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1.
Plant Cell ; 35(12): 4383-4404, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37738159

RESUMO

The elimination of seed shattering was a key step in rice (Oryza sativa) domestication. In this paper, we show that increasing the gibberellic acid (GA) content or response in the abscission region enhanced seed shattering in rice. We demonstrate that SLENDER RICE1 (SLR1), the key repressor of GA signaling, could physically interact with the rice seed shattering-related transcription factors quantitative trait locus of seed shattering on chromosome 1 (qSH1), O. sativa HOMEOBOX 15 (OSH15), and SUPERNUMERARY BRACT (SNB). Importantly, these physical interactions interfered with the direct binding of these three regulators to the lignin biosynthesis gene 4-COUMARATE: COENZYME A LIGASE 3 (4CL3), thereby derepressing its expression. Derepression of 4CL3 led to increased lignin deposition in the abscission region, causing reduced rice seed shattering. Importantly, we also show that modulating GA content could alter the degree of seed shattering to increase harvest efficiency. Our results reveal that the "Green Revolution" phytohormone GA is important for regulating rice seed shattering, and we provide an applicable breeding strategy for high-efficiency rice harvesting.


Assuntos
Oryza , Oryza/genética , Oryza/metabolismo , Lignina/metabolismo , Giberelinas/metabolismo , Sementes/genética , Sementes/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
2.
J Nanobiotechnology ; 22(1): 336, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38880905

RESUMO

Oxygen is necessary for life and plays a key pivotal in maintaining normal physiological functions and treat of diseases. Hemoglobin-based oxygen carriers (HBOCs) have been studied and developed as a replacement for red blood cells (RBCs) in oxygen transport due to their similar oxygen-carrying capacities. However, applications of HBOCs are hindered by vasoactivity, oxidative toxicity, and a relatively short circulatory half-life. With advancements in nanotechnology, Hb encapsulation, absorption, bioconjugation, entrapment, and attachment to nanomaterials have been used to prepare nanomaterial-related HBOCs to address these challenges and pend their application in several biomedical and therapeutic contexts. This review focuses on the progress of this class of nanomaterial-related HBOCs in the fields of hemorrhagic shock, ischemic stroke, cancer, and wound healing, and speculates on future research directions. The advancements in nanomaterial-related HBOCs are expected to lead significant breakthroughs in blood substitutes, enabling their widespread use in the treatment of clinical diseases.


Assuntos
Substitutos Sanguíneos , Hemoglobinas , Lipossomos , Nanoestruturas , Oxigênio , Humanos , Hemoglobinas/química , Hemoglobinas/metabolismo , Substitutos Sanguíneos/química , Oxigênio/química , Animais , Nanoestruturas/química , Lipossomos/química , Nanocápsulas/química , Cicatrização/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Choque Hemorrágico/tratamento farmacológico
3.
J Environ Manage ; 341: 118022, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37150166

RESUMO

Two novel and eco-friendly redox mediators (RMs), magnetic oxidative vanillin (MOV) and magnetic oxidative syringaldehyde (MOS), both derived from lignin, were prepared to improve the decolorization of the methyl orange (MO) dye. The Decolorization Efficiency (DE) of MO in the batch experiments with MOV and MOS were increased by more than 60% and 22%, respectively, when compared to the control experiment without magnetic RMs. Moreover, the two magnetic RMs could maintain stable DE of MO in sequenced batch reactors (SBRs), and negligible leaching of the oxidized lignin monomers was observed under various environmental conditions. Density Function Theory (DFT) calculations were used to propose three potential biodegradation mechanisms for azo dyes, and the key intermediates were confirmed using high-performance liquid chromatography. This study proposed a feasible strategy for functional utilization of lignin resource, as well as a practical method for effectively treating azo dye-containing wastewater.


