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1.
CA Cancer J Clin ; 69(5): 386-401, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31361333

RESUMO

Brachytherapy is a specific form of radiotherapy consisting of the precise placement of radioactive sources directly into or next to the tumor. This technique is indicated for patients affected by various types of cancers. It is an optimal tool for delivering very high doses to the tumor focally while minimizing the probability of normal tissue complications. Physicians from a wide range of specialties may be involved in either the referral to or the placement of brachytherapy. Many patients require brachytherapy as either primary treatment or as part of their oncologic care. On the basis of high-level evidence from randomized controlled trials, brachytherapy is mainly indicated: 1) as standard in combination with chemoradiation in patients with locally advanced cervical cancer; 2) in surgically treated patients with uterine endometrial cancer for decreasing the risk of vaginal vault recurrence; 3) in patients with high-risk prostate cancer to perform dose escalation and improve progression-free survival; and 4) in patients with breast cancer as adjuvant, accelerated partial breast irradiation or to boost the tumor bed. In this review, the authors discuss the clinical relevance of brachytherapy with a focus on indications, levels of evidence, and results in the overall context of radiation use for patients with cancer.


Assuntos
Braquiterapia/métodos , Quimiorradioterapia/métodos , Medicina Baseada em Evidências/métodos , Terapia Neoadjuvante/métodos , Neoplasias/terapia , Antineoplásicos/uso terapêutico , Progressão da Doença , Fracionamento da Dose de Radiação , Educação Médica Continuada , Humanos , Neoplasias/complicações , Neoplasias/mortalidade , Seleção de Pacientes , Médicos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
J Org Chem ; 89(7): 4733-4740, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38520355

RESUMO

Aggregation-induced emitting (AIE) luminophores are sensitive and easy-to-handle types of probes that allow driving a stimulus-responsive off/on optical tool through the manipulation of the aggregation behavior. In this work, tetraphenylethene (TPE)-phenylalanine derivatives, characterized by strong aggregation-induced luminescence, were obtained through Suzuki-Miyaura cross-coupling reactions. The reaction proved to be straightforwardly applicable in the single amino acid synthesis as well as in the late-stage peptide functionalization by means of both the classical solution-phase reaction and solid-phase synthesis. A comprehensive structural and analytical investigation highlighted the features driving the self-assembly process and its relationship to AIE efficiency. In particular, we showed that the simple slight (asymmetric) extension of the TPE π-systems results in more efficient and brighter emissions, with respect to the simple TPE system itself.

