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1.
J Clin Virol ; 63: 46-50, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25600604

RESUMO

We present a 17-year old girl with DOCK-8 deficiency, severe untreated oral HSV-1 infection and associated aggressive periodontitis. DOCK-8 deficiency is a primary immunodeficiency, caused by biallelicloss-of-function mutations in the DOCK8 gene, often leading to severe viral and fungal mucocutaneous infections. Nevertheless, to date DOCK8 has not been associated with severe periodontitis and inflammatory bone loss around teeth. Understanding whether DOCK8 deficiency or severe HSV-1 infection underlies susceptibility to periodontitis is central to this case and may provide insights into susceptibility factors for periodontitis in the general population. Our clinical and microbiological data suggest that severe HSV-1 infection is the driver of periodontal inflammation in this case.


Assuntos
Periodontite Agressiva/patologia , Periodontite Agressiva/virologia , Fatores de Troca do Nucleotídeo Guanina/deficiência , Herpes Simples/complicações , Herpes Simples/diagnóstico , Herpesvirus Humano 1/isolamento & purificação , Adolescente , Suscetibilidade a Doenças , Feminino , Herpes Simples/patologia , Humanos
2.
Langmuir ; 24(16): 8583-91, 2008 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-18646726

RESUMO

We have investigated bottom-up chemical synthesis of quaternary ammonium (QA) groups exhibiting antibacterial properties on stainless steel (SS) and filter paper surfaces via nonequilibrium, low-pressure plasma-enhanced functionalization. Ethylenediamine (ED) plasma under suitable conditions generated films rich in secondary and tertiary amines. These functional structures were covalently attached to the SS surface by treating SS with O 2 and hexamethyldisiloxane plasma prior to ED plasma treatment. QA structures were formed by reaction of the plasma-deposited amines with hexyl bromide and subsequently with methyl iodide. Structural compositions were examined by electron spectroscopy for chemical analysis and Fourier transform infrared spectroscopy, and surface topography was investigated with atomic force microscopy and water contact angle measurements. Modified SS surfaces exhibited greater than a 99.9% decrease in Staphylococcus aureus counts and 98% in the case of Klebsiella pneumoniae. The porous filter paper surfaces with immobilized QA groups inactivated 98.7% and 96.8% of S. aureus and K. pneumoniae, respectively. This technique will open up a novel way for the synthesis of stable and very efficient bactericidal surfaces with potential applications in development of advanced medical devices and implants with antimicrobial surfaces.


Assuntos
Antibacterianos/síntese química , Celulose/química , Klebsiella pneumoniae/efeitos dos fármacos , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/farmacologia , Aço Inoxidável/química , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Filtração , Microscopia de Força Atômica , Compostos de Amônio Quaternário/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Água/química
3.
J Biomater Sci Polym Ed ; 12(9): 1027-49, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11787520

RESUMO

Polyethylene and glass surfaces were functionalized under dichlorosilane-RF-cold-plasma environments and were employed as substrates for further in situ derivatization reactions and immobilization of papain. Surface functionality changes of RF-plasma-exposed surfaces were monitored under 40 kHz continuous discharge environments. The nature and morphology of derivatized substrates and the substrates bearing the immobilized enzyme were analyzed using survey and high resolution ESCA, ATR-FTIR, and fluorescence of chemical derivatization techniques. Spacer molecules intercalated between the substrates and the enzyme significantly increased the enzyme activity (comparable with the that of the free enzyme). Computer-aided conformational modeling of the substrate-spacer systems corroborated with experimental data indicated that an optimal distance might exist between the enzyme and the substrate. The activity of free and immobilized papain was monitored using benzoyl arginine ethyl ester assay. The pH data were recorded every 0.3 s over 25 min. The Michaelis-Menten kinetic constants were evaluated for immobilized enzymes. It was shown, that the immobilized papain retains most of its activity after several washing/assay cycles.


