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1.
Artigo em Chinês | WPRIM | ID: wpr-939713

RESUMO

OBJECTIVE@#To investigate the safety and efficacy of a new proteasome inhibitor Ixazomib followed by autologous hematopoietic stem cell transplantation (AHSCT) in the treatment of POEMS syndrome.@*METHODS@#The clinical manifestations, diagnosis and treatment process and follow-up results of 4 patients with POEMS syndrome who were treated with Ixazomib-based regimen combined with AHSCT in Wuhan No.1 Hospital from February 2018 to July 2020 were analyzed retrospectively. All patients were male, aged from 37-54 years old, with varying degrees of peripheral neuropathy, organ enlargement (liver, spleen or lymph nodes), circulatory overload (peripheral edema and/or pleural effusion), osteosclerosis, endocrine diseases (thyroid, gonads, etc.), skin changes (pigmentation, hemangioma, white nails, etc.), M protein, papilledema and other clinical manifestations and characteristics at the time of initial treatment. Two patients were pathologically diagnosed as hyaline vascular Castleman disease by lymph node biopsy. Three patients underwent lumbar puncture examinations and all showed elevated cerebrospinal fluid protein. All patients received at least 2 cycles of sequential AHSCT after induction chemotherapy based on ixazomib. The follow-up time was 10-28 months, and the median follow-up time was 16 months.@*RESULTS@#All cases survived. The complications were controllable during the treatment. Moreover, the clinical symptoms related to the disease were improved to a certain extent after the treatment. The levels of vascular endothelial growth factor (VEGF) showed a gradual decline.@*CONCLUSION@#Ixazomib combined with AHSCT is safe and effective in the treatment of POEMS syndrome.


Assuntos
Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Compostos de Boro , Glicina/análogos & derivados , Transplante de Células-Tronco Hematopoéticas , Síndrome POEMS/terapia , Estudos Retrospectivos , Transplante Autólogo , Fator A de Crescimento do Endotélio Vascular
2.
Braz. J. Pharm. Sci. (Online) ; 58: e201052, 2022. graf
Artigo em Inglês | LILACS | ID: biblio-1420425

RESUMO

Abstract Epidemiological studies suggest that acute kidney injury has certain effect on myocardial function. In this study, for the first time, we tested a boron compound namely lithium tetraborate an act as an anti-oxidant and anti-inflammatory agent in ischemia-reperfusion injury. For this, we employed an in vivo rat model with kidney ischemia reperfusion injury to evaluate cardiac injury to clarify the mechanisms of lithium tetraborate. The evaluation of cardiac injury through kidney artery occlusion and reperfusion rat model indicated that lithium tetraborate could (1) reduce oxidative stress-induced endothelial dysfunction; (2) attenuate the inflammatory response of cardiac cells; and (3) alleviate the apoptosis and necrosis of myocytes. In summary, lithium tetraborate demonstrates significant therapeutic properties that contribute to the amelioration of cardiac damage, and it could be a promising candidate for future applications in myocardial dysfunction.


Assuntos
Animais , Masculino , Feminino , Ratos , Compostos de Boro/análise , Cardiotônicos , Traumatismo por Reperfusão/patologia , Cardiotônicos/antagonistas & inibidores , Anti-Inflamatórios/classificação , Antioxidantes/classificação
3.
São Paulo; s.n; s.n; 2017. 201p ilus, tab, graf.
Tese em Português | LILACS | ID: biblio-849475

RESUMO

Neste trabalho, avaliou-se o potencial do uso de oxidantes quirais em oxidações enantiosseletivas de compostos orgânicos de boro. É de conhecimento geral que compostos orgânicos de boro, especialmente ésteres e ácidos borônicos são facilmente oxidados por hidroperóxidos em meio básico. No entanto, são escassos na literatura exemplos destas reações de modo enantiosseletivo. A fim de realizar as reações mencionadas, sintetizou-se os hidroperóxidos quirais TADOOH ({(4R,5R)-5-[(hidroperoxidifenil)metil]-2,2-dimetil-1,3-dioxolan-4il}difenilmetanol) e o hidroperóxido quiral derivado de carboidrato, 2,3-dideoxi1-O-oxidanil-4,6-di-O-pivaloil-α-D-eritro-hex-2-enopiranose (di-O-PivOOH). Estes compostos apresentaram resultados interessantes na literatura em oxidações enantiosseletiva de sulfetos orgânicos, em epoxidações de alcenos e em oxidações de Baeyer-Villiger. Inicialmente o potencial oxidativo de ambos hidroperóxidos, bem como a seletividade destes, foi avaliado frente a diversos ésteres borônicos, sendo que somente o TADOOH apresentou resultados promissores. (Ver esquema no PDF) Observou-se uma melhor seletividade do TADOOH frente a ésteres borônicos que possuíam grupos carbonílicos em sua estrutura. Ao submeter o ß-boronil-éster, 3-fenil-3-(4,4,5,5-tetrametil-1,3,2-dioxaborolan-2-il)propanoato de etila, à oxidação com o TADOOH em THF utilizando NaOH como base, a -30°C por 1 hora, obteve-se o respectivo álcool com 40% de e.e. Cálculos de DFT para o estado de transição na oxidação dos ésteres borônicos com o TADOOH foram realizados em colaboração com o grupo do Prof. Dr. Ataualpa Albert Carmo Braga. Estes cálculos demonstraram que o estado de transição é estabilizado por uma ligação de hidrogênio não clássica entre o oxigênio da carbonila e umas das ligações C-H dos grupos fenila do TADOOH. Além dos estudos relatados, a reconhecida metodologia de Sharpless na epoxidação assimétrica de alcoóis alílicos foi adaptada para a oxidação enantiosseletiva de ésteres borônicos. Ao trocar o ligante derivado de éster tártarico, normalmente utilizado nas epoxidações de Sharpless, por (-)-efedrina observou-se uma moderada seletividade deste sistema frente ao pinacol l-fenietilboronato. Investigações mais detalhadas demonstraram que a presença do Ti(IV) não era necessária, sendo que a (-)efedrina era a responsável pela ativação e indução quiral nesta reação.


