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1.
AIDS Behav ; 25(10): 3057-3073, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33830327

RESUMEN

Pre-exposure prophylaxis (PrEP) is an effective form of HIV prevention, but young sexual minority men face myriad barriers to PrEP uptake. Participants (n = 202) completed a survey on healthcare experiences and beliefs about HIV and PrEP. While 98% of the sample knew about PrEP, only 23.2% reported currently taking PrEP. Participants were more likely to be taking PrEP if they received PrEP information from a healthcare provider and endorsed STI-related risk compensation. Conversely, PrEP uptake was less likely among those with concerns about medication use and adherence. While there were no racial/ethnic differences in PrEP uptake, there were differences in correlates of PrEP use for White participants and participants of color. To facilitate PrEP uptake, clinicians should provide PrEP education and screen all patients for PrEP candidacy. Additionally, public health messaging must reframe HIV "risk", highlight benefits of STI testing, and emphasize the importance of preventive healthcare for SMM.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Personas Transgénero , Fármacos Anti-VIH/uso terapéutico , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Humanos , Masculino , Ciudad de Nueva York
2.
J HIV AIDS Soc Serv ; 19(2): 173-187, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-35431666

RESUMEN

Antiretroviral-related treatment fatigue is inconsistently defined in the literature on barriers to ART adherence. Research suggests that treatment fatigue is a salient challenge for people struggling with antiretroviral therapy adherence, but little is known about how people living with HIV attempt to manage this fatigue. Twenty-seven semi-structured interviews were conducted with low-income people of color living with HIV in NYC that were currently, or recently, disengaged from HIV care. The findings from this exploratory study suggest that treatment fatigue was common and that participants devised personal strategies to overcome it. These strategies included using reminder programs, requesting weekly rather than monthly pill quantities, and taking "pill holidays". The varied nature- and varying levels of effectiveness- of these strategies highlight the need for specific programming to provide tailored support. Future research should examine treatment fatigue as a specific subtype of adherence challenge, and aim to define pill fatigue clearly.

3.
Neurobiol Aging ; 22(4): 677-82, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11445268

RESUMEN

Ubiquitin and alpha B-crystallin belong to a class of proteins which are overexpressed in a variety of human neuropathological conditions associated with increased cellular stress. In this study we have examined the brains of aged rhesus monkeys (Macaca mulatta; n = 10, mean age: 29.7 years) using antibodies against the stress proteins ubiquitin, alpha B-crystallin, and heat shock protein 27 (hsp27). Here, we demonstrate an increased expression of ubiquitin, alpha B-crystallin, and hsp27 in spheroid bodies predominantly localized in the globus pallidus and pars reticulata of the substantia nigra. A portion of the pallido-nigral spheroids also contained ferric iron as highlighted by Perls' staining. On the basis of these findings we advance the hypothesis that expression of ubiquitin, alpha B-crystallin, and hsp27 in pallido-nigral spheroids of aged rhesus monkeys represents a stress response possibly related to increased iron-mediated oxidative stress.


Asunto(s)
Envejecimiento/metabolismo , Cristalinas/biosíntesis , Globo Pálido/metabolismo , Proteínas de Neoplasias/biosíntesis , Sustancia Negra/metabolismo , Ubiquitinas/biosíntesis , Envejecimiento/patología , Animales , Cristalinas/análisis , Femenino , Globo Pálido/química , Globo Pálido/patología , Inmunohistoquímica , Hierro/análisis , Macaca mulatta , Masculino , Proteínas de Neoplasias/análisis , Estrés Oxidativo , Neurodegeneración Asociada a Pantotenato Quinasa/metabolismo , Neurodegeneración Asociada a Pantotenato Quinasa/patología , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/patología , Sustancia Negra/química , Sustancia Negra/patología , Ubiquitinas/análisis
4.
J Appl Behav Anal ; 33(4): 635-8, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11214040

