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1.
Conserv Biol ; : e14247, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488677

RESUMO

Climate change is one of the most important drivers of ecosystem change, the global-scale impacts of which will intensify over the next 2 decades. Estimating the timing of unprecedented changes is not only challenging but is of great importance for the development of ecosystem conservation guidelines. Time of emergence (ToE) (point at which climate change can be differentiated from a previous climate), a widely applied concept in climatology studies, provides a robust but unexplored approach for assessing the risk of ecosystem collapse, as described by the C criterion of the International Union for Conservation of Nature's Red List of Ecosystems (RLE). We identified 3 main theoretical considerations of ToE for RLE assessment (degree of stability, multifactorial instead of one-dimensional analyses, and hallmarks of ecosystem collapse) and 4 sources of uncertainty when applying ToE methodology (intermodel spread, historical reference period, consensus among variables, and consideration of different scenarios), which aims to avoid misuse and errors while promoting a proper application of the framework by scientists and practitioners. The incorporation of ToE for the RLE assessments adds important information for conservation priority setting that allows prediction of changes within and beyond the time frames proposed by the RLE.


Perspectivas sobre el momento del colapso ecosistémico en un clima cambiante Resumen El cambio climático es uno de los principales causantes del cambio ecosistémico, cuyo impacto a escala global se intensificará en las próximas dos décadas. No sólo es un reto estimar el momento de los cambios sin precedentes, sino también es de gran importancia para el desarrollo de las directrices de conservación de los ecosistemas. El momento de aparición (MdA), el punto en el que el cambio climático puede diferenciarse de un clima previo; es un concepto de aplicación extensa en los estudios de climatología y proporciona una estrategia sólida pero poco explorada para evaluar el riesgo del colapso ecosistémico, como está descrito por el criterio C de la Lista Roja de Ecosistemas (LRE) de la Unión Internacional para la Conservación de la Naturaleza. Identificamos las tres consideraciones teóricas del MdA para la evaluación de la LRE (grado de estabilidad, análisis multifactoriales en vez de unidimensionales y distintivos del colapso ecosistémico) y cuatro fuentes de incertidumbre cuando se aplica la metodología MdA (difusión intermodelo, periodo de referencia histórica, consenso entre las variables y consideración de escenarios distintos), la cual busca evitar el mal uso y los errores mientras se promueve una aplicación adecuada del marco de los científicos y lo practicantes. La incorporación del MdA a las evaluaciones de la LRE añade información importante para el establecimiento de prioridades de conservación que permiten la predicción de cambios dentro y más allá del marco temporal propuesto por la LRE.

2.
Lancet Oncol ; 24(5): 509-522, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37142373

RESUMO

BACKGROUND: Low-intensity pulsed ultrasound with concomitant administration of intravenous microbubbles (LIPU-MB) can be used to open the blood-brain barrier. We aimed to assess the safety and pharmacokinetics of LIPU-MB to enhance the delivery of albumin-bound paclitaxel to the peritumoural brain of patients with recurrent glioblastoma. METHODS: We conducted a dose-escalation phase 1 clinical trial in adults (aged ≥18 years) with recurrent glioblastoma, a tumour diameter of 70 mm or smaller, and a Karnofsky performance status of at least 70. A nine-emitter ultrasound device was implanted into a skull window after tumour resection. LIPU-MB with intravenous albumin-bound paclitaxel infusion was done every 3 weeks for up to six cycles. Six dose levels of albumin-bound paclitaxel (40 mg/m2, 80 mg/m2, 135 mg/m2, 175 mg/m2, 215 mg/m2, and 260 mg/m2) were evaluated. The primary endpoint was dose-limiting toxicity occurring during the first cycle of sonication and albumin-bound paclitaxel chemotherapy. Safety was assessed in all treated patients. Analyses were done in the per-protocol population. Blood-brain barrier opening was investigated by MRI before and after sonication. We also did pharmacokinetic analyses of LIPU-MB in a subgroup of patients from the current study and a subgroup of patients who received carboplatin as part of a similar trial (NCT03744026). This study is registered with ClinicalTrials.gov, NCT04528680, and a phase 2 trial is currently open for accrual. FINDINGS: 17 patients (nine men and eight women) were enrolled between Oct 29, 2020, and Feb 21, 2022. As of data cutoff on Sept 6, 2022, median follow-up was 11·89 months (IQR 11·12-12·78). One patient was treated per dose level of albumin-bound paclitaxel for levels 1 to 5 (40-215 mg/m2), and 12 patients were treated at dose level 6 (260 mg/m2). A total of 68 cycles of LIPU-MB-based blood-brain barrier opening were done (median 3 cycles per patient [range 2-6]). At a dose of 260 mg/m2, encephalopathy (grade 3) occurred in one (8%) of 12 patients during the first cycle (considered a dose-limiting toxicity), and in one other patient during the second cycle (grade 2). In both cases, the toxicity resolved and treatment continued at a lower dose of albumin-bound paclitaxel, with a dose of 175 mg/m2 in the case of the grade 3 encephalopathy, and to 215 mg/m2 in the case of the grade 2 encephalopathy. Grade 2 peripheral neuropathy was observed in one patient during the third cycle of 260 mg/m2 albumin-bound paclitaxel. No progressive neurological deficits attributed to LIPU-MB were observed. LIPU-MB-based blood-brain barrier opening was most commonly associated with immediate yet transient grade 1-2 headache (12 [71%] of 17 patients). The most common grade 3-4 treatment-emergent adverse events were neutropenia (eight [47%]), leukopenia (five [29%]), and hypertension (five [29%]). No treatment-related deaths occurred during the study. Imaging analysis showed blood-brain barrier opening in the brain regions targeted by LIPU-MB, which diminished over the first 1 h after sonication. Pharmacokinetic analyses showed that LIPU-MB led to increases in the mean brain parenchymal concentrations of albumin-bound paclitaxel (from 0·037 µM [95% CI 0·022-0·063] in non-sonicated brain to 0·139 µM [0·083-0·232] in sonicated brain [3·7-times increase], p<0·0001) and carboplatin (from 0·991 µM [0·562-1·747] in non-sonicated brain to 5·878 µM [3·462-9·980] µM in sonicated brain [5·9-times increase], p=0·0001). INTERPRETATION: LIPU-MB using a skull-implantable ultrasound device transiently opens the blood-brain barrier allowing for safe, repeated penetration of cytotoxic drugs into the brain. This study has prompted a subsequent phase 2 study combining LIPU-MB with albumin-bound paclitaxel plus carboplatin (NCT04528680), which is ongoing. FUNDING: National Institutes of Health and National Cancer Institute, Moceri Family Foundation, and the Panattoni family.


