Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 108
Filtrar
1.
Anaerobe ; 69: 102366, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33862204

RESUMO

Gram-positive anaerobic cocci (GPAC) are responsible for 30% of anaerobic infections. Parvimonas micra is an emergent pathogen that is part of the oral and gastrointestinal commensal flora, and its role in several infection processes has recently emerged thanks to the improvement of diagnostic techniques. P. micra bacteraemia is reported in immunocompromised patients and is often complicated by abscesses. Here, we present a case study of multiple hepatic and brain abscesses caused by P. micra bacteraemia in a patient with complicated diverticulitis.


Assuntos
Antibacterianos/uso terapêutico , Abscesso Encefálico/etiologia , Firmicutes/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/complicações , Infecções por Bactérias Gram-Positivas/diagnóstico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Abscesso Hepático/etiologia , Idoso , Abscesso Encefálico/tratamento farmacológico , Feminino , Humanos , Abscesso Hepático/tratamento farmacológico , Resultado do Tratamento
2.
Oncol Res ; 20(5-6): 259-64, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23581233

RESUMO

Sunitinib, an orally multitargeted tyrosine kinase inhibitor and standard first-line treatment for metastatic renal cell carcinoma, is usually administered on a 6-week schedule. Toxicities reported with this drug are usually of moderate grade, which results in good treatment tolerability and patients' compliance. However, in some cases high-grade or prolonged toxicities require temporary treatment interruption or dose adjustment, possibly resulting in reduced treatment efficacy. We describe three cases of metastatic renal cell carcinoma patients (a 53-year-old male, a 70-year-old woman, and a 65-year-old woman) who received a shortened 3-week sunitinib administration schedule, 2 weeks daily administration followed by 1 week of rest (2/1) due to toxicities developed on the classic 6-week schedule, which would have required a temporary treatment interruption or a dose reduction. Treatment was generally well tolerated with manageable toxicities. A 3-week administration schedule of sunitinib may represent a valid alternative for managing toxicity while maintaining the planned dose intensity over a 6-weeks period of time. Sunitinib may thus be administered using a flexible dosing schedule to meet individual patient needs, achieving better tolerability and maintaining significant response to treatment.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma de Células Renais/tratamento farmacológico , Indóis/administração & dosagem , Neoplasias Renais/tratamento farmacológico , Pirróis/administração & dosagem , Idoso , Antineoplásicos/efeitos adversos , Carcinoma de Células Renais/patologia , Esquema de Medicação , Feminino , Humanos , Indóis/efeitos adversos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Pirróis/efeitos adversos , Sunitinibe
3.
Eur Rev Med Pharmacol Sci ; 26(10): 3787-3796, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35647861

RESUMO

OBJECTIVE: In a prospective study, SARS-CoV-2 IgG seroprevalence was assessed during the second pandemic wave (W2) in a cohort of Inflammatory Bowel Disease (IBD) patients using biologics. The secondary aim was to compare, in the same cohort, the frequency of seropositivity and of COVID-19 during the second vs. the first (W1) wave. PATIENTS AND METHODS: From November 2020 to March 2021, SARS-CoV-2 IgG seropositivity and the prevalence of COVID-19 were assessed in a cohort of IBD patients using biologics already studied at W1. INCLUSION CRITERIA: age ≥ 18 years; diagnosis of IBD; follow-up; written consent. EXCLUSION CRITERIA: SARS-CoV-2 vaccination. Risk factors for infection, compatible symptoms, history of infection or COVID-19, nasopharyngeal swab test were recorded. Data were expressed as median [range]. The χ2 test, Student's t-test, logistic regression analysis was used. RESULTS: IBD cohort at W1 and W2 included 85 patients: 45 CD (52.9%), 40 UC (47.1%). When comparing the same 85 patients at W2 vs. W1, a higher SARS-CoV-2 seroprevalence at W2 was at the limit of the statistical significance (9.4% vs. 2.3%; p=0.05). The prevalence of COVID-19 at W2 vs. W1 was 3.5% (3/85) vs. 0% (0/85) (p=0.08). Contacts with COVID-19 patients and symptoms compatible with COVID-19 were more frequent at W2 vs. W1 (18.8 % vs. 0%; p=0.0001; 34.1% vs. 15.3%; p=0.004). At W2, history of contacts and new onset diarrhea were more frequent in seropositive patients [4/8 (50%) vs. 12/77 (15.6%); p=0.01 and 4/8 (50%) vs. 2/77 (2.6%); p=0.0001]. At W2, the risk factors for seropositivity included cough, fever, new onset diarrhea, rhinitis, arthromyalgia, dysgeusia/anosmia at univariate (p<0.05), but not at multivariate analysis. History of contacts was the only risk factor for seropositivity at univariate (p=0.03), but not at multivariate analysis (p=0.1). CONCLUSIONS: During W2, characterized by a high viral spread, IBD and biologics appeared not to increase the prevalence of SARS-CoV-2 infection or COVID-19 disease. New onset diarrhea mimicking IBD relapse may be observed in patients with SARS-CoV-2 infection.


