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1.
Ecotoxicol Environ Saf ; 283: 116783, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39067076

RESUMEN

Residues of herbicides with the extensive applications may impact the soil ecosystem and ultimately threaten agricultural sustainability. However, the effects of long-term herbicide residues on soil multifunctionality and the soil microbial community remain poorly understood. Here, we evaluated relationships between soil multifunctionality and soil microbial communities with residual herbicide concentrations by surveying and analyzing 62 black soil samples collected from an agricultural area in northeastern China. Total residual herbicide concentrations varied from 35 to 568 µg/kg in the soil samples. The response of soil multifunctionality to increasing residual herbicide concentrations exhibited an inverted U-shaped relationship with a peak at approximately 310 µg/kg, with net mineralized organic nitrogen (Nm) and total nitrogen (TN) exhibiting the same trend. Microbial community richness was significantly lower in soil samples with high residual herbicide concentrations (> 310 µg/kg, HG) compared to low residual herbicide concentrations (< 310 µg/kg, LG). In addition, the relative abundances of specific keystone microbial genera differed significantly between LG and HG: norank_f_Acetobacteraceae, norank_f_Caldilineaceae, Candidatus_Alysiosphaera, and Gonytrichum. The relative abundances of these genera were also significantly correlated with soil multifunctionality. Structural equation models (SEMs) further showed that herbicide residues influenced soil multifunctionality by affecting these specific keystone genera. Our study demonstrates that long-term herbicide residues significantly impact the multifunctionality of agricultural black soil, where low concentrations stimulate while high concentrations inhibit, underscoring the need for reasonable application of herbicides to maintain soil ecosystem health.

2.
J Environ Sci (China) ; 145: 50-63, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38844323

RESUMEN

Herbicides (HBCs) are extensively used in modern agriculture. However, their potential negative impacts on environmental media have emerged as a significant environmental concern. In this study, we employed positive matrix factorization (PMF) to identify the potential sources of HBCs. Furthermore, we utilized a multi-matrix ecological risk model to assess the risks associated with HBCs in both surface water and groundwater in the black soil region of Northeast China. The findings revealed that the levels of ∑15HBCs in surface water and groundwater ranged from 585.84 to 6466.96 ng/L and 4.80 to 11,774.64 ng/L, respectively. The PMF results indicated that surface runoff and erosion accounted for 50% of the total HBCs in water, serving as the primary sources. All tested HBCs exhibited acute risk values within acceptable levels. The risk index for the ∑15HBCs was categorized as "moderate risk" in 31% of the surface waters and 13% of the groundwaters. However, 4% of the groundwater sampling sites reached the "high risk" level. The chronic risk quotient of ∑15HBCs in surface water and groundwater was 92% and 62% at the "high risk" level, respectively. Interestingly, non-carcinogenic HBCs contributed more significantly to the ecotoxicology of the aquatic system than carcinogenic HBCs. This study provides comprehensive information on the legacy of HBCs in water bodies and emphasizes the potential risks posed by HBCs to aquatic systems. The results obtained from this study could help relevant management authorities in developing and implementing effective regulations to mitigate the ecological and environmental risks associated with HBCs.


Asunto(s)
Monitoreo del Ambiente , Agua Subterránea , Herbicidas , Contaminantes Químicos del Agua , China , Medición de Riesgo , Herbicidas/análisis , Herbicidas/toxicidad , Contaminantes Químicos del Agua/análisis , Agua Subterránea/química , Ciudades
3.
Bioresour Technol ; 404: 130918, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38823562

RESUMEN

Symbiosis between Glycine max and Bradyrhizobium diazoefficiens were used as a model system to investigate whether biohydrogen utilization promotes the transformation of the tetrachlorobiphenyl PCB77. Both a H2 uptake-positive (Hup+) strain (wild type) and a Hup- strain (a hupL deletion mutant) were inoculated into soybean nodules. Compared with Hup- nodules, Hup+ nodules increased dechlorination significantly by 61.1 % and reduced the accumulation of PCB77 in nodules by 37.7 % (p < 0.05). After exposure to nickel, an enhancer of uptake hydrogenase, dechlorination increased significantly by 2.2-fold, and the accumulation of PCB77 in nodules decreased by 54.4 % (p < 0.05). Furthermore, the tetrachlorobiphenyl transformation in the soybean root nodules was mainly testified to be mediated by nitrate reductase (encoded by the gene NR) for tetrachlorobiphenyl dechlorination and biphenyl-2,3-diol 1,2-dioxygenase (bphC) for biphenyl degradation. This study demonstrates for the first time that biohydrogen utilization has a beneficial effect on tetrachlorobiphenyl biotransformation in a legume-rhizobium symbiosis.


