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1.
Integr Comp Biol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637301

RESUMO

Metameric somites are a novel character of chordates with unclear evolutionary origins. In the early branching chordate amphioxus, anterior somites are derived from the paraxial mesodermal cells that bud off the archenteron (i.e., enterocoely) at the end of gastrulation. Development of the anterior somites requires FGF signaling, and distinct somite compartments express orthologs of vertebrate non-axial mesodermal markers. Thus, it has been proposed that the amphioxus anterior somites are homologous to the vertebrate head mesoderm, paraxial mesoderm and lateral plate mesoderm. To trace the evolutionary origin of somites, it is essential to study the chordates' closest sister group, Ambulacraria, which includes hemichordates and echinoderms. The anterior coeloms of hemichordate and sea urchin embryos (respectively called protocoel and coelomic pouches) are also formed by enterocoely and require FGF signals for specification and/or differentiation. In this study, we applied RNA-seq to comprehensively screen for regulatory genes associated with the mesoderm-derived protocoel of the hemichordate Ptychodera flava. We also used a candidate gene approach to identify P. flava orthologs of chordate somite markers. In situ hybridization results showed that many of these candidate genes are expressed in distinct or overlapping regions of the protocoel, which indicates that molecular compartments exist in the hemichordate anterior coelom. Given that the hemichordate protocoel and amphioxus anterior somites share a similar ontogenic process (enterocoely), induction signal (FGF), and characteristic expression of orthologous genes, we propose that these two anterior coeloms are indeed homologous. In the lineage leading to the emergence of chordates, somites likely evolved from enterocoelic, FGF-dependent, and molecularly compartmentalized anterior coeloms of the deuterostome last common ancestor.

2.
J Dent Sci ; 19(1): 438-447, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303797

RESUMO

Background/purpose: Dysregulation of receptor tyrosine kinases is implicated in cancer development. This study aimed to investigate the nuclear translocation of Axl, a membrane protein and receptor tyrosine kinase in cancer malignancy. Materials and methods: We examined Axl's entry into the cell nucleus and validated it with the nuclear export inhibitor leptomycin. Transfection experiments with mutated nuclear localization signals were conducted to assess the impact of reduced nuclear Axl levels on cancer cell malignancy. Additionally, we evaluated the effects of decreased nuclear Axl on sensitivity to radiation and cisplatin, a chemotherapeutic drug. Results: In the present study, we observed nuclear translocation of Axl in cancer cells. Reducing nuclear Axl levels led to a decrease in cancer cell malignancy. This nuclear translocation was further validated using a nuclear export inhibitor, leptomycin. Additionally, transfection experiments with mutated nuclear localization signals confirmed the functional significance of Axl's nuclear localization. Notably, decreased nuclear Axl levels also increased the sensitivity of cancer cells to radiation and cisplatin treatment. Conclusion: This study suggests that Axl's nuclear translocation plays a significant role in cancer malignancy. Targeting Axl's nuclear localization could offer a potential strategy to inhibit cancer progression and improve the efficacy of radiation and chemotherapy treatments.