Assuntos
Corantes , Lignina , Corantes/química , Elétrons , Compostos Azo/química , Biodegradação Ambiental , Aceleração
4.
J Child Psychol Psychiatry ; 61(4): 459-469, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31471912

RESUMO

BACKGROUND: Impaired attention to faces of interactive partners is a marker for autism spectrum disorder (ASD) in early childhood. However, it is unclear whether children with ASD avoid faces or find them less salient and whether the phenomenon is linked with the presence of eye contact or speech. METHODS: We investigated the impacts of speech (SP) and direct gaze (DG) on attention to faces in 22-month-old toddlers with ASD (n = 50) and typically developing controls (TD, n = 47) using the Selective Social Attention 2.0 (SSA 2.0) task. The task consisted of four conditions where the presence (+) and absence (-) of DG and SP were systematically manipulated. The severity of autism symptoms, and verbal and nonverbal skills were characterized concurrently with eye tracking at 22.4 (SD = 3.2) months and prospectively at 39.8 (SD = 4.3) months. RESULTS: Toddlers with ASD looked less than TD toddlers at face and mouth regions only when the actress was speaking (direct gaze absence with speech, DG-SP+: d = 0.99, p < .001 for face, d = 0.98, p < .001 for mouth regions; direct gaze present with speech, DG+SP+, d = 1.47, p < .001 for face, d = 1.01, p < .001 for mouth regions). Toddlers with ASD looked less at the eye region only when both gaze and speech cues were present (d = 0.46, p = .03). Salience of the combined DG and SP cues was associated concurrently and prospectively with the severity of autism symptoms, and the association remained significant after controlling for verbal and nonverbal levels. CONCLUSIONS: The study links poor attention to faces with limited salience of audiovisual speech and provides no support for the face avoidance hypothesis in the early stages of ASD. These results are consequential for research on early discriminant and predictive biomarkers as well as identification of novel treatment targets.


Assuntos
Atenção , Transtorno do Espectro Autista/psicologia , Face , Fala , Sinais (Psicologia) , Feminino , Fixação Ocular , Humanos , Lactente , Masculino
5.
Analyst ; 145(11): 3916-3921, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32301943

RESUMO

Biothiols play an important role in living cells and are associated with many diseases. Thus, it is necessary to develop a facile, cost-effective, and convenient analytical method for the detection of biothiols. Nanozymes are functional nanomaterials with enzymatic activities. Due to their unique advantages (e.g., low cost, high stability, and multifunctionality), nanozymes have been extensively used to construct sensing systems. Previous studies demonstrated colorimetric assays for biothiol detection because they could competitively inhibit the peroxidase-like activities of nanozymes. However, few studies were able to differentiate biothiols from each other. To address these challenges, herein, we first synthesized Au alloy nanozymes with better peroxidase-like activities than gold nanoparticles (AuNPs). Then, cross-reactive sensor arrays were constructed with three alloy nanozymes. Six typical biothiols (i.e., glutathione, cysteine, dithiothreitol, mercaptoacetic acid, mercaptoethanol, and mercaptosuccinic acid) were successfully detected and discriminated by the as-prepared nanozyme sensor arrays. Moreover, the practical application of the nanozyme sensor arrays was demonstrated by discriminating biothiols in serum successfully.


Assuntos
Ligas de Ouro/química , Nanopartículas Metálicas/química , Compostos de Sulfidrila/sangue , Animais , Catálise , Bovinos , Colorimetria/métodos , Oxirredução , Compostos de Sulfidrila/química
6.
J Biomech Eng ; 142(12)2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32507897

RESUMO

The purpose of this study was to investigate how sagittal split ramus osteotomy (SSRO) and Le Fort 1 osteotomy affected the stress distribution of the temporomandibular joint (TMJ) during an anterior teeth bite using the three-dimensional (3D) finite element (FE) method. Fourteen orthognathic surgery patients were examined with mandibular prognathism, facial asymmetry, and mandibular retraction. They underwent Le Fort 1 osteotomy in conjunction with SSRO. In addition, ten asymptomatic subjects were recruited as the control group. The 3D models of the mandible, disc, and maxilla were reconstructed according to cone-beam computed tomography (CBCT). Contact was used to simulate the interaction of the disc-condyle, disc-temporal bone, and upper-lower dentition. Muscle forces and boundary conditions corresponding to the anterior occlusions were applied on the models. The stresses on the articular disc and condyle in the pre-operative group were significantly higher than normal. The contact stress and minimum principal stress in TMJ for patients with temporomandibular disorder (TMD) were abnormally higher. The peak stresses of the TMJ of the patients under anterior occlusions decreased after bimaxillary osteotomy. No postoperative TMD symptoms were found. Maxillofacial deformity led to excessive stress on the TMJ. Bimaxillary osteotomy can partially improve the stress distributions of the TMJ and relieve the symptoms of TMD.


