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1.
Pediatr Radiol ; 48(5): 680-685, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29427027

RESUMO

BACKGROUND: Cuboid fractures are rare, usually occult on initial radiographs and are often underdiagnosed. MRI is more sensitive than radiographs for detecting acute, non-displaced cuboid fractures in adults, but only case reports have described these findings in children. OBJECTIVE: To summarize the MR and clinical features of cuboid fractures and compare MR findings with initial and follow-up radiographs in a cohort of children. MATERIALS AND METHODS: A retrospective search for patients <18 years of age with cuboid fractures was performed during a 10-year period at a large tertiary children's hospital. Subjects with cuboid fractures reported on MRI and available clinical history were included. MR images were evaluated for fracture location, fracture morphology, percentage of marrow edema in the cuboid, subchondral disruption, and associated tendon or ligamentous injury. Initial and short-term follow-up radiographs were also reviewed when available. RESULTS: Nineteen children ages 18 months to 17 years (mean: 9.0 years, standard deviation: 4.1 years, 63% boys) were diagnosed with cuboid fractures by MRI. Most cases of cuboid fractures are related to acute trauma (63%) but can be seen as stress fractures (16%). Most fractures (17/19, 89%) were linear in configuration. Fractures were most commonly adjacent to the tarsometatarsal joint (10/19, 52%). The degree of marrow edema was variable. Ligamentous injury was seen in two patients and tendon pathology was seen in one, all adolescents. Initial radiographs (n=10) were negative in 9 cases (90%). All available follow-up radiographs (n=12, obtained 19-42 days after MRI) demonstrated sclerosis in the region of the fracture. CONCLUSION: MR-depicted cuboid fractures in children typically occur in isolation. The fractures were most commonly adjacent to the tarsometatarsal joint and linear in morphology. Initial radiographs were usually normal and follow-up radiographs depicted sclerosis at the site of fracture in all available cases.


Assuntos
Traumatismos do Pé/diagnóstico por imagem , Fraturas Ósseas/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Ossos do Tarso/lesões , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos
2.
Pediatr Radiol ; 47(1): 104-107, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27717995

RESUMO

An 8-year-old girl presented with bilateral breast masses and was subsequently diagnosed with juvenile myelomonocytic leukemia. Juvenile myelomonocytic leukemia is a rare myelodysplastic syndrome that typically presents in boys younger than 3 years of age with splenomegaly, lymphadenopathy and skin findings. Bilateral breast masses in a child are rare and, as such, present a diagnostic dilemma due to the relative paucity of cases in the literature. We present a case of granulocytic sarcoma of the breasts in a patient with juvenile myelomonocytic leukemia. The authors hope that increased reporting and research regarding pediatric breast masses will help create awareness for such cases.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Leucemia Mielomonocítica Juvenil/diagnóstico por imagem , Neoplasias da Mama/terapia , Criança , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Leucemia Mielomonocítica Juvenil/terapia , Imageamento por Ressonância Magnética , Ultrassonografia Mamária
3.
Radiographics ; 36(6): 1807-1827, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27726754

RESUMO

With increasing participation and intensity of training in youth sports in the United States, the incidence of sports-related injuries is increasing, and the types of injuries are shifting. In this article, the authors review sports injuries of the lower extremity, including both acute and overuse injuries, that are common in or specific to the pediatric population. Common traumatic injuries that occur in individuals of all ages (eg, tears of the acetabular labrum and anterior cruciate ligament) are not addressed, although these occur routinely in pediatric sports. However, some injuries that occur almost exclusively in high-level athletes (eg, athletic pubalgia) are reviewed to increase awareness and understanding of these entities among pediatric radiologists who may not be familiar with them and thus may not look for them. Injuries are described according to their location (ie, hip, knee, or foot and ankle) and pathologic process (eg, apophysitis, osteochondritis dissecans). Examples of abnormalities and normal variants of the anatomy that are often misdiagnosed are provided. The injuries reviewed represent a common and growing subset of pathologic processes about which all pediatric and musculoskeletal radiologists should be knowledgeable. Understanding physeal injury is especially important because missed diagnoses can lead to premature physeal closure and osteoarthritis. ©RSNA, 2016.