3.
J Dent Sci ; 19(1): 428-437, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38303867

RESUMO

Background/purpose: Oral cancer is a prevalent malignancy affecting men globally. This study aimed to investigate the regulatory role of miR-34a in oral cancer cells through the Axl/Akt/glycogen synthase kinase-3ß (GSK-3ß) pathway and its impact on cellular malignancy. Materials and methods: We examined the effects of miR-34a overexpression on the malignancy of oral cancer cells. Multiple oral cancer cell lines were assessed to determine the correlation between endogenous miR-34a and Axl levels. Transfection experiments with miR-34a were conducted to analyze its influence on Axl mRNA and protein expression. Luciferase reporter assays were performed to investigate miR-34a's modulation of Axl gene transcription. Manipulation of miR-34a expression was utilized to demonstrate its regulatory effects on oral cancer cells through the Axl/Akt/GSK-3ß pathway. Results: Overexpression of miR-34a significantly suppressed the malignancy of oral cancer cells. We observed an inverse correlation between endogenous miR-34a and Axl levels across multiple oral cancer cell lines. Transfection of miR-34a resulted in decreased Axl mRNA and protein expression, and luciferase reporter assays confirmed miR-34a-mediated modulation of Axl gene transcription. The study revealed regulatory effects of miR-34a on oral cancer cells through the Axl/Akt/GSK-3ß pathway, leading to alterations in downstream target genes involved in cellular proliferation and tumorigenesis. Conclusion: Our findings highlight the significance of the miR-34a/Axl/Akt/GSK-3ß signaling axis in modulating the malignancy of oral cancer cells. Targeting miR-34a may hold therapeutic potential in oral cancer treatment, as manipulating its expression can attenuate the aggressive behavior of oral cancer cells via the Axl/Akt/GSK-3ß pathway.

4.
Sci Adv ; 9(49): eadk1597, 2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38064557

RESUMO

Silicon CMOS-based computing-in-memory encounters design and power challenges, especially in logic-in-memory scenarios requiring nonvolatility and reconfigurability. Here, we report a universal design for nonvolatile reconfigurable devices featuring a 2D/3D heterointegrated configuration. By leveraging the photo-controlled charge trapping/detrapping process and the partially top-gated energy band landscape, the van der Waals heterostacking achieves polarity storage and logic reconfigurable characteristics, respectively. Precise polarity tunability, logic nonvolatility, robustness against high temperature (at 85°C), and near-ideal subthreshold swing (80 mV dec-1) can be done. A comprehensive investigation of dynamic charge fluctuations provides a holistic understanding of the origins of nonvolatile reconfigurability (a trap level of 1013 cm-2 eV-1). Furthermore, we cascade such nonvolatile reconfigurable units into a monolithic circuit layer to demonstrate logic-in-memory computing possibilities, such as high-gain (65 at Vdd = 0.5 V) logic gates. This work provides an innovative 3D heterointegration prototype for future computing-in-memory hardware.

5.
Mol Biol Evol ; 40(11)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37850912

RESUMO

A series of "molecular domestication" events are thought to have converted an invertebrate RAG-like (RAGL) transposase into the RAG1-RAG2 (RAG) recombinase, a critical enzyme for adaptive immunity in jawed vertebrates. The timing and order of these events are not well understood, in part because of a dearth of information regarding the invertebrate RAGL-A transposon family. In contrast to the abundant and divergent RAGL-B transposon family, RAGL-A most closely resembles RAG and is represented by a single orphan RAG1-like (RAG1L) gene in the genome of the hemichordate Ptychodera flava (PflRAG1L-A). Here, we provide evidence for the existence of complete RAGL-A transposons in the genomes of P. flava and several echinoderms. The predicted RAG1L-A and RAG2L-A proteins encoded by these transposons intermingle sequence features of jawed vertebrate RAG and RAGL-B transposases, leading to a prediction of DNA binding, catalytic, and transposition activities that are a hybrid of RAG and RAGL-B. Similarly, the terminal inverted repeats (TIRs) of the RAGL-A transposons combine features of both RAGL-B transposon TIRs and RAG recombination signal sequences. Unlike all previously described RAG2L proteins, RAG2L-A proteins contain an acidic hinge region, which we demonstrate is capable of efficiently inhibiting RAG-mediated transposition. Our findings provide evidence for a critical intermediate in RAG evolution and argue that certain adaptations thought to be specific to jawed vertebrates (e.g. the RAG2 acidic hinge) actually arose in invertebrates, thereby focusing attention on other adaptations as the pivotal steps in the completion of RAG domestication in jawed vertebrates.


