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1.
Antonie Van Leeuwenhoek ; 117(1): 27, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38261019

RESUMO

Microorganisms, including native yeasts, are abundant in vineyard fields. Herein, we studied the possibility of using vineyard-derived wild yeast as a microbial pesticide against Botrytis cinerea, a pathogen that causes grape gray mold disease, to boost the initial alcohol production of spontaneously fermented wine. We identified the Saccharomyces cerevisiae strain KONDO170908, which showed the most effective antifungal activity in an ex vivo yeast dripping experiment on grape berries. This strain was utilized in an in vivo spray test on grape bunches in vineyard fields and was proven to significantly suppress gray mold disease on the grape berries in test plot #16 when the yeast was sprayed during both the flowering and ripening periods (morbidity 11.2% against 15.3% of the control plot, χ2 test, p < 0.0001). However, in test plot #17, spraying the yeast during only the ripening period had no effect (morbidity 16.3%). The grapes from each test plot were also submitted for spontaneous wine fermentation. Alcoholic fermentation of the grapes from test plot #16 provided the most active bubbling of CO2 gas and the highest ethanol production and colony counts over seven days of fermentation. Unique changes in the different strains of S. cerevisiae among the plots were observed throughout the early fermentation stage. Thus, yeast spraying during the flowering period might trigger modification of the entire microbiota and could ultimately contribute to promoting alcohol production in the spontaneously fermented wine, although it decreased the grape yield by 20%.


Assuntos
Vitis , Vinho , Saccharomyces cerevisiae , Antifúngicos/farmacologia , Fazendas , Etanol
2.
Org Lett ; 25(22): 4193-4197, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37227424

RESUMO

A copper-catalyzed disilylative cyclization of silicon-containing internal alkynes with silylboronates has been developed for the synthesis of 3-silyl-1-silacyclopent-2-enes. The reaction proceeded regio- and anti-selectively under simple and mild conditions by employing a combination of nucleophilic silicon donors and electrophilic silicon acceptors. The reaction could also be extended to the synthesis of a 1-germacyclopent-2-ene and a silicon-centered spirocyclic compound by using appropriate alkyne substrates.


Assuntos
Cobre , Silício , Silício/química , Cobre/química , Alcinos/química , Catálise , Ciclização
3.
J Phys Chem A ; 126(32): 5483-5491, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35925805

RESUMO

Optical imaging of individual single-walled carbon nanotubes (SWCNTs) enables the characterization of heterogeneous SWCNT samples. However, previous measurement methods have targeted SWCNTs fixed on a substrate. In this study, absorption-contrast imaging of individual SWCNTs moving irregularly in a solvent was performed by simultaneous multiwavelength photothermal (PT) microscopy. Using this technique, heterogeneous samples containing semiconducting and metallic SWCNTs were characterized by absorption spectroscopy. The semiconducting and metallic SWCNTs were visualized in different colors in the obtained multiwavelength images due to their different absorption spectra. Statistical analysis of the multiwavelength signals revealed that semiconducting and metallic SWCNTs could be distinguished with more than 90% accuracy. Time-series PT imaging of the nanotube aggregates induced by salt addition was also conducted by performing single-nanotube measurements. Our study demonstrated that PT microscopy is a versatile technique for determining the composition and degree of aggregation of SWCNTs in liquid and polymeric media, which can promote the industrial application of such materials.

4.
Org Biomol Chem ; 19(27): 6038-6044, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-33982042

RESUMO

Cynaropicrin is found in artichoke (Cynara scolymus) and is the source of its bitter taste and it is a sesquiterpene lactone with a 5-7-5 tricyclic skeleton, six chiral centers, and four exo-olefins. This natural product has numerous attractive biological activities including the inhibition of NF-κB activation, antihepatitis C activity, and antitrypanosomal activity. In this study, the first total synthesis of cynaropicrin was achieved starting from (S)-α-pinene. The synthesis involved a stereoselective Favorskii rearrangement and an indium-promoted diastereoselective Barbier reaction.

