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1.
Sensors (Basel) ; 24(2)2024 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-38276378

RESUMO

In factories, human posture recognition facilitates human-machine collaboration, human risk management, and workflow improvement. Compared to optical sensors, inertial sensors have the advantages of portability and resistance to obstruction, making them suitable for factories. However, existing product-level inertial sensing solutions are generally expensive. This paper proposes a low-cost human motion capture system based on BMI 160, a type of six-axis inertial measurement unit (IMU). Based on WIFI communication, the collected data are processed to obtain the displacement of human joints' rotation angles around XYZ directions and the displacement in XYZ directions, then the human skeleton hierarchical relationship was combined to calculate the real-time human posture. Furthermore, the digital human model was been established on Unity3D to synchronously visualize and present human movements. We simulated assembly operations in a virtual reality environment for human posture data collection and posture recognition experiments. Six inertial sensors were placed on the chest, waist, knee joints, and ankle joints of both legs. There were 16,067 labeled samples obtained for posture recognition model training, and the accumulated displacement and the rotation angle of six joints in the three directions were used as input features. The bi-directional long short-term memory (BiLSTM) model was used to identify seven common operation postures: standing, slightly bending, deep bending, half-squatting, squatting, sitting, and supine, with an average accuracy of 98.24%. According to the experiment result, the proposed method could be used to develop a low-cost and effective solution to human posture recognition for factory operation.


Assuntos
Captura de Movimento , Postura , Humanos , Fenômenos Biomecânicos , Movimento , Rotação , Movimento (Física)
2.
Virus Res ; 339: 199270, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-37972855

RESUMO

Vibrio is a prevalent bacterial genus in aquatic environments and exhibits diverse metabolic capabilities, playing a vital role in marine biogeochemical cycles. This study isolated a novel virus infecting Vibrio cyclitrophicus, vB_VviC_ZQ26, from coastal waters near Qingdao, China. The vB_VviC_ZQ26 comprises a linear double-stranded DNA genome with a length of 42,982 bp and a G + C content of 43.21 %, encoding 72 putative open reading frames (ORFs). Transmission electron microscope characterization indicates a siphoviral-morphology of vB_VviC_ZQ26. Nucleic-acids-wide analysis indicates a tetranucleotide frequency deviation for genomic segments encoding putative gene transfer agent protein (GTA) and coil-containing protein, implying divergent origins occurred in different parts of viral genomes. Phylogenetic and genome-content-based analysis suggest that vB_VviC_ZQ26 represents a novel vibriophage-specific family designated as Coheviridae. From the result of biogeographic analysis, Coheviridae is mainly colonized in the temperate and tropical epipelagic zones. This study describes a novel vibriophage infecting V. cyclitrophicus, shedding light on the evolutionary divergence of different parts of the viral genome and its ecological footprint in marine environments.


Assuntos
Bacteriófagos , Vibrio , Filogenia , Vibrio/genética , DNA , Genoma Viral , Fases de Leitura Aberta , DNA Viral/genética
3.
Sensors (Basel) ; 23(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38067781

RESUMO

As space resources become increasingly constrained, the major space-faring nations are establishing large space target monitoring systems. There is a demand for both the number and the detection capability of space-based optical monitoring equipment. The detection range (i.e., field of view) and parasitic capability (lightweight and small size) of a single optical payload will largely reduce the scale and cost of the monitoring system. Therefore, in this paper, the optic-mechanical system of an ultra-lightweight and ultra-compact space camera and the optical alignment method are investigated around a fully freeform off-axis triple-reversal large field of view (FOV) optical system. The optic-mechanical system optimisation design is completed by adopting the optic-mechanical integration analysis method, and the weight of the whole camera is less than 10 kg. In addition, to address the mounting problems caused by the special characteristics of the freeform surface optical system, a dual CGH coreference alignment method is innovatively proposed. The feasibility of the method is verified by the mounting and testing test, and the test results show that the system wavefront difference is better than 1/10 λ. The imaging test of the space camera and the magnitude test results meet the design requirements of the optical system. The optic-mechanical system design method and alignment method proposed in this paper are instructive for the design and engineering of large field of view full freeform optical loads.