Assuntos
Osteotomia Maxilar , Articulação Temporomandibular , Adolescente , Adulto , Humanos , Mandíbula , Adulto Jovem
7.
J Evid Based Dent Pract ; 20(2): 101401, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32473793

RESUMO

OBJECTIVE: To compare the clinical effectiveness of mini-implants (MIs) and conventional anchorage appliances used for orthodontic anchorage reinforcement in patients with class I or II malocclusion with bimaxillary protrusion. MATERIALS AND METHODS: Literature search was conducted through PubMed, Embase, and Cochrane from inception to July 2018. The following Medical Subject Heading terms were used for the search string: "skeletal anchorage", "temporary anchorage devices", "miniscrew implant", "mini-implant", "micro-implant". Standardized mean difference (SMD) and 95% confidence interval (CI) of horizontal and vertical movements of teeth from baseline were used for comparison. RESULTS: A total of 12 studies were included in the final analysis. MI group significantly lowered mesial movement of molars compared to conventional anchorage group (SMD = -1.48, 95% CI = -2.25 to -0.72; P = .0002). There was significantly higher retraction of incisors in the MI group than in the conventional group (SMD = -0.47 mm, 95% CI = -0.87 to -0.07; P = .02). No significant difference was seen in vertical movement of molars (SMD = -0.21 mm, 95% CI = -0.87 to 0.45; P = .52) and incisors (SMD = -0.30, 95% CI = -1.18 to 0.58; P = .5). CONCLUSION: MIs seem to be more effective than the conventional anchorage devices in terms of minimizing unintended mesial movement of molars with maximum retraction of anterior teeth.


Assuntos
Implantes Dentários , Procedimentos de Ancoragem Ortodôntica , Humanos , Dente Molar , Técnicas de Movimentação Dentária
8.
Anal Chem ; 91(23): 15267-15274, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31691556

RESUMO

N-doping strategy has been explored to enhance the activity of carbon nanozymes because the reconstructed electronic structures in N-doped carbon nanozymes are advantageous for the catalytic process. However, carbon nanozymes with high N content are still difficult to obtain due to the instability of N element under high calcination temperatures. To address this challenge, here we proposed a new N-doping strategy to fabricate highly active and specific peroxidase-like carbon nanozymes by using a high N-containing polymer (i.e., polyethylenimine (PEI)) as the N source and a natural clay mineral (i.e., montmorillonite (MMT)) as a template, respectively. We showed that the assembly of MMT with PEI protected N loss under high calcination temperatures and thus retained more catalytically active N sites. The mechanism study showed that the hydroxyl radical could be the key intermediate involved in the peroxidase-like catalysis. We then used the optimized carbon nanozyme with high and specific peroxidase-like activity (i.e., CP600-6) to detect H2O2, glucose, and ascorbic acid. Moreover, we successfully determined the total antioxidant capacity (TAC) in real samples including four commercial beverages, fresh orange juice, and three kinds of vitamin C tablets. The current study not only provides a new strategy for fabricating peroxidase-like nanozymes but also develops a facile TAC assay for future use in evaluation of antioxidant food quality and oxidative stress in healthcare.


Assuntos
Antioxidantes/análise , Carbono/química , Nanoestruturas/química , Ácido Acético/análise , Bentonita/química , Catálise , Glucose/análise , Peróxido de Hidrogênio/análise , Cinética , Polietilenoimina/química
9.
J Evid Based Dent Pract ; 19(4): 101310, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31843178

RESUMO

OBJECTIVE: This meta-analysis aimed at comparing the angular and linear changes of soft tissue profile using conventional anchorage techniques and mini-implant (MI)-based space closure in patients with dentoalveolar protrusion. MATERIALS AND METHODS: Electronic databases, viz. PubMed, Embase, and Cochrane Central Register of Controlled Trials, were searched for relevant literature from their inception to December 2017 according to the specific inclusion and exclusion criteria. The following Medical Subject Heading terms were used for searching: "skeletal anchorage", "temporary anchorage devices", "miniscrew implant", "mini-implant", "micro-implant". Selected randomized control trials (RCTs) were assessed for their quality using Cochrane's Risk of Bias Tool, whereas the Newcastle-Ottawa scale was used for non-RCTs. Standardized mean difference (SMD) and 95% confidence interval (CI) were obtained with either fixed- or random-effects models based on the heterogeneity of the included studies. RESULTS: A total of 5 articles (2 RCTs with moderate risk of bias and 3 high-quality non-RCT studies) were included in the final analysis. The nasolabial angle had significantly greater changes in the MI group than in the conventional anchorage group (SMD = 0.68, 95% CI = 0.39 to 0.97, P < .0001). Significantly higher retraction of the upper lip was seen in the MI group than in the conventional group (SMD = -0.51, 95% CI = -0.84 to -0.18; P = .002). No significant difference was seen in the facial convexity (SMD = -0.34, 95% CI = -0.76 to 0.07, P = .106) and lower lip retraction (SMD = 0.28, 95% CI = -1.72 to 2.28, P = .784) between the groups. CONCLUSION: It was seen that MIs facilitated favorable soft tissue profile than the conventional anchorage devices. However, more high-quality studies are warranted to confirm the clinical effectiveness of MIs.


