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1.
Magn Reson Chem ; 58(9): 902-912, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32526806

RESUMO

Cellulose-based artefacts are highly prone to degradation, especially in the presence of acidic compounds, which trigger the depolymerization of cellulose chains and lead to a loss in the original mechanical resistance of the material. Calcium hydroxide nanoparticles dispersed in organic solvent have been recently proposed for the deacidification of cellulose-based artworks. In this work, changes induced on paper by a deacidification treatment, following an acidification bath, were studied by nuclear magnetic resonance (NMR) relaxometry and by the so-called NMR diffraction of water trapped in the cellulose network. The deacidification treatment modifies intrachain and interchain bonds in hydrolyzed and degraded cellulose, leading to a buffered cellulose network configuration, which is similar to that characterizing the untreated reference sample in terms of relaxation parameters. Overall, calcium hydroxide nanoparticles are demonstrated effective in hindering the degradation of cellulose induced by acids and ageing in strong environmental conditions, even from the standpoint of cellulose network arrangement. It is worth noting, too, that the unilateral NMR device used for the relaxation measurements may represent a powerful tool for the preservation of cellulose-based artworks because it allows for the monitoring of the conservation status of cellulose in a completely non-invasive manner.

3.
Childs Nerv Syst ; 33(11): 1969-1976, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28770391

RESUMO

PURPOSE: An intensive therapeutic strategy for metastatic medulloblastoma was launched in 1998 in our Institution. The aim of this study was to examine the long-term quality of life (QoL) in survivor patients at least 3 years after the end of the treatment. METHODS: Patients were asked to complete self-administered QoL questionnaires. An index of physical impairment (IPI) was scored (range 0-100; the lower the score the better) based on clinical objective observations. Patients were divided into two groups (lower IPI group, and higher IPI group) and descriptively compared accordingly. RESULTS: The study was completed by 25/33 eligible patients. Despite patients with a higher IPI reported worse perceived health condition, they had better emotional and psychological scores than those with a lower IPI in all QoL questionnaires. CONCLUSION: In our sample, patients with more severe objective and perceived physical impairments reported a better psychosocial QoL, possibly because the greater attention paid to them by society and family contributes to a better adjustment in long-term survivors. On this base, it should be recommended that all survivors receive a strong support as the most impaired patients.


Assuntos
Neoplasias Cerebelares/radioterapia , Meduloblastoma/radioterapia , Radioterapia/efeitos adversos , Sobreviventes/psicologia , Adolescente , Criança , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Qualidade de Vida , Radioterapia/métodos , Inquéritos e Questionários
4.
Nat Nanotechnol ; 16(9): 1004-1010, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34211165

RESUMO

Modern and contemporary art materials are generally prone to irreversible colour changes upon exposure to light and oxidizing agents. Graphene can be produced in thin large sheets, blocks ultraviolet light, and is impermeable to oxygen, moisture and corrosive agents; therefore, it has the potential to be used as a transparent layer for the protection of art objects in museums, during storage and transportation. Here we show that a single-layer or multilayer graphene veil, produced by chemical vapour deposition, can be deposited over artworks to protect them efficiently against colour fading, with a protection factor of up to 70%. We also show that this process is reversible since the graphene protective layer can be removed using a soft rubber eraser without causing any damage to the artwork. We have also explored a complementary contactless graphene-based route for colour protection that is based on the deposition of graphene on picture framing glass for use when the direct application of graphene is not feasible due to surface roughness or artwork fragility. Overall, the present results are a proof of concept of the potential use of graphene as an effective and removable protective advanced material to prevent colour fading in artworks.