4.
Proc Natl Acad Sci U S A ; 120(36): e2307356120, 2023 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-37639585

RESUMO

The nuclear envelope (NE) separates genomic DNA from the cytoplasm and regulates transport between the cytosol and the nucleus in eukaryotes. Nuclear stiffening enables the cell nucleus to protect itself from extensive deformation, loss of NE integrity, and genome instability. It is known that the reorganization of actin, lamin, and chromatin can contribute to nuclear stiffening. In this work, we show that structural alteration of NE also contributes to instantaneous nuclear stiffening under indentation. In situ mechanical characterization of cell nuclei in intact cells shows that nuclear stiffening and unfolding of NE wrinkles occur simultaneously at the indentation site. A positive correlation between the initial state of NE wrinkles, the unfolding of NE wrinkles, and the stiffening ratio (stiffness fold-change) is found. Additionally, NE wrinkles unfold throughout the nucleus outside the indentation site. Finite element simulation, which involves the purely passive process of structural unfolding, shows that unfolding of NE wrinkles alone can lead to an increase in nuclear stiffness and a reduction in stress and strain levels. Together, these results provide a perspective on how cell nucleus adapts to mechanical stimuli through structural alteration of the NE.


Assuntos
Núcleo Celular , Membrana Nuclear , Cromatina , Citosol , Citoplasma
5.
Front Microbiol ; 14: 1231279, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37601358

RESUMO

Cyanophages play a crucial role in the biogeochemical cycles of aquatic ecosystems by affecting the population dynamics and community structure of cyanobacteria. In this study, a novel cyanophage, Nanhaivirus ms29, that infects Synechococcus sp. MW02 was isolated from the ocean basin in the South China Sea. It was identified as a T4-like phage using transmission electron microscopy. Phylogenetic analysis demonstrated that this cyanophage is distinct from other known T4-like cyanophage, belonging to a novel genus named Nanhaivirus within the family Kyanoviridae, according to the most recent classification proposed by the International Committee on Taxonomy of Viruses (ICTV). The genome of this novel cyanophage is composed of 178,866 bp of double-stranded DNA with a G + C content of 42.5%. It contains 217 potential open reading frames (ORFs) and 6 tRNAs. As many as 30 auxiliary metabolic genes (AMGs) were identified in the genome, which related to photosynthesis, carbon metabolism, nutrient uptake and stress tolerance, possibly reflecting a genomic adaption to the oligotrophic environment. Read-mapping analysis showed that Nanhaivirus ms29 mainly distributed in temperate and tropical epipelagic waters. This study enriches of the virus gene database of cyanophages and provides valuable insights into the phylogeny of cyanophages and their interactions with their hosts.

6.
Sci Adv ; 9(13): eade5321, 2023 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-36989359

RESUMO

Glioblastoma (GBM) is the most common and aggressive primary brain cancer. Despite multimodal treatment including surgery, radiotherapy, and chemotherapy, median patient survival has remained at ~15 months for decades. This situation demands an outside-the-box treatment approach. Using magnetic carbon nanotubes (mCNTs) and precision magnetic field control, we report a mechanical approach to treat chemoresistant GBM. We show that GBM cells internalize mCNTs, the mobilization of which by rotating magnetic field results in cell death. Spatiotemporally controlled mobilization of intratumorally delivered mCNTs suppresses GBM growth in vivo. Functionalization of mCNTs with anti-CD44 antibody, which recognizes GBM cell surface-enriched antigen CD44, increases mCNT recognition of cancer cells, prolongs mCNT enrichment within the tumor, and enhances therapeutic efficacy. Using mouse models of GBM with upfront or therapy-induced resistance to temozolomide, we show that mCNT treatment is effective in treating chemoresistant GBM. Together, we establish mCNT-based mechanical nanosurgery as a treatment option for GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Nanotubos de Carbono , Camundongos , Animais , Glioblastoma/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/metabolismo , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Morte Celular , Linhagem Celular Tumoral
7.
Nano Lett ; 23(6): 2321-2331, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36893018

