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1.
J Microbiol Methods ; 169: 105818, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31881287

RESUMO

Clostridium tyrobutyricum is the major agent that causes the blowing defect in cheese due to the germination of its dormant spores during the ripening stage. As a result, many of the affected cheeses show cavities and cracks, which cause the product loss in most cases. Nowadays, there is not a fast method capable of detecting milk contaminated with C. tyrobutyricum spores. The aim of this study has been to develop a fast and reliable method based on real time PCR (qPCR) to detect C. tyrobutyricum spores in raw milk. One of the main limitations has been to find a good procedure for the spore disruption to extract the DNA due to its high resistance. For this reason, different disruption methods have been tested, including chemical agents, bead beating, enzymatic and microwave treatment. Furthermore, an enzymatic treatment with subtilisin was applied for milk clarification and recovery of spores. The comparison of the assayed methods has been made using sterile milk spiked with C. tyrobutyricum spores, obtained in solid or liquid medium. The results showed that microwave treatment followed by a standard DNA purification step was found to be the best disruption method. The Ct values obtained for spores were higher than those found for vegetative cells by qPCR, for the same quantity of DNA. This difference could be due to the action of the Small Acid Soluble Proteins (SASP) in the DNA packaging of spores. Moreover, spores obtained in agar plate were found more resistant to disruption than those obtained in liquid medium. Subtilisin and microwave treatments were found to be successful for DNA extraction from C. tyrobutyricum spores in milk and subsequent identification by qPCR. However, the differences observed between the amplification of DNA from spores obtained in different media and from vegetative cells have to be taken into account to optimize a method for C. tyrobutyricum detection.


Assuntos
Queijo/microbiologia , Clostridium tyrobutyricum/genética , DNA Bacteriano/genética , Leite/microbiologia , Esporos Bacterianos/genética , Animais , Extratos Celulares/genética , Clostridium tyrobutyricum/isolamento & purificação , Microbiologia de Alimentos/métodos , Reação em Cadeia da Polimerase em Tempo Real , Esporos Bacterianos/metabolismo , Subtilisina/farmacologia
4.
Int J Oral Maxillofac Surg ; 47(8): 1079-1085, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29735198

RESUMO

The aim of this retrospective clinical study was to evaluate the short-term implant success rate and marginal bone loss in full-arch fixed prosthetic maxillary rehabilitations supported by implants in immediate function with the All-on-4 treatment concept placed with insertion torque of <30N·cm or ≥30N·cm. This study included 83 patients (69 female, 14 male) with 332 implants placed (120 inserted with <30N·cm and 212 inserted with ≥30N·cm) who were treated between January 2010 and March 2013. Outcome measures were implant success and marginal bone loss at 1year of follow-up. Ten patients (12.0%; 13 implants inserted with <30N·cm and 27 implants with ≥30N·cm) were lost to follow-up. The cumulative implant success rate was 97.5% at the patient level, and 98.3% for implants inserted with <30N·cm and 97.5% for implants inserted with ≥30N·cm. The mean±standard deviation marginal bone loss at 1year was 1.14±0.38mm for implants inserted with <30N·cm and 1.39±0.49mm for implants inserted with ≥30N·cm (significant difference; P<0.001, Wilcoxon signed rank test). These results indicate that implants with insertion torques of <30N·cm may render comparable success rates and marginal bone loss at 1year compared to implants inserted with insertion torques of ≥30N·cm.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Prótese Dentária Fixada por Implante , Prótese Total Superior , Arcada Edêntula/reabilitação , Maxila/cirurgia , Perda do Osso Alveolar/epidemiologia , Falha de Restauração Dentária/estatística & dados numéricos , Planejamento de Dentadura , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Torque , Resultado do Tratamento
5.
Int J Oral Maxillofac Surg ; 46(12): 1592-1599, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28655434

RESUMO

The aim of this study was to evaluate the outcomes of immediate full-arch prostheses supported by zygomatic implants alone or in combination with standard fixtures after a minimum of 6 years of loading. From October 2008 to April 2010, 15 patients with severely atrophic maxillae were treated using four zygomatic implants or two zygomatic implants in conjunction with two conventional fixtures. All subjects received a fixed screw-retained prosthesis within 3hours of surgery, while the final restoration was delivered after 6 months. Follow-up examinations were scheduled to evaluate zygomatic implant survival, conventional dental implant success, prosthetic success, plaque and bleeding scores, marginal bone loss for conventional dental implants, and patient satisfaction. Forty-two zygomatic fixtures and 18 standard implants were placed. Patients were followed up for a minimum of 79 months (range 79-97 months, average 90.61 months). No implant was lost, leading to implant and prosthetic survival rates of 100%. Bone loss for conventional implants averaged 1.39±0.10mm after 6 years of function, leading to a 100% implant success rate. High levels of patient satisfaction were recorded. These medium-term results indicate that immediate full-arch rehabilitation supported by zygomatic implants could be considered a viable treatment modality for the severely atrophic maxilla.


