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1.
Cell ; 170(2): 367-381.e20, 2017 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-28709003

RESUMEN

High-order chromatin structure plays important roles in gene expression regulation. Knowledge of the dynamics of 3D chromatin structures during mammalian embryo development remains limited. We report the 3D chromatin architecture of mouse gametes and early embryos using an optimized Hi-C method with low-cell samples. We find that mature oocytes at the metaphase II stage do not have topologically associated domains (TADs). In sperm, extra-long-range interactions (>4 Mb) and interchromosomal interactions occur frequently. The high-order structures of both the paternal and maternal genomes in zygotes and two-cell embryos are obscure but are gradually re-established through development. The establishment of the TAD structure requires DNA replication but not zygotic genome activation. Furthermore, unmethylated CpGs are enriched in A compartment, and methylation levels are decreased to a greater extent in A compartment than in B compartment in embryos. In summary, the global reprogramming of chromatin architecture occurs during early mammalian development.


Asunto(s)
Cromatina/metabolismo , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario , Animales , Cromatina/química , Islas de CpG , Metilación de ADN , Replicación del ADN , Embrión de Mamíferos/química , Epigénesis Genética , Femenino , Células Germinativas/metabolismo , Masculino , Metafase , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Oocitos/citología , Espermatozoides/metabolismo , Cigoto/metabolismo
2.
Nature ; 576(7786): 306-310, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31801998

RESUMEN

In the interphase of the cell cycle, chromatin is arranged in a hierarchical structure within the nucleus1,2, which has an important role in regulating gene expression3-6. However, the dynamics of 3D chromatin structure during human embryogenesis remains unknown. Here we report that, unlike mouse sperm, human sperm cells do not express the chromatin regulator CTCF and their chromatin does not contain topologically associating domains (TADs). Following human fertilization, TAD structure is gradually established during embryonic development. In addition, A/B compartmentalization is lost in human embryos at the 2-cell stage and is re-established during embryogenesis. Notably, blocking zygotic genome activation (ZGA) can inhibit TAD establishment in human embryos but not in mouse or Drosophila. Of note, CTCF is expressed at very low levels before ZGA, and is then highly expressed at the ZGA stage when TADs are observed. TAD organization is significantly reduced in CTCF knockdown embryos, suggesting that TAD establishment during ZGA in human embryos requires CTCF expression. Our results indicate that CTCF has a key role in the establishment of 3D chromatin structure during human embryogenesis.


Asunto(s)
Factor de Unión a CCCTC/metabolismo , Cromatina , Factor de Unión a CCCTC/genética , Embrión de Mamíferos , Desarrollo Embrionario , Regulación de la Expresión Génica , Humanos , Masculino , Espermatozoides/metabolismo
3.
Am J Orthod Dentofacial Orthop ; 166(1): 50-60, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38639703

RESUMEN

INTRODUCTION: This study aimed to evaluate the effects of varying auxiliaries on tooth movement and stress distribution when maxillary central incisors were torqued 1° with a clear aligner through finite element analysis. METHODS: Three-dimensional finite element models, including maxillary alveolar bone, periodontal ligament, dentition, and clear aligner, were constructed. According to the auxiliaries designed on the maxillary central incisor, 5 models were created: (1) without auxiliaries (control model), (2) with the power ridge, (3) with the semi-ellipsoid attachment, (4) with the horizontal rectangular attachment, and (5) with the horizontal cylinder attachment. The tooth movement and periodontal ligament stress distribution after a palatal root torque of 1° were analyzed for each of the 5 models. RESULTS: With 1° torque predicted, the maxillary central incisor without auxiliaries showed a tendency of labial tipping, mesial tipping, and intrusion. The rotation center moved occlusally in the power ridge model. The labiolingual inclination variation increased in the semi-ellipsoid attachment model but decreased in the power ridge model. The maxillary central incisor is twisted in the distal direction in the power ridge model. The maxillary central incisor of the horizontal rectangular attachment and the horizontal cylinder attachment model behaved similarly to the control model. Periodontal stresses were concentrated in the cervical and apical areas. The maximum von Mises stresses were 11.6, 12.4, 3.81, 1.14, and 11.0 kPa in the 5 models. The semi-ellipsoid attachment model exhibited a more uniform stress distribution than the other models. CONCLUSIONS: Semi-ellipsoid attachment performed better efficacy on labiolingual inclination, and power ridge performed better efficacy on root control. However, a distal twist of maxillary incisors could be generated by the power ridge.


