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1.
Ann Surg Oncol ; 20(11): 3438-45, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23709056

RESUMO

PURPOSE: To evaluate the oncologic safety and cosmetic results after breast cancer surgery for central breast cancer by the B technique. METHODS: Seventy women with operable breast cancer located in the central portion of the breast that had received resection surgery with the B technique were recruited. The primary outcome was the oncological safety, quantified as rate of positive resection margins and the cosmetic outcome evaluated by postsurgical self-assessment of the cosmetic outcome via questionnaire. The median follow-up period was 61.4 months (range 7.9-142.6 months). RESULTS: With one exception all patients had T1-2 tumors less than 5 cm in diameter. Most patients had invasive ductal breast cancers (57.1 %), followed by ductal carcinoma-in situ (27.1 %) and invasive lobular breast cancers (8.6 %). The incidence of positive resection margins was 17.1 %. No local tumor recurrence occurred during follow-up; one patient had distant metastases. In total, 80 % of the patients reported that the cosmetic results met or exceeded their expectations. CONCLUSIONS: The B technique is a safe breast conservation surgery for the excision of tumors located in the central portion of the breast and yields a high rate of satisfactory cosmetic results.


Assuntos
Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Carcinoma Intraductal não Infiltrante/cirurgia , Carcinoma Lobular/cirurgia , Mastectomia Segmentar , Recidiva Local de Neoplasia/cirurgia , Satisfação do Paciente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/psicologia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/psicologia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/psicologia , Carcinoma Lobular/patologia , Carcinoma Lobular/psicologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/psicologia , Estadiamento de Neoplasias , Complicações Pós-Operatórias , Prognóstico , Estudos Retrospectivos
3.
J Anal Toxicol ; 32(9): 768-73, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19021933

RESUMO

A 49-year-old man consumed two glasses (approximately 2 x 20 mL) of a beverage containing yellow gentian (Gentiana lutea). Shortly after ingestion, he developed nausea, vomiting, and oral paraesthesia. On admission to the hospital he suffered from severe bradycardia (35 beats/min) and hypotension (50/30 mm Hg), and he was treated with activated charcoal, antiemetics (metoclopramide, ondansetron), atropine, and intravenous electrolytic solution. The initial suspicion of Veratrum poisoning could be confirmed by identifying protoveratrines A (ProA) and protoveratrine B (ProB) in a sample from the beverage as well as in the patients serum by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS-MS). The yellow-colored beverage contained 25% ethanol (by headspace gas chromatography), 20.4 mg/L ProA, and 13.7 mg/L ProB. The serum concentration of ProA was 1162 ng/L and ProB was 402 ng/L. Veratridine, cevadine, and jervine were not detected, neither in the beverage nor in the serum sample. The lower limits of quantitation for all compounds is 10 microg/L (S/N > 10, beverage) and 100 ng/L (S/N > 10, serum). After treatment, the patient completely recovered from the symptoms within 24 h and was discharged from the hospital. The analytical method described was developed for the simultaneous identification and quantitation of five Veratrum alkaloids. The method is based on a liquid-liquid extraction followed by LC-MS-MS analysis. The time needed for analysis was 6 min.


Assuntos
Alcaloides de Veratrum/análise , Alcaloides de Veratrum/envenenamento , Veratrum/química , Veratrum/envenenamento , Acidentes , Bebidas Alcoólicas/análise , Bebidas Alcoólicas/envenenamento , Antídotos/uso terapêutico , Antieméticos/uso terapêutico , Carvão Vegetal/uso terapêutico , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Delgada , Gentiana , Hemodinâmica/efeitos dos fármacos , Humanos , Indicadores e Reagentes , Masculino , Espectrometria de Massas , Pessoa de Meia-Idade , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta
4.
Breast Cancer Res Treat ; 75(2): 175-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12243510

RESUMO

To evaluate the clinical value of MRI guided preoperative wire localization of clinically and mammographically occult lesions of the breast. In a multicenter study, we evaluated 132 preoperative MRI guided localizations. Median lesion size evaluated by MRI prior to wire localization was 9mm. MRI guided localization was successfully performed in 96.2% of cases. Median wire deviation from the lesion was 0 (0-10) mm. Moderate bleeding with no further treatment required occurred in three patients. We conclude that MRI guided preoperative wire localization is a safe and accurate procedure in cases of clinically and mammographically occult lesions of the breast.