Assuntos
Implantes Dentários , Prótese Dentária Fixada por Implante , Carga Imediata em Implante Dentário , Arcada Edêntula/reabilitação , Maxila/patologia , Maxila/cirurgia , Zigoma/cirurgia , Idoso , Atrofia , Feminino , Seguimentos , Humanos , Arcada Edêntula/diagnóstico por imagem , Masculino , Maxila/diagnóstico por imagem , Pessoa de Meia-Idade , Estudos Prospectivos , Radiografia Panorâmica , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Zigoma/diagnóstico por imagem
6.
J Oral Rehabil ; 43(11): 863-870, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27611605

RESUMO

More studies evaluating the outcome of dental implant restorations in diabetics are needed. To investigate the outcome of immediate function implant rehabilitations in diabetic patients. This retrospective cohort study included 70 diabetic patients (type 1 = six patients; type 2 = 64 patients; 33 females and 37 males, mean age=59 years), rehabilitated with 352 implants. Primary outcome measure was implant survival estimated at 5 years through the Kaplan-Meier product limit estimator using the patient as unit of analysis (first implant failure as reference); secondary outcome measures were marginal bone loss and biological complications. Risk indicators associated with bone loss >2·0 mm were tested in a multivariate logistic regression model. The level of significance considered was 5%. Seven patients were lost to follow-up (10%). Seven patients lost ten implants rendering a global implant cumulative survival rate for diabetic patients of 89·8% (type 1 = 80·0%; type 2 = 90·5%). The average (95% confidence interval) marginal bone loss at 1 and 5 years was 1·64 mm (0·00;3·32) and 2·55 mm (1·38;3·72) for type 1 diabetic patients, 0·79 mm (0·59;1·00) and 1·45 mm (1·09;1·82) for type 2 diabetic patients and 0·88 mm (0·65;1·10) and 1·56 mm (1·21;1·91) overall. Biological complications occurred in seven patients. Female gender (OR = 28·1) and smoking habits (OR = 10·3) were risk indicators for marginal bone loss >2·0 mm at 5 years when controlled for other variables of interest. Implant rehabilitations represent a valid treatment for diabetic patients, with a good risk/benefit ratio. Female gender and smoking habits were risk indicators for a higher marginal bone resorption at 5 years.


Assuntos
Perda do Osso Alveolar/prevenção & controle , Implantes Dentários , Prótese Dentária Fixada por Implante , Complicações do Diabetes/prevenção & controle , Diabetes Mellitus/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda do Osso Alveolar/fisiopatologia , Glicemia , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , Fatores de Risco
7.
Clin. transl. oncol. (Print) ; 17(8): 547-667, ago. 2015. ilus
Artigo em Inglês | IBECS | ID: ibc-138181

RESUMO

Purpose. Human Apo2-Ligand/TRAIL secreted by natural killer cells and cytotoxic T lymphocytes plays an important role immunosurveillance controlling tumor growth and metastasis. Moreover, the fact that Apo2L/TRAIL is capable of inducing cell death in tumor cells but not in normal cells makes this death ligand a promising anti-tumor agent. Previous data from our group demonstrated that Apo2L/TRAIL was physiologically released as transmembrane protein inserted in lipid vesicles, called exosomes. Recently, we demonstrated that artificial lipid nanoparticles coated with bioactive Apo2L/TRAIL (LUV-TRAIL) resembling the natural exosomes, greatly improved Apo2L/TRAIL activity and were able to induce apoptosis in hematological malignancies. In this study, we have deepened in the underlying mechanism of action of LUV-TRAIL in hematologic cells. Methods/patients. Cytotoxic ability of LUV-TRAIL was assessed on Jurkat cells either over-expressing the anti-apoptotic protein Mcl1 or down-regulating the pro-apoptotic protein Bim previously generated in our laboratory. We also tested LUV-TRAIL cytotoxic ability against primary human leukemic cells from T-cell ALL patient. Results. Silencing Bim but not Mcl-1 over-expression partially protects Jurkat cells from apoptosis induced by sTRAIL. LUV-TRAIL induced caspase-8 and caspase-3 activation and killed Jurkat-Mcl1 and Jurkat-shBim more efficiently than sTRAIL independently of the mitochondrial pathway. On the other hand, LUV-TRAIL were clearly more cytotoxic against primary leukemic cells from a T-cell ALL patient than sTRAIL. Conclusion. Tethering Apo2L/TRAIL to the surface of lipid nanoparticles greatly increases its bioactivity and could be of potential use in anti-tumor therapeutics (AU)


