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1.
Oral Dis ; 25(1): 274-281, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29683234

RESUMO

OBJECTIVE: Masticatory muscle tendon-aponeurosis hyperplasia, which is associated with limited mouth opening, progresses very slowly from adolescence. The prevalence rates of this disease are higher among women than among men, suggesting oestrogen involvement. As parafunctional habits are frequently observed, mechanical stress is likely involved in the pathogenesis and advancement of this disease. To elucidate the pathological condition, we examined the effect of oestrogen on tenocyte function and the relationship between mechanical stress and crystallin beta A4 (Cryba4), using murine TT-D6 tenocytes. MATERIALS AND METHODS: Cell proliferation assays, RT-PCR, real-time RT-PCR, Western blot analysis and mechanical loading experiments were performed. RESULTS: The physiological dose of oestrogen increased the levels of scleraxis and tenomodulin in TT-D6 tenocytes. In contrast, forced expression of Cryba4 inhibited scleraxis expression in these cells. Surprisingly, oestrogen significantly promoted cell differentiation in the Cryba4-overexpressing TT-D6 tenocytes. Moreover, tensile force induced Cryba4 expression in these tendon cells. CONCLUSION: Oestrogen and Cryba4 may be associated with the progression of masticatory muscle tendon-aponeurosis hyperplasia.


Assuntos
Aponeurose/patologia , Estrogênios/fisiologia , Músculos da Mastigação/patologia , Tendões/patologia , Cadeia A de beta-Cristalina/genética , Animais , Células Cultivadas , Humanos , Hiperplasia , Camundongos , Estresse Mecânico
2.
Kyobu Geka ; 64(4): 291-5, 2011 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-21491723

RESUMO

Secondary spontaneous pneumothorax (SSP) such as lymphangioleiomyomatosis (LAM), bronchiolitis obliterans (BO) is intractable or repeated the recurrence of pneumothorax. The most effective chemical pleurodesis for intractable pneumothorax is talc poudrage and so on that is associated with a reduction in the rate of pneumothorax recurrence. However, severe and broad pleural adhesion due to the pleural interventional procedures sometimes cause serious bleeding when the patients undergo lung transplantation. We must be considered for new approaches to these intractable secondary pneumothoraces which replaced traditional conservative and surgical approaches. We had proposed new 2 approaches of total pleural covering (TPC) and awake surgical intervention (ASI) for intractable pneumothorax. We applied the TPC modified with coverage of air leak points with polyglycolic acid (PGA) sheet to 5 patients with intractable bilateral pneumothorax to reduce the risk of excessive bleeding by chemical pleurodesis in lung transplantation. The bilateral pneumothorax was well controlled, and no recurrence has been observed. TPC is reliable procedure for management intractable bilateral SSP. For 12 high-risk patients with other underling pulmonary diseases on general poor conditions, a surgical intervention was performed in awake condition. The air leaks were stopped in 11 cases except for 1 case. The recurrence of pneumothorax after surgery was 2 cases. ASI for intractable secondary pneumothorax can be applicable to selected patients with deteriorated general condition.


Assuntos
Pleura/cirurgia , Pneumotórax/cirurgia , Humanos , Ácido Poliglicólico
3.
J Biomed Mater Res A ; 83(1): 123-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17385233