Asunto(s)
Análisis de Elementos Finitos , Incisivo , Maxilar , Técnicas de Movimiento Dental , Torque , Humanos , Técnicas de Movimiento Dental/métodos , Técnicas de Movimiento Dental/instrumentación , Ligamento Periodontal/fisiología , Análisis del Estrés Dental/métodos , Diseño de Aparato Ortodóncico , Aparatos Ortodóncicos Removibles
4.
Clin Oral Investig ; 27(7): 3863-3873, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37036513

RESUMEN

OBJECTIVES: The objectives of this retrospective clinical study were to evaluate the efficacy of clear aligners on upper-incisor torque control, with the expectation of providing guidance for clinics. MATERIALS AND METHODS: Pretreatment (T0) and posttreatment (T1) cone-beam computed tomography (CBCT) scans of 47 patients with a nonextraction treatment using clear aligners were obtained and 120 upper-incisors with torque ≥5° were selected. Voxel-based superimpositions were performed using Dolphin imaging software and achieved movements were then measured. Difference between achieved and predicted movement (DAPM) and the efficiency for upper-incisor torque were used to evaluate the torque control efficacy. RESULTS: The achieved torque movement with clear aligners was lower than predicted significantly, as the mean efficiency was 46.81±33.95%. Additionally, the achieved incisor movement of the crown and root differed significantly from the predicted movement, especially root movement. CONCLUSIONS: Clear aligners struggle to control upper-incisor torque, particularly root movement. In that case, overcorrection is necessary to prevent torque loss. CLINICAL RELEVANCE: Clear aligners remain a limitation on torque control and overcorrection should be considered.


Asunto(s)
Tomografía Computarizada de Haz Cónico , Incisivo , Aparatos Ortodóncicos Removibles , Torque , Incisivo/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada de Haz Cónico/métodos , Técnicas de Movimiento Dental
5.
J Craniofac Surg ; 34(2): 768-771, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36002926

RESUMEN

This study is intended to investigate oral exostoses of 5 sample populations, spanning over 6000 years, from the same region of Northern China, to determine the significance of sex and age on the development of oral exostoses during each time period. The samples analyzed were 306 dry jaws from human skeletons, which were excavated from 4 archeological sites: Banpo (6700-5600 y BP), Shaolingyuan (3000 y BP), Shanren (2200 y BP), and Chang'an (1000-1300 y BP), as well as the modern Xi'an district. The sex and the age of the samples at death were estimated. The degree of buccal exostosis (BE), torus mandibularis (TM), and torus palatinus (TP) and the TP shape were recorded. The results showed BEs in the Banpo and Chang'an regions, TMs in the Banpo region were more often diagnosed in males than in females. Conversely, females in Shaolingyuan showed a higher prevalence and severity of TM than that in males. The occurrence of BEs in the Shanren and Xi'an regions, TMs in the Banpo, Chang'an, and Xi'an regions, as well as TPs in the Banpo region significantly increased with age at death. In conclusion, sex differences and increasing trends with age in relation to oral exostoses were found in samples from Northern China during the past six millennia.


Asunto(s)
Exostosis , Enfermedades Maxilomandibulares , Humanos , Masculino , Femenino , Prevalencia , Exostosis/epidemiología , China
6.
Angew Chem Int Ed Engl ; 62(5): e202214814, 2023 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-36461785

RESUMEN

Efficient biosynthesis of microbial bioactive natural products (NPs) is beneficial for the survival of producers, while self-protection is necessary to avoid self-harm resulting from over-accumulation of NPs. The underlying mechanisms for the effective but tolerable production of bioactive NPs are not well understood. Herein, in the biosynthesis of two fungal polyketide mycotoxins aurovertin E (1) and asteltoxin, we show that the cyclases in the gene clusters promote the release of the polyketide backbone, and reveal that a signal peptide is crucial for their subcellular localization and full activity. Meanwhile, the fungus adopts enzymatic acetylation as the major detoxification pathway of 1. If intermediates are over-produced, the non-enzymatic shunt pathways work as salvage pathways to avoid excessive accumulation of the toxic metabolites for self-protection. These findings provided new insight into the interplay of efficient backbone release and multiple detoxification strategies for the production of fungal bioactive NPs.


