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1.
Environ Sci Technol ; 51(15): 8757-8762, 2017 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-28661662

RESUMEN

The Deepwater Horizon (DWH) oil spill resulted in the release of millions of barrels of oil into the Gulf of Mexico, and some marsh shorelines experienced heavy oiling including vegetation laid over under the weight of oil. Periwinkle snails (Littoraria irrorata) are a critical component of these impacted habitats, and population declines following oil spills, including DWH, have been documented. This study determined the effects of oil on marsh periwinkle movement and survivorship following exposure to oil. Snails were placed in chambers containing either unoiled or oiled laid over vegetation to represent a heavily impacted marsh habitat, with unoiled vertical structure at one end. In the first movement assay, snail movement to standing unoiled vegetation was significantly lower in oiled chambers (oil thickness ≈ 1 cm) compared to unoiled chambers, as the majority (∼75%) of snails in oiled habitats never reached standing unoiled vegetation after 72 h. In a second movement assay, there was no snail movement standing unoiled structure in chambers with oil thicknesses of 0.1 and 0.5 cm, while 73% of snails moved in unoiled chambers after 4h. A toxicity assay was then conducted by exposing snails to oil coated Spartina stems in chambers for periods up to 72 h, and mortality was monitored for 7 days post exposure. Snail survival decreased with increasing exposure time, and significant mortality (∼35%) was observed following an oil exposure of less than 24 h. Here, we have shown that oil impeded snail movement to clean habitat over a short distance and resulted in oil-exposure times that decreased survival. Taken together, along with declines documented by others in field surveys, these results suggest that marsh periwinkle snails may have been adversely affected following exposure to DWH oil.


Asunto(s)
Distribución Animal , Movimiento , Contaminación por Petróleo/efectos adversos , Caracoles , Animales , Ecosistema , Golfo de México , Dinámica Poblacional , Vinca , Humedales
2.
Gastroenterology ; 149(1): 119-29, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25836985

RESUMEN

BACKGROUND & AIMS: Despite the significant association between obesity and several cancers, it has been difficult to establish an association between obesity and hepatocellular carcinoma (HCC). Patients with HCC often have ascites, making it a challenge to determine body mass index (BMI) accurately, and many factors contribute to the development of HCC. We performed a case-control study to investigate whether obesity early in adulthood affects risk, age of onset, or outcomes of patients with HCC. METHODS: We interviewed 622 patients newly diagnosed with HCC from January 2004 through December 2013, along with 660 healthy controls (frequency-matched by age and sex) to determine weights, heights, and body sizes (self-reported) at various ages before HCC development or enrollment as controls. Multivariable logistic and Cox regression analyses were performed to determine the independent effects of early obesity on risk for HCC and patient outcomes, respectively. BMI was calculated, and patients with a BMI of 30 kg/m(2) or greater were considered obese. RESULTS: Obesity in early adulthood (age, mid-20s to mid-40s) is a significant risk factor for HCC. The estimated odds ratios were 2.6 (95% confidence interval [CI], 1.4-4.4), 2.3 (95% CI, 1.2-4.4), and 3.6 (95% CI, 1.5-8.9) for the entire population, for men, and for women, respectively. Each unit increase in BMI at early adulthood was associated with a 3.89-month decrease in age at HCC diagnosis (P < .001). Moreover, there was a synergistic interaction between obesity and hepatitis virus infection. However, we found no effect of obesity on the overall survival of patients with HCC. CONCLUSIONS: Early adulthood obesity is associated with an increased risk of developing HCC at a young age in the absence of major HCC risk factors, with no effect on outcomes of patients with HCC.


