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1.
Lung Cancer ; 181: 107254, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37253296

RESUMO

KRAS G12C mutations are found in about 12-13% of LUAD samples and it is unclear whether they are associated with worse survival outcomes in resected, stage I LUAD. We assessed whether KRAS-G12C mutated tumours had worse DFS when compared to KRAS-nonG12C mutated tumours and to KRAS wild-type tumours in a cohort of resected, stage I LUAD (IRE cohort). We then leveraged on publicly available datasets (TCGA-LUAD, MSK-LUAD604) to further test the hypothesis in external cohorts. In the stage I IRE cohort we found a significant association between the KRAS-G12C mutation and worse DFS in multivariable analysis (HR: 2.47). In the TCGA-LUAD stage I cohort we did not find statistically significant associations between the KRAS-G12C mutation and DFS. In the MSK-LUAD604 stage I cohort we found that KRAS-G12C mutated tumours had worse RFS when compared to KRAS-nonG12C mutated tumours in univariable analysis (HR 3.5). In the pooled stage I cohort we found that KRAS-G12C mutated tumours had worse DFS when compared to KRAS-nonG12C mutated tumours (HR 2.6), to KRAS wild-type tumours (HR 1.6) and to any other tumours (HR 1.8); in multivariable analysis, the KRAS-G12C mutation was associated with worse DFS (HR 1.61). Our results suggest that patients with resected, stage I LUAD with a KRAS-G12C mutation may have inferior survival outcomes..


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Proteínas Proto-Oncogênicas p21(ras)/genética , Prognóstico , Neoplasias Pulmonares/patologia , Mutação
4.
Ann Oncol ; 31(12): 1746-1754, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32866624

RESUMO

BACKGROUND: Immune checkpoint inhibitors (ICIs) have demonstrated significant overall survival (OS) benefit in lung adenocarcinoma (LUAD). Nevertheless, a remarkable interpatient heterogeneity characterizes immunotherapy efficacy, regardless of programmed death-ligand 1 (PD-L1) expression and tumor mutational burden (TMB). KEAP1 mutations are associated with shorter survival in LUAD patients receiving chemotherapy. We hypothesized that the pattern of KEAP1 co-mutations and mutual exclusivity may identify LUAD patients unresponsive to immunotherapy. PATIENTS AND METHODS: KEAP1 mutational co-occurrences and somatic interactions were studied in the whole MSKCC LUAD dataset. The impact of coexisting alterations on survival outcomes in ICI-treated LUAD patients was verified in the randomized phase II/III POPLAR/OAK trials (blood-based sequencing, bNGS cohort, N = 253). Three tissue-based sequencing studies (Rome, MSKCC and DFCI) were used for independent validation (tNGS cohort, N = 289). Immunogenomic features were analyzed using The Cancer Genome Atlas (TCGA) LUAD study. RESULTS: On the basis of KEAP1 mutational co-occurrences, we identified four genes potentially associated with reduced efficacy of immunotherapy (KEAP1, PBRM1, SMARCA4 and STK11). Independent of the nature of co-occurring alterations, tumors with coexisting mutations (CoMut) had inferior survival as compared with single-mutant (SM) and wild-type (WT) tumors (bNGS cohort: CoMut versus SM log-rank P = 0.048, CoMut versus WT log-rank P < 0.001; tNGS cohort: CoMut versus SM log-rank P = 0.037, CoMut versus WT log-rank P = 0.006). The CoMut subset harbored higher TMB than the WT disease and the adverse significance of coexisting alterations was maintained in LUAD with high TMB. Significant immunogenomic differences were observed between the CoMut and WT groups in terms of core immune signatures, T-cell receptor repertoire, T helper cell signatures and immunomodulatory genes. CONCLUSIONS: This study indicates that coexisting alterations in a limited set of genes characterize a subset of LUAD unresponsive to immunotherapy and with high TMB. An immune-cold microenvironment may account for the clinical course of the disease.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/terapia , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Humanos , Imunoterapia , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Mutação , Fator 2 Relacionado a NF-E2 , Ensaios Clínicos Controlados Aleatórios como Assunto , Microambiente Tumoral
5.
Cancer Treat Rev ; 70: 41-46, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30077081

