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BACKGROUND: RAS assessment is mandatory for therapy decision in metastatic colorectal cancer (mCRC) patients. This determination is based on tumor tissue, however, genotyping of circulating tumor (ct)DNA offers clear advantages as a minimally invasive method that represents tumor heterogeneity. Our study aims to evaluate the use of ctDNA as an alternative for determining baseline RAS status and subsequent monitoring of RAS mutations during therapy as a component of routine clinical practice. PATIENTS AND METHODS: RAS mutational status in plasma was evaluated in mCRC patients by OncoBEAM™ RAS CRC assay. Concordance of results in plasma and tissue was retrospectively evaluated. RAS mutations were also prospectively monitored in longitudinal plasma samples from selected patients. RESULTS: Analysis of RAS in tissue and plasma samples from 115 mCRC patients showed a 93% overall agreement. Plasma/tissue RAS discrepancies were mainly explained by spatial and temporal tumor heterogeneity. Analysis of clinico-pathological features showed that the site of metastasis (i.e. peritoneal, lung), the histology of the tumor (i.e. mucinous) and administration of treatment previous to blood collection negatively impacted the detection of RAS in ctDNA. In patients with baseline mutant RAS tumors treated with chemotherapy/antiangiogenic, longitudinal analysis of RAS ctDNA mirrored response to treatment, being an early predictor of response. In patients RAS wt, longitudinal monitoring of RAS ctDNA revealed that OncoBEAM was useful to detect emergence of RAS mutations during anti-EGFR treatment. CONCLUSION: The high overall agreement in RAS mutational assessment between plasma and tissue supports blood-based testing with OncoBEAM™ as a viable alternative for genotyping RAS of mCRC patients in routine clinical practice. Our study describes practical clinico-pathological specifications to optimize RAS ctDNA determination. Moreover, OncoBEAM™ is useful to monitor RAS in patients undergoing systemic therapy to detect resistance and evaluate the efficacy of particular treatments.
Assuntos
Neoplasias Colorretais/diagnóstico , Análise Mutacional de DNA/métodos , DNA de Neoplasias/sangue , Genes ras , Antineoplásicos/uso terapêutico , Neoplasias Colorretais/sangue , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Receptores ErbB/antagonistas & inibidores , Humanos , Monitorização Fisiológica/métodos , Metástase Neoplásica , Estudos Prospectivos , Estudos RetrospectivosRESUMO
BACKGROUND: Our previous phase-3 study (TTCC 2503) failed to show overall survival advantage of 2 induction chemotherapy (IC) regimens followed by standard concurrent chemoradiotherapy (CRT) over CRT alone in patients with unresectable locally advanced head and neck squamous-cell carcinoma (LAHNSCC). This study described the long-term survival of those patients. MATERIALS AND METHODS: Long-term follow-up study of patients with untreated LAHNSCC assigned to IC (three cycles), with either docetaxel, cisplatin and 5-fluorouracil (TPF arm) or cisplatin and 5-fluorouracil (PF arm), followed by CRT, or CRT alone, included in the previous TTCC 2503 trial. RESULTS: In the intention-to-treat population (n = 439), the median OS times were 25.4 (95% CI, 16.8-34.4), 26.2 (95% CI, 18.2-36.6) and 25.4 months (95% CI, 17.4-36.0) in the TPF-CRT, PF-CRT and CRT arms, respectively (log-rank p = 0.51). In the per-protocol population (n = 355), patients with larynx-hypopharynx primary tumors treated with IC (TPF or PF) followed by CRT had a longer median PFS than those who received CRT alone. Moreover, patients with ECOG 0 treated with IC (TPF or PF) followed by CRT had a better TTF than those with CRT alone. There were no statistically significant differences in terms of OS, PFS or TTF, according to the tumor load or affected nodes. CONCLUSION: After a long follow-up, the TTCC 2503 trial failed to show the benefit of IC-CRT in unresectable LAHNSCC regarding the primary end point. However, fit patients with ECOG 0 and primary larynx-hypopharyngeal tumors may benefit from the use of IC if administered by an experienced team. ClinicalTrials.gov identifier NCT00261703.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia , Neoplasias de Cabeça e Pescoço/mortalidade , Quimioterapia de Indução , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Cisplatino/uso terapêutico , Ensaios Clínicos Fase III como Assunto , Intervalos de Confiança , Docetaxel/uso terapêutico , Fluoruracila/uso terapêutico , Seguimentos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Neoplasias Hipofaríngeas/tratamento farmacológico , Neoplasias Hipofaríngeas/mortalidade , Neoplasias Hipofaríngeas/patologia , Neoplasias Hipofaríngeas/terapia , Análise de Intenção de Tratamento , Neoplasias Laríngeas/tratamento farmacológico , Neoplasias Laríngeas/mortalidade , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/terapia , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Neoplasias Bucais/terapia , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia , Taxoides/uso terapêutico , Resultado do Tratamento , Carga TumoralRESUMO