Asunto(s)
Micotoxinas , Policétidos , Policétidos/metabolismo , Sintasas Poliquetidas/genética , Sintasas Poliquetidas/metabolismo , Procesamiento Proteico-Postraduccional , Familia de Multigenes
7.
Appl Opt ; 59(11): 3353-3359, 2020 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-32400445

RESUMEN

We present a practical wide-field optical design for a 60 m aperture submillimeter telescope, which is currently under conceptual design study in China. The telescope is specified to operate over a wavelength range of 0.65-3 mm and provide a wide field of view (FOV) of 1° in diameter. We designed an F/6 Ritchey Chrétien (RC) system with a quasi-planar tertiary corrector, which cancels all spherical, coma, and astigmatism aberrations. It also achieves a good balance among the mirror sizes, central obscuration, and focal-plane curvature. The problems of focal surface curvature and nontelecentricity are treated in the subfield instrumental design, which employs a simple silicon wedge prism to obtain flat and telecentric focal planes for each subfield instrument module. Our studies show that by such a design, more than ${{10}^5}$105 detector pixels can be efficiently and uniformly fed at the shortest wavelength band with Strehl ratios above 0.85 across the entire 1° FOV. Several practical issues related to the telescope optics are also discussed.

8.
Am J Pathol ; 187(5): 963-972, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28302495

RESUMEN

Recent studies indicate that neural EGFL-like 1 (Nell-1), a secretive extracellular matrix molecule, is involved in chondrogenic differentiation. Herein, we demonstrated that Nell-1 serves as a key downstream target of runt-related transcription factor 2 (Runx2), a central regulator of chondrogenesis. Unlike in osteoblast lineage cells where Nell-1 and Runx2 demonstrate mutual regulation, further studies in chondrocytes revealed that Runx2 tightly regulates the expression of Nell-1; however, Nell-1 does not alter the expression of Runx2. More important, Nell-1 administration partially restored Runx2 deficiency-induced impairment of chondrocyte differentiation and maturation in vitro, ex vivo, and in vivo. Mechanistically, although the expression of Nell-1 is highly reliant on Runx2, the prochondrogenic function of Nell-1 persisted in Runx2-/- scenarios. The biopotency of Nell-1 is independent of the nuclear import and DNA binding functions of Runx2 during chondrogenesis. Nell-1 is a key functional mediator of chondrogenesis, thus opening up new possibilities for the application of Nell-1 in cartilage regeneration.


Asunto(s)
Proteínas de Unión al Calcio/fisiología , Cartílago/fisiología , Condrogénesis/fisiología , Subunidad alfa 1 del Factor de Unión al Sitio Principal/fisiología , Glicoproteínas/fisiología , Animales , Diferenciación Celular/fisiología , Proliferación Celular/fisiología , Condrocitos/fisiología , Fémur/embriología , Fémur/crecimiento & desarrollo , Miembro Posterior/fisiología , Ratones Endogámicos C57BL , Regeneración
9.
Cells Tissues Organs ; 204(1): 25-37, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28478436

RESUMEN

Animal studies have reported on the benefits of ARB on bone mass. However, the underlying mechanism for angiotensin II (AngII)/AngII receptor blockade (ARB) in regulating bone mass remains elusive. Since high levels of plasma and urine cAMP are observed in osteoporotic and hypertensive patients, we hypothesized that cAMP may be an important molecule for the downstream events of the activation of AT receptors, members of the G-protein-coupled receptor family, in regulating bone turnover. In this study, micro-CT and X-ray analyses indicated that AngII decreased bone mass via biasing bone resorption over bone formation in osteoporotic mice. However, these adverse effects were blocked by olmesartan and PD123319. In vitro, AngII was shown to downregulate osteogenic differentiation and matrix mineralization, but to upregulate osteoclastic activity by mainly affecting osteoblasts producing osteoclastogenesis-associated key soluble factors, including M-CSF and RANKL. Similarly, ARB treatment exhibited antagonistic effects on AngII. In conclusion, osteoblasts are the directly targeted cells. ARB1 exhibits a greater capacity to increase bone mass than ARB2. The cAMP-dependent PKA pathway plays an important role in AngII/ARB on changing bone mass.