5.
Int J Comput Assist Radiol Surg ; 15(12): 1989-1995, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33009985

RESUMO

PURPOSE: The main purpose of this study is to construct a system to track the tumor position during radiofrequency ablation (RFA) treatment. Existing tumor tracking systems are designed to track a tumor in a two-dimensional (2D) ultrasound (US) image. As a result, the three-dimensional (3D) motion of the organs cannot be accommodated and the ablation area may be lost. In this study, we propose a method for estimating the 3D movement of the liver as a preliminary system for tumor tracking. Additionally, in current 3D movement estimation systems, the motion of different structures during RFA could reduce the tumor visibility in US images. Therefore, we also aim to improve the estimation of the 3D movement of the liver by improving the liver segmentation. We propose a novel approach to estimate the relative 6-axial movement (x, y, z, roll, pitch, and yaw) between the liver and the US probe in order to estimate the overall movement of the liver. METHOD: We used a convolutional neural network (CNN) to estimate the 3D displacement from two-dimensional US images. In addition, to improve the accuracy of the estimation, we introduced a segmentation map of the liver region as the input for the regression network. Specifically, we improved the extraction accuracy of the liver region by using a bi-directional convolutional LSTM U-Net with densely connected convolutions (BCDU-Net). RESULTS: By using BCDU-Net, the accuracy of the segmentation was dramatically improved, and as a result, the accuracy of the movement estimation was also improved. The mean absolute error for the out-of-plane direction was 0.0645 mm/frame. CONCLUSION: The experimental results show the effectiveness of our novel method to identify the movement of the liver by BCDU-Net and CNN. Precise segmentation of the liver by BCDU-Net also contributes to enhancing the performance of the liver movement estimation.


Assuntos
Aprendizado Profundo , Processamento de Imagem Assistida por Computador/métodos , Fígado/diagnóstico por imagem , Redes Neurais de Computação , Movimentos dos Órgãos/fisiologia , Ultrassonografia/métodos , Humanos , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/cirurgia , Ablação por Radiofrequência
6.
J Forensic Sci ; 65(5): 1474-1479, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32539170

RESUMO

In this study, the nondestructive differentiation of individual white polyester clothing fibers was accomplished via synchrotron radiation microbeam X-ray fluorescence (SR-µ-XRF) analysis. SR-µ-XRF with vertical focusing is a useful nondestructive method for the analysis of a single polyester clothing fiber. Kirkpatrick-Baez (KB) mirror was used to vertically focus 20 keV X-rays for the analysis of 22 individual white polyester fibers taken from clothing commonly sold in Japan. SR-µ-XRF with a vertical focused 2 µm (V) × 300 µm (H) beam was approximately 12.8 times more sensitive than SR-XRF with an unfocused 300 µm (V) × 300 µm (H) beam for the detection of elements in single fibers. The minimum detection limits (MDLs) of the SR-µ-XRF method were 8.15 ppm for Cl and 0.06 ppm for Br. In addition to Ti in TiO2 delustering agents, Zr and Nb impurities in the delustering agents were detected in individual fibers. Sb from a polymerization catalyst and Co from a transesterification catalyst were also detected in individual fibers. Comparing the Ti Kß /Sb Lα,ß and Zr Kα /Nb Kα X-ray intensity ratios was a useful way to distinguish individual clothing fibers, and 98% of the fibers were differentiated when additional trace elements were used as discrimination indicators.

7.
J Clin Med ; 8(10)2019 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-31569492

RESUMO

We previously reported that CaCl2 hydrothermal-treated (Ca-HT) titanium (Ti) implants induced a tight sealing at the interface between the implant and peri-implant epithelium (PIE) after implantation. However, it is not clear how long this improved epithelium sealing can be maintained. We subsequently investigated whether the positive effect of Ca-HT to promote sealing between the PIE and implant was sustained longer term. Maxillary molars were extracted from rats and replaced with either Ca-HT implants (Ca-HT group), distilled water-HT implants (DW-HT group) or non-treated implants (control group). After 16 weeks, the majority of implants in the Ca-HT group remained at the maxillary with no apical extension of the PIE. Conversely, half the number of control implants was lost following down-growth of the PIE. The effect of Ca-HT on migration and proliferation of rat oral epithelial cells (OECs) was also investigated. In OECs cultured on Ca-HT Ti plates, protein expression in relation to cell migration decreased, and proliferation was higher than other groups. Surface analysis indicated HT enhanced the formation of surface TiO2 layer without altering surface topography. Consequently, Ca-HT of Ti reduced PIE down-growth via tight epithelial attachment to the surface, which may enhance implant capability for a longer time post-implantation.

