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1.
Am J Med Genet A ; 191(1): 299-305, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36286987

RESUMO

Informing parents that their child has a diagnosis of Down syndrome (DS) is a common example of the delivery of unexpected or difficult news. Expectations and life planning will change, and if detected prenatally, discussions might include the option of pregnancy termination. Medical school curricula currently include training in breaking unexpected news; however, it is difficult to teach and assess. We use the perspectives of clinicians, educators, and a medical student who is the parent of a child with DS to frame a discussion on teaching, practicing, and assessing communication of difficult news in human genetics during medical school.


Assuntos
Estudantes de Medicina , Criança , Humanos , Comunicação , Currículo , Relações Médico-Paciente , Revelação da Verdade
2.
Br J Neurosurg ; 37(2): 163-169, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34738491

RESUMO

OBJECTIVE: Unruptured intracranial aneurysms (UIA) are common. For many the treatment risks outweigh their risk of subarachnoid haemorrhage and patients undergo surveillance imaging. There is little data to inform if and how to monitor UIAs resulting in widely varying practices. This study aimed to determine the current practice of unruptured UIA surveillance in the United Kingdom. METHODS: A questionnaire was designed to address the themes of surveillance protocols for UIA including when surveillance is initiated, how frequently it is performed, and when it is terminated. Additionally, how aneurysm growth is managed and how clinically meaningful growth is defined were explored. The questionnaire was distributed to members of the British Neurovascular Group using probability-based cluster and non-probability purposive sampling methods. RESULTS: Responses were received from 30 of the 30 (100.0%) adult neurosurgical units in the United Kingdom of which 27 (90.0%) routinely perform surveillance for aneurysm growth. Only four units had a unit policy. The mean patient age up to which a unit would initiate follow-up of a low-risk UIA was 65.4 ± 9.0 years. The time points at which imaging is performed varied widely. There was an even split between whether units use a fixed duration of follow-up or an age threshold for terminating surveillance. Forty percent of units will follow-up patients more than 5 years from diagnosis. The magnitude in the change in size that was felt to constitute growth ranged from 1 to 3mm. No units routinely used vessel wall imaging although 27 had access to 3T MRI capable of performing it. CONCLUSIONS: There is marked heterogeneity in surveillance practices between units in the United Kingdom. This study will help units better understand their practice relative to their peers and provide a framework forplanning further research on aneurysm growth.


Assuntos
Aneurisma Intracraniano , Hemorragia Subaracnóidea , Adulto , Humanos , Pessoa de Meia-Idade , Idoso , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Seguimentos , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/epidemiologia , Hemorragia Subaracnóidea/cirurgia , Reino Unido , Inquéritos e Questionários
3.
Breast Cancer Res Treat ; 179(1): 67-77, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31562570

RESUMO

PURPOSE: Fulvestrant is a selective estrogen receptor downregulator (SERD) that is approved for first- or second-line use as a single agent or in combination with cyclin dependent kinase or phosphatidylinositol 3-kinase inhibitors for the treatment of metastatic breast cancer. Fulvestrant exhibits exceptionally effective antitumor activity in preclinical models of breast cancer, a success that has been attributed to its robust SERD activity despite modest receptor downregulation in patient tumors. By modeling human exposures in animal models we probe the absolute need for SERD activity. METHODS: Three xenograft models of endocrine therapy-resistant breast cancer were used to evaluate the efficacy of fulvestrant administered in doses historically used in preclinical studies in the field or by using a dose regimen intended to model clinical exposure levels. Pharmacokinetic and pharmacodynamic analyses were conducted to evaluate plasma exposure and intratumoral ER downregulation. RESULTS: A clinically relevant 25 mg/kg dose of fulvestrant exhibited antitumor efficacy comparable to the historically used 200 mg/kg dose, but at this lower dose it did not result in robust ER downregulation. Further, the antitumor efficacy of the lower dose of fulvestrant was comparable to that observed for other oral SERDs currently in development. CONCLUSION: The use of clinically unachievable exposure levels of fulvestrant as a benchmark in preclinical development of SERDs may negatively impact the selection of those molecules that are advanced for clinical development. Further, these studies suggest that antagonist efficacy, as opposed to SERD activity, is likely to be the primary driver of clinical response.