RESUMO

Emerging heart-on-a-chip technology is a promising tool to establish in vitro cardiac models for therapeutic testing and disease modeling. However, due to the technical complexity of integrating cell culture chambers, biosensors, and bioreactors into a single entity, a microphysiological system capable of reproducing controlled microenvironmental cues to regulate cell phenotypes, promote iPS-cardiomyocyte maturity, and simultaneously measure the dynamic changes of cardiomyocyte function in situ is not available. This paper reports an ultrathin and flexible bioelectronic array platform in 24-well format for higher-throughput contractility measurement under candidate drug administration or defined microenvironmental conditions. In the array, carbon black (CB)-PDMS flexible strain sensors were embedded for detecting iPSC-CM contractility signals. Carbon fiber electrodes and pneumatic air channels were integrated to provide electrical and mechanical stimulation to improve iPSC-CM maturation. Performed experiments validate that the bioelectronic array accurately reveals the effects of cardiotropic drugs and identifies mechanical/electrical stimulation strategies for promoting iPSC-CM maturation.


Assuntos
Técnicas Biossensoriais , Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Técnicas de Cultura de Células , Preparações Farmacêuticas , Diferenciação Celular
8.
Minerva Surg ; 78(4): 371-377, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36940109

RESUMO

BACKGROUND: The aim of this study was to observe the alveolar bone height changes in the anterior tooth region after orthodontic treatment for Angle's Class II division 1 malocclusion. METHODS: Ninety-three patients treated from January 2015 to December 2019 were retrospectively analyzed, of whom 48 received tooth extraction and 45 did not. RESULTS: After orthodontic treatment, the alveolar bone heights in the anterior tooth regions of tooth extraction and non-extraction groups decreased by 67.31% and 66.94%, respectively. Except for the maxillary and mandibular canines in the tooth extraction group as well as the labial side of maxillary anterior teeth and the palatal side of maxillary central incisors of the non-extraction group, the alveolar bone heights of other sites significantly reduced (P<0.05). The reduction in the alveolar bone height of the tooth extraction group significantly exceeded that of the non-extraction group on the palatal side of maxillary incisors and the lingual side of mandibular anterior teeth (P<0.05). CONCLUSIONS: Alveolar bone height in the anterior tooth region decreases after orthodontic treatment for Angle's Class II division 1 malocclusion, being closely related to tooth position together with movement direction and amplitude.


Assuntos
Assistência Odontológica , Má Oclusão Classe II de Angle , Humanos , Incisivo/diagnóstico por imagem , Má Oclusão Classe II de Angle/diagnóstico por imagem , Má Oclusão Classe II de Angle/terapia , Estudos Retrospectivos , Extração Dentária
9.
Virus Res ; 328: 199072, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36781075

RESUMO

Cyanophages are known to influence the population dynamics and community structure of cyanobacteria and thus play an important role in biogeochemical cycles in aquatic ecosystems. In this study, a novel Synechococcus phage S-H9-2 infecting Synechococcus sp. WH 8102 was isolated from the coastal water of the Yellow Sea. Synechococcus phage S-H9-2 contains a 187,320 bp genome of double-stranded DNA with a G + C content of 40.3%, 202 potential open reading frames (ORFs), and 15 tRNAs. Phylogenetic analysis and nucleotide-based intergenomic similarity suggest that Synechococcus phage S-H9-2 belongs to the Bristolvirus genus under the family Kyanoviridae. Homologs of the S-H9-2 open reading frame can be found in a variety of marine environments, as shown by the results of mapping the genome sequence of S-H9-2 to the Global Ocean Viromes 2.0 dataset. The presence of auxiliary metabolic genes (AMGs) related to photosynthesis, carbon metabolism, and phosphorus assimilation, as well as phylogenetic relationships based on complete genome sequences, reflect the mechanism of phage-host interaction and host-specific strategies for adaptation to environmental conditions. This study enriches the current genomic database of cyanophage and contributed to our understanding of the virus-host interactions and their adaption to the environment.