RESUMO

In renal cancer emerging treatment options are becoming available and there is a strong need to combine therapies to reformulate and adjourn clinical practice. We here highlight and discuss the need to take advantage of the common immune targets to design combined strategies to increase clinical responses.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Imunoterapia , Neoplasias Renais/imunologia , Neoplasias Renais/prevenção & controle , Humanos , Prognóstico
6.
Pharmacogenomics J ; 16(4): 320-5, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26216193

RESUMO

5-Fluorouracil is among the most widely used anticancer drug, but a fraction of treated patients develop severe toxicity, with potentially lethal injuries. The predictive power of the available pretreatment assays, used to identify patients at risk of severe toxicity, needs improvements. This study aimed to correlate a phenotypic marker of 5-fluorouracil metabolism (the individual degradation rate of 5-fluorouracil-5-FUDR) with 15 functional polymorphisms in the dihydropyrimidine dehydrogenase gene (DPYD). Single SNP (single-nucleotide polymorphism) analysis revealed that the SNPs rs1801160, rs1801265, rs2297595 and rs3918290 (splice site variant IVS14+1G>A) were significantly associated with a decreased value of 5-FUDR, and the rs3918290 causing the larger decrease. Multi-SNP analysis showed that a three-SNP haplotype (Hap7) involving rs1801160, rs1801265 and rs2297595 causes a marked decrease in 5-FUDR, comparable to that caused by the splice site variant rs3918290, which is the main pharmacogenetic marker associated with severe fluorouracil toxicity. The similar effect played by Hap7 and by the splice site variant rs3918290 upon individual 5-FUDR suggests that Hap7 could also represent a similar determinant of fluorouracil toxicity. Haplotype assessment could improve the predictive value of DPYD genetic markers aimed at the pre-emptive identification of patients at risk of severe 5-fluorouracil toxicity.The Pharmacogenomics Journal advance online publication, 28 July 2015; doi:10.1038/tpj.2015.56.


Assuntos
Antimetabólitos Antineoplásicos/metabolismo , Di-Hidrouracila Desidrogenase (NADP)/genética , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/genética , Fluoruracila/metabolismo , Variantes Farmacogenômicos/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Di-Hidrouracila Desidrogenase (NADP)/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/enzimologia , Feminino , Fluoruracila/efeitos adversos , Frequência do Gene , Estudos de Associação Genética , Haplótipos , Humanos , Inativação Metabólica , Masculino , Pessoa de Meia-Idade , Testes Farmacogenômicos , Fenótipo , Valor Preditivo dos Testes , Fatores de Risco
7.
Colorectal Dis ; 15(7): e382-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23581854

RESUMO

AIM: Preoperative chemoradiation (CRT) for rectal cancer decreases the number of examined lymph nodes (NELN) found in the resected specimen. However, the prognostic role of lymph node evaluation including overall numbers and the lymph node ratio (LNR) in patients having preoperative CRT have not yet been defined. The study has assessed the influence of CRT on the NELN and on lymph node number and LNR on the survival of patients with rectal cancer. METHOD: Between 2003 and 2011, 508 patients with nonmetastatic rectal cancer underwent mesorectal excision. Of these 123 (24.2%) received preoperative CRT. Univariate and multivariate analysis was performed to define the role of NELN and LNR as prognostic indicators of survival. RESULTS: Neoadjuvant CRT significantly reduced the NELN (P < 0.0001). Disease-free survival (DFS) and overall survival (OS) of patients with fewer or more than 12 nodes retrieved did not differ statistically. Node-negative patients with six or fewer lymph nodes were significantly associated with a poor DFS and OS on univariate analysis (P = 0.03 and P = 0.03). LNR significantly influenced the DFS and OS on multivariate analysis [DFS, P = 0.0473, hazard ratio (HR) 2.4980, 95% confidence interval (CI) 1.2631-9.4097; OS, P = 0.0419, HR 1.1820, 95% CI 1.1812-10,710]. CONCLUSION: The cut-off of 12 lymph nodes does not influence survival and should not be considered for cancer-specific prediction of patients having neoadjuvant CRT. In contrast LNR is an independent prognostic predictor of DFS and OS in such patients.