Assuntos
Antineoplásicos Hormonais/farmacocinética , Neoplasias da Mama/tratamento farmacológico , Antagonistas do Receptor de Estrogênio/farmacocinética , Fulvestranto/farmacocinética , Administração Oral , Animais , Antineoplásicos Hormonais/administração & dosagem , Relação Dose-Resposta a Droga , Antagonistas do Receptor de Estrogênio/administração & dosagem , Receptor alfa de Estrogênio/antagonistas & inibidores , Feminino , Fulvestranto/administração & dosagem , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Breast Cancer Res Treat ; 179(3): 769, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31734822

RESUMO

The article Pharmacokinetic and pharmacodynamic analysis of fulvestrant in preclinical models of breast cancer to assess the importance of its estrogen receptor-α degrader activity in antitumor efficacy, written by Suzanne E. Wardell, Alexander P. Yllanes, Christina A. Chao, Yeeun Bae, Kaitlyn J. Andreano, Taylor K. Desautels, Kendall A. Heetderks, Jeremy T. Blitzer, John D. Norris, Donald P. McDonnell, was originally published electronically on the publisher's internet portal on September 27, 2019 without open access. With the author(s)' decision to opt for Open Choice the copyright of the article changed on November 16, 2019 to © The Author(s) 2019 and the article is forthwith distributed under a Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The original article has been corrected.

5.
Breast Cancer Res Treat ; 180(3): 635-646, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32130619

RESUMO

PURPOSE: The combination of targeting the CDK4/6 and estrogen receptor (ER) signaling pathways with palbociclib and fulvestrant is a proven therapeutic strategy for the treatment of ER-positive breast cancer. However, the poor physicochemical properties of fulvestrant require monthly intramuscular injections to patients, which limit the pharmacokinetic and pharmacodynamic activity of the compound. Therefore, an orally available compound that more rapidly reaches steady state may lead to a better clinical response in patients. Here, we report the identification of G1T48, a novel orally bioavailable, non-steroidal small molecule antagonist of ER. METHODS: The pharmacological effects and the antineoplastic mechanism of action of G1T48 on tumors was evaluated using human breast cancer cells (in vitro) and xenograft efficacy models (in vivo). RESULTS: G1T48 is a potent and efficacious inhibitor of estrogen-mediated transcription and proliferation in ER-positive breast cancer cells, similar to the pure antiestrogen fulvestrant. In addition, G1T48 can effectively suppress ER activity in multiple models of endocrine therapy resistance including those harboring ER mutations and growth factor activation. In vivo, G1T48 has robust antitumor activity in a model of estrogen-dependent breast cancer (MCF7) and significantly inhibited the growth of tamoxifen-resistant (TamR), long-term estrogen-deprived (LTED) and patient-derived xenograft tumors with an increased response being observed with the combination of G1T48 and the CDK4/6 inhibitor lerociclib. CONCLUSIONS: These data show that G1T48 has the potential to be an efficacious oral antineoplastic agent in ER-positive breast cancer.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Neoplasias da Mama/tratamento farmacológico , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Anticorpos Anti-HIV/farmacologia , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Antagonistas de Estrogênios/farmacologia , Feminino , Humanos , Camundongos , Neoplasias Hormônio-Dependentes/metabolismo , Neoplasias Hormônio-Dependentes/patologia , Inibidores de Proteínas Quinases/farmacologia , Receptores de Estrogênio/metabolismo , Tamoxifeno/farmacologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Prostate ; 79(4): 414-424, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30560549