Assuntos
Encefalopatias , Glioblastoma , Adulto , Masculino , Humanos , Feminino , Adolescente , Paclitaxel Ligado a Albumina/efeitos adversos , Carboplatina , Glioblastoma/diagnóstico por imagem , Glioblastoma/tratamento farmacológico , Barreira Hematoencefálica , Paclitaxel , Encefalopatias/induzido quimicamente , Encefalopatias/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
3.
Biomarkers ; 22(7): 689-697, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28276926

RESUMO

CONTEXT: Clinical study of breast cancer patients in Chicago, IL, USA. OBJECTIVE: Ascertain the utility of measurements of single-strand breaks (SSB) in DNA for assessment of breast cancer risk. METHODS: Fine-needle aspirates of the breast, SSB by nick translation, percent breast density (PBD), Gail model risk, cumulative methylation index (CMI), enzymes of DNA repair and tissue antioxidants. RESULTS: DNA repair enzymes and 4-hydroxyestradiol were negatively associated with SSB; CMI and PBD were positively associated. CONCLUSIONS: Quantitative measurement of SSBs by this procedure indicates the relative number of SSBs and is related to promoter methylation, antioxidant availability and percent breast density.


Assuntos
Neoplasias da Mama/genética , Quebras de DNA de Cadeia Simples , Estrogênios/análise , Adulto , Densidade da Mama , Neoplasias da Mama/diagnóstico , Dano ao DNA , Enzimas Reparadoras do DNA/análise , Estrogênios de Catecol/análise , Feminino , Humanos , Pessoa de Meia-Idade , Risco
4.
Nat Commun ; 15(1): 4698, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844770

RESUMO

Given the marginal penetration of most drugs across the blood-brain barrier, the efficacy of various agents remains limited for glioblastoma (GBM). Here we employ low-intensity pulsed ultrasound (LIPU) and intravenously administered microbubbles (MB) to open the blood-brain barrier and increase the concentration of liposomal doxorubicin and PD-1 blocking antibodies (aPD-1). We report results on a cohort of 4 GBM patients and preclinical models treated with this approach. LIPU/MB increases the concentration of doxorubicin by 2-fold and 3.9-fold in the human and murine brains two days after sonication, respectively. Similarly, LIPU/MB-mediated blood-brain barrier disruption leads to a 6-fold and a 2-fold increase in aPD-1 concentrations in murine brains and peritumoral brain regions from GBM patients treated with pembrolizumab, respectively. Doxorubicin and aPD-1 delivered with LIPU/MB upregulate major histocompatibility complex (MHC) class I and II in tumor cells. Increased brain concentrations of doxorubicin achieved by LIPU/MB elicit IFN-γ and MHC class I expression in microglia and macrophages. Doxorubicin and aPD-1 delivered with LIPU/MB results in the long-term survival of most glioma-bearing mice, which rely on myeloid cells and lymphocytes for their efficacy. Overall, this translational study supports the utility of LIPU/MB to potentiate the antitumoral activities of doxorubicin and aPD-1 for GBM.