3.
Lancet ; 399(10336): 1695-1707, 2022 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-35405085

RESUMO

BACKGROUND: Current standard of care for metastatic castration-sensitive prostate cancer supplements androgen deprivation therapy with either docetaxel, second-generation hormonal therapy, or radiotherapy. We aimed to evaluate the efficacy and safety of abiraterone plus prednisone, with or without radiotherapy, in addition to standard of care. METHODS: We conducted an open-label, randomised, phase 3 study with a 2 × 2 factorial design (PEACE-1) at 77 hospitals across Belgium, France, Ireland, Italy, Romania, Spain, and Switzerland. Eligible patients were male, aged 18 years or older, with histologically confirmed or cytologically confirmed de novo metastatic prostate adenocarcinoma, and an Eastern Cooperative Oncology Group performance status of 0-1 (or 2 due to bone pain). Participants were randomly assigned (1:1:1:1) to standard of care (androgen deprivation therapy alone or with intravenous docetaxel 75 mg/m2 once every 3 weeks), standard of care plus radiotherapy, standard of care plus abiraterone (oral 1000 mg abiraterone once daily plus oral 5 mg prednisone twice daily), or standard of care plus radiotherapy plus abiraterone. Neither the investigators nor the patients were masked to treatment allocation. The coprimary endpoints were radiographic progression-free survival and overall survival. Abiraterone efficacy was first assessed in the overall population and then in the population who received androgen deprivation therapy with docetaxel as standard of care (population of interest). This study is ongoing and is registered with ClinicalTrials.gov, NCT01957436. FINDINGS: Between Nov 27, 2013, and Dec 20, 2018, 1173 patients were enrolled (one patient subsequently withdrew consent for analysis of his data) and assigned to receive standard of care (n=296), standard of care plus radiotherapy (n=293), standard of care plus abiraterone (n=292), or standard of care plus radiotherapy plus abiraterone (n=291). Median follow-up was 3·5 years (IQR 2·8-4·6) for radiographic progression-free survival and 4·4 years (3·5-5·4) for overall survival. Adjusted Cox regression modelling revealed no interaction between abiraterone and radiotherapy, enabling the pooled analysis of abiraterone efficacy. In the overall population, patients assigned to receive abiraterone (n=583) had longer radiographic progression-free survival (hazard ratio [HR] 0·54, 99·9% CI 0·41-0·71; p<0·0001) and overall survival (0·82, 95·1% CI 0·69-0·98; p=0·030) than patients who did not receive abiraterone (n=589). In the androgen deprivation therapy with docetaxel population (n=355 in both with abiraterone and without abiraterone groups), the HRs were consistent (radiographic progression-free survival 0·50, 99·9% CI 0·34-0·71; p<0·0001; overall survival 0·75, 95·1% CI 0·59-0·95; p=0·017). In the androgen deprivation therapy with docetaxel population, grade 3 or worse adverse events occurred in 217 (63%) of 347 patients who received abiraterone and 181 (52%) of 350 who did not; hypertension had the largest difference in occurrence (76 [22%] patients and 45 [13%], respectively). Addition of abiraterone to androgen deprivation therapy plus docetaxel did not increase the rates of neutropenia, febrile neutropenia, fatigue, or neuropathy compared with androgen deprivation therapy plus docetaxel alone. INTERPRETATION: Combining androgen deprivation therapy, docetaxel, and abiraterone in de novo metastatic castration-sensitive prostate cancer improved overall survival and radiographic progression-free survival with a modest increase in toxicity, mostly hypertension. This triplet therapy could become a standard of care for these patients. FUNDING: Janssen-Cilag, Ipsen, Sanofi, and the French Government.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias da Próstata , Antagonistas de Androgênios , Androgênios , Androstenos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Castração , Docetaxel/uso terapêutico , Feminino , Humanos , Hipertensão/etiologia , Masculino , Prednisona/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia
4.
N Engl J Med ; 382(23): 2187-2196, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32469183

RESUMO

BACKGROUND: Injectable luteinizing hormone-releasing hormone agonists (e.g., leuprolide) are the standard agents for achieving androgen deprivation for prostate cancer despite the initial testosterone surge and delay in therapeutic effect. The efficacy and safety of relugolix, an oral gonadotropin-releasing hormone antagonist, as compared with those of leuprolide are not known. METHODS: In this phase 3 trial, we randomly assigned patients with advanced prostate cancer, in a 2:1 ratio, to receive relugolix (120 mg orally once daily) or leuprolide (injections every 3 months) for 48 weeks. The primary end point was sustained testosterone suppression to castrate levels (<50 ng per deciliter) through 48 weeks. Secondary end points included noninferiority with respect to the primary end point, castrate levels of testosterone on day 4, and profound castrate levels (<20 ng per deciliter) on day 15. Testosterone recovery was evaluated in a subgroup of patients. RESULTS: A total of 622 patients received relugolix and 308 received leuprolide. Of men who received relugolix, 96.7% (95% confidence interval [CI], 94.9 to 97.9) maintained castration through 48 weeks, as compared with 88.8% (95% CI, 84.6 to 91.8) of men receiving leuprolide. The difference of 7.9 percentage points (95% CI, 4.1 to 11.8) showed noninferiority and superiority of relugolix (P<0.001 for superiority). All other key secondary end points showed superiority of relugolix over leuprolide (P<0.001). The percentage of patients with castrate levels of testosterone on day 4 was 56.0% with relugolix and 0% with leuprolide. In the subgroup of 184 patients followed for testosterone recovery, the mean testosterone levels 90 days after treatment discontinuation were 288.4 ng per deciliter in the relugolix group and 58.6 ng per deciliter in the leuprolide group. Among all the patients, the incidence of major adverse cardiovascular events was 2.9% in the relugolix group and 6.2% in the leuprolide group (hazard ratio, 0.46; 95% CI, 0.24 to 0.88). CONCLUSIONS: In this trial involving men with advanced prostate cancer, relugolix achieved rapid, sustained suppression of testosterone levels that was superior to that with leuprolide, with a 54% lower risk of major adverse cardiovascular events. (Funded by Myovant Sciences; HERO ClinicalTrials.gov number, NCT03085095.).


