RESUMO
To evaluate the ethanol wet-bonding protocol with a universal adhesive in etch-andrinse and self-etch modes on microleakage and microtensile bond strength (µTBS) of resin composite to different dentin depth. Molars were distributed into groups according to protocol and dentin depth: universal adhesive (C - control), ethanol + universal adhesive (E), and phosphoric acid etch + ethanol + universal adhesive (PA+E). All protocols were applied to dentin at superficial, middle and deep depths. The specimens (n = 10) were submitted to microleakage and µTBS tests. Half of specimens were submitted to thermocycling (10,000 cycles; 5∘C/55∘C). Data were submitted to Spearman correlation (µTBS x microleakage) and three-way ANOVA (protocol, aging and depth), followed by Bonferroni post hoc test (α=0.05). PA+E group showed highest µTBS and lowest microleakage mean values in 24h. All groups presented similar µTBS mean values after thermocycling. The deep dentin showed less stable µTBS results. PA+E group presented highest microleakage mean values after thermocycling. Spearman's correlation showed a strong correlation between microleakage and µTBS. The PA+E group improved immediate adhesion and E group promoted a more stable µTBS in the long-term adhesion of universal adhesive. The aging for all protocols jeopardized the stability of the hybrid layer. The ethanol wet bonding technique associated with universal adhesive has enhanced the immediate result of the resin composite adhesion.
Assuntos
Colagem Dentária , Cimentos Dentários , Cimentos Dentários/farmacologia , Adesivos Dentinários/química , Colagem Dentária/métodos , Cimentos de Resina/química , Resistência à Tração , Dentina , Resinas Compostas/química , Teste de MateriaisRESUMO
INTRODUCTION: Ketamine (KET) is an anesthetic agent widely used in human and veterinary medicine. According to studies, KET is associated to direct neutorotoxic damages due to its capacity to induce oxidative stress. Because of the free radical generation in the organism and its relation with diseases' development, there is a growing interest to study antioxidant molecules, such as gallic acid (GA), a natural phenolic compound. AIM: Evaluate the GA antioxidant potential for the prevention of oxidative damage in the brain and liver tissue of rats exposed to acute KET administration. MATERIAL AND METHODS: 32 Wistar male rats received GA (by gavage, 13.5â¯mg/kg) for three consecutive days, 24â¯h after the last GA dose, animals were anesthetized with KET (50â¯mg/kg, i.m.). All animals were euthanized by decapitation 60â¯min after KET administration. The liver, brain cortex and hippocampus were removed and homogenized for biochemical analysis. RESULTS: In brain cortex, KET increased reactive species (RS) generation, protein carbonyls (PC) levels and reduced non-protein thiols (NPSH) levels, while GA pre-treatment reduced PC and increased NPSH levels. KET increased PC and decreased NPSH levels in the hippocampus, and GA reduced PC and NPSH levels. In the liver, no difference was observed in the RS generation, while KET induced and increase of PC levels and decreased NPSH levels, while GA pre-treatment prevented it. CONCLUSION: GA administration can prevent oxidative damage caused by acute KET administration and minimize its noxious effects. Further studies are needed to evidence GA antioxidant properties regarding KET chronic use.