Muscle-invasive bladder cancer is an aggressive disease with at least 50% of patients dying from metastases within 2 years of diagnosis. The 5-year survival rate for metastatic bladder cancer is <15%. Although modern combination chemotherapy regimens have improved median survival from 6 to 14 months compared with best supportive care, there is still a great opportunity for improvement. New therapies and strategies for better patient and treatment selection are now being investigated for advanced bladder cancer. These include agents that target several pathways involved in the pathogenesis of the disease--such as growth factor receptors, angiogenic pathways, p53, cell cycle checkpoints and apoptosis--as well as novel chemotherapeutic agents. Results from recent and ongoing trials suggest that some of these agents could soon emerge as useful players to overcome the limitations of our present therapies.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Drogas em Investigação/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Carcinoma/metabolismo , Drogas em Investigação/administração & dosagem , Humanos , Receptores de Fatores de Crescimento/antagonistas & inibidores , Receptores de Fatores de Crescimento/metabolismo , Transdução de Sinais/fisiologia , Neoplasias da Bexiga Urinária/metabolismoRESUMO
A stable and sensitive biosensor for phenol detection based on a screen printed electrode modified with tyrosinase, multiwall carbon nanotubes and glutaraldehyde is designed and applied in a flow injection analytical system. The proposed carbon nanotube matrix is easy to prepare and ensures a very good entrapment environment for the enzyme, being simpler and cheaper than other reported strategies. In addition, the proposed matrix allows for a very fast operation of the enzyme, that leads to a response time of 15 s. Several parameters such as the working potential, pH of the measuring solution, biosensor response time, detection limit, linear range of response and sensitivity are studied. The obtained detection limit for phenol was 0.14 x 10(-6) M. The biosensor keeps its activity during continuous FIA measurements at room temperature, showing a stable response (RSD 5%) within a two week working period at room temperature. The developed biosensor is being applied for phenol detection in seawater samples and seems to be a promising alternative for automatic control of seawater contamination. The developed detection system can be extended to other enzyme biosensors with interest for several other applications.
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Técnicas Biossensoriais/métodos , Eletroquímica/métodos , Nanotubos de Carbono/química , Fenol/análise , Água do Mar/análise , Poluentes da Água/análise , Agaricales/enzimologia , Eletrodos , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Limite de Detecção , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/metabolismo , Nanotubos de Carbono/ultraestruturaRESUMO
The incidence of human papillomavirus (HPV)-related oropharyngeal cancer is increasing in some regions. Nevertheless, the epidemiology of this disease has not been extensively investigated in southern Europe. We conducted a retrospective cohort study of patients diagnosed with primary oropharyngeal cancer from 1991 to 2016. Cancer tissues underwent histopathological evaluation, DNA quality control, HPV-DNA detection and p16INK4a immunohistochemistry. Data were collected from medical records. Factors associated with HPV positivity and time trends were evaluated with multivariable Bayesian models. The adjusted prevalence of HPV-related cases in 864 patients with a valid HPV-DNA result was 9.7%, with HPV-DNA/p16INK4a double positivity being considered. HPV-related oropharyngeal cancer was likely to occur in non-smokers and non-drinkers, to be located in the tonsil or diagnosed at advanced stages. Time-trend analysis showed an increasing risk of HPV-related oropharyngeal cancer in the most recent periods (5-year period increase of 30%). This increase was highest and with a clear increasing trend only in the most recent years (2012-2016). The prevalence of HPV-related oropharyngeal cancer started to sharply increase in the most recent years in our setting, as occurred two decades ago in areas where most oropharyngeal cancer cases are currently HPV-related. Our results provide a comprehensive assessment of the epidemiological landscape of HPV-related oropharyngeal cancer in a region of southern Europe.
