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1.
Int J Mol Sci ; 23(13)2022 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-35805943

RESUMEN

This study aimed to induce bone-like tissue from immature muscular tissue (IMT) in vitro using commercially available recombinant human bone morphogenetic protein (rhBMP)-2, rhBMP-4, and rhBMP-7, and then implanting this tissue into a calvarial defect in rats to assess healing. IMTs were extracted from 20-day-old Sprague-Dawley (SD) fetal rats, placed on expanded polytetrafluoroethylene (ePTFE) with 10 ng/µL each of rhBMP-2, BMP-4, and BMP-7, and cultured for two weeks. The specimens were implanted into calvarial defects in 3-week-old SD rats for up to three weeks. Relatively strong radiopacity was observed on micro-CT two weeks after culture, and bone-like tissue, comprising osteoblastic cells and osteoids, was partially observed by H&E staining. Calcium, phosphorus, and oxygen were detected in the extracellular matrix using an electron probe micro analyzer, and X-ray diffraction patterns and Fourier transform infrared spectroscopy spectra of the specimen were found to have typical apatite crystal peaks and spectra, respectively. Furthermore, partial strong radiopacity and ossification were confirmed one week after implantation, and a dominant novel bone was observed after two weeks in the defect site. Thus, rhBMP-2, BMP-4, and BMP-7 differentiated IMT into bone-like tissue in vitro, and this induced bone-like tissue has ossification potential and promotes the healing of calvarial defects. Our results suggest that IMT is an effective tissue source for bone tissue engineering.


Asunto(s)
Proteína Morfogenética Ósea 7 , Ingeniería de Tejidos , Animales , Proteína Morfogenética Ósea 2/farmacología , Proteína Morfogenética Ósea 7/farmacología , Regeneración Ósea , Osteogénesis , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/farmacología , Cráneo/diagnóstico por imagen , Factor de Crecimiento Transformador beta/farmacología
2.
Int J Mol Sci ; 22(22)2021 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-34830277

RESUMEN

BACKGROUND: We investigated and compared the osteogenic potential and bone regeneration capacities of dedifferentiated fat cells (DFAT cells) and adipose-derived stem cells (ASCs). METHOD: We isolated DFAT cells and ASCs from GFP mice. DFAT cells were established by a new culture method using a mesh culture instead of a ceiling culture. The isolated DFAT cells and ASCs were incubated in osteogenic medium, then alizarin red staining, alkaline phosphatase (ALP) assays, and RT-PCR (for RUNX2, osteopontin, DLX5, osterix, and osteocalcin) were performed to evaluate the osteoblastic differentiation ability of both cell types in vitro. In vivo, the DFAT cells and ASCs were incubated in osteogenic medium for four weeks and seeded on collagen composite scaffolds, then implanted subcutaneously into the backs of mice. We then performed hematoxylin and eosin staining and immunostaining for GFP and osteocalcin. RESULTS: The alizarin red-stained areas in DFAT cells showed weak calcification ability at two weeks, but high calcification ability at three weeks, similar to ASCs. The ALP levels of ASCs increased earlier than in DFAT cells and showed a significant difference (p < 0.05) at 6 and 9 days. The ALP levels of DFATs were higher than those of ASCs after 12 days. The expression levels of osteoblast marker genes (osterix and osteocalcin) of DFAT cells and ASCs were higher after osteogenic differentiation culture. CONCLUSION: DFAT cells are easily isolated from a small amount of adipose tissue and are readily expanded with high purity; thus, DFAT cells are applicable to many tissue-engineering strategies and cell-based therapies.