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos Hormonais/uso terapêutico , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Leuprolida/uso terapêutico , Compostos de Fenilureia/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Pirimidinonas/uso terapêutico , Testosterona/sangue , Adenocarcinoma/sangue , Administração Oral , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Hormonais/efeitos adversos , Doenças Cardiovasculares/induzido quimicamente , Hormônio Liberador de Gonadotropina/agonistas , Humanos , Injeções Subcutâneas , Leuprolida/efeitos adversos , Masculino , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Neoplasias da Próstata/sangue , Pirimidinonas/efeitos adversos
5.
Chemistry ; 29(28): e202300339, 2023 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-36939032

RESUMO

Structure-property correlations in the thiahelicene family are often not trivial beacuse most of the functional groups present on the helical scaffold modify the conjugation size of the π-system. Selecting fluorine-containing groups to provide strong inductive effects without interacting with low-lying orbitals of the system could be the way to overcome the issue. Here we report a study on three fluorine-functionalized tetrathia[7]helicenes, highlighting interesting correlations between the position of the functional groups and the conjugated skeleton properties. Helicenes Heli-F2 and Heli-CF-F2 were prepared by photoinduced isomerization-electrocyclization (the Mallory photocyclization) of the corresponding fluorinated benzodithienyl-ethenes Alk-F2 and Alk-CF-F2, which were prepared in high yields through stereo-conservative Stille reaction. Notably these helicenes were found to display green phosphorescence around 530-550 nm, and the studies suggest an efficient spin-orbit coupling mechanism in these high-energy triplet nonplanar conjugated molecules. Both helicenes and their precursors were thoroughly characterized by means of optical and electrochemical measurements, while DFT calculations enable a rationale on their structure-property correlations to be defined.

6.
J Org Chem ; 88(20): 14283-14291, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37792665

RESUMO

Herein, we investigate the use of organic photocatalysts in the visible light-promoted ß-functionalization of carbonyl compounds. In particular, we studied the addition of aliphatic aldehydes to α,ß-unsaturated compounds (ß-Michael addition), and the reaction of cyclic ketones with either ketones (ß-aldol condensation) or imines (ß-Mannich reaction). Among the dyes tested, donor-acceptor cyanoarenes gave the best results, promoting the transformations of interest in moderate to good yields. The reaction scope was investigated on substrates with different steric and electronic properties. Fluorescence quenching analysis (Stern-Volmer experiments) led us to propose for these reactions a reductive quenching mechanism involving a transient 5πe- activation mode.

