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1.
Int J Mol Sci ; 25(5)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38474118

RESUMO

c-Met is a tyrosine-kinase receptor, and its aberrant activation plays critical roles in tumorigenesis, invasion, and metastatic spread in many human tumors. PHA-665752 (PHA) is an inhibitor of c-Met and has antitumor effects on many hematological malignancies and solid cancers. However, the activation and expression of c-Met and its role and the antitumor effect of PHA on human oral squamous cell carcinoma (OSCC) cells remain unclear. Here, we investigated the activation and expression of c-Met and the effects of PHA on the growth of a highly tumorigenic HSC-3 human OSCC cell line with high c-Met phosphorylation and expression. Of note, c-Met was highly expressed and phosphorylated on Y1234/1235 in HSC-3 cells, and PHA treatment significantly suppressed the growth and induced apoptosis of these cells. Moreover, PHA that inhibited the phosphorylation (activation) of c-Met further caused the reduced phosphorylation and expression levels of Src, protein kinase B (PKB), mammalian target of rapamycin (mTtor), and myeloid cell leukemia-1 (Mcl-1) in HSC-3 cells. In addition, the antiangiogenic property of PHA in HSC-3 cells was shown, as evidenced by the drug's suppressive effect on the expression of hypoxia-inducible factor-1α (HIF-1α), a critical tumor angiogenic transcription factor. Importantly, genetic ablation of c-Met caused the reduced growth of HSC-3 cells and decreased Src phosphorylation and HIF-1α expression. Together, these results demonstrate that c-Met is highly activated in HSC-3 human oral cancer cells, and PHA exhibits strong antigrowth, proapoptotic, and antiangiogenic effects on these cells, which are mediated through regulation of the phosphorylation and expression of multiple targets, including c-Met, Src, PKB, mTOR, Mcl-1, and HIF-1α.


Assuntos
Carcinoma de Células Escamosas , Neoplasias Bucais , Sulfonas , Humanos , Neoplasias Bucais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides , Indóis , Subunidade alfa do Fator 1 Induzível por Hipóxia , Linhagem Celular Tumoral
2.
J Oral Implantol ; 48(4): 301-306, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-34522975

RESUMO

Non-nociceptive, persistent idiopathic facial pain (PIFP) is a poorly localized, continuous dull pain that occurs even in the absence of apparent pathological lesions or clinical neurologic deficiency. This study aimed to investigate the disease characteristics of PIFP that developed after dental implant treatment. The clinical characteristics of pain as well as treatment method and outcomes were retrospectively analyzed in 20 patients diagnosed with PIFP. The patients developed pain either after implant fixation or prosthetic treatment. In most patients, the pain persisted not only around the implant region but also at a distant site from the related implant (13/20, 65%). Many patients desired removal of the implants to manage the pain although the pain was not considered to be related to the implant treatment. In 12 patients, the related implants were removed, but 67% (n = 8/12) of the patients still experienced chronic pain after implant removal. Medication helped decrease the pain in most patients (n = 17). Pregabalin and clonazepam showed relatively higher efficiency than other medications for controlling the pain. The results showed that although the onset of PIFP was related to dental implant treatment, implant removal could not be considered a reliable option for the management of PIFP. Although medication controls the pain at least partially, complete pain control with medication should not be expected. These results demonstrate that an accurate diagnosis of PIFP is important for the selection of appropriate treatment.


Assuntos
Dor Crônica , Implantes Dentários , Dor Crônica/etiologia , Implantes Dentários/efeitos adversos , Dor Facial/diagnóstico , Dor Facial/tratamento farmacológico , Dor Facial/etiologia , Humanos , Estudos Retrospectivos
3.
Medicina (Kaunas) ; 58(6)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35744021