RESUMO

Resin composites are widely used in dentistry, and are polymerized in situ using a blue-light activated, free-radical polymerization mechanism. Blue light (400-500nm) is used to activate camphoroquinone (CQ), which decomposes to form free radicals that are stabilized by dimethyl-p-toludine (DMPT). CQ and DMPT are applied near tooth pulpal tissues and are irradiated during restorative procedures, suggesting that pulpal cells are exposed to free radicals. Because glutathione is a major component of the cellular redox management system, we tested the hypothesis that blue light irradiation would shift cellular glutathione redox balance of cells exposed to CQ and DMPT. We also measured NFkappaB activation, a redox-sensitive transcription factor that regulates inflammatory responses and glutathione synthetic enzyme levels. THP1 human monocytes were exposed to sublethal levels of CQ (0.4 mM) or DMPT (1.0 mM), with or without blue light exposure (25 J/cm(2)) from a quartz-tungsten-halogen source. The ratio of reduced to oxidized glutathione was measured using as assay based on 5,5'-dithio-bis(2-nitrobenszoic acid). NFkappaB transactivation was measured by transfection of an NFkappaB-containing plasmid linked to a luciferase reporter. Our results showed that blue light, CQ, or DMPT alone had no significant effect on cellular glutathione redox balance, but that the combination of these agents induced a marked oxidative bias, and reduced total glutathione levels up to 50%. On the other hand, light, CQ, and DMPT alone or in combination suppressed NFkappaB transactivation by >70%. Our results suggest that CQ and DMPT pose risks to pulpal tissues with or without blue light irradiation, and that multiple, interacting mechanisms shape the response to these agents.


Assuntos
Radicais Livres/metabolismo , Luz , Monócitos/efeitos dos fármacos , Monócitos/efeitos da radiação , Terpenos/farmacologia , Toluidinas/farmacologia , Linhagem Celular , Glutationa/metabolismo , Humanos , Monócitos/enzimologia , Monócitos/metabolismo , NF-kappa B/genética , Oxirredução/efeitos dos fármacos , Oxirredução/efeitos da radiação , Succinato Desidrogenase/metabolismo , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/genética
4.
J Biomed Mater Res A ; 77(3): 470-7, 2006 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-16482554

RESUMO

Blue light from dental photopolymerization devices has significant biological effects on cells. These effects may alter normal cell function of tissues exposed during placement of oral restorations, but recent data suggest that some light-induced effects may also be therapeutically useful, for example in the treatment of epithelial cancers. Reactive oxygen species (ROS) appear to mediate blue light effects in cells, but the sources of ROS (intra- versus extracellular) and their respective roles in the cellular response to blue light are not known. In the current study, we tested the hypothesis that intra- and extracellular sources of blue light-generated ROS synergize to depress mitochondrial function. Normal human epidermal keratinocytes (NHEK) and oral squamous cell carcinoma (OSC2) cells were exposed to blue light (380-500 nm; 5-60 J/cm(2)) from a dental photopolymerization source (quartz-tungsten-halogen, 550 mW/cm(2)). Light was applied in cell-culture media or balanced salt solutions with or without cells present. Intracellular ROS levels were estimated using the dihydrofluorescein diacetate (DFDA) assay; extracellular ROS levels were estimated using the leucocrystal violet assay. Cell response was estimated using the MTT mitochondrial activity assay. Blue light increased intracellular ROS equally in both NHEK and OSC2. Blue light also increased ROS levels in cell-free MEM or salt solutions, and riboflavin supplements increased ROS formation. Extracellularly applied ROS rapidly (50-400 muM, <1 min) increased intracellular ROS levels, which were higher and longer-lived in NHEK than OSC2. The type of cell-culture medium significantly affected the ability of blue light to suppress cellular mitochondrial activity; the greatest suppression was observed in DMEM-containing or NHEK media. Collectively, the data support our hypothesis that intra- and extracellularly generated ROS synergize to affect cellular mitochondrial suppression of tumor cells in response to blue light. However, the identity of blue light targets that mediate these changes remain unclear. These data support additional investigations into the risks of coincident exposure of tissues to blue light during material polymerization of restorative materials, and possible therapeutic benefits.