Assuntos
Arginina/análogos & derivados , Sangue , Enzimas Imobilizadas/química , Papaína/química , Polietileno/química , Arginina/metabolismo , Físico-Química/métodos , Enzimas Imobilizadas/metabolismo , Vidro , Humanos , Modelos Moleculares , Papaína/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade , Propriedades de Superfície
4.
Quintessence Int ; 31(2): 95-112, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11203919

RESUMO

Etiology and Epidemiology: The Greek term aphthai was initially used in relation to disorders of the mouth and is credited to Hippocrates (460-370 BC). Today, recurrent aphthous ulceration, or recurrent aphthous stomatitis (RAS), is recognized as the most common oral mucosal disease known to human beings. Considerable research attention has been devoted to elucidating the causes of RAS; local and systemic conditions, and genetic, immunologic, and infectious microbial factors all have been identified as potential etiopathogenic agents (Table 1). However, to date, no principal etiology has been discovered. Epidemiologic studies indicate that the prevalence of RAS is between 2% and 50% in the general population; most estimates fall between 5% and 25%. In selected groups, such as medical and dental students, it has been observed with a frequency as high as 50% to 60%. The peak age of onset for RAS is between 10 and 19 years. After childhood and adolescence, it may continue throughout the entire human lifespan without geographic or age-, sex-, or race-related preference.


Assuntos
Estomatite Aftosa , Administração Tópica , Anti-Inflamatórios/uso terapêutico , Glucocorticoides , Humanos , Imunossupressores/uso terapêutico , Prevalência , Encaminhamento e Consulta , Estomatite Aftosa/diagnóstico , Estomatite Aftosa/epidemiologia , Estomatite Aftosa/etiologia , Estomatite Aftosa/terapia , Talidomida/uso terapêutico
5.
J Biomater Sci Polym Ed ; 9(4): 389-404, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9586786

RESUMO

In this contribution the immobilization of alpha-chymotrypsin on plasma activated PET and PP surfaces is investigated. The 'anchoring' C=O groups on polymer surfaces were created under RF-O2-plasma environments. The identity and relative concentrations of plasma-created functionalities were evaluated using survey and high resolution X-ray photoelectron spectroscopy, and differential attenuated total reflectance-FTIR spectroscopy. Surface morphology changes of plasma-exposed substrates were analyzed by atomic force microscopy. Enzyme assays were performed from both virgin and plasma modified samples which underwent the immobilization procedure. It was demonstrated that cold-plasma technique is suitable for generating functional, synthetic polymeric surfaces which can initiate enzyme coupling reactions. It also has been shown that the activity of the immobilized enzyme is lower in comparison to the free enzyme. Reduced conformational mobility resulting from multiple-point coupling process might be responsible for this behavior.


Assuntos
Argônio , Quimotripsina/química , Enzimas Imobilizadas/química , Oxigênio , Polietilenotereftalatos/química , Polipropilenos/química , Quimotripsina/metabolismo , Ativação Enzimática , Enzimas Imobilizadas/metabolismo , Microscopia de Força Atômica , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
6.
J Biol Chem ; 272(47): 29801-9, 1997 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-9368052

RESUMO

The promoter regions of both the interferon regulatory factor (IRF1) and p53 antioncogenes contain a previously unidentified sequence denoted IRF1 p53 common sequence (IPCS), which markedly increases the transcriptional activity of a reporter gene placed under the control of an heterologous promoter in transfected U937 cells. In contrast, transfection of U937 cells with reporter vectors containing p53 and IRF1 promoters with mutated IPCS sites resulted in a 4-fold reduction in the constitutive expression of those two genes. The transcriptional activity of IPCS is strictly correlated with the binding of a novel nuclear factor, IPCS-binding factor (IPCS-BF). IPCS-BF, which is composed of a single polypeptide of 26 kDa, is present constitutively in nuclear extracts of both U937 cells and peripheral blood mononuclear cells from healthy donors. The finding that the pattern of binding of IPCS-BF to the IPCS is unlike that of any known transcription factor and that the IPCS sequence does not exhibit any significant homology with any known binding site present in the data base, strongly suggest that IPCS-BF is a novel transcription factor which, by virtue of this ability to regulate the expression of the p53 and IRF1 genes, could play a central role in the control of cell proliferation and/or apoptosis.


