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1.
Plant J ; 113(3): 626-642, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36546867

RESUMEN

Stone cells are the brachysclereid cells in pear (Pyrus) fruit, consisting almost entirely of lignified secondary cell walls. They are distributed mainly near the fruit core and spread radially in the whole fruit. However, the development of stone cells has not been comprehensively characterized, and little is known about the regulation of stone cell formation at the transcriptomic, proteomic, and metabolomic levels. In the present study, we performed phenomic analysis on the stone cells and their associated vascular bundles distributed near the fruit cores. Transcriptomic, proteomic, and metabolomic analyses revealed a significant positive regulation of biological processes which contribute to the lignification and lignin deposition in stone cells near the fruit core, including sucrose metabolism and phenylalanine, tyrosine, tryptophan, and phenylalanine biosynthesis. We found many metabolites generated from the phenylpropanoid pathway contributing to the cell wall formation of stone cells near the fruit core. Furthermore, we identified a key transcription factor, PbbZIP48, which was highly expressed near the fruit core and was shown to regulate lignin biosynthesis in stone cells. In conclusion, the present study provides insight into the mechanism of lignified stone cell formation near the pear fruit core at multiple levels.


Asunto(s)
Frutas , Pyrus , Frutas/metabolismo , Pyrus/metabolismo , Lignina/metabolismo , Proteómica , Multiómica , Regulación de la Expresión Génica de las Plantas
2.
Environ Res ; 249: 118468, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38354881

RESUMEN

Microorganisms have the potential to be applied for the degradation or depolymerization of polyurethane (PU) and other plastic waste, which have attracted global attention. The appropriate strain or enzyme that can effectively degrade PU is the key to treat PU plastic wastes by biological methods. Here, a polyester PU-degrading bacterium Bacillus sp. YXP1 was isolated and identified from a plastic landfill. Three PU substrates with increasing structure complexities, including Impranil DLN, poly (1,4-butylene adipate)-based PU (PBA-PU), and polyester PU foam, were used to evaluate the degradation capacity of Bacillus sp. YXP1. Under optimal conditions, strain YXP1 could completely degrade 0.5% Impranil DLN within 7 days. After 30 days, the weight loss of polyester PU foam by strain YXP1 was as high as 42.1%. In addition, PBA-PU was applied for degradation pathway analysis due to its clear composition and chemical structure. Five degradation intermediates of PBA-PU were identified, including 4,4'-methylenedianiline (MDA), 1,4-butanediol, adipic acid, and two MDA derivates, indicating that strain YXP1 could depolymerize PBA-PU by the hydrolysis of ester and urethane bonds. Furthermore, the extracellular enzymes produced by strain YXP1 could hydrolyze PBA-PU to generate MDA. Together, this study provides a potential bacterium for the biological treatment of PU plastic wastes and for the mining of functional enzymes.


Asunto(s)
Bacillus , Biodegradación Ambiental , Poliuretanos , Poliuretanos/química , Bacillus/metabolismo , Bacillus/aislamiento & purificación , Bacillus/genética , Poliésteres/metabolismo
3.
Proc Natl Acad Sci U S A ; 118(11)2021 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-33729990

RESUMEN

Cellulose is synthesized by cellulose synthases (CESAs) from the glycosyltransferase GT-2 family. In plants, the CESAs form a six-lobed rosette-shaped CESA complex (CSC). Here we report crystal structures of the catalytic domain of Arabidopsis thaliana CESA3 (AtCESA3CatD) in both apo and uridine diphosphate (UDP)-glucose (UDP-Glc)-bound forms. AtCESA3CatD has an overall GT-A fold core domain sandwiched between a plant-conserved region (P-CR) and a class-specific region (C-SR). By superimposing the structure of AtCESA3CatD onto the bacterial cellulose synthase BcsA, we found that the coordination of the UDP-Glc differs, indicating different substrate coordination during cellulose synthesis in plants and bacteria. Moreover, structural analyses revealed that AtCESA3CatD can form a homodimer mainly via interactions between specific beta strands. We confirmed the importance of specific amino acids on these strands for homodimerization through yeast and in planta assays using point-mutated full-length AtCESA3. Our work provides molecular insights into how the substrate UDP-Glc is coordinated in the CESAs and how the CESAs might dimerize to eventually assemble into CSCs in plants.


