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1.
Nano Lett ; 17(11): 6606-6612, 2017 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-29052414

RESUMO

Electron emission by femtosecond laser pulses from individual Au nanorods is studied with a time-of-flight momentum resolving photoemission electron microscope (ToF k-PEEM). The Au nanorods adhere to a transparent indium-tin oxide substrate, allowing for illumination from the rear side at normal incidence. Localized plasmon polaritons are resonantly excited at 800 nm with 100 fs long pulses. The momentum distribution of emitted electrons reveals two distinct emission mechanisms: a coherent multiphoton photoemission process from the optically heated electron gas leads to an isotropic emission distribution. In contrast, an additional emission process resulting from the optical field enhancement at both ends of the nanorod leads to a strongly directional emission parallel to the nanorod's long axis. The relative intensity of both contributions can be controlled by the peak intensity of the incident light.

2.
Endocrinology ; 162(8)2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-33735382

RESUMO

Although incurable, the prognosis for patients with metastatic breast cancer (MBC) has considerably improved with the approvals of multiple targeted and cytotoxic therapies. For hormone receptor-positive (HR+), ie, estrogen receptor and progesterone receptor positive (ER+/PgR+) and human epidermal growth factor receptor-2 negative (ie, ERBB2 gene nonamplified or HER2-) MBC, current approved treatment options include palliative endocrine therapy (ET), cyclin-dependent kinase (CDK 4/6) inhibitors, mTOR inhibitors, and PI3 kinase inhibitors. Most treatments target ER+ disease regardless of PgR status. Although the presence of PgR is crucial for ER+ cell proliferation in both normal and malignant mammary tissue, currently, there are no approved treatments that specifically target PgR. Recent literature has demonstrated the potential of antiprogestins in the treatment of MBC both in preclinical and clinical studies. Antiprogestins, including selective PgR modulators (SPRMs) that act as PgR antagonists, are a promising class of therapeutics for overcoming endocrine resistance in patients who develop activating estrogen receptor 1 (ESR1) and phosphatidylinositol 3-kinase (PI3K) gene mutations after prior endocrine therapy. Herein, we summarize the role of PgR and antiprogestins in the treatment of MBC. Other aspects on the use of functional imaging, clinical trials incorporating novel antiprogestins, and potential treatment combinations to overcome endocrine resistance will be briefly discussed.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Receptores de Progesterona/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Ensaios Clínicos como Assunto , Humanos , Receptores de Progesterona/metabolismo
3.
Drug Saf ; 43(10): 1045-1055, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32594454

RESUMO

INTRODUCTION: Antiprogestins have demonstrated promising activity against breast and gynecological cancers, but liver-related safety concerns limited the advancement of this therapeutic class. Onapristone is a full progesterone receptor antagonist originally developed as an oral contraceptive and later evaluated in phase II studies for metastatic breast cancer. Because of liver enzyme elevations identified during clinical studies, further development was halted. Evaluation of antiprogestin pharmacology and pharmacokinetic data suggested that liver enzyme elevations might be related to off-target or metabolic effects associated with clinical drug exposure. OBJECTIVE: We explored whether the use of a pharmaceutic strategy targeting efficacious systemic dose concentrations, but with diminished peak serum concentrations and/or total drug exposure would mitigate hepatotoxicity. Twice-daily dosing of an extended-release formulation of onapristone was developed and clinically evaluated in light of renewed interest in antiprogestin therapy for treating progesterone receptor-positive breast and gynecologic cancers. The hepatotoxic potential of extended-release onapristone was assessed from two phase I-II studies involving patients with breast, ovarian, endometrial, and prostate cancer. RESULTS: Among the 88 patients in two phase I-II studies in progesterone receptor-positive malignancies treated with extended-release onapristone, elevated alanine aminotransferase/aspartate aminotransferase levels were found in 20% of patients with liver metastases compared with 6.3% without metastases. Of five patients with grade 3 or higher alanine aminotransferase elevations with or without bilirubin elevations (four with breast cancer and one with endometrial cancer), four were assessed as unrelated to extended-release onapristone by the safety data review committee. Furthermore, while the fifth patient's liver enzyme elevations were considered possibly drug related by the study investigator, they were adjudicated as unlikely to be related (< 25% likelihood) by a subsequent independent hepatologist. CONCLUSIONS: These results suggest that the extended-release formulation by reducing drug exposure may be associated with a reduced risk of hepatotoxicity, and supports the continued clinical evaluation of extended-release onapristone for treating progesterone receptor-positive cancers.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Gonanos/uso terapêutico , Antagonistas de Hormônios/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/tratamento farmacológico , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Preparações de Ação Retardada , Feminino , Neoplasias dos Genitais Femininos/tratamento farmacológico , Gonanos/administração & dosagem , Gonanos/efeitos adversos , Antagonistas de Hormônios/administração & dosagem , Antagonistas de Hormônios/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos/epidemiologia
4.
ACS Appl Mater Interfaces ; 8(38): 25476-88, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27598017

RESUMO

Porous organic-inorganic hybrid monoliths with hierarchical porosity exhibiting macro- and mesopores are prepared via sol-gel process under variation of the mesopore size. Organic moieties in the pore walls are incorporated by substituting up to 10% of the silicon precursor tetramethylorthosilicate with bisilylated benzene molecules. After functionalization with sulfonic acid groups, the resulting sulfonated hybrid monoliths featuring a bimodal pore structure are investigated regarding proton conduction depending on temperature and relative humidity. The hierarchical pore system and controlled mesopore design turn out to be crucial for sulfonation and proton conduction. These sulfonated hybrid hierarchical monoliths containing only 10% organic precursor exhibit higher proton conduction at different relative humidities than sulfonated periodic mesoporous organosilica made of 100% bisilylated precursors exhibiting solely mesopores, even with a lower concentration of sulfonic acid groups.

5.
ACS Appl Mater Interfaces ; 8(16): 10274-82, 2016 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-26867115

RESUMO

Nitrogen-rich carbon with both a turbostratic microstructure and meso/macroporosity was prepared by hard templating through pyrolysis of a tricyanomethanide-based ionic liquid in the voids of a silica monolith template. This multifunctional carbon not only is a promising anode candidate for long-life lithium-ion batteries but also shows favorable properties as anode and cathode host material owing to a high nitrogen content (>8% after carbonization at 900 °C). To demonstrate the latter, the hierarchical carbon was melt-infiltrated with sulfur as well as coated by atomic layer deposition (ALD) of anatase TiO2, both of which led to high-quality nanocomposites. TiO2 ALD increased the specific capacity of the carbon while maintaining high Coulombic efficiency and cycle life: the composite exhibited stable performance in lithium half-cells, with excellent recovery of low rate capacities after thousands of cycles at 5C. Lithium-sulfur batteries using the sulfur/carbon composite also showed good cyclability, with reversible capacities of ∼700 mA·h·g(-1) at C/5 and without obvious decay over several hundred cycles. The present results demonstrate that nitrogen-rich carbon with an interconnected multimodal pore structure is very versatile and can be used as both active and inactive electrode material in high-performance lithium-based batteries.

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