7.
Int J Urol ; 30(5): 437-445, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36746747

RESUMO

At present, surgery is still the gold standard for the local treatment of renal cancer. Nonetheless, in several clinical scenarios, stereotactic body radiation therapy (SBRT) also known as stereotactic ablative body radiotherapy (SABR) is emerging as a highly effective ablative technique in fragile patients and those with significant comorbidities, as well as in cases where percutaneous therapy (cryoablation or radiofrequency) is not viable. However, considering the intrinsic radioresistance of renal tumors, the optimal treatment schemes have not been established. In oligometastatic patients, it has been reported that the control of the oligometastases can be a potentially curable approach. Being a technique than can be administered exclusively or in combination with systemic therapy, treatment individualization based on patient characteristics is key. Another scenario under investigation is oligoprogression, where SBRT offers the possibility of delaying further lines of systemic therapy by eliminating subclones of resistant tumor with ablative doses, with the additional opportunity of stimulating the immune system (immunomodulatory role). In this review, we have conducted an analysis of recently published studies that test the role of this technique in different clinical scenarios of this disease. We have found promising results that make SBRT a potent therapeutic approach with low toxicity. We also comment on ongoing studies that will generate the necessary evidence needed for the implementation of this technique in our daily clinical practice.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Radiocirurgia , Humanos , Radiocirurgia/efeitos adversos , Radiocirurgia/métodos , Carcinoma de Células Renais/radioterapia , Carcinoma de Células Renais/cirurgia , Neoplasias Renais/radioterapia , Neoplasias Renais/cirurgia
8.
Phys Chem Chem Phys ; 24(22): 13616-13624, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35616431

RESUMO

Hybrid sp-sp2 structures can be efficiently obtained on metal substrates via on-surface synthesis. The choice of both the precursor and the substrate impacts on the effectiveness of the process and the stability of the formed structures. Here we demonstrate that using anthracene-based precursor molecules on Au(111) the formation of polymers hosting sp carbon chains is affected by the steric hindrance between aromatic groups. In particular, by scanning tunneling microscopy experiments and density functional theory simulations we show that the de-metalation of organometallic structures induces a lateral separation of adjacent polymers that prevents the formation of ordered domains. This study contributes to the understanding of the mechanisms driving the on-surface synthesis processes, a fundamental step toward the realization of novel carbon-based nanostructures with perspective applications in nanocatalysis, photoconversion, and nano-electronics.

9.
Phys Chem Chem Phys ; 24(28): 17077-17087, 2022 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-35792072

RESUMO

Stabilizing ordered assemblies of molecules represents the first step towards the construction of molecular devices featuring hybrid (organic-inorganic) interfaces where molecules can be easily functionalized in view of specific applications. Molecular layers of planar metal-tetraphenylporphyrins (MTPP) grown on an ultrathin iron oxide [namely Fe(001)-p(1 × 1)O] show indeed a high degree of structural order. The generality of such a picture is tested by exploiting non-planar porphyrins, such as vanadyl-TPP (VOTPP). These molecules feature a VO2+ ion in their center, with the O atom protruding out of the plane of the porphyrin ring. In this work, by employing diffraction, photoemission and X-ray absorption, we prove that non-planar VOTPP can nevertheless form a square and ordered superstructure, where porphyrin molecules lie flat with respect to the underlying substrate. Ab initio density functional theory simulations are used to elucidate the VO bond orientation with respect to the iron substrate.

10.
Lancet Oncol ; 22(8): e348-e357, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34339655

RESUMO

In patients with prostate cancer who have a high risk of pelvic nodal disease, the use of elective whole pelvis radiotherapy is still controversial. Two large, randomised, controlled trials (RTOG 9413 and GETUG-01) did not show a benefit of elective whole pelvis radiotherapy over prostate-only radiotherapy. In 2020, the POP-RT trial established the role of elective whole pelvis radiotherapy in patients who have more than a 35% risk of lymph node invasion (known as the Roach formula). POP-RT stressed the importance of patient selection. In patients with cN1 (clinically node positive) disease or pN1 (pathologically node positive) disease, the addition of whole pelvis radiotherapy to androgen deprivation therapy significantly improved survival compared with androgen deprivation therapy alone, as shown in large, retrospective studies. This patient population might increase in the future because use of the more sensitive prostate-specific membrane antigen PET-CT will become the standard staging procedure. Additionally, the SPORTT trial suggested a benefit of whole pelvis radiotherapy in biochemical recurrence-free survival in the salvage setting. A correct definition of the upper field border, which should include the bifurcation of the abdominal aorta, is key in the use of pelvic radiotherapy. As a result of using modern radiotherapy technology, severe late urinary and intestinal toxic effects are rare and do not seem to increase compared with prostate-only radiotherapy.


