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1.
J Clin Epidemiol ; 139: 287-296, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34091021

RESUMO

OBJECTIVE: We aimed to map the resource use during systematic review (SR) production and reasons why steps of the SR production are resource intensive to discover where the largest gain in improving efficiency might be possible. STUDY DESIGN AND SETTING: We conducted a scoping review. An information specialist searched multiple databases (e.g., Ovid MEDLINE, Scopus) and implemented citation-based and grey literature searching. We employed dual and independent screenings of records at the title/abstract and full-text levels and data extraction. RESULTS: We included 34 studies. Thirty-two reported on the resource use-mostly time; four described reasons why steps of the review process are resource intensive. Study selection, data extraction, and critical appraisal seem to be very resource intensive, while protocol development, literature search, or study retrieval take less time. Project management and administration required a large proportion of SR production time. Lack of experience, domain knowledge, use of collaborative and SR-tailored software, and good communication and management can be reasons why SR steps are resource intensive. CONCLUSION: Resource use during SR production varies widely. Areas with the largest resource use are administration and project management, study selection, data extraction, and critical appraisal of studies.


Assuntos
Coleta de Dados , Relatório de Pesquisa , Revisões Sistemáticas como Assunto , Humanos , Pesquisa Biomédica/normas , Pesquisa Biomédica/estatística & dados numéricos , Coleta de Dados/métodos , Coleta de Dados/normas , Coleta de Dados/estatística & dados numéricos , Projetos de Pesquisa , Relatório de Pesquisa/normas , Revisões Sistemáticas como Assunto/métodos , Revisões Sistemáticas como Assunto/normas
2.
Int J Cosmet Sci ; 40(4): 420-424, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29846953

RESUMO

BACKGROUND: The physiopathology of epidermal hypermelanization in melasma is not completely understood. Several cytokines and growth factors are increased in skin with melasma, nevertheless, nor the pathways involved in the increased αMSH expression have been adequately evaluated, nor a model for sustained focal melanogenesis is available. OBJECTIVE: To explore stimulatory pathways for epidermal pigmentation in facial melasma related to αMSH: those linked to ultraviolet radiation, oxidative stress, inflammation, neural crest pigmentation cell differentiation and antagonism of αMSH. METHODS: Paired skin biopsies (3 mm) from 26 women with facial melasma and from normal adjacent skin (<2 cm far) were processed for immunofluorescence with markers for p53, p38, αMSH, MC1R, Melan-A, IL-1α, COX2, Wnt1, WIF-1 and ASIP. RESULTS: The fluorescence intensity in the skin from melasma was higher for MC1R, αMSH at epidermis as at melanocytes (P < 0.05). There were no differences between the sites in epidermal protein expression of COX2, IL-1α, p53, WIF-1 and ASIP (P > 0.1). P53 was expressed only in epidermis, without difference between sites (P = 0.92). WNT1 was remarkable in the epidermis of melasma (P < 0.01), but not in dermis. Positive p38 cells were prominent in the upper dermis of melasma (P < 0.01), despite no marking in epidermis. CONCLUSION: Melanogenesis in melasma involves epithelial secretion of αMSH and activation of the Wnt pathway; nevertheless, it seems to be independent of the stimulation by ultraviolet radiation/p53, IL-1α, COX2/PgE2 , WIF-1 and ASIP. Damaged cells at upper dermis suggest the role of senescence/autophagy in sustained pigmentation in melasma.