Assuntos
Proteínas de Ligação a DNA/genética , Genes Reguladores , Interferon gama/genética , Fosfoproteínas/genética , Fatores de Transcrição/genética , Transcrição Gênica , Proteína Supressora de Tumor p53/genética , Humanos , Fator Regulador 1 de Interferon , Mutagênese Sítio-Dirigida , Análise de Sequência de DNA , Transfecção , Células Tumorais Cultivadas
7.
J Oral Maxillofac Surg ; 55(5): 470-7; discussion 477-8, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9146516

RESUMO

PURPOSE: This study reviews the accuracy of preopertive diagnosis of mandibular invasion by oral squamous cell carcinoma and assesses the role of marginal resection of the mandible in its treatment. PATIENTS AND METHODS: A retrospective study of a 5-year cohort of 46 patients who underwent mandibular resection for previously untreated oral squamous cell carcinoma was done. Data evaluated included age; sex; site and stage of cancer; preoperative clinical, panoramic, and computed tomography (CT) evaluations; and histologic findings on the resection specimen. The type of mandibular resection (segmental vs marginal) and treatment outcome also were compared. RESULTS: Clinical examination, panoramic radiographs, and CT scans were 78.5% to 82.6% accurate in diagnosing mandibular invasion by squamous carcinoma. Clinical examination and panoramic radiographs are more sensitive than CT scans (86.6% vs 53%), but CT scans were more specific (92.5% vs 80%). The mandible was involved in 65% of patients with segmental resection and 7.6% of patients who had a marginal resection. Nineteen percent of the patients in the marginal resection group died of their oral cancer, two of five patients with local recurrence. Ten percent of patients in the segmental resection group died of oral cancer; no local recurrences were seen. CONCLUSION: There is no completely accurate method of diagnosing bony invasion of the mandible by oral squamous cell carcinoma. A combination of clinical examination, plain radiographs, and computed tomography (CT) scans may improve the diagnosis. Marginal resection is best reserved for cancers close to the bone with no invasion, minimal cortical invasion, or with early "arrosive" invasion. It is best in the symphysis region. Careful case selection will allow a favorable oncologic outcome with preservation of the mandibular contour.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/cirurgia , Mandíbula/cirurgia , Neoplasias Mandibulares/diagnóstico , Neoplasias Mandibulares/cirurgia , Invasividade Neoplásica/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Panorâmica , Estudos Retrospectivos , Sensibilidade e Especificidade , Cirurgia Bucal/métodos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
8.
Biochem Pharmacol ; 52(11): 1719-27, 1996 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-8986134

RESUMO

Prolactin induces milk protein gene expression in rabbit primary mammary cells without any concomitant cell multiplication. Prolactin or other lactogenic hormones is the major inducer of cell division in the rat lymphoid Nb2 cells. In Nb2 cells, prolactin also rapidly induces the expression of the c-myc gene, and beta-actin and stathmin gene expression is induced more slowly. The possible involvement of casein kinase II (CKII), mitogen-activated protein kinase (MAPK) and protein kinase C (PKC) in these process is not well known. The present work was undertaken to evaluate the effect of prolactin on these protein kinases and to determine the possible involvement of these enzymes in the activity of several genes under the control of the hormone. In rabbit mammary cells, prolactin did not alter CKII activity but did transiently stimulate MAP kinase activity. Prolactin also stimulated Ca(2+)-independent PKC. This effect was visible after 10 min and was maintained for at least 24 hr. Staurosporine, an inhibitor of PKC and of several tyrosine kinases altered Ca(2+)-independent PKC only moderately. In contrast, GF 109203X, a potent and specific inhibitor of PKC, abrogated almost all PKC activity. Staurosporine, but not GF 109203X, prevented the induction of the casein gene by prolactin. In Nb2 cells, prolactin induced a slow stimulation of CKII activity. The hormone did not induce MAP kinase activity. Prolactin stimulated Ca(2+)-independent PKC over periods of 24 hr. GF 109203X, but not staurosporine, inhibited PKC activity, whereas staurosporine but not GF 109203X, inhibited the induction of Nb2 cell multiplication and the accumulation of c-myc, beta-actin and stathmin mRNAs. From these data, it can be concluded that (1) the stimulation of CKII by prolactin in Nb2 cells is concomitant with cell multiplication: (2) MAPK stimulation is not necessary for prolactin to induce Nb2 cell multiplication; and (3) PKC is stimulated in mammary and Nb2 cells, but this stimulation is not required for prolactin to stimulate casein, c-myc, beta-actin and stathmin gene expression and Nb2 cell division.