Assuntos
Anestésicos Dissociativos/toxicidade , Córtex Cerebral/efeitos dos fármacos , Ácido Gálico/farmacologia , Hipocampo/efeitos dos fármacos , Ketamina/toxicidade , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Hipocampo/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Carbonilação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Compostos de Sulfidrila/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismoRESUMO
A hiperplasia prostática benigna é uma alteração comumente encontrada em cães de meia-idade e idosos não castrados, que se caracteriza pela hipertrofia e principalmente pela hiperplasia das células epiteliais e estromais da próstata. Os sinais clínicos, quando observados, estão relacionados com a compressão da uretra e do cólon, ocasionados pelo aumento excessivo dessa glândula. Embora a patogenia da hiperplasia prostática benigna não seja totalmente compreendida, a dihidrotestosterona (DHT) é considerada o principal hormônio envolvido na estimulação do aumento da próstata canina. O diagnóstico é feito principalmente por meio da anamnese/exame físico e do exame ultrassonográfico por meio dos quais são verificadas sintomatologia e alteração na dimensão da glândula. O tratamento de eleição é a orquiectomia bilateral, pois se trata de uma patologia andrógeno-dependente. O diagnóstico precoce dessa afecção permite a prevenção de outros distúrbios prostáticos, visto que a hiperplasia prostática predispõe ao surgimento de outras prostatopatias. Este artigo revisa os procedimentos diagnósticos, os avanços e as descobertas recentes sobre a hiperplasia prostática benigna na espécie canina.(AU)
Benign prostatic hyperplasia is a disorder commonly found in middle-aged and un-neutered dogs, characterized by hypertrophy and mainly hyperplasia of prostatic epithelial and stromal cells. The clinical signs, when observed, are related to the compression of the urethra and the colon, caused by the excessive increase of this gland. Although the pathogenesis of benign prostatic hyperplasia is not fully understood, dihydrotestosterone (DHT) is considered the main hormone involved in the stimulation of canine prostate enlargement. The diagnosis is made mainly through anamnesis/physical examination and ultrasonographic examination, in which symptomatology and alteration in the gland dimension are observed. The treatment of choice is bilateral orchiectomy, since it is an androgen-dependent pathology. The early diagnosis of this condition allows the prevention of other prostatic disorders, since prostatic hyperplasia predisposes the appearance of other prostate pathologies. This manuscript reviews the diagnosis procedures, the advances and the recent discoveries about canine benign prostatic hyperplasia.(AU)
Assuntos
Animais , Cães , Cães/anormalidades , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/veterinária , Hiperplasia Prostática/patologia , Di-HidrotestosteronaRESUMO
A hiperplasia prostática benigna é uma alteração comumente encontrada em cães de meia-idade e idosos não castrados, que se caracteriza pela hipertrofia e principalmente pela hiperplasia das células epiteliais e estromais da próstata. Os sinais clínicos, quando observados, estão relacionados com a compressão da uretra e do cólon, ocasionados pelo aumento excessivo dessa glândula. Embora a patogenia da hiperplasia prostática benigna não seja totalmente compreendida, a dihidrotestosterona (DHT) é considerada o principal hormônio envolvido na estimulação do aumento da próstata canina. O diagnóstico é feito principalmente por meio da anamnese/exame físico e do exame ultrassonográfico por meio dos quais são verificadas sintomatologia e alteração na dimensão da glândula. O tratamento de eleição é a orquiectomia bilateral, pois se trata de uma patologia andrógeno-dependente. O diagnóstico precoce dessa afecção permite a prevenção de outros distúrbios prostáticos, visto que a hiperplasia prostática predispõe ao surgimento de outras prostatopatias. Este artigo revisa os procedimentos diagnósticos, os avanços e as descobertas recentes sobre a hiperplasia prostática benigna na espécie canina.
Benign prostatic hyperplasia is a disorder commonly found in middle-aged and un-neutered dogs, characterized by hypertrophy and mainly hyperplasia of prostatic epithelial and stromal cells. The clinical signs, when observed, are related to the compression of the urethra and the colon, caused by the excessive increase of this gland. Although the pathogenesis of benign prostatic hyperplasia is not fully understood, dihydrotestosterone (DHT) is considered the main hormone involved in the stimulation of canine prostate enlargement. The diagnosis is made mainly through anamnesis/physical examination and ultrasonographic examination, in which symptomatology and alteration in the gland dimension are observed. The treatment of choice is bilateral orchiectomy, since it is an androgen-dependent pathology. The early diagnosis of this condition allows the prevention of other prostatic disorders, since prostatic hyperplasia predisposes the appearance of other prostate pathologies. This manuscript reviews the diagnosis procedures, the advances and the recent discoveries about canine benign prostatic hyperplasia.