Assuntos
Elementos de DNA Transponíveis , Proteínas de Homeodomínio , Animais , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Vertebrados/genética , Vertebrados/metabolismo , Imunidade Adaptativa/genética
6.
bioRxiv ; 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37645967

RESUMO

A series of "molecular domestication" events are thought to have converted an invertebrate RAG-like (RAGL) transposase into the RAG1-RAG2 (RAG) recombinase, a critical enzyme for adaptive immunity in jawed vertebrates. The timing and order of these events is not well understood, in part because of a dearth of information regarding the invertebrate RAGL-A transposon family. In contrast to the abundant and divergent RAGL-B transposon family, RAGL-A most closely resembles RAG and is represented by a single orphan RAG1-like (RAG1L) gene in the genome of the hemichordate Ptychodera flava (PflRAG1L-A). Here, we provide evidence for the existence of complete RAGL-A transposons in the genomes of P. flava and several echinoderms. The predicted RAG1L-A and RAG2L-A proteins encoded by these transposons intermingle sequence features of jawed vertebrate RAG and RAGL-B transposases, leading to a prediction of DNA binding, catalytic, and transposition activities that are a hybrid of RAG and RAGL-B. Similarly, the terminal inverted repeats (TIRs) of the RAGL-A transposons combine features of both RAGL-B transposon TIRs and RAG recombination signal sequences. Unlike all previously described RAG2L proteins, PflRAG2L-A and echinoderm RAG2L-A contain an acidic hinge region, which we demonstrate is capable of efficiently inhibiting RAG-mediated transposition. Our findings provide evidence for a critical intermediate in RAG evolution and argue that certain adaptations thought to be specific to jawed vertebrates (e.g., the RAG2 acidic hinge) actually arose in invertebrates, thereby focusing attention on other adaptations as the pivotal steps in the completion of RAG domestication in jawed vertebrates.

7.
J Pers Med ; 13(3)2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36983675

RESUMO

Mucopolysaccharidosis (MPS) is a hereditary disorder arising from lysosomal enzymes deficiency, with glycosaminoglycans (GAGs) storage in connective tissues and bones, which may compromise the airway. This retrospective study evaluated patients with MPS type IVA with airway obstruction detected via endoscopy and imaging modalities and the effects of surgical interventions based on symptoms. The data of 15 MPS type IVA patients (10 males, 5 females, mean age 17.8 years) were reviewed in detail. Fiberoptic bronchoscopy (FB) was used to distinguish adenotonsillar hypertrophy, prolapsed soft palate, secondary laryngomalacia, vocal cord granulation, cricoid thickness, tracheal stenosis, shape of tracheal lumen, nodular deposition, tracheal kinking, tracheomalacia with rigid tracheal wall, and bronchial collapse. Computed tomography (CT) helped to measure the deformed sternal angle, the cross-sectional area of the trachea, and its narrowest/widest ratio (NW ratio), while angiography with 3D reconstruction delineated tracheal torsion, kinking, or framework damage and external vascular compression of the trachea. The NW ratio correlated negatively with age (p < 0.01), showing that airway obstruction progressed gradually. Various types of airway surgery were performed to correct the respiratory dysfunction. MPS type IVA challenges the management of multifactorial airway obstruction. Preoperative airway evaluation with both FB and CT is strongly suggested to assess both intraluminal and extraluminal factors causing airway obstruction.

8.
ACS Appl Mater Interfaces ; 14(36): 41156-41164, 2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36037311

RESUMO

Contact engineering of two-dimensional semiconductors is a central issue for performance improvement of micro-/nanodevices based on these materials. Unfortunately, the various methods proposed to improve the Schottky barrier height normally require the use of high temperatures, chemical dopants, or complex processes. This work demonstrates that diffused electron beam energy (DEBE) treatment can simultaneously reduce the Schottky barrier height and enable the direct writing of electrical circuitry on van der Waals semiconductors. The electron beam energy projected into the region outside the electrode diffuses into the main channel, producing selective-area n-type doping in a layered MoTe2 (or MoS2) field-effect transistor. As a result, the Schottky barrier height at the interface between the electrode and the DEBE-treated MoTe2 channel is as low as 12 meV. Additionally, because selective-area doping is possible, DEBE can allow the formation of both n- and p-type doped channels within the same atomic plane, which enables the creation of a nonvolatile and homogeneous MoTe2 p-n rectifier with an ideality factor of 1.1 and a rectification ratio of 1.3 × 103. These results indicate that the DEBE method is a simple, efficient, mask-free, and chemical dopant-free approach to selective-area doping for the development of van der Waals electronics with excellent device performances.

