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1.
Proc Biol Sci ; 291(2020): 20232340, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38593845

RESUMO

Studies of adaptive radiations have played a central role in our understanding of reproductive isolation. Yet the focus has been on human-biased visual and auditory signals, leaving gaps in our knowledge of other modalities. To date, studies on chemical signals in adaptive radiations have focused on systems with multimodal signalling, making it difficult to isolate the role chemicals play in reproductive isolation. In this study we examine the use of chemical signals in the species recognition and adaptive radiation of Hawaiian Tetragnatha spiders by focusing on entire communities of co-occurring species, and conducting behavioural assays in conjunction with chemical analysis of their silks using gas chromatography-mass spectrometry. Male spiders significantly preferred the silk extracts of conspecific mates over those of sympatric heterospecifics. The compounds found in the silk extracts, long chain alkyl methyl ethers, were remarkably species-specific in the combination and quantity. The differences in the profile were greatest between co-occurring species and between closely related sibling species. Lastly, there were significant differences in the chemical profile between two populations of a particular species. These findings provide key insights into the role chemical signals play in the attainment and maintenance of reproductive barriers between closely related co-occurring species.


Assuntos
Aranhas , Animais , Humanos , Masculino , Havaí , Especificidade da Espécie , Isolamento Reprodutivo , Seda
2.
Sci Prog ; 107(2): 368504241242282, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38614468

RESUMO

This research aims to optimize the silk and wool dyeing process using natural dyes from Bixa orellana (annatto) through response surface methodology. Central composite design experiments highlight the significant enhancement of color outcomes achieved through microwave treatment. For silk, the optimal conditions (80 °C for 40 min) with annatto extract yield a color strength (K/S) of 17.8588, while wool achieves a K/S of 7.5329. Introducing eco-friendly bio-mordants, such as pomegranate peel and red sumac tannins, enhances color strength. Pre-dyeing treatments with 2% red sumac, 1.5% pomegranate peel, and weld flower extracts for silk produce high color strength, with K/S values of 16.4063, 16.3784, and 12.1658, respectively. Post-dyeing, the K/S values increase to 40.1178, 17.4779, and 21.6494. Wool yarn exhibits similar improvements, with pre-dyeing K/S values of 13.1353, 13.5060, and 16.3232, escalating to 10.5892, 15.3141, and 23.4850 post-dyeing. Furthermore, this research underscores improved colorfastness properties, including notable enhancements in light, wash, and rubbing fastness for both silk fabric and wool yarn. These findings underscore the efficacy of the proposed sustainable dyeing methods, offering valuable insights for eco-friendly textile production.


Assuntos
Carotenoides , Árvores , , Animais , Bixaceae , Têxteis , Sementes , Seda
3.
Nat Commun ; 15(1): 3289, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632231

RESUMO

Endowing textiles with perceptual function, similar to human skin, is crucial for the development of next-generation smart wearables. To date, the creation of perceptual textiles capable of sensing potential dangers and accurately pinpointing finger touch remains elusive. In this study, we present the design and fabrication of intelligent perceptual textiles capable of electrically responding to external dangers and precisely detecting human touch, based on conductive silk fibroin-based ionic hydrogel (SIH) fibers. These fibers possess excellent fracture strength (55 MPa), extensibility (530%), stable and good conductivity (0.45 S·m-1) due to oriented structures and ionic incorporation. We fabricated SIH fiber-based protective textiles that can respond to fire, water, and sharp objects, protecting robots from potential injuries. Additionally, we designed perceptual textiles that can specifically pinpoint finger touch, serving as convenient human-machine interfaces. Our work sheds new light on the design of next-generation smart wearables and the reshaping of human-machine interfaces.