Assuntos
Produtos Biológicos , COVID-19 , Doenças Inflamatórias Intestinais , Adolescente , Anticorpos Antivirais , Produtos Biológicos/uso terapêutico , COVID-19/epidemiologia , Vacinas contra COVID-19 , Diarreia , Humanos , Imunoglobulina G , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/epidemiologia , Recidiva Local de Neoplasia , Pandemias , Estudos Prospectivos , SARS-CoV-2 , Estudos Soroepidemiológicos
4.
Ann Ig ; 23(2): 161-72, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-21770232

RESUMO

In industrialized Countries malnutrition is a very frequent condition in frail groups of the population, people with low income and elderly subjects above all if institutionalized. The aim of the study is to: analyse the prevalence of malnutrition in a sample of elderly people located in different geographical areas in Italy; identify the psychological, social, economic, environmental, cultural and demographic determinants of malnutrition. The prevalence of malnutrition (estimated through the MNA) is high in both sexes (28% of F and 21.9% of M. Age, institutionalisation, health status, autonomy status, cognitive status and education level are some of the factors that correlate with the presence of malnutrition. Loneliness and poverty seem to have a negative impact on nutritional status but further data are needed to confirm this hypothesis. The data collected confirm the need to activate services dedicated to assess the nutritional status of elderly people, to implement campaigns in particular on food education for the elderly population, to set tools and guide lines for caregivers.


Assuntos
Idoso Fragilizado , Avaliação Geriátrica , Solidão , Desnutrição/epidemiologia , Pobreza/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Cognição , Escolaridade , Feminino , Idoso Fragilizado/psicologia , Nível de Saúde , Humanos , Institucionalização/estatística & dados numéricos , Itália/epidemiologia , Solidão/psicologia , Masculino , Desnutrição/psicologia , Inquéritos Nutricionais , Educação de Pacientes como Assunto/métodos , Pobreza/psicologia , Prevalência , Fatores de Risco
5.
Eur Rev Med Pharmacol Sci ; 25(5): 2418-2424, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33755981

RESUMO

OBJECTIVE: Treatments used in Inflammatory Bowel Disease (IBD) have been associated with enhanced risk of viral infections and viral reactivation, however, it remains unclear whether IBD patients have increased risk of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. The aim of the study was to examine the prevalence of SARS-CoV-2 IgG positivity in IBD patients followed at our referral center. The role of treatments for IBD and risk factors for infection were also evaluated. PATIENTS AND METHODS: In a prospective study, all IBD patients followed at our referral centre between May 27th and July 21st, 2020 and fulfilling the inclusion criteria were tested for SARS-CoV-2 IgG. Specific IgG antibodies were evaluated by a commercial ELISA kit and SARS-CoV-2 nasopharyngeal swab was performed in seropositive patients. RESULTS: Two-hundred and eighteen patients, 128 Crohn's disease (CD) and 90 Ulcerative colitis (UC) [age 44, (19-77) years; ongoing biologics in 115 (52.7%)] were enrolled. No patient had major SARS-CoV-2-related symptoms. SARS-CoV-2 IgG were detected in 3 out of 218 (1.37%) patients with IBD (2 CD and 1 UC), all on biologics (2.6%). In all of the 3 seropositive patients, the nasopharyngeal swab was negative. There was no relationship between SARS-CoV-2 seroprevalence and the demographic/clinical characteristics of IBD patients. In contrast, history of recent travel was more frequent in the SARS-CoV-2 seropositive patients (2/3; 66.6%) than in SARS-CoV-2 seronegative patients [7/215 (3.25%); p<0.0001]. CONCLUSIONS: The prevalence of SARS-CoV-2 IgG seropositivity in IBD patients appears to be comparable to the non-IBD population and not influenced by ongoing treatments. Risk factors for infection common to the general non-IBD population should be considered when managing patients with IBD.