RESUMO

BACKGROUND: The recurrent p.Gly84Glu germline mutation (G84E) in HOXB13 is consistently associated with prostate cancer (PCa), although the mechanisms underlying such linkage remain elusive. The majority of the PCa-associated HOXB13 mutations identified are localized to two conserved domains in HOXB13 that have been shown to mediate the interaction with MEIS cofactors belonging to the TALE family of homeodomain transcription factors. In this study, we sought to interrogate the biochemical and functional interactions between HOXB13 and MEIS in prostatic cells with a goal of defining how the HOXB13-MEIS complex impacts PCa pathobiology and define the extent to which the oncogenic activity of G84E is related to its effect on HOXB13-MEIS interaction/function. METHODS: HOXB13 and MEIS paralog expression in prostate epithelial cells and PCa cell lines was characterized by qPCR and immunoblot analyses. HOXB13 and MEIS1 co-expression in human prostate tissue was confirmed by IHC, followed by co-IP mapping of HOXB13-MEIS1 interactions. Proliferation of the PCa cell line LAPC4 following shRNA-mediated knockdown of each gene or both genes was assessed using DNA- and metabolic-based assays. Transcriptional targets of HOXB13 and MEIS1 were identified by gene expression profiling and qPCR. Finally, protein stability of HOXB13 in the context of MEIS1 was determined using pulse-chase assays. RESULTS: HOXB13 and MEIS1 are co-expressed and interact in prostate cells. Both of the putative MEIS interacting domains (MID) within HOXB13 were shown to be capable of mediating the interaction between HOXB13 and MEIS1 independently and such interactions were not influenced by the G84E mutation. The inhibitory effect of either HOXB13 or MEIS1 knockdown on cellular proliferation was augmented by knockdown of both genes, and MEIS1 knockdown abolished HOXB13-driven regulation of BCHE and TNFSF10 mRNA expression. Notably, we demonstrated that MEIS1 stabilized the HOXB13 protein in LAPC4 cells. CONCLUSIONS: Our study provides evidence for functional HOXB13-MEIS1 interactions in PCa. MEIS1 may contribute to the cancer-promoting actions of HOXB13 in cellular proliferation and gene regulation by prolonging HOXB13 half-life. Our data demonstrates that G84E is not a loss-of-function mutation that interferes with HOXB13 stability or ability to interact with MEIS1.


Assuntos
Proteínas de Homeodomínio/metabolismo , Proteína Meis1/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Linhagem Celular Tumoral , Proliferação de Células , Expressão Gênica , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Mutação em Linhagem Germinativa , Proteínas de Homeodomínio/genética , Humanos , Masculino , Proteína Meis1/genética , RNA Mensageiro/análise
7.
Ann Bot ; 124(4): 591-604, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-30596965

RESUMO

BACKGROUND AND AIMS: Germplasm with diverse, agronomically relevant traits forms the foundation of a successful plant breeding programme. Since 1993, the United Nations has been advocating the implementation of the Convention on Biological Diversity (CBD) and the subsequent 2002 Bonn Guidelines as international best practice on germplasm collection and use. In 2006, a European team made an expedition to Asia to collect wild germplasm of Miscanthus, a C4 perennial rhizomatous grass, for breeding an environmentally adaptable, resilient and high-yielding bioenergy crop. We outline general aspects of germplasm collection, conservation, breeding and biomass production evaluation while following the CBD's guidelines, respecting biodiversity and conservation needs, and the ethical use of genetic resources. METHODS: Effective protocols, quarantine, methods for collecting seed and rhizomes, and a genebank for conservation were established. Versatile informatics and database architecture were used to assist in selection, flowering synchronization, crossing, evaluation, phenotyping and data integration. Approaches were formulated to comply with the CBD guidelines. KEY RESULTS: A total of 303 accessions of M. sinensis, M. sacchariflorus and M. floridulus were collected from 158 geographically and environmentally diverse locations. These species were shown to accumulate different amounts of aerial biomass due to combinations of stem count, height and thickness. Progeny from one interspecies cross accumulated more biomass in early trials and has shown double the yield performance in years 3-4 compared with the existing commercial cultivar M. × giganteus. An example of an F1 hybrid has already demonstrated the long-term potential of exploiting this collection for a breeding programme. CONCLUSIONS: By conforming to the CBD principles, the authors' international collaboration provides a practical example of implementing the CBD. The collection widened the genetic diversity of Miscanthus available to allow for breeding of novel hybrids that exhibit more diverse traits to increase yield and resilience for growth on marginal land and in climate-challenged environments.