5.
J Colloid Interface Sci ; 576: 147-157, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32416547

RESUMO

HYPOTHESIS: Strongly degraded cellulosic artworks usually need deacidification and consolidation. Alkaline nanoparticles are known to be effective in neutralizing the acidity, while cellulose nanocrystals have the potential to be used as compatible and effective strengthening agents. EXPERIMENTS: We have grafted cellulose nanocrystals with oleic acid using a 1'1-carbonyldiimidazole-mediated procedure, to increase their dispersibility in organic solvents, and synthesized Ca(OH)2 or CaCO3 nanoparticles via a solvothermal process. Grafted nanocellulose and alkaline nanoparticles were used to prepare ethanol-based "hybrids". Prior to the application, the physico-chemical properties of nanocellulose dispersions and "hybrids" were studied by rheology and small-angle X-ray scattering. FINDINGS: Cellulose nanocrystals were effectively grafted and stably dispersed in ethanol. It was shown that the use of ethanol as a dispersing medium, and the addition of alkaline nanoparticles act in a synergistic way, increasing the interactions between grafted cellulose nanocrystals, leading to the formation of clusters. These dispersions are thixotropic, a behavior particularly appealing to conservation purposes, since they can be applied in the liquid state, or, when a more confined application is required, they can be applied in a gel-like state. As a result of the application, an improvement in the mechanical properties of paper and an increase of pH were obtained.

6.
J Colloid Interface Sci ; 547: 370-381, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30974252

RESUMO

HYPOTHESIS: The reaction of Ca(OH)2 with CO2 to form CaCO3 (carbonation process) is of high interest for construction materials, environmental applications and art preservation. Here, the "Boundary Nucleation and Growth" model (BNGM) was adopted for the first time to consider the effect of the surface area of Ca(OH)2 nanoparticles on the carbonation kinetics. EXPERIMENTS: The carbonation of commercial and laboratory-prepared particles' dispersions was monitored by Fourier Transform Infrared Spectroscopy, and the BNGM was used to analyze the data. The contributions of nucleation and growth of CaCO3 were evaluated separately. FINDINGS: During carbonation the boundary regions of the Ca(OH)2 particles are densely populated with CaCO3 nuclei, and transform early with subsequent thickening of slab-like regions centered on the original boundaries. A BNGM limiting case equation was thus used to fit the kinetics, where the transformation rate decreases exponentially with time. The carbonation rate constants, activation energies, and linear growth rate were calculated. Particles with larger size and lower surface area show a decrease of the rate at which the non-nucleated grains between the boundaries transform, and an increase of the ending time of Ca(OH)2 transformation. The effect of temperature on the carbonation kinetics and on the CaCO3 polymorphs formation was evaluated.

7.
Eur J Paediatr Neurol ; 23(4): 560-570, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31182404

RESUMO

It is increasingly accepted that survival alone is an inadequate measure of the success of childhood brain tumour treatments. Consequently, there is growing emphasis on capturing quality of survival. Ependymomas are the third most frequently occurring brain tumours in childhood and present significant clinical challenges. European Society of Paediatric Oncology Ependymoma II is a comprehensive international program aiming to evaluate outcomes under different treatment regimens and improve diagnostic accuracy. Importantly, there has been agreement to lower the age at which children with posterior fossa ependymoma undergo focal irradiation from three years to either eighteen months or one year of age. Hitherto radiotherapy in Europe had been reserved for children over three years due to concerns over adverse cognitive outcomes following irradiation of the developing brain. There is therefore a duty of care to include longitudinal cognitive follow-up and this has been agreed as an essential trial outcome. Discussions between representatives of 18 participating European countries over 10 years have yielded European consensus for an internationally accepted test battery for follow-up of childhood ependymoma survivors. The 'Core-Plus' model incorporates a two-tier approach to assessment by specifying core tests to establish a minimum dataset where resources are limited, whilst maintaining scope for comprehensive assessment where feasible. The challenges leading to the development of the Core-Plus model are presented alongside learning from the initial stages of the trial. We propose that this model could provide a solution for future international trials addressing both childhood brain tumours and other conditions associated with cognitive morbidity.


