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1.
Clin Genitourin Cancer ; 21(6): e467-e473, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37301665

RESUMEN

PURPOSE: Eligibility criteria illustrate the characteristics of the study population and promote the safety of participants. However, overreliance on restrictive eligibility criteria may limit the generalizability of outcomes. As a result, the American Society of Clinical Oncology (ASCO) and Friends of Cancer Research (Friends) issued statements to curtail these challenges. In this study, we aimed to assess restrictiveness in eligibility criteria across advanced prostate cancer clinical trials. MATERIALS AND METHODS: We identified all phase I, II, and III advanced prostate cancer clinical trials between June 30, 2012, and June 30, 2022, through Clinicaltrials.gov. We evaluated whether a clinical trial excluded, conditionally included, or did not report 4 common criteria: brain metastases, prior or concurrent malignancies, HIV infection, and hepatitis B virus (HBV)/hepatitis C virus (HCV) infection. Performance status (PS) criteria were recorded based on the Eastern Cooperative Oncology Group (ECOG) scale. RESULTS: Out of 699 clinical trials within our search strategy, 265 (37.9%) trials possessed all the required data and were included in our analysis. The most common excluded condition of our interest was brain metastases (60.8%), followed by HIV positivity (46.4%), HBV/HCV positivity (46.0%), and concurrent malignancies (15.5%). Additionally, 50.9% of clinical trials only included patients with ECOG PS 0 to 1. HIV and HBV/HCV infection were exclusion criteria of 22 (80.8%) and 19 (73.1%) immunotherapy trials, respectively. CONCLUSION: Patients with brain metastases, prior or concurrent malignancies, HIV infection, HBV/HCV infection, or low-functioning PS were overly restricted from participating in advanced prostate clinical trials. Advocating for broader criteria may ameliorate generalizability.


Asunto(s)
Neoplasias Encefálicas , Infecciones por VIH , Hepatitis C , Neoplasias de la Próstata , Masculino , Humanos , Infecciones por VIH/tratamiento farmacológico , Amigos , Neoplasias de la Próstata/terapia , Oncología Médica
2.
Animal Model Exp Med ; 6(2): 120-130, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36856186

RESUMEN

Understanding the bioelectrical properties of bone tissue is key to developing new treatment strategies for bone diseases and injuries, as well as improving the design and fabrication of scaffold implants for bone tissue engineering. The bioelectrical properties of bone tissue can be attributed to the interaction of its various cell lineages (osteocyte, osteoblast and osteoclast) with the surrounding extracellular matrix, in the presence of various biomechanical stimuli arising from routine physical activities; and is best described as a combination and overlap of dielectric, piezoelectric, pyroelectric and ferroelectric properties, together with streaming potential and electro-osmosis. There is close interdependence and interaction of the various electroactive and electrosensitive components of bone tissue, including cell membrane potential, voltage-gated ion channels, intracellular signaling pathways, and cell surface receptors, together with various matrix components such as collagen, hydroxyapatite, proteoglycans and glycosaminoglycans. It is the remarkably complex web of interactive cross-talk between the organic and non-organic components of bone that define its electrophysiological properties, which in turn exerts a profound influence on its metabolism, homeostasis and regeneration in health and disease. This has spurred increasing interest in application of electroactive scaffolds in bone tissue engineering, to recapitulate the natural electrophysiological microenvironment of healthy bone tissue to facilitate bone defect repair.


Asunto(s)
Regeneración Ósea , Andamios del Tejido , Ingeniería de Tejidos , Huesos , Durapatita
3.
Adv Sci (Weinh) ; 10(2): e2204502, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36453574

RESUMEN

Bone degeneration associated with various diseases is increasing due to rapid aging, sedentary lifestyles, and unhealthy diets. Living bone tissue has bioelectric properties critical to bone remodeling, and bone degeneration under various pathological conditions results in significant changes to these bioelectric properties. There is growing interest in utilizing biomimetic electroactive biomaterials that recapitulate the natural electrophysiological microenvironment of healthy bone tissue to promote bone repair. This review first summarizes the etiology of degenerative bone conditions associated with various diseases such as type II diabetes, osteoporosis, periodontitis, osteoarthritis, rheumatoid arthritis, osteomyelitis, and metastatic osteolysis. Next, the diverse array of natural and synthetic electroactive biomaterials with therapeutic potential are discussed. Putative mechanistic pathways by which electroactive biomaterials can mitigate bone degeneration are critically examined, including the enhancement of osteogenesis and angiogenesis, suppression of inflammation and osteoclastogenesis, as well as their anti-bacterial effects. Finally, the limited research on utilization of electroactive biomaterials in the treatment of bone degeneration associated with the aforementioned diseases are examined. Previous studies have mostly focused on using electroactive biomaterials to treat bone traumatic injuries. It is hoped that this review will encourage more research efforts on the use of electroactive biomaterials for treating degenerative bone conditions.