Assuntos
Queratinócitos/metabolismo , Luz , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Humanos , Succinato Desidrogenase
5.
Biochim Biophys Acta ; 1034(2): 195-9, 1990 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-2112955

RESUMO

Cholera toxin causes the devastating diarrheal syndrome characteristic of cholera by catalyzing the ADP-ribosylation of Gs alpha, a GTP-binding regulatory protein, resulting in activation of adenylyl cyclase. ADP-ribosylation of Gs alpha is enhanced by 19 kDa guanine nucleotide-binding proteins known as ADP-ribosylation factors or ARFs. We investigated the effects of agents known to alter toxin-catalyzed activation of adenylyl cyclase on the stimulation of toxin- and toxin subunit-catalyzed ADP-ribosylation of Gs alpha and other substrates by an ADP-ribosylation factor purified from a soluble fraction of bovine brain (sARF II). In the presence of GTP, sARF II enhanced activity of both the toxin catalytic unit and a reduced and alkylated fragment ('A1'), as a result of an increase in substrate affinity with no significant effects on Vmax. Activation of toxin was independent of Gs alpha and was stimulated 4-fold by sodium dodecyl sulfate, but abolished by Triton X-100. sARF II therefore serves as a direct allosteric activator of the A1 protein and may thus amplify the pathological effects of cholera toxin.


Assuntos
Toxina da Cólera/metabolismo , Guanosina Trifosfato/farmacologia , Proteínas de Membrana/farmacologia , ADP Ribose Transferases/metabolismo , Fatores de Ribosilação do ADP , Adenosina Difosfato Ribose/metabolismo , Adenilil Ciclases/metabolismo , Animais , Química Encefálica , Bovinos , Ativação Enzimática/efeitos dos fármacos , Proteínas de Ligação ao GTP/metabolismo , Cinética , Peso Molecular , Octoxinol , Polietilenoglicóis/farmacologia , Dodecilsulfato de Sódio/farmacologia
6.
J Biomed Mater Res B Appl Biomater ; 73(2): 308-14, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15803495

RESUMO

The use of hydrophilic dental monomers in dentin bonding agents has vastly improved resin-dentin bond strengths, but incomplete polymerization of these monomers and their leaching into adjacent (pulpal) oral tissues has raised concerns about their biocompatibility. The sublethal effects of these resins are virtually unknown, but their electrophilic nature led to the hypothesis that they may alter cellular oxidative stress pathways. Glutathione balance between reduced (GSH) and oxidized (GSSG) is a major mechanism by which cells maintain redox balance and was therefore the focus of the current investigation. THP-1 human monocytic cells were exposed to hydroxyethyl methacrylate (HEMA), benzoyl peroxide (BPO), camphorquinone (CQ), or triethyelene glycol dimethacrylate (TEGDMA) for 24 h at sublethal doses, then GSH and GSSG levels were measured by means of Ellman's method adapted for cell culture. The results indicate that these dental resin compounds act at least partly via oxidative stress by increasing GSH levels at sublethal concentrations. However, the GSH-GSSG ratio was relatively unaffected. Only BPO altered the GSH-GSSG ratio at 24 h, again at sublethal levels (7.5-15 micromol/L). The results support the hypothesis that resin monomers act, at least in part, via oxidative stress, and that oxidative-stress pathways should be one focus of future investigations of monomer biocompatibility.


Assuntos
Adesivos Dentinários/farmacologia , Glutationa/metabolismo , Monócitos/fisiologia , Estresse Oxidativo/fisiologia , Butionina Sulfoximina/farmacologia , Linhagem Celular , Resinas Compostas/farmacologia , Dissulfeto de Glutationa/metabolismo , Glutationa Redutase/metabolismo , Humanos , Metacrilatos/farmacologia , Monócitos/efeitos dos fármacos , Oxirredução , Polietilenoglicóis/farmacologia , Ácidos Polimetacrílicos/farmacologia
7.
J Bone Miner Res ; 13(7): 1101-11, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9661074