Assuntos
Assistência ao Convalescente/métodos , Neoplasias Encefálicas/radioterapia , Ensaios Clínicos como Assunto/métodos , Cognição/efeitos da radiação , Ependimoma/radioterapia , Adolescente , Sobreviventes de Câncer/psicologia , Criança , Pré-Escolar , Irradiação Craniana/efeitos adversos , Europa (Continente) , Feminino , Humanos , Lactente , Masculino , Morbidade
8.
Int J Immunopathol Pharmacol ; 20(4): 827-31, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18179755

RESUMO

Mother-child human leukocyte antigen (HLA)diversity is protective for vertical transmission of some viruses. The aim of this study is to evaluate the role of mother-child HLA diversity on hepatitis C virus (HCV) vertical transmission. Forty consecutive HCV infected and 46 consecutive control uninfected children born to HCV-RNA positive mothers were evaluated for HLA class-1 type concordance with their mothers. No significant difference in the degree of HLA concordance was found between HCV infected and uninfected children both when A, B, C (p=0.30) and when only A and B alleles were evaluated (p=0.59). Mother-infant HLA concordance does not affect HCV vertical transmission.


Assuntos
Antígenos HLA/genética , Hepacivirus , Hepatite C Crônica/transmissão , Transmissão Vertical de Doenças Infecciosas , Adulto , Alelos , Variação Antigênica/genética , Feminino , Hepatite C Crônica/congênito , Hepatite C Crônica/virologia , Teste de Histocompatibilidade , Humanos , Recém-Nascido , Gravidez , RNA/biossíntese , RNA/genética
9.
Minerva Pediatr ; 67(3): 209-17, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25297322

RESUMO

AIM: Sleep is essential for children's physical and mental recovery and it is indispensable for their growth, for endocrine and for immune function, and for the development of cognitive behavioral skills. The purpose of this study is to describe the impact of hospitalization on the sleep patterns of newborns, infants and toddlers, as well as mothers' perceptions of any changes in their children's sleep patterns. METHODS: This was a single-centre cross-sectional study. The study included children aged up to 2 years who had been hospitalized for more than two days, selected by accidental sampling. Data were collected using an anonymous questionnaire with open and closed questions administered to mothers. RESULTS: Two hundred and one children aged on average 11.2 months (SD 10.3) were enrolled in the study. The percentage of children who at home used to sleep less than 5 hours a night increased by 4.7% in hospital, while the percentage of children sleeping 9 to 11 hours at home decreased by 5.9% in hospital. In hospital mothers put their children to bed later than at home. Indeed, the number of individuals going to bed between 9 and 10 p.m. decreased by 9.8% in hospital, while the number of children going to bed between 10 and 11 p.m. increased by 10.1%. The number of children who had 2 to 4 awakenings per night increased by 13.9% and the number of those who had 4 to 6 nocturnal awakenings increased by 4.8%; 50.5% of mothers reported that their children's sleep was interrupted by nurses to provide care. Mothers generally perceived their children's sleep as adequate, even if they noticed that their children were more restless and irritable. Mothers with only one child reported that they had more difficulty helping their children fall asleep (P=0.02). CONCLUSION: The study highlights the need to review the routine in paediatric wards on the basis of the sleep needs of children. Further studies are needed to estimate the effectiveness of the specific measures suggested by mothers.


Assuntos
Hospitalização , Transtornos do Sono-Vigília/epidemiologia , Sono/fisiologia , Estudos Transversais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Inquéritos e Questionários
10.
Eur J Hum Genet ; 8(8): 597-603, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10951522

RESUMO

We studied the case of a subject with an inverted duplication of 40 cM of 2q33-q37 concurrent with a 10 cM deletion of the distal 2q, the latter not being detectable by cytogenetics. Microsatellite analysis demonstrated the absence of maternal alleles in the deleted region and a double dosage for one of the maternal alleles in the duplication region. We hypothesised that this type of rearrangement occurs at meiosis I, while the two homologues are synapsed for most of their length. The presence of inverted duplicons in the same chromosome arm would favour the partial refolding of one homologue into itself so leading to the intrachromatid synapsis and recombination of the inverted repeats. The arising recombinant chromosome is deleted for the region beyond the most distal repeat and with the chromatids joined together at the level of the region located between the two duplicons. At meiosis II, the two linked chromatids can join the opposite poles provided that a breakage between the two centromeres occurs leading to a duplicated/deleted chromosome and a simply deleted chromosome. This model can be extended to all the so-called inverted duplication cases and to part of the terminal deletions. In fact the finding that, in our invdup(2q), the entire 40 cM duplication region involves only one of the two maternal alleles, indeed indicates that the abnormal crossover occurs between sister chromatids. The phenotype associated with our 2q rearrangement led us to narrow the critical region for the Albright-like syndrome to 10 cM in the subterminal 2q region.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 2/genética , Duplicação Gênica , Rearranjo Gênico/genética , Criança , Bandeamento Cromossômico , Quebra Cromossômica , DNA/análise , Feminino , Displasia Fibrosa Poliostótica/genética , Transtornos do Crescimento/genética , Humanos , Hibridização in Situ Fluorescente , Meiose/genética , Repetições de Microssatélites , Fenótipo , Recombinação Genética/genética
11.
Clin Nutr ; 19(2): 137-9, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10867733