Assuntos
Biodiversidade , Poaceae , Ásia , Europa (Continente) , Nações Unidas
8.
Nat Chem Biol ; 12(10): 795-801, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27501397

RESUMO

Clinical resistance to the second-generation antiandrogen enzalutamide in castration-resistant prostate cancer (CRPC), despite persistent androgen receptor (AR) activity in tumors, highlights an unmet medical need for next-generation antagonists. We have identified and characterized tetra-aryl cyclobutanes (CBs) as a new class of competitive AR antagonists that exhibit a unique mechanism of action. These CBs are structurally distinct from current antiandrogens (hydroxyflutamide, bicalutamide, and enzalutamide) and inhibit AR-mediated gene expression, cell proliferation, and tumor growth in several models of CRPC. Conformational profiling revealed that CBs stabilize an AR conformation resembling an unliganded receptor. Using a variety of techniques, it was determined that the AR-CB complex was not recruited to AR-regulated promoters and, like apo AR, remains sequestered in the cytoplasm, bound to heat shock proteins. Thus, we have identified third-generation AR antagonists whose unique mechanism of action suggests that they may have therapeutic potential in CRPC.


Assuntos
Antagonistas de Receptores de Andrógenos/farmacologia , Antineoplásicos/farmacologia , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/metabolismo , Antagonistas de Receptores de Andrógenos/química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/patologia , Relação Estrutura-Atividade
9.
Mol Cell ; 36(3): 405-16, 2009 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-19917249

RESUMO

HOXB13 is a member of the homeodomain family of sequence-specific transcription factors and, together with the androgen receptor (AR), plays a critical role in the normal development of the prostate gland. We demonstrate here that, in prostate cancer cells, HOXB13 is a key determinant of the response to androgens. Specifically, it was determined that HOXB13 interacts with the DNA-binding domain of AR and inhibits the transcription of genes that contain an androgen-response element (ARE). In contrast, the AR:HOXB13 complex confers androgen responsiveness to promoters that contain a specific HOXB13-response element. Further, HOXB13 and AR synergize to enhance the transcription of genes that contain a HOX element juxtaposed to an ARE. The profound effects of HOXB13 knockdown on androgen-regulated proliferation, migration, and lipogenesis in prostate cancer cells highlight the importance of the observed changes in gene expression.


Assuntos
Proteínas de Homeodomínio/metabolismo , Metribolona/farmacologia , Receptores Androgênicos/metabolismo , Sequência de Aminoácidos , Western Blotting , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Imunoprecipitação da Cromatina , Análise por Conglomerados , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Homeodomínio/genética , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Ligação Proteica/efeitos dos fármacos , RNA Interferente Pequeno/genética , Receptores Androgênicos/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Elementos de Resposta/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transfecção
10.
Angew Chem Int Ed Engl ; 54(33): 9659-62, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26083457

RESUMO

Androgen receptor (AR)-dependent transcription is a major driver of prostate tumor cell proliferation. Consequently, it is the target of several antitumor chemotherapeutic agents, including the AR antagonist MDV3100/enzalutamide. Recent studies have shown that a single AR mutation (F876L) converts MDV3100 action from an antagonist to an agonist. Here we describe the generation of a novel class of selective androgen receptor degraders (SARDs) to address this resistance mechanism. Molecules containing hydrophobic degrons linked to small-molecule AR ligands induce AR degradation, reduce expression of AR target genes and inhibit proliferation in androgen-dependent prostate cancer cell lines. These results suggest that selective AR degradation may be an effective therapeutic prostate tumor strategy in the context of AR mutations that confer resistance to second-generation AR antagonists.


Assuntos
Antagonistas de Receptores de Andrógenos/química , Antagonistas de Receptores de Andrógenos/farmacologia , Proteólise/efeitos dos fármacos , Receptores Androgênicos/metabolismo , Bibliotecas de Moléculas Pequenas/química , Bibliotecas de Moléculas Pequenas/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Benzamidas , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Nitrilas , Feniltioidantoína/análogos & derivados , Feniltioidantoína/química , Feniltioidantoína/farmacologia , Mutação Puntual , Próstata/efeitos dos fármacos , Próstata/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/genética
11.
Osiris ; 29: 35-48, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-26103746

RESUMO

The Sarepta, oder Bergpostill (1562) by Johann Mathesius is a book of sermons on mining and mineral subjects in which the composition and generation of metals in ore veins are discussed in terms of the sulfur-mercurius theory. Gur was an embodiment of mercurius or of sulfur and mercurius. Sulfur was evident in the sulfurous odor of the mines, in the supposed effects of subterranean heat, and in the deposition of mineral sulfur during the roasting of the ores. The toxic smoke given off during smelting was considered to be an additional manifestation of mercurius. Mathesius's sermons offer a glimpse of the ways miners' understanding of ores overlapped with alchemists' theories.