RESUMO

We have used homologous recombination in embryonic stem cells to generate mice with a targeted disruption of the osteopontin (Opn, or Spp1, for secreted phosphoprotein 1) gene. Mice homozygous for this disruption fail to express osteopontin (OPN) as assessed at both the mRNA and protein level, although an N-terminal fragment of OPN is detectable at extremely low levels in the bones of -/- animals. The Opn -/- mice are fertile, their litter size is normal, and they develop normally. The bones and teeth of animals not expressing OPN are morphologically normal at the level of light and electron microscopy, and the skeletal structure of young animals is normal as assessed by radiography. Ultrastructurally, proteinaceous structures normally rich in OPN, such as cement lines, persist in the bones of the Opn-/- animals. Osteoclastogenesis was assessed in vitro in cocultures with a feeder layer of calvarial osteoblast cells from wild-type mice. Spleen cells from Opn-/- mice cells formed osteoclasts 3- to 13-fold more frequently than did control Opn+/+ cells, while the extent of osteoclast development from Opn -/- bone marrow cells was about 2- to 4-fold more than from the corresponding wild-type cells. Osteoclast development occurred when Opn-/- spleen cells were differentiated in the presence of Opn-/-osteoblasts, indicating that endogenous OPN is not required for this process. These results suggest that OPN is not essential for normal mouse development and osteogenesis, but can modulate osteoclast differentiation.


Assuntos
Desenvolvimento Ósseo/fisiologia , Osteoclastos/fisiologia , Sialoglicoproteínas/deficiência , Dente/crescimento & desenvolvimento , Animais , Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/ultraestrutura , Diferenciação Celular/genética , Técnicas de Cocultura , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos BALB C , Osteoblastos , Osteoclastos/ultraestrutura , Osteopontina , RNA Mensageiro/análise , Radiografia , Sialoglicoproteínas/análise , Sialoglicoproteínas/genética , Baço/citologia , Dente/ultraestrutura
8.
FEBS Lett ; 349(1): 13-6, 1994 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-8045289

RESUMO

In order to determine whether hydroxyapatite modulates the response of polymorphonuclear leukocyte (PMN) to oxidative stimuli, human PMNs were incubated with a non-activating concentration (1 or 10 micrograms/ml) of hydroxyapatite prior to stimulation with N-formyl-methionyl-leucyl-phenylalanine (FMLP; 0.1 or 1 microM), phorbol 12-myristate 13-acetate (PMA; 100 pg/ml), sodium fluoride (50 microM), zymosan (1 microgram/ml), or the calcium ionophore A23187 (0.1 microM). Chemiluminescence was measured with an automatic microcomputer-controlled luminescence analyzer at 37 degrees C. Hydroxyapatite alone did not stimulate chemiluminescence at concentrations below 10 micrograms/ml. Levels 300-400% higher than 'stimulus only' controls without preincubation with hydroxyapatite have been recorded. This synergism between hydroxyapatite and subsequent stimuli reveals a new activity of hydroxyapatite and suggests that particulate material may prepare PMNs for an exaggerated inflammatory response to other phlogistic mediators. This is the first report demonstrating PMNs primed with particulate material.


Assuntos
Durapatita/farmacologia , Medições Luminescentes , Neutrófilos/fisiologia , Calcimicina/farmacologia , Relação Dose-Resposta a Droga , Humanos , Inflamação/metabolismo , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/efeitos dos fármacos , Fluoreto de Sódio/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo , Zimosan/farmacologia
9.
Am J Clin Pathol ; 94(2): 217-21, 1990 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2371975

RESUMO

A 62-year-old woman was admitted for evaluation of muscular weakness, skin pigmentation, dry mouth, and interstitial pneumonia. During the course of her stay, adult respiratory distress syndrome, hemolytic anemia, renal failure, neurologic dysfunction, and thrombocytopenia appeared. A clinical diagnosis of thrombotic thrombocytopenic purpura (TTP) accompanied by polymyositis and Sjögren's syndrome was made. She died two weeks after the beginning of plasmapheresis, and an autopsy was performed. Immunohistochemistry disclosed deposits of IgM, fibrinogen, and C1q in glomeruli and arterioles and deposits of C3 in small arteries. von Willebrand's factor antigen, which promotes the adhesion of platelets to the subendothelium, was positive in onion-peeled arteries of the kidney and the spleen. These results suggest that immune complexes may have triggered a sequence of events from vascular endothelial injury to TTP.