Assuntos
Metástase Linfática/radioterapia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Humanos , Masculino
11.
Nano Lett ; 19(8): 5537-5543, 2019 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-31295407

RESUMO

Porphyrins are an extremely valuable class of molecules engaged in a variety of roles spanning from biology to optoelectronics. Manipulation of the chemical and physical properties of the inner cavity of porphyrins has been recognized as crucial for the exploitation of these systems in organic devices, particularly when porphyrins self-organize at the interface with a flat-on orientation of the macrocycle. Such an orientation has been mostly observed on metallic surfaces. Unfortunately, the physical-chemical properties of the molecules result in being largely perturbed due to the molecule-metal interaction. In addition, conducting substrates are unsuited to exploit electrically driven devices based on organic layers. To overcome these issues, we performed a topology-based analysis of insulating organic single crystal structures to identify a surface which (i) ensures easy exfoliation through mechanical methods, (ii) ensures epitaxial match with an overlayer of close-packed flat-on porphyrin molecules, and (iii) displays chirality. The outcome of this work is represented by a unique crystal of mixed 2,5-diketopiperazine and fumaric acid in a 1:1 ratio. We demonstrate that the (110) surface of this crystal fulfills the aforementioned requirements and, thanks to its peculiar subnanometric corrugations, allows one to grow uniaxially aligned monolayers of flat-on porphyrin molecules assembled through van der Waals interactions.

13.
Photochem Photobiol Sci ; 17(9): 1169-1178, 2018 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-30047955

RESUMO

ß-Diketones are an important class of bidentate cyclometalating compounds, used in organometallic chemistry as ancillary ligands because of their wide commercial availability and easy synthesis. They are employed to finely tune the electronic, spectroscopic and physical properties of metal complexes. Heteroleptic iridium complexes often benefit from the use of ß-diketonate ligands, their properties being similar to those of the corresponding homoleptic tris-cyclometalated ones. Nevertheless, in some cases, their use results in a complete quenching of the phosphorescence. Aiming to understand the origin of this drawback, we designed a suitable class of heteroleptic complexes and studied their thermal stability (DSC/TGA). We explored the effect of the ancillary ligand in a series of Ir(iii) complexes bearing 2-phenylpyridine (ppy) as a cyclometalated ligand and acac (acetylacetonate), tta (2-thienoyltrifluoroacetonate), dtdk (1,3-di(thiophen-2-yl)propane-1,3-dionate) and BPhen (4,7-diphenyl-1,10-phenanthroline) as ancillary ligands. Through photochemical and electrochemical investigations, whose results agree with and support our density functional theory calculations, we demonstrate that ß-diketonate ligands with low triplet energy generate dark triplet excited states with negligible coupling to the ground state which indeed promote non-radiative relaxation through population of higher states.

14.
Prostate ; 77(10): 1160-1166, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28594087

RESUMO

INTRODUCTION: Adult prostatic sarcoma (PS) is a rare disease. While surgery is considered the standard approach, the role of other therapies is not completely established. We report results of the largest multicentric contemporary cohort of PS patients. MATERIALS AND METHODS: This study included 61 adult PS patients treated in 16 American and European Institutions. Median age was 64.4 years (range: 22-87). Curative surgery was delivered in 48 patients (prostatectomy = 26, cystoprostatectomy = 22), usually with lymphadenectomy (n = 40). Curative radiotherapy (RT) was delivered in 32 patients, as radical (n = 5), neoadjuvant (n = 10), or postoperative treatment (n = 17). Eighteen patients received chemotherapy. None of the patients received hormonal therapy. RESULTS: Median follow-up was 72 months (95%CI: 55-not reached). Five-year local control (LC), overall survival (OS), cancer-specific survival, disease-free survival, and metastases-free rates were 47%, 53%, 56%, 35%, and 35%, respectively. Notably, curative RT (neoadjuvant, adjuvant, or definitive) was associated with improved 5-year LC (55% vs. 31%, P = 0.02) and OS (59% vs. 46%, P = 0.1). Surgically treated patients presenting with a cT3-4 tumor (n = 31), who received RT (n = 24), had a significantly improved 5-year LC (68% vs, 33%, P = 0.004) and OS (65% vs. 21%, P < 0.001) rates compared to patients not receiving RT. cT4 patients demonstrated a significantly lower 5-year OS (43% vs. 61%, P = 0.006) and LC (29% vs. 69%, P < 0.001) rates. Histologic subtype was not associated with LC and OS, but patients with prostatic stromal sarcoma, rhabdomyosarcoma, or sarcomatoid carcinoma had worse 5-year LC compared to other types (47% vs. 55%) and OS (49% vs. 58%). CONCLUSION: Adult PS has a poor prognosis. Locally advanced tumors have poor LC and OS rates. Curative RT should be considered part of the multidisciplinary approach to PS.