No disponible


Assuntos
Feminino , Humanos , Masculino , Imunoterapia/métodos , Lipossomos , Receptores do Fator de Necrose Tumoral/análise , Testes Imunológicos de Citotoxicidade/métodos , Morte Celular , Imunoterapia , Apoptose , Forma do Núcleo Celular , Western Blotting/métodos , 28599
8.
Clin Transl Oncol ; 17(8): 657-67, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25967100

RESUMO

PURPOSE: Human Apo2-Ligand/TRAIL secreted by natural killer cells and cytotoxic T lymphocytes plays an important role immunosurveillance controlling tumor growth and metastasis. Moreover, the fact that Apo2L/TRAIL is capable of inducing cell death in tumor cells but not in normal cells makes this death ligand a promising anti-tumor agent. Previous data from our group demonstrated that Apo2L/TRAIL was physiologically released as transmembrane protein inserted in lipid vesicles, called exosomes. Recently, we demonstrated that artificial lipid nanoparticles coated with bioactive Apo2L/TRAIL (LUV-TRAIL) resembling the natural exosomes, greatly improved Apo2L/TRAIL activity and were able to induce apoptosis in hematological malignancies. In this study, we have deepened in the underlying mechanism of action of LUV-TRAIL in hematologic cells. METHODS/PATIENTS: Cytotoxic ability of LUV-TRAIL was assessed on Jurkat cells either over-expressing the anti-apoptotic protein Mcl1 or down-regulating the pro-apoptotic protein Bim previously generated in our laboratory. We also tested LUV-TRAIL cytotoxic ability against primary human leukemic cells from T-cell ALL patient. RESULTS: Silencing Bim but not Mcl-1 over-expression partially protects Jurkat cells from apoptosis induced by sTRAIL. LUV-TRAIL induced caspase-8 and caspase-3 activation and killed Jurkat-Mcl1 and Jurkat-shBim more efficiently than sTRAIL independently of the mitochondrial pathway. On the other hand, LUV-TRAIL were clearly more cytotoxic against primary leukemic cells from a T-cell ALL patient than sTRAIL. CONCLUSION: Tethering Apo2L/TRAIL to the surface of lipid nanoparticles greatly increases its bioactivity and could be of potential use in anti-tumor therapeutics.


Assuntos
Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Apoptose , Imunoterapia , Leucemia/patologia , Leucemia/terapia , Lipossomos , Proteínas de Membrana/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Western Blotting , Proliferação de Células , Células Cultivadas , Regulação para Baixo , Humanos , Técnicas Imunoenzimáticas , Leucemia/imunologia , Leucemia/metabolismo , Linfócitos/citologia , Linfócitos/imunologia , Linfócitos/metabolismo , Proteínas de Membrana/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transdução de Sinais
9.
J Oral Rehabil ; 42(8): 615-23, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25757870

RESUMO

More studies evaluating the outcome of short-length dental implants in immediate loading are needed. To evaluate the use of short-length tapered implants in immediate loading for complete edentulous maxillae rehabilitations using an All-on-4 design. This retrospective clinical study included a cohort of 43 patients with 172 implants (74 short-length implants) inserted in low bone quantity. The patients were followed between 4 months and 6 years (average = 3 years). Outcome measures were implant survival, marginal bone remodelling, biological and mechanical complications. Two patients with four short-length implants were lost to follow-up during the first year. Three short and three long implants failed in four patients, rendering an overall cumulative survival rate implant and patient level, respectively, of 95.7% and 95.1% for short implants, 100% for regular implants and 96.6% and 95.2% for long implants. The average marginal bone remodelling at 1 and 3 years was 0.97 and 1.25 mm for the short implants, 0.82 and 0.87 mm for regular implants and 0.87 and 0.98 mm for long implants. Three patients presented 4 short-length implants with peri-implant pockets (3 implants in 2 patients were pseudo-pockets). Mechanical complications were registered in 13 patients (7 provisional prostheses fractures and 6 abutment screw loosening). All complications were treated successfully. Within the limitations of this clinical study, the short-term outcome of fixed prosthetic complete edentulous maxillae rehabilitations supported by short-length implants inserted in low bone quantity areas is viable. Long-term clinical studies are necessary for evaluating the outcome of these implants.