Assuntos
Animais , Cães , Cães/anormalidades , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/patologia , Hiperplasia Prostática/veterinária , Di-HidrotestosteronaRESUMO
The main objective of this study was to determine if administration of meloxicam, a cyclooxygenase (COX) two inhibitor, to heifers in which embryo transfer (ET) is more difficult and requires a greater manipulation of the tract, would be beneficial. Nulliparous recipient heifers were divided in two groups: CON (n = 102), in which animals received 10 ml of saline IM (the same volume of meloxicam) and MEL (n = 105) animals that were treated with meloxicam. According to the degree in passing the catheter, recipients from both groups were classified as Grade I, easy (< 60 s), and Grade II (more than 80 s), difficult. Immediately after embryo transfer, MEL recipients received an injection of 200 mg of meloxicam (10 ml).There was no difference in the pregnancy rates on Day 35 considering animals which presented Grade I cervix independently whether the treatment was performed or not (p = 0.22). There was a statistical difference in the pregnancy rates (p < 0.01) between both groups (49.0% and 66.7% for CON and MEL, respectively) when cervical grade was not considered, on Day 35. Considering the animals that presented Grade II cervix, the pregnancy rate was higher for MEL (21.15% and 78.84%, respectively) in both examinations (p < 0.01).The authors concluded that meloxicam had a positive influence on general pregnancy rate of treated heifers in comparison to non-treated heifers. It was also observed that pregnancy rate was not influenced by meloxicam administration in Grade I heifers. Treatment increased the pregnancy rate of Grade II heifers.
Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Bovinos/fisiologia , Transferência Embrionária/veterinária , Fertilização in vitro/veterinária , Tiazinas/farmacologia , Tiazóis/farmacologia , Animais , Técnicas de Cultura Embrionária/veterinária , Feminino , Meloxicam , GravidezRESUMO
This study evaluated the effect of dentin pretreatment with 2% chlorhexidine (CHX) or 24% ethylenediamine tetra-acetic acid gel (EDTA) on the dentin microtensile bond strength (µTBS) of resin cements. Composite blocks were luted to superficial noncarious human dentin (n=10) using two resin cements (RelyX ARC [ARC] and RelyX U100 [U100]) and three dentin pretreatments (without pretreatment-control, CHX, and EDTA). CHX was applied for 60 seconds on the acid-etched dentin in the ARC/CHX group, and for the same time on smear layer-covered dentin in the U100/CHX group. EDTA was applied for 45 seconds on smear-covered dentin in the U100/EDTA group, and it replaced phosphoric acid conditioning in the ARC/EDTA group for 60 seconds. After storage in water for 24 hours, specimens were prepared for microtensile bond strength testing. The results were submitted to two-way analysis of variance (ANOVA) followed by Tukey test. ARC produced significantly higher µTBS (p<0.05) compared to the U100, except when EDTA was used. For ARC, no pretreatment and CHX produced higher µTBS than EDTA. For U100, EDTA produced higher µTBS; no statistical difference occurred between CHX pretreatment and when no pretreatment was performed. While CHX did not affect immediate dentin bond strength of both cements, EDTA improved bond strength of U100, but it reduced dentin bond strength of ARC.