Assuntos
Doenças Musculares/patologia , Púrpura Trombocitopênica Trombótica/patologia , Síndrome de Sjogren/patologia , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Doenças Musculares/complicações , Doenças Musculares/metabolismo , Púrpura Trombocitopênica Trombótica/complicações , Púrpura Trombocitopênica Trombótica/metabolismo , Síndrome de Sjogren/complicações , Síndrome de Sjogren/metabolismo
10.
J Dent Res ; 81(4): 265-9, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12097311

RESUMO

Few studies have investigated the ability of dental resins to induce cellular stress at sublethal concentrations. Cellular stress, especially in immune cells such as monocytes, may modulate the biological response to materials or the host's ability to respond to bacterially mediated inflammation. The current study examined the ability of sublethal concentrations of 2-hydroxylethylmethacrylate (HEMA) and triethyleneglycol dimethacrylate (TEGDMA) to induce heat shock protein 72 (HSP72) in human monocytes. HEMA and TEGDMA significantly suppressed heat-induced HSP72 expression, even at sublethal levels, but did not induce HSP72 by themselves. The results of the current study suggest that components released from dental resin could modulate the HSP stress response without altering cellular metabolic activity.


Assuntos
Adesivos Dentinários/toxicidade , Proteínas de Choque Térmico/biossíntese , Estresse Fisiológico/induzido quimicamente , Análise de Variância , Células Cultivadas , Eletroforese em Gel de Poliacrilamida , Proteínas de Choque Térmico HSP72 , Humanos , Immunoblotting , Metacrilatos/toxicidade , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Polietilenoglicóis/toxicidade , Ácidos Polimetacrílicos/toxicidade , Estatísticas não Paramétricas
11.
J Endod ; 25(3): 187-9, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10321184

RESUMO

This study compared the ability of bacterial detection from intracanal exudate by two different methods. One is a conventional method (i.e. the samples were transported into anaerobic chambers immediately after sampling and then moved to an outside laboratory for identification of bacteria). Another is a preculture method (i.e. the samples were inoculated into semisolid medium immediately after sampling, incubated for 24 h under anaerobic conditions, and then moved to the laboratory for bacterial identification). In 22 cases, the preculture method detected bacteria in 18 of 22 cases, whereas the conventional method detected bacteria in 6 of 22 cases. The preculture method showed significantly higher frequency of bacterial detection (p = 0.0003). Gram-positive cocci (alpha-Streptococcus, Enterococcus, etc.) were detected in many cases. These results suggested that the preculture method could be helpful in detecting root canal bacteria and enhance antibiotic treatment of endodontic disease.


Assuntos
Técnicas de Tipagem Bacteriana , Cavidade Pulpar/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Enterococcus/isolamento & purificação , Exsudatos e Transudatos/microbiologia , Feminino , Bactérias Gram-Negativas/isolamento & purificação , Cocos Gram-Positivos/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Streptococcus/isolamento & purificação
12.
J Endod ; 26(4): 221-4, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11199722

RESUMO

Intracanal exudates in persistent endodontic cases were sampled for detecting bacteria using a preculture method, and the antibiotic susceptibility of the bacteria identified was examined. Twelve species were recovered from 15 cases. The species most commonly detected were alpha-Streptococcus and Enterococcus. The results of the antibiotic susceptibility tests revealed that Enterococcus was highly resistant to antibiotics tested, especially to cephalosporin products. Enterococcus is known as one of the bacteria that show multidrug resistance. In cases of prolonged endodontic treatment, a specific antibiotic prescription would play an important role for efficient treatment. Collecting data about antibiotic susceptibility could be helpful. Identification, however, take approximately 2 wk and a further study to develop the method that rapidly informs us about the antibiotic susceptibility that might be needed.