Assuntos
Alquimia , Mercúrio/história , Mineração/história , Enxofre/história , República Tcheca , História do Século XVI , Mercúrio/química , Prata , Enxofre/química
12.
Clin Cancer Res ; 30(6): 1152-1159, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38236581

RESUMO

PURPOSE: HOXB13 is an androgen receptor (AR) coregulator specifically expressed in cells of prostatic lineage. We sought to associate circulating tumor cell (CTC) HOXB13 expression with outcomes in men with mCRPC treated with abiraterone or enzalutamide. EXPERIMENTAL DESIGN: We conducted a retrospective analysis of the multicenter prospective PROPHECY trial of mCRPC men (NCT02269982, n = 118) treated with abiraterone/enzalutamide. CTC detection and HOXB13 complementary DNA (cDNA) expression was measured using a modified Adnatest, grouping patients into 3 categories: CTC 0 (undetectable); CTC+ HOXB13 CTC low (<4 copies); or CTC+ HOXB13 CTC high. The HOXB13 threshold was determined by maximally selected rank statistics for prognostic associations with overall survival (OS) and progression-free survival (PFS). RESULTS: We included 102 men with sufficient CTC HOXB13 cDNA, identifying 25%, 31%, and 44% of patients who were CTC 0, CTC+ HOXB13 low, and CTC+ HOXB13 high, respectively. Median OS were 25.7, 27.8, and 12.1 months whereas the median PFS were 9.0, 7.7, and 3.8 months, respectively. In subgroup analysis among men with CellSearch CTCs ≥5 copies/mL and adjusting for prior abi/enza treatment and Halabi clinical risk score, the multivariate HR for HOXB13 CTC detection was 2.39 (95% CI, 1.06-5.40) for OS and 2.78 (95% CI, 1.38-5.59) for PFS, respectively. Low HOXB13 CTC detection was associated with lower CTC PSA, PSMA, AR-FL, and AR-V7 detection, and more liver/lung metastases (41% vs. 25%). CONCLUSIONS: Higher CTC HOXB13 expression is associated with AR-dependent biomarkers in CTCs and is adversely prognostic in the context of potent AR inhibition in men with mCRPC.


Assuntos
Androstenos , Benzamidas , Células Neoplásicas Circulantes , Feniltioidantoína , Neoplasias de Próstata Resistentes à Castração , Masculino , Humanos , Células Neoplásicas Circulantes/patologia , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , RNA , Estudos Prospectivos , Estudos Retrospectivos , DNA Complementar/uso terapêutico , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Nitrilas/uso terapêutico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/uso terapêutico , Proteínas de Homeodomínio/genética
13.
J Exp Bot ; 64(2): 541-52, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23183254

RESUMO

Miscanthus sacchariflorus is a fast-growing C(4) perennial grass that can naturally hybridize with M. sinensis to produce interspecific hybrids, such as the sterile triploid M.× giganteus. The creation of such hybrids is essential for the rapid domestication of this novel bioenergy crop. However, progress has been hindered by poor understanding of the environmental cues promoting floral transition in M. sacchariflorus, which flowers less readily than M. sinensis. The purpose of this work was to identify the flowering requirements of M. sacchariflorus genotypes in order to expedite the introduction of new germplasm optimized to different environments. Six M. sacchariflorus accessions collected from a range of latitudes were grown under controlled photoperiod and temperature conditions, and flowering, biomass, and morphological phenotypic data were captured. Results indicated that M. sacchariflorus, irrespective of origin, is a quantitative short-day plant. Flowering under static long days (15.3h daylength), compared with shorter photoperiods, was delayed by an average 61 d, with an average associated increase of 52% of above-ground biomass (DM plant(-1)). Timing of floral initiation occurred between photoperiods of 14.2h and 12.1h, and accumulated temperatures of 553-1157 °C above a base temperature of 10 °C. Miscanthus sacchariflorus flowering phenology closely resembles that of Sorghum and Saccharum, indicating potentially similar floral pathways and suggesting that determination of the underlying genetic mechanisms will be facilitated by the syntenic relationships existing between these important C(4) grasses.