In this work, it was investigated the potential use of chiral oxidants in organic boron compound oxidation. It is known in the literature, that organic boron compounds can be easily oxidized by hydroperoxides. However, an enantioselective approach in literature is scarce. In order to perform these reactions, hydroperoxide TADOOH ({(4R,5R)-5[(hydroperoxydiphenyl)methyl]-2,2-dimethyl-l,3-dioxolan-4-yl}diphenylmethanol) and carbohydrate derived hydroperoxide, 2,3-dideoxy-1-O-oxidanyl-4,6-di-O-pivaloyl-α-D-erythro-hex-2-enopyranose (di-O-PivOOH), have been synthesized. These compounds showed interesting results in several enantioselective oxidations, as like, organic sulfides oxidation, alkenes epoxidation and Baeyer-Villiger oxidations. The oxidative potential of both hydroperoxides, as well as their selectivity, were evaluated against several boronic esters. Only TADOOH has shown promissing results for further studies. (See Scheme on PDF). Boronic esters containing a carbonyl moiety showed better selectivities with TADOOH, for example, the reaction of ß-boronyl-ester, ethyl 3-phenyl-3-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)propanoate, gave the correponding alcohol with 40% e.e. DFT calculations for the transition state in the oxidation of the boronic esters with TADOOH were carried out in collaboration with the group of Prof. Dr. Ataualpa Albert Carmo Braga. These calculations have shown that the transition state is stabilized by a non-classical hydrogen bond between the carbonyl oxygen and one of the C-H bonds of the TADOOH phenyl groups. In addition to the studies, the well-known Sharpless protocol for asymmetric epoxidation of allylic alcohols was adapted in the enantioselective oxidation of boronic esters. By replacing the tartaric ester-derived, commonly used in the Sharpless experiments, for (-)-ephedrine moderate selectivity was observed with pinacol 1-phenylethyl boronate. Further investigations showed that the presence of Ti (IV) was not necessary, and (-)-ephedrine was responsible for the activation and chiral induction in this reaction.


Assuntos
Ésteres , Compostos Orgânicos , Oxidantes/síntese química , Compostos de Boro/química , Cinética
4.
Artigo em Coreano | WPRIM | ID: wpr-56595

RESUMO

PURPOSE: The purpose of this study was to evaluate the effect of surface treatment on the shear bond strength of zirconia ceramic to 3 resin cements. MATERIALS AND METHODS: A total of 143 disk-shaped Zirconia blocks (HASS Co., Gangneung, Korea) were randomly divided into three treatment groups: (1) only 50 microm Al2O3 sandblasting, (2) 50 microm Al2O3 sandblast and zircona liner, (3) 50 microm Al2O3 sandblasting and Rocatec (3M ESPE, Seefeld, Germany). Bistite II (Tokuyama Dental Co., Japan), Panavia F (Kuraray Medical, Japan), and Superbond C&B (Sun Medical, Japan) were used to cement onto the zirconia. After 24h of storage in distilled water, shear bond strength was evaluated. High value group was re-tested after thermocycling at 5,000 cycles(5-55degreesC). Shear bond strength data were analyzed with one-way ANOVA, two-way ANOVA test and Post Hoc Test (alpha=.05). Shear bond strength data before and after thermocycling were analyzed with Independent sample T test (alpha=.05). RESULTS: Super-bond C&B treated with Rocatec showed the most high shear bond strength. Super-bond C&B groups resulted in significantly higher than other cement groups (P<.05). Rocatec groups resulted in significantly higher than other surface treatment groups (P<.05). Shear bond strength has increased in Panavia F treated with Zirconia liner (P<.05). After thermocycling, shear bond strength was increased in Super-bond C&B treated with Rocatec but decreased in other groups (P<.05). CONCLUSION: Super-bond C&B cement resulted the highest shear bond strength and Rocatec system enhanced the shear bond strength. After thermocycling, shear bond strength has decreased in most resin cements except Super-bond C&B treated with Rocatec.


Assuntos
Compostos de Boro , Cerâmica , Cimentos Dentários , Metacrilatos , Metilmetacrilatos , Cimentos de Resina , Resinas Sintéticas , Água , Zircônio
5.
Pakistan Journal of Pharmaceutical Sciences. 2013; 26 (3): 431-438
em Inglês | IMEMR | ID: emr-142600

RESUMO

TRPV3 ion channels mediate thermo-transduction, nociception, inflammation and dermatitis in mammals. TRPV1-4 proteins have been shown to have conserved cysteine-residues in the pore-forming regions. These residues participate in channel activation via S-nitrosylation of channel proteins. Camphor is a commonly used ligand for TRPV3 channels. Thus the knowledge about the potential binding/interacting site[s] for camphor will help to design effective and potent analgesic compounds. In an overlap-extension PCR method, following primer-pairs were used to mutate conserved cysteine-residues in the pore-region of TRPV3 channels; GATTGAGAATcCTCCAAGGACAAAAAGGAC, TRPV3-C612S-Fw and GTCCTTGGAGgACTTCTCAATCAGTCAGTGAGG, TRPV3-C612S-Rv primers pair. And for TRPV3-C619S: GGACTCcAGTTCCTATGGCCAGC, TRPV3-C619S-Fw and GCTGGCCATAgGAACTGGAGTCC, TRPV3-C619S-Rv respectively. All cDNA constructs were confirmed by DNA-sequencing and used to make cRNAs. Oocytes expressing mTRPV3-C619S and mTRPV3-C612S mutant channels were challenged with 2-APB [1 mM], camphor [10 mM] and dihydrocarveol [10 mM] either at -40 mV or +40 mV holding potentials in voltage-clamp experiments. Responses of both mutants to 2-APB were similar to wild-type mTRPV3. Interestingly, responses to camphor were totally lost in mTRPV3-C619S mutant, while responses to dihydrocarveol remained intact. In contrast mTRPV3-C612S displayed slightly altered [16 +/- 2% reduction] phenotype with respect to camphor sensitivity. It is concluded that pore-region cysteines play critical role in camphor sensitivity of TRPV3 ion channels