Assuntos
Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Cavidade Pulpar/microbiologia , Periodontite Periapical/microbiologia , Resistência às Cefalosporinas , Doença Crônica , Resistência Microbiana a Medicamentos , Resistência a Múltiplos Medicamentos , Enterococcus/efeitos dos fármacos , Exsudatos e Transudatos/microbiologia , Feminino , Humanos , Masculino , Resistência às Penicilinas , Tratamento do Canal Radicular , Streptococcus/efeitos dos fármacos , Fatores de Tempo , Resultado do Tratamento
13.
Arch Oral Biol ; 42(2): 185-8, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9134131

RESUMO

It has been reported that the mandibular body and the dental arch distort during jaw movements because of contraction of the jaw muscles. In the present study the relative position between two biointegrated implants approx. 10 mm apart was measured during maximum opening and protrusive movements of the jaw using a magnetic sensor system. Mandibular distortion was evaluated as the change in the sensor signal. In all participants the distal implant deviated to the lingual side relative to the mesial implant and the deviation with jaw protrusion was larger than that with opening movement. The linear displacement of the two implants ranged from 8 to 25 microns during maximum opening and from 10 to 37 microns during jaw protrusion. Further investigation is required to establish the mechanism of this mandibular distortion, which may be of relevance to implant therapy.


Assuntos
Implantes Dentários , Mandíbula/fisiologia , Músculos da Mastigação/fisiologia , Adulto , Análise do Estresse Dentário , Elasticidade , Feminino , Humanos , Magnetismo , Masculino , Pessoa de Meia-Idade , Movimento , Processamento de Sinais Assistido por Computador , Estresse Mecânico
14.
Dent Mater ; 17(4): 333-9, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11356210

RESUMO

OBJECTIVES: The aim of this study was to examine the relationship between the monomers eluted from dentin-bonding systems and their cytotoxicities, and to investigate the biochemical effect of the monomers on tyrosine phosphorylation, especially relating to the cell growth activity, of L929 cells in vitro. METHODS: The primers, uncured or cured adhesives (3M and Kuraray) were tested to determine the cytotoxicity of confluent L929 cells cultured by Eagle's MEM medium supplemented with 10% FCS. The area of cells affected by the eluted monomers were evaluated with an image analyzer and the concentrations of monomers eluted into the medium were measured with high performance liquid chromatography (HPLC) after 24h incubation. The protein composition of the stimulated cells was compared by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and tyrosine phosphorylation was detected by Western blot. RESULTS: The primer and uncured adhesives revealed variable cytotoxicities. 2-hydroxyethyl-methacrylate (HEMA) was the major component eluted from uncured primers and adhesives. Small amounts of triethylene glycol dimethacrylate (TEGDMA) were also detected from the uncured adhesives. The cytotoxicities of the adhesives decreased as photo activation time increased. The amount of monomers eluted from the cured adhesives was almost undetectable and did not reach a sufficient concentration to suppress cell viability or cell growth. The cytotoxicities of the primers and adhesives correlated well with the amounts of either HEMA or TEGDMA eluted. Moreover, a high concentration of HEMA (4 mg/ml medium) affected intracellular tyrosine phosphorylation, which is related to cellular activities. SIGNIFICANCE: Although the monomers present in dentin bonding resins are cytotoxic to L929 cells, the amount from cured bonding resin is very small and does not provide a cytotoxic dose. This data does however suggest that clinical exposure to the uncured primers and adhesives of dentin bonding resins should be minimized.