Asunto(s)
Glycine max , Hidrógeno , Bifenilos Policlorados , Simbiosis , Bifenilos Policlorados/metabolismo , Simbiosis/fisiología , Glycine max/metabolismo , Glycine max/microbiología , Hidrógeno/metabolismo , Rhizobium/fisiología , Biotransformación , Bradyrhizobium/metabolismo , Bradyrhizobium/fisiología , Biodegradación Ambiental
4.
mSystems ; 9(7): e0035424, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38842321

RESUMEN

Beneficial interactions between plants and rhizosphere fungi can enhance plant adaptability during drought stress. However, harnessing these interactions will require an in-depth understanding of the response of fungal community assembly to drought. Herein, by using different varieties of wheat plants, we analyzed the drought-induced changes in fungal community assembly in rhizosphere and bulk soil. We demonstrated that drought significantly altered the fungal communities, with the contribution of species richness to community beta diversity increased in both rhizosphere and bulk soil compartments during drought stress. The stochastic processes dominated fungal community assembly, but the relative importance of deterministic processes, mainly homogeneous selection, increased in the drought-stressed rhizosphere. Drought induced an increase in the relative abundance of generalists in the rhizosphere, as opposed to specialists, and the top 10 abundant taxa that enriched under drought conditions were predominantly generalists. Notably, the most abundant drought-enriched taxon in rhizosphere was a generalist, and the corresponding Chaetomium strain was found capable of improving root length and activating ABA signaling in wheat plants through culture-based experiment. Together, these findings provide evidence that host plants exert a strong influence on rhizospheric fungal community assembly during stress and suggest the fungal communities that have experienced drought have the potential to confer fitness advantages to the host plants. IMPORTANCE: We have presented a framework to integrate the shifts in community assembly processes with plant-soil feedback during drought stress. We found that environmental filtering and host plant selection exert influence on the rhizospheric fungal community assembly, and the re-assembled community has great potential to alleviate plant drought stress. Our study proposes that future research should incorporate ecology with plant, microbiome, and molecular approaches to effectively harness the rhizospheric microbiome for enhancing the resilience of crop production to drought.


Asunto(s)
Sequías , Micobioma , Rizosfera , Microbiología del Suelo , Triticum , Triticum/microbiología , Triticum/crecimiento & desarrollo , Hongos/fisiología , Desarrollo de la Planta/fisiología , Raíces de Plantas/microbiología , Estrés Fisiológico
5.
Sci Rep ; 14(1): 2677, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302642

RESUMEN

Cellular automata (CA) are computational systems that exhibit complex global behavior arising from simple local rules, making them a fascinating candidate for various research areas. However, challenges such as limited flexibility and efficiency on conventional hardware platforms still exist. In this study, we propose a memristor-based circuit for implementing elementary cellular automata (ECA) by extending the stateful three-memristor logic operations derived from material implication (IMP) logic gates. By leveraging the inherent physical properties of memristors, this approach offers simplicity, minimal operational steps, and high flexibility in implementing ECA rules by adjusting the circuit parameters. The mathematical principles governing circuit parameters are analyzed, and the evolution of multiple ECA rules is successfully demonstrated, showcasing the robustness in handling the stochastic nature of memristors. This approach provides a hardware solution for ECA implementation and opens up new research opportunities in the hardware implementation of CA.

7.
Chemosphere ; 344: 140383, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37832891

RESUMEN

Polyethylene (PE) mulch films have been widely used in agriculture and led to a significant pollution in cultivated soils. It is desirable to develop the sustainable method for the degradation of PE. As an environment friendly approach, microbial or enzymatic degradation of PE could meet this demanding. Thus, more microbial strains are required for illustrating biodegrading pathway and developing efficient biological method. In this study, Gordonia polyisoprenivorans B251 capable of degrading PE was isolated from bacterial enrichment with hexadecane as a sole carbon source for two years, in which genus Gordonia had dominated. As revealed by microbial growth curve, the strain B251 had the highest growth rate than other tested strains in the mediums either with hexadecane or PE particles as sole carbon source. The formation of biofilms in both enriched culture and G. polyisoprenivorans B251 pure culture attached to PE film was observed. The capability for PE degradation of individual strain was screened by 30-day incubation with PE film and confirmed by the presence of hydroxyl, carbonyl, carbon-carbon double bond and ether groups in FT-IR analysis and cracks on the surface of PE film observed by scanning electron microscopy (SEM). Therefore, Gordonia polyisoprenivorans, reported as their degradation of environmental contaminants in previous study, were also identified in current study as a candidate for polyethylene biodegradation.


