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1.
iScience ; 25(5): 104184, 2022 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-35494220

RESUMO

The response of vital organs to different types of nutrition or diet is a fundamental question in physiology. We examined the cardiac response to 4 weeks of high-fat diet in mice, measuring cardiac metabolites and mRNA. Metabolomics showed dramatic differences after a high-fat diet, including increases in several acyl-carnitine species. The RNA-seq data showed changes consistent with adaptations to use more fatty acid as substrate and an increase in the antioxidant protein catalase. Changes in mRNA were correlated with changes in protein level for several highly responsive genes. We also found significant sex differences in both metabolomics and RNA-seq datasets, both at baseline and after high fat diet. This work reveals the response of a vital organ to dietary intervention at both metabolomic and transcriptomic levels, which is a fundamental question in physiology. This work also reveals significant sex differences in cardiac metabolites and gene expression.

2.
Adv Mater ; 34(1): e2102591, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34648198

RESUMO

Bimetallic Janus nanocrystals have received considerable interest in recent years owing to their unique properties and niche applications. The side-by-side distribution of two distinct metals provides a flexible platform for tailoring the optical and catalytic properties of nanocrystals. First, a brief introduction to the structural features of bimetallic Janus nanocrystals, followed by an extensive discussion of the synthetic approaches, is given. The strategies and experimental controls for achieving the Janus structure, as well as the mechanistic understandings, are specifically discussed. Then, a number of intriguing properties and applications enabled by the Janus nanocrystals are highlighted. Finally, this article is concluded with future directions and outlooks with respect to both syntheses and applications of this new class of functional nanomaterials.

3.
Inorg Chem ; 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33522790

RESUMO

Improving the performance of noble-metal nanocrystals in various applications critically depends on our ability to manipulate their synthesis in a rational, robust, and controllable fashion. Different from a conventional trial-and-error approach, the reduction kinetics of a colloidal synthesis has recently been demonstrated as a reliable knob for controlling the synthesis of noble-metal nanocrystals in a deterministic and predictable manner. Here we present a brief Viewpoint on the recent progress in leveraging reduction kinetics for controlling and predicting the outcome of a synthesis of noble-metal nanocrystals. With a focus on Pd nanocrystals, we first offer a discussion on the correlation between the initial reduction rate and the internal structure of the resultant seeds. The kinetic approaches for controlling both nucleation and growth in a one-pot setting are then introduced with an emphasis on manipulation of the reduction pathways taken by the precursor. We then illustrate how to extend the strategy into a bimetallic system for the preparation of nanocrystals with different shapes and elemental distributions. Finally, the influence of speciation of the precursor on reduction kinetics is highlighted, followed by our perspectives on the challenges and future endeavors in achieving a controllable and predictable synthesis of noble-metal nanocrystals.

4.
Angew Chem Int Ed Engl ; 60(22): 12192-12203, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33476449

RESUMO

In addition to the conventional knobs such as composition, size, shape, and defect structure, the crystal structure (or phase) of metal nanocrystals offers a new avenue for engineering their properties. Various strategies have recently been developed for the fabrication of colloidal metal nanocrystals in metastable phases different from their bulk counterparts. With a focus on noble metals, we begin with a brief introduction to their atomic packing, followed by a discussion about five major synthetic approaches to their colloidal nanocrystals in unconventional phases. We then highlight the success of synthesis in terms of mechanistic insights and experimental controls, as well as the enhanced catalytic properties. We end this Minireview with perspectives on the remaining issues and future opportunities.