Assuntos
Biópsia por Agulha/métodos , Neoplasias da Mama/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Imagem por Ressonância Magnética/métodos , Adulto , Idoso , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Desenho de Equipamento , Feminino , Humanos , Pessoa de Meia-Idade , Agulhas , Estudos Prospectivos
5.
Zentralbl Gynakol ; 123(9): 497-504, 2001 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-11709742

RESUMO

OBJECTIVE: The German Adjuvant Breast Cancer Study Group (GABG) conducts trials of preoperative chemotherapy in patients with primary breast cancer using a combination of doxorubicin and docetaxel (ADoc). - PATIENTS AND METHODS: We conducted a parallel-grouped phase IIa-study with 42 patients with a conventionally dosed and a dose-dense ADoc-schedule (4 cycles of Doxorubicin 50 mg/m(2), Docetaxel 75 mg/m(2) i. v. day 1, q day 15 or 22; G-CSF day 3-15 only for the dose-dense schedule) and a randomized phase IIb-study (GEPARDO-Study) with 250 patients with ADoc +/- Tamoxifen. Biological factors were determined immunohistochemically on 197 core biopsies before treatment. A comparison to a sequential AC-Doc regimen including 913 patients has been completed recently. - RESULTS: ADoc can be applicated on schedule in 93 % of all patients. The dose-dense regimen shows a tendency to more toxicity but also to more efficacy. The rate of complete pathological remissions (pCR) was 9.7 %. No difference was found between chemo- and chemoendocrine treatment. Clinically negative lymphnodes and a negative estrogen receptor status is predictive for a higher pCR-rate. To date no differences in toxicity could be found between ADoc and AC-Doc. - CONCLUSIONS: The dose-dense ADoc regimen is well tolerated and highly effective as preoperative therapy of breast cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Carcinoma/tratamento farmacológico , Terapia Neoadjuvante , Paclitaxel/análogos & derivados , Taxoides , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/cirurgia , Carcinoma/cirurgia , Quimioterapia Adjuvante , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Docetaxel , Doxorrubicina/administração & dosagem , Feminino , Alemanha , Humanos , Estudos Multicêntricos como Assunto , Paclitaxel/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto , Análise de Sobrevida , Tamoxifeno/administração & dosagem , Resultado do Tratamento
6.
Strahlenther Onkol ; 177(10): 504-10, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11680014

RESUMO

PURPOSE: We have retrospectively analyzed the impact of local recurrence in patients with adjuvant radiation therapy after mastectomy for breast cancer. PATIENTS AND METHODS: From January 1985 through December 1993, 959 patients were irradiated after mastectomy for breast cancer. The age ranged from 34 to 79 years, the median follow-up was 3.1 years (range: 0.3-12.2 years). 368 (38%) were pre- and 591 (62%) postmenopausal. 35% had T3-4 tumors, 62% had axillary lymph node involvement, and 66% received additional systemic hormonal and/or cytotoxic therapy. Postmastectomy radiotherapy was administered in case of positive axillary nodes and in high-risk pN0-patients. The chest wall and lymphatics (axilla, parasternal and supraclavicular nodes) were irradiated with an anterior photon field with 50 Gy and the chest wall with an electron field with 44 Gy in 2-Gy fractions. RESULTS: The overall survival was 70.5% after 5 and 59.8% after 10 years. 53 patients (5.5%) developed a locoregional recurrence 2-96 months after treatment (median 26 months). The local control rate was 92.7% after 5 and 86.4% after 10 years. Axillary lymph node involvement was the most important and (in a multivariate analysis the only) risk factor for local recurrence (p = 0.0001). Patients with local control had a significantly better 10-year distant-disease-free survival and overall survival as compared to patients with local recurrence (44.5% vs 15.4%, p = 0.002 and 62.1% vs 34.8%, p = 0.004). Local recurrence increased the risk of death by a factor of 1.7 and in a Cox regression model, axillary lymph node status, T-category and local recurrence were significant prognostic factors for overall survival. In patients with local recurrence, the initial axillary lymph node status was the most important prognostic factor for survival after local recurrence. The 3-year survival after local relapse was 86% for patients with pN0 status vs 27% in with positive axillary nodes (p = 0.025). CONCLUSIONS: Local recurrence after treatment of breast cancer with mastectomy + radiotherapy +/- systemic therapy is associated with a significantly higher risk of distant metastases and death. In this analysis, local recurrence was a strong and, besides lymph node status and T category, an independent risk factor for survival. Minimizing the risk of local recurrence is therefore an essential goal of a curative treatment concept.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/radioterapia , Recidiva Local de Neoplasia , Adulto , Fatores Etários , Idoso , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Terapia Combinada , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Metástase Linfática , Mastectomia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Prognóstico , Dosagem Radioterapêutica , Radioterapia Adjuvante , Análise de Regressão , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida , Fatores de Tempo
7.
Radiologe ; 41(6): 478-83, 2001 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-11458780