RESUMO

Background and objective: This study aimed to investigate the estimated rate and risk of recurrence of uncomplicated diverticulitis (UCD) after the first episode through a meta-analysis. Methods: Eligible studies were searched and reviewed; 27 studies were included in this study. Subgroup analyses were performed, based on lesion location, medical treatment, follow-up period, and study location. Results: The estimated recurrence rate of UCD was 0.129 (95% confidence interval [CI] 0.102-0.162). The recurrence rates of the right-and left-sided colon were 0.092 (95% CI 27.063-0.133) and 0.153 (95% CI 0.104-0.218), respectively. The recurrence rate according to follow-up period was highest in the subgroup 1-2 years, compared with that of other subgroups. The recurrence rate of the Asian subgroup was significantly lower than that of the non-Asian subgroup (0.092, 95% CI 0.064-0.132 vs. 0.147, 95% CI 0.110-0.192; p = 0.043 in the meta-regression test). There were significant correlations between UCD recurrence and older age and higher body temperature. However, UCD recurrence was not significantly correlated with medications, such as antibiotics or anti-inflammatory drugs. Conclusions: In this study, detailed information on estimated recurrence rates of UCD was obtained. In addition, older age and higher body temperature may be risk factors for UCD recurrence after the first episode.


Assuntos
Doença Diverticular do Colo , Diverticulite , Diverticulite/terapia , Doença Diverticular do Colo/epidemiologia , Humanos , Recidiva , Fatores de Risco , Resultado do Tratamento
4.
J Cell Mol Med ; 25(17): 8300-8311, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34318593

RESUMO

Dasatinib is an inhibitor of Src that has anti-tumour effects on many haematological and solid cancers. However, the anti-tumour effects of dasatinib on human oral cancers remain unclear. In this study, we investigated the effects of dasatinib on different types of human oral cancer cells: the non-tumorigenic YD-8 and YD-38 and the tumorigenic YD-10B and HSC-3 cells. Strikingly, dasatinib at 10 µM strongly suppressed the growth and induced apoptosis of YD-38 cells and inhibited the phosphorylation of Src, EGFR, STAT-3, STAT-5, PKB and ERK-1/2. In contrast, knockdown of Src blocked the phosphorylation of EGFR, STAT-5, PKB and ERK-1/2, but not STAT-3, in YD-38 cells. Dasatinib induced activation of the intrinsic caspase pathway, which was inhibited by z-VAD-fmk, a pan-caspase inhibitor. Dasatinib also decreased Mcl-1 expression and S6 phosphorylation while increased GRP78 expression and eIF-2α phosphorylation in YD-38 cells. In addition, to its direct effects on YD-38 cells, dasatinib also exhibited anti-angiogenic properties. Dasatinib-treated YD-38 or HUVEC showed reduced HIF-1α expression and stability. Dasatinib alone or conditioned media from dasatinib-treated YD-38 cells inhibited HUVEC tube formation on Matrigel without affecting HUVEC viability. Importantly, dasatinib's anti-growth, anti-angiogenic and pro-apoptotic effects were additionally seen in tumorigenic HSC-3 cells. Together, these results demonstrate that dasatinib has strong anti-growth, anti-angiogenic and pro-apoptotic effects on human oral cancer cells, which are mediated through the regulation of multiple targets, including Src, EGFR, STAT-3, STAT-5, PKB, ERK-1/2, S6, eIF-2α, GRP78, caspase-9/3, Mcl-1 and HIF-1α.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Dasatinibe/farmacologia , Neoplasias Bucais/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Linhagem Celular Tumoral , Humanos
5.
Small ; 17(18): e2007297, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33729684

RESUMO

Shape memory materials have been successfully applied to minimally invasive implantation of medical devices. However, organ-movement-specific shape programing at a microscale level has never been demonstrated despite significant unmet needs. As vein-to-artery grafting induces vein dilation and stenosis, a polymeric self-enclosable external support (SES) is designed to wrap the vascular out-wall. Its micropores are programmed to increase sizes and interconnections upon dilation. Vessel dilation promotes venous maturation, but overdilation induces stenosis by disturbed blood flow. Therefore, the unique elastic shape-fixity of SES provides a foundation to enable a stable microscale shape transition by maintaining the vein dilation. The shape transition of micropore architecture upon dilation induces beneficial inflammation, thereby regenerating vasa vasorum and directing smooth muscle cell migration toward adventitia with the consequent muscle reinforcement of veins. This game-changer approach prevents the stenosis of vein-to-artery grafting by rescuing ischemic disorders and promoting arterial properties of veins.