Asunto(s)
Bacterias , Polietileno , Polietileno/química , Espectroscopía Infrarroja por Transformada de Fourier , Biodegradación Ambiental , Biopelículas , Carbono
8.
Artículo en Inglés | MEDLINE | ID: mdl-37691198

RESUMEN

AIMS: This study aims to evaluate the efficacy and safety of PARP inhibitor therapy in advanced ovarian cancer and identify the optimal treatment for the survival of patients. BACKGROUND: The diversity of PARP inhibitors makes clinicians confused about the optimal strategy and the most effective BRCAm mutation-based regimen for the survival of patients with advanced ovarian cancer. OBJECTIVES: The objective of this study is to compare the effects of various PARP inhibitors alone or in combination with other agents in advanced ovarian cancer. METHODS: PubMed, Embase, Cochrane Library, and Web of Science were searched for relevant studies on PARP inhibitors for ovarian cancer. Bayesian network meta-analysis was performed using Stata 15.0 and R 4.0.4. The primary outcome was the overall PFS, and the secondary outcomes included OS, AE3, DISAE, and TFST. RESULTS: Fifteen studies involving 5,788 participants were included. The Bayesian network metaanalysis results showed that olaparibANDAI was the most beneficial in prolonging overall PFS and non-BRCAm PFS, followed by niraparibANDAI. However, for BRCAm patients, olaparibTR might be the most effective, followed by niraparibANDAI. Olaparib was the most effective for the OS of BRCAm patients. AI, olaparibANDAI, and veliparibTR were more likely to induce grade 3 or higher adverse events. AI and olaparibANDAI were more likely to cause DISAE. CONCLUSION: PARP inhibitors are beneficial to the survival of patients with advanced ovarian cancer. The olaparibTR is the most effective for BRCAm patients, whereas olaparibANDAI and niraparibANDAI are preferable for non-BRCAm patients. Other: More high-quality studies are desired to investigate the efficacy and safety of PARP inhibitors in patients with other genetic performances.

9.
ISME J ; 17(12): 2169-2181, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37775536

RESUMEN

Nitrogen is a limiting nutrient for degraders function in hydrocarbon-contaminated environments. Biological nitrogen fixation by diazotrophs is a natural solution for supplying bioavailable nitrogen. Here, we determined whether the diazotroph Azotobacter chroococcum HN can provide nitrogen to the polycyclic aromatic hydrocarbon-degrading bacterium Paracoccus aminovorans HPD-2 and further explored the synergistic interactions that facilitate pyrene degradation in nitrogen-deprived environments. We found that A. chroococcum HN and P. aminovorans HPD-2 grew and degraded pyrene more quickly in co-culture than in monoculture. Surface-enhanced Raman spectroscopy combined with 15N stable isotope probing (SERS - 15N SIP) demonstrated that A. chroococcum HN provided nitrogen to P. aminovorans HPD-2. Metabolite analysis and feeding experiments confirmed that cross-feeding occurred between A. chroococcum HN and P. aminovorans HPD-2 during pyrene degradation. Transcriptomic and metabolomic analyses further revealed that co-culture significantly upregulated key pathways such as nitrogen fixation, aromatic compound degradation, protein export, and the TCA cycle in A. chroococcum HN and quorum sensing, aromatic compound degradation and ABC transporters in P. aminovorans HPD-2. Phenotypic and fluorescence in situ hybridization (FISH) assays demonstrated that A. chroococcum HN produced large amounts of biofilm and was located at the bottom of the biofilm in co-culture, whereas P. aminovorans HPD-2 attached to the surface layer and formed a bridge-like structure with A. chroococcum HN. This study demonstrates that distinct syntrophic interactions occur between A. chroococcum HN and P. aminovorans HPD-2 and provides support for their combined use in organic pollutant degradation in nitrogen-deprived environments.