Asunto(s)
Proteínas de Arabidopsis/química , Arabidopsis/química , Celulosa/metabolismo , Glucosiltransferasas/química , Uridina Difosfato Glucosa/química , Aminoácidos , Arabidopsis/enzimología , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Dominio Catalítico , Cristalografía por Rayos X , Glucosiltransferasas/genética , Glucosiltransferasas/metabolismo , Manganeso/química , Manganeso/metabolismo , Mutación , Multimerización de Proteína , Uridina Difosfato Glucosa/metabolismo
4.
Int J Mol Sci ; 24(22)2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-38003625

RESUMEN

Due to the extensive utilization of poly (ethylene terephthalate) (PET), a significant amount of PET waste has been discharged into the environment, endangering both human health and the ecology. As an eco-friendly approach to PET waste treatment, biodegradation is dependent on efficient strains and enzymes. In this study, a screening method was first established using polycaprolactone (PCL) and PET nanoparticles as substrates. A PET-degrading strain YX8 was isolated from the surface of PET waste. Based on the phylogenetic analysis of 16S rRNA and gyrA genes, this strain was identified as Bacillus safensis. Strain YX8 demonstrated the capability to degrade PET nanoparticles, resulting in the production of terephthalic acid (TPA), mono (2-hydroxyethyl) terephthalic acid (MHET), and bis (2-hydroxyethyl) terephthalic acid (BHET). Erosion spots on the PET film were observed after incubation with strain YX8. Furthermore, the extracellular enzymes produced by strain YX8 exhibited the ability to form a clear zone on the PCL plate and to hydrolyze PET nanoparticles to generate TPA, MHET, and BHET. This work developed a method for the isolation of PET-degrading microorganisms and provides new strain resources for PET degradation and for the mining of functional enzymes.


Asunto(s)
Etilenos , Tereftalatos Polietilenos , Humanos , Tereftalatos Polietilenos/química , Filogenia , ARN Ribosómico 16S/genética , Biodegradación Ambiental
5.
BMC Oral Health ; 23(1): 701, 2023 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-37773120

RESUMEN

BACKGROUND: Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) represent an effective and promising strategy for periodontitis, although studies remain pre-clinical. Herein, a meta-analysis was conducted to assess the efficacy of MSC-EVs in animal models of periodontitis. METHODS: The PubMed, Web of Science, and Embase electronic databases were searched up to Dec 2022 to retrieve preclinical studies examining the use of MSC-EVs for periodontitis treatment. Meta-analyses and sub-group analyses were performed to assess the effect of MSC-EVs on Bone Volume/Total Volume (BV/TV) or the distance between the cementoenamel junction and alveolar bone crest (CEJ-ABC) in pre-clinical animal models of periodontitis. RESULTS: 11 studies published from Mar 2019 to Oct 2022 met the inclusion criteria. Overall, MSC-EVs contributed to periodontal bone regeneration in the inflammatory bone loss area due to periodontitis, as represented by a weighted mean difference (WMD) of 14.07% (95% CI = 6.73, 21.41%, p < 0.001) for BV/TV and a WMD of -0.12 mm (95% CI= -0.14, -0.11 mm, p < 0.001) for CEJ-ABC. However, sub-analysis suggested that there was no significant difference in CEJ-ABC between studies with bioactive scaffolds and studies without bioactive scaffolds (p = 0.60). CONCLUSIONS: The present study suggests that MSC-EVs may represent an attractive therapy for the treatment of inflammatory bone loss within periodontitis.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , Periodontitis , Animales , Regeneración Ósea , Modelos Animales de Enfermedad , Periodontitis/terapia
6.
Arch Microbiol ; 204(7): 378, 2022 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35678928

RESUMEN

During an investigation of freshwater fungi in Jiangxi province, China, a new hyphomycetous fungus, Aquapteridospora jiangxiensis, was collected and isolated. Aquapteridospora jiangxiensis is characterized by its unbranched and guttulate conidiophores with multi-septa swollen at the base, polyblastic conidiogenous cells with sympodial proliferations, and denticles, and guttulate conidia with a sheath. A photo plate of the macro- and micro-morphology and a muti-loci (ITS, LSU, SSU, TEF1 and RPB2) phylogenetic tree are provided. A key to the species of Aquapteridospora is also presented in this paper.