Assuntos
COVID-19/epidemiologia , Doenças Inflamatórias Intestinais/epidemiologia , Adulto , Idoso , Estudos de Coortes , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/virologia , Doença de Crohn/epidemiologia , Doença de Crohn/virologia , Feminino , Humanos , Doenças Inflamatórias Intestinais/virologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco , SARS-CoV-2/isolamento & purificação , Estudos Soroepidemiológicos
6.
Anal Bioanal Chem ; 398(2): 1017-23, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20607522

RESUMO

A specific, sensitive and robust liquid chromatography tandem mass spectrometry method for determining oxytetracycline, tetracycline, chlortetracycline and doxycycline in royal jelly and honey samples is presented. Extraction of drug residues was performed by ammonium acetate buffer as extractant followed by a clean-up with metal chelate affinity chromatography and solid-phase extraction. Tetracycline analysis was performed using liquid chromatography-electrospray ionisation-tandem mass spectrometry. The presented method is the first validated for royal jelly and in accordance with the requirements set by Commission Decision 2002/657/EC. Recoveries of the methods, calculated spiking the samples at 5.0, 10.0, 20.0 and 30.0 µg kg(-1), were 79% to 90% for honey and 77% to 90% for royal jelly. The intra-day precision (RSD) ranged between 8.1% and 15.0% for honey and from 9.1% to 16.3% for royal jelly, while inter-day precision values were from 10.2% to 17.6% and from 10.6% to 18.4% respectively for honey and royal jelly. Linearity for the four analytes was calculated from 5.0 to 50.0 µg kg(-1). The decision limits (CCα) ranged from 6.2 to 6.4 µg kg(-1) and from 6.1 to 6.5 µg kg(-1) for honey and royal jelly, respectively. Detection capabilities values (CCß) ranged between 7.2 and 7.7 µg kg(-1) and from 7.3 to 7.9 µg kg(-1) respectively for honey and royal jelly. The developed method is currently in use for confirmation of the official control analysis of honey and royal jelly samples.


Assuntos
Antibacterianos/análise , Ácidos Graxos/análise , Mel/análise , Espectrometria de Massas em Tandem/métodos , Tetraciclina/análise , Antibacterianos/isolamento & purificação , Clortetraciclina/análise , Clortetraciclina/isolamento & purificação , Cromatografia Líquida/métodos , Doxiciclina/análise , Doxiciclina/isolamento & purificação , Modelos Lineares , Oxitetraciclina/análise , Oxitetraciclina/isolamento & purificação , Sensibilidade e Especificidade , Extração em Fase Sólida/métodos , Tetraciclina/isolamento & purificação
7.
Eur Rev Med Pharmacol Sci ; 24(19): 10045-10050, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33090412

RESUMO

OBJECTIVE: Crohn's Disease (CD) has been associated with non-Hodgkin lymphoma. Follicular Lymphoma (FL) limited to the liver is extremely rare, accounting for 1% to 4.4% of all Primary Hepatic Lymphoma (PHL). CASE PRESENTATION: In 2018, an 85-years old male patient with post-operative recurrence of ileal CD referred rare episodes of fever and mild diffuse abdominal pain. Since cholecystectomy in 2001, clinical history was characterized by recurrent episodes of cholangitis and common bile duct stones. In 2018, ultrasonography and MRI showed a solid focal hepatic lesion (FHL)(4.5 cm x 2.5 cm) in the IV hepatic segment. The radiographic aspect of the lesion was unusual. Initially, focal nodular hyperplasia was suspected. Clinical history of cholangitis and radiological findings subsequently suggested a diagnosis of Hepatic Abscess (HA). A progressive enlargement of the FHL (7.3 cm x 5.8 cm) despite antibiotic treatments, led to perform a liver biopsy. Histological and immunophenotypical analysis of the FHL (7.5 cm x 5.4 cm) enabled a final diagnosis of FL. The "in situ" hybridization for Epstein-Barr virus (EBER) was negative. No additional lesions related to FL were initially detected, thus suggesting a very rare case of PHL in an old patient with CD never treated with thiopurines. CONCLUSIONS: This case report highlights the need to consider a rare diagnosis of FL of the liver in patients showing a challenging focal hepatic lesion of unknown origin.