Asunto(s)
Adipocitos/citología , Adipocitos/trasplante , Tejido Adiposo/citología , Regeneración Ósea/genética , Técnicas de Cultivo de Célula/métodos , Desdiferenciación Celular/genética , Osteogénesis/genética , Trasplante de Células Madre/métodos , Células Madre/metabolismo , Adipocitos/metabolismo , Animales , Calcificación Fisiológica/genética , Diferenciación Celular/genética , Células Cultivadas , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Ratones , Ratones Transgénicos , Osteoblastos/citología , Osteoblastos/metabolismo , Ingeniería de Tejidos/métodos , Trasplante Autólogo/métodos
3.
J Craniofac Surg ; 26(7): e575-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26468825

RESUMEN

The definition of bisphosphonate-related osteonecrosis of the jaw (BRONJ) was recently broadened and it is now known as medication-related osteonecrosis of the jaw (MRONJ). To date, the management of MRONJ is controversial. Conservative treatment is recommended, but it is difficult to successfully treat stage 3 MRONJ. Administration of teriparatide for the MRONJ treatment has only been documented in independent case reports and there are few reports on men with MRONJ treated with teriparatide. An 81-year-old man was referred in May 2014 for treatment of an unhealed tooth extraction wound in the mandible. He took minodronic acid hydrate (1 mg/d orally) for 2 years because of osteoporosis cure. On clinical examination, soft tissue swelling in the left mandibular first molar region extended to the inferior border of the mandible with extraoral fistula. Computed tomography (CT) revealed osteolysis extending to the inferior border resulting in pathologic fracture of mandibular bone. Based on these findings, a diagnosis of stage 3 MRONJ was made. We performed conservative treatment, including amoxicillin, but his symptoms did not improve. He was then treated with once-weekly subcutaneous injection of teriparatide. Although teriparatide injections were started without antibiotics, after 1 week, swelling, erythema, and purulent discharge from the extraoral fistula increased rapidly. Therefore, we combined the once-weekly teriparatide injection with amoxicillin administration. Three months later, the osteonecrosis had healed and CT showed significant bone regeneration and healing of the mandibular pathologic fracture. In addition, the mandibular fistula showed healing and the intraoral fistula was covered with normal mucosa.


Asunto(s)
Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Osteonecrosis de los Maxilares Asociada a Difosfonatos/tratamiento farmacológico , Conservadores de la Densidad Ósea/uso terapéutico , Enfermedades Mandibulares/tratamiento farmacológico , Teriparatido/uso terapéutico , Anciano de 80 o más Años , Conservadores de la Densidad Ósea/administración & dosificación , Regeneración Ósea/efectos de los fármacos , Fístula Dental/tratamiento farmacológico , Difosfonatos/administración & dosificación , Fracturas Espontáneas/etiología , Humanos , Imidazoles/administración & dosificación , Masculino , Fracturas Mandibulares/etiología , Osteoporosis/tratamiento farmacológico , Cicatrización de Heridas/efectos de los fármacos
4.
Adv Sci (Weinh) ; 11(13): e2308270, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38268432

RESUMEN

Some rodlike organic molecules exhibit exceptionally high layered crystallinity when composed of a link between π-conjugated backbone (head) and alkyl chain (tail). These molecules are aligned side-by-side unidirectionally to form self-organized polar monomolecular layers, providing promising 2D materials and devices. However, their interlayer stacking arrangements have never been tunable, preventing the unidirectional arrangements of molecules in whole crystals. Here, it is demonstrated that polar/antipolar interlayer stacking can be systematically controlled by the alkyl carbon number n, when the molecules are designed to involve effectively weakened head-to-head affinity. They exhibit remarkable odd-even effect in the interlayer stacking: alternating head-to-head and tail-to-tail (antipolar) arrangement in odd-n crystals, and uniform head-to-tail (polar) arrangement in even-n crystals. The films show excellent field-effect transistor characteristics presenting unique polar/antipolar dependence and considerably improved subthreshold swing in the polar films. Additionally, the polar films present enhanced second-order nonlinear optical response along normal to the film plane. These findings are key for creating polarity-controlled optoelectronic materials and devices.