RESUMO

We describe a case of methylmalonic aciduria (MMA) occurred in a 22-month-old boy whose diet was exclusively based upon breast-feeding from a mother following a long-lasting strict vegetarian diet. Clinical picture showed a dramatic onset, with a profound drowsiness associated with a severe metabolic acidosis, hyperammonemia, macrocytic anemia, ketonuria, and massive methylmalonic aciduria without homocystinuria. Both symptoms and biochemical findings quickly improved thanks to prompt vitamin B(12)parenteral therapy. Biochemical and enzymatic findings allowed a diagnosis of mild mutase deficiency, which only and inadequate dietary B(12)contribution might have revealed. Our case highlights the risk of a prolonged strictly vegetarian diet of lactating mother for providing inadequate amounts of some nutrients to the breast-fed baby. Moreover, such a dietary behaviour could dramatically unmask otherwise clinically unapparent metabolic defects in the baby.


Assuntos
Aleitamento Materno/efeitos adversos , Dieta Vegetariana , Transferases Intramoleculares/deficiência , Ácido Metilmalônico/urina , Adulto , Feminino , Humanos , Lactente , Masculino , Fatores de Tempo
12.
Anticancer Res ; 15(2): 495-501, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7763029

RESUMO

As valid therapeutic alternatives to adriamycin, with a more favourable safety profile, epirubicin (E) and novantrone (N) were compared in combination with fluorouracil (F) and cyclophosphamide (C) in a prospective randomized clinical trial as first-line treatment for metastatic breast cancer (mbc). 158 women with mbc were randomly allocated to receive FEC or FNC regimen; the dosage in mg/m2 was as follows: 500 for C and F, 75 for E and 10 for N. All drugs were administered iv. on day 1 and recycled on day 21. In 141 evaluable patients the response rate (CR+PR) was better in the FEC (43.6%) than in the FNC regimen (30.3%) (95% C.I. of 32% to 55% versus 14% to 34%), without any statistically significant difference. Differences in response rate were significantly in favour of FEC group in previously untreated patients (57.6% versus 25%, p = .02), and in postmenopausal women (46.1% versus 23.6%, p = .01). No significant differences between the two treatment arms were observed in terms of either time to progression or duration of response and survival. The most important dose-limiting toxicity was hematological (leuko-and thrombocytopenia were significantly higher in FNC-treated patients). This difference in hematological toxicity sustained a significantly different incidence of delays in administering chemotherapy courses, which precluded the administration of comparable doses of all drugs in both groups. The incidence of complete alopecia was significantly higher in FEC-treated patients, while no clinical or instrumental evidence of CHF was observed with either regimen. Due to its more favourable therapeutic profile, the E-containing regimen seems a suitable first-line treatment for previously untreated patients with mbc, while the FNC combination should be offered to women refusing hair loss.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Idoso , Alopecia/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Doenças da Medula Óssea/induzido quimicamente , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Progressão da Doença , Intervalo Livre de Doença , Epirubicina/administração & dosagem , Epirubicina/efeitos adversos , Feminino , Fluoruracila/administração & dosagem , Humanos , Tábuas de Vida , Menopausa , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Mitoxantrona/efeitos adversos , Metástase Neoplásica , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias Hormônio-Dependentes/patologia , Estudos Prospectivos , Indução de Remissão , Análise de Sobrevida , Resultado do Tratamento
13.
Anticancer Res ; 21(1B): 739-42, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11299836

