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Recently, the desire for a safe and effective method for skin whitening has been growing in the cosmetics industry. Commonly used tyrosinase-inhibiting chemical reagents exhibit side effects. Thus, recent studies have focused on performing melanin decolorization with enzymes as an alternative due to the low toxicity of enzymes and their ability to decolorize melanin selectively. Herein, 10 different isozymes were expressed as recombinant lignin peroxidases (LiPs) from Phanerochaete chrysosporium (PcLiPs), and PcLiP isozyme 4 (PcLiP04) was selected due to its high stability and activity at pH 5.5 and 37 °C, which is close to human skin conditions. In vitro melanin decolorization results indicated that PcLiP04 exhibited at least 2.9-fold higher efficiency than that of well-known lignin peroxidase (PcLiP01) in a typical human skin-mimicking environment. The interaction force between melanin films measured by a surface forces apparatus (SFA) revealed that the decolorization of melanin by PcLiP04 harbors a disrupted structure, possibly interrupting π-π stacking and/or hydrogen bonds. In addition, a 3D reconstructed human pigmented epidermis skin model showed a decrease in melanin area to 59.8% using PcLiP04, which suggests that PcLiP04 exhibits a strong potential for skin whitening.
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Melaninas , Phanerochaete , Humanos , Peroxidases , Pele , Epiderme , LigninaRESUMO
Periodontitis is a disease characterized by tooth-associated microbial biofilms that drive chronic inflammation and destruction of periodontal-supporting tissues. In some individuals, disease progression can lead to tooth loss. A similar condition can occur around dental implants in the form of peri-implantitis. The immune response to bacterial challenges is not only influenced by genetic factors, but also by environmental factors. Epigenetics involves the study of gene function independent of changes to the DNA sequence and its associated proteins, and represents a critical link between genetic and environmental factors. Epigenetic modifications have been shown to contribute to the progression of several diseases, including chronic inflammatory diseases like periodontitis and peri-implantitis. This review aims to present the latest findings on epigenetic influences on periodontitis and to discuss potential mechanisms that may influence peri-implantitis, given the paucity of information currently available.
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Implantes Dentários , Peri-Implantite , Periodontite , Perda de Dente , Implantes Dentários/efeitos adversos , Epigênese Genética/genética , Humanos , Peri-Implantite/genética , Periodontite/genética , Perda de Dente/complicaçõesRESUMO
The development of a strategy to investigate interfacial phenomena at lipid membranes is practically useful because most essential biomolecular interactions occur at cell membranes. In this study, a colorimetric method based on cysteine-encapsulated liposomes was examined using gold nanoparticles as a probe to provide a platform to report an enzymatic activity at lipid membranes. The cysteine-encapsulated liposomes were prepared with varying ratios of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and cholesterol through the hydration of lipid films and extrusions in the presence of cysteine. The size, composition, and stability of resulting liposomes were analyzed by scanning electron microscopy (SEM), dynamic light scattering (DLS), nuclear magnetic resonance (NMR) spectroscopy, and UV-vis spectrophotometry. The results showed that the increased cholesterol content improved the stability of liposomes, and the liposomes were formulated with 60 mol % cholesterol for the subsequent experiments. Triton X-100 was tested to disrupt the lipid membranes to release the encapsulated cysteine from the liposomes. Cysteine can induce the aggregation of gold nanoparticles accompanying a color change, and the colorimetric response of gold nanoparticles to the released cysteine was investigated in various media. Except in buffer solutions at around pH 5, the cysteine-encapsulated liposomes showed the color change of gold nanoparticles only after being incubated with Triton X-100. Finally, the cysteine-encapsulated liposomal platform was tested to report the enzymatic activity of phospholipase A2 that hydrolyzes phospholipids in the membrane. The hydrolysis of phospholipids triggered the release of cysteine from the liposomes, and the released cysteine was successfully detected by monitoring the distinct red-to-blue color change of gold nanoparticles. The presence of phospholipase A2 was also confirmed by the appearance of a peak around 690 nm in the UV-vis spectra, which is caused by the cysteine-induced aggregation of gold nanoparticles. The results demonstrated that the cysteine-encapsulated liposome has the potential to be used to investigate biological interactions occurring at lipid membranes.