Asunto(s)
Fijación del Nitrógeno , Nitrógeno , Nitrógeno/metabolismo , Hibridación Fluorescente in Situ , Pirenos
10.
J Phys Condens Matter ; 35(36)2023 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-37267987

RESUMEN

Effect of the internal interface layer on the dielectric properties of doped Ba0.6Sr0.4TiO3(BST) films and their simulation research in filters. Based on the interfacial effect in the multi-layer ferroelectric thin film, a different number of internal interface layers was proposed and introduced into the Ba0.6Sr0.4TiO3thin film. First, Ba0.6Sr0.4Ti0.99Zn0.01O3(ZBST) sol and Ba0.6Sr0.4Ti0.99Mg0.01O3(MBST) sols were prepared using the sol-gel method. Ba0.6Sr0.4Ti0.99Zn0.01O3/Ba0.6Sr0.4Ti0.99Mg0.01O3/Ba0.6Sr0.4Ti0.99Zn0.01O3thin films with 2 layer internal interface layer, 4 layer internal interface layer and 8 layer internal interface layer were designed and prepared (I2, I4, I8). The effects of the internal interface layer on the structure, morphology, dielectric properties, and leakage current behavior of the films were studied. The results showed that all the films were of the cubic perovskite BST phase and had the strongest diffraction peak in the (110) crystal plane. The surface composition of the film was uniform, and there was no cracked layer. When the bias of the applied DC field was 600 kV cm-1, the high-quality factor values of the I8 thin film at 10 MHz and 100 kHz were 111.3 and 108.6, respectively. The introduction of the internal interface layer changed the leakage current of the Ba0.6Sr0.4TiO3thin film, and the I8 thin film exhibited the minimum leakage current density. The I8 thin-film capacitor was used as the tunable element to design a fourth-step 'tapped' complementary bandpass filter. When the permittivity was reduced from 500 to 191, the central frequency-tunable rate of the filter was 5.7%.

11.
Front Neurosci ; 17: 1192993, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37351423

RESUMEN

Working memory refers to the brain's ability to store and manipulate information for a short period. It is disputably considered to rely on two mechanisms: sustained neuronal firing, and "activity-silent" working memory. To develop a highly biologically plausible neuromorphic computing system, it is anticipated to physically realize working memory that corresponds to both of these mechanisms. In this study, we propose a memristor-based neural network to realize the sustained neural firing and activity-silent working memory, which are reflected as dual functional states within memory. Memristor-based synapses and two types of artificial neurons are designed for the Winner-Takes-All learning rule. During the cognitive task, state transformation between the "focused" state and the "unfocused" state of working memory is demonstrated. This work paves the way for further emulating the complex working memory functions with distinct neural activities in our brains.

12.
Nat Plants ; 9(6): 908-925, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37142750

RESUMEN

Genetic transformation is important for gene functional study and crop improvement. However, it is less effective in wheat. Here we employed a multi-omic analysis strategy to uncover the transcriptional regulatory network (TRN) responsible for wheat regeneration. RNA-seq, ATAC-seq and CUT&Tag techniques were utilized to profile the transcriptional and chromatin dynamics during early regeneration from the scutellum of immature embryos in the wheat variety Fielder. Our results demonstrate that the sequential expression of genes mediating cell fate transition during regeneration is induced by auxin, in coordination with changes in chromatin accessibility, H3K27me3 and H3K4me3 status. The built-up TRN driving wheat regeneration was found to be dominated by 446 key transcription factors (TFs). Further comparisons between wheat and Arabidopsis revealed distinct patterns of DNA binding with one finger (DOF) TFs in the two species. Experimental validations highlighted TaDOF5.6 (TraesCS6A02G274000) and TaDOF3.4 (TraesCS2B02G592600) as potential enhancers of transformation efficiency in different wheat varieties.


Asunto(s)
Factores de Transcripción , Triticum , Triticum/genética , Triticum/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Cromatina , Redes Reguladoras de Genes , Diferenciación Celular
13.
Sensors (Basel) ; 23(5)2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36904605

RESUMEN

Processing-in-Memory (PIM) based on Resistive Random Access Memory (RRAM) is an emerging acceleration architecture for artificial neural networks. This paper proposes an RRAM PIM accelerator architecture that does not use Analog-to-Digital Converters (ADCs) and Digital-to-Analog Converters (DACs). Additionally, no additional memory usage is required to avoid the need for a large amount of data transportation in convolution computation. Partial quantization is introduced to reduce the accuracy loss. The proposed architecture can substantially reduce the overall power consumption and accelerate computation. The simulation results show that the image recognition rate for the Convolutional Neural Network (CNN) algorithm can reach 284 frames per second at 50 MHz using this architecture. The accuracy of the partial quantization remains almost unchanged compared to the algorithm without quantization.