Assuntos
Doença de Crohn/diagnóstico , Neoplasias Hepáticas/diagnóstico , Linfoma Folicular/diagnóstico , Idoso de 80 Anos ou mais , Humanos , Masculino
8.
Oncol Res ; 17(11-12): 565-70, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19806787

RESUMO

Androgen-independent prostate carcinoma (AICP) is one of the tumors that continue to respond poorly to chemotherapy. Recently, protocols based on the use of docetaxel have significantly improved survival for patients in this disease. In other types of neoplastic disease, combined therapy with taxanes and anthracycline derivatives has been shown to produce additive effects in terms of growth inhibition, and superior tolerability when associated with weekly administration schedules. These findings prompted us to examine the tolerability and efficacy of weekly treatment of AICP with docetaxel (DOX) plus epirubicin (EPI). We enrolled 35 chemotherapy-naive men with AICP (mean age 72 years, range 68-77) and normal hepatic, renal, and cardiac function. The chemotherapy protocol provided for the IV administration of DOX (30 mg/m2) and EPI (30 mg/m2) on days 1, 8, and 15 every 28 days. Treatment was continued for 6 months or until disease progression and/or unacceptable toxicity was observed. Serum levels of prostate-specific antigen (PSA) were monitored in all patients, and reductions from baseline values of >50% were considered indicative of positive responses to treatment. Thirty-four patients were included in the analysis of toxicity, and objective responses to treatment were assessed in the 28 patients with measurable lesions. Nineteen patients (56%) experienced PSA reductions of >50% that persisted for more than 4 weeks. The response to therapy was classified as complete in 1 of the 28 patients (4%) with measurable disease (at the lymph node level). Thirteen others (13/28, 46%) had partial responses, in nine (32%) the disease remained unchanged, and progression was observed in the remaining five (18%); overall response rate was 50% (CR + PR). Of the 27 patients with pain at the time of enrollment, 16 (59%) experienced pain reduction during treatment. The median time to disease progression was 11.7 months (95% CI: 7.7-15.7) while the median survival time was 18.7 months (95% CI: 12.3-25.1). During the study, four patients developed grade 3 anemia and leukopenia, which was reversible in all cases. Lower grades of asthenia, nausea, vomiting, diarrhea, and peripheral edema were also observed. There were no cases of cardiotoxic effects. Alopecia was frequent but reversible in all cases. The results of this preliminary study indicate that the combined administration of DOX and EPI for treatment of AIPC is effective and well tolerated. The weekly administration of the drug combination appears to be a promising approach to the treatment of these tumors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Idoso , Progressão da Doença , Docetaxel , Epirubicina/administração & dosagem , Humanos , Masculino , Neoplasias da Próstata/mortalidade , Taxoides/administração & dosagem
9.
Oncol Res ; 17(11-12): 559-64, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19806786

RESUMO

Single-agent gemcitabine has been established as standard treatment for advanced pancreatic cancer since clinical studies have shown an improvement in overall survival and significant clinical benefit when compared to the best supportive care despite low overall objective response. Several phase II studies have tested other single agents and different gemcitabine-based regimens in pancreatic cancer, but both response and survival rates have remained low. Irinotecan, a topoisomerase I inhibitor currently approved for the treatment of metastatic colon cancer, has also demonstrated improved response rate in patients with pancreatic cancer. Our purpose was to determine the activity and toxicity of this regimen in patients with unresectable or metastatic pancreatic cancer. Patients with histologically confirmed pancreatic adenocarcinoma received gemcitabine 1000 mg/m2 plus irinotecan 100 mg/m2 IV on days 1, 8, and 15 of a 28-day cycle for 6-8 months. From February 2004 to April 2006, 33 patients were entered into this study, 32 of whom were evaluable for treatment response, toxicity, median time to progression, and median survival. Characteristics included a median age of 63 years (range 41-79), 21 males (64%), and 12 females (36%). One patient discontinued treatment due to adverse effects. The total number of cycles administered was 188 and the median number of cycles for patients was 5.6 (range 2-7). Thirty-two patients were assessable for toxicity and response. Grade 3 hematological toxicity occurred in 9% of patients and was primarily neutropenia. No grade >2 gastrointestinal toxicities or death due to treatment were observed. The most frequent nonhematological adverse event was fatigue. Ten patients responded to treatment with two complete responses (6.3%) and eight partial responses (25.0%), for an overall response rate of 31.3%; 11 patients achieved stable disease (34.3%). The median time to tumor progression and the median survival were 9.2 (95% CI: 6.0-12.4) and 11.8 (95% CI: 7.7-15.9) months, respectively, with a 2-year survival of 22%. On the basis of this trial, the combination of gemcitabine plus irinotecan, administered in a weekly schedule and at this dose, is well tolerated and offers encouraging activity in the treatment of advanced and/or metastatic pancreatic cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Adenocarcinoma/mortalidade , Adulto , Idoso , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/análogos & derivados , Feminino , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Gencitabina
11.
Leukemia ; 20(10): 1783-9, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16838027