5.
Chemistry ; 27(8): 2760-2766, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33152800

RESUMO

Noble-metal nanocrystals with anisotropic shapes have received increasing interest owing to their unique properties. Here, a facile route to the preparation of Pt nanobars with aspect ratios tunable up to 2.1 was reported by simply reducing a PtIV precursor in N,N-dimethylformamide (DMF) at 160 °C in the presence of poly(vinyl pyrrolidone) (PVP). In addition to its commonly observed roles as a solvent and a reductant, DMF could also decompose to generate CO, a capping agent capable of selectively passivating Pt{100} facets to promote the formation of nanobars. The size and aspect ratio of the nanobars could be tuned by varying the amount of PtIV precursor involved in the synthesis, as well as the concentration of PVP because of its dual roles as a stabilizer and a co-reductant. Our mechanistic study indicated that the anisotropic growth resulted from both particle coalescence and localized oxidative etching followed by preferential growth.

6.
Chem Rev ; 121(2): 649-735, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-32667792

RESUMO

The successful synthesis of noble-metal nanocrystals with controlled shapes offers many opportunities to not only maneuver their physicochemical properties but also optimize their figures of merit in a wide variety of applications. In particular, heterogeneous catalysis and surface science have benefited enormously from the availability of this new class of nanomaterials as the atomic structure presented on the surface of a nanocrystal is ultimately determined by its geometric shape. The immediate advantages may include significant enhancement in catalytic activity and/or selectivity and substantial reduction in materials cost while providing a well-defined model system for mechanistic study. With a focus on the monometallic system, this review article provides a comprehensive account of recent progress in the development of noble-metal nanocrystals with controlled shapes, in addition to their remarkable performance in a large number of catalytic and electrocatalytic reactions. We hope that this review article offers the impetus and roadmap for the development of next-generation catalysts vital to a broad range of industrial applications.

7.
Semin Reprod Med ; 38(1): 36-47, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-33152769

RESUMO

Intracytoplasmic sperm injection (ICSI) was first introduced as a supplemental method to conventional in vitro fertilization (c-IVF) for couples with severe male factor infertility to overcome the poor fertilization rate, while its indications expanded in current clinical practice and gained worldwide popularity. However, ICSI is invasive and crosses all natural barriers, raising several unresolved concerns regarding procedure-dependent and procedure-independent risks, as well as the characteristic of being labor-intensive and more expensive than c-IVF. This review is aimed to draw readers' attention, to the widespread use of ICSI worldwide, with its effectiveness in different indications of infertility, especially in those with unexplained infertility, as well as the cost-effectiveness of the ICSI-for-all strategy. Also, we covered current evidence on the short- and long-term safety of children born thanks to ICSI-aided conception. Further well-designed, adequately powered, and randomized controlled clinical trials are absolutely needed to arrive at a consensus on the use of ICSI over c-IVF in different populations.


Assuntos
Infertilidade Feminina/terapia , Infertilidade Masculina/terapia , Injeções de Esperma Intracitoplásmicas/métodos , Feminino , Fertilização/fisiologia , Humanos , Masculino , Gravidez , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas/efeitos adversos , Injeções de Esperma Intracitoplásmicas/economia
8.
J Immunother Cancer ; 7(1): 237, 2019 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-31484556

RESUMO

BACKGROUND: Preclinical evidence suggests that low-dose radiation may overcome the inhibitory effects of the tumor stroma and improve a tumor's response to immunotherapy, when combined with high-dose radiation to another tumor. The aim of this study was to evaluate tumor responses to this combination in a clinical setting. METHODS: A post-hoc analysis of 3 ongoing immunoradiation trials was performed. Twenty-six (of 155) patients received low-dose radiation (1-20 Gy total), either as scatter from high-dose radiation or from intentional treatment of a second isocenter with low-dose radiation, were evaluated for response. The low-dose lesions were compared to lesions that received no radiation (< 1 Gy total). Response rates, both defined as complete and partial responses as defined by RECIST criteria were used to compare lesion types. RESULTS: The 26 patients had a total of 83 lesions for comparison (38 receiving low-dose, 45 receiving no-dose). The average dose given to low-dose lesions was 7.3 Gy (1.1-19.4 Gy), and the average time to response was 56 days. Twenty-two out of 38 (58%) low-dose lesions met the PR/CR criteria for RECIST compared with 8 out of 45 (18%) no-dose lesions (P = 0.0001). The median change for longest diameter size for low-dose lesions was - 38.5% compared to 8% in no-dose lesions (P < 0.0001). Among the low-dose lesions that had at least one no-dose lesion within the same patient as a control (33 and 45 lesions respectively), 12 low-dose lesions (36%) responded without a corresponding response in their no-dose lesions; Conversely, two (4%) of the no-dose lesions responded without a corresponding response in their low-dose lesion (P = 0.0004). CONCLUSIONS: Low-dose radiation may increase systemic response rates of metastatic disease treated with high-dose radiation and immunotherapy.