Assuntos
Proteínas Quinases Dependentes de Cálcio-Calmodulina/efeitos dos fármacos , Linfócitos/enzimologia , Glândulas Mamárias Animais/enzimologia , Prolactina/farmacologia , Proteína Quinase C/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Animais , Caseína Quinase II , Células Cultivadas , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Proteína Quinase C/antagonistas & inibidores , Coelhos , Ratos , Estaurosporina/farmacologia
9.
Int J Biochem Cell Biol ; 27(7): 707-18, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7648427

RESUMO

In all species, milk protein genes are specifically expressed in the mammary gland under the control of lactogenic hormones and extracellular matrix. In rabbit, casein gene expression is induced by prolactin alone and this induction is amplified by extracellular matrix. Transferrin gene expression is induced by extracellular matrix in the absence of hormones. The transduction mechanisms of prolactin and extracellular matrix to milk protein genes is only partly known. The present study has been undertaken to determine if protein kinases and phosphatases are involved in these mechanisms. Rabbit primary mammary cells were cultured in three different conditions (i) directly on floating collagen I, (ii) on plastic after a trypsinization to remove endogenous extracellular matrix, and (iii) on floating collagen I after a trypsinization to restore a functional extracellular matrix. In these culture conditions, prolactin and several protein kinase and phosphatase inhibitors were added to the medium. The expression of alpha S1-casein and transferrin genes was evaluated using Northern blotting analysis. In cells cultured directly on collagen I, staurosporine, quercetin and 6-dimethylaminopurine strongly inhibited prolactin action of alpha S1-casein gene whereas herbimycin A was only partly inhibitory. An erbstatin analogue, tyrosine phosphate, 1(5 isoquinolylsulphonyl) 2-methylpiperazine and GF 109 203 X did not alter prolactin action. The inhibitors which inhibited prolactin action when cells were directly cultured on collagen I were also those which prevented the induction of alpha S1-casein gene expression when cells were cultured on plastic in the absence of extracellular matrix. The induction of transferrin gene by the extracellular matrix was inhibited slightly by quercetin. Okadaic acid, phenylarsine oxide and sodium pervanadate which inhibit Ser/Thr and Tyr phosphatase inhibitors were unable to mimic prolactin action on alpha S1-casein gene expression. On the contrary, these inhibitors prevented prolactin action. These data suggest that a cascade including protein kinases and phosphatases for Ser/Thr and Tyr phosphate is involved in the transduction of the prolactin message from its receptor to casein genes. The signal delivered to the mammary cells by the extracellular matrix is quite different, possibly involving another cascade of protein kinases.


Assuntos
Caseínas/genética , Matriz Extracelular/fisiologia , Glândulas Mamárias Animais/metabolismo , Fosfoproteínas Fosfatases/antagonistas & inibidores , Prolactina/farmacologia , Inibidores de Proteínas Quinases , Transferrina/genética , Animais , Sequência de Bases , Células Cultivadas , Colágeno , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Dados de Sequência Molecular , Fosfoproteínas Fosfatases/metabolismo , Proteínas Quinases/metabolismo , Proteínas Tirosina Quinases/antagonistas & inibidores , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Coelhos
10.
Eur J Endocrinol ; 130(5): 522-9, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8180682

RESUMO

The concentration of transferrin mRNA was evaluated during pregnancy and lactation in rabbit mammary gland and liver using northern blot and dot blot assays. Transferrin mRNA was present in the virgin rabbit mammary gland and its concentration increased as pregnancy proceeded, with a major enhancement after day 15. A high concentration was reached 3 days after parturition, with no additional increase during lactation and with a marked decline after weaning. During the same period, the concentration of transferrin mRNA showed only a very weak variation in liver. This mRNA was six times more abundant in mammary gland than in liver of lactating rabbit. The accumulation of transferrin mRNA in the mammary gland was concomitant with the accumulation of alpha s1-, beta-, kappa-casein and WAP (whey acidic protein) mRNAs. The concentration of glyceraldehyde 3-phosphate dehydrogenase mRNA, taken as a non-inducible control mRNA, declined progressively during pregnancy to reach its lower level in lactation. These observations suggest that casein, WAP and transferrin mRNAs are subjected to a similar control mechanism in vivo, at least in the second half of pregnancy and during lactation. Experiments carried out in vitro using isolated rabbit epithelial mammary cells cultured on collagen I gel indicated that transferrin mRNA was abundant and only weakly inducible by the lactogenic hormones insulin, cortisol and prolactin, as opposed to caseins and WAP mRNAs. R5020, an analogue of progesterone, inhibited at most very slightly the accumulation of alpha s1-casein mRNA in the presence of prolactin and it did not reduce the expression of transferrin gene.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Lactação/metabolismo , Glândulas Mamárias Animais/metabolismo , Prenhez/metabolismo , Coelhos/metabolismo , Transferrina/genética , Animais , Sequência de Bases , Northern Blotting , Caseínas/biossíntese , Caseínas/genética , Células Cultivadas , Primers do DNA/química , Matriz Extracelular/fisiologia , Feminino , Regulação da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenases/biossíntese , Gliceraldeído-3-Fosfato Desidrogenases/genética , Fígado/química , Fígado/metabolismo , Glândulas Mamárias Animais/química , Glândulas Mamárias Animais/citologia , Proteínas do Leite/biossíntese , Proteínas do Leite/genética , Dados de Sequência Molecular , Fragmentos de Peptídeos/biossíntese , Fragmentos de Peptídeos/genética , Reação em Cadeia da Polimerase , Gravidez , RNA Mensageiro/análise , Transferrina/biossíntese , Transferrina/metabolismo , Desmame
11.
Mol Cell Endocrinol ; 92(1): 127-34, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8472863