Assuntos
Barreira Hematoencefálica , Neoplasias Encefálicas , Doxorrubicina , Microbolhas , Receptor de Morte Celular Programada 1 , Doxorrubicina/farmacologia , Doxorrubicina/administração & dosagem , Doxorrubicina/uso terapêutico , Doxorrubicina/análogos & derivados , Animais , Humanos , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Camundongos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/imunologia , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Glioma/tratamento farmacológico , Glioma/imunologia , Glioma/patologia , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Feminino , Sistemas de Liberação de Medicamentos , Ondas Ultrassônicas , Glioblastoma/tratamento farmacológico , Glioblastoma/imunologia , Glioblastoma/patologia , Masculino , Microglia/efeitos dos fármacos , Microglia/metabolismo , Camundongos Endogâmicos C57BL , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacologia , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/administração & dosagem , Polietilenoglicóis
5.
Biomed Pharmacother ; 162: 114607, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37001185

RESUMO

Aggressive estrogen receptor (ER) positive breast cancer is frequently tamoxifen-resistant; alternative endocrine approaches exist for therapy, but not for prevention, particularly in premenopausal women. We examined the efficacy of the selective ER modulator (Z-endoxifen) as monotherapy and in combination with the selective progesterone receptor modulators (onapristone and ulipristal acetate) in the tamoxifen-insensitive C3(1)/SV40TAg mouse mammary tumorigenesis model. Unlike tamoxifen at human equivalent dose (HED) 101 mg/day, endoxifen at HED 24 mg/day significantly increased latency and reduced tumor growth relative to untreated controls. Ulipristal acetate (UPA) at HED 81 mg/day also significantly increased latency however failed to inhibit tumor growth, while onapristone (HED 98 mg/day) had no tumor prevention efficacy in this model. Addition of UPA to endoxifen did not enhance preventive efficacy over endoxifen alone. The expression of genes associated with cell cycle, cell proliferation and extracellular matrix remodeling was similarly repressed by endoxifen and UPA however only endoxifen significantly downregulated prominent genes associated with poor prognosis (Col11a1, Il17b, Pdgfa, Tnfrsf11a). Our results indicate that endoxifen can prevent breast cancers, even when tamoxifen-resistant, through its role in favorable tissue remodeling and immunomodulation.


Assuntos
Neoplasias da Mama , Tamoxifeno , Feminino , Camundongos , Humanos , Animais , Linhagem Celular Tumoral , Tamoxifeno/farmacologia , Neoplasias da Mama/tratamento farmacológico , Proliferação de Células , Microambiente Tumoral
6.
Cancer Prev Res (Phila) ; 16(1): 47-55, 2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36228112

RESUMO

PREVENTION RELEVANCE: Bexarotene is a rexinoid that has been shown to prevent mammary tumors in mouse models but oral dosing has toxicities. This phase I study evaluates topical bexarotene, as a potential chemoprevention agent, for safety and toxicity in high-risk women for breast cancer.


Assuntos
Bexaroteno , Neoplasias , Feminino , Bexaroteno/administração & dosagem , Bexaroteno/efeitos adversos , Neoplasias/tratamento farmacológico , Humanos , Administração Tópica , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos
7.
Inhal Toxicol ; 24(14): 985-94, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23216159

RESUMO

The toxicity and toxicokinetics of tungsten blue oxide (TBO) were examined. TBO is an intermediate in the production of tungsten powder, and has shown the potential to cause cellular damage in in vitro studies. However, in vivo evidence seems to indicate a lack of adverse effects. The present study was undertaken to address the dearth of longer-term inhalation toxicity studies of tungsten oxides by investigating the biological responses induced by TBO when administered via nose-only inhalation to rats at levels of 0.08, 0.325, and 0.65 mg TBO/L of air for 6 h/day for 28 consecutive days, followed by a 14-day recovery period. Inhaled TBO was absorbed systemically and blood levels of tungsten increased as inhaled concentration increased. Among the tissues analyzed for tungsten levels, lung, femur and kidney showed increased levels, with lung at least an order of magnitude greater than kidney or femur. By exposure day 14, tungsten concentration in tissues had reached steady-state. Increased lung weight was noted for both terminal and recovery animals and was attributed to deposition of TBO in the lungs, inducing a macrophage influx. Microscopic evaluation of tissues revealed a dose-related increase in alveolar pigmented macrophages, alveolar foreign material and individual alveolar foamy macrophages in lung. After a recovery period there was a slight reduction in the incidence and severity of histopathological findings. Based on the absence of other adverse effects, the increased lung weights and the microscopic findings were interpreted as nonadverse response to exposure and were not considered a specific reaction to TBO.