Assuntos
Fibroínas , Seda , Humanos , Seda/química , Têxteis , Condutividade Elétrica , Fibroínas/química , Tato
4.
Transgenic Res ; 33(1-2): 21-33, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38573429

RESUMO

Plants can produce complex pharmaceutical and technical proteins. Spider silk proteins are one example of the latter and can be used, for example, as compounds for high-performance textiles or wound dressings. If genetically fused to elastin-like polypeptides (ELPs), the silk proteins can be reversibly precipitated from clarified plant extracts at moderate temperatures of ~ 30 °C together with salt concentrations > 1.5 M, which simplifies purification and thus reduces costs. However, the technologies developed around this mechanism rely on a repeated cycling between soluble and aggregated state to remove plant host cell impurities, which increase process time and buffer consumption. Additionally, ELPs are difficult to detect using conventional staining methods, which hinders the analysis of unit operation performance and process development. Here, we have first developed a surface plasmon resonance (SPR) spectroscopy-based assay to quantity ELP fusion proteins. Then we tested different filters to prepare clarified plant extract with > 50% recovery of spider silk ELP fusion proteins. Finally, we established a membrane-based purification method that does not require cycling between soluble and aggregated ELP state but operates similar to an ultrafiltration/diafiltration device. Using a data-driven design of experiments (DoE) approach to characterize the system of reversible ELP precipitation we found that membranes with pore sizes up to 1.2 µm and concentrations of 2-3 M sodium chloride facilitate step a recovery close to 100% and purities of > 90%. The system can thus be useful for the purification of ELP-tagged proteins produced in plants and other hosts.


Assuntos
60676 , Seda , Seda/genética , Proteínas de Artrópodes , Elastina/genética , Elastina/química , Elastina/metabolismo , Tabaco/genética , Proteínas Recombinantes de Fusão/genética
5.
Molecules ; 29(5)2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38474662

RESUMO

Tussah silk is one of the most widely used wild silks. It is usually dyed with acid dyes, despite the shortcoming of poor wet fastness. Reactive dyeing is a good solution to this problem. In our work, sulfatoethylsulfone (SES), sulfatoethylsulfone/monochlorotriazine (SES/MCT), monochlorotriazine (MCT), and bis(monochlorotriazine) (Bis(MCT)) dyes were used to dye tussah silk. All of these dyes showed lower exhaustion and fixation on tussah silk than on mulberry silk under alkaline conditions. Among them, SES dyes were more applicable, with a fixation of 70-85% (at 4%owf dye) at 90 °C when using sodium bicarbonate as an alkali. SES dyes also showed a rapid fixation speed. The dyeing of tussah silk required lower sodium bicarbonate dosage, the use of more neutral electrolytes, and a higher dye quantity to achieve deep effects compared to mulberry silk. Dyed tussah silk displayed lower apparent color depth and brilliance than dyed mulberry silk. The neutral boiling dyeing of tussah silk with SES dyes exhibited higher exhaustion, higher fixation (82-92% at 4%owf dye), and a slower fixation speed compared with alkaline dyeing. Furthermore, in this dyeing method, SES dyes showed higher and more efficient fixation on tussah silk than on mulberry silk. All dyed tussah silk had excellent color fastness to soaping.


Assuntos
Morus , Seda , Corantes , Bicarbonato de Sódio
6.
Biomater Sci ; 12(8): 2121-2135, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38456326

RESUMO

Natural polymer-based hydrogels have been widely applied in bone tissue engineering due to their excellent biocompatibility and outstanding ability of drug encapsulation. However, they have relatively weak mechanical properties and lack bioactivity. Hence, we developed a bioactive nanoparticle composite hydrogel by incorporating LAPONITE®, which is an osteo-inductive inorganic nanoparticle. The incorporation of the nanoparticle significantly enhanced its mechanical properties. In vitro evaluation indicated that the nanocomposite hydrogel could exhibit good biocompatibility. Besides, the nanocomposite hydrogel was proved to have excellent osteogenic ability with up-regulated expression of osteogenic markers such as type I collagen (COL-I), runt-related transcription factor-2 (Runx-2) and osteocalcin (OCN). Furthermore, the in vivo study confirmed that the composite nanocomposite hydrogel could significantly promote new bone formation, providing a prospective strategy for bone tissue regeneration.