Assuntos
Clorexidina/química , Colagem Dentária , Dentina/ultraestrutura , Ácido Edético/química , Inibidores de Metaloproteinases de Matriz , Cimentos de Resina/química , Condicionamento Ácido do Dente/métodos , Bis-Fenol A-Glicidil Metacrilato/química , Resinas Compostas/química , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Metacrilatos/química , Microscopia Eletrônica de Varredura , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Camada de Esfregaço , Estresse Mecânico , Propriedades de Superfície , Resistência à Tração , Fatores de Tempo , Água/químicaRESUMO
The present study describes the ultrastructural characteristics of cat oocytes before maturation and after 12- and 24-h in vitro maturation (IVM). Oocytes were recovered from pre-pubertal and adult queen ovaries after ovariohysterectomy and a proportion were stored in glutaraldehyde at 4 degrees C until examination by transmission electronic microscopy (TEM). Those selected for maturation were cultured before TEM in DMEM for 12 and 24 h at 38 degrees C in a humidified environment of 5% O(2), 5% CO(2) and 90% N(2). Specimens were divided into six groups: non-matured oocytes from pre-pubertal queens (PP0), non-matured oocytes from adult queens (A0), 12-h in vitro matured oocytes from pre-pubertal queens (PP12), 12-h in vitro matured oocytes from adult queens (A12), 24-h in vitro matured oocytes from pre-pubertal queens (PP24) and 24-h in vitro matured oocytes from adult queens (A24). Across the treatment groups, it was possible to observe differences in the thickness of the perivitelline space, the penetration of cumulus cell projections forming a junctional complex, distribution and density of small vesicles, lipid droplets, microvilli, mitochondria and cortical granules and variable degrees of development of Golgi complexes. These findings demonstrated that ultrastructural analysis of oocytes matured in vitro is a valuable tool to evaluate oocyte cytoplasmic maturation and that this IVM protocol was efficient in inducing gradual morphological changes necessary for cytoplasmic maturation of pre-pubertal and adult cat oocytes.
Assuntos
Gatos , Oócitos/ultraestrutura , Ovário/fisiologia , Animais , Células Cultivadas , Feminino , Células da Granulosa/ultraestrutura , Maturidade SexualRESUMO
A comparative study on the potential of some biological agents to perform the hydrolysis of stevioside was carried out, aiming at establishing an alternative methodology to achieve the aglycon steviol or its rearranged derivative isosteviol, in high yields to be used in the preparation of novel bioactive compounds. Hydrolysis reactions were performed by using filamentous fungi (Aspergillus niger, Rhizopus stolonifer and Rhizopus arrhizus), a yeast (Saccharomyces cerevisiae) and enzymes (pancreatin and lipases PL250 and VFL 8000). Pancreatin showed the best hydrolytic activity, furnishing isosteviol at 93.9% of yield, at pH 4.0, using toluene as a co-solvent. Steviol was produced using both pancreatin at pH 7.0 (20.2% yield) and A. niger atpH 7 (20.8% yield).
Um estudo comparativo do potencial de alguns agentes biológicos capazes de hidrolisar o esteviosídeo foi realizado,objetivando-se estabelecer uma metodologia alternativa para a obtenção da aglicona esteviol ou seu produto de rearranjo, isoesteviol, em rendimentos elevados que permitam o uso destas agliconas para o preparo de novos compostos bioativos. As reações de hidrólise foram realizadas usando fungosfilamentosos (Aspergillus niger, Rhizopus stolonifer e Rhizopus arrhizus), uma levedura (Saccharomyces cerevisiae) e enzimas(pancreatina, lipase PL250 e lipase VFL 8000). A pancreatina mostrou a melhor atividade hidrolítica dentre os sistemastestados, fornecendo isoesteviol com rendimento de 93,9% em pH 4,0, usando tolueno como co-solvente. Esteviol foi produzido tanto usando pancreatina em pH 7,0 (20,2% derendimento) quanto usando A. niger em pH 7,0 (20,8% de rendimento).
Assuntos
Reações Biológicas , Fungos/enzimologia , Fungos/isolamento & purificação , Lipase/análise , Pancreatina/análise , Stevia/enzimologia , Cromatografia Líquida de Alta Pressão , Hidrólise , Métodos , MétodosRESUMO
A comparative study on the potential of some biological agents to perform the hydrolysis of stevioside was carried out, aiming at establishing an alternative methodology to achieve the aglycon steviol or its rearranged derivative isosteviol, in high yields to be used in the preparation of novel bioactive compounds. Hydrolysis reactions were performed by using filamentous fungi (Aspergillus niger, Rhizopus stolonifer and Rhizopus arrhizus), a yeast (Saccharomyces cerevisiae) and enzymes (pancreatin and lipases PL250 and VFL 8000). Pancreatin showed the best hydrolytic activity, furnishing isosteviol at 93.9% of yield, at pH 4.0, using toluene as a co-solvent. Steviol was produced using both pancreatin at pH 7.0 (20.2% yield) and A. niger at pH 7 (20.8% yield).
