromic polymers and ion storage materials. Through voltage-controlled color switching of electrochromic polymers from colored state to bleached state, the degree of light absorbance, transmittance, and reflectance can be finely balanced and precisely modulated with the device. A broad synthesized color gamut and angle-dependent visual effects can be realized on this electronic skin-like device.


Assuntos
Nanopartículas , Polímeros , Cor , Eletrólitos , Fótons
6.
BMC Oral Health ; 22(1): 12, 2022 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-35034610

RESUMO

BACKGROUND: To investigate the difference in the structural composition of salivary flora between chronic periodontitis patients with and without diabetic nephropathy (DN). METHODS: Thirty salivary samples of 15 chronic periodontitis patients with DN (DN group) and 15 chronic periodontitis patients with diabetes but without DN (DM group) were subjected to pyrosequencing of polymerase chain reaction-amplified 16 s ribosomal RNA genes. After diversity testing, the differential flora were analyzed. The sequencing results were compared with GenBank database to determine the type of differential flora using species composition analysis, hierarchical cluster analysis, principal co-ordinate analysis, and species difference analysis. RESULTS: There were significant between-group differences with respect to Gemella, Selenomonas spp, Lactobacillales_unclassified, Bacteria-unclassified and Abiotrophia (p < 0.05). Compared with DM group, the relative abundance of Selenomonas spp. in DN group was significantly higher; the area under the receiver operating characteristic curve of Selenomonas spp. was 0.713 (P < 0.05). Multi-level biological identification and feature maps indicated that Selenomonas spp. might be used as a potential biomarker for DN patients. On binary logistic regression analysis, increase of Selenomonas spp. was related with DN. CONCLUSIONS: We found significant between-group differences in the structural composition of oral flora. The increase in the relative abundance of Selenomonas spp. may be associated with DN in patients with chronic periodontitis.


Assuntos
Periodontite Crônica , Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Microbiota , Bactérias/genética , Periodontite Crônica/complicações , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/complicações , Humanos , RNA Ribossômico 16S/genética
7.
Crit Rev Biotechnol ; 41(3): 406-424, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33749463

RESUMO

In recent decades, silk fibroin (SF) from silkworm Bombyx mori has been extensively researched and applied in several fields, including: cosmetics, biomedicine and biomaterials. The dissolution and regeneration of SF fibers is the key and prerequisite step for the application of silk protein-based materials. Various solvents and dissolving systems have been reported to dissolve SF fibers. However, the dissolution process directly affects the characteristics of SF and particularly impacts the mechanical properties of the resulting silk biomaterials in subsequent processing. The purpose of this review is to summarize the common solvents, the dissolution methods for silk protein, the properties of the resulting SF protein. The suitable use of SF dissolved in the corresponding solvent was also briefly introduced. Recent applications of SF in various biomaterials are also discussed.


Assuntos
Bombyx , Fibroínas , Animais , Materiais Biocompatíveis , Ciência dos Materiais , Seda , Solubilidade
8.
Oral Dis ; 27(7): 1738-1746, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33128313

RESUMO

OBJECTIVES: Dental tissue-derived mesenchymal stem cell (MSC)-mediated tooth regeneration may be a useful therapeutic tool for repairing tooth loss. However, the low success rate of tooth regeneration restricts its clinical application. Identifying key factors for enhancing dentinogenesis in MSCs is crucial for promoting tooth regeneration. MATERIALS AND METHODS: Human dental pulp stem cells (DPSCs) were transfected with retrovirus to obtain SFRP2-over-expressing DPSCs. Alkaline phosphatase (ALP) activity assay, Alizarin red staining, quantitative analysis of calcium, and dentinogenesis-related genes were detected. Additionally, transplantation in a rabbit tooth extraction model was used to explore the role of SFRP2 in dentin regeneration. RESULTS: We found SFRP2 over-expression greatly enhanced ALP activity, and mineralization in DPSCs. Real-time RT-PCR revealed SFRP2 over-expression promoted the expressions of OSX, RUNX2, DSPP, DMP1, and BSP. Moreover, Micro CT analysis showed high-density calcification occurred to a much higher extent in SFRP2 over-expressing group compared to control group in vivo. Additionally, HE staining, immmunohistochemistry staining, and scanning electron microscopy results showed much more dentin-like tissue formed in SFRP2 over-expressing group compared to control group. CONCLUSIONS: Our findings revealed SFRP2 is an important regulator that enhances the dentinogenesis of DPSCs and dentin regeneration in the jaw, which may have clinical applications.