Assuntos
Adesivos Dentinários/toxicidade , Fibroblastos/efeitos dos fármacos , Proteínas Tirosina Fosfatases/efeitos dos fármacos , Pele/efeitos dos fármacos , Tirosina/efeitos dos fármacos , Adesivos/toxicidade , Análise de Variância , Animais , Western Blotting , Contagem de Células , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Resinas Compostas/toxicidade , Eletroforese em Gel de Poliacrilamida , Processamento de Imagem Assistida por Computador , Luz , Teste de Materiais , Metacrilatos/toxicidade , Camundongos , Fosforilação , Polietilenoglicóis/toxicidade , Ácidos Polimetacrílicos/toxicidade , Proteínas Tirosina Fosfatases/análise , Cimentos de Resina/toxicidade , Pele/citologia , Tirosina/análise
16.
J Oral Rehabil ; 35(2): 105-10, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18197843

RESUMO

Blue light curing units (wavelengths of 400-500 nm) are a mainstay of restorative dentistry, and several high-intensity light sources have been developed to polymerize resin composites more rapidly. The biological safety of visible light has been assumed, but some reports of adverse biological effects of blue light in non-dental contexts support further evaluation of the biological safety of high-intensity blue light. The current study tested the hypothesis that blue light provokes cell stress responses resulting in the secretion of cytokines or expression of heat-shock proteins (HSP) in monocytes. Human monocytic cells were irradiated with three light sources (quartz-tungsten-halogen, plasma-arc and laser), then cellular proliferation, secretion of the inflammatory cytokine TNFalpha and induction of HSP72 were measured. Results indicated that although all three light sources significantly inhibited proliferation of monocytes, the secretion of TNFalpha was not induced following exposure to blue light and was not potentiated with administration of the activator lipopolysaccharide. Similarly, treatment with the plasma-arc light, which caused the largest temperature increase in previous studies, did not induce HSP72. The current results do not support activation of monocytes by blue light as an inflammatory risk factor in dental tissues during curing of composites. However, the results of the current study should be further verified in primary monocytes and an animal model before decisions about clinical risks are made.


Assuntos
Resinas Compostas , Colagem Dentária/métodos , Luz/efeitos adversos , Monócitos/efeitos da radiação , Proliferação de Células/efeitos da radiação , Células Cultivadas , Proteínas de Choque Térmico HSP72/metabolismo , Halogênios , Humanos , Lasers/efeitos adversos , Monócitos/imunologia , Monócitos/metabolismo , Quartzo , Tecnologia Odontológica , Temperatura , Fator de Necrose Tumoral alfa/metabolismo , Tungstênio
17.
Nihon Shishubyo Gakkai Kaishi ; 31(2): 593-607, 1989 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-2637302

RESUMO

Dental radiographs can be important for examination, evaluation and diagnosis of periodontal disease, and they have been widely used by dentists. However, discrepancies between radiographs and existing clinical periodontal tissue have been found. The purpose of this study was to investigate the relationship between the existing alveolar bone level on a Xeroradiograph and the root surface area covered with a periodontal ligament. Alveolar bone blocks from human skulls (total 34 teeth) and 60 patients (total 165 teeth) were used for this study. Each human skull bone block was taken Xeroradiograph under three types of conditions. 165 teeth from patients with severe periodontal disease were taken Xeroradiograph by a parallel method. The following equation was used for measuring the teeth on the Xeroradiograph. alpha = Root area supporting the existing alveolar bone/Root area from periapical to C-E junction x 100 The root surface area of each of the teeth extracted from bone blocks and of the extracted teeth from patients were measured by the membrane technique and calculated as follows: beta = Root surface area covered with periodontal ligament/Root surface area x 100 There was no significant difference in equation alpha calculated on three types of Xeroradiographs in the human skull. Significant positive correlations between alpha and beta were obtained, and an empirical regression line was constructed to estimate the ratio of the root surface area covered with periodontal ligament from the existing alveolar bone level on the Xeroradiograph. The results suggest that the ratio of the area of periodontal ligament to the root surface area given by these methods provides useful data for examination, diagnosis and evaluation of periodontal disease.