RESUMO
A comparative study on the potential of some biological agents to perform the hydrolysis of stevioside was carried out, aiming at establishing an alternative methodology to achieve the aglycon steviol or its rearranged derivative isosteviol, in high yields to be used in the preparation of novel bioactive compounds. Hydrolysis reactions were performed by using filamentous fungi (Aspergillus niger, Rhizopus stolonifer and Rhizopus arrhizus), a yeast (Saccharomyces cerevisiae)andenzymes (pancreatin and lipases PL250 and VFL 8000). Pancreatin showed the best hydrolytic activity, furnishing isosteviol at 93.9% of yield, at pH 4.0, using toluene as a co-solvent. Steviol was produced using both pancreatin at pH 7.0 (20.2% yield) and A. niger at pH 7 (20.8% yield).
Um estudo comparativo do potencial de alguns agentes biológicos capazes de hidrolisar o esteviosídeo foi realizado, objetivando-se estabelecer uma metodologia alternativa para a obtenção da aglicona esteviol ou seu produto de rearranjo, isoesteviol, em rendimentos elevados que permitam o uso destas agliconas para o preparo de novos compostos bioativos. As reações de hidrólise foram realizadas usando fungos filamentosos (Aspergillus niger, Rhizopus stolonifer e Rhizopus arrhizus), uma levedura (Saccharomyces cerevisiae)e enzimas(pancreatina, lipase PL250 e lipase VFL 8000). A pancreatina mostrou a melhor atividade hidrolítica dentre os sistemas testados, fornecendo isoesteviol com rendimento de 93,9% em pH 4,0, usando tolueno como co-solvente. Esteviol foi produzido tanto usando pancreatina em pH 7,0 (20,2% de rendimento) quanto usando A. niger em pH 7,0 (20,8% de rendimento).
RESUMO
T-cell acute lymphoblastic leukemia (T-ALL) is a biologically heterogeneous disease with respect to phenotype, gene expression profile and activation of particular intracellular signaling pathways. Despite very significant improvements, current therapeutic regimens still fail to cure a portion of the patients and frequently implicate the use of aggressive protocols with long-term side effects. In this review, we focused on how deregulation of critical signaling pathways, in particular Notch, PI3K/Akt, MAPK, Jak/STAT and TGF-beta, may contribute to T-ALL. Identifying the alterations that affect intracellular pathways that regulate cell cycle and apoptosis is essential to understanding the biology of this malignancy, to define more effective markers for the correct stratification of patients into appropriate therapeutic regimens and to identify novel targets for the development of specific, less detrimental therapies for T-ALL.
Assuntos
Diferenciação Celular , Leucemia-Linfoma de Células T do Adulto , Fosfotransferases/fisiologia , Transdução de Sinais/fisiologia , Linfócitos T/citologia , Humanos , Janus Quinases/fisiologia , Leucemia-Linfoma de Células T do Adulto/etiologia , Leucemia-Linfoma de Células T do Adulto/fisiopatologia , Leucemia-Linfoma de Células T do Adulto/terapia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/fisiologia , Receptores Notch/fisiologia , Fator de Crescimento Transformador beta/fisiologiaRESUMO
T-cell acute lymphoblastic leukemia (T-ALL) is a biologically heterogeneous disease with respect to phenotype, gene expression profile and activation of particular intracellular signaling pathways. Despite very significant improvements, current therapeutic regimens still fail to cure a portion of the patients and frequently implicate the use of aggressive protocols with long-term side effects. In this review, we focused on how deregulation of critical signaling pathways, in particular Notch, PI3K/Akt, MAPK, Jak/STAT and TGF-ß, may contribute to T-ALL. Identifying the alterations that affect intracellular pathways that regulate cell cycle and apoptosis is essential to understanding the biology of this malignancy, to define more effective markers for the correct stratification of patients into appropriate therapeutic regimens and to identify novel targets for the development of specific, less detrimental therapies for T-ALL.