Assuntos
Traumatismos em Atletas/diagnóstico por imagem , Fraturas Ósseas/diagnóstico por imagem , Aumento da Imagem/métodos , Traumatismos da Perna/diagnóstico por imagem , Osteoartrite/diagnóstico por imagem , Lesões dos Tecidos Moles/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Diagnóstico Diferencial , Medicina Baseada em Evidências , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Posicionamento do Paciente/métodos , Ultrassonografia/métodos
4.
Pediatr Radiol ; 46(11): 1606-13, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27488507

RESUMO

BACKGROUND: Image processing plays an important role in optimizing image quality and radiation dose in projection radiography. Unfortunately commercial algorithms are black boxes that are often left at or near vendor default settings rather than being optimized. OBJECTIVE: We hypothesize that different commercial image-processing systems, when left at or near default settings, create significant differences in image quality. We further hypothesize that image-quality differences can be exploited to produce images of equivalent quality but lower radiation dose. MATERIALS AND METHODS: We used a portable radiography system to acquire images on a neonatal chest phantom and recorded the entrance surface air kerma (ESAK). We applied two image-processing systems (Optima XR220amx, by GE Healthcare, Waukesha, WI; and MUSICA(2) by Agfa HealthCare, Mortsel, Belgium) to the images. Seven observers (attending pediatric radiologists and radiology residents) independently assessed image quality using two methods: rating and matching. Image-quality ratings were independently assessed by each observer on a 10-point scale. Matching consisted of each observer matching GE-processed images and Agfa-processed images with equivalent image quality. A total of 210 rating tasks and 42 matching tasks were performed and effective dose was estimated. RESULTS: Median Agfa-processed image-quality ratings were higher than GE-processed ratings. Non-diagnostic ratings were seen over a wider range of doses for GE-processed images than for Agfa-processed images. During matching tasks, observers matched image quality between GE-processed images and Agfa-processed images acquired at a lower effective dose (11 ± 9 µSv; P < 0.0001). CONCLUSION: Image-processing methods significantly impact perceived image quality. These image-quality differences can be exploited to alter protocols and produce images of equivalent image quality but lower doses. Those purchasing projection radiography systems or third-party image-processing software should be aware that image processing can significantly impact image quality when settings are left near default values.


Assuntos
Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Radiografia Torácica/métodos , Algoritmos , Humanos , Recém-Nascido , Pneumopatias/diagnóstico por imagem , Imagens de Fantasmas , Ecrans Intensificadores para Raios X
5.
Pediatr Radiol ; 45(11): 1706-11, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26008871

RESUMO

BACKGROUND: Cranial ultrasound is an essential screening and diagnostic tool in the care of neonates and is especially useful in the premature population for evaluation of potential germinal matrix/intraventricular hemorrhage (GM/IVH). There are typically two screening examinations, with the initial cranial sonography performed between 3 days and 14 days after birth, usually consisting of a series of static images plus several cinegraphic sweeps. OBJECTIVE: Our primary goal was to assess whether cinegraphic sweeps alone are as accurate for diagnosing neurological abnormalities as combined static and cinegraphic imaging in the initial cranial US evaluation of premature infants. Our secondary goal was to establish the difference in time required to perform these two examinations. MATERIALS AND METHODS: We retrospectively obtained 140 consecutive initial cranial US screening studies of premature infants. Three pediatric radiologists blinded to patient data read cinegraphic images alone and also combined (dual) imaging sets for a subset of subjects, recording findings for seven disease processes: germinal matrix/intraventricular hemorrhage (GM/IVH), right or left side; periventricular leukomalacia (PVL); choroid plexus cyst; subependymal cyst; cerebral and cerebellar infarction or hemorrhage; posterior fossa hemorrhage or infarction, and extra-axial hemorrhage. Separately, we compared retrospective dual imaging acquisition time against prospectively collected cinegraphic imaging time for premature infants undergoing initial cranial US evaluation. RESULTS: Equivalence testing demonstrated no difference in equivalency between initial cranial US screening using cinegraphic evaluation alone and dual imaging for GM/IVH, cerebral and cerebellar infarct or hemorrhage, and subependymal cyst (all P < 0.05). For PVL and choroid plexus cyst, cinegraphic imaging and dual imaging did not demonstrate equivalence (P > 0.05). Cinegraphic images were obtained in less than one-third of the time required for dual imaging. CONCLUSION: For the diagnoses that are critical to establish at initial screening (GM/IVH, cerebral and cerebellar infarct or hemorrhage) initial cranial US screening using cinegraphic sweeps was equivalent to dual imaging. Cinegraphic imaging required significantly less time to perform than dual imaging. We suggest that performance of cranial US screening using cinegraphic imaging alone is a potentially advantageous option in the initial evaluation of the premature neonate.