Assuntos
Processo Alveolar/diagnóstico por imagem , Xerorradiografia , Humanos , Ligamento Periodontal/anatomia & histologia , Raiz Dentária/anatomia & histologia
18.
Prep Biochem Biotechnol ; 29(4): 333-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10548250

RESUMO

Mono-, di-, and tetraalkyl tin(IV) compounds were evaluated for the intramolecular transesterification reaction of the thermal depolymerization of poly(L-lactic acid) oligomer forming lactide by gas chromatography using a beta-cyclodextrin stationary phase capillary column. The most active catalyst was found to be monobutyltin trichloride (BuSnCl3) (8), which contains tin-halogen bonds, and the least effective was the coordinatively saturated monoorganotin derivative, monobutyltin tris(2-ethylhexanoate) (7). Coordination of the carbonyl group in the oligomer to the tin catalysts is an important factor influencing its activity.


Assuntos
Ácido Láctico/química , Compostos Orgânicos de Estanho/química , Polímeros/química , Catálise , Cromatografia Gasosa , Esterificação , Poliésteres
19.
Microbiol Immunol ; 44(11): 923-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11145273

RESUMO

IgA has been supposed to play an important role in the prevention of HIV-1 infection. In this study, IgA-binding sites on gp120 and gp41 of HIV-1 envelope glycoproteins were analyzed using ELISA and overlapping synthetic peptides covering all of the gp120 and gp41 sites. IgA antibodies in plasma and saliva mainly bound to six and five sites on gp120 and gp41, respectively. Some of the IgA-binding sites differed from those of IgG-binding sites and the amount of IgA antibodies that bound to each site varied among samples. IgA antibodies in some plasma samples neutralized HIV-1 infection, and those IgA antibodies contained the antibodies which bound to the V3, C3 and ELDKWA sites. The results suggest that IgA antibodies which bind to certain sites on HIV-1 envelope glycoproteins may neutralize HIV-1 infection, presumably at mucosal sites where most IgA antibodies are produced. The induction of IgA antibodies that bind specific sites and neutralize HIV-1 infection at mucosal sites may be important in the development of a vaccine against HIV-1 infection.


Assuntos
Epitopos/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , HIV-1/imunologia , Imunoglobulina A Secretora/imunologia , Imunoglobulina A/imunologia , Sequência de Aminoácidos , Reações Antígeno-Anticorpo , Sítios de Ligação , Sítios de Ligação de Anticorpos , Ensaio de Imunoadsorção Enzimática , Proteína gp120 do Envelope de HIV/química , Proteína gp41 do Envelope de HIV/química , Infecções por HIV/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Dados de Sequência Molecular , Testes de Neutralização , Fragmentos de Peptídeos/imunologia , Proteínas Recombinantes/imunologia , Saliva/imunologia
20.
Acta Pathol Jpn ; 30(1): 145-56, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7361547

RESUMO

A granular cell ameloblastoma occurring in the anterior mandible of a 49-year-old woman has been studied both histologically and ultrastructurally. Histologically the tumor in this case showed a mixed type of follicular, granulal cell, and acanthomatous type of ameloblastoma. Many granular cells seemed to gather around the periphery of each tumor island. Electron-microscopically the cytoplasmic granules were measured as approximately 0.6 mu in diameter, and were surrounded by limiting membrane. Most of these granules revealed high electron density and their contents showed various patterns--osmiophilic homogeneous, fingerprint, and small particles--and were identified as lysosomes. However, no enamel matrix precursor was identified in either lysosome or cytoplasm. All the granular cells showed regular nuclei and no degeneration. Though lysosomes might play a role of autophagy and of remodeling the cytoplasm, its presence seems to have an active function in tumor cells, as opposed to the aging or degenerating function.


Assuntos
Ameloblastoma/ultraestrutura , Neoplasias Mandibulares/ultraestrutura , Feminino , Humanos , Pessoa de Meia-Idade
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