RESUMEN

Senior drivers are vulnerable to automobile crashes and subsequent injury and death. Safety belts reduce health risks associated with auto crashes. Therefore, it is important to encourage senior drivers to wear safety belts while driving. Using an AB design, replicated five times, we evaluated the short- and long-term effects of a sign with the message "BUCKLE UP, STAY SAFE" attached to a stop sign at the exits of five different senior communities. Safety belt use was stable during two pretreatment assessments averaged across the five sites and 250 drivers (72% and 68% usage), but significantly increased following installation of these signs (94% usage). Six months after installation of the signs, the effect persisted (88% usage). Use of such signs may be a cost-effective way of promoting safety belt use.


Asunto(s)
Conducción de Automóvil , Motivación , Seguridad , Cinturones de Seguridad/estadística & datos numéricos , Accidentes de Tránsito/prevención & control , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad
5.
J Biomed Opt ; 4(4): 450-8, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23014618

RESUMEN

This paper presents a comparison of in vivo optical coherence tomography (OCT) captured cataract images to subsequent histopathological examination of the lenticular opacities. OCT imaging was performed on anesthetized Rhesus monkeys, known as the delayed effects colony (DEC), with documented cataracts. These monkeys were exposed to several types of radiation during the mid and late 1960s. The radiation and age related cataracts in these animals were closely monitored using a unique grading system developed specifically for the DEC. In addition to this system, a modified version of a common cataract grading scheme for use in humans was applied. Of the original 18 monkeys imaged, lenses were collected at necropsy from seven of these animals, processed, and compared to OCT images. Results showed a direct correlation between the vertical OCT images and the cataractous lesions seen on corresponding histopathologic sections of the lenses. Based on the images obtained and their corresponding documented comparison to histopathology, OCT showed tremendous potential to aid identification and characterization of cataracts. There can be artifactual problems with the images related to movement and shadows produced by opacities. However, with the advent of increased speed in imaging and multiplanar imaging, these disadvantages may easily be overcome. © 1999 Society of Photo-Optical Instrumentation Engineers.

9.
Int J Radiat Biol ; 70(3): 309-18, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8800202

RESUMEN

Chromosome translocations are persistent indicators of prior exposure to ionizing radiation and the development of 'chromosome painting' to efficiently detect translocations has resulted in a powerful biological dosimetry tool for radiation dose reconstruction. However, the actual stability of the translocation frequency with time after exposure must be measured before it can be used reliably to obtain doses for individuals exposed years or decades previously. Human chromosome painting probes were used here to measure reciprocal translocation frequencies in cells from two tissues of 8 rhesus monkeys (Macaca mulatta) irradiated almost three decades previously. Six of the monkeys were exposed in 1965 to whole-body (fully penetrating) radiation and two were unexposed controls. The primates were irradiated as juveniles to single doses of 0.56, 1.13, 2.00, or 2.25 Gy. Blood lymphocytes (and skin fibroblasts from one individual) were obtained for cytogenetic analysis in 1993, near the end of the animals' lifespans. Results show identical dose-response relationships 28 y after exposure in vivo and immediately after exposure in vitro. Because chromosome aberrations are induced with identical frequencies in vivo and in vitro, these results demonstrate that the translocation frequencies induced in 1965 have not changed significantly during the almost three decades since exposure. Finally, our emerging biodosimetry data for individual radiation workers are now confirming the utility of reciprocal translocations measured by FISH in radiation dose reconstruction.


Asunto(s)
Translocación Genética , Irradiación Corporal Total , Animales , Células Cultivadas , Relación Dosis-Respuesta en la Radiación , Humanos , Macaca mulatta , Fotones , Rayos X
10.
Acta Astronaut ; 32(11): 739-48, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11538452

RESUMEN

Recognition of the human risks from radiation exposure during manned missions in deep space has been fostered by international co-operation; interagency collaboration is facilitating their evaluation. Further co-operation can lead, perhaps by the end of this decade, to an evaluation of one of the three major risks, namely radiation cataractogenesis, sufficient for use in the planning of the manned mission to Mars.