Assuntos
Face , Melaninas/biossíntese , Melanose/metabolismo , Adulto , Biomarcadores/metabolismo , Biópsia , Diferenciação Celular , Estudos Transversais , Feminino , Imunofluorescência , Humanos , Mediadores da Inflamação/metabolismo , Melanose/patologia , Pessoa de Meia-Idade , Estresse Oxidativo , Raios Ultravioleta
3.
Arq. bras. med. vet. zootec. (Online) ; 70(4): 1179-1186, jul.-ago. 2018. tab, ilus, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-946399

RESUMO

Para comparar a regeneração tecidual de feridas dérmicas em coelhos tratados e não tratados, de forma seriada, com diferentes fontes de plasma rico em plaquetas (PRP) gel, biópsias dérmicas foram feitas na região dorsal, com auxílio de um punch de 8mm, em que o lado direito foi tratado com NaCl 0,9%® e o lado esquerdo recebeu aplicação de diferentes fontes de PRPs (autóloga, heteróloga e homóloga), nos dias zero, três, sete, 10, 14, tendo sido acompanhadas durante 17 dias. Ao final do 17º dia, foi realizada avaliação histopatológica das feridas. Do total de 24 animais, seis coelhos (três machos e três fêmeas) foram utilizados somente como doadores para obtenção do PRP homólogo gel. Um cão adulto, saudável, foi utilizado como doador durante o experimento para o preparo do PRP gel do grupo heterólogo. As médias das fibras dos grupos autólogo e homólogo foram muito semelhantes (75,0±13,7 e 73,1±10,2, respectivamente), quando comparadas às médias obtidas no grupo controle (71,5±10,8). Já as fibras colágenas do grupo heterólogo foram inferiores (P<0,05) às dos demais grupos (59,4±11,3). Conclui-se que a fonte heteróloga produz fibras colágenas menos organizadas e menos homogêneas, sendo o último recurso a ser utilizado para promover uma cicatrização de boa qualidade.(AU)


In order to compare the tissue regeneration of dermal wounds in treated and untreated rabbits serially with different sources of platelet rich plasma (PRP) gel, dermal biopsies were made in the dorsal region with the aid of an 8mm punch. The right side was treated with 0.9% NaCl and, on the left side, the different sources of PRPs (autologous, heterologous and homologous) on days 0, 3, 7, 10, 14 were applied and monitored for 17 days. At the end of the 17th day, histopathological evaluation of the wounds was performed. From the total of 24 animals, six rabbits (3 males and 3 females) were used only as donors to obtain the homologous PRP gel. A healthy, adult dog was used as a donor during the experiment to prepare the PRP gel from the heterologous group. The mean values of the fibers of the autologous and homologous groups were very similar (75.0±13.7 and 73.1±10.2, respectively), when compared to the means obtained in the control group (71.5±10.8). The collagen fibers of the heterologous group were inferior (P<0.05) to the other groups (59.4±11.3). It is concluded that the heterologous source produces less organized and homogeneous collagen fibers and should be the last resource to be used in order to promote good quality healing.(AU)


Assuntos
Animais , Coelhos , Colágeno/análise , Fibrina Rica em Plaquetas , Cicatrização , Ferimentos e Lesões/enzimologia
4.
Int J Cosmet Sci ; 38(6): 651-654, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27163333

RESUMO

OBJECTIVE: The objective of this study is to evaluate apoptosis in hair follicles of patients with female pattern hair loss (FPHL) and its association with follicular microinflammation. METHOD: Cross-sectional study involving 17 women with FPHL and five controls. Scalp skin samples were processed for HE and TUNEL assays. The variables were compared according to the categories of follicles (terminal versus miniaturized) and groups of patients (FPHL vs. controls). RESULTS: There was a higher apoptosis index among miniaturized follicles and among the test cases (P < 0.01). Microinflammation was prominent among miniaturized follicles, especially from FPHL (P = 0.02). In addition, a positive correlation between inflammatory infiltrate and apoptosis in miniaturized follicles (rS = 0.68; P < 0.01) was found. CONCLUSIONS: Apoptosis was prominent in hair follicles from the FPHL group, as well as in miniaturized ones. Moreover, it was also correlated with the inflammatory infiltrate, which suggests that inflammation can lead to apoptosis and play a role in the pathogenesis of follicle miniaturization.