Assuntos
Encefalopatias/diagnóstico por imagem , Ecoencefalografia/métodos , Imagem Cinética por Ressonância Magnética/métodos , Nascimento Prematuro/diagnóstico por imagem , Feminino , Humanos , Recém-Nascido , Masculino , Variações Dependentes do Observador , Gravidez , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Gravação em Vídeo/métodos
10.
Int J Health Care Qual Assur ; 23(1): 110-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21387867

RESUMO

PURPOSE: This paper sets out to disseminate new knowledge about workforce planning, a crucial health sector issue. The Health Select Committee criticised NHS England's failure to develop and apply effective workforce planning. The Workforce Review Team (WRT) commissioned the Institute for Employment Research, Warwick University, to undertake a "rapid review" of global literature to identify good practice. A workforce planning overview, its theoretical principles, good practice exemplars are provided before discussing their application to healthcare. DESIGN/METHODOLOGY/APPROACH: The literature review, undertaken September-November 2007, determined the current workforce planning evidence within and outside health service provision and any consensus on successful workforce planning. FINDINGS: Much of the literature was descriptive and there was a lack of comparative or evaluative research-based evidence to inform U.K. healthcare workforce planning. Workforce planning practices were similar in other countries. PRACTICAL IMPLICATIONS: There was no evidence to challenge current WRT approaches to NHS England workforce planning. There are a number of indications about how this might be extended and improved, given additional resources. The evidence-base for workforce planning would be strengthened by robust and authoritative studies. ORIGINALITY/VALUE: Systematic workforce planning is a key healthcare quality management element. This review highlights useful information that can be turned into knowledge by informed application to the NHS. Best practice in other sectors and other countries appears to warrant exploration.


Assuntos
Planejamento em Saúde/organização & administração , Técnicas de Planejamento , Medicina Estatal/organização & administração , Benchmarking , Pessoal de Saúde/normas , Planejamento em Saúde/métodos , Humanos , Qualidade da Assistência à Saúde , Reino Unido
11.
Methods Mol Biol ; 1864: 3-18, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30415325

RESUMO

Efficient delivery of macromolecules into plant cells and tissues is important for both basic research and biotechnology product applications. In transgenic research, the goal is to deliver DNA molecules into regenerable cells and stably integrate them into the genome. Over the past 40 years, many macromolecule delivery methods have been studied. To generate transgenic plants, particle bombardment and Agrobacterium-mediated transformation are the methods of choice for DNA delivery. The rapid advance of genome editing technologies has generated new requirements on large biomolecule delivery and at the same time reinvigorated the development of new transformation technologies. Many of the gene delivery options that have been studied before are now being repurposed for delivering genome editing machinery for various applications. This article reviews the major progress in the development of tools for large biomolecule delivery into plant cells in the new era of precision genome engineering.