Assuntos
Polpa Dentária , Células-Tronco , Animais , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Dentina , Osteogênese , Coelhos , Regeneração
9.
J Sep Sci ; 43(2): 514-523, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31642160

RESUMO

Ginkgolide B is in great demand worldwide on account of its extensive and excellent pharmacological effects, however, it is difficult to separate and purify ginkgolide B. In this study, ginkgolide B molecularly imprinted polymers were prepared by combining software simulation and molecular imprinting technique, and its characterization and adsorption performed evaluation were performed to understand the adsorption behavior of the polymers. The adsorption equilibrium concentration of molecularly imprinted polymers was 0.70 mg/mL, and the adsorption equilibrium time was 4 h. Meanwhile, the adsorption isotherm of the polymers for ginkgolide B fitted well with the Langmuir model, and the adsorption kinetics was in line with the pseudo-second-order kinetics. In contrast, the adsorption capacity of molecularly imprinted polymers on ginkgolide B was higher than that of non-molecular imprinted polymers, with better selectivity and better adsorption after repeated use for six times. The application experiments showed that molecular imprinted polymers have a good adsorption effect in low purity samples. Therefore, the polymers reported herein can be expected to apply in the adsorption and separation of ginkgolide B samples.


Assuntos
Ginkgolídeos/isolamento & purificação , Lactonas/isolamento & purificação , Simulação de Dinâmica Molecular , Impressão Molecular , Polímeros/isolamento & purificação , Adsorção , Algoritmos , Centrifugação , Ginkgolídeos/química , Cinética , Lactonas/química , Estrutura Molecular , Tamanho da Partícula , Polímeros/química , Software , Propriedades de Superfície
10.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(2): 163-165, 2020 Feb 08.
Artigo em Zh | MEDLINE | ID: mdl-32400992

RESUMO

According to the situation of 34 batches of natural rubber latex condoms tested by our center in 2018, the unqualified items in the product inspection items and the exploratory research results of D4 and D5 content in silicone oil lubricants are analyzed. We make recommendations on product technical requirements or standards to strengthen the quality supervision of products.


Assuntos
Preservativos/normas , Látex , Óleos de Silicone
11.
Mol Phylogenet Evol ; 118: 23-31, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28942015

RESUMO

Coxsackievirus A4 (CV-A4) has been reported frequently in association with many infectious diseases and cases of hand, foot, and mouth disease potentially associated with CV-A4 infection are also identified. This study summarized the Shandong CV-A4 strains isolated from 25years acute flaccid paralysis surveillance, with an emphasis on exploring the phylogenetic analyses and spatiotemporal dynamics of CV-A4 at the global scale. We sampled 43 CV-A4 isolates and utilized VP1 gene to construct phylogenetic trees. Further extensive Bayesian phylogeographic analysis was carried out to investigate the evolution of CV-A4 and understand the spatiotemporal diffusion around the world using BEAST and SPREAD software. Phylogenetic trees showed that CV-A4 emerged to be more active in recent decades and multiple transmission chains were co-circulating. The molecular clock analysis estimated a mean evolutionary rate of 6.4×10-3 substitutions/site/year, and the estimated origin of CV-A4 around 1944. The phylogeographic analyses suggested the origin of CV-A4 could be in the USA, however regional dissemination was mainly located around the Asia-Europe region. The spatiotemporal dynamics of CV-A4 exhibited frequent viral traffic among localities, and virus from Shandong province seemed to have played a central role in spreading around China and neighboring countries. Our phylogenetic description and phylogeographic analyses indicate the importance of large spatial- and temporal-scale studies in understanding epidemiological dynamics of CV-A4, particularly the diffusion routes will be of great importance to global control efforts.