Asunto(s)
Angiotensina II/metabolismo , Antagonistas de Receptores de Angiotensina/metabolismo , Hipertensión/tratamiento farmacológico , Osteoporosis/tratamiento farmacológico , Receptores de Angiotensina/efectos de los fármacos , Animales , Femenino , Hipertensión/patología , Ratones , Ratones Endogámicos C57BL , Osteoporosis/patología
10.
Appl Environ Microbiol ; 82(6): 1898-1905, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26773081

RESUMEN

Daptomycin is a potent cyclic lipopeptide antibiotic. It is widely used against various Gram-positive bacterial pathogens. Historically, a poor understanding of the transcriptional regulation of daptomycin biosynthesis has limited the options for targeted genetic engineering toward titer improvement. Here, we isolated a TetR family transcriptional regulator, DepR1, from the industrial producer Streptomyces roseosporus SW0702 using a biotinylated dptE promoter (dptEp) as a probe. The direct interaction between DepR1 and dptEp then was confirmed by electrophoretic mobility shift assays and DNase I footprinting assays. The deletion of depR1 led to a reduction in dptEp activity and the cessation of daptomycin production. The ΔdepR1 mutant produced less red pigment and failed to sporulate on R5 medium. This suggests that DepR1 plays a positive role in the control of morphological differentiation. Moreover, DepR1 was positively autoregulated by directly binding to its own promoter. This might account for the positive feedback regulation of daptomycin production. Based on these positive effects, genetic engineering by overexpression of depR1 raised daptomycin production and shortened the fermentation period both in flask and in fermentor.


Asunto(s)
Antibacterianos/biosíntesis , Daptomicina/biosíntesis , Regulación Bacteriana de la Expresión Génica , Streptomyces/genética , Streptomyces/metabolismo , Factores de Transcripción/genética , Huella de ADN , ADN Bacteriano/metabolismo , Ensayo de Cambio de Movilidad Electroforética , Eliminación de Gen , Pigmentos Biológicos/biosíntesis , Unión Proteica , Esporas Bacterianas/crecimiento & desarrollo , Streptomyces/crecimiento & desarrollo , Transcripción Genética
11.
Stem Cells ; 33(3): 904-15, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25376942

RESUMEN

Neural epidermal growth factor-like (NEL)-like protein 1 (NELL-1) has been identified as an osteoinductive differentiation factor that promotes mesenchymal stem cell (MSC) osteogenic differentiation. In addition to full-length NELL-1, there are several NELL-1-related transcripts reported. We used rapid amplification of cDNA ends to recover potential cDNA of NELL-1 isoforms. A NELL-1 isoform with the N-terminal 240 amino acid (aa) residues truncated was identified. While full-length NELL-1 that contains 810 aa residues (NELL-1810 ) plays an important role in embryologic skeletal development, the N-terminal-truncated NELL-1 isoform (NELL-1570 ) was expressed postnatally. Similar to NELL-1810 , NELL-1570 induced MSC osteogenic differentiation. In addition, NELL-1570 significantly stimulated MSC proliferation in multiple MSC-like populations such as murine C3H10T1/2 MSC cell line, mouse primary MSCs, and perivascular stem cells, which is a type of stem cells proposed as the perivascular origin of MSCs. In contrast, NELL-1810 demonstrated only limited stimulation of MSC proliferation. Similar to NELL-1810 , NELL-1570 was found to be secreted from host cells. Both NELL-1570 expression lentiviral vector and column-purified recombinant protein NELL-1570 demonstrated almost identical effects in MSC proliferation and osteogenic differentiation, suggesting that NELL-1570 may function as a pro-osteogenic growth factor. In vivo, NELL-1570 induced significant calvarial defect regeneration accompanied by increased cell proliferation. Thus, NELL-1570 has the potential to be used for cell-based or hormone-based therapy of bone regeneration.