Assuntos
Alopecia/patologia , Apoptose , Folículo Piloso/patologia , Inflamação/patologia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Marcação In Situ das Extremidades Cortadas
5.
Int J Cosmet Sci ; 37(2): 222-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25439299

RESUMO

OBJECTIVE: Compare gene and protein expression for oestrogen receptor-ß (ER-ß) and progesterone receptor (PR) in facial melasma and adjacent healthy skin. METHODS: A cross-sectional study including 42 women with facial melasma, conducted at the Dermatology Service of Botucatu Medical School of São Paulo State University, Brazil. Biopsies of the melasma skin were performed, together with healthy surrounding skin. The gene expression (real-time PCR) of the hormone receptors in the tissue was evaluated. Subsequently, skin fragments were immunostained for nuclear ER-ß and PR, evaluated according to their HSCORE (epidermis) and percentage of staining per microscopic field (dermis). RESULTS: Messenger RNA tissue expression for ER-ß and PR showed no difference between melasma-affected skin fragments and the healthy perilesional areas (P > 0.2). Median nuclear epithelial expression for ER-ß and PR was higher in lesioned skin (HSCORE 157 and 58) than in the healthy perilesional skin (HSCORE 97 and 19; P < 0.01), with no difference in dermal immunostaining. Nuclear histological expression for ER-ß was associated to sun-induced melasma and negative familiar background; PR expression was associated to sun-induced melasma and darker phototypes. CONCLUSION: No difference was observed in gene expression for oestrogen-ß and progesterone receptors in melasma-affected skin compared with adjacent healthy skin. However, the higher protein expression of these receptors in melasma-affected epithelia suggests hormonal participation in the pathogenesis of this disease.


Assuntos
Receptor beta de Estrogênio/metabolismo , Face , Melanose/metabolismo , Receptores de Progesterona/metabolismo , Pele/metabolismo , Adulto , Estudos Transversais , Receptor beta de Estrogênio/genética , Feminino , Humanos , Receptores de Progesterona/genética
6.
J Eur Acad Dermatol Venereol ; 27(2): 151-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22212073

RESUMO

UNLABELLED: BACKGROUND; Melasma is a common acquired chronic hypermelanosis of sun-exposed areas which significantly impacts quality of life. There are few epidemiological studies in medical literature concerning these patients. OBJECTIVE: Characterize clinical and epidemiological data on Brazilian female patients with melasma. METHODS: A semi-structured questionnaire was administered to melasma patients treated at a dermatology clinic between 2005 and 2010. Association between variables was performed by multivariate regression models. RESULTS: We assessed 302 patients; intermediate skin phototypes III (34.4%) and IV (38.4%) were prevalent. Mean disease onset age was 27.5 ± 7.8 years and familiar occurrence of melasma was identified in 56.3%. The most commonly reported trigger factors were pregnancy (36.4%), contraceptive pills (16.2%) and intense sun exposure (27.2%). Preferred facial topographies were zygomatic (83.8%), labial superior (51.3%) and frontal (49.7%). Pregnancy induced melasma has been associated to early disease (OR = 0.86) and number of pregnancies (OR = 1.39). Childbearing was correlated to melasma extension. Older disease onset age was associated to darker skin phototypes. Co-occurrence of facial topographies supported clinical classification as centrofacial and peripheral melasma. CONCLUSION: This population was characterized by: a high prevalence in adult females, intermediate skin phototypes, disease precipitation by hormonal stimulus and familiar genetic influence.