Assuntos
Vasa Vasorum , Doenças Vasculares , Constrição Patológica , Dilatação , Humanos , Doenças Vasculares/prevenção & controle , Veias
6.
Small ; 16(16): e2000012, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32239653

RESUMO

Atherosclerosis development leads to irreversible cascades, highlighting the unmet need for improved methods of early diagnosis and prevention. Disturbed flow formation is one of the earliest atherogenic events, resulting in increased endothelial permeability and subsequent monocyte recruitment. Here, a mesenchymal stem cell (MSC)-derived nanovesicle (NV) that can target disturbed flow sites with the peptide GSPREYTSYMPH (PREY) (PMSC-NVs) is presented which is selected through phage display screening of a hundred million peptides. The PMSC-NVs are effectively produced from human MSCs (hMSCs) using plasmid DNA designed to functionalize the cell membrane with PREY. The potent anti-inflammatory and pro-endothelial recovery effects are confirmed, similar to those of hMSCs, employing mouse and porcine partial carotid artery ligation models as well as a microfluidic disturbed flow model with human carotid artery-derived endothelial cells. This nanoscale platform is expected to contribute to the development of new theragnostic strategies for preventing the progression of atherosclerosis.


Assuntos
Aterosclerose/terapia , Células-Tronco Mesenquimais , Nanopartículas , Animais , Artérias Carótidas , Células Endoteliais , Humanos , Ligadura , Camundongos , Suínos
7.
Adv Exp Med Biol ; 1249: 131-140, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32602095

RESUMO

The field of tissue regeneration has seen a paradigm shift after one wave of technological innovation after another, which has notably made significant contributions to basic cellular response control and overall tissue regeneration. One particular area that is seeing rekindled interest after technological innovation is managing cell migration toward defects because successful host cell migration from adjacent tissue can accelerate overall regeneration time in tissue defects that are either large in size or irregular in shape. This chapter surveys significant advances on directed cell migration upon topological cues. First, we introduce several examples of patterning and electrospinning technology for guiding directed cell migration, followed by a discussion on approaches to influencing radially aligned topography in pattern or electrospun sheet for overall tissue regeneration.


Assuntos
Movimento Celular , Regeneração , Engenharia Tecidual , Humanos
8.
Adv Exp Med Biol ; 1064: 237-251, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30471037

RESUMO

Stimuli-responsive biomaterials undergo significant alterations in material structure and property in response to changes of local environmental factors (e.g. pH, temperature, enzyme activation, and water absorption). In particular, reactive oxygen species (ROS) is considered as a major stimulus because over-production of ROS involves most types of major pathogenesis. The application of ROS-responsive biomaterials requires suitable material designs to program user-defined changes of their structure and property in response to a sudden change in the local ROS level. This chapter summarizes the progress in designing and applying major types of ROS-responsive biomaterials within the past 10 years.


Assuntos
Materiais Biocompatíveis/química , Espécies Reativas de Oxigênio/química
9.
J Craniofac Surg ; 28(7): e700-e704, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28891902

RESUMO

PURPOSE: This study was aimed to evaluate the nasal deviation in patients with asymmetric mandibular prognathism. MATERIALS AND METHODS: Thirty-five patients with skeletal class III malocclusion were included in the study. Significant mandibular asymmetry of >4 mm menton deviation in three-dimensional (3D) reformatted cone beam computed tomography images was defined as asymmetry group (n = 20). Patients without mandibular asymmetry served as control group (n = 15). The mandibular asymmetry was evaluated pre- and postoperatively. RESULTS: Nasal tip was significantly shifted to the deviated side of the mandible (short side) in the asymmetry group, as compared to the control group (1.5 ±â€Š0.9 degree, P < 0.01). Alar base angle (ABA) was significantly narrower in nondeviated side (long side) than in the deviated side in asymmetry group. However, control group showed no bilateral difference in ABA. Correction of deviated mandibular prognathism by isolated mandibular surgery resulted in change in the ABA but not the columella base position or nasal asymmetry. ABA on nondeviated side significantly decreased in proportion to the amount of transverse menton movement by surgery (r = -0.560, P < 0.01). CONCLUSION: Our results showed that mandibular chin deviation was accompanied by nasal deviation. Isolated mandibular surgery can potentially influence the alar base position on the contralateral side of deviation but not the nasal tip asymmetry. Therefore, clinicians should inform patients preoperatively of the fundamental limitation of mandibular surgery in cases with preexisting nasal asymmetry.