RESUMO

UNLABELLED: We assessed by multiparametric flow cytometry the levels of minimal residual disease (MRD) in 100 adult patients with acute myelogenous leukemia (AML) achieving complete remission after intensive chemotherapy. The aim of the study was to determine the optimal threshold, in terms of residual leukemic cells, and the time point of choice, that is, post-induction (post-Ind) or post-consolidation (post-Cons), able to better predict outcome. By applying the maximally selected log-rank statistics, the threshold discriminating MRD- from MRD+ cases was set at 3.5 x 10(-4) residual leukemic cells, a level that allowed the identification of distinct subgroups of patients, both at post-Ind and post-Cons time points. Post-Cons MRD- patients had a superior outcome in terms of relapse rate, overall survival (OS) and relapse-free survival (RFS) (P<0.001, for all comparisons), regardless of the MRD status after induction. In particular, patients entering MRD negativity only after consolidation showed the same outcome as those achieving early negativity after induction. Multivariate analysis, including karyotype, age, MDR1 phenotype, post-Ind and post-Cons MRD levels, indicated that the post-Cons MRD status independently affected relapse rate, OS and RFS (P<0.001, for all comparisons). IN CONCLUSION: (1) the threshold of 3.5 x 10(-4) is valid in discriminating risk categories in adult AML and (2) post-Cons MRD assessment is critical to predict disease outcome.


Assuntos
Leucemia Mieloide Aguda/mortalidade , Leucemia Mieloide Aguda/patologia , Neoplasia Residual/mortalidade , Neoplasia Residual/patologia , Adolescente , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Citometria de Fluxo , Humanos , Imunofenotipagem , Cinética , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico , Indução de Remissão , Análise de Sobrevida
12.
Nat Biotechnol ; 17(3): 292-6, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10096299

RESUMO

Flap endonucleases (FENs) isolated from archaea are shown to recognize and cleave a structure formed when two overlapping oligonucleotides hybridize to a target DNA strand. The downstream oligonucleotide probe is cleaved, and the precise site of cleavage is dependent on the amount of overlap with the upstream oligonucleotide. We have demonstrated that use of thermostable archaeal FENs allows the reaction to be performed at temperatures that promote probe turnover without the need for temperature cycling. The resulting amplification of the cleavage signal enables the detection of specific DNA targets at sub-attomole levels within complex mixtures. Moreover, we provide evidence that this cleavage is sufficiently specific to enable discrimination of single-base differences and can differentiate homozygotes from heterozygotes in single-copy genes in genomic DNA.


Assuntos
DNA/metabolismo , Sondas de Oligonucleotídeos , Polimorfismo de Fragmento de Restrição , Archaeoglobus fulgidus/genética , Bacteriófago M13/genética , DNA/isolamento & purificação , Endonucleases/genética , Exodesoxirribonuclease V , Exodesoxirribonucleases/genética , Leucócitos/metabolismo , Modelos Biológicos , Mutagênese Insercional , Pyrococcus furiosus/genética , Espectrometria de Fluorescência
13.
Nucleic Acids Res ; 29(15): 3248-57, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11470883

RESUMO

DNA sequence analysis by oligonucleotide binding is often affected by interference with the secondary structure of the target DNA. Here we describe an approach that improves DNA secondary structure prediction by combining enzymatic probing of DNA by structure-specific 5'-nucleases with an energy minimization algorithm that utilizes the 5'-nuclease cleavage sites as constraints. The method can identify structural differences between two DNA molecules caused by minor sequence variations such as a single nucleotide mutation. It also demonstrates the existence of long-range interactions between DNA regions separated by >300 nt and the formation of multiple alternative structures by a 244 nt DNA molecule. The differences in the secondary structure of DNA molecules revealed by 5'-nuclease probing were used to design structure-specific probes for mutation discrimination that target the regions of structural, rather than sequence, differences. We also demonstrate the performance of structure-specific 'bridge' probes complementary to non-contiguous regions of the target molecule. The structure-specific probes do not require the high stringency binding conditions necessary for methods based on mismatch formation and permit mutation detection at temperatures from 4 to 37 degrees C. Structure-specific sequence analysis is applied for mutation detection in the Mycobacterium tuberculosis katG gene and for genotyping of the hepatitis C virus.