Assuntos
Antineoplásicos/uso terapêutico , Excisão de Linfonodo , Prostatectomia , Neoplasias da Próstata , Radioterapia , Sarcoma , Adulto , Idoso , Terapia Combinada/métodos , Terapia Combinada/estatística & dados numéricos , Humanos , Cooperação Internacional , Excisão de Linfonodo/métodos , Excisão de Linfonodo/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Próstata/patologia , Prostatectomia/métodos , Prostatectomia/estatística & dados numéricos , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia , Radioterapia/métodos , Radioterapia/estatística & dados numéricos , Doenças Raras/mortalidade , Doenças Raras/patologia , Doenças Raras/terapia , Sarcoma/mortalidade , Sarcoma/patologia , Sarcoma/terapia , Análise de Sobrevida
15.
J Urol ; 208(5): 1054-1055, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35947520
16.
Curr Opin Urol ; 27(6): 580-586, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28816713

RESUMO

PURPOSE OF REVIEW: Despite improvement in systemic treatment, the prognosis of men with de novo metastatic prostate cancer remains poor. Treating the local disease may not only reduce the occurrence of local urologic symptoms, but also slow the metastatic process, either by reducing the seeding from the primary tumor or by altering the microenvironment and thus minimizing the formation of new metastatic sites. RECENT FINDINGS: Retrospective and population-based studies have suggested that the addition of local treatment to systemic therapy may improve survival in this patient group. The aim of this review is to discuss the biologic rationale of such an approach, present and discuss the current available evidence, with a focus on radiation-based treatments. It is key to also address the issue of patient selection as not all patients with metastatic prostate cancer will benefit from the treatment of the primary tumor. SUMMARY: Retrospective and population-based research suggests a survival benefit of prostatectomy or radiotherapy in metastatic prostate cancer patients. Clinical trials evaluating the role of prostate radiotherapy in the metastatic setting are ongoing.


Assuntos
Neoplasias da Próstata/radioterapia , Radioterapia , Humanos , Masculino , Prostatectomia , Neoplasias da Próstata/patologia
17.
Photochem Photobiol Sci ; 16(8): 1220-1229, 2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28677718

RESUMO

Iridium complexes bearing cyclometalated (C^N) ligands are the current emitters of choice for efficient phosphorescent organic light emitting diodes (OLEDs). Homoleptic iridium complexes Ir(C^N)3 and the analogous heteroleptic ones carrying a ß-diketonate ancillary ligand (C^N)2Ir(O^O) often exhibit similar photophysical properties and device performances; the choice among them usually depends both on the yield/ease of the respective synthetic preparations as well as on the device fabrication methods (i.e. vacuum-deposition or solution-process). In our recent study we found a significant spectral red shift on going from the homoleptic to the ß-diketonate Ir(iii) derivatives. The NIR emitting complex Ir(iqbt)2dpm (λmax = 710 nm) has almost 20 nm red shifted emission compared to the homologue Ir(iqbt)3 making only the former a real NIR emitter. For comparison, we studied the Pt(iqbt)dpm complex as the suitable example to investigate metal ligand interactions. Noteworthily the Pt(iqbt)dpm emission perfectly overlaps that of the Ir(iqbt)2dpm. In this paper we provide an in-depth investigation of these systems by electrochemical and spectroscopic analyses and corroborate the results with DFT and TDDFT calculations to investigate whether the Pt(ii) complex can be used as a model system to predict how far the emission can be pushed in a Ir(iii) heteroleptic derivative bearing the same C^N ligand.