9.
Adv Sci (Weinh) ; 9(24): e2106016, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35831244

RESUMO

Van der Waals (vdW) heterostructures-in which layered materials are purposely selected to assemble with each other-allow unusual properties and different phenomena to be combined and multifunctional electronics to be created, opening a new chapter for the spread of internet-of-things applications. Here, an O2 -ultrasensitive MoTe2 material and an O2 -insensitive SnS2 material are integrated to form a vdW heterostructure, allowing the realization of charge-polarity control for multioperation-mode transistors through a simple and effective rapid thermal annealing strategy under dry-air and vacuum conditions. The charge-polarity control (i.e., doping and de-doping processes), which arises owing to the interaction between O2 adsorption/desorption and tellurium defects at the MoTe2 surface, means that the MoTe2 /SnS2 heterostructure transistors can reversibly change between unipolar, ambipolar, and anti-ambipolar transfer characteristics. Based on the dynamic control of the charge-polarity properties, an inverter, output polarity controllable amplifier, p-n diode, and ternary-state logics (NMIN and NMAX gates) are demonstrated, which inspire the development of reversibly multifunctional devices and indicates the potential of 2D materials.

10.
J Dent Sci ; 17(2): 718-724, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35756756

RESUMO

Background/purpose: Oral cancer has been recognized as one of the most common malignancies worldwide and ranks the fifth leading cause of cancer death in Taiwan. A variety of studies have demonstrated that microRNAs are involved in the regulation of the hallmarks of oral carcinogenesis. Nevertheless, the effect of miR-1266-5p on the tumorigenesis of oral cancer has not been investigated, and not to mention, its functional role in oral cancer. Materials and methods: The upregulation of miR-1266-5p in SASVO3 and SASM5 cells was identified by RNA-Seq and examined by qRT-PCR analysis. The phenotypic assays including proliferation activity, migration capacity, invasion, wound healing, and colony-forming abilities were conducted in oral cancer cells after knockdown of miR-1266-5p. Luciferase reporter and western blotting were used to validate DAB2IP was a direct target of miR-1266-5p in oral cancer. Results: We identified that miR-1266-5p was significantly overexpressed in highly tumorigenic SASVO3 cells and metastatic SASM5 cells. qRT-PCR revealed that miR-1266 significantly increased upregulated in oral cancer and lymph node metastatic tissues compared to normal counterparts We found that downregulation of miR-1266-5p inhibited the proliferation and clonogenicity capacities of SASVO3 cells. Knockdown of miR-1266-5p also inhibited migration/invasion and self-renewal abilities in SASM5 cells. Moreover, we validated miR-1266-5p directly bound to the 3'UTR of DAB2IP in oral cancer cells. We found that DAB2IP knockdown reversed the inhibitory effects of self-renewal and migration mediated by silencing of miR-1266-5p. Conclusion: miR-1266 functions as a biomarker in oral cancer patients, and downregulation of miR-1266 may ameliorate the oncogenic and metastasis potential of oral cancer by targeting DAB2IP.