Assuntos
Bacteriófagos , Synechococcus , Synechococcus/genética , Filogenia , Ecossistema , Genoma Viral , Genômica
10.
Materials (Basel) ; 15(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36431689

RESUMO

Polyurethane elastomers are anticipated to be applied in the field of cavitation erosion (CE) resistance, but their protection and damage mechanisms are not clear, which greatly restricts their further development. In this article, five polyether polyurethanes (PUx) with different crosslinking densities were prepared. Their mechanical properties, thermal properties, water absorption, surface morphology and chemical structure before and after CE tests were compared with ESEM, OM, TG-DSC, FTIR and XPS in detail. The results showed that with an increase in crosslinking density, the tensile strength of PUx increased first and then decreased, elongation at break and water absorption reduced gradually and thermal decomposition temperature and adhesion strength increased steadily. During the CE process, cavitation load aggravated the degree of microphase separation and made brittle hard segments concentrate on the coating surface; meanwhile, cavitation heat accelerated hydrolysis, pyrolysis, oxidation and the fracture of molecular chains. As a result, the mechano-thermal coupling intensified the formation and propagation of fatigue cracks, which should be the fundamental reason for the CE damage of polyurethane elastomer. PU0.4 exhibited the best CE resistance among the five coatings thanks to its good comprehensive properties and may find potential applications on the surface of hydraulic components.

11.
ACS Nano ; 16(7): 10824-10839, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35786860

RESUMO

In cell biology, fluorescent dyes are routinely used for biochemical measurements. The traditional global dye treatment method suffers from low signal-to-noise ratios (SNR), especially when used for detecting a low concentration of ions, and increasing the concentration of fluorescent dyes causes more severe cytotoxicity. Here, we report a robotic technique that controls how a low amount of fluorescent-dye-coated magnetic nanoparticles accurately forms a swarm and increases the fluorescent dye concentration in a local region inside a cell for intracellular measurement. Different from existing magnetic micromanipulation systems that generate large swarms (several microns and above) or that cannot move the generated swarm to an arbitrary position, our system is capable of generating a small swarm (e.g., 1 µm) and accurately positioning the swarm inside a single cell (position control accuracy: 0.76 µm). In experiments, the generated swarm inside the cell showed an SNR 10 times higher than the traditional global dye treatment method. The high-SNR robotic swarm enabled intracellular measurements that had not been possible to achieve with traditional global dye treatment. The robotic swarm technique revealed an apparent pH gradient in a migrating cell and was used to measure the intracellular apparent pH in a single oocyte of living C. elegans. With the position control capability, the swarm was also applied to measure calcium changes at the perinuclear region of a cell before and after mechanical stimulation. The results showed a significant calcium increase after mechanical stimulation, and the calcium increase was regulated by the mechanically sensitive ion channel, PIEZO1.


Assuntos
Corantes Fluorescentes , Robótica , Animais , Razão Sinal-Ruído , Cálcio , Caenorhabditis elegans
12.
Sci Adv ; 8(29): eabm5752, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35857830

RESUMO

Inspired by the collective intelligence in natural swarms, microrobotic agents have been controlled to form artificial swarms for targeted drug delivery, enhanced imaging, and hyperthermia. Different from these well-investigated tasks, this work aims to develop microrobotic swarms for embolization, which is a clinical technique used to block blood vessels for treating tumors, fistulas, and arteriovenous malformations. Magnetic particle swarms were formed for selective embolization to address the low selectivity of the present embolization technique that is prone to cause complications such as stroke and blindness. We established an analytical model that describes the relationships between fluid viscosity, flow rate, branching angle, magnetic field strength, and swarm integrity, based on which an actuation strategy was developed to maintain the swarm integrity inside a targeted region under fluidic flow conditions. Experiments in microfluidic channels, ex vivo tissues, and in vivo porcine kidneys validated the efficacy of the proposed strategy for selective embolization.