Assuntos
Implantes Dentários , Planejamento de Prótese Dentária , Prótese Dentária Fixada por Implante , Carga Imediata em Implante Dentário , Arcada Edêntula/reabilitação , Adulto , Idoso , Idoso de 80 Anos ou mais , Falha de Restauração Dentária , Feminino , Humanos , Masculino , Maxila/fisiopatologia , Maxila/cirurgia , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
10.
Clin. transl. oncol. (Print) ; 17(2): 121-132, feb. 2015. ilus
Artigo em Inglês | IBECS | ID: ibc-132882

RESUMO

Purpose. Sorafenib is a multikinase inhibitor that targets the MAPK pathway and is currently used for the treatment of hepatocellular and renal carcinoma. Recently, it has been shown that sorafenib is also cytotoxic to multiple myeloma (MM) cells. Here, we have further analyzed the mechanism of sorafenib-induced death in MM cells. Methods. Cell death induced by sorafenib in MM cell lines and in plasma cells from MM patients was evaluated by analysis of gene expression by RT-MLPA and quantitative PCR, protein levels and functionality by Western blot and flow cytometry and gene silencing with siRNA. Results. Cell death was characterized by phosphatidylserine exposure, ΔΨm loss, cytochrome c release and caspase activation, hallmarks of apoptosis. DL50 at 24 h ranged from 6 to 10 µM. Ex vivo treatment with 20 µM sorafenib induced apoptosis in around 80 % myeloma cells from six multiple myeloma patients. Sorafenib induced caspase-dependent degradation of Bcl-xL and Mcl-1 proteins, destabilizing the mitochondria and speeding up the development of apoptosis. Sorafenib treatment increased levels of Puma at mRNA and protein level and gene silencing with siRNA confirmed a relevant role for Puma in the induction of apoptosis. Co-treatment with the pan-caspase inhibitor Z-VAD-fmk prevented cell death to a variable degree depending on the cell line. In RPMI 8226 cells, Z-VAD-fmk prevented most of sorafenib-induced death. However, death in MM.1S was only prevented by co-incubation with both Z-VAD-fmk and the RIP1K inhibitor necrostatin-1, indicating that under conditions of inefficient caspase activation, sorafenib induces death by necroptosis. Conclusion. Our results demonstrate a key role for Puma in the triggering of sorafenib-induced apoptosis and that this drug can also induce death by necroptosis in multiple myeloma cells (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Mieloma Múltiplo/induzido quimicamente , Mieloma Múltiplo/patologia , Antineoplásicos/efeitos adversos , Apoptose , Proteína de Suscetibilidade a Apoptose Celular/análise , Morte Celular , Necrose/induzido quimicamente , Mieloma Múltiplo/complicações , Mieloma Múltiplo/secundário , Antineoplásicos/toxicidade , Citometria de Fluxo/métodos , Expressão Gênica , Proteína de Sequência 1 de Leucemia de Células Mieloides , Proteína de Sequência 1 de Leucemia de Células Mieloides/toxicidade , Proteína bcl-X/análise , Proteína bcl-X/toxicidade
11.
Clin Transl Oncol ; 17(2): 121-32, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25037851

RESUMO

PURPOSE: Sorafenib is a multikinase inhibitor that targets the MAPK pathway and is currently used for the treatment of hepatocellular and renal carcinoma. Recently, it has been shown that sorafenib is also cytotoxic to multiple myeloma (MM) cells. Here, we have further analyzed the mechanism of sorafenib-induced death in MM cells. METHODS: Cell death induced by sorafenib in MM cell lines and in plasma cells from MM patients was evaluated by analysis of gene expression by RT-MLPA and quantitative PCR, protein levels and functionality by Western blot and flow cytometry and gene silencing with siRNA. RESULTS: Cell death was characterized by phosphatidylserine exposure, ΔΨm loss, cytochrome c release and caspase activation, hallmarks of apoptosis. DL50 at 24 h ranged from 6 to 10 µM. Ex vivo treatment with 20 µM sorafenib induced apoptosis in around 80 % myeloma cells from six multiple myeloma patients. Sorafenib induced caspase-dependent degradation of Bcl-xL and Mcl-1 proteins, destabilizing the mitochondria and speeding up the development of apoptosis. Sorafenib treatment increased levels of Puma at mRNA and protein level and gene silencing with siRNA confirmed a relevant role for Puma in the induction of apoptosis. Co-treatment with the pan-caspase inhibitor Z-VAD-fmk prevented cell death to a variable degree depending on the cell line. In RPMI 8226 cells, Z-VAD-fmk prevented most of sorafenib-induced death. However, death in MM.1S was only prevented by co-incubation with both Z-VAD-fmk and the RIP1K inhibitor necrostatin-1, indicating that under conditions of inefficient caspase activation, sorafenib induces death by necroptosis. CONCLUSION: Our results demonstrate a key role for Puma in the triggering of sorafenib-induced apoptosis and that this drug can also induce death by necroptosis in multiple myeloma cells.