RESUMO

BACKGROUND: The majority of patients with hepatocellular carcinoma (HCC) cannot undergo surgery because of multifocality, location or advanced cirrhosis. Our experience with percutaneous radiofrequency ablation for treatment of patients suffering from unresectable hepatocellular carcinoma is described here. PATIENTS AND METHODS: Fifteen patients (ten men and five women) with eighteen primary hepatocellular tumors underwent percutaneous radiofrequency ablation. The mean diameter of the HCCs was 32 mm (ranging from 15 mm to 62 mm). The patients were treated under ultrasound guidance using either a 18-gauge internally cooled electrode or a 14-gauge electrode with four expandable hooks. RESULTS: Complete necrosis was achieved in 15 lesions after one session of RF ablation. The persistence of a small portion of viable tissue was seen in two lesions. One lesion was not evaluable. After a mean follow-up period of 9.2 months (range 3-24 months), eleven patients (76%) showed no sign of local or distant recurrence, one patient developed a new lesion and one of two patients with persistence of viable tissue obtained a complete necrosis after the injection of percutaneous ethanol. Moreover, a major complication (intraperitoneal bleeding requiring surgical treatment) and three minor complications (1 pleuric effusion and 2 perihepatic fluid collections that resolved spontaneously) were observed. CONCLUSION: RF ablation is a simple, well-tolerated and effective procedure for the treatment of unresectable hepatocellular carcinomas.


Assuntos
Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/métodos , Neoplasias Hepáticas/cirurgia , Ultrassonografia de Intervenção , Idoso , Idoso de 80 Anos ou mais , Carcinoma Hepatocelular/complicações , Carcinoma Hepatocelular/diagnóstico por imagem , Ablação por Cateter/efeitos adversos , Ablação por Cateter/instrumentação , Feminino , Seguimentos , Hemoperitônio/etiologia , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Humanos , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/etiologia , Derrame Pleural/etiologia , Resultado do Tratamento , Ultrassonografia de Intervenção/instrumentação
14.
Anticancer Res ; 15(1): 25-8, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7537486

RESUMO

Hematopoietic growth factors (HGFs) are glycoproteins that control hemopoiesis. They have potential usefulness in a range of clinical conditions including the treatment of patients with myelosuppression induced by chemotherapy. Among HGFs, Stem Cell Factor (SCF) and Interleukin 6 (IL-6) are attracting interest for their capacity to stimulate early hematopoietic progenitors. Furthermore, their use in combination with late-acting growth factors with a more lineage-restricted potential (such as granulocyte colony-stimulating factor, G-CSF) might be expected to offer optimal marrow stimulation and usefulness in clinical oncology. Since non-hematopoietic malignant cells may express receptors for HGFs and respond to these peptides in vitro, we investigated clonal growth 3H-thymidine incorporation and cell cycle analysis by flow cytometry of 5 human solid tumor cell lines under the influence of SCF and IL-6 with or without G-CSF. Our experiments show that these cytokines have no effects on the proliferative capacity of the cell lines tested. Based on our and previously reported data, the use of these HGFs can be considered safe in cancer patients.


Assuntos
Divisão Celular/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/farmacologia , Fatores de Crescimento de Células Hematopoéticas/farmacologia , Interleucina-6/farmacologia , Moléculas de Adesão Celular/farmacologia , Linhagem Celular , DNA de Neoplasias/análise , DNA de Neoplasias/biossíntese , Interações Medicamentosas , Citometria de Fluxo , Humanos , Neoplasias , Proteínas Recombinantes/farmacologia , Fator de Células-Tronco , Timidina/metabolismo , Células Tumorais Cultivadas , Ensaio Tumoral de Célula-Tronco
15.
Anticancer Res ; 18(6B): 4705-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9891544