8.
J Biomed Mater Res A ; 107(7): 1379-1385, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30724473

RESUMO

The aims of implant treatment now involve not only restoration of mastication function, but also recovery of esthetics. Currently, zirconia is widely used as an esthetic material for implant abutment. Therefore, it is very important to understand the efficacy of zirconia for epithelial sealing as an implant material. We compared the effects of materials on the sealing of the peri-implant epithelium (PIE) to titanium (Ti) or zirconia (Zr) implants, for application to clinical work. Maxillary first molars were extracted from rats and replaced with Ti or Zr implants. The sealing of the PIE to the implants was evaluated with immunohistochemistry observation and HRP analysis. The morphological and functional changes in rat oral epithelial cells (OECs) cultured on Ti or Zr plates were also evaluated. After 4 weeks, the PIE on the Ti and Zr implants showed similar structures. The Zr implants appeared to form a weak epithelial seal at the tissue-implant interface, and exhibited markedly less adhesive structures than the Ti implants under electron microscopic observation. In the in vitro experiments, decreased expression levels of adhesion proteins were observed in OECs cultured on Zr plates compared with those cultured on Ti plates. In addition, the cell adherence on Zr plates was reduced, while the cell migration was low on Ti plates. Zr is a better choice for an esthetic implant material, but needs further improvement for integration with the epithelial wound healing process around a dental implant. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019.


Assuntos
Células Epiteliais/efeitos dos fármacos , Implantes Experimentais , Titânio/farmacologia , Zircônio/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/ultraestrutura , Peroxidase do Rábano Silvestre/metabolismo , Masculino , Boca/citologia , Fenótipo , Ratos Wistar
9.
Int J Implant Dent ; 4(1): 2, 2018 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-29332154

RESUMO

BACKGROUND: Multipotent mesenchymal stem cells (MSCs) are used clinically in regenerative medicine. Our previous report showed systemically injected MSCs improved peri-implant sealing and accelerated tissue healing. However, the risks of systemic MSC administration, including lung embolism, must be considered; therefore, their local application must be assessed for clinical safety and efficacy. We investigated differences in treatment effect between local and systemic MSC application using a rat oral implantation model. METHODS: Rat bone marrow-derived MSCs were isolated and culture-expanded. The rat's right maxillary first molars were extracted and replaced with experimental titanium implants. After 24 h, MSCs (1 × 106/ml) were systemically or locally injected into recipient rats via the tail vein (systemic group) or buccal subcutaneous tissue (local group), respectively. Rats treated in the absence of MSCs were included as a control (control group). The maxillary epithelium was assessed histologically after 4 weeks to evaluate laminin-332 (Ln-332) distribution and horseradish peroxidase invasion, as indicators of peri-implant epithelium (PIE) formation and PIE sealing to the implant surface, respectively. The effect of MSCs on rat oral epithelial cell (OEC) morphology was determined by coculture. RESULTS: Systemic group MSCs accumulated early at the peri-implant mucosa, while local group MSCs were observed in various organs prior to later accumulation around the implant surface. PIE formation and Ln-332-positive staining at the implant interface were enhanced in the systemic group compared with the local and control groups. Furthermore, OEC adherence on implants was reduced in high-density compared with low-density MSC cocultures. CONCLUSIONS: Local MSC injection was more ineffective than systemic MSC injection at enhancing PIE sealing around titanium implants. Thus, although local MSC administration has a wide range of applications, further investigations are needed to understand the exact cellular and molecular mechanisms of this approach prior to clinical use.

10.
Stem Cell Res Ther ; 7(1): 119, 2016 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-27530108

RESUMO

BACKGROUND: Mesenchymal stem cells (MSCs) have been isolated from a variety of tissues, including bone marrow, adipose, and mucosa. MSCs have the capacity for self-renewal and differentiation. Reports have been published on the systemic administration of MSCs leading to functional improvements by engraftment and differentiation, thus providing a new strategy to regenerate damaged tissues. Recently, it has become clear that MSCs possess immunomodulatory properties and can therefore be used to treat diseases. However, the therapeutic effect mechanisms of MSCs are yet to be determined. Here, we investigated these mechanisms using a medication-related osteonecrosis of the jaw (MRONJ)-like mouse model. METHODS: To generate MRONJ-like characteristics, mice received intravenous zoledronate and dexamethasone two times a week. At 1 week after intravenous injection, maxillary first molars were extracted, and at 1 week after tooth extraction, MSCs were isolated from the bone marrow of the mice femurs and tibias. To compare "diseased MSCs" from MRONJ-like mice (d-MSCs) with "control MSCs" from untreated mice (c-MSCs), the isolated MSCs were analyzed by differentiation and colony-forming unit-fibroblast (CFU-F) assays and systemic transplantation of either d-MSCs or c-MSCs into MRONJ-like mice. Furthermore, we observed the exchange of cell contents among d-MSCs and c-MSCs during coculture with all combinations of each MSC type. RESULTS: d-MSCs were inferior to c-MSCs in differentiation and CFU-F assays. Moreover, the d-MSC-treated group did not show earlier healing in MRONJ-like mice. In cocultures with any combination, MSC pairs formed cell-cell contacts and exchanged cell contents. Interestingly, the exchange among c-MSCs and d-MSCs was more frequently observed than other pairs, and d-MSCs were distinguishable from c-MSCs. CONCLUSIONS: The interaction of c-MSCs and d-MSCs, including exchange of cell contents, contributes to the treatment potential of d-MSCs. This cellular behavior might be one therapeutic mechanism used by MSCs for MRONJ.