Asunto(s)
Envejecimiento , Índice de Masa Corporal , Carcinoma Hepatocelular/epidemiología , Neoplasias Hepáticas/epidemiología , Obesidad/epidemiología , Adulto , Edad de Inicio , Anciano , Envejecimiento/metabolismo , Envejecimiento/patología , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/fisiopatología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven
3.
Oncotarget ; 9(102): 37721-37732, 2018 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-30701027

RESUMEN

Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) play critical roles in angiogenesis in hepatocellular carcinoma (HCC). In addition, recent data suggest that Ang-1/Ang-2 are involved in regulating the immune response. The aim of our study was to explore the clinical prognostic significance of plasma Ang-1 and Ang-2 in HCC. We prospectively enrolled and collected data and blood samples from 767 HCC patients treated at MD Anderson Cancer Center between 2001 and 2014. Controls consisted of cirrhotic patients (n = 75) and healthy volunteers (n = 200). The cutoff value was the median level of each angiogenic factor. Overall survival (OS) was estimated by Kaplan-Meier curves and compared by the log-rank test. Higher plasma Ang-2 was significantly associated with advanced clinicopathologic features of advanced HCC and lower OS. Median OS was 61.8 months (95% confidence interval [CI], 45.1-78.5 months) for low Ang-2 compared with 28.5 months (95% CI, 24.8-32.1 months) for high Ang-2 (p < 0.001). In contrast, higher Ang-1 was associated with longer OS. Median OS was 37.2 months (95% CI, 31.0-43.4 months) for high Ang-1 compared with 26.2 months (95% CI, 22.2-30.3 months) for those with low Ang-1 (p = 0.043). In conclusion, our findings indicate that plasma Ang-1 and Ang-2 levels are potential diagnostic and prognostic biomarkers in HCC.

4.
Toxicol Sci ; 92(1): 23-32, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16687392

RESUMEN

The use of nanotechnology in consumer and industrial applications will likely have a profound impact on a number of products from a variety of industrial sectors. Nanomaterials exhibit unique physical/chemical properties and impart enhancements to engineered materials, including better magnetic properties, improved electrical activity, and increased optical properties. The United States, Europe, and Japan have each initiated comprehensive programs to promote and expand the utility of nanotechnology for commercial applications. An important component of these programs is the development of reliable risk and safety evaluations for these materials to ensure their safety for human health and the environment. The scope of each of these programs includes efforts to assess the hazards posed by nanomaterials in realistic exposure conditions.


Asunto(s)
Cooperación Internacional , Nanotecnología , Medición de Riesgo , Seguridad , Humanos
5.
J Med Chem ; 58(5): 2326-49, 2015 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-25643210

RESUMEN

High throughput screening followed by a lead generation campaign uncovered a novel series of urea containing morpholinopyrimidine compounds which act as potent and selective dual inhibitors of mTORC1 and mTORC2. We describe the continued compound optimization campaign for this series, in particular focused on identifying compounds with improved cellular potency, improved aqueous solubility, and good stability in human hepatocyte incubations. Knowledge from empirical SAR investigations was combined with an understanding of the molecular interactions in the crystal lattice to improve both cellular potency and solubility, and the composite parameters of LLE and pIC50-pSolubility were used to assess compound quality and progress. Predictive models were employed to efficiently mine the attractive chemical space identified resulting in the discovery of 42 (AZD3147), an extremely potent and selective dual inhibitor of mTORC1 and mTORC2 with physicochemical and pharmacokinetic properties suitable for development as a potential clinical candidate.


Asunto(s)
Descubrimiento de Drogas , Hepatocitos/efectos de los fármacos , Complejos Multiproteicos/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/química , Pirimidinas/farmacología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Tiourea/análogos & derivados , Células Cultivadas , Hepatocitos/citología , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Diana Mecanicista del Complejo 2 de la Rapamicina , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad , Tiourea/química , Tiourea/farmacología
6.
J Med Chem ; 56(5): 2059-73, 2013 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-23394218

RESUMEN

Wide-ranging exploration of analogues of an ATP-competitive pyrrolopyrimidine inhibitor of Akt led to the discovery of clinical candidate AZD5363, which showed increased potency, reduced hERG affinity, and higher selectivity against the closely related AGC kinase ROCK. This compound demonstrated good preclinical drug metabolism and pharmacokinetics (DMPK) properties and, after oral dosing, showed pharmacodynamic knockdown of phosphorylation of Akt and downstream biomarkers in vivo, and inhibition of tumor growth in a breast cancer xenograft model.