Assuntos
Animais , Cânfora/farmacologia , Compostos de Boro/farmacologia , Sequência de Aminoácidos , Sítios de Ligação , Xenopus , Cisteína/metabolismo , DNA Complementar/genética , Camundongos , Dados de Sequência Molecular , Monoterpenos/farmacologia
6.
Artigo em Inglês | WPRIM | ID: wpr-181917

RESUMO

PURPOSE: The aim of this study was to determine whether the push-out bond strengths between the radicular dentin and fiber reinforced-composite (FRC) posts with various resin cements decreased or not, according to the coronal, middle or apical level of the root. MATERIALS AND METHODS: FRC posts were cemented with one of five resin cement groups (RelyX Unicem: Uni, Contax with activator & LuxaCore-Dual: LuA, Contax & LuxaCore-Dual: Lu, Panavia F 2.0: PA, Super-Bond C&B: SB) into extracted human mandibular premolars. The roots were sliced into discs at the coronal, middle and apical levels. Push-out bond strength tests were performed with a universal testing machine at a crosshead speed of 0.5 mm/min, and the failure aspect was analyzed. RESULTS: There were no significant differences (P>.05) in the bond strengths of the different resin cements at the coronal level, but there were significant differences in the bond strengths at the middle and apical levels (P.05); all other groups had a significant decrease in bond strength at the middle or apical level (P<.05). The failure aspect was dominantly cohesive at the coronal level of all resin cements (P<.05), whereas it was dominantly adhesive at the apical level. CONCLUSION: All resin cement groups showed decreases in bond strengths at the middle or apical level except LuA and Uni.


Assuntos
Humanos , Adesivos , Dente Pré-Molar , Compostos de Boro , Colódio , Resinas Compostas , Cimentos Dentários , Dentina , Metacrilatos , Metilmetacrilatos , Cimentos de Resina
7.
Biocell ; 36(2): 73-81, Aug. 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-662144

RESUMO

After depletion of intracellular Ca2+ stores the capacitative response triggers an extracellular Ca2+ influx through store-operated channels (SOCs) which refills these stores. Our objective was to explore if human umbilical artery smooth muscle presented this response and if it was involved in the mechanism of serotonin- and histamine-induced contractions. Intracellular Ca2+ depletion by a Ca2+-free extracellular solution followed by Ca2+ readdition produced a contraction in artery rings which was inhibited by the blocker of Orai and TRPC channels 2-aminoethoxydiphenyl borate (2-APB), suggesting a capacitative response. In presence of 2-APB the magnitude of a second paired contraction by serotonin or histamine was significantly less than a first one, likely because 2-APB inhibited store refilling by capacitative Ca2+ entry. 2-APB inhibition of sarcoplasmic reticulum Ca2+ release was excluded because this blocker did not affect serotonin force development in a Ca2+-free solution. The PCR technique showed the presence of mRNAs for STIM proteins (1 and 2), for Orai proteins (1, 2 and 3) and for TRPC channels (subtypes 1, 3, 4 and 6) in the smooth muscle of the human umbilical artery. Hence, this artery presents a capacitative contractile response triggered by stimulation with physiological vasoconstrictors and expresses mRNAs for proteins and channels previously identified as SOCs.


Assuntos
Humanos , Compostos de Boro/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , RNA Mensageiro/genética , Artérias Umbilicais/efeitos dos fármacos , Capacitância Vascular/efeitos dos fármacos , Western Blotting , Células Cultivadas , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/química , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Cálcio/metabolismo , Agonistas dos Receptores Histamínicos/farmacologia , Histamina/farmacologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Músculo Liso/citologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Retículo Sarcoplasmático/efeitos dos fármacos , Retículo Sarcoplasmático/metabolismo , Agonistas do Receptor de Serotonina/farmacologia , Serotonina/farmacologia , Canais de Cátion TRPC/genética , Canais de Cátion TRPC/metabolismo , Artérias Umbilicais/citologia , Artérias Umbilicais/metabolismo
8.
Artigo em Inglês | WPRIM | ID: wpr-727561

RESUMO

The receptor activator of NF-kappaB ligand (RANKL) signal is an activator of tumor necrosis factor receptor-associated factor 6 (TRAF6), which leads to the activation of NF-kappaB and other signal transduction pathways essential for osteoclastogenesis, such as Ca2+ signaling. However, the intracellular levels of inositol 1,4,5-trisphosphate (IP3) and IP3-mediated cellular function of RANKL during osteoclastogenesis are not known. In the present study, we determined the levels of IP3 and evaluated IP3-mediated osteoclast differentiation and osteoclast activity by RANKL treatment of mouse leukemic macrophage cells (RAW 264.7) and mouse bone marrow-derived monocyte/macrophage precursor cells (BMMs). During osteoclastogenesis, the expression levels of Ca2+ signaling proteins such as IP3 receptors (IP3Rs), plasma membrane Ca2+ ATPase, and sarco/endoplasmic reticulum Ca2+ ATPase type2 did not change by RANKL treatment for up to 6 days in both cell types. At 24 h after RANKL treatment, a higher steady-state level of IP3 was observed in RAW264.7 cells transfected with green fluorescent protein (GFP)-tagged pleckstrin homology (PH) domains of phospholipase C (PLC) delta, a probe specifically detecting intracellular IP3 levels. In BMMs, the inhibition of PLC with U73122 [a specific inhibitor of phospholipase C (PLC)] and of IP3Rs with 2-aminoethoxydiphenyl borate (2APB; a non-specific inhibitor of IP3Rs) inhibited the generation of RANKL-induced multinucleated cells and decreased the bone-resorption rate in dentin slice, respectively. These results suggest that intracellular IP3 levels and the IP3-mediated signaling pathway play an important role in RANKL-induced osteoclastogenesis.