Asunto(s)
Proteínas de Unión al Calcio/genética , Glicoproteínas/genética , Células Madre Mesenquimatosas/citología , Proteínas del Tejido Nervioso/genética , Osteogénesis/fisiología , Animales , Proteínas de Unión al Calcio/biosíntesis , Proteínas de Unión al Calcio/metabolismo , Diferenciación Celular/fisiología , Línea Celular , Proliferación Celular/fisiología , Glicoproteínas/biosíntesis , Glicoproteínas/metabolismo , Células HEK293 , Humanos , Masculino , Células Madre Mesenquimatosas/metabolismo , Ratones , Ratones Endogámicos C3H , Proteínas del Tejido Nervioso/biosíntesis , Proteínas del Tejido Nervioso/metabolismo , Isoformas de Proteínas , Ratas , Ratas Sprague-Dawley
12.
Aust Orthod J ; 32(2): 148-154, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29509339

RESUMEN

BACKGROUND: A Class Il malocclusion is the most frequent sagittal skeletal disharmony presenting for orthodontic treatment. A transverse interarch discrepancy ITID) may be considered as a possible functional cause of a Class 11 relationship. OBJECTIVE: The purpose of the present study was to determine transverse interarch width dimensions before and after orthodontic therapy and their possible relationship with increased mandibular projection following treatment. METHODS: The sample included 40 adolescent patients who were divided into two groups, one possessing and one without a transverse discrepancy. Interarch width differences (including ICWD, IPWD, IMWD, IAWD) were measured before and after treatment, and Pogonion (Pog) to Nasion (NJ perpendicular was similarly measured in each group. RESULTS: The differences in arch and alveolar width dimensions between the two groups (including ICWD, IPWDI, IPWDII, IMWD, IAWD) before treatment were statistically significant (p < 0.05). A comparison of Pog to N perpendicular between the two groups showed that mandibular protrusion after treatment in the transverse discrepancy group was 2.6 ± 1.3 mm, while mandibular protrusion after treatment in the group without a transverse discrepancy was 0.6 ±0.3 mm. The statistical comparison showed that the differences were significant (p < 0.01). CONCLUSION: A transverse interarch discrepancy may have a functional relationship with mandible retrusion. If a transverse discrepancy is corrected via orthodontic treatment, the mandible may spontaneously protrude.


Asunto(s)
Maloclusión Clase II de Angle/terapia , Mandíbula/patología , Ortodoncia Correctiva/métodos , Adolescente , Cefalometría , Niño , Femenino , Humanos , Masculino , Ortodoncia Correctiva/instrumentación , Resultado del Tratamiento
13.
Cell Tissue Res ; 362(2): 399-405, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26149648

RESUMEN

We investigate whether the expression of the receptor activator of nuclear factor kappa-B ligand (RANKL) and osteoprotegerin (OPG) in human dental follicle cells (HDFCs) regulated by colony stimulating factor 1 (CSF-1), parathyroid hormone-related protein (PTHrP) and bone morphogenetic protein-2 (BMP-2) contributes to osteoclastogenesis. Adolescent human impacted third mandibular molars were used to separate HDFCs. These cells were incubated with PTHrP (10 ng/ml), CSF-1 (25 ng/ml), or BMP-2 (100 ng/ml) for 0.5, 1, 3, 6 and 12 h. The expression of OPG and RANKL was investigated by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). Two co-culture systems and tartrate-resistant acid phosphatase (TRAP) staining were used to examine osteoclast formation. Scanning electron microscopy was utilized for the resorption pit assay. RANKL and OPG were expressed innately in HDFCs. Exogenous PTHrP, CSF-1 and BMP-2 chronologically regulated the expression of RANKL and OPG in HDFCs. PTHrP and CSF-1 had similar regulative patterns leading to the up-regulated expression of RANKL and the down-regulated expression of OPG and opposite for BMP-2. The number of TRAP-positive peripheral blood mononuclear cells (PBMCs) slightly increased in contacted co-culture of HDFCs and PBMCs, whereas secreted OPG from HDFCs inhibited osteoclastogenesis in the transwell co-culture system. Contacted co-culture of HDFCs and PBMCs exhibited small and shallow resorption pits, whereas in the transwell co-culture system, secreted OPG from HDFCs reduced the resorption pits, reflecting the difference in osteoclast production. Collectively, we found a dual action of HDFCs in osteoclastogenesis; moreover, PTHrP, CSF-1 and BMP-2 might influence osteoclastogenesis by regulating the expression of RANKL and OPG in HDFCs.