5.
Dent Mater J ; 42(3): 383-389, 2023 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-36740258

RESUMEN

This study examined the crystal orientation of four kinds of pressable lithium disilicate glass-ceramics and evaluated the effect of crystal orientation on flexural strength. Bar-shaped (24 mm in length, 1.2 mm in thickness, 4.0 mm in width), disk-shaped (12 mm in diameter, 0.5 mm in thickness), and crown-shaped (maxillary first molar) specimens were prepared according to the manufacturer's instructions. Three-point and biaxial flexural strengths were measured for bar- and disk-shaped specimens. Microstructure analysis was performed using X-ray diffractometry and scanning electron microscopy. Three-point flexural strength was improved by parallel crystal orientation along the longitudinal direction of the bar-shaped specimen. There was no relationship between two-dimensional crystal orientation and biaxial flexural strength. The results of this study assumed that biaxial flexural strength was improved by the crystal orientation in the cross-sectional direction. Pressed restorations are expected to possess higher strength than milled restorations due to their crystal orientation.


Asunto(s)
Porcelana Dental , Resistencia Flexional , Estudios Transversales , Ensayo de Materiales , Porcelana Dental/química , Cerámica/química , Propiedades de Superficie
6.
Polymers (Basel) ; 15(16)2023 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-37631453

RESUMEN

This study evaluated the bonding characteristics of a silane coupling agent (SCA) and a methyl methacrylate (MMA)-containing primer (MCP) for 11 types of commercial composite blocks (CBs) for sandblasted and non-sandblasted surfaces. The shear bond strength (SBS) was measured according to ISO 29022: Notched-edge shear bond strength test. The SBS results demonstrated statistically significant differences between the CBs under all identical conditions. For the non-sandblasted groups, the SBSs of MCP-treated specimens were significantly higher than those of SCA-treated specimens for all but two CBs. Comparing the two treatments in sandblasted groups, the SBS was significantly higher for seven out of 11 MCP-treated RCB specimens, in contrast with three cases for the SCA-treated group. Two-way ANOVA for SBS showed the interaction effect between sandblasting and primer type for specific CBs, indicating that the sandblasting treatment improved SBS more effectively for SCA-treated specimens. Moreover, the effect of the SCA treatment was more material-dependent compared to that of the MCP treatment, which did not achieve a strong bond in all CBs but proved more effective than the SCA treatment, especially for non-sandblasted surfaces.

7.
Nat Commun ; 13(1): 6708, 2022 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-36344506

RESUMEN

Future spintronics and quantum technologies will require a portfolio of techniques for manipulating electron spins in functional nanodevices. Especially, the establishment of the methods to control spin current is the key ingredient essential for the transfer and processing of information, enabling faster and low-energy operation. However, a universal method for manipulating spin currents with full-directional controllability and tunable magnitude has not been established. Here we show that an artificial material called a magnetic metamaterial (MM), which possesses a novel spintronic functionality not exhibited by the original substance, generates photo-driven ultrafast spin currents at room temperature via the magneto-photogalvanic effect. By tuning the polarization state of the excitation light, these spin currents can be directed with tunable magnitude along an arbitrary direction in the two-dimensional plane of the MM. This new concept may guide the design and creation of artificially engineered opto-spintronic functionalities beyond the limitations of conventional material science.

8.
Adv Mater ; 33(17): e2008611, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33754374

RESUMEN

The control of the optoelectronic properties of 2D organic-inorganic hybrid perovskite (2D-OIHP) lead halides is an increasingly prevalent topic. Herein, the observation of the circular photogalvanic effect (CPGE) in new enantiomorphic 2D-OIHP lead iodides is reported, which are synthesized as a first OIHP-related system belonging to a chiral space group by incorporating organic chiral cations into the inorganic layers of lead iodides. The CPGE is an optoelectronic phenomenon associated with the spin-orbit coupling of heavy atoms in noncentrosymmetric systems. Owing to the CPGE, light-helicity-dependent steady photocurrents are generated without an external bias voltage under the irradiation of circularly polarized light. Furthermore, the sign reversal of the CPGE photocurrent depending on the chirality of the designed 2D-OIHP lead iodides is observed. This result indicates formation of the theoretically predicted radial spin-polarized texture in k-space of chiral systems owing to spin-momentum locking. Hence, chiral 2D-OIHP lead halides can be a promising platform for engineering opto-spintronic functionalities.