Assuntos
Antineoplásicos/farmacologia , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose/efeitos dos fármacos , Mitocôndrias/patologia , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/patologia , Niacinamida/análogos & derivados , Compostos de Fenilureia/farmacologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Reguladoras de Apoptose/antagonistas & inibidores , Proteínas Reguladoras de Apoptose/genética , Western Blotting , Inibidores de Caspase/farmacologia , Caspases/química , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mieloma Múltiplo/metabolismo , Necrose , Niacinamida/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sorafenibe , Células Tumorais Cultivadas
12.
Eur J Prosthodont Restor Dent ; 22(3): 125-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25831714

RESUMO

Peri-implant pathology is a multifactorial disease, incorporating biological and biomechanical components in its pathogenesis; however; few studies address the possible risk factors. This study investigated the effect of implant location and position characteristics on the occurrence of Peri-implant pathology. A total of 1350 patients with dental implants were included 270 patients with peri-implant pathology and 1080 healthy controls. Results demonstrated that in the absence of bacterial plaque and smoking, the variable proximity of the implant to other implants or teeth revealed a significant difference between groups with a protective effect, but not in the presence of bacterial plaque and smoking.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Peri-Implantite/etiologia , Estomatite/etiologia , Adulto , Estudos de Casos e Controles , Placa Dentária/complicações , Prótese Dentária Fixada por Implante , Feminino , Seguimentos , Humanos , Arcada Parcialmente Edêntula/reabilitação , Arcada Parcialmente Edêntula/cirurgia , Masculino , Pessoa de Meia-Idade , Boca Edêntula/reabilitação , Boca Edêntula/cirurgia , Perda da Inserção Periodontal/etiologia , Índice Periodontal , Bolsa Periodontal/etiologia , Estudos Retrospectivos , Fatores de Risco , Fumar , Dente/patologia
13.
Cell Death Dis ; 3: e390, 2012 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-22972376

RESUMO

The alkylating DNA-damage agent N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) induces a form of caspase-independent necroptosis implicating the mitochondrial flavoprotein apoptosis-inducing factor (AIF). Following the activation of PARP-1 (poly(ADP-ribose) polymerase-1), calpains, BID (BH3 interacting domain death agonist), and BAX (Bcl-2-associated X protein), the apoptogenic form of AIF (tAIF) is translocated to the nucleus where, associated with Ser139-phosphorylated histone H2AX (γH2AX), it creates a DNA-degrading complex that provokes chromatinolysis and cell death by necroptosis. The generation of γH2AX is crucial for this form of cell death, as mutation of H2AX Ser139 to Ala or genetic ablation of H2AX abolish both chromatinolysis and necroptosis. On the contrary, reintroduction of H2AX-wt or the phosphomimetic H2AX mutant (H2AX-S139E) into H2AX(-/-) cells resensitizes to MNNG-triggered necroptosis. Employing a pharmacological approach and gene knockout cells, we also demonstrate in this paper that the phosphatidylinositol-3-OH kinase-related kinases (PIKKs) ATM (ataxia telangiectasia mutated) and DNA-dependent protein kinase (DNA-PK) mediate γH2AX generation and, consequently, MNNG-induced necroptosis. By contrast, H2AX phosphorylation is not regulated by ATR or other H2AX-related kinases, such as JNK. Interestingly, ATM and DNA-PK phosphorylate H2AX at Ser139 in a synergistic manner with different kinetics of activation. Early after MNNG treatment, ATM generates γH2AX. Further, DNA-PK contributes to H2AX Ser139 phosphorylation. In revealing the pivotal role of PIKKs in MNNG-induced cell death, our data uncover a milestone in the mechanisms regulating AIF-mediated caspase-independent necroptosis.