Asunto(s)
Saco Dental/metabolismo , Leucocitos Mononucleares/metabolismo , Glicoproteínas de Membrana/metabolismo , Osteoclastos/metabolismo , Osteoprotegerina/metabolismo , Receptor Activador del Factor Nuclear kappa-B/metabolismo , Adolescente , Células Cultivadas , Técnicas de Cocultivo/métodos , Humanos
14.
Am J Orthod Dentofacial Orthop ; 147(6): 725-37, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26038077

RESUMEN

INTRODUCTION: The purpose of this study was to propose a protocol for safe bicortical placement of mini-implants by measuring the interradicular spaces of the maxillary teeth and the bone quality. METHODS: Cone-beam computed tomography data were obtained from 50 adults. Three-dimensional reconstructions and measurements were made with SimplantPro software (Materialise, Leuven, Belgium). For each interradicular site, the bone thicknesses and interradicular distances at the planes 1.5, 3, 6, and 9 mm above the cementoenamel junction were measured. Standard bone units were defined to evaluate the influences of bone density and the different placement patterns on the stability of the mini-implants. RESULTS: The safe interradicular sites in the maxilla for bicortical placement of 1.5-mm-diameter mini-implants were in all planes between the first and second premolars, and between the second premolar and the first molar. The safe palatal sites were between the first and second molars, and the safe labial sites of the 9-mm plane were between the central incisors, and between the lateral incisor and the canine. The safe buccal sites of the 6- and 9-mm planes were between the first and second molars, and the safe buccal sites of the 3-, 6-, and 9-mm planes were between the canine and the first premolar. Most bone thicknesses were from 8 to 12 mm. The optimal placement angle between the second premolar and the first molar was 58°. Bicortical placement could have more standard bone units than unicortical placement in the maxilla. CONCLUSIONS: Bicortical placement would be more stable in the maxilla. For the site between the molars, special care should be taken at a plane higher than 6 mm to prevent maxillary sinus penetration. The most favorable interradicular area in the maxilla was between the second premolar and the first molar.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Maxilar/diagnóstico por imagen , Métodos de Anclaje en Ortodoncia/instrumentación , Adolescente , Adulto , Proceso Alveolar/diagnóstico por imagen , Diente Premolar/diagnóstico por imagen , Densidad Ósea/fisiología , Diente Canino/diagnóstico por imagen , Arco Dental/diagnóstico por imagen , Implantes Dentales , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagenología Tridimensional/métodos , Incisivo/diagnóstico por imagen , Masculino , Seno Maxilar/diagnóstico por imagen , Miniaturización , Diente Molar/diagnóstico por imagen , Métodos de Anclaje en Ortodoncia/métodos , Cuello del Diente/diagnóstico por imagen , Raíz del Diente/diagnóstico por imagen , Adulto Joven
15.
J Neurosci Methods ; : 110197, 2024 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-38878976

RESUMEN

BACKGROUND: Trigeminal ganglion (TG) plays an important role in the process of orthodontic pain. It's necessary to design an accurate, precise and minimally invasive trigeminal ganglion injection guide plate to study TG. METHODS: Micro-CT was used to obtain the Dicom format data, and three-dimensional (3D) software (mimics and magics23.03) was used to reconstruct 3D head models. Design and modifications of the TG injection guide plate were performed in Magic 23.03 software, and the guide plate was produced by a 3D stereolithography printer. X-ray, micro-CT, Evans blue, and virus transduction were used to demonstrate the accuracy of the guide-assisted injection. Pain levels were evaluated after using the injection guide by a bite force test and Von Frey test. RESULTS: X-ray and micro-CT tests confirmed that the injection needle reached the bilateral trigeminal ganglia fossa. The Evans blue test and virus transduction proved that the injected drug could be accurately injected into the bilateral trigeminal ganglion and the lentivirus could be successfully transfected. The percentage of accurate injection was 10/10 (bilateral trigeminal ganglia). Orofacial pain induced by the trigeminal ganglion injection was mild and returned to baseline within seven days. CONCLUSION: The injection guide described in this study is viable and reliable for the delivery of drugs and virus transduction into the trigeminal ganglia.