Assuntos
Alphapapillomavirus , Neoplasias Orofaríngeas/epidemiologia , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Prevalência , Estudos RetrospectivosRESUMO
BACKGROUND: There are limited data about the role of endoscopic ultrasound-guided tissue acquisition (EUS-TA), by fine needle aspiration (EUS-FNA) or biopsy (EUS-FNB), in the evaluation of the adrenal glands (AG). The primary aim was to assess the diagnostic yield and safety. The secondary aims were the malignancy predictors, and to create a predictive model of malignancy. METHODS: This was a retrospective nationwide study involving all Spanish hospitals experienced in EUS-TA of AGs. Inclusion period was from April-2003 to April-2016. Inclusion criteria: all consecutive cases that underwent EUS-TA of AGs. EUS and cytopathology findings were evaluated. Statistical analyses: diagnostic accuracy of echoendoscopist's suspicion using cytology by EUS-TA, as gold standard; multivariate logistic regression model to predict tumor malignancy. RESULTS: A total of 204 EUS-TA of AGs were evaluated. Primary tumor locations were lung70%, others19%, and unknown11%. AG samples were adequate for cytological diagnosis in 91%, and confirmed malignancy in 60%. Diagnostic accuracy of the endosonographer's suspicion was 68%. The most common technique was: a 22-G (65%) and cytological needle (75%) with suction-syringe (66%). No serious adverse events were described. The variables most associated with malignancy were size>30mm (OR2.27; 95%CI, 1.16-4.05), heterogeneous echo-pattern (OR2.11; 95%CI, 1.1-3.9), variegated AG shape (OR2.46; 95%CI, 1-6.24), and endosonographer suspicion (OR17.46; 95%CI, 6.2-58.5). The best variables for a predictive multivariate logistic model of malignancy were age, sex, echo-pattern, and AG-shape. CONCLUSIONS: EUS-TA of the AGs is a safe, minimally invasive procedure, allowing an excellent diagnostic yield. These results suggest the possibility of developing a pre-EUS procedure predictive malignancy model.
Assuntos
Glândulas Suprarrenais/patologia , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Neoplasias das Glândulas Suprarrenais/patologia , Idoso , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/efeitos adversos , Feminino , Humanos , Masculino , Análise Multivariada , Estudos Retrospectivos , SegurançaRESUMO
PURPOSE: To assess the efficiency of pazopanib compared with trabectedin in the treatment of adult patients with selective subtypes of advanced soft-tissue sarcoma (STS) after chemotherapy failure. METHODS: The progression of STS was modeled using a partitioned survival analysis model. Survival curves for pazopanib and trabectedin were modeled using data from PALETTE phase III clinical trial and based on unadjusted indirect comparison. Effectiveness was measured in quality-adjusted life years (QALY). The Spanish National Health System perspective was considered over a 10-year time horizon, including direct health care costs (
Assuntos
Antineoplásicos/economia , Antineoplásicos/uso terapêutico , Pirimidinas/economia , Pirimidinas/uso terapêutico , Sarcoma/tratamento farmacológico , Sulfonamidas/economia , Sulfonamidas/uso terapêutico , Ensaios Clínicos Fase III como Assunto , Análise Custo-Benefício , Dioxóis/economia , Dioxóis/uso terapêutico , Progressão da Doença , Custos de Medicamentos , Humanos , Indazóis , Probabilidade , Anos de Vida Ajustados por Qualidade de Vida , Sarcoma/economia , Espanha , Tetra-Hidroisoquinolinas/economia , Tetra-Hidroisoquinolinas/uso terapêutico , Trabectedina , Resultado do TratamentoRESUMO
Vascular prostacyclin (PGI2) production is different in the arteries and veins of the dog. Experiments were performed to determine whether chronic grafting of the femoral vein into the arterial circulation would alter the normal PGI2 and thromboxane (TxA2) synthesis of the "arterialized" veins. Spontaneous and arachidonic acid (AA) stimulated PGI2 and TxA2 production (measured by radioimmunoassay of 6-keto PGF1 alpha and TxB2 respectively) were analysed in full thickness punch biopsies of the middle part of the grafts after 3 and 16 months and compared with unoperated veins and arteries. PGI2 production was significantly higher in arteries than in veins but no significant difference in TxB2 production was found. Middle "arterialized" venous graft produced significantly lower amounts of PGI2 and higher amounts of TxB2 than unoperated vessels. PGI2 production was more reduced in the distal than in the middle or the proximal parts of the venous grafts especially when stimulated with AA. These findings do not support the concept that the venous graft was biochemically adapted or "arterialized" in terms of PGI2 production when implanted for 3 months or longer. Rather, the markedly decreased PGI2/TxB2 ratio in the middle of the graft may be a contributory cause of thrombogenicity and may be implicated in the pathogenesis of neointimal hyperplasia.