Assuntos
Procedimentos de Ancoragem Ortodôntica , Humanos , Técnicas de Movimentação Dentária
10.
Proc Natl Acad Sci U S A ; 112(45): 13880-5, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26438850

RESUMO

Oligomerization plays a critical role in shaping the light-harvesting properties of many photosynthetic pigment-protein complexes, but a detailed understanding of this process at the level of individual pigments is still lacking. To study the effects of oligomerization, we designed a single-molecule approach to probe the photophysical properties of individual pigment sites as a function of protein assembly state. Our method, based on the principles of anti-Brownian electrokinetic trapping of single fluorescent proteins, step-wise photobleaching, and multiparameter spectroscopy, allows pigment-specific spectroscopic information on single multipigment antennae to be recorded in a nonperturbative aqueous environment with unprecedented detail. We focus on the monomer-to-trimer transformation of allophycocyanin (APC), an important antenna protein in cyanobacteria. Our data reveal that the two chemically identical pigments in APC have different roles. One (α) is the functional pigment that red-shifts its spectral properties upon trimer formation, whereas the other (ß) is a "protective" pigment that persistently quenches the excited state of α in the prefunctional, monomer state of the protein. These results show how subtleties in pigment organization give rise to functionally important aspects of energy transfer and photoprotection in antenna complexes. The method developed here should find immediate application in understanding the emergent properties of other natural and artificial light-harvesting systems.


Assuntos
Fotossíntese , Pigmentos Biológicos/química , Biopolímeros/química , Soluções , Espectrometria de Fluorescência
11.
Biomacromolecules ; 18(4): 1333-1341, 2017 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-28323418

RESUMO

Oxidative side reaction is one of the major factors hindering the development of hemoglobin-based oxygen carriers (HBOCs). To avoid the oxidative toxicity, we designed and synthesized polydopamine-coated hemoglobin (Hb-PDA) nanoparticles via simple one-step assemblage without any toxic reagent. Hb-PDA nanoparticles showed oxidative protection of Hb by inhibiting the generation of methemoglobin (MetHb) and ferryl (Fe IV) Hb, as well as excellent antioxidant properties by scavenging free radicals and reactive oxygen species (ROS). Interestingly, the scavenging rate of Hb-PDA nanoparticles for ABTS+ radical is at most 89%, while for DPPH radical it reaches 49%. In addition, Hb-PDA efficiently reduced the intracellular H2O2-induced ROS generation. Moreover, Hb-PDA nanoparticles exhibited high oxygen affinity, low effect on blood constituents, and low cytotoxicity. The results indicate that polydopamine-coated hemoglobin might be a promising approach for constructing novel oxygen carriers with the capacity to reduce oxidative side reaction.


Assuntos
Antioxidantes/farmacologia , Materiais Biocompatíveis/farmacologia , Substitutos Sanguíneos , Hemoglobinas/farmacologia , Indóis/farmacologia , Oxigênio/química , Polímeros/farmacologia , Animais , Antioxidantes/administração & dosagem , Antioxidantes/efeitos adversos , Antioxidantes/química , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/efeitos adversos , Materiais Biocompatíveis/química , Compostos de Bifenilo/química , Bovinos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Reagentes de Ligações Cruzadas/química , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Hemoglobinas/administração & dosagem , Hemoglobinas/efeitos adversos , Hemoglobinas/química , Hemólise/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana , Indóis/administração & dosagem , Indóis/efeitos adversos , Indóis/química , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Nanopartículas/química , Picratos/química , Agregação Plaquetária/efeitos dos fármacos , Polímeros/administração & dosagem , Polímeros/efeitos adversos , Polímeros/química , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier
12.
Sci Total Environ ; 917: 170541, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38290684