16.
J Inflamm Res ; 17: 2639-2653, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38707958

RESUMEN

Osteoblasts (OBs), which are a crucial type of bone cells, derive from bone marrow mesenchymal stem cells (MSCs). Accumulating evidence suggests inflammatory cytokines can inhibit the differentiation and proliferation of OBs, as well as interfere with their ability to synthesize bone matrix, under inflammatory conditions. NLRP3 inflammasome is closely associated with cellular pyroptosis, which can lead to excessive release of pro-inflammatory cytokines, causing tissue damage and inflammatory responses, however, the comprehensive roles of NLRP3 inflammasome in OBs and their differentiation have not been fully elucidated, making targeting NLRP3 inflammasome approaches to treat diseases related to OBs uncertain. In this review, we provide a summary of NLRP3 inflammasome activation and its impact on OBs. We highlight the significant roles of NLRP3 inflammasome in regulating OBs differentiation and function. Furthermore, current available strategies to affect OBs function and osteogenic differentiation targeting NLRP3 inflammasome are listed and analyzed. Finally, through the prospective discussion, we seek to provide novel insights into the crucial role of NLRP3 inflammasome in diseases related to OBs and offer valuable information for devising treatment strategies.

17.
PeerJ Comput Sci ; 10: e1994, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38660190

RESUMEN

Cone beam computed tomography (CBCT) is widely employed in modern dentistry, and tooth segmentation constitutes an integral part of the digital workflow based on these imaging data. Previous methodologies rely heavily on manual segmentation and are time-consuming and labor-intensive in clinical practice. Recently, with advancements in computer vision technology, scholars have conducted in-depth research, proposing various fast and accurate tooth segmentation methods. In this review, we review 55 articles in this field and discuss the effectiveness, advantages, and disadvantages of each approach. In addition to simple classification and discussion, this review aims to reveal how tooth segmentation methods can be improved by the application and refinement of existing image segmentation algorithms to solve problems such as irregular morphology and fuzzy boundaries of teeth. It is assumed that with the optimization of these methods, manual operation will be reduced, and greater accuracy and robustness in tooth segmentation will be achieved. Finally, we highlight the challenges that still exist in this field and provide prospects for future directions.

18.
J Cosmet Dermatol ; 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38726847

RESUMEN

BACKGROUND: Botulinum neurotoxin injections are the most frequently performed cosmetic procedures, but conventional blind injection for glabellar wrinkles remains to have some limitations. AIMS: We intend to directly inject botulinum neurotoxin into the glabella complex guided by real time ultrasound. We aim to propose a more efficient and safer botulinum neurotoxin injection strategy for glabellar wrinkles. METHODS: A total of 40 subjects with moderate to severe glabellar lines were enrolled in this study to receive botulinum neurotoxin injection, either through ultrasound-guided real time injection or conventional blind injection. Facial Wrinkle Scale (ranging from 0 = none to 3 = severe) and inter-brow distance (from 3D scanned face images) were used to evaluate the glabellar wrinkles improvement. Paired t test and two-sample t test were performed to analyze the within-group and between-group differences. RESULTS: The wrinkle score reduction was significant (p < 0.0001) immediately after the injection in ultrasound-guided injection group, but not in blind injection group (p = 0.163). Ultrasound-guided injection also showed a higher performance of wrinkle score reduction and more effective inter-brow distance increase over blind injection at Day 0 (p < 0.0001), Day 1 (p < 0.0001), Day 21 (p < 0.01) and Day 35 (p < 0.01) after initial treatment. CONCLUSIONS: The results of the study confirmed that botulinum neurotoxin injection for glabellar wrinkles under ultrasound guidance achieves quicker onset of action and better final outcomes compared to conventional blind injection.

