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1.
Front Microbiol ; 14: 1171770, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37234529

RESUMO

Bovine herpesvirus 4 (BoHV-4) is a Gammaherpesvirus belonging to the Rhadinovirus genus. The bovine is BoHV-4's natural host, and the African buffalo is BoHV-4's natural reservoir. In any case, BoHV-4 infection is not associated with a specific disease. Genome structure and genes are well-conserved in Gammaherpesvirus, and the orf 45 gene and its product, ORF45, are one of those. BoHV-4 ORF45 has been suggested to be a tegument protein; however, its structure and function have not yet been experimentally characterized. The present study shows that BoHV-4 ORF45, despite its poor homology with other characterized Rhadinovirus ORF45s, is structurally related to Kaposi's sarcoma-associated herpesvirus (KSHV), is a phosphoprotein, and localizes in the host cell nuclei. Through the generation of an ORF45-null mutant BoHV-4 and its pararevertant, it was possible to demonstrate that ORF45 is essential for BoHV-4 lytic replication and is associated with the viral particles, as for the other characterized Rhadinovirus ORF45s. Finally, the impact of BoHV-4 ORF45 on cellular transcriptome was investigated, an aspect poorly explored or not at all for other Gammaherpesvirus. Many cellular transcriptional pathways were found to be altered, mainly those involving p90 ribosomal S6 kinase (RSK) and signal-regulated kinase (ERK) complex (RSK/ERK). It was concluded that BoHV-4 ORF45 has similar characteristics to those of KSHV ORF45, and its unique and incisive impact on the cell transcriptome paves the way for further investigations.

2.
Front Endocrinol (Lausanne) ; 12: 624102, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33716976

RESUMO

Gemcitabine plus Capecitabine (Gem/Cape) is a frequently adopted second line chemotherapy for metastatic adrenocortical carcinoma (ACC), but only a minority of patients is destined to obtain a clinical benefit. The identification of baseline predictive factors of efficacy is relevant. We retrospectively analyzed clinical data from 50 consecutive patients with metastatic progressing ACC treated between 2011 and 2019. Patients received intravenous Gemcitabine and oral Capecitabine on a metronomic schedule. Previous mitotane therapy was maintained. Clinical benefit (partial response + stable disease) at 4 months was 30%, median progression-free survival (PFS) and disease-specific survival (DSS) from Gem/Cape start were 3 and 8 months, respectively. Among clinical variables evaluated before the start of Gem/Cape, presence of ECOG performance status ≥1 [HR 6.93 95% confidence interval (CI) 0.03-0.54, p.004] and neutrophil-to-lymphocyte ratio (NLR) ≥5 [HR 3.88, 95% (CI) 0.81-0.90, p.003] were independent indicators of poor PFS at multivariate analysis. Conversely, surgery of primary tumor, the presence of lung or lymph-node metastases, blood mitotane level, anemia, and the Advanced Lung cancer Inflammation index (ALI) failed to be independently associated. This study confirms that the Gem/Cape schedule is modestly active in heavily pretreated ACC patients (28% received at least two previous chemotherapy lines). NLR and performance status (PS) are easily available clinical parameters that are helpful to identify patients not likely to derive significant advantage from Gem/Cape chemotherapy.


Assuntos
Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Carcinoma Adrenocortical/tratamento farmacológico , Antineoplásicos/uso terapêutico , Capecitabina/uso terapêutico , Desoxicitidina/análogos & derivados , Neoplasias Pulmonares/tratamento farmacológico , Metástase Linfática/tratamento farmacológico , Adolescente , Neoplasias do Córtex Suprarrenal/patologia , Carcinoma Adrenocortical/secundário , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Desoxicitidina/uso terapêutico , Feminino , Humanos , Neoplasias Pulmonares/secundário , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem , Gencitabina
3.
Cancers (Basel) ; 12(4)2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32290298