RESUMO

In a study, a radiofrequency (RF) treatment was performed on a patient with a small breast cancer after vacuum biopsy. As usual in cases with a malignant diagnosis, surgical excision and axillary dissection followed. Histopathology revealed some residual tumor in the margin of the cavity. It could not be distinguished from vital tumor on the hematotoxylin eosin (HE) stain. Based on the correlation of MRI and histopathology after subsequent surgical excision, we did, however, presume that the residual was contained within the zone of inactivation. Thus the hypothesis arose that, if too high temperatures can be avoided, it might be possible to inactivate tumor cells without significantly impairing histopathologic assessment. This hypothesis was supported by the following in vitro experiment performed on a fresh specimen: An RF treatment was performed using temperatures up to 70 degrees C only. Half of the specimen underwent HE-staining, the other half vitality testing. The results indicate that if a given temperature range is strictly observed it appears possible to inactivate tissue before tissue sampling, since histopathologic diagnosis will not be impaired. Further technologic improvements may eventually allow to develop a pre-treatment method which might permit to avoid potential hematogenous tumor spread during subsequent biopsy.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Hipertermia Induzida , Neoplasia Residual/patologia , Biópsia , Mama/patologia , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/cirurgia , Sobrevivência Celular , Terapia Combinada , Feminino , Humanos , Técnicas In Vitro , Pessoa de Meia-Idade , Neoplasia Residual/terapia , Valor Preditivo dos Testes
8.
Mol Biol Evol ; 18(6): 954-61, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11371583

RESUMO

Mariners are a large family of eukaryotic DNA-mediated transposable elements that move via a cut-and-paste mechanism. Several features of the evolutionary history of mariners are unusual. First, they appear to undergo horizontal transfer commonly between species on an evolutionary timescale. They can do this because they are able to transpose using only their own self-encoded transposase and not host-specific factors. One consequence of this phenomenon is that more than one kind of mariner can be present in the same genome. We hypothesized that two mariners occupying the same genome would not interact. We tested the limits of mariner interactions using an in vitro transposition system, purified mariner transposases, and DNAse I footprinting. Only mariner elements that were very closely related to each other (ca. 84% identity) cross-mobilized, and then inefficiently. Because of the dramatic suppression of transposition between closely related elements, we propose that to isolate elements functionally, only minor changes might be necessary between elements, in both inverted terminal repeat and amino acid sequence. We further propose a mechanism to explain mariner diversification based on this phenomenon.


Assuntos
Elementos de DNA Transponíveis/genética , DNA/metabolismo , Genoma , Transposases/genética , Animais , DNA/genética , Pegada de DNA , Evolução Molecular , Variação Genética , Insetos/genética , Dados de Sequência Molecular , Filogenia , Ligação Proteica , Sequências Repetidas Terminais/genética , Transposases/metabolismo
9.
Proc Natl Acad Sci U S A ; 98(9): 5110-5, 2001 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-11296265

RESUMO

Filamentous fungi are a large group of diverse and economically important microorganisms. Large-scale gene disruption strategies developed in budding yeast are not applicable to these organisms because of their larger genomes and lower rate of targeted integration (TI) during transformation. We developed transposon-arrayed gene knockouts (TAGKO) to discover genes and simultaneously create gene disruption cassettes for subsequent transformation and mutant analysis. Transposons carrying a bacterial and fungal drug resistance marker are used to mutagenize individual cosmids or entire libraries in vitro. Cosmids are annotated by DNA sequence analysis at the transposon insertion sites, and cosmid inserts are liberated to direct insertional mutagenesis events in the genome. Based on saturation analysis of a cosmid insert and insertions in a fungal cosmid library, we show that TAGKO can be used to rapidly identify and mutate genes. We further show that insertions can create alterations in gene expression, and we have used this approach to investigate an amino acid oxidation pathway in two important fungal phytopathogens.