9.
Eur J Oral Sci ; 117(5): 506-10, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19758245

RESUMEN

Sjögren's syndrome is a common systemic autoimmune disease associated with inflammatory cells that infiltrate exocrine glands. The antimicrobial peptides human beta-defensin-1, human beta-defensin-2, and human beta-defensin-3 are expressed in various human epithelial cells and in normal salivary glands. Antimicrobial peptides provide local protection against infection and participate in inflammatory responses. Because of the presence of inflammation, we hypothesized that human beta-defensin expression in minor salivary glands may be increased in subjects with Sjögren's syndrome. However, the expression of human beta-defensins 1 and 2 was decreased in salivary glands affected by Sjögren's syndrome in comparison with the human beta-defensin expression patterns in salivary glands from normal subjects. In addition, the reduction in expression of human beta-defensin-2 was greater than the reduction in expression of human beta-defensin-1. The aforementioned result suggests that the reduction in expression of human beta-defensin-2 may occur earlier than the reduction in expression of human beta-defensin-1, which may lead to a greater decrease in human beta-defensin-2 than in human beta-defensin-1 during disease progression.


Asunto(s)
Glándulas Salivales Menores/patología , Síndrome de Sjögren/patología , beta-Defensinas/análisis , Artritis Reumatoide/complicaciones , Progresión de la Enfermedad , Células Epiteliales/patología , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Saliva/metabolismo , Conductos Salivales/patología , Glándulas Salivales Menores/metabolismo , Tasa de Secreción/fisiología , Síndrome de Sjögren/clasificación , Síndrome de Sjögren/fisiopatología
10.
Mol Clin Oncol ; 7(5): 833-836, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29181174

RESUMEN

Platinum-based chemotherapy plus cetuximab represents the first-line treatment for recurrent or metastatic squamous cell carcinoma of the head and neck. The most common adverse events associated with cetuximab are infusion reactions and skin reactions, and a risk of venous thromboembolic events has also recently been reported in association with cetuximab. It is well known that thrombosis is a common complication of malignancy, and represents the second most frequent cause of mortality in cancer patients. The present study reports the case of a 79-year-old man who presented with lung and liver metastases from tongue squamous cell carcinoma, for which platinum-based chemotherapy plus cetuximab was administered. After 1 cycle, the patient showed rapid growth of a left ventricular (LV) thrombus, despite ongoing antiplatelet therapy for an old myocardial infarction. Anticoagulant therapy was administered to treat the LV thrombus, which resolved within 1 week. To the best of our knowledge, this represents the first reported case of rapidly occurring LV thrombus associated with platinum-based chemotherapy plus cetuximab. Platinum-based chemotherapy plus cetuximab may be associated with a higher risk of embolic thrombus.

11.
J Dent Sci ; 12(4): 333-339, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30895072

RESUMEN

BACKGROUND/PURPOSE: Few studies have investigated the possibility that bisphosphonate-related osteonecrosis of the jaw (BRONJ) might reflect an immune response; however, gamma delta T cells have been shown to significantly decline in the blood of BRONJ patients. Additionally, there have been some reports of teriparatide usage for the treatment of BRONJ. In this study, we compared the effects of zoledronate and teriparatide on lymphocyte populations and inflammatory cytokine production in mice. MATERIALS AND METHODS: Thirty female ICR mice were divided into three groups (n = 10 each): a vehicle, a zoledronate, and a teriparatide group. Drugs were administered for 8 weeks in each group. Lymphocytes in the blood and thymus were analyzed and femurs were used for histological observation and lymphocytes analysis of bone marrow. Cytokines were measured in separated serum using Milliplex® multiplex immunoassay analysis. RESULTS: Zoledronate decreased the T cell number in the bone marrow. Additionally, serum levels of interleukin (IL)-2, IL-7, IL-12, IL-15 and RANTES, which are cytokines that affect T cell activation, differentiation and/or proliferation, were significantly lower in zoledronate treated mice. Conversely, teriparatide treatment induced an increase in gamma delta T cells in peripheral blood. CONCLUSION: Gamma delta T cells in the bone marrow are expected to decrease with zoledronate treatment and increase with teriparatide treatment. If BRONJ involves a loss of gamma delta T cells in the circulation or bone marrow, then the increase in gamma delta T cells that is induced by teriparatide may account for its ability to resolve BRONJ.