Assuntos
Animais , Camundongos , Proteínas Sanguíneas , Compostos de Boro , ATPases Transportadoras de Cálcio , Membrana Celular , Dentina , Estrenos , Inositol , Inositol 1,4,5-Trifosfato , Receptores de Inositol 1,4,5-Trifosfato , Macrófagos , NF-kappa B , Osteoclastos , Fosfoproteínas , Proteínas , Pirrolidinonas , Receptor Ativador de Fator Nuclear kappa-B , Retículo , Transdução de Sinais , Fator de Necrose Tumoral alfa , Fosfolipases Tipo C
9.
Artigo em Chinês | WPRIM | ID: wpr-271785

RESUMO

The present paper is aimed to discuss the influence of three different ways on modification of aluminum borate whiskers (AlBw) and on flexural properties of dental composite resins. In Group A, AlBw and silicon dioxide (SiO2) nanoparticles were thermally fused directly under certain processes. In Group B, Si-O network was formed on the surface of AlBw via the sol-gel process of tetraethoxysilane, then thermally fused with SiO2 nanoparticles to form AlBw-SiO2 compound as inorganic fillers. In Group C, SiO2 nanoparticles were repaired by sol-gel method of tetraethoxysilane under certain processes, and were deposited in the surface of AlBw. The mixtures were fused with high temperature sintering method. The effects of the surface morphology of AlBw with different ways were characterized by TEM and SEM. Then the mixtures were polymerized with resin matrix after surface siliconization and their flexural strength and Young's modulus were determined. SEM was used to examine specimen fracture surfaces. The results showed that the flexural properties of dental composite resins were significantly improved after whiskers were modified. Different methods produce different effects. Flexural strength of the Group A is (95.28 +/- 4.53) MPa. The results of TEM and SEM revealed that the aggregation was obvious between AlBw and SiO2 nanoparticles. Flexural strength of the Group B was (123.14 +/- 17.37) MPa. The results of TEM and SEM revealed that the dispersity was improved but SiO2 nanoparticles also reunited. AlBw were modified with nanometer-size SiO2 particles which were prepared by sol-gel method based on tetraethyl orthosioate (TEOS), the flexural properties of a new type of dental composite resins was (130.29 +/- 8.38) MPa. The results of TEM and SEM revealed that better dispersion between AlBw and SiO2 nanoparticles occurred. The SiO2 nanoparticles were fused and attached onto the surface of AlBw uniformly.


Assuntos
Resinas Acrílicas , Química , Compostos de Alumínio , Química , Compostos de Boro , Química , Resinas Compostas , Química , Módulo de Elasticidade , Elasticidade , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanopartículas , Química , Transição de Fase , Poliuretanos , Química , Silanos , Química , Dióxido de Silício , Química , Estresse Mecânico , Propriedades de Superfície
10.
Artigo em Chinês | WPRIM | ID: wpr-235096

RESUMO

<p><b>OBJECTIVE</b>To evaluate the marginal microleakage of porcelain-fused-to-metal crown using four different cements.</p><p><b>METHODS</b>Sixteen porcelain-fused-to-metal crowns were built and randomly divided into 4 group, luted onto standard prepared human forward molars using four different cements (glass ionomer cement, resin-modified glass ionomer cement, PanaviaF, Super-Bond C&B adhesive luting system). After temperature cycling test, all the crowns were then submerged in 2% fuchsin for 24 h. The marginal microleakage at tooth cement interfaces was observed using light stereomicroscopy and evaluated in classification index. The marginal microleakage grade of 4 groups were analyzed by SPSS 13.0.</p><p><b>RESULTS</b>The PanaviaF demonstrated the least marginal microleakage, Super-Bond C&B adhesive luting system, resin-modified glass ionomer cement showed an intermediate level of marginal microleakage, glass ionomer cement was associated with severe marginal microleakage (total, Chi2 = 157.60, P < 0.01; among the different groups, P<0.05).</p><p><b>CONCLUSION</b>Adhesive resin luting system which is the first selection in clinical is better than glass ionomer cement and is good at porcelain-fused-to-metal crown.</p>


Assuntos
Humanos , Compostos de Boro , Cimentação , Coroas , Cimentos Dentários , Infiltração Dentária , Adaptação Marginal Dentária , Porcelana Dentária , Cimentos de Ionômeros de Vidro , Metais , Metacrilatos , Metilmetacrilatos , Cimentos de Resina
11.
Braz. dent. j ; 22(5): 359-364, 2011. tab
Artigo em Inglês | LILACS | ID: lil-601834

RESUMO

This study investigated the effects of the cement type and the water storage time on the push-out bond strength of a glass fiber post. Glass fiber posts (Fibrekor, Jeneric Pentron) were luted to post spaces using a self-cured resin cement (C&B Cement [CB]), a glass ionomer cement (Ketac Cem [KC]) or a resin-modified glass ionomer cement (GC FujiCEM [FC]) according to the manufacturers’ instructions. For each luting agent, the specimens were exposed to one of the following water storage times (n=5): 1 day (T1), 7 days (T7), 90 days (T90) and 180 days (T180). Push-out tests were performed after the storage times. Control specimens were not exposed to water storage, but subjected to the push-out test 10 min after post cementation. Data (in MPa) were analyzed by Kruskal-Wallis and Dunn`s test (α=0.05). Cement type and water storage time had a significant effect (p<0.05) on the push-out bond strength. CB showed significantly higher values of retention (p<0.05) than KC and FC, irrespective of the water storage time. Water storage increased significantly the push-out bond strength in T7 and T90, regardless of the cement type (p<0.05). The results showed that fiber posts luted to post spaces with the self-cured resin cement exhibited the best bonding performance throughout the 180-day water storage period. All cements exhibited a tendency to increase the bond strength after 7 and 90 days of water storage, decreasing thereafter.