Assuntos
Ascomicetos/genética , Genes Fúngicos/genética , Madurella/genética , Alelos , Clonagem Molecular , Cosmídeos/genética , Produtos Agrícolas/microbiologia , Elementos de DNA Transponíveis/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/fisiologia , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Genes Fúngicos/fisiologia , Biblioteca Genômica , Mutagênese Insercional/genética , Mutagênese Sítio-Dirigida/genética , Fenótipo , Reprodutibilidade dos Testes , Análise de Sequência de DNA , Transformação Genética
10.
J Bacteriol ; 182(19): 5391-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10986241

RESUMO

Now that the meningococcal genome sequence has been completed, the lack of a suitable method for saturation mutagenesis remains a major obstacle to the unraveling of the pathogenic propensity of Neisseria meningitidis. Here, we demonstrate that in vitro Himar1 mariner transposition on chromosomal or PCR-amplified meningococcal DNA, which is subsequently reintroduced into N. meningitidis by natural transformation, is an extremely efficient mutagenesis method. Southern blot analysis, sequencing the Himar1 insertion point in numerous transposition mutants, and a limited screening of the mutant libraries for clones impaired in maltose catabolism confirmed that Himar1 transposed randomly in N. meningitidis. Taken together, these data demonstrate that Himar1 in vitro transposition can lead to the exhaustive mutagenesis of N. meningitidis, allowing for the first time a genomic-scale mutational analysis of this important human pathogen.


Assuntos
Elementos de DNA Transponíveis , DNA Bacteriano , Neisseria meningitidis/genética , Cromossomos Bacterianos , Humanos , Mutagênese Sítio-Dirigida , Transformação Bacteriana
11.
Proc Natl Acad Sci U S A ; 97(17): 9665-70, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10920201

RESUMO

We present here a method for in vivo transposon mutagenesis of a methanogenic archaeon, Methanosarcina acetivorans C2A, which because of its independence from host-specific factors may have broad application among many microorganisms. Because there are no known Methanosarcina transposons we modified the mariner transposable element Himar1, originally found in the insect Hematobia irritans, to allow its use in this organism. This element was chosen because, like other mariner elements, its transposition is independent of host factors, requiring only its cognate transposase. Modified mini-Himar1 elements were constructed that carry selectable markers that are functional in Methanosarcina species and that express the Himar1 transposase from known Methanosarcina promoters. These mini-mariner elements transpose at high frequency in M. acetivorans to random sites in the genome. The presence of an Escherichia coli selectable marker and plasmid origin of replication within the mini-mariner elements allows facile cloning of these transposon insertions to identify the mutated gene. In preliminary experiments, we have isolated numerous mini-mariner-induced M. acetivorans mutants, including ones with insertions that confer resistance to toxic analogs and in genes that encode proteins involved in heat shock, nitrogen fixation, and cell-wall structures.


Assuntos
Elementos de DNA Transponíveis/genética , Proteínas de Ligação a DNA/genética , Genes Arqueais/genética , Genes de Insetos/genética , Methanosarcina/genética , Mutagênese Insercional/genética , Ácidos Alcanossulfônicos/farmacologia , Parede Celular/metabolismo , Clonagem Molecular , Análise Mutacional de DNA , DNA Recombinante/genética , Resistência Microbiana a Medicamentos/genética , Fluoracetatos/farmacologia , Marcadores Genéticos/genética , Proteínas de Choque Térmico/genética , Methanosarcina/efeitos dos fármacos , Fixação de Nitrogênio/genética , Plasmídeos/genética , Regiões Promotoras Genéticas/genética , Transformação Genética , Transposases/genética , Transposases/metabolismo
12.
Invest Radiol ; 35(12): 721-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11204798