Assuntos
Carcinoma/terapia , Quimiorradioterapia Adjuvante/métodos , Excisão de Linfonodo/métodos , Linfonodos/patologia , Neoplasias Retais/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma/mortalidade , Carcinoma/patologia , Intervalo Livre de Doença , Feminino , Humanos , Linfonodos/cirurgia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Neoplasias Retais/mortalidade , Neoplasias Retais/patologia , Fatores de Tempo
8.
J Ultrasound ; 16(3): 127-30, 2013 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-24432163

RESUMO

In Western countries, breast cancer is the most common cancer in women, whereas metastases to the breast from extramammary malignancies are extremely rare. We present the case of a 60-year-old woman, who underwent surgery in 2007 for clear cell renal cell carcinoma and who 4 years later presented with a breast metastasis from clear cell renal cell carcinoma.

9.
Oral Dis ; 16(2): 160-6, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20374503

RESUMO

OBJECTIVE: The aim of this comparative study was to analyze cytopathologically and chemico-physically the mucosa surrounding oral piercing to correlate results with adverse tissue signs. MATERIALS AND METHODS: The tongue superficial mucosa of 15 young subjects (control group) and the superficial mucosa surrounding oral piercing of 15 young subjects (test group, TG) were smeared on slides, Papanicolaou stained and analyzed under the optical microscope. Some smears were prepared for (back-scattered) scanning electron microscope (SEM) and X-ray microanalysis to study piercing fragments. RESULTS: Smears of TG displayed a variable extent of bacterial cytolysis of epithelial cells, fungi, hyperkeratosis, parakeratosis, granulocyte infiltration, calcium formations and bacterial flora; the four last statistically significant (P < 0.05). Foreign bodies surrounded by keratinocytes were detected under both light and SEM. X-ray microanalyses highlighted piercing alloy aggression, ion release and an inverse gradient of ion concentration inside keratinocytes. CONCLUSIONS: The pathological findings in smears correlated with adverse effects of oral piercing. Ion release may be related to direct toxic effects and belated reactions because of metal sensitization. A strict regulation of piercing is warranted.


Assuntos
Piercing Corporal , Citodiagnóstico , Mucosa Bucal/patologia , Adulto , Consumo de Bebidas Alcoólicas , Bactérias/isolamento & purificação , Calcinose/patologia , Corantes , Microanálise por Sonda Eletrônica , Células Epiteliais/patologia , Feminino , Corpos Estranhos/patologia , Fungos/isolamento & purificação , Granulócitos/patologia , Humanos , Queratinócitos/patologia , Leucoplasia Oral/patologia , Masculino , Metais/análise , Microscopia Eletrônica de Varredura , Mucosa Bucal/química , Mucosa Bucal/microbiologia , Fumar , Fatores de Tempo , Língua/patologia , Adulto Jovem
10.
J Clin Dent ; 20(3): 103-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19711612

RESUMO

OBJECTIVE: The objective of the present clinical study was to assess the effect of the use of a dentifrice containing triclosan on peri-implant mucositis in subjects that had been restored with dental implants. METHODS: The trial was designed as a double-blind, randomized, two-treatment, parallel-group clinical study. Sixty male and female subjects, aged 30-70 years, were recruited. All subjects had lost teeth due to periodontal disease, and had been restored with a minimum of two implants at least one year prior to the start of the trial. Subjects were randomly assigned to two treatment groups. The subjects in the test group (Test) brushed their teeth and implant-supported restorations with a dentifrice containing triclosan, while the control subjects brushed with a sodium fluoride dentifrice. Only subjects with a minimum of one implant site showing clinical signs of peri-implant mucositis, i.e., bleeding after probing, were enrolled in the study. Clinical examinations were performed at baseline, and after three and six months. The following parameters were scored: Probing pocket depth (PPD), bleeding on probing (BoP), and plaque. The change from baseline within each treatment group at three months and six months was evaluated for all parameters using ANOVA and ANCOVA. RESULTS: Subjects with peri-implant mucositis who used a dentifrice containing 0.3% triclosan, as an adjunct to mechanical tooth brushing, exhibited significantly fewer clinical signs of inflammation than subjects who used a regular fluoride dentifrice at six months. The BoP scores were reduced from 53.8% to 29.1% in the Test group, whereas in the same interval there was an increase from 52.3% to 58.8% in the Control group. Furthermore, the individual mean PPD, as well as the frequency of sites with 5 mm and > or = 6 mm deep pockets, were reduced significantly more in the Test than in the Control group. CONCLUSION: The regular use of a dentifrice containing triclosan may reduce the clinical signs of inflammation in the mucosa adjacent to dental implants.