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Lipossomos , Nanopartículas Metálicas , Colesterol , Cisteína , Dimiristoilfosfatidilcolina , Ouro/química , Lipossomos/química , Nanopartículas Metálicas/química , Octoxinol , Fosfolipases , Fosfolipídeos , FosforilcolinaRESUMO
Rice husk is one of the most abundant biomass resources in the world, yet it is not effectively used. This study focuses on the sustainably rice-husk-extracted lignin, nano-lignin (n-Lignin), lignin-capped silver nanoparticles (LCSN), n-Lignin-capped silver nanoparticles (n-LCSN), and lignin-capped silica-silver nanoparticles (LCSSN), and using them for antibacterial activities. The final n-Lignin-based products had a sphere-like structure, of which the size varied between 50 and 80 nm. We found that while n-Lignin and lignin were less effective against Escherichia coli than against Staphylococcus aureus, n-Lignin/lignin-based hybrid materials, i.e., n-LCSN, LCSN, and LCSSN, were better against E. coli than against S. aureus. Interestingly, the antimicrobial behaviors of n-LCSNs could be further improved by decreasing the size of n-Lignin. Considering the facile, sustainable, and eco-friendly method that we have developed here, it is promising to use n-Lignin/lignin-based materials as highly efficient antimicrobials without environmental concerns.
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Nanopartículas Metálicas , Prata , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli , Lignina/química , Lignina/farmacologia , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Dióxido de Silício , Prata/química , Prata/farmacologia , Staphylococcus aureusRESUMO
Dysbiosis of the oral microbiome is associated with a variety of oral and systemic diseases, including periodontal disease. Oral dysbiosis in periodontal disease leads to an exacerbated host immune response that induces progressive periodontal tissue destruction and ultimately tooth loss. To counter the disease-associated dysbiosis of the oral cavity, strategies have been proposed to reestablish a "healthy" microbiome via the use of probiotics. This study reviews the literature on the use of probiotics for modifying the oral microbial composition toward a beneficial state that might alleviate disease progression. Four in vitro and 10 preclinical studies were included in the analysis, and these studies explored the effects of probiotics on cultured biofilm growth and bacterial gene expressions, as well as modulation of the host response to inflammation. The current molecular findings on probiotics provide fundamental evidence for further clinical research for the use of probiotics in periodontal therapy. They also point out an important caveat: Changing the biofilm composition might alter the normal oral flora that is beneficial and/or critical for oral health.
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Microbiota , Doenças Periodontais , Probióticos , Disbiose , Humanos , Doenças Periodontais/terapia , Probióticos/uso terapêuticoRESUMO
The effects of probiotic supplementation on systemic health and gastrointestinal diseases have been investigated in numerous studies. The aim of this review is to provide an overview of probiotics and their effects on periodontal health. Probiotics show beneficial effects as adjunctive therapeutics and as stand-alone agents in the treatment and prevention of gingivitis as well as specific clinical parameters of periodontitis. This review focuses on the clinical and microbiological aspects of probiotics in the context of health, gingivitis, and periodontitis. In addition, a special focus on nisin-producing probiotics and nisin itself showcase their significant potential for oral and systemic use.