13.
ACS Nano ; 16(7): 11278-11290, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35715006

RESUMO

Heart beating is triggered by the generation and propagation of action potentials through the myocardium, resulting in the synchronous contraction of cardiomyocytes. This process highlights the importance of electrical and mechanical coordination in organ function. Investigating the pathogenesis of heart diseases and potential therapeutic actions in vitro requires biosensing technologies which allow for long-term and simultaneous measurement of the contractility and electrophysiology of cardiomyocytes. However, the adoption of current biosensing approaches for functional measurement of in vitro cardiac models is hampered by low sensitivity, difficulties in achieving multifunctional detection, and costly manufacturing processes. Leveraging carbon-based nanomaterials, we developed a biosensing platform that is capable of performing on-chip and simultaneous measurement of contractility and electrophysiology of human induced pluripotent stem-cell-derived cardiomyocyte (iPSC-CM) monolayers. This platform integrates with a flexible thin-film cantilever embedded with a carbon black (CB)-PDMS strain sensor for high-sensitivity contraction measurement and four pure carbon nanotube (CNT) electrodes for the detection of extracellular field potentials with low electrode impedance. Cardiac functional properties including contractile stress, beating rate, beating rhythm, and extracellular field potential were evaluated to quantify iPSC-CM responses to common cardiotropic agents. In addition, an in vitro model of drug-induced cardiac arrhythmia was established to further validate the platform for disease modeling and drug testing.


Assuntos
Células-Tronco Pluripotentes Induzidas , Miócitos Cardíacos , Humanos , Miócitos Cardíacos/fisiologia , Células-Tronco Pluripotentes Induzidas/fisiologia , Células Cultivadas , Contração Miocárdica , Fenômenos Eletrofisiológicos , Diferenciação Celular
14.
Dev Dyn ; 251(5): 748-758, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34962674

RESUMO

SHP2, encoded by the PTPN11 gene, participates in multiple cell functions including cell proliferation, movement, and differentiation. PTPN11 loss-of-function and gain-of-function mutations are both associated with diseases, such as Noonan syndrome, whose manifestations include bone defects, suggesting a crucial role for SHP2 in the skeleton. However, the exact mechanisms by which SHP2 regulates bone development remain unclear. This review focuses on the current understanding of the regulation of SHP2 and highlights the vital roles of SHP2 in skeletal development, especially its roles in ossification. Overall, a better understanding of the functions of SHP2 in ossification will provide a new avenue to treat-related skeletal diseases.


Assuntos
Síndrome de Noonan , Osteogênese , Diferenciação Celular/genética , Mutação com Ganho de Função , Humanos , Mutação , Síndrome de Noonan/genética , Síndrome de Noonan/metabolismo , Osteogênese/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/genética , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo
15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-936401

RESUMO

Objective @# The purpose of this study was to clarify the regulatory effect and mechanism of Src homology-2 domain containing protein tyrosine phosphatase-2 (SHP2) on human periodontal ligament stem cell (hPDLSC) proliferation and osteogenic differentiation under inflammatory environment and to provide a new target for the treatment of periodontitis. @*Methods@#SHP2 was knocked down in hPDLSCs, and the transfection efficiency of SHP2 was detected by RT-qPCR and Western blot. An in vitro inflammatory environment was created using tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β). The effect of SHP2 knockdown on hPDLSC viability under normal and inflammatory conditions was detected by CCK-8, and the osteogenic capacity of hPDLSCs under normal and inflammatory conditions was detected by ALP staining, ALP activity, ARS staining, RT-qPCR and Western blot. The mechanism by which SHP2 knockdown affected the MAPK pathway and its downstream NF-κB pathway under inflammatory conditions was assessed by Western blot. @*Results@# Green fluorescence was observed after transfection for 72 h, and the titer of SHP2 shRNA recombinant lentivirus was 2.9×108 TU/mL. SHP2 expression was significantly downregulated in lentivirus-transfected cells, as demonstrated by Western blot and RT-qPCR (P<0.001). SHP2 knockdown inhibited hPDLSC proliferation to a certain extent and increased the expression of early osteogenic markers under normal conditions, including increased ALP activity and increased ALP and COL-1 expression (P<0.05). However, SHP2 knockdown exerted no effect on mineralized nodule formation. In the TNF-α- and IL-1β-induced inflammatory environment, SHP2 knockdown exerted no effect on hPDLSC proliferation (P>0.05). Osteogenic markers were upregulated (P<0.05), and mineralized nodules were significantly increased (P<0.05) after SHP2 knockdown. Western blot analysis showed that p65 phosphorylation and IκB-α degradation were reduced in SHP2-knockdown hPDLSCs in the inflammatory environment. Moreover, SHP2 knockdown significantly inhibited the expression of p-p38 and p-JNK MAPK, which represent pathways upstream of the NF-κB pathway (P<0.05). @*Conclusion @# SHP2 knockdown did not affect cell viability but promoted the osteogenic potential of hPDLSCs by inhibiting the MAPK/NF-κB-mediated signaling pathway under inflammatory environment.