11.
Proc Natl Acad Sci U S A ; 119(11): e2114802119, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35263228

RESUMO

SignificanceIn this manuscript, we address an essential question in developmental and evolutionary biology: How have changes in gene regulatory networks contributed to the invertebrate-to-vertebrate transition? To address this issue, we perturbed four signaling pathways critical for body plan formation in the cephalochordate amphioxus and in zebrafish and compared the effects of such perturbations on gene expression and gene regulation in both species. Our data reveal that many developmental genes have gained response to these signaling pathways in the vertebrate lineage. Moreover, we show that the interconnectivity between these pathways is much higher in zebrafish than in amphioxus. We conclude that this increased signaling pathway complexity likely contributed to vertebrate morphological novelties during evolution.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Anfioxos , Peixe-Zebra , Animais , Evolução Biológica , Gastrulação/genética , Anfioxos/embriologia , Anfioxos/genética , Peixe-Zebra/embriologia , Peixe-Zebra/genética
12.
Bone Joint Res ; 11(2): 121-133, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35188421

RESUMO

AIMS: The decrease in the number of satellite cells (SCs), contributing to myofibre formation and reconstitution, and their proliferative capacity, leads to muscle loss, a condition known as sarcopenia. Resistance training can prevent muscle loss; however, the underlying mechanisms of resistance training effects on SCs are not well understood. We therefore conducted a comprehensive transcriptome analysis of SCs in a mouse model. METHODS: We compared the differentially expressed genes of SCs in young mice (eight weeks old), middle-aged (48-week-old) mice with resistance training intervention (MID+ T), and mice without exercise (MID) using next-generation sequencing and bioinformatics. RESULTS: After the bioinformatic analysis, the PI3K-Akt signalling pathway and the regulation of actin cytoskeleton in particular were highlighted among the top ten pathways with the most differentially expressed genes involved in the young/MID and MID+ T/MID groups. The expression of Gng5, Atf2, and Rtor in the PI3K-Akt signalling pathway was higher in the young and MID+ T groups compared with the MID group. Similarly, Limk1, Arhgef12, and Araf in the regulation of the actin cytoskeleton pathway had a similar bias. Moreover, the protein expression profiles of Atf2, Rptor, and Ccnd3 in each group were paralleled with the results of NGS. CONCLUSION: Our results revealed that age-induced muscle loss might result from age-influenced genes that contribute to muscle development in SCs. After resistance training, age-impaired genes were reactivated, and age-induced genes were depressed. The change fold in these genes in the young/MID mice resembled those in the MID + T/MID group, suggesting that resistance training can rejuvenate the self-renewing ability of SCs by recovering age-influenced genes to prevent sarcopenia. Cite this article: Bone Joint Res 2022;11(2):121-133.

13.
Int J Pediatr Otorhinolaryngol ; 152: 110989, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34861553

RESUMO

OBJECTIVE: Tracheostomy in children is a surgical procedure with considerable morbidity and mortality. However, there is still a lack of population-based survey in pediatric tracheostomy. This study analyses population-based data in pediatric tracheostomy among different ages in Taiwan. METHODS: This study used National Health Insurance Research Database in Taiwan. All children (aged <18 years) who underwent tracheostomy during 1997-2016 were identified. We retrieved data regarding baseline characteristics, perioperative care, and mortality associated with pediatric tracheostomy, and compared differences in variables between different age groups. RESULTS: We observed that 2300 children received tracheostomy (mean age, 8.7 years; 64% boys). Regarding the age group distribution of the patients, 585 (25.4%) were infants (<1 year), 227 (9.9%) were toddlers (1-3 years), 175 (7.6%) were preschool-aged children (3-6 years), 317 (13.8%) were school-aged children (6-12 years), and 996 (43.3%) were adolescents (12-18 years). Surgical indications included pulmonary disorders (64.9%), neurological disorders (38.4%), trauma (32.3%), head injury (25.2%), and congenital anomalies (21.5%). Of these patients, 94.9% required intensive care unit (ICU) care, with the mean length of ICU stay being 63.8 days. The mean length of hospital stay was 74.5 days. The overall mortality at the last follow-up was 43.96% (1011/2300), and the tracheostomy related mortality at the last follow-up was 1.43% (33/2300). Compared with adolescents, infants more commonly underwent tracheostomy in the northern area (66.7% vs 37.2%, P < .001), more commonly received tracheostomy indicated by congenital anomalies (53.7 vs 4.6%, P < .001), had longer ICU stays, had longer hospital stays (100.7 vs 57.5 days, P < .001), and had a higher 5-year mortality rate (42.4 vs 29.6%, P < .001). Multivariable logistic and Cox regression models revealed that young age was associated with an increased risk of prolonged hospital stay and long-term mortality, respectively. CONCLUSIONS: This study elaborates the epidemiology of pediatric tracheostomy in different age groups.