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Gengivite , Nisina , Periodontite , Probióticos , HumanosRESUMO
While conducting sentinel surveillance of hand, foot, and mouth disease (HFMD) in Vietnam, we found a sudden increase in the prevalence of coxsackievirus A10 (CV-A10) in 2016 and CV-A2 and CV-A4 in 2017, the emergence of which has been reported recently to be associated with various clinical manifestations in other countries. However, there have been only a limited number of molecular studies on those serotypes, with none being conducted in Vietnam. Therefore, we sequenced the entire VP1 genes of CV-A10, CV-A4, and CV-A2 strains associated with HFMD in Vietnam between 2012 and 2017. Phylogenetic analysis revealed a trend of endemic circulation of Vietnamese CV-A10, CV-A4, and CV-A2 strains and the emergence of thus-far undescribed HFMD-causing lineages of CV-A4 and CV-A2. The Vietnamese CV-A10 strains belonged to a genotype comprising isolates from patients with HFMD from several other countries; however, most of the Vietnamese strains were grouped into a local lineage. Recently, emerging CV-A4 strains in Vietnam were grouped into a unique lineage within a genotype comprising strains isolated from patients with acute flaccid paralysis from various countries. New substitutions were detected in the putative BC and HI loops in the Vietnamese CV-A4 strains. Except for one strain, Vietnamese CV-A2 isolates were grouped into a unique lineage of a genotype that includes strains from various countries that are associated with other clinical manifestations. Enhanced surveillance is required to monitor their spread and to specify their roles as etiological agents of HFMD or "HFMD-like" diseases, especially for CV-A4 and CV-A2. Further studies including whole-genome sequencing should be conducted to fully understand the evolutionary changes occurring in these newly emerging strains.
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Proteínas do Capsídeo/genética , Enterovirus Humano A/isolamento & purificação , Doença de Mão, Pé e Boca/virologia , Doenças Transmissíveis Emergentes/epidemiologia , Doenças Transmissíveis Emergentes/virologia , Surtos de Doenças , Enterovirus Humano A/classificação , Enterovirus Humano A/genética , Genoma Viral , Genótipo , Doença de Mão, Pé e Boca/epidemiologia , Humanos , Filogenia , Vigilância de Evento Sentinela , Vietnã/epidemiologiaRESUMO
The reconstruction of alveolar bone defects associated with teeth and dental implants remains a clinical challenge in the treatment of patients affected by disease or injury of the alveolus. The aim of this review was to provide an overview on advances made in the use of personalized scaffolding technologies coupled with biologics, cells and gene therapies that offer future clinical applications for the treatment of patients requiring periodontal and alveolar bone regeneration. Over the past decade, advancements in three-dimensional (3D) imaging acquisition technologies such as cone-beam computed tomography (CBCT) and precise scaffold fabrication methods such as 3D bioprinting have resulted in personalized scaffolding constructs based on individual patient-specific anatomical data. Furthermore, 'fiber-guiding' scaffold designs utilize topographical cues to guide ligamentous fibers to form in orientation towards the root surface to improve tooth support. Therefore, a topic-focused literature search was conducted looking into fiber-guiding and image-based scaffolds and their associated clinical applications.
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Regeneração Óssea , Medicina Regenerativa , Tomografia Computadorizada de Feixe Cônico , Humanos , Engenharia TecidualRESUMO
PURPOSE: To assess morbidity and mortality associated with oral and maxillofacial surgery procedures requiring general anesthesia among children with aspiration tendency requiring enteral feeding. MATERIAL AND METHODS: A retrospective chart review was conducted of children surgically treated under general anesthesia by the oral and maxillofacial surgery service at the Hospital for Sick Children in Toronto, Canada. Medical and dental records over a 9-year period (January 1, 2000 to January 1, 2010) were reviewed. Data were collected on demographics, primary illness, coexisting medical conditions, procedures performed, medications administered, type of airway management used, duration of general anesthesia, American Society of Anesthesiologists' physical status classification and adverse events. RESULTS: During the period reviewed, 28 children underwent 35 oral and maxillofacial surgery procedures under general anesthesia. The mean patient age was 12 years (range 4-17 years). No deaths occurred. Of the 35 surgeries, 10 (29%) were associated with at least 1adverse event. Adverse events included 1incident of respiratory distress, 2incidents of fever, 5incidents of bleeding, 1incident of seizure and 4incidents of oxygen saturation below 90% for more than 30s. CONCLUSIONS: Children with a history of aspiration tendency that necessitates enteral feeding, who undergo oral and maxillofacial surgery under general anesthesia, are at increased risk of morbidity. Before initiating treatment, the surgeon and parents or guardians of such children should carefully consider these risks compared with the anticipated benefit of surgery.
