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1.
Environ Pollut ; 237: 196-204, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29482025

RESUMEN

Perchlorate (ClO4-) contamination has been reported in ground and surface waters across North America. However, few studies have examined the effects of prolonged exposure to this thyroid hormone disrupting chemical, particularly at environmentally relevant concentrations in lower vertebrates, such as amphibians. The aim of this study was to examine the effects of a yearlong chronic exposure to ClO4- in adult male and female Western clawed frogs (Silurana tropicalis). Frogs were spawned and raised from fertilized embryo until sexual maturity in potassium perchlorate (KClO4)-treated water at different concentrations (0, 20, 53, and 107 µg/L). Developmental and reproductive indices - including adult morphology, androgen plasma levels, gonadal thyroid hormone- and sex steroid-related transcript levels, and sperm motility - were evaluated in male and female adult frogs. Female growth (e.g., body mass, snout-vent length, and hind limb length) was significantly reduced following chronic exposure to environmentally relevant concentrations of KClO4 resulting in females with morphometric indices similar to those of control males - indicating potential sex-specific sensitivities to KClO4. Changes to reproductive indices (i.e., plasma androgen levels, gonadal thyroid hormone- and sex steroid-related transcript levels, and sperm motility) were also observed in both sexes and suggest that KClO4 exposure may also have indirect secondary effects on the reproductive axes in male and female adult frogs. These effects were observed at concentrations at or below those reported in surface waters contaminated with ClO4- suggesting that this contaminant may have developmental and reproductive effects post-metamorphosis in natural amphibian populations.


Asunto(s)
Percloratos/toxicidad , Motilidad Espermática/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Xenopus/fisiología , Animales , Anuros , Femenino , Hormonas Esteroides Gonadales , Gónadas/efectos de los fármacos , Estadios del Ciclo de Vida , Masculino , Metamorfosis Biológica/efectos de los fármacos , América del Norte , Reproducción/efectos de los fármacos , Glándula Tiroides , Hormonas Tiroideas
2.
J Holist Nurs ; 36(3): 210-217, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27587296

RESUMEN

As part of a study of a larger study of self-identified holistic nurses, researchers asked nurses to describe practice situations where energy-based modalities (EBMs) were used. Four hundred and twenty-four nurses responded by writing free-text responses on an online survey tool. The participants were highly educated and very experienced with 42% holding graduate degrees and 77% having over 21 years of practice. Conventional content analysis revealed four themes: EMBs are 1) caring modalities used to treat a wide range of identified nursing concerns; 2) implemented across the life span and to facilitate life transitions; 3) support care for the treatment of specific medical conditions; and 4) Use of EBMs transcend labels of 'conditions' and are used within a holistic framework. The fourth theme reveals a shared vision of nursing work such that the modality becomes secondary and the need to address the 'whole' at an energetic level emerges as the primary focus of holistic nursing.


Asunto(s)
Transferencia de Energía , Enfermería Holística/métodos , Humanos , Enfermeras y Enfermeros/psicología , Investigación Cualitativa
3.
Gen Comp Endocrinol ; 259: 34-44, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29107601

RESUMEN

Thyroid hormones (THs) and androgens have been shown to be extensively involved in sexual development; however, relatively little is known with regard to TH-related and androgenic actions in sex determination. We first established expression profiles of three sex-determining genes (sf1, dax-1, and sox9) during the embryonic development of Western clawed frogs (Silurana tropicalis). Transcripts of sf1 and sox9 were detected in embryos before the period in which embryonic transcription commences indicating maternal transfer, whereas dax-1 transcripts were not detected until later in development. To examine whether TH status affects sex-determining gene expression in embryonic S. tropicalis, embryos were exposed to co-treatments of iopanoic acid (IOP), thyroxine (T4), or triiodothyronine (T3) for 96 h. Expression profiles of TH receptors and deiodinases reflect inhibition of peripheral deiodinase activity by IOP and recovery by T3. Relevantly, elevated TH levels significantly increased the expression of sf1 and dax-1 in embryonic S. tropicalis. Further supporting TH-mediated regulation, examination of the presence and frequency of transcription factor binding sites in the putative promoter regions of sex-determining genes in S. tropicalis and rodent and fish models using in silico analysis also identified TH motifs in the putative promoter regions of sf1 and dax-1. Together these findings advocate that TH actions as early as the period of embryogenesis may affect gonadal fate in frogs. Mechanisms of TH and androgenic crosstalk in relation to the regulation of steroid-related gene expression were also investigated.