19.
Arch Oral Biol ; 163: 105963, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38608563

RESUMEN

OBJECTIVES: Orthodontic tooth movement is a mechanobiological reaction induced by appropriate forces, including bone remodeling. The mechanosensitive Piezo channels have been shown to contribute to bone remodeling. However, information about the pathways through which Piezo channels affects osteoblasts remains limited. Thus, we aimed to investigate the influence of Piezo1 on the osteogenic and osteoclast factors in osteoblasts under mechanical load. MATERIALS AND METHODS: Cyclic stretch (CS) experiments on MC3T3-E1 were conducted using a BioDynamic mechanical stretching device. The Piezo1 channel blocker GsMTx4 and the Piezo1 channel agonist Yoda1 were used 12 h before the application of CS. MC3T3-E1 cells were then subjected to 15% CS, and the expression of Piezo1, Piezo2, BMP-2, OCN, Runx2, RANKL, p-p65/p65, and ALP was measured using quantitative real-time polymerase chain reaction, western blot, alkaline phosphatase staining, and immunofluorescence staining. RESULTS: CS of 15% induced the highest expression of Piezo channel and osteoblast factors. Yoda1 significantly increased the CS-upregulated expression of Piezo1 and ALP activity but not Piezo2 and RANKL. GsMTx4 downregulated the CS-upregulated expression of Piezo1, Piezo2, Runx2, OCN, p-65/65, and ALP activity but could not completely reduce CS-upregulated BMP-2. CONCLUSIONS: The appropriate force is more suitable for promoting osteogenic differentiation in MC3T3-E1. The Piezo1 channel participates in osteogenic differentiation of osteoblasts through its influence on the expression of osteogenic factors like BMP-2, Runx2, and OCN and is involved in regulating osteoclasts by influencing phosphorylated p65. These results provide a foundation for further exploration of osteoblast function in orthodontic tooth movement.


Asunto(s)
Proteína Morfogenética Ósea 2 , Subunidad alfa 1 del Factor de Unión al Sitio Principal , Canales Iónicos , Osteoblastos , Osteogénesis , Osteoblastos/metabolismo , Canales Iónicos/metabolismo , Animales , Ratones , Proteína Morfogenética Ósea 2/metabolismo , Osteogénesis/fisiología , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Osteoclastos/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Ligando RANK/metabolismo , Western Blotting , Estrés Mecánico , Diferenciación Celular , Osteocalcina/metabolismo , Fosfatasa Alcalina/metabolismo , Oligopéptidos/farmacología , Técnicas de Movimiento Dental , Mecanotransducción Celular/fisiología , Línea Celular , Remodelación Ósea/fisiología , Pirazinas , Venenos de Araña , Tiadiazoles , Péptidos y Proteínas de Señalización Intercelular
20.
Adv Mater ; 36(1): e2307987, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37956304

RESUMEN

Wide-bandgap (WBG) perovskite solar cells have attracted considerable interest for their potential applications in tandem solar cells. However, the predominant obstacles impeding their widespread adoption are substantial open-circuit voltage (VOC ) deficit and severe photo-induced halide segregation. To tackle these challenges, a crystal orientation regulation strategy by introducing dodecyl-benzene-sulfonic-acid as an additive in perovskite precursors is proposed. This method significantly promotes the desired crystal orientation, passivates defects, and mitigates photo-induced halide phase segregation in perovskite films, leading to substantially reduced nonradiative recombination, minimized VOC deficits, and enhanced operational stability of the devices. The resulting 1.66 eV bandgap methylamine-free perovskite solar cells achieve a remarkable power conversion efficiency (PCE) of 22.40% (certified at 21.97%), with the smallest VOC deficit recorded at 0.39 V. Furthermore, the fabricated semitransparent WBG devices exhibit a competitive PCE of 20.13%. Consequently, four-terminal tandem cells comprising WBG perovskite top cells and 1.25 eV bandgap perovskite bottom cells showcase an impressive PCE of 28.06% (stabilized 27.92%), demonstrating great potential for efficient multijunction tandem solar cell applications.

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