Assuntos
Imunoterapia/mortalidade , Neoplasias/terapia , Radiocirurgia/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Terapia Combinada , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/imunologia , Neoplasias/patologia , Prognóstico , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Taxa de Sobrevida , Adulto Jovem
9.
Clin Cancer Res ; 24(22): 5735-5743, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-29784675

RESUMO

Purpose: Radiation is used extensively to treat localized cancer, but improved understanding of its effects on the immune system has increased interest in its potential systemic (abscopal) effects, particularly in combination with checkpoint inhibitors such as anti-PD1. The majority of patients either do not respond or develop resistance to monotherapy over time. Here, we investigated the efficacy of OX40 (CD134) stimulation as an alternative immunotherapeutic approach in combination with radiotherapy (XRT) in a murine model of anti-PD1-resistant lung tumors.Experimental Design: We established a bilateral tumor model in 129Sv/Ev mice using an anti-PD1-resistant lung tumor cell line. Primary tumors were treated with intratumoral injection of an OX40 agonist antibody, given as adjuvant therapy after XRT (36 Gy in three 12-Gy fractions), whereas secondary tumors were left untreated to investigate abscopal outcomes.Results: The combination of XRT followed by OX40 stimulation effectively inhibited local and systemic antitumor growth, limited lung metastases, and improved survival rates. This treatment regimen augmented CD4+ and CD8+ T-cell expansion. XRT induced the expression of OX40 on T cells in tumors and spleens and increased the percentages of splenic CD103+ dendritic cells.Conclusions: Our data extend the benefits of radiation to systemic disease control, especially when combined with anti-OX40 agonist to promote immunologically mediated abscopal effects. Moreover, this study provides a rational treatment approach and sequence to overcome anti-PD1-resistant poorly immunogenic tumors. Clin Cancer Res; 24(22); 5735-43. ©2018 AACR.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Neoplasias Pulmonares/metabolismo , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptores OX40/metabolismo , Animais , Linhagem Celular Tumoral , Quimiorradioterapia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/efeitos da radiação , Camundongos , Receptores OX40/antagonistas & inibidores , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Int J Radiat Oncol Biol Phys ; 85(1): e39-46, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23102837

RESUMO

PURPOSE: The aim of the study was to evaluate the prognostic value of prostate-specific antigen (PSA) response to neoadjuvant androgen deprivation therapy (ADT) prior to dose-escalated radiation therapy (RT) and long-term ADT in high-risk prostate cancer. METHODS AND MATERIALS: We reviewed the charts of all patients diagnosed with high-risk prostate cancer and treated with a combination of long-term ADT (median, 24 months) and dose-escalated (median, 75.6 Gy) RT between 1990 and 2007. The associations among patient, tumor, and treatment characteristics with biochemical response to neoadjuvant ADT and their effects on failure-free survival (FFS), time to distant metastasis (TDM), prostate cancer-specific mortality (PCSM) and overall survival (OS) were examined. RESULTS: A total of 196 patients met criteria for inclusion. Median follow-up time for patients alive at last contact was 7.0 years (range, 0.5-18.1 years). Multivariate analysis identified the pre-RT PSA concentration (<0.5 vs ≥0.5 ng/mL) as a significant independent predictor of FFS (P=.021), TDM (P=.009), PCSM (P=.039), and OS (P=.037). On multivariate analysis, pretreatment PSA (iPSA) and African-American race were significantly associated with failure to achieve a pre-RT PSA of <0.5 ng/mL. CONCLUSIONS: For high-risk prostate cancer patients treated with long-term ADT and dose-escalated RT, a pre-RT PSA level≥0.5 ng/mL after neoadjuvant ADT predicts for worse survival measures. Both elevated iPSA and African-American race are associated with increased risk of having a pre-RT PSA level≥0.5 ng/mL. These patients should be considered for clinical trials that test newer, more potent androgen-depleting therapies such as abiraterone and MDV3100 in combination with radiation.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/terapia , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Intervalo Livre de Doença , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Gradação de Tumores , Estadiamento de Neoplasias , Neoplasias da Próstata/etnologia , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Análise de Sobrevida , Fatores de Tempo
11.
Int J Radiat Oncol Biol Phys ; 85(3): 693-9, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22836052