12.
J Surg Case Rep ; 2016(2)2016 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-26872961

RESUMEN

We present a case of paediatric Stage IV sporadic Burkitt's leukaemia presenting as cheek enlargement with osteolysis of the maxilla. An 8-year-old boy was referred to our department with diffuse swelling of both cheeks. Head and neck examination revealed bilateral diffuse nontender swelling, non-fluctuant but slightly compressible. Computed tomography imaging showed enhancing bilateral bulky lesions expanding the maxillary sinuses, with associated osteolysis in the posterior walls of both sinuses. Laboratory results included blast cells in the peripheral blood, suggesting a haematopoietic tumour. We referred the patient to the Department of Paediatric Haematology and Oncology. Additional examinations eventually led to the diagnosis of Stage IV sporadic Burkitt's leukaemia.

13.
Science ; 348(6239): 1112-5, 2015 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-26045431

RESUMEN

The manipulation of domains by external fields in ferroic materials is of major interest for applications. In multiferroics with strongly coupled magnetic and electric order, however, the magnetoelectric coupling on the level of the domains is largely unexplored. We investigated the field-induced domain dynamics of TbMnO3 in the multiferroic ground state and across a first-order spin-flop transition. In spite of the discontinuous nature of this transition, the reorientation of the order parameters is deterministic and preserves the multiferroic domain pattern. Landau-Lifshitz-Gilbert simulations reveal that this behavior is intrinsic. Such magnetoelectric correlations in spin-driven ferroelectrics may lead to domain wall-based nanoelectronics devices.

14.
Nat Commun ; 6: 6724, 2015 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-25832200

RESUMEN

Interest in manipulating the magnetic order by ultrashort laser pulses has thrived since it was observed that such pulses can be used to alter the magnetization on a sub-picosecond timescale. Usually this involves demagnetization by laser heating or, in rare cases, a transient increase of magnetization. Here we demonstrate a mechanism that allows the magnetic order of a material to be enhanced or attenuated at will. This is possible in systems simultaneously possessing a low, tunable density of conduction band carriers and a high density of magnetic moments. In such systems, the thermalization time can be set such that adiabatic processes dominate the photoinduced change of the magnetic order--the three-temperature model for interacting thermalized electron, spin and lattice reservoirs is bypassed. In ferromagnetic Eu(1-x)Gd(x)O, we thereby demonstrate the strengthening as well as the weakening of the magnetic order by ~10% and within ≤3 ps by optically controlling the magnetic exchange interaction.