Asunto(s)
Ascomicetos , Hongos Mitospóricos , ADN de Hongos/genética , ADN Ribosómico , Ecosistema , Agua Dulce , Filogenia , Análisis de Secuencia de ADN
7.
Environ Res ; 206: 112618, 2022 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-34954145

RESUMEN

Well dispersed nanocatalysts on porous substrate with macroscopic morphology are highly desired for the application of heterogeneous catalysis. Traditional fabrication process suffers from multiple steps for controlling the structure on nanocatalysts and matrix or both. Herein, we report a facile strategy for the synthesis of millimeter-sized hierarchical porous carbon beads (HPCBs) which containing well dispersed hollow-nano carbon boxes for peroxymonosulfate catalysis. Specially, the precursors of HPCBs were prepared by phase inversion method, which involving introduction of zeolitic imidazolate framework (ZIF-8) nanocubes into polyacrylonitrile (PAN) solutions followed by solidification of the mixture. After pyrolysis, nitrogen doped and hierarchical porous HPCBs with diameter of about 1.2 mm were obtained. The merits of our synthesis strategy lie in that synchronizes the hollow microstructure evolution with the shaping of ZIF-8 nanocubes into millimeter scale beads. Attribute to its special structure feature and the appropriate chemical composition, the resultant millimeter-sized HPCBs exhibit enhanced catalytic performance by activation of peroxymonosulfate (PMS) for tetracycline degradation. The degradation efficiency of TC is up to 85.1% within 120 min, which is 18% higher than that of ZIF8-Solid/PAN carbon bead (SPCBs). In addition, the possible decomposition pathways, main reactive oxygen species, and reasonable enhanced mechanism for the HPCBs/PMS system are systematically investigated by quenching experiments, electron paramagnetic resonance (EPR) and liquid chromatography-mass spectrometry (LC-MS). This work addresses the issue of easy aggregation and recycling of carbon materials in industrial productions and extends the prospects of carbon materials in engineering applications.


Asunto(s)
Carbono , Zeolitas , Resinas Acrílicas , Carbono/química , Catálisis , Peróxidos , Porosidad
8.
Mol Pharm ; 18(8): 2935-2946, 2021 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-34191525

RESUMEN

The adoptive transfer of natural killer (NK) cells, which can recognize and obliterate cancer cells, provides a practical alternative to current treatment modalities to improve cancer patients' survival. However, translating NK cell therapies to treat solid tumors has proven challenging due to the tumor microenvironment (TME). Hypoxia in the TME induces immunosuppression that inhibits the cytotoxic function of NK cells. Thus, reversing hypoxia-induced immunosuppression is critical for effective adoptive NK cell immunotherapy. In this study, we use manganese dioxide nanoparticles (MnO2 NPs) to catalyze the degradation of tumor-produced hydrogen peroxide, thereby generating oxygen. For improved biocompatibility and modulation of oxygen production, the MnO2 NPs were encapsulated into poly(lactic-co-glycolic) to produce particles that are 116 nm in size and with a ζ-potential of +17 mV (PLGA-MnO2 NPs). The PLGA-MnO2 NPs showed first-order oxygen production and sustained high oxygen tension compared to equivalent amounts of bare MnO2 NPs in the presence of H2O2. The PLGA-MnO2 NPs were biocompatible, reduced hypoxia after penetration into the core of cancer spheroids, and decreased hypoxia-induced factor 1 α expression. Reducing hypoxia in the spheroid resulted in a decrease in the potent immunosuppressors, adenosine, and lactate, which was confirmed by electrospray ionization mass spectroscopy (ESI-MS). ESI-MS also showed a change in the metabolism of the amino acids aspartate, glutamine, and glutamate after hypoxia reduction in the cancer cells. Notably, the spheroids' microenvironment changes enhanced NK cells' cytotoxicity, which obliterated the spheroids. These results demonstrate that reducing hypoxia-induced immunosuppression in tumors is a potent strategy to increase the potency of cytotoxic immune cells in the TME. The developed NPs are promising new tools to improve adoptive NK cell therapy.