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Anestesia Geral , Procedimentos Cirúrgicos Ortognáticos/efeitos adversos , Adolescente , Canadá , Criança , Pré-Escolar , Nutrição Enteral , Feminino , Humanos , Masculino , Estudos Retrospectivos , Cirurgia BucalRESUMO
BACKGROUND: Recent developments in addressing dental aesthetic concerns, encompassing issues like teeth discoloration and halitosis, underscore the demand for safer alternative solutions. PURPOSE: This study aims to confirm the effects of lactic acid bacteria (LAB) from kimchi on artificial teeth bleaching and their potential impact in terms of preventing halitosis-related bacteria. MATERIALS AND METHODS: To evaluate the antimicrobial effects against oral pathogens, disc diffusion tests and broth microdilution methods were used. Additionally, crystal violet analysis was performed to confirm the biofilm inhibition effect. The bleaching effects on stained artificial teeth were analyzed using the CIEDE2000 colorimetric method. Statistical analyses were performed using GraphPad Prism 9 with one-way and two-way ANOVA, with the significance level set at α < 0.05. RESULTS: The strain THK-30, isolated from kimchi, exhibited antibacterial activity against Streptococcus mutans, Porphyromonas gingivalis, and Fusobacterium nucleatum, and was identified as Pediococcus inopinatus. Moreover, THK-30 showed a synergistic antibacterial effect against Gram-negative oral pathogens with 8% sodium hexametaphosphate (SHMP). In the stained artificial teeth bleaching test and artificial teeth biofilm inhibition test, the cell-free supernatant of THK-30 displayed significant teeth bleaching effects and caused the inhibition of biofilm formation, both independently and in combination with SHMP 8%. CONCLUSIONS: This study has demonstrated the potential applicability of LAB in teeth discoloration and halitosis. These findings are poised to provide a foundation for the development of research pertaining to the control of oral bacteria.
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Background: Different restoration materials have different optical characteristics that influence the intraoral scanner's (IOS) image accuracy. The purpose of this in-vitro investigation was to investigate how composite translucency affected the accuracy of IOS. Material and Methods: GC G-aenial Universal Injectable JE composite plates were used for the study at 3 thicknesses (1-2-3mm). A lab scanner (3Shape E1) obtained 1 reference scan, whereas IOS (Trios3) was used to conduct 10 experimental scans per group. After 3D superimposition, deviation values were used to assess the accuracy (trueness and precision) outcomes for the corresponding groups. Using an LS170 V2.0 colorimeter, the translucency parameter (TP) of the plates was determined from L*a*b* values of CIELAB color space. Results: The composite translucency resulted in a decrease in the scale of digital impressions. The 1mm group had the largest scale reduction (0.02mm) significantly, followed by the 2mm and 3mm groups (0.01mm). No difference was found in mean precision. The colorimeter detects the L*a*b* values and showed that 1mm composite plate expressed the highest TP value, then 2mm and 3mm groups (28.90, 14.26 and 6.49 respectively). The thinner composite, the higher translucency and TP were highly positively correlated to IOS trueness of composite plates. Conclusions: Composite translucency has an impact on optical impression accuracy. In correlation, the optical impression becomes less accurate the more translucent the composite is. This implies that in the digital process, the dentist should specify the appropriate optical properties of composite materials concerning both their mechanical and aesthetic qualities. Key words:Accuracy, translucency, resin composite, digital dentistry, intraoral-scanner.
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BACKGROUND AND PURPOSE: The soft-tissue layer and facial skeleton influence the harmony and equilibrium of the face. The evaluation of the patient's structural and soft-tissue features is one of the most crucial steps in preparing for the diagnosis and treatment of oral-maxillofacial orthodontics. Clinicians can intervene with the proper treatment at the proper time to achieve the best results by being aware of the traits and variations of soft tissue at various developmental stages and in various races. To obtain a consistent treatment result in terms of function and aesthetically pleasing results, patients, and forecast, the growth that may take place after the orthopedic therapy has concluded. OBJECTIVE: To examine the soft-tissue features of the oral-maxillofacial area in Vietnamese adults (aged 18-25 years) by evaluating cephalometric radiographs. MATERIALS AND METHODS: In a cross-sectional descriptive study, 85 students from Can Tho University of Medicine and Pharmacy took part. Students' lateral cephalograms were taken in compliance with the sample requirements. RESULTS: Men's lip protrusion (4.30 ± 0.71) was higher than women's (3.88 ± 0.97) (P = 0.024 <.05) and men's (-4.88 ± 0.93) chin lip groove depth was higher than women's (-4.24 ± 0.93) (P = 0.002), both with a P value of. 05. CONCLUSIONS: The study identified a statistically significant difference in the protrusion of the top lip and the depth of the cleft lip between the male and female, demonstrating that the soft-tissue features of Vietnamese students were distinct from those of other races.