14.
Genome Biol ; 24(1): 7, 2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36639687

RESUMEN

BACKGROUND: Plant and animal embryogenesis have conserved and distinct features. Cell fate transitions occur during embryogenesis in both plants and animals. The epigenomic processes regulating plant embryogenesis remain largely elusive. RESULTS: Here, we elucidate chromatin and transcriptomic dynamics during embryogenesis of the most cultivated crop, hexaploid wheat. Time-series analysis reveals stage-specific and proximal-distal distinct chromatin accessibility and dynamics concordant with transcriptome changes. Following fertilization, the remodeling kinetics of H3K4me3, H3K27ac, and H3K27me3 differ from that in mammals, highlighting considerable species-specific epigenomic dynamics during zygotic genome activation. Polycomb repressive complex 2 (PRC2)-mediated H3K27me3 deposition is important for embryo establishment. Later H3K27ac, H3K27me3, and chromatin accessibility undergo dramatic remodeling to establish a permissive chromatin environment facilitating the access of transcription factors to cis-elements for fate patterning. Embryonic maturation is characterized by increasing H3K27me3 and decreasing chromatin accessibility, which likely participates in restricting totipotency while preventing extensive organogenesis. Finally, epigenomic signatures are correlated with biased expression among homeolog triads and divergent expression after polyploidization, revealing an epigenomic contributor to subgenome diversification in an allohexaploid genome. CONCLUSIONS: Collectively, we present an invaluable resource for comparative and mechanistic analysis of the epigenomic regulation of crop embryogenesis.


Asunto(s)
Cromatina , Histonas , Animales , Histonas/metabolismo , Triticum/genética , Triticum/metabolismo , Desarrollo Embrionario/genética , Complejo Represivo Polycomb 2/metabolismo , Mamíferos/genética
15.
Sci Total Environ ; 823: 153547, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35101510

RESUMEN

Although the plant-growth promotion by algae have been studied comprehensively, their impacts on indigenous soil microbiome remain largely unexplored. Herein we conducted a greenhouse experiment to investigate the changes in soil properties and corresponding microbial communities (bacterial, fungal and protists) after 2-year application of algae and their dynamic variation within 60 days immediately after algae addition. In comparison with Control treatment, the impact of algae on soil properties and microbial communities was huge, especially the content of nitrate was decreased however soluble organic nitrogen (SON) was increased. The increased copies of nifH gene suggested the improved potential of nitrogen fixation in algae treated soil. By constructing multitrophic ecological network, soil microorganisms were divided into several modules, and two key-stone microbial taxa (module 1 and 2) showed strong associations with the content of nitrate and SON. With addition of algae, the abundance of most microbial taxa was decreased and increased in module 1 and module 2, respectively. Particularly, module 1 and module 2 were proved to be taxonomically and functionally comprised of different microbes. Moreover, random forest analysis and structural equation model indicated that the key-stone microbial taxa were more important factors affecting the content of nitrate and SON than algae, bacterial, fungal and protistan communities and the influence of algae on soil nitrogen cycling mostly depended on their indirect effects via module 1 and 2.


Asunto(s)
Nitrógeno , Suelo , Hongos/genética , Nitrógeno/análisis , Plantas , Suelo/química , Microbiología del Suelo
16.
Plant Cell Environ ; 45(3): 969-984, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34800291

RESUMEN

Rhizosphere microorganisms interact with plant roots by producing chemical signals that regulate root development. However, the distinct bioactive compounds and signal transduction pathways remain to be identified. Here, we showed that sesquiterpenes are the main volatile compounds produced by plant-beneficial Trichoderma guizhouense NJAU4742. Inhibition of sesquiterpene biosynthesis eliminated the promoting effect of this strain on root growth, indicating its involvement in plant-fungus cross-kingdom signalling. Sesquiterpene component analysis identified cedrene, a highly abundant sesquiterpene in strain NJAU4742, to stimulate plant growth and root development. Genetic analysis and auxin transport inhibition showed that the TIR1 and AFB2 auxin receptors, IAA14 auxin-responsive protein, and ARF7 and ARF19 transcription factors affected the response of lateral roots to cedrene. Moreover, the AUX1 auxin influx carrier and PIN2 efflux carrier were also found to be indispensable for cedrene-induced lateral root formation. Confocal imaging showed that cedrene affected the expression of pPIN2:PIN2:GFP and pPIN3:PIN3:GFP, which might be related to the effect of cedrene on root morphology. These results suggested that a novel sesquiterpene molecule from plant-beneficial T. guizhouense regulates plant root development through the transport and signalling of auxin.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Hypocreales , Ácidos Indolacéticos/metabolismo , Raíces de Plantas/metabolismo , Sesquiterpenos Policíclicos , Transducción de Señal
17.
Am J Orthod Dentofacial Orthop ; 159(5): 666-681.e2, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33653641