Assuntos
Fibroínas , Nanopartículas , Hidrogéis , Nanogéis , Regeneração Óssea , Engenharia Tecidual , Seda
7.
Biomater Sci ; 12(8): 2067-2085, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38470831

RESUMO

The extracellular matrix (ECM) presents a framework for various biological cues and regulates homeostasis during both developing and mature stages of tissues. During development of cartilage, the ECM plays a critical role in endowing both biophysical and biochemical cues to the progenitor cells. Hence, designing microenvironments that recapitulate these biological cues as provided by the ECM during development may facilitate the engineering of cartilage tissue. In the present study, we fabricated an injectable interpenetrating hydrogel (IPN) system which serves as an artificial ECM and provides chondro-inductive niches for the differentiation of stem cells to chondrocytes. The hydrogel was designed to replicate the gradual stiffening (as a biophysical cue) and the presentation of growth factors (as a biochemical cue) as provided by the natural ECM of the tissue, thus exemplifying a biomimetic approach. This dynamic stiffening was achieved by incorporating silk fibroin, while the growth factor presentation was accomplished using sulfated-carboxymethyl cellulose. Silk fibroin and sulfated-carboxymethyl cellulose (s-CMC) were combined with tyraminated-carboxymethyl cellulose (t-CMC) and crosslinked using HRP/H2O2 to fabricate s-CMC/t-CMC/silk IPN hydrogels. Initially, the fabricated hydrogel imparted a soft microenvironment to promote chondrogenic differentiation, and with time it gradually stiffened to offer mechanical support to the joint. Additionally, the presence of s-CMC conferred the hydrogel with the property of sequestering cationic growth factors such as TGF-ß and allowing their prolonged presentation to the cells. More importantly, TGF-ß loaded in the developed hydrogel system remained active and induced chondrogenic differentiation of stem cells, resulting in the deposition of cartilage ECM components which was comparable to the hydrogels that were treated with TGF-ß provided through media. Overall, the developed hydrogel system acts as a reservoir of the necessary biological cues for cartilage regeneration and simultaneously provides mechanical support for load-bearing tissues such as cartilage.


Assuntos
Cartilagem Articular , Fibroínas , Engenharia Tecidual/métodos , Hidrogéis/química , Sulfatos , Carboximetilcelulose Sódica , Peróxido de Hidrogênio , Cartilagem , Seda , Fator de Crescimento Transformador beta , Tecidos Suporte/química , Condrogênese
8.
Sheng Wu Gong Cheng Xue Bao ; 40(3): 687-704, 2024 Mar 25.
Artigo em Chinês | MEDLINE | ID: mdl-38545971

RESUMO

Spider silk is a natural fiber known as "biosteel" with the strongest composite performance, such as high tensile strength and toughness. It is also equipped with excellent biocompatibility and shape memory ability, thus shows great potential in many fields such as biomedicine and tissue engineering. Spider silk is composed of macromolecular spidroin with rich structural diversity. The characteristics of the primary structure of natural spidroin, such as the high repeatability of amino acids in the core repetitive region, the high content of specific amino acids, the large molecular weight, and the high GC content of the spidroin gene, have brought great difficulties in heterologous expression. This review discusses focuses on the relationship between the featured motifs of the microcrystalline region in the repetitive unit of spidroin and its structure, as well as the spinning performance and the heterologous expression. The optimization design for the sequence of spidroin combined with heterologous expression strategy has greatly promoted the development of the biosynthesis of spider silk proteins. This review may facilitate the rational design and efficient synthesis of recombinant spidroin.


Assuntos
Fibroínas , Aranhas , Animais , Seda/genética , Seda/química , Fibroínas/genética , Fibroínas/química , Proteínas de Artrópodes , Materiais Biocompatíveis , Aminoácidos , Aranhas/genética
9.
Int J Mol Sci ; 25(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38542108

RESUMO

The increasing demand for innovative approaches in wound healing and skin regeneration has prompted extensive research into advanced biomaterials. This review focuses on showcasing the unique properties of sustainable silk-based particulate systems in promoting the controlled release of pharmaceuticals and bioactive agents in the context of wound healing and skin regeneration. Silk fibroin and sericin are derived from well-established silkworm production and constitute a unique biocompatible and biodegradable protein platform for the development of drug delivery systems. The controlled release of therapeutic compounds from silk-based particulate systems not only ensures optimal bioavailability but also addresses the challenges associated with conventional delivery methods. The multifaceted benefits of silk proteins, including their inherent biocompatibility, versatility, and sustainability, are explored in this review. Furthermore, the intricate mechanisms by which controlled drug release takes place from silk-based carriers are discussed.