RESUMO

PURPOSE: The benefit of adding androgen deprivation therapy (ADT) to dose-escalated radiation therapy (RT) for men with intermediate-risk prostate cancer is unclear; therefore, we assessed the impact of adding ADT to dose-escalated RT on freedom from failure (FFF). METHODS: Three groups of men treated with intensity modulated RT or 3-dimensional conformal RT (75.6-78 Gy) from 1993-2008 for prostate cancer were categorized as (1) 326 intermediate-risk patients treated with RT alone, (2) 218 intermediate-risk patients treated with RT and ≤6 months of ADT, and (3) 274 low-risk patients treated with definitive RT. Median follow-up was 58 months. Recursive partitioning analysis based on FFF using Gleason score (GS), T stage, and pretreatment PSA concentration was applied to the intermediate-risk patients treated with RT alone. The Kaplan-Meier method was used to estimate 5-year FFF. RESULTS: Based on recursive partitioning analysis, intermediate-risk patients treated with RT alone were divided into 3 prognostic groups: (1) 188 favorable patients: GS 6, ≤T2b or GS 3+4, ≤T1c; (2) 71 marginal patients: GS 3+4, T2a-b; and (3) 68 unfavorable patients: GS 4+3 or T2c disease. Hazard ratios (HR) for recurrence in each group were 1.0, 2.1, and 4.6, respectively. When intermediate-risk patients treated with RT alone were compared to intermediate-risk patients treated with RT and ADT, the greatest benefit from ADT was seen for the unfavorable intermediate-risk patients (FFF, 74% vs 94%, respectively; P=.005). Favorable intermediate-risk patients had no significant benefit from the addition of ADT to RT (FFF, 94% vs 95%, respectively; P=.85), and FFF for favorable intermediate-risk patients treated with RT alone approached that of low-risk patients treated with RT alone (98%). CONCLUSIONS: Patients with favorable intermediate-risk prostate cancer did not benefit from the addition of ADT to dose-escalated RT, and their FFF was nearly as good as patients with low-risk disease. In patients with GS 4+3 or T2c disease, the addition of ADT to dose-escalated RT did improve FFF.


Assuntos
Antagonistas de Androgênios/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Recidiva Local de Neoplasia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Idoso , Terapia Combinada/métodos , Intervalo Livre de Doença , Seguimentos , Humanos , Masculino , Análise Multivariada , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Radioterapia Conformacional , Radioterapia de Intensidade Modulada
12.
Cancer J ; 18(1): 1-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22290249