Asunto(s)
Diabetes Mellitus Tipo 2 , Osteoporosis , Humanos , Materiales Biocompatibles/uso terapéutico , Osteogénesis , Huesos
4.
Bioact Mater ; 20: 81-92, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35633875

RESUMEN

Stem cells from human exfoliated deciduous teeth (SHED) uniquely exhibit high proliferative and neurogenic potential. Charged biomaterials have been demonstrated to promote neural differentiation of stem cells, but the dose-response effect of electrical stimuli from these materials on neural differentiation of SHED remains to be elucidated. Here, by utilizing different annealing temperatures prior to corona poling treatment, BaTiO3/P(VDF-TrFE) ferroelectric nanocomposite membranes with varying charge polarization intensity (d 33 ≈ 0, 4, 12 and 19 pC N-1) were fabricated. Enhanced expression of neural markers, increased cell elongation and more prominent neurite outgrowths were observed with increasing surface charge of the nanocomposite membrane indicating a dose-response effect of surface electrical charge on SHED neural differentiation. Further investigations of the underlying molecular mechanisms revealed that intracellular calcium influx, focal adhesion formation, FAK-ERK mechanosensing pathway and neurogenic-related ErbB signaling pathway were implicated in the enhancement of SHED neural differentiation by surface electrical charge. Hence, this study confirms the dose-response effect of biomaterial surface charge on SHED neural differentiation and provides preliminary insights into the molecular mechanisms and signaling pathways involved.

5.
Int J Oral Sci ; 14(1): 13, 2022 02 24.
Artículo en Inglés | MEDLINE | ID: mdl-35210393

RESUMEN

The high neurogenic potential of dental and oral-derived stem cells due to their embryonic neural crest origin, coupled with their ready accessibility and easy isolation from clinical waste, make these ideal cell sources for neuroregeneration therapy. Nevertheless, these cells also have high propensity to differentiate into the osteo-odontogenic lineage. One strategy to enhance neurogenesis of these cells may be to recapitulate the natural physiological electrical microenvironment of neural tissues via electroactive or electroconductive tissue engineering scaffolds. Nevertheless, to date, there had been hardly any such studies on these cells. Most relevant scientific information comes from neurogenesis of other mesenchymal stem/stromal cell lineages (particularly bone marrow and adipose tissue) cultured on electroactive and electroconductive scaffolds, which will therefore be the focus of this review. Although there are larger number of similar studies on neural cell lines (i.e. PC12), neural stem/progenitor cells, and pluripotent stem cells, the scientific data from such studies are much less relevant and less translatable to dental and oral-derived stem cells, which are of the mesenchymal lineage. Much extrapolation work is needed to validate that electroactive and electroconductive scaffolds can indeed promote neurogenesis of dental and oral-derived stem cells, which would thus facilitate clinical applications in neuroregeneration therapy.


Asunto(s)
Células Madre Mesenquimatosas , Células-Madre Neurales , Diferenciación Celular , Células Madre Mesenquimatosas/metabolismo , Células-Madre Neurales/metabolismo , Neurogénesis , Andamios del Tejido
6.
J Biomed Nanotechnol ; 17(6): 1058-1067, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34167620