RESUMO

Etoposide, doxorubicin and cisplatin plus oral mitotane (EDP-M) comprise the reference regimen in the management of patients with adrenocortical carcinoma (ACC). In this paper, we described the outcome of 58 patients with advanced/metastatic ACC consecutively treated with EDP-M in a reference center for this rare disease in Italy. In this series, EDP-M obtained a partial response in 50% of patients; median progression free survival (PFS) and overall survival were 10.1 months (95% Confidence Interval [CI 95%] 8.1-12.8) and 18.7 months (95% CI: 14.6-22.8), respectively. EDP-M was not interrupted in five patients showing disease progression after two cycles without the appearance of new lesions and mitotane levels below the therapeutic range. In two of them, the disease remained stable at further imaging evaluations and the other three obtained a partial response. Twenty-six responding patients underwent surgery of residual disease and 13 of them became disease free. Surgery identified a pathological complete response (pCR) in four patients (7%) and Ki67 expression in post-chemotherapy tumor specimens, inferior to 15% (median value), was associated with better PFS and survival. In the present study, the EDP-M regimen is confirmed to have a limited efficacy. Early disease progression does not mean treatment inefficacy. Surgery of residual disease in partially responding patients allows for the detection of pCR in few of them and this condition is predictive of long-term survival. Ki67 expression of post-chemotherapy residual disease could be an additional prognostic factor that deserves to be studied further.

4.
Nat Genet ; 51(5): 885-895, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30962619

RESUMO

The domestication of wild emmer wheat led to the selection of modern durum wheat, grown mainly for pasta production. We describe the 10.45 gigabase (Gb) assembly of the genome of durum wheat cultivar Svevo. The assembly enabled genome-wide genetic diversity analyses revealing the changes imposed by thousands of years of empirical selection and breeding. Regions exhibiting strong signatures of genetic divergence associated with domestication and breeding were widespread in the genome with several major diversity losses in the pericentromeric regions. A locus on chromosome 5B carries a gene encoding a metal transporter (TdHMA3-B1) with a non-functional variant causing high accumulation of cadmium in grain. The high-cadmium allele, widespread among durum cultivars but undetected in wild emmer accessions, increased in frequency from domesticated emmer to modern durum wheat. The rapid cloning of TdHMA3-B1 rescues a wild beneficial allele and demonstrates the practical use of the Svevo genome for wheat improvement.


Assuntos
Triticum/genética , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Cádmio/metabolismo , Cromossomos de Plantas/genética , Domesticação , Variação Genética , Genoma de Planta , Filogenia , Melhoramento Vegetal , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Seleção Genética , Sintenia , Tetraploidia , Triticum/classificação , Triticum/metabolismo
5.
PLoS One ; 13(11): e0206993, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30439980

RESUMO

The α-zein gene family encodes the most abundant storage proteins of maize (Zea mays) endosperm. Members of this family are expressed in a parent-of-origin manner. To characterize this phenomenon further, we investigated the expression of a subset of α-zein polypeptides in reciprocal crosses between o2 lines that were characterized by a simplified α-zein pattern. Maize lines that suppressed the expression of α-zeins when used as female parents were identified. The suppression was cross-specific, occurring only when specific genetic backgrounds were combined. Four α-zein sequences that were sensitive to uniparental expression were isolated. Molecular characterization of these α-zeins confirmed that their expression or suppression depended on the genetic proprieties of the endosperm tissue instead of their parental origin. DNA methylation analysis of both maternally and paternally expressed α-zeins revealed no clear correlation between this epigenetic marker and parent-of-origin allelic expression, suggesting that an additional factor(s) is involved in this process. Genetic analyses revealed that the ability of certain lines to suppress α-zein expression was unstable after one round of heterozygosity with non-suppressing lines. Interestingly, α-zeins also showed a transgressive expression pattern because unexpressed isoforms were reactivated in both F2 and backcross plants. Collectively, our results suggest that parent-of-origin expression of specific α-zein alleles depends on a complex interaction between genotypes in a manner that is reminiscent of paramutation-like phenomena.