Assuntos
Fator de Indução de Apoptose/metabolismo , Caspases/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteína Quinase Ativada por DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Histonas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/antagonistas & inibidores , Linhagem Celular , Cromatina/metabolismo , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Proteínas de Ligação a DNA/antagonistas & inibidores , Proteínas Ativadoras de GTPase/genética , Proteínas Ativadoras de GTPase/metabolismo , Histonas/genética , Cinética , Metilnitronitrosoguanidina/farmacologia , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Supressoras de Tumor/antagonistas & inibidores
14.
Cell Death Differ ; 19(2): 245-56, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21738214

RESUMO

Alkylating DNA-damage agents such as N-methyl-N'-nitro-N'-nitrosoguanidine (MNNG) trigger necroptosis, a newly defined form of programmed cell death (PCD) managed by receptor interacting protein kinases. This caspase-independent mode of cell death involves the sequential activation of poly(ADP-ribose) polymerase-1 (PARP-1), calpains, BAX and AIF, which redistributes from mitochondria to the nucleus to promote chromatinolysis. We have previously demonstrated that the BAX-mediated mitochondrial release of AIF is a critical step in MNNG-mediated necroptosis. However, the mechanism regulating BAX activation in this PCD is poorly understood. Employing mouse embryonic knockout cells, we reveal that BID controls BAX activation in AIF-mediated necroptosis. Indeed, BID is a link between calpains and BAX in this mode of cell death. Therefore, even if PARP-1 and calpains are activated after MNNG treatment, BID genetic ablation abolishes both BAX activation and necroptosis. These PCD defects are reversed by reintroducing the BID-wt cDNA into the BID(-/-) cells. We also demonstrate that, after MNNG treatment, BID is directly processed into tBID by calpains. In this way, calpain non-cleavable BID proteins (BID-G70A or BID-Δ68-71) are unable to promote BAX activation and necroptosis. Once processed, tBID localizes in the mitochondria of MNNG-treated cells, where it can facilitate BAX activation and PCD. Altogether, our data reveal that, as in caspase-dependent apoptosis, BH3-only proteins are key regulators of caspase-independent necroptosis.


Assuntos
Fator de Indução de Apoptose/metabolismo , Apoptose , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Proteína X Associada a bcl-2/metabolismo , Animais , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Proteína 11 Semelhante a Bcl-2 , Calpaína/metabolismo , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Embrião de Mamíferos/citologia , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Lentivirus/genética , Proteínas de Membrana/metabolismo , Metilnitronitrosoguanidina/farmacologia , Camundongos , Modelos Biológicos , Necrose , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transdução Genética , Proteína de Morte Celular Associada a bcl/metabolismo
15.
Clin Oral Implants Res ; 23(1): 49-54, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21504480

RESUMO

OBJECTIVES: The aim of the present multi-center study was to evaluate the treatment outcome of immediately restored one-piece single-tooth implants with a diameter of 3 mm after 1 year. MATERIAL AND METHODS: A total of 57 one-piece implants (NobelDirect 3.0) were inserted in 47 patients (26 females, 21 males) with a mean age of 31 years (range: 17-76 years) at five different centers. The implants replaced maxillary lateral incisors and mandibular incisors. The implants were placed either in conjunction with tooth extraction or in healed sites, and all implants were immediately restored with a provisional resin crown. If needed, the abutment part of the implant was prepared before crown cementation. The permanent crown was placed after 1.9-14.5 months. Radiographs were taken at implant insertion as well as after 6 and 12 months to evaluate the peri-implant marginal bone level and bone loss. Moreover, plaque, bleeding on probing and complications were assessed. RESULTS: A total of 44 patients (23 females, 21 males) with 54 implants were available for the 1-year follow-up. One implant was lost, thus the 1-year implant survival was 98%. A statistically significant mean marginal bone loss was observed between baseline and 6 months (1.1 mm, range: -0.7 to 4.4 mm; n=49) and between baseline and 12 months (1.6 mm, range: -0.8 to 4.6 mm; n=50). A total of 18% of the implants were characterized by a bone loss of more than 3 mm. No bleeding on probing was observed around 83% of the implants. Plaque was registered at 15% of the implants. The most common complications were related to the provisional crown, i.e. fracture (n=3) and loss of retention (n=3). CONCLUSIONS: A high 1-year implant survival was observed in the present study. However, the excessive peri-implant marginal bone loss around several implants indicates that this implant should be used with caution until further studies have been conducted.