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Biofilm formation of Listeria monocytogenes in food processing environments cause potential source of cross-contamination to foodstuffs; hence, the control of biofilm is currently addressed to find effective solutions for preventing biofilm formation or eliminating the established one. Forty-five strains of Listeria monocytogenes isolated from Pangasius fish-processing plants were studied for their capability to form a biofilm on 96-well microtiter plate by using the conventional crystal violet staining. Additionally, the inhibitory effect of biofilm formation by food additives including monascus pigment and ε-polylysine was examined. The average OD value showing biofilm mass of all 45 strains L. monocytogenes increased with an increasing temperature and time (p < 0.05). Monascus pigment and ε-polylysine significantly decreased biofilm formation by 80 ± 5.5% and 20 ± 5.9%, respectively, at the tested concentration (p < 0.05) Further, the effects of lysozyme (0.1 mg/mL) alone or in combination with slightly acidic hypochlorous water (SAHW) with 40 mg/L available chlorine or sodium hypochlorite (NaOCl) with 100 mg/L available chlorine against 7-d established biofilm of L. monocytogenes were investigated. The results indicated that slightly acidic hypochlorous water alone exhibited significant antibacterial activity (p < 0.05), decreasing the viable count by 5.2 ± 0.5 log CFU/mL. It seems that sequential treatment of lysozyme and SAHW showed an additional efficacy against biofilm of L. monocytogenes on polystyrene plate surface, reducing 70% of biomass of biofilm and 7.6 ± 0.3 log of biofilm viable cells (p < 0.05). Additionally, SAHW exhibited greater bactericidal activity against viable biofilm cells than NaOCl did. This result reveals that SAHW is a promising disinfectant agent against L. monocytogenes and the potential alternative to NaOCl in practice.
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Peixes-Gato , Listeria monocytogenes , Animais , Muramidase/farmacologia , Cloro/farmacologia , Polilisina/farmacologia , Aço Inoxidável , Biofilmes , Água/farmacologia , Contagem de Colônia MicrobianaRESUMO
Antibacterial materials have been developed for a long time but bacteria adapt very quickly and become resistant to these materials. This study focuses on the synthesis of a hybrid material system from lignin and silver/silica nanoparticles (Lig@Ag/SiO2 NPs) which were used against bacteria including Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) and inhibited the growth of the fungal Aspergillus flavus (A. flavus). The results showed that the spherical diameter of Lig@Ag/SiO2 NPs has narrow Gaussian distribution with a range from 15 nm to 40 nm in diameter. Moreover, there was no growth of E. coli in samples containing Lig@Ag/SiO2 NPs during 72-h incubation while colonies of S. aureus were only observed at high concentrations (106 CFU/mL) although both species of bacteria were able to thrive even at low bacterial concentration when they were exposed to Ag/SiO2 or lignin. For fungal resistance results, Lig@Ag/SiO2 NPs not only reduced mycelial growth but also inhibited sporulation in A. flavus, leading to decreasing the spreading of spores into the environment. This result represents a highly effective fungal growth inhibition of Lig@Ag/SiO2 NPs compared to lignin or Ag/SiO2, which could not inhibit the growth of sporulation.