Asunto(s)
Catarata/epidemiología , Radiación Cósmica/efectos adversos , Cristalino/efectos de la radiación , Protones , Sistema Solar , Vuelo Espacial , Aluminio/normas , Animales , Catarata/etiología , Modelos Animales de Enfermedad , Perros , Europa (Continente) , Humanos , Cooperación Internacional , Transferencia Lineal de Energía , Macaca mulatta , Marte , Conejos , Dosis de Radiación , Protección Radiológica/normas , Ratas , Ratas Endogámicas F344 , Medición de Riesgo , Estados Unidos , United States National Aeronautics and Space Administration
11.
Int J Radiat Biol ; 66(4): 381-4, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7930840

RESUMEN

The mitogen phytohemagglutinin (PHA) works well in both human and cynomolgus monkey (Macaca fascicularis) lymphocyte cultures to stimulate T cell proliferation. T cells from rhesus monkeys (Macaca mulatta) are less responsive than human cells, producing few metaphases when thousands are required, e.g. in biological dosimetry studies. We show that staphylococcal enterotoxin A (SEA), one of the most potent mitogens known, at a concentration of 0.5 microgram/ml stimulated peripheral lymphocytes to grow with a mitotic index (MI) averaging 0.13 metaphases/cell in old, irradiated rhesus macaques. This was significantly greater (p < 0.001) than that produced by PHA (MI < 0.01) in lymphocytes from the same animals. Whole blood was cultured for 96, 120 and 144 h for five irradiated individuals and for two controls. All cells cultured with SEA produced a high MI with a peak response at 120 h whereas the same cultures showed low MI for each PHA stimulated culture.


Asunto(s)
Enterotoxinas/farmacología , Linfocitos/efectos de los fármacos , Metafase/efectos de los fármacos , Envejecimiento , Animales , Linfocitos/citología , Linfocitos/efectos de la radiación , Macaca mulatta , Metafase/efectos de la radiación , Índice Mitótico/efectos de los fármacos , Índice Mitótico/efectos de la radiación , Fitohemaglutininas/farmacología
12.
Adv Space Res ; 14(10): 267-70, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11539960

RESUMEN

Protons of a specific energy, 55 MeV, have been found to induce primary high grade astrocytomas (HGA) in the Rhesus monkey (Macaca mulatta). Brain tumors of this type were not induced by protons of other energies (32-2,300 MeV). Induction of HGA has been identified in human patients who have had radiation therapy to the head. We believe that the induction of HGA in the monkey is a consequence of dose distribution, not some unique "toxic" property of protons. Comparison of the human experience with the monkey data indicates the RBE for induction of brain tumors to be about one. It is unlikely that protons cause an unusual change in oncogenic expression, as compared to conventional electromagnetic radiation.


Asunto(s)
Astrocitoma/etiología , Neoplasias Inducidas por Radiación , Protones , Radiación Ionizante , Animales , Relación Dosis-Respuesta en la Radiación , Ependimoma/etiología , Humanos , Macaca mulatta , Dosis de Radiación , Efectividad Biológica Relativa
13.
Adv Space Res ; 14(10): 501-5, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11539986

RESUMEN

Retrospective and ongoing analyses of clinical records from 347 primary intraocular melanoma patients treated with helium ions at LBL will allow examination of the exposure-response data for human cataract; which is a complication of the therapy from incidental exposure of the lens. Direct particle beam traversal of at least a portion of the lens usually is unavoidable in treatment of posterior intraocular tumors. The precise treatment planned for each patient permits quantitative assessment of the lenticular dose and its radiation quality. We are reporting our preliminary results on the development of helium-ion-induced lens opacifications and cataracts in 54 of these patients who had 10% or less of their lens in the treatment field. We believe these studies will be relevant to estimating the human risk for cataract in space flight.