Assuntos
Implantes Dentários para Um Único Dente , Incisivo/cirurgia , Adolescente , Adulto , Idoso , Perda do Osso Alveolar/etiologia , Colágeno , Planejamento de Prótese Dentária , Retenção em Prótese Dentária , Prótese Dentária Fixada por Implante , Restauração Dentária Temporária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minerais , Politetrafluoretileno , Estudos Prospectivos , Estatísticas não Paramétricas , Retalhos Cirúrgicos , Extração Dentária , Resultado do Tratamento
16.
Gut ; 59(11): 1476-84, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20947883

RESUMO

BACKGROUND AND AIMS: The intestinal microbiota plays a critical role in maintaining human health; however, the mechanisms governing the normal homeostatic number and composition of these microbes are largely unknown. Previously it was shown that intestinal alkaline phosphatase (IAP), a small intestinal brush border enzyme, functions as a gut mucosal defence factor limiting the translocation of gut bacteria to mesenteric lymph nodes. In this study the role of IAP in the preservation of the normal homeostasis of the gut microbiota was investigated. METHODS: Bacterial culture was performed in aerobic and anaerobic conditions to quantify the number of bacteria in the stools of wild-type (WT) and IAP knockout (IAP-KO) C57BL/6 mice. Terminal restriction fragment length polymorphism, phylogenetic analyses and quantitative real-time PCR of subphylum-specific bacterial 16S rRNA genes were used to determine the compositional profiles of microbiotas. Oral supplementation of calf IAP (cIAP) was used to determine its effects on the recovery of commensal gut microbiota after antibiotic treatment and also on the colonisation of pathogenic bacteria. RESULTS: IAP-KO mice had dramatically fewer and also different types of aerobic and anaerobic microbes in their stools compared with WT mice. Oral supplementation of IAP favoured the growth of commensal bacteria, enhanced restoration of gut microbiota lost due to antibiotic treatment and inhibited the growth of a pathogenic bacterium (Salmonella typhimurium). CONCLUSIONS: IAP is involved in the maintenance of normal gut microbial homeostasis and may have therapeutic potential against dysbiosis and pathogenic infections.


Assuntos
Fosfatase Alcalina/fisiologia , Intestino Delgado/enzimologia , Intestino Delgado/microbiologia , Metagenoma/fisiologia , Administração Oral , Fosfatase Alcalina/deficiência , Fosfatase Alcalina/farmacologia , Animais , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Bactérias Aeróbias Gram-Negativas/isolamento & purificação , Bactérias Anaeróbias Gram-Negativas/isolamento & purificação , Homeostase/fisiologia , Metagenoma/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Filogenia , Polimorfismo de Fragmento de Restrição , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento
17.
Int J Dent Hyg ; 5(2): 87-94, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17461960

RESUMO

INTRODUCTION: In implants, maintenance assumes an important role. The role of chlorhexidine (CHX) is well known in maintenance, while only limited evidence exists on the practical use of hyaluronic acid (HA). The objective of this study was to compare the health status of the peri-implant complex (hard and soft tissues surrounding the implant) during the healing period of immediate function implants, using HA or CHX gels in the patient's maintenance protocol. STUDY POPULATION AND METHODOLOGY: Thirty complete edentulous patients, with four immediate function Brånemark System implants placed in the mandible (total of 120 implants), were randomly assigned to two groups (HA and CHX) using only these two chemicals in their daily implant self-care. Both groups were followed up for 6 months, with clinical observations on the 10th day, 2 months, 4 months and 6 months post-surgically. RESULTS: During the course of the study, HA and CHX produced good results in maintaining a healthy peri-implant complex in immediate function implants for complete rehabilitations in the edentulous mandible. Statistically significant differences were found in favour of the HA group in the modified bleeding index on the second observation (P = 0.003). The difference was more marked in the axial implants placed in the fifth sextant (P = 0.05). Correlation coefficient between plaque and bleeding index revealed a potentially better result for CHX at 6 months. CONCLUSION: The findings point out the importance of a maintenance protocol in immediate function implants. Both chemicals are valid tools for implant maintenance. The authors suggest that it might be advantageous to administer HA in the first 2 months and CHX between 2 and 6 months.