Assuntos
Edição de Genes/métodos , Técnicas de Transferência de Genes , Engenharia Genética/métodos , Genoma de Planta/genética , Agrobacterium/genética , Biotecnologia/instrumentação , Biotecnologia/métodos , Edição de Genes/instrumentação , Edição de Genes/tendências , Engenharia Genética/instrumentação , Engenharia Genética/tendências , Plantas Geneticamente Modificadas/genética , Transformação Genética
12.
Plant Biol (Stuttg) ; 9(3): 435-41, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17099844

RESUMO

Transcriptional gene silencing (TGS) is often associated with an increased level of cytosine methylation in the affected promoters. The effect of methylation of the cauliflower mosaic virus (CaMV) 35S promoter sequence on its binding to factors present in the nuclei was analyzed by electrophoretic mobility shift assays using extracts of petunia flowers. Specific DNA-protein interactions were detected in the region of the CaMV 35S promoter that contains the as-1 element and the region between - 345 and - 208. The binding of protein factor(s) to the as-1 element was influenced by cytosine methylation, whereas the binding to the region between - 345 and - 208 was unaffected. The results suggest that cytosine methylation of the as-1 element potentially affects the activity of the CaMV 35S promoter.


Assuntos
Citosina/metabolismo , Metilação de DNA , Vírus do Mosaico/genética , Proteínas Nucleares/metabolismo , Proteínas de Plantas/metabolismo , Regiões Promotoras Genéticas/genética , Sítios de Ligação , DNA-Citosina Metilases/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Petunia/genética , Petunia/metabolismo , Plantas Geneticamente Modificadas , Ligação Proteica
13.
Rev Argent Microbiol ; 39(1): 4-10, 2007.
Artigo em Espanhol | MEDLINE | ID: mdl-17585650

RESUMO

The aim of this work was to analyse a possible genome protection provided by a grape derivative (Tannat wine) in yeast cell populations exposed to H2O2. Haploid and diploid strains of Saccharomyces cerevisiae were used as eukaryotic model. Cell samples were exposed to H2O2 in a nutrient medium. Chromosomal DNA was analysed after isolation and separation by pulsed field electrophoresis. Double strand breaks were determined by laser densitometry and application of Poisson distribution. Both haploid and diploid cells showed H2O2 dose dependent DNA fractionation, as well as an increase of lethal -and mutation- events. Upon combination of the Tannat wine and H2O2 a significant decrease of double strand breaks was observed, in association with an increase in surviving fractions. No mutagenic effect was observed after wine exposure. Part of the observations regarding protective wine effect were simulated by exposure to high concentrations of alpha-tocopherol. Present results indicate that a grape derivative could act as a genome protector increasing cell survival probabilities. Among others, the involved molecular targets could be components of transduction redox cascades as well as DNA repair enzymes.


Assuntos
Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Vinho , Radicais Livres/metabolismo , Mutação , Vitis
14.
Tech Vasc Interv Radiol ; 20(4): 243-247, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29224656

RESUMO

Penetrating injuries can result in acute or subacute arterial injuries of the solid organs or extremities. Although most penetrating injuries are managed conservatively, some patients require endovascular or surgical treatment. Often, the best method for management is controversial and the level of urgency for clinical decision-making is high. Once the decision has been made to intervene, the operator must also determine the best embolization material and technique to use. Not unfrequently, these decisions are made during the course of the procedure. There are numerous embolization agents, each of which serves a very specific purpose, depending on the clinical scenario. Within this article, we will review endovascular treatment indications, contraindications, and endovascular techniques for the treatment of penetrating trauma of the solid organs or extremities.


Assuntos
Artérias/lesões , Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Extremidades/irrigação sanguínea , Radiografia Intervencionista , Lesões do Sistema Vascular/terapia , Ferimentos Penetrantes/terapia , Adulto , Angiografia Digital , Artérias/diagnóstico por imagem , Artérias/fisiopatologia , Angiografia por Tomografia Computadorizada , Embolização Terapêutica/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Humanos , Masculino , Resultado do Tratamento , Ultrassonografia Doppler em Cores , Lesões do Sistema Vascular/diagnóstico por imagem , Lesões do Sistema Vascular/fisiopatologia , Ferimentos Penetrantes/diagnóstico por imagem , Ferimentos Penetrantes/fisiopatologia , Adulto Jovem
15.
Tech Vasc Interv Radiol ; 20(4): 263-265, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29224659

