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1.
Contemp Clin Trials ; 142: 107564, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38704119

RESUMO

INTRODUCTION: Women with atypical hyperplasia (AH) or lobular carcinoma in situ (LCIS) have a significantly increased risk of breast cancer, which can be substantially reduced with antiestrogen therapy for chemoprevention. However, antiestrogen therapy for breast cancer risk reduction remains underutilized. Improving knowledge about breast cancer risk and chemoprevention among high-risk patients and their healthcare providers may enhance informed decision-making about this critical breast cancer risk reduction strategy. METHODS/DESIGN: We are conducting a cluster randomized controlled trial to evaluate the effectiveness and implementation of patient and provider decision support tools to improve informed choice about chemoprevention among women with AH or LCIS. We have cluster randomized 26 sites across the U.S. through the SWOG Cancer Research Network. A total of 415 patients and 200 healthcare providers are being recruited. They are assigned to standard educational materials alone or combined with the web-based decision support tools. Patient-reported and clinical outcomes are assessed at baseline, after a follow-up visit at 6 months, and yearly for 5 years. The primary outcome is chemoprevention informed choice after the follow-up visit. Secondary endpoints include other patient-reported outcomes, such as chemoprevention knowledge, decision conflict and regret, and self-reported chemoprevention usage. Barriers and facilitators to implementing decision support into clinic workflow are assessed through patient and provider interviews at baseline and mid-implementation. RESULTS/DISCUSSION: With this hybrid effectiveness/implementation study, we seek to evaluate if a multi-level intervention effectively promotes informed decision-making about chemoprevention and provide valuable insights on how the intervention is implemented in U.S. TRIAL REGISTRATION: NCT04496739.


Assuntos
Neoplasias da Mama , Quimioprevenção , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias da Mama/prevenção & controle , Quimioprevenção/métodos , Tomada de Decisões , Técnicas de Apoio para a Decisão , Antagonistas de Estrogênios/uso terapêutico , Antagonistas de Estrogênios/administração & dosagem , Conhecimentos, Atitudes e Prática em Saúde , Educação de Pacientes como Assunto/métodos , Medidas de Resultados Relatados pelo Paciente , Projetos de Pesquisa , Comportamento de Redução do Risco
2.
ESMO Open ; 7(4): 100526, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35780590

RESUMO

BACKGROUND: Tumor genomic profiling (TGP) often incidentally identifies germline pathogenic variants (PVs) associated with cancer predisposition syndromes. Methods used by somatic testing laboratories, including germline analysis, differ from designated germline laboratories that have optimized the identification of germline PVs. This study evaluated discrepancies between somatic and germline testing results, and their impact on patients. PATIENTS AND METHODS: Chart reviews were carried out at a single institution for patients who had both somatic and designated germline genetic testing. Cases with discrepant results in which germline PVs were not detected by the somatic laboratory or in which variant classification differed are summarized. RESULTS: TGP was carried out on 2811 cancer patients, 600 of whom also underwent designated germline genetic testing. Germline PVs were identified for 109 individuals. Discrepancies between germline genetic testing and tumor profiling reports were identified in 20 cases, including 14 PVs identified by designated germline genetic testing laboratories that were not reported by somatic testing laboratories and six variants with discrepant classifications between the designated germline and somatic testing laboratories. Three PVs identified by designated germline laboratories are targets for poly adenosine diphosphate-ribose polymerase (PARP) inhibitors and resulted in different treatment options. Of the PVs identified by designated germline laboratories, 60% (n = 12) were in genes with established associations to the patients' cancer, and 40% of the PVs were incidental. The majority (90%) of all discrepant findings, both contributory and incidental, changed management recommendations for these patients, highlighting the importance of comprehensive germline assessment. CONCLUSIONS: Methods used by somatic laboratories, regardless of the inclusion of germline analysis, differ from those of designated germline laboratories for identifying germline PVs. Unrecognized germline PVs may harm patients by missing hereditary syndromes and targeted therapy opportunities (e.g. anti-programmed cell death protein 1 immunotherapy, PARP inhibitors). Clinicians should refer patients who meet the criteria for genetic evaluation regardless of somatic testing outcomes.