Assuntos
Anti-Infecciosos Locais/farmacologia , Implantes Dentários/efeitos adversos , Dentifrícios/farmacologia , Mucosite/tratamento farmacológico , Triclosan/farmacologia , Adulto , Idoso , Análise de Variância , Misturas Complexas , Índice de Placa Dentária , Método Duplo-Cego , Feminino , Fluoretos , Humanos , Masculino , Pessoa de Meia-Idade , Mucosite/etiologia , Índice Periodontal , Ácido Silícico , Cremes Dentais , Resultado do Tratamento
11.
Br J Pharmacol ; 150(5): 595-603, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17245369

RESUMO

BACKGROUND AND PURPOSE: In circulatory shock, melanocortins have life-saving effects likely to be mediated by MC4 receptors. To gain direct insight into the role of melanocortin MC4 receptors in haemorrhagic shock, we investigated the effects of two novel selective MC4 receptor agonists. EXPERIMENTAL APPROACH: Severe haemorrhagic shock was produced in rats under general anaesthesia. Rats were then treated with either the non-selective agonist [Nle4, D-Phe7]-melanocyte-stimulating hormone (NDP--MSH) or with the selective MC4 agonists RO27-3225 and PG-931. Cardiovascular and respiratory functions were continuously monitored for 2 h; survival rate was recorded up to 24 h. Free radicals in blood were measured using electron spin resonance spectrometry; tissue damage was evaluated histologically 25 min or 24 h after treatment. KEY RESULTS: All shocked rats treated with saline died within 30-35 min. Treatment with NDP--MSH, RO27-3225 and PG-931 produced a dose-dependent (13-108 nmol kg-1 i.v.) restoration of cardiovascular and respiratory functions, and improved survival. The three melanocortin agonists also markedly reduced circulating free radicals relative to saline-treated shocked rats. All these effects were prevented by i.p. pretreatment with the selective MC4 receptor antagonist HS024. Moreover, treatment with RO27-3225 prevented morphological and immunocytochemical changes in heart, lung, liver, and kidney, at both early (25 min) and late (24 h) intervals. CONCLUSIONS AND IMPLICATIONS: Stimulation of MC4 receptors reversed haemorrhagic shock, reduced multiple organ damage and improved survival. Our findings suggest that selective MC4 receptor agonists could have a protective role against multiple organ failure following circulatory shock.


Assuntos
Insuficiência de Múltiplos Órgãos/prevenção & controle , Peptídeos Cíclicos/farmacologia , Receptor Tipo 4 de Melanocortina/agonistas , Choque Hemorrágico/tratamento farmacológico , alfa-MSH/análogos & derivados , Animais , Pressão Sanguínea/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Radicais Livres/sangue , Frequência Cardíaca/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Insuficiência de Múltiplos Órgãos/metabolismo , Insuficiência de Múltiplos Órgãos/patologia , Insuficiência de Múltiplos Órgãos/fisiopatologia , Miocárdio/patologia , Peptídeos Cíclicos/uso terapêutico , Ratos , Ratos Wistar , Receptor Tipo 4 de Melanocortina/metabolismo , Mecânica Respiratória , Índice de Gravidade de Doença , Choque Hemorrágico/metabolismo , Choque Hemorrágico/patologia , Choque Hemorrágico/fisiopatologia , Fatores de Tempo , alfa-MSH/farmacologia , alfa-MSH/uso terapêutico
12.
Int J Comput Dent ; 8(2): 117-27, 2005 Apr.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-16201396

