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1.
Langmuir ; 40(18): 9529-9542, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38648374

RESUMEN

In this study, we systematically analyze the surface tension and Hansen solubility parameters (HSPs) of imidazolium-based ionic liquids (ILs) with different anions ([NTf2]-, [PF6]-, [I]-, and [Br]-). These anions are combined with the classical 1-alkyl-3-methyl-substituted imidazolium cations ([CnC1Im]+) and a group of oligoether-functionalized imidazolium cations ([(mPEGn)2Im]+) based on methylated polyethylene glycol (mPEGn). In detail, the influences of the length of the alkyl- and the mPEGn-chain, the anion size, and the water content are investigated experimentally. For [CnC1Im]+-based ILs, the surface tension decreases with increasing alkyl chain length in all cases, but the magnitude of this decrease depends on the size of the anion ([NTf2]- < [PF6]- < [Br]- ≤ [I]-). Molecular dynamics (MD) simulations on [CnC1Im]+-based ILs indicate that these differences are caused by the interplay of charged and uncharged domains, in particular in the different anions, which affects the ability of the alkyl chains of the cation to orient toward the liquid-gas interface. An increase in the mPEGn-chain length of the [(mPEGn)2Im][A] ILs does not significantly influence the surface tension. These changes upon variation of the cation/anion combination do not correlate with the evolution of the HSPs for the two sets of ILs. Finally, our data suggest that significant water contents up to water mole fractions of x(H2O) = 0.25 do not significantly affect the surface tension of the studied binary IL-water mixtures.

2.
Cancer ; 127(8): 1220-1227, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33508140

RESUMEN

BACKGROUND: Recent clinical trials support adding ovarian suppression (OS) to oral endocrine therapy (ET) for premenopausal women with early breast cancer. The adoption of OS among real-world populations and the impact of OS on ET adherence have not been evaluated. METHODS: This study examined a retrospective, observational cohort of women under the age of 50 years with incident early breast cancer from 2001 to 2016. The IBM MarketScan Commercial insurance claims database was used to identify new users of ET with or without OS and to track discontinuation of or adherence to ET. In all, 21,948 women filled at least 1 prescription for ET within 12 months of their diagnosis after a washout period of 12 months with no prior claims. Patients who received an aromatase inhibitor without a synchronous OS drug were excluded. RESULTS: Use of OS increased over time and reached 11.3% in 2016. In an unadjusted analysis, 40.2% of ET+OS users discontinued ET early, whereas 48.8% of tamoxifen-alone users did. In adjusted analyses, ET+OS users had a similar likelihood of discontinuing ET in comparison with tamoxifen-alone users (hazard ratio, 0.92; 95% confidence interval, 0.83-1.03). Approximately 30% of women had low adherence over the first year of use. The likelihood of high adherence was similar, regardless of OS exposure. CONCLUSIONS: The use of OS among young, commercially insured patients with breast cancer increased over time in agreement with recent clinical trial results but remained relatively low. Nonadherence to ET was common, but the use of OS was not associated with lower adherence to ET in this observational, nonrandomized cohort. These findings may reassure oncologists that use of OS does not endanger ET adherence, although prospective studies are needed for confirmation.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Cumplimiento de la Medicación/estadística & datos numéricos , Adulto , Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/patología , Bases de Datos Factuales , Prescripciones de Medicamentos/estadística & datos numéricos , Femenino , Humanos , Persona de Mediana Edad , Premenopausia , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Tamoxifeno/uso terapéutico
3.
Cancer ; 125(22): 3985-3992, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31398265

RESUMEN

BACKGROUND: After controlling for baseline disease factors, researchers have found that black women have worse breast cancer survival, and this suggests that treatment differences may contribute to poorer outcomes. Delays in initiating and completing treatment are one proposed mechanism. METHODS: Phase 3 of the Carolina Breast Cancer Study involved a large, population-based cohort of women with incident breast cancer. For this analysis, we included black women (n = 1328) and white women (n = 1331) with stage I to III disease whose treatment included surgery with or without adjuvant therapies. A novel treatment pathway grouping was used to benchmark the treatment duration (surgery only, surgery plus chemotherapy, surgery plus radiation, or all 3). Models controlled for the treatment pathway, age, and tumor characteristics and for demographic factors related to health care access. Exploratory analyses of the association between delays and cancer recurrence were performed. RESULTS: In fully adjusted analyses, blacks had 1.73 times higher odds of treatment initiation more than 60 days after their diagnosis in comparison with whites (odds ratio [OR], 1.73; 95% confidence interval [CI], 1.04-2.90). Black race was also associated with a longer treatment duration. Blacks were also more likely to be in the highest quartile of treatment duration (OR, 1.69; 95% CI, 1.41-2.02), even after adjustments for demographic and tumor characteristics (OR, 1.31; 95% CI, 1.04-1.64). A nonsignificant trend toward a higher recurrence risk was observed for patients with delayed initiation (hazard ratio, 1.44; 95% CI, 0.89-2.33) or the longest duration (hazard ratio, 1.17; 95% CI, 0.87-1.59). CONCLUSIONS: Black women more often had delayed treatment initiation and a longer duration than whites receiving similar treatment. Interventions that target access barriers may be needed to improve timely delivery of care.


Asunto(s)
Neoplasias de la Mama/epidemiología , Continuidad de la Atención al Paciente , Etnicidad , Disparidades en Atención de Salud , Tiempo de Tratamiento , Adulto , Anciano , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/etnología , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , North Carolina/epidemiología , Pronóstico
4.
Cancer Causes Control ; 30(1): 103-112, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30542984

RESUMEN

PURPOSE: Tamoxifen is widely used to reduce the risk of breast cancer (BC) recurrence and extend disease-free survival among women with estrogen-sensitive breast cancers. Tamoxifen efficacy is thought to be attributable to its active metabolite, which is formed through a reaction catalyzed by the P450 enzyme, CYP2D6. Inhibition of tamoxifen metabolism as a result of germline genetic variation and/or use of CYP2D6-inhibiting medications ("inhibitors") is hypothesized to increase the risk of adverse BC outcomes among women taking tamoxifen. METHODS: The present cohort study of 960 women diagnosed with early-stage BC between 1993 and 1999 examined the association between concomitant use of CYP2D6 inhibitors and adjuvant tamoxifen and the risk of adverse BC outcomes (recurrence, second primary BC, BC mortality), both overall and according to CYP2D6 metabolic phenotype. RESULTS: Six or more months of CYP2D6 inhibitor use concomitant with tamoxifen was not associated with any appreciable increase in risk of recurrence or second primary BC or BC mortality, and there was no clear evidence of variation by CYP2D6 metabolic phenotype. CONCLUSIONS: These results are consistent with the relatively few other large, population-based studies conducted to date that have not observed an increased risk of adverse BC outcomes associated with CYP2D6 inhibition.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Citocromo P-450 CYP2D6/genética , Tamoxifeno/uso terapéutico , Anciano , Neoplasias de la Mama/genética , Estudios de Cohortes , Inhibidores del Citocromo P-450 CYP2D6/farmacología , Supervivencia sin Enfermedad , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Fenotipo
5.
Med Care ; 57(4): 286-294, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30789540

RESUMEN

BACKGROUND: Multiple claims-based proxy measures of poor function have been developed to address confounding in observational studies of drug effects in older adults. We evaluated agreement between these measures and their associations with treatment receipt and mortality in a cohort of older colon cancer patients. METHODS: Medicare beneficiaries age 66+ diagnosed with stage II-III colon cancer were identified in the Surveillance, Epidemiology, and End Results-Medicare database (2004-2011). Poor function was operationalized by: (1) summing the total poor function indicators for each model; and (2) estimating predicted probabilities of poor function at diagnosis. Agreement was evaluated using Fleiss' κ and Spearman's correlation. Associations between proxy measures and: (1) laparoscopic versus open surgery; (2) chemotherapy versus none; (3) 5-fluorouracil (5FU)+oxaliplatin (FOLFOX) versus 5FU monotherapy; and (4) 1-year mortality were estimated using log-binomial regression, controlling for age, sex, stage, and comorbidity. Survival estimates were stratified by functional group, age, and comorbidity. RESULTS: Among 29,687 eligible colon cancer patients, 67% were 75+ years and 45% had stage III disease. Concordance across the poor function indicator counts was moderate (κ: 0.64) and correlation of predicted probability measures varied (ρ: 0.21-0.74). Worse function was associated with lower chemotherapy and FOLFOX receipt, and higher 1-year mortality. Within age and comorbidity strata, poor function remained associated with mortality. CONCLUSIONS: While agreement varied across the claims-based proxy measures, each demonstrated anticipated associations with treatment receipt and mortality independent of comorbidity. Claims-based comparative effectiveness studies in older populations should consider applying one of these models to improve confounding control.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Quimioterapia Adyuvante , Neoplasias del Colon/mortalidad , Resultado del Tratamiento , Anciano , Anciano de 80 o más Años , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante/métodos , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Comorbilidad , Femenino , Fluorouracilo/administración & dosificación , Humanos , Revisión de Utilización de Seguros , Masculino , Medicare , Oxaliplatino/administración & dosificación , Programa de VERF , Estados Unidos
6.
Clin Epidemiol ; 14: 737-748, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35677476

RESUMEN

Background: Routine monitoring of low-density lipoprotein cholesterol (LDL-C) identifies patients who may benefit from modifying lipid-lowering therapies (LLT). However, the extent to which LDL-C testing is occurring in clinical practice is unclear, specifically among patients hospitalized for a myocardial infarction (MI). Methods: Using US commercial claims data, we identified patients with an incident MI hospitalization between 01/01/2008-03/31/2019. LDL-C testing was assessed in the year before admission (pre-MI) and the year after discharge (post-MI). Changes in LDL-C testing were evaluated using a Poisson model fit to pre-MI rates and extrapolated to the post-MI period. We predicted LDL-C testing rates if no MI had occurred (ie, based on pre-MI trends) and estimated rate differences and ratios (contrasting observed vs predicted rates). Results: Overall, 389,367 patients were hospitalized for their first MI during the study period. In the month following discharge, 9% received LDL-C testing, increasing to 27% at 3 months and 52% at 12 months. Mean rates (tests per 1000 patients per month) in the pre- and post-MI periods were 51.9 (95% CI: 51.7, 52.1) and 84.4 (95% CI: 84.1, 84.6), respectively. Over 12 months post-MI, observed rates were higher than predicted rates; the maximum rate difference was 66 tests per 1000 patients in month 2 (rate ratio 2.2), stabilizing at a difference of 15-20 (ratio 1.2-1.3) for months 6-12. Conclusion: Although LDL-C testing increased following MI hospitalization, rates remained lower than recommended by clinical guidelines. This highlights a potential gap in care, where increased LDL-C testing after MI may provide opportunities for LLT modification and decrease risk of subsequent cardiovascular events.

7.
Sci Adv ; 8(46): eade3262, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36383668

RESUMEN

The observable reaction rate of heterogeneously catalyzed reactions is known to be limited either by the intrinsic kinetics of the catalytic transformation or by the rate of pore and/or film diffusion. Here, we show that in gas generation reactions from liquid reactants, the nucleation of gas bubbles in the catalyst pore structure represents an additional important rate-limiting step. This is highlighted for the example of catalytic hydrogen release from the liquid organic hydrogen carrier compound perhydro-dibenzyltoluene. A nucleation-inhibited catalytic system produces only dissolved hydrogen with fast saturation of the fluid phase around the active site, while bubble formation enhances mass transfer by more than a factor of 50 in an oscillating reaction regime. Nucleation can be efficiently triggered not only by temperature changes and catalyst surface modification but also by a mechanical stimulus. Our work sheds new light on performance-limiting factors in reactions that are of highest relevance for the future green hydrogen economy.

8.
Carbohydr Polym ; 272: 118506, 2021 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-34420752

RESUMEN

Biobased and biodegradable films were prepared by physically mixing 2,3-dialdehyde cellulose (DAC) with two other biopolymers, zein and gelatin, in three different proportions. The antimicrobial activities of the composite blends against Gram-positive and Gram-negative bacteria increase with the increase of DAC content. Cell viability tests on mammalian cells showed that the materials were not cytotoxic. In addition, DAC and gelatin were able to promote thermal degradation of the blends. However, DAC increased the stiffness and decreased the glass transition temperature of the blends, while gelatin was able to decrease the stiffness of the film. Morphological analysis showed the effect of DAC on the surface smoothness of the blends. The contact angle confirmed that all blends were within the range of hydrophilic materials. Although all the blends showed impressive performance for wound dressing application, the blend with gelatin might be more suitable for this purpose due to its better mechanical performance and antibacterial activity.


Asunto(s)
Antibacterianos , Vendajes , Interacciones Hidrofóbicas e Hidrofílicas , Pruebas de Sensibilidad Microbiana , Resistencia a la Tracción
9.
J Clin Med ; 9(5)2020 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-32354003

RESUMEN

Temporal muscle thickness (TMT) was investigated as a novel surrogate marker on MRI examinations of the brain, to detect patients who may be at risk for sarcopenia. TMT was analyzed in a retrospective, normal collective cohort (n = 624), to establish standard reference values. These reference values were correlated with grip strength measurements and body mass index (BMI) in 422 healthy volunteers and validated in a prospective cohort (n = 130) of patients with various neurological disorders. Pearson correlation revealed a strong association between TMT and grip strength (retrospective cohort, ρ = 0.746; p < 0.001; prospective cohort, ρ = 0.649; p < 0.001). A low or no association was found between TMT and age (retrospective cohort, R2 correlation coefficient 0.20; p < 0.001; prospective cohort, ρ = -0.199; p = 0.023), or BMI (retrospective cohort, ρ = 0.116; p = 0.042; prospective cohort, ρ = 0.227; p = 0.009), respectively. Male patients with temporal wasting and unintended weight loss, respectively, showed significantly lower TMT values (p = 0.04 and p = 0.015, unpaired t-test). TMT showed a high correlation with muscle strength in healthy individuals and in patients with various neurological disorders. Therefore, TMT should be integrated into the diagnostic workup of neurological patients, to prevent, delay, or treat sarcopenia.

10.
JNCI Cancer Spectr ; 2(1): pky001, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31355356

RESUMEN

BACKGROUND: Postmenopausal bone fracture's have been proposed as a marker of lifetime estrogen exposure and have been associated with decreased risk of breast and endometrial cancer. It is plausible that prediagnostic fractures may be related to survival of estrogen-sensitive cancers. METHODS: We evaluated a cohort of breast (n = 6411), endometrial (n = 1127), and ovarian (n = 658) cancer cases diagnosed between 1992 and 2010 while participating in the Women's Health Initiative. Postmenopausal fracture history was assessed from baseline reports of fractures after age 55 years and incident fractures that occurred at least one year prior to cancer diagnosis during study follow-up. Using Cox regression, we compared women with and without a history of fractures with respect to overall and cancer-specific survival. Estimates were adjusted for participant factors, including hormone therapy use; hormone receptor status was not included in our analysis. RESULTS: Among women with breast cancer, a history of prediagnostic fractures at any site was associated with poorer overall survival (hazard ratio [HR] = 1.22, 95% confidence interval [CI] = 1.05 to 1.43). A history of hip, forearm, or spine fractures, or hip fracture alone, was associated with increased risk of mortality (HR = 1.26, 95% CI = 1.01 to 1.58, and HR = 2.05, 95% CI = 1.27 to 3.32, respectively). Fracture history was associated neither with cancer-specific survival among breast cancer survivors, nor with overall or disease-specific mortality among endometrial and ovarian cancer survivors. CONCLUSIONS: Postmenopausal breast cancer patients with a history of fractures, especially of the hip, are more likely to die of any cause than breast cancer survivors without a fracture history. Identifying and intervening in fracture risk factors should be standard of care for all women diagnosed with breast cancer.

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