RESUMO

Massive hemoptysis is a life-threatening condition often defined as coughing up 300-600mL of blood in 24 hours in an adult, or >8mL/kg in 24 hours in a child. Although the definition is controversial, one should view massive hemoptysis as any volume of expectorated blood that can cause respiratory failure. This is because mortality in the setting of hemoptysis is usually associated with asphyxiation, rather than exsanguination. Massive hemoptysis accounts for only about 5% of cases of hemoptysis, but when treated conservatively, has a reported mortality rate between 50% and 85%. Etiologies vary widely based on demographics. In children, infectious causes predominate in developing countries, and cystic fibrosis predominates among children of European descent. In adults, malignancy, bronchiectasis, and chronic infection are the most common causes. Treatment begins with resuscitation and airway protection, followed by minimally invasive bronchoscopic and endovascular techniques. Surgical interventions are considered last line therapy due to mortality rates of 37%-43% in the setting of massive hemoptysis. Bronchial artery embolization is now considered the treatment of choice for massive hemoptysis.


Assuntos
Embolização Terapêutica/métodos , Procedimentos Endovasculares/métodos , Hemoptise/terapia , Hemorragia/terapia , Radiografia Intervencionista , Adolescente , Angiografia , Artérias Brônquicas/diagnóstico por imagem , Artérias Brônquicas/fisiopatologia , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Hemoptise/diagnóstico por imagem , Hemoptise/etiologia , Hemoptise/mortalidade , Hemorragia/diagnóstico por imagem , Hemorragia/mortalidade , Hemorragia/fisiopatologia , Humanos , Masculino , Fatores de Risco , Resultado do Tratamento
16.
Spine (Phila Pa 1976) ; 42(7): E417-E424, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27513224

RESUMO

STUDY DESIGN: Retrospective consecutive cohort series. OBJECTIVE: The aim of this study was to develop a low-dose computed tomography (CT) protocol for use in robot-assisted pediatric spinal surgery. SUMMARY OF BACKGROUND DATA: CT scans are utilized preoperatively for preoperative planning, by navigation software during robot-assisted surgery, and postoperatively to assess surgical implant placement. Traditionally high radiation doses produced by CT scanning are a concern in the highly radiosensitive pediatric population. METHODS: We developed a low-dose protocol using phantom scans. A cohort of patients undergoing CT scanning using the low-dose protocol was collected. Further, a matching cohort of patients who underwent standard scanning was collected. Image quality was assessed by observer ratings. Radiation doses and image quality metrics were compared for the standard and low-dose protocol patients. RESULTS: Effective dose significantly decreased 84% to 91% depending on patient size and whether the scan was preoperative or postoperative. All scans were compatible with the navigation software. No clinically significant differences in image quality were observed between low-dose and standard patient cohorts. CONCLUSIONS: Task-based CT protocol optimization can produce acceptable image quality with dose comparable to standard two-view radiography. LEVEL OF EVIDENCE: 2.


Assuntos
Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Escoliose/diagnóstico por imagem , Escoliose/cirurgia , Tomografia Computadorizada por Raios X/métodos , Adolescente , Estudos de Coortes , Feminino , Humanos , Masculino , Imagens de Fantasmas , Estudos Retrospectivos
17.
Orthopedics ; 39(4): e810-3, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-27158826

RESUMO

A 50-year-old woman with a chronic polyarthropathy was seen by her orthopedist for long-standing back and shoulder and worsening hip pain. A lateral labral tear and chronic trochanteric bursitis were diagnosed on hip magnetic resonance imaging, which was otherwise unremarkable. Hip arthroscopy was performed revealing an unusual bluish-tinged femoral head articular surface. Computed tomography scans of the spine were also obtained.