Este estudo investigou os efeitos do tipo de cimento e do tempo de armazenamento em água na resistência adesiva ao cisalhamento de pinos de fibra. Pinos de fibra de vidro (Fibrekor, JenericPentron) foram cimentados aos condutos radiculares usando o cimento resinoso autopolimerizável (C&B Cement [CB]), o cimento de ionômero de vidro (Ketac Cem [KC]) ou o cimento de ionômero de vidro modificado por resina (GC FujiCEM [FC]) de acordo com as instruções dos fabricantes. Para cada cimento, os espécimes foram expostos a um dos seguintes tempos de armazenamento em água (n=5): 1 dia (T1), 7 dias (T7), 90 dias (T90) e 180 dias (T180). Os testes de resistência adesiva ao cisalhamento foram realizados após os períodos de armazenamento. Os espécimes controles não foram expostos ao armazenamento em água, mas submetidos ao teste de resistência adesiva ao cisalhamento 10 min após a cimentação do pino. Os dados (MPa) foram analisados usando Kruskal-Wallis e teste de Dunn (α=0,05). O tipo de cimento e o tempo de armazenamento em água afetaram significantemente a resistência adesiva ao cisalhamento (p<0,05). CB apresentou valores de retenção significantemente superiores a KC e FC, independentemente do tempo de armazenamento em água. Esse, por sua vez, aumentou significantemente a resistência adesiva ao cisalhamento em T7 e T90, independentemente do tipo de cimento (p<0,05). Os resultados indicaram que os pinos de fibra cimentados aos condutos radiculares com o cimento resinoso autopolimerizável apresentou a melhor performance adesiva durante todo o período de armazenamento em água de 180 dias. Todos os cimentos apresentaram uma tendência a aumentar a resistência adesiva ao cisalhamento após 7 e 90 dias de armazenamento em água, diminuindo posteriormente.


Assuntos
Humanos , Colagem Dentária , Cimentos Dentários/química , Vidro/química , Técnica para Retentor Intrarradicular/instrumentação , Água/química , Absorção , Adsorção , Compostos de Boro/química , Resinas Compostas/química , Cimentos Dentários/classificação , Cavidade Pulpar/anatomia & histologia , Dentina/anatomia & histologia , Cimentos de Ionômeros de Vidro/química , Teste de Materiais , Óxido de Magnésio/química , Metacrilatos/química , Metilmetacrilatos/química , Cimento de Policarboxilato/química , Cimentos de Resina/química , Preparo de Canal Radicular/métodos , Estresse Mecânico , Fatores de Tempo , Óxido de Zinco/química
12.
Acta odontol. latinoam ; 23(3): 216-221, Dec. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-949664

RESUMO

The aim of this study was to evaluate the influence of eugenolcontaining endodontic sealers and luting strategy on the pull-out bond strength of glass fiber posts to dentin. Sixty-four bovine incisors were randomly assigned into two groups of 32 specimens each for obturation procedure with gutta-percha only, or with Pulp Canal Sealer EWT. Subsequently, the roots were prepared for the fiber post Reforpost and all specimens of each endodontic sealing procedure were allocated to four groups (n=8), according to the strategies for post cementation: A) Single Bond 2 and RelyX ARC; B) All Bond 2 and C&B cement; C) All Bond 2 and RelyX ARC; D) Single Bond 2 and C&B Cement. The posts were cemented immediately after the endodontic treatment. The pull-out test was performed at a cross-head speed of 0.5 mm/min in a universal testing machine (EMIC). Data (Kgf) were submitted to a two-way ANOVA and Tukey test (p ≤ 0.05). The eugenol-based sealer did not influence the pull-out bond strength of fiber posts regardless of the luting strategy. RelyX ARC showed higher bond strength than C&B Cement when used with Single Bond 2 adhesive system, when the eugenol-based sealer was present. All Bond 2, when associated to all cements studied, promoted similar bond strength, regardless of the eugenol-containing endodontic sealer. In conclusion, eugenolcontaining sealer did not influence the pull-out bond strength values of the resin luting systems for glass fiber post cementation. The bond system and resin cement association from the same manufacturer had similar bond strength values for dentin.


O objetivo desse estudo foi avaliar a influencia de cimentos endodonticos a base de eugenol e estrategia de cimentacao resinosa na resistencia a tracao de pinos de fibra de vidro a dentina. Sessenta e quatro incisivos bovinos foram aleatoriamente divididos em dois grupos com 32 especimes para cada procedimento de obturacao, com o cimento a base de eugenol Pulp Canal Sealer EWT ou somente com guta percha pela tecnica termoplastificada. Apos, realizou-se o prepare do conduto radicular para o pino de fibra Reforpost e posteriormente, as amostras de cada procedimento obturador foram separadas em quarto grupos (n=8), considerando as estrategias para cimentacao do pino: A) Adper Single Bond 2 e RelyX ARC; B) All Bond 2 e C&B cement; C) All Bond 2 e RelyX ARC; D) Adper Single Bond 2 e C&B Cement. Os pinos foram imediatamente cimentados apos o tratamento endodontico. Dessa maneira, o teste de pull-out foi realizado a uma velocidade de 0.5 mm/min em maquina de ensaio universal (EMIC DL2000). Os dados (Kgf) A analise estatistica foi realizada pelos testes ANOVA de dois fatores e teste de Tukey (p ≤ 0.05). O cimento endodontico contend eugenol nao influenciou a resistencia de uniao a tracao (pull-out) dos pinos de fibra, independente da estrategia de cimentacao. O RelyX ARC ofereceu maior resistencia de uniao do pino a dentina, comparado ao C&B Cement quanto utilizado com o Adper Single Bond 2, na presenca do cimento endodontico contendo eugenol. O All Bond 2 quando associado a todos os cimentos estudados promoveram uma resistencia de uniao semelhante, independente do conteudo de eugenol na cimentacao endodontica. Em conclusao, o cimento endodontico a base de eugenol nao influenciou na resistencia a tracao de pinos de fibra a dentina. A associacao de sistema adesivo e cimento resinoso do mesmo fabricante apresentou valores de resistencia de uniao semelhantes na cimentacao de pinos de fibra.