Asunto(s)
Inmunidad Adaptativa/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Hipoxia de la Célula/efectos de los fármacos , Células Asesinas Naturales/inmunología , Compuestos de Manganeso/farmacología , Nanopartículas del Metal/química , Nanocápsulas/química , Óxidos/farmacología , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Esferoides Celulares/inmunología , Adenosina/metabolismo , Traslado Adoptivo/métodos , Neoplasias de la Mama/patología , Hipoxia de la Célula/inmunología , Femenino , Humanos , Peróxido de Hidrógeno/metabolismo , Tolerancia Inmunológica/efectos de los fármacos , Ácido Láctico/metabolismo , Células MCF-7 , Compuestos de Manganeso/química , Óxidos/química , Tamaño de la Partícula , Transducción de Señal/efectos de los fármacos , Transducción de Señal/inmunología , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología
9.
BMC Musculoskelet Disord ; 22(1): 805, 2021 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-34537042

RESUMEN

BACKGROUND: The impact of intravertebral cleft (IVC) on cement leakage in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCFs) has been discussed. However, the results were conflicting, as the study population and cement leakage classification were heterogeneous. The aim of the study was to evaluate the impact of IVC on the incidence of leakage through vein, leakage through cortex as well as general leakage in PVP for OVCFs. METHODS: All patients with OVCFs who underwent PVP between January 2016 and June 2019 at our institution were retrospectively reviewed. Patients were eligible for this case-control study if they were diagnosed as single level fracture in spine. After inclusive and exclusive criteria were met, a total of 139 patients with IVC were enrolled as the study group. Non-IVC controls were matched in a 1:1 ratio in age (within 3 years), sex and fracture severity with patients in study group. Cement leakage were classified into four types [type B (through basivertebral vein), type S (through segmental vein), type-C (through a cortical defect), and type D (intradiscal leakage)], furtherly into two types [venous type (type-B or/and type S) and cortical type (type-C or/and type-D)]. A general leakage rate and a specific leakage rate per each type were compared between both groups. RESULTS: Each group included 139 patients. Groups were homogenous for age, sex, fracture severity, fracture location, fracture type, cement volume, puncture approach and property of cement. Compared with control group, IVC group had a significantly lower rate of type-B (20.9% vs. 31.7%, P = 0.041), type-S (24.5% vs. 52.5%, P = 0.000), and venous type leakage (37.4% vs. 67.6%, P = 0.000), a significantly higher rate of type-C (25.9% vs. 12.2%, P = 0.004), type-D (16.5% vs. 6.5%, P = 0.009), and cortical type leakage (40.3% vs. 16.5%, P = 0.000), no significant difference on the rate of general leakage (67.6% vs. 76.3%, P = 0.109). CONCLUSION: IVC decreased the risk of cement leakage through vein and increased the risk of cement leakage through cortex. However, it had no significant effect on the occurrence of general leakage.


Asunto(s)
Fracturas por Compresión , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Vertebroplastia , Cementos para Huesos/uso terapéutico , Estudios de Casos y Controles , Preescolar , Fracturas por Compresión/diagnóstico por imagen , Fracturas por Compresión/epidemiología , Fracturas por Compresión/cirugía , Humanos , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/cirugía , Estudios Retrospectivos , Factores de Riesgo , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/cirugía , Resultado del Tratamiento , Vertebroplastia/efectos adversos
10.
J Adv Nurs ; 75(5): 1108-1118, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30507045

RESUMEN

AIM: The primary aim of this study is to compare an oropharyngeal suction intervention versus usual care on microaspiration in intubated patients. Secondary aims are to evaluate the intervention on ventilator-associated condition rates, time to occurrence and compare tracheal-oral α-amylase ratios between groups. DESIGN: Prospective randomized clinical trial. METHODS: The study received funding from the National Institutes of Health in February 2014 and Institutional Review Board approval in July 2013. Over 4 years, a convenience sample of 600 orally intubated, ventilated adult patients will be enrolled within 24 hr of intubation. The target sample is 400 participants randomized to the two groups. The intervention involves enhanced suctioning of the mouth and oropharynx every 4 hr, while the usual care group receives a sham suctioning. The research team will deliver usual oral care to all patients every 4 hr and collect oral and tracheal specimens every 12 hr, to quantify α-amylase levels to detect aspiration of oral secretions. Study completers must be enrolled at least 36 hr (baseline and three paired samples). Outcomes include α-amylase levels, percent of positive specimens, ventilator-associated conditions, length of stay, ventilator hours, and discharge disposition. DISCUSSION: Enrolment has closed, and data analysis has begun. Subgroup analyses emerged, contributing to future research knowledge. IMPACT: Standardized interventions have reduced but do not address all risk factors associated with ventilator-associated conditions. This study provides the potential to reduce microaspiration and associated sequelae in critically ill, intubated patients.