Assuntos
Enterovirus/classificação , Ásia , Teorema de Bayes , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , China , Infecções por Coxsackievirus/diagnóstico , Infecções por Coxsackievirus/transmissão , Infecções por Coxsackievirus/virologia , Enterovirus/genética , Europa (Continente) , Humanos , Tipagem Molecular , Filogenia , Filogeografia , RNA Viral/isolamento & purificação , RNA Viral/metabolismo , Análise Espaço-Temporal
12.
BMC Oral Health ; 18(1): 197, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30497478

RESUMO

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory oral mucosal disease in which comprehensive inflammation-related cytokines are involved. These cytokines are commonly produced by immune cells and specific nonimmune cells including keratinocytes, endothelial cells and fibroblasts. This raises the question of whether fibroblasts in OLP lesions contribute to the inflammatory process upon inflammatory simulation. METHODS: Primary cultured Oral lichen-planus-associated fibroblasts (OLP AFs, n = 5) and normal buccal mucosal fibroblasts (NFs, n = 5) were examined by immunohistochemistry, Western blotting and reverse transcription-polymerase chain reactions (RT-PCR). Various inflammatory mediators were evaluated with a multiplex assay. Differences among groups were assessed using a Student's test or repeated measures one-way ANOVA, as appropriate. RESULTS: OLP AFs express significantly higher levels of α-smooth muscle actin (α-SMA) than NFs, indicating the presence of myofibroblasts. Myofibroblasts secrete Interleukin (IL)-6, IL-8, and tumor necrosis factor-α (TNF-α) in response to Porphyromonas gingivalis lipopolysaccharide (pg. LPS). CONCLUSION: OLP AFs demonstrated α-SMA expression and secreted pro-inflammatory cytokines in response to pg. LPS stimulation.


Assuntos
Citocinas/metabolismo , Fibroblastos/metabolismo , Líquen Plano Bucal/metabolismo , Porphyromonas gingivalis , Adulto , Feminino , Fibroblastos/citologia , Fibroblastos/imunologia , Humanos , Imuno-Histoquímica , Líquen Plano Bucal/microbiologia , Líquen Plano Bucal/patologia , Lipopolissacarídeos/farmacologia , Masculino , Miofibroblastos/metabolismo , Adulto Jovem
13.
Macromol Rapid Commun ; 38(22)2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29027296

RESUMO

Functional polymer-grafting silica nanoparticles hold great promise in diverse applications such as molecule recognition, drug delivery, and heterogeneous catalysis due to high density and uniform distribution of functional groups and their tunable spatial distance. However, conventional grafting methods from monomers mainly consist of one or more extra surface modification steps and a subsequent surface polymerization step. A monomer protonation-dependent surface polymerization strategy is proposed to achieve one-step uniform surface grafting of cross-linked poly(4-vinylpyridine) (P4VP) onto core-shell Fe3 O4 @SiO2 nanostructures. At an approximate pH, partially protonated 4VP sites in aqueous solution can be strongly adsorbed onto deprotonated silanol groups (SiO- ) onto Fe3 O4 @SiO2 nanospheres to ensure prior polymerization of these protonated 4VP sites exclusively onto Fe3 O4 @SiO2 nanoparticles and subsequent polymerization of other 4VP and divinylbenzene monomers harvested by these protonated 4VP monomers onto Fe3 O4 @SiO2 nanoparticles, thereby achieving direct grafting of cross-linked P4VP macromolecules onto Fe3 O4 @SiO2 nanoparticles.