Assuntos
Fibroínas , Seda , Seda/metabolismo , Preparações de Ação Retardada , Cicatrização , Pele/metabolismo , Materiais Biocompatíveis/uso terapêutico , Fibroínas/metabolismo
10.
Front Immunol ; 15: 1340405, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38426101

RESUMO

The inflammasome is a multiprotein complex critical for the innate immune response to injury. Inflammasome activation initiates healthy wound healing, but comorbidities with poor healing, including diabetes, exhibit pathologic, sustained activation with delayed resolution that prevents healing progression. In prior work, we reported the allosteric P2X7 antagonist A438079 inhibits extracellular ATP-evoked NLRP3 signaling by preventing ion flux, mitochondrial reactive oxygen species generation, NLRP3 assembly, mature IL-1ß release, and pyroptosis. However, the short half-life in vivo limits clinical translation of this promising molecule. Here, we develop a controlled release scaffold to deliver A438079 as an inflammasome-modulating wound dressing for applications in poorly healing wounds. We fabricated and characterized tunable thickness, long-lasting silk fibroin dressings and evaluated A438079 loading and release kinetics. We characterized A438079-loaded silk dressings in vitro by measuring IL-1ß release and inflammasome assembly by perinuclear ASC speck formation. We further evaluated the performance of A438079-loaded silk dressings in a full-thickness model of wound healing in genetically diabetic mice and observed acceleration of wound closure by 10 days post-wounding with reduced levels of IL-1ß at the wound edge. This work provides a proof-of-principle for translating pharmacologic inhibition of ATP-induced inflammation in diabetic wounds and represents a novel approach to therapeutically targeting a dysregulated mechanism in diabetic wound impairment.


Assuntos
Diabetes Mellitus Experimental , Inflamassomos , Piridinas , Tetrazóis , Camundongos , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR , Cicatrização , Bandagens , Seda , Trifosfato de Adenosina
11.
PLoS One ; 19(3): e0299385, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38478538

RESUMO

The Taihe Black-Bone silky fowl chicken (BB-sfc) is a renowned dietary and medicinal chicken globally recognized for its high nutritional and medicinal value. Compared to the local Black-Bone black-feathered chicken (BB-bfc), the Taihe silky fowl chicken has higher levels of amino acids, trace elements, and unsaturated fatty acids in their muscles, which offer anti-aging, anti-cancer, and immune enhancing benefits. Despite this, the unique nutritional components, genes, and proteins in Taihe silky fowl chicken muscles are largely unknown. Therefore, we performed a comprehensive transcriptome and proteome analysis of muscle development between BB-sfc and BB-bfc chickens using RNA-Seq and TMT-based quantitative proteomics methods. RNA-Seq analysis identified 286 up-regulated genes and 190 down-regulated genes in BB-sfc chickens, with oxidoreductase activity and electron transfer activity enriched in up-regulated genes, and phospholipid homeostasis and cholesterol transporter activity enriched in down-regulated genes. Proteome analysis revealed 186 significantly increased and 287 significantly decreased proteins in Taihe BB-sfc chicken muscles, primarily affecting mitochondrial function and oxidative phosphorylation, crucial for enhancing muscle antioxidant capacity. Integrated transcriptome and proteome analysis identified 6 overlapped up-regulated genes and 8 overlapped down-regulated genes in Taihe silky fowl chicken, related to improved muscle antioxidant status. Taken together, this research provides a comprehensive database of gene expression and protein information in Taihe Black-Bone silky fowl chicken muscles, aiding in fully exploring their unique economic value in the future.


Assuntos
Galinhas , Proteoma , Animais , Galinhas/genética , Proteoma/genética , Transcriptoma , Seda/genética , Antioxidantes , Músculos , China
12.
Zootaxa ; 5405(1): 116-130, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38480394

RESUMO

Taxonomic equivocality and complexity exist in the two species of Ceratopogonids, Forcipomyia (Microhelea) fuliginosa Meigen and Forcipomyia (Microhelea) esakiana Tokunaga. Incongruencies and inaccuracies in species identification restrict further biological and ecological studies on the host-ectoparasite association. Preferential landing and hemolymphophagy of F. fuliginosa and F. esakiana on Antheraea mylitta Drury larva were studied under field conditions. The silkworm A. mylitta is reared in the tasar sericulture industry, contributing 1466 metric tons (202122) of indigenous raw silk in India. Ectoparasitic behavior of the biting midges, F. fuliginosa, and F. esakiana is an increasing threat to the silkworm, necessitating proper identification. Intra and inter-variations of these two closely related species have been stated. Morphological-based identification of these species has been substantiated with COX1 molecular data. A Bayesian-modeled approach to reconstruct the dendrogram of the two species based on the COX1 sequences generated has been presented along with the referred sequences of F. fuliginosa from Genebank. The species F. esakiana is being reported for the first time from India, along with its ectoparasitic hemolymphophagous nature. The role of these insectivorous species in transmitting pathogens to the larvae of tasar silk needs further investigation.