RESUMO

INTRODUCTION: The teaching of manual skills and competencies is among the most time-consuming aspects of oral health-care education, especially when large groups of students are involved. Video has been repeatedly used as an educational tool with varying results. PURPOSE: The present study aimed to investigate the effectiveness of a computer-based video support system during practical training of manual skills and competencies related to periodontal treatment. MATERIALS AND METHODS: Eighty-four students were randomized into 9 groups: 5 experimental and 4 control groups. The control groups received instruction in the use of scaling and root planing instruments during a 7-hour seminar, and 2 hours of manual practice. The experimental groups received the same instruction, but in addition had access to a computer-based video support system, the Visual Training System (VTS), during practical training. During the 2-hour long practice session, all students practiced 21 different procedures, which were video recorded. The videos were later evaluated by an independent observer. RESULTS: On the whole, the students in the experimental group performed significantly better than their colleagues in the control group. Specifically, the groups that utilized the VTS video support performed significantly better in 9 of the 21 procedures tested. CONCLUSION: These results suggest that this computer-based video support can be an effective aid in the teaching of manual skills related to oral health care.


Assuntos
Competência Clínica , Instrução por Computador , Hipermídia , Manequins , Destreza Motora/fisiologia , Doenças Periodontais/terapia , Ensino/métodos , Adulto , Assistentes de Odontologia/educação , Higienistas Dentários/educação , Raspagem Dentária , Retroalimentação , Feminino , Humanos , Aprendizagem , Masculino , Pessoa de Meia-Idade , Periodontia/educação , Aplainamento Radicular , Gravação em Vídeo
13.
J Mater Sci Mater Med ; 16(9): 789-93, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16167106

RESUMO

The work aims to provide a histological investigation of Fisiograft, a PLA/PGA copolymer, used as filler for bone defects in humans. The study was performed on biopsies of sinus lifts where Bio-Oss and Fisiograft gel were applied as graft material. Bone regeneration was satisfactory in all sinus lifts, even when Fisiograft was applied alone. Due to remarkable osteoclast activity, Bio-Oss granules were cleared from the majority of biopsy cores. At histology, Fisiograft gel appeared as globes enveloped by fibroblasts, displaying an epithelial-like cell appearance. Due to its solubility in solvents, undegraded Fisiograft (recorded for 7 months or more) did not stain whereas degraded Fisiograft stained positive. The loose connective tissue, that surrounded Fisiograft and bone contained isolated mastocytes. Bone grew inside the loose connective and often reached the surface of Fisiograft by intervening cells. The results seem to indicate that Fisiograft may be considered both a polymer useful for fastening bone substitutes inside a defect and in addition a material capable of prompting bone regeneration, with or without the use of a bone substitute. In addition to space-former and space-maintainer functions, Fisiograft shows potential bone stimulation function, which may be labelled as osteopromotive capability.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/uso terapêutico , Regeneração Tecidual Guiada , Minerais/uso terapêutico , Osseointegração , Autorradiografia , Materiais Biocompatíveis , Biópsia , Substitutos Ósseos/química , Quimioterapia Combinada , Feminino , Fibroblastos/citologia , Seguimentos , Géis , Humanos , Ácido Láctico/química , Ácido Láctico/uso terapêutico , Masculino , Mastócitos/citologia , Seio Maxilar/cirurgia , Pessoa de Meia-Idade , Osteoclastos/citologia , Osteoclastos/metabolismo , Osteogênese , Poliglactina 910/química , Poliglactina 910/uso terapêutico , Ácido Poliglicólico/química , Ácido Poliglicólico/uso terapêutico , Polímeros , Solubilidade , Coloração e Rotulagem , Fatores de Tempo
14.
Eur J Dent Educ ; 9(2): 53-8, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15811151