Assuntos
Exposição por Inalação , Pulmão/efeitos dos fármacos , Óxidos/toxicidade , Material Particulado/toxicidade , Tungstênio/toxicidade , Aerossóis , Animais , Área Sob a Curva , Biomarcadores/sangue , Biomarcadores/urina , Feminino , Fêmur/metabolismo , Células Espumosas/efeitos dos fármacos , Células Espumosas/imunologia , Células Espumosas/metabolismo , Meia-Vida , Rim/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Macrófagos Alveolares/efeitos dos fármacos , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Masculino , Taxa de Depuração Metabólica , Óxidos/sangue , Óxidos/farmacocinética , Tamanho da Partícula , Material Particulado/sangue , Material Particulado/farmacocinética , Ratos , Ratos Sprague-Dawley , Medição de Risco , Distribuição Tecidual , Tungstênio/sangue , Tungstênio/farmacocinética
8.
Biomedicines ; 9(9)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34572438

RESUMO

Pandemic SARS-CoV-2 causes a mild to severe respiratory disease called coronavirus disease 2019 (COVID-19). While control of the SARS-CoV-2 spread partly depends on vaccine-induced or naturally acquired protective herd immunity, antiviral strategies are still needed to manage COVID-19. Enisamium is an inhibitor of influenza A and B viruses in cell culture and clinically approved in countries of the Commonwealth of Independent States. In vitro, enisamium acts through metabolite VR17-04 and inhibits the activity of the influenza A virus RNA polymerase. Here we show that enisamium can inhibit coronavirus infections in NHBE and Caco-2 cells, and the activity of the SARS-CoV-2 RNA polymerase in vitro. Docking and molecular dynamics simulations provide insight into the mechanism of action and indicate that enisamium metabolite VR17-04 prevents GTP and UTP incorporation. Overall, these results suggest that enisamium is an inhibitor of SARS-CoV-2 RNA synthesis in vitro.

9.
medRxiv ; 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33469600

RESUMO

Pandemic SARS-CoV-2 causes a mild to severe respiratory disease called Coronavirus Disease 2019 (COVID-19). Control of SARS-CoV-2 spread will depend on vaccine-induced or naturally acquired protective herd immunity. Until then, antiviral strategies are needed to manage COVID-19, but approved antiviral treatments, such as remdesivir, can only be delivered intravenously. Enisamium (laboratory code FAV00A, trade name Amizon®) is an orally active inhibitor of influenza A and B viruses in cell culture and clinically approved in countries of the Commonwealth of Independent States. Here we show that enisamium can inhibit SARS-CoV-2 infections in NHBE and Caco-2 cells. In vitro, the previously identified enisamium metabolite VR17-04 directly inhibits the activity of the SARS-CoV-2 RNA polymerase. Docking and molecular dynamics simulations suggest that VR17-04 prevents GTP and UTP incorporation. To confirm enisamium's antiviral properties, we conducted a double-blind, randomized, placebo-controlled trial in adult, hospitalized COVID-19 patients, which needed medical care either with or without supplementary oxygen. Patients received either enisamium (500 mg per dose) or placebo for 7 days. A pre-planned interim analysis showed in the subgroup of patients needing supplementary oxygen (n = 77) in the enisamium group a mean recovery time of 11.1 days, compared to 13.9 days for the placebo group (log-rank test; p=0.0259). No significant difference was found for all patients (n = 373) or those only needing medical care (n = 296). These results thus suggest that enisamium is an inhibitor of SARS-CoV-2 RNA synthesis and that enisamium treatment shortens the time to recovery for COVID-19 patients needing oxygen.

10.
Clin Pharmacol Ther ; 109(3): 728-738, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32996592

RESUMO

Oral breast cancer prevention medications entail systemic exposure, limiting acceptance by high-risk women. Delivery through the breast skin, although an attractive alternative, requires demonstration of drug distribution throughout the breast. We conducted a randomized double-blind, placebo-controlled phase II clinical trial comparing telapristone acetate, a progesterone receptor antagonist, administered orally (12 mg/day) or transdermally (12 mg/breast) for 4 ± 1 weeks to women planning mastectomy. Plasma and tissue concentrations, measured at five locations in the mastectomy specimen using liquid chromatography tandem mass spectrometry were compared. In 60 evaluable subjects, median drug concentration (ng/g tissue) was 103 (interquartile range (IQR): 46.3-336) in the oral vs. 2.82 (IQR: 1.4-5.5) in the transdermal group. Despite poor dermal permeation, within-breast drug distribution pattern was identical in both groups (R2  = 0.88, P = 0.006), demonstrating that transdermally and orally delivered drug is distributed similarly through the breast, and is strongly influenced by tissue adiposity (P < 0.0001). Other skin-penetrant drugs should be tested for breast cancer prevention.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Terapia Neoadjuvante , Norpregnadienos/administração & dosagem , Absorção Cutânea , Adiposidade , Administração Cutânea , Administração Oral , Adulto , Antineoplásicos/efeitos adversos , Antineoplásicos/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/cirurgia , Quimioterapia Adjuvante , Cromatografia Líquida , Método Duplo-Cego , Monitoramento de Medicamentos , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Norpregnadienos/efeitos adversos , Norpregnadienos/sangue , Espectrometria de Massas em Tandem , Fatores de Tempo , Distribuição Tecidual , Resultado do Tratamento , Estados Unidos
11.
Sci Transl Med ; 13(584)2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33692132