Assuntos
Traqueostomia , Traqueotomia , Adolescente , Criança , Pré-Escolar , Feminino , Mortalidade Hospitalar , Humanos , Lactente , Unidades de Terapia Intensiva , Tempo de Internação , Masculino , Programas Nacionais de Saúde , Respiração Artificial , Estudos Retrospectivos , Taiwan/epidemiologia
14.
PLoS Genet ; 17(12): e1009969, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34962934

RESUMO

Teleosts live in aquatic habitats, where they encounter ionic and acid-base fluctuations as well as infectious pathogens. To protect from these external challenges, the teleost epidermis is composed of living cells, including keratinocytes and ionocytes that maintain body fluid ionic homeostasis, and mucous cells that secret mucus. While ionocyte progenitors are known to be specified by Delta-Notch-mediated lateral inhibition during late gastrulation and early segmentation, it remains unclear how epidermal mucous cells (EMCs) are differentiated and maintained. Here, we show that Delta/Jagged-mediated activation of Notch signaling induces the differentiation of agr2-positive (agr2+) EMCs in zebrafish embryos during segmentation. We demonstrated that agr2+ EMCs contain cytoplasmic secretory granules and express muc5.1 and muc5.2. Reductions in agr2+ EMC number were observed in mib mutants and notch3 MOs-injected notch1a mutants, while increases in agr2+ cell number were detected in notch1a- and X-Su(H)/ANK-overexpressing embryos. Treatment with γ-secretase inhibitors further revealed that Notch signaling is required during bud to 15 hpf for the differentiation of agr2+ EMCs. Increased agr2+ EMC numbers were also observed in jag1a-, jag1b-, jag2a- and dlc-overexpressing, but not jag2b-overexpressing embryos. Meanwhile, reductions in agr2+ EMC numbers were detected in jag1a morphants, jag1b mutants, jag2a mutants and dlc morphants, but not jag2b mutants. Reduced numbers of pvalb8-positive epidermal cells were also observed in mib or jag2a mutants and jag1a or jag1b morphants, while increased pvalb8-positive epidermal cell numbers were detected in notch1a-overexpressing, but not dlc-overexpressing embryos. BrdU labeling further revealed that the agr2+ EMC population is maintained by proliferation. Cell lineage experiments showed that agr2+ EMCs are derived from the same ectodermal precursors as keratinocytes or ionocytes. Together, our results indicate that specification of agr2+ EMCs in zebrafish embryos is induced by DeltaC/Jagged-dependent activation of Notch1a/3 signaling, and the cell population is maintained by proliferation.


Assuntos
Desenvolvimento Embrionário/genética , Proteínas de Homeodomínio/genética , Proteína Jagged-1/genética , Proteína Jagged-2/genética , Proteínas do Tecido Nervoso/genética , Receptor Notch1/genética , Proteínas de Peixe-Zebra/genética , Animais , Proteínas de Ligação ao Cálcio/genética , Diferenciação Celular/genética , Ectoderma/crescimento & desenvolvimento , Epiderme/crescimento & desenvolvimento , Queratinócitos/citologia , Queratinócitos/metabolismo , Muco/metabolismo , Proteínas Mutantes/genética , Receptores Notch/genética , Transdução de Sinais/genética , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento
16.
PLoS Genet ; 16(12): e1009294, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33382716