Assuntos
Flores/crescimento & desenvolvimento , Poaceae/genética , Biocombustíveis , Biomassa , Flores/genética , Flores/efeitos da radiação , Luz , Fotoperíodo , Poaceae/crescimento & desenvolvimento , Poaceae/efeitos da radiação , Temperatura
14.
J Neural Transm (Vienna) ; 120(2): 333-4, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23238975

RESUMO

There are no reliable data from randomised trials to decide whether anticoagulants or antiplatelet agents are better to prevent further thromboembolic events after cervical arterial dissection. Most neurologists favour anticoagulants based on the underlying pathology and the likely course of acute post-dissection thromboembolism.


Assuntos
Anticoagulantes/uso terapêutico , Dissecção Aórtica/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Humanos , Resultado do Tratamento
15.
Nature ; 450(7172): 1020-5, 2007 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-18075581

RESUMO

The halo of the Milky Way provides unique elemental abundance and kinematic information on the first objects to form in the Universe, and this information can be used to tightly constrain models of galaxy formation and evolution. Although the halo was once considered a single component, evidence for its dichotomy has slowly emerged in recent years from inspection of small samples of halo objects. Here we show that the halo is indeed clearly divisible into two broadly overlapping structural components--an inner and an outer halo--that exhibit different spatial density profiles, stellar orbits and stellar metallicities (abundances of elements heavier than helium). The inner halo has a modest net prograde rotation, whereas the outer halo exhibits a net retrograde rotation and a peak metallicity one-third that of the inner halo. These properties indicate that the individual halo components probably formed in fundamentally different ways, through successive dissipational (inner) and dissipationless (outer) mergers and tidal disruption of proto-Galactic clumps.

16.
Nature ; 477(7362): 37, 39, 2011 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-21886151
17.
Proc Natl Acad Sci U S A ; 106(29): 12178-83, 2009 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-19574450

RESUMO

The impact of ligand binding on nuclear receptor (NR) structure and the ability of target cells to distinguish between different receptor-ligand complexes are key determinants of the pharmacological activity of NR ligands. However, until relatively recently, these mechanistic insights have not been used in a prospective manner to develop screens for NR modulators with specific therapeutic activities. Driven by the need for unique androgen receptor (AR) antagonists that retain activity in hormone-refractory prostate cancer, we developed and applied a conformation-based screen to identify AR antagonists that were mechanistically distinct from existing drugs of this class. Two molecules were identified by using this approach, D36 and D80, which interact with AR in a unique manner and allosterically inhibit AR agonist activity. Unlike the clinically important antiandrogens, casodex and hydroxyflutamide, both D36 and D80 block androgen action in cellular models of hormone-refractory prostate cancer. Mechanistically, these compounds further distinguish themselves from classical AR antagonists in that they do not promote AR nuclear translocation and quantitatively inhibit the association of AR with DNA even under conditions of overexpression. Although the therapeutic potential of these antiandrogens is apparent, it is the demonstration that it is possible, to modulate the interaction of cofactors with agonist-activated AR, using second-site modulators, that has the greatest potential with respect to the therapeutic exploitation of AR and other NRs.


Assuntos
Antagonistas de Receptores de Andrógenos , Antineoplásicos/farmacologia , Neoplasias da Próstata/patologia , Regulação Alostérica/efeitos dos fármacos , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ligantes , Masculino , Camundongos , Conformação Molecular , Neoplasias da Próstata/genética , Receptores Androgênicos , Transcrição Gênica/efeitos dos fármacos
18.
Br J Neurosurg ; 26(3): 401-2, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22126232

RESUMO

A patient marked preoperatively for ulnar nerve decompression under general anaesthesia was found to have symmetrical operative site markings. The correct skin mark was transferred to the other side by her sleeping position the night before surgery. Skin marking is an adjunct to safe surgery but is not failsafe.