Assuntos
Má Oclusão Classe III de Angle , Nariz , Estudos de Coortes , Tomografia Computadorizada de Feixe Cônico , Assimetria Facial , Humanos , Má Oclusão Classe III de Angle/diagnóstico por imagem , Má Oclusão Classe III de Angle/epidemiologia , Má Oclusão Classe III de Angle/patologia , Nariz/diagnóstico por imagem , Nariz/patologia
10.
Biomacromolecules ; 16(9): 2541-55, 2015 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-26280621

RESUMO

Current advances in biomaterial fabrication techniques have broadened their application in different realms of biomedical engineering, spanning from drug delivery to tissue engineering. The success of biomaterials depends highly on the ability to modulate cell and tissue responses, including cell adhesion, as well as induction of repair and immune processes. Thus, most recent approaches in the field have concentrated on functionalizing biomaterials with different biomolecules intended to evoke cell- and tissue-specific reactions. Marine mussels produce mussel adhesive proteins (MAPs), which help them strongly attach to different surfaces, even under wet conditions in the ocean. Inspired by mussel adhesiveness, scientists discovered that dopamine undergoes self-polymerization at alkaline conditions. This reaction provides a universal coating for metals, polymers, and ceramics, regardless of their chemical and physical properties. Furthermore, this polymerized layer is enriched with catechol groups that enable immobilization of primary amine or thiol-based biomolecules via a simple dipping process. Herein, this review explores the versatile surface modification techniques that have recently been exploited in tissue engineering and summarizes polydopamine polymerization mechanisms, coating process parameters, and effects on substrate properties. A brief discussion of polydopamine-based reactions in the context of engineering various tissue types, including bone, blood vessels, cartilage, nerves, and muscle, is also provided.


Assuntos
Bivalves/química , Materiais Revestidos Biocompatíveis/química , Dopamina/química , Indóis/química , Polímeros/química , Proteínas/química , Engenharia Tecidual/métodos , Animais , Humanos , Camundongos , Células NIH 3T3 , Propriedades de Superfície
11.
J Plast Reconstr Aesthet Surg ; 88: 257-265, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38007998

RESUMO

BACKGROUND: Panfacial bone fractures pose intricate challenges because of severe fragmentation and the loss of landmarks. Surgeons use a variety of reduction techniques, including bottom-up and top-down approaches. This single proportional meta-analysis explores sequencing differences and complications between oral and maxillofacial surgery surgeons (OMSs) and plastic and reconstructive surgeons (PRSs) in treating panfacial bone fractures. METHODS: The PubMed and Scopus databases were searched systematically, and we compiled 14 studies published between 2007 and 2023 involving 1238 patients. A systematic review of the included studies was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, and data on the reduction techniques; total complication rates; and rates of malocclusion, enophthalmos, infection, asymmetry, and esthetic complications were collected. RESULTS: The bottom-up technique was the most prevalent for both types of surgeons (57.1%, 8 out of 14). Malocclusion rates (I2 = 0% for OMSs and 41% for PRSs) were similar between the groups (p = 0.72), but PRSs tended to have a lower enophthalmos rate (I2 = 0% for OMSs and 32% for PRSs) than OMSs (p < 0.01). Infection rates remained consistent across all studies. However, high heterogeneity was observed for the total complication rate (I2 = 94% for OMSs and 85% for PRSs) and asymmetry and esthetic complications (I2 = 88% for OMSs and 92% for PRSs), making direct comparison between the two groups inconclusive. CONCLUSIONS: In this study, the differences in surgical techniques and levels of interest have a greater impact on the outcomes of the panfacial bone fracture than the surgeon's specialty. However, more in-depth studies are needed to accurately pinpoint panfacial bone fracture reduction trends and differences in postoperative complications in the two expert groups.