RESUMO

Studies in various animals have shown that asymmetrically localized maternal transcripts play important roles in axial patterning and cell fate specification in early embryos. However, comprehensive analyses of the maternal transcriptomes with spatial information are scarce and limited to a handful of model organisms. In cephalochordates (amphioxus), an early branching chordate group, maternal transcripts of germline determinants form a compact granule that is inherited by a single blastomere during cleavage stages. Further blastomere separation experiments suggest that other transcripts associated with the granule are likely responsible for organizing the posterior structure in amphioxus; however, the identities of these determinants remain unknown. In this study, we used high-throughput RNA sequencing of separated blastomeres to examine asymmetrically localized transcripts in two-cell and eight-cell stage embryos of the amphioxus Branchiostoma floridae. We identified 111 and 391 differentially enriched transcripts at the 2-cell stage and the 8-cell stage, respectively, and used in situ hybridization to validate the spatial distribution patterns for a subset of these transcripts. The identified transcripts could be categorized into two major groups: (1) vegetal tier/germ granule-enriched and (2) animal tier/anterior-enriched transcripts. Using zebrafish as a surrogate model system, we showed that overexpression of one animal tier/anterior-localized amphioxus transcript, zfp665, causes a dorsalization/anteriorization phenotype in zebrafish embryos by downregulating the expression of the ventral gene, eve1, suggesting a potential function of zfp665 in early axial patterning. Our results provide a global transcriptomic blueprint for early-stage amphioxus embryos. This dataset represents a rich platform to guide future characterization of molecular players in early amphioxus development and to elucidate conservation and divergence of developmental programs during chordate evolution.


Assuntos
Blastômeros/metabolismo , Anfioxos/genética , Herança Materna , Transcriptoma , Animais , Regulação da Expressão Gênica no Desenvolvimento , Anfioxos/embriologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Peixe-Zebra
17.
ACS Appl Mater Interfaces ; 12(38): 42918-42924, 2020 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-32864950

RESUMO

Flexible manipulation of the carrier transport behaviors in two-dimensional materials determines their values of practical application in logic circuits. Here, we demonstrated the carrier-type manipulation in field-effect transistors (FETs) containing α-phase molybdenum ditelluride (MoTe2) by a rapid thermal annealing (RTA) process in dry air for hole-dominated and electron-beam (EB) treatment for electron-dominated FETs. EB treatment induced a distinct shift of the transfer curve by around 135 V compared with that of the FET-processed RTA treatment, indicating that the carrier density of the EB-treated FET was enhanced by about 1 order of magnitude. X-ray photoelectron spectroscopy analysis revealed that the atomic ratio of Te decreased from 66.4 to 60.8% in the MoTe2 channel after EB treatment. The Fermi level is pinned near the new energy level resulting from the Te vacancies produced by the EB process, leading to the electron-dominant effect of the MoTe2 FET. The electron-dominated MoTe2 FET showed excellent stability for more than 700 days. Thus, we not only realized the reversible modulation of carrier-type in layered MoTe2 FETs but also demonstrated MoTe2 channels with desirable performance, including long-term stability.