Assuntos
Veia Femoral/transplante , Tromboxano A2/biossíntese , Tromboxano B2/biossíntese , Grau de Desobstrução Vascular , Animais , Ácidos Araquidônicos/farmacologia , Artérias/cirurgia , Autopsia , Cães , Epoprostenol/biossíntese , Hemodinâmica , MasculinoRESUMO
We determined the participation of the cellular compartment in the changes of plasma amino acid concentrations during maximal exercise test on a cycle ergometer. Following an overnight fast, male athletes were submitted to a maximal exercise test until fatigue (for 25 min approximately) to determine maximal oxygen uptake. The amino acid concentrations in total blood, plasma, and blood cells were determined before and after the maximal exercise test. Most essential amino acids were decreased significantly in the total blood concentration as a result of the maximal exercise test. However, the concentrations of most nonessential amino acids tended to be significantly increased. Amino acid concentration was increased most in plasma. Concentrations of blood cell alanine and proline were significantly increased by 26% and 15%, respectively, after the maximal exercise test. No significant differences in blood cell concentrations of other amino acids induced by the exercise test were found, although the amount of tryptophan in blood cells was increased after exhaustive exercise.
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One hundred and fifty male Sprague-Dawley rats were divided into six groups: control, antrectomy, truncal vagotomy with pyloroplasty, intestinal resection, antrectomy with intestinal resection, and truncal vagotomy with pyloroplasty and intestinal resection. In the control group gastric acid secretion and plasma levels of gastrin were calculated. In the other five groups the same calculations were made 3 months after the corresponding operations. In all animals samples of the gastric wall were taken after specific dyeing of the parietal cells of these samples. In all samples prepared in this way, the variables of parietal cell volume per unit of muscularis mucosa were obtained by a morphometric method. The statistical survey using the levels of gastric acidity, gastrinemia, and parietal volumes of the six groups of animals showed that there is no relation between gastrinemia and gastric acid secretion, nor between gastrinemia and parietal volume, but that there is a significant correlation between gastric acid secretion and parietal volume. Those results suggest that the parietal cell volume in the rat decreases when the secreting capacity of the mucosa is decreased, and that the plasma levels of gastrin do not have a direct trophic effect on the parietal cells of gastric mucosa.
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Ácido Gástrico/metabolismo , Gastrinas/sangue , Intestino Delgado/cirurgia , Animais , Intestino Delgado/citologia , Masculino , Piloro/cirurgia , Ratos , Ratos Endogâmicos , VagotomiaRESUMO
The A, B, O (H) blood group antigens (BGA) are glycolipids present in the plasma membranes of many different epithelial cells. Alterations in BGA expression have been described in malignant tumors and premalignant lesions. We have studied ABO (H) BGA expression in paraffin sections of gastric specimens using immunofluorescence techniques with monoclonal antibodies. 102 patients were studied. 15 with normal mucosa (NM); 16 with duodenal ulcer (DU); 23 with gastric ulcer (GU); 11 with pernicious anaemia (PA) and 37 with adenocarcinoma (AC). The expression of BGA in normal gastric mucosa is detected in surface epithelium, mucoid cell neck glands and parietal cells as well as 2/3 of antral glands. BGA expression in DU gastritis is very similar to that seen in NM. In atrophic chronic gastritis associated with GU and PA there is a significant decrease in BGA expression. In patients with PA, BGA expression is greater in antral mucosa than in fundic mucosa. Loss of BGA expression is more pronounced in atrophic chronic gastritis surrounding AC. Intestinal metaplasia shows variable BGA expression. Our results support the hypothesis that loss of BGA expression by epithelial gastric mucosal cells may be related to alterations in cellular differentiation and premalignant potential.