Asunto(s)
Enfermedad Crítica/terapia , Intubación Intratraqueal/efectos adversos , Atención de Enfermería/normas , Neumonía por Aspiración/enfermería , Neumonía por Aspiración/prevención & control , Respiración Artificial/efectos adversos , Succión/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Guías de Práctica Clínica como Asunto , Estudios Prospectivos , Factores de Riesgo , Método Simple Ciego
11.
Water Sci Technol ; 2017(2): 378-389, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29851390

RESUMEN

In this work, we prepared amidoxime-functionalized polyacrylonitrile (APAN) micro/nanofibers by modifying solution-blown PAN fibers with hydroxylamine hydrochloride, and investigated the adsorption performance of the APAN fibers for Cd(II), Cr(III), Cu(II), Ni(II), Pb(II) and Zn(II) from aqueous solutions. Batch experiments and quantitative analysis were conducted considering initial pH and contact time as controlling parameters. The equilibrium data were better explained by the Langmuir model with maximum adsorption capacities of 185, 204, 105, 104, 345 and 91 mg/g for Cd(II), Cr(III), Cu(II), Ni(II), Pb(II) and Zn(II), respectively. The adsorption kinetics were found to follow the pseudo-second-order kinetic model. The calculated thermodynamic parameters demonstrated that the adsorption of metal ions onto APAN fibers is feasible, spontaneous and endothermic. The five adsorption-desorption cycle experiments showed that APAN micro/nanofiber adsorbent exhibits good reusability, and has a potential application for the removal of heavy metals from wastewater.


Asunto(s)
Resinas Acrílicas/análisis , Metales Pesados/química , Nanofibras/análisis , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Adsorción , Cinética , Termodinámica
12.
Appl Microbiol Biotechnol ; 98(20): 8685-95, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25056289

RESUMEN

Dental caries and periodontitis are common bacterial mouth infections. As a potentially attractive substitute for conventional antibiotics, antimicrobial peptides have been widely tested and used for controlling bacterial infections. In this study, we tested the efficacy of the peptides from the skin secretions of Rana chensinensis for killing several major cariogenic and periodontic pathogens as well as Candida albicans. L-K6, a temporin-1CEb analog, exhibited high antimicrobial activity against the tested oral pathogens and was able to inhibit Streptococcus mutans biofilm formation and reduce 1-day-old S. mutans biofilms with a minimum biofilm inhibitory concentration and reducing concentration of 3.13 and 6.25 µM, respectively. The results of confocal laser scanning microscopy demonstrated that the peptide significantly reduced cell viability within oral biofilms. Furthermore, as little as 5 µM L-K6 significantly inhibited lipopolysaccharide (LPS)- and interleukin-1ß-induced productions of interleukin-8 and tumor necrosis factor-α from THP-1 monocytic cells. This anti-inflammatory activity is associated with the binding of L-K6 to LPS and neutralizing LPS-induced proinflammatory responses in THP-1 cells, as well as dissociating LPS aggregates. Our results suggest that L-K6 may have potential clinical applications in treating dental caries by killing S. mutans within dental plaque and acting as anti-inflammatory agents in infected tissues.


Asunto(s)
Antiinflamatorios/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/fisiología , Animales , Antiinflamatorios/aislamiento & purificación , Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Candida albicans/fisiología , Línea Celular , Interleucina-8/antagonistas & inhibidores , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Monocitos/efectos de los fármacos , Ranidae , Streptococcus mutans/crecimiento & desarrollo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
13.
Biomed Mater ; 19(4)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38740053