Asunto(s)
Inhibidores de Proteínas Quinasas/síntesis química , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Pirimidinas/síntesis química , Pirroles/síntesis química , Administración Oral , Línea Celular Tumoral , Femenino , Humanos , Concentración 50 Inhibidora , Modelos Moleculares , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Pirroles/farmacología , Relación Estructura-Actividad , Ensayos Antitumor por Modelo de Xenoinjerto
10.
J Chem Inf Comput Sci ; 43(2): 346-56, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12653496

RESUMEN

Reduced graphs provide summary representations of chemical structures. Here, a variety of different types of reduced graphs are compared in similarity searches. The reduced graphs are found to give comparable performance to Daylight fingerprints in terms of the number of active compounds retrieved. However, no one type of reduced graph is found to be consistently superior across a variety of different data sets. Consequently, a representative set of reduced graphs was chosen and used together with Daylight fingerprints in data fusion experiments. The results show improved performance in 10 out of 11 data sets compared to using Daylight fingerprints alone. Finally, the potential of using reduced graphs to build SAR models is demonstrated using recursive partitioning. An SAR model consistent with a published model is found following just two splits in the decision tree.


Asunto(s)
Gestión de la Información , Preparaciones Farmacéuticas/química , Farmacología/métodos , Presentación de Datos , Diseño de Fármacos , Estructura Molecular , Relación Estructura-Actividad
11.
Cancer ; 100(11): 2347-54, 2004 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-15160337

RESUMEN

BACKGROUND: Patients with localized esophageal carcinoma often develop locoregional and distant disease recurrence. The current study investigated the outcome of a new chemotherapy combination as induction therapy before chemoradiotherapy. METHODS: Forty-three patients with resectable carcinoma of the esophagus or gastroesophageal junction were enrolled. Most of the tumors were endoscopic ultrasonography (EUS) (EUS)T3 (84%) and (EUS)N1 (63%). The patients received < or = 2 6-week cycles of CPT-11 and cisplatin followed by chemoradiotherapy (45 grays with 5-fluorouracil and paclitaxel). Five to six weeks after chemoradiotherapy, the patients underwent staging and surgery. The feasibility, curative resection rates, overall and disease-free survival rates, rate of significant pathologic response, and patterns of disease recurrence were assessed. RESULTS: Of the 43 patients, 39 (91%) underwent an R0 resection. Two patients (5%) died after surgery. A pathologic complete response (pathCR) was observed in 11 (28%) of the 39 patients (or 26% of the 43 patients). In addition, 16 patients (41% of 39 patients or 37% of 43 patients) had < 10% viable tumor in the surgical specimen (pathPR). A comparison of endoscopic ultrasonograpy T and N classifications with surgical T and N classifications demonstrated significant down-staging (P < 0.01). The median survival period of all 43 patients was 22.1 months. Patients who had achieved a pathCR or pathPR had a longer median survival (25.6 months) than those who achieved less than a pathPR (18.5 months; P = 0.52). None of the clinical parameters examined were found to correlate with survival or pathologic response. CONCLUSIONS: CPT-11-based induction chemotherapy resulted in substantial pathCR and pathPR rates, both of which lead to a favorable survival outcome. The three-step strategy needs to be developed further, with the investigation of targeted therapies with chemotherapy and radiotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Camptotecina/análogos & derivados , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/radioterapia , Unión Esofagogástrica/patología , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/radioterapia , Adenocarcinoma/cirugía , Adulto , Anciano , Camptotecina/administración & dosificación , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirugía , Cisplatino/administración & dosificación , Terapia Combinada , Endosonografía , Neoplasias Esofágicas/cirugía , Unión Esofagogástrica/cirugía , Estudios de Factibilidad , Femenino , Fluorouracilo/administración & dosificación , Humanos , Irinotecán , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/radioterapia , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Paclitaxel/administración & dosificación , Cuidados Preoperatorios , Pronóstico , Inducción de Remisión , Tasa de Supervivencia
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