RESUMO

RATIONALE AND OBJECTIVES: Previous studies using ultrasound CT or clinical amplitude/velocity reconstruction imaging ultrasound may indicate that cancers differ from normal breast tissue by increased sound velocity. However, only limited experience with direct measurements of sound velocity exists. This study aimed to investigate sound velocity measured directly in a variety of breast specimens. METHODS: Sound velocity was measured directly by forceps in fresh breast specimens chosen to contain one type of tissue only. Eighty specimens (31 cancers, 18 benign changes of glandular/fibrous tissue, 22 fatty tissues, 5 fibroadenomas, 2 compound tissues, 1 phylloides tumor, and 1 inflammation) were analyzed. RESULTS: Ultrasound velocities in carcinoma, benign changes, fibroadenoma, inflammation, and the phylloides tumor were very similar, with almost complete overlap. In contrary, the ultrasound velocity of fatty tissue was significantly lower. Compound tissues containing fat had an intermediate sound velocity. CONCLUSIONS: Sound velocity may add complementary information to echogenicity (B-scan). Because fat lobules exhibit low ultrasound velocity and carcinomas do not, a locally exact combination of ultrasound velocity information and reflexivity information should allow improved breast cancer detection by ultrasound.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Ultrassonografia Mamária , Feminino , Humanos
13.
MAGMA ; 11(3): 129-37, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11154954

RESUMO

PURPOSE: This retrospective study was undertaken to investigate the morphologic and dynamic features of in situ and minimally invasive breast cancer on contrast-enhanced (c.-e.) MR imaging and to examine possible associations to pathology features. MATERIAL AND METHODS: A total of 71 patients underwent MR imaging. T1-weighted FLASH-3D images were obtained before and after intravenous administration of Gd-DTPA. Histopathologic analysis of 78 lesions revealed ductal carcinoma in situ (DCIS) n = 50 and DCIS with microinvasion n = 28. MR features were correlated with histopathologic findings. RESULTS: Enhancement in DCIS was focal (73%), diffuse (10%) or ductal (17%). No enhancement occurred in two cases (4%). In 65% enhancement speed was classified as delayed. There was a tendency toward a more ill-defined (83 vs. 43%) enhancement pattern in high grade DCIS and a more ductal (29 vs. 12%) and faster (50 vs. 29%) enhancement in comedo type DCIS. However, significant differences in the enhancement behaviour could neither be demonstrated between high grade and non high grade DCIS nor between comedo and non comedo type DCIS. No significant differences were noted between pure and microinvasive DCIS. CONCLUSION: In this retrospective analysis the majority (96%) of DCIS lesions show contrast enhancement. However, in only about 50% of DCIS the criteria of a so-called 'typical' enhancement behaviour was fulfilled, that means strong, early, focal ill-circumscribed or ductal. Enhancement that follows a duct is often associated with malignancy, however this feature was only present in 17% of the cases. c.-e. MR imaging allowed the detection of 25 additional foci of DCIS. Therefore malignant in situ lesions can be present with atypical enhancement, and should be taken into consideration in high-risk patients in particular.


Assuntos
Neoplasias da Mama/diagnóstico , Carcinoma in Situ/diagnóstico , Carcinoma Ductal de Mama/diagnóstico , Imagem por Ressonância Magnética/métodos , Adulto , Idoso , Neoplasias da Mama/patologia , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/patologia , Meios de Contraste , Erros de Diagnóstico , Feminino , Gadolínio DTPA , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estudos Retrospectivos
14.
Insect Biochem Mol Biol ; 29(10): 883-97, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10528409

RESUMO

Morphogenesis is a complex process operating at several levels of organization--organism, tissues, cells, and molecules. Complex interactions occur between and within these levels. Many of the molecules that mediate these interactions are predictably turning out to be large multidomain proteins. Here we describe one such novel protein associated with remodeling of epithelial monolayers in embryos and developing wings of the moth Manduca sexta. On the basis of its sequence and its expression pattern along lacunae of developing wings, we propose the name lacunin for this extracellular matrix protein that contains nine different types of domains, most of which are present in multiple copies. These include domains of various types: Kunitz proteinase inhibitors, thrombospondin type I, immunoglobulin-like, and several newly defined domains of unknown function (PAL, PLAC, and lagrin domains). This rich patchwork of distinct domains probably exerts multiple effects on a variety of cell behaviors associated with the complex phenomenon of epithelial morphogenesis.