RESUMEN

Ferroelectric biomaterials have been widely investigated and demonstrated to enhance osteogenesis by simulating the inherent electrical properties of bone tissues. Nevertheless, the underlying biological processes are still not wellunderstood. Hence, this study investigated the underlying biological processes by which bone piezoelectricity-mimicking barium titanate/poly(vinylidene fluoride-trifluoroethylene) nanocomposite membranes (BTO nanocomposite membranes) promote osteogenesis of Bone Marrow Mesenchymal Stem Cells (BMSCs). Ourresults revealed that the piezoelectric coefficient (d33) of nanocomposite membranes aftercontrolled corona poling was similar to that of native bone, and exhibited highly-stable piezoelectrical properties and concentrated surface electrical potential. These nanocomposite membranes significantly enhanced the adhesion and spreading of BMSCs, which was manifested as increased number and area of mature focal adhesions. Furthermore, the nanocomposite membranes significantly promoted the expression of integrin receptors genes (α1, α5 andß3), which in turn enhanced osteogenesis of BMSCs, as manifested by upregulated Alkaline Phosphatase (ALP) and Bone Morphogenetic Protein 2 (BMP2) expression levels. Further investigations found that the Focal Adhesion Kinase (FAK)-Extracellular Signal-Regulated Kinase1/2 (ERK 1/2) signaling axis may be involved in the biological process of polarized nanocomposite membrane-induced osteogenesis. This study thus provides useful insights for betterunderstanding of the biological processes by which piezoelectric or ferroelectric biomaterials promote osteogenesis.


Asunto(s)
Células Madre Mesenquimatosas , Nanocompuestos , Citoesqueleto de Actina , Células de la Médula Ósea , Huesos , Adhesión Celular , Diferenciación Celular , Células Cultivadas , Osteogénesis
7.
Cell Mol Life Sci ; 78(2): 497-512, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32748155

RESUMEN

YAP and TAZ are ubiquitously expressed homologous proteins originally identified as penultimate effectors of the Hippo signaling pathway, which plays a key role in maintaining mammalian tissue/organ size. Presently, it is known that YAP/TAZ also interact with various non-Hippo signaling pathways, and have diverse roles in multiple biological processes, including cell proliferation, tissue regeneration, cell lineage fate determination, tumorigenesis, and mechanosensing. In this review, we first examine the various microenvironmental cues and signaling pathways that regulate YAP/TAZ activation, through the Hippo and non-Hippo signaling pathways. This is followed by a brief summary of the interactions of YAP/TAZ with TEAD1-4 and a diverse array of other non-TEAD transcription factors. Finally, we offer a critical perspective on how increasing knowledge of the regulatory mechanisms of YAP/TAZ signaling might open the door to novel therapeutic applications in the interrelated fields of biomaterials, tissue engineering, regenerative medicine and synthetic biology.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Transducción de Señal , Transactivadores/metabolismo , Factores de Transcripción/metabolismo , Animales , Carcinogénesis/metabolismo , Comunicación Celular , Vía de Señalización Hippo , Humanos , Mapas de Interacción de Proteínas , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores Notch/metabolismo , Proteínas Coactivadoras Transcripcionales con Motivo de Unión a PDZ , Proteínas Señalizadoras YAP
8.
Front Cell Dev Biol ; 8: 735, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32850847

RESUMEN

The penultimate effectors of the Hippo signaling pathways YAP and TAZ, are transcriptional co-activator proteins that play key roles in many diverse biological processes, ranging from cell proliferation, tumorigenesis, mechanosensing and cell lineage fate determination, to wound healing and regeneration. In this review, we discuss the regulatory mechanisms by which YAP/TAZ control stem/progenitor cell differentiation into the various major lineages that are of interest to tissue engineering and regenerative medicine applications. Of particular interest is the key role of YAP/TAZ in maintaining the delicate balance between quiescence, self-renewal, proliferation and differentiation of endogenous adult stem cells within various tissues/organs during early development, normal homeostasis and regeneration/healing. Finally, we will consider how increasing knowledge of YAP/TAZ signaling might influence the trajectory of future progress in regenerative medicine.

9.
Small ; 15(14): e1802995, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30821114

RESUMEN

2D group-III nitride materials have shown a great promise for applications in optoelectronic devices thanks to their thickness-dependent properties. However, the epitaxial growth of 2D group-III nitrides remains a challenge. In this work, epitaxial growth of 2D GaN with well-controlled lattice structures and bandgaps is achieved by plasma-enhanced metal organic chemical vapor deposition via effective regulation of plasma energy and growth temperature. The structure of graphene/2D GaN/Si heterostructures is carefully investigated by high-resolution transmission electron microscopy. The formation mechanism of the 2D GaN layer is clearly clarified by theoretical calculations. Furthermore, a bandgap for 2D GaN ranging from ≈4.18 to ≈4.65 eV varying with the numbers of layers is theoretically calculated and experimentally confirmed. 2D GaN with well-controlled lattice structure and bandgap holds great potential for the development of deep ultraviolet light-emitting diodes, energy conversion devices, etc.