Assuntos
Face , Melanose/epidemiologia , Adulto , Brasil/epidemiologia , Feminino , Humanos , Hidrocortisona/sangue , Melanose/patologia , Gravidez , Tireotropina/sangue , Adulto Jovem
7.
Trans R Soc Trop Med Hyg ; 105(8): 473-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21684567

RESUMO

The identification of appropriate laboratory measures to confirm clinical hypotheses is important in routine paracoccidioidomycosis medical care. The clinical records and laboratory reports of 401 paracoccidioidomycosis patients attended at the Tropical Diseases Area, Faculdade de Medicina de Botucatu, from 1974 to 2008 were reviewed. Direct mycological (DM), cell block (CB), histopathological (HP), and double immunodiffusion (DID) tests were evaluated before treatment. Typical Paracoccidioides brasiliensis yeast forms were observed in clinical specimens of 86% of the patients, but 14% were detected only by serological test. DM of 51 different tissue specimens produced 74.5% sensitivity, and 62.5% sensitivity was observed in 112 sputum samples. CB in 483 sputum samples generated 55.3% sensitivity. HP performed in 239 samples from different tissues revealed 96.7% sensitivity. Serology carried out in 351 patients and 200 healthy controls provided 90.0% sensitivity, 100.0% specificity, 100.0% positive predictive value, 85.1% negative predictive value and 93.6% accuracy. Comparisons of laboratory measurements performed in the same patient showed that sensitivity decreases from HP to DID to CB and DM, with the last two assays providing similar sensitivities. This study demonstrated that P. brasiliensis identification by HP, CB, and/or DM associated with DID is sufficient to establish the laboratorial diagnosis of paracoccidioidomycosis in practically all cases.


Assuntos
Imunodifusão , Paracoccidioides/isolamento & purificação , Paracoccidioidomicose/imunologia , Escarro/imunologia , Adulto , Brasil/epidemiologia , Testes Diagnósticos de Rotina , Feminino , Hospitais Universitários , Humanos , Imunodifusão/métodos , Masculino , Pessoa de Meia-Idade , Paracoccidioidomicose/diagnóstico , Paracoccidioidomicose/epidemiologia , Estudos Retrospectivos
8.
Arq. bras. med. vet. zootec ; 59(6): 1462-1467, dez. 2007. ilus
Artigo em Português | LILACS | ID: lil-476117

RESUMO

Avaliaram-se as alterações relacionadas à deficiência das células límbicas precursoras do epitélio corneano de coelhos e o efeito da membrana amniótica sobre sua cicatrização. A lesão, induzida com n-heptanol associado à peritomia conjuntival em 360º, foi recoberta com membrana amniótica canina, suturada à episclera perilímbica, criopreservada em meio para congelação de embrião ou em meio próprio, ambos com glicerol a 50 por cento e mantida a -80ºC. O grupo-controle não foi tratado com a membrana. As avaliações histológicas foram realizadas ao sétimo, 15º e 30º dias. Todos desenvolveram deficiência de células germinativas do limbo, denominada conjuntivalização, com presença de neovascularização, inflamação e defeitos epiteliais recorrentes, caracterizada na histopatologia pela presença de neovasos, edema, leucócitos e células caliciformes. O transplante de membrana amniótica não foi eficiente para o tratamento desta deficiência, entretanto auxiliou o processo de cicatrização da córnea


Changes related to limbal stem cells deficiency in corneal epithelium in rabbits, as well as the results of amniotic membrane transplant on the cicatrisation were evaluated. The ulcer was induced with n-heptanol associated to 360º conjunctival peritomy; the corneal surface was covered with canine amniotic membrane, sutured to perilimbal episclera, cryopreserved in embryo solution or own medium, both with 50 percent glycerol and stored at -80ºC. The control group was not treated with membrane. Histological evaluations were performed at seven, 15, and 30 days. All of them developed limbal stem cells deficiency, named conjunctivalization, with neovascularization, inflammation and recurrent epithelial defects, observed in histopathology by the occurrence of neovascularization, edema, leukocytes and goblet cells. Thus amniotic membrane transplantation was not efficient in the treatment of limbal stem cells deficiency, however it helped in the process of cicatrisation


Assuntos
Animais , Cães , Coelhos , Âmnio/transplante , Cicatrização/fisiologia , Córnea/cirurgia , Criopreservação/veterinária
10.
Caries Res ; 41(3): 239-43, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17426407