Assuntos
Proteínas de Plantas/metabolismo , Zea mays/metabolismo , Zeína/metabolismo , Alelos , Sequência de Aminoácidos , Quimera/genética , Metilação de DNA , DNA de Plantas/química , DNA de Plantas/genética , DNA de Plantas/metabolismo , Endosperma/metabolismo , Regulação da Expressão Gênica de Plantas , Genótipo , Proteínas de Plantas/genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Alinhamento de Sequência , Zeína/genética
6.
Tissue Eng Part C Methods ; 24(10): 596-604, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30234462

RESUMO

Conditioned medium (CM) and microvesicles (MVs) are produced using different protocols: CM is collected following 12-96 h of cell culture without renewal of tissue culture medium, while MVs are collected after overnight cell culture. For future comparative studies in regenerative medicine looking at the efficacy of CM and MVs, it is important to understand how the quality of cell secretions is affected by culture. The aim of this study was to evaluate whether the duration of culturing influences the micro-RNAs (miRNAs) cargo of equine amniotic mesenchymal cells (AMCs) and their MVs. The analysis identified 990 miRNAs. After one night, there were 347 differently expressed (DE)-miRNAs between MVs and cells, whereas after four nights there were 359. About 58.3% of the DE-miRNAs were shared between samples produced under the two conditions. The comparison between miRNA content in AMC cells cultured for one night versus four nights showed eight DE-Equus caballus (eca)-miRNAs, which target genes were involved in immune response to external stimulus, inflammatory response, and production of reactive oxygen species. Comparing MVs isolated from one or four nights, four DE-miRNAs that target genes regulating cell cycle progression and production of reactive oxygen species were found, but only eca-miR-214 was enriched in the MVs after four nights. In conclusion, after 4 days of cell culture, the profile of AMC miRNAs was altered, indicating a probable phenotypic transition versus a new cell culture environment and aging. After this time, MVs accumulated eca-miR-214, which may help cells survive or adapt to new culture conditions.


Assuntos
Âmnio/citologia , Técnicas de Cultura de Células/métodos , Micropartículas Derivadas de Células/metabolismo , Células-Tronco Mesenquimais/citologia , MicroRNAs/genética , Animais , Forma Celular , Regulação da Expressão Gênica , Cavalos , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/metabolismo , Análise de Componente Principal , Fatores de Tempo
7.
Support Care Cancer ; 26(8): 2929-2935, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29546526

RESUMO

PURPOSE: Trabectedin is one of the few active agents in soft tissue sarcoma (STS) but hepatotoxicity is frequent and represents a dose-limiting factor. Protective strategies aiming at counteracting this important side effect have a crucial clinical impact. Due to its antioxidant properties, N-acetylcysteine (NAC) has a recognized hepatoprotective effect and this provides the rationale for testing NAC in the management of trabectedin-induced hepatotoxicity. METHODS: Patients with recurrent or metastatic soft tissue sarcoma, consecutively observed at our institution, who were considered eligible to trabectedin, received concomitant NAC if they had impaired hepatic or renal function at baseline or developed hepatotoxicity during treatment. The study aim was to retrospectively explore trabectedin administration in terms of number of cycles, mean dose, and dose intensity (DI) in patients who received NAC as compared with those who did not. Secondary end points were progression-free survival (PFS) and overall survival (OS). RESULTS: A total number of 18 patients were enrolled in this study. Nine received NAC and nine did not. The median number of administered trabectedin cycles, mean trabectedin dose/cycles, and median DI was comparable in the two groups (p = 0.450, p = 0.534, and p = 0.450, respectively). The PFS and OS curves overlapped. CONCLUSION: This explorative study suggests that NAC can have a hepatoprotective activity in patients receiving trabectedin allowing to maintain an adequate dose intensity and continuative administration in patients with impaired liver and renal function or developing treatment-induced hepatotoxicity. A prospective randomized trial is warranted.