RESUMO

PURPOSE: This study aimed to evaluate the changes in outcome for men with localized prostate cancer treated with definitive external beam radiation therapy during a 20-year period at a comprehensive cancer center. METHODS: We categorized 2675 men with prostate cancer treated at MD Anderson Cancer Center with definitive external beam radiation therapy with or without androgen deprivation therapy into 3 treatment eras: 1987 to 1993 (n = 722), 1994 to 1999 (n = 828), and 2000 to 2007 (n = 1125). To help adjust for stage migration, patients were stratified according to risk group as defined by the National Comprehensive Cancer Network. Biochemical (Phoenix definition), local, distant, and any clinical failure, prostate-cancer specific survival, and overall survival were analyzed according to the Kaplan-Meier method. RESULTS: Median age was 68.5 years and median follow-up was 6.4 years. Fewer men in the most recent era had high-risk disease, and a higher proportion received 72 Gy or higher (99% vs 4%) and androgen deprivation therapy (60% vs 6%) than the earliest era. All risk groups treated in the modern era experienced improved rates of biochemical, local, and distant failure. In high-risk patients, decreased rates of distant failure and clinical failure led to improved prostate cancer-specific survival and overall survival. Local control was improved for intermediate- and high-risk patients, with a trend toward improvement in low-risk patients. On multivariate analysis, recent treatment era was closely correlated with a dose of 72 Gy or higher and treatment with androgen deprivation therapy and predicted for lower rates of biochemical, local, and distant failure. Androgen deprivation therapy, higher dose, and more recent treatment era predicted for improved prostate cancer-specific survival. DISCUSSION: During the last 20 years of prostate cancer irradiation, disease control outcomes have improved in all patients, leading to improved prostate cancer-specific survival and overall survival for men with high-risk disease. This may reflect advances in workup, staging accuracy, and prostate cancer treatment in the modern era.


Assuntos
Adenocarcinoma/mortalidade , Adenocarcinoma/radioterapia , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/radioterapia , Adenocarcinoma/tratamento farmacológico , Idoso , Antagonistas de Androgênios/uso terapêutico , Estudos de Coortes , Terapia Combinada , Humanos , Masculino , Estadiamento de Neoplasias , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Dosagem Radioterapêutica , Fatores de Risco , Taxa de Sobrevida , Texas/epidemiologia , Resultado do Tratamento
13.
Eur J Cancer ; 48(11): 1664-71, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22336663

RESUMO

BACKGROUND: A competing risks analysis was undertaken to identify subgroups at greatest risk of dying from prostate cancer (PC) after definitive external beam radiation therapy (RT)±androgen deprivation therapy (ADT) in the prostate specific antigen (PSA) era. METHODS: Outcomes of 2675 men with localised PC treated with RT±ADT from 1987-2007 were analysed. Prostate cancer-specific mortality (PCSM) and non-PCSM rates were calculated after stratifying patients according to National Comprehensive Cancer Network (NCCN) risk-group, RT dose, use of ADT and age at treatment. RESULTS: Only 0.2% of low-risk men died of PC 10 years after treatment. All of these deaths occurred in patients treated with < 72 Gy, and only one patient ≥ 70 years old who received ≥ 72 Gy died of PC at last follow-up. Likewise, none of the patients with intermediate-risk disease treated with ≥ 72 Gy and ADT died of PC at 10 years, and the highest 10-year rate of PCSM was seen in men ≥ 70 years old treated with < 72 Gy without ADT (5.1%). Among high-risk men < 70 years old, treatment with RT dose < 72 Gy without ADT yielded similar 10-year rates of PCSM (15.2%) and non-PCSM (18.5%), whereas men treated with ≥ 72 Gy and ADT were twice as likely to die from other causes (16.2%) than PC (9.4%). In high-risk men ≥ 70 years old, dose-escalation with ADT reduced 10-year PCSM from 14% to 4%, and most deaths were due to other causes. CONCLUSION: Low- and intermediate-risk patients treated with definitive RT are unlikely to die of PC. PCSM is higher in men with high-risk disease but may be reduced with dose-escalation and ADT, although patients are still twice as likely to die of other causes.


Assuntos
Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/radioterapia , Fatores Etários , Idoso , Antagonistas de Androgênios/uso terapêutico , Causas de Morte , Humanos , Masculino , Neoplasias da Próstata/tratamento farmacológico , Dosagem Radioterapêutica , Medição de Risco , Taxa de Sobrevida , Estados Unidos
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