Assuntos
Humanos , Diferenciação Celular , Leucemia-Linfoma de Células T do Adulto , Fosfotransferases/fisiologia , Transdução de Sinais/fisiologia , Linfócitos T/citologia , /fisiologia , Janus Quinases/fisiologia , Leucemia-Linfoma de Células T do Adulto/etiologia , Leucemia-Linfoma de Células T do Adulto/fisiopatologia , Leucemia-Linfoma de Células T do Adulto/terapia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Fosforilação , Proteínas Proto-Oncogênicas c-akt/fisiologia , Receptores Notch/fisiologia , Fator de Crescimento Transformador beta/fisiologiaRESUMO
AIM: To test the hypothesis that the composition of endodontic sealer cements and the time elapsed between root filling and fibreglass post fixation interferes with adhesion to root canal dentine. METHODOLOGY: Sixty bovine incisor roots were divided into five groups (n = 12): CI, unfilled; SI, filled with a calcium hydroxide-based cement-Sealer 26, and immediate post fixation; S7, Sealer 26 and post fixation after 7 days; EI, filled with a zinc oxide and eugenol-based cement-Endofill and immediate fixation; and E7 Endofill and post fixation after 7 days. The posts were cemented with adhesive system and dual resin cement. Ten roots were cross-sectioned to obtain two 1-mm-thick discs for each cervical (TC), middle (TM) and apical (TA) third of the prepared root portion. The posts were submitted to a micropush-out test. The other two teeth were evaluated using scanning electron microscopy to analyse the bond interface. Data were analysed using anova, Tukey and Dunnett tests (P < 0.05). RESULTS: Group EI was associated with a significant reduction in bond strength values irrespective of the root region; TC = 3.50 MPa (P = 0.0001); TM = 2.22 MPa (P = 0.0043) and TA = 1.45 MPa (P = 0.003). Region of canal had an influence on the values for the cement used in group E7, in which only the TA presented differences from the CI. CONCLUSIONS: Endofill interfered negatively with the bond to root dentine along its full length and in the TA when post fixation was delayed for 7 days. Bond strength decreased from crown to apex in all groups.
Assuntos
Cimentos Dentários/química , Adaptação Marginal Dentária , Dentina/efeitos dos fármacos , Técnica para Retentor Intrarradicular , Materiais Restauradores do Canal Radicular/química , Obturação do Canal Radicular/métodos , Animais , Bismuto/química , Bismuto/uso terapêutico , Hidróxido de Cálcio/química , Hidróxido de Cálcio/uso terapêutico , Bovinos , Colagem Dentária/métodos , Retenção em Prótese Dentária/métodos , Análise do Estresse Dentário , Interações Medicamentosas , Vidro/química , Técnicas In Vitro , Incisivo , Cimentos de Resina/química , Cimentos de Resina/uso terapêutico , Materiais Restauradores do Canal Radicular/uso terapêutico , Estresse Mecânico , Propriedades de Superfície , Fatores de Tempo , Raiz Dentária/efeitos dos fármacos , Cimento de Óxido de Zinco e Eugenol/química , Cimento de Óxido de Zinco e Eugenol/uso terapêuticoRESUMO
PURPOSE: To determine the correlation between the tubule density (TD) and the area occupied by solid dentin (ASD) with the bond strength of one conventional and one self-etching adhesive system to dentin. MATERIALS AND METHODS: The crown of extracted human third molars was transversally sectioned with a diamond saw to expose either superficial, middle, or deep dentin. The three groups of dentin surfaces were randomly divided and bonded with either Clearfil Liner Bond 2V (LB) or Prime & Bond 2.1 (PB) adhesive systems according to manufacturer's directions. Resin composite buildup crowns (10.0 mm high) were incrementally constructed on the bonded surfaces and the teeth stored in water at 37 degrees C. After 24 h of storage, the teeth were vertically, serially sectioned in both x and y directions to obtain several bonded sticks of approximately 