RESUMEN

This study aimed to investigate the effects of magnesium-doped bioactive glass (Mg-BG) on the mineralization, odontogenesis, and anti-inflammatory abilities of human dental pulp stem cells (hDPSCs). Mg-BG powders with different Mg concentrations were successfully synthesized via the sol-gel method and evaluated using x-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. Apatite formation was observed on the surfaces of the materials after soaking in simulated body fluid. hDPSCs were cultured with Mg-BG powder extracts in vitro, and no evident cytotoxicity was observed. Mg-BG induced alkaline phosphatase (ALP) expression and mineralization of hDPSCs and upregulated the expression of odontogenic genes, including those encoding dentin sialophosphoprotein, dentin matrix protein 1, ALP, osteocalcin, and runt-related transcription factor 2. Moreover, Mg-BG substantially suppressed the secretion of inflammatory cytokines (interleukin [IL]-4, IL-6, IL-8, and tumor necrosis factor-alpha). Collectively, the results of this study suggest that Mg-BG has excellent in vitro bioactivity and is a potential material for vital pulp therapy of inflamed pulps.


Asunto(s)
Antiinflamatorios , Pulpa Dental , Vidrio , Magnesio , Células Madre , Humanos , Pulpa Dental/citología , Pulpa Dental/metabolismo , Magnesio/química , Antiinflamatorios/farmacología , Antiinflamatorios/química , Células Madre/citología , Células Madre/metabolismo , Vidrio/química , Odontogénesis/efectos de los fármacos , Citocinas/metabolismo , Células Cultivadas , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Difracción de Rayos X , Espectroscopía Infrarroja por Transformada de Fourier , Fosfatasa Alcalina/metabolismo , Cerámica/química , Cerámica/farmacología , Ensayo de Materiales , Polvos , Microscopía Electrónica de Rastreo
14.
Chemosphere ; 351: 141185, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38215831

RESUMEN

Chromium-containing wastewater causes serious environmental pollution due to the harmfulness of Cr(VI). The ferrite process is typically used to treat chromium-containing wastewater and recycle the valuable chromium metal. However, the current ferrite process is unable to fully transform Cr(VI) into chromium ferrite under mild reaction conditions. This paper proposes a novel ferrite process to treat chromium-containing wastewater and recover valuable chromium metal. The process combines FeSO4 reduction and hydrothermal treatment to remove Cr(VI) and form chromium ferrite composites. The Cr(VI) concentration in the wastewater was reduced from 1040 mg L-1 to 0.035 mg L-1, and the Cr(VI) leaching toxicity of the precipitate was 0.21 mg L-1 under optimal hydrothermal conditions. The precipitate consisted of micron-sized ferrochromium spinel multiphase with polyhedral structure. The mechanism of Cr(VI) removal involved three steps: 1) partial oxidation of FeSO4 to Fe(III) hydroxide and oxy-hydroxide; 2) reduction of Cr(VI) by FeSO4 to Cr(III) and Fe(III) precipitates; 3) transformation and growth of the precipitates into chromium ferrite composites. This process meets the release standards of industrial wastewater and hazardous waste and can improve the efficiency of the ferrite process for toxic heavy metal removal.


Asunto(s)
Óxido de Aluminio , Aleaciones de Cromo , Óxido de Magnesio , Aguas Residuales , Contaminantes Químicos del Agua , Compuestos Férricos/química , Cromo/química , Hidróxidos , Contaminantes Químicos del Agua/análisis
15.
Head Face Med ; 20(1): 12, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38368383

RESUMEN

BACKGROUND: The surgically facilitated orthodontic strategy has been a promising strategy for orthodontic treatment recently. Therefore, the present meta-analysis was conducted to assess the available scientific evidence regarding the clinical outcomes, including the potential detrimental effects associated with these surgical procedures, with the aim of providing much more evidence-based information for clinical practice. METHODS: An electronic search of three databases (PubMed, Cochrane, and Embase) and a manual search of relevant articles published up to May 2023 were carried out. Clinical trials (≥ 10 subjects) that utilized surgically facilitated orthodontic strategies with clinical and/or radiographic outcomes were included. Meta-analyses and sub-group analyses were performed to analyze the standardized mean difference (SMD) or weighted mean difference (WMD), and confidence interval (CI) for the recorded variables. RESULTS: Nineteen studies published from Oct 2012 to May 2023 met the inclusion criteria. Based on the analysis outcomes, corticotomy treatment significantly decreased the alignment duration (WMD: -1.08 months; 95% CI = -1.65, -0.51 months, P = 0.0002), and accelerated the canine movement (WMD: 0.72 mm; 95% CI = 0.63, 0.81 mm, P < 0.00001) compared to the traditional orthodontic group. The periodontally accelerated osteogenic orthodontic (PAOO) strategy markedly reduced the total treatment duration (SMD: -1.98; 95% CI = -2.59, -1.37, P < 0.00001) and increased the bone thickness (SMD:1.07; 95% CI = 0.74, 1.41, P < 0.00001) compared to traditional orthodontic treatment. CONCLUSION: The present study suggests that facilitated orthodontic treatment in terms of corticotomy and PAOO strategy may represent attractive and effective therapeutic strategy for orthodontic patients.