Assuntos
Animais , Bovinos , Materiais Restauradores do Canal Radicular/química , Técnica para Retentor Intrarradicular/instrumentação , Colagem Dentária , Cimentos de Resina/química , Dentina/ultraestrutura , Vidro/química , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Obturação do Canal Radicular , Estresse Mecânico , Teste de Materiais , Compostos de Boro/química , Eugenol/química , Distribuição Aleatória , Colagem Dentária/métodos , Cimentação/métodos , Adesivos Dentinários/química , Bis-Fenol A-Glicidil Metacrilato/química , Cimentos Dentários/química , Cavidade Pulpar/ultraestrutura , Análise do Estresse Dentário/instrumentação , Lâmpadas de Polimerização Dentária , Guta-Percha/química , Metacrilatos/química , Metilmetacrilatos/química
13.
Artigo em Inglês | WPRIM | ID: wpr-727334

RESUMO

Inositol 1,4,5-trisphosphate receptors (InsP3Rs) modulate Ca2+ release from intracellular Ca2+ store and are extensively expressed in the membrane of endoplasmic/sarcoplasmic reticulum and Golgi. Although caffeine and 2-aminoethoxydiphenyl borate (2-APB) have been widely used to block InsP3Rs, the use of these is limited due to their multiple actions. In the present study, we examined and compared the ability of caffeine and 2-APB as a blocker of Ca2+ release from intracellular Ca2+ stores and Ca2+ entry through store-operated Ca2+ (SOC) channel in the mouse pancreatic acinar cell. Caffeine did not block the Ca2+ entry, but significantly inhibited carbamylcholine (CCh)-induced Ca2+ release. In contrast, 2-APB did not block CCh-induced Ca2+ release, but remarkably blocked SOC-mediated Ca2+ entry at lower concentrations. In permeabilized acinar cell, caffeine had an inhibitory effect on InsP3-induced Ca2+ release, but 2-APB at lower concentration, which effectively blocked Ca2+ entry, had no inhibitory action. At higher concentrations, 2-APB has multiple paradoxical effects including inhibition of InsP3-induced Ca2+ release and direct stimulation of Ca2+ release. Based on the results, we concluded that caffeine is useful as an inhibitor of InsP3R, and 2-APB at lower concentration is considered a blocker of Ca2+ entry through SOC channels in the pancreatic acinar cell.


Assuntos
Animais , Camundongos , Células Acinares , Compostos de Boro , Cafeína , Cálcio , Carbacol , Receptores de Inositol 1,4,5-Trifosfato , Membranas , Retículo
14.
Artigo em Chinês | WPRIM | ID: wpr-246605

RESUMO

<p><b>OBJECTIVE</b>To study the effects of two primers on the bond strengths between casting pure titanium and resin cements.</p><p><b>METHODS</b>Two sizes of specimen were fabricated by casting, which diameter were 4 mm and 5 mm respectively, and then were cut into 3 mm thick titanium discs. The titanium surfaces were polished with silicon carbide sand papers under running water and then treated by sandblasting. The two size of titanium discs were ultrasonic cleaned and treated with Alloy Primer, V-Primer or without primer, and then bonded in pairs with the resin-based cements Super-Bond C&B, Panavia F and Rely X Unicem. The specimens were then stored in distilled water (37 degrees C) for 24 h. Bond strengths were determined before and after 5 000 thermocycling. The titanium surface morphous and failure mode of the teat specimen were observed.</p><p><b>RESULTS</b>The shear bond strengths of titanium treated by Alloy Primer to Super-Bond C&B were (31.23 +/- 4.86), (34.08 +/- 3.36) MPa before and after 5 000 thermocycling, which higher than that of other combinations of primers and resin cements.</p><p><b>CONCLUSION</b>Bond strengths were influenced by primers, resin cements, and their combinations. The highest bond strengths were the combinations of Alloy Primer and Super-Bond C&B.</p>


Assuntos
Compostos de Boro , Colagem Dentária , Esmalte Dentário , Fluorescência , Metacrilatos , Metilmetacrilatos , Cimentos de Resina , Tionas , Titânio , Triazinas
15.
Artigo em Inglês | IMSEAR | ID: sea-139709

RESUMO

Aims: To evaluate the effects of two different surface treatments and bonding agents on tensile bond strength between a Co-Cr and a Ni-Cr cast alloy and two resin-luting cements. Materials and Methods: Two hundred and forty alloy samples were cast and subjected to surface treatments such as sandblasting, chemical etching, and sandblasting plus chemical etching. Panavia F and CandB cement were used as cementing mediums. The etching qualities were examined by a stereooptic microscope. Failure surfaces were examined throughout scanning electron microscopy. The data were evaluated using statistical methods, namely analysis of variance and multiple comparison test (Tukey HSD). Results: Significant differences were found in the bonding provided by the various cements (P < 0.001) and also type of surface treatments (P < 0.001). For all groups, sandblasted surfaces showed the highest bond strength values. There was no significant difference between the Cr-Co and the Cr-Ni alloys (P > 0.05). Conclusions: Panavia F showed higher tensile strength and the sandblasted samples possessed higher tensile strength.