16.
Small ; 17(37): e2103702, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34390185

RESUMO

Micromanipulation techniques that are capable of assembling nano/micromaterials into usable structures such as topographical micropatterns (TMPs) have proliferated rapidly in recent years, holding great promise in building artificial electronic and photonic microstructures. Here, a method is reported for forming TMPs based on optoelectronic tweezers in either "bottom-up" or "top-down" modes, combined with in situ photopolymerization to form permanent structures. This work demonstrates that the assembled/cured TMPs can be harvested and transferred to alternate substrates, and illustrates that how permanent conductive traces and capacitive circuits can be formed, paving the way toward applications in microelectronics. The integrated, optical assembly/preservation method described here is accessible, versatile, and applicable for a wide range of materials and structures, suggesting utility for myriad microassembly and microfabrication applications in the future.


Assuntos
Micromanipulação , Óptica e Fotônica , Eletrônica , Fótons
17.
Sensors (Basel) ; 21(7)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33805129

RESUMO

The design of compact hyperspectral cameras with high ground resolution and large field of view (FOV) is a challenging problem in the field of remote sensing. In this paper, the time-delayed integration (TDI) of the digital domain is applied to solve the issue of insufficient light energy brought by high spatial resolution, and a hyperspectral camera with linear variable filters suitable for digital domain TDI technology is further designed. The camera has a wavelength range of 450-950 nm, with an average spectral resolution of 10.2 nm. The paper also analyzed the effects of digital domain TDI on the signal-noise ratio (SNR) and the spectral resolution. During its working in orbits, we have obtained high-SNR images with a swath width of 150 km, and a ground sample distance (GSD) of 10 m @ 500 km. The design of the hyperspectral camera has an improved spatial resolution while reducing the cost.

18.
Stem Cells Dev ; 30(10): 548-559, 2021 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-33736461

RESUMO

Dental-tissue-derived stem cells have been used for tissue engineering owing to their ease of isolation and efficacy in in vitro and in vivo proliferation and differentiation. Nanohydroxyapatite/chitosan/gelatin (nHA/CG) three-dimensional porous scaffolds are promising for bone tissue engineering, especially jaw bone regeneration, because of their structural and functional similarity to natural bone. In our previous study, the efficiency of scaffolds with stem cell complexes in osteogenesis was confirmed in vivo in immunocompromised mice. However, studies on the bone regeneration efficiency of stem cell-seeded nHA/CG scaffolds using large animal jaw bone defect models have not been conducted. This study evaluated the bone regeneration potential of the nHA/CG scaffolds with transplanted human periodontal ligament stem cells (hPDLSCs) in critical-sized jaw bone defects in minipigs. The hPDLSCs isolated from periodontal ligaments of discarded teeth (postorthodontic purposes) were seeded onto the nHA/CG scaffolds. The scaffold was successfully synthesized according to our previous studies. Forty-eight critical-sized jaw bone defects were created in 12 minipigs. The defects were randomly assigned to one of three groups [scaffolds with seeded hPDLSCs (hPDLSCs/nHA/CG), only scaffold (nHA/CG), and a negative control group, ie, no cells and scaffolds implanted into defects] to investigate jaw bone regeneration. The bone regeneration capacities of the three groups were assessed for up to 12 weeks. The results showed that the hPDLSCs adhered well to the nHA/CG scaffold in vitro, and the cell-nHA/CG composites significantly increased new bone formation and generated large bones with normal architectures and vascularization in vivo compared to the nHA/CG and control groups. Immunohistochemistry staining showed that runt-related transcription factor 2 (Runx2) was highly expressed in the bone marrow formed in the hPDLSCs/nHA/CG group. This study provides strong evidence for future clinical applications of the nHA/CG scaffolds transplanted with hPDLSCs to regenerate the bone in large jaw bone defects.