Assuntos
Mutação em Linhagem Germinativa , Neoplasias , Predisposição Genética para Doença , Testes Genéticos , Genômica , Células Germinativas , Humanos
3.
Nanotechnology ; 32(15): 152001, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33412522

RESUMO

Silicene, the 2D silicon allotrope analogue of graphene, was theoretically predicted in 1994 as a metastable buckled honeycomb silicon monolayer. Similarly to its carbon counterpart it was predicted to present an electronic structure hosting Dirac cones. In the last decade a great deal of work has been done to synthesize silicene and exploit its properties. In this paper we will review our research group activity in the field, dealing in particular with silicon-substrate interaction upon silicon deposition, and discuss the still debated silicene formation starting from the chemistry of silicon unsaturated compounds.

4.
Sci Rep ; 10(1): 14619, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32884112

RESUMO

Topological surface states usually emerge at the boundary between a topological and a conventional insulator. Their precise physical character and spatial localization depend on the complex interplay between the chemical, structural and electronic properties of the two insulators in contact. Using a lattice-matched heterointerface of single and double bilayers of ß-antimonene and bismuth selenide, we perform a comprehensive experimental and theoretical study of the chiral surface states by means of microscopy and spectroscopic measurements complemented by first-principles calculations. We demonstrate that, although ß-antimonene is a trivial insulator in its free-standing form, it inherits the unique symmetry-protected spin texture from the substrate via a proximity effect that induces outward migration of the topological state. This "topologization" of ß-antimonene is found to be driven by the hybridization of the bands from either side of the interface.

5.
Nanotechnology ; 29(6): 065704, 2018 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-29320369

RESUMO

We report a study of the interface between antimony and the prototypical topological insulator Bi2Se3. Scanning tunnelling microscopy measurements show the presence of ordered domains displaying a perfect lattice match with bismuth selenide. Density functional theory calculations of the most stable atomic configurations demonstrate that the ordered domains can be attributed to stacks of ß-antimonene.

6.
J Phys Condens Matter ; 29(21): 215001, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28362270

RESUMO

The surface electronic structure of Si(1 1 1)-[Formula: see text] has been studied by angle-resolved photo electron spectroscopy. Replicas of the S 1 surface state are found in correspondence with several [Formula: see text] unit cells in the reciprocal space. This observation resolves in a direct way the long-standing dichotomy between the structural and electronic properties of the system previously discussed on the basis of the [Formula: see text] or [Formula: see text] R30° surface models.

7.
J Phys Condens Matter ; 25(31): 315301, 2013 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-23835457

RESUMO

Interest in the Si/Ag(110) system, which forms highly ordered linear nanostructures coined 'silicon nanoribbons', was recently boosted by the claim that such nanoribbons may be formed by silicon atoms arranged in a 2D honeycomb structure as in graphene, i.e. silicene. Despite such a revived interest, many discrepancies still exist in the recently reported results. This paper reports on a systematic investigation by scanning tunneling microscopy and low-energy electron diffraction of the Si/Ag(110) system as a function of the amount of deposited silicon and the deposition temperature. This reveals a complex interplay between these two factors, resulting in a rich array of possible self-assembled nanostructures and surface reconstructions. Several novel findings and clarification of the contradictory results reported in the literature are discussed in this work. In particular, the deposition temperature is demonstrated to be a key parameter to control the width of the Si nanoribbons produced. Recently, massive linear nanostructures were reported to be 'multilayer silicene', forming once the deposited silicon amount exceeds full coverage. However, we show that such nanostructures are also observed at low silicon coverage, demonstrating that their formation is exclusively determined by a deposition temperature higher than 460 K. On the other hand, for Si amounts higher than one monolayer the surface presents a novel c(8 × 4) reconstruction, which is responsible for the ×4 periodicity detected by LEED measurements, previously attributed to the 1.6 nm-wide nanoribbons overlayer or to 'multilayer silicene'. Finally, the large collection of acquired data also allowed us to single out image artifacts that may explain the contradictory results appearing in previous papers.