Assuntos
Óxido Ferroso-Férrico/química , Nanopartículas/química , Polivinil/química , Dióxido de Silício/química , Adsorção , Concentração de Íons de Hidrogênio , Nanopartículas/ultraestrutura , Polimerização , Propriedades de Superfície , Termogravimetria , Água/química
14.
J Nanosci Nanotechnol ; 14(9): 7340-4, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25924412

RESUMO

The sub-micron polystyrene (PS) microspheres with adjustable size were firstly synthesized using emulsion polymerization method by adding only a small amount of emulsifier. Then, three dimensionally ordered macroporous alumina with mesoporous walls and adjustable macropore size was facilely prepared by the colloidal template method. The alumina and PS spheres were characterized by nanoparticle size analyzer, SEM, XRD and N2 adsorption. The results show that the polystyrene microsphere has adjustable single-sized pore with diameter in the range of 100-350 nm and the yield is higher than that prepared by soap free emulsion polymerization. The alumina materials as prepared using the PS colloidal crystals as the template, had ordered meso-macroporous structures and adjustable apertures. The mesopores (about 3.6 nm) in γ-alumina were formed by controlling the heat treatment of alumina precursor. BET surface area and pore volume of the hierarchical alumina as obtained can reach to 241.3 m2/g and 0.33 cm3/g, respectively.


Assuntos
Óxido de Alumínio/química , Nanopartículas/química , Poliestirenos/química , Nanotecnologia , Tamanho da Partícula , Porosidade
15.
Toxicol In Vitro ; 100: 105915, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39111404

RESUMO

Microplastic (MP) pollution is a potential threat to marine organisms. In vitro toxicity of MPs and other pollutants, such as pharmaceutically active compounds (PhACs) and brominated flame retardants (BFRs), has been understudied. This study aimed to investigate the effects of polystyrene microplastics (PS-MPs) with different particle sizes on two biomarkers: ethoxyresorufin-O-deethylase (EROD) and glutathione S-transferase (GST) in tilapia liver homogenates. The study also examined the combined effects of PS-MPs with various environmental contaminants, including three metal ions (Cu2+, Zn2+, Pb2+), three BFRs, and six PhACs. PS-MPs alone had no remarkable effects on the two biomarkers at the selected concentrations. However, PS-MPs combined with other pollutants significantly affected the two biomarkers in most situations. For EROD activity, PS + metal ions (except Zn2+ at 1000 µg/L), PS + BFRs (except decabromodiphenyl oxide (BDE-209)) or PS+ trimethoprim (TMP) significantly inhibited activity values, whereas PS+ 4-acetaminophen (AMP) induced EROD activity. For GST, PS together with most tested pollutants (except PS+ ibuprofen (IBF)) greatly decreased the activities. Accordingly, future research should focus on combined toxicity of mixtures to set more reasonable environmental safety evaluation standards.


Assuntos
Citocromo P-450 CYP1A1 , Glutationa Transferase , Fígado , Microplásticos , Poliestirenos , Tilápia , Poluentes Químicos da Água , Animais , Glutationa Transferase/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Tilápia/metabolismo , Microplásticos/toxicidade , Poliestirenos/toxicidade , Poluentes Químicos da Água/toxicidade , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/metabolismo , Retardadores de Chama/toxicidade , Biomarcadores/metabolismo
16.
Anal Methods ; 16(2): 269-275, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38112593

RESUMO

Chlorine-doped MoS2 quantum dots (Cl-MoS2 QDs) embedded in a SiO2 molecularly imprinted polymer (Cl-MoS2 QDs@SiO2@MIP) have been successfully synthesized and can be used for highly selective and sensitive optosensing of quercetin. The novel environmentally friendly sensor integrated the advantages of the Cl-MoS2 QDs and MIP, high sensitivity and specific recognition for quercetin. The as-fabricated sensor is used to detect trace amounts of quercetin, and its fluorescence intensity showed a good linear decline with the increasing concentration of quercetin from 2 ng mL-1 to 200 ng mL-1 with a detection limit of 1.2 ng mL-1 (S/N = 3). The Cl-MoS2 QDs@SiO2@MIP probe was employed to assay the content of quercetin of real onion extract with good performance, which is in fine agreement with the result obtained by high performance liquid chromatography. The developed Cl-MoS2 QDs@SiO2@MIP sensor exhibits promising potential in the detection of quercetin.