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Sistema ABO de Grupos Sanguíneos/imunologia , Mucosa Gástrica/imunologia , Anemia Perniciosa/imunologia , Anticorpos Monoclonais , Antígenos de Grupos Sanguíneos/imunologia , Carcinoma/imunologia , Úlcera Duodenal/imunologia , Imunofluorescência , Gastrite/imunologia , Humanos , Lesões Pré-Cancerosas/imunologia , Neoplasias Gástricas/imunologia , Úlcera Gástrica/imunologiaRESUMO
A case of hepatoid gastric adenocarcinoma is reported. The tumor had the histological and immunohistochemical features of both liver cell carcinoma and conventional intestinal-type adenocarcinoma. We discuss the main clinical and pathological features of this uncommon variety of gastric cancer.
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Adenocarcinoma/patologia , Neoplasias Gástricas/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/ultraestrutura , Carcinoma Hepatocelular , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Hepáticas , Pessoa de Meia-Idade , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/ultraestruturaRESUMO
INTRODUCTION AND OBJECTIVES: Measurement of valvular annular area is necessary for valvular flow volumen quantification by Doppler echocardiography. The aim of this work was to compare normal valvular annular area values obtained in a necropsic and an echocardiographic series and to ascertain whether a relationship exists between these areas and several anthropometric variables. METHODS: Necropsic series: valvular annular area was measured in 20 hearts from deceased patients (age range: 9-79 years; mean 52 +/- 18) without cardiovascular disease. Echocardiographic series: Valvular annular area was determined in 156 patients (age range: 6-86 years; mean 37 +/- 20) without cardiovascular disease. RESULTS: Necropsic series: multiple regression analysis showed valvular annular area values to be related mainly to height (p < 0.001) but also to weight (p < 0.01). Correlations between valvular annular area and body surface were low (r = 0.64-0.75). Aortic annular area index was slightly lower than the pulmonary annular area index and half that of the mitral annular area index (2.2 +/- 0.4, 2.5 +/- 0.5 and 4.4 +/- 0.8 cm2/m2, respectively). Tricuspid annular area index was the largest (6.7 +/- 1.0 cm2/m2). ECHOCARDIOGRAPHIC SERIES: Multiple regression analysis also showed a relationship between valvular annular area and height (p < 0.00001) and weight (p < 0.004). Correlations between valvular annular real values and body surface were poor (r = 0.45-0.71). Mean values of aortic, pulmonary and mitral valvular annular area indices were similar to those obtained in the necropsic series (2.1 +/- 0.2, 2.1 +/- 0.3, 4.1 +/- 0.6 cm2/m2, respectively). However, the tricuspid annular area index was clearly lower (4.5 +/- 0.6 cm2/m2, p < 0.001). CONCLUSIONS: Valvular annular area is influenced mainly by height, but also by weight. The correlation between these values and body surface is poor. Aortic annular area is similar to the pulmonary annular area and half that of the mitral annulus. Normal values determined by echocardiography and necropsy are similar, although tricuspid annular area by apical view is smaller than that obtained in the necropsic series.
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Valvas Cardíacas/anatomia & histologia , Valvas Cardíacas/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria , Autopsia , Criança , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de ReferênciaRESUMO
BACKGROUND: The presence of the 5569A polymorphism may lead to misdiagnosis of patients susceptible of hereditary hemochromatosis (HH). For that reason, samples containing the Cys282Tyr mutation were revised and the frequency of this polymorphism in our environment was assessed. PATIENTS AND METHOD: Twenty samples were retested and 56 controls were included. The study was performed by PCR-RFLP. RESULTS: The diagnosis was confirmed in 8 cases susceptible of error. However, an amplification deficiency of normal alleles was detected in 2 heterozygous (17%). The allelic frequency of the 5569A polymorphism in the control population was 14.3%. CONCLUSIONS: Although misdiagnosis was not committed, we recommend changing to any primer that does not include the 5569G/A polymorphism in the study of HH.