Asunto(s)
Catarata/etiología , Helio/efectos adversos , Cristalino/efectos de la radiación , Melanoma/radioterapia , Neoplasias de la Úvea/radioterapia , Adulto , Medicina Aeroespacial , Anciano , Estudios de Seguimiento , Humanos , Iones , Persona de Mediana Edad , Aceleradores de Partículas , Traumatismos por Radiación/etiología , Radioterapia/efectos adversos , Medición de Riesgo
14.
Radiat Res ; 138(3): 401-8, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8184015

RESUMEN

We report the results of a study on the immunoglobulin levels of rhesus monkeys (Macaca mulatta) in a colony consisting of the survivors of monkeys that received a single whole-body exposure to protons, electrons or X rays between 1964 and 1969. This colony has been maintained to assess the long-term effects of ionizing radiation on astronauts and high-flying pilots. Of the original 358 monkeys that were retained for lifetime studies, 129 (97 irradiated and 32 controls) were available for our study. We found no significant difference between the irradiated and control monkeys in mean levels of IgA, IgG and IgM, irrespective of the radiation treatment. The availability of these aged monkeys provided a unique opportunity to compare their immunoglobulin levels to those of other monkeys of various ages, and thus assess the effect of age on immunoglobulin levels. We found that only the IgA levels increase with age.


Asunto(s)
Inmunoglobulina A/metabolismo , Inmunoglobulina G/metabolismo , Inmunoglobulina M/metabolismo , Factores de Edad , Animales , Femenino , Macaca mulatta , Masculino , Factores Sexuales , Irradiación Corporal Total
15.
Adv Space Res ; 12(2-3): 379-84, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-11537034

RESUMEN

Rhesus monkeys that were exposed in 1969, at the age of approximately 2 years, to low doses of "mixed-energy" protons (10- and 110-MeV) are exhibiting progressive (degenerative) lenticular changes. We have conducted regular examinations of this group of monkeys for cataractogenic development since 1987, i.e., 18 years after irradiation, and the animals began to show enhanced degrees of lenticular opacification two years later. The lenses of age-matched controls (median lifespan in captivity approximately 24 years) continue to exhibit much lower levels of opacification (senile cataracts). Trends in the new data are consistent with the cataractogenic patterns observed for other groups of monkeys that were exposed at similar ages in 1964 and 1965 to protons of different energies, and which we began to monitor only 20-21 years later. Therefore, the new information from the mixed-energy group of monkeys provides insight into the development of late cataractogenic sequelae in the other groups of animals during the 2-3 years before we began to measure them. Comparisons are also made here among recent results from the different groups of primates and from New Zealand white (NZW) rabbits that were exposed when young to 56Fe ions and monitored continuously thereafter. This is done because analogous expression of radiation-induced degenerative cataractogenesis also occurs late in the lifespan of the lagomorphs (control median lifespan in captivity approximately 5-7 years), but in this case the cataractogenic profile has been documented through most of the post-irradiation lifespan.


Asunto(s)
Catarata/etiología , Hierro/efectos adversos , Cristalino/patología , Protones/efectos adversos , Traumatismos Experimentales por Radiación/etiología , Animales , Catarata/patología , Radiación Cósmica , Cristalino/efectos de la radiación , Estudios Longitudinales , Macaca mulatta , Fotones/efectos adversos , Conejos , Traumatismos Experimentales por Radiación/patología , Sistema Solar , Vuelo Espacial
16.
Radiat Res ; 126(2): 147-56, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-1850851