Asunto(s)
Andrógenos/metabolismo , Proteínas de Unión al ADN/genética , Regulación del Desarrollo de la Expresión Génica , Hormonas Tiroideas/metabolismo , Factores de Transcripción/genética , Proteínas de Xenopus/genética , Xenopus/embriología , Xenopus/genética , Animales , Proteínas de Unión al ADN/metabolismo , Femenino , Expresión Génica/efectos de los fármacos , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Yoduro Peroxidasa/metabolismo , Masculino , Ratones , Regiones Promotoras Genéticas/genética , Procesos de Determinación del Sexo/genética , Factores de Transcripción/metabolismo , Triyodotironina/metabolismo , Proteínas de Xenopus/metabolismo
4.
AIDS Res Hum Retroviruses ; 33(7): 668-674, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28121161

RESUMEN

We assessed CD8+ T cell reactivity to human herpesvirus 8 (HHV-8; Kaposi's sarcoma [KS]-associated herpesvirus) and the role of CD4+CD25hiFoxP3+ regulatory T cells (Treg) in HHV-8- and HIV-coinfected participants of the Multicenter AIDS Cohort Study who did or did not develop KS. There were similarly low CD8+ T cell interferon-γ responses to MHC class I-restricted epitopes of HHV-8 lytic and latent proteins over 5.7 years before KS in participants who developed KS compared to those who did not. T cell reactivity to HHV-8 antigens was low relative to responses to a combination of cytomegalovirus, Epstein-Barr virus and influenza A virus (CEF) peptide epitopes, and dominant HIV peptide epitopes. There was no change in %Treg in the HHV-8- and HIV-coinfected participants who did not develop KS, whereas there was a significant increase in %Treg in HHV-8- and HIV-coinfected participants who developed KS beginning 1.8 years before development of KS. Removal of Treg enhanced HHV-8-specific T cell responses in HHV-8- and HIV-coinfected participants who did or did not develop KS, with a similar pattern observed in response to CEF and HIV peptides. Thus, long-term, low levels of anti-HHV-8 CD8+ T cell reactivity were present in both HHV-8- and HIV-coinfected men who did and did not develop KS. This was related to moderately enhanced Treg function.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Infecciones por Herpesviridae/complicaciones , Infecciones por Herpesviridae/virología , Herpesvirus Humano 8/inmunología , Sarcoma de Kaposi/patología , Sarcoma de Kaposi/virología , Linfocitos T Reguladores/inmunología , Adulto , Antígenos Virales/inmunología , Humanos , Interferón gamma/metabolismo , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Adulto Joven
5.
Health Promot Pract ; 17(1): 40-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26384927

RESUMEN

This article reports on a social marketing campaign directed toward high-risk men who have sex with men in Toronto and Ottawa to encourage testing for HIV and syphilis; improve knowledge about HIV transmission, seroconversion symptoms, and the HIV window period; and heighten awareness of syphilis transmission and its relationship to facilitating HIV transmission. Evaluation data were collected from a large-scale online pre-and postcampaign survey of sexually active men who have sex with men and from laboratory testing data. Men who turned up to be tested also filled out an exit survey. The campaign websites attracted some 15,000 unique visitors, 54% of whom had an IP address in Toronto or Ottawa. Laboratory data showed a 20% increase in HIV testing in Toronto over the campaign compared to the previous year. The overall rate of HIV-positive tests remained relatively constant. Knowledge levels about seroconversion symptoms, sexually transmitted infection and HIV transmission, and the HIV window period were significantly better among postcampaign survey respondents aware of the campaign compared to postcampaign respondents who were not aware and compared to precampaign respondents.


Asunto(s)
Infecciones por VIH/diagnóstico , Infecciones por VIH/psicología , Conocimientos, Actitudes y Práctica en Salud , Promoción de la Salud/métodos , Homosexualidad Masculina/psicología , Adolescente , Adulto , Bisexualidad , Encuestas Epidemiológicas , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Internet , Modelos Logísticos , Masculino , Persona de Mediana Edad , Ontario , Evaluación de Programas y Proyectos de Salud , Mercadeo Social , Sífilis/diagnóstico , Adulto Joven
6.
Front Microbiol ; 5: 452, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25221546

RESUMEN

Human herpesvirus 8 (HHV-8; Kaposi's sarcoma-associated herpesvirus) is an oncogenic gammaherpesvirus that primarily infects cells of the immune and vascular systems. HHV-8 interacts with and targets professional antigen presenting cells and influences their function. Infection alters the maturation, antigen presentation, and immune activation capabilities of certain dendritic cells (DC) despite non-robust lytic replication in these cells. DC sustains a low level of antiviral functionality during HHV-8 infection in vitro. This may explain the ability of healthy individuals to effectively control this virus without disease. Following an immune compromising event, such as organ transplantation or human immunodeficiency virus type 1 infection, a reduced cellular antiviral response against HHV-8 compounded with skewed DC cytokine production and antigen presentation likely contributes to the development of HHV-8 associated diseases, i.e., Kaposi's sarcoma and certain B cell lymphomas. In this review we focus on the role of DC in the establishment of HHV-8 primary and latent infection, the functional state of DC during HHV-8 infection, and the current understanding of the factors influencing virus-DC interactions in the context of HHV-8-associated disease.