Assuntos
Acetilcisteína/uso terapêutico , Antineoplásicos Alquilantes/toxicidade , Fígado/patologia , Sarcoma/complicações , Trabectedina/toxicidade , Acetilcisteína/farmacologia , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sarcoma/tratamento farmacológico , Sarcoma/patologia
9.
Pharmacology ; 100(5-6): 261-268, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28797006

RESUMO

BACKGROUND: The administration of abiraterone acetate (abiraterone) leads to an adrenocorticotropic hormone (ACTH)-driven increase in mineralocorticoid hormones, requiring glucocorticoid supplementation that may stimulate the growth of prostate cancer (PCa). Amiloride is a drug that selectively reduces the aldosterone-sensitive Na+/K+ exchange and could be effective in the management of mineralocorticoid excess syndrome (MCES). METHODS: The efficacy of amiloride + hydrochlorothiazide (HCT) in the clinical management of abiraterone-induced MCES was assessed in 5 consecutive patients with castration-resistant PCa (CRPC). Then, using the in vitro experimental model of PCa cell lines, the possible effects of drugs usually used in the clinical management of CRPC patients on PCa cell viability were investigated. RESULTS: Amiloride/HCT led to a complete disappearance of all clinical and biochemical signs of abiraterone-induced MCES in the 5 treated patients. The in vitro study showed that abiraterone treatment significantly decreased cell viability of both androgen receptor (AR)-expressing VCaP (vertebral-cancer of the prostate) and LNCaP (lymph node carcinoma of the prostate) cells, with no effect on AR-negative PC-3 cells. Prednisolone, spironolactone, and eplerenone increased LNCaP cell viability, while amiloride reduced it. The non-steroid aldosterone antagonist PF-03882845 did not modify PCa cell viability. CONCLUSIONS: The combination of amiloride/HCT was effective in the management of abiraterone-induced MCES. Amiloride did not negatively interfere with the abiraterone inhibition of PCa cell viability in vitro.


Assuntos
Amilorida/farmacologia , Androstenos/farmacologia , Antineoplásicos/farmacologia , Síndrome de Excesso Aparente de Minerolocorticoides/induzido quimicamente , Síndrome de Excesso Aparente de Minerolocorticoides/tratamento farmacológico , Mineralocorticoides/metabolismo , Androgênios/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Combinação de Medicamentos , Humanos , Hidroclorotiazida/farmacologia , Masculino , Síndrome de Excesso Aparente de Minerolocorticoides/metabolismo , Neoplasias da Próstata/tratamento farmacológico
10.
PLoS One ; 11(10): e0164461, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27760169

RESUMO

Paratuberculosis in cattle is a chronic granulomatous gastroenteritis caused by Mycobacterium avium subsp. paratubercolosis (MAP) which is endemic worldwide. In dairy herds, it is responsible for huge economic losses. However, current diagnostic methods do not detect subclinical infection making control of the disease difficult. The identification of MAP infected animals during the sub-clinical phase of infection would play a key role in preventing the dissemination of the pathogen and in reducing transmission. Gene expression and circulating microRNA (miRNA) signatures have been proposed as biomarkers of disease both in the human and veterinary medicine. In this paper, gene expression and related miRNA levels were investigated in cows positive for MAP, by ELISA and culture, in order to identify potential biomarkers to improve diagnosis of MAP infection. Three groups, each of 5 animals, were used to compare the results of gene expression from positive, exposed and negative cows. Overall 258 differentially expressed genes were identified between unexposed, exposed, but ELISA negative and positive groups which were involved in biological functions related to inflammatory response, lipid metabolism and small molecule biochemistry. Differentially expressed miRNA was also found among the three groups: 7 miRNAs were at a lower level and 2 at a higher level in positive animals vs unexposed animals, while 5 and 3 miRNAs were respectively reduced and increased in the exposed group compared to the unexposed group. Among the differentially expressed miRNAs 6 have been previously described as immune-response related and two were novel miRNAs. Analysis of the miRNA levels showed correlation with expression of their target genes, known to be involved in the immune process. This study suggests that miRNA expression is affected by MAP infection and play a key role in tuning the host response to infection. The miRNA and gene expression profiles may be biomarkers of infection and potential diagnostic of MAP infection earlier than the current ELISA based diagnostic tests.