RESUMO

Glioblastoma (GBM) is one of the most difficult cancers to effectively treat, in part because of the lack of precision therapies and limited therapeutic access to intracranial tumor sites due to the presence of the blood-brain and blood-tumor barriers. We have developed a precision medicine approach for GBM treatment that involves the use of brain-penetrant RNA interference-based spherical nucleic acids (SNAs), which consist of gold nanoparticle cores covalently conjugated with radially oriented and densely packed small interfering RNA (siRNA) oligonucleotides. On the basis of previous preclinical evaluation, we conducted toxicology and toxicokinetic studies in nonhuman primates and a single-arm, open-label phase 0 first-in-human trial (NCT03020017) to determine safety, pharmacokinetics, intratumoral accumulation and gene-suppressive activity of systemically administered SNAs carrying siRNA specific for the GBM oncogene Bcl2Like12 (Bcl2L12). Patients with recurrent GBM were treated with intravenous administration of siBcl2L12-SNAs (drug moniker: NU-0129), at a dose corresponding to 1/50th of the no-observed-adverse-event level, followed by tumor resection. Safety assessment revealed no grade 4 or 5 treatment-related toxicities. Inductively coupled plasma mass spectrometry, x-ray fluorescence microscopy, and silver staining of resected GBM tissue demonstrated that intravenously administered SNAs reached patient tumors, with gold enrichment observed in the tumor-associated endothelium, macrophages, and tumor cells. NU-0129 uptake into glioma cells correlated with a reduction in tumor-associated Bcl2L12 protein expression, as indicated by comparison of matched primary tumor and NU-0129-treated recurrent tumor. Our results establish SNA nanoconjugates as a potential brain-penetrant precision medicine approach for the systemic treatment of GBM.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Nanopartículas Metálicas , Ácidos Nucleicos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Glioblastoma/genética , Glioblastoma/terapia , Ouro , Humanos , Proteínas Musculares/metabolismo , Recidiva Local de Neoplasia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Interferência de RNA
12.
Clin Cancer Res ; 26(2): 477-486, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31831565

RESUMO

PURPOSE: Paclitaxel shows little benefit in the treatment of glioma due to poor penetration across the blood-brain barrier (BBB). Low-intensity pulsed ultrasound (LIPU) with microbubble injection transiently disrupts the BBB allowing for improved drug delivery to the brain. We investigated the distribution, toxicity, and efficacy of LIPU delivery of two different formulations of paclitaxel, albumin-bound paclitaxel (ABX) and paclitaxel dissolved in cremophor (CrEL-PTX), in preclinical glioma models. EXPERIMENTAL DESIGN: The efficacy and biodistribution of ABX and CrEL-PTX were compared with and without LIPU delivery. Antiglioma activity was evaluated in nude mice bearing intracranial patient-derived glioma xenografts (PDX). Paclitaxel biodistribution was determined in sonicated and nonsonicated nude mice. Sonications were performed using a 1 MHz LIPU device (SonoCloud), and fluorescein was used to confirm and map BBB disruption. Toxicity of LIPU-delivered paclitaxel was assessed through clinical and histologic examination of treated mice. RESULTS: Despite similar antiglioma activity in vitro, ABX extended survival over CrEL-PTX and untreated control mice with orthotropic PDX. Ultrasound-mediated BBB disruption enhanced paclitaxel brain concentration by 3- to 5-fold for both formulations and further augmented the therapeutic benefit of ABX. Repeated courses of LIPU-delivered CrEL-PTX and CrEL alone were lethal in 42% and 37.5% of mice, respectively, whereas similar delivery of ABX at an equivalent dose was well tolerated. CONCLUSIONS: Ultrasound delivery of paclitaxel across the BBB is a feasible and effective treatment for glioma. ABX is the preferred formulation for further investigation in the clinical setting due to its superior brain penetration and tolerability compared with CrEL-PTX.


Assuntos
Albuminas/farmacologia , Albuminas/farmacocinética , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos/métodos , Glioma/tratamento farmacológico , Paclitaxel/farmacologia , Paclitaxel/farmacocinética , Polietilenoglicóis/química , Ultrassonografia/métodos , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Feminino , Glioma/patologia , Masculino , Camundongos , Camundongos Nus , Microbolhas/uso terapêutico , Nanopartículas/química , Taxa de Sobrevida , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Clin Cancer Res ; 26(1): 25-34, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31570566