RESUMO

The goal of this study was to investigate the ability of fluoride to modulate the genotoxic effects induced by the oxidative agent hydrogen peroxide (H2O2) and the alkylating agent methyl methanesulfonate (MMS) in vitro by the single-cell gel (comet) assay. Chinese hamster ovary cells were exposed in culture for 1 h at 37 degrees C to sodium fluoride at 7-100 microg/ml. NaF-treated and control cells were then incubated with 0-10 microM MMS in phosphate-buffered saline (PBS) for 15 min at 37 degrees C, or 0-100 microM H2O2 in distilled water for 5 min on ice. Negative control cells were treated with PBS for 1 h at 37 degrees C. Clear concentration-related effects were observed for the two genotoxins. Increase of DNA damage induced by either MMS or H2O2 was not significantly altered by pretreatment with NaF. The data indicate that NaF does not modulate alkylation-induced genotoxicity or oxidative DNA damage as measured by the single-cell gel (comet) assay.


Assuntos
Alquilantes/toxicidade , Cariostáticos/farmacologia , Dano ao DNA/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Metanossulfonato de Metila/toxicidade , Oxidantes/toxicidade , Fluoreto de Sódio/farmacologia , Animais , Células CHO , Ensaio Cometa , Cricetinae , Cricetulus , Estatísticas não Paramétricas
11.
Int J Hyg Environ Health ; 210(2): 163-7, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17084670

RESUMO

Since chlorhexidine is effective against microorganisms, it is widely recommended in dentistry. However, studies have provided evidence that chlorhexidine is toxic for a variety of cell types. In order to identify potential genotoxins in different cell types, the purpose of this study was to investigate whether chlorhexidine digluconate is able to cause, in terms of DNA damage, alterations in leukocytes, liver, kidney and urinary bladder by the single cell gel (comet) assay. Ten male Wistar rats were divided into two groups: a negative control and the experimental group treated with 3ml of 0.12% chlorhexidine digluconate by gavage once a day for 8 days. Statistically significant increases of DNA damage was observed in leukocytes and kidney cells of the chlorhexidine digluconate treated group as depicted by the mean tail moment. Taken together, the data indicate that leukocytes and kidney cells are potential targets for primary DNA damage following oral exposure to chlorhexidine digluconate as detected by single cell gel (comet) assay.


Assuntos
Clorexidina/efeitos adversos , Dano ao DNA , DNA/efeitos dos fármacos , Desinfetantes/efeitos adversos , Animais , DNA/sangue , Masculino , Testes de Mutagenicidade , Ratos , Ratos Wistar , Vísceras
13.
J Oral Rehabil ; 33(12): 912-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17168933

RESUMO

Glass-ionomer cements are widely used in dentistry as restorative materials and adhesives for composite restorations. A number of genotoxicity studies have been conducted using these materials with results conflicting so far. Thus, the approach was aimed to look at the genotoxic and cytotoxic potential of three different glass-ionomer cements available commercially (Ketac Cem, Ketac Molar and Vitrebond) by the single cell gel (comet) assay and trypan blue exclusion test, respectively. For this, such materials were exposed to mouse lymphoma cells in vitro for 1 h at 37 degrees C. Data were assessed by Kruskall-Wallis non-parametric test. The results showed that all powders assayed did not show genotoxic effects. On the other hand, the liquid from Vitrebond at 0.1% dilution caused an increase of DNA injury. Significant statistically differences (P < 0.05) in cytotoxicity provoked by all powders tested were observed for exposure at 1,000 micro g mL(-1) concentration and 100 micro g mL(-1) for Ketac Molar. With respect to liquids of glass-ionomer cements evaluated, the major toxic effect on cell viability was produced at 1%, beginning at the dilution of 0.5% for Vitrebond. Taken together, these results support the notion that some components of glass-ionomer cements show both genotoxic and cytotoxic effects in higher concentrations.