Assuntos
Regeneração Óssea/fisiologia , Arcada Osseodentária/fisiopatologia , Transplante de Células-Tronco/métodos , Células-Tronco/citologia , Alicerces Teciduais/química , Animais , Regeneração Óssea/genética , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Células Cultivadas , Quitosana/química , Durapatita/química , Feminino , Gelatina/química , Expressão Gênica , Humanos , Arcada Osseodentária/metabolismo , Arcada Osseodentária/patologia , Osteogênese/genética , Osteogênese/fisiologia , Ligamento Periodontal/citologia , Porosidade , Células-Tronco/fisiologia , Suínos , Porco Miniatura , Engenharia Tecidual/métodos
19.
Curr Stem Cell Res Ther ; 15(1): 24-31, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31486757

RESUMO

Tissue damage repairing and regeneration is a research hot topic. Tissue engineering arises at the historic moment which is a defect repair compound composed of seed cells, tissue engineering scaffolds, and inducing factors. Stem cells have a limited growth period in vitro culture, and they have a pattern of replicating ageing, and these disadvantages are limiting the applications of stem cells in basic research and clinical treatment. The enhancement of stem cell differentiation ability is a difficult problem to overcome, and it is possible to enhance the differentiation ability of stem cells through histone modification so as to provide a more robust foundation for damage repairing and regeneration. Studies have shown that Histone Deacetylases (HDAC) inhibitors can improve mesenchymal stem cells in vitro induced in different directions, conversion efficiency, increasing the feasibility and safety of stem cell therapy and tissue engineering, to offer reference to promote the stem cell therapy in clinical application. Therefore, this paper mainly focusing on the usage and achievements of the deacetylase inhibitors in stem cell differentiation studies and their use and prospects in repair of bone tissue defects.


Assuntos
Doenças Ósseas/terapia , Osso e Ossos/fisiologia , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Transplante de Células-Tronco/métodos , Células-Tronco/fisiologia , Animais , Regeneração Óssea , Diferenciação Celular , Histonas/metabolismo , Humanos , Engenharia Tecidual
20.
J Oral Sci ; 61(2): 200-205, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31217371

RESUMO

This study was conducted to investigate the short-term effects of a self-ligating appliance for orthodontic treatment of severe adult periodontitis. Thirty patients diagnosed as severe periodontitis were recruited at Nanjing Stomatological Hospital, P. R.China, between January 2012 and January 2016. General clinical and demographic data were collected from the patients, all of whom were treated with a self-ligating appliance. Probing pocket depth (PPD), clinical attachment level (CAL), bleeding on probing (BOP) and plaque index (PI) were measured before appliance placement, and at 1 and 3 months after appliance placement, respectively. Results showed the rate of tooth loss, mean PPD, mean CAL and the BOP ratio were more favorable in healthy subjects than in the patients. Smokers accounted for a significantly higher proportion of the patients in comparison with the healthy subjects. Clinical outcomes revealed that both the mean PPD and mean CAL were significantly decreased compared with the baseline (P < 0.05). Furthermore, the percentage of BOP, PI and bone mineral density were also significantly decreased at 1 month after treatment (P < 0.05). The volume of gingival crevicular fluid, as well as the levels of alkaline phosphatase, aspartate aminotransferase and glutathione peroxidase, were significantly increased in the first month after treatment, being decreased at 2 months, and finally returning to normal in the third month. In summary, orthodontic treatment using a self-ligating appliance can apparently improve the periodontal condition of patients with severe adult periodontitis.


Assuntos
Periodontite Crônica , Adulto , China , Índice de Placa Dentária , Líquido do Sulco Gengival , Humanos , Perda da Inserção Periodontal , Índice Periodontal
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