RESUMO

Microplastics (MPs) can co-occur widely with heavy metals in soil. This study intended to investigate the influences of the co-exposure of polyethylene MPs (0.5 %, w/w) and cadmium (Cd) in black soil on the Cd distribution, enzyme activities, and bacterial communities in both bulk soil and different sized soil aggregates (> 1, 0.50-1, 0.25-0.50, and < 0.25 mm aggregates) after a 90-day incubation. Our results showed that the existence of MPs increased the distributions of Cd in >1 mm and < 0.25 mm soil aggregates and decreased its distributions in 0.50-1 mm and 0.25-0.50 mm soil aggregates. About 12.15 %-17.65 % and 9.03 %-11.13 % of Cd were distributed in the exchangeable and oxidizable forms in bulk soil and various sized soil aggregates after the addition of MPs which were higher than those in the only Cd-treated soil (11.17 %-14.72 % and 8.66 %-10.43 %, respectively), while opposite tendency was found for Cd in the reducible form. Urease and ß-glucosidase activities in the Cd-treated soils were 1.14-1.18 and 1.07-1.31 times higher than those in the Cd-MPs treated soils. MPs disturbed soil bacterial community at phylum level and increased the bacteria richness in bulk soil. The levels of predicted functional genes which are linked to the biodegradation and metabolism of exogenous substances and soil C and N cycles were altered by the co-exposure of Cd and MPs. The findings of this study could help deepen our knowledge about the responses of soil properties, especially microbial community, to the co-occurrence of MPs and heavy metals in soil.


Assuntos
Metais Pesados , Poluentes do Solo , Microplásticos , Cádmio/análise , Plásticos , Solo , Polipropilenos , Poluentes do Solo/análise , Bactérias
13.
ACS Sens ; 9(6): 3282-3289, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38864828

RESUMO

A new type of carbonized polymer dot was prepared by the one-step hydrothermal method of triethoxylsilane (TEOS) and citric acid (CA). The sensor made from carbonized polymer dots (CPDs) showed superior gas sensing performance toward ammonia at room temperature. The Si, O-codoped CPDs exhibited superior ammonia sensing performance at room temperature, including a low practical limit of detection (pLOD) of 1 ppm (Ra/Rg: 1.10, 1 ppm), short response/recovery time (30/36 s, 1 ppm), high humidity resistance (less than 5% undulation when changing relative humidity to 80 from 30%), high stability (less than 5% initial response undulation after 120 days), reliable repeatability, and high selectivity against other interferential gases. The gas sensing mechanism was investigated through control experiments and in situ FTIR, indicating that Si, O-codoping essentially improves the electron transfer capability of CPDs and synergistically dominates the superior ammonia sensing properties of the CPDs. This work presents a facile strategy for constructing novel high-performance, single-component carbonized polymer dots for gas sensing.


Assuntos
Amônia , Polímeros , Temperatura , Amônia/análise , Polímeros/química , Carbono/química , Gases/análise , Gases/química , Silício/química , Limite de Detecção , Pontos Quânticos/química , Oxigênio/química
14.
J Neurol ; 271(5): 2560-2572, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38289536

RESUMO

OBJECTIVES: To investigate the facial scan patterns during emotion recognition (ER) through the dynamic facial expression task and the awareness of social interference test (TASIT) using eye tracking (ET) technology, and to find some ET indicators that can accurately depict the ER process, which is a beneficial supplement to existing ER assessment tools. METHOD: Ninety-six patients with TLE and 88 healthy controls (HCs) were recruited. All participants watched the dynamic facial expression task and TASIT including a synchronized eye movement recording and recognized the emotion (anger, disgust, happiness, or sadness). The accuracy of ER was recorded. The first fixation time, first fixation duration, dwell time, and fixation count were selected and analyzed. RESULTS: TLE patients exhibited ER impairment especially for disgust (Z = - 3.391; p = 0.001) and sadness (Z = - 3.145; p = 0.002). TLE patients fixated less on the face, as evidenced by the reduced fixation count (Z = - 2.549; p = 0.011) of the face and a significant decrease in the fixation count rate (Z = - 1.993; p = 0.046). During the dynamic facial expression task, TLE patients focused less on the eyes, as evidenced by the decreased first fixation duration (Z = - 4.322; p = 0.000), dwell time (Z = - 4.083; p = 0.000), and fixation count (Z = - 3.699; p = 0.000) of the eyes. CONCLUSION: TLE patients had ER impairment, especially regarding negative emotions, which may be attributable to their reduced fixation on the eyes during ER, and the increased fixation on the mouth could be a compensatory effect to improve ER performance. Eye-tracking technology could provide the process indicators of ER, and is a valuable supplement to traditional ER assessment tasks.