Assuntos
Dano ao DNA , Materiais Dentários/toxicidade , Cimentos de Ionômeros de Vidro/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Leucemia L5178 , Óxido de Magnésio/toxicidade , Teste de Materiais , Camundongos , Cimento de Policarboxilato/toxicidade , Estatísticas não Paramétricas , Azul Tripano , Óxido de Zinco/toxicidade
14.
Med Mycol ; 44(7): 671-6, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17071564

RESUMO

A 49-year-old renally transplanted man, under a five-year course of immunosuppressive therapy with prednisone and cyclosporine A, experienced a subcutaneous phaeohyphomycosis caused by Phaeoacremonium parasiticum. The clinical presentation consisted of impressive, large, inflammatory and draining cystic tumors on the left foot that had been present for one year. A significant improvement was obtained with itraconazole plus intralesional injection with amphotericin B. Drug interaction was observed between itraconazole and cyclosporine A causing a severe hypertensive crisis and requiring a temporary sharp reduction in cyclosporine administration. Subcutaneous phaeohyphomycosis caused by P. parasiticum is uncommon among major organ transplant patients but several cases have previously been published and some patterns are emerging, e.g., limbs are generally involved but no known traumatic event has preceded lesion development. The identification of the case isolate was confirmed using a recently published online system based in part on beta-tubulin sequence comparison.


Assuntos
Ascomicetos/isolamento & purificação , Dermatomicoses/microbiologia , Hospedeiro Imunocomprometido , Transplante de Rim/efeitos adversos , Anfotericina B/uso terapêutico , Antifúngicos/uso terapêutico , Dermatomicoses/patologia , Dermatomicoses/terapia , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Pele/microbiologia , Pele/patologia
15.
Br J Dermatol ; 154(4): 643-50, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16536806

RESUMO

BACKGROUND: Mucocutaneous lesions in paracoccidioidomycosis are granulomatous and result from tissue responses to Paracoccidioides brasiliensis, the aetiological agent. OBJECTIVES AND METHODS: In this study we investigate the expression of tumour necrosis factor (TNF)-alpha, interleukin (IL)-10 and transforming growth factor (TGF)-beta1 by immunohistochemistry in skin and mucosa lesions from patients with the chronic form of paracoccidioidomycosis, evaluated before and at day 20 of trimethoprim-sulfamethoxazole treatment. Cytokine production by peripheral blood monocytes was also studied by enzyme immunoassay. RESULTS: Intense immunostaining for TNF-alpha was detected in mononuclear cells that infiltrated granulomas in all skin and mucosa lesions before treatment simultaneously with low IL-10 granular deposits in these cells. At day 20 of treatment, there was reduced TNF-alpha and IL-10 deposition. Immunoreactive TGF-beta1 was observed diffusely in the dermis and generally in the cytoplasm of macrophages and giant cells, before treatment, and as increased TGF-beta1 deposits in the fibrosis area at day 20 of treatment. Peripheral blood monocytes from patients with paracoccidioidomycosis, evaluated before treatment, produced high endogenous levels of TNF-alpha, TGF-beta1 and IL-10 in relation to healthy controls. Lipopolysaccharide-stimulated monocytes from patients secreted lower levels of TNF-alpha in both periods of evaluation while no impairment in capacity of IL-10 and TGF-beta production was observed. CONCLUSIONS: Trimethoprim-sulfamethoxazole therapy was effective in decreasing fungal load in the lesions, allowing patient immune response to control the infection leading to the healing of the lesions.