Assuntos
Doenças dos Bovinos/imunologia , Perfilação da Expressão Gênica , Imunidade Inata , MicroRNAs/sangue , Mycobacterium avium subsp. paratuberculosis/fisiologia , Paratuberculose/imunologia , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Bovinos , Doenças dos Bovinos/sangue , Doenças dos Bovinos/genética , Indústria de Laticínios , Redes Reguladoras de Genes , Paratuberculose/sangue , Paratuberculose/genética
11.
Tumori ; 100(3): 272-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25076237

RESUMO

AIMS AND BACKGROUND: Radiotherapy is the standard treatment of glioblastoma. Three-dimensional conformal radiotherapy is the standard technique to treat glioblastoma. Intensity-modulated radiotherapy and helical intensity-modulated radiotherapy (tomotherapy) are becoming widely used. The present study compared three-dimensional conformal radiotherapy, intensity-modulated radiotherapy and tomotherapy in terms of target coverage and preservation of organs at risk. METHODS: Ten patients treated with three-dimensional conformal radiotherapy, with a target volume close to or superimposed to the organs at risk, were retrospectively selected. The plans were re-planned with step-and-shoot 3/5 fields intensity-modulated radiotherapy and tomotherapy. Target coverage and sparing of organs at risk were statistically compared. RESULTS: Mean planning target volume V95% improved with sophisticated techniques (87.2%, 93.2%, 97.6% with three-dimensional conformal radiotherapy, intensity-modulated radiotherapy and tomotherapy, respectively). The comparison of three-dimensional conformal radiotherapy and intensity-modulated radiotherapy did not show significant differences, whereas differences were significant when three-dimensional conformal radiotherapy and tomotherapy as well as intensity-modulated radiotherapy and tomotherapy were compared. Mean planning target volume/clinical target volume D99-D98-D95 were not different between three-dimensional conformal radiotherapy and intensity-modulated radiotherapy, but they were different between tomotherapy and three-dimensional conformal radiotherapy and intensity-modulated radiotherapy, with better clinical target volume/and planning target volume coverage with the tomotherapy plans. Brain D33/66 were 31.1/11.8 Gy, 37.5/18.3 Gy and 28.5/14.7 Gy with three-dimensional conformal radiotherapy, intensity-modulated radiotherapy and tomotherapy, respectively. Mean brainstem, optic nerves and chiasma Dmax were always within the defined constraints. The homogeneity index improved with intensity-modulated radiotherapy/tomotherapy compared to three-dimensional conformal radiotherapy. Tomotherapy was better than intensity-modulated radiotherapy in all patients. CONCLUSIONS: In this selected group of patients, a significant dosimetric advantage was evident for tomotherapy compared with three-dimensional conformal radiotherapy and intensity-modulated radiotherapy. Significant advantages were evident in terms of panning target volume coverage (V95), D99, D98 and D95. The clinical significance of the results should be defined.


Assuntos
Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Radioterapia Conformacional/efeitos adversos , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/efeitos adversos , Radioterapia de Intensidade Modulada/métodos , Adulto , Idoso , Feminino , Humanos , Imageamento Tridimensional , Itália , Masculino , Pessoa de Meia-Idade , Radiometria , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Estudos Retrospectivos , Resultado do Tratamento
12.
Genetics ; 185(4): 1451-61, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20479146