Assuntos
Emoções , Epilepsia do Lobo Temporal , Tecnologia de Rastreamento Ocular , Expressão Facial , Fixação Ocular , Humanos , Masculino , Feminino , Adulto , Fixação Ocular/fisiologia , Emoções/fisiologia , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/psicologia , Pessoa de Meia-Idade , Reconhecimento Facial/fisiologia , Adulto Jovem
15.
Bioresour Technol ; 387: 129556, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37517712

RESUMO

This study aimed to investigate the effects of biochar derived from different sources (wheat straw, sawdust and pig manure) on greenhouse gas and microplastics (MPs) mitigation during sewage sludge composting. Compared to the control, all biochar significantly reduced the N2O by 28.91-41.23%, while having no apparent effect on CH4. Sawdust biochar and pig manure biochar significantly reduced the NH3 by 12.53-23.53%. Adding biochar decreased the global warming potential during composting, especially pig manure biochar (177.48 g/kg CO2-eq.). The concentration of MPs significantly increased in the control (43736.86 particles/kg) compared to the initial mixtures, while the addition of biochar promoted the oxidation and degradation of MPs (15896.06-23225.11 particles/kg), with sawdust biochar and manure biochar were more effective. Additionally, biochar significantly reduced the abundance of small-sized (10-100 µm) MPs compared to the control. Moreover, biochar might regulate specific microbes (e.g., Thermobifida, Bacillus and Ureibacillus) to mitigate greenhouse gas emissions and MPs degradation.


Assuntos
Compostagem , Gases de Efeito Estufa , Animais , Suínos , Gases de Efeito Estufa/análise , Esgotos , Microplásticos , Plásticos , Esterco , Solo , Carvão Vegetal/metabolismo , Metano/análise , Nitrogênio/análise
16.
Water Res ; 233: 119786, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36848850

RESUMO

Despite numerous studies that have been devoted to investigating the aging behaviors of microplastics (MPs), dissolved organic carbon (DOC) and nano-plastics (NPs) released from MPs under different aging conditions were limited. Herein, the characterizations and underlying mechanisms of DOC and NPs leaching from MPs (PVC and PS) in the aquatic environment for 130 days under different aging conditions were investigated. The results showed that aging could reduce the abundance of MPs, and high temperature and UV aging generated small-sized MPs (< 100 µm), especially UV aging. DOC-releasing characteristics were related to MP type and aging condition. Meanwhile, MPs were prone to release protein-like and hydrophilic substances except for 60 °C aging of PS MPs. Additionally, 8.77 × 109-8.87 × 1010 and 4.06 × 109-3.94 × 1010 NPs/L were detected in leachates from PVC and PS MPs-aged treatments, respectively. High temperature and UV promoted the release of NPs, especially UV irradiation. Meanwhile, smaller sizes and rougher NPs were observed in UV-aged treatments, implying higher ecological risks of leachates from MPs under UV aging. This study highlights the leachate released from MPs under different aging conditions comprehensively, which could offset the knowledge gap between the MPs' aging and their potential threats.


Assuntos
Matéria Orgânica Dissolvida , Poluentes Químicos da Água , Microplásticos , Plásticos
17.
J Hazard Mater ; 445: 130596, 2023 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-37055952

RESUMO

Microplastics (MPs), as an emerging pollutant, have been widely detected in aquatic, terrestrial, and atmospheric ecosystems. Recently, more researchers indicated that solid organic waste is also a crucial repository of MPs and has become a vital pollution source in ecosystems. Although the occurrence and fate of MPs in solid organic waste and the interaction between MPs and biological treatments have been explored, there still needs to be comprehensive summaries. Hence, this study reviewed the occurrence and characteristics of MPs in solid organic waste and organic fertilizers. Meanwhile, this study summarized the influence of MPs on biological treatments (composting and anaerobic digestion) and their degradation characteristics. MPs are abundant in solid organic waste (0-220 ×103 particles/kg) and organic fertilizer (0-30 ×103 particles/kg), PP and PE are the prominent MPs, and fibers and fragments are the main shapes. MPs can affect the carbon and nitrogen conversion during biological treatments and interfere with microbial communities. The MP's characteristics changed after biological treatments, which should further consider their potential ecological risks. This review points out the existing problems of MPs in organic waste recycling and provides directions for their treatment in the future.