15.
J Mol Histol ; 43(2): 223-33, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22203245

RESUMEN

Some progress has been made in development of methods to regenerate bone from cultured cells, however no method is put to practical use. Here, we developed methods to isolate, purify, and expand mesenchymal stem cells (MSCs) from mouse compact bone that may be used to regenerate bone in vivo. These cells were maintained in long-term culture and were capable of differentiating along multiple lineages, including chondrocyte, osteocyte, and adipocyte trajectories. We used standard cell isolation and culture methods to establish cell cultures from mouse compact bone and bone marrow. Cultures were grown in four distinct media to determine the optimal composition of culture medium for bone-derived MSCs. Putative MSCs were subjected to flow cytometry, alkaline phosphatase assays, immunohistochemical staining, and several differentiation assays to assess cell identity, protein expression, and developmental potential. Finally, we used an in vivo bone formation assay to determine whether putative MSCs were capable of regenerating bone. We found that compact bone of mice was a better source of MCSs than the bone marrow, that growth in plastic flasks served to purify MSCs from hematopoietic cells, and that MSCs grown in basic fibroblast growth factor (bFGF)-conditioned medium were, based on multiple criteria, superior to those grown in leukemia inhibitory factor-conditioned medium. Moreover, we found that the MSCs isolated from compact bone and grown in bFGF-conditioned medium were capable of supporting bone formation in vivo. The methods and results described here have implications for understanding MSC biology and for clinical purpose.


Asunto(s)
Adipocitos/citología , Huesos/citología , Condrocitos/citología , Factor 2 de Crecimiento de Fibroblastos/farmacología , Células Madre Mesenquimatosas/citología , Osteocitos/citología , Osteogénesis/efectos de los fármacos , Adipocitos/metabolismo , Animales , Células de la Médula Ósea/citología , Células de la Médula Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Separación Celular , Células Cultivadas , Condrocitos/metabolismo , Medios de Cultivo Condicionados , Citometría de Flujo , Células Madre Mesenquimatosas/efectos de los fármacos , Ratones , Ratones Transgénicos , Osteocitos/metabolismo , Osteogénesis/fisiología , Regeneración/efectos de los fármacos , Regeneración/fisiología , Ingeniería de Tejidos
16.
J Obstet Gynaecol Res ; 34(4 Pt 2): 649-52, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18840173

RESUMEN

Twin-reversed arterial perfusion (TRAP) sequence is a rare and compromised complication in monochorionic pregnancies. The retrograde blood flow through placental communicating vessels is mainly involved to develop the syndrome. Increased cardiac output in the pump twin can lead to severe clinical manifestations. Various surgical techniques to occlude vascular communications between the pump twin and acardiac twin have been reported. A woman with TRAP sequence, at 22 weeks of gestation, complicated with progressive polyhydramnios underwent fetoscopic laser photocoagualtion of vascular communications on the placental surface. Fetoscopic observation demonstrated one artery-to-artery anastomosis and one venous-to-venous anastomosis from the pump twin to the acardiac twin, and these communications were successfully photocoagulated. The patient delivered a 2308-g female infant at 34 weeks and 1 day of gestation, following premature rupture of membrane. The infant is now 1 year old without any neurological problem. Fetoscopic laser photocoagulation of placental communicating vessels can be the procedure of choice for TRAP sequence.


Asunto(s)
Transfusión Feto-Fetal/terapia , Coagulación con Láser , Placenta/cirugía , Adulto , Femenino , Corazón Fetal/anomalías , Transfusión Feto-Fetal/etiología , Fetoscopía , Humanos , Placenta/irrigación sanguínea , Embarazo , Resultado del Embarazo , Gemelos
17.
Int J Gynecol Pathol ; 24(3): 218-23, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15968195

RESUMEN

A case of primary retroperitoneal mucinous cystic tumor of borderline malignancy is reported. A 36-year-old, nulliparous woman complained of abdominal fullness. Physical examination revealed a cystic mass 12-cm x 8-cm in size. At laparotomy, a cystic tumor was observed in the right retroperitoneal space. Both ovaries appeared normal and the uterus was almost normal except for small myomatous nodules. Removal of the retroperitoneal tumor, an appendectomy, and a myomectomy were performed. The histologic diagnosis was a primary retroperitoneal mucinous cystic tumor of borderline malignancy, similar to findings for ovarian tumor. There was no evidence of disease 6 months after the surgery.


Asunto(s)
Cistoadenoma Mucinoso/patología , Neoplasias Retroperitoneales/patología , Adulto , Apendicectomía , Cistoadenoma Mucinoso/cirugía , Femenino , Histocitoquímica , Humanos , Neoplasias Retroperitoneales/cirugía
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