RESUMO

PURPOSE: Selective progesterone receptor modulators (SPRMs) show preclinical activity against hormone-sensitive breast cancer, but have not been tested in patients with early, treatment-naïve tumors. PATIENTS AND METHODS: In a double-blind presurgical window trial of oral telapristone acetate (TPA) 12 mg daily versus placebo, 70 patients with early-stage breast cancer were randomized 1:1 (stratified by menopause) and treated for 2 to 10 weeks. The primary endpoint was change in Ki67 between diagnostic biopsy and surgical specimens. Gene expression pre- and posttherapy was assessed using RNA-sequencing and gene set enrichment analysis was performed to determine pathways enriched in response to TPA and placebo treatments. RESULTS: Among 61 evaluable women (29 placebo and 32 telapristone acetate), 91% of tumors were ER/PR positive. The mean Ki67 declined by 5.5% in all women treated with telapristone acetate (P = 0.003), and by 4.2% in all women treated with placebo (P = 0.04). After menopausal stratification, the Ki67 decline remained significant in 22 telapristone acetate-treated premenopausal women (P = 0.03). Differential gene expression analysis showed no significant modulation overall. However, in a subset of tumors that demonstrated ≥30% relative reduction in Ki67 in the telapristone acetate group, genes related to cell-cycle progression, and those in the HER2 amplicon were significantly downregulated. In contrast, no significantly enriched pathways were identified in the placebo group. CONCLUSIONS: Patients treated with telapristone acetate whose Ki67 decreased by ≥30% demonstrated a selective antiproliferative signal, with a potentially important effect on HER2 amplicon genes. Evaluation of SPRMs in a neoadjuvant trial is merited, with attention to predictors of response to SPRM therapy, and inclusion of pre- and postmenopausal women.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Antagonistas de Hormônios/uso terapêutico , Norpregnadienos/uso terapêutico , Receptores de Progesterona/antagonistas & inibidores , Antineoplásicos/uso terapêutico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Método Duplo-Cego , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Antígeno Ki-67/metabolismo , Menopausa , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Receptor ErbB-2/genética , Análise de Sequência de RNA/métodos , Resultado do Tratamento
15.
Inhal Toxicol ; 21(8): 688-704, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19555222

RESUMO

Activated charcoal (AC) filtration reportedly decreases the yields of smoke vapor phase constituents including some identified as human carcinogens and respiratory irritants. Non-clinical studies including chemical smoke analysis, in vitro cytotoxicity and mutagenicity (bacterial and mammalian cells), and in vivo subchronic rat inhalation studies were carried out using machine smoking at ISO conditions with lit-end research cigarettes containing AC filters. The objective was to assess whether AC filter technology would alter the established toxicity profile of mainstream smoke by increasing or decreasing any known toxicological properties, or elicit new ones. The reduced yield of vapor phase irritants from AC filter cigarettes correlated with markedly decreased in vitro cytotoxicity and in vivo morphology of the nose and lower respiratory tract. Increased yields of particulate phase constituents (e.g. polycyclic aromatic hydrocarbons) in AC filtered smoke were noted in comparison to controls in some studies. The in vitro bacterial mutagenicity of AC filtered smoke particulate preparations was occasionally increased over control levels. Laryngeal epithelial thickness was increased in some rats inhaling AC filtered smoke in comparison to controls, an effect perhaps related to higher inspiratory flow. When tested under more intense Massachusetts Department of Public Health smoking conditions, AC filter associated reductions in vapor phase constituent yields were smaller than those seen with ISO conditions, but the effect on in vitro cytotoxicity remained.


Assuntos
Carvão Vegetal/administração & dosagem , Mutagênicos/toxicidade , Nicotiana/toxicidade , Fumaça/efeitos adversos , Fumar/efeitos adversos , Animais , Sobrevivência Celular/efeitos dos fármacos , Carvão Vegetal/química , Feminino , Filtração , Humanos , Exposição por Inalação/efeitos adversos , Laringe/efeitos dos fármacos , Laringe/patologia , Linfoma/tratamento farmacológico , Linfoma/enzimologia , Linfoma/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Testes de Mutagenicidade , Mutação , Ratos , Ratos Sprague-Dawley , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/patologia , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Timidina Quinase/genética , Timidina Quinase/metabolismo , Nicotiana/química , Poluição por Fumaça de Tabaco
16.
Int J Toxicol ; 27(5): 387-95, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19037809

RESUMO

Spunbond, nonwoven fabrics consisting of polyethylene and polyethylene terephthalate, which meet food contact requirements, may be used as pouch materials for products containing food and/or flavor ingredients that are held in the mouth. In these situations ingestion may occur, resulting in exposure to the fabric and potentially antimony, a catalyst used in polyethylene terephthalate. To assess potential adverse effects when such a material is ingested, a 13 week dietary study in Sprague-Dawley CD rats and a Salmonella reverse mutation assay were conducted. Ground fabric was dosed at target concentrations of 0.5%, 2.5%, and 5% in the dietary study. Antimony trioxide in the polyethylene terephthalate was used to determine the test material concentration in the diet and was also assessed for bioavailability. Detectable levels of antimony were found in 2/20 blood samples of control rats, and in 20/20 high-dose group rats. No toxicologically relevant treatment related effects were observed in any of end points evaluated in the feeding study. In the mutagenicity assay, ground fabric was extracted in phosphate buffered saline or dimethysulfoxide and tested in Salmonella strains TA98, TA100, TA102, TA1535, and TA1537 with and without S9 activation. No mutagenic response was observed at any dose level tested. These results demonstrate that repeated daily ingestion of a spunbond, nonwoven polymer fabric consisting of polyethylene and polyethylene terephthalate for up to 13 weeks is well tolerated in rats, with no apparent target-organ toxicity at dietary levels up to 5%, and that fabric extracts are not mutagenic in a bacterial reverse mutation assay.