RESUMEN

Rhesus monkeys (Macaca mulatta) which were irradiated at ca. 2 years of age with acute doses (less than or equal to 5 Gy) of protons (32-2300 MeV) are exhibiting the late progressive phase of radiation cataractogenesis 20-24 years after exposure, the period during which we have been monitoring the sequelae of irradiation of the lens. The median life span of the primate is approximately 24 years. Analogous late ocular changes also occur in a similar period of the lifetimes of New Zealand White (NZW) rabbits (Oryctolagus cuniculus) exposed at 8-10 weeks of age to 460-MeV 56Fe ions. In this experiment, which has been in progress for ca. 6 years, we are following the development of radiation-induced lenticular opacification (cataractogenic profiles) throughout the life span. The median life span of the lagomorph is 5-7 years. Cataractogenic profiles for NZW rabbits irradiated with 20Ne and 40Ar ions and 60Co gamma photons were obtained previously. Reference is also made to measurements of the cataractogenic profiles of a short-lived rodent, the Fischer 344 rat (Rattus norvegicus) during the first year after exposure at 8-10 weeks of age to spread-Bragg-peak protons of 55 MeV nominal energy. The median life span of the rodent is reported to be 2-3 years.


Asunto(s)
Catarata/etiología , Cristalino/efectos de la radiación , Protones , Vuelo Espacial , Animales , Macaca mulatta , Conejos , Ratas , Ratas Endogámicas F344 , Factores de Tiempo
17.
Proc R Soc Lond B Biol Sci ; 237(1286): 27-42, 1989 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-2569200

RESUMEN

Synchronous suspensions of the radiosensitive S/S variant of the L5178Y murine leukaemic lymphoblast at different positions in the cell cycle were exposed aerobically to segments of heavy-ion beams (20Ne, 28Si, 40Ar, 56Fe and 93Nb) in the Bragg plateau regions of energy deposition. The incident energies of the ion beams were in the range of 460 +/- 95 MeV u-1, and the calculated values of linear energy transfer (LET infinity) for the primary nuclei in the irradiated samples were 33 +/- 3, 60 +/- 3, 95 +/- 5, 213 +/- 21 and 478 +/- 36 keV microns-1, respectively; 280 kVp X-rays were used as the baseline radiation. Generally, the maxima or inflections in relations between relative biological effectiveness (RBE) and LET infinity were dependent upon the cycle position at which the cells were irradiated. Certain of those relations were influenced by post-irradiation hypothermia. Irradiation in the cell cycle at mid-G1 to mid-G1 + 3 h, henceforth called G1 to G1 + 3 h, resulted in survival curves that were close approximations to simple exponential functions. As the LET infinity was increased, the RBE did not exceed 1.0, and by 478 keV microns-1 it had fallen to 0.39. Although similar behaviour has been reported for inactivation of proteins and certain viruses by ionizing radiations, so far the response of the S/S variant is unique for mammalian cells. The slope of the survival curve for X-photons (D0: 0.27 Gy) is reduced in G1 to G1 + 3 h by post-irradiation incubation at hypothermic temperatures and reaches a minimum (Do: 0.51 Gy) at 25 degrees C. As the LET infinity was increased, however, the extent of hypothermic recovery was reduced progressively and essentially was eliminated at 478 keV microns-1. At the cycle position where the peak of radioresistance to X-photons occurs for S/S cells, G1 + 8 h, increases in LET infinity elicited only small increases in RBE (at 10% survival), until a maximum was reached around 200 keV microns-1. At 478 keV microns-1, what little remained of the variation in response through the cell cycle could be attributed to secondary radiations (delta rays) and smaller nuclei produced by fragmentation of the primary ions.