RESUMO

BACKGROUND: Video-based instructions for clinical procedures have been used frequently during the preceding decades. AIM: To investigate in a randomised controlled trial the learning effectiveness of fragmented videos vs. the complete sequential video and to analyse the attitudes of the user towards video as a learning aid. MATERIALS AND METHODS: An instructional video on surgical hand wash was produced. The video was available in two different forms in two separate web pages: one as a sequential video and one fragmented into eight short clips. Twenty-eight dental students in the second semester were randomised into an experimental (n = 15) and a control group (n = 13). The experimental group used the fragmented form of the video and the control group watched the complete one. The use of the videos was logged and the students were video taped whilst undertaking a test hand wash. The videos were analysed systematically and blindly by two independent clinicians. The students also performed a written test concerning learning outcome from the videos as well as they answered an attitude questionnaire. RESULTS: The students in the experimental group watched the video significantly longer than the control group. There were no significant differences between the groups with regard to the ratings and scores when performing the hand wash. The experimental group had significantly better results in the written test compared with those of the control group. There was no significant difference between the groups with regard to attitudes towards the use of video for learning, as measured by the Visual Analogue Scales. Most students in both groups expressed satisfaction with the use of video for learning. CONCLUSION: The students demonstrated positive attitudes and acceptable learning outcome from viewing CAL videos as a part of their pre-clinical training. Videos that are part of computer-based learning settings would ideally be presented to the students both as a segmented and as a whole video to give the students the option to choose the form of video which suits the individual student's learning style.


Assuntos
Instrução por Computador , Educação em Odontologia/métodos , Desinfecção das Mãos , Cirurgia Bucal/educação , Gravação de Videoteipe/métodos , Atitude do Pessoal de Saúde , Avaliação Educacional , Humanos , Estudantes de Odontologia/psicologia , Inquéritos e Questionários
15.
Dent Traumatol ; 20(3): 172-7, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15144450

RESUMO

Traumatized anterior teeth need quick esthetic and functional repair. Esthetic requirements of anterior teeth require the use of composite materials which, in the most complex cases, can be used in association with fibers so as to improve their mechanical resistance. Many kinds of fibers are available. The authors considered parameters such as physical properties, water absorption, ease of cutting and of laying. Polyethylene fibers appear to have the best properties in elasticity, translucency, adaptability, tenaciousness, resistance to traction and to impact. Fifteen children, between 7 and 13 years old, with crown fractures of the anterior sector were treated. In the case of a simple crown fracture, the missing part was restored by polyethylene fibers and composite resins. In the case of a complex crown fracture needing endodontic treatment, the fibers were used as a central core stump in order to restore the dental morphology. At control examinations, the teeth restored by this technique were acceptable, both in function and in aesthetics. Thus, the authors recommend this combined technique for predictable restoration of traumatized anterior teeth.


Assuntos
Resinas Compostas/química , Materiais Dentários/química , Restauração Dentária Permanente/métodos , Incisivo/lesões , Polietilenos/química , Coroa do Dente/lesões , Fraturas dos Dentes/terapia , Adolescente , Criança , Estética Dentária , Humanos , Técnica para Retentor Intrarradicular , Tratamento do Canal Radicular , Estresse Mecânico , Propriedades de Superfície
16.
J Pharmacol Exp Ther ; 297(3): 1082-7, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11356932

RESUMO

The influence of the melanocortin peptide ACTH-(1-24) (adrenocorticotropin) on the consequences of short-term coronary ischemia (5 min) followed by reperfusion, and the effect of the long-acting melanocortin [Nle(4),D-Phe(7)]alpha-melanocyte-stimulating hormone (NDP-MSH) on the damage induced by a permanent coronary occlusion, were investigated in anesthetized rats. Ischemia was produced by ligature of the left anterior descending coronary artery. Reperfusion-induced arrhythmias [ventricular tachycardia (VT), ventricular fibrillation (VF)] and survival rate within the 5 min following reperfusion, blood levels of free radicals detected 2 min after reperfusion by electron spin resonance spectrometry, and amount of healthy myocardial tissue, measured 72 h after permanent coronary occlusion on immunohistologically stained serial sections, were evaluated. Postischemic reperfusion induced VT in all saline-treated rats, and VF and death in a high percentage of animals (87%). In rats treated i.v. (2.5 min after coronary occlusion) with ACTH-(1-24) (0.16-0.48 mg/kg) there was a significantly dose-dependent reduction in the incidence of arrhythmias and lethality. Ischemia/reperfusion caused a large increase in free radical blood levels; treatment with ACTH-(1-24) (0.48 mg/kg i.v.) almost completely prevented this increase. In rats subjected to permanent coronary occlusion, the amount of healthy myocardial tissue was much reduced in saline-treated rats, while in rats treated s.c. with NDP-MSH (0.27 mg/kg every 12 h) it was significantly higher. The present data demonstrate, for the first time, an unforeseen property of melanocortin peptides, i.e., their ability to significantly reduce both heart ischemia/reperfusion injury and size of the ischemic area induced by permanent coronary occlusion.