Assuntos
Descompressão Cirúrgica/efeitos adversos , Erros Médicos , Cuidados Pré-Operatórios/efeitos adversos , Ulna/inervação , Feminino , Humanos , Pessoa de Meia-Idade , Segurança do Paciente , Cuidados Pré-Operatórios/métodos , Pele , Tatuagem
19.
Orbit ; 31(1): 34-43, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22029716

RESUMO

PURPOSE: The purpose of this case series is to describe an orbito-cranial surgical approach for the management of optic nerve compression secondary to tumours extending into the optic canal. METHOD: We present a retrospective, observational case series of 4 patients who underwent surgery aimed at improving or stabilising vision for tumours invading the optic canal. In all cases tumours were not amenable to complete resection due to their intrinsic relation to important structures including: the internal carotid artery, cavernous sinus, optic and oculomotor nerves. All patients underwent combined orbito-cranial surgery consisting of craniotomy, debulking of the tumour, transcaruncular orbital and optic canal decompression with release of the dural sheath overlying the optic nerve via the craniotomy approach. Visual acuity was the primary outcome measure. RESULTS: Four patients, aged 42, 44, 61 and 78 years, three with spheno-orbital meningioma and one with cerebral sino-nasal adenocarcinoma were included in the study. Mean postoperative follow-up time was 26, 19 and 15.6 months. The fourth patient died at 2.9 months post-surgery due to high grade aggressive cerebral adenocarcinoma. Postoperative visual acuity improved by greater than 4 lines of Snellen acuity in 2 patients at 26 and 19.1 months. Two patients decreased from counting fingers vision to perception of light at last follow-up. CONCLUSIONS: In cases of non-resectable meningioma extending into the optic canal with secondary optic nerve compression, a combined surgical approach with optic canal decompression and dural sheath release may help preserve and even improve vision in certain cases.


Assuntos
Descompressão Cirúrgica/métodos , Síndromes de Compressão Nervosa/cirurgia , Doenças do Nervo Óptico/cirurgia , Neoplasias Orbitárias/complicações , Neoplasias dos Seios Paranasais/complicações , Adenocarcinoma/complicações , Adulto , Idoso , Humanos , Neoplasias Meníngeas/complicações , Meningioma/complicações , Pessoa de Meia-Idade , Síndromes de Compressão Nervosa/etiologia , Procedimentos Cirúrgicos Oftalmológicos/métodos , Doenças do Nervo Óptico/etiologia
20.
Cancer Lett ; 545: 215832, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35872263

RESUMO

Many patients with multiple myeloma (MM) have comorbidities and are treated with PPAR agonists. Immunomodulatory agents (IMiDs) are the cornerstones for MM therapy. Currently, little is known about how co-administration of PPAR agonists impacts lenalidomide treatment in patients with MM. Here, we determined the effects of PPAR agonists on anti-myeloma activities of lenalidomide in vitro and in a myeloma xenograft mouse model. Genetic overexpression and CRISPR/cas9 knockout experiments were performed to determine the role of CRBN in the PPAR-mediated pathway. A retrospective cohort study was performed to determine the correlation of PPAR expression with the outcomes of patients with MM. PPAR agonists down-regulated CRBN expression and reduced the anti-myeloma efficacy of lenalidomide in vitro and in vivo. Co-treatment with PPAR antagonists increased CRBN expression and improved sensitivity to lenalidomide. PPAR expression was higher in bone marrow cells of patients with newly diagnosed MM than in normal control bone marrow samples. High PPAR expression was correlated with poor clinical outcomes. Our study provides the first evidence that PPARs transcriptionally regulate CRBN and that drug-drug interactions between PPAR agonists and IMiDs may impact myeloma treatment outcomes.


Assuntos
Mieloma Múltiplo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Humanos , Lenalidomida/farmacologia , Camundongos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Peptídeo Hidrolases/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Estudos Retrospectivos , Ubiquitina-Proteína Ligases/metabolismo
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