Assuntos
Produtos Biológicos , Microbiota , Poluentes Químicos da Água , Microplásticos/toxicidade , Plásticos , Ecossistema , Carbono , Resíduos Sólidos
18.
Carbohydr Polym ; 300: 120301, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36372499

RESUMO

A major challenge to large-scale production and utilization of bacterial cellulose (BC) for various applications is its low yield and productivity by bacterial cells and the high cost of feedstock. A supplementation of the classical expensive Hestrin and Schramm (HS) medium with 1 % polyethylene terephthalate ammonia hydrolysate (PETAH) resulted in 215 % high yield. Although the physicochemical properties of BC were not significantly influenced, the BC produced in 1 % PETAH-supplemented HS medium showed a higher surface area, which showed 1.39 times higher adsorption capacity for tetracycline than BC produced in HS medium. The 1 % PETAH-supplemented HS medium respectively enhanced the activity of α-UDP-glucose pyrophosphorylase and α-phosphoglucomutase by 30.63 % and 135.24 % and decreased the activity of pyruvate kinase and phosphofructokinase by 40.34 % and 52.63 %. The results of this study provide insights into the activation mechanism of Taonella mepensis by PETAH supplementation for high yield and productivity of BC.


Assuntos
Gluconacetobacter xylinus , Celulose/química , Polietilenotereftalatos , Meios de Cultura/química
19.
Sci Adv ; 9(15): eadf1043, 2023 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-37043582

RESUMO

Switchable and minimally invasive tissue adhesives have great potential for medical applications. However, on-demand adherence to and detachment from tissue surfaces remain difficult. We fabricated a switchable hydrogel film adhesive by designing pattern-tunable wrinkles to control adhesion. When adhered to a substrate, the compressive stress generated from the bilayer system leads to self-similar wrinkling patterns at short and long wavelengths, regulating the interfacial adhesion. To verify the concept and explore its application, we established a random skin flap model, which is a crucial strategy for repairing severe or large-scale wounds. Our hydrogel adhesive provides sufficient adhesion for tissue sealing and promotes neovascularization at the first stage, and then gradually detaches from the tissue while a dynamic wrinkling pattern transition happens. The gel film can be progressively ejected out from the side margins after host-guest integration. Our findings provide insights into tunable bioadhesion by manipulating the wrinkling pattern transition.


Assuntos
Adesivos , Adesivos Teciduais , Pressão , Hidrogéis
20.
ACS Appl Mater Interfaces ; 15(48): 56314-56327, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37983087

RESUMO

Photothermal therapy (PTT) using near-infrared (NIR) conjugated polymers as photosensitizers has exhibited enormous potential for tumor treatment. However, most NIR conjugated polymers have poor therapeutic efficacy due to their faint absorbance in the NIR region and low photothermal conversion efficiency (PCE). Herein, a valuable strategy for designing NIR polymeric photosensitizer PEKBs with an enhanced PCE accompanied by strong NIR absorbance is proposed by means of inserting TPA-AQ as a thermally activated delayed fluorescence unit into a polymeric backbone. In these PEKBs, PEKB-244 with the appropriate molar content of the TPA-AQ unit displays the strongest NIR absorbance and the highest PCE of 64.5%. Theoretical calculation results demonstrate that the TPA-AQ unit in the polymeric backbone can modulate the intramolecular charge transfer effects and the excited energy decay routes for generating higher heat. The prepared nanoparticles (PEKB-244 NPs) exhibit remarkable photothermal conversion capacities and great biocompatibility in aqueous solutions. Moreover, PEKB-244 NPs also show outstanding photothermal stability, displaying negligible changes in the absorbance within 808 nm irradiation of 1 h (800 mW cm-2). Both in vitro and in vivo experimental results further indicate that PEKB-244 NPs can substantially kill cancer cells under NIR laser irradiation. We anticipate that this novel molecular design strategy can be employed to develop excellent NIR photosensitizers for cancer photothermal therapy.


Assuntos
Nanopartículas , Terapia Fototérmica , Fármacos Fotossensibilizantes , Polímeros/farmacologia , Fluorescência , Fototerapia
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