Assuntos
Arcada Osseodentária/citologia , Células-Tronco Mesenquimais/citologia , Osteonecrose/terapia , Células-Tronco/citologia , Cicatrização/fisiologia , Animais , Células da Medula Óssea/citologia , Diferenciação Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura/métodos , Ensaio de Unidades Formadoras de Colônias/métodos , Fibroblastos/citologia , Masculino , Transplante de Células-Tronco Mesenquimais/métodos , Camundongos , Camundongos Endogâmicos C57BL
11.
J Prosthodont Res ; 60(1): 3-11, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26725967

RESUMO

PURPOSE: The aim of this study was to provide an overview on the biology and soft tissue sealing around dental implants and teeth. STUDY SELECTION: This is a narrative review performed through scientific articles published between 1977 and 2014, indexed in MEDLINE and PubMed databases. The study selected articles that focused on epithelial sealing around dental implant or teeth with cell biology and histology of soft tissue. RESULTS: Implant therapy has been widely applied in dental rehabilitation for many years, with predictable long-term results. The longevity and functionality of dental implants is dependent on both osseointegration around the implant body and the establishment of a soft tissue barrier that protects the underlying hard tissue structures and the implant itself. The health and stability of the peri-implant mucosa also affects the esthetics of the implant. The healing and maintenance of the epithelial and connective tissues around implants are increasingly recognized as being fundamental to implant success. However, there has been little research into the function or formation of the soft tissue seal around dental implants, and the roles of this unique mucosal interface remain unclear. CONCLUSIONS: This narrative review explores the extent of the current knowledge of soft tissue barriers around implants from both a basic and clinical perspective, and aims to consolidate this knowledge and highlight the most pertinent questions relating to this area of research.


Assuntos
Tecido Conjuntivo , Implantação Dentária/métodos , Implantes Dentários , Tecido Conjuntivo/patologia , Tecido Conjuntivo/fisiologia , Células do Tecido Conjuntivo , Epitélio , Gengiva , Humanos , Osseointegração , Dente
12.
Colloids Surf B Biointerfaces ; 131: 141-7, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25982317

RESUMO

Improvement of oral epithelial adhesion to titanium (Ti) may significantly enhance the efficacy of dental implants. We aimed to investigate whether calcium chloride (CaCl2) hydrothermally treated (HT) Ti could promote sealing of the peri-implant epithelium (PIE) around the implant. Right maxillary first molars were extracted from rats and replaced with either CaCl2-HT implants (Ca-HT group), distilled water-HT implants (DW-HT group), or untreated implants (Cont group). After 4 weeks, the implant-PIE interface of the Ca-HT group exhibited a band of immunoreactive laminin-332, similar to the tooth-junctional epithelium interface, which was absent in the Cont and DW-HT groups at the upper portion. We also investigated the effect of Ca-HT on the attachment of rat oral epithelial cells (OECs). OEC adherence onto Ca-HT Ti plates was stronger with higher expression levels of adhesion proteins compared with Cont and DW-HT groups. These results indicate that HT with CaCl2 improves the integration of soft tissue cells with the Ti implant at 4 weeks after implantation, which might facilitate the development of a soft tissue barrier around the implant.