Assuntos
Doença das Coronárias/tratamento farmacológico , Cosintropina/administração & dosagem , Isquemia Miocárdica/tratamento farmacológico , Neuropeptídeos/administração & dosagem , alfa-MSH/administração & dosagem , Animais , Arritmias Cardíacas/prevenção & controle , Doença das Coronárias/metabolismo , Relação Dose-Resposta a Droga , Esquema de Medicação , Eletrocardiografia/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Feminino , Radicais Livres/antagonistas & inibidores , Radicais Livres/sangue , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/patologia , Reperfusão Miocárdica , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Taxa de Sobrevida , alfa-MSH/análogos & derivados
17.
Eur J Pharmacol ; 397(1): 75-84, 2000 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-10844101

RESUMO

The effect of gamma-hydroxybutyrate on the histological and behavioral consequences of transient brain ischemia was studied in the four vessel occlusion rat model. In saline-treated animals, 30 min ischemia caused a massive loss of neurons in the hippocampal CA1 subfield (normal neurons: 14%, 5%, 23% and 30% on the 3rd, 10th, 15th and 65th day after ischemia, respectively). gamma-Hydroxybutyrate - 300 mg/kg intraperitoneally (i.p.) 30 min before or 10 min after arteries occlusion, followed by 100 mg/kg i.p. twice daily for the following 10 days - afforded a highly significant protection (normal neurons on the 3rd, 10th, 15th and 65th day after ischemia: 88% and 91%, 80% and 80%, 91% and 90%, 72% and 71% in rats receiving the first dose before or after arteries occlusion, respectively). The ischemia-induced sensory-motor impairment was significantly attenuated in rats receiving the first dose of gamma-hydroxybutyrate before arteries occlusion. Finally, the ischemia-induced impairment in spatial learning and memory, evaluated starting 27 days after the ischemic episode, was significantly attenuated by gamma-hydroxybutyrate, either injected first at 30 min before or 10 min after arteries occlusion. Lower doses of gamma-hydroxybutyrate had no significant effect. In conclusion, these results indicate that gamma-hydroxybutyrate provides significant protection against both histological and behavioral consequences of transient global cerebral ischemia in rats.


Assuntos
Isquemia Encefálica/fisiopatologia , Hipocampo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Oxibato de Sódio/farmacologia , Animais , Hipocampo/patologia , Aprendizagem/efeitos dos fármacos , Masculino , Memória/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Wistar , Córtex Somatossensorial/efeitos dos fármacos , Córtex Somatossensorial/fisiopatologia , Comportamento Espacial/efeitos dos fármacos
18.
Clin Oral Implants Res ; 10(1): 62-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10196791

RESUMO

In order to ensure an adequate space where new bone can be formed in guided bone regeneration (GBR), most surgeons fill bone defects with biomaterials. In this work we evaluated new bone regeneration in 10 patients using only a blood clot protected with titanium grids and non-resorbable membranes, without any filling material. A manual measurement of the size of the bone defect, using a plastic probe, was performed at 2 surgical steps. After 5 months of treatment, a biopsy was taken from each patient, fixed and embedded in PMMA, examined microradiographically and morphologically to evaluate the newly-formed bone. Our results showed a good repair of the defects by bone regeneration (about 85% overall), high mineral density of new bone around the implants after 5 months, and steady state deposition processes. These results in GBR, without filling material, appear very promising for implantology and reconstructive odontostomatology practice.