Assuntos
Proteínas da Matriz Extracelular/fisiologia , Proteínas de Insetos , Manduca/crescimento & desenvolvimento , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Sítios de Ligação , Caenorhabditis elegans , Células Epiteliais , Proteínas da Matriz Extracelular/biossíntese , Proteínas da Matriz Extracelular/genética , Humanos , Camundongos , Dados de Sequência Molecular , Morfogênese , Homologia de Sequência de Aminoácidos
15.
Eur Radiol ; 9(8): 1656-65, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10525886

RESUMO

The aim of this study was the realisation and clinical application of MR-guided vacuum biopsy for percutaneous excisional and incisional biopsy of enhancing breast lesions. A breast biopsy system and procedure have been developed which allow precise and safe access to breast lesions in any location and use of vacuum biopsy (VB) under MR guidance. Fifty-one patients with 55 MR-detected lesions were examined. Verification of these diagnoses included re-excision histology of all 14 malignancies and for benign lesions retrospective correlation of histology and imaging, assessment of complete or partial removal of the enhancing area directly after VB (40 of 40 lesions) and follow-up MRI (33 of 40 lesions), which in contrast to conventional needle biopsy can be used as proof of representative removal. Fifty-four of 55 procedures (including 15 lesions

Assuntos
Neoplasias da Mama/patologia , Mama/patologia , Imagem por Ressonância Magnética , Biópsia/instrumentação , Biópsia/métodos , Feminino , Humanos , Imagem por Ressonância Magnética/instrumentação , Vácuo
16.
Proc Natl Acad Sci U S A ; 96(20): 11428-33, 1999 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-10500193

RESUMO

Mariner-family transposable elements are active in a wide variety of organisms and are becoming increasingly important genetic tools in species lacking sophisticated genetics. The Himar1 element, isolated from the horn fly, Haematobia irritans, is active in Escherichia coli when expressed appropriately. We used this fact to devise a genetic screen for hyperactive mutants of Himar1 transposase that enhance overall transposition from approximately 4- to 50-fold as measured in an E. coli assay. Purified mutant transposases retain their hyperactivity, although to a lesser degree, in an in vitro transposition assay. Mutants like those described herein should enable sophisticated analysis of the biochemistry of mariner transposition and should improve the use of these elements as genetic tools, both in vivo and in vitro.


Assuntos
Elementos de DNA Transponíveis , Muscidae/genética , Transposases/genética , Animais , DNA/metabolismo , Mutação
17.
Proc Natl Acad Sci U S A ; 96(4): 1645-50, 1999 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-9990078

RESUMO

mariner family transposons are widespread among eukaryotic organisms. These transposons are apparently horizontally transmitted among diverse eukaryotes and can also transpose in vitro in the absence of added cofactors. Here we show that transposons derived from the mariner element Himar1 can efficiently transpose in bacteria in vivo. We have developed simple transposition systems by using minitransposons, made up of short inverted repeats flanking antibiotic resistance markers. These elements can efficiently transpose after expression of transposase from an appropriate bacterial promoter. We found that transposition of mariner-based elements in Escherichia coli produces diverse insertion mutations in either a targeted plasmid or a chromosomal gene. With Himar1-derived transposons we were able to isolate phage-resistant mutants of both E. coli and Mycobacterium smegmatis. mariner-based transposons will provide valuable tools for mutagenesis and genetic manipulation of bacteria that currently lack well developed genetic systems.


Assuntos
Elementos de DNA Transponíveis , Escherichia coli/genética , Mycobacterium smegmatis/genética , Mycobacterium tuberculosis/genética , Bacteriófago lambda/genética , Sequência de Bases , Conjugação Genética , Cianobactérias/genética , Proteínas de Ligação a DNA , Mutagênese Insercional , Fases de Leitura Aberta , Plasmídeos , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Rhodobacter capsulatus/genética , Streptomyces/genética , Transposases
18.
Rofo ; 171(6): 480-4, 1999 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-10668514