Assuntos
Antifúngicos/uso terapêutico , Citocinas/metabolismo , Monócitos/imunologia , Paracoccidioidomicose/imunologia , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Adulto , Idoso , Células Cultivadas , Citocinas/biossíntese , Feminino , Humanos , Técnicas Imunoenzimáticas , Interleucina-10/metabolismo , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/imunologia , Mucosa Bucal/patologia , Paracoccidioidomicose/tratamento farmacológico , Paracoccidioidomicose/patologia , Pele/imunologia , Pele/patologia , Fator de Crescimento Transformador beta/metabolismo , Fator de Crescimento Transformador beta1 , Fator de Necrose Tumoral alfa/metabolismo
16.
J Oral Rehabil ; 33(3): 234-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16512891

RESUMO

summary Mineral trioxide aggregate (MTA) and Portland cement are being used in dentistry as root-end-filling material for periapical surgery and for the sealing of communications between the root canal system and the surrounding tissues. However, genotoxicity tests for complete risk assessment of these compounds have not been conducted up to now. In the present study, the genotoxic effects of MTA and Portland cements were evaluated in peripheral lymphocytes from 10 volunteers by the alkaline single cell gel (comet) assay. The results pointed out that the single cell gel (comet) assay failed to detect the presence of DNA damage after a treatment of peripheral lymphocytes by MTA and Portland cements for concentrations up to 1000 mug mL(-1). In summary, our results indicate that exposure to MTA or Portland cements may not be a factor that increases the level of DNA lesions in human peripheral lymphocytes as detected by single cell gel (comet) assay.


Assuntos
Compostos de Alumínio/farmacologia , Compostos de Cálcio/farmacologia , Dano ao DNA/genética , DNA/efeitos dos fármacos , Cimentos Dentários/farmacologia , Linfócitos/efeitos dos fármacos , Óxidos/farmacologia , Silicatos/farmacologia , Adulto , Células Cultivadas , Ensaio Cometa/métodos , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Feminino , Humanos , Masculino , Materiais Restauradores do Canal Radicular/farmacologia
17.
Int Endod J ; 39(1): 26-30, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16409325

RESUMO

AIM: To examine the genotoxicity and cytotoxicity of regular and white mineral trioxide aggregate (MTA) ex vivo by the single-cell gel (comet) assay and trypan blue exclusion test, respectively. METHODOLOGY: Aliquots of 1 x 10(4) Chinese hamster ovary cells were incubated at 37 degrees C for 3 h with grey and white forms of MTA at final concentrations ranging from 1 to 1,000 microg mL(-1). The negative control group was treated with vehicle control phosphate buffer solution for 3 h at 37 degrees C and the positive control group was treated with methyl metasulfonate (at 1 microg mL(-1)) for 1 h at 37 degrees C. After incubation, the cells were centrifuged at 180 g for 5 min and washed twice with fresh medium and resuspended with fresh medium. Each individual treatment was repeated three times consecutively to ensure reproducibility. Parameters from single-cell gel (comet) and cytotoxicity assays were assessed by the Kruskal-Wallis nonparametric test. RESULTS: Neither compounds produced genotoxic effects with respect to the single-cell gel (comet) assay in all concentrations evaluated. In the same way, the dose-response relationships of all compounds tested at concentrations ranging from 1 to 1,000 microg mL(-1) on cell viability assessed by the trypan blue assay displayed no statistically significant differences (P > 0.05) for either endodontic material. CONCLUSIONS: Regular (grey) and white MTA are not genotoxins and do not induce cellular death.


Assuntos
Compostos de Alumínio/toxicidade , Compostos de Cálcio/toxicidade , Teste de Materiais/métodos , Óxidos/toxicidade , Materiais Restauradores do Canal Radicular/toxicidade , Silicatos/toxicidade , Animais , Ensaio Cometa/métodos , Cricetinae , Combinação de Medicamentos , Feminino , Ovário/citologia , Ovário/efeitos dos fármacos
18.
J Oral Rehabil ; 32(10): 766-71, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16159356