Assuntos
Anti-Infecciosos Locais/administração & dosagem , Clorexidina/administração & dosagem , Implantação Dentária Endóssea/métodos , Implantes Dentários , Profilaxia Dentária/métodos , Ácido Hialurônico/administração & dosagem , Cicatrização/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda do Osso Alveolar/diagnóstico por imagem , Prótese Total Imediata , Prótese Total Inferior , Método Duplo-Cego , Feminino , Géis , Humanos , Masculino , Pessoa de Meia-Idade , Índice Periodontal , Projetos Piloto , Radiografia , Estatísticas não Paramétricas
18.
Int J Dent Hyg ; 4(2): 84-90, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16637910

RESUMO

INTRODUCTION: Peri-implant pathologies consist of an inflammatory process affecting the soft and hard tissues surrounding the implants. Chlorhexidine is considered the gold standard antiseptic, with a large variety of choice in administration. In this study, a protocol for the irrigation of peri-implant pockets with a chlorhexidine gel, using a plastic needle for the delivery of the product into the peri-implant pockets is described. STUDY PARTICIPANTS AND METHODS: Nine patients with at least one implant presenting peri-implant pathology (inflamed soft tissue associated with bone loss around the implant) were enrolled in this prospective clinical study, and followed-up for 1 year, where clinical parameters such as modified plaque index, modified bleeding index, probing pocket depths, attachment levels were assessed at baseline, 1 month, and 1 year after implementation of the treatment protocol. RESULTS: Treatment success was achieved in eight of the nine patients (and in 11 of the 13 implants) according to the success criteria adopted by the authors of this study. DISCUSSION: Infection control lies at the heart of peri-implant treatment. The control of three factors such as optimal diagnosis, removal of the aetiological factor of the disease (proper removal of debris and decontamination of the peri-implant sulcus/pocket) and a good patient's oral hygiene self-care represents the key to success, resulting in good treatment outcomes when managing peri-implant pathologies. The protocol used (irrigation of peri-implant pockets with chlorhexidine gel delivered by a plastic needle) is considered to be of utility.


Assuntos
Perda do Osso Alveolar/tratamento farmacológico , Anti-Infecciosos Locais/administração & dosagem , Clorexidina/administração & dosagem , Implantes Dentários/efeitos adversos , Bolsa Periodontal/tratamento farmacológico , Idoso , Perda do Osso Alveolar/etiologia , Equipamentos Descartáveis , Feminino , Géis , Gengivite/tratamento farmacológico , Gengivite/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Agulhas , Índice Periodontal , Bolsa Periodontal/etiologia , Estudos Prospectivos , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/etiologia , Irrigação Terapêutica/instrumentação
19.
Rev. psiquiatr. infanto-juv ; 22(4): 164-170, oct.-dic. 2005. tab, graf
Artigo em Es | IBECS | ID: ibc-051265

RESUMO

El problema de la cooperación social es central para la naturaleza humana. En este estudio la evaluamos en pacientes con trastorno por déficit de atención y trastorno negativista desafiante (TDAH-TND). Usaremos para ello diseñado por nuestro equipo, llamado Dilema del Prisionero por ordenador para evaluar cooperación (DPOC). Este test intenta evitar los sesgos de respuesta en tests de lápiz y papel mediante una simulación de situaciones de intercambio social. Las comparaciones de estos niños con un grupo control muestran que el patrón de respuesta es completamente caótico y por tanto no cooperador sin un tratamiento que logre estabilización (entendiendo como tal una mejoría de 4 puntos en una escala Likert de 7 valorada por los padres y puntuaciones en escalas de Conners y Eyberg por debajo de puntos de corte para patología). Una vez estabilizados con metilfenidato a dosis de 0,6-1 mg/kg más psicoterapia aparece respecto a un grupo control de la comunidad un patrón de respuestas más errático y menos cooperativo, con respuestas más impulsivas y más dificultad para entender el test cuando este se vuelve más complejo


Concept of cooperation in essential for understanding human nature. In our study we evaluate cooperation in patients with attention deficit disorder with hyperactivity plus defiant disorder (ADH+DD). We used a test designed by us, called computerised Prisoners' dilemma to evaluate cooperation (DPOC). This test tries to avoid response bias in test based on questionnaires with a simulation by computer of a social interchange. Comparisons of ADHD+DD with community control group show that their cooperative behaviour is chaotic in absence of a treatment stabilization (defined as an improvement of 4 in a Likert scale for parents and a score below diagnosis point in Conners and Eyberg test). Once stabilization was reached with metilphenidate 0,6- lmg/kg plus psycotherapy, ADHD+DD case have a more erratic and less cooperative behavior than a control group, with more impulsive responses and difficulty to understand the test when it becomes more complex


Assuntos
Masculino , Pré-Escolar , Criança , Adolescente , Humanos , Comportamento Cooperativo , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Teoria dos Jogos , Testes Psicológicos/estatística & dados numéricos , Negativismo , Psicoterapia , Estudos de Casos e Controles
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