RESUMO

The genomics revolution has spurred the undertaking of HapMap studies of numerous species, allowing for population genomics to increase the understanding of how selection has created genetic differences between subspecies populations. The objectives of this study were to (1) develop an approach to detect signatures of selection in subsets of phenotypically similar breeds of livestock by comparing single nucleotide polymorphism (SNP) diversity between the subset and a larger population, (2) verify this method in breeds selected for simply inherited traits, and (3) apply this method to the dairy breeds in the International Bovine HapMap (IBHM) study. The data consisted of genotypes for 32,689 SNPs of 497 animals from 19 breeds. For a given subset of breeds, the test statistic was the parametric composite log likelihood (CLL) of the differences in allelic frequencies between the subset and the IBHM for a sliding window of SNPs. The null distribution was obtained by calculating CLL for 50,000 random subsets (per chromosome) of individuals. The validity of this approach was confirmed by obtaining extremely large CLLs at the sites of causative variation for polled (BTA1) and black-coat-color (BTA18) phenotypes. Across the 30 bovine chromosomes, 699 putative selection signatures were detected. The largest CLL was on BTA6 and corresponded to KIT, which is responsible for the piebald phenotype present in four of the five dairy breeds. Potassium channel-related genes were at the site of the largest CLL on three chromosomes (BTA14, -16, and -25) whereas integrins (BTA18 and -19) and serine/arginine rich splicing factors (BTA20 and -23) each had the largest CLL on two chromosomes. On the basis of the results of this study, the application of population genomics to farm animals seems quite promising. Comparisons between breed groups have the potential to identify genomic regions influencing complex traits with no need for complex equipment and the collection of extensive phenotypic records and can contribute to the identification of candidate genes and to the understanding of the biological mechanisms controlling complex traits.


Assuntos
Cruzamento/métodos , Bovinos/genética , Haplótipos/genética , Leite/normas , Polimorfismo de Nucleotídeo Único , Algoritmos , Animais , Bovinos/metabolismo , Mapeamento Cromossômico , Cromossomos de Mamíferos/genética , Feminino , Loci Gênicos/genética , Masculino , Leite/metabolismo
13.
AJR Am J Roentgenol ; 189(4): 860-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17885057

RESUMO

OBJECTIVE: The purpose of this study was to compare the diagnostic accuracy of digital mammography with that of screen-film mammography in concurrent cohorts participating in the same population-based screening program. MATERIALS AND METHODS: In a retrospective study covering 2004-2005, we compared digital with screen-film mammography in two concurrent screening cohorts of women 50-69 years old participating in a screening program operated from mobile units. Each cohort had 14,385 participants matched by age and interpreting radiologist from all participants consecutively registered. We compared recall and cancer detection rates. RESULTS: The recall rate was higher for digital mammography (4.56% vs 3.96%, p = 0.01), particularly when clustered microcalcifications were the only finding (1.05% vs 0.41%, p = 10(-6)) and for younger women (50-59 vs 60-69 years, 5.12% vs 4.17%, p = 0.009). The higher recall rate for digital mammography was mainly evident at incidence screening. The recall rate due to poor technical quality was lower with digital mammography (0.27% vs 0.50%, p = 0.002), possibly because real-time feedback was available. The detection rate was higher for digital mammography (0.72% vs 0.58%, p = 0.14), particularly for cancers depicted as clustered microcalcifications (0.26% vs 0.12%, p = 0.007), in younger (50-59 years) women (0.63% vs 0.42%, p = 0.09), and in denser breasts (1.09% vs 0.53%, p = 0.24). No significant difference was observed in positive predictive value on recall for digital mammography or screen-film mammography. Early cancer (pTis, pT1mic, pT1a) was more frequent in cancer detected with digital mammography than in that detected with screen-film mammography (41.3% vs 27.3%, p = 0.06). CONCLUSION: Digital mammography may be more effective than screen-film mammography in contemporary screening practice in mobile units. The data indicate that digital mammography depicts more tumors than does screen-film mammography, especially lesions seen as microcalcifications. The potential association with improved outcome warrants further study.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia/instrumentação , Mamografia/métodos , Programas de Rastreamento/métodos , Intensificação de Imagem Radiográfica/métodos , Filme para Raios X , Idoso , Estudos de Coortes , Feminino , Humanos , Programas de Rastreamento/instrumentação , Pessoa de Meia-Idade , Intensificação de Imagem Radiográfica/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Plant Physiol ; 145(3): 933-45, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17827273