RESUMO

Dental bleaching is a simple and conservative procedure for aesthetic restoration of vital discoloured teeth. However, dental bleaching agents may represent a hazard to human health, especially by causing DNA strand breaks. Genotoxicity tests form an important part of cancer research and risk assessment of potential carcinogens. In the current study, the genotoxic potential associated with exposure to dental bleaching agents was assessed by the single cell gel (comet) assay in vitro. Six commercial dental bleaching agents (Clarigel Gold - Dentsply; Whitespeed - Discus Dental; Nite White - Discus Dental; Magic Bleaching - Vigodent; Whiteness HP - FGM and Lase Peroxide - DMC) were exposed to mouse lymphoma cells in vitro. The results pointed out that all dental bleaching agents tested contributed to the DNA damage as depicted by the mean tail moment. Clear concentration-related effects were obtained for DNA damaging, being the strongest effect observed at the highest dose of the hydrogen peroxide (Whiteness HP and Lase Peroxide, at 35% concentration). On the contrary, Whitespeed (Discus Dental) induced the lowest level of DNA breakage. Taken together, these results suggest that dental bleaching agents may be a factor that increases the level of DNA damage as detected by the single cell gel (comet) assay.


Assuntos
Linfoma/genética , Clareamento Dental , Animais , Sobrevivência Celular , Células Cultivadas , Ensaio Cometa/métodos , Dano ao DNA/efeitos dos fármacos , Peróxido de Hidrogênio/toxicidade , Linfoma/patologia , Camundongos , Testes de Mutagenicidade , Polimetil Metacrilato
19.
Caries Res ; 38(6): 576-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15528915

RESUMO

Fluoride has been widely used in dentistry because it is an effective caries prophylactic agent. However, excess fluoride may represent a hazard to human health, especially by causing injury on the genetic apparatus. Genotoxicity tests form an important part of cancer research and risk assessment of potential carcinogens. In the current study, the potential DNA damage associated with exposure to fluoride was assessed by the single cell gel (comet) assay in peripheral blood, oral mucosa and brain cells in vivo. Male Wistar rats were exposed to sodium fluoride (NaF) at a 0, 7 and 100 ppm dose for drinking water during 6 weeks. The results pointed out that NaF did not contribute to the DNA damage in all cellular types evaluated as depicted by the mean tail moment and tail intensity. These findings are clinically important since they represent an important contribution to the correct evaluation of the potential health risk associated with dental agents exposure.


Assuntos
Dano ao DNA , Fluoreto de Sódio/toxicidade , Análise de Variância , Animais , Encéfalo/efeitos dos fármacos , Ensaio Cometa , Feminino , Leucócitos/efeitos dos fármacos , Masculino , Mucosa Bucal/efeitos dos fármacos , Ratos , Ratos Wistar , Estatísticas não Paramétricas , Abastecimento de Água/análise
20.
Braz. j. med. biol. res ; 30(10): 1181-6, Oct. 1997. ilus
Artigo em Inglês | LILACS | ID: lil-201535

RESUMO

We placed spheres of synthetic hydroxyapatite (calcium chloride combined with sodium phosphate) in the eviscerated or enucleated orbital cavity of rats in order to evaluate the biocompatibility of this material with the orbital cavity. The study was conducted on 50 albino rats, 25 of which were submitted to enucleation and 25 to evisceration of one eye. The animals were sacrificed 7, 15, 21, 30 and 60 days after surgery and the orbital content was submitted to histopathological examination. A reaction of the young granulation tissue type was observed first. The hydroxyapatite was gradually surrounded by a granulomatous macrophage inflammatory response and covered with dense connective tissue that formed a sort of "mesh" septating and supporting progressively smaller blocks of the substance. The same type of reaction was observed in the enucleated and eviscerated cavities. We conclude that synthetic hydroxyapatite is an inert nonallergenic material which is appropriate for volume replacement in the anophthalmic cavity.


Assuntos
Ratos , Animais , Anoftalmia/terapia , Materiais Biocompatíveis , Modelos Animais de Doenças , Durapatita , Ratos Endogâmicos
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