RESUMO

Prolactin has many known functions and one of them is to induce the expression of milk protein gene expression in the mammary gland. Specific membrane receptors have been recently characterized but the transduction mechanism involved in the transfer of the prolactin signal to milk protein genes remains unknown. In the present work, it is shown that several protein kinase inhibitors block prolactin action on milk protein genes. Primary rabbit mammary cells were cultured for several days on floating collagen gel in a serum-free medium. Prolactin and the inhibitors of protein kinase were then added to the culture medium. After 1 day, the concentration of alpha s1-casein in the culture medium was measured using a specific radioimmunoassay. The concentration of several mRNAs in cell extracts was also evaluated using Northern blot analysis. alpha s1-Casein secretion and alpha s1-casein mRNA accumulation were induced by prolactin. This induction was blocked by staurosporine, sphingosine, quercetin, genistein and to some extent by o-hydroxyphenyl acetate, but not by H7, polymyxin B, benzylsuccinate and lavendustin A. The concentration of the mRNA coding for transferrin, which is abundantly secreted in rabbit milk independently of prolactin action, was only moderately altered by the inhibitors. The concentration of two house-keeping mRNAs, beta-actin and glyceraldehyde 3-phosphate dehydrogenase, was lowered only by genistein after 1 day but not after 4 h of culture. These data show for the first time that a Ser/Thre kinase, which is not kinase C, and possibly a tyrosine kinase is involved in the transduction of the prolactin message from the receptor to the milk protein genes.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Proteínas do Leite/biossíntese , Prolactina/farmacologia , Inibidores de Proteínas Quinases , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina , Adenina/análogos & derivados , Adenina/farmacologia , Alcaloides/farmacologia , Animais , Células Cultivadas , Células Epiteliais , Epitélio/efeitos dos fármacos , Feminino , Genisteína , Isoflavonas/farmacologia , Isoquinolinas/farmacologia , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Proteínas do Leite/genética , Fenóis/farmacologia , Fenilacetatos/farmacologia , Piperazinas/farmacologia , Polimixina B/farmacologia , Gravidez , Quercetina/farmacologia , Coelhos , Esfingosina/farmacologia , Estaurosporina , Succinatos/farmacologia
12.
Biosci Rep ; 12(3): 189-97, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1391684

RESUMO

Two protein kinase-inhibitors, 6-dimethyl amino purine and 2-amino purine inhibited induction of beta-casein synthesis by prolactin when added to the culture medium of rabbit mammary explant and cells. The accumulation of the mRNA for alpha s1- and beta-caseins and for whey acidic protein did not take place in the presence of the inhibitors whereas beta-actin mRNA concentration was not altered. In the same experimental conditions, H7, an inhibitor of protein kinase C and, to a lower extent, of protein kinase A did not prevent prolactin from acting. These data suggest for the first time that specific protein kinases are involved in the transduction of the prolactin signal to milk protein genes.


Assuntos
2-Aminopurina/farmacologia , Adenina/análogos & derivados , Proteínas do Leite/genética , Adenina/farmacologia , Animais , Caseínas/genética , Células Cultivadas , Feminino , Expressão Gênica/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/metabolismo , Prolactina/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coelhos
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