Assuntos
Cloreto de Cálcio/farmacologia , Implantes Dentários , Células Epiteliais/efeitos dos fármacos , Titânio/química , Animais , Western Blotting , Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Células Epiteliais/metabolismo , Imuno-Histoquímica , Implantes Experimentais , Integrina beta4/metabolismo , Masculino , Plectina/metabolismo , Ratos Wistar , Propriedades de Superfície/efeitos dos fármacos , Fatores de Tempo , Cicatrização/efeitos dos fármacos , Calinina
13.
PLoS One ; 9(3): e90681, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24651408

RESUMO

OBJECTIVES: The objective of this study was to investigate the effect of systemically transplanted mesenchymal stem cells (MSCs) on the peri-implant epithelial sealing around dental implants. MATERIALS AND METHODS: MSCs were isolated from bone marrow of donor rats and expanded in culture. After recipient rats received experimental titanium dental implants in the bone sockets after extraction of maxillary right first molars, donor rat MSCs were intravenously transplanted into the recipient rats. RESULTS: The injected MSCs were found in the oral mucosa surrounding the dental implants at 24 hours post-transplantation. MSC transplantation accelerated the formation of the peri-implant epithelium (PIE)-mediated mucosa sealing around the implants at an early stage after implantation. Subsequently, enhanced deposition of laminin-332 was found along the PIE-implant interface at 4 weeks after the replacement. We also observed enhanced attachment and proliferation of oral mucous epithelial cells. CONCLUSION: Systemically transplanted MSCs might play a critical role in reinforcing the epithelial sealing around dental implants.


Assuntos
Implantes Dentários , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Mucosa Bucal/citologia , Animais , Células da Medula Óssea/citologia , Moléculas de Adesão Celular , Diferenciação Celular , Separação Celular , Técnicas de Cocultura , Células Epiteliais/citologia , Proteínas de Fluorescência Verde/metabolismo , Masculino , Células-Tronco Multipotentes/citologia , Ratos Transgênicos , Ratos Wistar , Extração Dentária , Cicatrização , Calinina
14.
Bioorg Med Chem Lett ; 24(3): 794-8, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24433861

RESUMO

Cynaropicrin is a guaianolide sesquiterpene lactone with a 5-7-5 tricyclic skeleton, four exo-olefins, and two hydroxyl groups. Recently, it was found that the compound is a potent in vitro and in vivo inhibitor of the protozoan parasite Trypanosoma brucei, which causes human African trypanosomiasis (HAT; sleeping sickness). In this Letter, chemical derivatization of cynaropicrin and the structure-activity-relationship (SAR) study against T. brucei is described.


Assuntos
Lactonas/química , Lactonas/farmacologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Tripanossomicidas/química , Tripanossomicidas/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos , Concentração Inibidora 50 , Lactonas/síntese química , Estrutura Molecular , Sesquiterpenos/síntese química , Relação Estrutura-Atividade , Tripanossomicidas/síntese química
15.
Am J Orthod Dentofacial Orthop ; 137(3): 340-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20197170

RESUMO

INTRODUCTION: The aims of this study were to assess the peer assessment rating (PAR) index in relation to perceived treatment needs for maxillary protrusion in Japanese subjects and to investigate how perceived orthodontic treatment needs change with increased experience in dentistry and orthodontics. METHODS: The subjects were 155 persons (73 men, 82 women; mean age, 24.2 years; SD, 4.7 years) including dental students, residents, and orthodontists. We showed them casts from 10 patients with untreated maxillary protrusion and gave them a questionnaire with a 100-point visual analog scale (VAS), concerning their perceptions of orthodontic treatment needs. The PAR index was used for cast evaluation. RESULTS: The PAR index showed significant correlations with the VAS scores. On the casts evaluated with a PAR index below 17, there was no difference in VAS scores between the 3 groups; however, orthodontists perceived significantly greater treatment needs than did students and residents on casts with a PAR index of 18 or 19. The VAS scores were significantly increased when casts with a PAR index of more than 20 and overjet above 5.0 mm were evaluated. Orthodontists and residents perceived greater treatment needs than students on assessing occlusions with severe maxillary protrusion. CONCLUSIONS: The PAR index is clinically useful to evaluate malocclusion, and the perception of treatment needs was significantly greater when the maxillary protrusion cast had a PAR index of more than 20 and overjet above 5.0 mm. Perceived needs for orthodontic treatment for maxillary protrusion changed with increasing experience and skills in dentistry and orthodontics.


Assuntos
Competência Clínica/estatística & dados numéricos , Má Oclusão/diagnóstico , Avaliação das Necessidades/estatística & dados numéricos , Ortodontia Corretiva/estatística & dados numéricos , Revisão por Pares , Prognatismo/diagnóstico , Adulto , Inquéritos de Saúde Bucal , Odontólogos , Estética Dentária , Feminino , Humanos , Internato e Residência , Masculino , Má Oclusão/epidemiologia , Maxila/anormalidades , Variações Dependentes do Observador , Ortodontia/educação , Ortodontia/normas , Prognatismo/epidemiologia , Estudantes de Odontologia , Adulto Jovem
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