Assuntos
Condicionamento Ácido do Dente/métodos , Adesividade , Óxido de Alumínio/química , Compostos de Boro/química , Ligas de Cromo/química , Cobalto/química , Resinas Compostas/química , Ligas Dentárias/química , Colagem Dentária , Corrosão Dentária/métodos , Polimento Dentário/instrumentação , Polimento Dentário/métodos , Humanos , Teste de Materiais , Metacrilatos/química , Metilmetacrilatos/química , Microscopia Eletrônica de Varredura , Níquel/química , Cimentos de Resina/química , Estresse Mecânico , Propriedades de Superfície , Temperatura , Resistência à Tração , Fatores de Tempo , Água/química
16.
Artigo em Coreano | WPRIM | ID: wpr-125390

RESUMO

We evaluated in vitro microleakage of Mineral Trioxide Aggregate (MTA) powder with 4-methacryloxyethyl trimellitate anhydride (4-META) / methyl methacrylate (MMA) & tri-n-butylborane (TBB) resin as a retrograde filling material by using methylene blue dye method. Fifty-two single rooted, extracted teeth were instrumented and obturated with gutta percha and AH plus sealer. The apical 3mm of each root was resected and 3mm deep ultrasonic root end preparation was done. External surface of roots was coated with nail varnish. Prepared teeth were randomly divided into five groups; Negative control: completely covered with nail varnish; Positive control: coated with nail varnish except for apical foramen; Group 1 (retrofilled with Portland cement); Group 2 (retrofilled with MTA); Group 3 (retrofilled with MTA powder mixed with 4-META/MMA & TBB resin). Immediately after completion of root-end filling, all specimens were submerged in methylene blue dye for 72 hours in 37degrees C incubator. The roots were longitudinally sectioned and measured for extent of dye penetration by three different examiners under microscope (x10). The results were statistically analyzed using one way ANOVA and Turkey's HSD test. No leakage was evident in negative control and complete leakage in positive control group. Group 3 showed significantly less leakage than group 1 and 2 (p 0.01). It was concluded that MTA powder with 4-META/MMA & TBB resin was excellent in reducing initial apical microleakage.


Assuntos
Compostos de Alumínio , Compostos de Boro , Compostos de Cálcio , Combinação de Medicamentos , Resinas Epóxi , Glutamatos , Guanina , Guta-Percha , Incubadoras , Azul de Metileno , Unhas , Óxidos , Pintura , Materiais Restauradores do Canal Radicular , Silicatos , Dente , Ultrassom , Pemetrexede
17.
Artigo em Coreano | WPRIM | ID: wpr-220743

RESUMO

BACKGROUND: We evaluated multiplex PCR for species identification and toxin typing to improve the sensitivity and turnaround time of toxigenic Clostridium difficile culture (TCDC). METHODS: We performed multiplex PCR using primers targeting the species-specific gene, tpi, and the toxin genes, tcdA and tcdB. From January to March 2008, 528 stool specimens were tested with direct toxin assay (DT) using C. difficile Tox A/B II (Techlab, Blacksburg, USA) and TCDC. For 288 specimens from early study period, toxin production by C. difficile isolates of TCDC was measured by enzyme immunoassay with culture supernatants using VIDAS C. difficile Toxin A&B (CDAB;bioMerieux, Marcy-l'Etoile, France) and multiplex PCR with isolated colonies. For 240 specimens from late period, only multiplex PCR was used to test toxin production by the isolates. RESULTS: During the early period, 29 C. difficile were isolated and their toxin-positive rates were 65.5% by PCR and 44.8% by CDAB (P<0.05). Among 528 stool specimens, the results of DT+/TCDC+, DT+/ TCDC-, and DT-/TCDC+ were 32 (6.1%), 33 (6.3%), and 10 (1.9%), respectively, when tested with PCR. 13.3% of total 75 positive specimens was detected only by TCDC. Of the 42 toxigenic C. difficile isolates, all were positive for tpi, 30 (71.4%) were tcdA+/tcdB+, and 12 (28.6%) were tcdA-/tcdB+. CONCLUSION: TCDC using multiplex PCR for species identification and toxin typing is sensitive and rapid to be used as a routine diagnostic test.


Assuntos
Compostos de Boro , Clostridium , Clostridioides difficile , Testes Diagnósticos de Rotina , Técnicas Imunoenzimáticas , Reação em Cadeia da Polimerase Multiplex , Reação em Cadeia da Polimerase
18.
Acta Physiologica Sinica ; (6): 65-73, 2008.
Artigo em Chinês | WPRIM | ID: wpr-316759