0.7 mm2 cross-sectional area. Each stick was tested in tension in a EMIC DL-500 tester at 0.5 mm/min until failure. After testing, the dentin side of the fractured specimen was gently abraded with a 1000-grit SiC paper, etched with 37% phosphoric acid for 15 s and allowed to air dry. SEM micrographs at 1000x and 4000x magnification were taken to permit calculation of the TD (number of tubules/mm2) and ASD (% of total area) at the site of fracture. Correlation between TD and ASD with the bond strength data was performed by linear regression. All statistical analysis was done with alpha = 0.05. RESULTS: Overall bond strength (MPa) for LB was 26.0 +/- 10.2, and 42.6 +/- 15.2 for PB. There was a significant direct relationship between bond strength and ASD for both materials (r2 = 0.20, p < 0.05 and r2 = 0.66, p < 0.01, respectively for LB and PB). PB bond strength dropped significantly as the TD increased (r2 = 0.63, p < 0.05), while LB was not sensitive to TD (r2 = 0.05, p > 0.05). Mean bond strength of PB was significantly higher than LB for both superficial and middle dentin (p < 0.05), while there was no significant difference for deep dentin (p > 0.05). CONCLUSION: Regional variations in TD and ASD may modify bond strength of both conventional and self-etching adhesive systems. Bonding sites with larger ASD seem to yield higher bond strengths regardless of the type of adhesive system used.
Assuntos
Colagem Dentária , Adesivos Dentinários/química , Dentina/ultraestrutura , Dióxido de Silício , Zircônio , Acetona/química , Condicionamento Ácido do Dente , Análise de Variância , Compostos Inorgânicos de Carbono , Resinas Compostas/química , Coroas , Humanos , Modelos Lineares , Metacrilatos/química , Microscopia Eletrônica de Varredura , Dente Serotino , Ácidos Fosfóricos/química , Ácidos Polimetacrílicos/química , Compostos de Silício , Estatística como Assunto , Estresse Mecânico , Propriedades de Superfície , Temperatura , Resistência à Tração , Fatores de Tempo , Água/químicaRESUMO
Conditions and artifacts such as aortic calcification, osteophytes, hip prostheses, and metallic objects can mislead the results of dual energy X-ray absorptiometry (DXA) scanning of the spine and hip. Gluteal silicon implants increasingly are being used for aesthetic purposes by women in Brazil, some of whom are at an age of high risk for the development of postmenopausal osteoporosis. We herein report a case of a woman whose hip bone mineral density by DXA clearly increased after the placement of bilateral gluteal implants of silicon. This case demonstrates the importance of inquiring about the presence of this artifact to avoid unnecessary evaluation of hip bone densitometry in these situations.
Assuntos
Densidade Óssea , Quadril/fisiologia , Próteses e Implantes , Elastômeros de Silicone , Absorciometria de Fóton , Adulto , Nádegas , Feminino , HumanosRESUMO
PURPOSE: To evaluate septal perfusion and contractility in patients with left bundle branch block (LBBB). METHODS: Twenty patients were submitted to myocardial scintigraphy with Tecnecium-99m isontrile after exercise and dipyridamole infusion. The septal contractility was observed during the radionuclide ventriculography. All patients were submitted to coronariography. RESULTS: Twenty patients were studied and 17 (85%) had a normal left anterior descending (LAD) artery. Nine (53%) patients had abnormalities in septal perfusion after the exercise and 2 (12%) after dipyridamole infusion. All patients had abnormalities in septal contractility during the radionuclide ventriculography. CONCLUSION: The myocardial scintigraphy after dipyridamole infusion showed better specificity in the diagnosis of a LAD lesion. The radionuclide ventriculography was an efficient method to evaluate the septal contraction abnormalities in patients with LBBB.