RESUMEN

Treatment of orthodontic patients with temporomandibular disorder (TMD) is challenging for orthodontists because of the TMD signs and symptoms and unstable mandible position, which may lead to improper diagnosis and treatment design. This case report presents a 22-year-old woman with proclined maxillary incisors and TMD. First, stabilization splint therapy was implemented to eliminate temporomandibular joint pain and to obtain the stable adapted centric posture. Subsequently, orthodontic treatment was initiated on the basis of a definitive diagnosis made from the postsplint records. Temporary anchorage devices were used to intrude maxillary molars and distalize the maxillary dental arch. Favorable soft tissue, skeletal, and dental relationship were accomplished after 12 months of comprehensive orthodontic treatment. Functional occlusion was established with teeth as well as vacuum-formed retainers. Excellent posttreatment stability was maintained after a 20-month retention.


Asunto(s)
Férulas (Fijadores) , Trastornos de la Articulación Temporomandibular , Adulto , Cefalometría , Protocolos Clínicos , Femenino , Humanos , Mandíbula , Trastornos de la Articulación Temporomandibular/diagnóstico , Trastornos de la Articulación Temporomandibular/terapia , Adulto Joven
18.
Acta Biomater ; 123: 364-378, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33453407

RESUMEN

The existing approaches for healing mandibular condylar osteochondral defects, which are prevalent in temporomandibular joint disorders (TMD), are sparse and not reparative. To address this, regenerative medicine in situ has transpired as a potential therapeutic solution as it can effectively regenerate composite tissues. Herein, injectable self-crosslinking thiolated hyaluronic acid (HA-SH)/type I collagen (Col I) blend hydrogel and BCP ceramics combined with rabbit bone mesenchymal stem cells (rBMSCs)/chondrocytes were used to fabricate a new bi-layer scaffold to simulate specific structure of rabbit condylar osteochondral defects. The in vitro results demonstrated that the blend hydrogel scaffold provided suitable microenvironment for simultaneously realizing proliferation and chondrogenic specific matrix secretion of both rBMSCs and chondrocytes, while BCP ceramics facilitated rBMSCs proliferation and osteogenic differentiation. The in vivo results confirmed that compared with cell-free implant, the rBMSCs/chondrocytes-loaded bi-layer scaffold could effectively promote the regeneration of both fibrocartilage and subchondral bone, suggesting that the bi-layer scaffold presented a promising option for cell-mediated mandibular condylar cartilage regeneration.


Asunto(s)
Hidrogeles , Ingeniería de Tejidos , Animales , Cerámica/farmacología , Condrocitos , Hidrogeles/farmacología , Osteogénesis , Conejos , Andamios del Tejido
19.
Angle Orthod ; 91(3): 399-415, 2021 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-33373430

RESUMEN

Treatment of skeletal Class II patients with dual bite and idiopathic condylar resorption (ICR) is challenging for orthodontists because of the unstable position of the mandible as well as skeletal relapse attributed to improper seating of the mandibular condyles. This case report describes the successful treatment of an 18-year-old Mongolian man diagnosed with centric relation-maximum intercuspation discrepancy and ICR. After making a definitive diagnosis from verified centric relation using bilateral manipulation, orthodontic treatment was initiated followed by three-dimensional computer-aided design/computer-aided manufacturing prebent titanium plate-guided sagittal split ramus osteotomy and genioplasty. Postoperative 3D superimposition demonstrated that this surgical guide approach provided accurate repositioning of the condyles, which were well positioned in the fossae. Complete orthodontic and surgical treatment time was 24 months. The patient's facial appearance and occlusion improved significantly, and a stable result was obtained with a 1-year follow-up.


Asunto(s)
Maloclusión de Angle Clase III , Maloclusión Clase II de Angle , Procedimientos Quirúrgicos Ortognáticos , Adolescente , Cefalometría , Humanos , Masculino , Maloclusión Clase II de Angle/complicaciones , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/cirugía , Mandíbula , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/cirugía , Osteotomía Sagital de Rama Mandibular
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