18.
J Dent Sci ; 15(4): 526-535, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33505626

RESUMO

BACKGROUND/PURPOSE: We previously found that the partially purified 30-100 kDa fraction of areca-nut-extract (ANE 30-100K) induces autophagy in different types of cells including oral carcinoma OECM-1 cells. This study was to analyze the composition and possible mechanisms of ANE 30-100K-induced autophagy (AIA). MATERIALS AND METHODS: Phenol-sulfuric acid method and high performance anion exchange chromatography were utilized to analyze the composition of ANE 30-100K. OECM-1 and esophageal CE81T/VGH cells were taken as the experimental models. Microscope and transmission electron microscope were used to observe morphological changes. Cell viability and specific proteins were respectively measured by XTT and Western bot assay. shRNA and chemical inhibitors were applied to assess the involvement of Atg5, caveolin, and proteasome in AIA. RESULTS: ANE 30-100K contains ∼67% carbohydrate, which is composed of fucose (5.938%), arabinose (24.631%), glucosamine (8.066%), galactose (26.820%), glucose (21.388%), and mannose (13.157%). After ANE 30-100K stimulation, CE81T/VGH cells showed intracellular vacuoles, acidic vesicles, double-membrane vacuoles, and elevated LC3-II level. ANE 30-100K-induced cytotoxicity and LC3-II accumulation were significantly inhibited by Atg5 knockdown. Furthermore, the endocytosis inhibitor (methyl-ß-cyclodextrin) and two caveolin shRNAs, as well as two proteasome inhibitors (lactacystin and epoxomicin), were shown to significantly attenuate ANE 30-100K-induced cytotoxicity and LC3-II accumulation in both OECM-1 and CE81T/VGH cells. CONCLUSION: The major components of ANE 30-100K are carbohydrates. CE81T/VGH also exhibited autophagic responses to ANE 30-100K. Caveolin-mediated endocytosis and proteasome are involved in AIA. This study may have provided new knowledges of the action mechanisms and compositions of ANE 30-100K.

19.
Sleep Med ; 65: 127-133, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31751907

RESUMO

OBJECTIVE: Limited information is currently available on 24-h ambulatory blood pressure (ABP) changes after adenotonsillectomy (T&A) in children with obstructive sleep apnea (OSA). In this study, the trajectory of 24-h ABP changes after surgery in children with OSA was examined at three-month and six-month follow-up. METHODS: Children aged 4-16 years with clinical symptoms of OSA and polysomnography (PSG)-diagnosed OSA (apnea-hypopnea index [AHI] >1) were included. All the children received T&A. PSG was conducted before and after surgery. Twenty four hour ABP was monitored using the linear mixed model before, three months after, and six months after surgery. RESULTS: In total, 122 children were examined (mean age: 7.9 years; 71% were boys). The AHI significantly decreased from 12.7 ± 16.7 to 2.4 ± 3.2 events/h after T&A (P < 0.001). Overall diastolic blood pressure (DBP; from 65.1 to 63.4 mmHg, P = 0.01) and night-time DBP (from 57.4 to 55.4 mmHg, P = 0.032) decreased nonsignificantly during the six-month postoperative period. The OSA children with presurgical hypertension exhibited significant reductions in overall systolic blood pressure (SBP), overall DBP, daytime DBP, night-time SBP, and night-time DBP at the three-month and six-month postoperative follow-up (all P < 0.05). The three-month and six-month ABP data did not differ significantly in the entire cohort, even between children with presurgical hypertension and non-hypertensive children. CONCLUSION: The 24-h ABP decreased significantly in the OSA children with hypertension at three and six months after surgery. Moreover, ABP findings did not differ significantly between the three- and six-month follow-up.


Assuntos
Adenoidectomia , Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea/fisiologia , Apneia Obstrutiva do Sono/cirurgia , Tonsilectomia , Criança , Feminino , Seguimentos , Humanos , Hipertensão/etiologia , Masculino , Polissonografia , Período Pós-Operatório
20.
Sci Rep ; 9(1): 20087, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31882987

RESUMO

In the present study, we aim to help improve the design of van der Waals stacking, i.e., vertical 2D electronics, by probing charge transport differences in both parallel and vertical conducting channels of layered molybdenum disulfide (MoS2), with thin graphite acting as source and drain electrodes. To avoid systematic errors and variable contact contributions to the MoS2 channel, parallel and vertical electronics are all fabricated and measured on the same conducting material. Large differences in the on/off current ratio, mobility, and charge fluctuations, between parallel and vertical electronics are evident in electrical performance as well as in charge transport mechanisms. Further insights are drawn from a well-constrained analysis of both temperature-dependent current-voltage characteristics and low-frequency (LF) current fluctuations. This work offers significant insight into the fundamental understanding of charge transport and the development of future layered-materials-based integration technology.

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