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Nanopartículas Metálicas , Nanopartículas , Oryza , Antifúngicos/farmacologia , Staphylococcus aureus , Dióxido de Silício/farmacologia , Lignina/farmacologia , Escherichia coli , Antibacterianos/farmacologia , BactériasRESUMO
A primary molar dental abscess was implicated as the cause of a brain abscess in an 11-year-old boy. This case report describes the neurological signs and symptoms, and acute management of a brain abscess in a child. A brain abscess is provisionally diagnosed from the patient's medical history, as well as the presence of signs and symptoms such as fever, headache, nausea, vomiting, focal neurological deficit, altered mentation, speech alterations, papillary edema, and neck stiffness or seizures. A definitive diagnosis of brain abscess is confirmed through imaging. The dental source of infection is identified by the exclusion of more probable foci such as the ears, heart, lungs, eyes or sinuses.
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Abscesso Encefálico/etiologia , Infecção Focal Dentária/complicações , Dente Molar , Abscesso Encefálico/diagnóstico , Abscesso Encefálico/microbiologia , Abscesso Encefálico/cirurgia , Criança , Craniotomia , Diagnóstico Diferencial , Infecção Focal Dentária/diagnóstico , Infecção Focal Dentária/microbiologia , Infecção Focal Dentária/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Extração DentáriaRESUMO
The rapid evolution of 3D bioprinting technique, very few biomaterials have been studied and utilised as ink solutions to produce structures. In this work, a polymeric nanocomposite hydrogel-based ink solution was developed using boron nitride nanotubes (BNNTs) reinforced gelatin for 3D bioprinting of scaffolds. The ink solutions and printed scaffolds were characterised for their printability, mechanical, thermal, water uptake, and biological properties (cell viability and inflammation). The viscoelastic behaviour of the scaffolds indicated the increase in storage modulus with an increase in BNNTs composition. Additionally, the compressive strength of the scaffolds increased from 9.43 ± 1.3 kPa to 30.09 ± 1.5 kPa with the addition of BNNTs. Similarly, the thermal stability of the scaffolds enhanced with an increase in BNNTs composition. Furthermore, the scaffolds with a higher concentration of BNNTs displayed resilience in cell culture media at 37 °C for up to 14 days compared with pure gelatin scaffolds. The cell viability results showed a decreased viability rate with an increased concentration of BNNTs scaffolds. However, BNNTs incubated with cells did not display cytokine inflammation. Therefore, this work provides a potential hydrogel-based ink solution for 3D bioprinting of biomimetic tissue constructs with adequate structural stability for a wide range of tissue engineering and regenerative medicine applications.
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Bioimpressão , Nanotubos , Materiais Biocompatíveis/química , Bioimpressão/métodos , Compostos de Boro , Citocinas , Gelatina/química , Humanos , Hidrogéis/química , Inflamação , Tinta , Nanogéis , Engenharia Tecidual/métodos , Alicerces Teciduais/química , ÁguaRESUMO
Solar hydrogen production is one of the ultimate technologies needed to realize a carbon-neutral, sustainable society. However, an energy-intensive water oxidation half-reaction together with the poor performance of conventional inorganic photocatalysts have been big hurdles for practical solar hydrogen production. Here we present a photoelectrochemical cell with a record high photocurrent density of 19.8 mA cm-2 for hydrogen production by utilizing a high-performance organic-inorganic halide perovskite as a panchromatic absorber and lignocellulosic biomass as an alternative source of electrons working at lower potentials. In addition, value-added chemicals such as vanillin and acetovanillone are produced via the selective depolymerization of lignin in lignocellulosic biomass while cellulose remains close to intact for further utilization. This study paves the way to improve solar hydrogen productivity and simultaneously realize the effective use of lignocellulosic biomass.