RESUMO

The aim of the present study was to investigate the effects of inositol 1,4,5-trisphosphate (IP(3))-generating agonist UTP on spontaneous transient outward currents (STOCs), and explore the role of intracellular Ca(2+) release in the current response mediated by IP(3) in porcine coronary artery smooth muscle cells (CASMCs). The coronary artery was excised from the fresh porcine heart and cut into small segments (2 mm × 5 mm) and then transferred to enzymatic dissociation solution for incubation. Single CASMCs were obtained by two-step enzyme digestion at 37 °C. STOCs were recorded and characterized using the perforated whole-cell patch-clamp configuration in freshly isolated porcine CASMCs. The currents were amplified and filtered by patch-clamp amplifier (Axopatch 200B), and then the digitized data were recorded by pClamp 9.0 software and further analyzed by MiniAnalysis 6.0 program. The results were as follows: (1) UTP led to conspicuous increases in STOC amplitude by (57.54±5.34)% and in frequency by (77.46±8.42)% (P<0.01, n=38). (2) The specific blocker of phospholipase C (PLC) - U73122 (5 μmol/L) remarkably reduced STOC amplitude by (31.04±7.46)% and frequency by (41.65±16.59)%, respectively (P<0.05, n=10). In the presence of U73122, UTP failed to reactivate STOCs (n=7). (3) Verapamil (20 μmol/L) and CdCl2 (200 μmol/L), two blockers of L-type voltage-dependent Ca(2+) channels, had little effects on STOCs initiated by UTP (n=8). (4) 1 μmol/L bisindolylmaleimide I (BisI), a potent blocker of protein kinase C (PKC), significantly increased STOC amplitude by (65.44±24.66)% and frequency by (61.35±21.47)% (P<0.01, n=12); UTP (40 μmol/L), applied in the presence of 1 μmol/L BisI, could further increase STOC activity (P<0.05, P<0.01, n=12). Subsequent application of ryanodine (50 μmol/L) abolished STOC activity. (5) In the presence of UTP (40 μmol/L), inhibition of IP(3) receptors (IP(3)Rs) by 2-aminoethoxydiphenyl borate (2-APB, 40 μmol/L) reduced STOC amplitude by (24.08±3.97)% (P<0.05, n=8), but had little effect on STOC frequency (n=8). While application of 2-APB (80 μmol/L) significantly reduced STOC amplitude by (31.43±6.34)% and frequency by (40.59±19.01)%, respectively (P<0.05, P<0.01, n=6). Subsequent application of ryanodine (50 μmol/L) completely blocked STOC activity. Pretreatment of cells with 2-APB (40 μmol/L) or ryanodine (50 μmol/L), UTP (40 μmol/L) failed to reactivate STOCs. The results suggest that UTP activates STOCs mainly via PLC and IP(3)-dependent mechanisms. Complex Ca(2+)-mobilization pathways are involved in UTP-mediated STOC activation in porcine CASMCs.


Assuntos
Animais , Compostos de Boro , Farmacologia , Cálcio , Metabolismo , Vasos Coronários , Biologia Celular , Inositol 1,4,5-Trifosfato , Metabolismo , Miócitos de Músculo Liso , Metabolismo , Proteína Quinase C , Metabolismo , Rianodina , Farmacologia , Transdução de Sinais , Suínos , Fosfolipases Tipo C , Metabolismo , Uridina Trifosfato , Metabolismo
19.
Artigo em Coreano | WPRIM | ID: wpr-217983

RESUMO

BACKGROUND: Toxin immunoassay is widely used for rapid diagnosis of Clostridium difficile-associated diarrhea. The aim of this study was to evaluate the performance of Tox A/B Quik Chek test (TECHLAB, Blacksburg, VA, USA) compared to toxigenic culture. METHODS: From September 2006 to August 2007, 959 stools were examined by Tox A/B Quik Chek test and toxigenic culture (C. difficile culture plus tcdB PCR using colonies obtained from culture). RESULTS: Compared to the results of toxigenic culture, the sensitivity and specificity of Tox A/B Quik Chek test were 47.5% and 97.5%, respectively. CONCLUSION: The sensitivity of Tox A/B Quik Chek test was not high, but the specificity was high. Although Tox A/B Quik Chek test alone is not sufficient to diagnose Clostridium difficile-associated diarrhea, it may aid rapid diagnosis, early treatment and prevention of nosocomial spread of the infection, if supplemented by C. difficile culture or tissue culture cytotoxin assay.


Assuntos
Proteínas de Bactérias , Toxinas Bacterianas , Compostos de Boro , Clostridium , Clostridioides difficile , Diarreia , Diagnóstico Precoce , Enterotoxinas , Imunoensaio , Técnicas Imunoenzimáticas , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
20.
Artigo em Chinês | WPRIM | ID: wpr-296698

RESUMO

<p><b>OBJECTIVE</b>To evaluate the effect of Zinc oxide-eugenol cement and Gluma desensitizer on the sheer bond strength of three kinds of dentin bonding agents. The three dentin bonding agents were Zinc phosphate cement, Glass ionomer cement and Super-Bond C&B. To find the theory depending for the using of different protective methods and the selecting of different kinds of dentin bonding agents in prepared abutment teeth.</p><p><b>METHODS</b>The buccal surfaces of ninety freshly extracted human premolars were flattened to expose an adequate area of lower dentin. Followed by wet-grinding on a series of silicon carbide paper from number 320, 400, 600 grit to produce the dentin bonding surface. The teeth roots were embedded in self-curing resin with the crown out of the resin. The embedded ninety teeth were divided randomly into three groups. The group A was control and the dentin surfaces were not treated. The group B was covered with a paste of Zinc oxide-eugenol cement. The group C was covered with Gluma desensitizer. Calculating the sheer strength between three bonding agents and dentin after the two treatments of dentin surface. The results were statistically assessed with SPSS software. Dentin surfaces were observed with scanning electron microscope (SEM).</p><p><b>RESULTS</b>The sheer bond strengths of Zinc phosphate cement had significant decrease (P<0.05), especially the C1 group. The sheer bond strengths of Glass ionomer cement and Super-Bond C&B had no significant difference.</p><p><b>CONCLUSION</b>Zinc oxide-eugenol cement and Gluma desensitizer could reduce the sheer bond strength of Zinc phosphate cement with dentin surface. Zinc oxide-eugenol cement and the Gluma desensitizer could not effect Glass ionomer cement and the Super-Bond C&B with dentin.</p>


Assuntos
Humanos , Compostos de Boro , Coroas , Colagem Dentária , Dentina , Adesivos Dentinários , Glutaral , Metacrilatos , Metilmetacrilatos , Cimentos de Resina , Cimento de Óxido de Zinco e Eugenol
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