Assuntos
Alcaptonúria/diagnóstico , Artropatias/diagnóstico por imagem , Alcaptonúria/complicações , Artralgia/etiologia , Artroscopia , Feminino , Humanos , Artropatias/etiologia , Artropatias/cirurgia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
18.
Biochim Biophys Acta ; 1260(3): 328-32, 1995 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-7873609

RESUMO

The mouse uromodulin cDNA sequence was sequenced. The predicted peptide sequence is 642 amino acids long and contains several modular components including four epidermal growth factor like repeats, one betaglycan-like domain (ZP domain), and a consensus sequence for attachment of a glycosyl-phosphatidyl-inositol anchor. An arginine-glycine-aspartate tripeptide reported for rat and human sequence is absent in the mouse. There are several potential sites for post-translational modification.


Assuntos
Mucoproteínas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar , Humanos , Camundongos , Dados de Sequência Molecular , Mucoproteínas/química , Mucoproteínas/urina , Ratos , Homologia de Sequência de Aminoácidos , Uromodulina
19.
J Clin Oncol ; 11(3): 408-14, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7680373

RESUMO

PURPOSE: This study was undertaken to define an escalated dose schedule of methotrexate, vinblastine, doxorubicin, and cisplatin (E-MVAC) with hematopoietic growth-factor support, to define the ability to deliver E-MVAC with recombinant human granulocyte colony-stimulating factor (rhG-CSF) on 21- and 14-day schedules, and to assess the ability of rhG-CSF to maintain dose-intensity over four cycles of chemotherapy. PATIENTS AND METHODS: Twenty-three patients with transitional-cell carcinoma of the urothelium received E-MVAC in a phase I investigation. Patients were treated on an every-21-day (n = 19) or every-14-day schedule of administration (n = 4), with rhG-CSF support. Delivered dose-intensity was calculated at the completion of four cycles of therapy relative to the planned administration of conventional MVAC (relative dose-intensity [RDI]). Peripheral-blood progenitor cell kinetics in these patients were studied prospectively. RESULTS: Overall, the delivered RDI was 33% higher than the previously reported delivered dose-intensity of MVAC without hematopoietic support (140% for doxorubicin, 51% for cisplatin). Dose-intensity was well maintained through three cycles of therapy, after which leukopenia and thrombocytopenia became dose-limiting. Sixty-nine percent of patients with measurable disease responded, four (25%) with complete remissions. In five patients treated beyond the maximally tolerated dose (MTD), a 50- to 200-fold increase in G-CSF, granulocyte-macrophage CSF (GM-CSF), and interleukin-3 (IL-3)-responsive peripheral-blood progenitor cells over baseline was observed after 9 days of rhG-CSF administration. CONCLUSION: These findings demonstrate the feasibility and limitations of dose intensification of M-VAC with rhG-CSF. While the overall impact of the increased drug administration can only be assessed in randomized comparisons, the results of the present trial suggest that escalations of the components of the four-drug regimen are unlikely to improve significantly the outcome for patients with advanced urothelial tract tumors.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células de Transição/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Neoplasias Urológicas/tratamento farmacológico , Adolescente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Doxorrubicina/administração & dosagem , Feminino , Humanos , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico , Resultado do Tratamento , Vimblastina/administração & dosagem
20.
J Mol Biol ; 204(3): 523-34, 1988 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-3225844

RESUMO

Cytosine methylation has been studied in wheat rRNA genes at nucleolar organizers displaying different activities. The methylation pattern within a specific multigene locus is influenced by the number and type of rRNA genes in other rDNA loci in the cell. One CCGG site 164 base-pairs upstream from the start of transcription is preferentially unmethylated in some genes. Dominant, very active loci have a higher proportion of rRNA genes with unmethylated cytosine residues in comparison with recessive and inactive loci. It is concluded that cytosine methylation in rDNA is regulated and that the methylation pattern correlates with the transcription potential of an rRNA gene.


Assuntos
Citosina/metabolismo , Região Organizadora do Nucléolo , RNA Ribossômico/metabolismo , Triticum , Sítios de Ligação , Regulação da Expressão Gênica , Genes , Metilação , Sequências Repetitivas de Ácido Nucleico , Mapeamento por Restrição
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