Assuntos
Ceratopogonidae , Mariposas , Animais , Teorema de Bayes , Larva , Seda
13.
Molecules ; 29(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38474537

RESUMO

Spider silk protein, renowned for its excellent mechanical properties, biodegradability, chemical stability, and low immune and inflammatory response activation, consists of a core domain with a repeat sequence and non-repeating sequences at the N-terminal and C-terminal. In this review, we focus on the relationship between the silk structure and its mechanical properties, exploring the potential applications of spider silk materials in the detection of energetic materials.


Assuntos
Seda , Aranhas , Sequências Repetitivas de Ácido Nucleico , Seda/química , Animais
14.
J Evid Based Dent Pract ; 24(1): 101952, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38448126

RESUMO

BACKGROUND: In order to achieve uneventful and rapid healing of the tissues, a suture material should be biocompatible, easy to handle, sterile, and have good and uniform tensile strength. Hence, in the present study, characterization of the suture materials was done through a novel green chemistry approach using Punica granatum seed extract. MATERIALS AND METHODS: Ethanolic extract of P. granatum seed was prepared by dissolving 25 g of P. granatum seed powder with 100 mL of ethanol. The obtained extract was coated in silk and Vicryl suture material and was tested for its surface morphology (SEM), tensile strength, anti-microbial activity, biocompatibility, and wound healing potential. RESULTS: Silk and Vicryl sutures coated with P. granatum seed extract showed the uniform coating and deposition of extract with sustaining integrity. Vicryl suture coated with the extract had good tensile strength and antimicrobial activity. The in vitro scratch assay and biocompatibility test showed that the P. granatum seed extract had excellent wound healing potential and can be used without any effect on the viability of the normal cells. CONCLUSION: Within the limitations of the study it can be concluded that P. granatum seed extract coated Vicryl sutures had good tensile strength and anti-microbial activity. P. granatum seed extract also showed excellent biocompatibility and wound healing potential.


Assuntos
Punica granatum , Humanos , Projetos Piloto , Poliglactina 910 , Suturas , Seda , Etanol , Extratos Vegetais/farmacologia
15.
ACS Synth Biol ; 13(4): 1191-1204, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38536670

RESUMO

The presence of a hydration layer in humid and underwater environments challenges adhesive-substrate interactions and prevents effective bonding, which has become a significant obstacle to the development of adhesives in the industrial and biomedical fields. In this study, ultrahigh-molecular-weight (UHMW) silk-elastin-like proteins (SELP) with 3,4-dihydroxyphenylalanine (DOPA) converted from tyrosine residues by tyrosinase exhibited excellent adhesive properties on different interfaces, such as glass, aluminum, wood, polypropylene sheets, and pigskin, under both dry and wet conditions. Additionally, by incorporating trace amounts of cross-linking agents like Fe3+, NaIO4, and tris(hydroxymethyl) phosphine (THP), the mussel-inspired adhesives maintained a stable and excellent adhesion, broadening the conditions of application. Notably, the UHMW SELP adhesive exhibited remarkable underwater adhesion properties with a shear strength of 0.83 ± 0.17 MPa on glass. It also demonstrated good adhesion to biological tissues including the kidney, liver, heart, and lungs. In vitro cytocompatibility testing using L929 cells showed minimal toxicity, highlighting its potential application in the biomedical field. The sustainable, cytocompatible, cost-effective, and highly efficient adhesive provides valuable insights for the design and development of a new protein-based underwater adhesive for medical application.