Assuntos
Polietilenotereftalatos/toxicidade , Polietileno/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Têxteis/toxicidade , Administração Oral , Animais , Relação Dose-Resposta a Droga , Feminino , Masculino , Testes de Mutagenicidade , Mutação , Ratos , Ratos Sprague-Dawley , Salmonella typhimurium/genética , Testes de Toxicidade Crônica
17.
Antivir Chem Chemother ; 26: 2040206618811416, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30466301

RESUMO

AIMS: New therapeutics for the control of influenza virus infections are needed to alleviate the burden caused by seasonal epidemics and occasional pandemics, and to overcome the potential risk of drug-resistance emergence. Enisamium iodide (Amizon®, Farmak) is currently approved for clinical use for the treatment of influenza in 11 countries which includes Ukraine, Russia, Belarus, Kazakhstan, and Uzbekistan. However, experimental evidence of the antiviral activity of enisamium has not been reported. METHODS: Antiviral activity of enisamium was assessed by virus yield reduction assays using differentiated normal human bronchial epithelial cells. Permeability of enisamium into differentiated normal human bronchial epithelial cells and its cytotoxicity were also assessed, and comparisons with other cell lines were made. RESULTS: Enisamium inhibited replication of multiple subtypes of influenza A viruses, including seasonal H1N1, 2009 pandemic H1N1, seasonal H3N2, the zoonotic H5N1 and H7N9, neuraminidase inhibitor-resistant variant carrying the H275Y NA substitution (N1 numbering), and influenza B virus at doses 23- to 64-fold lower than cytotoxic concentrations. The permeability of enisamium in Madin-Darby canine kidney cells (where no antiviral activity was found) was less than 0.08%, while higher permeability was observed in differentiated normal human bronchial epithelial cells (1.9%). The kinetics of enisamium intracellular uptake in differentiated normal human bronchial epithelial cells was concentration dependent. In time-of-addition experiments in differentiated normal human bronchial epithelial cells, enisamium treatment within 4 h after A(H1N1) virus inoculation resulted in 100-fold or greater reductions in virus titers, suggesting that it affects an early stage of the virus life cycle. CONCLUSIONS: Enisamium exhibits antiviral activity against influenza viruses in vitro, supporting the reported clinical efficacy against influenza virus infections.


Assuntos
Antivirais/farmacologia , Brônquios/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/microbiologia , Vírus da Influenza A/efeitos dos fármacos , Piridinas/farmacologia , Animais , Antivirais/síntese química , Antivirais/química , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Humanos , Células Madin Darby de Rim Canino , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piridinas/síntese química , Piridinas/química , Compostos de Piridínio , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
18.
Cancer Prev Res (Phila) ; 11(9): 557-568, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29954758

RESUMO

Sex steroid hormones contribute to breast cancer development, but data on concentrations of these within breast tissue are limited. We performed simultaneous multiparameter measurement of breast sex steroids, breast epithelial cytology, and DNA methylation in 119 healthy women (54 pre- and 65 postmenopausal) without a history of breast cancer. Random fine-needle aspiration (rFNA) of the breast was performed simultaneously with blood collection. Breast samples were analyzed by LC/MS-MS for estrone, estradiol, progesterone, androstenedione, and testosterone. Blood samples were assayed for estradiol and progesterone by immunoassay. Cytomorphology was classified using the Masood Score, and DNA methylation of eight genes was analyzed using quantitative multiplexed methylation-specific PCR, and expressed as the cumulative methylation index (CMI). Serum and breast concentrations of estradiol and progesterone showed significant correlation (Spearman r = 0.34, Padj = 0.001 and r = 0.69, Padj < 0.0006, respectively). Progesterone concentration was significantly higher in the premenopausal breast (Padj < 0.0008), and showed a luteal surge. Breast estrone and estradiol concentrations did not differ significantly by menopause, but androstenedione concentration was higher in the breasts of postmenopausal women (P = 0.026 and Padj = 0.208). Breast androgens were significantly correlated with breast density (Spearman r = 0.27, Padj = 0.02 for testosterone) and CMI (Spearman r = 0.3, Padj = 0.038 for androstenedione). Our data indicate that future larger studies of breast steroid hormones along with other parameters are feasible. Significant associations of breast androgen concentrations with breast density and gene methylation warrant future study. Cancer Prev Res; 11(9); 557-68. ©2018 AACR.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Mama/patologia , Metilação de DNA , Hormônios Esteroides Gonadais/análise , Biomarcadores Tumorais/metabolismo , Biópsia por Agulha Fina , Mama/metabolismo , Densidade da Mama/fisiologia , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Estudos de Viabilidade , Feminino , Hormônios Esteroides Gonadais/metabolismo , Humanos , Pessoa de Meia-Idade , Pós-Menopausa/metabolismo , Pré-Menopausa/metabolismo , Estudos Prospectivos , Fatores de Risco
19.
Clin Cancer Res ; 24(23): 5830-5840, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30061364