RESUMO

PURPOSE: The study aimed to investigate ultrasound velocity (SV) in carcinomas, fibrocystic changes, fibroadenomas and fatty tissue of the female breast by means of direct in-vitro measurements. We intended to test whether or not differences in SV exist between the various types of tissue and whether the SV is a useful criterion to differentiate the different tissues. METHOD: SV was measured by comparing transmission time of the ultrasound beam through the specimen and through water. Altogether 40 specimens (12 cancer, 14 fibrocystic changes = FCD, 10 fatty tissues, 3 fibroadenomas, and 1 mixed tissue) were analysed. RESULTS: Velocity differed significantly between fat (1478.5 +/- 6.5 m/s) and tumor (1523.1 +/- 5.9 m/s) (p approximately 10(-11)) and between fat and FCD (1526.0 +/- 9.0 m/s) (p approximately 10(-12)). No significant differences and much overlap were seen between the ultrasound velocities of tumors and FCD. Ultrasound velocity in fibroadenomas (1533.2 +/- 3.8 m/s) was comparable with that in carcinomas and FCD. CONCLUSIONS: We conclude that ultrasound velocity may add complementary information to echogenicity (B-scan). Thus, a locally exact correlation of echogenicity and sound velocity might allow for an improved tissue characterization.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Carcinoma/diagnóstico por imagem , Fibroadenoma/diagnóstico por imagem , Doença da Mama Fibrocística/diagnóstico por imagem , Ultrassonografia Mamária , Diagnóstico Diferencial , Feminino , Humanos , Técnicas In Vitro , Ultrassonografia Mamária/instrumentação , Ultrassonografia Mamária/métodos , Ultrassonografia Mamária/estatística & dados numéricos
19.
Nucleic Acids Res ; 26(16): 3687-93, 1998 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-9685483

RESUMO

Mariner transposons belong to the mariner /Tc1 superfamily of class II, DNA-mediated elements. One of these transposons, Himar1 , isolated from the horn fly, is independent of host-specific factors that would limit transfer between different species, making it an ideal candidate for gene transfer technology development. To determine the activity of Himar1 transposase in mammalian cells, we introduced the Himar1 transposase gene into an adenovirus (Ad) vector under control of the phage T7 RNA polymerase promoter. Mammalian cells infected with the Ad vector carrying the Himar1 gene efficiently expressed the Himar1 transposase in the presence of T7 polymerase. In in vitro inter-plasmid transposition reactions, Himar1 transposase expressed by the Ad vector mediated precise cut-and-paste transposition and resulted in a characteristic duplication of TA at the integration site of the target plasmid. Further studies showed that this transposase was capable of catalyzing transposition between twoplasmids co-transfected into 293T7pol cells, which express T7 RNA polymerase. Combining the integration capability of mariner transposons with the transduction efficiency of Ad vectors is expected to provide a powerful tool for introducing transgenes into the host chromosome.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Ligação a DNA , Transposases/genética , Transposases/metabolismo , Adenoviridae/genética , Animais , Sequência de Bases , Linhagem Celular , Clonagem Molecular , Elementos de DNA Transponíveis , DNA Recombinante/genética , Expressão Gênica , Vetores Genéticos , Humanos , Modelos Genéticos , Sondas de Oligonucleotídeos/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transfecção
20.
Proc Natl Acad Sci U S A ; 95(15): 8927-32, 1998 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-9671781

RESUMO

Although the complete DNA sequences of several microbial genomes are now available, nearly 40% of the putative genes lack identifiable functions. Comprehensive screens and selections for identifying functional classes of genes are needed to convert sequence data into meaningful biological information. One particularly significant group of bacterial genes consists of those that are essential for growth or viability. Here, we describe a simple system for performing transposon mutagenesis on naturally transformable organisms along with a technique to rapidly identify essential or conditionally essential DNA segments. We show the general utility of this approach by applying it to two human pathogens, Haemophilus influenzae and Streptococcus pneumoniae, in which we detected known essential genes and assigned essentiality to several ORFs of unknown function.


Assuntos
Genes Bacterianos , Haemophilus influenzae/genética , Streptococcus pneumoniae/genética , Sequência de Bases , Primers do DNA , Elementos de DNA Transponíveis , Proteínas de Ligação a DNA , Mutagênese , Fases de Leitura Aberta , Transposases
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