8.
Langmuir ; 27(12): 7410-8, 2011 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-21604683

RESUMO

The formation of 2D chiral monolayers obtained by self-assembly of chiral molecules on surfaces has been widely reported in the literature. Control of chirality transfer from a single molecule to surface superstructures is a challenging and important aspect for tailoring the properties of 2D nanostructures. However, despite the wealth of investigations performed in recent years, how chiral transfer takes place on a large scale still remains an open question. In this paper we report a coupling of scanning tunneling microscopy and low energy electron diffraction measurements with an original theoretical approach, combining molecular dynamics and essential dynamics with density functional theory, to investigate self-assembled chiral structures formed when alaninol adsorbs on Cu(100). The peculiarity of this system is related to the formation of tetrameric molecular structures which constitute the building blocks of the self-assembled chiral monolayer. Such characteristics make alaninol/Cu(100) a good candidate to reveal chiral expression changes. We find that the deposition of alaninol enantiomers results in the formation of isolated tetramers that are aligned along the directions of the substrate at low coverage or when geometrical confinement prevents long-range order. Conversely, a rotation of 14° with respect to the Cu(100) unit vectors is observed when small clusters of tetramers are formed. An insight to the process leading to a 2D globally chiral surface has been obtained by monitoring molecular assemblies as they grow from the early stages of adsorption, suggesting that the distinctive orientation of the self-assembled monolayer originates from a balance of cooperating forces which start acting only when tetramers pack together to form small clusters.

9.
Minerva Pediatr ; 62(2): 217-21, 2010 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-20440241

RESUMO

Infantile subglottic hemangioma is a pediatric tumor of endothelial cells characterized by an initial phase of rapid proliferation (around 6 months), followed by slow involution, often leading to complete regression following the first year of life. It is most frequently found in females and it usually it occurs also in the skin. From its position it can cause a progressive airway obstruction, so early diagnosis and treatment are very important. Many treatments have been described in the literature, including systemic steroids, intralesional steroid injection, carbon dioxide laser therapy, submucous resection, interferon alfa-2 and also tracheostomy as last approach. This case report discusses a 6-month old infant, that arrived to our attention for an acute two-way stridor. Laringoscopy under general anesthesia showed a subocclusive subglottic haemangioma that closed 70% of the laryngeal airway. In agreement with our ENT specialist it was decided to begin systemic steroid therapy, first by i.v. ingection during intensive therapy with rinotracheal intubation and mechanic ventilation; after the canula removal and the hemangioma reduction, the patient took oral steroids with a gradual reduction of the dose. This case evidences the importance of laryngoscopy in the diagnosis of subglottic haemangioma; it also proves the importance of multi-disciplinary collaboration with ENT specialist and dermatologist for the diagnosis and treatment of this kind of patient. It also shows that systemic steroids are an effective alternative in the management of obstructive pediatric subglottic hemangiomas.


Assuntos
Glote , Hemangioma/diagnóstico , Neoplasias Laríngeas/diagnóstico , Doença Aguda , Feminino , Hemangioma/complicações , Humanos , Lactente , Neoplasias Laríngeas/complicações , Sons Respiratórios/etiologia
10.
Phys Rev Lett ; 96(10): 106106, 2006 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-16605767

RESUMO

In order to provide a structural basis for a physical understanding of exchange bias in metal/magnetic-oxide interfaces, we have determined the structure of the Fe/NiO(001) interface by means of x-ray absorption spectroscopy and ab initio density functional theory calculations. A Fe-Ni alloyed phase on top of an interfacial FeO planar layer is formed. The FeO layer exhibits a 7% expanded interlayer distance and a 0.3 A buckling; its presence is predicted to increase the spin magnetic moment of the interface Fe atoms by 0.6 mu(B), compared to the ideally abrupt interface.

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