18.
Bioorg Med Chem Lett ; 26(19): 4613-4619, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27578248

RESUMO

Dual action compounds (DACs) based on 4-substituted aza-bicyclo[5.3.0]decane Smac mimetic scaffolds (ABDs) linked to a Zn(2+)-chelating moiety (DPA, o-hydroxy, m-allyl, N-acyl (E)-phenylhydrazone) through their 10 position are reported and characterized. Their synthesis, their target affinity (XIAP BIR3, Zn(2+)) in cell-free assays, their pro-apoptotic effects and cytotoxicity in tumor cells with varying sensitivity to Smac mimetics are described. The results are interpreted to evaluate the influence of Zn(2+) chelators on cell-free potency and on cellular permeability of DACs, and to propose novel avenues towards more potent antitumoral DACs based on Smac mimetics and Zn(2+) chelation.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Quelantes/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/química , Proteínas Mitocondriais/química , Mimetismo Molecular , Zinco/química , Proteínas Reguladoras de Apoptose , Linhagem Celular Tumoral , Quelantes/química , Cromatografia Líquida de Alta Pressão , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Espectrofotometria Ultravioleta
19.
Angew Chem Int Ed Engl ; 55(8): 2714-8, 2016 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-26804423

RESUMO

Three NIR-emitting neutral Ir(III) complexes [Ir(iqbt)2 (dpm)] (1), [Ir(iqbt)2 (tta)] (2), and [Ir(iqbt)2 (dtdk)] (3) based on the 1-(benzo[b]thiophen-2-yl)-isoquinolinate (iqtb) were synthesized and characterized (dpm=2,2,6,6-tetramethyl-3,5-heptanedionate; tta=2-thienoyltrifluoroacetonate; dtdk=1,3-di(thiophen-2-yl)propane-1,3-dionate). The compounds emit between λ=680 and 850 nm with high luminescence quantum yields (up to 16 %). By combining electrochemistry, photophysical measurements, and computational modelling, the relationship between the structure, energy levels, and properties were investigated. NIR-emitting, solution-processed phosphorescent organic light-emitting devices (PHOLEDs) were fabricated using the complexes. The devices show remarkable external quantum efficiencies (above 3 % with 1) with negligible efficiency roll-off values, exceeding the highest reported values for solution-processible NIR emitters.

20.
Curr Oncol Rep ; 17(12): 53, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26449841

RESUMO

A non-negligible proportion of prostate cancer (PCa) patients undergoing radical prostatectomy (RP) harbors aggressive disease. These individuals are at higher risk of experiencing recurrence after surgery. Results from prospective, randomized trials support the efficacy of adjuvant radiotherapy (aRT) on cancer control in selected patients with adverse disease features at RP. However, only one of these randomized trials found a significant benefit of aRT on survival. Although such a level of evidence is not currently available for salvage RT, retrospective studies demonstrated that this approach leads to excellent outcomes if administered at the earliest sign of PSA recurrence. Prognostic models might help clinicians in identifying patients who would benefit the most from adjuvant and/or salvage RT. This individualized approach would allow sparing the risk of short- and long-term toxicity in a substantial proportion of patients. Nonetheless, results from randomized trials are still awaited to compare the efficacy of (early) salvage and aRT.


Assuntos
Recidiva Local de Neoplasia/radioterapia , Prostatectomia , Neoplasias da Próstata/radioterapia , Radioterapia Adjuvante/métodos , Humanos , Masculino , Recidiva Local de Neoplasia/cirurgia , Prostatectomia/métodos , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Terapia de Salvação/métodos
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