16.
J Hazard Mater ; 472: 134493, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38696960

RESUMEN

Environmental pollution caused by plastic waste has become global problem that needs to be considered urgently. In the pursuit of a circular plastic economy, biodegradation provides an attractive strategy for managing plastic wastes, whereas effective plastic-degrading microbes and enzymes are required. In this study, we report that Blastobotrys sp. G-9 isolated from discarded plastic in landfills is capable of depolymerizing polyurethanes (PU) and poly (butylene adipate-co-terephthalate) (PBAT). Strain G-9 degrades up to 60% of PU foam after 21 days of incubation at 28 â„ƒ by breaking down carbonyl groups via secretory hydrolase as confirmed by structural characterization of plastics and degradation products identification. Within the supernatant of strain G-9, we identify a novel cutinase BaCut1, belonging to the esterase family, that can reproduce the same effect. BaCut1 demonstrates efficient degradation toward commercial polyester plastics PU foam (0.5 mg enzyme/25 mg plastic) and agricultural film PBAT (0.5 mg enzyme/10 mg plastic) with 50% and 18% weight loss at 37 â„ƒ for 48 h, respectively. BaCut1 hydrolyzes PU into adipic acid as a major end-product with 42.9% recovery via ester bond cleavage, and visible biodegradation is also identified from PBAT, which is a beneficial feature for future recycling economy. Molecular docking, along with products distribution, elucidates a special substrate-binding modes of BaCut1 with plastic substrate analogue. BaCut1-mediated polyester plastic degradation offers an alternative approach for managing PU plastic wastes through possible bio-recycling.


Asunto(s)
Biodegradación Ambiental , Hidrolasas de Éster Carboxílico , Poliuretanos , Reciclaje , Poliuretanos/química , Hidrolasas de Éster Carboxílico/metabolismo , Hidrolasas de Éster Carboxílico/química , Burkholderiales/enzimología , Burkholderiales/metabolismo , Ácidos Ftálicos/metabolismo , Ácidos Ftálicos/química , Plásticos/química , Plásticos/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Poliésteres
17.
Jpn Dent Sci Rev ; 59: 181-190, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37388714

RESUMEN

Biomineralization is a highly regulated process that results in the deposition of minerals in a precise manner, ultimately producing skeletal and dental hard tissues. Recent studies have highlighted the crucial role played by intracellular processes in initiating biomineralization. These processes involve various organelles, such as the endoplasmic reticulum(ER), mitochondria, and lysosomes, in the formation, accumulation, maturation, and secretion of calcium phosphate (CaP) particles. Particularly, the recent in-depth study of the dynamic process of the formation of amorphous calcium phosphate(ACP) precursors among organelles has made great progress in the development of the integrity of the biomineralization chain. However, the precise mechanisms underlying these intracellular processes remain unclear, and they cannot be fully integrated with the extracellular mineralization mechanism and the physicochemical structure development of the mineralization particles. In this review, we aim to focus on the recent progress made in understanding intracellular mineralization organelles' processes and their relationship with the physicochemical structure development of CaP and extracellular deposition of CaP particles.