Assuntos
Proteínas de Bactérias , Análise Mutacional de DNA/métodos , DNA de Cadeia Simples/química , DNA de Cadeia Simples/genética , Mutação/genética , Conformação de Ácido Nucleico , Regiões 5' não Traduzidas/genética , Sequência de Bases , Sondas de DNA/genética , Sondas de DNA/metabolismo , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Viral/química , DNA Viral/genética , Exonucleases/metabolismo , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Dados de Sequência Molecular , Mycobacterium tuberculosis/enzimologia , Mycobacterium tuberculosis/genética , Peroxidases/genética , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , Relação Estrutura-Atividade , Especificidade por Substrato , Taq Polimerase/metabolismo , Temperatura , Termodinâmica
14.
Nucleic Acids Res ; 29(16): E77, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11504885

RESUMO

Using microparticles as the capture surface and fluorescence resonance energy transfer as the detection technology, we have demonstrated the feasibility of performing the invasive cleavage reaction on a solid phase. An effective tool for many genomic applications, the solution phase invasive cleavage assay is a signal amplification method capable of distinguishing nucleic acids that differ by only a single base mutation. The method positions two overlapping oligonucleotides, the probe and upstream oligonucleotides, on the target nucleic acid to create a complex recognized and cleaved by a structure-specific 5'-nuclease. For microarray and other multiplex applications, however, the method must be adapted to a solid phase platform. Effective cleavage of the probe oligonucleotide occurred when either of the two required overlapping oligonucleotides was configured as the particle-bound reagent and also when both oligonucleotides were attached to the solid phase. Positioning probe oligonucleotides away from the particle surface via long tethers improved both the signal and the reaction rates. The particle-based invasive cleavage reaction was capable of distinguishing the ApoE Cys158 and Arg158 alleles at target concentrations as low as 100 amol/assay (0.5 pM).


Assuntos
Apolipoproteínas E/genética , Análise Mutacional de DNA/métodos , Polimorfismo de Nucleotídeo Único/genética , Alelos , Pareamento Incorreto de Bases/genética , Sequência de Bases , DNA/química , DNA/genética , DNA/metabolismo , Sondas de DNA/química , Sondas de DNA/genética , Sondas de DNA/metabolismo , Endodesoxirribonucleases/metabolismo , Transferência de Energia , Fluoresceína/metabolismo , Fluorescência , Corantes Fluorescentes/metabolismo , Humanos , Cinética , Microesferas , Conformação de Ácido Nucleico , Hibridização de Ácido Nucleico , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/genética , Oligodesoxirribonucleotídeos/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Mutação Puntual/genética , Sensibilidade e Especificidade , Soluções , Especificidade por Substrato , Titulometria
15.
J Mol Biol ; 297(2): 511-20, 2000 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-10715217

RESUMO

The formation of a duplex between two nucleic acid strands is restricted if one of the strands forms an intra- or intermolecular secondary structure. The formation of the new duplex requires the dissociation and replacement of the initial structure. To understand the mechanism of this type of kinetics we studied the replacement of a labeled DNA oligonucleotide probe bound to a complementary DNA target with an unlabeled probe of the same sequence. The replacement kinetics were measured using a gel-shift assay for 12, 14 and 16-nucleotide probes as a function of temperature and concentration of the unlabeled probe. The results demonstrate that the overall replacement rate is a combination of two kinetic pathways: dissociative and sequential displacement. The dissociative pathway occurs by the spontaneous dissociation of the initial duplex followed by association of the target and unlabeled probe. The sequential displacement pathway requires only the partial melting of the initial duplex to allow for the formation of a branched nucleation complex with the unlabeled probe, followed by the complete displacement of the labeled probe by migration of the branch point. The contribution from the dissociative pathway is predominant at temperatures close to the melting point of the labeled probe, whereas the contribution from the displacement pathway prevails at lower temperatures and when the concentration of the replacing unlabeled probe is high. The results show that at physiological conditions, duplex formation between a single-stranded oligonucleotide probe and a structured region of a target molecule occurs mainly by the sequential-displacement mechanism.