Assuntos
Adesivos , Monofenol Mono-Oxigenase , Proteínas Recombinantes de Fusão , Adesivos/química , Elastina , Seda
16.
ACS Appl Bio Mater ; 7(4): 2389-2401, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38502100

RESUMO

Graphene-based nanomaterials, renowned for their outstanding electrical conductivity, have been extensively studied as electroconductive biomaterials (ECBs) for electrically stimulated tissue regeneration. However, using eco-friendly reducing agents like l-ascorbic acid (l-Aa) can result in lower conductive properties in these ECBs, limiting their full potential for smooth charge transfer in living tissues. Moreover, creating a flexible biomaterial scaffold using these materials that accurately mimics a specific tissue microarchitecture, such as nerves, poses additional challenges. To address these issues, this study developed a microfibrous scaffold of Bombyx mori (Bm) silk fibroin uniformly coated with graphene nanoplatelets (GNPs) through a vacuum coating method. The scaffold's electrical conductivity was optimized by varying the reduction period using l-Aa. The research systematically investigated how different reduction periods impact scaffold properties, focusing on electrical conductivity and its significance on electrically stimulated axonal growth in PC12 cells. Results showed that a 48 h reduction significantly increased surface electrical conductivity by 100-1000 times compared to a shorter or no reduction process. l-Aa contributed to stabilizing the reduced GNPs, demonstrated by a slow degradation profile and sustained conductivity even after 60 days in a proteolytic environment. ß (III) tubulin immunostaining of PC12 cells on varied silk:GNP scaffolds under pulsed electrical stimulation (ES, 50 Hz frequency, 1 ms pulse width, and amplitudes of 100 and 300 mV/cm) demonstrates accelerated axonal growth on scaffolds exhibiting higher conductivity. This is supported by upregulated intracellular Ca2+ dynamics immediately after ES on the scaffolds with higher conductivity, subjected to a prolonged reduction period. The study showcases a sustainable reduction approach using l-Aa in combination with natural Bm silk fibroin to create a highly conductive, mechanically robust, and stable silk:GNP-based aligned fibrous scaffold. These scaffolds hold promise for functional regeneration in electrically excitable tissues such as nerves, cardiac tissue, and muscles.


Assuntos
Bombyx , Fibroínas , Grafite , Ratos , Animais , Seda , Tecidos Suporte , Grafite/farmacologia , Fibroínas/farmacologia , Materiais Biocompatíveis/farmacologia , Condutividade Elétrica
17.
J Microbiol Methods ; 220: 106923, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38521504

RESUMO

BACKGROUND: Infections resulting from surgical procedures and wound closures continue to pose significant challenges in healthcare settings. To address this issue, the investigators have developed antibacterial non-resorbable braided silk sutures using in situ deposited silver nanoparticles (AgNPs) and investigated their efficacy in eradicating Staphylococcus aureus and Streptococcus mutans infections. METHODS: The braided silk sutures were modified through a simple and efficient in situ photoreduction method, resulting in the uniform distribution of AgNPs along the suture surface. The synthesized AgNPs were characterized using scanning electron microscopy (SEM), dynamic light scattering analysis (DLS) and Fourier Transform Infrared Spectroscopy analysis (FTIR) confirming their successful integration onto the silk sutures. The antibacterial activity of the nanoparticle coated sutures were compared and evaluated with non-coated braided silk sutures through in vitro assays against both S. aureus and S. mutans. RESULTS: The surface and cross-sectional analysis of the treated sutures revealed a uniform and homogeneous distribution of silver particles achieved through the photoreduction of silver solution. This observation confirms the successful coating of silver nanoparticles (AgNPs) on the sutures. The antimicrobial studies conducted, demonstrated significant reductions in bacterial colonies when exposed to the silver nanoparticle-coated sutures. Notably, the width of the inhibition zone surrounding the coated sutures remained consistently wide and stable for duration up to 7 days. This sustained and robust inhibitory effect against gram-positive bacteria, specifically S. aureus and S. mutans, serves as strong evidence of the antibacterial efficacy of the coated sutures. CONCLUSION: The coating of silk sutures with AgNPs provided a significant and effective antibacterial capacity to the surgical sutures, with this activity being sustained for a period of 7 days. This suggests that AgNPs-in situ photoreduction deposited sutures have the potential to effectively manage S. aureus and S. mutans infections.