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Celulose , Lignina , Biomassa , Compostos de Cálcio , Carbono , Hidrogênio , Óxidos , Titânio , ÁguaRESUMO
Lignin is a major component of lignocellulosic biomass. Although it is highly recalcitrant to break down, it is a very abundant natural source of valuable aromatic carbons. Thus, the effective valorisation of lignin is crucial for realising a sustainable biorefinery chain. Here, we report a compartmented photo-electro-biochemical system for unassisted, selective, and stable lignin valorisation, in which a TiO2 photocatalyst, an atomically dispersed Co-based electrocatalyst, and a biocatalyst (lignin peroxidase isozyme H8, horseradish peroxidase) are integrated, such that each system is separated using Nafion and cellulose membranes. This cell design enables lignin valorisation upon irradiation with sunlight without the need for any additional bias or sacrificial agent and allows the protection of the biocatalyst from enzyme-damaging elements, such as reactive radicals, gas bubbles, and light. The photo-electro-biochemical system is able to catalyse lignin depolymerisation with a 98.7% selectivity and polymerisation with a 73.3% yield using coniferyl alcohol, a lignin monomer.
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Fontes de Energia Bioelétrica , Lignina/química , Fotoquímica , Luz Solar , Biopolímeros/biossíntese , Reatores Biológicos , Dimerização , Peróxido de Hidrogênio/análise , PolimerizaçãoRESUMO
TEMPO-oxidized cellulose nanofiber (TOCNF) is a natural material with many promising properties, including biocompatibility and degradability. In this study, we integrated TOCNF at different concentrations (0.2, 0.4, 0.6, 0.8% w/v) with chitosan (CS) and created a thermosensitive injectable hydrogel intended for biomedical applications. These hydrogels can undergo sol-gel transition at body temperature through interactions between chitosan and ß-glycerophosphate. The addition of TOCNF resulted in faster gelation time and increased porosity. These hydrogels with TOCNF showed improved biocompatibility both in vitro and in vivo compared to CS hydrogel. Both MC3T3-E1 pre-osteoblast cells and L929 fibroblast cells showed biocompatibility towards CS/TOCNF 0.4. After 7days of implantation, initial inflammatory response to CS/TOCNF 0.4 was found. Such response was significantly subsided within 14days. Cell infiltration within the hydrogel was also prominent, showing anti-inflammatory or wound healing (M2) macrophage at 14days after implantation. These results showed that the addition of TOCNF could significantly improve the biocompatibility of CS hydrogel as a biomaterial for biomedical application.
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Materiais Biocompatíveis/química , Celulose/análogos & derivados , Quitosana/análogos & derivados , Hidrogéis/química , Nanofibras/química , Células 3T3 , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/efeitos adversos , Hidrogéis/administração & dosagem , Hidrogéis/efeitos adversos , Injeções , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Osteoblastos/efeitos dos fármacos , Piperidinas/química , Ratos , Ratos Sprague-Dawley , CicatrizaçãoRESUMO
BACKGROUND: Tunnel technique (TUN) has recently gained popularity among clinicians for its promising clinical and esthetic results in treating gingival recession (GR) defects. However, evidence regarding the efficacy of the TUN is not yet conclusive. Therefore, the aim of the present systematic review and meta-analysis was to investigate the predictability of TUN and its comparison to the coronally advanced flap (CAF) procedure. METHODS: A literature search on PubMed, Cochrane libraries, EMBASE, and hand-searched journals through November 2017 was conducted to identify clinical studies investigating TUN for root coverage procedures. Only randomized controlled trials (RCTs) were considered for the meta-analysis comparing TUN to CAF. RESULTS: A total of 20 articles were included in the systematic review and six in the meta-analysis. The overall calculated mean root coverage (mRC) of TUN for localized and multiple GR defects was 82.75 ± 19.7% and 87.87 ± 16.45%, respectively. Superior results were found in maxillary and in Miller Class I and II GR defects. TUN outcomes may have been enhanced by split-thickness flap preparation and microsurgical approach. TUN and CAF had comparable mRC, complete root coverage (CRC), keratinized tissue gain, and root coverage esthetic score when varying combinations of graft material were evaluated. However, CAF demonstrated superior outcomes to TUN when the same graft (connective tissue or acellular dermal matrix) was used in both techniques. CONCLUSIONS: TUN is an effective procedure in treating localized and multiple GR defects. Limited evidence is available comparing TUN to CAF; however, CAF seemed to be associated with higher percentage of CRC than was TUN when the same grafts (connective tissue or acellular dermal matrix) were used in both techniques.