RESUMO

PURPOSE: Only one chemical class of topoisomerase I (TOP1) inhibitors is FDA approved, the camptothecins with irinotecan and topotecan widely used. Because of their limitations (chemical instability, drug efflux-mediated resistance, and diarrhea), novel TOP1 inhibitors are warranted. Indenoisoquinoline non-camptothecin topoisomerase I (TOP1) inhibitors overcome chemical instability and drug resistance that limit camptothecin use. Three indenoisoquinolines, LMP400 (indotecan), LMP776 (indimitecan), and LMP744, were examined in a phase I study for lymphoma-bearing dogs to evaluate differential efficacy, pharmacodynamics, toxicology, and pharmacokinetics. EXPERIMENTAL DESIGN: Eighty-four client-owned dogs with lymphomas were enrolled in dose-escalation cohorts for each indenoisoquinoline, with an expansion phase for LMP744. Efficacy, tolerability, pharmacokinetics, and target engagement were determined. RESULTS: The MTDs were 17.5 mg/m2 for LMP 776 and 100 mg/m2 for LMP744; bone marrow toxicity was dose-limiting; up to 65 mg/m2 LMP400 was well-tolerated and MTD was not reached. None of the drugs induced notable diarrhea. Sustained tumor accumulation was observed for LMP744; γH2AX induction was demonstrated in tumors 2 and 6 hours after treatment; a decrease in TOP1 protein was observed in most lymphoma samples across all compounds and dose levels, which is consistent with the fact that tumor response was also observed at low doses LMP744. Objective responses were documented for all indenoisoquinolines; efficacy (13/19 dogs) was greatest for LMP744. CONCLUSIONS: These results demonstrate proof-of-mechanism for indenoisoquinoline TOP1 inhibitors supporting their further clinical development. They also highlight the value of the NCI Comparative Oncology Program (https://ccr.cancer.gov/Comparative-Oncology-Program) for evaluating novel therapies in immunocompetent pets with cancers.


Assuntos
Antineoplásicos/farmacologia , Linfoma/tratamento farmacológico , Inibidores da Topoisomerase I/farmacologia , Animais , Antineoplásicos/química , Medula Óssea/efeitos dos fármacos , Ensaios Clínicos como Assunto , DNA Topoisomerases Tipo I/metabolismo , Modelos Animais de Doenças , Cães , Monitoramento de Medicamentos , Linfoma/metabolismo , Linfoma/patologia , Dose Máxima Tolerável , Terapia de Alvo Molecular , Inibidores da Topoisomerase I/química
20.
Steroids ; 99(Pt A): 103-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25159105

RESUMO

Estradiol (E2) in nipple aspirate fluid (NAF), ductal lavage fluid (DLF), and random fine needle aspirates (rFNA) are compared. Quantification was by immunoassay or tandem MS. The percent of women yielding NAF varied between 24% and 48% and for DLF was 86.3%. Variation between ducts within a breast was not less than variation between breasts within women but variation between breasts and within women over time was significantly less than variation between women. Serum E2 was highly significantly different among phases of the menstrual cycle but NAF E2 was not different. The correlation between serum and breast fluid E2 concentrations in premenopausal women had coefficients of determination of less than 15%. The correlation between serum and NAF in studies of postmenopausal women varied greatly and may depend on patient selection. The difference between NAF E2 between pre- and postmenopausal women was only 22%; for rFNA it was non-significantly 44% lower in a similar group of postmenopausal women. Progesterone was 96% and 98% lower in postmenopausal NAF and rFNA samples, respectively. Measurements of E2 in breast fluid or breast tissue appears to provide similar estimates of E2 exposure. E2 levels in breast fluid do not reflect the rapid changes that occur in serum and, thus, serum availability of E2 is only one factor determining its levels in the breast. The similarity of levels between breasts and between ducts suggests that estimates of estrogen exposure does not require multiple samples, however, unavailability of fluid may require rFNA in some cases.


Assuntos
Biópsia por Agulha Fina/métodos , Líquidos Corporais/química , Estrogênios/análise , Glândulas Mamárias Humanas/metabolismo , Líquidos Corporais/metabolismo , Estradiol/análise , Estradiol/sangue , Estradiol/metabolismo , Estrogênios/metabolismo , Feminino , Humanos , Imunoensaio/métodos , Glândulas Mamárias Humanas/química , Espectrometria de Massas/métodos , Fluido do Aspirado de Mamilo/química , Fluido do Aspirado de Mamilo/metabolismo , Controle de Qualidade
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