RESUMO

The Opaque2 (O2) basic leucine (Leu)-zipper transcriptional activator controls the expression of several genes in maize (Zea mays). We investigated the phosphorylation extent of wild-type O2 and mutant-defective or mutant-truncated o2 polypeptides in endosperm cells, their subcellular localization, participation in complex formation, and involvement in functional activity. Besides wild type, four mutant alleles (o2T, o2-52, o2It, and o2-676) producing o2 polypeptides and a null transcript allele (o2R) were considered. Observing the effects of these mutations, multiphosphorylation events in O2 or o2 proteins were confirmed and further investigated, and the involvement of both the nuclear localization signal (NLS)-B and Leu-zipper domains in proper targeting to the nucleus was ascertained. The absence of these domains in the o2T and o2It-S mutant-truncated forms holds them within the cytoplasm, where they are partially phosphorylated, whereas the presence of NLS-B and a partial Leu-zipper domain in o2-52 distributes this mutant-truncated form in both cytoplasm and nucleus. Although mutated in the NLS-B domain, the o2It-L and o2-676 mutant-defective forms are, respectively, partially or completely distributed into the nucleus. Only wild-type O2 and mutant-defective o2 polypeptides bearing the Leu-zipper are able to form complexes whose components were proven to bind the O2-zein target site by in vitro analyses. The transcription of a subset of H-zein genes as well as H-zein polypeptide accumulation in several o2-mutant-defective genotypes indicate the in vivo involvement of o2-mutant-defective proteins in O2-zein target site recognition. The gathered information broadens our knowledge on O2 functional activity and our view on possible quality protein maize trait manipulation or plant transformation via the utilization of cisgenic elements.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Zea mays/genética , Zea mays/metabolismo , Regulação da Expressão Gênica de Plantas , Mutação , Ligação Proteica , Isoformas de Proteínas , Transporte Proteico , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Transcrição Gênica , Zea mays/citologia , Zeína/genética , Zeína/metabolismo
15.
Eur J Radiol ; 55(2): 258-63, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16036157

RESUMO

PURPOSE: To compare the performance of screen-film and digital mammography in the assessment of screen-detected breast lesions. MATERIALS AND METHODS: A series of 100 consecutive mammographic screen-detected lesions (65 masses, 6 architectural distortions, 29 microcalcifications) deserving diagnostic assessment and judged to have a low positive predictive value underwent screen-film mammography (SFM) and digital mammography by a Fuji computed radiography system (FCR) (double exposure, same view, without removing compression) of the corresponding breast. Three sets of images (SFM, hard copy and soft copy FCR) were read, blind of assessment outcome, by three experienced radiologists. For the three different imaging modalities a contrast-detail analysis, dose evaluation and diagnostic accuracy by means of ROC analysis were performed. At the end of the diagnostic workup all suspicious cases (20) underwent surgical biopsy and were histologically confirmed as cancers and the cases which were negative or benign at assessment (80) were followed up for a period of 12-20 months. During the follow-up period two more cases proved to be cancers at subsequent examinations. RESULTS: Contrast-detail analysis gives better image quality for FCR compared to SFM at the same delivered dose, whilst in ROC analysis the SFM (AUC 0.7158), hard copy FCR (AUC 0.7404) and soft copy FCR (AUC 0.7501) (chi(2)=1.30, p=0.5220) are equivalent. CONCLUSION: FCR has a diagnostic performance equivalent to SFM in the assessment of screen-detected lesions with a low positive predictive value for cancer and it may be safely included in routine screening practice.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mamografia/métodos , Distribuição de Qui-Quadrado , Feminino , Humanos , Imagens de Fantasmas , Valor Preditivo dos Testes , Curva ROC , Intensificação de Imagem Radiográfica/métodos , Sensibilidade e Especificidade
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