RESUMO

BACKGROUND: We evaluated the infusion-related toxicity of cryopreserved autologous circulating progenitor cells transplanted in 22 patients receiving high dose chemotherapy and stem cells transplantation for malignancy. MATERIALS AND METHODS: Progenitor cells were collected following mobilization with chemotherapy plus filgrastim and stored in liquid nitrogen in the presence of 10% dimethylsulfoxide (DMSO). Before infusion of the graft, patients were medicated with mannitol, hydrocortisone and clorphenamine. The amount of DMSO infused as well as the number of dead and damaged cells were evaluated as possible cause of toxicity. RESULTS: Eleven patients (50%) experienced symptoms related to graft infusion, nausea and vomiting being the most common adverse events. Hypotension was documented in 3 patients (one of them developing transient bradycardia resolved with atropin administration) and one had hypertension with tachycardia. Other observed side effects were: chest tightness (2 pts), fever and chills (3 pts), associated with abdominal cramps (2 pts). 7 out of 8 (88%) patients infused with greater than 30 mL volume of DMSO experienced side-effects, the grade of toxicity being significantly less in those receiving lower amount (< 30 mL) of DMSO. Two out of 4 pts who received the highest number of dead cells (> 10 x 10(9)) developed toxicity. CONCLUSIONS: In our experience the infusion of cryopreserved peripheral blood progenitors caused minor to moderate toxicity in most cases and, when present, side effects were observed only during infusion. The amount of DMSO present in the graft is related to the grade of toxicity.


Assuntos
Criopreservação , Crioprotetores/efeitos adversos , Dimetil Sulfóxido/efeitos adversos , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neoplasias/terapia , Adulto , Antineoplásicos/uso terapêutico , Neoplasias da Mama/terapia , Sobrevivência Celular , Criopreservação/métodos , Feminino , Filgrastim , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Humanos , Hipertensão , Linfoma não Hodgkin/terapia , Masculino , Pessoa de Meia-Idade , Náusea , Proteínas Recombinantes , Transplante Autólogo , Vômito
16.
Eur J Gastroenterol Hepatol ; 9(1): 67-9, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9031902

RESUMO

OBJECTIVE: To evaluate the relationship between hepatitis C virus (HCV)-RNA levels and genotypes in order to establish their potentially predictive role in interferon (IFN) response. DESIGN: To detect HCV genotype at baseline and HCV viraemia levels before and during IFN treatment in three groups of patients with different IFN response. METHODS: Our study included 85 patients with biopsy-proven chronic hepatitis C who underwent IFN therapy at standard schedule (3 MU thrice weekly for 6 months). On the basis of IFN response they were subdivided into three groups as follows: non responders (NR: 27 cases) when alanine aminotransferase (ALT) values (normal value: 0-40 IU) at the end of treatment were abnormal (101.7 +/- 10.4); responders relapsing (RR: 29 cases) when normal ALT values at the end of therapy (28.14 +/- 1.7) increased during follow-up; sustained (long-term) responders (LTR: 29 cases) when ALT values remained normal for at least 12 months of follow-up (ALT values at the end of therapy: 21.8 +/- 1.4). ALT activity was monitored monthly during therapy and each month during 12 months of follow-up. HCV genotype was evaluated before starting treatment whereas HCV-RNA viraemia was checked at baseline and at the 1st and 6th months of therapy. RESULTS: The baseline viral load was higher in the NR group than in the RR and LTR groups independently of genotype; HCV-RNA levels progressively decreased during therapy independently of response but the levels remained significantly higher in the NR group. Genotype 1b was prevalent in the NR group. However, levels of viraemia in genotype 1b LTR patients are significantly lower than in genotype 1b NR patients. CONCLUSION: These results suggest that among viral-related parameters viraemia alone seems to play an important role in predicting response to IFN independently of genotype.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C/terapia , Interferon-alfa/uso terapêutico , RNA Viral/análise , Adulto , Idoso , Antivirais/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Seguimentos , Genótipo , Hepacivirus/patogenicidade , Hepatite C/etiologia , Humanos , Interferon-alfa/administração & dosagem , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Prevalência , Resultado do Tratamento , Viremia/etiologia , Viremia/terapia
17.
J Chemother ; 10(6): 492-5, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9876059