Assuntos
Impressão Molecular , Pontos Quânticos , Pontos Quânticos/química , Polímeros Molecularmente Impressos , Cloro , Quercetina , Molibdênio , Dióxido de Silício/química , Impressão Molecular/métodos , Halogênios
17.
Int J Biol Macromol ; 259(Pt 1): 129099, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38176506

RESUMO

Silk fibroin (SF) from the silkworm Bombyx mori is a fibrous protein identified as a widely suitable biomaterial due to its biocompatibility, tunable degradation, and mechanical strength. Various modifications of SF protein can give SF fibers new properties and functions, broadening their applications in textile and biomedical industries. A diverse array of functional modifications on various forms of SF has been reported. In order to provide researchers with a more systematic understanding of the types of functional modifications of SF protein, as well as the corresponding applications, we comprehensively review the different types of functional modifications, including transgenic modification, modifications with chemical groups or biologically active substance, cross-linking and copolymerization without chemical reactions, their specific modification methods and applications. Furthermore, recent applications of SF in various medical biomaterials are briefly discussed.


Assuntos
Bombyx , Fibroínas , Animais , Bombyx/química , Fibroínas/química , Materiais Biocompatíveis/química , Animais Geneticamente Modificados , Têxteis , Seda/química
18.
Am J Clin Nutr ; 120(1): 162-169, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38677523

RESUMO

BACKGROUND: It is unclear whether salivary iodine concentration (SIC) can assess iodine status in females from different water iodine regions. OBJECTIVES: Through a cross-sectional study, we explored the feasibility of SIC as a biomarker to assess iodine status in females and develop optimal cutoff values. METHODS: A total of 1991 females were analyzed in this cross-sectional study from the coastal iodine-deficient areas (CIDAs), inland iodine-deficient areas (IIDAs), iodine-adequate areas (IAAs), iodine-excess areas (IEAs), and iodine extra-high areas (IEHAs). SIC, spot urine iodine concentration (SUIC), and daily total iodine intake (TII) were assessed, and ultrasonography was performed in all subjects. RESULTS: There was a positive correlation between SIC and SUIC (r = 0.67; 95% CI: 0.64, 0.69; P < 0.001), and TII (r = 0.47; 95% CI: 0.43, 0.50; P < 0.001). The prevalence of thyroid nodules (TN) showed an upward trend with SIC increasing (Z = -2.83; P-trend = 0.005). The area under the receiver-operating characteristic (ROC) curve for SIC to assess iodine deficiency was 0.62 (95% CI: 0.60, 0.65; P < 0.001) and 0.75 (95% CI: 0.73, 0.77; P < 0.001) for iodine excess. The cutoff values were as follows: SIC < 93.32 µg/L, iodine deficiency; 93.32-224.60 µg/L, iodine adequacy; and >224.60 µg/L, iodine excess. When SIC > 224.60 µg/L, the odds ratio (OR) for UIC > 300 µg/L, excessive TII, and the prevalence of TN were 6.44, 3.68, and 1.27 (95% CI: 4.98, 8.31; 2.83, 4.79; and 1.02, 1.56, respectively; P < 0.05); when SIC < 93.32 µg/L, the OR for UIC < 100 µg/L and insufficient TII were 2.34 and 1.94 (95% CI: 1.73, 3.14 and 1.33, 2.83, respectively; P < 0.05). CONCLUSIONS: Using SIC as a biomarker, females in CIDA exhibited mild iodine deficiency, those in IIDA and IAA demonstrated moderate iodine deficiency, and those in IEA and IEHA exhibited an excess of iodine, consistent with SUIC to assess iodine status. SIC can be used as a good biomarker to evaluate the iodine status in population.