Assuntos
Enoftalmia , Fraturas Ósseas , Má Oclusão , Cirurgiões , Humanos , Ossos Faciais/cirurgia , Fraturas Ósseas/cirurgia , Má Oclusão/epidemiologia , Má Oclusão/etiologia
12.
Tissue Eng Regen Med ; 21(1): 1-19, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38066355

RESUMO

BACKGROUND: Exosomes, nano-sized vesicles ranging between 30 and 150 nm secreted by human cells, play a pivotal role in long-range intercellular communication and have attracted significant attention in the field of regenerative medicine. Nevertheless, their limited productivity and cost-effectiveness pose challenges for clinical applications. These issues have recently been addressed by cell-derived nanovesicles (CDNs), which are physically synthesized exosome-mimetic nanovesicles from parent cells, as a promising alternative to exosomes. CDNs exhibit structural, physical, and biological properties similar to exosomes, containing intracellular protein and genetic components encapsulated by the cell plasma membrane. These characteristics allow CDNs to be used as regenerative medicine and therapeutics on their own, or as a drug delivery system. METHODS: The paper reviews diverse methods for CDN synthesis, current analysis techniques, and presents engineering strategies to improve lesion targeting efficiency and/or therapeutic efficacy. RESULTS: CDNs, with their properties similar to those of exosomes, offer a cost-effective and highly productive alternative due to their non-living biomaterial nature, nano-size, and readiness for use, allowing them to overcome several limitations of conventional cell therapy methods. CONCLUSION: Ongoing research and enhancement of CDNs engineering, along with comprehensive safety assessments and stability analysis, exhibit vast potential to advance regenerative medicine by enabling the development of efficient therapeutic interventions.


Assuntos
Exossomos , Humanos , Exossomos/metabolismo , Sistemas de Liberação de Medicamentos , Medicina Regenerativa
13.
Int J Mol Sci ; 14(6): 11011-23, 2013 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-23708101

RESUMO

In this study, we developed a one step process to synthesize nanogel containing silver nanoparticles involving electron beam irradiation. Water-soluble silver nitrate powder is dissolved in the distilled water and then poly(acrylic acid) (PAAc) and hexane are put into this silver nitrate solution. These samples are irradiated by an electron beam to make the PAAc nanogels containing silver nanoparticles (Ag/PAAc nanogels). The nanoparticles were characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). In addition, the particle size and zeta-potential were confirmed by a particle size analyzer (PSA). The antibacterial properties of the nanogels were evaluated by paper diffusion test. The Ag/PAAc nanogels had an antibacterial effect against Escherichia coli and Staphylococcus aureus. The nanogels also demonstrated a good healing effect against diabetic ulcer. The size of the Ag/PAAc nanogels decreased with increasing irradiation doses, and the absolute value of the zeta potential increased with increasing irradiation doses. Also, the Ag/PAAc nanogels exhibited good antibacterial activity against both Gram-negative and Gram-positive bacteria. In in vivo wound healing, the Ag/PAAc nanogels have a good healing effect.


Assuntos
Resinas Acrílicas/farmacologia , Anti-Infecciosos/farmacologia , Elétrons , Nanopartículas Metálicas/química , Polietilenoglicóis/farmacologia , Polietilenoimina/farmacologia , Prata/farmacologia , Animais , Escherichia coli/efeitos dos fármacos , Feminino , Camundongos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Nanogéis , Tamanho da Partícula , Espectrometria por Raios X , Espectrofotometria Ultravioleta , Staphylococcus aureus/efeitos dos fármacos , Eletricidade Estática , Cicatrização/efeitos dos fármacos
14.
Sci Adv ; 9(12): eadd4210, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36947623

RESUMO

The stemness of bone marrow mesenchymal stem cells (BMSCs) is maintained by hypoxia. The oxygen level increases from vessel-free cartilage to hypoxic bone marrow and, furthermore, to vascularized bone, which might direct the chondrogenesis to osteogenesis and regenerate the skeletal system. Hence, oxygen was diffused from relatively low to high levels throughout a three-dimensional chip. When we cultured BMSCs in the chip and implanted them into the rabbit defect models of low-oxygen cartilage and high-oxygen calvaria bone, (i) the low oxygen level (base) promoted stemness and chondrogenesis of BMSCs with robust antioxidative potential; (ii) the middle level (two times ≥ low) pushed BMSCs to quiescence; and (iii) the high level (four times ≥ low) promoted osteogenesis by disturbing the redox balance and stemness. Last, endochondral or intramembranous osteogenesis upon transition from low to high oxygen in vivo suggests a developmental mechanism-driven solution to promote chondrogenesis to osteogenesis in the skeletal system by regulating the oxygen environment.