RESUMO

We have evaluated the combination of ifosfamide, carboplatin and etoposide (ICE regimen) along with mesna in 26 previously untreated patients with non small cell lung cancer (NSCLC). Thirteen stage III B and 13 stage IV patients received intermediate doses of ifosfamide (1000 mg/m2), carboplatin (120 mg/m2) and etoposide (120 mg/m2) given intravenously on day 1 to 3 every 4 weeks. Except for one patient who experienced grade 3 transient thrombocytopenia no major events of hematological or systemic toxicity were observed. Response rate (27%, 95% C.I., 10 to 44%), median duration of response (9 months, range 6-15), and survival (9.5 months, range 2-44+) were comparable to those achieved with conventional cisplatin-containing regimens. Our ICE combination, as compared to standard or high dose schedules appears effective, safe, well tolerated, and devoid of severe hematological toxicity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Adulto , Idoso , Carboplatina/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Etoposídeo/administração & dosagem , Feminino , Humanos , Ifosfamida/administração & dosagem , Neoplasias Pulmonares/patologia , Masculino , Mesna/administração & dosagem , Pessoa de Meia-Idade , Análise de Sobrevida , Resultado do Tratamento
18.
IEEE Trans Image Process ; 5(1): 49-55, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-18285089

RESUMO

Address-predictive vector quantization (APVQ) exploits the interblock dependency by jointly encoding the addresses of the codewords associated with spatially close blocks. It profiles the same image quality as memoryless VQ for a much lesser bit rate (BR) and the same computational complexity. In the generalized-cost-measure-based APVQ, the two steps of the encoding process, namely, VQ and predictive address encoding, are carried out jointly by minimizing a generalized cost measure, which takes into account both the BR and the distortion. Computer simulations show that a significant improvement can be obtained with respect to APVQ in terms of both BR and distortion. Compared with memoryless VQ, a bit-rate reduction of almost 60% is obtained for the same image quality.

19.
IEEE Trans Image Process ; 8(4): 476-89, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-18262892

RESUMO

This paper presents a new technique for the compression of multispectral images, which relies on the segmentation of the image into regions of approximately homogeneous land cover. The rationale behind this approach is that, within regions of the same land cover, the pixels have stationary statistics and are characterized by mostly linear dependency, contrary to what usually happens for unsegmented images. Therefore, by applying conventional transform coding techniques to homogeneous groups of pixels, the proposed algorithm is able to effectively exploit the statistical redundancy of the image, thereby improving the rate distortion performance. The proposed coding strategy consists of three main steps. First, each pixel is classified by vector quantizing its spectral response vector, so that both a reliable classification and a minimum distortion encoding of each vector are obtained. Then, the classification map is entropy encoded and sent as side information, Finally, the residual vectors are grouped according to their classes and undergo Karhunen-Loeve transforming in the spectral domain and discrete cosine transforming in the spatial domain. Numerical experiments on a six-band thematic mapper image show that the proposed technique outperforms the conventional transform coding technique by 1 to 2 dB at all rates of interest.

20.
IEEE Trans Image Process ; 4(6): 734-42, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-18290024

RESUMO

The authors use predictive pruned tree-structured vector quantization for the compression of medical images. Their goal is to obtain a high compression ratio without impairing the image quality, at least so far as diagnostic purposes are concerned. The authors use a priori knowledge of the class of images to be encoded to help them segment the images and thereby to reserve bits for diagnostically relevant areas. Moreover, the authors improve the quality of prediction and encoding in two additional ways: by increasing the memory of the predictor itself and by using ridge regression for prediction. The improved encoding scheme was tested via computer simulations on a set of mediastinal CT scans; results are compared with those obtained using a more conventional scheme proposed recently in the literature. There were remarkable improvements in both the prediction accuracy and the encoding quality, above and beyond what comes from the segmentation. Test images were encoded at 0.5 bit per pixel and less without any visible degradation for the diagnostically relevant region.

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