Assuntos
Biomarcadores , Iodo , Saliva , Nódulo da Glândula Tireoide , Humanos , Iodo/deficiência , Iodo/urina , Iodo/análise , Feminino , Estudos Transversais , Nódulo da Glândula Tireoide/metabolismo , Adulto , Biomarcadores/urina , Saliva/química , Pessoa de Meia-Idade , Estado Nutricional , Adulto Jovem
19.
J Hazard Mater ; 467: 133748, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38350319

RESUMO

Microplastics (MPs) and pesticides commonly exist in the environment, yet the interactions between them and their subsequent impacts on plants remain poorly understood. Thus, this study aimed to investigate the impacts of differently charged polystyrene (PS) MPs, including PS-COO-, PS and PS-NH3+ MPs, on the fate of 14C-labelled new antiviral pesticide Dufulin (DFL) in a hydroponic tomato system. The results showed that MPs greatly reduced the growth of tomato plants, with suppression of 18.4-30.2%. Compared to the control group, PS-COO-, PS and PS-NH3+ MPs also reduced the bioaccumulation of DFL in whole tomato plants by 40.3%, 34.5%, and 26.1%, respectively. Furthermore, MPs influenced the translocation of DFL in plant tissues, and the values decreased at the rates of 38.7%, 26.5% and 15.7% for PS-COO-, PS and PS-NH3+, respectively. Interestingly, compared to the control group, PS-COO- exhibited a profound inhibitory effect on DFL concentrations in tomatoes, potentially resulting in a lower dietary risk in the hydroponic tomato system. This may be due to the strong adsorption between PS-COO- and DFL, and PS-COO- may also inhibit the growth of tomato plants. Overall, our study could provide valuable insights into the risk assessment of DFL in the presence of MPs in plant systems.


Assuntos
Benzotiazóis , Praguicidas , Solanum lycopersicum , Disponibilidade Biológica , Microplásticos/toxicidade , Plásticos , Poliestirenos
20.
Chin Med ; 19(1): 101, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39049005

RESUMO

BACKGROUND: Human health is a complex, dynamic concept encompassing a spectrum of states influenced by genetic, environmental, physiological, and psychological factors. Traditional Chinese Medicine categorizes health into nine body constitutional types, each reflecting unique balances or imbalances in vital energies, influencing physical, mental, and emotional states. Advances in machine learning models offer promising avenues for diagnosing conditions like Alzheimer's, dementia, and respiratory diseases by analyzing speech patterns, enabling complementary non-invasive disease diagnosis. The study aims to use speech audio to identify subhealth populations characterized by unbalanced constitution types. METHODS: Participants, aged 18-45, were selected from the Acoustic Study of Health. Audio recordings were collected using ATR2500X-USB microphones and Praat software. Exclusion criteria included recent illness, dental issues, and specific medical histories. The audio data were preprocessed to Mel-frequency cepstral coefficients (MFCCs) for model training. Three deep learning models-1-Dimensional Convolution Network (Conv1D), 2-Dimensional Convolution Network (Conv2D), and Long Short-Term Memory (LSTM)-were implemented using Python to classify health status. Saliency maps were generated to provide model explainability. RESULTS: The study used 1,378 recordings from balanced (healthy) and 1,413 from unbalanced (subhealth) types. The Conv1D model achieved a training accuracy of 91.91% and validation accuracy of 84.19%. The Conv2D model had 96.19% training accuracy and 84.93% validation accuracy. The LSTM model showed 92.79% training accuracy and 87.13% validation accuracy, with early signs of overfitting. AUC scores were 0.92 and 0.94 (Conv1D), 0.99 (Conv2D), and 0.97 (LSTM). All models demonstrated robust performance, with Conv2D excelling in discrimination accuracy. CONCLUSIONS: The deep learning classification of human speech audio for health status using body constitution types showed promising results with Conv1D, Conv2D, and LSTM models. Analysis of ROC curves, training accuracy, and validation accuracy showed all models robustly distinguished between balanced and unbalanced constitution types. Conv2D excelled with good accuracy, while Conv1D and LSTM also performed well, affirming their reliability. The study integrates constitution theory and deep learning technologies to classify subhealth populations using noninvasive approach, thereby promoting personalized medicine and early intervention strategies.

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