Assuntos
Perda do Osso Alveolar/cirurgia , Regeneração Óssea , Regeneração Tecidual Guiada Periodontal/instrumentação , Regeneração Tecidual Guiada Periodontal/métodos , Titânio , Adulto , Processo Alveolar/fisiologia , Coagulação Sanguínea , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Membranas Artificiais , Pessoa de Meia-Idade , Telas Cirúrgicas
19.
Eur J Histochem ; 42(1): 41-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9615190

RESUMO

Paraffin embedded and formalin fixed needle biopsies of prostate cancer (PC) were used to immunocytochemically detect the p120 nucleolar protein in relation to the Gleason histological gradings (GHG), the labelling indices of proliferating nuclear immunocytochemical markers (PCNA/Cyclin, Ki-67/MIB1) and the argyrophilic nucleolar region (AgNOR) rate. The twenty-six cases of PC (6 from large histological samples and 20 from needle biopsies) were equally distributed into low (< or = 6) or high (> or = 7) GHG groups. The p120 nucleolar protein immunocytochemical reaction was randomly expressed in large histological sections but uniformly distributed without gaps in needle biopsy sections. Only on the latter were quantitative values of PCNA/Cyclin (23.2 in low and 45.3 in high GHG), Ki-67/MIB1 (13.8 in low and 43.3 in high GHG) and AgNOR (5.0 in low and 7.5 in high GHG) related to those of p120 nucleolar protein (0.8 in low and 3.8 in high GHG). The values of all these cell cycle markers increased from low to high GHG of PC, all four reaching high statistical significance between the two groups (ANOVA-two tailed p < 0.0001). The PCNA/Cyclin index showed a higher positivity than the Ki-67/MIB1 index in PC with low GHG but not in PC with high GHG. In conclusion, paraffin embedded and formalin fixed PC needle biopsies exhibit a higher diagnostic PCNA/Cyclin than Ki-67/MIB1 index for cases presenting differentiated features, whereas p120 nucleolar protein detection seems to be a suitable marker of poorer outcome of PC.


Assuntos
Ciclinas/análise , Antígeno Ki-67/análise , Proteínas Nucleares/análise , Antígeno Nuclear de Célula em Proliferação/análise , Neoplasias da Próstata/diagnóstico , Idoso , Biópsia por Agulha , Ciclo Celular , Estudos de Avaliação como Assunto , Fixadores , Formaldeído , Humanos , Imuno-Histoquímica , Masculino , Inclusão em Parafina , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Coloração pela Prata , tRNA Metiltransferases
20.
Pathol Int ; 47(12): 848-53, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9503466

RESUMO

Liver histopathology of segmental portal ischemia occurring over a long-term period has not been previously described. For these reasons histological changes in the rat liver were studied from 1 h to up to 90 days after a left lateral and middle segmental portal obstruction. Within 3 h, the hepatocytes showed glycogen depletion in Rappaport zones 1 and 2 and pericentral and central lobular congestion of sinusoids and veins, whereas within 3 days, vein thrombosis appeared in the center of the lobule and liver necrosis was observed in Rappaport zones 2 or 3 or both, followed by restitutio ad integrum of the liver lobule morphology after 20-40 days. These results can be explained in light of two conditions occurring in the rat liver: (i) the peculiar low sensitivity of the liver to O2 debit and the protective or vasoactive effects used during hypoxia; and (ii) the sinusoidal network as a collateral source of the hepatic vascular system. Therefore, morphological assessment of this arteriolar and sinusoidal system, implicated in assuring efficient collateral blood supply in the rat liver with portal ischemia, is essential for understanding the mechanisms behind a natural and timely repair of ischemic injuries in the human liver.


Assuntos
Isquemia/patologia , Regeneração Hepática , Fígado/patologia , Animais , Fígado/irrigação sanguínea , Masculino , Ratos , Ratos Sprague-Dawley , Análise de Regressão , Fatores de Tempo
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