Assuntos
Nanopartículas Metálicas , Prata , Prata/química , Staphylococcus aureus , Nanopartículas Metálicas/química , Streptococcus mutans , Estudos Transversais , Suturas/microbiologia , Antibacterianos/farmacologia , Seda/química , Seda/farmacologia , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Toxins (Basel) ; 16(3)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38535800

RESUMO

The oriental armyworm, Mythimna separata (Walker), an important migratory pest of maize and wheat, is posing a severe threat to maize production in Asian countries. As source areas of spring-summer emigratory populations, the control of M. separata in southwestern China is of great significance for East Asian maize production. To assess the toxicity of Bt maize against the pest, bioassays of Bt-(Cry1Ab+Vip3Aa) maize (event DBN3601T), Bt-Cry1Ab maize (event DBN9936), and Bt-Vip3Aa maize (event DBN9501) were conducted in Yunnan province of southwest China. There were significant differences in insecticidal activity between the three Bt maize events, and DBN3601T presented the highest insecticidal role. The results also indicated that the insecticidal effect of various Bt maize tissues took an order in leaf > kernel > silk, which is highly consistent with the expression amounts of Bt insecticidal protein in leaf (69.69 ± 1.18 µg/g), kernel (11.69 ± 0.75 µg/g), and silk (7.32 ± 0.31 µg/g). In field trials, all larval population densities, plant damage rates, and leaf damage levels of DBN3601T maize were significantly lower than the conventional maize. This research indicated that the DBN3601T event had a high control efficiency against M. separata and could be deployed in southwest China for the management of M. separata.


Assuntos
Inseticidas , Platelmintos , Animais , China , Zea mays , Spodoptera , Ásia , Seda
19.
Int J Mol Sci ; 25(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38542528

RESUMO

Spider silk has extraordinary mechanical properties, displaying high tensile strength, elasticity, and toughness. Given the high performance of natural fibers, one of the long-term goals of the silk community is to manufacture large-scale synthetic spider silk. This process requires vast quantities of recombinant proteins for wet-spinning applications. Attempts to synthesize large amounts of native size recombinant spidroins in diverse cell types have been unsuccessful. In these studies, we design and express recombinant miniature black widow MaSp1 spidroins in bacteria that incorporate the N-terminal and C-terminal domain (NTD and CTD), along with varying numbers of codon-optimized internal block repeats. Following spidroin overexpression, we perform quantitative analysis of the bacterial proteome to identify proteins associated with spidroin synthesis. Liquid chromatography with tandem mass spectrometry (LC MS/MS) reveals a list of molecular targets that are differentially expressed after enforced mini-spidroin production. This list included proteins involved in energy management, proteostasis, translation, cell wall biosynthesis, and oxidative stress. Taken together, the purpose of this study was to identify genes within the genome of Escherichia coli for molecular targeting to overcome bottlenecks that throttle spidroin overexpression in microorganisms.


Assuntos
Fibroínas , Aranhas , Animais , Fibroínas/química , Proteômica , Espectrometria de Massas em Tandem , Seda/química , Proteínas Recombinantes/química , Bactérias , Aranhas/genética
20.
Int J Biol Macromol ; 265(Pt 1): 130956, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38499118

RESUMO

This study explored the valorisation of silkworm by-product, a major by-product of the silk industry (sericulture), which amounts to 16 million tonnes annually. The focus was on transforming waste into energy resources through pyrolysis under CO2 conditions. In one-stage pyrolysis, the evolution of syngas under N2 was found to be comparable to that under CO2. A notable allocation of carbon to biocrude rather than syngas was observed. The two-stage pyrolysis resulted in increased syngas production. However, achieving a homogeneous reaction between CO2 and the volatiles liberated from silkworm byproduct proved challenging. Indeed, the reaction kinetics governing CO2 reactivity was not fast although the temperature windows of the reaction were aligned in the two-stage pyrolysis. To address this issue, pyrolysis was performed using a Ni-based catalyst to expedite the reaction kinetics. Consequently, syngas formation, particularly CO formation, was significantly enhanced under CO2 conditions compared to that under N2 conditions. The syngas yield under CO2 was 36.42 wt% which was 2-fold higher than that of N2. This suggested the potential of CO2 altering the carbon distribution from biocrude to syngas. This strategy would contribute to the establishment of sustainable production of silk by converting sericulture by-product into energy/chemical resources.


Assuntos
Bombyx , Dióxido de Carbono , Animais , Carbono , Temperatura , Seda
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