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Hemocromatose/diagnóstico , Íntrons/genética , Polimorfismo Genético/genética , RNA de Transferência de Cisteína/genética , Adulto , Análise Mutacional de DNA , Feminino , Expressão Gênica , Frequência do Gene/genética , Testes Genéticos , Antígenos HLA/genética , Hemocromatose/epidemiologia , Humanos , Masculino , Mutação Puntual/genética , Espanha/epidemiologiaRESUMO
Carcinomas with lymphoid stroma have been described in different locations: breast, uterine cervix, nasopharynx, esophagus and stomach. These neoplasms have a better prognosis probably due to the lymphoid reaction that takes place in the tumoral stroma. For this reason many authors prefer to consider this entity separate from the rest of gastric carcinomas. We present a case of gastric carcinoma with lymphoid stroma and neuroendocrine features. Such association has not been previously described in the Spanish literature.
Assuntos
Adenocarcinoma Mucinoso/patologia , Neoplasias Gástricas/patologia , Adenocarcinoma Mucinoso/metabolismo , Idoso , Mucosa Gástrica/metabolismo , Histocitoquímica , Humanos , Imuno-Histoquímica , Masculino , Estômago/patologia , Neoplasias Gástricas/metabolismoRESUMO
The following article discusses the experimental and clinical reasons for using absorbable synthetic explants in retinal surgery. We have carried out experimental studies with absorbable synthetic explants bandmade from absorbable sewing threads: PG910, PGA and PDS; proving that these explants are well tolerated by the organism. Their reabsorption time is from 45 days using PG910, to 8 months using PDS; these periods are sufficient for proper anatomical healing of the retina to take place. We present 13 cases of extraction of Teflon explants after retinal detachment surgery; in none of these cases did re-detachment of the retina occur. Consequently, this induced us to introduce absorbable synthetic explants into retinal detachment surgery, using absorbable threads, having previously carried out an experimental study on rabbits. We present 10 cases of retinal detachment operated on with PDS from 95 cases operated on using absorbable synthetic explants; 100% anatomical healing of the retina was achieved. We consider this type of explant to be the ideal material for retinal detachment healing, due to the fact that its period reabsorption, being longer than those of the other explants, allows a longer indentation period.
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Poliésteres , Descolamento Retiniano/cirurgia , Absorção , Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polidioxanona , CoelhosRESUMO
Two cases of Disseminated Poroqueratosis of Mibelli with squamous cell carcinomata development of many lesions are reported. Histopathological findings showed us the typical structure of the cornoid limella. Ultrastructural features are described with increased number of Langerhans" cells. Treatment in both cases was RO-109359. Squamous cell carcinomata were treated by surgical excision.
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Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica/patologia , Ceratose/patologia , Neoplasias Cutâneas/patologia , Idoso , Carcinoma de Células Escamosas/ultraestrutura , Transformação Celular Neoplásica/ultraestrutura , Etretinato/uso terapêutico , Humanos , Ceratose/tratamento farmacológico , Células de Langerhans/ultraestrutura , Masculino , Pessoa de Meia-Idade , Neoplasias Cutâneas/ultraestruturaRESUMO
A novel enzyme entrapment approach based on an electropolymerization process utilizing multi-walled carbon nanotubes (MWCNT), ß-cyclodextrin (ß-CD) and glucose oxidase (GOx) is shown. Dopamine (DA) quantification is presented using a screen-printed electrode modified by electropolymerization of cyclodextrin with glucose oxidase, SPE/MWCNT/ß-CD-GOx. In order to show the relevance of the enzyme entrapment strategy controlled by electropolymerization to develop a specific and efficient biosensor, the various parts composing the electrode: SPE, SPE/ß-CD, SPE/GOx, SPE/ß-CD/GOx, SPE/MWCNT/ß-CD, SPE/MWCNT/GOx and SPE/MWCNT/ß-CD/GOx were tested separately. It was shown that although DA determination can be achieved with all of them, the electrodes modified with MWCNT presented better analytical features that those built without MWCNT, the best being the one including all components. This biosensor displayed good reproducibility, repeatability, and prolonged life-time under cold storage conditions. Its DA limit of detection (LOD) was 0.48±0.02 µA in a linear range of 10-50 µM with a sensitivity of 0.0302±0.0003 µA µM(-1) that makes it comparable or even better than many other electrodes reported in the literature. Moreover, it was also shown that using this electrode, DA quantification can be done in the presence of interfering agents such as ascorbic and uric acid. These findings demonstrate that the approach employed is feasible for enzyme entrapment and may find applications in other biosensing systems, where better sensitivity, stability and fast response are required.