18.
J Plast Reconstr Aesthet Surg ; 77: 219-227, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36587477

RESUMEN

BACKGROUND: Polyacrylamide hydrogel has been prohibited since 2006 due to numerous complications. Unsatisfactory breast contour was always observed in patients after PAAG removal. The same occurred in patients after silicone prosthesis removal. We attempt to compare and analyze the difference in postoperative breast conditions and pathology between the two groups. METHODS: We retrospectively reviewed the data of patients who underwent PAAG or silicone prosthesis removal between 2011 and 2021. The BREAST-Q was used to evaluate the follow-up results, including satisfaction with breasts, physical well-being, psychosocial well-being, sexual well-being, and the operation. RESULTS: A total of 63 patients were analyzed. The PAAG group complained of more lumps or indurations (p = 0.004), benefited less from operations as for symptomatic relief (p = 0.002), and had more chronic inflammation(p = 0.000) than the silicone group. No breast cancer was found. All the Breast-Q scores were lower in the PAAG group than in the silicone group, and there was a significant difference in satisfaction with physical well-being (p = 0.035). Besides, patients without symptoms tended to score higher in all aspects of Breast-Q than patients with symptoms after removal. The two groups (symptom & no symptom) differed in psychosocial well-being (p = 0.043) and satisfaction with operation (p = 0.048). CONCLUSIONS: The breast contour of patients after PAAG or silicone prosthesis removal was worse than before. Early removal of PAAG before complications arise may result in a better surgical benefit. There is no doubt that PAAG are harmful both physically and psychologically. All patients are suggested to have PAAG injections removed.


Asunto(s)
Implantes de Mama , Remoción de Dispositivos , Mamoplastia , Femenino , Humanos , Embarazo , Implantes de Mama/efectos adversos , Estudios de Seguimiento , Mamoplastia/efectos adversos , Mamoplastia/instrumentación , Mamoplastia/métodos , Prótesis e Implantes , Estudios Retrospectivos , Siliconas
19.
Sheng Wu Gong Cheng Xue Bao ; 39(5): 1976-1986, 2023 May 25.
Artículo en Zh | MEDLINE | ID: mdl-37212225

RESUMEN

Although polyurethane (PUR) plastics play important roles in daily life, its wastes bring serious environmental pollutions. Biological (enzymatic) degradation is considered as an environmentally friendly and low-cost method for PUR waste recycling, in which the efficient PUR-degrading strains or enzymes are crucial. In this work, a polyester PUR-degrading strain YX8-1 was isolated from the surface of PUR waste collected from a landfill. Based on colony morphology and micromorphology observation, phylogenetic analysis of 16S rDNA and gyrA gene, as well as genome sequence comparison, strain YX8-1 was identified as Bacillus altitudinis. The results of high performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) showed that strain YX8-1 was able to depolymerize self-synthesized polyester PUR oligomer (PBA-PU) to produce a monomeric compound 4, 4'-methylene diphenylamine. Furthermore, strain YX8-1 was able to degrade 32% of the commercialized polyester PUR sponges within 30 days. This study thus provides a strain capable of biodegradation of PUR waste, which may facilitate the mining of related degrading enzymes.


Asunto(s)
Poliésteres , Poliuretanos , Poliuretanos/química , Poliésteres/química , Cromatografía Liquida , Filogenia , Espectrometría de Masas en Tándem , Bacterias/metabolismo , Biodegradación Ambiental
20.
Sheng Wu Gong Cheng Xue Bao ; 39(5): 1963-1975, 2023 May 25.
Artículo en Zh | MEDLINE | ID: mdl-37212224

RESUMEN

Polyurethane (PUR) plastics is widely used because of its unique physical and chemical properties. However, unreasonable disposal of the vast amount of used PUR plastics has caused serious environmental pollution. The efficient degradation and utilization of used PUR plastics by means of microorganisms has become one of the current research hotspots, and efficient PUR degrading microbes are the key to the biological treatment of PUR plastics. In this study, an Impranil DLN-degrading bacteria G-11 was isolated from used PUR plastic samples collected from landfill, and its PUR-degrading characteristics were studied. Strain G-11 was identified as Amycolatopsis sp. through 16S rRNA gene sequence alignment. PUR degradation experiment showed that the weight loss rate of the commercial PUR plastics upon treatment of strain G-11 was 4.67%. Scanning electron microscope (SEM) showed that the surface structure of G-11-treated PUR plastics was destroyed with an eroded morphology. Contact angle and thermogravimetry analysis (TGA) showed that the hydrophilicity of PUR plastics increased along with decreased thermal stability upon treatment by strain G-11, which were consistent with the weight loss and morphological observation. These results indicated that strain G-11 isolated from landfill has potential application in biodegradation of waste PUR plastics.


Asunto(s)
Plásticos , Poliuretanos , Plásticos/metabolismo , Poliuretanos/química , ARN Ribosómico 16S , Bacterias/genética , Biodegradación Ambiental
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