Asunto(s)
Ciclo Celular/efectos de la radiación , Células Tumorales Cultivadas/efectos de la radiación , Animales , Supervivencia Celular/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Leucemia L5178/patología , Ratones , Radioisótopos , Células Tumorales Cultivadas/citología
18.
Adv Space Res ; 9(10): 125-30, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-11537284

RESUMEN

In an experiment examining the effects of space radiations on primates, different groups of rhesus monkeys (Macaca mulatta) were exposed to single whole-body doses of 32- or 55-MeV protons. Survivors of those exposures, together with age-matched controls, have been monitored continuously since 1964 and 1965. Late effects of nominal proton doses ranging from 2-6 Gray have been measured in vitro using skin fibroblasts from the animals. A logical extension of that study is reported here, and it involves observations of wound healing after 3-mm diameter dermal punches were removed from the ears (pinnae) of control and irradiated monkeys. Tendencies in the reduction of competence to repair cutaneous wounds have been revealed by the initial examinations of animals that received doses greater than 2 Gy more than 2 decades earlier. These trends indicate that this method of assessing radiation damage to skin exposed to high-energy radiations warrants further study.


Asunto(s)
Protones/efectos adversos , Traumatismos Experimentales por Radiación/fisiopatología , Piel/patología , Piel/efectos de la radiación , Cicatrización de Heridas/efectos de la radiación , Animales , Biopsia/métodos , Relación Dosis-Respuesta en la Radiación , Femenino , Fibroblastos/patología , Fibroblastos/efectos de la radiación , Macaca mulatta , Masculino , Vuelo Espacial , Cicatrización de Heridas/fisiología
19.
Adv Space Res ; 9(10): 325-31, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-11537312

RESUMEN

Radiation cataractogenesis induced by small acute doses of particulate radiations and photons in the New Zealand white (NZW) rabbit (Oryctolagus cuniculus), the beagle dog (Canis familiaris) and the rhesus monkey (Macaca mulatta) is discussed in the context of the use of animal models to assess the radiation hazards faced by humans during lengthy sojourns in deep space. Attention is paid to: 1) the importance of lifespan studies with long-lived species--the above animals have median lifespans in captivity of 5-7, 13-14 and approximately 25 years, respectively; 2) the magnitudes of possible dose thresholds for cataractogenesis from sparsely ionizing radiations and the modifications of those thresholds by the late degenerative phase of the phenomenon.


Asunto(s)
Catarata/etiología , Modelos Animales de Enfermedad , Fotones/efectos adversos , Traumatismos Experimentales por Radiación/etiología , Animales , Catarata/patología , Radiación Cósmica , Progresión de la Enfermedad , Perros , Relación Dosis-Respuesta en la Radiación , Rayos gamma/efectos adversos , Iones , Hierro/efectos adversos , Cristalino/fisiología , Cristalino/efectos de la radiación , Macaca mulatta , Conejos , Traumatismos Experimentales por Radiación/patología , Vuelo Espacial , Factores de Tiempo
20.
Adv Space Res ; 9(10): 99-104, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-11537320

RESUMEN

Theories of cellular radiation sensitivity that preclude a significant role for cellular repair processes in the final biological expression of cellular damage induced by ionizing radiation are unsound. Experiments are discussed here in which the cell-cycle dependency of the repair deficiency of the S/S variant, of the L5178Y murine leukemic lymphoblast was examined by treatment with the heavy ions, 20Ne, 28Si, 40Ar, 56Fe and 93Nb. Evidence from those studies, which will be described in detail elsewhere, provide support for the notion that as the linear energy transfer (LET infinity) of the incident radiation increases the ability of the S/S cell to repair radiation damage decreases until effectively it is eliminated around 500 keV/micrometer. In the region of the latter LET infinity value, the behavior of the S/S cell approximates the ideal case of target theory where post-irradiation metabolism (repair) does not influence cell survival. The expression of this phenomenon among different cell types and tissues will depend upon the actual repair systems involved and other considerations.


Asunto(s)
Supervivencia Celular/efectos de la radiación , Reparación del ADN , Iones , Leucemia Linfoide/patología , Transferencia Lineal de Energía , Animales , Bromodesoxiuridina , Bromouracilo , Ciclo Celular/efectos de la radiación , Leucemia Linfoide/metabolismo , Ratones , Células Tumorales Cultivadas
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