8.
PLoS One ; 8(6): e66298, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23762485

RESUMEN

The recent West Nile virus (WNV) outbreak in the United States underscores the importance of understanding human immune responses to this pathogen. Via the presentation of viral peptide ligands at the cell surface, class I HLA mediate the T cell recognition and killing of WNV infected cells. At this time, there are two key unknowns in regards to understanding protective T cell immunity: 1) the number of viral ligands presented by the HLA of infected cells, and 2) the distribution of T cell responses to these available HLA/viral complexes. Here, comparative mass spectroscopy was applied to determine the number of WNV peptides presented by the HLA-A*11:01 of infected cells after which T cell responses to these HLA/WNV complexes were assessed. Six viral peptides derived from capsid, NS3, NS4b, and NS5 were presented. When T cells from infected individuals were tested for reactivity to these six viral ligands, polyfunctional T cells were focused on the GTL9 WNV capsid peptide, ligands from NS3, NS4b, and NS5 were less immunogenic, and two ligands were largely inert, demonstrating that class I HLA reduce the WNV polyprotein to a handful of immune targets and that polyfunctional T cells recognize infections by zeroing in on particular HLA/WNV epitopes. Such dominant HLA/peptide epitopes are poised to drive the development of WNV vaccines that elicit protective T cells as well as providing key antigens for immunoassays that establish correlates of viral immunity.


Asunto(s)
Epítopos de Linfocito T/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Fragmentos de Péptidos/inmunología , Fiebre del Nilo Occidental/inmunología , Virus del Nilo Occidental/inmunología , Adulto , Anciano , Western Blotting , Células Cultivadas , Cromatografía Líquida de Alta Presión , Femenino , Citometría de Flujo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena en Tiempo Real de la Polimerasa , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Fiebre del Nilo Occidental/prevención & control , Fiebre del Nilo Occidental/virología , Adulto Joven
9.
Clin Cancer Res ; 18(8): 2382-90, 2012 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-22351697

RESUMEN

PURPOSE: Secondary lymphedema is a frequent complication of breast cancer associated with surgery, chemotherapy, or radiation following breast cancer treatment. The potential contribution of genetic susceptibility to risk of developing secondary lymphedema following surgical trauma, radiation, and other tissue insults has not been studied. EXPERIMENTAL DESIGN: To determine whether women with breast cancer and secondary lymphedema had mutations in candidate lymphedema genes, we undertook a case-control study of 188 women diagnosed with breast cancer recruited from the University of Pittsburgh Breast Cancer Program (http://www.upmccancercenter.com/breast/index.cfm) between 2000 and 2010. Candidate lymphedema genes, GJC2 (encoding connexin 47 [Cx47]), FOXC2, HGF, MET, and FLT4 (encoding VEGFR3), were sequenced for mutation. Bioinformatics analysis and in vitro functional assays were used to confirm significance of novel mutations. RESULTS: Cx47 mutations were identified in individuals having secondary lymphedema following breast cancer treatment but not in breast cancer controls or normal women without breast cancer. These novel mutations are dysfunctional as assessed through in vitro assays and bioinformatics analysis and provide evidence that altered gap junction function leads to lymphedema. CONCLUSIONS: Our findings challenge the view that secondary lymphedema is solely due to mechanical trauma and support the hypothesis that genetic susceptibility is an important risk factor for secondary lymphedema. A priori recognition of genetic risk (i) raises the potential for early detection and intervention for a high-risk group and (ii) allows the possibility of altering surgical approach and/or chemo- and radiation therapy, or direct medical treatment of secondary lymphedema with novel connexin-modifying drugs.


Asunto(s)
Neoplasias de la Mama/genética , Conexinas/genética , Linfedema/genética , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Estudios de Casos y Controles , Línea Celular Tumoral , Femenino , Predisposición Genética a la Enfermedad , Células HeLa , Humanos , Linfedema/tratamiento farmacológico , Persona de Mediana Edad , Factores de Riesgo , Análisis de Secuencia de ADN , Adulto Joven
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