Assuntos
Pareamento de Bases/genética , DNA Complementar/química , DNA Complementar/metabolismo , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/metabolismo , Sítios de Ligação , Sondas de DNA/síntese química , Sondas de DNA/química , Sondas de DNA/genética , Sondas de DNA/metabolismo , DNA Complementar/síntese química , DNA Complementar/genética , Corantes Fluorescentes , Cinética , Modelos Químicos , Peso Molecular , Desnaturação de Ácido Nucleico , Hibridização de Ácido Nucleico , Oligodesoxirribonucleotídeos/síntese química , Oligodesoxirribonucleotídeos/genética , Concentração Osmolar , Temperatura , Termodinâmica
16.
Eur J Cancer ; 30A(4): 460-3, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7517150

RESUMO

From December 1988 to February 1991, 112 consecutive patients were submitted to epirubicin + mitomycin C chemotherapy as first-line treatment for advanced breast cancer. Epirubicin (75 mg/m2) was given every 3 weeks and mitomycin C (10 mg/m2) every 6 weeks. Only patients with visceral involvement or with a disease-free interval of less than 12 months were considered eligible. 102 patients were evaluated for response and toxicity in the present analysis. The main sites of involvement were viscera, soft tissues, bone in 71 (69.6%), 19 (18.6%) and 12 (11.8%) patients, respectively. Multiple site involvement was present in 66 (64.7%) cases. A total of 726 courses of therapy were administered (range 2-14; mean 7.2). Follow-up ranged from 96 to 210 weeks (median follow-up 138 weeks). Response rate was complete response (CR): 21.6% [95% confidence interval (CI) +/- 0.8], partial response (PR) 49.0% (95% CI +/- 0.1), stable disease (SD) 12.7% (95% CI +/- 0.1), progressive disease (PD) 16.7% (95% CI +/- 0.1), CR + PR: 70.6% (95% CI +/- 0.1). Median values of survival and time to progression were 79.4 and 42 weeks, respectively. At 2 years, 37.2 +/- 4.7% and 12.8 +/- 3.3% of the patients, respectively, were alive or without evidence of progression. Toxicity was generally mild. One hundred and four (14.3%) cycles in 53 patients were delayed due to haematological (82) or cardiac (3) toxicity, infectious disease (11) or causes not related to the treatment (8).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Anemia/induzido quimicamente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/mortalidade , Esquema de Medicação , Epirubicina/administração & dosagem , Feminino , Humanos , Leucopenia/induzido quimicamente , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Metástase Neoplásica , Cuidados Paliativos , Fatores de Tempo
17.
Eur J Cancer ; 36(8): 966-75, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10885599

RESUMO

From May 1991 to December 1996, 326 patients with advanced metastatic breast cancer were enrolled in a multicentre, randomised, phase III clinical trial with four arms. Patients were randomised to receive chemotherapy according to the FEC regimen (5-fluorouracil (5-FU) 500 mg/m2, epidoxorubicin (EPI) 75 mg/m2 and cyclophosphamide (CFA) 500 mg/m2, intravenously (i.v.). every 3 weeks) or the EM regimen (EPI 75 mg/m2, i.v. every 3 weeks; mitomycin C (MMC) 10 mg/m2, i.v. every 6 weeks) or the same regimens with the addition of lonidamine (LND) until disease progression (orally, thrice daily, 150+150+300 mg); a maximum of eight chemotherapy cycles were planned. The aim of the trial was 2-fold: to compare the EM regimen with the commonly used FEC regimen and to evaluate the possible role of the addition of LND. Patients were eligible if they had histologically proven breast carcinoma, metastatic or locoregional relapse with measurable and/or evaluable disease and were aged between 18 and 70 years: 318 patients were considered eligible. Patients with previous anthracycline-based adjuvant chemotherapy or those who relapsed within 6 months after any adjuvant chemotherapy regimen were excluded. Chemotherapy-related toxicity of grade > or = 3 was manageable and there was no significant difference between the arms in terms of haematological side-effects. The impact on heart function was mild. No increased toxicity was observed in the LND arms (apart from myalgias in 27-30% of the cases). A significant increase in the complete response rate was observed for the FEC/EM + LND group (20.4%) versus the FEC/EM group (10.8%). The median survival time and the median time to progression for the overall series were 608 days and 273 days, respectively; EM+/-LND achieved significantly improved survival and time to progression versus FEC+/-LND (P=0.01). This result was confirmed also when the analysis was restricted to patients previously treated with adjuvant CMF schedules. On the basis of these results, we conclude that EM may represent a valuable alternative to FEC for patients requiring a first-line regimen for advanced/ metastatic breast carcinoma, especially in patients previously treated with CMF in an adjuvant setting. Furthermore, we conclude that, in spite of a better complete response rate in the LND arms, as there was no clear advantage in time to progression or survival resulting from the addition of LND to the FEC or EM regimens, the routine use of LND is not warranted outside a clinical trial.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Algoritmos , Ciclofosfamida/administração & dosagem , Epirubicina/administração & dosagem , Feminino , Fluoruracila/administração & dosagem , Humanos , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Metástase Neoplásica , Análise de Sobrevida , Resultado do Tratamento
18.
Biotechniques ; 34(1): 198-203, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12545560