10.
Adv Mater ; 31(2): e1803448, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30393921

RESUMEN

Due to the superior thickness-dependent properties, 2D materials have exhibited great potential for applications in next-generation optoelectronic devices. Despite the significant progress that has been achieved, the synthesis of 2D AlN remains challenging. This work reports on the epitaxial growth of 2D AlN layers via utilizing physically transferred graphene on Si substrates by metal-organic chemical vapor deposition. The 2D AlN layers sandwiched between graphene and Si substrates are confirmed by annular bright-field scanning transmission electron microscopy and the effect of hydrogenation on the formation of 2D AlN layers is clarified by theoretical calculations with first-principles calculations based on density functional theory. Moreover, the bandgap of as-grown 2D AlN layers is theoretically predicted to be ≈9.63 eV and is experimentally determined to be 9.20-9.60 eV. This ultrawide bandgap semiconductor shows great promise in deep-ultraviolet optoelectronic applications. These results are expected to support innovative and front-end development of optoelectronic devices.

11.
J Dent ; 75: 12-21, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29787782

RESUMEN

OBJECTIVES: To evaluate the desensitizing effect of toothpastes that contain ingredients that act against dentine hypersensitivity (DH) and to compare this effect with negative controls. SOURCES: Five databases were searched to identify relevant articles published up to November 27, 2017. STUDY SELECTION: Randomized controlled trials (RCTs) comparing desensitizing toothpastes with a toothpastes without desensitizing component in adult patients that suffer from DH were included. The risk of bias was assessed according to the Cochrane guidelines, and the quality of the evidence was evaluated using the GRADE tool. Inverse variance random-effects meta-analyses of standardized mean differences (SMD) and 95% confidence intervals (CIs) were calculated using RevMan 5.3 software. DATA: 53 RCTs with 4796 patients were finally included in the meta-analysis. The toothpastes that contain active desensitization ingredients showed a better desensitizing effect on DH than the negative control, except the strontium- and amorphous calcium phosphate-containing toothpastes. The amorphous calcium phosphate-containing toothpaste had very low-quality evidence, the strontium, potassium and strontium, and potassium and stannous fluoride-containing toothpastes had low-quality evidence, and the other five toothpastes had moderate quality evidence. CONCLUSIONS: Our result support the premise that toothpastes containing potassium, stannous fluoride, potassium and strontium, potassium and stannous fluoride, calcium sodium phosphosilicate, arginine, and nano-hydroxyapatite relieve the symptoms of DH, but does not advise the use of toothpastes that contain strontium and amorphous calcium phosphate. Furthermore, high-quality studies are needed to confirm our results. (PROSPERO CRD42018085639).


Asunto(s)
Desensibilizantes Dentinarios , Sensibilidad de la Dentina , Adulto , Fluoruros , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Estroncio , Fluoruros de Estaño , Pastas de Dientes
12.
Phys Chem Chem Phys ; 19(32): 21467-21473, 2017 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-28759081

RESUMEN

The polarity of GaN epitaxial films grown on LiGaO2(001) substrates by pulsed laser deposition has been well controlled. It is experimentally proved that the GaN epitaxial films grown on nitrided LiGaO2(001) substrates reveal Ga-polarity, while the GaN epitaxial films grown on non-nitrided LiGaO2(001) substrates show N-polarity. The growth mechanisms for these two cases are systematically studied by first-principles calculations based on density functional theory. Theoretical calculation presents that the adsorption of a Ga atom preferentially occurs at the center of three N atoms stacked on the nitrided LiGaO2(001) substrates, which leads to the formation of Ga-polarity GaN. Whereas the adsorption of a Ga atom preferentially deposits at the top of a N atom stacked on the non-nitrided LiGaO2(001) substrates, which results in the formation of N-polarity GaN. This work of controlling the polarity of GaN epitaxial films is of paramount importance for the fabrication of group-III nitride devices for various applications.

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