Assuntos
Medula Óssea , Cartilagem , Animais , Coelhos , Osteogênese , Oxigênio , Hipóxia , Células da Medula Óssea , Células Cultivadas , Diferenciação Celular
15.
Biomacromolecules ; 13(7): 2020-8, 2012 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-22617001

RESUMO

Most polymeric vascular prosthetic materials have low patency rate for replacement of small diameter vessels (<5 mm), mainly due to failure to generate healthy endothelium. In this study, we present polydopamine-mediated immobilization of growth factors on the surface of polymeric materials as a versatile tool to modify surface characteristics of vascular grafts potentially for accelerated endothelialization. Polydopamine was deposited on the surface of biocompatible poly(L-lactide-co-ε-caprolactone) (PLCL) elastomer, on which vascular endothelial growth factor (VEGF) was subsequently immobilized by simple dipping. Surface characteristics and composition were investigated by using scanning electron microscopy, atomic force microscopy, and X-ray photoelectron spectroscopy. Immobilization of VEGF on the polydopamine-deposited PLCL films was effective (19.8 ± 0.4 and 197.4 ± 19.7 ng/cm(2) for DPv20 and DPv200 films, respectively), and biotin-mediated labeling of immobilized VEGF revealed that the fluorescence intensity increased as a function of the concentration of VEGF solution. The effect of VEGF on adhesion of HUVECs was marginal, which may have been masked by polydopamine layer that also enhanced cell adhesion. However, VEGF-immobilized substrate significantly enhanced proliferation of HUVECs for over 7 days of in vitro culture and also improved their migration. In addition, immobilized VEGF supported robust cell to cell interactions with strong expression of CD 31 marker. The same process was effective for immobilization of basic fibroblast growth factor, demonstrating the robustness of polydopamine layer for secondary ligation of growth factors as a simple and novel surface modification strategy for vascular graft materials.


Assuntos
Prótese Vascular , Proteínas Imobilizadas/química , Fator A de Crescimento do Endotélio Vascular/química , Animais , Bivalves , Adesão Celular , Movimento Celular , Proliferação de Células , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Indóis/química , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Poliésteres/química , Polímeros/química , Propriedades de Superfície , Molhabilidade
16.
Phys Chem Chem Phys ; 14(14): 4789-95, 2012 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-22382807

RESUMO

The electronic band structure at the Zn(1-x)Mg(x)O/Cu(In(0.7)Ga(0.3))Se(2) interface was investigated for its potential application in Cd-free Cu(In,Ga)Se(2) thin film solar cells. Zn(1-x)Mg(x)O thin films with various Mg contents were grown by atomic layer deposition on Cu(In(0.7)Ga(0.3))Se(2) absorbers, which were deposited by the co-evaporation of Cu, In, Ga, and Se elemental sources. The electron emissions from the valence band and core levels were measured by a depth profile technique using X-ray and ultraviolet photoelectron spectroscopy. The valence band maximum positions are around 3.17 eV for both Zn(0.9)Mg(0.1)O and Zn(0.8)Mg(0.2)O films, while the valence band maximum value for CIGS is 0.48 eV. As a result, the valence band offset value between the bulk Zn(1-x)Mg(x)O (x = 0.1 and x = 0.2) region and the bulk CIGS region was 2.69 eV. The valence band offset value at the Zn(1-x)Mg(x)O/CIGS interface was found to be 2.55 eV after considering a small band bending in the interface region. The bandgap energy of Zn(1-x)Mg(x)O films increased from 3.25 to 3.76 eV as the Mg content increased from 0% to 25%. The combination of the valence band offset values and the bandgap energy of Zn(1-x)Mg(x)O films results in the flat (0 eV) and cliff (-0.23 eV) conduction band alignments at the Zn(0.8)Mg(0.2)O/Cu(In(0.7)Ga(0.3))Se(2) and Zn(0.9)Mg(0.1)O/Cu(In(0.7)Ga(0.3))Se(2) interfaces, respectively. The experimental results suggest that the bandgap energy of Zn(1-x)Mg(x)O films is the main factor that determines the conduction band offset at the Zn(1-x)Mg(x)O/Cu(In(0.7)Ga(0.3))Se(2) interface. Based on these results, we conclude that a Zn(1-x)Mg(x)O film with a relatively high bandgap energy is necessary to create a suitable conduction band offset at the Zn(1-x)Mg(x)O/CIGS interface to obtain a robust heterojunction. Also, ALD Zn(1-x)Mg(x)O films can be considered as a promising alternative buffer material to replace the toxic CdS for environmental safety.

17.
Zootaxa ; 5099(4): 450-474, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35391403

RESUMO

This study identifies the number of named and described species of three monotrysian, plant-mining lepidopteran families worldwide: Nepticulidae and Opostegidae (Nepticuloidea), and Tischeriidae (Tischerioidea). At the end of 2021, we estimated that a total of 1000 Nepticulidae species, 197 Opostegidae species, and 170 Tischeriidae species have been described since the taxonomic practice of describing species began in the 18th century. We examine and discuss the history of descriptions and authorship of species worldwide for each of the three families. We found that the total (accumulative) number of species described increased with each time period delineated. About five new species were described per year on average, or about 22 new species were described per year in the 21st century. We recognize researchers with the most number of described species in these three taxa.


Assuntos
Lepidópteros , Mariposas , Distribuição Animal , Animais , Humanos , Plantas
18.
Insects ; 13(12)2022 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-36555017

RESUMO

In this study, 29 species of Caloptilia Hübner, 1825, belonging to the family Gracillariidae, were recognized in Korea. Among these, three species, i.e., C. purpureus sp. nov., C. koreana sp. nov., and C. xanthos sp. nov., are described as new to science. In addition, seven species of this genus are reported for the first time in Korea. All known species were enumerated, based on their available information. Adult specimens and genitalia of the new and newly recorded species were examined and described using all available information.

19.
Adv Healthc Mater ; 11(8): e2102226, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34963195

RESUMO

Glioblastoma (GBM) is one of the most intractable tumor types due to the progressive drug resistance upon tumor mass expansion. Incremental hypoxia inside the growing tumor mass drives epigenetic drug resistance by activating nongenetic repair of antiapoptotic DNA, which could be impaired by drug treatment. Hence, rescuing intertumor hypoxia by oxygen-generating microparticles may promote susceptibility to antitumor drugs. Moreover, a tumor-on-a-chip model enables user-specified alternation of clinic-derived samples. This study utilizes patient-derived glioblastoma tissue to generate cell spheroids with size variations in a 3D microchannel network chip (GBM chip). As the spheroid size increases, epigenetic drug resistance is promoted with inward hypoxia severance, as supported by the spheroid size-proportional expression of hypoxia-inducible factor-1a in the chip. Loading antihypoxia microparticles onto the spheroid surface significantly reduces drug resistance by silencing the expression of critical epigenetic factor, resulting in significantly decreased cell invasiveness. The results are confirmed in vitro using cell line and patient samples in the chip as well as chip implantation into a hypoxic hindlimb ischemia model in mice, which is an unprecedented approach in the field.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Resistência a Medicamentos , Epigênese Genética , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Humanos , Hipóxia , Camundongos
20.
Bioact Mater ; 18: 433-445, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35415304

RESUMO

All-in-one treatments represent a paradigm shift in future medicine. For example, inflammatory bowel disease (IBD) is mainly diagnosed by endoscopy, which could be applied for not only on-site monitoring but also the intestinal lesion-targeted spray of injectable hydrogels. Furthermore, molecular conjugation to the hydrogels would program both lesion-specific adhesion and drug-free therapy. This study validated this concept of all-in-one treatment by first utilizing a well-known injectable hydrogel that underwent efficient solution-to-gel transition and nanomicelle formation as a translatable component. These properties enabled spraying of the hydrogel onto the intestinal walls during endoscopy. Next, peptide conjugation to the hydrogel guided endoscopic monitoring of IBD progress upon adhesive gelation with subsequent moisturization of inflammatory lesions, specifically by nanomicelles. The peptide was designed to mimic the major component that mediates intestinal interaction with Bacillus subtilis flagellin during IBD initiation. Hence, the peptide-guided efficient adhesion of the hydrogel nanomicelles onto Toll-like receptor 5 (TLR5) as the main target of flagellin binding and Notch-1. The peptide binding potently suppressed inflammatory signaling without drug loading, where TLR5 and Notch-1 operated collaboratively through downstream actions of tumor necrosis factor-alpha. The results were produced using a human colorectal cell line, clinical IBD patient cells, gut-on-a-chip, a mouse IBD model, and pig experiments to validate the translational utility.

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