RESUMO

A new configuration of the solid-support invasive cleavage reaction provides a small reaction-volume format for high-sensitivity discrimination of nucleic acid targets with single nucleotide differences. With target concentrations as low as 2 amol/assay, the solid-support invasive cleavage reaction clearly distinguishes single base mutations. Two oligonucleotides tethered to the solid support hybridize to the target nucleic acid, forming a tripartite substrate that can be recognized and cleaved by Cleavase, a structure-specific 5'-nuclease. Each cleavage event yields fluorescence signal on the surface. When microspheres serve as the solid-support surface, analysis by fluorometer imparts real-time information about change in the reaction signal over time. Flow cytometry provides an alternative detection technology that collects endpoint information about the reaction signal on individual microspheres. A reaction volume of 10 microL with as few as 3000 microspheres is sufficient to distinguish single nucleotide differences at target concentrations less than 200 fM. This sensitivity level is within the range required for analysis of SNPs in genomic DNA. In addition, the flow cytometry format has multiplexing potential, making the microsphere-based invasive cleavage assay attractive for high-throughput genomic applications.


Assuntos
Análise Mutacional de DNA/métodos , Sondas de DNA/síntese química , DNA/genética , Citometria de Fluxo/métodos , Polimorfismo de Nucleotídeo Único/genética , Apolipoproteínas E/genética , Pareamento Incorreto de Bases/genética , Sequência de Bases , DNA/análise , Citometria de Fluxo/instrumentação , Microesferas , Dados de Sequência Molecular , Mutação Puntual/genética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodos
19.
Immunol Lett ; 6(1): 59-61, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6840815

RESUMO

The presence of circulating immune complexes (CIC) in a large number of malignancies was investigated in relation to the activity, the extent and the clinical course of the tumor clone. The aim of this study was to explore the relation between CIC serum levels and tumor growth in rats bearing the 130 Yoshida ascites hepatoma. For the assay of C3biCIC levels all samples were tested by a new competitive immunoenzymatic test. Experiments carried out on normal rats and on hepatoma-bearing ones, showed that during tumor growth values of CIC serum levels expressed as percent coefficient of inhibition are significantly higher in hepatoma-bearing rats (mean = 60.2) than in the normal controls (mean = 29.5). Furthermore CIC level and tumor proliferation are strictly correlated r = 0.9559. In this view sequential measurements of CIC levels may be valuable in establishing diagnosis, estimating prognosis and monitoring the behavior of neoplasia.


Assuntos
Complexo Antígeno-Anticorpo/análise , Circulação Sanguínea , Transformação Celular Neoplásica , Neoplasias Hepáticas Experimentais/imunologia , Animais , Masculino , Ratos , Ratos Endogâmicos
20.
Cancer Lett ; 125(1-2): 51-9, 1998 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-9566696

RESUMO

We tested the effects of daily melatonin treatment on the growth of the ascites hepatoma in rats, determining survival time, cell number and cell cycle phases at various stages of tumor development. Melatonin inhibited cellular proliferation, doubled mean life-time and increased survival. Thymidine incorporation in hepatoma cells from treated rats decreased significantly without changes in the apoptotic index. Flow cytometric analysis showed that melatonin slowed cell cycle progression by increasing the number of cells in phase G0G1. Thus, similar to in vitro models, melatonin's oncostatic action in vivo appears to be directed to specific cell cycle mechanisms, which remain to be elucidated.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Melatonina/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/patologia , Masculino , Ratos , Ratos Wistar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA