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2.
Cancer Med ; 9(20): 7537-7547, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32860335

RESUMEN

Real-world practice patterns and clinical outcomes in patients with follicular lymphoma (FL), including the adoption of maintenance rituximab (MR) therapy in the United States (US), have been reported in few studies since the release of the National LymphoCare Study almost a decade ago. We analyzed data from the largest integrated healthcare system in the United States, the Veterans Health Administration (VHA), to identify rates of adoption and effectiveness of MR in FL patients after first-line (1L) treatment. We identified previously untreated patients with FL in the VHA between 2006 and 2014 who achieved at least stable disease after chemoimmunotherapy or immunotherapy. Among these patients, those who initiated MR within 238 days of 1L composed the MR group, whereas those who did not were classified as the non-MR group. We examined the effect of MR on progression-free survival (PFS) and overall survival (OS). A total of 676 patients met our inclusion criteria, of whom 300 received MR. MR was associated with significant PFS (hazard ratio [HR]=0.55, P < .001) and OS (HR = 0.53, P = .005) compared to the non-MR group, after adjusting by age, sex, ethnicity, geographic region, diagnosis period, stage, grade at diagnosis, hemoglobin, lactate dehydrogenase (LDH), Charlson comorbidity index (CCI), 1L treatment regimen, and response to 1L treatment. These results suggest that in FL patients who do not experience disease progression after 1L treatment in real-world settings, MR is associated with a significant improvement in both PFS and OS. Maintenance therapy should be considered in FL patients who successfully complete and respond to 1L therapy.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Linfoma Folicular/tratamiento farmacológico , Linfoma Folicular/epidemiología , Rituximab/uso terapéutico , Salud de los Veteranos/estadística & datos numéricos , Veteranos , Anciano , Anciano de 80 o más Años , Antineoplásicos Inmunológicos/administración & dosificación , Antineoplásicos Inmunológicos/efectos adversos , Femenino , Humanos , Estimación de Kaplan-Meier , Linfoma Folicular/diagnóstico , Linfoma Folicular/mortalidad , Quimioterapia de Mantención , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Pronóstico , Rituximab/administración & dosificación , Rituximab/efectos adversos , Programa de VERF , Resultado del Tratamiento
3.
J Lesbian Stud ; 22(2): 185-203, 2018 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-28742445

RESUMEN

Inspired by Lynne Huffer's queer feminist genealogy, this article explores queer-trans-feminism as a project that would bring together queer, feminist, and transgender theory and politics into a shared critical lineage. I suggest that Monique Wittig is a neglected thinker who could re-enliven connections and debates within queer, feminist, and trans theory and politics. Utilizing recent historiographies of queer and feminist theory, I imagine what it would mean to hold on to the figure of the lesbian as a figure for queer-trans-feminist politics rather than render the lesbian anachronistic. I then explore the implications of Wittig's notion that "lesbians are not women" for a queer-trans-feminism. I argue that Wittig's critique of the language of the social sciences offers queer-trans-feminist scholars a source for contemporary self-critique and coalition.


Asunto(s)
Feminismo , Homosexualidad Femenina/psicología , Personas Transgénero/psicología , Femenino , Humanos , Literatura , Masculino , Teoría Psicológica , Minorías Sexuales y de Género
4.
Materials (Basel) ; 10(6)2017 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-28772998

RESUMEN

The microstructure of plastic bonded explosives (PBXs) is known to influence behavior during mechanical deformation, but characterizing the microstructure can be challenging. For example, the explosive crystals and binder in formulations such as PBX 9501 do not have sufficient X-ray contrast to obtain three-dimensional data by in situ, absorption contrast imaging. To address this difficulty, we have formulated a series of PBXs using octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) crystals and low-density binder systems. The binders were hydroxyl-terminated polybutadiene (HTPB) or glycidyl azide polymer (GAP) cured with a commercial blend of acrylic monomers/oligomers. The binder density is approximately half of the HMX, allowing for excellent contrast using in situ X-ray computed tomography (CT) imaging. The samples were imaged during unaxial compression using micro-scale CT in an interrupted in situ modality. The rigidity of the binder was observed to significantly influence fracture, crystal-binder delamination, and flow. Additionally, 2D slices from the segmented 3D images were meshed for finite element simulation of the mesoscale response. At low stiffness, the binder and crystal do not delaminate and the crystals move with the material flow; at high stiffness, marked delamination is noted between the crystals and the binder, leading to very different mechanical properties. Initial model results exhibit qualitatively similar delamination.

5.
Microsc Microanal ; 20(4): 1284-93, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24845035

RESUMEN

Meso-scale structure in polymeric foams determines the mechanical properties of the material. Density variations, even more than variations in the anisotropic void structure, can greatly vary the compressive and tensile response of the material. With their diverse use as both a structural material and space filler, polyurethane (PU) foams are widely studied. In this manuscript, quantitative measures of the density and anisotropic structure are provided by using micro X-ray computed tomography (microCT) to better understand the results of mechanical testing. MicroCT illustrates the variation in the density, cell morphology, size, shape, and orientation in different regions in blown foam due to the velocity profile near the casting surface. "Interrupted" in situ imaging of the material during compression of these sub-regions indicates the pathways of the structural response to the mechanical load and the changes in cell morphology as a result. It is found that molded PU foam has a 6 mm thick "skin" of higher density and highly eccentric morphological structure that leads to wide variations in mechanical performance depending upon sampling location. This comparison is necessary to understand the mechanical performance of the anisotropic structure.

6.
Soft Matter ; 10(8): 1142-50, 2014 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-24651451

RESUMEN

Here we report on the preparation and mechanical characterization of a 2-D self-assembled membrane formed by ionically crosslinking the polyelectrolyte parts of a gradient amphiphilic copolymer at oil and water interfaces. To fabricate these membranes, chloroform solutions of styrene-acrylic acid copolymers were suspended as pendant drops in an aqueous embedding phase. Due to the amphiphilic nature of these molecules, the copolymer chains migrate to the oil-water interface creating an interfacial layer. Upon the addition of zinc acetate to the embedding phase, crosslinks between copolymer molecules are formed via zinc-carboxylate complexes. While ionically crosslinked block copolymer membranes were critically damaged after one expansion cycle, ionically crosslinked gradient copolymers formed durable membranes that maintained their physical integrity through multiple expansion-compression-expansion cycles. This difference in mechanical behavior is attributed to the fact that gradient copolymers are more effective interfacial modifiers and have a significantly different molecular alignment at the oil-water interface. Additionally by changing the incubation time from 20 to 30 minutes, the low-strain dilatational modulus of these membranes was significantly increased due to higher interfacial coverage and crosslinking density. Longer incubation times also led to a distinct yield point and plastic deformation behavior at larger strains. Further mechanical characterization of the membranes showed that they can be quite robust and that by replacing the internal oil phase with an aqueous solution, future testing of membrane filtration and permeation may be possible.

7.
Rev Sci Instrum ; 83(7): 073308, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22852686

RESUMEN

We have developed and demonstrated a versatile, compact electron source that can produce a mono-energetic electron beam up to 50 mm in diameter from 0.1 to 30 keV with an energy spread of <10 eV. By illuminating a metal cathode plate with a single near ultraviolet light emitting diode, a spatially uniform electron beam with 15% variation over 1 cm(2) can be generated. A uniform electric field in front of the cathode surface accelerates the electrons into a beam with an angular divergence of <1° at 1 keV. The beam intensity can be controlled from 10 to 10(9) electrons cm(-2) s(-1).

8.
AIDS Patient Care STDS ; 25(4): 221-8, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21323566

RESUMEN

A key factor to the successful treatment of HIV is good adherence to antiretroviral therapy (ART). We developed a pharmacist-managed adherence clinic and designed a study to assess the impact of the adherence interventions by measuring the proportion of patients with 95% or greater adherence to ART before and after referral to the program. HIV providers referred patients with adherence problems to a pharmacist-managed adherence clinic. Interventions included scheduled clinic visits with the HIV Clinical Pharmacist and monthly refill reminders from pharmacy staff members over a 6-month period. Those aged 18-75, prescribed an ART regimen for a minimum of 3 months, and who filled their medications exclusively at the clinic pharmacy were eligible for study participation. The Proportion of Days Covered (PDC) served as a surrogate marker of overall adherence. A total of 34 patients were referred to the pharmacy clinic for adherence counseling, of whom 28 enrolled in the study. The proportion of participants with 95% or greater adherence to their ART regimen increased from 7% at baseline to 32% postintervention (p = 0.01). A subanalysis of the PDC revealed an overall increase from a baseline adherence mean of 60% to 81% postintervention (p < 0.0001). There was a notable trend toward an increase in the proportion of participants with an undetectable HIV-1 viral load (58-73%, baseline and postintervention, respectively, p = 0.10), but no statistically significant improvement in CD4 cell count. Clinical pharmacy interventions improved overall adherence to ART regimens in these patients with HIV.


Asunto(s)
Terapia Antirretroviral Altamente Activa , Prescripciones de Medicamentos/estadística & datos numéricos , Infecciones por VIH/tratamiento farmacológico , Cooperación del Paciente , Servicio de Farmacia en Hospital , Adolescente , Adulto , Anciano , Recuento de Linfocito CD4 , Monitoreo de Drogas , Femenino , Infecciones por VIH/virología , Hospitales Universitarios , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Derivación y Consulta , Distribución por Sexo , Adulto Joven
9.
Biomacromolecules ; 11(5): 1358-63, 2010 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-20392048

RESUMEN

Strain-stiffening behavior common to biopolymer networks is difficult to reproduce in synthetic networks. Physically associating synthetic polymer networks can be an exception to this rule and can demonstrate strain-stiffening behavior at relatively low values of strain. Here, the stiffening behavior of model elastic networks of physically associating triblock copolymers is characterized by shear rheometry. Experiments demonstrate a clear correlation between network structure and strain-stiffening behavior. Stiffening is accurately captured by a constitutive model with a single fitting parameter related to the midblock length. The same model is also effective for describing the stiffening of actin, collagen, and other biopolymer networks. Our synthetic polymer networks could be useful model systems for biological materials due to (1) the observed similarity in strain-stiffening behavior, which can be quantified and related to network structure, and (2) the tunable structure of the physically associating network, which can be manipulated to yield a desired response.


Asunto(s)
Biopolímeros/química
10.
Health Promot Pract ; 11(1): 104-11, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19098263

RESUMEN

Osteoporosis is a "pediatric disease with geriatric consequences." This article describes the development and pilot testing of an online system to educate high school students grades 9-12 about osteoporosis; an age where positive health changes could have long lasting effects. The intervention goal was to improve knowledge about osteoporosis and intent to adopt healthy bone practices. Online pre- and postintervention surveys evaluated participants' pre- and postintervention osteoporosis knowledge, attitudes, preventive practices, and postintervention intent to change healthy bone practices. Participants completed the Web-based program that provided detailed information about osteoporosis, and healthy bone practices, immediately after completing the pretest and just prior to completing the posttest. Eighty-nine students completed both the pre/posttests and were included in data analysis. Participants ranged in age from 13 to 17 and 75% were Caucasian (n = 65). Based on pre/posttest scores of 9 factual questions, students significantly improved their knowledge (p < .0001) and overall knowledge rating about osteoporosis at posttest (p < .001). Participants changed their perception regarding the disease's seriousness (p < .001), and considered adopting osteoporosis prevention practices. The study shows that an interactive educational Web site is an effective method for increasing awareness and understanding of osteoporosis in high school students.


Asunto(s)
Educación en Salud/métodos , Internet , Osteoporosis , Adolescente , Animales , Femenino , Humanos , Masculino , Leche , Soporte de Peso
11.
Rev Sci Instrum ; 79(10): 105104, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19044743

RESUMEN

We report the development of a fast position-sensitive laser beam detector. The detector uses a fiber-optic bundle that spatially splits the incident beam, followed by a fast balanced photodetector. The detector is applied to the study of Brownian motion of particles on fast time scales with 1 A spatial resolution. Future applications include the study of molecule motors, protein folding, as well as cellular processes.

12.
Am J Epidemiol ; 164(4): 358-66, 2006 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-16777931

RESUMEN

The hypothesized association between breast cancer and circadian disruption was evaluated in the Electromagnetic Fields and Breast Cancer on Long Island Study. Participants included 576 women with breast cancer diagnosed from August 1996 to June 1997 and 585 population-based controls (87% and 83% participation rates, respectively) aged < 75 years and living in the same Long Island, New York, home for > or = 15 years. An in-person interview ascertained light-at-night exposure histories through shift work (previous 15 years) and at home (previous 5 years). Odds ratios and 95% confidence intervals were estimated by unconditional multivariate logistic regression. Breast cancer was not associated with overall shift work (odds ratio (OR) = 1.04, 95% confidence interval (CI): 0.79, 1.38) or evening shift work (OR = 1.08, 95% CI: 0.81, 1.44). However, overnight shift workers were at lower risk than women never working shifts (OR = 0.55, 95% CI: 0.32, 0.94). Women who frequently turned on lights at home during sleep hours (> or = twice/week and > or = twice/night) had increased risks (OR = 1.65, 95% CI: 1.02, 2.69). The latter results suggest positive associations with residential light-at-night exposure, or they could reflect response biases. Furthermore, overall and evening shift work were not significant factors, and analyses of overnight shift workers yielded reduced risk estimates. The study thus provides mixed evidence for the light-at-night hypothesis.


Asunto(s)
Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Ritmo Circadiano , Iluminación/efectos adversos , Tolerancia al Trabajo Programado , Estudios de Casos y Controles , Campos Electromagnéticos/efectos adversos , Exposición a Riesgos Ambientales/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , New York/epidemiología , Características de la Residencia
13.
Epidemiology ; 14(5): 514-20, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14501265

RESUMEN

BACKGROUND: Exposure to electromagnetic fields (EMF) has been hypothesized to increase the risk of breast cancer by inhibiting the normal nocturnal rise in melatonin levels. METHODS: Information on electric blanket use was collected in a large, 2-stage, population-based, case-control investigation of breast cancer, The Long Island Breast Cancer Study Project (LIBCSP) and the EMF and Breast Cancer on Long Island Study (EBCLIS). The LIBCSP used a comprehensive questionnaire, including questions about electric appliance use, with responses available on 1354 cases diagnosed between mid-1996 and mid-1997 and 1426 control subjects. EBCLIS enrolled 576 cases and 585 control subjects who had participated in the LIBCSP and who had lived in their current homes for at least 15 years. EBCLIS participants were interviewed to obtain additional information on EMF exposures, including detailed questions on electric blanket use. RESULTS: Analyses of both the EBCLIS and the LIBCSP groups showed no association with breast cancer for ever-use of electric blankets, current or former use, use directly on the body, or use throughout the night in either pre- or postmenopausal women (range of adjusted odds ratios for ever vs. never use: 0.9-1.2). Furthermore, there was no trend in risk with increased duration of use, frequency of use, or other indicators of more intense exposure to EMF. Electric blanket use was not associated with hormone receptor status of the tumor. CONCLUSIONS: The results of this large investigation are consistent with those of most previous studies, and do not support the hypothesis that electric blanket use is associated with increased breast cancer risk.


Asunto(s)
Ropa de Cama y Ropa Blanca , Neoplasias de la Mama/etiología , Campos Electromagnéticos/efectos adversos , Anciano , Femenino , Humanos , Menopausia/fisiología , New York/epidemiología , Encuestas y Cuestionarios
14.
J Expo Anal Environ Epidemiol ; 13(4): 283-93, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12923555

RESUMEN

The Electromagnetic Fields and Breast Cancer on Long Island Study (EBCLIS) is a large population-based case-control study investigating possible associations between magnetic fields and breast cancer, and includes a comprehensive set of in-home measurements. We investigated the reproducibility of wire codes, their relation to 24-h measurements of residential magnetic fields, and potential influences, such as housing characteristics, in homes of the 1161 EBCLIS participants. Replicate wire coding was performed in homes originally categorized as having very high current configurations (VHCC) in the Wertheimer-Leeper (W-L) wire coding scheme, and a random sample of other homes (235 residences). Reproducibility was very high, with a kappa statistic of 0.83 (95% confidence interval (CI)=0.77-0.89) for the five-category W-L wire codes and 0.91 (95% CI=0.86-0.95) for the three-category Kaune-Savitz (K-S) codes. As levels of W-L and K-S wire codes increased, the mean and median 24-h levels of broadband and harmonic fields in the residences also increased, indicating an association between wire codes and magnetic fields measurements. Regions of Long Island with the highest percentage of homes built before 1950 had the highest percentage of higher current configuration homes, as well as the highest average 24-h broadband and harmonic measurements. Adjustment for age of the home and region did not affect the relation between wire codes and measured magnetic fields. Our results indicate that: (a). a high reproducibility in wire coding was achieved, (b). wire codes were correlated with magnetic fields, and (c). wire code levels were related to the age of the home. The high level of reproducibility suggests that, in our case-control analyses, there will be minimal bias due to misclassification of wire code categories. Results also suggest that wire codes are a proxy measure, to some degree, for current in-home magnetic field measurements in this study.


Asunto(s)
Neoplasias de la Mama/epidemiología , Instalación Eléctrica/clasificación , Campos Electromagnéticos/efectos adversos , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/métodos , Medición de Riesgo/métodos , Anciano , Neoplasias de la Mama/etiología , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/clasificación , Monitoreo Epidemiológico , Femenino , Vivienda , Humanos , Persona de Mediana Edad , New York , Reproducibilidad de los Resultados
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